Cyclophilin B enhances the proliferation and differentiation of MC3T3-E1 cells via JAK2/STAT3 signaling pathway

Abstract

The aim of this study was to investigate the effects of cyclophilin B on MC3T3-E1 cells and the underlying mechanism. CCK-8 assay was used to evaluate the cell activity, polymerase chain reaction to verify the overexpression of cyclophilin B, western blot to detect the protein levels, and clone formation assay to evaluate the proliferation ability. Alkaline phosphatase (ALP) activity was assessed by ALP assessment kit. The results showed that compared with the control group/negative control (NC) group, the cells in the cyclophilin B overexpression group possessed enhanced proliferation ability, higher ALP activity and enhanced mineralization. Compared with the control group, the levels of Oct4, Sox2, Runx2, collagen I, BMP2 and BMPR-II, as differentiation-related proteins, were increased by cyclophilin B. Compared to the NC group, the expression levels of p-JAK2 and p-STAT3 in the cyclophilin B overexpression group were higher, suggesting that cyclophilin B can activate the JAK2/STAT3 signaling pathway. The expression levels of p-JAK2 and p-STAT3 in the cyclophilin B overexpression group were higher than that in the cyclophilin B overexpression + JAK2 inhibitor group, further confirming the hypothesis that the JAK2/STAT3 signaling pathway was activated by cyclophilin B. Taken together, the results suggest that cyclophilin B promotes the proliferation and differentiation of MC3T3-E1 cells via the JAK2/STAT3 signaling pathway and may be a promising therapeutic target for bone injury.