Neuroprotection of Glycyrrhizin against Ischemic Vascular Dementia in Vivo and Glutamate-induced Damage in Vitro

Objective To evaluate the neuroprotective effects of glycyrrhizin(GL) on vascular dementia(VaD) in vivo and Glutamate-induced damage in vitro.Methods Male Wistar rats were subjected to permanent occlusion of the bilateral common carotid arteries.On d 15 postsurgery,rat cognition was assessed using the Morris water maze.The activity of superoxide dismutase and the content of malondialdehyde of brains were also measured.Brain damage was evaluated histologically using HE staining.In vitro cell viability was examined in PC12 cells exposed to Glutamate,and mRNA levels of Bcl-2 and Bax were assessed.Results GL(20 mg/kg for 12 d) improved the performance of learning and memory of VaD rats,decreased the level of lipid peroxidation,and attenuated the pathological alterations in the hippocampal CA1 and CA3 areas.Moreover,GL(0.6 mmol/L) could protect PC12 cell lines from injury induced by Glutamate(10 mmol/L) and inhibit apoptosis of neuronal cells.Conclusion The present findings suggest that GL may have therapeutic potential in treating VaD.