Abstract

Objective Nonalcoholic fatty liver disease (NAFLD) is a continuum of liver abnormalities from nonalcoholic fatty (NAFL) to nonalcoholic steatohepatitis (NASH), which has become a major public health problem worldwide. Zexie Decoction (ZXD), a traditional Chinese formula derived from Synopsis of the Golden Chamber , has been reported to have the effects of lowing hyperlipidemia and ameliorating NAFLD. Nevertheless, the underlying mechanism by which ZXD alleviates NAFL and NASH remains elusive. This study aims to explore the therapeutic role of ZXD in the process of NAFLD and elucidate the mechanism by which ZXD maintains lipid homeostasis in vivo and in vitro so as to provide a potential candidate for clinical treatment of NAFLD. Methods NAFL and NASH mice models introduced by high fat and high cholesterol diet (HFHCD) or methionine and choline deficient diet (MCD) were established and used to investigate the benefits of ZXD on the progress of NAFLD in vivo . Human hepatocellular carcinoma cell line (HepG2) and mouse alpha liver 12 cell line (AML12) were stimulated by oleic acid and palmitic acid (OPA) to induce lipid accumulation model in vitro . The levels of total cholesterol (TC), triglyceride (TG), nonesterified free fatty acids (NEFA), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) were measured by commercial kits. Hematoxylin and eosin (HE) staining, Oil Red O staining, Sirius red staining and immunofluorescence staining were applied to observe the liver lesions such as steatosis, inflammation, and fibrosis. Levels of interleukin-1 β (IL‑1 β ), IL-6 and tumor necrosis factor- α (TNF‑ α ) were detected by ELISA. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting analysis were conducted to detect the related mRNA and protein levels after ZXD intervention in both mice liver and