A. J. Lewis1, X. Zhang1, M. R. Rosengart1,2 1University Of Pittsburgh,Department Of Surgery,Pittsburgh, PA, USA 2University Of Pittsburgh,Department Of Critical Care Medicine,Pittsburgh, PA, USA
Introduction:
Temsirolimus is a rapamycin analog shown previously by our group to induce autophagy and decrease acute kidney injury (AKI) during endotoxemia in both pre- and post-treatment studies. However, the degree to which it functions as a therapeutic to improve the outcome during established sepsis remains to be determined. Cecal ligation and puncture (CLP) generates a systemic inflammatory response from three insults: surgical tissue trauma, ischemia from the ligated cecum, and host barrier breakdown from cecal puncture; it is considered a physiologically relevant model of surgical sepsis. We hypothesize that after CLP, treatment with temsirolimus will attenuate the host inflammatory response to septic insult and decrease organ injury.
Methods:
Male C57BL/6 mice (8-12 weeks) underwent 1cm ligation, double 21-gauge puncture CLP using ketamine/xylazine anesthesia. No antibiotics were administered. One hour after CLP, mice were randomized to receive a 5 mg/kg intraperitoneal injection of temsirolimus or equivalent volume of diluent. Mice were monitored for 24 hours, euthanized, and plasma and tissue were harvested. Plasma cytokine and Cystatin C concentrations were assayed via ELISA. Alanine aminotransferase (ALT) concentration was determined using a Heska Dri-Chem automated analyzer. Statistical significance (p<0.05) was determined by rank sum.
Results:
When compared to controls, mice receiving temsirolimus exhibited significantly lower concentrations of IL-6 (1253 vs. 32695 pg/mL, p=0.033), TNF-a (36.4 vs. 176.4 pg/mL, p=0.049), and IL-10 (1033 vs. 4146 pg/mL, p=0.017). Cystatin C, a sensitive marker of AKI, was lower in temsirolimus-treated animals (868 vs. 1392 ng/mL, p=0.158). We found no difference in liver injury, as quantified by ALT, between groups (119 vs. 98 U/L, p=0.322).
Conclusion:
Temsirolimus treatment after CLP sepsis reduces systemic inflammation. This reduced inflammation correlated with attenuated AKI, though this did not attain statistical significance. These data suggest that potential exists for the use of temsirolimus as a therapy to reduce deleterious effects of a hyperinflammatory state of sepsis. Further experiments are needed to determine the effects of temsirolimus on host physiology and survival.