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The Veterinary Record Nov 2020Reproductive efficiency after hydrometra (HD) treatment is usually unsatisfactory.
BACKGROUND
Reproductive efficiency after hydrometra (HD) treatment is usually unsatisfactory.
METHODS
To identify mechanisms involved in low reproductive efficiency of HD-treated goats, pluriparous dairy goats treated for HD (n=10, HD) or with no reproductive disorders (n=11, control: CONT) were induced to oestrus and superovulated. Goats were mated with fertile bucks and seven days after oestrus, non-surgical embryo recovery was performed. Embryos were evaluated and gene expression was performed.
RESULTS
There were no differences (P>0.05) in sexual behaviour parameters, superovulation response, mean number of retrieved structures and viable embryos between groups; although embryo recovery rate was higher (P=0.01) in CONT group. Structures in delayed stage (8-16 cells) were more frequent (P<0.05) in HD (29 vs 1 per cent) goats, as well as the percentage of advanced embryos was greater (P<0.05) for CONT (59.3 vs 33.3 per cent) goats. However, the expression of genes related to apoptosis ( and ), trophectoderm differentiation () and pluripotency maintenance () was not affected (P>0.05) in embryos that reached the morulae and blastocyst stages.
CONCLUSION
Although the HD embryos that developed to morula and blastocyst stages showed no change in the expression of genes related to their quality and implantation capacity, overall, embryo development was impaired in HD-treated goats.
Topics: Animals; Dairying; Embryo Transfer; Embryonic Development; Female; Goat Diseases; Goats; Reproduction; Superovulation; Uterine Diseases
PubMed: 32839201
DOI: 10.1136/vr.105906 -
The Journal of Reproduction and... Oct 2020This study aimed to determine if lactation can be induced by exogenous hormonal treatment in non-pregnant sows. In experiment 1, pseudopregnant animals were divided into...
This study aimed to determine if lactation can be induced by exogenous hormonal treatment in non-pregnant sows. In experiment 1, pseudopregnant animals were divided into four groups and given: 1) 5 mg of estradiol dipropionate (EDP) 5 days before (n = 4), 2) 5 mg of EDP 10 days before (n = 3), 3) 10 mg of EDP 5 days before (n = 3) or 4) 10 mg of EDP 10 days (n = 3) before PGF treatment. Artificial lactation was induced in seven pseudopregnant sows (53.8%) by exogenous hormonal treatment. There was no significant effect of either an increased EDP dosage or interval from the EDP treatment to PGF treatment on the induction rate of artificial lactation. In experiment 2, milk samples were collected from artificial lactating and natural lactating sows (n = 6). IgG and IgA levels in the milk collected from both groups were significantly associated with time during the experimental period. Milk IgG levels 24 h after PGF treatment in artificial lactating sows were higher than those in the colostrum of lactating sows. In experiment 3, hormonal profiles in pseudopregnant sows with (n = 3) or without (n = 3) EDP treatment were determined. There was a significant difference in estradiol-17β levels on days 8, 7 and 5 before PGF treatment between groups. Progesterone and prolactin concentrations did not differ between groups. The present study revealed for the first time that lactation could be induced by exogenous hormonal treatment in non-pregnant sows and that the milk collected from these sows contained high immunoglobulin levels.
Topics: Animals; Colostrum; Estradiol; Estrus; Estrus Synchronization; Female; Hormones; Immunoglobulin A; Immunoglobulin G; Lactation; Milk; Progesterone; Pseudopregnancy; Swine
PubMed: 32595196
DOI: 10.1262/jrd.2020-034 -
Journal of Neuroendocrinology Jul 2023Sleep disruptions are a common occurrence during the peripartum period. While physical and environmental factors associated with pregnancy and newborn care account for...
Sleep disruptions are a common occurrence during the peripartum period. While physical and environmental factors associated with pregnancy and newborn care account for some sleep disruptions, there is evidence that peripartum fluctuations in estrogens may independently impact sleep. However, the impact of these large fluctuations in estrogens on peripartum sleep is unclear because it is difficult to tease apart the effects of estrogens on sleep from effects associated with the growth and development of the fetus or parental care. We therefore used a hormone-simulated pseudopregnancy (HSP) in female Syrian hamsters to test the hypothesis that pregnancy-like increases in estradiol decrease sleep in the absence of other factors. Adult female Syrian hamsters were ovariectomized and given daily hormone injections that simulate estradiol levels during early pregnancy, late pregnancy, and the postpartum period. Home cage video recordings were captured at seven timepoints and videos were analyzed for actigraphy. During "late pregnancy," total sleep time and sleep efficiency were decreased in hormone-treated animals during the white light period compared to pretest levels. Likewise, during "late pregnancy," locomotion was increased in the white light period for hormone-treated animals compared to pretest levels. These changes continued into the "postpartum period" for animals who continued to receive estradiol treatment, but not for animals who were withdrawn from estradiol. At the conclusion of the experiment, animals were euthanized and cFos expression was quantified in the ventral lateral preoptic area (VLPO) and lateral hypothalamus (LH). Animals who continued to receive high levels of estradiol during the "postpartum" period had significantly more cFos in the VLPO and LH than animals who were withdrawn from hormones or vehicle controls. Together, these data suggest that increased levels of estradiol during pregnancy are associated with sleep suppression, which may be mediated by increased activation of hypothalamic nuclei.
Topics: Cricetinae; Animals; Pregnancy; Female; Estradiol; Mesocricetus; Pseudopregnancy; Estrogens; Sleep
PubMed: 37127859
DOI: 10.1111/jne.13278 -
Cell Proliferation Feb 2021In mammals, early pregnancy is a critical vulnerable period during which complications may arise, including pregnancy failure. Establishment of a maternal endometrial...
BACKGROUND
In mammals, early pregnancy is a critical vulnerable period during which complications may arise, including pregnancy failure. Establishment of a maternal endometrial acceptance phenotype is a prerequisite for semiheterogeneous embryo implantation, comprising the rate-limiting step of early pregnancy.
METHODS
Confocal fluorescence, immunohistochemistry and western blot for nuclear and cytoplasmic protein were used to examine the activation of yes-associated protein (YAP) in uterine tissue and primary endometrial cells. The target binding between miR16a and YAP was verified by dual-luciferase reporter gene assay. The mouse pregnancy model and pseudopregnancy model were used to investigate the role of YAP in the maternal uterus during early pregnancy in vivo.
RESULTS
We showed that YAP translocates into the nucleus in the endometrium of cattle and mice during early pregnancy. Mechanistically, YAP acts as a mediator of ECM rigidity and cell density, which requires the actomyosin cytoskeleton and is partially dependent on the Hippo pathway. Furthermore, we found that the soluble factor IFNτ, which is a ruminant pregnancy recognition factor, also induced activation of YAP by reducing the expression of miR-16a.
CONCLUSIONS
This study revealed that activation of YAP is necessary for early pregnancy in bovines because it induced cell proliferation and established an immunosuppressive local environment that allowed conceptus implantation into the uterine epithelium.
Topics: Adaptor Proteins, Signal Transducing; Animals; Antagomirs; Cattle; Cell Cycle Proteins; Endometrium; Epithelial Cell Adhesion Molecule; Extracellular Matrix; Female; Gene Expression; Hippo Signaling Pathway; Interferon Type I; Male; Mice; MicroRNAs; Muscle Proteins; Pregnancy; Pregnancy Proteins; Protein Serine-Threonine Kinases; RNA Interference; RNA, Small Interfering; Signal Transduction; Uterus; YAP-Signaling Proteins
PubMed: 33393124
DOI: 10.1111/cpr.12976 -
Biology of Reproduction Mar 2021Among a wide diversity of sexually reproducing species, male ejaculates coagulate to form what has been termed a copulatory plug. A number of functions have been...
Among a wide diversity of sexually reproducing species, male ejaculates coagulate to form what has been termed a copulatory plug. A number of functions have been attributed to copulatory plugs, including the inhibition of female remating and the promotion of ejaculate movement. Here we demonstrate that copulatory plugs also influence the likelihood of implantation, which occurs roughly 4 days after copulation in mice. Using a bead transfer method to control for differences in ejaculate retention and fertilization rates, we show that implantation rates significantly drop among females mated to genetically engineered males incapable of forming plugs (because they lack functional transglutaminase 4, the main enzyme responsible for its formation). Surprisingly, this result does not correlate with differences in circulating progesterone levels among females, an important hormone involved in implantation. We discuss three models that connect male-derived copulatory plugs to implantation success, including the hypothesis that plugs contribute to a threshold amount of stimulation required for females to become receptive to implantation.
Topics: Animals; Copulation; Ejaculation; Embryo Implantation; Female; Male; Mice; Mice, Knockout; Pregnancy; Transglutaminases
PubMed: 33355341
DOI: 10.1093/biolre/ioaa228 -
Animal Reproduction Oct 2019Progesterone plays an important role in the reproductive function and follicular development in mammals. The aim of the present study was to examine the localization of...
Progesterone plays an important role in the reproductive function and follicular development in mammals. The aim of the present study was to examine the localization of progesterone receptor alpha (PRA) in ovary of pseudopregnant rabbit by immunohistochemical methods. Samples were collected from 14 h. to 18 days of pseudopregnancy. At the first stage of pseudopregnancy (14 h.), the rabbit ovary showed moderate immunostaining of PRA in the granulosa cells and theca interna cells of preovulatory follicle and in the stroma cells. At the middle stage of pseudopregnancy (3-7 days), the rabbit ovary showed strong immunostaining of PRA in ovarian surface epithelial cells, follicular cells of the primary follicle, granulosa cells and theca interna cells of the growing and antral follicles. Moderate immunoexpression of PRA were observed in the large lutein cells and endothelial cells of the corpus haemorrhagicum and corpus luteum and in the stroma cells. At the end of pseudopregnancy (18 days) strong PRA reactions were detected in the small lutein cells of the regressed corpus luteum. Moderate to strong PRA immuno-expression were observed in the proliferated theca interna cells of the atretic antral follicles. The atretic large lutein cells of the regressed corpus luteum showed negative immunostaining for PRA. This study showed that the PRA positive small lutein cells of the regressed corpus luteum and the PRA positive proliferated theca interna cells of the atretic antral follicles were transformed into PRA positive interstitial gland cells. In conclusion, the present study had described the distribution of PRA in the ovary of pseudopregnant rabbit, which is not discussed before in the available literature. It also gives more information about follicular dynamic, formation and origin of interstitial glands, mechanism of ovulation, formation and regression of the corpus luteum.
PubMed: 33224291
DOI: 10.21451/1984-3143-AR2018-0128 -
Current Medical Science Dec 2019Embryo implantation is a complicated physiological process tightly regulated by multiple biological molecules including growth factors. Transforming growth factor-betas...
Embryo implantation is a complicated physiological process tightly regulated by multiple biological molecules including growth factors. Transforming growth factor-betas (TGF-βs) and their most specific signal transduction factors, Smads, are expressed in the endometrium during the window of implantation. Recent researches indicated that Smad dependent TGF-β signaling may play an important role in the process of embryo implantation. In this study, we measured the expression of TGF-β1, TGF-β receptor type I (TβRI), Smad3 and p-Smad3 in the endometrium of mice and observed their elevation on day 4, 5 and 6 of pseudopregnancy. Then we administrated a specific Smad3 inhibitor (Sis3) into the uterine cavity of mice on day 3 of pregnancy. The results showed a reduction in insulin-like growth factor-1 (IGFBP-1) expression and the decreased number of implanted embryo after the administration. In addition, Sis3 was found to reduce the IGFBP-1 secretion in decidualized endometrial stromal cells. Taken all together, our findings demonstrated that TGF-β/Smad3 signaling is involved in the process of embryo implantation.
Topics: Animals; Embryo Implantation; Female; Isoquinolines; Mice; Phosphorylation; Pregnancy; Pyridines; Pyrroles; Receptor, Transforming Growth Factor-beta Type I; Signal Transduction; Smad3 Protein; Transforming Growth Factor beta1; Up-Regulation; Uterus
PubMed: 31845233
DOI: 10.1007/s11596-019-2134-z -
Oxidative Medicine and Cellular... 2021The increase of oxidative stress is one of the important characteristics of mammalian luteal regression. Previous investigations have revealed the essential role of...
The increase of oxidative stress is one of the important characteristics of mammalian luteal regression. Previous investigations have revealed the essential role of reactive oxygen species (ROS) in luteal cell death during luteolysis, while it is unknown how ROS is regulated in this process. Considering the decrease of blood flow and increase of PGF during luteolysis, we hypothesized that the HIF-1 pathway may be involved in the regulation of ROS in the luteal cell of the late corpus luteum (CL). Here, by using a pseudopregnant rat model, we showed that the level of both HIF-1 and its downstream BNIP3 was increased during luteal regression. Consistently, we observed the increase of autophagy level during luteolysis, which is regulated in a Beclin1-independent manner. Comparing with early (Day 7 of pseudopregnancy) and middle CL (Day 14), the level of ROS was significantly increased in late CL, indicating the contribution of oxidative stress in luteolysis. Inhibition of HIF-1 by echinomycin (Ech), a potent HIF-1 inhibitor, ameliorated the upregulation of BNIP3 and NIX, as well as the induction of autophagy and the accumulation of ROS in luteal cells on Day 21 of pseudopregnancy. Morphologically, Ech treatment delayed the atrophy of the luteal structure at the late-luteal stage. An in vitro study indicated that inhibition of HIF-1 can also attenuate PGF -induced ROS and luteal cell apoptosis. Furthermore, the decrease of cell apoptosis can also be observed by ROS inhibition under PGF treatment. Taken together, our results indicated that HIF-1 signaling is involved in the regression of CL by modulating ROS production via orchestrating autophagy. Inhibition of HIF-1 could obviously hamper the apoptosis of luteal cells and the process of luteal regression.
Topics: Animals; Corpus Luteum; Female; Hypoxia-Inducible Factor 1, alpha Subunit; Luteolysis; Pregnancy; Pseudopregnancy; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species
PubMed: 34512862
DOI: 10.1155/2021/1764929 -
Biochemical and Biophysical Research... Jan 2020Neuromedin U (NMU) has a precursor that contains one additional peptide consisting of 33 or 36 amino acid residues. Recently, we identified this second peptide from rat...
Neuromedin U (NMU) has a precursor that contains one additional peptide consisting of 33 or 36 amino acid residues. Recently, we identified this second peptide from rat brain and designated it neuromedin U precursor-related peptide (NURP), showing it to stimulate prolactin release from the pituitary when injected via the intracerebroventricular (icv) route. Here, we examined whether NMU, like NURP, also stimulates prolactin release. Unlike NURP, icv injection of NMU significantly decreased the secretion of prolactin from the pituitary. This suppression of prolactin release by NMU was observed in hyper-prolactin states such as lactation, stress, pseudopregnancy, domperidone (dopamine antagonist) administration, and icv injection of NURP. Immunohistochemical analysis revealed that icv injection of NMU induced cFos expression in dopaminergic neurons of the arcuate nucleus, but not the substantia nigra. Mice with double knockout of NMU and neuromedin S (NMS), the latter also binding to NMU receptors, showed a significant increase of the plasma prolactin level after domperidone treatment relative to wild-type mice. These results suggest that NMU and NURP may play important reciprocal roles in physiological prolactin secretion.
Topics: Animals; Arcuate Nucleus of Hypothalamus; Dopaminergic Neurons; Mice; Neuropeptides; Pituitary Gland; Prolactin; Proto-Oncogene Proteins c-fos; Rats; Receptors, Neurotransmitter
PubMed: 31677791
DOI: 10.1016/j.bbrc.2019.10.156 -
PloS One 2020Endocrine profiling is an increasingly utilized tool for detecting pregnancies in wild populations of mammals. Given the difficulty in calculating reproductive rates of...
Endocrine profiling is an increasingly utilized tool for detecting pregnancies in wild populations of mammals. Given the difficulty in calculating reproductive rates of Pacific walruses (Odobenus rosmarus divergens) the use of endocrine techniques for determining pregnancy rates could be particularly useful for management of the population. The goals of this study were to 1) determine if progesterone and total estrogen concentrations in ovarian tissues of female walruses could be used to determine reproductive state and 2) determine if walruses undergo a functional postpartum estrus, as is seen in other pinnipeds. Ovaries were collected from female walruses (n = 13) hunted in subsistence hunts by Alaska Native communities. Females were categorized as postpartum, full-term pregnant, pregnant diapause or unbred. Total estrogen concentrations were greatest in unbred (n = 2) and pregnant (n = 2) females. Progesterone concentrations were also nominally larger in unbred (n = 2) than pregnant (n = 2) and postpartum (n = 9) animals. Small samples sizes precluded the use of statistical comparisons among groups. Corpora lutea tissue samples in this study did not reflect the presence of a postpartum estrus in the month of May as postpartum females yielded lower total estrogen concentrations than unbred or pregnant animals. Both unbred animals were in a state of pseudopregnancy, which has not been physiologically described for this species before. The progesterone profiles in late (59 ng/g) and early (140 ng/g) pregnancy were lower than expected and fell within the range of the postpartum females (36-210 ng/g), suggesting low production of the hormone by the corpus luteum during these phases of pregnancy. Profiling reproductive hormones in free-ranging walruses demonstrates that an endocrine approach may be a valuable tool for determining reproductive status of females, however increased sample sizes and time of year must be considered to accurately separate pregnant versus pseudopregnant individuals.
Topics: Animals; Biomarkers; Estrogens; Female; Progesterone; Pseudopregnancy; Walruses
PubMed: 32931507
DOI: 10.1371/journal.pone.0239218