Concentration effect of prostaglandin E₂ on the growth factor expression and cell proliferation in bovine endometrial...

Bovine endometrium undergoes various physiological and histological changes that are necessary for blastocyst implantation during oestrous cycle. From pro-oestrus to late-oestrus, endometrium thickens gradually for implantation preparation and exhibits remarkable capacity for self-repair after uterine lining shedding while implantation does not occur. The prostaglandin E₂ (PGE₂ ) secretion pattern is synchronized with endometrial growth during oestrous cycles in bovine endometrium; however, limited information is available regarding the association between PGE₂ secretion and endometrial growth. In this study, the concentration (10^-9 to 10^-5  M) and time effect (2-36 hr) of PGE₂ treatment on a series of growth factors are essential for endometrial growth including connective tissue growth factor (CTGF), fibroblast growth factor-2 (FGF-2), interleukin-8 (IL-8), transforming growth factor-β1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and vascular endothelial growth factor A (VEGFA) mRNA and protein expression, and proliferation of epithelial and fibroblast cells was investigated in bovine endometrial explants in vitro. The results indicated that PGE₂ at concentration about 10^-7 to 10^-5  M could up-regulate CTGF, FGF-2, IL-8, MMP-2, TGF-β1, VEGFA mRNA and protein expression, and could induce the proliferation of epithelial and fibroblast cells and reduce the proapoptotic factor (caspase-3) expression in bovine endometrial explants in vitro. These results collectively improved the possibility of PGE₂ functions in endometrial growth during oestrous cycles.