Relaxin in human pregnancy

Seleno-relaxin analogues: effect of internal and external diselenide bonds on the foldability and a fibrosis-related factor of endometriotic stromal cells

Human relaxin-2 (H2 relaxin) is a peptide hormone of about 6 kDa, first identified as a reproductive hormone involved in vasoregulation during pregnancy. It has recently attracted strong interest because of its diverse functions, including anti-inflammatory, anti-fibrotic, and vasodilatory, and has been suggested as a potential peptide-based drug candidate for a variety of diseases. Mature H2 relaxin is constituted by the A- and B-chains stabilized by two interchain disulfide (SS) bridges and one intrachain SS linkage. In this study, seleno-relaxins, SeRlx-α and SeRlx-β, which are [C11UA,C11UB] and [C10UA,C15UA] variants of H2 relaxin, respectively, were synthesized via a one-pot oxidative chain assembly (folding) from the component A- and B-chains. The substitution of SS bonds in a protein with their analogue, diselenide (SeSe) bonds, has been shown to alter the physical, chemical, and physiological properties of the protein. The surface SeSe bond (U11A-U11B) enhanced the yield of chain assembly while the internal SeSe bond (U10A-U15A) improved the reaction rate of the folding, indicating that these bridges play a major role in controlling the thermodynamics and kinetics, respectively, of the folding mechanism. Furthermore, SeRlx-α and SeRlx-β effectively reduced the expression of a tissue fibrosis-related factor in human endometriotic stromal cells. Thus, the findings of this study indicate that the S-to-Se substitution strategy not only enhances the foldability of relaxin, but also provides new guidance for the development of novel relaxin formulations for endometriosis treatment.

R2R01: A long-acting single-chain peptide agonist of RXFP1 for renal and cardiovascular diseases

BACKGROUND

The therapeutic potential of relaxin for heart failure and renal disease in clinical trials is hampered by the short half-life of serelaxin. Optimization of fatty acid-acetylated single-chain peptide analogues of relaxin culminated in the design and synthesis of R2R01, a potent and selective RXFP1 agonist with subcutaneous bioavailability and extended half-life.

EXPERIMENTAL APPROACH

Cellular assays and pharmacological models of RXFP1 activation were used to validate the potency and selectivity of R2R01. Increased renal blood flow was used as a translational marker of R2R01 activity. Human mastocytes (LAD2 cells) were used to study potential pseudo-allergic reactions and CD4+ T-cells to study immunogenicity. The pharmacokinetics of R2R01 were characterized in rats and minipigs.

KEY RESULTS

In vitro, R2R01 had comparable potency and efficacy to relaxin as an agonist for human RXFP1. In vivo, subcutaneous administration of R2R01 increased heart rate and renal blood flow in normotensive and hypertensive rat and did not show evidence of tachyphylaxis. R2R01 also increased nipple length in rats, used as a chronic model of RXFP1 engagement. Pharmacokinetic studies showed that R2R01 has a significantly extended terminal half-life. The in vitro assays with LAD2 cells and CD4+ T-cells showed that R2R01 had low potential for pseudo-allergic and immunogenic reactions, respectively.

CONCLUSION AND IMPLICATIONS

R2R01 is a potent RXFP1 agonist with an extended half-life that increases renal blood flow in various settings including normotensive and hypertensive conditions. The preclinical efficacy and safety data supported clinical development of R2R01 as a potential new therapy for renal and cardiovascular diseases.

The Menstrual Health Manager (MHM): A Resource to Reduce Discrepancies Between Science and Practice in Sport and Exercise

Inadequate research on female health and performance; the complexity of the research; low menstrual health literacy of athletes, coaches, and support staff; and ethical and cultural sensitivities are all recognized as barriers to effective health monitoring for females in sports. Frameworks have been developed for academics to follow to help improve the quality of female-specific research. However, a similar resource that enables correct terminology, and use of health monitoring techniques has not been provided for sporting organizations, coaches, support staff or athletes. Therefore, this critical commentary presents a new resource, the Menstrual Health Manager. This resource may be used to determine the level of menstrual health monitoring detail that may be used by organisations, coaches or athletes, and specifies what reproductive health details the data will provide. This resource aims to provide organizations and coaches with a means of understanding the data that inform their decisions for female athletes. Utilization of this resource may aid in the consistent use of terminology and methods for female-specific health monitoring in both sports and research.

Placental IGFBP1 levels during early pregnancy and the risk of insulin resistance and gestational diabetes

Reduced insulin sensitivity (insulin resistance) is a hallmark of normal physiology in late pregnancy and also underlies gestational diabetes mellitus (GDM). We conducted transcriptomic profiling of 434 human placentas and identified a positive association between insulin-like growth factor binding protein 1 gene (IGFBP1) expression in the placenta and insulin sensitivity at ~26 weeks gestation. Circulating IGFBP1 protein levels rose over the course of pregnancy and declined postpartum, which, together with high gene expression levels in our placenta samples, suggests a placental or decidual source. Higher circulating IGFBP1 levels were associated with greater insulin sensitivity (lesser insulin resistance) at ~26 weeks gestation in the same cohort and in two additional pregnancy cohorts. In addition, low circulating IGFBP1 levels in early pregnancy predicted subsequent GDM diagnosis in two cohorts of pregnant women. These results implicate IGFBP1 in the glycemic physiology of pregnancy and suggest a role for placental IGFBP1 deficiency in GDM pathogenesis.

Human recombinant relaxin-2 (serelaxin) regulates the proteome, lipidome, lipid metabolism and inflammatory profile of rat visceral adipose tissue

Recombinant human relaxin-2 (serelaxin) has been widely proven as a novel drug with myriad effects at different cardiovascular levels, which support its potential therapeutic efficacy in several cardiovascular diseases (CVD). Considering these effects, together with the influence of relaxin-2 on adipocyte physiology and adipokine secretion, and the connection between visceral adipose tissue (VAT) dysfunction and the development of CVD, we could hypothesize that relaxin-2 may regulate VAT metabolism. Our objective was to evaluate the impact of a 2-week serelaxin treatment on the proteome and lipidome of VAT from Sprague-Dawley rats. We found that serelaxin increased 1 polyunsaturated fatty acid and 6 lysophosphatidylcholines and decreased 4 triglycerides in VAT employing ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) based platforms, and that regulates 47 phosphoproteins using SWATH/MS analysis. Through RT-PCR, we found that serelaxin treatment also caused an effect on VAT lipolysis through an increase in the mRNA expression of hormone-sensitive lipase (HSL) and a decrease in the expression of adipose triglyceride lipase (ATGL), together with a reduction in the VAT expression of the fatty acid transporter cluster of differentiation 36 (Cd36). Serelaxin also caused an anti-inflammatory effect in VAT by the decrease in the mRNA expression of tumor necrosis factor α (TNFα), interleukin-1β (IL-1β), chemerin, and its receptor. In conclusion, our results highlight the regulatory role of serelaxin in the VAT proteome and lipidome, lipolytic function, and inflammatory profile, suggesting the implication of several mechanisms supporting the potential benefit of serelaxin for the prevention of obesity and metabolic disorders.

Bioinformatics analysis of a disease-specific lncRNA-miRNA-mRNA regulatory network in recurrent spontaneous abortion (RSA)

BACKGROUND

This study investigated the molecular mechanisms of long non-coding RNAs (lncRNAs) in RSA using the lncRNA-miRNA-mRNA regulatory network.

METHODS

The present study obtained expression datasets of long non-coding RNAs (lncRNAs), messenger RNAs (mRNAs), and microRNAs (miRNAs) from blood samples of individuals with unexplained recurrent spontaneous abortion (RSA) and healthy controls. Differentially expressed lncRNAs (DELs), mRNAs (DEMs), and miRNAs (DEmiRs) were identified. A regulatory network comprising lncRNA, miRNA, and mRNA was constructed, and Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted to analyze the biological functions of DEM. Also, a protein-protein interaction (PPI) network was made and key genes were identified.

RESULTS

A total of 57 DELs, 212 DEmiRs, and 301 DEMs regarding RSA were identified. Later analysis revealed a lncRNA-miRNA-mRNA network comprising nine lncRNAs, 14 miRNAs, and 65 mRNAs. Then, the ceRNA network genes were subjected to functional enrichment and pathway analysis, which showed their association with various processes, such as cortisol and thyroid hormone synthesis and secretion, human cytomegalovirus infection, and parathyroid hormone synthesis. In addition, ten hub genes (ITGB3, GNAI2, GNAS, SRC, PLEC, CDC42, RHOA, RAC1, CTNND1, and FN1) were identified based on the PPI network results.

CONCLUSION

In summary, the outcomes of our study provided some data regarding the alteration genes involved in RSA pathogenic mechanism via the lncRNA-miRNA-mRNA network and reveal the possibility of identifying new lncRNAs and miRNAs as promising molecular biomarkers.

Pregnancy-related pelvic girdle pain affects balance in the second and third trimesters of pregnancy

INTRODUCTION

During pregnancy, many changes in the musculoskeletal system and pregnancy-related disorders affect posture and postural stability. Pregnancy-related pelvic girdle pain (PPGP) is a common disorder in pregnancy; the cause remains unknown. The purpose of the present study was to determine if PPGP affects static postural stability and its relation to the stage of pregnancy.

METHODS

Sixty-three pregnant women between the ages of 18 and 45 and between the 12th and 38th weeks of gestation were included in the study. They were divided into four groups according on the trimester and the presence of PPGP. Static balance was assessed using a force plate on firm and compliant surfaces with eyes open and closed.

RESULTS

Pregnant women with PPGP had significantly (p < 0.05) greater centre-of-pressure velocity and sway area compared to pregnant women without PPGP, especially in the third trimester of pregnancy. In the second trimester, only two significant differences in COP parameters were observed between pregnant women with and without PPGP. Pregnant women in the third trimester of pregnancy had significantly (p < 0.05) greater centre-of-pressure velocity and larger postural sway area compared to pregnant women in the second trimester of pregnancy, regardless of PPGP.

DISCUSSION AND CONCLUSION

Pregnant women with PPGP had poorer static stability when compared to pregnant women without pain, especially in the third trimester of pregnancy. The cause could be found in the poorer ability to stabilise the trunk and pelvis, poorer proprioception, and issues with automatic movement patterns.

Methods for the induction of labor: efficacy and safety

This review assessed the efficacy and safety of pharmacologic agents (prostaglandins, oxytocin, mifepristone, hyaluronidase, and nitric oxide donors) and mechanical methods (single- and double-balloon catheters, laminaria, membrane stripping, and amniotomy) and those generally considered under the rubric of complementary medicine (castor oil, nipple stimulation, sexual intercourse, herbal medicine, and acupuncture). A substantial body of published reports, including 2 large network meta-analyses, support the safety and efficacy of misoprostol (PGE1) when used for cervical ripening and labor induction. Misoprostol administered vaginally at doses of 50 μg has the highest probability of achieving vaginal delivery within 24 hours. Regardless of dosing, route, and schedule of administration, when used for cervical ripening and labor induction, prostaglandin E2 seems to have similar efficacy in decreasing cesarean delivery rates. Globally, although oxytocin represents the most widely used pharmacologic agent for labor induction, its effectiveness is highly dependent on parity and cervical status. Oxytocin is more effective than expectant management in inducing labor, and the efficacy of oxytocin is enhanced when combined with amniotomy. However, prostaglandins administered vaginally or intracervically are more effective in inducing labor than oxytocin. A single 200-mg oral tablet of mifepristone seems to represent the lowest effective dose for cervical ripening. The bulk of the literature assessing relaxin suggests this agent has limited benefit when used for this indication. Although intracervical injection of hyaluronidase may cause cervical ripening, the need for intracervical administration has limited the use of this agent. Concerning the vaginal administration of nitric oxide donors, including isosorbide mononitrate, isosorbide, nitroglycerin, and sodium nitroprusside, the higher incidence of side effects with these agents has limited their use. A synthetic hygroscopic cervical dilator has been found to be effective for preinduction cervical ripening. Although a pharmacologic agent may be administered after the use of the synthetic hygroscopic dilator, in an attempt to reduce the interval to vaginal delivery, concomitant use of mechanical and pharmacologic methods is being explored. Combining the use of a single-balloon catheter with dinoprostone, misoprostol, or oxytocin enhances the efficacy of these pharmacologic agents in cervical ripening and labor induction. The efficacy of single- and double-balloon catheters in cervical ripening and labor induction seems similar. To date, the combination of misoprostol with an intracervical catheter seems to be the best approach when balancing delivery times with safety. Although complementary methods are occasionally used by patients, given the lack of data documenting their efficacy and safety, these methods are rarely used in hospital settings.

The diverse influences of relaxin-like peptide family on tumor progression: Potential opportunities and emerging challenges

Relaxin-like peptide family exhibit differential expression patterns in various types of cancers and play a role in cancer development. This family participates in tumorigenic processes encompassing proliferation, migration, invasion, tumor microenvironment, immune microenvironment, and anti-cancer resistance, ultimately influencing patient prognosis. In this review, we explore the mechanisms underlying the interaction between the RLN-like peptide family and tumors and provide an overview of therapeutic approaches utilizing this interaction.

The physiological basis with uterine myometrium contractions from electro-mechanical/hormonal myofibril function to the term and preterm labor

Background

Most labor-related problems can be attributed to the uterine myometrium muscle, as this irritable tissue must suppress its irritability potential during pregnancy. Unfortunately, fewer studies have investigated the causes of this lack of suppression in preterm labor.

Methods

We conducted a scoping narrative review using three online databases (PubMed, Scopus, and Science Direct).

Results

The review focused on ion channel functions in the myometrium, including sodium channels [Na K-ATPase, Na-activated K channels (Slo2), voltage-gated (SCN) Na+, Na+ leaky channels, nonselective (NALCN) channels], potassium channels [KATP (Kir6) channels, voltage-dependent K channels (Kv4, Kv7, and Kv11), twin-pore domain K channels (TASK, TREK), inward rectifier Kir7.1, Ca2+-activated K+ channels with large (KCNMA1, Slo1), small (KCNN1-3), intermediate (KCNN4) conductance], and calcium channels [L-Type and T-type Ca2+ channels, calcium-activated chloride channels (CaCC)], as well as hyperpolarization-activated cation channels. These channels' functions are associated with hormonal effects such as oxytocin, estrogen/progesterone, and local prostaglandins.

Conclusion

Electromechanical/hormonal activity and environmental autocrine factors can serve as the primary practical basis for premature uterine contractions in term/preterm labor. Our findings highlight the significance of.1.the amplitude rate of hyperpolarization and the frequency of contractions,2.changes in the estrogen/progesterone ratio,3.Prostaglandins E/F involvement in initiating potential spikes and the increase of intracytoplasmic Ca2+.This narrative study highlights the range of hyperpolarization and the frequency of myometrium contractions as crucial factors. The synchronized complex progress of estrogen to progesterone ratio and prostaglandins plays a significant role in initiating potential spikes and increasing intracytoplasmic Ca2+, which further influences the contraction process during labor. Insights into myometrium physiology gained from this study may pave the way for much-needed new treatments to reduce problems associated with normal and preterm labor.

Placental RNA sequencing implicates IGFBP1 in insulin sensitivity during pregnancy and in gestational diabetes

Reduced insulin sensitivity (or greater insulin resistance) is a hallmark of normal physiology in late pregnancy and also underlies gestational diabetes mellitus (GDM) pathophysiology. We conducted transcriptomic profiling of 434 human placentas and identified a strong positive association between insulin-like growth factor binding protein 1 gene (IGFBP1) expression in the placenta and insulin sensitivity at ~ 26 weeks' gestation. Circulating IGFBP1 protein levels rose over the course of pregnancy and declined postpartum, which together with high placental gene expression levels, suggests a placental source. Higher circulating IGFBP1 levels were strongly associated with greater insulin sensitivity (lesser insulin resistance) at ~ 26 weeks' gestation in the same cohort and two additional pregnancy cohorts. In addition, low circulating IGFBP1 levels in early pregnancy predicted subsequent GDM diagnosis in two cohorts. These results implicate IGFBP1 in the glycemic physiology of pregnancy and suggest a role for placental IGFBP1 deficiency in GDM pathogenesis.

The dual and multifaceted role of relaxin-2 in cancer

The continuous increase in cancer-associated deaths despite the substantial improvement in diagnosis and treatment has sparked discussions on the need for novel biomarkers and therapeutic strategies for cancer. Although increasing evidence has demonstrated the pivotal role of relaxin-2 in multiple cancers, their role is a double-edged sword with both protumor and antitumor having been reported in various malignant tumors. Considering this dual role, it appears the biological mechanism underpinning the action of relaxin-2 in cancer is not clear and further studies to elucidate their potential as a preventive factor for cancers are of prime importance. Herein, a summarized up-to-date report on the role of relaxin-2 in human cancer including detailed clinical and experimental evidence supporting their tumor-promoting and inhibitory functions in cancer development and progression has been elucidated. Also, signaling pathways and other factors orchestrating the activities of relaxin-2 in the tumor microenvironment has been discussed. Collectively, the evidence from this review has demonstrated the need for further evaluation of the role of relaxin-2 as a diagnostic and or prognostic biomarker for cancer.

Chromogranin A: An Endocrine Factor of Pregnancy

Pregnancy is a state of physiological and hormonal changes. One of the endocrine factors involved in these processes is chromogranin A, an acidic protein produced, among others, by the placenta. Although it has been previously linked to pregnancy, no existing articles have ever managed to clarify the role of this protein regarding this subject. Therefore, the aim of the present study is to gather knowledge of chromogranin A's function with reference to gestation and parturition, clarify elusive information, and, most importantly, to formulate hypotheses for the future studies to verify.

Electrochemical biosensors for monitoring of selected pregnancy hormones during the first trimester: A systematic review

The hormones human chorionic gonadotropin, progesterone, estrogen and four of its metabolites (estradiol, estrone, estriol, estetrol), as well as relaxin play an essential role in the development of the fetus during the first trimester. Imbalances in these hormones during the first trimester have been directly linked to miscarriages. However, frequent monitoring of the hormones is limited by the current conventional centralized analytical tools that do not allow a rapid response time. Electrochemical sensing is considered an ideal tool to detect hormones owing to its advantages such as quick response, user-friendliness, low economic costs, and possibility of use in point-of-care settings. Electrochemical detection of pregnancy hormones is an emerging field that has been demonstrated primarily at research level. Thus, it is timely with a comprehensive overview of the characteristics of the reported detection techniques. This is the first extensive review focusing on the advances related to electrochemical detection of hormones linked to the first trimester of pregnancy. Additionally, this review offers insights into the main challenges that must be addressed imminently to ensure progress from research to clinical applications.

Relaxin contributes to the elevation of monocytic myeloid-derived suppressor cells in peripheral blood of pregnant canines

Tolerance towards fetal alloantigens in the maternal immune system is essential for maintaining pregnancy. Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells characterized by their ability to suppress immune activity and maintain maternal-fetal immune tolerance. However, the mechanisms underlying MDSC induction have not been elucidated. Herein, we investigated the myeloid-derived suppressor cells (MDSCs) in the peripheral blood of pregnant canines and its induction mechanism. By analyzing the concentration of MDSCs in the peripheral blood of pregnant canines, elevation of MDSCs has been observed during pregnancy. In addition, MDSCs from pregnant canines inhibit T cell activation. These results suggest that the elevated MDSCs in canine pregnancy may contribute to reduces maternal immune activity. To clarify the cause of MDSCs elevation in canine pregnancy, we analyzed the relationship between pregnancy-related hormones (estradiol, progesterone, and relaxin) and MDSCs. Serum relaxin levels, but not estradiol and progesterone, were correlated with the ratio of monocyte MDSCs. Additionally, relaxin induced monocytic MDSCs as well as inhibited T cell activation in vitro. Therefore, relaxin contributes to the elevation of monocytic MDSCs in the peripheral blood of pregnant canines. Our findings highlight the novel role of relaxin in pregnancy and contribute to a better understanding of maternal-fetal immune tolerance.

The effects of female sexual hormones on the endothelial glycocalyx

The glycocalyx is a layer composed of carbohydrate side chains bound to core proteins that lines the vascular endothelium. The integrity of the glycocalyx is essential for endothelial cells' performance and vascular homeostasis. The neuroendocrine and immune systems influence the composition, maintenance, activity and degradation of the endothelial glycocalyx. The female organism has unique characteristics, and estrogen and progesterone, the main female hormones are essential to the development and physiology of the reproductive system and to the ability to develop a fetus. Female sex hormones also exert a wide variety of effects on other organs, including the vascular endothelium. They upregulate nitric oxide synthase expression and activity, decrease oxidative stress, increase vasodilation, and protect from vascular injury. This review will discuss how female hormones and pregnancy, which prompts to high levels of estrogen and progesterone, modulate the endothelial glycocalyx. Diseases prevalent in women that alter the glycocalyx, and therapeutic forms to prevent glycocalyx degradation and potential treatments that can reconstitute its structure and function will also be discussed.

Minimally invasive, sustained-release relaxin-2 microparticles reverse arthrofibrosis

Substantial advances in biotherapeutics are distinctly lacking for musculoskeletal diseases. Musculoskeletal diseases are biomechanically complex and localized, highlighting the need for novel therapies capable of addressing these issues. All frontline treatment options for arthrofibrosis, a debilitating musculoskeletal disease, fail to treat the disease etiology-the accumulation of fibrotic tissue within the joint space. For millions of patients each year, the lack of modern and effective treatment options necessitates surgery in an attempt to regain joint range of motion (ROM) and escape prolonged pain. Human relaxin-2 (RLX), an endogenous peptide hormone with antifibrotic and antifibrogenic activity, is a promising biotherapeutic candidate for musculoskeletal fibrosis. However, RLX has previously faltered through multiple clinical programs because of pharmacokinetic barriers. Here, we describe the design and in vitro characterization of a tailored drug delivery system for the sustained release of RLX. Drug-loaded, polymeric microparticles released RLX over a multiweek time frame without altering peptide structure or bioactivity. In vivo, intraarticular administration of microparticles in rats resulted in prolonged, localized concentrations of RLX with reduced systemic drug exposure. Furthermore, a single injection of RLX-loaded microparticles restored joint ROM and architecture in an atraumatic rat model of arthrofibrosis with clinically derived end points. Finally, confirmation of RLX receptor expression, RXFP1, in multiple human tissues relevant to arthrofibrosis suggests the clinical translational potential of RLX when administered in a sustained and targeted manner.

Pregnancy outcomes after frozen-thawed embryo transfer using letrozole ovulation induction, natural, or programmed cycles

OBJECTIVE

To evaluate and compare pregnancy outcomes between letrozole ovulation induction, natural, and programmed frozen-thawed embryo transfer (FET) cycles in a population based in the United States.

DESIGN

Retrospective cohort study.

SETTING

Single university-affiliated infertility practice.

PATIENT(S)

A total of 3,148 FET cycles consisting of patients aged ≤45 years transferring blastocysts that were created from autologous oocytes between January 2015 and July 2021.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

The primary outcome was the ongoing pregnancy rate (OPR) or live birth rate (LBR). The secondary outcomes included clinical pregnancy and clinical loss rates (CLRs).

RESULT(S)

The OPR/LBR was higher among letrozole FETs than among programmed FETs (adjusted risk ratio [aRR] 1.11, 95% confidence interval [CI] 1.02-1.21) but comparable to natural FETs (aRR 1.05, 95% CI 0.96-1.14). The OPR/LBR was comparable between natural and programmed FETs (aRR 1.06, 95% CI 0.99-1.13). The CLR was lower in the natural FET group than in the programmed FET group (aRR 0.62, 95% CI 0.46-0.84). There were no differences in CLRs between letrozole and programmed FETs and between letrozole and natural FETs. Among ovulatory women, the OPR/LBR among letrozole FETs was higher than that among programmed FETs (aRR 1.16, 95% CI 1.05-1.28). The CLR among ovulatory women was significantly lower in both letrozole FETs (aRR 0.44, 95% CI 0.22-0.87) and natural FETs (aRR 0.59, 95% CI 0.43-0.80) than in programmed FETs. Among anovulatory women, the OPR/LBR in the letrozole FET group was similar to that in the programmed FET group (aRR 0.95, 95% CI 0.79-1.13).

CONCLUSION(S)

Letrozole and natural FET clinical outcomes were improved compared with programmed FET outcomes.

Can maternal hormones play a significant role in delivery mode?

The aim of this study was primarily to evaluate the levels of progesterone, oestradiol and relaxin during different delivery modes and secondarily to assess specific traits and changes in maternal pelvic dimensions during pregnancy and childbirth, in correlation with foetal size and maternal hormonal profile. Nulliparous women (n = 448) were evaluated at three different stages, during first trimester, at the time of admission for childbirth and finally just before childbirth. Each examination included clinical internal pelvimetry, blood sample collection for defining the hormones levels in peripheral maternal circulation and ultrasonographic measurements of specific variables of the pubic symphysis and the foetus. We included 304 nulliparous women divided in three groups. According to our results, there was statistically significant difference at the mean progesterone, oestradiol and relaxin range during different modes of childbirth (p-value < .01). We also found significant correlation between the newborn's weight and the changes in pubic symphysis dimensions. However, no significant association was noted between maternal hormones studied and the changes in pelvic dimensions.IMPACT STATEMENTWhat is already known on this subject? Mode of childbirth can be affected by various aspects, like maternal pelvic anatomy, foetal size and hormonal status at the time of labour. Hormonal fluctuations along with mechanical forces caused by the foetus are believed to lead to morphological alterations to promote natural vaginal childbirth.What do the results of this study add? Our results clearly showed that successful vaginal delivery is characterised by the prevalence of a hyperoestrogenic environment with higher values of intrapartum oestradiol range and significant increase in maternal serum relaxin levels. We also proved that progesterone levels do not decrease during vaginal childbirth, and we concluded that foetal size seems to be the most crucial factor causing alterations in maternal pelvis during parturition.What are the implications of these findings for clinical practice and further research? Our findings could form part of a set of key factors included in future algorithms or computerised biomechanical models for predicting potential childbirth mode. Larger multicenter studies should confirm our results and evaluate their clinical significance in the decision making to ensure safe childbirth and optimal maternal and perinatal outcomes.

Umbilical hernia: could it be the 'canary in the coal mine' for a more significant abdominal wall problem?

BACKGROUND

A considerable proportion of incisional hernias presenting to this unit evolve following simple umbilical hernia repair. Our aim was to review our series of complex ventral hernia repairs and identify the frequency of this problem. Our secondary aim was to encourage surgeons to evaluate whether any of the factors that increase the risk of recurrent hernia may be present, prior to undertaking an umbilical hernia repair.

METHODS

Observational retrospective review of a prospectively maintained single-surgeon database of consecutive patients undergoing surgery for recurrent ventral hernia. Patients presenting with recurrence at the site of a previous umbilical hernia repair were identified and their demographic data collected and analysed. A review of the published literature was performed. Patient and surgeon factors contributing to recurrence were identified and discussed.

RESULTS

Of 386 patients undergoing surgery for a recurrent ventral hernial, 102 (26.4%) were initially managed as 'simple' umbilical hernias repaired with a mesh patch or primary suture repair. 71 (69.6%) patients had undergone one or more subsequent hernia repairs prior to referral to our unit with 16 (15.6%) having had three or more repairs prior to referral.

CONCLUSION

Recurrence rates after umbilical hernia repair are likely to be much higher than surgeons and patients appreciate. There are many aspects to consider in the repair of a 'simple' umbilical hernia and we seek promote a discussion amongst surgeons that umbilical hernias be assessed as a major abdominal wall condition and not relegated to minor surgery status.

Impact of Multiple Factors on the Incidence of Developmental Dysplasia of the Hip: Risk Assessment Tool

Background and Objectives: Developmental dysplasia of the hip (DDH) is one of the most common musculoskeletal conditions in children. If not treated, it leads to disability, gait abnormalities, limb shortening, and chronic pain. Our study aims to determine the impact of multiple risk factors on the incidence of DDH and to develop an interactive risk assessment tool. Materials and Methods: We conducted a retrospective cohort study in the Outpatient Clinic for Children of the Medical University of Warsaw Hospital. The Graf classification system was used for universal ultrasonographic screening. In total, 3102 infants met the eligibility criteria. Results: The incidence of DDH in the study group was 4.45%. The incidence of DDH in the Warsaw population, Poland, during the study period was 3.73 to 5.17 (95% CI). According to the multivariate analysis, the risk factors for DDH were birth weight (OR = 2.17 (1.41−3.32)), week of delivery (OR = 1.18 (1.00−1.37)), female sex (OR = 8.16 (4.86−13.71)), breech presentation (OR = 5.92 (3.37−10.40)), physical signs of DDH (25.28 (8.77−72.83)) and positive family history in siblings (5.74 (2.68−12.31)). Our results support the recent hypothesis that preterm infants (<37 weeks) have a lower rate of DDH. Conclusions: A multivariate logistic regression predictive model was used to build the risk calculator. The DDH risk calculator will be evaluated in a prospective validation study.

Systemic vascular resistance may influence the outcome of in vitro fertilization

Introduction: The number of pregnancies obtained through in vitro fertilization (IVF) techniques are increasing, and only few studies have investigated hemodynamic variations in women undergoing IVF techniques. The aim of this study was to evaluate the hemodynamic parameters in women undergoing IVF, to assess a possible correlation between hemodynamics and embryo implantation.Methods: 45 normotensive non-obese women, age ≤ 43 years, with idiopathic or tubal infertility, referred to the Reproductive Physiopathology and Andrology Unit, Sandro Pertini Hospital, Rome, during the period 2020/2021, underwent IVF techniques. All women were evaluated with Ultra Sonic Cardiac Output Monitor (USCOM) to detect hemodynamic parameters at two different stages: at the mid-luteal phase, before the beginning of IVF, and at the day of embryo transfer (dET). All demographics and hormonal parameters in both groups were comparable. The hemodynamic parameters were compared between women with a positive β-HCG test vs. those testing negative.Results: 11 out of 45 (24,5%) women obtained positive β-HCG test. All demographics and hormonal parameters were comparable in both groups. Women with a positive β-HCG test showed statistically lower systemic vascular resistance (SVR) at mid-luteal phase (868.61 ± 100.1 vs. 1009 ± 168.4) and dET (818,9 ± 104.5 vs 1038.52 ± 150.82 dynes × s/cm⁵).Conclusions: Hemodynamic assessment can identify a more favorable pre-pregnancy cardiovascular adaptation. Embryo implantation might be positively influenced by the hemodynamic parameters, e.g. lower SVR, before the beginning of IVF techniques, and during the window of implantation.

Relaxin-2 as a Potential Biomarker in Cardiovascular Diseases

The pleiotropic hormone relaxin-2 plays a pivotal role in the physiology and pathology of the cardiovascular system. Relaxin-2 exerts relevant regulatory functions in cardiovascular tissues through the specific receptor relaxin family peptide receptor 1 (RXFP1) in the regulation of cardiac metabolism; the induction of vasodilatation; the reversion of fibrosis and hypertrophy; the reduction of inflammation, oxidative stress, and apoptosis; and the stimulation of angiogenesis, with inotropic and chronotropic effects as well. Recent preclinical and clinical outcomes have encouraged the potential use of relaxin-2 (or its recombinant form, known as serelaxin) as a therapeutic strategy during cardiac injury and/or in patients suffering from different cardiovascular disarrangements, especially heart failure. Furthermore, relaxin-2 has been proposed as a promising biomarker of cardiovascular health and disease. In this review, we emphasize the relevance of the endogenous hormone relaxin-2 as a useful diagnostic biomarker in different backgrounds of cardiovascular pathology, such as heart failure, atrial fibrillation, myocardial infarction, ischemic heart disease, aortic valve disease, hypertension, and atherosclerosis, which could be relevant in daily clinical practice and could contribute to comprehending the specific role of relaxin-2 in cardiovascular diseases.

Relaxin-2 during pregnancy according to glycemia, continence status, and pelvic floor muscle function

INTRODUCTION AND HYPOTHESIS

To investigate relaxin-2 concentration comparing gestational diabetes mellitus (GDM) and non-GDM patients during pregnancy according to urinary incontinence (UI) and pelvic function status.

METHODS

This is a cross-sectional study evaluating 282 pregnant women from 24 weeks of gestation. The participants were divided into two groups, non-GDM and GDM, according to American Diabetes Association's diabetes mellitus gestational threshold. In addition, according to subanalysis, both groups were subdivided according to the presence of pregnancy-specific urinary incontinence: non-GDM continent, non-GDM incontinent, GDM continent, and GDM incontinent. All participants filled in questionnaires on clinical, obstetric, and urinary continence status (International Consultation on Incontinence Questionnaire-Short Form, ICIQ-SF, and Incontinence Severity Index, ISI), followed by pelvic floor muscle evaluation by the PERFECT scheme in which strength, endurance, and speed of contractions were evaluated.

RESULTS

Serum relaxin-2 concentrations were significantly lower in pregnant women with pregnancy-specific urinary incontinence in both non-GDM and GDM patients, but GDM showed the lowest concentration. In addition, the stratification of the groups according to pelvic floor muscle strength showed that pregnant patients with GDM and modified Oxford scale 0-2 had significantly lower levels than those who were non-GDM and GDM with Modified Oxford Scale 3-5. Relaxin-2 level was much lower in GDM incontinent pregnant women with MOS 0-2 compared to the other three groups.

CONCLUSIONS

Lower relaxin-2 concentration was associated with the presence of pregnancy-specific urinary incontinence, but the combination of GDM, pregnancy-specific urinary incontinence, and lower levels of pelvic floor strength led to lower levels of relaxin-2 compared to the other three groups.

Sex and gender in respiratory physiology

Sex is a biological concept determined at conception. Gender is a social concept. Medicine recognises sex as a biological variable and recommends including sex as a factor in clinical practice norms and as a topic of bench and clinical research. Sex plays a role in respiratory physiology according to two pathways: hormones and anatomy, with females characterised by smaller dimensions at every level of the respiratory system. Sex hormones also play specific roles in lung inflammatory processes, breathing control and in response to diseases. The literature is extremely controversial because many factors need to be considered to avoid erroneous comparisons. The main difficulty lies in creating homogeneous groups of subjects according to age, body weight, lung/airway size, fluctuations in circulating hormone levels, and exercise protocol. Because almost all of the knowledge available in physiology is based on research in males, medicine for women is therefore less evidence-based than that being applied to men. Finally, the number of transsexual people is increasing and they represent new challenges for clinicians, due to the anatomical and physiological changes that they undergo.

Relaxin as an anti-fibrotic treatment: Perspectives, challenges and future directions

Fibrosis refers to the scarring and hardening of tissues, which results from a failed immune system-coordinated wound healing response to chronic organ injury and which manifests from the aberrant accumulation of various extracellular matrix components (ECM), primarily collagen. Despite being a hallmark of prolonged tissue damage and related dysfunction, and commonly associated with high morbidity and mortality, there are currently no effective cures for its regression. An emerging therapy that meets several criteria of an effective anti-fibrotic treatment, is the recombinant drug-based form of the human hormone, relaxin (also referred to as serelaxin, which is bioactive in several other species). This review outlines the broad anti-fibrotic and related organ-protective roles of relaxin, mainly from studies conducted in preclinical models of ageing and fibrotic disease, including its ability to ameliorate several aspects of fibrosis progression and maturation, from immune cell infiltration, pro-inflammatory and pro-fibrotic cytokine secretion, oxidative stress, organ hypertrophy, cell apoptosis, myofibroblast differentiation and ECM production, to its ability to facilitate established ECM degradation. Studies that have compared and/or combined these therapeutic effects of relaxin with current standard of care medication have also been discussed, along with the main challenges that have hindered the translation of the anti-fibrotic efficacy of relaxin to the clinic. The review then outlines the future directions as to where scientists and several pharmaceutical companies that have recognized the therapeutic potential of relaxin are working towards, to progress its development as a treatment for human patients suffering from various fibrotic diseases.

RNA profiling of laser microdissected human trophoblast subtypes at mid-gestation reveals a role for cannabinoid signaling in invasion

Human placental architecture is complex. Its surface epithelium, specialized for transport, forms by fusion of cytotrophoblast progenitors into multinucleated syncytiotrophoblasts. Near the uterine surface, these progenitors assume a different fate, becoming cancer-like cells that invade its lining and blood vessels. The latter process physically connects the placenta to the mother and shunts uterine blood to the syncytiotrophoblasts. Isolation of trophoblast subtypes is technically challenging. Upon removal, syncytiotrophoblasts disintegrate and invasive cytotrophoblasts are admixed with uterine cells. We used laser capture to circumvent these obstacles. This enabled isolation of syncytiotrophoblasts and two subpopulations of invasive cytotrophoblasts from cell columns and the endovascular compartment of spiral arteries. Transcriptional profiling revealed numerous genes, the placental or trophoblast expression of which was not known, including neurotensin and C4ORF36. Using mass spectrometry, discovery of differentially expressed mRNAs was extended to the protein level. We also found that invasive cytotrophoblasts expressed cannabinoid receptor 1. Unexpectedly, screening agonists and antagonists showed that signals from this receptor promote invasion. Together, these results revealed previously unseen gene expression patterns that translate to the protein level. Our data also suggested that endogenous and exogenous cannabinoids can affect human placental development.

Summary: Transcriptomic and proteomic profiling of laser captured human trophoblasts showed that placental cells lining uterine arteries express cannabinoid receptor 1. Functional analyses suggest that endogenous/exogenous cannabinoids could affect placentation.

The male rectus diastasis: a different concept?

PURPOSE

More interest in the treatment of rectus diastasis has been evoked lately. Following the postpartum females from a great distance, the middle-aged males living with obesity are the second most common group of rectus diastasis patients. Although gender differences are considered frequently in regard to cosmetic appearance and symptoms, it is less obvious in classifications and subsequent treatment strategies. Is a unisex approach of rectus diastasis still applicable? The lack of a firm answer warrants this review of the current literature.

METHODS

An explorative free-text multi-database bibliographic search (Pubmed/CENTRAL/EMBASE/PEDro/Scholar) was performed with the focus on the rectus diastasis in males. Anticipating the limited references, the design was a non-systematic review. All studies, regardless of study type, language or time period, describing etiology, symptoms, classification and/or treatment options were eligible for inclusion. From the articles retrieved out of this search, additional references were identified by a manual search among the cited references.

RESULTS

The multi-database search resulted in a total of 7633 records. Based on the title and abstract 95 records were full text assessed for eligibility. Eleven studies were identified as relevant, six by cross-reference and another four by hand-search were added to provide an insight in gender-specific aspects in rectus diastase. Hereditary causes are differences in collagen-like composition of types and concomitant abdominal aneurysm as well as gender differences in the linea alba architecture. Acquired etiology is distributed into both absolute pressure by visceral obesity and relative pressure caused by weight lifting or improper exercises. Furthermore, the impact of muscle thickness and age are considered as influencers of biomechanics. Gender differences can also play a role in symptoms of body image and core stability. It is known that there are anatomical differences between male and female persons; more transverse fibers are found in infra-umbilical region in women. In classifications the awareness of male rectus diastasis is limited, treatment outcome studies are scarce on males.

CONCLUSION

An overview of male-specific aspects of rectus diastasis is provided, underlining that key aspects surrounding rectus diastasis in males differ from females. Although males are the minority of rectus diastasis patients, we recommend that the male rectus diastasis as a concept should be specifically acknowledged in classifications systems and study outcome reporting to evaluate this subgroup more accurately in the future.

Does exercise during pregnancy impact organs or structures of the maternal-fetal interface?

Exercise during pregnancy has been shown to be associated with improved health outcomes both during and after pregnancy for mother and fetus across the lifespan. Increasing physical activity and reducing sedentary behaviour during pregnancy have been recommended by many researchers and clinicians-alike. It is thought that the placenta plays a central role in mediating any positive or negative pregnancy outcomes. The positive outcomes obtained through prenatal exercise are postulated to result from exercise-induced regulation of maternal physiology and placental development. Considerable research has been performed to understand the placenta's role in pregnancy-related diseases, such as preeclampsia, fetal growth restriction, and gestational diabetes mellitus. However, little research has examined the potential for healthy lifestyle and behavioural changes to improve placental growth, development, and function. While the placenta represents the critical maternal-fetal interface responsible for all gas, nutrient, and waste exchange between the mother and fetus, the impact of exercise during pregnancy on placental biology and function is not well known. This review will focus on prenatal exercise and its promising influence on the structures of the maternal-fetal interface, with particular emphasis on the placenta. Potential molecular mechanistic hypotheses are presented to aid future investigations of prenatal exercise and placental health.

The levels of relaxin and amino acids play a critical role in women with variable degree of preparedness for labour

Underlying biochemical factors that contribute towards the preparedness for labour and ripening of the cervix remain largely unknown. We aimed to characterize metabolic and hormonal determinants that constitute the preparedness for labour in women. The aim of the research was to study the content of relaxin and amino acids involved in its formation in primiparous pregnant women with various degrees of birth preparedness. Materials and methods: Prospective study has been conducted on 115 primiparous women at 38-40 weeks of gestation. Biochemical methods were used to analyse relaxin and amino acid levels in pregnant women with varying degree of birth preparedness. Results: the obtained data from the study indicate importance role of relaxin in the underlying pathogenesis in women with variable degree of preparedness for labour. The results allow to use the levels of relaxin serum as a predictor of the state of the birth canal. Furthermore, the amino acids are known to participate in various critical metabolic processes and play an important role is orchestrating many essential pathways in the body. We present the analysis of amino acids involved in the formation of relaxin in the serum of pregnant women. Our analysis has shown that amino acid imbalance leads to disruption of energy metabolism and blood flow rate, resulting in metabolic, structural and functional changes in the cervix at the onset of labour. Conclusion: considering the mechanisms of the possible influence of relaxin and amino acids on the cervical ripening, we concluded that correcting amino acid imbalance and normalising relaxin levels should be included in preinduction of labour therapeutic regimen. This would be an important step in improving the perinatal outcomes

Relaxin abrogates genomic remodeling of the aged heart

"Healthy" aging drives structural and functional changes in the heart including maladaptive electrical remodeling, fibrosis and inflammation, which lower the threshold for cardiovascular diseases such as heart failure (HF) and atrial fibrillation (AF). Despite mixed results in clinical trials, Relaxin-therapy for 2-days reduced mortality by 37% at 180-days post-treatment, in patients with acute decompensated HF. Relaxin's short lifespan (2-3h) but long-lasting protective actions suggested that relaxin acts at a genomic level to reverse maladaptive remodeling in AF, HF and aging. Our recent studies showed that a 2-week treatment with Relaxin (0.4mg/kg/day) of aged (24months old F-344 rats) increases the expression of voltage-gated Na⁺ channels (mRNA, Nav1.5 and I_Na), connexin-43, abrogates inflammatory and immune responses and reverses myocardial fibrosis and cellular hypertrophy of the aged hearts. Relaxin acts directly at a wide range of cell types in the cardiovascular system that express its cognate GPCR receptor, RXFP1. RNA-seq analysis of young and aged hearts with and without Relaxin treatment revealed that "normal" aging altered the expression of ~10% of genes expressed in the ventricles, including: ion channels, components of fibrosis, hemodynamic biomarkers, immune and inflammatory responses which were reversed by Relaxin. The extensive cardiovascular remodeling caused by Relaxin was mediated through the activation of the Wnt/β-catenin signaling pathway which was otherwise suppressed by in adult cardiomyocytes intracellular by cytosolic Dickkopf1 (Dkk1). Wnt/β-catenin signaling is a mechanism that can explain the pleiotropic actions of Relaxin and the marked reversal of genomic changes that occur in aged hearts.

Progesterone receptor blockers: historical perspective, mode of function and insights into clinical and scientific applications

Antigestagens (antiprogestins) are functional competitors of progesterone (P4) that prevent P4 from mediating its biological functions either by suppressing its production or blocking its function. Among the latter are progesterone antagonists, competitors of P4 binding to its nuclear receptor PGR, which have found application in both human and veterinary medicine, in particular in small animal practice for the prevention of nidation and the interruption of pregnancy. Depending on their mode of action, progesterone receptor antagonists can be divided into 2 classes. Class I antagonists bind to the PGR but fail to induce its binding to promoters of target genes (competitive inhibitors). Class II antigestagens, including aglepristone used in veterinary medicine, bind to the PGR, activate its association with a promoter, but interfere with the downstream signalling cascades, e. g., by recruiting transcriptional repressors. They act thereby as transdominant repressors exerting negative effects on target gene expression. Importantly for experimental sciences, as active antagonists, class II antagonists do not require the presence of the natural ligand for their action. Besides their clinical application, antigestagens are used in research for investigating P4-dependent physiological and pathological processes. Here an overview of the history and the current usage of progesterone receptor antagonists in veterinary medicine and research is presented.

Relaxin-2 May Suppress Endometriosis by Reducing Fibrosis, Scar Formation, and Inflammation

BACKGROUND

Relaxin (RLX)-2, produced by the corpus luteum and placenta, is known to be potentially effective in fibrotic diseases of the heart, lungs, kidneys, and bladder; however, its effectiveness in endometriosis has not yet been investigated. In the present study, we conducted a comprehensive study on the effect of RLX-2 on endometriosis. We checked the expressions of LGR-7, a primary receptor of RLX-2, in endometriomas using immunohistochemistry. Endometriotic stromal cells (ESCs) purified from surgical specimens were used in in vitro experiments. The effects of RLX-2 on ESCs were evaluated by quantitative-PCR, ELISA, and Western blotting. Gel contraction assay was used to assess the contraction suppressive effect of RLX-2. The effect of RLX-2 was also examined in the endometriosis mouse model. LGR-7 was expressed in endometriotic lesions. In ESCs, RLX-2 increased the production of cAMP and suppressed the secretion of interleukin-8, an inflammatory cytokine, by 15% and mRNA expression of fibrosis-related molecules, plasminogen activator inhibitor-1 (PAI-1), and collagen-I by approximately 50% (p < 0.05). In the gel contraction assay, RLX-2 significantly suppressed the contraction of ESCs, which was cancelled by removing RLX-2 from the medium or by adding H89, a Protein Kinase A (PKA) inhibitor. In ESCs stimulated with RLX-2, p38 MAPK phosphorylation was significantly suppressed. In the endometriosis mouse model, administration of RLX-2 significantly decreased the area of the endometriotic-like lesion with decreasing fibrotic component compared to non-treated control (p = 0.01). RLX-2 may contribute to the control of endometriotic lesion by suppressing fibrosis, scar formation, and inflammation.

Adaptation of lung, chest wall, and respiratory muscles during pregnancy: preparing for birth

A plethora of physiological and biochemical changes occur during normal pregnancy. The changes in the respiratory system have not been as well elucidated, in part because radioimaging is usually avoided during pregnancy. We aimed to use several noninvasive methods to characterize the adaptation of the respiratory system during the full course of pregnancy in preparation for childbirth. Eighteen otherwise healthy women (32.3 ± 2.8 yr) were recruited during early pregnancy. Spirometry, optoelectronic plethysmography, and ultrasonography were used to study changes in chest wall geometry, breathing pattern, lung and thoraco-abdominal volume variations, and diaphragmatic thickness in the first, second, and third trimesters. A group of nonpregnant women were used as control subjects. During the course of pregnancy, we observed a reorganization of rib cage geometry, in shape but not in volume. Despite the growing uterus, there was no lung restriction (forced vital capacity: 101 ± 15% predicted), but we did observe reduced rib cage expansion. Breathing frequency and diaphragmatic contribution to tidal volume and inspiratory capacity increased. Diaphragm thickness was maintained (1st trimester: 2.7 ± 0.8 mm, 3rd trimester: 2.5 ± 0.9 mm; P = 0.187), possibly indicating a conditioning effect to compensate for the effects of the growing uterus. We conclude that pregnancy preserved lung volumes, abdominal muscles, and the diaphragm at the expense of rib cage muscles.NEW & NOTEWORTHY Noninvasive analysis of the kinematics of the chest wall and the diaphragm during resting conditions in pregnant women revealed significant changes in the pattern of thoracoabdominal breathing across the trimesters. That is, concomitant with the progressive changes of chest wall shape, the diaphragm increased its contribution to both spontaneous and maximal breathing, maintaining its thickness despite its lengthening due to the growing uterus. These results suggest that during pregnancy the diaphragm is conditioned to optimize its active role provided during parturition.

Sensitivity of the fasciae to sex hormone levels: Modulation of collagen-I, collagen-III and fibrillin production

Although it is now recognized that women suffer from myofascial pain to a greater extent than men, and that the muscular fasciae can respond to hormonal stimuli, thanks to the expression of sex hormone receptors, how the fasciae can modify their structure under hormonal stimulation is not clear. In this work, an immunocytochemical analysis of collagen-I, collagen-III and fibrillin were carried out on fibroblasts isolated from human fascia lata after in vitro treatment with various levels of sex hormones β-estradiol and/or relaxin-1, according to the phases of a woman's period (follicular, periovulatory, luteal, post-menopausal phases and pregnancy). This study demonstrates for the first time that fascial cells can modulate the production of some components of the extracellular matrix according to hormone levels, when treated with β-estradiol: collagen-I falls from 6% of positivity in the follicular phase to 1.9 in the periovulatory phase. However, after the addition of relaxin-1 to the cell culture, the production of extracellular matrix decreased and remained at the same level (1.7% of collagen-I, at both follicular and periovulatory levels of hormones). These results confirm the antifibrotic function of relaxin-1, thanks to its ability to reduce matrix synthesis. They are also a first step in our understanding of how some hormonal dysfunctions in women can cause a dysregulation of extracellular matrix production in fasciae.

Serum relaxin and cervical length for prediction of spontaneous preterm birth in second-trimester symptomatic women

OBJECTIVE

To investigate whether serum relaxin level is associated with preterm birth in symptomatic women, either as a standalone test or in the context of a combined model of serum relaxin and cervical length (CL).

METHODS

This was a case-control study of women with a singleton pregnancy who presented between 24 + 0 and 26 + 6 weeks' gestation with threatened preterm labor and intact membranes. CL, full blood count, C-reactive protein level and maternal demographics were recorded at presentation, and blood samples were taken for relaxin measurement. Parameters were compared between women who delivered preterm (before 37 weeks) (n = 46) and those delivering at term (n = 66). Logistic regression with receiver-operating characteristics (ROC) curve analysis was used to assess significant predictors for birth before 37 and before 34 weeks.

RESULTS

Women delivering before 37 weeks had higher mean serum relaxin levels and lower mean CL than those delivering at term (P < 0.0001). Relaxin alone had 63% (95% CI, 49-75%) sensitivity for birth before 37 weeks and 61% (95% CI, 47-74%) for birth before 34 weeks, at a 10% false-positive rate (FPR). Serum relaxin levels did not correlate with CL; a combined model of the two predictors had an area under the ROC curve of 0.895 (95%CI, 0.835-0.954) for the prediction of birth before 37 weeks and 0.869 (95% CI, 0.802-0.937) for birth before 34 weeks (n =  44). Serum relaxin > 1010 pg/mL had 58% sensitivity for prediction of preterm birth in women with a CL > 15 mm, at a 10% FPR.

CONCLUSIONS

High serum relaxin level is associated with an increased risk of preterm birth in second-trimester symptomatic women with intact membranes. A combination of serum relaxin and CL increases predictive accuracy for preterm birth. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Relaxin 2/RXFP1 Signaling Induces Cell Invasion via the β-Catenin Pathway in Endometrial Cancer

Relaxin is known to play an important role in animal pregnancies, including those of humans. It is suggested that relaxin induces aggressive cell growth and invasiveness in several types of cancer, including endometrial cancer. However, the mechanisms of relaxin remain largely unclear. In this study, we examined the effects of relaxin 2 (RLN2), the major circulating relaxin in humans, on human endometrial carcinoma cell lines. RLN2 treatment induced invasion in HEC-1B and Ishikawa cells. RLN2-induced cell invasion was significantly decreased by transfection of relaxin receptor 1 (RXFP1) siRNAs. The β-catenin inhibitor, XAV939, also significantly inhibited the RLN2-induced cell invasions. Both a decrease of cadherin expression and an increase of β-catenin phosphorylation were observed in response to the RLN2 treatment in HEC-1B and Ishikawa cells. We then examined RLN2 and RXFP1 expression in 80 human endometrioid endometrial carcinoma tissues. RLN2 immunoreactivity was detected in the human endometrial carcinoma cells and had a correlative tendency with histological grade and RXFP1. These results suggest that adherens junctions in cancer cells are weakened by the breakdown of the cadherin/catenin complex, which is induced by β-catenin phosphorylation via RLN2/RXFP1 signaling.

Is maternal serum relaxin associated with preterm delivery in Chinese pregnant women? A meta-analysis

Objective: A meta-analysis was performed to study the relationship between serum relaxin and preterm delivery in women with singleton pregnancies without estrogen stimulation. Methods: Cohort and case-control studies were identified through searching databases (PubMed, Embase, Ovid, CBM, Wan fang, VIP, and CNKI). We carried out a continuous variable meta-analysis. The outcome was preterm delivery (gestation age <37 weeks). Results: Fifteen studies were included, involving 1607 women with a singleton pregnancy. The pooled standard mean deviation (SMD) of 15 studies was 0.559 (95%CI: 0.002-1.196) and the heterogeneity was 96.6%. To reduce the heterogeneity, we chose random effects model and made subgroup analysis according to gestational age at sample testing (<18 weeks and ≥18 weeks) and race of included pregnant women. The pooled SMD of gestational age at sample testing ≥18 weeks and Chinese were 1.19 (95%CI: 0.63-1.75) and 1.61 (95%CI: 0.82-2.41) and the heterogeneity values (measured by I²) were 93.5% and 76.5%, respectively. Conclusions: Elevated maternal serum relaxin of later than 18 weeks of gestational age is associated with singleton preterm birth in Chinese women. It might be an important information to prevent singleton preterm delivery in Chinese women. What's already known about this topic? Previous reports reveal that there is a relationship between elevated maternal serum relaxin and preterm birth. However, the included articles contained twin pregnancies and estrogen stimulation, which obviously resulted in higher relaxin concentrations. What does this study add?

Low-dose hCG as trigger day and 35 hr later have different ovarian hyperstimulation syndrome occurrence in females undergoing In vitro fertilization: An RCT

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication, which can cause high morbidity and mortality. Use of gonadotropin releasing hormone (GnRH) agonist instead of human chorionic gonadotropin (hCG) in GnRH antagonist cycles causes luteinizing hormone surge by GnRH stimulation which reduces the risk of OHSS by reducing the total amount of gonadotropin; however, there is no possibility of transferring fresh embryos.

OBJECTIVE

The current study aimed to evaluate the effect of hCG along with GnRH agonist administration in the occurrence of OHSS and pregnancy rate in females undergoing in vitro fertilization.

MATERIALS AND METHODS

The current randomized clinical trial was conducted on 80 cases in 2 groups. Gonal-F was used to stimulate the oocyte from the second day of menstruation. When follicle size was 12-14 mm, GnRH antagonist was added to the protocol till the detection of more than two follicles greater than 18 mm. Then, GnRH agonist was added to the protocol as a trigger. In group A, 35 hr after the administration of GnRH agonist, the low-dose human hCG, 1500 IU, was used. In group B, low-dose hCG, 1500 IU, was used at the same time by GnRH agonist administration. The rate of pregnancy, OHSS, and its severity were compared between 2 groups within 2 wk.

RESULTS

There was no significant difference regarding chemical and clinical pregnancies between the 2 groups. Severe OHSS was significantly higher in group B (p= 0.03).

CONCLUSION

Administration of hCG 35 hr after GnRH agonist administration results in lower rate of severe OHSS.

Serelaxin improves cardiac and renal function in DOCA-salt hypertensive rats

Serelaxin, a recombinant form of the naturally occurring peptide hormone relaxin-2, is a pleiotropic vasodilating hormone that has been studied in patients with acute heart failure. In this study, the effects of serelaxin on cardiac and renal function, fibrosis, inflammation and lipid accumulation were studied in DOCA-salt treated rats. Uninephrectomized rats were assigned to two groups: controls provided with normal drinking water and DOCA provided with DOCA pellets and sodium chloride drinking water. After 4 weeks, the DOCA-salt rats were randomly selected and implanted with osmotic minipumps delivering vehicle or serelaxin for another 4 weeks. Treatment with serelaxin prevented cardiac and renal dysfunction in DOCA-salt rats. Serelaxin prevented cardiac and renal fibrosis, as determined by Picrosirius Red staining and Second Harmonic Generation (SHG) Microscopy. Treatment of DOCA-salt rats with serelaxin decreased renal inflammation, including the expression of TGF-β, NFκB, MCP-1, IL-1, IL-6, ICAM-1, VCAM-1 and CD68 macrophages. Serelaxin also decreased lipid accumulation in kidney in part by decreasing SREBP-1c, SREBP-2, ChREBP, FATP1, HMGCoAR, and LDL receptor, and increasing Acox1 and ABCA1. In summary, serelaxin reversed DOCA-salt induced cardiac and renal dysfunction.

Effect of single post-ovulatory administration of mifepristone (RU486) on transcript profile during the receptive period in human endometrium

Progesterone regulates uterine function during the luteal phase and is essential for the acquisition of endometrial receptivity. The objective of the present study was to identify endometrial transcripts whose expression is altered during the window of implantation after the administration of 200 mg of the antiprogestin mifepristone, 48 h after the LH peak (LH+2, LH+0=LH peak), and to determine the relationship of these transcripts with those regulated during the acquisition of receptivity. Endometrial samples were obtained in LH+7 from seven women of proven fertility, each one contributing with one cycle treated with placebo and another with mifepristone. Additionally, endometrial samples were obtained in LH+2 and LH+7 during a single untreated spontaneous cycle from seven normal fertile women as a reference. DNA microarrays were used to identify transcripts significantly regulated (defined as ≥2.0-fold change with false discovery rate below 1% usingt-test) with the administration of mifepristone vs placebo, or during the transition from pre-receptive to receptive (LH+2 vs LH+7). Approximately 2000 transcripts were significantly regulated in both comparisons (mifepristone vs placebo and LH+2 vs LH+7), but only 777 of them were coincident and displayed opposite regulation except for 25. The mRNA level for eight selected genes regulated by mifepristone was confirmed by real-time RT-PCR. We conclude that not all changes in endometrial transcript levels occurring in the transition from LH+2 to LH+7 seem to be regulated by the progesterone receptor and ∼37% of the genes whose transcript levels changed by effect of mifepristone could be associated with the acquisition of receptivity.

Association of number of retrieved oocytes with live birth rate and birth weight: an analysis of 231,815 cycles of in vitro fertilization

OBJECTIVE

To determine if number of retrieved oocytes correlates with live birth rate and incidence of low birth weight (LBW).

DESIGN

Retrospective cohort.

SETTING

Not applicable.

PATIENT(S)

Women undergoing fresh embryo transfer with the use of either autologous (n = 194,627) or donor (n = 37,188) oocytes whose cycles were reported to the Society for Assisted Reproductive Technology in the years 2004-2010.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Live birth rate, birth weight, birth weight z-score, LBW.

RESULT(S)

For both autologous and donor oocyte cycles, increasing number of retrieved oocytes paralleled live birth rate and embryos available for cryopreservation in most analyses, with all models adjusted for age and previous births. For cycles achieving singleton pregnancy with the use of autologous oocytes via transfer of two embryos, a higher number of retrieved oocytes was associated with lower mean birth weight, lower birth weight z-score, and greater incidence of LBW. In contrast, for cycles using donor oocytes, there was no association of number of retrieved oocytes with measures of birth weight.

CONCLUSION(S)

A higher number of retrieved oocytes was associated with an increased incidence of LBW in autologous singleton pregnancies resulting from transfer of two embryos, but not in donor oocyte cycles. Although the effect of high oocyte number on the incidence of LBW in autologous cycles was of modest magnitude, further study is warranted to determine if a subgroup of women may be particularly vulnerable.

Prediction of preterm birth in twin gestations using biophysical and biochemical tests

The objective of this study was to determine the performance of biophysical and biochemical tests for the prediction of preterm birth in both asymptomatic and symptomatic women with twin gestations. We identified a total of 19 tests proposed to predict preterm birth, mainly in asymptomatic women. In these women, a single measurement of cervical length with transvaginal ultrasound before 25 weeks of gestation appears to be a good test to predict preterm birth. Its clinical potential is enhanced by the evidence that vaginal progesterone administration in asymptomatic women with twin gestations and a short cervix reduces neonatal morbidity and mortality associated with spontaneous preterm delivery. Other tests proposed for the early identification of asymptomatic women at increased risk of preterm birth showed minimal to moderate predictive accuracy. None of the tests evaluated in this review meet the criteria to be considered clinically useful to predict preterm birth among patients with an episode of preterm labor. However, a negative cervicovaginal fetal fibronectin test could be useful in identifying women who are not at risk for delivering within the next week, which could avoid unnecessary hospitalization and treatment. This review underscores the need to develop accurate tests for predicting preterm birth in twin gestations. Moreover, the use of interventions in these patients based on test results should be associated with the improvement of perinatal outcomes.