The Separation of Antler Polypeptide and Its Effects on the Proliferation and Osteogenetic Differentiation of Bone Marrow Mesenchymal Stem Cells

BACKGROUND: Colla Cornus Cervi (CCC) has been used as a traditional Chinese medicine in the treatment of osteoporosis and osteonecrosis of the femoral head. However, the bioavailability of CCC is seriously limited owing to its large molecular weight and complex ingredients. In the present study, antler polypeptide was separated from CCC, and the effects of antler polypeptide on rat bone marrow mesenchymal stem cells (BMSCs) were investigated. METHODS: Antler polypeptide was separated from Colla Cornus Cervi by ultrafiltration into different samples according to the molecular weight. The total peptide content of these samples was determined by the biuret method. The content of antler polypeptide in different samples was quantified by high-performance liquid chromatography (HPLC). The effects of antler polypeptide at different concentrations on the proliferation, cell cycle, alkaline phosphatase activity, and BMP7 expression of BMSCs were investigated. RESULTS: Antler polypeptide was separated by ultrafiltration into different samples: A (molecular weight <800 Da), B (molecular weight 800–1500 Da), and C (molecular weight >1500 Da). The total peptide contents of A, B, and C were 0.602 mg/mL, 8.976 mg/mL, and 38.88 mg/mL. Antler polypeptide B eluted at 14.279∼15.351 min showed that the content of antler polypeptide was significantly higher than that of A and C with a peak area of 933.80927. The BMSCs proliferation rate (84.66%) of polypeptide B was the highest at the concentration of 1.578 × 10(−2) g/mL. Antler polypeptide B significantly promoted the proliferation of BMSCs with a proliferation index of 38.68%, which was significantly higher than that of the other groups. Antler polypeptide B significantly enhanced the activity of alkaline phosphatase in BMSCs compared to that of the blank group (P < 0.001). Antler polypeptide B increased the BMP7 protein expression in BMSCs. CONCLUSIONS: Results suggested that antler polypeptide may promote the proliferation and osteogenic differentiation of BMSCs. Our study lays an experimental foundation for the further development and application of antler polypeptide in medicine.