Abstract

This study aimed to investigate the in vitro antioxidant activity of the novel anticonvulsant levetiracetam and benzodiazepine clonazepam. To do this, the mice brain homogenates were incubated with levetiracetam (50, 100 or 200 g/ml) or clonazepam (50, 100 or 200 g/ml), and then, submitted to heating at 37°C for 1 h. Ascorbic acid (vitamin C, 200 g/ml) was used as reference antioxidant drug. The markers of oxidative stress, such as lipid peroxidation, nitrite-nitrate content, catalase activity, and reduced glutathione (GSH) levels, were measured in brain homogenates. The group submitted to the heating-induced oxidative stress showed an increase in lipid peroxidation, nitrite-nitrate content, and catalase activity. Previous incubation with levetiracetam and clonazepam, mainly at lower doses (50 and 100 g/ml), and similarly to vitamin C, prevented these pro-oxidative changes, reducing the lipid peroxidation, nitrite-nitrate contents and catalase activity, and increasing GSH levels. These findings demonstrate antioxidant properties of levetiracetam and clonazepam, and help to elucidate the role of protection against oxidative stress in the neuroprotective mechanism of antiepileptic drugs.

Key words: Levetiracetam, clonazepam, oxidative stress, vitamin C, antiepileptic drugs.