GUT MIROBIOTA

GUT MICROBIOTAThe Human Bacteria

The very quest of Human Being is not targeted to Economic Progress, nor it is to achieve DEIFORM GLORY, but to reflect upon a simple question. Who are we?

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Humans as micro biomes:-- 100 trillion microbes in human intestine. 3 million genes (100X). 2 kg weight. 300-1000 species of bacteria. control almost all body functions.

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COMPOSITION

99 % from 30 40 species.

4 dominant phyla : - Bacteriodetes. - Fermicutes. - Actinobacteria. - Proteobacteria.

Enterotypes : - Prevotella. - Bacteroides. - Ruminococcus.

Variation of Gut Micro biota : - Dependence on Age - Dependence on Geography - Dependence on Diet

Variation with Age

Variation with Diet

Acquisition Of Micro Biota

The 1st week bacteria create a reducing environment.

Strict anaerobic species genera : Bifidobacterium, Bacteroides, Clostridium, and Ruminococcus.

Breast-fed babies : BifidobacteriaFormula-fed infants : Enterobacteriaceae, Enterococci, Bifidobacteria, Bacteroides, and Clostridia.

Immune inactivation in early age.

FUNCTIONS

NUTRITION30% more calories.Short-Chain Fatty Acids (SCFAs)SACCHAROLYTIC FERMENTATIONAcetic acid, Propionic acid and Butyric acid.SCFAs in the caecum. Intestinal SCFAs directly provide energy to colonocytes, absorption into the portal circulation, stimulates adipogenesis.PROTEOLYTIC FERMENTATION Collagen and ElastinToxins, Carcinogens, SCFAs

TROPHIC EFFECTSGrowth of intestinal epithelial cells, lymphoid tissue and control their proliferation and differentiationSodium/Glucose transporters

METABOLISMPositively control the intestinal epithelial cell differentiation , proliferation by production of Short-Chain Fatty Acids.Syntheses of vitamins like Biotin and Folic AcidAbsorption of ions including Magnesium, Calcium and Iron.Metabolize dietary carcinogens - Micro components & Macro componentsMicro - Genotoxic , Heterocyclic Amines (HCAs) Macro - Excessive intake of Fat and Sodium Chloride

IMMUNITYOral ToleranceImmune Exclusion - IgAExpression of TLRs

PROTECTIVE FUNCTIONSCompetitive Exclusion by BARRIER EFFECTBacteriocinsproduces lactic acid and fatty acids, serves to lower the pH in the colonIn alergic patients, C. difficile and S. aureus are higher and lower prevalence of Bacteroides and BifidobacteriaPrevention of IBD

SPECIATIONNasonia giraulti, N. longicornis, N. vitripennisHalogenome

INFLUENCE IN DISEASE

OBESITYfewer Bacteroidetes and more Firmicutesdifferences in the energy-reabsorbing potentialRoux-en-Y gastric bypass (RYGB)Results in significant weight loss improvements in conditions like Type 2 diabetes.29% of their body weight within 3 weeks, despite no change in net food intake.

IBDUlcerative Colitis and Crohn's disease

CANCER Bacteroides and ClostridiumLactobacillus and BifidobacteriaTRANSLOCATIONToo much growth of bacteria in the small intestineReduced immunity of the hostIncreased gut lining permeability in diseases like cirrhosis

MENTAL HEALTHkids with autism were twice as likely as children with other types of disorders to have frequent diarrhoea or colitismice with autism-like symptoms were given a diet with Bacillus fragilisProbiotics have been used to treat ObsessiveCompulsive Disorder (OCD) and Attention- Deficit/Hyperactivity Disorder ADHD.Anxiety often causes nausea and diarrhoea, and depression can change appetite.sociability and risk taking

HEART DISEASETrimethylamine N-oxide (TMAO)AtherosclerosisL-carnitine & Red Meat.

ALTERATIONS

ANTIBIOTICSAntibiotic-Associated Diarrhoea (AAD)Antibiotic-Resistant bacteria.C. difficile and Salmonella kedougouSelective Digestive Tract Decontamination (SDD)Children who were given antibiotics during the first 6 months of life were more likely to have a higher body mass

PHARMABIOTICSProbiotic bacteriaProbiotic-derived biologically active metabolitesPrebioticsSynbiotics or genetically modified commensal bacteriaIBD, Atopy, Infection, Diarrhoea, Cancer & Arthritis

STUDY OF MICROBIOTA

TECHNIQUES OF STUDY

CULTURE DEPENDENT TECHNIQUEScost-effective and reproducible.strict anaerobes, and it is estimated that >80% of the gut micro biota cannot be cultivated under standard laboratory conditions.

CULTURE INDEPENDENT TECHNIQUESMolecular-based techniques.16S ribosomal RNA (rRNA) gene.

MODELS OF STUDYGerm Free AnimalsMono-, Bi-, Poly- Associated AnimalsHuman Flora Associated Animals.

ARE WE REALLY MORE OF BACTERIAL MICROBIOME THAN MAMMALS?

Microbiota as a FORGOTTEN ORGAN ?

What would be the advantage of unicellular organisms becoming multi-cellular?

What differentiates a multi-cellular unit from a colony of unicellular beings living in proximity?

Whether this association will evolve into a more complex system in further evolution of human digestive system?