Effect of kidney-reinforcing and marrow-beneficial traditional Chinese medicine-intervened serum on the proliferation and osteogenic differentiation of bone marrow stromal cells

The present study aimed to investigate the effect of kidney-reinforcing and marrow-beneficial traditional Chinese medicine (TCM)-intervened (KRMBTI)-serum on the proliferation and osteogenic differentiation of bone marrow stromal cells (BMSCs) in rats. Rat BMSCs were isolated and cultured in vitro with various concentrations of serum obtained from rats at different time-points following treatment with low, medium and high doses of KRMBT. The alkaline phosphatase (ALP) activity and proliferation of the BMCSs was assessed to determine the optimal serum sampling time-point and serum concentration. Transforming growth factor (TGF)-β1 expression of the BMSCs was detected using enzyme-linked immunosorbent assay (ELISA), and hepcidin mRNA expression in the rat livers was detected using reverse transcription polymerase chain reaction. The proliferation of BMCSs treated with serum obtained l h after dosing was observed to be significantly higher than that for BMCSs treated with serum obtained at the four other time-points (P<0.05). Furthermore, the proliferation following treatment with 25% KRMBTI-serum was significantly higher than that for the other KRMBTI-serum concentrations (P<0.01). For a 25% concentration of the serum collected at l h, the proliferation in the high- and low-dose KRMBTI-serum groups was significantly higher than that of the medium-dose and control groups (P<0.01) and no statistical significance was observed between the high- and low-dose groups. In the osteogenic differentiation process of the high-dose group, the ALP activity at every time-point was significantly higher than that of the low-dose group and the peak value of the former was achieved at concentrations between 20 and 30%. KRMBTI-serum was shown to promote the expression of TGF-β1. Furthermore, hepcidin was observed to be expressed at significantly higher levels in the high-dose group than in the control group, and hepcidin expression was significantly higher after 10 weeks compared with that after five weeks. These findings suggest that KRMBTI-serum increases TGF-β1 and hepcidin expression levels, which may be the mechanism underlying the promotion of osteogenic differentiation induced by KRMBTI-serum in BMSCs.