Radiation Induces Apoptosis and Osteogenic Impairment through miR-22-Mediated Intracellular Oxidative Stress in Bone Marrow Mesenchymal Stem Cells

Figure 1

Cellular apoptosis and ROS generation following IR (0 or 6 Gy) in rBMSCs. N-Acetyl-L-cysteine (NAC) is a classical antioxidant, which was used to testify the relationship of ROS generation with apoptosis in our experiment. (a) Cellular apoptosis was measured at 24 h postradiation by using the Annexin V-FITC method. IR-induced apoptosis can be partly rescued by pretreatment with NAC (). (b–d) Detection of ROS level at 24 h postradiation, (b) ROS staining with Fluorometric Intracellular ROS Kit. (c) Mean fluorescent intensity was measured at 640/675 nm. (d) The ROS positive ratio (%) is shown as a percentage of the positive cells to the total cell number (, , , and ). (e) Western blot showed the expression level of SOD2, NOX4, and Caspase-3 following IR; GAPDH served as endogenous reference. (f) The densitometric intensities were quantified using Photoshop. All bar graphs were shown as (, , , and ).

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