【Animal Modeling】-Protective effect and mechanism of estrogen on oxidative stress injury of mouse osteoblast MC3T3-E1

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

  Methods The MC3T3-E1 cells cultured in vitro were divided into blank control group, H2O. group (300 μmol/L), H2O2 + estrogen 0.1 μmol/L group, H, O2 + estrogen 1 μmol/L group, H, O, + estrogen Hormone 10 μmol/L group and H, O, + NAC 1 mmol/L group were incubated with corresponding concentrations of drugs, respectively. Cell proliferation activity in each group was detected by CCK-8, apoptosis rate and mitochondrial membrane potential were detected by flow cytometry; malondialdehyde (MDA) and superoxide dismutase (SOD) levels were detected by kits; cells were detected by fluorescent probe method Reactive oxygen species (ROS) levels; Western Blot detection of Smad5, Runx2, Bax, Bcl-2, cleaved Caspase-3 protein expression.

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

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