Effect of baicalin on toll-like receptor 4-mediated ischemia/reperfusion inflammatory responses in alcoholic fatty liver condition

Alcoholic fatty liver is susceptible to secondary stresses such as ischemia/reperfusion (I/R). Baicalin is an active component extracted from Scutellaria baicalensis, which is widely used in herbal preparations for treatment of hepatic diseases and inflammatory disorders. This study evaluated the potential beneficial effect of baicalin on I/R injury in alcoholic fatty liver. Rats were fed an alcohol liquid diet or a control isocaloric diet for 5 weeks, and then subjected to 60 min of hepatic ischemia and 5 h of reperfusion. Baicalin (200 mg/kg) was intraperitoneally administered 24 and 1 h before ischemia. After reperfusion, baicalin attenuated the increases in serum alanine aminotransferase activity, tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6) levels in alcoholic fatty liver. The increased levels of INF-alpha and IL-6 mRNA expression and inducible nitric oxide synthase and cyclooxygenase-2 protein and mRNA expressions increased after reperfusion, which were higher in ethanol-fed animals, were attenuated by baicalin. In ethanol-fed animals, baicalin attenuated the increases in toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 protein expressions and the nuclear translocation of NF-kappa B after reperfusion. In conclusion, our findings suggest that baicalin ameliorates I/R-induced hepatocellular damage by suppressing TLR4-mediated inflammatory responses in alcoholic fatty liver. (C) 2011 Published by Elsevier Inc.