Autophagy Of Osteosarcoma MG63 Cells Induced By Aloe Emodin-Mediatd Photo- Dynamic Therapy

ObjectiveTo investigate the relationship between autophagy and apoptosis induced by aloe emodin-mediated photodynamic therapy in osteosarcoma MG63 cells.MethodsThe cultured cells were divided into 4 groups:control group, AE group, LED group and AE-PDT group. MG63 cells were treated with aloe emodin combined with photodynamic therapy. The viability of cells was measured by CCK-8. The DCFH-DA probe was used to detect cell ROS level. The expression of autophagy was examined by MDC staining and electron microscope. The apoptosis of MG63 cells was detected by flow cytometry. The autophagy-related protein expressions of LC3 and Beclin-1 were assessed by Western bloting.ResultsPhotosensitizer aloe emodin-mediated PDT significantly suppressed cell viability in a photosensitizer concentration-and energy density-dependent manner. Compared with control group, the ROS level and autophagosomes were significantly increased in AE-PDT group. Typical autophagosome could be found under the electron microscopy. AE-PDT could induce-autophagy and apoptosis. The apoptosis rate was increased when autophage was inhibited by 3-MA. The results of Western bloting analysis showed that ratios of LC3-Π/LC3-I and Beclin-1/β-actin in AE-PDT group were higher than those in the single AE treatment group, the single light irradiation group and the empty control group.ConclusionsAE-PDT can induce autophagy in the MG63 cells. At the early stage of AE-PDT treatment, autophagy can postpone apoptosis to protect cells.