SIRT1 improves nonalcoholic fatty liver disease by enhancing chaperone mediated autophagy (CMA) and reducing intracellular lipid accumulation

Abstract

Abstract: Objective To investigate the role of molecular chaperone induced autophagy in the improvement of SIRT1 in the pathological development of nonalcoholic fatty liver disease.Methods Validation SIRT1 under the model of nonalcoholic fatty liver disease and the change of the level of autophagy. In normal liver cells of mice by SIRT1 over expression and useing of palmitic acid and oleic acid for 24 h, detecting the changes of the intracellular triglyceride (TG) and the level of autophagy. Downregulate SIRT1 by siRNA, detecting the change of intracellular triglyceride (TG) and the level of autophagy.Results Compared with the control group, the over-expression group of SIRT1 significantly reduced intracellular triglyceride, and the level of autophagy induced by molecular chaperone in liver cells was up-regulated. Comparing with the control group, the SIRT1 silencing group showed significantly increased intracellular triglycerides and down-regulated autophagy induced by molecular chaperone in liver cells.Conclusion SIRT1 may improve fatty liver disease, by upregulating molecular chaperone-induced autophagy to reduce fat accumulation in hepatocytes.

Key words: Autophagy, SIRT1, non-alcoholic fatty liver disease

MA Ying, MA Ling, MA Ming. SIRT1 improves nonalcoholic fatty liver disease by enhancing chaperone mediated autophagy (CMA) and reducing intracellular lipid accumulation[J]. Chinese Hepatolgy, 2020, 25(12): 1320-1322.

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