ABCC4 is a PGE2 efflux transporter in the ovarian follicle: A mediator of ovulation and a potential non-hormonal contraceptive target.

The role of prostaglandins (PGs) in the ovulatory process is known. However, the role of the ATP binding cassette subfamily C member 4 (ABCC4), transmembrane PG carrier protein, in ovulation remains unknown. We report herein that ABCC4 expression is significantly upregulated in preovulatory human granulosa cells (GCs). We found that PGE2 efflux in cultured human GCs is mediated by ABCC4 thus regulating its extracellular concentration. The ABCC4 inhibitor probenecid demonstrated effective blocking of ovulation and affects key ovulatory genes in female mice in vivo. We postulate that the reduction in PGE2 efflux caused by the inhibition of ABCC4 activity in GCs decreases the extracellular concentration of PGE2 and its ovulatory effect. Treatment of female mice with low dose of probenecid as well as with the PTGS inhibitor indomethacin or Meloxicam synergistically blocks ovulation. These results support the hypothesis that ABCC4 has an important role in ovulation and might be a potential target for non-hormonal contraception, especially in combination with PGE2 synthesis inhibitors. These findings may fill the gap in understanding the role of ABCC4 in PGE2 signaling, enhance the understanding of ovulatory disorders, and facilitate the treatment and control of fertility.

Sperm Donors' Identity Disclosure: Is It REALLY Crucial? For Whom?

OBJECTIVE: To study the preference of sperm donors with identity disclosure (ID) versus anonymous donors (AD) and to understand if this selection affects clinical outcomes in an Israeli population. METHODS: This retrospective study included patients who chose imported sperm donation during 2017-2021. Of these, 526 used their own (autologous) oocytes and 43 patients used donated oocytes (DO). The primary endpoint was the type of chosen donor with ID versus AD. We examined the tendency toward ID according to demographic parameters and the theoretical impact of donor-type selection on reproductive outcome and compared patients who performed cycles with autologous oocytes with those using DO. RESULTS: Single women had a significantly higher probability of choosing sperm donors with ID than heterosexual couples (55.6% vs. 33.3%, OR 2.5, CI 95% 1.52-4.11, P < 0.001). Although not significant, same-sex couples were more likely to choose sperm donors with ID than heterosexual couples (49.1% vs. 33.3%, OR 1.93, CI 95% 0.97-3.85, P = 0.06). Sperm donor samples, 2501 vials, were imported. It was performed 698 intra-uterine insemination and 812 in vitro fertilization cycles were performed, respectively, resulting in 283 pregnancies without differences between patients who chose sperm donors with ID versus AD sperm. No significant differences were observed regarding the option for sperm donors with ID between patients using DO (44.2%) and those using autologous oocytes (51.3%). CONCLUSION: While ID is important for a certain section (mainly single) of recipients, it is far from the only dominant factor during donor selection. Sperm donation type does not impact clinical outcomes.

Cryopreserved testicular spermatozoa among patients with azoospermia.

PURPOSE: To investigate cryopreserved testicular spermatozoa among patients with azoospermia. METHODS: In this retrospective study spanning from October 1993 to December 2021, we examined men diagnosed with azoospermia who underwent testicular spermatozoa cryopreservation. Data from medical records included utilization and disposal of sperm samples, age at initial cryopreservation. We analyzed the data over 20 years using Kaplan-Meier curves, compared age with the log-rank test, and assessed hazard ratios (HR) with 95% confidence intervals (CI) using Cox regression analysis. RESULTS: A total of 356 patients with a mean age of 32.1 ± 6 were included. Of these, 225 patients utilized thawed testicular sperm for fertility treatments, with 118 patients using all their frozen straws and 107 patients partially using their stored straws. Additionally, 29 patients opted for disposal (six patients partially used their testicular spermatozoa before disposal), resulting in 108 patients who neither used nor disposed of their straws. From a laboratory standpoint, nearly 90% of patients contributed a single testicular sample, which was subsequently divided and cryopreserved as straws, with a median of 4 straws per sample. Notably, in the older age group (> 35 years old), there were a significantly lower usage rate and a higher disposal rate compared to the younger age groups (p < 0.05 for both), corroborated by univariable Cox analysis. CONCLUSIONS: This extensive study unveils unique patterns in the preservation and disposal of testicular spermatozoa among azoospermic patients. Most patients utilize a significant portion of their stored samples, while older patients tend to use their testicular spermatozoa less frequently.

[THE EFFECT OF ETHNICITY ON THE AGE OF SINGLE PATIENTS APPLYING FOR SPERM DONATION].

INTRODUCTION: Sperm banks have shifted from assisting heterosexual couples with male infertility to primarily serving single women and female couples through medical services, reflecting advances in fertility treatments and societal changes. AIMS: Evaluate demographic changes among single women who have applied for sperm donation during 30 years in the State of Israel. METHODS: This retrospective cohort study includes 4265 single women who received sperm donation between January 1992 and December 2021, at a tertiary medical center. We divided the follow-up period into 6 groups of 5 years each. A comparison was made of the demographic characteristics of single women applying for sperm donation in different periods according to: 1) age at the beginning of the treatment; 2) ethnic origin - 7 ethnic groups. RESULTS: The average age of single women who received sperm donation was 38.2±4.4 years. The average age of patients decreased from 39.58 years in 1997-1992 to 38.08 years in 2017-2021 (p-value<0.05). Ashkenazic Jews (38.4%) and Sephardic Jews (37.7%) were the most common ethnic origins among single women, with Arab women comprising only 0.2%. Single Jewish women of Ashkenazi descent seek sperm donation treatment almost a year earlier than their Sephardic counterparts (Arab countries and North Africa). CONCLUSIONS: Single Israeli women opting for early sperm donation carries significant clinical, social, and economic implications. Women from conservative social backgrounds appear to be less inclined to seek sperm donation as single individuals or tend to delay this option until a later age, in contrast to women from liberal backgrounds.

Treatment safety of ART cycles with extremely high oestradiol concentrations using GnRH agonist trigger.

RESEARCH QUESTION: Are IVF treatments with extremely high peak oestradiol levels and gonadotrophin releasing hormone (GnRH) agonist trigger associated with higher complication rates? DESIGN: A retrospective cohort study including patients from two large medical centres treated between 2019 and 2021. A study group with extremely high peak oestradiol levels (≥20,000 pmol/l on the day of ovarian stimulation, or ≥15,000 pmol/l on the previous day) and a control group with normal range oestradiol levels (3000-12000 pmol/l) that received GnRH agonist triggering. Patients were surveyed about complaints and medical care related to ovum retrieval and medical files were reviewed. Major complication rates and the need for medical assistance were compared. RESULTS: Several differences between the study and control group were observed because of the study design: mean age was 33.01 ± 5.14 versus 34.57 ± 4.52 (P < 0.001), mean peak oestradiol levels was 26645.34 ± 8592.57 pmol/l versus 7229.75 ± 2329.20 pmol/l (P < 0.001), and mean number of oocytes were 27.55 ± 13.46 versus 11.67 ± 5.76 (P < 0.001) for the study and control group, respectively. Major complications and hospitalization rates were similar between the study and control groups (three [1.25%] versus one [0.48%]; P = 0.62 and three [1.25%] versus two [0.96%]; P = 1.0, respectively). Thirty-six patients (15.1%) in the study group and 11 (5.3%) in the control group sought medical care after retrieval, mostly due to abdominal pain, without the need for further workup or hospitalization (P < 0.001). CONCLUSIONS: Extremely high oestradiol levels were not associated with thromboembolic events, higher major complication or hospitalization rates, and therefore may be considered safe. Nevertheless, patients may be informed of possible higher rates of discomfort, mostly abdominal pain. Larger studies are warranted to confirm our results.

Critical Demographic Changes among Sperm Donation Recipients Over Three Decades.

BACKGROUND: Sperm banks initially focused on providing sperm donation (SD) to heterosexual couples grappling with severe male infertility. Notable advancements in fertility treatments and sociological trends have broadened the scope of SD toward single women and same sex female couples. OBJECTIVES: To evaluate SD recipient characteristics over the last three decades in Israel according to demographic parameters. METHODS: This retrospective cohort study included 5489 women who received SD between January 1992 and December 2021 from a tertiary referral center. We divided the overall period into six groups of five years each. A comparison of demographic characteristics of women who received SD in different periods was performed according to age at the beginning of the treatment, marital status (single women and same sex female couples, heterosexual couples), and ethnic origin. RESULTS: The average age of women who received SD was 37.02 ± 5.36 years. The average patient age rose from 35.08 years in 1992-1997 to 37.43 years in 2017-2021 (P-value < 0.01). The use of SD was more common among single women and same sex female couples compared to heterosexual couples in later years. Regarding single and same sex female couple, the percentage of SD recipients increased radically from 33% to 88.1% (P-value < 0.01). CONCLUSIONS: Modern sperm banks treat older patients in non-heterosexual relationships. These trends encompass not only medical implications (e.g., in vitro fertilization vs. intrauterine insemination) but also delve into the personal and sociological impact experienced by both patients and offspring.

IVF under COVID-19: treatment outcomes of fresh ART cycles.

STUDY QUESTION: Does prior severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in women undergoing fertility treatments affect the outcomes of fresh ART cycles? SUMMARY ANSWER: SARS-CoV-2 infection does not affect fresh ART treatment outcomes, except for a possible long-term negative effect on oocyte yield (>180 days postinfection). WHAT IS KNOWN ALREADY: A single previous study suggested no evidence that a history of asymptomatic or mild SARS-CoV-2 infection in females caused impairment of fresh ART treatment outcomes. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study, including all SARS-CoV-2 infected women who underwent fresh ART cycles within a year from infection (the first cycle postinfection), between October 2020 and June 2021, matched to non-diagnosed controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients from two large IVF units in Israel who were infected with SARS-CoV-2 and later underwent fresh ART cycles were matched by age to non-diagnosed, non-vaccinated controls. Demographics, cycle characteristics and cycle outcomes, including oocyte yield, maturation rate, fertilization rate, number of frozen embryos per cycle and clinical pregnancy rates, were compared between groups. MAIN RESULTS AND THE ROLE OF CHANCE: One hundred and twenty-one infected patients and 121 controls who underwent fresh ART cycles were included. Oocyte yield (12.50 versus 11.29; P = 0.169) and mature oocyte rate (78% versus 82%; P = 0.144) in all fresh cycles were similar between groups, as were fertilization rates, number of frozen embryos per cycle and clinical pregnancy rates (43% versus 40%; P = 0.737) in fresh cycles with an embryo transfer. In a logistic regression model, SARS-CoV-2 infection more than 180 days prior to retrieval had a negative effect on oocyte yield (P = 0.018, Slope = -4.08, 95% CI -7.41 to -0.75), although the sample size was small. LIMITATIONS, REASONS FOR CAUTION: A retrospective study with data that was not uniformly generated under a study protocol, no antibody testing for the control group. WIDER IMPLICATIONS OF THE FINDINGS: The study findings suggest that SARS-CoV-2 infection does not affect treatment outcomes, including oocyte yield, fertilization and maturation rate, number of good quality embryos and clinical pregnancy rates, in fresh ART cycles, except for a possible long-term negative effect on oocyte yield when retrieval occurs >180 days post-SARS-CoV-2 infection. Further studies are warranted to support these findings. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: 0010-21-HMC, 0094-21-ASF.

What can we learn about posthumous sperm retrieval after extra long-term follow-up?

PURPOSE: To describe spermatozoa extraction rate by testicular sperm extraction (TESE) for posthumous sperm retrieval (PMSR) and examine harvest time impact on sperm motility; to compare long-term sperm usage between married vs. single deceased men. METHODS: This retrospective study included all PMSR cases in Shamir Medical Center during 2003-2021. We evaluated sperm cryopreservation according to latency time after death. Then, we assessed sperm usage according to Israeli PMSR regulations. RESULTS: The study included 69 (35 married and 34 singles) deceased men with average age of 30.3 ± 7.8 years. Sperm was cryopreserved in 65 cases (94.2%) after maximum and average harvest time of 40 and 16.5 ± 8.1 h, respectively. Motile sperm extraction was associated with significantly shorter harvest time compared with non-motile sperm (13.8 ± 7.3 vs. 18.7 ± 8.1 h, p = 0.046). Sperm usage among married deceased was significantly higher than single (15.6% vs. 0%, p = 0.05). Disposal requests were lower among single compared to married men relatives without reaching statistical difference. Eventually, single men had significantly higher rate of non-used cryopreserved samples (93.8% vs 69.6%, p = 0.01). CONCLUSION: This large long-term cohort study demonstrates high efficacy of PMSR. We found significant harvest latency time difference between motile and non-motile preserved sperm. Clinical sperm usage rate justifies the efforts for PMSR among married deceased. However, contradicting policy on the topic of single men (which implies liberal sperm preservation but rigid prevention of usage) results with high non-used sperm rate and relatives' extremely sophisticated emotional burden.

The impact of past COVID-19 infection on pregnancy rates in frozen embryo transfer cycles.

PURPOSE: To study the effect of SARS-CoV-2 infection on pregnancy rates in frozen embryo transfer (FET) cycles. METHODS: A retrospective cohort study including women under the age of 42 with documented SARS-CoV-2 infection up to 1 year prior to treatment, undergoing FET cycles in the first half of 2021, with transfer of embryos generated prior to the infection. Controls were SARS-CoV-2 non-diagnosed, non-vaccinated women matched by age, number, and day of embryo transfer. Demographic and cycle characteristics and outcomes were compared. RESULTS: Forty-one recovered women and 41 controls were included. Pregnancy rates were 29% and 49% respectively (p = 0.070). Stratification by time from SARS-CoV-2 infection to transfer into ≤ 60 and > 60 days revealed a difference in pregnancy rates, with women in the COVID group having lower pregnancy rates if infected in proximity to the transfer (21% vs. 55%; p = 0.006). In a logistic regression model, infection was a significant variable (p = 0.05, OR 0.325, 95% CI 0.106-0.998). Logistic regression applied on the subgroup of women infected in proximity to the transfer further strengthened the univariate results, with COVID-19 remaining a significant parameter (p = 0.005, OR 0.072, 95% CI 0.012-0.450). CONCLUSIONS: In FET cycles of patients with past SARS-CoV-2 infection, in which oocytes were retrieved prior to infection, decreased pregnancy rates were observed, specifically in patients who recovered less than 60 days prior to embryo transfer. Pending further studies, in cases of FET cycles with limited number of embryos, postponing embryo transfer for at least 60 days following recovery from COVID-19 might be considered when feasible.

Endometrial compaction is associated with increased clinical and ongoing pregnancy rates in unstimulated natural cycle frozen embryo transfers: a prospective cohort study.

PURPOSE: To investigate the association between endometrial compaction and pregnancy rates in unstimulated natural cycle frozen embryo transfers. DESIGN: A single-center prospective cohort study. Endometrial thickness by transvaginal ultrasound and blood progesterone levels on the day of ovulation and the day of embryo transfer were evaluated in patients undergoing natural cycle frozen embryo transfer. Compaction was defined as > 5% decrease in endometrial thickness between ovulation day and day of transfer. Clinical and ongoing pregnancy rates in cycles with and without compaction were compared. RESULTS: Seventy-one women were included, of which 44% had endometrial compaction, with similar rates when subdividing the patients by day of transfer (day 3 or day 5). Clinical and ongoing pregnancy rates were higher in the compaction group compared to the non-compaction group (0.58 vs. 0.16, P < 0.001; 0.52 vs. 0.13, P < 0.001 respectively). Subdividing by degree of compaction > 10% and > 15% revealed similar pregnancy rates as > 5%, with no added benefit to higher degrees of compaction. CONCLUSIONS: About half the patients in our study undergoing unstimulated natural cycle frozen embryo transfer experienced compaction of the endometrium, occurring as early as day 3 post-ovulation. This was significantly correlated with increased clinical and ongoing pregnancy rates.

An impressive capacity for cold tolerance plasticity protects against ionoregulatory collapse in the disease vector Aedes aegypti.

The mosquito Aedes aegypti is largely confined to tropical and subtropical regions, but its range has recently been spreading to colder climates. As insect biogeography is tied to environmental temperature, understanding the limits of A. aegypti thermal tolerance and their capacity for phenotypic plasticity is important in predicting the spread of this species. In this study, we report on the chill coma onset (CCO) and recovery time (CCRT), as well as low-temperature survival phenotypes of larvae and adults of A. aegypti that developed or were acclimated to 15°C (cold) or 25°C (warm). Cold acclimation did not affect CCO temperatures of larvae but substantially reduced CCO in adults. Temperature and the duration of exposure both affected CCRT, and cold acclimation strongly mitigated these effects and increased rates of survival following prolonged chilling. Female adults were far less likely to take a blood meal when cold acclimated, and exposing females to blood (without feeding) attenuated some of the beneficial effects of cold acclimation on CCRT. Lastly, larvae suffered from haemolymph hyperkalaemia when chilled, but cold acclimation attenuated the imbalance. Our results demonstrate that A. aegypti larvae and adults have the capacity to acclimate to low temperatures, and do so at least in part by better maintaining ion balance in the cold. This ability for cold acclimation may facilitate the spread of this species to higher latitudes, particularly in an era of climate change.

Functional plasticity of the gut and the Malpighian tubules underlies cold acclimation and mitigates cold-induced hyperkalemia in Drosophila melanogaster.

At low temperatures, Drosophila, like most insects, lose the ability to regulate ion and water balance across the gut epithelia, which can lead to a lethal increase of [K+] in the hemolymph (hyperkalemia). Cold acclimation, the physiological response to a prior low temperature exposure, can mitigate or entirely prevent these ion imbalances, but the physiological mechanisms that facilitate this process are not well understood. Here, we test whether plasticity in the ionoregulatory physiology of the gut and Malpighian tubules of Drosophila may aid in preserving ion homeostasis in the cold. Upon adult emergence, D. melanogaster females were subjected to 7 days at warm (25°C) or cold (10°C) acclimation conditions. The cold-acclimated flies had a lower critical thermal minimum (CTmin), recovered from chill coma more quickly, and better maintained hemolymph K+ balance in the cold. The improvements in chill tolerance coincided with increased Malpighian tubule fluid secretion and better maintenance of K+ secretion rates in the cold, as well as reduced rectal K+ reabsorption in cold-acclimated flies. To test whether modulation of ion-motive ATPases, the main drivers of epithelial transport in the alimentary canal, mediate these changes, we measured the activities of Na+/K+-ATPase and V-type H+-ATPase at the Malpighian tubules, midgut, and hindgut. Na+/K+-ATPase and V-type H+-ATPase activities were lower in the midgut and the Malpighian tubules of cold-acclimated flies, but unchanged in the hindgut of cold-acclimated flies, and were not predictive of the observed alterations in K+ transport. Our results suggest that modification of Malpighian tubule and gut ion and water transport probably prevents cold-induced hyperkalemia in cold-acclimated flies, and that this process is not directly related to the activities of the main drivers of ion transport in these organs, Na+/K+- and V-type H+-ATPases.

Anti-diuretic activity of a CAPA neuropeptide can compromise Drosophila chill tolerance.

For insects, chilling injuries that occur in the absence of freezing are often related to a systemic loss of ion and water balance that leads to extracellular hyperkalemia, cell depolarization and the triggering of apoptotic signalling cascades. The ability of insect ionoregulatory organs (e.g. the Malpighian tubules) to maintain ion balance in the cold has been linked to improved chill tolerance, and many neuroendocrine factors are known to influence ion transport rates of these organs. Injection of micromolar doses of CAPA (an insect neuropeptide) have been previously demonstrated to improve Drosophila cold tolerance, but the mechanisms through which it impacts chill tolerance are unclear, and low doses of CAPA have been previously demonstrated to cause anti-diuresis in insects, including dipterans. Here, we provide evidence that low (femtomolar) and high (micromolar) doses of CAPA impair and improve chill tolerance, respectively, via two different effects on Malpighian tubule ion and water transport. While low doses of CAPA are anti-diuretic, reduce tubule K+ clearance rates and reduce chill tolerance, high doses facilitate K+ clearance from the haemolymph and increase chill tolerance. By quantifying CAPA peptide levels in the central nervous system, we estimated the maximum achievable hormonal titres of CAPA and found further evidence that CAPA may function as an anti-diuretic hormone in Drosophila melanogaster We provide the first evidence of a neuropeptide that can negatively affect cold tolerance in an insect and further evidence of CAPA functioning as an anti-diuretic peptide in this ubiquitous insect model.

The effect of cold acclimation on active ion transport in cricket ionoregulatory tissues.

Cold-acclimated insects defend ion and water transport function during cold exposure. We hypothesized that this is achieved via enhanced active transport. The Malpighian tubules and rectum are likely targets for such transport modifications, and recent transcriptomic studies indicate shifts in Na+-K+ ATPase (NKA) and V-ATPase expression in these tissues following cold acclimation. Here we quantify the effect of cold acclimation (one week at 12°C) on active transport in the ionoregulatory organs of adult Gryllus pennsylvanicus field crickets. We compared primary urine production of warm- and cold-acclimated crickets in excised Malpighian tubules via Ramsay assay at a range of temperatures between 4 and 25°C. We then compared NKA and V-ATPase activities in Malpighian tubule and rectal homogenates from warm- and cold-acclimated crickets via NADH-linked photometric assays. Malpighian tubules of cold-acclimated crickets excreted fluid at lower rates at all temperatures compared to warm-acclimated crickets. This reduction in Malpighian tubule excretion rates may be attributed to increased NKA activity that we observed for cold-acclimated crickets, but V-ATPase activity was unchanged. Cold acclimation had no effect on rectal NKA activity at either 21°C or 6°C, and did not modify rectal V-ATPase activity. Our results suggest that an overall reduction, rather than enhancement of active transport in the Malpighian tubules allows crickets to maintain hemolymph water balance during cold exposure, and increased Malpighian tubule NKA activity may help to defend and/or re-establish ion homeostasis.

Comparison of effects of thawing entire donor sperm vial vs. partial thawing (shaving) on sperm quality.

PURPOSE: Partial thawing of a vial of cryopreserved sperm (shaving) is sometimes applied as a measure to preserve sperm for further use, particularly in cases of very restricted sperm quantity. However, mechanical violence may disrupt the sperm-wall and lead to impaired in-vitro fertilization (IVF) outcomes. MATERIAL AND METHODS: In a retrospective case-control study at a tertiary, university-affiliated medical center, we compared the IVF/intracytoplasmic sperm injection (ICSI) outcomes of patients who used donor sperm following partial thawing (shaving) of the vial of cryopreserved sperm (n = 99) to a control group consisting of patients for whom the vial of sperm was completely thawed before use (n = 99). RESULTS: While no differences were observed in the rates of oocyte fertilization, the mean number of top-quality embryos (TQE) was significantly lower in the shaving group than in the complete thawing group (1.33 ± 0.17 vs. 1.87 ± 0.17, p < 0.02). Experimental analysis of aliquots from the same donors revealed significantly reduced motility in sperm samples that were shaved vs. fully thawed (6.5 vs. 37.1%, p < 0.001). CONCLUSIONS: In cases in which available cryopreserved sperm samples are limited, shaving of the vial without thawing can be used but with caution and only when absolutely necessary. Further, large prospective studies are needed to better clarify whether there is post-thawing sperm damage and to compare IVF outcomes after these two thawing methods.

Outcome of immature oocytes collection of 119 cancer patients during ovarian tissue harvesting for fertility preservation.

PURPOSE: Few clinical options for fertility preservation are available to females with cancer, and data about clinical outcomes is limited. Potential supplementary approaches to fertility preservation include retrieval of immature oocytes followed by in vitro maturation (IVM) and storage. The aim of this study was to evaluate post-thawing outcomes of immature oocytes collected both by transvaginal aspiration and from excised ovarian tissue. METHODS: We conducted a retrospective cohort study of patients treated in a single tertiary center. We reviewed the records of 119 cancer patients who underwent ovarian tissue cryopreservation and immature oocyte harvesting for fertility preservation. All embryos and oocytes that were frozen and thawed were included in the study. Post-thawing outcomes were evaluated. RESULTS: Thirty-five stored embryos from eight patients were thawed. Twenty-nine embryos survived (82% survival rate) and were transferred. Six oocytes were thawed, two oocytes survived, and no oocytes were fertilized. Only one PCOS patient became pregnant, resulting in the normal delivery of a healthy baby. CONCLUSIONS: Although a relatively high number of mature oocytes and embryos can be stored with the combined procedure, the limited rate of pregnancies represents a poor reproductive outcome. Therefore, this approach should be reserved for special groups with limited options.

A mosquito entomoglyceroporin, Aedes aegypti AQP5, participates in water transport across the Malpighian tubules of larvae.

The mosquito Aedes aegypti is the primary vector for arboviral diseases such as Zika fever, dengue fever, chikungunya and yellow fever. The larvae reside in hypo-osmotic freshwater habitats, where they face dilution of their body fluids from osmotic influx of water. The Malpighian tubules help maintain ionic and osmotic homeostasis by removing excess water from the hemolymph; however, the transcellular pathway for this movement remains unresolved. Aquaporins are transmembrane channels thought to permit transcellular transport of water from the hemolymph into the Malpighian tubule lumen. Immunolocalization of A.aegypti aquaporin 5 (AaAQP5) revealed expression by Malpighian tubule principal cells of the larvae, with localization to both the apical and basolateral membranes. Knockdown of AaAQP5 with double-stranded RNA decreased larval survival, reduced rates of fluid, K+ and Na+ secretion by the Malpighian tubules, and reduced Cl- concentrations in the hemolymph. These findings indicate that AaAQP5 participates in transcellular water transport across the Malpighian tubules of larval Aaegypti where global AaAQP5 expression is important for larval survival.

Does BPA alter steroid hormone synthesis in human granulosa cells in vitro?

STUDY QUESTION: Does Bisphenol A (BPA) impair steroid hormone production in human luteinized granulosa cells in vitro? SUMMARY ANSWER: At supra-physiological concentrations, BPA alters progesterone and estradiol synthesis in vitro and significantly reduces the mRNA and protein expression levels of three genes encoding steroidogenesis enzymes. WHAT IS KNOWN ALREADY: In IVF patients, the effects of BPA exposure on cycle outcome are controversial. Previous animal studies have shown that granulosa cell steroid hormone synthesis is compromised after BPA exposure, but their findings have been difficult to replicate in humans due, in part, to the low availability of discarded biological material. STUDY DESIGN, SIZE, DURATION: Luteinized granulosa cells obtained from 44 fertile and infertile patients undergoing in vitro fertilization were cultured for 48 h with different concentrations of BPA (0, 0.2, 0.02, 2.0, 20 µg/ml). PARTICIPANTS/MATERIALS, SETTING, METHODS: Culture medium and total RNA extracted from the luteinized granulosa cells were examined for estradiol and progesterone levels as well as mRNA and protein expression of steroidogenesis enzymes, using enzyme immunoassays, real-time PCR and western blots. MAIN RESULTS AND THE ROLE OF CHANCE: Treatment of granulosa cells with 2 or 20 µg/ml BPA for 48 h resulted in significantly lower progesterone biosynthesis (P < 0.005 and <0.001, respectively). Estradiol production was significantly altered only after incubation with 20 µg/ml of BPA (P < 0.001). These concentrations also significantly reduced the mRNA levels of 3ß-hydroxysteroid dehydrogenase (3ß-HSD), CYP11A1 and CYP19A1 without affecting StAR and 17ß-hydroxysteroid dehydrogenase mRNA expression. Similarly, 3ß-HSD, CYP11A1 and CYP19A1 protein levels were reduced after administration of 20 µg/ml BPA. Lower BPA concentrations similar to, and up to 100 times, the concentrations measured in human follicular fluid, serum and urine did not alter steroidogenesis in primary granulosa cell cultures. LIMITATIONS, REASONS FOR CAUTION: This was an in vitro study investigating the effects of acute exposure (48 h) of BPA on discarded material. As such, the model may not accurately reflect the effect of BPA on the physiological events of follicular steroid hormone synthesis in vivo. WIDER IMPLICATIONS OF THE FINDINGS: Our results show that in vitro exposure to BPA at low doses does not affect granulosa cells steroidogenesis. Combined with recent in vivo studies, these data can be reassuring but further studies are needed to assess the effects of chronic exposure to BPA on ovarian steroidogenesis. STUDY FUNDING AND COMPETING INTERESTS: This study was supported by grant number 1936/12 from the Israeli Science Foundation (ISF). The authors have no conflict of interest.

The 'immunologic theory' of preeclampsia revisited: a lesson from donor oocyte gestations.

OBJECTIVE: To determine the prevalence of placental complications in patients conceived through donor versus autologous oocytes. STUDY DESIGN: A retrospective cohort study including 2 groups of patients who conceived through in vitro fertilization using: (1) donor oocyte (n = 139) and (2) autologous oocyte (n = 126). Only singleton gestations were included. The rate of placental complications including preeclampsia, gestational hypertension, and intrauterine growth restriction was compared between these 2 groups. RESULTS: The women who conceived using donor oocytes were older compared with women who conceived using autologous oocytes (median maternal age 45 vs 41, P < .01). The rate of hypertensive diseases of pregnancy including gestational hypertension and preeclampsia was significantly higher in ovum donor recipients compared with women conceived with autologous oocytes (25% vs 10%, P < .01). Similarly, the rate of intrauterine growth restriction was also higher among patients conceived through oocyte donation although it did not reach statistical significance (9.3% vs 4%, P = .08). When maternal age was restricted to ≤45 years, the rate of hypertensive diseases of pregnancy remained significantly higher among ovum donor compared with autologous oocyte recipients (22% vs 10%, P = .02). Adjustment for maternal age, gravidity, parity, and chronic hypertension revealed that oocyte donation was independently associated with higher rate of hypertensive diseases of pregnancy (P = .01). CONCLUSION: Patients conceived through oocyte donation have an increased risk for placental complications of pregnancy. These findings support the 'immunologic theory' suggesting that immunologic intolerance between the mother and the fetus may play an important role in the pathogenesis of preeclampsia.

Comparison between two protocols for thawed embryo transfer: natural cycle versus exogenous hormone replacement.

INTRODUCTION: There are two most popular protocols for Frozen Embryo Transfer: the natural and the E2&P4 replacement cycles. There is still a controversy whether one is superior over the other. PURPOSE: To compare the outcome in patient groups undergoing FET following these protocols. METHODS: About 1235 FET cycles were retrospectively analyzed during a period of 12 years. In 798 cycles (group A), the natural cycle protocol was used, and in 437 cycles (group B), the exogenous E2&P4 administration protocol was used. RESULTS: The average patient age was 32.11 ± 0.27 years in group A and 32.94 ± 0.19 years in group B (p<0.05). The endometrial thickness was 9.54 ± 0.11 mm and 8.95 ± 0.13 mm in groups A and B, respectively (p<0.001). The peak serum E2 level was 162.51 ± 8.97 pg/mL and 250.78 ± 33.67 pg/mL in groups A and B, respectively (p<0.001). The implantation, clinical pregnancy, and ongoing pregnancy rates in groups A and B were 6.47%, 12.91%, and 10.4% versus 4.26%, 8.47%, and 5.95%, respectively (p<0.05). CONCLUSIONS: Natural endometrial preparation yields better outcome in compare with exogenous E2&P4 in FET cycles with higher endometrial thickness, implantation, and clinical pregnancy rates.