Abstract: Objective To investigate the therapeutic effects of quercetin on non-alcoholic steatohepatitis (NASH) in rats, and the effects of quercetin on expressions of nuclear factor-κB (NF-κB). Methods The rats were fed with a high-fat diet for 6 weeks to induce NASH. The NASH model rats were given by gavage with quercetin 40-160 mg/kg for 4 weeks. The levels of serum total cholesterol (TC), triglycerides (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured by the automatic blood chemical analyzer. The protein expressions of NF-κB in the hepatic tissues were detected by western blotting while tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6) and interleukin-1β(IL-1β) mRNA by RT-PCR. Results Compared with control groups, the serum levels of LDL-C, TC and AST were decreased significantly in the quercetin-treated groups. Oral administration of quercetin improved hepatic steatosis and inflammatory cell infiltration effectively in NASH rats, reduced the mRNA expressions of TNF-α, IL-6 and IL-1β, and down-regulated the protein expression of NF-κB, with a dose-dependent trend which can be observed. Conclusion Quercetin had significant therapeutic benefits to prevent NASH through inhibiting hepatic lipid accumulation, that may be works through regulating NF-κB pathway.

Key words: Quercetin, Non-alcoholic steatohepatitis (NASH), Nuclear factor-κB (NF-κB), Inflammation, Hyperlipoidemia