Estradiol Reduces Connexin43 Gap Junctions in the Uterus during Adenomyosis in Cows

Abstract

Adenomyosis is defined as the presence of glandular foci external to the endometrium of the uterus, either in the myometrium or/and perimetrium, depending on the progress of this dysfunction. To date, we showed that steroids secretion and prolactin expression and proliferative processes are disturbed during uterine adenomyosis in cows. During endometriosis in eutopic endometrium in women, gap junctions are down regulated. The transmembrane gap junction protein, connexin (Cx43) is necessary for endometrial morphological, biochemical and angiogenic functions. The aim of this study is recognition of adenomyosis etiology by determination of the role of Cx43 in this process. Immunolocalization and comparison of Cx43 mRNA and protein expression in healthy (N=9) and adenomyotic uterine tissue (N=9), and Cx43 mRNA expression (real time PCR) in uterine stromal -myometrium co-culture under 24-hour stimulation with 17-beta estradiol (10 -7 M) isolated from healthy (N=5) and adenomyotic (N=5) cows were determined. Cx43 was localized in healthy and adenomyotic uteri. mRNA and protein expression was down-regulated in uterine tissue in adenomyotic compared with healthy cows (p<0.05). Estradiol stimulated Cx43 mRNA expression in myometrial cell culture and co-culture of stromal and myometrial cells in adenomyotic compared with healthy cows (p<0.05). In summary, down-regulation of Cx43 expression in the junction zone might play an important role in pathogenesis of adenomyosis. Estradiol modulates gap junctions during adenomyosis.

Effect of ovarian steroids on vascular endothelial growth factor a expression in bovine uterine endothelial cells during adenomyosis

“…The primer sequences for determining the mRNA relative abundance of VEGFA, VEGFR1, and VEGFR2 genes were designed using Primer Express Software 3 (Applied Biosystems). The housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), was chosen based on previous results that confirmed its stable expression in uterine tissue [48], and two other reference genes: beta actin (ACTB) and 18S ribosomal RNA (RN18S). The primer sequences, GenBank accession numbers, genes and expected product size are detailed in Table 2.…”