Abstract:
OBJECTIVE To observe the effect of dihydromyricetin(DMY) on dexamethasone(DEX)-induced ferroptosis in osteoblast line MC3T3-E1 cells and explore its mechanism.
METHODS MC3T3-E1 cells were cultured in α-MEM medium. The experiment was divided into control group, DEX(10 μmol·L−1) group, DMY(20 μmol·L−1), DEX+DMY group, ferroptosis inducer RSL3 group, DEX+DMY+RSL3 group, nuclear factor E2 related factor-2(Nrf2) inhibitor ML385(5 μmol·L−1) group, DEX+DMY+ML385 group. Cell viability was detected by thiazolyl blue tetrazolium bromide(MTT) method. The levels of total iron ions and divalent iron ions, malondialdehyde(MDA), glutathione(GSH) and reactive oxygen species(ROS) in cells were detected by kit. The transmission electron microscope was used to test the ultrastructure of the cells. The expression levels of glutathione peroxidase 4(GPX-4), heme oxygenase 1(HO-1) and Nrf2 proteins were detected by Western blotting.
RESULTS Compared with the DEX group, the cell viability, GSH concentration and expression of GPX4 protein in MC3T3-E1 cells in the DEX+DMY group increased significantly(P<0.05), the mitochondrial damage of cells was significantly reduced, and the levels of total iron ions, ferric ions, ROS and MDA in the cells decreased significantly(all P<0.05). Compared with the DEX+DMY group, the cell viability of MC3T3-E1 cells in the DEX+DMY+RSL3 group was significantly reduced(P<0.05). Compared with the DEX group, the expression level of Nrf2 in the nucleus, the ratio of Nrf2 expression in the nucleus to the expression of Nrf2 total protein, and the protein expression level of HO-1 in the DEX+DMY group were significantly increased(all P<0.05). Compared with the DEX+DMY group, the cell viability and GSH concentration of MC3T3-E1 cells in the DEX+DMY+ML385 group were significantly reduced(P<0.05), and the levels of total iron ions, divalent iron ions, ROS and MDA in the cells were significantly increased(P<0.05).
CONCLUSION DMY inhibits DEX induced ferroptosis in osteoblasts, and its mechanism may be through Nrf2/HO-1 signaling pathway.