Role of STING signaling pathway in CORM-3-induced reduction of hepatocyte pyroptosis and apoptosis in a rat model of hepatic ischemia-reperfusion / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the role of stimulator of interferon genes (STING) signaling pathway in carbon monoxide (CO)-releasing molecule-3 (CORM-3)-induced reduction of hepatocyte pyroptosis and apoptosis in a rat model of hepatic ischemia-reperfusion.Methods:Forty-eight clean-grade healthy male Sprague-Dawley rats, aged 9-11 weeks, weighing 320-380 g, were divided into 4 groups ( n=12 each) using a random number table method: sham operation group (S group), ischemia-reperfusion group (IR group), CORM-3 group (C group) and STING agonist ADU-S100 group (A group).Hepatic ischemia-reperfusion injury models were developed by reversible ligation of left middle hepatic artery, portal vein and bile duct branches for 45 min, followed by reperfusion in anesthetized animals in IR, C and A groups.In group C, CORM-3 4 mg/kg was injected into the femoral vein immediately after reperfusion.The equal volume of normal saline containing dimethyl sulfoxide was injected into the femoral vein in S, IR and A groups.At 1.5 h after injection into the femoral vein, ADU-S100 10 mg/kg was intraperitoneally injected in A group, and the equal volume of normal saline was given instead in S, IR and C groups.The serum alanine transaminase (ALT) and aspartate transaminase (AST) concentrations were determined at 3 h of reperfusion.The rats were sacrificed at 12 h of reperfusion, and liver tissues were collected for determination of the content of CO (by colorimetry), expression of interleukin-1beta (IL-1β), IL-18, Bcl-2, Bax, interferon regulatory factor 3 (IRF3), phosphorylated IRF3 (p-IRF3), STING, NOD-like receptor protein 3 (NLRP3), aspirin D (GSDMD) and activated caspase-1 (by Western blot), and pyroptosis and apoptosis rates of hepatocytes (by immunofluorescence staining).The liver injury was scored. Results:Compared with group S, the serum ALT and AST concentrations, liver injury score, CO content, and pyroptosis and apoptosis rates of hepatocytes were significantly increased, and the expression of IL-1β, IL-18, p-IRF3, STING, NLRP3, GSDMD and activated caspase-1 was up-regulated, and the Bcl-2/Bax ratio was decreased in group IR ( P<0.05).Compared with group IR, the serum ALT and AST concentrations, liver injury score, and pyroptosis and apoptosis rates of hepatocytes were significantly decreased, the CO content was increased, the expression of IL-1β, IL-18, p-IRF3, STING, NLRP3, GSDMD and activated caspase-1 was down-regulated, and the Bcl-2/Bax ratio was increased in group C ( P<0.05).Compared with group C, the serum ALT and AST concentrations, liver injury score, and pyroptosis and apoptosis rates of hepatocytes were significantly increased, the CO content was decreased, the expression of IL-1β, IL-18, p-IRF3, STING, NLRP3, GSDMD and activated caspase-1 was up-regulated, and the Bcl-2/Bax ratio was decreased in group A ( P<0.05). Conclusions:The mechanism by which CORM-3 attenuates hepatocyte pyroptosis and apoptosis may be related to the inhibition of activation of STING signaling pathway in a rat model of hepatic ischemia-reperfusion.