Asiatic Acid from Potentilla chinensis Attenuate Ethanol-Induced Hepatic Injury via Suppression of Oxidative Stress and Kupffer Cell Activation

This study examined the effect of Asiatic acid from Potentilla ehhzensis (AAPC) on chronic ethanol-induced hepatic injury. Rats underwent intragastric administration of ethanol (5.0-9.0 g/kg) once a day for 12 weeks. A subset of rats were also intragastrically treated with AAPC (2, 4 or 8mg/kg) once a day. In the end, AAPC treatment significantly protected against ethanol-induced liver injury, as evidenced by the decrease in serum alanine and aspartate aminotransferases levels and the attenuation of histopathological changes in rats. Additionally, AAPC significantly decreased blood alcohol and acetaldehyde concentrations by enhancing alcohol dehydrogenase and aldehyde dehydrogenase activities. Mechanistically, studies showed that AAPC remarkably alleviated the formations of malondialdehyde and myeloperoxidase, restored impaired antioxidants, including superoxide dismutase, glutathione peroxidase, glutathione reductase and catalase, and inhibited cytochrome P450 (CYP)2E1 activity. Moreover, the over-expression of cytokines, such as tumor necrosis factor (TNF)-alpha, interleukin (IL)-1 beta, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the elevated plasma endotoxin level and the up-regulated Toll-like receptor 4 (TLR4), CD14 and myeloid differentiation factor 88 (MyD88) as well as nuclear factor-kappa B were also suppressed by AAPC in ethanol-intoxicated rats. In conclusion, the protective effect of AAPC on ethanol-induced hepatotoxicity was mainly due to its ability to attenuate oxidative stress and inhibit Kupffer cell activation by decreasing the level of plasma endotoxin and the expression of TLR4, CD14 and MyD88.