1

AGEINGMUDr Jan Plaacuteteniacutek PhD

Uacutestav leacutekařskeacute biochemie a laboratorniacute diagnostiky 1LF UK

What is ageing

bull Progressive loss of physiological capacity in the cells increase in susceptibility to various diseases

bull Not a disease as such

bull Distinguishndash Average life expectancy

bull 2000 men 717 years women 784 years

bull 1920 men 47 years women 496 years

ndash Maximum lifespan

bull For humans 115-120 years does not change

2

What is ageing

bull Looks similar in various animals butproceeds with variable speed hellip must beuniversal process

bull Stochastic process unlike eg embryogenesis is not directly programmedby genome (but genes do play a role )

bull On molecular level inability to keep fidelity of biomolecules

indefinitelybdquosystemic molecular disorderldquo (Hayflick)

What is ageingbull Biological side-reactions hellip spontaneous

permanent non-enzymatic exergonicprocesseshellipeg oxidations glycations

bull rarr Damage to biomolecules such asndash DNA mutations disruption of methylation

patternndash Proteins oxidation glycation cross-

linkingaggregation

bull Not all the damage can be repairedbull At some point the process is accelerated by

bodyrsquos own stress response

Briefly ENTROPY uarruarruarr

3

Free-radical theory of ageing

Accumulation of oxidativedamage with age causes ageingDr Denham Harman 1956

25112014

httpwwwnewswisecomarticlesdr-denham-harman-legendary-scientist-dies-at-age-98

Ionising radiationHydroxyl radical originates from ionisation of water

H2O + hν rarr H + OHmiddot

Reactive oxygen species in the body

One-electron reduction of oxygen (mitochondria NADPH oxidase) forms superoxide O2

middotndash

Dismutation of superoxide produces hydrogen peroxideO2

middotndash + O2middotndash + 2 H+ rarr O2 + H2O2

Fenton reaction with Fe or Cu converts peroxide tohydroxyl radicalH2O2 + Fe2+ rarr OHndash + OHmiddot + Fe3+

4

Mitochondrialgenome

Mitochondrial DNA

mutates 10 times faster

than nuclear DNA

Exposed to oxygen radicals Not covered by histonesRepair insufficient

Vicious circle of mitochondrial oxidativedamage

Production of oxygen radicals in mitochondria

Accumulation of mtDNA mutations with age

Respiratory chain deficiency

Heart failure muscle weakness diabetes mellitus dementia neurodegeneration hellip

5

Free-radicalmitochondrial theory of ageing

bull Accumulation of oxidative damage with age (DenhamHarman 1956)

bull Later refined to mitochondrial theory

ndash hellipmitochondria are the main source of ROS in the body

bull But Difficult to prove that human mitoDNA is more damagedby ROS or that significantly accumulates mutations with age

bull Model of Kirkwood and Kovald

ndash Certain amount of ROS always escapes mitochondria anddamages other cellular structures

ndash Prevention of ROS formation and repair systems are never100 effective

ndash Slightly damaged mitochondria produce less energy thanthe cell would need

Some evidence for free-radicalmitochondrial theory of ageing

Life-time Energy Potential

bull Drosophila lifespan depends on temperature(higher t hellip higher O2 consumption hellip shorter lifespan)

bull Most animals have a fixed quota of heartbeatsamount of O2 consumed

ndash Horse 02 L O2 per kg and hour lives max 35 years

rarr 60 000 L O2 per kg over lifetime

ndash Squirrel 1 L O2 per kg and hour lives max 7 years

rarr 60 000 L O2 per kg over lifetime

(also known as the rate-of-living theory ndash nowadays disproved as a theory of ageing because of many exceptions)

6

Protein GlycationCarbonyl Stress

Maillard reaction (According to Janebovaacute et al Remedia 1999)

Reactive carbonyls (aldehydes)

from lipid peroxidation

Methylglyoxal

Toxic byproduct of glycolysis

Source of AGEs (advanced

glycation end products)

Methylglyoxal

Protein

ArgArg

+

ProteinAGE

AGE(Glyoxalase 1 2 GSH)

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

2

What is ageing

bull Looks similar in various animals butproceeds with variable speed hellip must beuniversal process

bull Stochastic process unlike eg embryogenesis is not directly programmedby genome (but genes do play a role )

bull On molecular level inability to keep fidelity of biomolecules

indefinitelybdquosystemic molecular disorderldquo (Hayflick)

What is ageingbull Biological side-reactions hellip spontaneous

permanent non-enzymatic exergonicprocesseshellipeg oxidations glycations

bull rarr Damage to biomolecules such asndash DNA mutations disruption of methylation

patternndash Proteins oxidation glycation cross-

linkingaggregation

bull Not all the damage can be repairedbull At some point the process is accelerated by

bodyrsquos own stress response

Briefly ENTROPY uarruarruarr

3

Free-radical theory of ageing

Accumulation of oxidativedamage with age causes ageingDr Denham Harman 1956

25112014

httpwwwnewswisecomarticlesdr-denham-harman-legendary-scientist-dies-at-age-98

Ionising radiationHydroxyl radical originates from ionisation of water

H2O + hν rarr H + OHmiddot

Reactive oxygen species in the body

One-electron reduction of oxygen (mitochondria NADPH oxidase) forms superoxide O2

middotndash

Dismutation of superoxide produces hydrogen peroxideO2

middotndash + O2middotndash + 2 H+ rarr O2 + H2O2

Fenton reaction with Fe or Cu converts peroxide tohydroxyl radicalH2O2 + Fe2+ rarr OHndash + OHmiddot + Fe3+

4

Mitochondrialgenome

Mitochondrial DNA

mutates 10 times faster

than nuclear DNA

Exposed to oxygen radicals Not covered by histonesRepair insufficient

Vicious circle of mitochondrial oxidativedamage

Production of oxygen radicals in mitochondria

Accumulation of mtDNA mutations with age

Respiratory chain deficiency

Heart failure muscle weakness diabetes mellitus dementia neurodegeneration hellip

5

Free-radicalmitochondrial theory of ageing

bull Accumulation of oxidative damage with age (DenhamHarman 1956)

bull Later refined to mitochondrial theory

ndash hellipmitochondria are the main source of ROS in the body

bull But Difficult to prove that human mitoDNA is more damagedby ROS or that significantly accumulates mutations with age

bull Model of Kirkwood and Kovald

ndash Certain amount of ROS always escapes mitochondria anddamages other cellular structures

ndash Prevention of ROS formation and repair systems are never100 effective

ndash Slightly damaged mitochondria produce less energy thanthe cell would need

Some evidence for free-radicalmitochondrial theory of ageing

Life-time Energy Potential

bull Drosophila lifespan depends on temperature(higher t hellip higher O2 consumption hellip shorter lifespan)

bull Most animals have a fixed quota of heartbeatsamount of O2 consumed

ndash Horse 02 L O2 per kg and hour lives max 35 years

rarr 60 000 L O2 per kg over lifetime

ndash Squirrel 1 L O2 per kg and hour lives max 7 years

rarr 60 000 L O2 per kg over lifetime

(also known as the rate-of-living theory ndash nowadays disproved as a theory of ageing because of many exceptions)

6

Protein GlycationCarbonyl Stress

Maillard reaction (According to Janebovaacute et al Remedia 1999)

Reactive carbonyls (aldehydes)

from lipid peroxidation

Methylglyoxal

Toxic byproduct of glycolysis

Source of AGEs (advanced

glycation end products)

Methylglyoxal

Protein

ArgArg

+

ProteinAGE

AGE(Glyoxalase 1 2 GSH)

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

3

Free-radical theory of ageing

Accumulation of oxidativedamage with age causes ageingDr Denham Harman 1956

25112014

httpwwwnewswisecomarticlesdr-denham-harman-legendary-scientist-dies-at-age-98

Ionising radiationHydroxyl radical originates from ionisation of water

H2O + hν rarr H + OHmiddot

Reactive oxygen species in the body

One-electron reduction of oxygen (mitochondria NADPH oxidase) forms superoxide O2

middotndash

Dismutation of superoxide produces hydrogen peroxideO2

middotndash + O2middotndash + 2 H+ rarr O2 + H2O2

Fenton reaction with Fe or Cu converts peroxide tohydroxyl radicalH2O2 + Fe2+ rarr OHndash + OHmiddot + Fe3+

4

Mitochondrialgenome

Mitochondrial DNA

mutates 10 times faster

than nuclear DNA

Exposed to oxygen radicals Not covered by histonesRepair insufficient

Vicious circle of mitochondrial oxidativedamage

Production of oxygen radicals in mitochondria

Accumulation of mtDNA mutations with age

Respiratory chain deficiency

Heart failure muscle weakness diabetes mellitus dementia neurodegeneration hellip

5

Free-radicalmitochondrial theory of ageing

bull Accumulation of oxidative damage with age (DenhamHarman 1956)

bull Later refined to mitochondrial theory

ndash hellipmitochondria are the main source of ROS in the body

bull But Difficult to prove that human mitoDNA is more damagedby ROS or that significantly accumulates mutations with age

bull Model of Kirkwood and Kovald

ndash Certain amount of ROS always escapes mitochondria anddamages other cellular structures

ndash Prevention of ROS formation and repair systems are never100 effective

ndash Slightly damaged mitochondria produce less energy thanthe cell would need

Some evidence for free-radicalmitochondrial theory of ageing

Life-time Energy Potential

bull Drosophila lifespan depends on temperature(higher t hellip higher O2 consumption hellip shorter lifespan)

bull Most animals have a fixed quota of heartbeatsamount of O2 consumed

ndash Horse 02 L O2 per kg and hour lives max 35 years

rarr 60 000 L O2 per kg over lifetime

ndash Squirrel 1 L O2 per kg and hour lives max 7 years

rarr 60 000 L O2 per kg over lifetime

(also known as the rate-of-living theory ndash nowadays disproved as a theory of ageing because of many exceptions)

6

Protein GlycationCarbonyl Stress

Maillard reaction (According to Janebovaacute et al Remedia 1999)

Reactive carbonyls (aldehydes)

from lipid peroxidation

Methylglyoxal

Toxic byproduct of glycolysis

Source of AGEs (advanced

glycation end products)

Methylglyoxal

Protein

ArgArg

+

ProteinAGE

AGE(Glyoxalase 1 2 GSH)

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

4

Mitochondrialgenome

Mitochondrial DNA

mutates 10 times faster

than nuclear DNA

Exposed to oxygen radicals Not covered by histonesRepair insufficient

Vicious circle of mitochondrial oxidativedamage

Production of oxygen radicals in mitochondria

Accumulation of mtDNA mutations with age

Respiratory chain deficiency

Heart failure muscle weakness diabetes mellitus dementia neurodegeneration hellip

5

Free-radicalmitochondrial theory of ageing

bull Accumulation of oxidative damage with age (DenhamHarman 1956)

bull Later refined to mitochondrial theory

ndash hellipmitochondria are the main source of ROS in the body

bull But Difficult to prove that human mitoDNA is more damagedby ROS or that significantly accumulates mutations with age

bull Model of Kirkwood and Kovald

ndash Certain amount of ROS always escapes mitochondria anddamages other cellular structures

ndash Prevention of ROS formation and repair systems are never100 effective

ndash Slightly damaged mitochondria produce less energy thanthe cell would need

Some evidence for free-radicalmitochondrial theory of ageing

Life-time Energy Potential

bull Drosophila lifespan depends on temperature(higher t hellip higher O2 consumption hellip shorter lifespan)

bull Most animals have a fixed quota of heartbeatsamount of O2 consumed

ndash Horse 02 L O2 per kg and hour lives max 35 years

rarr 60 000 L O2 per kg over lifetime

ndash Squirrel 1 L O2 per kg and hour lives max 7 years

rarr 60 000 L O2 per kg over lifetime

(also known as the rate-of-living theory ndash nowadays disproved as a theory of ageing because of many exceptions)

6

Protein GlycationCarbonyl Stress

Maillard reaction (According to Janebovaacute et al Remedia 1999)

Reactive carbonyls (aldehydes)

from lipid peroxidation

Methylglyoxal

Toxic byproduct of glycolysis

Source of AGEs (advanced

glycation end products)

Methylglyoxal

Protein

ArgArg

+

ProteinAGE

AGE(Glyoxalase 1 2 GSH)

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

5

Free-radicalmitochondrial theory of ageing

bull Accumulation of oxidative damage with age (DenhamHarman 1956)

bull Later refined to mitochondrial theory

ndash hellipmitochondria are the main source of ROS in the body

bull But Difficult to prove that human mitoDNA is more damagedby ROS or that significantly accumulates mutations with age

bull Model of Kirkwood and Kovald

ndash Certain amount of ROS always escapes mitochondria anddamages other cellular structures

ndash Prevention of ROS formation and repair systems are never100 effective

ndash Slightly damaged mitochondria produce less energy thanthe cell would need

Some evidence for free-radicalmitochondrial theory of ageing

Life-time Energy Potential

bull Drosophila lifespan depends on temperature(higher t hellip higher O2 consumption hellip shorter lifespan)

bull Most animals have a fixed quota of heartbeatsamount of O2 consumed

ndash Horse 02 L O2 per kg and hour lives max 35 years

rarr 60 000 L O2 per kg over lifetime

ndash Squirrel 1 L O2 per kg and hour lives max 7 years

rarr 60 000 L O2 per kg over lifetime

(also known as the rate-of-living theory ndash nowadays disproved as a theory of ageing because of many exceptions)

6

Protein GlycationCarbonyl Stress

Maillard reaction (According to Janebovaacute et al Remedia 1999)

Reactive carbonyls (aldehydes)

from lipid peroxidation

Methylglyoxal

Toxic byproduct of glycolysis

Source of AGEs (advanced

glycation end products)

Methylglyoxal

Protein

ArgArg

+

ProteinAGE

AGE(Glyoxalase 1 2 GSH)

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

6

Protein GlycationCarbonyl Stress

Maillard reaction (According to Janebovaacute et al Remedia 1999)

Reactive carbonyls (aldehydes)

from lipid peroxidation

Methylglyoxal

Toxic byproduct of glycolysis

Source of AGEs (advanced

glycation end products)

Methylglyoxal

Protein

ArgArg

+

ProteinAGE

AGE(Glyoxalase 1 2 GSH)

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

7

Glyoxalase 1 extendslifespan in the worm

C elegans

bull Glyoxalase 1 removes methylglyoxal

bull Its expression in C elegans declines with age

bull Over-expression prolongs lifespan

bull Knock down shortens lifespan

bull Mechanism modification of mitochondrial proteins by methylglyoxal increases production of ROS by the respiratory complex III

Morcos M et al Aging Cell 2008 7 260-269

How the cells get rid of worn-out proteins and organelles

bull Calpains proteasome (short-lived proteins)bull Autophagy (long-lived proteins organelles)

ndash Macroautophagy (whole organelles)ndash Microautophagy (macromolecules small organelles)ndash Chaperone-mediated autophagy (KFERQ proteins)

Fig httpcpmcnetcolumbiaedudeptgsasanatomyFacultyKessinautophagyhtml

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

8

Ageing as a catabolic insufficiencyIncomplete digestion in lysosomes release of Fe from mito

ROS lipid peroxidation cross-linking aggregation andpolymeration of oxidised proteins and lipids

uarr LIPOFUSCIN (in lysosomes)In cytosol defective mito and

indigestible protein aggregates

Loss of hydrolases delivered to lipofuscin-loaded lysosomesDamaged and hypertrophic (giant) mito not degradable

Less ATP more ROS damaged mito amp lysosomes caninitiate apoptosishellip

+

Fig httpwwwuni-mainzdeFBMedizinAnatomieworkshopEMEMtLysohtml

Antioxidant defence V

Stress responseOxidation or nitrosylation of sensor -SH

Transcription factors (NFκB Nrf-2hellip)activation nuclear translocation

Induction of gene expressionbull chaperones (heat shock proteins)bull antioxidant enzymes

bull metallothioneinbull hemoxygenase 1

helliprarr cell more resistant to further

oxidative stress

helliprarr propagation of inflammation

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

9

Stress response becomes permanent in ageing

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Hayflick limitbull Human fibroblast in culture divide no more than 50-

70 times then undergo senescence and diebull Applies to all cultured somatic cells but not to

cancer cellsbull Cells from an elderly donor divide fewer times

copy 1998 GARLAND PUBLISHING

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

10

Telomerase

Telomerase is not thesecret of eternal youth

bull Most cells of human body do not need telomerase(divide infrequently or not at all)

bull Stem cells germinal and activated immune cellspossess telomerase

bull Fibroblasts and epithelial cells never reach the Hayflicklimit in vivo

bull Murine somatic cells express telomerase but stilllifespan of mouse is much shorter than human

bull KO of mouse telomerase gene normal lifespan untillthe 3rd generation then accelerated ageing occurenceof human type cancer (carcinomas)

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

11

What a cell needs to become immortal

bull Cell division (dilution of biologicalsbquogarbagelsquo) or hypoxic slumber

bull Telomerase

bull Mitochondria absent or switched off

hellip Highly specialised postmitotic

neuronal skeletal and cardiac muscle

cells are the most sensitive to ageing

hellip The ultimate limit of our lifespan

Is ageing inevitable in nature

Hydra (Cnidaria)

bull Simple body plan rapid andcomplete renewal from stem cells

bull Nerve net no recognizable brainor muscles

bull Mostly asexual reproduction(budding)

bull No signs of senescence ormortality in captivityEven if achieved in humans by

engineered stem cells replacement of

neuronal cells will change mind and

wipe memorieshellip

Fig httpwwwgeolumdedu~tholtzG331lectures331coralhtml

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

12

Evolution of ageing

Disposable soma theory

(throw-away body)bull Bacteria do not age but for the price of high

selection and mortalitybull Higher organisms

ndash Specialisation

GAMETS haploid (sbquodefect sievelsquo) hugeredundance and high selection but DNA passes to further generation

SOMA diploid longer-lasting butmortal structure DNA not intended forfurther generation

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

13

Disposable soma theoryHow long should the body be maintainedbull In nature most animals never reach senescence

ndash selection shadow for mutations with negative effects late in the lifespan

bull Evolution governed by success in reproduction ndash hellip genes extending post-reproductive period are useless

bull Trade-off between body maintenance and reproduction(metabolic energy is limited)

(TBLKirkwood amp SN Austad Nature 408 (2000) 233-238)

Catastrophic senescence Pacific salmon

httpwwwusgsgovfeatureslewisandclarkChildrenWebSiteshtml

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

14

Animals living longer than predicted by sbquorate-of-livinglsquo theory

(relationship lifespan ndash oxygen consumption)

bull Shell

bull Wings

bull Advanced brain

Fig httpwwwdiscovergalapagoscomtortoisehtmlhttpwwwctrl-cliuseftpimagesanimalsmisc

httpwwwafrican-safari-picturescom

Birds live longer than mammals of equal sizebecause they have better mitochondria

bull RAT lives max 35 years

bull PIDGEON lives 35 years

ndash Metabolic rate comparable to rat

ndash Mitochondrial production of ROS related to O2

consumption about 10 times lower

Fig httpwwwflickrcomphotosfirefalcon143470921

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

15

Evidence for trade-off betweenlongevity and fecundity

bull Lifespan of Drosophila can double over ten generations of selective breeding

ndash Associated with later onset of reproduction number of eggs remains the same

bull Genealogical records of British aristocracy

ndash The longest-lived aristocrats tended to havehad the greatest trouble with fertility

Theory of antagonistic pleiotropy

bull Genes providingadvantage forreproduction butdeleterious later in life

bull Examples in humans

ndash Huntington disease

ndash Hemochromatosis

(TBLKirkwood amp SN Austad Nature

408 (2000) 233-238)

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

16

Good defence against infection in youthChronic inflammationoxidative stress later

Nick Lane Oxygen The Molecule that made the World Oxford University Press 2002

Antioxidants as elixirs of youth

bull Vitamin E (tocopherol)

bull Vitamin C (ascorbate)

bull β-carotene

bull Selenium

Fig httpwwwoselcz

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

17

Free radicals in pathogenesis of human diseases

bull Cause of disease egbull cancerogenesis due to exposition to ionising radiationbull retinopathy of the newborn (fibroplasia retrolentalis)

bull Contribute to pathogenesis egbull atherosclerosisbull diabetes mellitusbull hypertensionbull some kinds of cancerbull brain traumahemorrhagebull ischemiareperfusion injury of heart and other organsbull Parkinson diseasebull Alzheimer diseasebull ageing

bull Merely an epiphenomenon (general consequence of tissue damage)

Antioxidant dietary supplements caneven be harmful

bull Recent meta-analysis of total mortality in 68 studies on administration of antioxidant supplements (232 606 participants 385 publications)

ndash β-carotene vitamin A and vitamin E significantly increase mortality

ndash Vitamin C and selenium have no effect

(Bjelakovic G et al JAMA 2007 297 842-857)

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

18

Why the antioxidants do not help or even harm

bull High doses are ineffectivebull Suppress the beneficial oxidations

ndash Inhibition of the stress responsendash Impair defence against infection cancer

physiologic apoptosis

bull Have other effects in addition to antioxidant ndash tocopherols anti-inflammatoryndash β-carotene co-carcinogen (together with

smoking or environmental toxins)

Caloric restriction extends lifespanbull Restricted amount of food with preserved

quality

bull Works also in higher animals with constant temperature (eg mice rhesus monkeys)ndash Mouse lives for 28 months but dietary restriction

to 25 extends its lifespan to 47 months

bull Really extends the maximum lifespan decreases markers of oxidative stress occurence of cancer and slows down ageing

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

19

Caloric restriction extends lifespanbull Organism bdquowaits outldquoand diverts metabolic energy

from reproduction to maintenance functions

bull Mechanisms ndash Some suppression of IGF-I (somatomedin C) and

insulin signaling

ndash Sirtuins ndash enzymes deacetylating histones p53 etc inhibited by NADH

bull Humans hellip on-going study CALERIE (Comprehensive Assessment of Long-term

Effects of Reducing Intake of Energy)

Adequate physical activity isbeneficial for muscle mitochondriabull Demands for energy stimulate biogenesis and

renewal of muscle mitochondriabull Sublethal or conditioning (eg oxidative) stress

enhances resistance to subsequent more severe stressndash (hellipwhat wonrsquot kill you will make you stronghellip)ndash Mechanism the stress response () hellip induction of heat

shock proteins (chaperones) etcbull Example muscle activity produces ROS but still

benefical

Likewise mental activity may help to renew brain mitochondria

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip

20

httpwwwcalpolyedu~lcimarelknowhtm

Diet rich in fruit and vegetables (optim 5x 80 g daily) is associated with lower risk of

cardiovascular diseases diabetes and certainkinds of cancer (lung oropharynx pancreas

stomach prostate)

(but we do not know whyhellip)

Conclusionbull Immortality and eternal youth are not at hand Ageing

appears to be inevitable consequence of aerobic metabolism of mitochondria in our postmitotic tissues

bull But the rate of ageing can be manipulated

ndash Caloric restriction can increase the maximum lifespan

ndash Physical activity and balanced diet help to reach themaximum lifespan

bull Future ndash Immunomodulation mitochondrial antioxidants drugs

activating sirtuins stem cells modulation of autophagyhellip