Neuroprotective effect of the extract of Astragalus against amyloid β-protein-induced injuries in PC12 cells

Objective To observe the neuroprotective effect of the extract ofastragalus (EA) on cultured PC12 cells against amyloid β-protein (Aβ) -mediated cell toxicity and explore the possible mechanism. Methods PC12 cells were cultured in DMEM medium and treated with different concentrations(20,40,80 μg/mL) of EA after exposure to 10 μmol/L A[S. The survival rate of the cells was measured by MTT assay, and the accumulation of reactive oxygen species (ROS) in PC I2 cells induced by Aβ25-35 was detected by fluorometric method. TUNEL assay was performed to analyze the cell apoptosis. Results Compared with the model group, EA treated group significantly increased the cell survival rate, decreased ROS production in the cells and lowered the apoptosis rate of Aβ25-35-treated PC12 cells in a concentration-dependent manner (P<0.05). Conclusion EA may reduce the injuries of PC12 cells induced by Aβ25-35 exposure, which is associated with the dose-dependent anti-oxidative and anti-apoptotic activities of EA. Key words: Extract of astragalus; Alzheimer's disease; Beta-amyloid protein; Reactiveoxygen species