Adipose-derived stem cells improved mouse ovary function after chemotherapy-induced ovary failure

Urinary bladder matrix scaffold improves the impact of adipose-mesenchymal stem cells on the function and structure of transplanted rat ovaries

Ovarian transplantation presents significant advantages for the preservation of female fertility. Nonetheless, a substantial number of follicles are apoptosis during the process of ovarian tissue transplantation as a result of ischemic conditions. This study aimed to assess whether adipose-derived mesenchymal stem cells combined with urinary bladder matrix (ADSC/UBM) confer a greater therapeutic benefit compared to ADSCs alone. To achieve this, ADSC/UBM was applied during the autotransplantation of rat ovaries. Thirty rats were divided into five sets of six: the untreated control group (Normal), the oophorectomy group, the autograft group, the autograft + ADSCs group (ADSC), and the autograft + ADSC/UBM group (ADSC/UBM). After transplantation, the number of follicles in the ADSC/UBM group was significantly higher than that in the autograft group. Angiogenesis was enhanced following ADSC/UBM transplantation. Follicle-stimulating hormone (FSH) levels were significantly lower, and Anti-Müllerian hormone (AMH) levels were significantly higher in rats in the ADSC/UBM group than in the Autograft group. The apoptosis rate in the ADSC/UBM group decreased. The estrous cycle in the ADSC/UBM group recovered more quickly than the ADSC group. The data indicate that UBM improves ADSC retention in graft ovaries and aids in permanently restoring ovarian function, making ADSC/UBM a promising option for ovarian transplantation.

Application of Mesenchymal Stem Cells in Female Infertility Treatment: Protocols and Preliminary Results

Infertility is a global phenomenon that impacts people of both the male and the female sex; it is related to multiple factors affecting an individual's overall systemic health. Recently, investigators have been using mesenchymal stem cell (MSC) therapy for female-fertility-related disorders such as polycystic ovarian syndrome (PCOS), premature ovarian failure (POF), endometriosis, preeclampsia, and Asherman syndrome (AS). Studies have shown promising results, indicating that MSCs can enhance ovarian function and restore fertility for affected individuals. Due to their regenerative effects and their participation in several paracrine pathways, MSCs can improve the fertility outcome. However, their beneficial effects are dependent on the methodologies and materials used from isolation to reimplantation. In this review, we provide an overview of the protocols and methods used in applications of MSCs. Moreover, we summarize the findings of published preclinical studies on infertility treatments and discuss the multiple properties of these studies, depending on the isolation source of the MSCs used.

Stem cell-based therapeutic potential in female ovarian aging and infertility

Premature ovarian insufficiency (POI) is defined as onset of menopause characterized by amenorrhea, hypergonadotropism, and hypoestrogenism, before the age of 40 years. The POI is increasing, which seriously affects the quality of patients' life. Due to its diversity of pathogenic factors, complex pathogenesis and limited treatment methods, the search for finding effective treatment of POI has become a hotspot. Stem cells are characterized by the ability of self-renewal and differentiation and play an important role in the regeneration of injured tissues, which is therapy is expected to be used in the treatment of POI. The aim of this review is to summarize the pathogenic mechanisms and the research progress of POI treatment with stem cells from different sources.

Tissue engineering and stem cell-based therapeutic strategies for premature ovarian insufficiency

Premature ovarian insufficiency (POI), also known as premature ovarian failure (POF), is a complex endocrine disease that commonly affects women under the age of 40. It is characterized by the cessation of ovarian function before the age of 40, leading to infertility and hormonal imbalances. The currently available treatment options for POI are limited and often ineffective. Tissue engineering and stem cell-based therapeutic strategies have emerged as promising approaches to restore ovarian function and improve the quality of life for women affected by POI. This review aims to provide a comprehensive overview of the types of stem cells and biomaterials used in the treatment of POI, including their biological characteristics and mechanisms of action. It explores various sources of stem cells, including embryonic stem cells, induced pluripotent stem cells, and adult stem cells, and their potential applications in regenerating ovarian tissue. Additionally, this paper discusses the development of biomaterials and scaffolds that mimic the natural ovarian microenvironment and support the growth and maturation of ovarian cells and follicles. Furthermore, the review highlights the challenges and ethical considerations associated with tissue engineering and stem cell-based therapies for POI and proposes potential solutions to address these issues. Overall, this paper aims to provide a comprehensive overview of the current state of research in tissue engineering and stem cell-based therapeutic strategies for POI and offers insights into future directions for improving treatment outcomes in this debilitating condition.

Current Status and Future Prospects of Stem Cell Therapy for Infertile Patients with Premature Ovarian Insufficiency

Premature ovarian insufficiency (POI), also known as premature menopause or premature ovarian failure, signifies the partial or complete loss of ovarian endocrine function and fertility before 40 years of age. This condition affects approximately 1% of women of childbearing age. Although 5-10% of patients may conceive naturally, conventional infertility treatments, including assisted reproductive technology, often prove ineffective for the majority. For infertile patients with POI, oocyte donation or adoption exist, although a prevalent desire persists among them to have biological children. Stem cells, which are characterized by their undifferentiated nature, self-renewal capability, and potential to differentiate into various cell types, have emerged as promising avenues for treating POI. Stem cell therapy can potentially reverse the diminished ovarian endocrine function and restore fertility. Beyond direct POI therapy, stem cells show promise in supplementary applications such as ovarian tissue cryopreservation and tissue engineering. However, technological and ethical challenges hinder the widespread clinical application of stem cells. This review examines the current landscape of stem cell therapy for POI, underscoring the importance of comprehensive assessments that acknowledge the diversity of cell types and functions. Additionally, this review scrutinizes the limitations and prospects associated with the clinical implementation of stem cell treatments for POI.

Stem Cells and Infertility: A Review of Clinical Applications and Legal Frameworks

Infertility is a condition defined by the failure to establish a clinical pregnancy after 12 months of regular, unprotected sexual intercourse or due to an impairment of a person's capacity to reproduce either as an individual or with their partner. The authors have set out to succinctly investigate, explore, and assess infertility treatments, harnessing the potential of stem cells to effectively and safely treat infertility; in addition, this paper will present the legal and regulatory complexities at the heart of stem cell research, with an overview of the legislative state of affairs in six major European countries. For couples who cannot benefit from assisted reproductive technologies (ART) to treat their infertility, stem-cells-based approaches have been shown to be a highly promising approach. Nonetheless, lingering ethical and immunological uncertainties require more conclusive findings and data before such treatment avenues can become mainstream and be applied on a large scale. The isolation of human embryonic stem cells (ESCs) is ethically controversial, since their collection involves the destruction of human embryonic tissue. Overall, stem cell research has resulted in important new breakthroughs in the treatment of infertility. The effort to untangle the complex web of ethical and legal issues associated with such therapeutic approaches will have to rely on evidence-based, broadly shared standards, guidelines, and best practices to make sure that the procreative rights of patients can be effectively reconciled with the core values at the heart of medical ethics.

Protective role of stem cells in POI: Current status and mechanism of action, a review article

Premature ovarian insufficiency (POI) has far-reaching consequences on women's life quality. Due to the lack of full recognition of the etiology and complexity of this disease, there is no appropriate treatment for infected patients. Recently, stem cell therapy has attracted the attention of regenerative medicine scholars and offered promising outcomes for POI patients. Several kinds of stem cells, such as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs) have been used for the treatment of ovarian diseases. However, their potential protective mechanisms are still unknown. Undoubtedly, a better understanding of the therapeutic molecular and cellular mechanisms of stem cells will address uncover strategies to increase their clinical application for multiple disorders such as POI. This paper describes a detailed account of the potential properties of different types of stem cells and provides a comprehensive review of their protective mechanisms, particularly MSC, in POI disorder. In addition, ongoing challenges and several strategies to improve the efficacy of MSC in clinical use are addressed. Therefore, this review will provide proof-of-concept for further clinical application of stem cells in POI.

Therapeutic Potential of Mesenchymal Stem Cells in PCOS

Polycystic ovary syndrome (PCOS) is a major reproductive endocrine disorder affecting different facets of a woman's life, comprising reproduction, metabolism, and mental health. Recently, several research groups have brought attention to the therapeutic capacity of mesenchymal stem cells (MSCs) for the treatment of female reproductive disorders. It is highlighted that the treatment with bone marrow mesenchymal stem cells (BMMSCs) considerably diminishes the levels of some inflammatory markers as well as essential genes for ovarian production of androgens, which are considerably higher in theca cells of PCOS women than in those of healthy cases. In addition, studies show that BMMSCs improve in vitro maturation (IVM) of germinal vesicles (GVs) and the number of antral follicles while lessening the number of primary and preantral follicles in mice with PCOS compared to healthy controls. Regarding adipose- derived mesenchymal stem cells (AdMSCs), these cells restore the ovarian structure, enhance the number of oocytes and corpora luteum, and diminish the number of aberrant cystic follicles in PCOS rats. Some research also indicates that umbilical cord mesenchymal stem cells (UC-MSCs) alleviate the inflammation of granulosa cells in women with PCOS. Therefore, due to the limited research on MSC therapy in PCOS, in this review, we summarize the current knowledge on the therapeutic potential of three types of MSCs: BMMSCs, AdMSCs, UC-MSCs and their secretome in the treatment of PCOS.

Articles in the field of infertility (2013-2022): a bibliometric analysis

To carry out an in-depth analysis of the scientific research on infertility, we performed the first bibliometric analysis focusing on studies involving global literature on infertility during the period 2013-2022. Analysis of 33239 articles in the field of infertility showed a significant increasing trend in the number of publications over the period 2013-2022, with authors mainly from the USA and China. Shanghai Jiao Tong University published the most articles. This study is the first to analyze the global field of infertility (2013-2022) from multiple indicators by bibliometrics, thus providing new insights into the research hotspots and development trends in the field of infertility.

A Review on Treatment of Premature Ovarian Insufficiency: Characteristics, Limitations, and Challenges of Stem Cell versus ExosomeTherapy

Premature ovarian insufficiency (POI) is a complex disorder that can result in varying degrees of infertility. Recently, mesenchymal stem cell (MSC) therapy and its derivatives, such as exosomes, have been introduced as novel strategies for the treatment of POI. This review discusses the features, limitations, and challenges of MSC and exosome therapy in the treatment of POI and provides readers with new insights for comparing and selecting chemical agents, optimizing doses, and other factors involved in study design and treatment strategies. MSC therapy has been shown to improve ovarian function in some animals with POI, but it can also have side effects such as high cost, time-consuming processes, limited lifespan and cell sources, loss of original characteristics during in vitro proliferation, dependence on specific culture environments, potential immune reactions, unknown therapeutic mechanisms, etc. However, exosome therapy is a newer therapy that has not been studied as extensively as MSC therapy, but that it has shown some promise in animal studies. The evidence for the effectiveness of MSC and exosome therapy is still limited, and more research is needed to determine whether these therapies are effective and safe for women with POI. This study presents a new perspective for researchers to advance their research in the fields of cell-based and cell-free therapies.

Menstrual blood-derived endometrial stem cell, a unique and promising alternative in the stem cell-based therapy for chemotherapy-induced premature ovarian insufficiency

Chemotherapy can cause ovarian dysfunction and infertility since the ovary is extremely sensitive to chemotherapeutic drugs. Apart from the indispensable role of the ovary in the overall hormonal milieu, ovarian dysfunction also affects many other organ systems and functions including sexuality, bones, the cardiovascular system, and neurocognitive function. Although conventional hormone replacement therapy can partly relieve the adverse symptoms of premature ovarian insufficiency (POI), the treatment cannot fundamentally prevent deterioration of POI. Therefore, effective treatments to improve chemotherapy-induced POI are urgently needed, especially for patients desiring fertility preservation. Recently, mesenchymal stem cell (MSC)-based therapies have resulted in promising improvements in chemotherapy-induced ovary dysfunction by enhancing the anti-apoptotic capacity of ovarian cells, preventing ovarian follicular atresia, promoting angiogenesis and improving injured ovarian structure and the pregnancy rate. These improvements are mainly attributed to MSC-derived biological factors, functional RNAs, and even mitochondria, which are directly secreted or indirectly translocated with extracellular vesicles (microvesicles and exosomes) to repair ovarian dysfunction. Additionally, as a novel source of MSCs, menstrual blood-derived endometrial stem cells (MenSCs) have exhibited promising therapeutic effects in various diseases due to their comprehensive advantages, such as periodic and non-invasive sample collection, abundant sources, regular donation and autologous transplantation. Therefore, this review summarizes the efficacy of MSCs transplantation in improving chemotherapy-induced POI and analyzes the underlying mechanism, and further discusses the benefit and existing challenges in promoting the clinical application of MenSCs in chemotherapy-induced POI.

Use of mesenchymal stem cells to enhance or restore fertility potential: a systematic review of available experimental strategies

STUDY QUESTION

To what extent does regenerative medicine with stem cell therapy help to address infertility issues for future clinical application?

SUMMARY ANSWER

Regenerative medicine using different stem cell sources is yielding promising results in terms of protecting the ovarian reserve from damage and senescence, and improving fertility potential in various preclinical settings.

WHAT IS KNOWN ALREADY

Regenerative medicine using stem cell therapy is emerging as a potential strategy to address a number of issues in the field of human reproduction. Indeed, different types of adult and fetal mesenchymal stem cells (MSCs) have been tested with promising results, owing to their ability to differentiate into different tissue lineages, move toward specific injured sites (homing), and generate a secretome with wound-healing, proangiogenic, and antioxidant capacities.

STUDY DESIGN SIZE DURATION

Guided by the checklist for preferred reporting items for systematic reviews and meta-analyses, we retrieved relevant studies from PubMed, Medline, and Embase databases until June 2023 using the following keywords: 'mesenchymal stem cells' AND 'ovarian follicles' OR 'ovarian tissue culture' OR 'ovarian follicle culture' OR 'cumulus oocyte complex'. Only peer-reviewed published articles written in English were included.

PARTICIPANTS/MATERIALS SETTING METHODS

The primary outcome for the experimental strategies was evaluation of the ovarian reserve, with a focus on follicle survival, number, and growth. Secondary outcomes involved analyses of other parameters associated with the follicle pool, such as hormones and growth factors, ovarian tissue viability markers including oxidative stress levels, oocyte growth and maturation rates, and of course pregnancy outcomes.

MAIN RESULTS AND THE ROLE OF CHANCE

Preclinical studies exploring MSCs from different animal origins and tissue sources in specific conditions were selected (n = 112), including: in vitro culture of granulosa cells, ovarian tissue and isolated ovarian follicles; ovarian tissue transplantation; and systemic or intraovarian injection after gonadotoxic or age-related follicle pool decline. Protecting the ovarian reserve from aging and gonadotoxic damage has been widely tested in vitro and in vivo using murine models and is now yielding initial data in the first ever case series of patients with premature ovarian insufficiency. Use of MSCs as feeder cells in ovarian tissue culture was found to improve follicle outcomes and oocyte competence, bringing us one step closer to future clinical application. MSCs also have proved effective at boosting revascularization in the transplantation site when grafting ovarian tissue in experimental animal models.

LIMITATIONS REASONS FOR CAUTION

While preclinical results look promising in terms of protecting the ovarian reserve in different experimental models (especially those in vitro using various mammal experimental models and in vivo using murine models), there is still a lot of work to do before this approach can be considered safe and successfully implemented in a clinical setting.

WIDER IMPLICATIONS OF THE FINDINGS

All gathered data on the one hand show that regenerative medicine techniques are quickly gaining ground among innovative techniques being developed for future clinical application in the field of reproductive medicine. After proving MSC effectiveness in preclinical settings, there is still a lot of work to do before MSCs can be safely and effectively used in different clinical applications.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (FNRS-PDR T.0077.14, FNRS-CDR J.0063.20, and grant 5/4/150/5 awarded to Marie-Madeleine Dolmans), Fonds Spéciaux de Recherche, and the Fondation St Luc. None of the authors have any competing interest to disclose.

REGISTRATION NUMBER

N/A.

Biological therapies for premature ovarian insufficiency: what is the evidence?

Premature Ovarian Insufficiency (POI) is a multi-factorial disorder that affects women of reproductive age. The condition is characterized by the loss of ovarian function before the age of 40 years and several factors have been identified to be implicated in its pathogenesis. Remarkably though, at least 50% of women have remaining follicles in their ovaries after the development of ovarian insufficiency. Population data show that approximately up to 3.7% of women worldwide suffer from POI and subsequent infertility. Currently, the treatment of POI-related infertility involves oocyte donation. However, many women with POI desire to conceive with their own ova. Therefore, experimental biological therapies, such as Platelet-Rich Plasma (PRP), Exosomes (exos) therapy, In vitro Activation (IVA), Stem Cell therapy, MicroRNAs and Mitochondrial Targeting Therapies are experimental treatment strategies that focus on activating oogenesis and folliculogenesis, by upregulating natural biochemical pathways (neo-folliculogenesis) and improving ovarian microenvironment. This mini-review aims at identifying the main advantages of these approaches and exploring whether they can underpin existing assisted reproductive technologies.

Effect of preconditioning of human umbilical cord mesenchymal stem cells with hydrogen peroxide on the therapeutic potential of MSCs in the cyclophosphamide -induced premature ovarian failure mice model

OBJECTIVE

Exposure of stem cells to sublethal levels of hydrogen peroxide (H2O2) can prevent oxidative stress-induced apoptosis. In the present study, the effects of H2O2 preconditioning on the therapeutic potential of human umbilical vein cord mesenchymal stem cells (hUCV-MSCs) were evaluated in a murine model of premature ovarian failure.

MATERIALS AND METHODS

Mature mice were divided into 4 groups, and 10 mice were incorporated into each group. The control (Ctrl) group received phosphate buffered saline (PBS) intraperitoneal (IP), and the CTX group was injected IP with cyclophosphamide (CTX). The CTX + MSC group after receiving CTX was injected with a single dose of hUCV-MSCs labeled with CM-DiI intravenously (IV), whereas the CTX + preMSCs group after CTX injection received preconditioned MSCs with H2O2 IV. Seven days later, the mice were euthanized, and their ovaries were removed for histological studies such as H&E staining and the TUNEL assay. Furthermore, the numbers of CM-DiI-labeled hUCV-MSCs in the different regions of the ovary were calculated. FSH and estradiol values in the serum were measured.

RESULTS

Our studies showed that CTX caused degenerative changes and follicular loss in the ovary. The number of follicles in the CTX + MSCs and CTX + PreMSCs groups was significantly higher compared to the CTX group. In addition, in the CTX + PreMSCs group, the numbers of different types of follicles were higher than in the CTX-MSC group. Immunohistochemical studies in the CTX + MSCs and CTX + PreMSCs groups showed little evidence of TUNEL positivity compared with the CTX group. Moreover, the apoptotic index decreased in the CTX + PreMSCs group compared to the CTX + MSCs group. Moreover, CM-DiI-labeled MSCs in the ovary in the CTX + pre-MSCs group were higher than in the CTX + MSCs group.

CONCLUSION

Our experiment offers preconditioning as an effective strategy in stem cell therapy to potentiate MSCs' therapeutic efficacy in ovarian function failure.

Unlocking the Potential of Mesenchymal Stem Cells in Gynecology: Where Are We Now?

Stem cells, with their remarkable capacity for differentiation into diverse cell types, are vital for the development as well as maintenance of health and homeostasis. Two unique abilities set them apart from other cells: self-renewal and the capacity for differentiation. They play important roles in embryogenesis, development, regeneration, and various other processes. Over the last decade, there has been increased interest in their potential use in the treatment of numerous diseases and disorders across multiple fields of medicine in acute, chronic, innate, and acquired diseases. Stem cells are key to maintaining the body's homeostasis and regulating growth and tissue functions. There are several types of stem cells-embryonic, adult, and human-induced pluripotent cells. Currently, mesenchymal stem cells are of great interest due to their regenerative, immunomodulatory, analgesic, and antimicrobial (anti-inflammatory) effects. Recent studies have shown the potent regenerative effect of stem cell therapy in gynecologic diseases such as infertility, Asherman syndrome, lichen sclerosus, polycystic ovary syndrome, premature ovarian insufficiency, genitourinary syndrome of menopause, and rectovaginal fistulas. Moreover, the successful isolation of oogonial stem cells could lead to a revolution in the field of gynecology and the potential treatment of the conditions discussed. This review aims to provide a better understanding of the latest therapeutic options involving stem cells and raise awareness of this promising yet not widely known topic in gynecology and medicine in general.

Adipose-derived stem cells promote the repair of chemotherapy-induced premature ovarian failure by inhibiting granulosa cells apoptosis and senescence

BACKGROUND

Chemotherapeutic drugs, particularly alkylating cytotoxics such as cyclophosphamide (CTX), play an important role to induce premature ovarian failure (POF). Hormone replacement therapy (HRT) is a widely used treatment to improve hormone secretion. However, the long-term HRT increases the risk of breast cancer and cardiovascular disease are attracting concerns. Therefore, there is an urgent need to develop a safe and effective treatment for POF.

METHOD

Adipose-derived stem cells (ADSCs) were isolated and identified from human adipose tissue. For POF modeling, CTX were intraperitoneal injected into CTX-acute group, CTX-chronic group, CTX-acute + ADSCs group and CTX-chronic + ADSCs group rats; For transplantation, ADSCs were transplanted into POF rats through tail-vein. The control group rats were injected with PBS. The effects of POF modeling and transplantation were determined by estrous cycle analysis, histopathological analysis, immunohistochemical staining and apoptosis-related marker. To evaluate the effects of ADSC on granulosa cells in vitro, CTX-induced senescent KGN cells were co-cultured with ADSCs, and senescent-related marker expression was investigated by immunofluorescent staining.

RESULTS

In vivo studies revealed that ADSCs transplantation reduced the apoptosis of ovarian granulosa cells and secretion of follicle-stimulating hormone. The number of total follicles, primordial follicles, primary follicles, and mature follicles and secretion of anti-Müllerian hormone and estradiol (E2) were also increased by ADSCs. The estrous cycle was also improved by ADSC transplantation. Histopathological analysis showed that CTX-damaged ovarian microenvironment was improved by ADSCs. Furthermore, TUNEL staining indicated that apoptosis of granulosa cells was decreased by ADSCs. In vitro assay also demonstrated that ADSC markedly attenuated CTX-induced senescence and apoptosis of granulosa cell. Mechanistically, both in vivo and in vitro experiments proved that ADSC transplantation suppressed activation of the PI3K/Akt/mTOR axis.

CONCLUSION

Our experiment demonstrated that a single injection of high-dose CTX was a less damaging chemotherapeutic strategy than continuous injection of low-dose CTX, and tail-vein injection of ADSCs was a potential approach to promote the restoration of CTX-induced POF.

Ovarian rescue in women with premature ovarian insufficiency: facts and fiction

The ovary has a comparatively short functional lifespan compared with other organs, and genetic and pathological injuries can further shorten its functional life. Thus, preserving ovarian function should be considered in the context of women with threats to ovarian reserve, such as ageing, premature ovarian insufficiency (POI) and diminished ovarian reserve (DOR). Indeed, one-third of women with POI retain resting follicles that can be reactivated to produce competent oocytes, as proved by the in-vitro activation of dormant follicles. This paper discusses mechanisms and clinical data relating to new therapeutic strategies using ovarian fragmentation, stem cells or platelet-rich plasma to regain ovarian function in women of older age (>38 years) or with POI or DOR. Follicle reactivation techniques show promising experimental outcomes and have been successful in some cases, when POI is established or DOR diagnosed; however, there is scarce clinical evidence to warrant their widespread clinical use. Beyond these contexts, also discussed is how new insights into the biological mechanisms governing follicular dynamics and oocyte competence may play a role in reversing ovarian damage, as no technique modifies oocyte quality. Additional studies should focus on increasing follicle number and quality. Finally, there is a small but important subgroup of women lacking residual follicles and requiring oocyte generation from stem cells.

Human Pluripotent Stem Cell-Mesenchymal Stem Cell-Derived Exosomes Promote Ovarian Granulosa Cell Proliferation and Attenuate Cell Apoptosis Induced by Cyclophosphamide in a POI-like Mouse Model

Premature ovarian insufficiency (POI) is a complex disease which causes amenorrhea, hypergonadotropism and infertility in patients no more than 40 years old. Recently, several studies have reported that exosomes have the potential to protect ovarian function using a POI-like mouse model induced by chemotherapy drugs. In this study, the therapeutic potential of exosomes derived from human pluripotent stem cell-mesenchymal stem cells (hiMSC exosomes) was evaluated through a cyclophosphamide (CTX)-induced POI-like mouse model. POI-like pathological changes in mice were determined by serum sex-hormones levels and the available number of ovarian follicles. The expression levels of cellular proliferation proteins and apoptosis-related proteins in mouse ovarian granulosa cells were measured using immunofluorescence, immunohistochemistry and Western blotting. Notably, a positive effect on the preservation of ovarian function was evidenced, since the loss of follicles in the POI-like mouse ovaries was slowed. Additionally, hiMSC exosomes not only restored the levels of serum sex hormones, but also significantly promoted the proliferation of granulosa cells and inhibited cell apoptosis. The current study suggests that the administration of hiMSC exosomes in the ovaries can preserve female-mouse fertility.

Reduced graphene oxide-embedded nerve conduits loaded with bone marrow mesenchymal stem cell-derived extracellular vesicles promote peripheral nerve regeneration

We previously combined reduced graphene oxide (rGO) with gelatin-methacryloyl (GelMA) and polycaprolactone (PCL) to create an rGO-GelMA-PCL nerve conduit and found that the conductivity and biocompatibility were improved. However, the rGO-GelMA-PCL nerve conduits differed greatly from autologous nerve transplants in their ability to promote the regeneration of injured peripheral nerves and axonal sprouting. Extracellular vesicles derived from bone marrow mesenchymal stem cells (BMSCs) can be loaded into rGO-GelMA-PCL nerve conduits for repair of rat sciatic nerve injury because they can promote angiogenesis at the injured site. In this study, 12 weeks after surgery, sciatic nerve function was measured by electrophysiology and sciatic nerve function index, and myelin sheath and axon regeneration were observed by electron microscopy, immunohistochemistry, and immunofluorescence. The regeneration of microvessel was observed by immunofluorescence. Our results showed that rGO-GelMA-PCL nerve conduits loaded with BMSC-derived extracellular vesicles were superior to rGO-GelMA-PCL conduits alone in their ability to increase the number of newly formed vessels and axonal sprouts at the injury site as well as the recovery of neurological function. These findings indicate that rGO-GelMA-PCL nerve conduits loaded with BMSC-derived extracellular vesicles can promote peripheral nerve regeneration and neurological function recovery, and provide a new direction for the curation of peripheral nerve defect in the clinic.

Research Progress on the Etiology and Treatment of Premature Ovarian Insufficiency

Background

Menopause in women marks the knot of reproductive life, and menopause is defined as the last menstrual period in a woman, but this is caused by the failure of the ovarian reserve. The average age of natural menopause in the general population of women has remained around 50-52 years. Premature ovarian insufficiency (POI) is a debilitating clinical syndrome that manifests as a decline in ovarian function in women under 40. This condition is a prominent cause of female infertility.

Summary

POI is a debilitating condition that not only wreaks havoc on patients' physical and mental well-being but also imposes substantial mental, psychological, and economic burdens, particularly on women. In addition to diminished fertility, individuals afflicted with POI face an elevated risk of developing debilitating conditions such as osteoporosis and cardiovascular disease. The etiologies of POI are highly heterogeneous, and it can be caused by spontaneous genetic defects or induced by autoimmune diseases, infections, and iatrogenic or environmental factors. Alarmingly, idiopathic POI, a subtype characterized by an unknown etiology, accounts for more than half of all POI cases. Currently, clinical interventions for POI primarily consist of hormone replacement therapy. Fertility preservation methods are cryopreservation of embryos, oocytes, and ovarian tissue. Immunological interventions, gene editing techniques, and stem cell-based therapies are being explored to unravel the diverse etiologies and underlying mechanisms of POI, thereby enabling the identification of optimal therapeutic interventions. These innovative approaches offer unprecedented opportunities to advance the field of reproductive medicine.

Key Messages

The main aim of this paper was to offer a succinct summary of the latest research breakthroughs concerning the elucidation of the mechanisms governing the origin and management of POI.

Identification of Common and Specific Genes Involved in Mouse Models of Age-Related and Cyclophosphamide-Induced Diminished Ovarian Reserve

Diminished ovarian reserve (DOR) is an etiologically heterogeneous disorder that usually leads to poor reproductive outcomes. Does a specific or common pathogenesis exist for DOR subtypes with different etiologies? Two frequently used mouse models, age-related DOR (AR-DOR) and cyclophosphamide (CTX)-induced DOR (CTX-DOR), were successfully established, and RNA sequencing was performed on ovarian tissue samples. Differentially expressed genes (DEGs) in each subtype and common DEGs (co-DEGs) in the two subtypes were identified. Subsequently, we performed comprehensive bioinformatics analyses, including an evaluation of immune cell infiltration. Finally, the genes of interest were further validated by performing RT-qPCR and immunohistochemistry. In AR-DOR mice, functional enrichment analyses showed that upregulated DEGs were mainly involved in the inflammatory/immune response, while downregulated DEGs were involved in DNA damage repair. In CTX-DOR mice, the inflammatory/immune response and cell apoptosis played significant roles. Meanwhile, 406 co-DEGs were identified from the two models. The biological functions of these co-DEGs were associated with inflammatory/immune responses. The analysis of immune cell infiltration showed reduced infiltration of Treg cells, as well as increased infiltration of M0 macrophages, NK resting, and T cells CD4 follicular in both DOR subtypes. The results of the validation experiments were consistent with the RNA sequencing data. In conclusion, the inflammatory/immune response might be the common pathogenesis for the two DOR subtypes, while DNA repair and cell apoptosis may have different roles in the two subtypes. These results may provide potential insights for mechanistic research and therapeutic targets of DOR.

Cell therapy for the treatment of reproductive diseases and infertility: an overview from the mechanism to the clinic alongside diagnostic methods

Infertility is experienced by 8%-12% of adults in their reproductive period globally and has become a prevalent concern. Besides routine therapeutic methods, stem cells are rapidly being examined as viable alternative therapies in regenerative medicine and translational investigation. Remarkable progress has been made in understanding the biology and purpose of stem cells. The affected pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSCs) are further studied for their possible use in reproductive medicine, particularly for infertility induced by premature ovarian insufficiency and azoospermia. Accordingly, this study discusses current developments in the use of some kinds of MSCs such as adipose-derived stem cells, bone marrow stromal cells, umbilical cord MSCs, and menstrual blood MSCs. These methods have been used to manage ovarian and uterine disorders, and each technique presents a novel method for the therapy of infertility.

Stem Cell-Based Therapeutic Strategies for Premature Ovarian Insufficiency and Infertility: A Focus on Aging

Reproductive aging is on the rise globally and inseparable from the entire aging process. An extreme form of reproductive aging is premature ovarian insufficiency (POI), which to date has mostly been of idiopathic etiology, thus hampering further clinical applications and associated with enormous socioeconomic and personal costs. In the field of reproduction, the important functional role of inflammation-induced ovarian deterioration and therapeutic strategies to prevent ovarian aging and increase its function are current research hotspots. This review discusses the general pathophysiology and relative causes of POI and comprehensively describes the association between the aging features of POI and infertility. Next, various preclinical studies of stem cell therapies with potential for POI treatment and their molecular mechanisms are described, with particular emphasis on the use of human induced pluripotent stem cell (hiPSC) technology in the current scenario. Finally, the progress made in the development of hiPSC technology as a POI research tool for engineering more mature and functional organoids suitable as an alternative therapy to restore infertility provides new insights into therapeutic vulnerability, and perspectives on this exciting research on stem cells and the derived exosomes towards more effective POI diagnosis and treatment are also discussed.

“Adipose-derived mesenchymal stem cell therapy for the management of female sexual dysfunction: Literature reviews and study design of a clinical trial”

Hormone imbalance and female sexual dysfunction immensely affect perimenopausal female health and quality of life. Hormone therapy can improve female hormone deficiency, but long-term use increases the risk of cardiovascular diseases and cancer. Therefore, it is necessary to develop a novel effective treatment to achieve long-term improvement in female general and sexual health. This study reviewed factors affecting syndromes of female sexual dysfunction and its current therapy options. Next, the authors introduced research data on mesenchymal stromal cell/mesenchymal stem cell (MSC) therapy to treat female reproductive diseases, including Asherman’s syndrome, premature ovarian failure/primary ovarian insufficiency, and vaginal atrophy. Among adult tissue-derived MSCs, adipose tissue-derived stem cells (ASCs) have emerged as the most potent therapeutic cell therapy due to their abundant presence in the stromal vascular fraction of fat, high proliferation capacity, superior immunomodulation, and strong secretion profile of regenerative factors. Potential mechanisms and side effects of ASCs for the treatment of female sexual dysfunction will be discussed. Our phase I clinical trial has demonstrated the safety of autologous ASC therapy for women and men with sexual hormone deficiency. We designed the first randomized controlled crossover phase II trial to investigate the safety and efficacy of autologous ASCs to treat female sexual dysfunction in perimenopausal women. Here, we introduce the rationale, trial design, and methodology of this clinical study. Because aging and metabolic diseases negatively impact the bioactivity of adult-derived MSCs, this study will use ASCs cultured in physiological oxygen tension (5%) to cope with these challenges. A total of 130 perimenopausal women with sexual dysfunction will receive two intravenous infusions of autologous ASCs in a crossover design. The aims of the proposed study are to evaluate 1) the safety of cell infusion based on the frequency and severity of adverse events/serious adverse events during infusion and follow-up and 2) improvements in female sexual function assessed by the Female Sexual Function Index (FSFI), the Utian Quality of Life Scale (UQOL), and the levels of follicle-stimulating hormone (FSH) and estradiol. In addition, cellular aging biomarkers, including plasminogen activator inhibitor-1 (PAI-1), p16 and p21 expression in T cells and the inflammatory cytokine profile, will also be characterized. Overall, this study will provide essential insights into the effects and potential mechanisms of ASC therapy for perimenopausal women with sexual dysfunction. It also suggests direction and design strategies for future research.

Stem Cells and Organs-on-chips: New Promising Technologies for Human Infertility Treatment

Having biological children remains an unattainable dream for most couples with reproductive failure or gonadal dysgenesis. The combination of stem cells with gene editing technology and organ-on-a-chip models provides a unique opportunity for infertile patients with impaired gametogenesis caused by congenital disorders in sex development or cancer survivors. But how will these technologies overcome human infertility? This review discusses the regenerative mechanisms, applications, and advantages of different types of stem cells for restoring gametogenesis in infertile patients, as well as major challenges that must be overcome before clinical application. The importance and limitations of in vitro generation of gametes from patient-specific human-induced pluripotent stem cells (hiPSCs) will be discussed in the context of human reproduction. The potential role of organ-on-a-chip models that can direct differentiation of hiPSC-derived primordial germ cell-like cells to gametes and other reproductive organoids is also explored. These rapidly evolving technologies provide prospects for improving fertility to individuals and couples who experience reproductive failure.

Adipose mesenchymal stem cell-derived exosomal microRNAs ameliorate polycystic ovary syndrome by protecting against metabolic disturbances

Polycystic ovary syndrome (PCOS) is the most common endocrine and metabolic disorder in women of childbearing age. Adipose mesenchymal stem cells (AMSCs) secrete cytokines involved in the regulation of metabolism and immunity. However, it remains unclear whether exosomes secreted by AMSCs (AMSC-EXOs) can rescue the polycystic phenotype and metabolic dysfunction in PCOS ovaries. Here, we show that AMSC-EXOs can protect against metabolic disturbances, ameliorate ovarian polycystic, and improve fertility in a rat model of PCOS. AMSC-EXOs inhibited the expression of B-cell translocation gene 2 by transferring miR-21-5p to the livers of rats with PCOS, thus activating the IRS1/AKT pathway and increasing hepatic metabolism. The role of AMSC-EXOs in transferring miRNAs to the liver to improve metabolic dysfunction in PCOS and reproduction by rescuing a non-coding RNA pathway was also discovered. This study provides a theoretical basis for the use of rat adipose stem cells and their secreted exosomes to treat PCOS.

Biological mechanisms and applied prospects of mesenchymal stem cells in premature ovarian failure

Premature ovarian failure (POF), also known as primary ovarian insufficiency (POI), refers to the loss of ovarian function in women after puberty and before the age of 40 characterized by high serum gonadotropins and low estrogen, irregular menstruation, amenorrhea, and decreased fertility. However, the specific pathogenesis of POF is unexplained, and there is no effective therapy for its damaged ovarian tissue structure and reduced reserve function. Mesenchymal stem cells (MSCs), with multidirectional differentiation potential and self-renewal ability, as well as the cytokines and exosomes they secrete, have been studied and tested to play an active therapeutic role in a variety of degenerative pathologies, and MSCs are the most widely used stem cells in regenerative medicine. MSCs can reverse POI and enhance ovarian reserve function through differentiation into granulosa cells (GCs), immune regulation, secretion of cytokines and other nutritional factors, reduction of GCs apoptosis, and promotion of GCs regeneration. Many studies have proved that MSCs may have a restorative effect on the structure and fertility of injured ovarian tissues and turn to be a useful clinical approach to the treatment of patients with POF in recent years. We intend to use MSCs-based therapy to completely reverse POI in the future.

Melatonin enhances autologous adipose-derived stem cells to improve mouse ovarian function in relation to the SIRT6/NF-κB pathway

Background

Premature ovarian insufficiency (POI) is the main cause of female infertility. Adipose-derived stem cells (ADSCs) are ideal candidates for the treatment of POI. However, some deficient biological characteristics of ADSCs limit their utility. This study investigated whether melatonin (MLT)-pretreated autologous ADSCs were superior to ADSCs alone in the treatment of the POI mouse model.

Methods

Autologous ADSCs were isolated and cultured in MLT-containing medium. Surface markers of ADSCs were detected by flow cytometry. To determine the effect of MLT on ADSCs, CCK-8 assay was used to detect ADSCs proliferation and enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of cytokines. The POI model was established by intraperitoneal injection of cyclophosphamide and busulfan. Then, MLT-pretreated autologous ADSCs were transplanted into mice by intraovarian injection. After 7 days of treatment, ovarian morphology, follicle counts, and sex hormones levels were evaluated by hematoxylin and eosin (H&E) staining and ELISA, and the recovery of fertility was also observed. The expressions of SIRT6 and NF-κB were detected by immunohistochemical (IHC) staining and quantitative real-time polymerase chain reaction (qRT-PCR).

Results

Flow cytometry showed that autologous ADSCs expressed CD90 (99.7%) and CD29 (97.5%). MLT can not only promote the proliferation of ADSCs but also boost their secretory function, especially when ADSCs were pretreated with 5 µM MLT for 3 days, improving the interference effect. After transplantation of autologous ADSCs pretreated with 5 µM MLT, the serum hormone levels and reproductive function were significantly recovered, and the mean counts of primordial follicle increased. At the same time, the expression of SIRT6 was remarkably increased and the expression of NF-κB was significantly decreased in this group.

Conclusions

MLT enhances several effects of ADSCs in restoring hormone levels, mean primordial follicle counts, and reproductive capacity in POI mice. Meanwhile, our results suggest that the SIRT6/NF-κB signal pathway may be the potential therapeutic mechanism for ADSCs to treat POI.

Drug-free in vitro activation combined with 3D-bioprinted adipose-derived stem cells restores ovarian function of rats with premature ovarian insufficiency

BACKGROUND

Emerging drug-free in vitro activation (IVA) technique enables patients with premature ovarian insufficiency (POI) to restore ovarian function and conceive their own genetic offspring. However, various issues have greatly restricted its clinical application. Transplantation of adipose-derived stem cells (ADSCs) has promising roles in restoring ovarian function of rats with POI, but insufficient retention has greatly hampered their efficiency. Here, we designed a 3D-bioprinted engineering ovary composed of drug-free IVA and ADSCs, which may prolong the retention of ADSCs and construct an early vascular microenvironment, thus compensating for the disadvantages of drug-free IVA to some extent and ameliorating impaired ovarian function in the POI rats.

METHODS

After intraperitoneal injection of cyclophosphamide, the POI model rats were randomized into 5 groups: (1) POI group; (2) ovarian fragments group; (3) 3D scaffold combined with ovarian fragments group; (4) ovarian fragments combined with ADSCs group; (5) 3D scaffold with ADSCs combined with ovarian fragments as 3D-bioprinted engineering ovary group. Normal rats were identified as the control group. The localization of CM-Dil-labeled ADSCs and co-localization with CD31 were observed to examine the distribution and underlying mechanism of differentiation. Histomorphological and immunohistochemical analyses were performed to calculate follicle number and assess proliferation and apoptosis of granulosa cells (GCs). Immunofluorescence staining was used to evaluate angiogenesis. Hormone levels were measured to evaluate the restoration of endocrine axis. Western blot analysis and RT-PCR were conducted to explore the potential mechanism.

RESULTS

CM-Dil-labeled ADSCs were distributed in the interstitium of ovaries and had significantly higher retention in the 3D-bioprinted engineering ovary group. Several regions of the co-staining for CM-Dil and CD31 were in the area of vascular endothelial cells. Meanwhile, the follicle counts, GCs proliferation, neoangiogenesis, and hormone levels were significantly improved in the 3D-bioprinted engineering ovary group, as compared with other groups. Furthermore, the ovarian function was ameliorated and angiogenesis was promoted through regulating the PI3K/AKT pathway.

CONCLUSION

Our results suggested that 3D-bioprinted engineering ovary had great potential for restoring impaired ovarian function of rats with POI, which could compensate for the disadvantages of drug-free IVA to some extent.

Enhancing Stem Cell-Based Therapeutic Potential by Combining Various Bioengineering Technologies

Stem cell-based therapeutics have gained tremendous attention in recent years due to their wide range of applications in various degenerative diseases, injuries, and other health-related conditions. Therapeutically effective bone marrow stem cells, cord blood- or adipose tissue-derived mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), and more recently, induced pluripotent stem cells (iPSCs) have been widely reported in many preclinical and clinical studies with some promising results. However, these stem cell-only transplantation strategies are hindered by the harsh microenvironment, limited cell viability, and poor retention of transplanted cells at the sites of injury. In fact, a number of studies have reported that less than 5% of the transplanted cells are retained at the site of injury on the first day after transplantation, suggesting extremely low (<1%) viability of transplanted cells. In this context, 3D porous or fibrous national polymers (collagen, fibrin, hyaluronic acid, and chitosan)-based scaffold with appropriate mechanical features and biocompatibility can be used to overcome various limitations of stem cell-only transplantation by supporting their adhesion, survival, proliferation, and differentiation as well as providing elegant 3-dimensional (3D) tissue microenvironment. Therefore, stem cell-based tissue engineering using natural or synthetic biomimetics provides novel clinical and therapeutic opportunities for a number of degenerative diseases or tissue injury. Here, we summarized recent studies involving various types of stem cell-based tissue-engineering strategies for different degenerative diseases. We also reviewed recent studies for preclinical and clinical use of stem cell-based scaffolds and various optimization strategies.

Comparison of CD146 +/- mesenchymal stem cells in improving premature ovarian failure

BACKGROUND

Mesenchymal stem cells (MSCs) are a heterogeneous group of subpopulations with differentially expressed surface markers. CD146 + MSCs correlate with high therapeutic and secretory potency. However, their therapeutic efficacy and mechanisms in premature ovarian failure (POF) have not been explored.

METHODS

The umbilical cord (UC)-derived CD146 +/- MSCs were sorted using magnetic beads. The proliferation of MSCs was assayed by dye670 staining and flow cytometry. A mouse POF model was established by injection of cyclophosphamide and busulfan, followed by treatment with CD146 +/- MSCs. The therapeutic effect of CD146 +/- MSCs was evaluated based on body weight, hormone levels, follicle count and reproductive ability. Differential gene expression was identified by mRNA sequencing and validated by RT-PCR. The lymphocyte percentage was detected by flow cytometry.

RESULTS

CD146 +/- MSCs had similar morphology and surface marker expression. However, CD146 + MSCs exhibited a significantly stronger proliferation ability. Gene profiles revealed that CD146 + MSCs had a lower levels of immunoregulatory factor expression. CD146 + MSCs exhibited a stronger ability to inhibit T cell proliferation. CD146 +/- MSCs treatment markedly restored FSH and E2 hormone secretion level, reduced follicular atresia, and increased sinus follicle numbers in a mouse POF model. The recovery function of CD146 + MSCs in a reproductive assay was slightly improved than that of CD146 - MSCs. Ovary mRNA sequencing data indicated that UC-MSCs therapy improved ovarian endocrine locally, which was through PPAR and cholesterol metabolism pathways. The percentages of CD3, CD4, and CD8 lymphocytes were significantly reduced in the POF group compared to the control group. CD146 + MSCs treatment significantly reversed the changes in lymphocyte percentages. Meanwhile, CD146 - MSCs could not improve the decrease in CD4/8 ratio induced by chemotherapy.

CONCLUSION

UC-MSCs therapy improved premature ovarian failure significantly. CD146 +/- MSCs both had similar therapeutic effects in repairing reproductive ability. CD146 + MSCs had advantages in modulating immunology and cell proliferation characteristics.

Sesamol protects the function and structure of rat ovaries against side effects of cyclophosphamide by decreasing oxidative stress and apoptosis

AIM

Chemotherapy with cyclophosphamide can damage ovaries and cause infertility in girls and women. Sesamol is a phenolic antioxidant that can protect various organs from damage. The purpose of this study was to evaluate the effects of sesamol on protecting the function and structure of rat ovaries against the side effects of a chemotherapy model with cyclophosphamide.

METHODS

Twenty-four adult female Wistar rats were randomly divided into three groups: (1) normal group, without any treatment, (2) control group, immediately after receiving cyclophosphamide, 0.5% dimethyl sulfoxide (DMSO) as the solvent of sesamol was intraperitoneally injected for 14 consecutive days, (3) sesamol group, immediately after receiving cyclophosphamide, 50 mg/kg sesamol was intraperitoneally injected for 14 consecutive days. Four weeks after the last injection, superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels in the ovary, anti-Mullerian hormone (AMH) levels in the serum, number of ovarian follicles in different stages, and expression of proteins growth differentiation factor-9 (GDF-9), Bcl-2, and Bax in the ovary were evaluated.

RESULTS

The results of SOD activity and MDA levels in the ovary, AMH levels in the serum, number of ovarian follicles in different stages, and expression of proteins GDF9, Bcl-2, and Bax in the ovary were significantly more favorable in the sesamol group than the control group.

CONCLUSIONS

The results suggest that sesamol may protect function and structure in the rat ovaries against side effects of the chemotherapy model with cyclophosphamide by decreasing oxidative stress and apoptosis in the ovary.

A bibliometric analysis of primary ovarian insufficiency from 2010 to 2020

OBJECTIVE

This study aimed to carry out a bibliometric analysis of primary ovarian insufficiency (POI) from 2010 to 2020 and to reveal the research status and hotspots in the future.

METHOD

A total of 3087 articles and reviews related to POI published from 2010 to 2020 retrieved from the Web of Science Core Collection were used for bibliometric analysis. CiteSpace and VOSviewer were adopted to analyze countries and regions, organizations, authors, journals, keywords and co-cited references.

RESULTS

The number of publications about POI increased year by year. The USA produced the largest number of publications and the most influence in this field. The main research directions of POI can be roughly divided into four aspects according to the analysis of keywords and co-cited references: genetic research of POI; stem cell therapy for patients with POI; prediction of ovarian function; and fertility preservation of cancer patients. Genetic research and stem cell therapy may become research hotspots in the future.

CONCLUSION

This study might be the first bibliometric study to analyze publications of POI from multiple indicators, in order to provide new opinions for the research trends and possible hotspots of POI.

Protective Effects of Platelet-rich plasma for in vitro Fertilization of Rats with Ovarian Failure Induced by Cyclophosphamide

OBJECTIVE

 Premature ovarian insufficiency (POI) contributes significantly to female infertility. Cyclophosphamide (CYC has adverse effects on folliculogenesis. Platelet-rich plasma (PRP) is an autologous product rich in many growth factors. We evaluated the protective effect of PRP on in vitro fertilization in female rats with CYC-induced ovarian damage.

METHODS

 Twenty-eight adult female Sprague-Dawley rats were randomly divided into four groups. Group 1 (control-sodium chloride 0.9%; 1 mL/kg, single-dose intraperitoneal [IP] injection); group 2 (CYC), 75 mg/kg, single-dose IP injection and sodium chloride 0.9% (1 mL/kg, single-dose IP injection); group 3 CYC plus PRP, CYC (75 mg/kg, single-dose and PRP (200 μl, single-dose) IP injection); and group 4 (PRP, 200 μl, single-dose IP injection).

RESULTS

 In the comparisons in terms of M1 and M2 oocytes, it was observed that the CYC group presented a significantly lower amount than the control, CYC/PRP, and PRP groups. (for M1, p = 0.000, p = 0.029, p = 0.025; for M2, p = 0.009, p = 0.004, p = 0.000, respectively). The number of fertilized oocytes and two-celled good quality embryos was found to be statistically significant between the CYC and control groups, CYC + PRP and PRP groups (p = 0.009, p = 0.001, p = 0.000 for oocytes, respectively. For embryos; p = 0.016, p = 0.002, p = 0.000).

CONCLUSION

 Platelet-rich plasma can protect the ovarian function against damage caused by CYC, and, in addition, it improves oocyte count and the development of embryos as a result of oocyte stimulation during the IVF procedure.

Mesenchymal stem cells combined with autocrosslinked hyaluronic acid improve mouse ovarian function by activating the PI3K-AKT pathway in a paracrine manner

Background

Declining ovarian function in advance-aged women and in premature ovarian insufficiency (POI) patients seriously affects quality of life, and there is currently no effective treatment to rescue ovarian function in clinic. Stem cell transplantation is a promising therapeutic strategy for ovarian aging, but its clinical application is limited due to the low efficiency and unclear mechanism. Here, a novel combination of umbilical cord-mesenchymal stem cells (UC-MSCs) and autocrosslinked hyaluronic acid (HA) gel is explored to rescue ovarian reserve and fecundity in POI and naturally aging mice.

Methods

To investigate HA prolonged the survival after UC-MSCs transplantation, PCR and immunofluorescence were performed to track the cells on day 1, 3, 7 and 14 after transplantation. The effects of HA on UC-MSCs were analyzed by CCK8 assay, RNA-sequencing and 440 cytokine array. In vivo experiments were conducted to evaluate the therapeutic effects of UC-MSCs combined with HA transplantation in 4-vinylcyclohexene diepoxide (VCD)-induced POI mice and naturally aging mice model. Ovarian function was analyzed by ovarian morphology, follicle counts, estrous cycle, hormone levels and fertility ability. To investigate the mechanisms of stem cell therapy, conditioned medium was collected from UC-MSCs and fibroblast. Both in vitro ovarian culture model and 440 cytokine array were applied to assess the paracrine effect and determine the underlying mechanism. Hepatocyte growth factor (HGF) was identified as an effective factor and verified by HGF cytokine/neutralization antibody supplementation into ovarian culture system.

Results

HA not only prolongs the retention of UC-MSCs in the ovary, but also boosts their secretory function, and UC-MSCs promote follicular survival by activating the PI3K-AKT pathway through a paracrine mechanism both in vitro and in vivo. More importantly, HGF is identified as the key functional cytokine secreted by MSCs.

Conclusions

The results show that HA is an excellent cell scaffold to improve the treatment efficiency of UC-MSCs for ovarian aging under both physiological and pathological conditions, and the therapeutic mechanism is through activation of the PI3K-AKT pathway via HGF. These findings will facilitate the clinical application of MSCs transplantation for ovarian disorders.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02724-3.

Stem Cell Therapies for Human Infertility: Advantages and Challenges

Physical and mental health and hormonal imbalance are associated with the problems related to infertility and reproductive disorders. The rate of infertility has increased globally over the years, due to various reasons. Given the psychosocial implications of infertility and its effects on the life of the affected people, there has been an increased focus on its treatment over the last several years. Assisted reproductive technology can only solve about 50% of the cases. Moreover, it contains significant risks and does not solve the fundamental problem of infertility. As pluripotent stem cells have the potential to differentiate into almost any type of cell, they have been widely regarded as a promising option in the development of stem cell-based fertility treatments, which could even correct genetic diseases in offspring. These advancements in reproductive biotechnology present both challenges and possibilities for solving infertility problems caused by various unexplainable factors. This review briefly presents the different types of infertility disorders and the potential applications of stem cells in the treatment of these reproductive diseases.

Research Progress on the Treatment of Premature Ovarian Failure Using Mesenchymal Stem Cells: A Literature Review

Premature ovarian failure (POF) has become one of the main causes of infertility in women of childbearing age and the incidence of POF is increasing year by year, seriously affecting the physical and mental health of patients and increasing the economic burden on families and society as a whole. The etiology and pathogenesis of POF are complex and not very clear at present. Currently, hormone replacement therapy is mainly used to improve the symptoms of low estrogen, but cannot fundamentally solve the fertility problem. In recent years, stem cell (SC) transplantation has become one of the research hotspots in the treatment of POF. The results from animal experiments bring hope for the recovery of ovarian function and fertility in patients with POF. In this article, we searched the published literature between 2000 and 2020 from the PubMed database (https://pubmed.ncbi.nlm.nih.gov), and summarized the preclinical research data and possible therapeutic mechanism of mesenchymal stem cells (MSCs) in the treatment of POF. Our aim is to provide useful information for understanding POF and reference for follow-up research and treatment of POF.

Making More Womb: Clinical Perspectives Supporting the Development and Utilization of Mesenchymal Stem Cell Therapy for Endometrial Regeneration and Infertility

The uterus is a homeostatic organ, unwavering in the setting of monthly endometrial turnover, placental invasion, and parturition. In response to ovarian steroid hormones, the endometrium autologously prepares for embryo implantation and in its absence will shed and regenerate. Dysfunctional endometrial repair and regeneration may present clinically with infertility and abnormal menses. Asherman's syndrome is characterized by intrauterine adhesions and atrophic endometrium, which often impacts fertility. Clinical management of infertility associated with abnormal endometrium represents a significant challenge. Endometrial mesenchymal stem cells (MSC) occupy a perivascular niche and contain regenerative and immunomodulatory properties. Given these characteristics, mesenchymal stem cells of endometrial and non-endometrial origin (bone marrow, adipose, placental) have been investigated for therapeutic purposes. Local administration of human MSC in animal models of endometrial injury reduces collagen deposition, improves angiogenesis, decreases inflammation, and improves fertility. Small clinical studies of autologous MSC administration in infertile women with Asherman's Syndrome suggested their potential to restore endometrial function as evidenced by increased endometrial thickness, decreased adhesions, and fertility. The objective of this review is to highlight translational and clinical studies investigating the use of MSC for endometrial dysfunction and infertility and to summarize the current state of the art in this promising area.

Mesenchymal stem cells therapy: A promising method for the treatment of uterine scars and premature ovarian failure

Both intrauterine adhesions (IUA) and premature ovarian failure (POF) have plagued women all over the world for a long time. It is well known that all invasive operations involving the uterus can disrupt its structural and functional integrity to a varying degree, which inevitably lead to abnormal scar formation, such as IUA, also known as Asherman's syndrome with symptoms like hypomenorrhea or infertility. Another reproductive disorder that causes infertility is primary ovarian insufficiency (POI) or POF, which is a degenerative phenomenon in the ovary among women under the age of 40. In recent years, various types of stem cells, especially mesenchymal stem cells (MSCs) have been widely used in reproductive medicine due to their properties, such as immunoregulation, anti-inflammation, angiogenesis, anti-apoptosis, and trophicity. However, the extensive clinical application of cell therapy is impeded by their safety, cost, and manufacturing. In this review, we sought to summarize the recent advances in using different types of MSCs in treating uterine scars and POF. We also describe several biological pathways and molecules involved in animal studies and clinical application; extracellular vesicles secreted by MSCs may be a promising attractive tool to ensure the treatment of infertility by restoring normal reproductive function.

Human adipose-derived stromal cells transplantation prolongs reproductive lifespan on mouse models of mild and severe premature ovarian insufficiency

Background

Although recent studies have investigated the ability of Mesenchymal Stromal Cells (MSCs) to alleviate short-term ovarian damage in animal models of chemotherapy-induced Premature Ovarian Insufficiency (POI), no data are available on reproductive lifespan recovery, especially in a severe POI condition. For this reason, we investigated the potential of MSCs isolated from human adipose tissue (hASCs), since they are easy to harvest and abundant, in ameliorating the length and performance of reproductive life in both mild and severe chemotherapy-induced murine POI models.

Methods

Mild and severe POI models were established by intraperitoneally administering a light (12 mg/kg busulfan + 120 mg/kg cyclophosphamide) or heavy (30 mg/kg busulfan + 120 mg/kg cyclophosphamide) dose of chemotherapy, respectively, in CD1 mice. In both cases, a week later, 1 × 10⁶ hASCs were transplanted systemically through the tail vein. After four additional weeks, some females were sacrificed to collect ovaries for morphological evaluation. H&E staining was performed to assess stroma alteration and to count follicle numbers; immunofluorescence staining for αSMA was used to analyse vascularization. Of the remaining females, some were mated after superovulation to collect 2-cell embryos in order to evaluate their pre-implantation developmental capacity in vitro, while others were naturally mated to monitor litters and reproductive lifespan length. F1 litters’ weight, ovaries and reproductive lifespan were also analysed.

Results

hASC transplantation alleviated ovarian weight loss and size decrease and reduced alterations on ovarian stroma and vasculature, concurrently preventing the progressive follicle stockpile depletion caused by chemotherapy. These effects were associated with the preservation of the oocyte competence to develop into blastocyst in vitro and, more interestingly, with a significant decrease of chemotherapy-induced POI features, like shortness of reproductive lifespan, reduced number of litters and longer time to plug (the latter only presented in the severe POI model).

Conclusion

Human ASC transplantation was able to significantly reduce all the alterations induced by the chemotherapeutic treatment, while improving oocyte quality and prolonging reproductive functions, thus counteracting infertility. These results, strengthened by the use of an outbred model, support the potential applications of hASCs in women with POI, nowadays mainly induced by anticancer therapies.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02590-5.

The Role of Stem Cells and Their Derived Extracellular Vesicles in Restoring Female and Male Fertility

Infertility is a globally recognized issue caused by different reproductive disorders. To date, various therapeutic approaches to restore fertility have been attempted including etiology-specific medication, hormonal therapies, surgical excisions, and assisted reproductive technologies. Although these approaches produce results, however, fertility restoration is not achieved in all cases. Advances in using stem cell (SC) therapy hold a great promise for treating infertile patients due to their abilities to self-renew, differentiate, and produce different paracrine factors to regenerate the damaged or injured cells and replenish the affected germ cells. Furthermore, SCs secrete extracellular vesicles (EVs) containing biologically active molecules including nucleic acids, lipids, and proteins. EVs are involved in various physiological and pathological processes and show promising non-cellular therapeutic uses to combat infertility. Several studies have indicated that SCs and/or their derived EVs transplantation plays a crucial role in the regeneration of different segments of the reproductive system, oocyte production, and initiation of sperm production. However, available evidence triggers the need to testify the efficacy of SC transplantation or EVs injection in resolving the infertility issues of the human population. In this review, we highlight the recent literature covering the issues of infertility in females and males, with a special focus on the possible treatments by stem cells or their derived EVs.

Pathways and factors regulated by bone marrow-derived stem cells in human ovarian tissue

OBJECTIVE

To describe molecular and paracrine signaling changes produced by human bone marrow-derived stem cells (BMDSC) in human ovarian cortex.

DESIGN

Experimental study.

SETTING

University hospital research laboratories.

PATIENT(S)

Ovarian cortex from poor responder women (n = 7).

ANIMALS

Immunodeficient NOD/SCID female mice (n = 18).

INTERVENTION(S)

Human ovarian cortex strips were xenografted into ovariectomized NOD/SCID female mice. A week later, mice were infused with phosphate-buffered saline, 1 × 106 BMDSC, or 3 × 105 CD133+ cells via tail vein. Gene expression changes and enriched pathways were assessed by RT2 Profiler Arrays. Several upregulated genes were validated in individual samples by real-time quantitative PCR, and transcriptomic results were reinforced by a proteomic assessment.

MAIN OUTCOME MEASURE(S)

Gene expression changes, enriched Kyoto Encyclopedia of Genes and Genomes pathways, and paracrine factors.

RESULT(S)

Seventy-four Kyoto Encyclopedia of Genes and Genomes pathways were upregulated, with the PI3K-Akt signaling pathway the most enriched after BMDSC and CD133 treatments. The greatest transcriptomic changes were seen on day 14 in the BMDSC group, affecting the regulation of paracrine factors such as KITLG, THBS1, SERPINF1, and TIMP2. Proteomics data verified changes in FoxO signaling, actin cytoskeleton remodeling, and apoptosis by BMDSC.

CONCLUSION(S)

We identified paracrine factors and pathways regulated by BMDSC that may be future targets of treatment for the increasing number of poor responder women. Our findings suggest that BMDSC upregulated soluble factors such as KITLG, THBS1, SERPINF1, and TIMP2 as well as PI3K-Akt signaling and regulation of actin cytoskeleton pathways. The identification of these putative underlying mechanisms informs future experiments aiming to optimizing clinical application of BMDSC.

Adipose-Derived Mesenchymal Stem Cells: A Promising Tool in the Treatment of pre mature ovarian failure

Despite being rare, primary ovarian insufficiency (POI) is a significant cause of infertility and deficiency of ovarian hormone in women. Several health risks are also associated with POI, which include dry eye syndrome, reduced density of bones and enhanced fracture risks, troublesome menopausal symptoms, early development of cardiovascular disease, and psychological effects such as declined cognition, reduced perceived psychological support, anxiety, and depression. Replacing premenopausal levels of ovarian sex steroids through proper hormone replacement therapy could improve the quality of life for POI women and ameliorate related health risks. Herein, POI and its complications, in addition to hormone replacement therapies, which are safe and effective, are discussed. It is proposed that the use of HRT) Hormone replacement therapy (formulations which mimic normal production of ovarian hormones could reduce POI-associated morbidity rates if they are continued by the age 50, which is approximately the natural age of menopause. Particular populations of POI women are also addressed, which include those with enhanced risk of ovarian or breast cancer, those with Turner syndrome, those approaching natural menopause, and those who are breastfeeding. It is generally predicted that stem cell-based therapies would be both safe and effective. In fact, several types of cells have been described as safe, though their effectiveness and therapeutic application are yet to be defined. Several factors exist which could affect the results of treatment, such as cell handling, ex-vivo preparation strategies, variations in tissue of origin, potency, and immunocompatibility. Accordingly, cell types potentially effective in regenerative medicine could be recognized. Notably, products of MSCs from various sources of tissues show different levels of regenerative capabilities. The ultimate focus of the review is on adipose tissue-derive MCSs (ADMSCs), which possess exceptional features such as general availability, great ability to proliferate and differentiate, immunomodulatory capabilities, and low immunogenicity.

Adipose-Derived Mesenchymal Stem Cell Transplantation in Chemotherapy-Induced Premature Ovarian Insufficiency: the Role of Connexin and Pannexin

In women undergoing chemotherapy, it is inevitable that infertility risk will increase because of impaired reproductive functions. Premature ovarian insufficiency (POI), which occurs as a devastating result of chemotherapy, is the complete depletion or dysfunction of ovarian follicles. Adipose-derived mesenchymal stem cells (ADMSCs) transplantation is among the alternative treatment methods for POI, which currently do not have an effective treatment method. Apoptosis of granulosa cells in POI is seen as the main mechanism of the disease. It is also reported that in addition to molecules directly associated with apoptosis, connexins, and pannexins are also potential effector molecules in apoptosis. The roles of these molecules in POI, which are known to play a role in many important mechanisms in the ovary, are unknown. In this study, it was aimed to analyze the expressions of Connexin43 and Pannexin1, which are thought to be effective in the formation of POI, and to show the relationship between the antiapoptotic effects of ADMSCs transplantation and these molecules in POI. For this purpose, Caspase3, Connexin43, Pannexin1 proteins, and mRNA expressions were analyzed by immunohistochemistry and RT-qPCR, and AMH levels were measured by ELISA. It was determined that Pannexin1, Caspase3 proteins, and mRNA levels increased in the POI, while Pannexin1 and Caspase3 expressions decreased in the ADMSCs treated group. While Connexin43 level decreased in POI, Connexin43 protein and mRNA levels increased in ADMSCs group. Consequently, this study demonstrated for the first time that Connexin43 and Pannexin1 were associated with apoptosis in POI. In addition, it was revealed that ADMSCs transplantation could produce antiapoptotic effects by modulating these molecules.

Mesenchymal Stem Cells in Premature Ovarian Insufficiency: Mechanisms and Prospects

Premature ovarian insufficiency (POI) is a complex endocrine disease that severely affects the physiological and reproductive functions of females. The current conventional clinical treatment methods for POI are characterized by several side effects, and most do not effectively restore the physiological functions of the ovaries. Transplantation of mesenchymal stem cells (MSCs) is a promising regenerative medicine approach, which has received significant attention in the management of POI with high efficacy. Associated pre-clinical and clinical trials are also proceeding orderly. However, the therapeutic mechanisms underlying the MSCs-based treatment are complex and have not been fully elucidated. In brief, proliferation, apoptosis, immunization, autophagy, oxidative stress, and fibrosis of ovarian cells are modulated through paracrine effects after migration of MSCs to the injured ovary. This review summarizes therapeutic mechanisms of MSCs-based treatments in POI and explores their therapeutic potential in clinical practice. Therefore, this review will provide a theoretical basis for further research and clinical application of MSCs in POI.

Cellular therapy for myocardial ischemia using a temperature-responsive biodegradable injectable polymer system with adipose-derived stem cells

Adipose-derived stem cell (AdSC) has been attracting attention as a convenient stem cell source. Not only AdSC can differentiate into various tissue cells, but it can also accelerate cell proliferation, anti-inflammation, and angiogenesis by secreting paracrine factors. Studies have demonstrated AdSC treatment of ischemic heart. However, an improvement in the remaining live AdSCs administered at the injected site while maintaining paracrine factor secretion is desired to achieve effective regenerative medicine. We previously reported the ABA-type tri-block copolymer of poly(ɛ-caprolactone-co-glycolic acid) and poly(ethylene glycol) (tri-PCG), exhibiting temperature-responsive sol-to-gel transition as biodegradable injectable polymer (IP) systems. Moreover, we recently reported that the biodegradable temperature-triggered chemically cross-linked gelation systems exhibited longer gel state durations using tri-PCG attaching acryloyl groups and a polythiol derivative. In this study, we explored this IP-mediated AdSC delivery system. We investigated the cell viability, mRNA expression, and cytokine secretion of AdSCs cultured in the physical or chemical IP hydrogels. Both of these IP hydrogels retained a certain number of viable cells, and RT-PCR and ELISA analyses revealed that mRNA expression and secretion of vascular endothelial growth factor of the AdSCs cultured in the chemical hydrogel were higher than the physical hydrogel. Moreover, AdSCs injected with the chemical hydrogel into ischemic heart model mice showed longer retention of the cells at the injected site and recovery from the ischemic condition. The results mean that the IP system is a promising candidate for a stem cell delivery system that exhibits the recovery of cardiac function for myocardial infarction treatment.

In vitro Immunomodulatory Effects of Human Umbilical Cord-Derived Mesenchymal Stem Cells on Peripheral Blood Cells from Warm Autoimmune Hemolytic Anemia Patients

INTRODUCTION

Autoimmune hemolytic anemia is a potentially lethal disease characterized by autoimmune hemolysis. Although human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have been reported as a promising therapy, there is limited evidence regarding warm autoimmune hemolytic anemia (wAIHA) patients. This study aimed to investigate the potential therapeutic effects of hUC-MSCs via immune regulation in wAIHA patients.

METHODS

Peripheral blood mononuclear cells (PBMCs) from 10 wAIHA patients and 8 healthy controls were isolated from peripheral blood and cultured for 3 days with or without the presence of hUC-MSCs; PBMCs were co-cultured with hUC-MSCs using Transwell assays. The supernatant cytokine levels were measured after culture through AimPlex Multiple Immunoassays for Flow, including IL-2, IL-4, IL-10, IFN-γ, TNF-α, and IL-17A. The percentages of regulatory T cells, regulatory B cells, and Th1/Th2 in PBMCs were also assessed before and after culturing.

RESULTS

In the wAIHA group, hUC-MSCs could upregulate the Treg and Breg proportions after culturing for 3 days, and the Treg and Breg percentages increased after co-culturing with hUC-MSCs in the wAIHA group compared with PBMC cultured alone for 3 days (8.29 ± 8.59 vs. 6.82 ± 1.32, 3.82 ± 1.87 vs. 1.75 ± 1.20, respectively). Compared with the PBMC wAIHA group, the levels of TNF-α (2.13 ± 2.07 vs. 16.20 ± 21.13 pg/mL, p = 0.019) and IL-10 (10.51 ± 18.42 vs. 37.78 ± 44.20 pg/mL, p = 0.012) were significantly elevated in the PBMC + hUC-MSCs wAIHA group.

CONCLUSION

The hUC-MSCs contributed to the increasing proportion of regulatory cell populations in PBMCs of wAIHA patients, thereby potentially regulating autoimmune response; thus, hUC-MSCs may be a promising approach for wAIHA treatment.

Novel Approaches in Addressing Ovarian Insufficiency in 2019: Are We There Yet?

Ovarian insufficiency is described as a multifaceted issue typically encountered in the field of assisted reproduction. The three main identified diagnoses of ovarian insufficiency include premature ovarian failure (POF), poor ovarian response (POR), and advanced maternal age (AMA). Patient heterogeneity in the era of individualized medicine drives research forward leading to the emergence of novel approaches. This plethora of innovative treatments in the service of adequately managing ovarian insufficiency is called to undertake the challenge of addressing infertile patients exploring their reproductive options. This review provides an all-inclusive presentation and critical analysis on novel treatments that have not achieved routine clinical practice status yet, but have recently emerged as promising. In light of the lack of randomized controlled trials conveying safety and efficiency, clinicians are left puzzled in addressing the "how" and "for whom" these approaches may be beneficial. From ovarian injection employing platelet-rich plasma (PRP) or stem cells to artificial gametes and ovaries, ovarian transplantation, and mitochondrial replacement therapy, this descriptive review provides insight toward assisting the practitioner in decision making regarding these cutting-edge treatments. Biological mechanisms, invasiveness levels, efficiency, as well as possible complications, the current status along with bioethical concerns are discussed in the context of identifying future optimal treatment.

Application of Stem Cell Therapy for Infertility

Infertility creates an immense impact on the psychosocial wellbeing of affected couples, leading to poor quality of life. Infertility is now considered to be a global health issue affecting approximately 15% of couples worldwide. It may arise from factors related to the male (30%), including varicocele, undescended testes, testicular cancer, and azoospermia; the female (30%), including premature ovarian failure and uterine disorders; or both partners (30%). With the recent advancement in assisted reproduction technology (ART), many affected couples (80%) could find a solution. However, a substantial number of couples cannot conceive even after ART. Stem cells are now increasingly being investigated as promising alternative therapeutics in translational research of regenerative medicine. Tremendous headway has been made to understand the biology and function of stem cells. Considering the minimum ethical concern and easily available abundant resources, extensive research is being conducted on induced pluripotent stem cells (iPSCs) and mesenchymal stem cells (MSC) for their potential application in reproductive medicine, especially in cases of infertility resulting from azoospermia and premature ovarian insufficiency. However, most of these investigations have been carried out in animal models. Evolutionary divergence observed in pluripotency among animals and humans requires caution when extrapolating the data obtained from murine models to safely apply them to clinical applications in humans. Hence, more clinical trials based on larger populations need to be carried out to investigate the relevance of stem cell therapy, including its safety and efficacy, in translational infertility medicine.