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The Journal of Reproduction and... Dec 2017In embryo transfer experiments in mice, pseudopregnant females as recipients are prepared by sterile mating with vasectomized males. Because only females at the...
In embryo transfer experiments in mice, pseudopregnant females as recipients are prepared by sterile mating with vasectomized males. Because only females at the proestrus stage accept males, such females are selected from a stock of animals based on the appearance of their external genital tract. Therefore, the efficiency of preparing pseudopregnant females largely depends on the size of female colonies and the skill of the operators who select females for sterile mating. In this study, we examined whether the efficiency of preparing pseudopregnant females could be improved by applying an estrous cycle synchronization method by progesterone (P4) pretreatment, which significantly enhances the superovulation outcome in mice. We confirmed that after two daily injections of P4 (designated Days 1 and 2) in randomly selected females, the estrous cycles of most females (about 85%) were synchronized at metestrus on Day 3. When P4-treated females were paired with vasectomized males for 4 days (Days 4-8), a vaginal plug was found in 63% (20/32) of the females on Day 7. After the transfer of vitrified-warmed embryos into their oviducts, 52% (73/140) of the embryos successfully developed into offspring, the rate being comparable to that of the conventional embryo transfer procedure. Similarly, 77% (24/31) of females became pregnant by fertile mating with intact males for 3 days, which allowed the scheduled preparation of foster mothers. Thus, our estrous cycle synchronization method may omit the conventional experience-based process of visually observing the vagina to choose females for embryo transfer. Furthermore, it is expected that the size of female stocks for recipients can be reduced to less than 20%, which could be a great advantage for facilities/laboratories undertaking mouse-assisted reproductive technology.
Topics: Animals; Embryo Transfer; Estrus Synchronization; Female; Male; Pregnancy; Progesterone; Pseudopregnancy
PubMed: 28824024
DOI: 10.1262/jrd.2017-068 -
Journal of Anatomy Jul 2017The formation of a placenta is critical for successful mammalian pregnancy and requires remodelling of the uterine epithelium. In eutherian mammals, remodelling involves...
The formation of a placenta is critical for successful mammalian pregnancy and requires remodelling of the uterine epithelium. In eutherian mammals, remodelling involves specific morphological changes that often correlate with the mode of embryonic attachment. Given the differences between marsupial and eutherian placentae, formation of a marsupial placenta may involve patterns of uterine remodelling that are different from those in eutherians. Here we present a detailed morphological study of the uterus of the brushtail possum (Trichosurus vulpecula; Phalangeridae) throughout pregnancy, using both scanning and transmission electron microscopy, to identify whether uterine changes in marsupials correlate with mode of embryonic attachment as they do in eutherian mammals. The uterine remodelling of T. vulpecula is similar to that of eutherian mammals with the same mode of embryonic attachment (non-invasive, epitheliochorial placentation). The morphological similarities include development of large apical projections, and a decrease in the diffusion distance for haemotrophes around the period of embryonic attachment. Importantly, remodelling of the uterus in T. vulpecula during pregnancy differs from that of a marsupial species with non-invasive attachment (Macropus eugenii; Macropodidae) but is similar to that of a marsupial with invasive attachment (Monodelphis domestica; Didelphidae). We conclude that modes of embryonic attachment may not be typified by a particular suite of uterine changes in marsupials, as is the case for eutherian mammals, and that uterine remodelling may instead reflect phylogenetic relationships between marsupial lineages.
Topics: Animals; Female; Ovary; Placentation; Pregnancy; Pregnancy, Animal; Pseudopregnancy; Trichosurus; Uterus
PubMed: 28397980
DOI: 10.1111/joa.12610 -
The Journal of Endocrinology Apr 2017Embryo implantation and endometrial decidualization are critical events that occur during early pregnancy in humans and mice, and perturbation in either can result in...
Embryo implantation and endometrial decidualization are critical events that occur during early pregnancy in humans and mice, and perturbation in either can result in infertility. WNT signaling through the canonical β-catenin pathway plays a pivotal role in embryonic Müllerian duct development, postnatal uterine maturation and establishment of pregnancy. Loss of β-catenin in the Müllerian duct mesenchyme (MDM)-derived stroma and myometrium results in impaired decidualization and infertility, whereas gain-of-function (GOF) results in the formation of mesenchymal tumors and sub-fertility attributed to malformed oviducts. We hypothesized that GOF β-catenin further contributes to sub-fertility through improper stromal and epithelial cell signaling during embryo implantation and decidualization. We show that mice with GOF β-catenin in MDM-derived stroma and myometrium have reduced implantation sites after embryo transfer and decreased decidualization. On day 4.5 of pseudopregnancy or in mice treated with progesterone and estrogen to mimic early pregnancy, the estrogen-LIF-ERK and progesterone-IHH pathways remain predominantly intact in GOF β-catenin mice; however, JAK/STAT signaling is altered. pSTAT3 is significantly reduced in GOF β-catenin mice and expression of downstream epithelial junctional complex factors, and , is increased. We also show that purified stromal cells from GOF β-catenin uteri, when removed from epithelial cell influence and provided with the appropriate hormonal stimuli, are able to decidualize indicating that the cells are intrinsically capable of decidualization. Taken together, these results suggest that dysregulated β-catenin activity in the stroma affects epithelial cell STAT3 signaling and ultimately embryo implantation and stromal decidualization.
Topics: Animals; Decidua; Embryo Implantation; Epithelial Cells; Estradiol; Female; Mice; Mice, Transgenic; Phosphorylation; Progesterone; Pseudopregnancy; STAT3 Transcription Factor; Signal Transduction; Uterus; beta Catenin
PubMed: 28183999
DOI: 10.1530/JOE-16-0502 -
Paediatric and Perinatal Epidemiology Jan 2017Epidemiologic studies examining preconception risk factors on perinatal outcomes are typically restricted to livebirths. By including only non-terminated pregnancies,...
BACKGROUND
Epidemiologic studies examining preconception risk factors on perinatal outcomes are typically restricted to livebirths. By including only non-terminated pregnancies, estimates for the underlying pregnancy cohort may be subject to selection bias. We examined if potential selection bias due to induced termination by maternal race may result in different estimates of the non-Hispanic black - non-Hispanic white risk ratio (RR) for preterm delivery (PTD) among a reconstructed pregnancy cohort ('pseudo-pregnancy cohort').
METHODS
Using New York City registries of 1.6 million livebirths, spontaneous terminations, and induced terminations among non-Hispanic black and non-Hispanic white women (2000-12), we multiply imputed PTD (<37 weeks) and early PTD (<32 weeks) outcomes for induced terminations based on maternal race, age, parity, marital status, nativity, and medical care payer to construct the pseudo-pregnancy cohort.
RESULTS
Among non-Hispanic black and non-Hispanic white women, 55% and 19% of pregnancies ended in induced termination and 13% and 8% resulted in PTD, respectively. Although several factors were associated with both PTD and induced termination, PTD RRs in the birth (RR 1.64, 95% confidence interval (CI) 1.62, 1.66) and pseudo-pregnancy (RR 1.63, 95% CI 1.56, 1.71) cohorts were similar. However, early PTD RR was somewhat larger in the birth (RR 2.80, 95% CI 2.71, 2.89) than pseudo-pregnancy (RR 2.47, 95% CI 2.23, 2.73) cohort.
CONCLUSIONS
Using birth certificate data - thereby excluding induced terminations - to estimate the PTD racial disparity did not produce biased estimates. Our data suggest observed PTD disparities likely are not artefacts of selection bias due to induced termination.
Topics: Abortion, Induced; Adult; Cohort Studies; Ethnicity; Female; Healthcare Disparities; Humans; Infant, Newborn; Insurance, Health; Maternal-Child Health Services; New York City; Parity; Population Surveillance; Pregnancy; Pregnancy Outcome; Pregnant Women; Premature Birth; Selection Bias; Young Adult
PubMed: 27794171
DOI: 10.1111/ppe.12322 -
Reproductive Biology and Endocrinology... Oct 2016Cyclooxygenase (COX)-derived prostanoids (PGE PGI) are important contributors to the process of decidualization. Previous studies showed the presence of Ang-(1-7) in the...
BACKGROUND
Cyclooxygenase (COX)-derived prostanoids (PGE PGI) are important contributors to the process of decidualization. Previous studies showed the presence of Ang-(1-7) in the primary and secondary decidualized zones of the implantation site at early pregnancy. Decreased concentrations of Ang-(1-7) were found in the decidualized uterus compared to the non-decidualized uterus of pseudopregnant rats, suggesting that low levels of Ang-(1-7) are required for successful decidualization at early pregnancy.
METHODS
To understand the role of Ang-(1-7) in prostaglandin production in a decidualized uterus, induced by a bolus injection of sesame oil, Ang-(1-7) (24 μg/kg/h) or vehicle was then infused directly into the decidualized uterine horn using an osmotic minipump. The right horns were not injected or infused and served as non-decidualized uterine horns in both groups of animals.
RESULTS
Decidualization increased PGE concentration in the uterus (0.53 ± 0.05 vs. 12.0 ± 3.2 pmol/mg protein, p < 0.001, non-decidualized vs. decidualized horns); Ang-(1-7) infusion attenuated the increase of PGE (12.0 ± 3.2 vs. 5.1 ± 1.3 pmol/mg protein, p < 0.01 control vs. Ang-(1-7) treated decidualized horns). The stable metabolite of PGI (6-keto PGF) was increased with decidualization (0.79 ± 0.17 vs. 3.5 ± 0.82 pmol/mg protein, p < 0.001, non-decidualized vs. decidualized horns). Ang-(1-7) infusion attenuated the increase in 6-keto PGF in the decidualized horn (3.5 ± 0.82 vs 1.8 ± 0.37 pmol/mg protein, p < 0.05 control vs. Ang-(1-7) treated decidualized horns). The circulating levels of 6-keto-PGF and TXB were decreased by Ang-(1-7) infusion, while no difference was observed in circulating PGE. Although the global assessment of cleaved caspase 3 immunostaining, a marker of apoptosis, was unchanged within the Ang-(1-7) decidualized horn, there were localized decreases in cleaved caspase 3 staining in the luminal region in the decidualized uterus of Ang-(1-7)-treated rats.
CONCLUSIONS
These studies show that increased local uterine Ang-(1-7) alters the uterine prostaglandin environment, possibly leading to disruptions of early events of decidualization.
Topics: 6-Ketoprostaglandin F1 alpha; Angiotensin I; Animals; Decidua; Dinoprostone; Female; Peptide Fragments; Pregnancy; Pseudopregnancy; Rats; Rats, Sprague-Dawley; Uterus
PubMed: 27756404
DOI: 10.1186/s12958-016-0202-9 -
Reproductive Biology and Endocrinology... Oct 2016ATF6α, one of the sensor proteins in the stress signaling pathway of the endoplasmic reticulum, is located in the membrane of the endoplasmic reticulum. To date, the...
BACKGROUND
ATF6α, one of the sensor proteins in the stress signaling pathway of the endoplasmic reticulum, is located in the membrane of the endoplasmic reticulum. To date, the physiological function of ATF6α in the process of embryo implantation has not been reported.
METHODS
In this study, the expression pattern of ATF6α in the mouse uterus during peri-implantation and the estrous cycle was detected by real-time PCR, western blot and immunohistochemistry.
RESULTS
ATF6α mRNA and protein levels were higher in the uterus near the implantation site on day 5 and were intensely expressed in the secondary decidual zone (SDZ) on days 7-8. In the uteri of pseudopregnant mice, ATF6α mRNA and protein levels were lower on day 5 than on other days. The activating blastocyst and artificial decidualization had an obvious effect of increasing the expression of ATF6α. In addition, the expression of ATF6α was affected by progesterone (P) and estrogen (E) in ovariectomized mice. This finding is further supported by evidence from mice during the estrous cycle.
CONCLUSIONS
Thus, we have concluded that ATF6α may play an important role during embryo implantation and decidualization.
Topics: Activating Transcription Factor 6; Animals; Embryo Implantation; Estrous Cycle; Female; Gene Expression Regulation, Developmental; Male; Mice; Pregnancy; Pseudopregnancy; RNA, Messenger; Uterus
PubMed: 27717400
DOI: 10.1186/s12958-016-0199-0 -
Experimental and Therapeutic Medicine Oct 2016Stem cell transplantation, which is based on the application of mesenchymal stem/stromal cells (MSCs), is a rapidly developing approach to the regenerative therapy of...
Stem cell transplantation, which is based on the application of mesenchymal stem/stromal cells (MSCs), is a rapidly developing approach to the regenerative therapy of various degenerative disorders characterized by brain and heart failure, as well as skin lesions. In comparison, the use of stem cell transplantations to treat infertility has received less attention. One of the causes of miscarriages and fetal growth delay is the loss of the decidual reaction of endometrial cells. The present study modeled decidualization processes in pseudopregnant rats. For cell transplantation experiments, the rats were transplanted with MSCs established from endometrial fragments in menstrual blood (eMSCs). These cells express common MSC markers, are multipotent and are able to differentiate into various tissue lineages. Cell therapy frequently requires substantial cell biomass, and cultivation of MSCs may be accompanied by significant changes to their properties, including malignant transformation. In order to minimize the potential for malignant transformation, the proliferation of eMSCs was irreversibly suppressed by irradiation and mitomycin C treatment. Transplantation of the rats with viable, non-proliferating eMSCs stimulated the development of all elements of decidual tissue. Conversely, transplantation of the rats with cells killed using 95% ethanol did not result in the development of decidual tissue. The present study demonstrated the potential for applying eMSCs to the cellular therapy of infertility associated with endometrial disorders characterized by decidualization insufficiency and implantation failure. In addition, the transplantation of viable but non-proliferating cells ensured that their oncogenic potential was limited.
PubMed: 27698746
DOI: 10.3892/etm.2016.3671 -
The Journal of Veterinary Medical... Jan 2017Though Fas/Fas ligand (FasL) system-dependent apoptosis is considered to be the primary form of cell death in regressing corpus luteum (CL), the cellular identity and...
Though Fas/Fas ligand (FasL) system-dependent apoptosis is considered to be the primary form of cell death in regressing corpus luteum (CL), the cellular identity and regulation of expression of the ligand and receptor molecules are not fully understood. Here, we focused on immunohistochemical determination of Fas expression during natural regression with comparison of three different types of rat CLs. Detected Fas was in good spatial association with cleaved caspase-3 and FasL proteins and with macrophages and neutrophils. In CLs of the cycle and pseudopregnancy, Fas-positive cell types included large and small luteal (steroidogenic) cells and capillary endothelial cells mainly, and blood-derived immune cells occasionally. Fas signals were abundant at multiple focal inflammatory-like sites. In contrast, Fas signals in CL of pregnancy did not localize in steroidogenic cells, but almost exclusively in endothelial cells and granulocytes. The signals scattered evenly throughout the CL tissue as phagocytes also did. In all CLs types, the numbers of Fas-expressing cells increased transiently after functional inactivation and at the early phase of structural regression. This observation revealed spatio-temporally regulated expression of Fas that was highly associated with apoptotic and phagocytotic systems and type-dependent differences in Fas expression and phagocytes dynamics in naturally regressing CL of rats.
Topics: Animals; Caspase 3; Corpus Luteum; Fas Ligand Protein; Female; Gene Expression Regulation; Luteolysis; Macrophages; Neutrophils; Phagocytes; Pregnancy; Pseudopregnancy; Rats
PubMed: 27546215
DOI: 10.1292/jvms.16-0199 -
The Primary Care Companion For CNS... 2016
Topics: Adult; Bipolar Disorder; Delusions; Female; Humans; Infertility, Female; Pseudopregnancy
PubMed: 27247836
DOI: 10.4088/PCC.15l01833 -
The Journal of Reproduction and... Aug 2016The induction of pseudopregnancy by the exogenous administration of estradiol dipropionate (EDP) was investigated in cyclic Microminipigs (MMpigs) and the effects of...
The induction of pseudopregnancy by the exogenous administration of estradiol dipropionate (EDP) was investigated in cyclic Microminipigs (MMpigs) and the effects of exogenous administration of prostaglandin (PG) F2α on estrus exhibition were assessed in pseudopregnant MMpigs. In experiment 1, ovariectomized MMpigs were given a single intramuscular injection of 0.5, 1.5, or 2.5 mg of EDP. The estradiol-17β level at each of these doses was significantly higher 1 to 3 days after EDP administration than on the day of the injection. In experiment 2, animals were given 1.5 mg of EDP once at 9 to 12 days after the end of estrus (D0) and then no (1.5 mg × 1 group), one (D0 and D4; 1.5 mg × 2 group), or two (D0, D4 and D7; 1.5 mg × 3 group) additional treatments. The pseudopregnancy rate was significantly higher in the 1.5 mg × 3 than in the 1.5 mg × 1 group. In experiment 3, PGF2α was administered twice between 26 and 28 days after EDP treatment to five pseudopregnant gilts with a 24-h interval between the two injections. Estrus after PGF2α treatment and LH surge were observed in 100% and 80% pseudopregnant MMpigs, respectively. The interval from the day of the first PGF2α treatment to the onset of estrus was 6.5 ± 0.2 days. These results indicate that multiple EDP treatments are required for induction of pseudopregnancy in MMpigs and estrus exhibition can be controlled in MMpigs by treatment with EDP and PGF2α.
Topics: Animals; Dinoprost; Estradiol; Estrus Synchronization; Female; Ovariectomy; Pseudopregnancy; Swine; Swine, Miniature
PubMed: 27151362
DOI: 10.1262/jrd.2015-169