Abstract：Mesenchymal stem cells (MSCs) are multipotent stem cells derived from the mesoderm, which have ability to differentiate into osteoblasts, chondrocytes and adipocytes. In this experiment, the effects of cyclopamine (CPA), a specific inhibitor of hedgehog signaling pathway, on cell division cycle and adipogenic induction and osteogenic induction of bovine(Bos taurus) adipose mesenchymal stem cells (AMSCs) were studied. After isolation and identification of AMSCs, CPA was used to treat AMSCs, then effects of CPA on cell cycle and adipocyte differentiation and osteoblast differentiation associated gene expressions were investigated using flow cytometry and Real-time PCR. The results indicated that treatment of AMSCs with CPA at different concentrations affected cell cycle progression in a dose-dependent manner. CPA resulted in cells arrested at G0/G1 stages. After adipogenic induction and osteogenic induction, no obvious morphological differences was observed in the formation of adipocytes and osteoblasts. However, the Real-time PCR detections of the induced cells showed that both peroxisome proliferator-activated receptorγ(PPARγ, critical adipogenic gene) and runt-related transcription factor 2(Runx, critical osteogenic gene) were significantly changed during adipogenic induction or osteogenic induction. PPARγ expression was significantly increased after 4 d treatment compared to the control (P＜0.01), Runx expression was lower in treatment group than the control (P＜0.01). These results suggested CPA induced AMSCs arrested at G0/G1 stages and CPA treatments of AMSCs affected adipogenic and osteogenic induction in gene expression level. This experiment provides a basis for the study of hedgehog signaling pathway in AMSCs proliferation and differentiation.
