Pyrola incarnata demonstrates neuroprotective effects against β-amyloid-induced memory impairment in mice

This study aims to investigate the neuroprotective effects of Pyrola incarnata against beta-amyloid-induced memory impairment in mice. Ethanol extract of Pyrola incarnata (EPI) was obtained and led to eleven phytochemicals successfully by isolation and purification, which were elucidated by spectroscopic analysis (H-1 NMR, C-13 NMR and HR-ESI-MS). Thereinto, ursolic acid was gained as most abundant monomer. C57BL/6 mice were intracerebroventricular injected with aggregated A beta(25-35). Open-field test, Barnes maze test and Morris water maze were conducted for evaluating cognition processes of EPI and ursolic acid. EPI significantly improved learning and memory deficits, attenuated the A beta(25-35) level of deposition immunohistochemically. Further studies revealed that ursolic acid as bioactive phytochemical of P. incarnata improved spatial memory performance and ameliorated A beta(25-35 )accumulation by activating microglia cells and up-regulating Ibal level in the hippocampus. These findings suggest P. incarnata could improve the cognition of mice and be a promising natural source for the treatment of neurodegenerative disease.