Panax ginseng ginsenoside-Rg2 protects memory impairment via anti-apoptosis in a rat model with vascular dementia

Ethnophamacological relevance: Ginsenosides, the major active ingredients of Panax ginseng, produce a variety of pharmacological or physiological responses with effects on the central and peripheral nervous systems. Aim of the Study: In this report, we investigated the effects of ginsenoside Rg(2) on cerebral ischemia-reperfusion induced impairment of neurological responses, memory and caudate-putamen neuronal apoptosis in a vascular dementia (VD) rat model. Materials and Methods: Neurological evaluation was performed 24 h after reperfusion and Y-maze memory performance was assessed at 48 h after reperfusion. Immunocytochemical techniques were employed to check the protein expression of BCL-2, BAX, heat shock protein 70 and P53, which are related with cell apoptosis. Results: Neurological responses and memory ability of the ginsenoside Rg(2) or nimodipine groups improved significantly compared with the VD group. The expression of BCL-2 and HSP70 were decreased, while BAX and P53 were increased in the VD model. The expression of BCL-2 and HSP70 proteins were increased, while BAX and P53 decreased after ginsenoside Rg(2) (2.5, 5 and 10 mg/kg) and nimodipine (50 mu g/kg) treatment compared with the VD group. The study suggests that ginsenoside R92 improved neurological performance and memory ability of VD rats through mechanisms related to anti-apoptosis. Conclusions: The capacity for ginsenoside Rg(2) to modulate the expression of apoptotic related proteins suggests that ginsenoside Rg(2) may represent a potential treatment strategy for vascular dementia or other ischemic insults. (c) 2007 Elsevier Ireland Ltd. All rights reserved.