A traditional Chinese medicine formula extracts stimulate proliferation and inhibit mineralization of human mesenchymal stem cells in vitro

Aim of the studyTo investigate the effects of a traditional Chinese medicine (TCM) formula extract, named as ZD-I, on the proliferation and osteogenic differentiation of human mesenchymal stem cells (hMSCs) in vitro.Materials and methodsWhen hMSCs cultivated in the basal medium with ZD-I, cell viability was assessed by MTT assay and cellular proliferation was assessed by SYBR green I assay. The effects of ZD-I on osteogenic differentiation of hMSCs were assessed by alkaline phosphatase (ALP) activity, mineralization assay and real-time RT-PCR.ResultsZD-I (0.78–100 μg/ml) was non-cytotoxic. The 50% inhibitory concentration (IC50) of hMSCs was 200 μg/ml. ZD-I (0.78–50 μg/ml) stimulated the proliferation of hMSCs. ZD-I did not change ALP activity of hMSCs cultivated in osteogenic medium in the early stage (4 and 7 days), but ZD-I inhibited the mineralization of hMSCs through down-regulation of several osteogenic markers (e.g. osteocalcin, bone morphogenetic protein 2 and osteopontin) in the late stage.ConclusionsZD-I stimulate cellular proliferation and decrease the bone mineral deposition of hMSCs. These results suggest ZD-I may play an important therapeutic role in osteoarthritic patients by improving proliferative capacity of hMSCs and inhibiting the mineralization of hMSCs.