The effect of female sex steroid hormones on osteogenic differentiation of endometrial stem cells.

Bone regeneration is a significant and crucial health issue worldwide. Tissue bioengineering has shown itself to be the best substitute for common clinical treatment of bone loss. The suitable cell source is human endometrial stem cells (hEnSCs) which have several suitable characteristics for this approach. Since sex steroid hormones are involved in expansion and conservation of the skeleton, the effect of two sex steroid hormones known as estrogen (17-beta estradiol) and progesterone on osteogenic differentiation of hEnSCs were examined. For this purpose, hEnSCs were treated with 17-beta estradiol and progesterone separately (1 x 10(-6) M) and simultaneously (1 x 10(-7) M). Osteogenic differentiation tests including measurement of total mineral calcium content, Alizarin Red staining, the quantitative expression levels of some osteogenic markers by Real-time RT-PCR, and immunofluorescence staining were performed at 7 and 14 days of differentiation. To exhibit the morphology of the cells in osteogenic and culture medium, the hEnSCs were stained with Acridine Orange (AO) solution. In this research, MTT assay and AO staining revealed progesterone and 17-beta estradiol increase the proliferation of hEnSCs in a dose-dependent manner. Furthermore, the results of calcium content analysis, Real-time RT-PCR assay, and all tests of differentiation staining have shown that 17-beta estradiol and progesterone cannot induce hEnSCs' osteogenic differentiation. In conclusion, it is indicated that 17-beta estradiol and progesterone do not have positive effects on hEnSCs' osteogenic differentiation in vitro.