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.

The inhibition of oleic acid induced hepatic lipogenesis and the promotion of lipolysis by caffeic acid via up-regulation of AMP-activated kinase.

BACKGROUND: Caffeic acid (CA) can inhibit toxin-induced liver injury. In this study, CA is assessed for its lipid lowering potential when oleic acid is used to induce non-alcoholic fatty liver disease in human HepG2 cells. RESULTS: The results showed that both the triglyceride and cholesterol content are decreased in the HepG2 cells by using the enzymatic colorimetric method. CA enhances the phosphorylation of AMP-activated protein kinase (AMPK) and its primary downstream targeting enzyme, acetyl-CoA carboxylase. CA down-regulates the lipogenesis gene expression of sterol regulatory element-binding protein-1 and its target genes, fatty acid synthase in the presence of oleic acid. In addition, CA significantly decreases cholesterol and triglyceride production via inhibition the expression of both 3-hydroxy-3-methyglutary coenzyme A reductase and glycerol-3-phosphate acyltransferase. These effects are eliminated by pretreatment with compound C, an AMPK inhibitor. CONCLUSIONS: These results demonstrate that CA inhibits oleic acid induced hepatic lipogenesis and the promotion of lipolysis via up-regulation of AMP-activated kinase.