Field Of Reproductive Biology Research Articles

The role of kisspeptin in female and male reproduction

Kisspeptin is a neuropeptide responsible for controlling the synthesis of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH). The G-protein-coupled receptor 54/kisspeptin 1 receptor (GPR54/KISS1R) is involved in its action. The comprehension of kisspeptin and its actions represents a significant breakthrough in the field of reproductive biology. Kisspeptins play a crucial role in the development and optimal functioning of the reproductive system in both female and male. Additionally, it contributes to the onset of puberty, regulating feedback processes, and influencing sexual desire and arousal. It regulates a number of reproductive functions in women, including ovulation, lactation, ovarian development, follicle development, oocyte maturation, and pregnancy via the hypothalamic-pituitary-gonadal (HPG) axis. Spermatogenesis, sperm function, Leydig cells, and reproductive behaviour are all impacted by it in men. Infertility and polycystic ovarian syndrome (PCOS) are among the diseases linked to kisspeptin dysregulation, according to the research. For potential future use in diagnosing and treating problems, it may be helpful to understand the mechanisms behind kisspeptin's effects on the reproductive system. This review focuses on the regulatory function of kisspeptin on the HPG axis and the impact of kisspeptin on reproductive processes in both female and male.

Building methodological consensus to ensure rigor and reproducibility in zebrafish fertility research

The summary included in the text: Zebrafish are an increasingly popular model for studying the genetic and environmental factors that shape male and female fertility; however, the field currently lacks a standardized approach to fertility assessment. The current lack of consensus makes comparisons across studies more challenging and is an obstacle to reproducibility in the fields of reproductive biology and toxicology. Here, we review the diversity of spawning approaches used in zebrafish reproductive toxicology research to asses fertility and provide evidence that spawning parameters can result in meaningful differences in egg production and spawning success.

Viewing early life without labels: optical approaches for imaging the early embryo.

Embryo quality is an important determinant of successful implantation and a resultant live birth. Current clinical approaches for evaluating embryo quality rely on subjective morphology assessments or an invasive biopsy for genetic testing. However, both approaches can be inherently inaccurate and crucially, fail to improve the live birth rate following the transfer of in vitro produced embryos. Optical imaging offers a potential non-invasive and accurate avenue for assessing embryo viability. Recent advances in various label-free optical imaging approaches have garnered increased interest in the field of reproductive biology due to their ability to rapidly capture images at high-resolution, delivering both morphological and molecular information. This burgeoning field holds immense potential for further development, with profound implications for clinical translation. Here, our review aims to: 1) describe the principles of various imaging systems, distinguishing between approaches that capture morphological and molecular information, 2) highlight the recent application of these technologies in the field of reproductive biology, and 3) assess their respective merits and limitations concerning the capacity to evaluate embryo quality. Additionally, the review summarizes challenges in the translation of optical imaging systems into routine clinical practice, providing recommendations for their future development. Finally, we identify suitable imaging approaches for interrogating the mechanisms underpinning successful embryo development.

Network Pharmacology and In Vivo Validation to Explore the Potential Active Ingredients and Mechanisms of Ziyin Buyang Formula in Diminished Ovarian Reserve

The incidence rate of diminished ovarian reserve (DOR) is increasing, which is a difficult problem in the field of reproductive biology. The Ziyin Buyang Formula (ZYBYF), an empirical prescription for traditional Chinese medicine, is often used to improve the ovarian function of women with DOR. However, the underlying mechanism of this phenomenon remains unclear. This study was designed to identify the active components of ZYBYF and to further investigate the mechanism by which ZYBYF treats DOR through network pharmacological analysis and in vivo experiments. The network-based relationships between drug targets and disease-related proteins were screened, predicted, and constructed using a database. Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were conducted using R software. AutoDock Vina 1.1.2 was used to perform the molecular docking analysis. In vivo experimental verification was carried out by enzyme-linked immunosorbent assay, histological observation and reverse transcription-polymerase chain reaction. A total of 137 common targets were identified between ZYBYF and DOR. GO and KEGG enrichment analyses suggested that these compounds were associated with the PI3K/AKT signaling pathway and MAPK signaling pathway. Furthermore, the molecular docking analysis revealed that quercetin strongly binds to MAPK1, AKT1, MYC, EGFR, and BCL2; luteolin strongly binds to EGFR, AKT1, and MAPK1; and kaempferol strongly binds to AKT1 and BCL2. In addition, in vivo experiments confirmed that ZYBYF can regulate the serum sex hormone levels, improve the ovarian function of DOR model rats, downregulate the expression of Mapk1 and Mapk14, and increase the levels of Akt1, Egfr, Myc, and Bcl2. ZYBYF improved ovarian function in DOR model rats by regulating the MAPK and PI3K/AKT signaling pathways. This study provides objective evidence that supports the use of ZYBYF in the clinical application of DOR.

Advancing CRISPR technologies in reproductive biology

Clustered regularly interspaced short palindromic repeats (CRISPR) technology, a transformative tool for genetic modifications, gene therapy, and treating various genetic diseases, has recently garnered significant attention for its applications in reproductive biology. In this realm, researchers are focusing on addressing gynecological disorders, refining assisted reproductive methods, and conducting precise germ cell editing. The potential impact of CRISPR in these areas is monumental; however, several research gaps persist, demanding further investigation into the long-term effects, safety implications, and unintended consequences of its applications in reproductive biology. Refining the precision and specificity of CRISPR technology is a critical aspect that necessitates addressing challenges such as off-target effects and cytotoxicity. These considerations underscore the urgency for ongoing research efforts to ensure the efficacy and safety of CRISPR applications. In addition, the establishment of robust regulatory frameworks and oversight mechanisms specific to CRISPR in reproductive contexts is imperative to guarantee the responsible and ethical use of this powerful technology. This comprehensive review delves into the advantages of CRISPR over traditional gene editing methods, providing insights into its applications in embryos, pluripotent stem cells, and germline cells. It further explores the risks and limitations associated with CRISPR, including ethical concerns related to designer babies and eugenics. The article sheds light on the regulatory landscape governing new CRISPR applications in reproductive biology, emphasizing the continuous improvements in the efficiency and specificity of CRISPR technology. In contributing to the ongoing discourse, this review aims to inform and guide the responsible and effective application of CRISPR in the dynamic field of reproductive biology.

Heritable genome editing: ethical aspects of a developing domain.

In the past decade, scientific developments in human germline genome editing (GGE) have reinvigorated questions about research ethics, responsible innovation, and what it means to do good in the field of reproductive biology and medicine. In recent years, it has become part of the ethical debate on GGE whether categorical objections about (un)naturalness, dignity, respect for the gene pool as common heritage, are and should be supplemented by more pragmatic questions about safety, utility, efficacy, and potential 'misuse', which seem to become more dominant in the moral discussion. This mini-review summarizes the morally relevant aspects of the rapidly developing domain of GGE, focusing on reproductive applications and with special attention to the ethical questions pertaining to how this technology may affect the interests of those that come to be by means of it. While vital, this encompasses more than safety considerations. Taking this perspective, it will be crucial to engage with normative questions about how GGE maps on the importance of accommodating future parents' preference to have genetically related children, and how far we should go to facilitate this. Similarly, a comprehensive ethical debate about 'appropriate application' of GGE cannot shake off the more fundamental question about how notions like 'normalcy', 'quality of life', and 'disability' can be conceptualized. This is crucial in view of respecting persons whichever traits they have and in view of acceptable boundaries to parental responsibilities.

Vaginal Nanoformulations for the Management of Preterm Birth.

Preterm birth (PTB) is a leading cause of infant morbidity and mortality in the world. In 2020, 1 in 10 infants were born prematurely in the United States. The World Health Organization estimates that a total of 15 million infants are born prematurely every year. Current therapeutic interventions for PTB have had limited replicable success. Recent advancements in the field of nanomedicine have made it possible to utilize the vaginal administration route to effectively and locally deliver drugs to the female reproductive tract. Additionally, studies using murine models have provided important insights about the cervix as a gatekeeper for pregnancy and parturition. With these recent developments, the field of reproductive biology is on the cusp of a paradigm shift in the context of treating PTB. The present review focuses on the complexities associated with treating the condition and novel therapeutics that have produced promising results in preclinical studies.

Importance of Antioxidant Supplementation during In Vitro Maturation of Mammalian Oocytes.

Simple SummaryIn vitro embryo production (IVEP) is a technology that is widely used in the field of reproductive biology. The first and most important step of IVEP is termed in vitro maturation or IVM, in which the oocyte is allowed to mature in a synthetic medium under controlled laboratory settings. The quality of in vitro matured oocytes is still low compared to that of those matured inside an animal’s body. One of the key elements that was found to affect oocyte quality is the accumulation of large amounts of reactive oxygen species (ROS) within oocytes during IVM. The addition of antioxidants to oocyte IVM media is one of the most effective methods for preventing ROS accumulation. In this article, we highlight the latest events showing how ROS harms mammalian oocytes. We also discuss the possible impacts of antioxidant supplementation on the IVM rate and oocyte quality. The in vitro embryo production (IVEP) technique is widely used in the field of reproductive biology. In vitro maturation (IVM) is the first and most critical step of IVEP, during which, the oocyte is matured in an artificial maturation medium under strict laboratory conditions. Despite all of the progress in the field of IVEP, the quality of in vitro matured oocytes remains inferior to that of those matured in vivo. The accumulation of substantial amounts of reactive oxygen species (ROS) within oocytes during IVM has been regarded as one of the main factors altering oocyte quality. One of the most promising approaches to overcome ROS accumulation within oocytes is the supplementation of oocyte IVM medium with antioxidants. In this article, we discuss recent advancements depicting the adverse effects of ROS on mammalian oocytes. We also discuss the potential use of antioxidants and their effect on both oocyte quality and IVM rate.

The Effects of Male Seminal Fluid Proteins on Gut/Gonad Interactions in Drosophila.

Mating initiates broad physiological changes encompassing multiple organ systems in females. Elucidating the complex inter- and intra-organ signaling events that coordinate these physiological changes is an important goal in the field of reproductive biology. Further characterization of these complex molecular and physiological interactions is key to understanding how females meet the energetic demands of offspring production. Many recent studies of the fruit fly, Drosophila melanogaster, have described the mechanisms of post-mating changes within the female reproductive tract and digestive system. Additionally, other studies have described post-mating signaling crosstalk between these systems. Interestingly, male seminal fluid proteins have been linked to post-mating responses within the female reproductive tract and gut, and to signaling events between the two organ systems. However, information about the hormonal and neuronal signaling pathways underlying the post-mating signaling events within and between the reproductive tract and digestive systems that are triggered by seminal fluid proteins has yet to be combined into a single view. In this article, we summarize and integrate these studies into a single "network schematic" of the known signaling events within and between the reproductive and digestive systems downstream of male seminal fluid proteins. This synthesis also draws attention to the incomplete parts of these pathways, so that outstanding questions may be addressed in future studies.

PD36-10 THE MAMMALIAN REPRODUCTIVE GENETICS DATABASE, VERSION 2 (MRGDv2)

You have accessJournal of UrologyCME1 May 2022PD36-10 THE MAMMALIAN REPRODUCTIVE GENETICS DATABASE, VERSION 2 (MRGDv2) Ricardo Deras, Vivek Ramanathan, Xingquan Lu, Uma Ramamurthy, Martin Matzuk, Larry Lipshultz, and Thomas Garcia Ricardo DerasRicardo Deras More articles by this author , Vivek RamanathanVivek Ramanathan More articles by this author , Xingquan LuXingquan Lu More articles by this author , Uma RamamurthyUma Ramamurthy More articles by this author , Martin MatzukMartin Matzuk More articles by this author , Larry LipshultzLarry Lipshultz More articles by this author , and Thomas GarciaThomas Garcia More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002594.10AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The Mammalian Reproductive Genetics Database (MRGD; currently http://mrgd.org), established by Dr Robert E. Braun at the University of Washington in 1997, has had a long historical presence in the reproductive biology community as a research resource designed to disseminate highly relevant male and female reproductive tissue and cell gene expression data from many publications. Highly visited and highly cited, the website provided users a one-stop shop to quickly determine a gene expression profile for their gene or tissue of interest from an aggregate of many microarray data sources, all published between 2004 and 2008. Although of unquestionable significance in advancing the fields of male and female reproduction, with the advent of sequencing-based gene expression analyses, and the plethora of new published datasets available, the MRGD has been in dire need of presenting results from these newest advances in technology. METHODS: In the present work, we have established a new web portal, the Mammalian Reproductive Genetics Database, version 2 (MRGDv2). This new portal hosts interactive visualizations (customizable heatmaps and bar graphs) of male and female reproductive and non-reproductive tissue. Cell gene expression data from our recent reanalysis of 988 published human and mouse RNA-seq datasets was also present. RESULTS: We have generated a new and innovative database with a comprehensive assortment of additional human and mouse tissues and cells. The data is presented to users on a refreshed and modern web interface with most data hosted on the former MRGD re-included and referenced on the new website, with all gene IDs updated to the current version. Further, users are able to display the orthologous species' expression result side-by-side through one search. CONCLUSIONS: The former MRGD was highly utilized by biologists and researchers across the fields of reproductive biology and contraceptive development. It is anticipated that the MRGDv2 will be as impactful, if not more impactful, due the added datasets, functionality and features that have been added. With gene expression data at your fingertips, clinicians can make a more informed decision as to whether a mutated gene is likely to cause a reproductive phenotype-only, or cause disorders that extend to non-reproductive systems, and which systems are likely to be affected. Source of Funding: This work has been supported by the Male Contraceptive Initiative and the Eunice Kennedy Shriver National Institute of Child Health & Human Development grant R01HD095341 (to TXG) © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e636 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ricardo Deras More articles by this author Vivek Ramanathan More articles by this author Xingquan Lu More articles by this author Uma Ramamurthy More articles by this author Martin Matzuk More articles by this author Larry Lipshultz More articles by this author Thomas Garcia More articles by this author Expand All Advertisement PDF DownloadLoading ...

Transcriptomic analysis of cumulus cells shows altered pathways in patients with minimal and mild endometriosis

Endometriosis is a chronic inflammatory disorder that is highly associated with infertility. This association seems to be related to oocyte impairment, mainly in the initial stages of endometriosis (minimal and mild), where no distortions or adhesions are present. Nonetheless, invasive oocyte analyses are not routinely feasible; thus, indirect assessment of oocyte quality is highly desirable, and, in this context, cumulus cells (CCs) may be more suitable targets of analysis. CCs are crucial in oocyte development and could be used as an index of oocyte quality. Therefore, this prospective case–control study aimed to shed light on the infertility mechanisms of endometriosis I/II by analyzing the CCs’ mRNA transcription profile (women with endometriosis I/II, n = 9) compared to controls (women with tubal abnormalities or male factor, n = 9). The transcriptomic analyses of CCs from patients with minimal and mild endometriosis revealed 26 differentially expressed genes compared to the controls. The enrichment analysis evidenced some altered molecular processes: Cytokine-cytokine receptor interactions, Chemokine signaling, TNF signaling, NOD-like receptor signaling, NF-kappa B signaling, and inflammatory response. With the exception of CXCL12, all enriched genes were downregulated in CCs from patients with endometriosis. These findings provide a significant achievement in the field of reproductive biology, directing future studies to discover biomarkers of oocyte quality in endometriosis.

Roger Valentine Short

A veterinary surgeon whose intellectual curiosity and scientific rigour led to international acclaim and numerous honours and awards in the field of reproductive biology.

Altered insulin, leptin and ghrelin hormone levels and atypical estrous cycle lengths in two highly fertile mouse lines.

Mouse models of decreased fertility mainly support scientific knowledge in the field of reproductive biology. In this study, we changed the perspective, using Dummerstorf high-fertility mouse lines FL1 and FL2 selected for increased reproductive performances that doubled the amount of ovulated oocytes per cycle and the number of offspring per litter compared to an unselected control line (founder population, FZTDU, ctrl). After recent observations, both fertility lines seem to show a lower pregnancy rate compared to ctrl together with an atypical reproductive cycle. We analysed the estrous cycle of those mice, but also plasma levels of insulin, glucagon, leptin and ghrelin that, when irregular, may have an impact on the reproductive cycle length by modifying the GnRH release. We included females of another independent line (DU6P), selected from the same founder population but independently of fertility traits, as an additional model of decreased pregnancy rate. We aim to evaluate if do they use a similar mechanism associated in the regulation of the estrous cycle or implicated in altered pregnancy mechanism compared to control, because they show a similar situation as FL2 line does, even without an increase in fertility parameters. We speculate that FLs' estrous cycle undergoes changes during the selection period and aim to demonstrate that some hormonal dysfunctions link with altered reproductive cycle, dampened pregnancy rates and reduced first delivery rates mostly in FL2, but also with higher-fertility phenotype rather than lower in both FLs.

The history of assisted reproductive technologies: from prohibition to recognition

The birth of children after infertility treatment of married couples with the help of assisted reproductive technologies has become a reality after many years of basic research on the physiology of reproductive system, development of oocyte’s in vitro fertilization methods and cultivation of embryos at pre-implantation stages. Given the widespread use of assisted reproductive technologies in modern medical practice and the great interest of society to this problem, the aim of the study was to trace the main stages and key events of assisted reproductive technologies in the world and in Ukraine, as well as to highlight the activities of outstanding scientists of domestic and world science who were at the origins of the development of this area. The paper used historical methods to study and interpret the texts of primary sources and present scientific historical events. In addition, the current trends in assisted reproductive technologies are covered based on the results of our own, more than 30 years of experience in the field of reproductive biology and medicine, and the achievements of world scientists. As a result of the work, it has been shown that despite certain ethical and social biases, the discovery of individual predecessor scientists became the basis for the efforts of Robert Edwards and Patrick Steptoe to ensure birth of the world's first child, whose conception occurred outside the mother's body. There are also historical facts and unique photos from our own archive, which confirm the fact of the first successful oocyte in vitro fertilization and the birth of a child after the use of assisted reproductive technologies in Ukraine. Over the last 20 years, assisted reproductive technologies have continued to grow, addressing many other issues of reproductive potential preservation and infertility treatment. State of the art methods of assisted reproductive technologies include the development of cryopreservation method of gametes and embryos by vitrification, genetic screening of embryos in order to prevent the hereditary diseases transmission and embryo transfer with chromosomal abnormalities, the birth of a child “from three parents” in severe cases of mutations in the mitochondrial genome, etc.

Role of astaxanthin as an efficient antioxidant on the in vitro maturation and vitrification of porcine oocytes

As one of the most powerful natural antioxidants, astaxanthin (Ax) has begun to be applied to the field of reproductive biology. Here we used porcine oocyte as a model to explore how Ax improves the oocyte potential during in vitro maturation (IVM), and we also investigated the cytoprotective effects of Ax on the vitrified oocytes. Ax supplementation (final concentration of 2.5 μM) was subjected for immature oocytes during vitrification and subsequent IVM; fresh oocytes were also matured in vitro in the presence or absence of 2.5 μM Ax. Our results showed that Ax significantly increased the survival rate of vitrified oocytes, and promoted the blastocyst yield of both fresh and vitrified oocytes after parthenogenetic activation and somatic cell nuclear transfer. The oocytes treated with Ax displayed significantly lower reactive oxygen species generation and higher glutathione level. Vitrification of oocytes had no impact on caspase-3, cathepsin B and autophagic activities; Ax significantly decreased the cathepsin B activity in both fresh and vitrified oocytes. Moreover, the relative fluorescence intensity of lysosomes was significantly increased in vitrified oocytes, which was recovered by Ax treatment. The mitochondrial activity did not differ between fresh and vitrified oocytes, and was significantly enhanced in Ax-treated oocytes. Furthermore, Ax significantly restored the decreased expression of BMP15, ZAR1, POU5F1, GPX4 and LAMP2 genes in vitrified oocytes. Both fresh and vitrified oocytes treated with Ax showed significantly higher mRNA levels of GDF9, POU5F1, SOD2, NRF2 and ATG5. Taken together, this study provides new perspectives in understanding the mechanisms by which Ax improves the developmental competence of both fresh and vitrified porcine oocytes.

Neuronal activation modulates enhancer activity of genes for excitatory synaptogenesis through de novo DNA methylation.

Post-mitotic neurons do exhibit DNA methylation changes, contrary to the longstanding belief that the epigenetic pattern in terminally differentiated cells is essentially unchanged. While the mechanism and physiological significance of DNA demethylation in neurons have been extensively elucidated, the occurrence of de novo DNA methylation and its impacts have been much less investigated. In the present study, we showed that neuronal activation induces de novo DNA methylation at enhancer regions, which can repress target genes in primary cultured hippocampal neurons. The functional significance of this de novo DNA methylation was underpinned by the demonstration that inhibition of DNA methyltransferase (DNMT) activity decreased neuronal activity-induced excitatory synaptogenesis. Overexpression of WW and C2 domain-containing 1 (Wwc1), a representative target gene of de novo DNA methylation, could phenocopy this DNMT inhibition-induced decrease in synaptogenesis. We found that both DNMT1 and DNMT3a were required for neuronal activity-induced de novo DNA methylation of the Wwc1 enhancer. Taken together, we concluded that neuronal activity-induced de novo DNA methylation that affects gene expression has an impact on neuronal physiology that is comparable to that of DNA demethylation. Since the different requirements of DNMTs for germ cell and embryonic development are known, our findings also have considerable implications for future studies on epigenomics in the field of reproductive biology.

Immunohistological expression of cytochrome P450 1A2 (CYP1A2) in the ovarian follicles of prepubertal and pubertal rat

Cytochrome P450 1A2 (CYP1A2) is a member of the cytochrome P450 superfamily enzymes in mammals and plays a major role in metabolizing endogenous hormones in the liver. In recent days, CYP1A2 expression has been found in not only the liver but also other tissues including the pancreas and lung. However, little information is available regarding the expression of CYP1A2 in the ovary, in spite of the facts that the ovarian follicle growth and atresia are tightly associated with controls of endocrine hormonal networks. Therefore, the expression of CYP1A2 in the ovaries of prepubertal and pubertal rats was investigated to assess its expression pattern and puberty-related alteration. It was demonstrated that the expression level of CYP1A2 was significantly (p < 0.01) higher in the pubertal ovaries than prepubertal counterparts. At the ovarian follicle level in both groups, whereas CYP1A2 expression was less detectable in the primordial, primary and secondary follicles, the strongly positive expression of CYP1A2 was localized in the granulosa cell layers in the antral and pre-ovulatory follicles. However, the ratio of CYP1A2-positive ovarian follicle was significantly (p < 0.01) higher in the ovary of pubertal group (73.1 ± 3.1%) than prepubertal one (41.0 ± 10.5%). During the Immunofluorescence, expression of CYP1A2 was mainly localized in Fas-positive follicles, indicating the atretic follicles. In conclusion, these results suggested that CYP1A2 expression was mainly localized at the atretic follicular cells and affected by the onset of puberty. Further study is still necessary but we hypothesize that CYP1A2 expresses in the atretic follicles to metabolize residue of the reproductive hormones. These findings may have important implications for the fields of reproductive biology of animals.

Sirtuins in female meiosis and in reproductive longevity.

Transmission of genetic material through high-quality gametes to progeny requires accurate homologous chromosome recombination and segregation during meiosis. A failure to accomplish these processes can have major consequences in reproductive health, including infertility, and development disorders in offspring. Sirtuins, a family of NAD+ -dependent protein deacetylases and ADP-ribosyltransferases, play key roles in genome maintenance, metabolism, and aging. In recent years, Sirtuins have emerged as regulators of several reproductive processes and interventions aiming to target Sirtuin activity are of great interest in the reproductive biology field. Sirtuins are pivotal to protect germ cells against oxidative stress, a major determinant influencing ovarian aging and the quality of gametes. Sirtuins also safeguard the integrity of the genome through epigenetic programs required for regulating gene repression, DNA repair, and chromosome segregation, among others. Although these functions are relatively well characterized in many somatic tissues, how they contribute to reproductive functions is not well understood. This review summarizes our current knowledge on the role of Sirtuins in female reproductive systems and discusses the underlying molecular pathways. In addition, we highlight the importance of Sirtuins as antiaging factors in the ovary and summarize current preclinical efforts to identify treatments to extend female reproductive longevity.

In memoriam: Paolo Sassone-Corsi.

In memoriam: Paolo Sassone-Corsi.

Brilliant cresyl blue enhanced optoacoustic imaging enables non-destructive imaging of mammalian ovarian follicles for artificial reproduction.

In the field of reproductive biology, there is a strong need for a suitable tool capable of non-destructive evaluation of oocyte viability and function. We studied the application of brilliant cresyl blue (BCB) as an intra-vital exogenous contrast agent using multispectral optoacoustic tomography (MSOT) for visualization of porcine ovarian follicles. The technique provided excellent molecular sensitivity, enabling the selection of competent oocytes without disrupting the follicles. We further conducted in vitro embryo culture, molecular analysis (real-time and reverse transcriptase polymerase chain reaction) and DNA fragmentation analysis to comprehensively establish the safety of BCB-enhanced MSOT imaging in monitoring oocyte viability. Overall, the experimental results suggest that the method offers a significant advance in the use of contrast agents and molecular imaging for reproductive studies. Our technique improves the accurate prediction of ovarian reserve significantly and, once standardized for in vivo imaging, could provide an effective tool for clinical infertility management.