Sodium thiosulfate does not protect ovarian reserve from cisplatin-induced gonadotoxicity†.

Cisplatin, a platinum-containing alkylating agent, is used in the treatment of various tumors owing to its potent antitumor activity. However, it causes permanent and adverse effects, particularly hearing loss and depletion of ovarian reserve. Until recently, there were no clinically available protective agents to mitigate the adverse side effects of cisplatin-induced cytotoxicity. In 2022, sodium thiosulfate (STS) was approved by the Food and Drug Administration for mitigating hearing loss in children and adolescents undergoing cisplatin treatment. Consequently, our investigation aimed to determine if STS could protect ovarian reserve against cisplatin-induced gonadotoxicity. In an ex vivo culture, the cisplatin-only group exhibited a loss of primordial follicles, while post-STS administration after cisplatin exposure effectively protected primordial follicles. However, when post-STS was administrated either 6 or 4 h after cisplatin exposure, it did not confer protection against cisplatin-induced gonadotoxicity in postnatal day 7 or adolescent mouse models. Immunofluorescence assays using γH2AX and cPARP revealed that oocytes within primordial follicles exhibited DNA damage after cisplatin exposure, irrespective of post-STS administration. This underscores the rapid and heightened sensitivity of oocytes to gonadotoxicity. In addition, oocytes demonstrated an increased expression of pCHK2 rather than pERK, suggesting that the pathway leading to oocyte death differs from the pathway observed in the inner ear cell death following cisplatin exposure. These results imply that while the administration of STS after cisplatin is highly beneficial in preventing hearing loss, it does not confer a protective effect on the ovaries in mouse models.

Overview of the Multispecies Ovary Tissue Histology Electronic Repository†.

The Multispecies Ovary Tissue Histology Electronic Repository (MOTHER) is a publicly accessible repository of ovary histology images. MOTHER includes hundreds of images from nonhuman primates, as well as ovary histology images from an expanding range of other species. Along with an image, MOTHER provides metadata about the image, and for selected species, follicle identification annotations. Ongoing work includes assisting scientists with contributing their histology images, creation of manual and automated (via machine learning) processing pipelines to identify and count ovarian follicles in different stages of development, and the incorporation of that data into the MOTHER database (MOTHER-DB). MOTHER will be a critical data repository storing and disseminating high-value histology images that are essential for research into ovarian function, fertility, and intra-species variability.

Anatomic nomenclature and 3-dimensional regional model of the human ovary: call for a new paradigm.

The ovaries are the female gonads that are crucial for reproduction, steroid production, and overall health. Historically, the ovary was broadly divided into regions defined as the cortex, medulla, and hilum. This current nomenclature lacks specificity and fails to consider the significant anatomic variations in the ovary. Recent technological advances in imaging modalities and high-resolution omic analyses have brought about the need for revision of the existing definitions, which will facilitate the integration of generated data and enable the characterization of organ subanatomy and function at the cellular level. The creation of these high-resolution multimodal maps of the ovary will enhance collaboration and communication among disciplines and between clinicians and researchers. Beginning in March 2021, the Pediatric and Adolescent Gynecology Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development invited subject-matter experts to participate in a series of workshops and meetings to standardize ovarian nomenclature and define the organ's features. The goal was to develop a spatially defined and semantically consistent terminology of the ovary to support collaborative, team science-based endeavors aimed at generating reference atlases of the human ovary. The group recommended a standardized, 3-dimensional description of the ovary and an ontological approach to the subanatomy of the ovary and definition of follicles. This new greater precision in nomenclature and mapping will better reflect the ovary's heterogeneous composition and function, support the standardization of tissue collection, facilitate functional analyses, and enable clinical and research collaborations. The conceptualization process and outcomes of the effort, which spanned the better part of 2021 and early 2022, are introduced in this article. The institute and the workshop participants encourage researchers and clinicians to adopt the new systems in their everyday work to advance the overarching goal of improving human reproductive health.

Oocyte quality following in vitro follicle development†.

In vitro follicle development (IVFD) is an adequate model to obtain basic knowledge of folliculogenesis and provides a tool for ovarian toxicity screening. IVFD yielding competent oocytes may also offer an option for fertility and species preservation. To promote follicle growth and oocyte maturation in vitro, various culture systems are utilized for IVFD in rodents, domestic animals, wild animals, nonhuman primates, and humans. Follicle culture conditions have been improved by optimizing gonadotropin levels, regulatory factors, nutrient supplements, oxygen concentration, and culture matrices. This review summarizes quality assessment of oocytes generated from in vitro-developed antral follicles from the preantral stage, including oocyte epigenetic and genetic profile, cytoplasmic and nuclear maturation, preimplantation embryonic development following in vitro fertilization, as well as pregnancy and live offspring after embryo transfer. The limitations of oocyte quality evaluation following IVFD and the gaps in our knowledge of IVFD to support proper oocyte development are also discussed. The information may advance our understanding of the requirements for IVFD, with a goal of producing competent oocytes with genetic integrity to sustain embryonic development resulting in healthy offspring.

Development of sheep secondary follicles and preservation of aromatase and metalloproteinases 2 and 9 after vitrification and in vitro culture.

The cryopreservation of secondary follicles (SF) is a promising alternative to preserve the reproductive potential both in humans and animals in situations in which the transplantation of ovarian tissue is not possible. The objective of the present study was cryopreserved SF isolated sheep. Beyond follicular morphology, viability and development, we investigated proteins related to steroidogenic function and basement membrane remodeling [metalloproteinases 2 (MMP-2) and 9 (MMP-9)] in fresh SF (FSF) and vitrified SF (VSF) followed by in vitro culture for 6 (D6) or 12 days (D12). The percentage of intact follicles, follicular and oocyte diameter of the VSF were lower than FSF on both days of culture (P < 0.05). The VSF viability was statistically reduced from D6 (95.5%) to D12 (77.3%) but did not differ from the FSF on both days (D6:96.2% to D12:86.5%). Antrum formation in the VSF (D6: 59.13%; D12: 79.56%) was significantly lower than the FSF (D6: 79.61%; D12: 92.23%). However, an increase in this percentage was observed from D6 to D12 in both groups. Aromatase showed stronger labeling on FSF D6 and VSF D12 compared to other treatments (P < 0.05). MMP-2 showed a similar pattern of labeling in FSF D6 and VSF D12, similarly to that observed in FSF D12 and VSF D6. MMP-9 was similar in FSF and VSF cultivated for 6 and 12 days. In conclusion, VSF are able to grow and develop during 12 days of in vitro culture and showed evidence of preservation of steroidogenic function and remodeling of the basement membrane.

Sphingosine-1-phosphate and its mimetic FTY720 do not protect against radiation-induced ovarian fibrosis in the nonhuman primate†.

Oocytes are highly radiosensitive, so agents that prevent radiation-induced ovarian follicle destruction are important fertility preservation strategies. A previous study in rhesus macaques demonstrated that ovarian treatment with antiapoptotic agents, sphingosine-1-phosphate (S1P) and FTY720, its long-acting mimetic, preserved follicles following a single dose of 15 Gy X-ray radiation, and live offspring were obtained from FTY720-treated animals. However, it is unknown whether these antiapoptotic agents also protected the ovarian stroma from late effects of radiation, including vascular damage and fibrosis. Using ovarian histological sections from this study, we evaluated the vasculature and extracellular matrix in the following cohorts: vehicle + sham irradiation, vehicle + irradiation (OXI), S1P + irradiation (S1P), and FTY720 + irradiation (FTY720). One ovary from each animal was harvested prior to radiation whereas the contralateral ovary was harvested 10 months post-treatment. We assessed vasculature by immunohistochemistry with a PECAM1 antibody, hyaluronan by a hyaluronan binding protein assay, and collagen by picrosirius red and Masson's trichrome staining. Disorganized vessels were observed in the medulla in the OXI and S1P cohorts relative to the sham, but the vasculature in the FTY720 cohort appeared intact, which may partially explain fertoprotection. There were no differences in the hyaluronan matrix among the cohorts, but there was thickening of the tunica albuginea and fibrosis in the OXI cohort relative to the sham, which was not mitigated by either S1P or FTY720 treatment. Thus, the fertoprotective properties of S1P and FTY720 may be limited given their inability to protect the ovarian stroma against the late effects of radiation-induced fibrosis.

Impacts of different synthetic polymers on vitrification of ovarian tissue.

Type and concentration of cryoprotective agents (CPAs) are important factors which influence the likelihood of a successful ovarian tissue vitrification outcome. In an attempt to address this factor, the present study was conducted to evaluate the impacts of different synthetic polymers (Supercool X-1000, Supercool Z-1000 and PVP K-12) on vitrification of bovine ovarian tissue. From each ovarian pair, fragments were recovered and immediately fixed for analysis (fresh control) or submitted to vitrification, either or not followed by in vitro culture for one or five days. Vitrification was performed using the ovarian tissue cryosystem (OTC) system. The ovarian tissues were intended for histological and viability analysis [Reactive oxygen species (ROS) production and degenerate cells assay (Ethidium homodimer-1)], as well as immunolocalization of AQP3 and AQP9 were measured. The results showed that during almost all the periods after warming, in treatment groups which contain polymer (X-1000, Z-1000 and PVP), the percentage of morphologically normal follicles was the highest in the X-1000 samples. Furthermore, post-thawed X-1000 group revealed stronger labeling for AQP9 in primordial and transitional follicles, when compared with others. However, morphology after cryopreservation did not correlate with follicle viability and function where the levels of degeneration and tissue damage of PVP K-12 group were lower in comparison with X-1000 group and only in PVP K-12 group, ROS level was similar to that of the fresh control group. We believe that in addition to permeating CPAs, the addition of one (Supercool X-1000) or maybe a combination (Supercool X-1000 and PVP K-12) of non-permeating polymers could be useful to improve the outcome for vitrified bovine ovarian tissue.

Can peri-ovulatory putrescine supplementation improve egg quality in older infertile women?

The aging-related decline in fertility is an increasingly pressing medical and economic issue in modern society where women are delaying family building. Increasingly sophisticated, costly, and often increasingly invasive, assisted reproductive clinical protocols and laboratory technologies (ART) have helped many older women achieve their reproductive goals. Current ART procedures have not been able to address the fundamental problem of oocyte aging, the increased rate of egg aneuploidy, and the decline of developmental potential of the eggs. Oocyte maturation, which is triggered by luteinizing hormone (LH) in vivo or by injection of human chorionic gonadotropin (hCG) in an in vitro fertilization (IVF) clinic, is the critical stage at which the majority of egg aneuploidies arise and when much of an egg's developmental potential is established. Our proposed strategy focuses on improving egg quality in older women by restoring a robust oocyte maturation process. We have identified putrescine deficiency as one of the causes of poor egg quality in an aged mouse model. Putrescine is a biogenic polyamine naturally produced in peri-ovulatory ovaries. Peri-ovulatory putrescine supplementation has reduced egg aneuploidy, improved embryo quality, and reduced miscarriage rates in aged mice. In this paper, we review the literature on putrescine, its occurrence and physiology in living organisms, and its unique role in oocyte maturation. Preliminary human data demonstrates that there is a maternal aging-related deficiency in ovarian ornithine decarboxylase (ODC), the enzyme responsible for putrescine production. We argue that peri-ovulatory putrescine supplementation holds great promise as a natural and effective therapy for infertility in women of advanced maternal age, applicable in natural conception and in combination with current ART therapies.

The National Physicians Cooperative: transforming fertility management in the cancer setting and beyond.

Once unimaginable, fertility management is now a nationally established part of cancer care in institutions, from academic centers to community hospitals to private practices. Over the last two decades, advances in medicine and reproductive science have made it possible for men, women and children to be connected with an oncofertility specialist or offered fertility preservation soon after a cancer diagnosis. The Oncofertility Consortium's National Physicians Cooperative is a large-scale effort to engage physicians across disciplines - oncology, urology, obstetrics and gynecology, reproductive endocrinology, and behavioral health - in clinical and research activities to enable significant progress in providing fertility preservation options to children and adults. Here, we review the structure and function of the National Physicians Cooperative and identify next steps.

Development of macaque secondary follicles exposed to neutral red prior to 3-dimensional culture.

PURPOSE: Neutral red (NR) may assist identification of preantral follicles in pieces of cortical tissue prior to cryopreservation in cancer patients requesting fertility preservation. This study is the first to analyze this effect by follicle growth rate after long-term culture in primates. METHODS: Ovarian cortex was obtained from adult rhesus macaques, was cut into fragments, and was incubated with NR. Secondary follicles were readily visualized following NR staining and then were encapsulated into alginate beads and cultured individually for 4 weeks in αMEM media supplemented with 10 ng/ml FSH at 5% O2. RESULTS: The survival rates of secondary follicles during culture were similar between those derived from control tissue (71 ± 13%) and those treated with NR (68 ± 9%). The proportion of surviving follicles that formed an antrum were also similar in both groups (70 ± 17% control; 48 ± 24% NR-treated). Follicle diameters were not different between control follicles (184 ± 5µm) and those stained with NR (181 ± 7 µm) on the day of isolation. The percentages of surviving follicles within three cohorts based on their diameters at week 4 of culture were similar between the control group and NR-stained tissue group, fast-grow follicles (24 ± 6% vs. 13 ± 10%), slow-grow follicles (66 ± 5% vs. 60 ± 9%), or no-grow (10 ± 9% vs. 27 ± 6%), respectively. There were no differences in follicle diameters between groups during the culture period. Pre-exposure of secondary follicles to NR diminished their capacity to produce both estradiol and androstenedione by week 4 of culture, when follicles are exhibiting an antrum. Inhibitory effects of NR on steroid production by slow-grow follicles was less pronounced. CONCLUSIONS: NR does not affect secondary follicle survival, growth, and antrum formation during long-term culture, but steroid hormone production by fast-grow follicles is compromised. NR can be used as a non-invasive tool for in situ identification of viable secondary follicles in ovarian cortex before tissue cryopreservation without affecting follicle survival and growth in vitro. Whether maturation or developmental competence of oocytes derived from antral follicles in 3D culture that were previously isolated from NR-stained tissue is normal or compromised remains to be determined. Likewise, the functional consequences of pre-exposure to NR prior to ovarian cortical tissue cryopreservation and transplantation are unknown.

New Approaches in Cancer Biology Can Inform the Biology Curriculum.

Students tend to be very interested in medical issues that affect them and their friends and family. Using cancer as a hook, the ART of Reproductive Medicine: Oncofertility curriculum (free, online, and NIH sponsored) has been developed to supplement the teaching of basic biological concepts and to connect biology and biomedical research. This approach allows integration of up-to-date information on cancer and cancer treatment, cell division, male and female reproductive anatomy and physiology, cryopreservation, fertility preservation, stem cells, ethics, and epigenetics into an existing biology curriculum. Many of the topics covered in the curriculum relate to other scientific disciplines, such as the latest developments in stem cell research including tissue bioengineering and gene therapy for inherited mitochondrial disease, how epigenetics occurs chemically to affect gene expression or suppression and how it can be passed down through the generations, and the variety of biomedical careers students could pursue. The labs are designed to be open-ended and inquiry-based, and extensions to the experiments are provided so that students can explore questions further. Case studies and ethical dilemmas are provided to encourage thoughtful discussion. In addition, each chapter of the curriculum includes links to scientific papers, additional resources on each topic, and NGSS alignment.

Characterization of FOXO1, 3 and 4 transcription factors in ovaries of fetal, prepubertal and adult rhesus macaques.

The phosphoinositide 3-kinase/AKT (protein kinase B) signaling pathway negatively regulates follicle activation via the forkhead box O (FOXO) transcription factor in rodents. FOXO3 knockout mice exhibit global activation of primordial follicles leading to early depletion of ovarian follicles and subsequent infertility. Whether a similar mechanism for follicle activation exists in the primate ovary is unclear. In the current study, protein localization of FOXO1, 3, and 4 as well as their upstream regulator, AKT/p-AKT, was examined in rhesus macaque ovaries of three developmental stages: fetal, prepubertal, and adult. FOXO1 protein is expressed in granulosa cells of fetal, prepubertal, and adult ovaries. FOXO3 is distributed sparsely in the mitotically active germ cells, but its expression decreases following follicle formation in the macaque fetal ovary. In addition, FOXO3 is seldom with interanimal variation in the prepubertal ovary and is absent in the adult ovary. FOXO4 is nondetectable in fetal ovaries, although it is expressed in some theca cells of antral follicles and some stromal cells in prepubertal and adult ovaries. Our results suggest that the regulation and/or function of FOXO3 in the primate primordial follicle may differ than that of the rodent. Nevertheless, AKT/p-AKT is expressed in macaque primordial oocytes, suggesting that similar upstream events but different downstream effects may regulate primordial follicle activation in nonhuman primates compared to rodents. Elucidation of the mechanism responsible for follicle activation in primates will be crucial for understanding primary ovarian insufficiency, improving female fertility, and applying techniques for in vitro maturation of follicles for fertility preservation in cancer survivors.

Good manufacturing practice requirements for the production of tissue vitrification and warming and recovery kits for clinical research.

Products that are manufactured for use in a clinical trial, with the intent of gaining US Food and Drug Administration (FDA) approval for clinical use, must be produced under an FDA approved investigational new drug (IND) application. We describe work done toward generating reliable methodology and materials for preserving ovarian cortical tissue through a vitrification kit and reviving this tissue through a warming and recovery kit. We have described the critical steps, procedures, and environments for manufacturing products with the intent of submitting an IND. The main objective was to establish an easy-to-use kit that would ensure standardized procedures for quality tissue preservation and recovery across the 117 Oncofertility Consortium sites around the globe. These kits were developed by breaking down the components and steps of a research protocol and recombining them in a way that considers component stability and use in a clinical setting. The kits were manufactured utilizing current good manufacturing practice (cGMP) requirements and environment, along with current good laboratory practices (cGLP) techniques. Components of the kit were tested for sterility and endotoxicity, and morphological endpoint release criteria were established. We worked with the intended down-stream users of these kits for development of the kit instructions. Our intention is to test these initial kits, developed and manufactured here, for submission of an IND and to begin clinical testing for preserving the ovarian tissue that may be used for future restoration of fertility and/or hormone function in women who have gonadal dysgenesis from gonadotoxic treatment regimens or disease.

Subcutaneous ovarian tissue transplantation in nonhuman primates: duration of endocrine function and normalcy of subsequent offspring as demonstrated by reproductive competence, oocyte production, and telomere length.

PURPOSE: The main purposes of the study were to investigate the endocrine function of ovarian tissue transplanted to heterotopic subcutaneous sites and the reproductive competence and telomere length of a nonhuman primate originating from transplanted tissue. METHODS: Ovarian cortex pieces were transplanted into the original rhesus macaques in the arm subcutaneously, in the abdomen next to muscles, or in the kidney. Serum estradiol (E2) and progesterone (P4) concentrations were measured weekly for up to 8 years following tissue transplantation. A monkey derived from an oocyte in transplanted ovarian tissue entered time-mated breeding and underwent controlled ovarian stimulation. Pregnancy and offspring were evaluated. Telomere lengths and oocytes obtained following controlled ovarian stimulation were assessed. RESULTS: Monkeys with transplants in the arm and abdomen had cyclic E2 of 100 pg/ml, while an animal with arm transplants had E2 of 50 pg/ml. One monkey with transplants in the abdomen and kidney had ovulatory cycles for 3 years. A monkey derived from an oocyte in transplanted tissue conceived and had a normal gestation until intrapartum fetal demise. She conceived again and delivered a healthy offspring at term. Controlled ovarian stimulations of this monkey yielded mature oocytes comparable to controls. Her telomere length was long relative to controls. CONCLUSIONS: Heterotopic ovarian tissue transplants yielded long-term endocrine function in macaques. A monkey derived from an oocyte in transplanted tissue was reproductively competent. Her telomere length did not show epigenetically induced premature cellular aging. Ovarian tissue transplantation to heterotopic sites for fertility preservation should move forward cautiously, yet optimistically.

Reproductive Science for High School Students: A Shared Curriculum Model to Enhance Student Success.

The lack of a national reproductive biology curriculum leads to critical knowledge gaps in today's high school students' comprehensive understanding of human biology. The Oncofertility Consortium developed curricula that address the basic and clinical aspects of reproductive biology. Launching this academy and creating easy-to-disseminate learning modules allowed other universities to implement similar programs across the country. The expansion of this informal, extracurricular academy on reproductive health from Northwestern University to the University of California, San Diego, Oregon Health & Science University, and the University of Pennsylvania magnifies the scope of scientific learning to students who might not otherwise be exposed to this important information. To assess the experience gained from this curriculum, we polled alumni from the four centers. Data were collected anonymously from de-identified users who elected to self-report on their experiences in their respective reproductive science academy. The alumni survey asked participants to report on their current academic standing, past experiences in the academy, and future academic and career goals. The results of this national survey suggest the national oncofertility academies had a lasting impact on participants and may have contributed to student persistence in scientific learning.

Ovarian tissue transport to expand access to fertility preservation: from animals to clinical practice.

Primordial follicles dictate a female's reproductive life span and therefore are central to fertility preservation for both endangered species and individuals with fertility-threatening conditions. Ovarian tissue containing primordial follicles can be cryopreserved and later thawed and transplanted back into individuals to restore both endocrine function and fertility. Importantly, increasing numbers of human live births have been reported following ovarian tissue cryopreservation and transplantation. A current limitation of this technology is patient access to sites that are approved or equipped to process and cryopreserve ovarian tissue - especially in larger countries or low resource settings. Here, we review empirical evidence from both animal models and human studies that suggest that ovarian tissue can be transported at cold temperatures for several hours while still maintaining the integrity and reproductive potential of the primordial follicles within the tissue. In fact, several human live births have been reported in European countries using tissue that was transported at cold temperatures for up to 20 h before cryopreservation and transplantation. Ovarian tissue transport, if implemented widely in clinical practice, could therefore expand both patient and provider access to emerging fertility preservation options.

MOTHER-DB: A Database for Sharing Nonhuman Ovarian Histology Images.

The goal of the Multispecies Ovary Tissue Histology Electronic Repository (MOTHER) project is to establish a collection of nonhuman ovary histology images for multiple species as a resource for researchers and educators. An important component of sharing scientific data is the inclusion of the contextual metadata that describes the data. MOTHER extends the Ecological Metadata Language (EML) for documenting research data, leveraging its data provenance and usage license with the inclusion of metadata for ovary histology images. The design of the MOTHER metadata includes information on the donor animal, including reproductive cycle status, the slide and its preparation. MOTHER also extends the ezEML tool, called ezEML+MOTHER, for the specification of the metadata. The design of the MOTHER database (MOTHERDB) captures the metadata about the histology images, providing a searchable resource for discovering relevant images. MOTHER also defines a curation process for the ingestion of a collection of images and its metadata, verifying the validity of the metadata before its inclusion in the MOTHER collection. A Web search provides the ability to identify relevant images based on various characteristics in the metadata itself, such as genus and species, using filters.