Improvement Effect Of Fructus Broussonetae Extract On Endoplasmic Reticulum Stress Cell Model Induced By Tunicamycin And Its Molecular Mechanism

OBJECTIVE: Effect and molecular mechanism of Fructus Broussonetia extract on endoplasmic reticulum stress(ERS)model induced by tunicamycin.Method: The endoplasmic reticulum stress model was induced by the intervention of tunicamycin to PC12 cells.The model cells were divided into model group,high Chinese medicine dose group,medium Chinese medicine dose group and low Chinese medicine dose group.Each Chinese medicine dose group was incubated with different concentration of fructus broussonetae medicated serum.Utilization of CCK8 method to detect the survival rate of PC12 cells in each group.And cell cycle and apoptosis rate were detected by flow cytometry.Usage of immunoblotting to detect the expression of apoptosis related protein GRP78 and Caspase-12.Resule: The survival rate of each group of fructus broussonetae medicated serum was significantly higher than that of the model group(P< 0.05).The ratio(19%)of G2 phase cells in the cell cycle of the high dose of fructus broussonetae medicated serum group was significantly higher than that(6.9%)of the G2 phase in the cell cycle of the model group.The apoptosis rate of the model group was 8.36%,and the apoptosis rate of the intervention cells in the high dose group decreased to 4.51%,and the difference was significant(P< 0.05)compared with the model group.The expression of apoptosis related protein GRP78 and Caspase-12 in the high dose group of Chinese medicine was significantly lower(P< 0.05)than that of the model group.Conclusion: Fructus broussonetae can effectively improve the cytotoxicity induced by tunicamycin and increase cell cycle arrest.Its mechanism may be through cell cycle retardant,repair of damaged cells during G2 phase,alleviate the progress of endoplasmic reticulum stress and then inhibit cell apoptosis.