Investigation of the possible protective role of gallic acid on paraoxanase and arylesterase activities in livers of rats with acute alcohol intoxication

Gallic acid, a polyphenyl class natural product from gallnut and green tea, is known to be antioxidant, anti‐inflammatory and radical scavenger. In this study, we aimed to investigate the possible protective effects of gallic acid on paraoxonase and arylesterase activities in liver exposed to acute alcohol intoxication. Paraoxonase and arylesterase activities in liver tissue and serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were measured. Histological investigations were also made. In our study, we observed a significant increase of serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, which are indicators of liver damage after acute ethanol consumption. Gallic acid therapy has significantly reduced the increase in these biomarkers, indicating a possible hepatoprotective effect of gallic acid. Ethanol consumption caused a significant decrease in liver paraoxonase activity (P < 0.001). Gallic acid treatment partly restored this decreased paraoxonase activity, which resulted from ethanol administration. A gallic acid dose of 100 mg/kg was observed as highest restoring effect for paraoxonase activity (P < 0.05). The activity of arylesterase was decreased in the ethanol group as compared with the control group, but this was not significant. However, 50 mg/kg of gallic acid treatment restored the loss of this activity due to ethanol exposure (P < 0.001). We observed that gallic acid ameliorates the liver damage caused by excessive alcohol consumption in a dose‐dependent way. Our results in this study showed that gallic acid might have a protective effect against alcoholic liver disease. Copyright © 2012 John Wiley & Sons, Ltd.