Polysaccharide ofTaxus chinensisvar.maireiCheng et LKFu attenuates neurotoxicity and cognitive dysfunction in mice with Alzheimer's disease

Context Polysaccharide ofTaxus chinensisvar.maireiCheng et L.K.Fu (Taxaceae) (PTM) functions in anti-apoptosis and antioxidation, but its function on Alzheimer's disease (AD) remains unclear. Objective To investigate the effect of PTM on AD. Materials and methods C57BL/6J mice were randomly divided into three groups: control,d-galactose (d-gal), andd-gal + PTM. AD-like symptom was induced byd-gal for 6 weeks, followed with PTM (0.4 g/kg/d) for 14 days. PTM was added to BV2 cells stimulated withd-gal (1, 10, 20, 50, 100 and 500 mu g/mL). Cell viability was evaluated by MTT assay. The expression of NRF2, SOD, cleaved caspase-3, Bax and Bcl-2 were detected with Western blot analysis. Cognitive function was evaluated by Morris water maze test. Results Decreased cleaved caspase-3 (1.30 +/- 0.09) and Bax/Bcl2 ratio (1.32 +/- 0.11) were observed in BV2 cells induced byd-gal + PTM (50 mu g/mL). Increased MDA and ROS and decreased SOD were observed ind-gal group. However, decreased MDA (175 +/- 9 ng/mL) and ROS level (188 +/- 38 ng/mL) were observed after treated with PTM group (p < 0.05). In addition, the expression of NRF2 decreased ind-gal group (0.75 +/- 0.09) but increased after treated with PTM (p < 0.05). Furthermore, decreased A beta 1-42 was observed and the cognitive function was improved after PTM intervention (p < 0.05). Conclusions This is the first report that PTM inhibited oxidative stress and apoptosis in AD. The result will further accelerate the applications ofTaxus chinensisvar.maireiand the treatment for AD.