Proteome of the periovulatory oviduct and uterus of goats as related to nutritional balance

Oral exposure to bisphenol S is associated with alterations in the oviduct proteome of an ovine model, with aggravated effects in overfed females

BACKGROUND

Bisphenol S (BPS) is a substitute for bisphenol A in plastic manufacturing and, as a potential endocrine disruptor, may alter the physiology of the oviduct, in which fertilization and early embryo development take place in mammals. The objective of this study was to assess the effect of a daily dietary exposure to BPS combined with a contrasted diet on the oviduct fluid proteome using an ovine model.

RESULTS

Eighty adult cyclic ewes were allotted to four groups (20/group): overfed (OF) consuming 50 µg/kg/day of BPS in their diet, underfed (UF) consuming 50 µg/kg/day of BPS, and non-exposed controls in each diet group. After three months, the mean body condition score, plasma levels of glucose and non-esterified fatty acids were significantly higher in OF than in UF females. The proteins in collected OF samples (50 µg) were analyzed by nanoliquid chromatography coupled with tandem mass spectrometry (nanoLC-MS/MS). Overall, 1563 proteins were identified, among which 848 were quantified. Principal component analysis of the data revealed a clear discrimination of samples according to the diet and a segregation between BPS-exposed and non-exposed females in overfed ewes. Hierarchical clustering of differentially abundant proteins (DAPs) identified two clusters of 101 and 78 DAPs according to the diet. Pairwise comparisons between groups revealed a stronger effect of BPS in OF than in UF females (70 vs. 24 DAPs) and a stronger effect of the diet in BPS-exposed than non-exposed females (56 vs. 36 DAPs). Functional analysis of DAPs showed an enrichment in metabolic processes, immune system, cell response to stress, and reproductive processes.

CONCLUSIONS

This work highlights for the first time the important impact of BPS on the oviduct proteome, with larger effects seen in OF than UF females. These results, together with previous ones, raise health concerns for everyone and call for a greater regulation of BPS in the food industry.

Use of monosodium-glutamate as a novel dietary supplement strategy for ovarian stimulation in goats

This study aimed to investigate the reproductive effects of adding monosodium glutamate (MSG) to the diet of goats. Eleven adult goats received synchronized estrus and follicular waves using three prostaglandin analog injections every seven days. Goats allocated to individual pens received 1 g/kg BW of MSG in their diet for 23 days (MOGLU group, n = 6), whereas the control group (n = 5) maintained the base diet. The supplemented animals showed an increase in dry matter intake (P < 0.0001) and a reduction in heart rate (P < 0.05), respiratory rate, and ruminal movement (P < 0.001). Surface and rectal temperatures were higher in the MOGLU group, (P < 0.0001) with a significant increase in the afternoon. There was an increase (P < 0.05) in the frequency of behaviors related to rumination, defecation, and urination in the MOGLU group, and a reduction in behaviors associated with stress (P < 0.05). No differences were observed in the plasma levels of proteins, albumin, urea, cholesterol, or triglycerides. Glucose levels were lower (P < 0.05) in the MOGLU group, which also showed increased glutathione peroxide levels during the induction of ovulation. Supplemented animals recorded a larger number (P < 0.05) of follicles throughout the experimental period and higher intraovarian blood perfusion (P < 0.05) during ovulation induction. We conclude that MSG exerts a positive effect on the reproductive response in goats and therefore represents an effective nutritional supplement.

A Comparative Proteomic Analysis to Explore the Influencing Factors on Endometritis Using LC-MS/MS

The inflammatory system activated by uterine infection is associated with decreased fertility. Diseases can be detected in advance by identifying biomarkers of several uterine diseases. Escherichia coli is one of the most frequent bacteria that is involved in pathogenic processes in dairy goats. The purpose of this study was to investigate the effect of endotoxin on protein expression in goat endometrial epithelial cells. In this study, the LC-MS/MS approach was employed to investigate the proteome profile of goat endometrial epithelial cells. A total of 1180 proteins were identified in the goat Endometrial Epithelial Cells and LPS-treated goat Endometrial Epithelial Cell groups, of which, 313 differentially expressed proteins were accurately screened. The proteomic results were independently verified by WB, TEM and IF techniques, and the same conclusion was obtained. To conclude, this model is suitable for the further study of infertility caused by endometrial damage caused by endotoxin. These findings may provide useful information for the prevention and treatment of endometritis.

Proteomic analysis of uterine lavage fluid of dairy cows at different time after delivery by mass spectrometry

Endometritis is a common disease in the reproductive system, which is the infection and inflammation of the endometrium. In severe cases, it can affect the myometrium and adversely affect the subsequent fertility of dairy cows. We used a mass spectrometry-based technique to compare proteomics of uterine lavage fluid between healthy cows and cows with cytological endometritis classified according to 100-day postpartum pregnancy results and diagnosis result. The uterine lavage fluid of dairy cows collected at 15 and 30 days after delivery was analyzed. 15 days postpartum, we identified a total of 1129 proteins in the control and cytological endometritis (CEM) groups. Among them, 160 proteins were accurately screened out. 30 days postpartum, we identified a total of 846 proteins in the control and cytological endometritis (CEM) groups. Among them, 186 proteins were accurately cytological endometritis (CEM). Endometritis is a costly reproductive disease in lactating cows, which needs to be diagnosed in time. Using proteomics method based on gel mass spectrometry, we compared the proteome of uterine lavage fluid of dairy cows with and without cytological endometritis to characterize the changes of proteomic characteristics associated with postpartum uterine disease. To provide reference for clinical application and basic research.

Proteomic Differences Between the Ovulatory and Anovulatory Sides of the Mare's Follicular and Oviduct Fluid

The follicular fluid and oviduct fluid play major roles in oocyte maturation, sperm activation, and fertilization. To better understand the physiological environments for equine oocyte maturation and fertilization, here we conducted the proteome analysis and comparison on follicular fluids and oviduct fluids from the ovulatory side and the anovulatory side. The results showed that there is no significant difference between two side oviduct fluids, but a total of 71 differential abundance proteins (DAPs) were identified between two side follicular fluids, of which 9 are up-regulated and 62 are down-regulated in ovulatory side follicle fluid versus anovulatory side follicle fluid. As we expected, the function classification and enrichment results indicate that up- and down-regulated proteins are largely related to oocyte meiosis, maturation and ovulation. Noticeably, among 9 up-regulated DAPs in ovulatory side follicle fluid, as the DAP with the greatest fold change, PLA2G1B may be a newly discovered component that influences the efficacy of horse IVM/IVF. The current findings add to our knowledge of the in vivo conditions and regulation of equine reproduction, as well as the regulatory mechanism underpinning alternative ovulation.

The role of the oviduct and extracellular vesicles during early embryo development in bovine

The oviduct is an important reproductive structure that connects the ovary to the uterus and takes place to important events such as oocyte final maturation, fertilization and early embryonic development. Thus, gametes and embryo can be directly influenced by the oviductal microenvironment composed by epithelial cells such secretory and ciliated cells and oviductal fluid. The oviduct composition is anatomically dynamic and is under ovarian hormones control. The oviductal fluid provides protection, nourishment and transport to gametes and embryo and allows interaction to oviductal epithelial cells. All these functions together allows the oviduct to provides the ideal environment to the early reproductive events. Extracellular vesicles (EVs) are biological nanoparticles that mediates cell communication and are present at oviductal fluid and plays an important role in gametes/embryo - oviductal cells communication. This review will present the ability of the oviducts based on its dynamic and systemic changes during reproductive events, as well as the contribution of EVs in this process.

Spatial and Pregnancy-Related Changes in the Protein, Amino Acid, and Carbohydrate Composition of Bovine Oviduct Fluid

Knowledge of how the biochemical composition of the bovine oviduct is altered due to the oviduct anatomy or the presence of an embryo is lacking. Thus, the aim of this study was to assess the effect of (І) oviduct anatomy and (ІІ) embryo presence on oviductal fluid (OF) protein, amino acid, and carbohydrate composition. Cross-bred beef heifers (n = 19) were synchronized and those in standing estrus were randomly allocated to a cyclic (non-bred) or pregnant (artificially inseminated) group. All heifers were slaughtered on Day 3 after estrus. The oviducts ipsilateral to the corpus luteum from each animal were isolated, straightened and cut, separating ampulla and isthmus. Each portion was flushed with 500 µl of PBS enabling recovery of the oocyte/embryo. Recovered unfertilized oocytes (cyclic group) and embryos (8-cell embryos; pregnant group) were located in the isthmus of the oviduct. Samples of flushing medium from the isthmus and ampulla were used for proteomic (n = 2 per group), amino acid (n = 5), and carbohydrate (n = 5) analysis. For proteomic analysis, total protein from cyclic and pregnant samples were labelled with different cyanine fluorescent probes and separated according to the isoelectric point using immobilized pH gradient strips (pH 3-10, 17 cm, Protean® IEF cell system, Bio Rad). Second dimension was performed in a polyacrylamide gel (12%) in the presence of SDS using a Protean II XL system (Bio Rad). Images were obtained with a Typhoon 9410 scanner and analyzed with Progenesis SameSpots software v 4.0. Amino acid content in the OF was determined by high performance liquid chromatography (HPLC). Glucose, lactate, and pyruvate were quantified using microfluorometric enzyme-linked assays. For the proteomic assessment, the results of the image analysis were compared by ANOVA. For both amino acid and carbohydrate analyses, statistical analysis was carried out by 2-way ANOVA with the Holm-Sidak nonparametric post hoc analysis. On Day 3 post-estrus, OF composition varied based on (І) anatomical region, where isthmic metabolites were present in lower (i.e., lactate, glycine, and alanine) or higher (i.e., arginine) concentrations compared to the ampulla; and (ІІ) embryo presence, which was correlated with greater, arginine, phosphoglycerate kinase 1, serum albumin, α-1-antiproteinase and IGL@ protein concentrations. In conclusion, data indicate that the composition of bovine OF is anatomically dynamic and influenced by the presence of an early embryo.

Composing the Early Embryonic Microenvironment: Physiology and Regulation of Oviductal Secretions

The oviductal fluid is the first environment experienced by mammalian embryos at the very beginning of life. However, it has long been believed that the oviductal environment was not essential for proper embryonic development. Successful establishment of in vitro embryo production techniques (which completely bypass the oviduct) have reinforced this idea. Yet, it became evident that in vitro produced embryos differ markedly from their in vivo counterparts, and these differences are associated with lower pregnancy outcomes and more health issues after birth. Nowadays, researchers consider the oviduct as the most suitable microenvironment for early embryonic development and a substantial effort is made to understand its dynamic, species-specific functions. In this review, we touch on the origin and molecular components of the oviductal fluid in mammals, where recent progress has been made thanks to the wider use of mass spectrometry techniques. Some of the factors and processes known to regulate oviductal secretions, including the embryo itself, as well as ovulation, insemination, endogenous and exogenous hormones, and metabolic and heat stress, are summarized. Special emphasis is laid on farm animals because, owing to the availability of sample material and the economic importance of fertility in livestock husbandry, a large part of the work on this topic has been carried out in domestic animals used for dairy and/or meat production.

Proteomic analysis of sheep uterus reveals its role in prolificacy

Small Tail Han sheep have attracted attention for their high fecundity and year-round estrus. However, the molecular mechanisms of this fecundity are unknown. Polymorphism of the FecB gene has been shown to be associated with the ovulation rate and litter size in sheep. In this study, we used tandem mass tag quantitative proteomic techniques to identify the differentially abundant proteins in polytocous and monotocous Small Tail Han sheep (FecB++) uterine tissues in the follicular and luteal phases. In total, 41 and 43 differentially abundant proteins were identified in the follicular and luteal phases, respectively. Correlation analysis between the transcriptome and proteome revealed a positive correlation at the two omics levels of prolificacy. GO and KEGG pathway analyses indicated that the mRNAs and proteins upregulated in the polytocous group relative to the monotocous group are involved in sphingolipid metabolism and amino acid metabolism, and may be important in maintaining uterine functions and increasing the embryo survival rate during the estrus cycle of polytocous sheep. In conclusion, our work provides a prospective understanding of the molecular mechanism underlying the high prolificacy of Small Tail Han sheep. SIGNIFICANCE: Fecundity critically affects the profitability of sheep production, but the genetic mechanism of high-prolificacy is still unclear in sheep. We identified potential signaling pathways and differentially abundant proteins associated with reproductive performance through a combination of sheep uterus tissues proteome and transcriptome analyses. These findings will facilitate a better revealing the mechanism and provide possible targets for molecular design breeding for the formation of polytocous traits in sheep.

Seminal plasma proteins and their relationship with sperm motility and morphology in boars

The identification of biomarkers associated with seminal traits could aid in the selection of higher quality ejaculates and benefit the swine industry. The objective of this study was to identify boar seminal plasma proteins associated with sperm motility and morphology. Twenty ejaculates from fifteen adult boars from a commercial boar stud were used for this work. After routine semen collection and analysis, ejaculates were classified into two groups: high-quality semen (HQS) and low-quality semen (LQS), based on sperm motility and morphology. Semen samples were processed for seminal plasma separation and analysis by 2D SDS-PAGE. Total and progressive sperm motility differed between groups (p < 0.001), as well sperm morphology (p < 0.05). The intensity of spots identified as Major seminal plasma PSP-I (PSP-I) and cathepsin B (CTSB) was higher in LQS as compared to HQS samples (p < 0.05). Also, PSP-I was positively associated with major and sperm cauda defects. Sperm motility was negatively correlated with both PSP-I and cathepsin B. We conclude that high concentrations of Major seminal plasma PSP-I and cathepsin B in boar seminal plasma are associated with reduced total and progressive sperm motility and low sperm morphology and might be used as biomarkers for semen quality.