Effect of Eucommia ulmoides extract on osteoblast proliferation

Purpose: To evaluate the effect of Eucommia ulmoides extract (EUE) on osteoblast proliferation as well as investigate its probable mechanisms of action.Methods: EUE was pharmacologically evaluated at three doses. Osteoblast cells were divided as follows: Group I: negative control; groups II–IV: received EUE (180, 360 and 540 μg/ml, respectively). We performed 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay to determine osteoblast viability following treatment. Alkaline phosphatase (ALP), osteocalcin, and collagen I levels in osteoblasts were quantified using commercially available kits. Thereafter, mRNA and protein expression of ALP, collagen I, osteocalcin, transforming growth factor-β1 (TGF-β1) were measured using real-time quantitative PCR (qPCR) and western blot, respectively.Results: EUE significantly (p < 0.01) promoted osteoblast proliferation at three treatment doses (180, 360, and 540 μg/mL). Furthermore, ALP, osteocalcin, collagen I and TGF-β1 expression at both mRNA and protein levels increased significantly (all p < 0.05) following EUE treatment.Conclusion: The results suggest that EUE may promote osteoblast cell proliferation and that ALP, osteocalcin, collagen I and TGF-β1 gene expression may be involved in the mechanism of action.Keywords: qPCR, collagen I, Bone, Liver, Eucommia ulmoides extract