Protopanaxadiol improves endometriosis associated infertility and miscarriage in sex hormones receptors-dependent and independent manners.

Background: Patients with endometriosis (EMs) have high risks of infertility and spontaneous abortion. How to remodel the fertility of patients with EMs has always been the hot spot and difficulty in the field of reproductive medicine. As an aglycone of ginsenosides, protopanaxadiol (PPD) possesses pleiotropic biological functions and has high medicinal values. We aimed to investigate the effect and potential mechanism of PPD in the treatment of EMs-associated infertility and spontaneous abortion. Methods: The EMs mice models were constructed by allotransplantation. The pregnancy rates, embryo implantation numbers and embryo resorption rates of control and EMs were counted. RNA sequencing, qRT-PCR, enzyme linked immunosorbent assay (ELISA) and FCM analysis were performed to screen and confirm the expression of endometrial receptivity/decidualization-related molecules, inflammation cytokines and NK cell function-related molecules in vitro and/or in vivo. The SWISS Target Prediction, STRING and Cytoscape were carried out to predict the potential cellular sensory proteins, the protein-protein interaction (PPI) network between sensory proteins and fertility-related molecules, respectively. Micro-CT detection, liver and kidney function tests were used to evaluate the safety. Results: Here, we observe that PPD significantly up-regulates endometrial receptivity-related molecules (e.g., Lif, Igfbp1, Mmps, collagens) and restricts pelvic inflammatory response (low levels of IL-12 and IFN-γ) of macrophage, and further remodel and improve the fertility of EMs mice. Additionally, PPD increases the expression of decidualization-related genes and Collagens, and promotes the proliferation, residence, immune tolerance and anagogic functions of decidual NK cells (low levels of CD16 and NKp30, high levels of Ki67, VEGF, TGF-ß) in pregnant EMs mice, and further triggers decidualization, decidual NK cell-mediated maternal-fetal immune tolerance and angiogenesis, preventing pregnant EMs mice from miscarriage. Mechanically, these effects should be dependent on ESRs, PGR and other sensory proteins (e.g., AR). Compared with GnRHa (the clinic first-line drug for EMs), PPD does not lead to the decline of serum estrogen and bone loss. Conclusion: These data suggest that PPD prevents EMs-associated infertility and miscarriage in sex hormones receptors-dependent and independent manners possibly, and provides a potential therapeutic strategy with high efficiency and low side effects to remodels the fertility of patients with EMs.

Diets enriched in PUFAs at an early postimplantation stage prevent embryo resorptions and impaired mTOR signaling in the decidua from diabetic rats.

Maternal diabetes increases the risk of embryo resorptions and impairs embryo development. Decidualization is crucial for embryo development and regulated by mTOR signaling. However, little is known about how maternal diabetes affects the decidua at early postimplantation stages and whether dietary treatments enriched in polyunsaturated fatty acids (PUFAs) can prevent decidual alterations. Here, we determined resorption rates, decidual mTOR pathways and markers of decidual function and remodeling in diabetic rats fed or not with diets enriched in PUFAs exclusively during the early postimplantation period. Pregestational streptozotocin-induced diabetic Albino Wistar rats and controls were fed or not with diets enriched in 6% sunflower oil or 6% chia oil (enriched in n-6 or n-3 PUFAs, respectively) on days 7, 8 and 9 of pregnancy and evaluated on day 9 of pregnancy. Maternal diabetes induced an 11-fold increase in embryo resorptions, which was prevented by both PUFAs-enriched diets despite no changes in maternal glycemia. The activity of mTOR pathway was decreased in the decidua from diabetic rats, an alteration prevented by the PUFAs-enriched diets. PUFAs-enriched diets prevented increased expression of Foxo1 (a negative regulator of mTOR) and reduced expression of miR-21 (a negative regulator of Foxo1). These diets also prevented reduced markers of decidual function (leukemia inhibitory factor and IGFBP1 expression and MMPs activity) in diabetic rat decidua. We identified the early post implantation as a crucial stage for pregnancy success, in which dietary PUFAs can protect diabetic pregnancies from embryo resorptions, decidual mTOR signaling impairments, and altered markers of decidual function and remodeling.

Rescuing lethal phenotypes induced by disruption of genes in mice: a review of novel strategies.

Approximately 35 % of the mouse genes are indispensable for life, thus, global knock-out (KO) of those genes may result in embryonic or early postnatal lethality due to developmental abnormalities. Several KO mouse lines are valuable human disease models, but viable homozygous mutant mice are frequently required to mirror most symptoms of a human disease. The site-specific gene editing systems, the transcription activator-like effector nucleases (TALENs), Zinc-finger nucleases (ZFNs) and the clustered regularly interspaced short palindrome repeat-associated Cas9 nuclease (CRISPR/Cas9) made the generation of KO mice more efficient than before, but the homozygous lethality is still an undesired side-effect in case of many genes. The literature search was conducted using PubMed and Web of Science databases until June 30th, 2020. The following terms were combined to find relevant studies: "lethality", "mice", "knock-out", "deficient", "embryonic", "perinatal", "rescue". Additional manual search was also performed to find the related human diseases in the Online Mendelian Inheritance in Man (OMIM) database and to check the citations of the selected studies for rescuing methods. In this review, the possible solutions for rescuing human disease-relevant homozygous KO mice lethal phenotypes were summarized.

Testing the endometrium: is there enough evidence to justify clinical use?

PURPOSE OF REVIEW: Embryo implantation remains the limiting factor in assisted reproduction outcomes. To date research has mainly focused on improving embryo quality, numbers and selection as the route to improve treatment results. However, with success rates plateauing, interest in the possibility of modulating the endometrial factor is increasing, and a number of biomarkers are now available that offer the possibility of assessing endometrial function. RECENT FINDINGS: In this review, we review recent evidence for the efficacy of a number of these biomarkers, with emphasis on those that aim to enable improvement in embryo/endometrial developmental synchrony endometrium and that offer an assessment of the degree of immune activation of the endometrium. The emerging field of reproductive tract microbiome analysis is also considered. Finally, nascent biomarkers of materno-foetal dialogue, including noncoding RNAs, microvesicles and endometrial glycans are discussed. SUMMARY: Tests of potential clinical value are emerging, but further validation studies are required. The usage of innovative endometrial biomarkers provides the possibility of targeted therapies rather than the blind empirical approaches to face embryo implantation failure. It also enables the possibility of randomized controlled trials of interventions targeting the individual cause rather empirical treatments of undiagnosed recurrent implantation failure.

[The intervention effect of N-carbamoyl glutamic acid on embryo implantation disorder induced by carbon disulfide and its possible molecular mechanism].

Objective: To explore the preventive effect and possible molecular mechanism of dietary supplementation of N-carbamylglutamate (NCG) in the implantation of carbon disulfide (CS(2)) into embryo implantation disorders. Methods: embryo implantation disorder model was established by single intraperitoneal exposure to CS(2) on the 3rd, 4th, and 5th days after pregnancy. Endometrial tissues were collected for 24h after exposure to CS(2) for western-blot and immunohistochemical staining. Results: The number of embryo implantation was increased in NCG+CS(2) group, compared with CS(2) alone group. Day 4 of pregnancy when CS(2)-exposed after 24 h, the expression of pAKT protein in NCG+CS(2) group was significantly increased (P<0.05), the expression level of pAMPK protein in NCG+CS(2) group was significantly decreased, compared with CS(2) alone group, respectively. Immunohistochemical results showed that pAKT, pAMPK, AKT and AMPK proteins were expressed in luminal epithelial cells, glandular epithelial cells and stromal cells of endometrium; Day 4 of pregnancy when CS(2)-exposed after 24 h, deep staining of ATK and pAKT protein in NCG+CS(2) group, the AMPK and pAMPK protein staining became lighter. Conclusion: Dietary supplementation of NCG can interfere with the embryo loss induced by CS(2) by altering the total amount of AKT/AMPK molecules.

Female-biased embryonic death from inflammation induced by genomic instability.

Genomic instability can trigger cellular responses that include checkpoint activation, senescence and inflammation1,2. Although genomic instability has been extensively studied in cell culture and cancer paradigms, little is known about its effect during embryonic development, a period of rapid cellular proliferation. Here we report that mutations in the heterohexameric minichromosome maintenance complex-the DNA replicative helicase comprising MCM2 to MCM73,4-that cause genomic instability render female mouse embryos markedly more susceptible than males to embryonic lethality. This bias was not attributable to X chromosome-inactivation defects, differential replication licensing or X versus Y chromosome size, but rather to 'maleness'-XX embryos could be rescued by transgene-mediated sex reversal or testosterone administration. The ability of exogenous or endogenous testosterone to protect embryos was related to its anti-inflammatory properties5. Ibuprofen, a non-steroidal anti-inflammatory drug, rescued female embryos that contained mutations in not only the Mcm genes but also the Fancm gene; similar to MCM mutants, Fancm mutant embryos have increased levels of genomic instability (measured as the number of cells with micronuclei) from compromised replication fork repair6. In addition, deficiency in the anti-inflammatory IL10 receptor was synthetically lethal with the Mcm4Chaos3 helicase mutant. Our experiments indicate that, during development, DNA damage associated with DNA replication induces inflammation that is preferentially lethal to female embryos, because male embryos are protected by high levels of intrinsic testosterone.

Effect of adoptive transfer of CD4+CD25+Foxp3+ Treg induced by trichostatin A on the prevention of spontaneous abortion.

OBJECTIVE: To investigate whether epigenetic modification of CD4+CD25- T-cells in vitro can make up for the inadequacy of CD4+CD25+Foxp3+ Treg in animal model of spontaneous abortion and prevent immune response-mediated spontaneous abortion. METHODS: Trichostatin A (TSA) was applied to inhibit histone deacetylases (HDACs) and thereby to epigenetically modify the special location of Foxp3 gene in CD4+CD25- T-cells of CBA/J mice. The expressions of CD25, Foxp3, CTLA-4 and PD-1 of CD4+ T cells isolated from spleen of mice were characterized by flow cytometric analysis. Concentrations of transforming growth factor- ß (TGF-ß) and IL-10 in the supernatants of cultured Treg were measured using ELISA. The purified CD4+ T cells treated with different reagents were injected into pregnant CBA/J mice mated with DBA/2J males on Day 1 and 4 of pregnancy, respectively. The embryo resorption rate was assessed on Day 14 of pregnancy. RESULTS: TSA treatment significantly increased the population of CD4+CD25+Foxp3+ iTreg. Those TSA induced Treg expressed high levels of PD-1 and CTLA-4, and secreted high levels of TGF-ß and IL-10. Adoptive transfer of those iTreg at both early stage and implantation of stage of pregnancy significantly increased population of CD4+CD25+Foxp3+ Treg in spleens of recipient miscarriage prone mice and significantly reduced resorption in those mice. CONCLUSION: Epigenetic regulation of Foxp3 can generate functional regulatory T-cells. Adoptive transfer of TSA- induced CD4+CD25+Foxp3+ Treg at an early stage of pregnancy can induce maternal-fetal immune tolerance and reduce embryo resorption in miscarriage prone mice.

Induced endometrial trauma (endometrial scratch) in the mid-luteal menstrual cycle phase preceding first cycle IVF/ICSI versus usual IVF/ICSI therapy: study protocol for a randomised controlled trial.

INTRODUCTION: Endometrial trauma commonly known as endometrial scratch (ES) has been shown to improve pregnancy rates in women with a history of repeated implantation failure undergoing in vitro fertilisation (IVF), with or without intracytoplasmic sperm injection (ICSI). However, the procedure has not yet been fully explored in women having IVF/ICSI for the first time. This study aims to examine the effect of performing an ES in the mid-luteal phase prior to a first-time IVF/ICSI cycle on the chances of achieving a clinical pregnancy and live birth. If ES can influence this success rate, there would be a significant cost saving to the National Health Service through decreasing the number of IVF/ICSI cycles necessary to achieve a pregnancy, increase the practice of single embryo transfer and consequently have a large impact on risks and costs associated with multiple pregnancies. METHODS AND ANALYSIS: This 30-month, UK, multicentre, parallel group, randomised controlled trial includes a 9-month internal pilot and health economic analysis recruiting 1044 women from 16 fertility units. It will follow up participants to identify if IVF/ICSI has been successful and live birth has occurred up to 6 weeks post partum. Primary analysis will be on an intention-to-treat basis. A substudy of endometrial samples obtained during the ES will assess the role of immune factors in embryo implantation. Main trial recruitment commenced on January 2017 and is ongoing.Participants randomised to the intervention group will receive the ES procedure in the mid-luteal phase of the preceding cycle prior to first-time IVF/ICSI treatment versus usual IVF/ICSI treatment in the control group, with 1:1 randomisation. The primary outcome is live birth rate after completed 24 weeks gestation. ETHICS AND DISSEMINATION: South Central-Berkshire Research Ethics Committee approved the protocol. Findings will be submitted to peer-reviewed journals and abstracts to relevant national and international conferences. TRIAL REGISTRATION NUMBER: ISRCTN23800982; Pre-results.

Vitamin D3 pretreatment protects against lipopolysaccharide-induced early embryo loss through its anti-inflammatory effects.

PROBLEM: Increasing evidence demonstrates that inflammatory cytokines are involved in LPS-induced adverse pregnant outcomes including early embryo loss. Vitamin D3 (VitD3) has anti-inflammatory activity. We aimed to investigate the effects of vitamin D3 (VitD3) on LPS-induced early embryo loss in mice. METHOD OF STUDY: All pregnant mice except controls were intraperitoneally (ip) injected with LPS on GD7. In VitD3 alone and LPS+VitD3 groups, pregnant mice were pretreated with VitD3 by gavage daily from GD5 to GD7. RESULTS: LPS caused 62.5% pregnant mice with early embryo loss. Interestingly, the rate of abortion dropped to 14.3% when pregnant mice were pretreated with VitD3. Additional experiment showed that VitD3 significantly attenuated LPS-evoked elevation on TNF-α, IFN-γ, MIP-2, and nitrate plus nitrite in maternal serum. In addition, VitD3 alleviated LPS-induced COX-2 expression in the decidua and attenuated the elevation of PGF2α in maternal serum. Although VitD3 had no effect on IL-10 in maternal serum, it induced further elevation of serum IL-10 level in LPS-treated mice. Further analysis showed that VitD3 activated VDR signaling, simultaneously inhibited LPS-induced nuclear translocation of NF-κB p65 subunits in the decidua. CONCLUSIONS: VitD3 protects mice from LPS-induced early embryo loss at least partially through its anti-inflammatory effects.

Nicotinamide benefits both mothers and pups in two contrasting mouse models of preeclampsia.

Preeclampsia (PE) complicates ∼5% of human pregnancies and is one of the leading causes of pregnancy-related maternal deaths. The only definitive treatment, induced delivery, invariably results in prematurity, and in severe early-onset cases may lead to fetal death. Many currently available antihypertensive drugs are teratogenic and therefore precluded from use. Nonteratogenic antihypertensives help control maternal blood pressure in PE, but results in preventing preterm delivery and correcting fetal growth restriction (FGR) that also occurs in PE have been disappointing. Here we show that dietary nicotinamide, a nonteratogenic amide of vitamin B3, improves the maternal condition, prolongs pregnancies, and prevents FGR in two contrasting mouse models of PE. The first is caused by endotheliosis due to excess levels in the mothers of a soluble form of the receptor for vascular endothelial growth factor (VEGF), which binds to and inactivates VEGF. The second is caused by genetic absence of Ankiryn-repeat-and-SOCS-box-containing-protein 4, a factor that contributes to the differentiation of trophoblast stem cells into the giant trophoblast cells necessary for embryo implantation in mice; its absence leads to impaired placental development. In both models, fetal production of ATP is impaired and FGR is observed. We show here that nicotinamide decreases blood pressure and endotheliosis in the mothers, probably by inhibiting ADP ribosyl cyclase (ADPRC), and prevents FGR, probably by normalizing fetal ATP synthesis via the nucleotide salvage pathway. Because nicotinamide benefits both dams and pups, it merits evaluation for preventing or treating PE in humans.

Embryonic and fetal mortality in river buffalo (Bubalus bubalis).

River buffalo are able to adapt to diverse climatic zones and are widespread globally. The resource use efficiency of buffalo is highly relevant in a resource-constrained world and the increasing requirement to produce more food. Buffalo clearly have an important role in meeting the growing demand for animal protein. In the Mediterranean and higher latitudes, buffalo show annual cycles of ovarian activity, embryonic development, and pregnancy rate. In buffalo, the CL starts to develop early in the cycle, and there is also an early increase in concentrations of progesterone (P4) in circulation. This appears to be necessary for optimal embryonic development. The failure to establish a pregnancy in buffalo can occur before Day 21 (early embryonic mortality), from Day 21 to 45 (late embryonic mortality), and from Day 46 to 90 (fetal mortality) after mating. Treatment with P4, hCG, and GnRH on Day 5 after mating increases P4 in circulation and reduces early embryonic mortality in circumstances where concentrations of P4 are relatively low. The same treatments applied on Day 20 to 25 after mating can lower the occurrence of late embryonic mortality and fetal mortality.

Pregnancy losses in cattle: potential for improvement.

For heifers, beef and moderate-yielding dairy cows, it appears that the fertilisation rate generally lies between 90% and 100%. For high-producing dairy cows, there is a less substantive body of literature, but it would appear that the fertilisation rate is somewhat lower and possibly more variable. In cattle, the major component of embryo loss occurs in the first 16 days following breeding (Day 0), with emerging evidence of greater losses before Day 8 in high-producing dairy cows. In cattle, late embryo mortality causes serious economic losses because it is often recognised too late to rebreed females. Systemic concentrations of progesterone during both the cycle preceding and following insemination affect embryo survival, with evidence of either excessive or insufficient concentrations being negatively associated with survival rate. The application of direct progesterone supplementation or treatments to increase endogenous output of progesterone to increase embryo survival cannot be recommended at this time. Energy balance and dry matter intake during the first 4 weeks after calving are critically important in determining pregnancies per AI when cows are inseminated at 70-100 days after calving. Level of concentrate supplementation of cows at pasture during the breeding period has minimal effects on conception rates, although sudden reductions in dietary intake should be avoided. For all systems of milk production, more balanced breeding strategies with greater emphasis on fertility and feed intake and/or energy must be developed. There is genetic variability within the Holstein breed for fertility traits, which can be exploited. Genomic technology will not only provide scientists with an improved understanding of the underlying biological processes involved in fertilisation and the establishment of pregnancy, but also, in the future, could identify genes responsible for improved embryo survival. Such information could be incorporated into breeding objectives in order to increase the rate of genetic progress for embryo survival. In addition, there is a range of easily adoptable management factors, under producer control, that can either directly increase embryo survival or ameliorate the consequences of low embryo survival rates. The correction of minor deficits in several areas can have a substantial cumulative positive effect on herd reproductive performance.

Macrophage depletion and TNF-α inhibition prevent resorption in CBA/J × DBA/2 model of CpG-induced abortion.

OBJECTIVE: To elucidate the mechanism by which embryo-resorption was enhanced by pathogenic CpG ODN motif in abortion-prone CBA/J × DBA/2 model and to develop a counter strategy for normal pregnancy outcome. METHODS: This is an animal model-based study. Abortion-prone model is established by CBA/J × DBA/2. An infection was mimicked by CpG ODN injection. RESULTS: Embryo-resorption was readily induced by CpG ODN in low doses of CpG ODN (∼25 µg/dam) when intraperitoneally (IP) injected on gestational day(gd) 6.5 in male DBA/2 mated CBA/J female mice. A more modest decline in Progesterone(P4), but not Estrogen(E2) was observed after exposure to CpG ODN in the model. P4 supplement fail to improve pregnancy outcomes, even at pharmocology dose. CpG ODN-induced fetal resorption is prevented by the treatment of anti-F4/80 or by that of anti-TNFα.In the implantation sites, the treatment of anti-F4/80 inhibits the increase both of F4/80(+) macrophage proportion and TNF-αexpression level which are induced by CpG ODN. The anti-TNFαtreatment also recovers CpG ODN-induced reduction of CD4(+)Foxp3(+) T cells. CONCLUSION: Circulating P4 is not responsible for the process by which CpG ODN-induced embryonic resorption in an abortion-prone mice. Macrophage depletion and TNF-α inhibition are really noteworthy for CpG ODN-induced pregnancy disruption.

Progesterone modulates the LPS-induced nitric oxide production by a progesterone-receptor independent mechanism.

Genital tract infections caused by Gram-negative bacteria induce miscarriage and are one of the most common complications of human pregnancy. LPS administration to 7-day pregnant mice induces embryo resorption after 24h, with nitric oxide playing a fundamental role in this process. We have previously shown that progesterone exerts protective effects on the embryo by modulating the inflammatory reaction triggered by LPS. Here we sought to investigate whether the in vivo administration of progesterone modulated the LPS-induced nitric oxide production from peripheral blood mononuclear cells from pregnant and non-pregnant mice. We found that progesterone downregulated LPS-induced nitric oxide production by a progesterone receptor-independent mechanism. Moreover, our results suggest a possible participation of glucocorticoid receptors in at least some of the anti-inflammatory effects of progesterone.

Endometrial injury prior to assisted reproductive techniques for recurrent implantation failure: a systematic literature review.

Endometrial injury to improve implantation for women undergoing assisted reproductive techniques has attracted a lot of attention recently and has rapidly become incorporated into clinical practice. The aim of this study is, thus, to assess the effectiveness and safety of endometrial injury performed in the cycle preceding assisted reproductive techniques in women with recurrent implantation failure. Electronic database searches, including MEDLINE, EMBASE, CENTRAL and grey literature, up to 30th May 2015 were conducted with no restrictions. Randomized controlled trials comparing endometrial injury versus placebo or no treatment in the cycle preceding assisted reproductive techniques in women with recurrent implantation failure were selected. The primary outcome was live birth rate. Secondary outcomes were clinical pregnancy, implantation, miscarriage and procedure-related complication rates. Of the 1115 publications identified, 4 met the inclusion criteria. Meta-analysis was not possible due to significant clinical heterogeneity among the included studies. Patients' characteristics differed, as did the intervention used with endometrial injury being performed at different phases of the preceding menstrual cycle. Moreover, the effect of endometrial injury on live birth and clinical pregnancy rates were inconsistent among the included studies. In summary, there is currently insufficient evidence to support the use of endometrial injury in women with recurrent implantation failure undergoing assisted reproductive techniques while the procedure-associated complication rate has not been assessed. Clinical implementation should, thus, be deferred until robust evidence becomes available.

Peri-ovulatory putrescine supplementation reduces embryo resorption in older mice.

STUDY QUESTION: Does peri-ovulatory putrescine supplementation of older mice improve oocyte quality and reduce the incidence of embryo resorption? SUMMARY ANSWER: Peri-ovulatory putrescine supplementation in older mice improved oocyte quality, as indicated by increased blastocyst cell numbers and reduced the incidence of embryo resorption. WHAT IS KNOWN ALREADY: Rodents exhibit a transient rise of ornithine decarboxylase (ODC) and putrescine in the ovaries during ovulation. Older mice exhibit reduced ovarian ODC activity during ovulation. Supplementation of in vitro maturation medium with putrescine reduces oocyte aneuploidy rates of older mice. STUDY DESIGN, SIZE, DURATION: The rationale was to correct ovarian putrescine deficiency in older mice by peri-ovulatory putrescine supplementation in drinking water and to observe the reproductive consequences of this intervention. This project was conducted between 2010 and 2014. PARTICIPANTS/MATERIALS, SETTING, METHODS: Older mice (9-11 months of age) were given regular drinking water (control) or drinking water with 1% putrescine dihydrochloride (62 mM) for 2-4 days before mating. Plugged mice were then withdrawn from putrescine supplementation. Blastocysts were retrieved on 3.5 days post coitum (dpc) for the determination of cell numbers. For resorption analyses, mice were killed on 9.5 dp or 12.5 dpc, and implantation sites were dissected to determine the embryo status. For birth studies, mice were examined every morning between 16.5 and 23.5 dpc. Births were recorded as live or stillbirth. MAIN RESULTS AND THE ROLE OF CHANCE: We demonstrated that deficiency of ovarian putrescine in older mice can be restored by peri-ovulatory putrescine supplementation in drinking water. Putrescine supplementation in older mice increased blastocyst cell numbers (from 40 to 54; P < 0.0001, t-test), reduced embryo resorption rates (from 41.1 to 15.4% in old C57BL/6 mice, P < 0.0001, Fisher's exact test; from 14.2 to 6.4% in old CF1 mice, P = 0.004, Fisher's exact test), and doubled the number of live born pups. Furthermore, exogenous putrescine exhibited rapid absorption and excretion, and showed no toxicity to mothers or fetuses. LIMITATIONS, REASONS FOR CAUTION: The mechanism of putrescine action in oocytes and/or ovaries remains unclear. WIDER IMPLICATIONS OF THE FINDINGS: Peri-ovulatory putrescine deficiency in older mice appears to adversely impact on oocyte maturation resulting in poor quality embryos (as assessed by blastocyst cell numbers) and early embryo death. This study demonstrates a natural and simple remedy to improve oocyte quality in older women. STUDY FUNDING/COMPETING INTERESTS: This study was supported by the NSERC, the March of Dimes Foundation, and the National Natural Science Foundation of China. The authors declare no competing interest.

Management Strategies Aiming to Improve Horse Welfare Reduce Embryonic Death Rates in Mares.

The objective of this retrospective study was to evaluate the effect of management strategies aiming to improve animal well-being on pregnancy and embryonic death (ED) rates. Breeding records of a cohort of 1206 Thoroughbred mares brought to a stallion station facility, to be bred with the stallions housed there, were evaluated during ten breeding seasons. Mares were blocked according to management strategies in two groups: Stress and Relax. Strategies used to improve animal well-being (Relax group) were as follows: stopping the teasing routine, reducing or eliminating stall confinement, reducing the number of mares per group and maintaining herd stability during the breeding season. In barren mares, the pregnancy rate was higher in the Relax group (91.8%) when compared to the observed in Stress group (84.7%). However, no difference in pregnancy rates were observed (Stress = 85.2% vs. Relax = 86.2) in foaling mares. ED rate was higher in barren and foaling mares of the Stress group mares (25.5% and 26.8%, respectively) compared with the Relax group (16.1% and 14.7%, respectively). No significant differences were observed on foal heat pregnancy rate between groups; yet, the embryo loss on foal heat was significant reduced in Relax mares (Relax = 8.7% vs Stress = 24.5%). In conclusion, management strategies aimed to reduce social stress can reduce early pregnancy losses and the average cycles per pregnancy, improving reproductive performance in mares.

Recurrent pregnancy loss: evaluation and treatment.

Recurrent pregnancy loss (RPL) is a multifactorial condition. Approximately half of patients with RPL will have no explanation for their miscarriages. De novo chromosome abnormalities are common in sporadic and recurrent pregnancy loss. Testing for embryonic abnormalities can provide an explanation for the miscarriage in many cases and prognostic information. Regardless of the cause of RPL, patients should be reassured that the prognosis for live birth with an evidence-based approach is excellent for most patients. The authors review current evidence for the evaluation and treatment of RPL and explore the proposed use of newer technology for patients with RPL.

Knockdown of hypothalamic RFRP3 prevents chronic stress-induced infertility and embryo resorption.

Whereas it is well established that chronic stress induces female reproductive dysfunction, whether stress negatively impacts fertility and fecundity when applied prior to mating and pregnancy has not been explored. In this study, we show that stress that concludes 4 days prior to mating results in persistent and marked reproductive dysfunction, with fewer successful copulation events, fewer pregnancies in those that successfully mated, and increased embryo resorption. Chronic stress exposure led to elevated expression of the hypothalamic inhibitory peptide, RFamide-related peptide-3 (RFRP3), in regularly cycling females. Remarkably, genetic silencing of RFRP3 during stress using an inducible-targeted shRNA completely alleviates stress-induced infertility in female rats, resulting in mating and pregnancy success rates indistinguishable from non-stress controls. We show that chronic stress has long-term effects on pregnancy success, even post-stressor, that are mediated by RFRP3. This points to RFRP3 as a potential clinically relevant single target for stress-induced infertility.