Effect of hyperoxia on cysteinyl aspartate specific proteinase-3 and proliferating cell nuclear antigen expressions in bone mesenchymal stem cells

Abstract

Objective To investigate the effect of hyperoxia on the expressions of cysteinyl aspartate specific proteinase-3(Caspase-3) and proliferating cell nuclear antigen (PCNA) in bone marrow mesenchymal stem cells(BMSCs). Methods Primary BMSCs from SD rats were cultured in vitro, BMSCs grew to 70%-80% degrees of fusion and then were randomly divided into room air group and hyperoxia exposure group.Each group was divided into 5 sub-groups, and cultured for 0, 3, 6, 12, and 24 h respectively.Morphology investigation with inverted phase contrast microscope was adopted.The expressions of Caspase-3 and PCNA protein levels were detected by Western blot. Results (1)As time wenty by, compared with room air group, the gap between cells increased, some of the cells became circular, and cell detachment and floating appeared in the hyperoxia-exposure group (>12 h) compared with room air group.(2)As time went on, compared with the room air group, the expression levels of Caspase-3 protein in the hyperoxia-exposure group were increased, and the difference was significant after 6 hours of culture (0.27±0.04 vs 0.14±0.02, t=5.03, P=0.007). (3)Compared with room air group, the PCNA levels of the hyperoxiaexposure group(6 h) decreased, and the difference in PCNA protein expression levels was significant after 6 hours of culture (0.27±0.04 vs 0.38±0.04, t=3.37, P=0.028). Conclusions Hyperoxia exposure increases Caspase-3 expression levels and decreases PCNA expression, which may affect the proliferation and apoptosis of BMSCs. Key words: Hyperoxia; Bone mesenchymal stem cell; Proliferating cell nuclear antigen; Cysteinyl aspartate specific proteinase 3