Clinical Research, Investigation, and Systems Modeling of Acute Illness (CRISMA) Laboratory, Department of Critical Care Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States of America.
Medicine Institute, Allegheny Health Network, Pittsburgh, PA, United States of America.
PLoS One. 2020 Nov 5;15(11):e0241122. doi: 10.1371/journal.pone.0241122. eCollection 2020.
Sepsis is the leading cause of death in hospitalized patients and beyond the hospital stay and these long-term sequelae are due in part to unresolved inflammation. Metabolic shift from oxidative phosphorylation to aerobic glycolysis links metabolism to inflammation and such a shift is commonly observed in sepsis under normoxic conditions. By shifting the metabolic state from aerobic glycolysis to oxidative phosphorylation, we hypothesized it would reverse unresolved inflammation and subsequently improve outcome. We propose a shift from aerobic glycolysis to oxidative phosphorylation as a sepsis therapy by targeting the pathways involved in the conversion of pyruvate into acetyl-CoA via pyruvate dehydrogenase (PDH). Chemical manipulation of PDH using dichloroacetic acid (DCA) will promote oxidative phosphorylation over glycolysis and decrease inflammation. We tested our hypothesis in a Drosophila melanogaster model of surviving sepsis infected with Staphylococcus aureus. Drosophila were divided into 3 groups: unmanipulated, sham and sepsis survivors, all treated with linezolid; each group was either treated or not with DCA for one week following sepsis. We followed lifespan, measured gene expression of Toll, defensin, cecropin A, and drosomycin, and levels of lactate, pyruvate, acetyl-CoA as well as TCA metabolites. In our model, metabolic effects of sepsis are modified by DCA with normalized lactate, TCA metabolites, and was associated with improved lifespan of sepsis survivors, yet had no lifespan effects on unmanipulated and sham flies. While Drosomycin and cecropin A expression increased in sepsis survivors, DCA treatment decreased both and selectively increased defensin.
败血症是住院患者死亡的主要原因,且超出了住院时间,这些长期后果部分是由于未解决的炎症。从氧化磷酸化到有氧糖酵解的代谢转变将代谢与炎症联系起来,这种转变在常氧条件下的败血症中很常见。通过将代谢状态从有氧糖酵解转变为氧化磷酸化,我们假设它将逆转未解决的炎症,并随后改善结果。我们提出通过靶向丙酮酸转化为乙酰辅酶 A 的途径,将有氧糖酵解转变为氧化磷酸化为败血症治疗方法,这些途径涉及丙酮酸脱氢酶 (PDH)。使用二氯乙酸 (DCA) 对 PDH 进行化学操作将促进氧化磷酸化而不是糖酵解,并减少炎症。我们在感染金黄色葡萄球菌的存活败血症的黑腹果蝇模型中测试了我们的假设。果蝇分为 3 组:未处理、假处理和败血症幸存者,均用利奈唑胺治疗;每组在败血症后一周内均接受或不接受 DCA 治疗。我们跟踪了寿命,测量了 Toll、防御素、 Cecropin A 和 Drosomycin 的基因表达,以及乳酸盐、丙酮酸、乙酰辅酶 A 以及 TCA 代谢物的水平。在我们的模型中,DCA 改变了败血症的代谢效应,使乳酸盐、TCA 代谢物正常化,并与败血症幸存者的寿命改善相关,而对未处理和假处理的果蝇没有寿命影响。虽然 Drosomycin 和 Cecropin A 在败血症幸存者中的表达增加,但 DCA 治疗降低了两者的表达,并选择性地增加了防御素。