Chlorogenic Acid Protects against Advanced Alcoholic Steatohepatitis in Rats via Modulation of Redox Homeostasis, Inflammation, and Lipogenesis

The aim of this study was to evaluate the therapeutic effects of chlorogenic acid (CGA) in rats with advanced alcoholic steatohepatitis. The rats were fed on a high-fat diet and gavaged with ethanol (4 g/kg) for 8 weeks. The livers of ethanol-treated rats showed steatosis; necrosis and mononuclear infiltration; and significant upregulation of the mRNA expression of the prooxidant (Cyp2e1, iNos), lipogenic (Srebp1, Acc), proinflammatory (Tlr4, Nf-κb, TnfA, Il-1B, and Il-6), and profibrogenic (TgfB, Col1, VegfA) genes. Simultaneously, a downregulation of level of Sod and Nrf2 was observed, which was accompanied by increased serum transaminase, TnfA, and serum and liver triglycerides levels. CGA administration (40 and 80 mg/kg, 8 weeks) to ethanol-fed group reduced the liver expression levels of Cyp2e1 and iNos, whereas it markedly enhanced the expression of Sod, Nrf2, and Ho-1. CGA at both doses downregulated the expressions of lipogenic, proinflammatory, and profibrogenic genes, while the expression of Tlr4 was lowered only after the higher dose of CGA. The higher dose of CGA efficiently prevented the progression of alcohol-induced steatosis and reduced inflammation through regulation of the expression of genes encoding the proteins involved in the Tlr4/Nf-κB signaling pathway and fibrosis. The study revealed hepatoprotective and anti-inflammatory effects of CGA through the regulation of expression of genes encoding Cyp2e1/Nrf2 involved in oxidative stress modulation. These results demonstrate CGA as a therapeutic candidate for the prevention and treatment of alcoholic steatohepatitis.