Although physiologic amount of inflammation is necessary for successful implantation, pathological inflammation inhibits the expression of receptivity molecules and genes. Because hydrosalpinges is an inflammatory disease, adverse effects of hydrosalpinges on implantation may be in part mediated by disturbed endometrial expression of nuclear factor-kappa B (NF-κB), a dimer implicated in inflammation. We examined the expression of NF-κB p65 (Rel A) during the window of implantation in the endometrium of infertile women (n = 14) with uni or bilateral hydrosalpinges prior to and following salpingectomy and of fertile controls (n = 14) by immunohistochemistry. We assessed the influence of salpingectomy on NF-κB p65 expression by comparing pre- and post-operative endometrial samples. To evaluate the intensity of endometrial NF-κB p65 (Rel A) immunoreactivity, H-score method was used. We showed a decrease in NF-κB p65 expression in 13 out of the 14 post-salpingectomy endometrial samples. The mean NF-κB p65 level was significantly higher in the endometrium of women with hydrosalpinges before salpingectomy compared with control cases without hydrosalpinges (3.94 ± 6.2 vs 2.18 ± 0.7, p < .02). Salpingectomy decreased the mean endometrial NF-κB p65 levels in both unilateral and bilateral hydrosalpinges (2.87 ± 1.1). When we compared the endometrial NF-κB p65 levels of the post-salpingectomy samples with their age-matched fertile controls, we did not observe any significant difference. After salpingectomy, the mean H-score of endometrial NF-κB p65 expression significantly decreased to a level similar to that of the fertile group (2.87 ± 1.1 vs 2.18 ± 0.7, p > .64). NF-κB p65 expression was detected in cytoplasmic and membranous parts of luminal and glandular epithelial cells of endometrium obtained before salpingectomy. Both epithelial and stromal components of the endometrium showed decreased staining for NF-κB p65 compared with the pre- and post-salpingectomy samples. The decreased NF-κB p65 (Rel A) immunoreactivity was predominantly localized to luminal and glandular epithelial cells. Uni or bilateral hydrosalpinges causes pathological endometrial inflammation. Improvement in pathological inflammation following salpingectomy in women with hydrosalpinges may be in part mediated by the downregulation of endometrial NF-κB p65 (Rel A) expression.
Keywords: Endometrium; Hydrosalpinx; Nuclear factor kappa beta; Receptivity; Salpingectomy.