Abstract
OBJECTIVES: To explore therapeutic mechanism of Hugan Tang (Hugan Decoction, HGT) for alleviating non-alcoholic fatty liver disease (NAFLD) in rats. METHODS: Network pharmacology analysis was used to predict the active components of HGT against NAFLD and their potential targets, and the core targets were identified using the protein-protein interaction network, followed by GO and KEGG pathway enrichment analyses. A rat model of high-fat diet (HFD)-induced NAFLD was used to test the effects of saline, silymarin, and low-, moderate-, and high-dose HGT on serum levels of ALT, AST, LDL, LDH, TG and TC, liver histopathology, and protein and mRNA expressions of ACC1, FASN, AMPK and m-TOR. In free fatty acid (FFA)-induced HepG2 cells, the effects of blank and HGT-medicated sera, compound C (an AMPK inhibitor), and MHY1485 (a mTOR agonist) were tested on cell viability, intracellular lipid deposition, TC and TG levels, and expressions of ACC1, FASN, AMPK and m-TOR. RESULTS: We identified 130 active components in HGT, 267 common targets with NAFLD, and 53 core gene nodes, nearly half of which were involved in lipid metabolism. HGT treatment of NAFLD was closely associated with lipid and atherosclerosis signaling, insulin resistance signaling, and AMPK signaling. In rat models of NAFLD, HGT significantly alleviated liver injury and lipid accumulation, and suppressed mRNA and protein expressions of ACC1 and FASN. In FFA-induced HepG2 cells, HGT-medicated serum obviously reduced TG and TC levels and inhibited ACC1 and FASN mRNA and protein expressions. The results of in vitro and in vivo experiments both demonstrated that HGT activated the AMPK/mTOR signaling pathway by promoting p-AMPK expression and suppressing p-mTOR expression, and its regulatory effects on p-AMPK, p-mTOR, ACC1, and FASN were differentially modulated by compound C and MHY1485. CONCLUSIONS: HGT alleviates NAFLD in rats by activating the AMPK/m-TOR signaling pathway and reducing lipid synthesis.