Osteogenic activity of resveratrol in human fetal osteoblast cells

Background: Resveratrol (RSV) is a polyphenolic phytomolecule naturally present in the skin of grapes fruit. It is reported to be phytoestrogen because of its estrogenic potentials, hence it can be explored to the treatment of osteoporosis. There was no conclusive evidence for the estrogenic potential of RSV in osteoporosis. In this study, RSV is evaluated for its effects on human osteoblast cells. Objective: The main objective of the study was to evaluate RSV on the proliferation and differentiation of immortalized human fetal osteoblastic cells 1.19 (hFOB). Materials and Methods: The osteoblastic cell proliferation and differentiation potentials of RSV were tested by cell viability assay, alkaline phosphatase (ALP) activity, total protein content, and alizarin staining for the mineralization assays. Results: The cell viability assay indicated that RSV was found to be safe at a wider concentration range and the EC50 was 72.05 μM. The therapeutic concentrations as 500 nM and 1 μM were selected for the further assays. RSV at 500-nM and 1-μM concentrations treatment on immortalized human fetal osteoblastic cells 1.19 (hFOB) did not show a significant effect on ALP activity. The total cellular proteins in hFOB increased in a dose-dependent manner on RSV treatment (P ≤ 0.05). The significant staining and the color intensity of the calcium crystals by Alizarin staining assay indicate a stimulatory effect on the mineralization phase of bone formation. Conclusion: In mature osteoblasts, ALP activity is expressed in early stage, whereas mineralized nodules are formed in the late stage of differentiation. Therefore, the present study suggests that RSV stimulates the process of bone formation through activation of late differentiation phase and may have positive effects on osteoblastic differentiation potential.