Reproduction & fertility最新文献

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Abstract: In normozoospermia, the albumin gradient filtration (AGF) and swim-up processing techniques are used to isolate spermatozoa with the highest biological parameters and specific sperm fertility indices (SSFI). In contrast, the highest number of sperm with the best motility rate, velocity, and SSFI, and the lowest DNA damage and nuclear fragmentation are isolated using the density gradient centrifugation (DGC) preparation technique in oligo-astheno-teratozoospermia (OAT) patients. The study aimed to evaluate the effect of DGC, AGF-1, AGF-2, and swim-up preparation techniques on biological parameters, including SSFI, chromatin integrity, and DNA fragmentation in patients with OAT and normozoospermia. One hundred men with normozoospermia and OAT participated in the study. Biological parameters (concentration, velocity, total motility, and normal morphology), SSFI (progressively motile sperm concentration-grade a (PMSCa), progressively motile sperm concentration-grade b (PMSCb), and sperm motility index, functional sperm concentration, motile sperm concentration), chromatin integrity, and DNA fragmentation were assessed before and after each processing method using SQA-V Gold sperm analyzer and specific staining, TUNEL, and COMET assays. In OAT patients, the highest number of sperm with the best velocity, motility, and SSFI was demonstrated in the DGC method. However, the AGF-2 technique was the most efficient method in normozoospermic patients. Sperm DNA damage significantly decreased following preparation with DGC, AGF-2, and swim-up techniques. Overall, the findings highlight that DGC is the most beneficial method for OAT patients, whereas AGF-2 and swim-up techniques are more suitable for normozoospermic individuals. These comparisons emphasize the need to tailor techniques according to patient-specific sperm profiles.

Lay summary: This study investigated how different laboratory methods for preparing sperm would help improve fertility treatment outcomes for men with fertility problems. We assessed four commonly used techniques to see how well they could choose the healthiest sperm from 100 men, both with and without fertility issues. We aimed to improve sperm quality by selecting those that move faster, have fewer abnormalities, and contain less damaged DNA. We revealed that men with poor sperm quality benefited most from a method that separates sperm based on how heavy they are. In contrast, men with normal sperm quality responded better to a different technique that uses a protein-based filter. All the methods tested were helpful in reducing sperm DNA damage, but two of them were more effective in preserving sperm health based on men's conditions. Our findings suggest that using the right sperm preparation method for each individual can increase the chances of success in fertility treatments.

Abstract: Melatonin is a key molecule in supporting pregnancy success in sheep, particularly under suboptimal conditions. In humans, melatonin is also known for its antioxidant properties. Additionally, it has recently been reported that melatonin differentially drives cell fate in normal vs altered trophoblast cells. Given that, we hypothesize that melatonin is a potential partner for trophoblasts to overcome a hypoxic environment during the early stage of pregnancy. Here, we explore the effect of melatonin on early trophoblast cell behaviour and its potential mitigating effect in CoCl2-induced hypoxia. Cell functionality and autophagy modulation were studied on ovine primary trophoblast cells (oTCs) 24 hours treated with 250µM melatonin with/without 200µM CoCl2. First, melatonin exerts its antioxidant effects by reducing H2O2 levels under hypoxic cellular conditions (P < 0.0001). CoCl2 suppressed cell proliferation and migration (P < 0.0001); however, melatonin supplementation partially restored oTCs functionality (P < 0.05). Melatonin-mediated cytoprotective effects are manifested even through the modulation of cell fate mechanisms, particularly autophagy and apoptosis. Increased protein expression of autophagic markers (BCLN1 and LC3BII/LC3BI ratio) in concomitance with a decreased phosphorylation of mTOR was observed in CoCl2-treated cells (P < 0.01), while a reduced rate of autophagy was detected following melatonin co-treatment (P < 0.01). Similarly, melatonin attenuates the CoCl2-induced increase in apoptosis when administered concurrently (5.5 vs 1.8%, P < 0.01). These findings suggest that melatonin promotes autophagy over apoptosis, indicating a shift toward cell survival mechanisms. Additionally, melatonin enhances cell functionality under hypoxia, suggesting the conceptus benefits from melatonin, particularly when it is forced to grow in a suboptimal environment.

Lay summary: Melatonin is known for its role in regulating reproduction in sheep; however, very little is known about the role it plays in the development of the placenta. Here, we take you through how melatonin helps the placental cells survive in a low-oxygen environment, a condition called hypoxia. In this environment, we found that melatonin helps the placental cells function and reduces their death rate by helping them recycle damaged parts to survive. Overall, our findings highlight melatonin as a powerful molecule playing a role in placental cells' survival and how they function under stressful conditions. Since hypoxia is a common cause of pregnancy complications, melatonin could be a valuable aid for both animals and humans. Indeed, this study shows that melatonin isn't just a sweet little pill-it's mighty and should only be used when truly needed.

Abstract: In this study, we aimed to uncover the perspectives of male childhood cancer survivors on parenthood, fertility preservation, and potential fertility restoration using their own cryopreserved testicular biopsy. We invited all young men eligible for this study, 27 male cancer survivors over the age of 16 who had undergone a testicular tissue biopsy in the past in Amsterdam, of whom five men (18.5% response rate) decided to participate. In semi-structured interviews, we discussed their views on parenthood, testicular cryopreservation, and potential fertility restoration, specifically through spermatogonial stem cell transplantation (SSCT). All data were pseudonymized before analysis via open coding using MAXQDA software. We found that all five participants (ages 17-24) had actively thought about family planning, and some expressed a very strong wish to experience parenthood, although they were aware of potential fertility issues related to their treatments. However, these participants reported that fertility issues had been minimally discussed at the late effects clinic during checkups, and they therefore had a limited understanding of the potential and restrictions of fertility restoration techniques such as SSCT. Overall, these participants displayed a high willingness to undertake additional steps to achieve biological parenthood and low levels of concern regarding the safety of SSCT. Autonomy and the opportunity of choice were determining factors in their underlying views. Perspectives and needs of these survivors, for whom a testicular biopsy was cryopreserved as a child, predominantly revolved around the importance of having autonomy over their fertility choices and being adequately informed to make those choices.

Lay summary: Treatments for childhood cancer may lead to infertility. To safeguard the fertility of young male cancer patients, a testicular biopsy can be frozen that contains spermatogonial stem cells (SSCs), the basis for spermatogenesis. This study focused on SSCT, a new fertility restoration treatment. Through interviews with five male survivors (aged 17-24), we explored their experiences and opinions on fertility preservation and restoration. In general, participants were happy with their parents' decision to freeze a biopsy. The freedom to choose was a key topic for them. They were willing to take the required steps to reach parenthood if desired. They had few concerns about the safety of SSCT but had questions about the chances of success. Their trust in science and healthcare was strong. However, in their experience, fertility was not sufficiently discussed during follow-up care. The results support doctors, former childhood cancer patients, and their parents concerning fertility after childhood cancer.

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Abstract: The etiology, epidemiology, and pathogenesis of many uterine diseases, including endometritis, cystic endometrial hyperplasia (CEH), and pyometra, remain poorly understood in canids, hindering the advancement of effective preventative therapeutics to ultimately improve fertility. The development of an in vitro endometrial cell culture system that mimics in vivo architecture, cellular morphology, and physiological responses would facilitate a greater understanding of the mechanisms of complex canine uterine diseases and reduce the need for in vivo research. Three-dimensional organoid cell cultures may provide an innovative approach for studying uterine pathologies in the bitch. Unlike traditional two-dimensional monolayer cell culture systems, organoids can be grown long-term while maintaining the structure, phenotype, and function of their organ of origin. Here, we report the generation and characterization of canine endometrial organoids via immunohistochemistry (IHC), transmission electron microscopy, and RT-qPCR, and demonstrate their responsiveness to exogenous steroid hormones mimicking the estrous cycle. Furthermore, gene expression of key inflammatory markers was upregulated in endometrial organoids derived from bitches with CEH compared to organoids derived from healthy tissue. Findings highlight canine endometrial organoids as a valuable model to study both normal uterine physiology and disease-related processes in dogs.

Lay summary: Organoids are cells that are grown three-dimensionally in the laboratory and retain similar functions to the organ from which the cells were collected. Organoids were used here to study female dog reproductive tissue without the need for live animals, which saves time and money and improves animal welfare. We developed a three-dimensional model of the dog uterus that responds to reproductive hormones and maintains its normal structure. In addition, we used diseased canine tissue to replicate CEH, a condition that affects pregnancy and can lead to the serious disease of pyometra, in which the uterus is infected and filled with pus. In future studies, this validated model can be used to study how CEH develops and to test new treatments for the disease.

Abstract: To more accurately classify human ovarian follicles by developing a novel methodology with three-dimensional visualisation using whole-mount immunolabelling and optical tissue clearing techniques. A whole-mount immunolabelling protocol combined with optical tissue clearing was applied to human ovarian tissue for three-dimensional follicle analysis. Key markers, including DAPI for nuclear staining, DDX4 for oocyte-specific labelling, and LAMININ for basal membranes, were used to visualise follicular structures. The tissues underwent a clearing process to enable confocal z-stack imaging to obtain detailed three-dimensional data. Ovarian cortical tissue from three paediatric patients (aged 9-12 years) who had not undergone chemotherapy treatment was collected. The tissue was dissected into small fragments and stained to identify viable follicles. Follicle and oocyte size, as well as granulosa cell size and type, were assessed across multiple dimensions (XY, XZ, YZ planes). Follicles were classified as primordial or transitional based on granulosa cell characteristics. Three-dimensional analysis across XY, XZ, and YZ planes revealed that 58% of follicles, initially classified as primordial using conventional two-dimensional methods, were misidentified as transitional due to the presence of cuboidal granulosa cells that were only detectable in multi-plane analysis. Moreover, three-dimensional analyses revealed significant differences in the number and size of cuboidal granulosa cells detected on transitional follicles. This study presents a novel whole-mount immunolabelling and optical tissue clearing methodology for accurate three-dimensional visualisation and classification of human ovarian follicles. This technique improves the accuracy of follicle staging and provides a valuable tool for future research into ovarian function, reproductive health, and conditions impacting follicle development.

Lay summary: In this study, we explored a new method for examining ovarian follicles - structures that contain the immature eggs - within human ovarian tissue. Traditional methods, which rely on two-dimensional imaging, can lead to mistakes in classifying the development of these follicles due to their spherical shape. To address this, we developed techniques to visualise the ovarian tissue in three dimensions. Using ovarian tissue from three patients, the tissue was processed using techniques called whole-mount immunolabelling (to detect structures) followed by optical clearing (to visualise the structures) and then analysed using microscopy. This enabled us to create detailed 3D images that showed the structures of the immature eggs and follicles across different planes of view. We discovered that conventional 2D assessments misclassified nearly 60% of the follicles, as certain developmental characteristics were only visible in the 3D images. This innovative approach marks the first time such detailed 3D

Abstract: The central goal of the following studies was to understand how FGF2, LIF, and IGF1, a cocktail called 'FLI', influence bovine embryo development by the degree of transcriptomic variation throughout preimplantation development. All embryos were produced in vitro with or without FLI supplementation at the beginning of culture. For each treatment, embryos were collected at the 4-6 cell, 9-16 cell, morula, or blastocyst stages, and RNA was isolated and sequenced at a depth of 50 million reads per sample. In the FLI group, at the 9-16 cell stage, there were seven upregulated and six downregulated differentially expressed genes (DEGs). At the morula stage, of the 1,856 DEGs, 580 were upregulated in FLI. Gene ontology analysis showed increased MAPK signaling, TGF-beta signaling, and Hippo signaling, which all help regulate cell adhesion, lineage commitment, and growth regulation in the developing embryo. In FLI blastocyst stage embryos, 199 upregulated and 545 downregulated DEGs revealed an increase in processes associated with interferon-gamma production and cell differentiation. Overall, FLI modulates many of the regulatory pathways in the developing embryo to drive increased cell survival, cell integrity, and overall embryo development.

Lay summary: This study investigated whether adding three supportive proteins - FGF2, LIF, and IGF1 (together called FLI) - could improve the development of cow embryos grown in vitro. In cattle breeding, embryos are often produced outside the body to enhance fertility and support genetic selection. However, many embryos fail to develop properly under laboratory conditions. To address this, researchers tested whether FLI could create a more favorable environment for early embryo growth. Although embryos grown with and without FLI appeared similar under the microscope, gene expression analysis revealed important differences. Embryos exposed to FLI showed signs of improved cell survival, healthier growth, and reduced stress. These molecular changes suggest that FLI may help embryos become more resilient to key procedures such as freezing and transfer. The findings support the use of FLI as a culture supplement to improve the efficiency and success of in vitro embryo production systems used in livestock reproductive biotechnologies.

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Abstract: Oocyte in vitro maturation (IVM) is an evolving component of assisted reproductive technology (ART) that offers a less invasive and cost-effective alternative to conventional controlled ovarian stimulation. It is particularly beneficial for patients at risk of ovarian hyperstimulation syndrome (OHSS), those with polycystic ovary syndrome (PCOS), and individuals requiring urgent fertility preservation. Despite these advantages, clinical uptake has remained limited owing to concerns about the developmental competence and quality of IVM-derived oocytes. To address this, we conducted a comprehensive literature search of PubMed, Embase, and Web of Science for articles published between January 2000 and June 2025, using combinations of keywords related to IVM, oocyte maturation, culture protocols, oocyte quality, and clinical outcomes. Recent progress in the field has led to the development of biphasic culture systems, pre-IVM priming strategies, and the incorporation of regulatory factors such as C-type natriuretic peptide (CNP) and oocyte-secreted factors, all of which have contributed to improved oocyte maturation and embryo development. Nonetheless, variability in outcomes persists due to differences in patient selection, stimulation protocols, and laboratory practice. Continued optimisation of IVM culture systems and a deeper understanding of oocyte maturation mechanisms will be essential for enhancing clinical efficacy. Future research should prioritise standardisation, patient-tailored protocols, and systematic long-term outcome data to support wider adoption of IVM. This review provides a comprehensive overview of recent advances and ongoing challenges in human oocyte IVM, offering perspectives on future directions for clinical translation and improved ART outcomes.

Lay summary: IVM is a fertility treatment that allows immature eggs to mature in the laboratory rather than within the body. This approach can be safer, simpler, and more affordable than traditional IVF, especially for women with polycystic ovary syndrome (PCOS), those at risk of ovarian hyperstimulation, or those who need to preserve their fertility quickly, such as cancer patients. Although IVM holds great promise, it is not yet widely used because its success rates are not as high as those of conventional methods. This review looks at the latest scientific progress to improve IVM, including better laboratory techniques, the use of natural hormones and growth factors, and new ways to support egg development outside the body. These advancements have helped improve the quality of eggs and embryos, but challenges remain. Differences in patient types, medications used, and lab practices can affect how well IVM works. More research is needed to make IVM more consistent and effective so it can become a routine fertility option for a broader population.

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Abstract: Ovarian tissue transplantation is vital for preserving fertility in female cancer survivors. Since the first human ovarian tissue transplantation in 2000 and the first live birth in 2004, it has received much more attention. However, the research scale, core research teams, and publication quality have not been systematically documented. This lack of foundational data hinders researchers' ability to assess the maturity and prevailing trends within the domain, potentially leading to duplicated efforts and suboptimal resource allocation. Our study addresses this gap by analyzing ovarian tissue transplantation research from 2000 to 2023 to map academic performance and collaboration networks. Key findings reveal Belgium and the USA as leading contributors, with robust international collaboration driving progress. The Université Catholique Louvain emerged as the most productive institution, while Dolmans M.M. stood out as a pivotal researcher. Human Reproduction ranked as the top journal for disseminating OTT advancements. Research trends highlight sustained focus on 'tissue cryopreservation', 'activation', and 'live-birth' through 2023, with disease indications shifting from 'breast cancer' and 'chemotherapy' toward 'infertility', 'leukemia', and 'premature ovarian failure'. This study offers crucial insights and understanding for collaborative work among researchers in the field of ovarian tissue transplantation, as well as recommendations for pioneering authors and journal submissions.

Lay summary: Ovarian tissue transplantation is the sole fertility preservation method for prepubertal girls and adult female patients whose anticancer therapy cannot be delayed. Since the first successful human live birth via ovarian tissue transplantation in 2004, this medical procedure has witnessed exponential growth, with more than 200 newborns worldwide having been delivered. This study presents an exhaustive bibliometric analysis that delineates the knowledge structure, authors' contributions, and research trends concerning ovarian tissue transplantation during the 21st century. We reveal that Belgium and the USA are in leading positions in terms of publications, citations, and academic influence. Keywords highlight the developmental trends in research types, ongoing foci, and disease indications for ovarian tissue transplantation. It offers crucial insights and understanding for collaborative work among researchers in the field of ovarian tissue transplantation, as well as recommendations for pioneering authors and journal submissions.