Heteropteris aphrodisiaca O. Machado: Effects of extract BST 0298 on the oxidative stress of young and old rat brains

The plant Heteropteris aphrodisiaca O. Machado is widely employed in Brazil ian popular medicine as a stimulant, a tonic and a remedy for nervous debil ity. Several other plant products with similar therapeutic applications may have such effects based on the antioxidant content of polyphenols (gallate s, cathecols, etc.) and flavonoids. The aim of this work was to investigate the effects of Heteropteris aphrodisiaca O. Machado extracts on the antiox idant defences and oxidative stress of young and old rat brains. Tests of l ipoperoxidation in vitro, comparing H. aphrodisiaca extracts with butylhydr oxytoluene (BHT), a classic antioxidant, showed an efficient inhibition of lipoperoxidation (Q(1/2) = 3.3 mug/mL). Chronic treatment of young and old rats with 50 mg plant extract/kg body weight resulted in a significant incr ease in superoxide dismutase (SOD) activities (40%) in the brain of old rat s, but no changes in catalase and glutathione peroxidase (GPX). No signific ant variations in antioxidant enzyme activities were observed in the brains of young rats. However, significantly lower levels of lipoperoxidation (30 %) were detected in the brain of young rats upon plant extract administrati on, suggesting that H. aphrodisiaca extracts reduced the oxidative stress t o brain lipids. Copyright (C) 2001 John Wiley & Sons, Ltd.