Expression of aromatase and estrogen-related receptors in human bone marrow mesenchymal stem cells / 中国组织工程研究

ABSTRACT

BACKGROUND:Estrogen signaling pathway for interaction between aromatase and estrogen-related receptor may exist in bone marrow mesenchymal stem cel s, which is used for regulating biological activity of bone marrow mesenchymal stem cel s. OBJECTIVE:To observe the expression of aromatase and estrogen-related receptors in adult bone marrow mesenchymal stem cel s during osteogenic differentiation. METHODS:Bone marrow mesenchymal stem cel s were respectively cultured in low-glucose DMEM medium (control group) and osteogenic induction medium (induction group). Cel proliferation and calcium deposition were determined by MTT assay and alizarin red staining, respectively. The expression of aromatase, estrogen receptorα, estrogen receptorβ, and estrogen-related receptorαduring osteogenic differentiation were determined by real-time PCR and western blot analysis. Estradiol levels in supernatants and lysates were detected by ELISA method. RESULTS AND CONCLUSION:In the induction group, the proliferation ability of bone marrow mesenchymal stem cel s was the strongest at 72 hours of culture;while there were a great amount of calcium nodules formed at 21 days of culture. Results from PCR and western blot assay showed that the expression of aromatase and estrogen receptorαwas improved in the induction group, but the expression of estrogen-related receptorαwas inhibited. There was no difference in the expression of estrogen receptorβbetween the two groups. ELISA results indicated that the level of estradiol in the supernatant of induction group was the highest. These findings indicate that aromatase, estrogen receptorα, estrogen receptorβand estrogen-related receptorαare al involved in osteogenesis of bone marrow mesenchymal stem cel s. Moreover, estradiol can be synthesized and secreted in bone marrow mesenchymal stem cel s, and most likely, promote the osteogenic differentiation of bone marrow mesenchymal stem cel s by related receptor pathway.