Baicalin ameliorates alcohol-induced hepatic steatosis by suppressing SREBP1c elicited PNPLA3 competitive binding to ATGL

Baicalin is a flavonoid compound abundant in multiple edible and medicinal plants such as Scutellaria baicalensis Georgi. In this study, we provide evidence to support the fact that baicalin ameliorates alcohol-induced hepatic steatosis via regulating SREBP1c elicited PNPLA3 competitive binding to ATGL. Results showed that baicalin significantly attenuated the development of metabolic disorders and hepatic steatosis in alcohol-induced rats after four weeks of treatment. It was evident that baicalin treatment significantly normalized the serous contents of hepatic triglyceride (TG), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), and attenuated the increase of hepatic vacuolization and Oil Red O staining area caused by alcohol. Meanwhile, baicalin relieves alcohol-induced hepatic fibrosis by masson staining and RT-qPCR analysis. Mechanistically, alcohol aggravated the nuclear expression of SREBP1c, which contributed to the high expression of PNPLA3 and FASN, thereby enhancing the binding of PNPLA3 to ABHD5, and indirectly impairing the binding ability between ATGL and ABHD5, ultimately causing a decline in the hydrolysis capacity in liver lipid droplets. As expected, these alcohol-induced pathobolism were reversed by baicalin treatment both in vivo and in vitro. In conclusion, this study has demonstrated that baicalin can protect against alcohol-induced hepatic lipid accumulation by activating hepatic lipolysis via suppressing SREBP1c elicited PNPLA3 competitive binding to ATGL. Baicalin is a promising natural product for preventing alcohol-induced hepatic steatosis.