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Abstract Seminal plasma (SP), a fluid composed mainly by secretions from accessory sex glands, contains a heterogenous population of extracellular vesicles (EVs), involved in several reproductive physiological processes. Seminal plasma has been found to modulate ovary function, in terms of hormone secretion and immune regulation. This study evaluated the potential effect of SP-EV-subsets on the modulation of cumulus-oocyte-complex (COCs) physiology during in vitro maturation (IVM). Two SP-EV-subsets, small-EVs (S-EVs) and large-EVs (L-EVs), were isolated from pig SP by size-exclusion-chromatography. Next, COCs were IVM in the absence (control) or presence of each SP-EV-subset to evaluate their uptake by COCs (PKH67-EVs labelling) and their effect on oocyte and cumulus cells (CCs) (gene expression, and progesterone and estradiol-17β levels). S-EVs and L-EVs were able to bind CCs but not oocytes. Supplementation with L-EVs induced changes (P ≤ 0.05) in the transcript levels of oocyte maturation- (HAS2) and steroidogenesis-related genes (CYP11A1 and HSD3B1) in CCs. No effect on nuclear oocyte maturation and progesterone and estradiol-17β levels was observed when COCs were IVM with any of the two SP-EV-subsets. In conclusion, while SP-EV-subsets can be integrated by CCs during IVM, they do not affect oocyte maturation and only L-EVs are able to modulate CCs function, mainly modifying the expression of steroidogenesis-related genes.

After breeding or artificial insemination, especially with frozen/thawed semen, mares often develop a persistent uterine inflammation, which is diagnosed by intra-uterine fluid accumulation. Here, we explored whether intra-uterine fluid accumulation affects corpus luteum function and tested the hypothesis that intra-uterine fluid accumulation after artificial insemination alters blood flow in the corpus luteum and plasma progesterone concentrations. A total of 40 Standardbred mares were artificially inseminated with frozen-thawed semen 30 to 36 h after induction of ovulation, and cases with or without intra-uterine fluid accumulation were detected by ultrasound 12 h after insemination. Luteal blood flow was measured by Power Doppler ultrasonography 3 and 6 days after ovulation, progesterone concentration was measured in peripheral plasma by ELISA 6 days after ovulation, and pregnancy was diagnosed by ultrasonography 14 days after ovulation. Luteal blood flow increased between 3 and 6 days after ovulation, but blood flow did not differ significantly between cases with (n = 28) and without (n = 25) intra-uterine fluid accumulation after insemination. Surprisingly, progesterone concentrations were higher in cases of intra-uterine fluid accumulation than cases without (9.3 ± 1.1 vs. 6.6 ± 0.5 ng/mL, p = 0.048). Pregnancy was less likely in cases with intra-uterine fluid accumulation than in cases without (10/28 vs. 17/25, p = 0.019), and there was a negative correlation between the severity of intra-uterine fluid accumulation and per cycle pregnancy rate. These data suggest that although intra-uterine fluid accumulation increases the secretion of progesterone, pregnancy is more dependent on uterine health than ovarian function.

Abstract A scalar theory can have many Gaussian (free) fixed points, corresponding to Lagrangians of the form ϕ□ n ϕ. We use the non-perturbative RG to study examples of flows between such fixed points. We show that the anomalous dimension changes continuously in such a way that at the endpoints the fields have the correct dimensions of the respective free theories. These models exhibit various pathologies, but are nonetheless interesting as examples of theories that are asymptotically free both in the infrared and in the ultraviolet. Furthermore, they illustrate the fact that a diverging coupling can actually correspond to a free theory.

Mechanisms underlying differentiation of good or poor freezability ejaculates in bull are still poorly understood. This study aims at investigating oxidative stress parameters and metabolomic profiling of seminal plasma (SP) in relation to bull semen motility before and after cryopreservation. Semen samples were collected by artificial vagina from 20 bulls aged from 10 to 12 mo. An aliquot of semen was centrifuged to obtain SP (stored at -80°C), another was diluted 1:1 with a pre-warmed extender and cryopreserved. Motility assessment (CASA) was performed on fresh and thawed semen (0 and 3 h after thawing). Semen samples were divided into good freezers (GF) and bad freezers (BF) groups according to thawed semen motility, with cutoff values as follows: TM ≥ 60% and PM ≥ 30%. SP was used for oxidative stress markers analysis by spectroscopy techniques and metabolomic profile by nuclear magnetic resonance (NMR). The relationship between NMR spectra and semen quality was evaluated by the PCA/PLS-DA analysis. General linear models and mixed linear models were used to evaluate the relationship between seminal plasma oxidative stress parameters and semen quality. A clear separation between GF and BF ejaculates was observed on the first two principal components of the variance (PC1 vs PC2) of NMR spectra of SP. The increase of advanced oxidative protein products (AOPP) and thiols concentrations on SP were significantly related with higher straightness (STR), beat cross frequency (BCF) and linearity (LIN) and the decrease of amplitude of lateral head displacement (ALH) of fresh semen. Thiols and AOPP concentrations on SP were positively related to semen freezability. In addition, higher AOPP concentration was significantly related to higher TM, PM and LIN of thawed spermatozoa, whereas higher levels of thiols in SP concentration were positively related to the increment of sperm PM after thawing. These findings suggested that SP composition can modulate bull semen freezabilty. Further analyses could elucidate which metabolites and oxidative stress parameters could be used as biomarkers of good semen quality after cryopreservation. [ABSTRACT FROM AUTHOR]