Impact of massive ascorbic acid supplementation on alcohol induced oxidative stress in guinea pigs

The effects of a mega dose of ascorbic acid (AA) on alcohol induced peroxidative damages were investigated in guinea pigs, In the present study, four groups of male guinea pigs were maintained for 30 days as follows. (1) Control group (1 mg AA/100 g body wt); (2) Ethanol group (1 mg AA/100 g body wt. +9 g ethanol/kg body wt); (3) AA group (25 mg AA/100 g body wt); (4) AA + ethanol group (25 mg AA/100 g body wt. + 9 g ethanol/kg). Results revealed that alcohol induced significant lipid peroxidation, since the lipid peroxidation products malondialdehyde (MDA), hydroperoxides and conjugated dienes were elevated. The activities of scavenging enzymes superoxide dismutase (SOD), catalase were reduced. However, supplementation of AA along with alcohol reduced the lipid peroxidation products in the liver and enhanced the activities of scavenging enzymes. Activities of glutathione peroxidase and reductase were also greater in guinea pigs given alcohol + AA in comparison with those given alcohol alone. Administration of ascorbic acid also reduced the activity of gamma-glutamyl transpeptidase (GGT), the marker enzyme of alcohol induced toxicity. The vitamin E level, which was reduced by alcohol intake, was raised by the co-administration of AA and alcohol. These studies suggest that a mega dose of AA helps in the prevention of alcohol induced oxidative stress by enhancing the antioxidant capacity and also by reducing the lipid peroxidation products. (C) 1999 Elsevier Science ireland Ltd. All rights reserved.