Polydatin protects learning and memory impairments in a rat model of vascular dementia.

Polydatin is one of the most common encountered stilbenes of nature and a key component of the Chinese herb Polygonum cuspidatum. This study is to investigate the effects of polydatin on learning and memory impairments induced by chronic cerebral hypoperfusion in rats, as well as the potential mechanism. Both common carotid arteries and both vertebral arteries occlusion (four-vessel occlusion, 4-VO) induced severe cognitive deficits tested by water maze task, along with oxidative stress in hippocampus. Oral administration of polydatin for 30 days markedly attenuated cognitive deficits compared with the control (p < 0.05). Biochemical determination revealed that polydatin decreased the production of malondialdehyde (MDA) and significantly increased the activities of superoxide dismutase (SOD) and catalase (CAT). Additionally, polydatin effectively alleviated the injuries of cultured neurons induced by oxygen-glucose deprivation (OGD). These results suggest that polydatin exhibit therapeutic potential for vascular dementia, which is most likely related, at least in part, to its anti-oxidant activity and the direct protection of neurons.