LONG-TERM ETHANOL ADMINISTRATION ENHANCES URINARY ULTRAWEAK LUMINESCENCE AND AGE-DEPENDENT MODULATION OF REDOX IN CENTRAL AND PERIPHERAL ORGANS OF THE RAT

Numerous experimental evidence sustains a pathogenic role for oxidativ e stress in aging. Acute and chronic ethanol metabolism is also known to be associated with oxidative perturbation of cellular oxidant/antio xidant balance. In the present work we investigated the effects of 25 months of ethanol consumption on the antioxidant defense system in dif ferent organs of rats, in comparison with normal and aged animals. We show that aged rats underwent a significant perturbation of the antiox idant defense system, as indicated by depletion of reduced glutathione content, increases in oxidized glutathione and free radical-induced u rinary luminescence associated with a decrease of glutathione reductas e and increase of glutathione transferase activities. These modificati ons, observed particularly in the liver and brain, were enhanced by lo ng-term alcohol exposure. Our results indicate that increased glutathi one transferase activity and decreased glutathione reductase activity, followed by thiol depletion, are important factors sustaining a patho genic role for oxidative stress in aging and in all situations where a ge-correlated changes occur. They also reinforce the oxidative potenti al of toxic compounds, such as ethanol intoxication.