The effect of neuropeptides on proliferation of rat bone marrow mesenchymal stem cells

Abstract

Objective To investigate the effects and mechanism of calcitonin gene-related peptide (CGRP) and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells. Methods The rBMSCs were isolated using whole bone marrow adherence method. In the different periods of culturing (1, 2,and 3 weeks), expressions of the neuropeptide receptors were detected by Western Blot and reserve transcriptase-polymerase chain reaction (RT-PCR). The BMSCs were treated with CGRP and SP at concentration 10-8 mol/L at different time (1,3,5,7,9 days), cell proliferation was detected with MTT assay, the protein expressions of cyclin D1 ,cyclin E and p53 were examined using Western Blot. Results The CGRP receptor and SP receptor were expressed in BMSCs. The expression of CGRP receptor was statistically higher than that of SP receptorat the same time point. The growth curves of BMSCs cultured by both neuropeptides had similar appearance. CGRP and SP stimulated the proliferation of BMSCs significantly at 9 days and 7 and 9 days. In this process, the expressions of cyclinDl and cyclinE were up-regulated by CGRP, SP only enhanced the expression of cyclinE; these effects all reached a peak at 5 days. The expression of p53 was down-regulated by both neuropeptides. Conclusion CGRP and SP had direct effects on the proliferation of BMSCs, the regulation of cell cycle proteins is one of the mechanisms. Key words: Calcitonin gene-related peptide; Substance P; Myeloid progenitor cells; Cell cycle