Abstract: AIM: To investigate the effect and molecular mechanism of Phellodendron amurense extract on hippocampal nerve cells induced by Aβ1-42. METHODS: Isolate and culture hippocampal nerve cells and divide them into control group, model group, model+Phellodendron amurense low, medium and high concentration group, model+si-NC group, model+si-XIST group, model+Phellodendron amurense high concentration+pcDNA group, model+ Phellodendron amurense high concentration+pcDNA-XIST group. The cell viability was detected by MTT; the cell cycle and apoptosis were detected by flow cytometry; the protein expression of Cleaved-caspase3 was detected by Western blot; the expression level of XIST was detected by RT-qPCR.RESULTS: In the model group, the cell survival rate and the proportion of cells in S phase decreased, while the proportion of cells in G0-G1 phase, the expression level of XIST, the apoptosis rate, and the expression level of Cleaved-caspase3 increased (P<0.05). After treatment with different concentrations of Phellodendri amurense extract and inhibiting the expression of XIST, the cell survival rate and the proportion of cells in the S phase increased, while the proportion of cells in the G0-G1 phase, the expression level of XIST, the apoptosis rate, and the expression level of Cleaved-caspase3 decreased (P<0.05). Overexpression of XIST weakened the effect of Phellodendron amurense extract on cell proliferation and apoptosis of hippocampal neuronal induced by Aβ1-42.CONCLUSION: The extract of phellodendron amurense extract may inhibit apoptosis of Aβ1-42-induced hippocampal neurons, which may be related to down-regulation of XIST.

Key words: phellodendron amurense extract, XIST, Alzheimer's disease, hippocampal nerve cells, apoptosis