Influence of thioctic acid (alpha-lipoic acid) on N-nitroso-diethylamine-induced carcinogenesis in male sprague-dawley rats.

Male Sprague-Dawley rats received 10 mg/kg body weight of N-nitroso-diethylamine by gavage twice weekly for life (group 1). An additional daily application of thioctic acid (alpha-lipoic acid) in drinking water (45 mg/kg body weight/day) (group 2) and 180 mg/kg body weight/day (group 3) did not significantly influence tumor frequencies, induction times and histology of the induced liver and esophageal tumors. A postulated enhancing mechanism on tumor development due to thioctic acid treatment could not be demonstrated.