Modulation of the oxidative stress by metformin in the cerebrum of rats exposed to global cerebral ischemia and ischemia/reperfusion

Abstract

Objectives: Oxidative stress plays a major role in the pathogenesis of ischemic and reperfusion injury to many organs, including the brain. Chronic metformin treatment is associated with a lower risk of stroke in clinical populations. The aim of the present study was to investigate the effect of metformin on the oxidative stress induced in experimental model of incomplete global cerebral ischemia and ischemia/reperfusion in adult male Wistar rats.

Materials and methods: Metformin was administered to rats orally by gavage 500 mg/kg once daily for one week before induction of cerebral ischemia (rats were subjected to 30 min of ischemia before decapitation) and ischemia/reperfusion (rats were subjected to 30 min of ischemia then 60 minutes of reperfusion before decapitation). The selected parameters for oxidative stress were the activities of the antioxidant enzymes: glutathione peroxidase (GSHPx), superoxide dismutase (SOD), and catalase as well as malondialdehyde (MDA) levels.

Results: Metformin reduced the elevated activites of GSHPx, SOD and catalase as well as MDA levels in cerebrum of rats exposed to ischemia and ischemia/reperfusion injures.

Conclusions: Metformin improved the oxidative stress induced by ischemia and ischemia/reperfusion injuries. This may be a mechanism that explains the cerebroprotective effect of the drug.