Oxidative Stress, Septic Shock, and Survival

Matthew GreenwoodApril 29, 2015

Hypothesis: double blockade of complement C5 and the TLR coreceptor CD14 will improve survival during polymicrobial sepsis

Methods

• Use cecal ligation model to induce polymycrobial sepsis

• Treat C57BL/6 mice with anti-inflammatory agents– Coversin– Anti-mouse CD14

• Monitor – Levels of cytokines and other biomarkers– Mouse survival

What is Coversin?

• Inhibitor of complement C5– Prevents immune chemotaxis– Prevents formation of membrane attack system

• Originally from Ornithodoros moubata

http://www.vipimmunopharma.com/coversin/

http://lymeaware.free.fr/lyme/Websave/maladiesatiques/www.maladies-a-tiques.com/Ornithodoros%20moubata.jpg

Figure 1

Cytokine levels after 24 hours

Figure 2

Inflammatory marker levels after 24 hours.

Figure 3

Inflammatory marker levels after 24 hours.

Figure 4

Subject survival

Conclusions

• Combined C5 and CD14 inhibition significantly improves systemic inflammation, clinical signs, and survival rate

• Reducing the magnitude and duration of both the pro- and anti-inflammatory conditions improves outcome

Future directions

• Correlate cytokine levels with mortality and morbidity

• Treat with antibiotics with the immunosupressants

• Testing in humans to improve patient outcomes

• Hypothesis: protecting mitochondria with mitochondrial targeted antioxidants will alleviate myocardial inflammation and rescue heart function in sepsis

Background

Methods

• Used intratracheal injection of Streptococcus pneumonia to induce sepsis

• Sprague-Dawley male rats served as the model organism

• Administered Mito-Vit-E in a 21.5 uMol/kg dose

Figure 1

Distribution of Mito-Vit-E

Figure 2

Figure 3

Oxidation of molecules

Figure 4

Mitochondrial membrane integrity

Figure 5

Figure 6

Figures 7 & 8

Conclusions

• Mitochondrial targeted Vitamin E– Improved antioxidant capacity– Reduced Oxidation of mitochondrial molecules– Protected mitochondrial structure– Reduced Cytokine production– Reduced neutrophil infiltration– Protected heart function

Future Directions

• Survival studies• Administer with antibiotics• Testing in humans to improve patient

outcomes

My Experiment

Hypothesis: Administration of reactive oxygen species or pro-oxidative species will improve immune response and survival following sepsis

Specific Aim: Determine the reactive oxygen species or oxidants that are able to boost immune response in healthy and immunosuppressed mice to recover from sepsis.

Experimental Approach

• Treat mice with oxidants and mitochondrially targeted antioxidants

• Determine cytokine levels• Find optimal treatment for subject survival