Ethanol induced adaptive changes in blood for the pathological and toxicological effects of chronic ethanol consumption in humans.

Alcohol consumption is associated with a number of toxicological changes in blood and the oxidant-antioxidant system. The present study was performed to investigate the alcohol induced toxicological, pathological changes in blood and an adaptive role of erythrocyte antioxidant system in chronic alcoholics. Human male volunteers aged 44±6 years with similar dietary habits were divided into two groups, namely non-alcoholic controls and chronic alcoholics. We measured hematological parameters, erythrocyte lipid peroxidation, NO production, erythrocyte antioxidant and liver function test enzyme activities. Alcoholics had increased erythrocyte nitric oxide levels and also elevated erythrocyte lipid malondialdehyde (MDA) concentrations. Strikingly, increments in reduced glutathione and markedly increased activities of certain antioxidant enzymes such as glutathione reductase (GR), superoxide dismutase (SOD), and another related enzyme G-6 phosphate dehydrogenase (G6-PDH) with no alterations in the activities of glutathione S-transferase (GST), glutathione peroxidase (GPx), and catalase (CAT) in chronic alcoholics were observed compared to controls. Furthermore, erythrocyte NO levels were positively correlated with lipid peroxidation, SOD, GSH, GR and G6PDH in chronic alcoholics. In addition, increased AST/ALT ratio and a significant increase in WBC and platelets were also noticed. Together, these results indicate that, antioxidants and defense enzymes appear to be rendering protection as a consequence of chronic adaptation in alcoholics.