Rejuvenation of antioxidant and cholinergic systems contributes to the effect of procyanidins extracted from the lotus seedpod ameliorating memory impairment in cognitively impaired aged rats

The major purpose of this study was to determine the effect of procyanidins extracted from the lotus seedpod (LSPC) on the learning and memory impairments in cognitively impaired aged rats. Based on Morris water maze performance compared with young female rats, aged unimpaired (AU) and aged impaired (AI) rats were chosen from aged female rats. LSPC supplementation (50, 100 mg/kg BW, p.o.) for 7 weeks significantly improved learning and memory impairments in AI animals in the Morris water maze test, as evaluated by shortened escape latency and swimming distance. Aged rats had significantly declined antioxidant defense capacities and significantly increased lipid peroxidation and protein oxidation levels in hippocampus and cerebral cortex than young rats. Further, AI group had higher protein oxidation level compared with AU group. LSPC (50, 100 mg/kg BW, p.o.) significantly reversed the decline of antioxidant defense capacities and significantly reduced lipid peroxidation and protein oxidation levels in hippocampus and cerebral cortex of AI rats. In addition, LSPC significantly restored acetylcholine (ACh) contents and acetylcholinesterase (AChE) activities in hippocampus and cerebral cortex of AI animals. The results of this study suggest that LSPC may play a useful role in the treatment of cognitive impairment caused by Alzheimer's disease and aging.