Study of the reparative effects of menstrual-derived stem cells on premature ovarian failure in mice

FGF2 promotes the proliferation of injured granulosa cells in premature ovarian failure via Hippo-YAP signaling pathway

Young women undergoing anticancer treatment are at risk of premature ovarian failure (POF). Endometrial-derived stem cells (EnSCs) have demonstrated significant therapeutic potential for treating ovarian insufficiency, although the underlying mechanisms remain to be fully understood. This study aims to further investigate the therapeutic effects of EnSCs, particularly through the paracrine action of fibroblast growth factor 2 (FGF2), on POF. The findings show that exogenous FGF2 enhances the survival of ovarian granulosa cells damaged by cisplatin. FGF2 stimulates the proliferation of these damaged cells by suppressing the Hippo signaling pathway and activating YAP expression. In vivo experiments also revealed that FGF2 treatment significantly improves ovarian reserve and endocrine function in mice with POF. These results suggest that FGF2 can boost the proliferative capacity of damaged ovarian granulosa cells through the Hippo-YAP signaling pathway, providing a theoretical foundation for using EnSCs and FGF2 in clinical treatments for POF.

Ovarian microenvironment: challenges and opportunities in protecting against chemotherapy-associated ovarian damage

BACKGROUND

Chemotherapy-associated ovarian damage (CAOD) is one of the most feared short- and long-term side effects of anticancer treatment in premenopausal women. Accumulating detailed data show that different chemotherapy regimens can lead to disturbance of ovarian hormone levels, reduced or lost fertility, and an increased risk of early menopause. Previous studies have often focused on the direct effects of chemotherapeutic drugs on ovarian follicles, such as direct DNA damage-mediated apoptotic death and primordial follicle burnout. Emerging evidence has revealed an imbalance in the ovarian microenvironment during chemotherapy. The ovarian microenvironment provides nutritional support and transportation of signals that stimulate the growth and development of follicles, ovulation, and corpus luteum formation. The close interaction between the ovarian microenvironment and follicles can determine ovarian function. Therefore, designing novel and precise strategies to manipulate the ovarian microenvironment may be a new strategy to protect ovarian function during chemotherapy.

OBJECTIVE AND RATIONALE

This review details the changes that occur in the ovarian microenvironment during chemotherapy and emphasizes the importance of developing new therapeutics that protect ovarian function by targeting the ovarian microenvironment during chemotherapy.

SEARCH METHODS

A comprehensive review of the literature was performed by searching PubMed up to April 2024. Search terms included 'ovarian microenvironment' (ovarian extracellular matrix, ovarian stromal cells, ovarian interstitial, ovarian blood vessels, ovarian lymphatic vessels, ovarian macrophages, ovarian lymphocytes, ovarian immune cytokines, ovarian oxidative stress, ovarian reactive oxygen species, ovarian senescence cells, ovarian senescence-associated secretory phenotypes, ovarian oogonial stem cells, ovarian stem cells), terms related to ovarian function (reproductive health, fertility, infertility, fecundity, ovarian reserve, ovarian function, menopause, decreased ovarian reserve, premature ovarian insufficiency/failure), and terms related to chemotherapy (cyclophosphamide, lfosfamide, chlormethine, chlorambucil, busulfan, melphalan, procarbazine, cisplatin, doxorubicin, carboplatin, taxane, paclitaxel, docetaxel, 5-fluorouraci, vincristine, methotrexate, dactinomycin, bleomycin, mercaptopurine).

OUTCOMES

The ovarian microenvironment shows great changes during chemotherapy, inducing extracellular matrix deposition and stromal fibrosis, angiogenesis disorders, immune microenvironment disturbance, oxidative stress imbalances, ovarian stem cell exhaustion, and cell senescence, thereby lowering the quantity and quality of ovarian follicles. Several methods targeting the ovarian microenvironment have been adopted to prevent and treat CAOD, such as stem cell therapy and the use of free radical scavengers, senolytherapies, immunomodulators, and proangiogenic factors.

WIDER IMPLICATIONS

Ovarian function is determined by its 'seeds' (follicles) and 'soil' (ovarian microenvironment). The ovarian microenvironment has been reported to play a vital role in CAOD and targeting the ovarian microenvironment may present potential therapeutic approaches for CAOD. However, the relation between the ovarian microenvironment, its regulatory networks, and CAOD needs to be further studied. A better understanding of these issues could be helpful in explaining the pathogenesis of CAOD and creating innovative strategies for counteracting the effects exerted on ovarian function. Our aim is that this narrative review of CAOD will stimulate more research in this important field.

REGISTRATION NUMBER

Not applicable.

M6A demethylase FTO-stabilized exosomal circBRCA1 alleviates oxidative stress-induced granulosa cell damage via the miR-642a-5p/FOXO1 axis

BACKGROUND

Premature ovarian insufficiency (POI) is an important cause of female infertility and seriously impacts the physical and psychological health of patients. Human umbilical cord mesenchymal stem cell-derived exosomes (HucMSCs-Exs, H-Exs) have exhibited protective effects on ovarian function with unclear mechanisms.

METHODS

A comprehensive analysis of the Gene Expression Omnibus (GEO) database were used to identify POI-associated circRNAs and miRNAs. The relationship between HucMSC-derived exosomal circBRCA1/miR-642a-5p/FOXO1 axis and POI was examined by RT-qPCR, Western blotting, reactive oxygen species (ROS) staining, senescence-associated β-gal (SA-β-gal) staining, JC-1 staining, TEM, oxygen consumption rate (OCR) measurements and ATP assay in vivo and in vitro. RT-qPCR detected the expression of circBRCA1 in GCs and serum of patients with normal ovarian reserve function (n = 50) and patients with POI (n = 50); then, the correlation of circBRCA1 with ovarian reserve function indexes was analyzed.

RESULTS

Herein, we found that circBRCA1 was decreased in the serum and ovarian granulosa cells (GCs) of patients with POI and was associated with decreased ovarian reserve. H-Exs improved the disorder of the estrous cycles and reproductive hormone levels, reduced the number of atretic follicles, and alleviated the apoptosis and senescence of GCs in rats with POI. Moreover, H-Exs mitigated mitochondrial damage and reversed the reduced circBRCA1 expression induced by oxidative stress in GCs. Mechanistically, FTO served as an eraser to increase the stability and expression of circBRCA1 by mediating the m6A demethylation of circBRCA1, and exosomal circBRCA1 sponged miR-642a-5p to block its interaction with FOXO1. CircBRCA1 insufficiency aggravated mitochondrial dysfunction, mimicking FTO or FOXO1 depletion effects, which was counteracted by miR-642a-5p inhibition.

CONCLUSION

H-Exs secreted circBRCA1 regulated by m6A modification, directly sponged miR-642a-5p to upregulate FOXO1, resisted oxidative stress injuries in GCs and protected ovarian function in rats with POI. Exosomal circBRCA1 supplementation may be a general prospect for the prevention and treatment of POI.

The Effect of Human Umbilical Cord Mesenchymal Stem Cell on Premature Ovarian Cell Senilism Through miR-10a

Objective

To investigate the potential protective impact of miR-10a-modified HUMSCs-derived exosomes on both premature ovarian failure and the functionality of ovarian granulosa cells in a POF model.

Methods

KGN cells were co-cultured with cisplatin-diaminedichloroplatinum (II) (10 μM) for 24 h to establish an in vitro POF model. The cells were distributed into three distinct groups: the control group, the POF group, and the POF + HUCMSC group. The plasmid sh-NC, sh-miR-10 a and miR-10 a mimic were transfected into KGN cells. After co-cultured with HUCMSC-EVs for 48 h, they were divided into HUCMSC group, sh-miR-10 a-HUMSCs-exosomes group and miR-10 a-HUMSCs-exosomes group. Flow cytometry was adopted to assess the impact of HUMSCs surface immune antigens and miR-10a-HUCMSCs-exosomes on KGN cell apoptosis. Additionally, the evaluation of cell proliferation was carried out through CCK-8 and EDU assays. Western blot analysis was utilized to detect the Caspase-3, Bax, and Bcl-2 proteins levels. Furthermore, the levels of TNF-α, IL-6, IL-10, MDA, SOD, and CAT were quantified using ELISA.

Results

Compared with the Control group, the POF group inhibited the growth of ovarian granulosa cells (P<0.01), reduced the number of EDU cells (P<0.01), and increased the protein expression of Caspase-3 (P<0.05) and Bax (P<0.01). HUMSCs treatment significantly down-regulated the expression of IL-6, TNF-α and MDA, while up-regulating the expression of IL-10, SOD and CAT (P<0.01); the overexpression of miR-10a promoted cell growth, besides, the introduction of miR-10a-HUMSCs-derived exosomes led to an elevation in the proliferation rate of OGCs affected by POF and concurrently suppressed the apoptosis rate.

Conclusion

HUMSCs-derived exosomes modified by miR-10a have protective effects on premature ovarian failure and ovarian granulosa cell function in POF model.

Endometrial stem cell-derived exosomes repair cisplatin-induced premature ovarian failure via Hippo signaling pathway

Stem cells have been documented as a new therapeutic method for ovarian injuries such as premature ovarian failure (POF). However, effects of exosomes (Exos) derived from human endometrial stem cells (EnSCs) on diminished ovarian failure remain to be carefully elucidated. Our study aims to investigate the mechanisms of EnSC-Exos in the recovery of the cisplatin-induced granulosa cell injury model in vitro or POF mouses model in vivo and whether the Hippo signaling pathway is involved in the regulation. In this study, we established successful construction of the cisplatin-induced granulosa cell injury model and evaluated Hippo signaling pathway activation in cisplatin-damaged granulosa cells (GCs). Furthermore, laser scanning confocal microscope and immunofluorescence demonstrated that EnSC-Exos can be transferred to cisplatin-damaged GCs to decrease apoptosis. In addition, the enhanced expression of YAP at the protein level as well as YAP/TEAD target genes, such as CTGF, ANKRD1, and the increase of YAP into the nucleus in immunofluorescence staining after the addition of EnSC-Exos to cisplatin-damaged GCs confirmed the suppression of Hippo signaling pathway. While in vivo, EnSC-Exos successfully remedied POF in a mouse model. Collectively, our findings suggest that chemotherapy-induced POF was associated with the activating of Hippo signaling pathway. Human EnSC-Exos significantly elevated the proliferation of ovarian GCs and the ovarian function by regulating Hippo signaling pathway. These findings provide new insights for further understanding of EnSC-Exos in the recovery of ovary function.

Endometrial stem cells alleviate cisplatin-induced ferroptosis of granulosa cells by regulating Nrf2 expression

BACKGROUND

Premature ovarian failure (POF) caused by cisplatin is a severe and intractable sequela for young women with cancer who received chemotherapy. Cisplatin causes the dysfunction of granulosa cells and mainly leads to but is not limited to its apoptosis and autophagy. Ferroptosis has been also reported to participate, while little is known about it. Our previous experiment has demonstrated that endometrial stem cells (EnSCs) can repair cisplatin-injured granulosa cells. However, it is still unclear whether EnSCs can play a repair role by acting on ferroptosis.

METHODS

Western blotting and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) were applied to detect the expression levels of ferroptosis-related genes. CCK-8 and 5-Ethynyl-2'-deoxyuridine (EdU) assays were used to evaluate cell viability. Transmission electron microscopy (TEM) was performed to detect ferroptosis in morphology. And the extent of ferroptosis was assessed by ROS, GPx, GSSG and MDA indicators. In vivo, ovarian morphology was presented by HE staining and the protein expression in ovarian tissue was detected by immunohistochemistry.

RESULTS

Our results showed that ferroptosis could occur in cisplatin-injured granulosa cells. Ferroptosis inhibitor ferrostatin-1 (Fer-1) and EnSCs partly restored cell viability and mitigated the damage of cisplatin to granulosa cells by inhibiting ferroptosis. Moreover, the repair potential of EnSCs can be markedly blocked by ML385.

CONCLUSION

Our study demonstrated that cisplatin could induce ferroptosis in granulosa cells, while EnSCs could inhibit ferroptosis and thus exert repair effects on the cisplatin-induced injury model both in vivo and in vitro. Meanwhile, Nrf2 was validated to participate in this regulatory process and played an essential role.

Efficient and scalable gene delivery method with easily generated cationic carbon dots

Gene delivery is a complex process with several challenges when attempting to incorporate genetic material efficiently and safely into target cells. Some of the key challenges include not only efficient cellular uptake and endosomal escape to ensure that the genetic material can exert its effect but also minimizing the toxicity of the delivery system, which is vital for safe gene delivery. Of importance, if gene delivery systems are intended for biomedical applications or clinical use, they must be scalable and easy and affordable to manufacture to meet the demand. Here, we show an efficient gene delivery method using a combination of carbon dots coated by PEI through electrostatic binding to easily generate cationic carbon dots. We show a biofunctional approach to generate optimal cationic carbon dots (CCDs) that can be scaled up to meet specific transfection demands. CCDs improve cell viability and increase transfection efficiency four times over the standard of PEI polyplexes. Generated CCDs enabled the challenging transfection protocol to produce retroviral vectors via cell cotransfection of three different plasmids into packing cells, showing not only high efficiency but also functionality of the gene delivery, tested as the capacity to produce infective retroviral particles.

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 cell therapy for premature ovarian insufficiency: a systematic review and meta-analysis of animal and clinical studies

PURPOSE

The aim of this systematic review and meta-analysis is to evaluate the efficacy of stem cell therapy in mouse models of POI and patients with POI.

METHODS

The PubMed, Web of Science, and Embase databases were searched from inception to February 2022 for relevant animal and clinical studies. The reference lists of the included reviews were manually searched to identify additional eligible studies. Data were independently extracted by two investigators, and disagreements were resolved by discussion. SYRCLE's risk of bias tool and the MINORS tool were used to assess the quality of animal and clinical studies by two independent investigators. All statistical analyses were conducted using Review Manager 5.3 software.

RESULTS

A total of twenty animal studies and six clinical studies were included in this meta-analysis. In animal studies, the results showed that stem cells could improve hormone levels, follicle count, estrous cycle and pregnancy outcome. For hormone levels, stem cells increased serum E2 and AMH levels and decreased serum FSH and LH levels compared with the control group (serum E2 level: SMD: 5.05, 95% CI 4.21-5.90, P < 0.00001; serum AMH level: SMD: 4.42, 95% CI 3.06-5.79, P < 0.00001; serum FSH level: SMD: - 3.79, 95% CI - 4.87 to -  2.70, P < 0.00001; serum LH level: SMD: - 1.31, 95% CI - 1.65 to - 0.96, P < 0.00001). All follicle counts, except for the antral follicle count, were significantly changed compared with the control group. (primordial follicle count: SMD: 4.61, 95% CI 3.65-5.56, P < 0.00001; primary follicle count: SMD: 3.35, 95% CI 1.08-5.63, P = 0.004; secondary follicle count: SMD: 3.23, 95% CI 1.92-4.55, P < 0.00001; total follicle count: SMD: 4.84, 95% CI 2.86-6.83, P < 0.00001; oocyte count: SMD: 7.56, 95% CI 5.92-9.20, P < 0.00001; atretic follicle count: SMD: - 1.79, 95% CI - 2.59 to - 1.00, P < 0.00001). For the estrous cycle, stem cell therapy increased the number of estrous cycles (WMD: 2.72, 95% CI 2.07-3.37, P < 0.00001) and decreased the duration of the estrous cycle (WMD: - 1.26, 95% CI - 1.84 to - 0.69, P < 0.0001) compared with the control group. For pregnancy outcomes, stem cell therapy increased the fertility rate (RR: 3.00, 95% CI 1.74-5.17, P < 0.0001) and litter size (WMD: 3.82, 95% CI 0.36-7.28, P = 0.03) compared with the control group. In animal studies, the asymmetric funnel plot of serum E2 and FSH levels indicated the possibility of publication bias. Unpublished and negative studies may be the source of publication bias. In clinical studies, the results showed that stem cell therapy could decrease serum FSH level (MD: - 30.32, 95% CI - 59.03 to - 1.01, P = 0.04) and increase AFC (MD: 1.07, 95% CI 0.70-1.43, P < 0.00001), pregnancy rate (RD: 0.19, 95% CI 0.04-0.34, P = 0.01) and live birth rate (RD: 0.19, 95% CI 0.07-0.31, P = 0.001) in POI patients. In addition, there was no significant difference in menstrual function regained (RD: 0.22, 95% CI - 0.03-0.46, P = 0.09), oocytes retrieved (MD: 1.00, 95% CI - 0.64-2.64, P = 0.23) and embryos (MD: 0.80, 95% CI - 0.15-1.76, P = 0.10) between different groups.

CONCLUSION

This meta-analysis suggested that stem cell therapy might be effective in POI mouse models and patients and could be considered a potential treatment to restore fertility capability in POI patients.

LncRNA HOTAIR regulates autophagy and proliferation mechanisms in premature ovarian insufficiency through the miR-148b-3p/ATG14 axis

Premature ovarian insufficiency (POI) is a serious disease significantly affecting the physical and mental health of women of reproductive age, not just impacting fertility outcomes. Ovarian damage due to chemotherapy remains a major cause of this condition. Recent studies have indicated the involvement of the long non-coding RNA HOTAIR in the progression of various diseases, showcasing important biological functions, yet its role in POI remains unclear. We conducted microarray dataset analysis and qRT-PCR experiments, demonstrating downregulation of HOTAIR expression in ovarian tissue and granulosa cells. Various functional experiments using plasmids overexpressing HOTAIR confirmed its promotion of cisplatin-induced granulosa cell autophagy and proliferation. Mechanistically, dual-luciferase assays showed that HOTAIR modulates ATG14 levels in POI by binding miR-148b-3p, thereby enhancing levels of autophagy and proliferation. In this study, we first explored the impact of miR-148b-3p on POI and found that overexpression of miR-148b-3p reversed the promotion of autophagy and proliferation induced by HOTAIR overexpression. The inhibitory effect of miR-148b-3p inhibitor on KGN cell autophagy and proliferation improvement could also be reversed by silencing ATG14. Overall, our findings indicate the promoting role of HOTAIR in POI and its potential as a biomarker for POI by modulating the miR-148b-3p/ATG14 axis to improve mechanisms of autophagy and proliferation in POI.

The Concept behind the Suitability of Menstrual Blood-Derived Stem Cells for the Management of Vaginal Atrophy among BRCA Mutation Carriers after RRSO

Risk-reducing bilateral salpingo-oophorectomy (RRSO) is recommended for breast cancer gene 1 (BRCA1) and 2 (BRCA2) mutation carriers. A major consequence of RRSO is surgical menopause associated with severe menopausal symptoms, mostly genitourinary complaints. Due to the inherent breast cancer risk, estrogen-based therapies are generally avoided in these patients. So far, the non-hormonal approaches available are not efficient to successfully treat the disabling vaginal atrophy-related symptoms. In regenerative medicine, mesenchymal stem cells (MSC) are the most frequently used cell type due to their remarkable and regenerative characteristics. Therapies based on MSC have revealed positive outcomes regarding symptoms and signs associated with vaginal atrophy by promoting angiogenesis, vaginal restoration, and the proliferation of vaginal mucosa cells. Menstrual blood-derived stem cells (MenSC) are a novel source of MSC, with promising therapeutic potential directly linked to their high proliferative rates; low immunogenicity; non-invasive, easy, and periodic acquisition; and almost no associated ethical issues. In this review, we update the current knowledge and research regarding the potential value of previously preserved MenSC in the therapy of vaginal atrophy among BRCA mutation carriers subjected to RRSO.

Premature ovarian insufficiency: a review on the role of tobacco smoke, its clinical harm, and treatment

Premature ovarian insufficiency (POI) is a condition in which the quantity of follicles and the quality of oocytes gradually decrease. This results in an estrogen secretion disorder and abnormal follicle development, which can lead to related diseases, early onset of menopause, sexual dysfunction, and an increased risk of cardiovascular issues, osteoporosis, and depression, among others. This disease significantly impacts the physical and mental health and overall quality of life of affected women. Factors such as genetic abnormalities, oophorectomy, radiotherapy for malignancy, idiopathic conditions, and an unhealthy lifestyle, including smoking, can accelerate the depletion of the follicular pool and the onset of menopause. Extensive research has been conducted on the detrimental effects of tobacco smoke on the ovaries. This article aims to review the advancements in understanding the impact of tobacco smoke on POI, both in vivo and in vitro. Furthermore, we explore the potential adverse effects of common toxicants found in tobacco smoke, such as polycyclic aromatic hydrocarbons (PAHs), heavy metals like cadmium, alkaloids like nicotine and its major metabolite cotinine, benzo[a]pyrene, and aromatic amines. In addition to discussing the toxicants, this article also reviews the complications associated with POI and the current state of research and application of treatment methods. These findings will contribute to the development of more precise treatments for POI, offering theoretical support for enhancing the long-term quality of life for women affected by this condition.

MALAT1/miR-7-5p/TCF4 Axis Regulating Menstrual Blood Mesenchymal Stem Cells Improve Thin Endometrium Fertility by the Wnt Signaling Pathway

Thin endometrium (TE) is a significant factor contributing to fertility challenges, and addressing this condition remains a central challenge in reproductive medicine. Menstrual blood-derived mesenchymal stem cells (MenSCs) play a crucial role in tissue repair and regeneration, including that of TE. The Wnt signaling pathway, which is highly conserved and prevalent in eukaryotes, is essential for cell proliferation, tissue development, and reproductive functions. MALAT1 is implicated in various transcriptional and molecular functions, including cell proliferation and metastasis. However, the combined effects of the Wnt signaling pathway and the long non-coding RNA (lncRNA) MALAT1 on the regulation of MenSCs' regenerative capabilities in tissue engineering have not yet been explored. To elucidate the regulatory mechanism of MALAT1 in TE, we analyzed its expression levels in normal endometrium and TE tissues, finding that low expression of MALAT1 was associated with poor clinical prognosis. In addition, we conducted both in vitro and in vivo functional assays to examine the role of the MALAT1/miR-7-5p/TCF4 axis in cell proliferation and migration. Techniques such as dual-luciferase reporter assay, fluorescent in situ hybridization, and immunoblot experiments were utilized to clarify the molecular mechanism. To corroborate these findings, we established a TE model and conducted pregnancy experiments, demonstrating a strong association between MALAT1 expression and endometrial fertility. In conclusion, our comprehensive study provides strong evidence supporting that lncRNA MALAT1 modulates TCF4 expression in the Wnt signaling pathway through interaction with miR-7-5p, thus enhancing MenSCs-mediated improvement of TE and improving fertility.

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.

Novel therapeutic strategies for injured endometrium: intrauterine transplantation of menstrual blood‑derived cells from infertile patients

BACKGROUND

Menstrual blood-derived cells show regenerative potential as a mesenchymal stem cell and may therefore be a novel stem cell source of treatment for refractory infertility with injured endometrium. However, there have been few pre-clinical studies using cells from infertile patients, which need to be addressed before establishing an autologous transplantation. Herein, we aimed to investigate the therapeutic capacity of menstrual blood-derived cells from infertile patients on endometrial infertility.

METHODS

We collected menstrual blood-derived cells from volunteers and infertile patients and confirmed their mesenchymal stem cell phenotype by flow cytometry and induction of tri-lineage differentiation. We compared the proliferative and paracrine capacities of these cells. Furthermore, we also investigated the regenerative potential and safety concerns of the intrauterine transplantation of infertile patient-derived cells using a mouse model with mechanically injured endometrium.

RESULTS

Menstrual blood-derived cells from both infertile patients and volunteers showed phenotypic characteristics of mesenchymal stem cells. In vitro proliferative and paracrine capacities for wound healing and angiogenesis were equal for both samples. Furthermore, the transplantation of infertile patient-derived cells into uterine horns of the mouse model ameliorated endometrial thickness, prevented fibrosis, and improved fertility outcomes without any apparent complications.

CONCLUSIONS

In our pre-clinical study, intrauterine transplantation of menstrual blood-derived cells may be a novel and attractive stem cell source for the curative and prophylactic therapy for injured endometrium. Further studies will be warranted for future clinical application.

FGF2 Rescued Cisplatin-Injured Granulosa Cells through the NRF2-Autophagy Pathway

Premature ovarian failure (POF) is a complicated disorder related to the apoptosis of granulosa cells. The incidence of chemotherapy-associated POF is rising dramatically owing to the increasing proportion of cancer in adolescents. According to previous studies, oxidative stress caused by chemotherapeutic agents plays an important role in the development of POF. However, the exact effects of nuclear factor-erythroid 2-related factor2 (NRF2), a pivotal anti-oxidative factor, are still unknown in chemotherapy-associated POF. Firstly, we manipulated NRF2 expressions on a genetic or pharmaceutical level in cisplatin-injured granulosa cell models. The results indicate that the increasing NRF2 in cisplatin-injured cells was just compensatory and not enough to resist the accumulated stress. Upregulation of NRF2 could protect granulosa cells against cisplatin via elevating autophagic level by using an autophagic activator (rapamycin) and inhibitor (chloroquine). Additionally, exogenous FGF2 exerted a protective role by increasing NRF2 expression and promoting its nuclear translocation. Meanwhile, the results in cisplatin-POF mice models were consistent with what was found in injured cells. In conclusion, our research proved that FGF2 rescued cisplatin-injured granulosa cells through the NRF2-autophagy pathway and might provide a possible alternative treatment choice by targeting NRF2 for POF patients who are intolerant or unsuitable to FGF2.

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.

Exploring the future potential of mesenchymal stem/stromal cells and their derivatives to support assisted reproductive technology for female infertility applications

Women's infertility impacts the quality of life of both patients and couples and has multifaceted dimensions that increase the number of challenges associated with female infertility and how to face them. Female reproductive disorders, such as premature ovarian failure (POF), endometriosis, Asherman syndrome (AS), polycystic ovary syndrome (PCOS), and preeclampsia, can stimulate infertility. In the last decade, translational medicine has advanced, and scientists are focusing on infertility therapy with innovative attitudes. Recent investigations have suggested that stem cell treatments could be safe and effective. Stem cell therapy has established a novel method for treating women's infertility as part of a regeneration approach. The chief properties and potential of mesenchymal stem/stromal cells (MSCs) in the future of women's infertility should be considered by researchers. Due to their high abundance, great ability to self-renew, and high differentiation capacity, as well as less ethical concerns, MSC-based therapy has been found to be an effective alternative strategy to the previous methods for treating female infertility, such as intrauterine insemination, in vitro fertilization, medicines, and surgical procedures. These types of stem cells exert their beneficial role by releasing active mediators, promoting cell homing, and contributing to immune modulation. Here we first provide an overview of MSCs and their crucial roles in both biological and immunological processes. The next large chapter covers current preclinical and clinical studies on the application of MSCs to treat various female reproductive disorders. Finally, we deliberate on the extant challenges that hinder the application of MSCs in female infertility and suggest plausible measures to alleviate these impediments.

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.

Human umbilical cord mesenchymal stem cell-derived extracellular vesicles improve ovarian function in rats with primary ovarian insufficiency by carrying miR-145-5p

OBJECTIVE

Stem cell/exosome therapy is a novel strategy for primary ovarian insufficiency (POI). This paper is to examine the role of human umbilical cord mesenchymal stem cell-derived extracellular vesicles (hUCMSC-EVs) in POI.

METHODS

hUCMSC-EVs were extracted and identified. POI rats were induced by cyclophosphamide for 15 days and treated with EV or GW4869 every 5 days and euthanized 28 days later. Vaginal smears were observed for 21 days. Serum hormone levels (FSH/E2/AMH) were measured by ELISA. Ovarian morphology, follicle numbers, and granulosa cell (GC) apoptosis were observed by HE and TUNEL staining. GCs extracted from Swiss albino rats were cyclophosphamide-induced to establish the POI cell model, followed by oxidative injury and apoptosis evaluation with the help of DCF-DA fluorescence, ELISA, and flow cytometry. The relation between miR-145-5p and XBP1 was predicted on StarBase and validated by dual-luciferase assay. miR-145-5p and XBP1 levels were measured by RT-qPCR and Western blot.

RESULTS

EV treatment reduced irregular estrus cycle incidence since day 7, increased E2 and AMH levels and all-stage follicle numbers, reduced FSH level, GC apoptosis, and atretic follicle numbers in POI rats. EV treatment diminished GC oxidative injury and apoptosis in vitro. miR-145-5p knockdown in hUCMSC-EVs partly abolished hUCMSC-EV-mediated effects on GCs and ovarian function in vivo and on GC oxidative injury and apoptosis in vitro. Silencing XBP1 partially negated miR-145-5p knockdown-exerted effects on GCs in vitro.

CONCLUSION

miR-145-5p carried by hUCMSC-EVs attenuates GC oxidative injury and apoptosis and thus extenuates ovarian injury and improves ovarian function in POI rats.

Human UC-MSC-derived exosomes facilitate ovarian renovation in rats with chemotherapy-induced premature ovarian insufficiency

Premature ovarian insufficiency (POI) induced by chemotherapy is an intractable disorder with a considerable incidence that commonly results in insufficient fertility and concomitant complications in female patients. Due to limitations in the current progress in POI diagnosis and treatment, there is an urgent need to develop novel remedies to improve ovarian function and protect fertility. The ameliorative effect of human umbilical cord mesenchymal stem cells (hUCMSCs) and exosomes derived from them in POI treatment could be a new hope for patients. Herein, we identified exosomes from hUCMSCs (hUCMSC-Exos). Then, systematic infusion of hUCMSC-Exos was accomplished via tail intravenous injection to investigate the feasibility of the treatment of rats with chemotherapy-induced POI by intraperitoneal injection of cyclophosphamide (CTX) and busulfan (BUS). Ovarian functions in the indicated group were evaluated, including oestrous cycle, serum sex hormone levels, follicle counts, ovarian pathological changes, proliferation and apoptosis of granulosa cells (GCs), and reproductive ability testing. Furthermore, the potential influence of hUCMSC-Exos on ovarian tissues was illuminated by conducting RNA-seq and multifaceted bioinformatics analyses. POI rats with hUCMSC-Exos transplantation exhibited a decrease in follicle-stimulating hormone (FSH) and apoptosis of GCs but an increase in oestradiol (E2), anti-Müllerian hormone (AMH), and the number of ovarian follicles and foetuses in the uterus. And the immunomodulation- and cellular vitality-associated gene sets in rats had also undergone moderate changes. Our data indicated the feasibility of hUCMSC-Exos in improving ovarian function and protecting fertility in chemotherapy-induced POI rats. HUCMSC-Exos can improve the local microenvironment of ovarian tissue in POI rats by participating in immune regulation, cellular viability, inflammation regulation, fibrosis and metabolism, and other related signal pathways.

Comparison of the therapeutic effects between stem cells and exosomes in primary ovarian insufficiency: as promising as cells but different persistency and dosage

BACKGROUND

Primary ovarian insufficiency (POI) refers to the loss of ovarian function under the age of 40 and results in amenorrhea and infertility. Our previous studies have shown that transplantation of mesenchymal stem cells (MSCs) and MSC-derived exosomes in chemotherapy-induced POI mouse ovaries can reverse the POI and eventually achieve pregnancy. Based on our recent studies, MSC-derived exosomes have almost equal therapeutic potentials as transplanted MSCs. However, it is still unclear whether exosomes can completely replace MSCs in POI treatment. For the reliable application of cell-free treatment for POI patients using exosomes, there is a need to understand whether there is any outcome and effectiveness difference between MSC and MSC-derived exosome treatment.

METHODS

Comparing the therapeutic effect of intravenous injection using MSCs and equal amounts of exosomes in a POI mouse model will reveal the difference between the two therapeutic resources. In this study, we induced POI in C57/BL6 mice by chemotherapy (CXT) using a standard protocol. We then injected four different doses of MSCs or equal amounts of commercialized MSC-derived exosomes by retro-orbital injection post-CXT.

RESULT

After MSC/exosome treatment, tissue and serum samples were harvested to analyze molecular changes after treatment, while other mice in parallel experiments underwent breeding experiments to compare the restoration of fertility. Both the MSC- and exosome-treated groups had a restored estrous cycle and serum hormone levels compared to untreated POI mice. The pregnancy rate in the MSC-treated group was 60-100% after treatment, while the pregnancy rate in the exosome-treated group was 30-50% after treatment. Interestingly, in terms of long-term effects, MSC-treated mice still showed a 60-80% pregnancy rate in the second round of breeding, while the exosome-treated group became infertile again in the second round of breeding.

CONCLUSIONS

Although there were some differences in the efficacy between MSC treatment and exosome treatment, both treatments were able to achieve pregnancy in the POI mouse model. In conclusion, we report that MSC-derived exosomes are a promising therapeutic option to restore ovarian function in POI conditions similar to treatment with MSCs.

HGF-modified human umbilical cord mesenchymal stem cells rescue impaired ovarian reserve function in chemotherapy-induced POI rats by improving angiogenesis while decreasing apoptosis and fibrosis in the ovary

Complications caused by Primary ovarian insufficiency (POI), including infertility, osteoporosis, cardiovascular diseases and depression, severely affect the life quality of female patients. Although hormone replacement therapy (HRT) can alleviate some long-term complications, there is still no standard treatment for the restoration of ovarian reserve function. Currently, human umbilical cord mesenchymal stem cells (HUCMSC) transplantation showed considerable treatment effect for POI in both rat model and clinic. To improve the effectiveness of naïve HUCMSC (HUCMSC-Null) treatments on POI, an exogenous gene hepatocyte growth factor (HGF) which promotes follicular angiogenesis in POI ovaries was used to modify HUCMSC. Subsequently, HGF-overexpressed HUCMSC (HUCMSC-HGF) was transplanted into the ovaries of chemotherapy-induced POI Sprague-Dawley (SD) rats to observe the effectiveness on POI improvement and its related mechanisms. Our results showed that when compared with POI and HUCMSC-Null treatment group, HUCMSC-HGF significantly improved ovarian reserve function in POI group, which might be attributed to the decrease of ovarian tissue fibrosis and granulosa cells (GCs) apoptosis, and the increase of ovarian angiogenesis mediated by HGF over-expression. The findings suggest that HGF-modified HUCMSC may present a more superior capacity than HUCMSC alone for the rescue of ovarian reserve function in POI.

Comparison of the different animal modeling and therapy methods of premature ovarian failure in animal model

Incidence of premature ovarian failure (POF) is higher with the increase of the pace of life. The etiology of POF is very complex, which is closely related to genes, immune diseases, drugs, surgery, and psychological factors. Ideal animal models and evaluation indexes are essential for drug development and mechanism research. In our review, we firstly summarize the modeling methods of different POF animal models and compare their advantages and disadvantages. Recently, stem cells are widely studied for tumor treatment and tissue repair with low immunogenicity, high homing ability, high ability to divide and self-renew. Hence, we secondly reviewed recently published data on transplantation of stem cells in the POF animal model and analyzed the possible mechanism of their function. With the further insights of immunological and gene therapy, the combination of stem cells with other therapies should be actively explored to promote the treatment of POF in the future. Our article may provide guidance and insight for POF animal model selection and new drug development.

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.

The Therapeutic Potential of Human Umbilical Cord Derived Mesenchymal Stem Cells for the Treatment of Premature Ovarian Failure

Premature ovarian failure (POF) affects 1% of women under 40, leading to infertility. The clinical symptoms of the POF include hypoestrogenism, lack of mature follicles, hypergonadotropinism, and amenorrhea. POF can be caused due to genetic defects, autoimmune illnesses, and environmental factors. The conventional treatment of POF remains a limited success rate. Therefore, an innovative treatment strategy like the regeneration of premature ovaries by using human umbilical cord mesenchymal stem cells (hUC-MSCs) can be a choice. To summarize all the theoretical frameworks for additional research and clinical trials, this review article highlights all the results, pros, and cons of the hUC-MSCs used to treat POF. So far, the data shows promising results regarding the treatment of POF using hUC-MSCs. Several properties like relatively low immunogenicity, multipotency, multiple origins, affordability, convenience in production, high efficacy, and donor/recipient friendliness make hUC-MSCs a good choice for treating basic POF. It has been reported that hUC-MSCs impact and enhance all stages of injured tissue regeneration by concurrently stimulating numerous pathways in a paracrine manner, which are involved in the control of ovarian fibrosis, angiogenesis, immune system modulation, and apoptosis. Furthermore, some studies demonstrated that stem cell treatment could lead to hormone-level restoration, follicular activation, and functional restoration of the ovaries. Therefore, all the results in hand regarding the use of hUC-MSCs for the treatment of POF encourage researchers for further clinical trials, which will overcome the ongoing challenges and make this treatment strategy applicable to the clinic in the near future.

Graphical Abstract

Gender bias and menstrual blood in stem cell research: A review of pubmed articles (2008–2020)

Despite proven scientific quality of menstrual blood mesenchymal cells, research and science output using those cells is still incipient, which suggests there is a resistance to the study of this type of cell by scientists, and a lack of attention to its potential for cell therapy, regenerative medicine and bioengineering. This study analyzes the literature about the menstrual blood mesenchymal stromal/stem cells (mbMSC) on the PubMed database between 2008–2020 and the social attention it received on Twitter. A comparative analysis showed that mbMSC accounts for a very small portion of mesenchymal cell research (0.25%). Most first authors are women (53.2%), whereas most last authors are men (63.74%), reinforcing an already known, and still significant, gender gap between last and corresponding authors. Menstrual blood tends to be less used in experiments and its scientific value tends to be underestimated, which brings gender bias to a technical and molecular level. Although women are more positive in the mbMSC debate on Twitter, communication efforts toward visibility and public interest in menstrual cells has room to grow.

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.

hUMSCs Transplantation Regulates AMPK/NR4A1 Signaling Axis to Inhibit Ovarian Fibrosis in POI Rats

BACKGROUND

The mechanism of human Umbilical Cord Mesenchymal Stem Cells (hUMSCs) transplantation to improve ovarian function in the rats with Premature Ovarian Insufficiency (POI) is still unclear. The aim of this study is to investigate the signal axis mechanism that is involved in the ovarian function recovery of POI rats following hUMSCs transplantation.

METHODS

The rat model with POI was established by intraperitoneal injection of cisplatin. The hUMSCs were transplanted by caudal vein injection into POI rats. Hematoxylin-eosin (H&E) staining was performed to examine the morphology of rat ovarian tissue. Masson staining, Sirus red staining and immunofluorescence were used to observe the fibrosis extent of ovarian tissue. The levels of serum sex hormones and the expression of fibrosis related markers in ovarian tissues were measured by enzyme-linked immunosorbent assay (ELISA). The expression of NR4A1, Phospho-NR4A1 and AMP-activated protein kinase (AMPK) signaling in rat ovarian tissues was measured by immunohistochemistry and immunofluorescence. The role of AMPK/NR4A1 signaling axis in the regulation of ovarian function recovery in POI rats following hUMSCs transplantation was further investigated by adenovirus and siRNA intervention in isolated stromal cells.

RESULTS

The results showed that the hUMSCs transplantation significantly inhibited ovarian tissue fibrosis and restored the ovarian function in POI rats. The level of NR4A1 and AMPK expression in ovarian tissue of POI rats after hUMSCs transplantation was significantly increased compared with the control group. In the cultured ovarian stromal cells, the similar results were obtained on the expression of NR4A1 and its regulation on fibrosis related molecular markers in Cisplatin (CDDP) damaged stromal cells following hUMSCs supernatant treatment. Both hUMSCs supernatant treatment and the addition of AMPK inhibitors increased NR4A1 expression in stromal cells. And after NR4A1 molecular intervention, fibrosis-related indicators in stromal cells changed. The data suggests that the AMPK/NR4A1 signaling axis is involved in the ovarian function changes in POI rats following hUMSCs transplantation.

CONCLUSION

The data from this study indicate that the inhibition of tissue fibrosis and recovery of ovarian function is regulated by AMPK/NR4A1 signaling axis in POI rats following hUMSCs transplantation.

Bone marrow mesenchymal stem cells in premature ovarian failure: Mechanisms and prospects

Premature ovarian failure (POF) is a common female reproductive disorder and characterized by menopause, increased gonadotropin levels and estrogen deficiency before the age of 40 years old. The etiologies and pathogenesis of POF are not fully clear. At present, hormone replacement therapy (HRT) is the main treatment options for POF. It helps to ameliorate perimenopausal symptoms and related health risks, but can't restore ovarian function and fertility fundamentally. With the development of regenerative medicine, bone marrow mesenchymal stem cells (BMSCs) have shown great potential for the recovery of ovarian function and fertility based on the advantages of abundant sources, high capacity for self-renewal and differentiation, low immunogenicity and less ethical considerations. This systematic review aims to summarize the possible therapeutic mechanisms of BMSCs for POF. A detailed search strategy of preclinical studies and clinical trials on BMSCs and POF was performed on PubMed, MEDLINE, Web of Science and Embase database. A total of 21 studies were included in this review. Although the standardization of BMSCs need more explorations, there is no doubt that BMSCs transplantation may represent a prospective therapy for POF. It is hope to provide a theoretical basis for further research and treatment for POF.

Effects of Low-Intensity Pulsed Ultrasound on the Migration and Homing of Human Amnion-Derived Mesenchymal Stem Cells to Ovaries in Rats With Premature Ovarian Insufficiency

Premature ovarian insufficiency (POI) can cause multiple sequelae and is currently incurable. Mesenchymal stem cell (MSC) transplantation might provide an effective treatment method for POI. However, the clinical application of systemic MSC transplantation is limited by the low efficiency of cell homing to target tissue in vivo, including systemic MSC transplantation for POI treatment. Thus, exploration of methods to promote MSC homing is necessary. This study was to investigate the effects of low-intensity pulsed ultrasound (LIPUS) on the migration and homing of transplanted human amnion–derived MSCs (hAD-MSCs) to ovaries in rats with chemotherapy-induced POI. For LIPUS treatment, hAD-MSCs were exposed to LIPUS or sham irradiation. Chemokine receptor expressions in hAD-MSCs were detected by polymerase chain reaction (PCR), Western blot, and immunofluorescence assays. hAD-MSC migration was detected by wound healing and transwell migration assays. Cyclophosphamide-induced POI rat models were established to evaluate the effects of LIPUS on the homing of systemically transplanted hAD-MSCs to chemotherapy-induced POI ovaries in vivo. We found that hAD-MSCs expressed chemokine receptors. The LIPUS promoted the expression of chemokine receptors, especially CXCR4, in hAD-MSCs. SDF-1 induced hAD-MSC migration. The LIPUS promoted hAD-MSC migration induced by SDF-1 through SDF-1/CXCR4 axis. SDF-1 levels significantly increased in ovaries induced by chemotherapy in POI rats. Pretreating hAD-MSCs with LIPUS increased the number of hAD-MSCs homing to ovaries in rats with chemotherapy-induced POI to some extent. However, the difference was not significant. Both hAD-MSC and LIPUS-pretreated hAD-MSC transplantation reduced ovarian injuries and improved ovarian function in rats with chemotherapy-induced POI. CXCR4 antagonist significantly reduced the number of hAD-MSCs- and LIPUS-pretreated hAD-MSCs homing to POI ovaries, and further reduced their efficacy in POI treatment. According to these findings, pretreating MSCs with LIPUS before transplantation might provide a novel, convenient, and safe technique to explore for improving the homing of systemically transplanted MSCs to target tissue.

hUCMSCs reduce theca interstitial cells apoptosis and restore ovarian function in premature ovarian insufficiency rats through regulating NR4A1-mediated mitochondrial mechanisms

BACKGROUND

Human umbilical cord mesenchymal stem cells (hUCMSCs, retrospectively registered) have a lot of promise for treating theca interstitial cells(TICs) dysfunction in premature ovarian insufficiency (POI). The mechanisms, however, are still unknown.

METHODS

To examine the therapeutic and find the cause, we used both in vivo cisplatin-induced POI rat model and in vitro TICs model. HUCMSCs were injected into the tail veins of POI rats in an in vivo investigation. Then, using ELISA, HE staining, TUNEL apoptosis test kit, immunohistochemistry and western blot, researchers examined hormonal levels, ovarian morphology, TICs apoptosis, NR4A1 and Cyp17a1 in response to cisplatin treatment and hUCMSCs. TICs were obtained from the ovaries of rats and treated with the cisplatin, hUCMSCs supernatant, and the antagonist of NR4A1--DIM-C-pPhOH. ELISA, immunofluorescence, flow cytometry, JC-1 labeling and western blot analysis were used to detect T levels, Cyp17a1, NR4A1, and the anti-apoptotic protein Bcl-2, as well as pro-apoptotic proteins Bax, caspase-9, caspase-3, and cytochrome C(cytc).

RESULTS

We discovered that hUCMSCs restored the ovarian function, particularly TICs function based on measures of Cyp17a1 and T expression. NR4A1 was found in ovarian TICs of each group and NR4A1 expression was lower in the POI rats but higher following hUCMSCs therapy. The apoptosis of TICs generated by cisplatin was reduced after treatment with hUCMSCs. In vitro, NR4A1 was expressed in the nucleus of TICs, and NR4A1 as well as phospho-NR4A1 were decreased, following the apoptosis of TICs was emerged after cisplatin treatment. Interestingly, the localization of NR4A1 was translocated from the nucleus to the cytoplasm due to cisplatin. HUCMSCs were able to boost NR4A1 and phospho-NR4A1 expression while TICs' apoptosis and JC-1 polymorimonomor fluorescence ratios reduced. Furthermore, Bcl-2 expression dropped following cisplatin treatment, whereas Bax, cytc, caspase-9, and caspase-3 expression rose; however, hUCMSCs treatment reduced their expression. In addition, DIM-C-pPhOH had no effect on the NR4A1 expression, but it did increase the expression of apoptosis-related factors such as Bax, cytc, caspase-9, and caspase-3, causing the apoptosis of TICs.

CONCLUSIONS

These data show that hUCMSCs therapy improves ovarian function in POI rats by inhibiting TICs apoptosis through regulating NR4A1 -mediated mitochondrial mechanisms.

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.

Umbilical Cord Mesenchymal Stem Cells Ameliorate Premature Ovarian Insufficiency in Rats

Premature ovarian insufficiency (POI) or premature ovarian failure (POF) is known as a state of hypergonadotropic hypogonadism. Stem cell therapy is expected to be used in the treatment of POI. The aim of the present study was to explore the feasibility and effectiveness of umbilical cord mesenchymal stem cell (UCMSC) transplantation for the treatment of POI in a rat model of POI induced by cyclophosphamide (CTX) injection. The ovarian function was examined by evaluating the weight of the ovary and body, estrus cycle, ovarian morphology, hormonal secretion, granulosa cell apoptosis, and fertility. The results showed that the ovarian function indicators of the modeled rats were comparable to those of the control rats after UCMSC transplantation, indicating that the ovarian function of the modeled rats recovered to a satisfactory extent. Our research may provide an experimental clue for the clinical application of UCMSC transplantation in the treatment of POI. Further experiments will focus on the detailed signaling pathway study of the molecular mechanisms of injury and repairment on the treatment with UCMSCs transplantation in the rat POI models.

A decade of discovery: the stunning progress of premature ovarian insufficiency research in China

Premature ovarian insufficiency (POI) is one of key aspects of ovarian infertility. Due to early cession of ovarian function, POI imposes great challenges on the physiological and psychological health of women, and becomes a common cause of female infertility. In the worldwide, there has been a special outpouring of concern for about four million reproductive-aged women suffering from POI in China. Driven by advances in new technologies and efforts invested by Chinses researchers, understanding about POI has constantly been progressing over the past decade. Here, we comprehensively summarize and review the landmark development and achievements from POI studies in China spanning 2011 to 2020, which aims to provide key insights from bench to bedside.

Menstrual blood-derived stem cells and its mitochondrial treatment improve the ovarian condition of aged mice

Aging causes a decline in ovarian function and may contribute to ovarian failure and infertility. We investigated the effect of menstrual blood-derived mesenchymal stem cells (MenSCs) and their mitochondria on ovarian function in aged mice. We performed two treatment protocols: i) ovaries of recipient aged mice were treated in vivo with MenSCs 3D alginate gel; ii) ovaries were injected with mitochondria suspension and then incubated with mitochondrial 3D gel. Seven days after treatment, ovaries were harvested for histological assessment by HE staining and transcriptomic analysis by RNA-seq. Our data showed that after incubation with stem cell 3D gel, the MenSCs could be detected in the recipient mouse ovary. HE staining showed that the follicular state of aging ovary improved with both treatments. RNA-seq analysis showed that mitochondrial pathway-related genes were upregulated and significantly enriched in the ovaries treated by MenSCs or their mitochondria. Conclusions: Treatment with MenSCs or their mitochondria can enhance the expression of mitochondrial pathway-related genes and promote the recovery of ovarian function in aged mice.

Artificial Ovary for Young Female Breast Cancer Patients

In recent decades, there has been increasing attention toward the quality of life of breast cancer (BC) survivors. Meeting the growing expectations of fertility preservation and the generation of biological offspring remains a great challenge for these patients. Conventional strategies for fertility preservation such as oocyte and embryo cryopreservation are not suitable for prepubertal cancer patients or in patients who need immediate cancer therapy. Ovarian tissue cryopreservation (OTC) before anticancer therapy and autotransplantation is an alternative option for these specific indications but has a risk of retransplantation malignant cells. An emerging strategy to resolve these issues is by constructing an artificial ovary combined with stem cells, which can support follicle proliferation and ensure sex hormone secretion. This promising technique can meet both demands of improving the quality of life and meanwhile fulfilling their expectation of biological offspring without the risk of cancer recurrence.

FTO protects human granulosa cells from chemotherapy-induced cytotoxicity

BACKGROUND

Premature ovarian failure (POF) is a serious problem for young women who receive chemotherapy, and its pathophysiological basis is the dysfunction of granulosa cells. According to previous reports, menstrual-derived stem cells (MenSCs) can restore ovarian function and folliculogenesis in mice with chemotherapy-induced POF. Fat mass- and obesity-associated (FTO) was reported to be associated with oocyte development and maturation. FTO was decreased in POF and may be a biomarker for the occurrence of POF. Knockdown of FTO in granulosa cells promoted cell apoptosis and inhibited proliferation. But the relationship between FTO and ovarian repair was still unclear. This study was aimed at investigating the FTO expression level and the role of FTO in the MenSCs recovering the function of injured granulosa cells.

METHOD

First, cisplatin was used to establish a granulosa cell injury model. Then, the MenSCs and injured granulosa cell coculture model and POF mouse model were established in this study to explore the role of FTO. Furthermore, gain- and loss-of-function studies, small interfering RNA transfection, and meclofenamic acid (MA), a highly selective inhibitor of FTO, studies were also conducted to clarify the regulatory mechanism of FTO in granulosa cells.

RESULTS

MenSCs coculture could improve the function of injured granulosa cells by increasing the expression of FTO. MenSCs transplantation restored the expression of FTO in the ovaries of POF mice. Overexpression of FTO restored the injured cell proliferation and decreased apoptosis by regulating the expression of BNIP3. Down-regulation of FTO got the opposite results.

CONCLUSIONS

In the treatment of MenSCs, FTO has a protective effect, which could improve the viability of granulosa cells after cisplatin treatment by decreasing the expression of BNIP3. Meanwhile, FTO may provide new insight into therapeutic targets for the chemotherapy-induced POF.

Important role of the SDF-1/CXCR4 axis in the homing of systemically transplanted human amnion-derived mesenchymal stem cells (hAD-MSCs) to ovaries in rats with chemotherapy-induced premature ovarian insufficiency (POI)

Background

Chemotherapy can induce premature ovarian insufficiency (POI). POI causes multiple sequelae and is currently incurable. As shown in our previous studies, systemically transplanted human amnion-derived mesenchymal stem cells (hAD-MSCs) home to ovaries with chemotherapy-induced POI and subsequently reduce ovarian injury and improve ovarian function in rats with POI. However, the cellular mechanisms that direct the migration and homing of hAD-MSCs to ovaries with chemotherapy-induced POI are incompletely understood. This study investigated the role of the SDF-1/CXCR4 axis in the migration and homing of systemically transplanted hAD-MSCs to ovaries with chemotherapy-induced POI and its relevant downstream signalling pathways.

Methods

CXCR4 expression in hAD-MSCs was assessed using Western blotting and immunofluorescence staining. hAD-MSC migration was tested using Transwell migration assays. SDF-1 levels were detected using ELISA. Seventy-two female SD rats were randomly divided into the control, POI, hAD-MSCs and hAD-MSCs + AMD3100 groups. Cyclophosphamide was used to establish rat POI models. For inhibitor treatment, hAD-MSCs were pretreated with AMD3100 before transplantation. PKH26-labeled hAD-MSCs were injected into the tail vein of POI rats 24 h after chemotherapy. After hAD-MSC transplantation, the homing of hAD-MSCs to ovaries and ovarian function and pathological changes were examined. We further investigated the molecular mechanisms by detecting the PI3K/Akt and ERK1/2 signalling pathways.

Results

hAD-MSCs expressed CXCR4. SDF-1 induced hAD-MSC migration in vitro. SDF-1 levels in ovaries and serum were significantly increased in rats with chemotherapy-induced POI, and ovaries with POI induced the homing of hAD-MSCs expressing CXCR4. Blocking the SDF-1/CXCR4 axis with AMD3100 significantly reduced the number of hAD-MSCs homing to ovaries with POI and further reduced their efficacy in POI treatment. The binding of SDF-1 to CXCR4 activated the PI3K/Akt signalling pathway, and LY294002 significantly inhibited hAD-MSC migration induced by SDF-1 in vitro. Moreover, inhibition of the PI3K/Akt signalling pathway significantly reduced the number of systemically transplanted hAD-MSCs homing to chemotherapy-induced ovaries in rats with POI.

Conclusions

SDF-1/CXCR4 axis partially mediates the migration and homing of systemically transplanted hAD-MSCs to the ovaries of rats with chemotherapy-induced POI, and the PI3K/Akt signalling pathway might be involved in the migration and homing of hAD-MSCs mediated by the SDF-1/CXCR4 axis.

Therapeutic options for premature ovarian insufficiency: an updated review

Primary ovarian insufficiency (POI) is a rare gynecological condition. This disease causes menstrual disturbances, infertility, and various health problems. Historically, hormone replacement therapy is the first-line treatment for this disorder. Women diagnosed with POI are left with limited therapeutic options. In order to remedy this situation, a new generation of therapeutic approaches, such as in vitro activation, mitochondrial activation technique, stem cell and exosomes therapy, biomaterials strategies, and platelet-rich plasma intra-ovarian infusion, is being developed. However, these emerging therapies are yet in the experimental stage and require precise design components to accelerate their conversion into clinical treatments. Thus, each medical practitioner bears responsibility for selecting suitable therapies for individual patients. In this article, we provide a timely analysis of the therapeutic strategies that are available for POI patients and discuss the prospects of POI therapy.

Metabolic Rewiring by Human Placenta-Derived Mesenchymal Stem Cell Therapy Promotes Rejuvenation in Aged Female Rats

Aging is a degenerative process involving cell function deterioration, leading to altered metabolic pathways, increased metabolite diversity, and dysregulated metabolism. Previously, we reported that human placenta-derived mesenchymal stem cells (hPD-MSCs) have therapeutic effects on ovarian aging. This study aimed to identify hPD-MSC therapy-induced responses at the metabolite and protein levels and serum biomarker(s) of aging and/or rejuvenation. We observed weight loss after hPD-MSC therapy. Importantly, insulin-like growth factor-I (IGF-I), known prolongs healthy life spans, were markedly elevated in serum. Capillary electrophoresis-time-of-flight mass spectrometry (CE-TOF/MS) analysis identified 176 metabolites, among which the levels of 3-hydroxybutyric acid, glycocholic acid, and taurine, which are associated with health and longevity, were enhanced after hPD-MSC stimulation. Furthermore, after hPD-MSC therapy, the levels of vitamin B6 and its metabolite pyridoxal 5′-phosphate were markedly increased in the serum and liver, respectively. Interestingly, hPD-MSC therapy promoted serotonin production due to increased vitamin B6 metabolism rates. Increased liver serotonin levels after multiple-injection therapy altered the expression of mRNAs and proteins associated with hepatocyte proliferation and mitochondrial biogenesis. Changes in metabolites in circulation after hPD-MSC therapy can be used to identify biomarker(s) of aging and/or rejuvenation. In addition, serotonin is a valuable therapeutic target for reversing aging-associated liver degeneration.

FGF2 Is Protective Towards Cisplatin-Induced KGN Cell Toxicity by Promoting FTO Expression and Autophagy

It is widely known that chemotherapy-induced apoptosis of granulosa was the main reason for premature ovarian failure (POF). In addition, accumulating evidence has demonstrated that autophagy was involved in it. Studies before have reported that fibroblast growth factor-2 (FGF2) could attenuate cell death via regulating autophagy. In our previous study, FGF2 could decrease granulosa cell apoptosis in cisplatin-induced POF mice. Furthermore, obesity-associated protein [fat mass and obesity-associated protein (FTO)], which decreased significantly in POF mice, could inhibit cell apoptosis via activating autophagy. Moreover, downregulation of FTO could decrease the expression of paracrine factor FGF2. However, the relationship between FTO and FGF2 in granulosa cell autophagy is still unknown. In the present study, Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2-deoxyuridine (EdU) assays showed that exogenous addition of FGF2 could promote cisplatin-induced injured granulosa cell proliferation. Western blotting indicated that FGF2 could inhibit apoptosis of injured granulosa cells via autophagy. Inhibition of autophagy by chemicals suppressed the effect of FGF2 and promoted injured cell apoptosis. In addition, the expression of FTO was decreased in injured cells, and FGF2 addition could reverse it. Overexpression of FTO reduced injured cell apoptosis via activating the autophagy process. Our findings indicated that FGF2 activates autophagy by regulating the expression of FTO, thereby reducing the apoptosis of the injured cells.

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.

[Effect of GnRH agonist combined with menstrual blood-derived stem cell transplantation on ovarian function in mice]

OBJECTIVE

To investigate the effect of combined treatment with gonadotropin-releasing hormone (GnRH) agonist and menstrual blood-derived stem cell (MenSC) transplantation on ovarian function in mice.

METHODS

We tested the effect of GnRH agonist and MenSC transplantation, either alone or in combination, in a mouse model of premature ovarian failure (POF) induced by daily intraperitoneal injection of 120 mg/kg cyclophosphamide (CTX) for 15 days. Venirelin was administered at the daily dose of 0.1 mg via intravenous infusion, starting at 14 days before modeling; MenSC suspension (2× 106 cells) was injected into the ovarium 1 day after modeling. HE staining was used to observe ovarian pathologies of the mice. ELISA was used to detect serum levels of LH, FSH, AMH and E2. The expression levels of ki-67, Bcl-2, BAX, caspase 9, caspase 3, their cleavages, P-PI3K, PI3K, P-Akt and Akt proteins in ovarian granulosa cells were determined with Western blotting.

RESULTS

The mouse models of POF showed obvious ovarian fibrosis with increased atresia follicles and had significantly elevated serum levels of LH and FSH (P < 0.01), decreased serum levels of AMH and E2 (P < 0.01), significantly increased ovarian expression levels of caspase 9, caspase 3, and their cleavages (P < 0.01), and decreased expression levels of Ki-67, Bcl-2, P-PI3K and P-Akt (P < 0.01). The combined treatment with GnRH agonist and MenSC transplantation obviously inhibited the production of ovarian atresia follicles, lowered serum levels of LH and FSH (P < 0.01), and increased the levels of AMH and E2 (P < 0.05 or 0.01) in the mouse models. The combined treatment also inhibited the expressions of BAX and cleaved caspase 9 and caspase 3 proteins (P < 0.05 or 0.01) and enhanced the expressions of Ki-67, Bcl-2, P-PI3K, and p-Akt proteins (P < 0.05 or 0.01) in ovarian granulococcus cells.

CONCLUSION

In mouse models of POF, GnRH agonist combined with MenSC transplantation can reduce the generation of ovarian atresia and improve ovarian reserve by up-regulating PI3K-Akt signaling pathway to achieve ovarian repair and protection.

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.

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.

A stem cell-derived ovarian regenerative patch restores ovarian function and rescues fertility in rats with primary ovarian insufficiency

Rationale: Primary ovarian insufficiency (POI) normally occurs before age 40 and is associated with infertility. Hormone replacement therapy is often prescribed to treat vasomotor symptom, but it cannot restore ovarian function or fertility. Stem cell therapy has been studied for the treatment of POI. However, the application of live stem cells has suffered from drawbacks, such as low cell retention/engraftment rate, risks for tumorigenicity and immunogenicity, and lack of off-the-shelf feasibility.

Methods: We developed a therapeutic ovarian regenerative patch (ORP) that composed of clinically relevant hydrolysable scaffolds and synthetic mesenchymal stem cells (synMSCs), which are microparticles encapsulating the secretome from MSCs. The therapeutic potency of ORP was tested in rats with cisplatin induced POI injury.

Results:In vitro studies revealed that ORP stimulated proliferation of ovarian somatic cells (OSCs) and inhibited apoptosis under injury stress. In a rat model of POI, implantation of ORP rescued fertility by restoring sexual hormone secretion, estrus cycle duration, and follicle development.

Conclusion: ORP represents a cell-free, off-the-shelf, and clinically feasible treatment for POI.