Association between the serum estrone-to-estradiol ratio and parameters related to glucose metabolism and insulin resistance in women with polycystic ovary syndrome

Objective: We aimed to evaluate associations between the ratio of serum estrone (E1) to estradiol (E2) and parameters related to serum glucose metabolism and insulin resistance in women with polycystic ovary syndrome (PCOS). Methods: In total, 133 women between the ages of 18 and 33 diagnosed with PCOS were enrolled in this study. All participants with PCOS underwent blood tests to determine hormonal and biochemical metabolic parameters and a standard 2-hour 75-g oral glucose tolerance test. They were divided into two groups according to the serum E1-to-E2 ratio: group 1 (E1/E2 ratio <2.0) and group 2 (E1/E2 ratio ≥2.0). Results: In the comparative analysis, the waist-to-hip ratio (WHR) was the only clinical variable that was significantly different between the two groups. Patients with a higher E1/E2 ratio showed higher fasting insulin levels, homeostasis model for insulin resistance, and postprandial glucose levels at 2 hours (PPG2). In a correlation analysis, only PPG2 was significantly related to the serum E1/E2 ratio. However, after controlling for the confounding effects of body mass index (BMI) and WHR, fasting glucose was also significantly correlated with the serum E1/E2 ratio. Conclusion: Women with PCOS with a higher serum E1/E2 ratio were found to be more likely to show higher fasting insulin and postprandial glucose levels. Significant correlations were found between the serum E1/E2 ratio and both fasting and postprandial serum glucose levels after adjusting for BMI and WHR in women with PCOS.

Adipose tissue-derived mesenchymal stem cells reduce endometriosis cellular proliferation through their anti-inflammatory effects

Objective: Endometriosis is a chronic debilitating inflammatory condition characterized by the presence of endometrial tissues outside the uterine cavity. Pelvic soreness and infertility are the usual association. Due to the poor effectiveness of the hormone therapy and the high incidence of recurrence following surgical excision, there is no single effective option for management of endometriosis. Mesenchymal stem cells (MSCs) are multipotent stromal cells studied for their broad immunoregulatory and anti-inflammatory properties; however, their efficiency in endometriosis cases is still a controversial issue. Our study aim was to evaluate whether adipose tissue-derived MSCs (AD-MSCs) could help with endometriosis through their studied anti-inflammatory role. Methods: Female Wistar rats weighting 180 to 250 g were randomly divided into two groups: group 1, endometriosis group; established by transplanting autologous uterine tissue into rats’ peritoneal cavities and group 2, stem cell treated group; treated with AD-MSCs on the 5th day after induction of endometriosis. The proliferative activity of the endometriosis lesions was evaluated through Ki67 staining. Quantitative estimation of interferon γ, tumor necrosis factor-α, interleukin (IL)-6, IL-1β, IL-10, and transforming growth factor β expression, as well as immunohistochemical detection of CD68 positive macrophages, were used to assess the inflammatory status. Results: The size and proliferative activity of endometriosis lesions were significantly reduced in the stem cell treated group. Stem cells efficiently mitigated endometriosis associated chronic inflammatory reactions estimated through reduction of CD68 positive macrophages and the expression of the proinflammatory cytokines. Conclusion: Stem cell therapy can be considered a novel remedy in endometriosis possibly through its anti-inflammatory and antiproliferative properties.

Impact of vitamin D3 supplementation on the in vitro growth of mouse preantral follicles

Objective: We investigated the impact of vitamin D3 (VD3) supplementation during mouse preantral follicle culture in vitro and the mRNA expression of 25-hydroxylase (CYP2R1), 1-alpha-hydroxylase (CYP27B1), and vitamin D receptor (VDR) in mouse ovarian follicles at different stages.Methods: Preantral follicles were retrieved from 39 BDF1 mice (7–8 weeks old) and then cultured in vitro for 12 days under VD3 supplementation (0, 25, and 50 pg/mL). Follicular development and the final oocyte acquisition were assessed. Preantral follicles were retrieved from 15 other BDF1 mice (7–8 weeks old) and cultured without VD3 supplementation. Three stages of mouse ovarian follicles were obtained (preantral, antral, and ruptured follicles). Total RNA was extracted from the pooled cells (from 20 follicles at each stage), and then reverse transcriptase-polymerase chain reaction was performed to identify mRNA for CYP2R1, CYP27B1, and VDR.Results: The survival of preantral follicles, rates of antrum formation and ruptured follicles (per initiated follicle) and the number of total or mature oocytes were all comparable among the three groups. Both CYP2R1 and CYP27B1 were expressed in antral and ruptured follicles, but not in preantral follicles. VDR was expressed in all three follicular stages.Conclusion: VD3 supplementation in vitro (25 or 50 pg/mL) did not enhance mouse follicular development or final oocyte acquisition. Follicular stage-specific expression of CYP2R1, CYP27B1, and VDR was observed.

Effects of prematuration culture with a phosphodiesterase-3 inhibitor on oocyte morphology and embryo quality in in vitro maturation

Objective: The study assessed the developmental potential of germinal vesicle (GV) oocytes subjected to in vitro maturation (IVM) after prematuration culture with cilostamide (a phosphodiesterase-3 inhibitor) and the impact of cilostamide exposure on the morphology of meiosis II (MII) oocytes and subsequent embryo quality. Methods: In total, 994 oocytes were collected from 63 patients. Among 307 GV oocytes, 140 oocytes were selected for the experimental group and 130 oocytes for the control group. The denuded GV-stage oocytes were cultured for 6 hours with cilostamide in the experimental group and without cilostamide in the control group. After 6 hours, the oocytes in the experimental group were washed and transferred to fresh IVM medium. The maturational status of the oocytes in both groups was examined at 26, 36, and 48 hours. Fertilization was assessed at 18 hours post-intracytoplasmic sperm injection. Embryo quality was assessed on days 3 and 5.Results: In total, 92.1% of the oocytes remained in the GV stage, while 6.4% converted to the MI stage (p<0.01) after cilostamide exposure. In both groups, more MII oocytes were observed at 36 hours (25.8% vs. 21.5%) than at 26 hours (10.8% vs. 14.6%) and 48 hours (13% vs. 7.9%) (p>0.05). With the advenet of cilostamide, blastocyst quality was better in the experimental group than in the control group (p<0.05). Conclusions: Cilostamide effectively blocked nuclear maturation and promoted cytoplasmic growth. Prematuration culture with cilostamide enabled synchronization between cytoplasmic and nuclear maturity, resulting in better blastocyst outcomes.

The antioxidant roles of L-carnitine and N-acetyl cysteine against oxidative stress on human sperm functional parameters during vitrification

Objective: Amino acids can protect sperm structure in cryopreservation due to their antioxidant properties. Therefore, the present study aimed to investigate the protective effect of L-carnitine (LC) and N-acetyl cysteine (NAC) on motility parameters, plasma membrane integrity (PMI), mitochondrial membrane potential (MMP), DNA damage, and human sperm intracellular reactive oxygen species (ROS) during vitrification. Methods: Twenty normal human sperm samples were examined. Each sample was divided into six equal groups: LC (1 and 10 mM), NAC (5 and 10 mM), and cryopreserved and fresh control groups. Results: The groups treated with LC and NAC showed favorable findings in terms of motility parameters, DNA damage, and MMP. Significantly higher levels of intracellular ROS were observed in all cryopreserved groups than in the fresh group (p≤0.05). The presence of LC and NAC at both concentrations caused an increase in PMI, MMP, and progressive motility parameters, as well as a significant reduction in intracellular ROS compared to the control group (p≤0.05). The concentrations of the amino acids did not show any significant effect.Conclusion: LAC and NAC are promising as potential additives in sperm cryopreservation.

Progress in human ovarian rejuvenation: Current platelet-rich plasma and condensed cytokine research activity by scope and international origin

Objective: As clinicians and patients await consensus on intraovarian platelet-rich plasma (PRP) treatment, this project evaluated contemporary research trends in the literature. Methods: A PubMed/NLM search aggregated all ovarian PRP-related publications (n=54) to evaluate their scope, abstract utility, submission-to-publication interval, journal selected, article processing charge (APC), free reader access to full-text manuscripts, number and nationality of authors, and inclusion of international collaborators. The NIH Clinical Trials database was also audited. Results: Published output on intraovarian PRP has increased consistently since 2016, especially among investigators in Greece, Iran, USA, and Turkey. Between 2013 and 2021, 42 articles met the relevancy criteria, of which 40.5% reported clinical studies, small series, or case reports, 33% described experimental animal models, and 23.8% were opinion/review papers. Only two works included a placebo control group. The submission-to-publication interval (mean±standard deviation) was 130±96 days, there were 5.9±3.2 authors per project, and journals invoiced US $1,642±1,466 (range, $0–$3,860) for APCs. Conclusion: There was no correlation between APC and time to publish (Pearson’s r=–0.01). Abstract content was inconsistent; sample size and patient age were often missing, yet free full-text “open access” was available for most publications (59.5%). The NIH Clinical Trials portal lists eight registered studies on “ovarian rejuvenation,” of which two are actively recruiting patients, while four have been terminated or have an uncertain status. Two studies have concluded, with results from one posted to the NIH website. PRP and its derivatives for ovarian treatment show early promise, but require further investigation. Research is accelerating and should be encouraged, particularly placebo-controlled randomized clinical trials.

Decorin: a multifunctional proteoglycan involved in oocyte maturation and trophoblast migration

Decorin (DCN) is a proteoglycan belonging to the small leucine-rich proteoglycan family. It is composed of a protein core containing leucine repeats with a glycosaminoglycan chain consisting of either chondroitin sulfate or dermatan sulfate. DCN is a structural component of connective tissues that can bind to type I collagen. It plays a role in the assembly of the extracellular matrix (ECM), and it is related to fibrillogenesis. It can interact with fibronectin, thrombospondin, complement component C1, transforming growth factor (TGF), and epidermal growth factor receptor. Normal DCN expression regulates a wide range of cellular processes, including proliferation, migration, apoptosis, and autophagy, through interactions with various molecules. However, its aberrant expression is associated with oocyte maturation, oocyte quality, and poor extravillous trophoblast invasion of the uterus, which underlies the occurrence of preeclampsia and intrauterine growth restriction. Spatiotemporal hormonal control of successful pregnancy should regulate the concentration and activity of specific proteins such as proteoglycan participating in the ECM remodeling of trophoblastic and uterine cells in fetal membranes and uterus. At the human feto-maternal interface, TGF-β and DCN play crucial roles in the regulation of trophoblast invasion of the uterus. This review summarizes the role of the proteoglycan DCN as an important and multifunctional molecule in the physiological regulation of oocyte maturation and trophoblast migration. This review also shows that recombinant DCN proteins might be useful for substantiating diverse functions in both animal and in vitro models of oogenesis and implantation.

Anorexigenic peptide (leptin, obestatin, nesfatin-1) levels and their impact on assisted reproductive technology treatment outcomes in patients with polycystic ovary syndrome

Objective: In this study we aimed to assess anorexigenic peptide levels in patients with or without polycystic ovary syndrome (PCOS) and their effects on assisted reproductive treatment (ART) outcomes. Methods: A prospective case-control study was conducted in a tertiary care university-based ART clinic. Eighty-three patients were included in the study. The PCOS group included 41 patients, and the non-PCOS group included 42 controls. The 2003 Rotterdam criteria were used for PCOS patient selection. The ART indications in the non-PCOS group were tubal factor or unexplained infertility. Venous blood samples were taken on the third day of the menstrual cycle to determine the serum anorexigenic peptide levels. The enzyme-linked immunosorbent assay method was used for laboratory analyses. Results: In the PCOS group, serum obestatin levels were significantly lower than in the control group, but serum anorexigenic peptide levels were similar in PCOS patients with or without clinical pregnancy. Ovarian hyperstimulation syndrome (OHSS) was diagnosed only in PCOS patients, and the obestatin levels of OHSS patients were significantly lower than those of other PCOS patients. Conclusions: Baseline anorexigenic peptide levels did not affect the clinical pregnancy rate in ART cycles. Obestatin may play a role in the pathophysiology of OHSS; this possibility should be confirmed in further research.

Glucocorticoid therapy in assisted reproduction

As glucocorticoids are well-known as important regulators of stress and the immune system, their function and clinical use have elicited substantial interest in the field of reproduction. In particular, the effect of glucocorticoid therapy on endometrial receptivity during assisted reproduction, including in vitro fertilization (IVF) cycles, has led to a great deal of interest and controversy. However, previous studies have not been able to provide consistent and reliable evidence due to their small, non-controlled designs and use of different criteria. Considering the potential risk of exposure to glucocorticoids for mothers and fetuses in early pregnancy, the use of glucocorticoids in IVF cycles should be carefully evaluated, including the balance between risk and benefit. To date, there is no conclusive evidence that the use of glucocorticoids improves the pregnancy rate in IVF cycles with unselected subjects, and a further investigation should be considered with a proper study design.

The impact of COVID-19 on human reproduction and directions for fertility treatment during the pandemic

Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly, resulting in a pandemic. The virus enters host cells through angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine subtype 2 (TMPRSS2). These enzymes are widely expressed in reproductive organs; hence, coronavirus disease 2019 (COVID-19) could also impact human reproduction. Current evidence suggests that sperm cells may provide an inadequate environment for the virus to penetrate and spread. Oocytes within antral follicles are surrounded by cumulus cells, which rarely express ACE2 and TMPRSS2. Thus, the possibility of transmission of the virus through sexual intercourse and assisted reproductive techniques seems unlikely. Early human embryos express coronavirus entry receptors and proteases, implying that human embryos are potentially vulnerable to SARS-CoV-2 in the early stages of development. Data on the expression of ACE2 and TMPRSS2 in the human endometrium are sparse. Moreover, it remains unclear whether SARS-CoV-2 directly affects the embryo and its implantation. A study of the effect of SARS-CoV-2 on pregnancy showed an increase in preterm delivery. Thus, vertical transmission of the virus from mother to fetus in the third trimester is possible, and further data on human reproduction are required to establish this possibility. Based on analyses of existing data, major organizations in this field have published guidelines on the treatment of infertility. Regarding these guidelines, despite the COVID-19 pandemic, reproductive treatment is crucial for the well-being of society and must be continued under suitable regulations and good standard laboratory practice protocols.