Wingless ligands and beta‐catenin expression in the rat endometrium: The role of Wnt3 and Wnt7a/beta‐catenin pathway at the embryo–uterine interface

Abstract

Wnt/beta-catenin signaling may play an essential role in endometrial decidualization, placentation, and the establishment of pregnancy. We investigate here the possible roles, immunolocalizations, and synthesis of the Wnt3, Wnt7a, and betacatenin proteins in the rat endometrium during the estrous cycle and early postimplantation period. Wnt3 and Wnt7a had a similar localization and dynamic expression relative to the endometrial stages. Wnt7a immunostaining was not limited only to the luminal epithelial cells, but also to strong stainings in the stromal and endothelial cells. Wnt3, Wnt7a, and beta-catenin were highly synthesized and colocalized at the trophoblast-decidual interface; and were more obvious in the primary decidual zone, the GTCs, and the ectoplacental cone. Beta-catenin was strongly localized at the borders of the mature decidual cells; however, Wnt3 and Wnt7a immunolocalizations were decreased in those cells. As such, the immunolocalization of Wnt3, Wnt7a, and beta-catenin shifted with decidualization and placentation. The expression level of Wnt3, Wnt7a, and beta-catenin messenger RNAs increased in early pregnancy, and especially between Days 8.5 and 9.5. The dramatic changes in the expression of Wnt3, Wnt7a, and beta-catenin observed during the early days of pregnancy and the estrous cycle may indicate their roles in decidualization, stromal cell proliferation, and trophoblast invasion.

WNT3 Hypopethylation Counteracts low Activity of the Wnt Signaling Pathway in the Placenta of Preeclampsia

“…WNT3 also plays an important role in embryonic development and regulates trophectoderm differentiation in blastocysts [35]. Kaloglu C et al found that WNT3 is involved in regulating decidualization, stromal cell proliferation and trophoblast cell in ltration in the rat uterus [36]. In the present study, we found that the promoter region of WNT3 was hypomethylated and that its expression was increased in preeclamptic placentas.…”

WNT3 hypomethylation counteracts low activity of the Wnt signaling pathway in the placenta of preeclampsia

“…WNT3 also plays an important role in embryonic development and regulates trophectoderm differentiation in blastocysts [ 35 ]. Kaloglu C et al found that WNT3 is involved in regulating decidualization, stromal cell proliferation, and trophoblast cell infiltration in the rat uterus [ 36 ]. In the present study, we found that the promoter region of WNT3 was hypomethylated and that its expression was increased in preeclamptic placentas.…”

Genome-wide association studies for economically important traits in mink using copy number variation

“…In the current study, several WNT family genes were identified to be associated with reproduction traits in American mink, including WNT3 and WNT9B (both found within the duplication CNVR118), and WNT3A (overlapped with the deletion CNVR23). It is well-documented that the expression of WNT3 during the early pregnancy mediates the stromal cell proliferation and trophoblast invasion, eventually affecting the embryonic development 86 . Comparably, the WNT9B gene has been reported as one of the key genes associated with inducing the gonadotropin-releasing hormone secretion during follicular development in sheep 87 .…”