This study investigated the mechanism of action of Scutellariae Radix-Coptidis Rhizoma(SR-CR) in intervening in non-alcoholic fatty liver disease(NAFLD) in rats based on lipidomics. Thirty-six SD rats were divided into a control group, a model group, SR-CR groups of different doses, and a simvastatin group, with six rats in each group. Rats in the control group were fed on a normal diet, while those in the remaining groups were fed on a high-lipid diet. After four weeks of feeding, drug treatment was carried out and rats were sacrificed after 12 weeks. Serum liver function and lipid indexes were detected using kits, and the pathomorphology of liver tissues was evaluated by hematoxylin-eosin(HE) staining and oil red O staining. Changes in lipid levels in rats were detected using the LC-MS technique. Differential lipid metabolites were screened by multivariate statistical analysis, and lipid metabolic pathways were plotted. The changes in lipid-related protein levels were further verified by Western blot. The results showed that compared with the control group, the model group showed increased levels of alanine aminotransferase(ALT), aspartate aminotransferase(AST), total cholesterol(TC), triglyceride(TG), and low-density lipoprotein cholesterol(LDL-c)(P<0.01), and decreased levels of γ-glutamyl transferase(γ-GT) and high-density lipoprotein cholesterol(HDL-c)(P<0.01), which were significantly recovered by the intervention of SR-CR. HE staining and oil red O staining showed that different doses of SR-CR could reverse the steatosis in the rat liver in a dose-dependent manner. After lipidomics analysis, there were significant differences in lipid metabolism between the model group and the control group, with 54 lipids significantly altered, mainly including glycerolipids, phosphatidylcholine, and sphingolipids. After administration, 44 differential lipids tended to normal levels, which indicated that SR-CR groups of different doses significantly improved the lipid metabolism level in NAFLD rats. Western blot showed that SR-CR significantly decreased TG-synthesis enzyme 1(DGAT1), recombinant lipin 1(LPIN1), fatty acid synthase(FASN), acetyl-CoA carboxylase 1(ACC1), and increased the phosphorylation level of ACC1. These changes significantly decreased the synthesis of TG and increased the rate of its decomposition, which enhanced the level of lipid metabolism in the body and finally achieved the lipid-lowering effect. SR-CR can improve NAFLD by inhibiting the synthesis of fatty acids and TG.
Keywords: Scutellariae Radix-Coptidis Rhizoma; lipid metabolism; lipidomics; nonalcoholic fatty liver disease(NAFLD).