动物造模 z-bio 2022-10-19 337

　　Objective To investigate the protective effect and mechanism of estrogen on oxidative stress injury of mouse osteoblast MC3T3-E1.

　　Methods MC3T3-E1 cells were divided into blank control group and H2O Group (300 μ Mol/L), H2O2+estrogen 0.1 μ Mol/L group, H, O2+estrogen 1 μ Mol/L group, H, O,+estrogen 10 μ The mol/L group and H, O,+NAC 1 mmol/L group were incubated with drugs of corresponding concentration respectively. CCK-8 was used to detect cell proliferation activity, flow cytometry was used to detect apoptosis rate and mitochondrial membrane potential; The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were detected with the kit; The level of reactive oxygen species (ROS) was detected by fluorescence probe; The protein expression of Smad5, Runx2, Bax, Bcl-2 and cleaved Caspase-3 was detected by Western Blot.

　　Results Compared with the blank control group, the proliferation activity of osteoblasts in H, O, group decreased significantly (P<0.05), the apoptosis rate and JC-1 positive cell rate increased significantly (P<0.05), the MDA and ROS levels increased significantly (P<0.05), the SOD activity decreased significantly (P<0.05), the expression of Smad5, Runx2 and Bcl-2 proteins decreased significantly (P<0.05), and the expression of Bax and cleaved Caspase-3 proteins increased significantly (P<0.05); Compared with H, 0. group, H, O0,+estrogen 1 μ Mol/L group, H, O,+estrogen 10 μ The proliferation activity of cells in the mol/L group and H, O,+NAC 1mmol/L group increased significantly (P<0.05), the apoptosis rate and JC-1 positive cell rate decreased significantly (P<0.05), the MDA and ROS levels decreased significantly (P<0.05), the SOD activity increased significantly (P<0.05), the expression of Smad5, Runx2 and Bcl-2 protein increased significantly (P<0.05), and the expression of Bax and cleaved Caspase-3 protein decreased significantly (P<0.05).

　　Conclusion Estrogen may reduce the ROS level of MC3T3-E1 cells damaged by oxidative stress by activating the expression of Smad5/Runx2 signal axis, and improve the differentiation ability of MC3T3-E1 cells.