The ubiquitous hyaluronan: Functionally implicated in the oviduct?

Martínez

et al. 2020

Sci Rep

Semen modifies the expression of genes related to immune function along the porcine female internal genital tract. Whether other pathways are induced by the deposition of spermatozoa and/or seminal plasma (SP), is yet undocumented. Here, to determine their relative impact on the uterine and tubal transcriptomes, microarray analyses were performed on the endocervix, endometrium and endosalpinx collected from pre-ovulatory sows 24 h after either mating or artificial insemination (AI) with specific ejaculate fractions containing spermatozoa or sperm-free SP. After enrichment analysis, we found an overrepresentation of genes and pathways associated with sperm transport and binding, oxidative stress and cell-to-cell recognition, such as PI3K-Akt, FoxO signaling, glycosaminoglycan biosynthesis and cAMP-related transcripts, among others. Although semen (either after mating or AI) seemed to have the highest impact along the entire genital tract, our results demonstrate that the SP itself also modifies the transcriptome. The detected modifications of the molecular profiles of the pre/peri-ovulatory endometrium and endosalpinx suggest an interplay for the survival, transport and binding of spermatozoa through, for instance the up-regulation of the Estrogen signaling pathway associated with attachment and release from the oviductal reservoir.

Section: Discussionmentioning

confidence: 99%

The role of semen and seminal plasma in inducing large-scale genomic changes in the female porcine peri-ovulatory tract

Martínez

et al. 2020

Sci Rep

“…The presence of CD44 in the EVs of the sperm‐free seminal plasma play a crucial role in most mammals, considering that prostasomes are recruited by and attached to spermatozoa in response to early capacitation events in the uterus and oviduct, and stimulate secondary pathways related to hypermotility and acrosome reaction, when approaching the oocyte (Aalberts et al, ). In addition, it is known that rooster spermatozoa do not complete maturation in the epididymis (Froman & Kirby, ), thus we hypothesized about a role for CD44 in this process, as documented in mammals (Rodriguez‐Martinez et al, ). However, no CD44 binding by Western blotting was found in any of the SF samples from the three chicken breeds studied.…”

Section: Discussionmentioning

confidence: 92%

Chicken seminal fluid lacks CD9‐ and CD44‐bearing extracellular vesicles

Ntzouni

Reprod Domestic Animals

et al. 2020

The avian seminal fluid (SF) is a protein‐rich fluid, derived from the testis, the rudimentary epididymis and, finally, from the cloacal gland. The SF interacts with spermatozoa and the inner cell lining of the female genital tract, to modulate sperm functions and female immune responsiveness. Its complex proteome might either be free or linked to extracellular vesicles (EVs) as it is the case in mammals, where EVs depict the tetraspanin CD9; and where those EVs derived from the epididymis (epididymosomes) also present the receptor CD44. In the present study, sperm‐free SF from Red Jungle Fowl, White Leghorn and an advanced intercross (AIL, 12th generation) were studied using flow cytometry of the membrane marker tetraspanin CD9, Western blotting of the membrane receptor CD44 and electron microscopy in non‐enriched (whole SF) or enriched fractions obtained by precipitation using a commercial kit (Total Exosome Precipitation Solution). Neither CD9‐ nor CD44 could be detected, and the ultrastructure confirmed the relative absence of EVs, raising the possibility that avian SF interacts differently with the female genitalia as compared to the seminal plasma of mammals.

“…In vitro selection of spermatozoa to improve IVF is unlikely to correspond to events occurring in vivo [19]. Under in vivo conditions, progressively motile spermatozoa are selected during their journey through the genital tract [26,27] and most SP is removed from the sperm surface by interaction with the female (washing with intraluminal fluid, etc.) before arrival to the site of fertilization.…”

Section: Introductionmentioning

confidence: 99%

Does the Pre-Ovulatory Pig Oviduct Rule Sperm Capacitation In Vivo Mediating Transcriptomics of Catsper Channels?

Martínez

et al. 2020

IJMS

Spermatozoa need to conduct a series of biochemical changes termed capacitation in order to fertilize. In vivo, capacitation is sequentially achieved during sperm transport and interaction with the female genital tract, by mechanisms yet undisclosed in detail. However, when boar spermatozoa are stored in the tubal reservoir pre-ovulation, most appear to be in a non-capacitated state. This study aimed at deciphering the transcriptomics of capacitation-related genes in the pig pre-ovulatory oviduct, following the entry of semen or of sperm-free seminal plasma (SP). Ex-vivo samples of the utero-tubal junction (UTJ) and isthmus were examined with a microarray chip (GeneChip ® Porcine Gene 1.0 ST Array, Thermo Fisher Scientific) followed by bioinformatics for enriched analysis of functional categories (GO terms) and restrictive statistics. The results confirmed that entry of semen or of relative amounts of sperm-free SP modifies gene expression of these segments, pre-ovulation. It further shows that enriched genes are differentially associated with pathways relating to sperm motility, acrosome reaction, single fertilization, and the regulation of signal transduction GO terms. In particular, the pre-ovulation oviduct stimulates the Catsper channels for sperm Ca 2+ influx, with AKAPs, CATSPERs, and CABYR genes being positive regulators while PKIs and CRISP1 genes appear to be inhibitors of the process. We postulate that the stimulation of PKIs and CRISP1 genes in the pre-ovulation sperm reservoir/adjacent isthmus, mediated by SP, act to prevent premature massive capacitation prior to ovulation.