Effect of acute administration of hydroalcohol extract of Ilex paraguariensis St Hilaire (Aquifoliaceae) in animal models of Parkinson's disease

Ilex paraguariensis St Hilaire (Aquifoliaceae) is a plant widely cultivated in South America and with various reputed medicinal properties that can be attributed to phenolic constituents of the leaves: caffeine, theophylline and theobromine, besides the flavonoids, quercetin and rutin. This study examined the antiparkinsonian activity of the hydroalcohol extract of Ilex paraguariensis in models of protection against cerebral injury induced by MPTP and reversal of the catatonia induced by reserpine in mice. The hydroalcohol extract prevented MPTP‐induced hypolocomotion at doses of 250 and 500 mg/kg at the all time points observed and also prevented the reserpine‐induced catalepsy at the same doses. The extract potentiated the effect of apomorphine in preventing catatonia, suggesting a non‐dopaminergic activity, probably through antagonism of adenosine. In biochemical studies the hydroalcohol extract caused a significant decrease in the NO levels, exhibited a DPPH‐scavenging ability and was effective in preventing the oxidation of deoxyribose. The results obtained suggest that the hydroalcohol extract of Ilex paraguariensis may have an antiparkinsonian profile in animal models, probably through its antioxidant activity and antagonist action on adenosine A2A receptors. Copyright © 2007 John Wiley & Sons, Ltd.