Abstract:Objective: To investigate the role of "Sirt1-autophagy" on the hypoxia-induced apoptosis in OCCM-30 cementoblasts of mouse. Methods: OCCM-30 cells were cultured in vitro and were randomly divided into the control group, the hypoxia group, the hy-poxia + resveratrol group, the hypoxia + 3-MA group, the hypoxia + resveratrol + ex527 group and the hypoxia + resveratrol + 3-MA group. Changes of autophagy lysosomes in each group were observed by MDC staining and changes of autophagosome light chain Ⅱ (LC3 Ⅱ) were detected by immunofluorescence assay. The expression of Sirt1, LC3 Ⅱ and p62 proteins was detected by Western blot. Cell apoptosis was detected by flow cytometry. Results of different groups were analyzed by one-way ANOVA and different groups were analyzed by LSD-t. Results: Compared with the control group, the content of autophagy lysosomes (P=0.000) and the number of autophagosomes (P=0.000) in the hypoxia group were significantly increased, the expression of LC3 Ⅱ (P=0.001) protein was signifi-cantly increased, the expression of p62 protein was significantly decreased (P=0.000), and the apoptosis rate was increased (P=0.000). Compared with the hypoxia group, the number of autophagy lysosomes (P=0.019) and autophagosomes (P=0.000), and the expression of LC3 Ⅱ protein (P=0.000) and Sirt1 protein (P=0.049, P=0.000) in the hypoxia + resveratrol group were significantly increased, the expression of p62 protein (P=0.000) was signifi-cantly decreased, and the apoptosis rate was decreased (P=0.021). Compared with the hypoxia + resveratrol group, the number of autophagy lysosomes (P=0.000) and autophagosomes (P=0.000), and the expression of LC3 Ⅱ (P=0.000) and Sirt1 (P=0.000) in the hypoxia + resveratrol + ex527 group were sig-nificantly decreased, the expression of p62 protein (P=0.000) was significantly increased, and the apoptosis rate was increased (P=0.000). Compared with the hypoxia + resveratrol group, the num-ber of autophagy lysosomes (P=0.000) and autophagosomes (P=0.000), and the expression of LC3 Ⅱ (P=0.000) protein expression in the hypoxia + resveratrol + 3-MA group were significantly decreased, the expression of p62 protein (P=0.000) was increased, the apoptosis rate was increased (P=0.000), and the expression of Sirt1 protein (P=0.146) was decreased, with no statistically significant difference. Conclusion: Autophagy-related molecules may be downstream acting molecules of Sirt1 in the hypoxic environment and autophagy plays a protective role in hypoxia-induced apoptosis of OCCM-30.
