Protective effect of tenuigenin on cytotoxicity of primary cultures of cortical neurons induced by amyloid beta-protein 1-40(Aβ_(1-40))

Objective: To observe the effect of tenuigenin(TEN) on aggregated amyloid beta-protein 1-40(Aβ1-40)-induced cytotoxicity of primary cultural cortical neurons in vitro.Method: In order to establish neurotoxic model,the primary cultural rat cortical neurons were treated with 25 μmol·L-1 aggregated Aβ1-40,which were divided into a model group and 3 different dose groups of TEN(50,100,200 μmol·L-1,respectively),and a normal control group with no treatment of Aβ1-40 was set up.The morphological changes of the neurons before and after administration of TEN were examined under a phase contrast microscope.Neuronal viabilities were detected by MTT colorimetry.Injuring degrees of the neuronal membrane were assessed by lactate dehydrogenase(LDH) colorimetry.Result: As compared with the normal control,treatment of primary cultural neurons with Aβ1-40(25 μmol·L-1) for 24 h caused a significant decrease in viabilities and morphological changes of nerve cells,with neurons losing adherent ability or shedding,and the synapse shortening found by microscope.The percentage of apoptotic nerve cells and the LDH leakage were significantly decreased,and the survival rate of neurons was significantly increased in both the TEN high and medium dose groups.Conclusion: The aggregated Aβ1-40 has a definite neurotoxicity for cultural cortical neurons,and TEN can significantly protect the neurons from the cytotoxicity of Aβ1-40.