Effect of seminal plasma or transforming growth factor on bovine endometrial cells

Abstract

Semen induces post-coital inflammation of the endometrium in several species. Post-coital inflammation is proposed to alter the endometrial environment of early pregnancy, mediate embryonic development and modulate the maternal immune response to pregnancy. In cattle, it is common for pregnancies to occur in the absence of whole semen due to the high utilization of artificial insemination. Here, we have utilized a cell culture system to characterize semen-induced expression of inflammatory mediators in bovine endometrial cells and test the efficacy of transforming growth factor beta as the active agent in mediating any such change. We hypothesize that seminal plasma-derived transforming growth factor beta increases the expression of inflammatory mediators in bovine endometrial cells. Initially, we describe a heat-labile cytotoxic effect of seminal plasma on BEND cells, and a moderate increase in IL1B and IL6 expression. In addition, we show that transforming growth factor beta is present in bovine semen and can increase the expression of endometrial IL6, whereas blocking transforming growth factor beta in semen ameliorates this effect. However, intra-uterine infusion of seminal plasma, sperm or transforming growth factor beta did not alter the endometrial expression of inflammatory mediators. We conclude that bovine semen can modulate endometrial gene expression in vitro, which is partially due to the presence of transforming growth factor beta. It is likely that additional, unidentified, bioactive molecules in semen can alter the endometrial environment. Characterizing bioactive molecules in bovine semen may lead to the development of additives to improve artificial insemination in domestic species.

Extracellular vesicles from seminal plasma improved development of in vitro-fertilized mouse embryos

“…Transforming growth factor-β in seminal plasma induced inflammatory cytokinesis in the mother's endometrium or cervix, resulting in the recruitment of inflammatory immune cells after insemination (Rizo et al, 2019). Toll-like receptor (TLR)-4 signalling mediated by seminal plasma plays an important role in the induction of inflammatory cytokine expression and the expansion of the cumulus cell complex (Bromfield and Sheldon, 2011;Schjenken et al, 2015).…”

Bovine endometrial cells do not mount an inflammatory response to Leptospira

“…Viability of BEND cells was assessed by the cellular reduction of MTT (Thermo Fisher Scientific) as previously described ( Rizo et al 2019 ). Briefly, BEND cells were cultured in 96-well culture plates (TPP) at a density of 10 5 cells/mL in 200 μL and equilibrated for 24 h at 38.5°C in a humidified atmosphere containing 95% air and 5% CO 2 .…”

“…Uterine samples from cows in cohorts 1 and 2 were collected using the cytobrush technique immediately after initial urine collection as previously described ( Rizo et al 2019 ). Briefly, external genitalia were cleaned using 70% ethanol, and the cytobrush tool (Medscan Medical, Cooper Surgical, Trumball, CT) contained inside a metal sheath and covered by a sanitary chemise (WTA, Cravinhos, Brazil) was introduced into the vagina.…”

Effect of seminal plasma treatment on conception rate in Holstein cows

“…Additionally, inflammation due to seminal fluid in the endometrium leads to the production of embryokines, which play a role in regulating embryonic growth and development. It is moreover indicated to aid in maternal recognition of the embryo through regulation of the maternal immune response (Mateo-Otero et al, 2020;Rizo et al, 2019;Vera et al, 2003).…”