A Herbal Formulation of Danshen and Gegen Protects Rat Brains from Injuries Induced by Focal and Global Ischaemia

Background: Ischaemic stroke is a disease that affects many people in developed countries. The occurrence of this disease is also rising globally. Danshen and Gegen are two commonly used Chinese herbal medicines for the treatment of cardiovascular diseases. This study investigates the efficacy of a combined formulation of Danshen and Gegen (DG) in protecting the rat brains from damages induced by global and focal brain ischaemia. Methods: Global brain ischaemia in the rat was induced by 10 min bilateral common carotid artery occlusion with hypotension followed by 24 h reperfusion, and focal brain ischaemia was induced by 90 min middle cerebral artery occlusion (MCAO) followed by 24 h reperfusion. Results: Global ischaemia in the rat brain produced elevated levels of nitrite and malondialdehyde, and decreased the activities of the anti-oxidant enzymes superoxide dismutase, catalase, and reduced glutathione. Daily oral administration of DG (0.3 g/kg and 3 g/kg) for 7 days prior to the induction of global ischaemia produced dose-dependent suppression on the production of nitrite and malondialdehyde, and restored activities of the anti-oxidant enzymes. Rat brains subjected to focal ischaemia showed increased brain infarct size, infarct weight, and neurological deficit. These detrimental changes were markedly attenuated by the same pretreatment protocol with DG (3 g/kg). Conclusion: The present DG formulation was found to possess anti-nitrative and anti-oxidative stress activities that could suppress ischaemia-induced damages in the rat brain. Therefore, the combined use of Danshen and Gegen for treatment of ischaemic stroke is favourable.