Reproductive stage and sex steroid hormone levels influence the expression of mesenchymal stromal cell (MSC) markers in the equine endometrium

Abstract

Mesenchymal stem or stromal cells (MSCs) play key roles in tissue homeostasis. In the cyclic equine endometrium, this may be regulated by changes in serum concentrations of sex steroid hormones. This study was designed to investigate the changes in endometrial expression of MSC markers during reproductive cycles in mares and the influence of sex steroid hormones on endometrial MSC proliferation in vitro. Endometrial biopsies were collected from pony mares at different reproductive stages (estrus; day 5 and 13 after ovulation; seasonal anestrus; 20 h and 7days post-partum; n = 5 per stage) and were analyzed by RT-qPCR. MSC (CD29, CD44, CD73, CD90, CD105) and perivascular (CD146, NG2) markers were present in all samples irrespective of reproductive stage. Transcript levels of most markers were present at lowest levels on day 5 after ovulation and at 20 h post-partum. MSCs isolated from endometrial tissue (n = 6 mares) were cultured in the presence of progesterone (0.01-100 μM) and estradiol 17β (0.1-1 μM), and cell proliferation was analyzed using alamarBlue assay. Relative to cells incubated in steroid-depleted media, both progesterone and estradiol 17β moderately increased cell proliferation (1.1- and 1.2-fold, respectively) independently of the concentration used. In conclusion, our results suggest that levels of MSC markers in equine endometrium dynamically change across reproductive cycles and that MSC populations are in part regulated by sex steroids.

Bone marrow mesenchymal stem cells derived from juvenile macaques reversed ovarian ageing in elderly macaques

“…These results are consistent with previous studies reporting the ability of MSCs to restore ovarian structure and sex hormone secretion [ 22 , 27 , 28 ]. Furthermore, previous studies have demonstrated that the number of MSCs in different cell cycle stages can be adjusted by adjusting the concentrations of sex hormones [ 29 , 30 ], suggesting that after BMMSCs restore the secretion of sex hormones, sex hormones may in turn regulate the biological function of MSCs.…”