Activation of the AMPK-mTOR Pathway by Astaxanthin Against Cold Ischemia-Reperfusion in Rat Liver

Abstract

To investigate the protective effect and mechanism of astaxanthin on myocardial injury through activation of AMPK-mTOR pathway. In this study, 32 SPF adult male Wistar rats aged 8 to 10 weeks, weighing 250-300 g were divided into 4 groups (n = 8): sham surgery group (S group), autologous orthotopic liver transplantation group (T group), astaxanthin pretreatment surgery group (Group A) and compound C + astaxanthin pretreatment surgery group (Group C). Group A was given astaxanthin 500 mg/kg, group C received compound C 50 mg/kg + astaxanthin 500 mg/kg once a day for 2 weeks, group S and T received same volume of 0.9% saline. 8 h after portal vein opening, blood samples were collected to determine serum concentrations of TNF-α, IL-6 and HMGB 1 and myocardial injury markers. Myocardial tissue was collected to determine the MDA content, SOD activity and activation of AMPK-mTOR pathway. Compared with the S group, higher serum concentrations of TNF-α, IL-6, HMGB 1, CK-MB, cTnI, and H-FABP in groups T, A, and C, increased MDA content and decreased SOD activity, higher expression of activated Caspase-3 was observed; Compared with the T group, in group A, the serum concentrations of TNF-α, IL-6, and HMGB 1, CB-MB, cTnI, and H-FABP were significantly decreased, with decreased MDA content, increased SOD activity, the reduced expression of activated Caspase-3, elevated P-AMPK/AMPK, and decreased P-mTOR/mTOR. In Conclusion, Astaxanthin protects against liver ischemia-induced myocardial injury in rats mediating by the activation of the AMPK-mTOR pathway.