Alpha-lipoic acid treatment of acetaminophen-induced rat liver damage.

Acetaminophen (paracetamol) is a well-tolerated analgesic and antipyretic drug when used at therapeutic doses. Overdoses, however, cause oxidative stress, which leads to acute liver failure. Alpha lipoic acid is an antioxidant that has proven effective for ameliorating many pathological conditions caused by oxidative stress. We evaluated the effect of alpha lipoic acid on the histological and histochemical alterations of liver caused by an acute overdose of acetaminophen in rats. Livers of acetaminophen-intoxicated rats were congested and showed centrilobular necrosis, vacuolar degeneration and inflammatory cell infiltration. Necrotic hepatocytes lost most of their carbohydrates, lipids and structural proteins. Liver sections from rats pre-treated with lipoic acid showed fewer pathological changes; the hepatocytes appeared moderately vacuolated with moderate staining of carbohydrates and proteins. Nevertheless, alpha lipoic acid at the dose we used did not protect the liver fully from acetaminophen-induced acute toxicity.