Puerarin attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice

Puerarin (PUE), an isoflavone purified from the root of Pueraria lobata (Chinese herb), has been reported to attenuate learning and memory impairments in the transgenic mouse model of Alzheimer's disease (AD). In the present study, we tested POE in a sporadic AD (SAD) mouse model which was induced by the intracerebroventricular injection of streptozotocin (STZ). The mice were administrated PUE (25, 50, or 100 mg/kg/d) for 28 days. Learning and memory abilities were assessed by the Morris water maze test. After behavioral test, the biochemical parameters of oxidative stress (glutathione peroxidase (GSH-Px), superoxide dismutases (SOD), and malondialdehyde (MDA)) were measured in the cerebral cortex and hippocampus. The SAD mice exhibited significantly decreased learning and memory ability, while POE attenuated these impairments. The activities of GSH-Px and SOD were decreased while MDA was increased in the SAD animals. After POE treatment, the activities of GSH-Px and SOD were elevated, and the level of MDA was decreased. The middle dose PUE was more effective than others. These results indicate that POE attenuates learning and memory impairments and inhibits oxidative stress in STZ-induced SAD mice. POE may be a promising therapeutic agent for SAD. (C) 2015 Elsevier Inc. All rights reserved.