Metformin For Treatment Of Nonalcoholic Fatty Liver Disease And The Ralated Mechanism Of Autophagy

Objective:To investigate metformin for treatment of nonalcoholic fatty liver disease and the possible mechanism of action.Method:Oleic acid(OA)induced HepG2 cells to establish nonalcoholic fatty liver disease cell model.HepG2 cells treated with or without oleic acid were divided five groups,including the blank control group,model group,control+metformin group,oleic acid+metformin group,oleic+metformin+3-methyladenine group.Oil red O staining and Bodipy493/503 fluorescent staining was done to observe each group cell fatty degeneration.DCFH-DA fluorescent probe were used to detect the changes of intracellular reactive oxygen species(ROS).The apoptosis of the HepG2 was detected by Annexin V-FITC/PI and Hoechst 33258 staining.The MDC fluorescence staining and Western blot method to detect cell autophagy level.Results:The experiments were found by Bodipy493/503 fluorescence staining that Metformin can improve hepatic steatosis in HepG2.However,when Metformin combinated with 3-Ma,the protective effect against hepatic steatosis was partly inhibited.Metformin can obviously improve the oleic acid-induced HepG2 cell oxidative stress levels,which is characterized by intracellular ROS levels,compared with model group,intracellular ROS levels significantly decreased in Metformin intervention group,and the effect can be weakened in Metformin combination with 3-Ma compared with Metformin intervention group.The results from Flow cytometry and Hoechst 33258 staining indicate that Metformin can suppress the oleic acid-induced HepG2 cell apoptosis,and the inhibition effect is blocked when combined with 3-Ma.The result of MDC fluorescence staining and Western blot for Beclin-1 and LC3-IIshows that Metformin can promotes autophagy in Steatosis HepG2,and 3-Ma can partly inhabited the promotion.Conclusion:Metformin can ameliorate the oleic acid-induced hepatic steatosis in HepG2 cell through reducing cell apoptosis,inhibiting oxidative stress and enhancing cell autophagy activation.