Experimental study of osteogenic differentiation of precartilaginous stem cells induced by calcitonin gene-re-lated peptide / 中华物理医学与康复杂志

ABSTRACT

Objective To investigate the effect of calcitonin gene-related peptide ( CGRP ) in inducing os-teogenic differentiation of rat precartilaginous stem cells in vitro and the underlying mechanisms. Methods Rat pre-cartilaginous stem cells ( PSCs) were cultured in complete osteogenesis medium containing DMEM/F-12 medium and different concentrations (0, 10-8,10-9,10-10mol/L) of CGRP, the morphology changes of PSCs were observed. The proliferation of PSCs was examined at different time points by CCK-8. All the PSCs were then randomly assigned to an experimental group and a control group. The PSCs in the experimental group were cultured in complete osteogenesis medium with 10-10 mol/L CGRP , while the control group cultured merely in complete osteogenesis medium was re-ceived no special intervention. Both groups were stained by Alizarin Red and the expression of alkaline phosphatase (ALP) was detected. The osteogenic genes (RUNX2,OPN and BGP) were measured by use of RT-PCR. The activa-tion of Wnt/β-catenin signaling pathway was tested by using Western blotting to evaluate the effect of CGRP . Results Compared to the control group ( the concentration of CGRP was 0 mol/L) , the concentration of ALP was significantly higher in the experimental group, calcium deposition was significantly more obvious, and the expression of the osteogenic genes such as RUNX2,OPN and BGP as well as theβ-catenin protein expression were up-regulated significantly. However, CGRP had no effect on cell proliferation. Conclusion CGRP activated Wnt/β-catenin sig-nal pathway and induced osteogenic differentiation of precartilaginous stem cells.