Human Umbilical Cord Mesenchymal Stem Cells Improve Ovarian Function in Chemotherapy-Induced Premature Ovarian Failure Mice Through Inhibiting Apoptosis and Inflammation via a Paracrine Mechanism

Investigating the differential therapeutic efficacy and mechanisms of human umbilical cord mesenchymal stem cells at various passages in osteoarthritis treatment

This study aimed to assess the clinical efficacy of umbilical cord mesenchymal stem cells (hUC-MSCs) from different passages (P3, P8, and P13) in the treatment of knee osteoarthritis (OA) and explore the underlying mechanisms. The hUC-MSCs from each passage were characterized and evaluated for their stemness, migration, proliferation, and marker expression. Rats with OA were treated with hUC-MSCs from each passage, and the therapeutic effects were assessed based on knee swelling, discomfort, and pathological examination of the knee joint. Co-culture experiments were conducted to examine the ability of hUC-MSCs to stimulate type II collagen synthesis and inhibit MMP13 expression in chondrocytes. Telomere length and telomerase activity of hUC-MSCs from each passage were measured to investigate the reasons for the observed differences in clinical efficacy. The results revealed that P3 and P8 hUC-MSCs exhibited superior osteogenic and chondrogenic differentiation potential compared to P13, while P13 demonstrated stronger adipogenic differentiation. The wound healing rate was significantly higher in the P3 and P8 groups compared to P13. All hUC-MSC groups expressed high levels of CD90 and CD105, indicating their mesenchymal stem cell characteristics, while CD31 and CD45 were not expressed. CD105 expression was significantly reduced in the P13 group. In the treatment of rat osteoarthritis, there were no significant differences in knee swelling, discomfort, Mankin scores, and pathological findings between P3 and P8 hUC-MSC treatments. However, there was a significant difference between the 8th and 13th passages. Co-culture experiments showed that hUC-MSCs from P3 and P8 enhanced type II collagen synthesis and reduced MMP13 expression in chondrocytes. Although no significant difference was observed between the P3 and P8 groups, a significant difference was found between the P13 and P8 groups. Telomere length analysis revealed that P13 samples had significantly shorter telomeres compared to both P3 and P8. The telomerase activity was positive in P3 and P8 hUC-MSCs, indicating no significant difference between these passages, while it was negative in P13 hUC-MSCs. In conclusion, P3 and P8 hUC-MSCs exhibited superior therapeutic potential for knee osteoarthritis compared to P13, possibly due to their enhanced differentiation capacity and telomerase activity.

Plasma-derived exosome miR-10a-5p promotes premature ovarian failure by target BDNF via the TrkB/Akt/mTOR signaling pathway

Premature ovarian failure (POF) is characterized by a significant decline in the ovarian follicle pool and oocyte reserve, alongside an increase in the number of low-quality oocytes and apoptosis of granulosa cells (GCs). Exosome-derived miRNA plays a regulatory role in crucial cellular activities and contributes to the onset and progression of POF. In this study, we successfully established a rabbit model of POF and conducted in vitro and in vivo experiments that confirmed DiI-labeled Pla-Exos (exosomes derived from plasma) could enter the follicle through blood circulation, with GCs capable of uptaking these exosomes. Our RNA-seq analysis revealed elevated expression of miR-10a-5p in Pla-Exos from POF rabbits. Moreover, our findings demonstrate that exosomal miR-10a-5p suppresses GCs proliferation and induces apoptosis via the mitochondrial pathway. Additionally, exosomal miR-10a-5p inhibits the TrkB/Akt/mTOR signaling pathway by downregulating BDNF expression, thereby modulating the expression levels of proteins and genes associated with the cell cycle, follicle development, and GCs senescence. In conclusion, our study highlights the role of Pla-Exos miR-10a-5p in promoting rabbit POF through the TrkB/Akt/mTOR signaling pathway by targeting BDNF. These findings provide new insights into potential therapeutic targets for POF, offering valuable references for addressing concerns related to female reproductive function.

Potential mechanisms and therapeutic strategies for LPS-associated female fertility decline

As a major component of the outer membrane of Gram-negative bacteria, lipopolysaccharide (LPS) can be recognized by toll-like receptors (TLRs) and induce inflammation through MyD88 or the TIR domain-containing adapter-inducing interferon-β (TRIF) pathway. Previous studies have found that LPS-associated inflammatory/immune challenges were associated with ovarian dysfunction and reduced female fertility. However, the etiology and pathogenesis of female fertility decline associated with LPS are currently complex and multifaceted. In this review, PubMed was used to search for references on LPS and fertility decline so as to elucidate the potential mechanisms of LPS-associated female fertility decline and summarize therapeutic strategies that may improve LPS-associated fertility decline.

Discovery and evaluation of novel spiroheterocyclic protective agents via a SIRT1 upregulation mechanism in cisplatin-induced premature ovarian failure

Currently, no effective treatment exists for premature ovarian failure (POF). To obtain compounds with protective effects against POF, we aimed to design and synthesize a series of spiroheterocyclic protective agents with a focus on minimizing toxicity while enhancing their protective effect against cisplatin-induced POF. This was achieved through systematic modifications of Michael receptors and linkers within the molecular structure of 1,5-diphenylpenta-1,4-dien-3-one analogs. To assess the cytotoxicity and activity of these compounds, we constructed quantitative conformational relationship models using an artificial intelligence random forest algorithm, resulting in R2 values exceeding 0.87. Among these compounds, j2 exhibited optimal protective activity. It significantly increased the survival of cisplatin-injured ovarian granulosa KGN cells, improved post-injury cell morphology, reduced apoptosis, and enhanced cellular estradiol (E2) levels. Subsequent investigations revealed that j2 may exert its protective effect via a novel mechanism involving the activation of the SIRT1/AKT signal pathway. Furthermore, in cisplatin-injured POF in rats, j2 was effective in increasing body, ovarian, and uterine weights, elevating the number of follicles at all levels in the ovary, improving ovarian and uterine structures, and increasing serum E2 levels in rats with cisplatin-injured POF. In conclusion, this study introduces a promising compound j2 and a novel target SIRT1 with substantial protective activity against cisplatin-induced 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.

Strategies and Challenges of Mesenchymal Stem Cells-Derived Extracellular Vesicles in Infertility

Having genetically related offspring remains an unattainable dream for couples with reproductive failure. Mesenchymal stem cells (MSCs) are multipotent stromal cells derived from various human tissues and organs. As critical paracrine effectors of MSCs, extracellular vesicles (EVs) can carry and deliver bioactive content, thereby participating in intercellular communication and determining cell fate. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have shown promising therapeutic effects, including repairing injured endometria, restoration of ovarian functions, and improving sperm quantity, morphology, and motility, owing to their regenerative potential, abundant sources, high proliferation rates, low immunogenicity, and lack of ethical issues. However, limited knowledge on purification and isolation of MSC-EVs, therapeutic effects, and unpredictable safety have caused challenges in overcoming female and male infertility. To overcome them, future studies should focus on modification/engineering of MSC-EVs with therapeutic biomolecules and combining attractive biomaterials and MSC-EVs. This review highlights the latest studies on MSC-EVs therapies in infertility and the major challenges that must be overcome before clinical translation.

Beneficial effects of human umbilical cord mesenchymal stem cell (HUCMSC) transplantation on cyclophosphamide (CTX)-induced premature ovarian failure (POF) in Tibetan miniature pigs

BACKGROUND

Premature ovarian failure (POF), also known as primary ovarian insufficiency, is a common endocrine disease in young women. The emergence of regenerative medicine using stem cells may improve ovarian function and structure, and represents a promising prospect for POF treatment. In his study, we explored the therapeutic effects of human umbilical cord mesenchymal stem cell (HUCMSC) transplantation in a Tibetan miniature pig model of cyclophosphamide (CTX)-induced POF.

METHODS

We cultured and identified HUCMSCs, labeled them with DiR iodide red dye, and implanted them into a CTX-induced model of POF in Tibetan miniature pigs. The daily weight changes were recorded, and the levels of estradiol (E2) and follicle-stimulating hormone (FSH) were measured on days 0, 7, and 14. At the end of the 21-day observation period, in vivo imaging of the bilateral ovaries was performed, and the ovarian index was measured. Ovarian tissue morphology and follicles were examined by hematoxylin-eosin staining. The terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay was employed to assess cell apoptosis, and immunohistochemistry was used to determine the levels of p-AKT, p-ERK1/2, BAX, and BCL2 expression.

RESULTS

Our analysis indicated successful delivery of HUCMSCs to the ovaries of the POF pig model. Significant increases were observed in body weight, E2 levels, ovarian index, and number of normal follicles (all p < 0.05). Moreover, FSH levels reduced and ovarian tissue morphology improved following HUCMSCs transplantation (all p < 0.05). Importantly, upregulated p-AKT, p-ERK1/2, and BCL2 expression were observed, whereas the expression of BAX was suppressed (all p < 0.05), suggesting the inhibition of ovarian cell apoptosis.

CONCLUSION

Our study highlights the significant therapeutic effects of HUCMSC transplantation on CTX-induced POF in a Tibetan miniature pig model.

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.

[Gly14]-humanin exerts a protective effect against D-galactose-induced primary ovarian insufficiency in mice

RESEARCH QUESTION

Is there a protective effect of the humanin derivative [Gly14]-humanin (HNG) on a D-gal-induced mouse model of primary ovarian insufficiency (POI), and what is the underlying mechanism?

DESIGN

D-gal (200 mg/kg/day) was injected subcutaneously for 6 weeks to induce the mouse POI model. Mice treated with HNG were injected intraperitoneally with different concentrations for 6 weeks. Ovarian morphology, function, levels of sex hormones and states of oxidative stress in the ovary and body were evaluated.

RESULTS

Compared with the D-gal group, 10 mg/kg HNG improved the abnormal ovarian morphology and oestrous cycle (P = 0.0036), increased the number of ovarian follicles (P = 0.0016) and litters (P = 0.0127), and increased the levels of oestrogen (P = 0.0043) and AMH (P = 0.0147). Antioxidant indicators in the ovaries and serum of mice, including total antioxidant capacity (P = 0.0004 and P = 0.0032, respectively), catalase (P = 0.0173 and P = 0.0103, respectively) and glutathione (both P < 0.0001) were significantly increased. The oxidation indicator malondialdehyde decreased significantly (all P < 0.01). Apoptosis of ovarian granulosa cells was significantly reduced (P = 0.0140) as was the expression of senescence-related proteins p53, p21 and p16 (all P < 0.01). The level of autophagy in ovarian tissue of mice treated with high increased (significantly increased LC3 protein [P < 0.0001] and significantly reduced p62 protein [P = 0.0007]).

CONCLUSIONS

HNG inhibited D-gal-induced oxidative stress, apoptosis and ovarian damage, promoting ovarian autophagy. HNG may be a potential prophylactic agent against 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.

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.

Potential Therapeutic Options for Premature Ovarian Insufficiency: Experimental and Clinical Evidence

Premature ovarian insufficiency (POI) is a condition in which a woman experiences premature decline in ovarian function before the age of 40 years, manifested by menstrual disorders, decreased fertility, and possibly postmenopausal symptoms such as insomnia, hot flashes, and osteoporosis, and is one of the predominant clinical syndromes leading to female infertility. Genetic, immunologic, iatrogenic and other factors, alone or in combination, have been reported to trigger POI, yet the etiology remains unknown in most cases. The main methods currently used clinically to ameliorate menopausal symptoms due to hypoestrogenemia in POI patients are hormone replacement therapy, while the primary methods available to address infertility in POI patients are oocyte donation and cryopreservation techniques, both of which have limitations to some degree. In recent years, researchers have continued to explore more efficient and safe therapies, and have achieved impressive results in preclinical trials. In this article, we will mainly review the three most popular therapies and their related signaling pathways published in the past ten years, with the aim of providing ideas for clinical applications.

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.

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.

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.

Mesenchymal stem cells therapy improves ovarian function in premature ovarian failure: a systematic review and meta-analysis based on preclinical studies

Background

Studies have revealed that the transplantation of mesenchymal stem cells (MSCs) might be a potential star candidate for premature ovarian failure (POF) in animal experiments. However, individual studies with a small sample size cannot be used to draw a clear conclusion. Therefore, we conducted a systematic review and meta-analysis to explore the potential of using MSCs in the treatment of POF in animals.

Methods

Seven databases were searched for studies exploring the effect of the transplantation of MSCs on POF in animal models. The PRISMA guideline was followed, and the methodological quality was ensured using SYRCLE's risk of bias tool. RevMan 5.4 and STATA 12.0 software was performed to meta-analysis.

Results

In total, 37 studies involving 1,079 animals were included. Significant associations were found for MSCs with the levels of E2 (SMD 2.69 [95% CI 1.97, 3.41]), FSH (-2.02, [-2.74, -1.30]), primary follicles (2.04, [1.17, 2.92]), secondary follicles (1.93, [1.05, 2.81]), and primordial follicles (2.38, [1.19, 3.57]. Other outcomes, such as AMH, LH, INHB, antral follicles, growing follicles, mature follicles, and early antral were also found to be significant. There was no difference in FSH/LH, corpus leteum, follicles, and estruc cycle.

Conclusions

Our meta-analysis result indicated that the transplantation of MSCs might exert therapeutic effects on animal models of POF, and these effects might be associated with improving the disorder of the sexual cycle, modulating serum hormone expressions to a better state, and restoring ovarian function.

Amniotic fluid-derived exosomes attenuated fibrotic changes in POI rats through modulation of the TGF-β/Smads signaling pathway

In the current study, we investigated the regenerative effects of amniotic fluid exosomes (AF-Exos) in a rat model for premature ovarian insufficiency (POI). POI is a condition characterized by a decrease in ovarian function that can lead to infertility. We induced POI by administering cyclophosphamide (CTX) for 15 consecutive days, and then transplanted AF-Exos directly into both ovarian tissues. Four weeks later, we measured the serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2), and performed histopathological evaluations using H & E and Masson's trichrome staining. We also monitored the expression of genes related to the TGF-β signaling pathway using real-time PCR and examined the fertility rate of POI rats after AF-Exos therapy. Histological analysis showed an increase in atretic follicles and a decrease in healthy follicle count after POI induction. Four weeks post-AF-Exos intervention, the healthy follicle count increased (p < 0.01) while the atretic follicle count decreased (p < 0.001). In parallel, the deposition of collagen fibers also decreased following AF-Exos transplantation. The concentrations of FSH and LH hormones in sera remained unchanged after injection of AF-Exos, while E2 levels increased (p < 0.05). The expression of Smad-4 (p < 0.01) and Smad-6 (p < 0.05) was upregulated in POI rats that received AF-Exos, while Smad-2, TGF-β1, TNF-α, and IL-10 remained statistically unchanged. Our records showed a notable increase in litter number after AF-Exos compared to the non-treated POI rats. These results suggest that AF-Exos transplantation has the potential to restore ovarian function through the TGF-β/Smads signaling pathway in POI rats.

Therapeutic prospect on umbilical cord mesenchymal stem cells in animal model with primary ovarian insufficiency: a meta-analysis

Background

Primary ovarian insufficiency (POI) leads to not only infertile but several adverse health events to women. Traditional treatment methods have their own set of limitations and drawbacks that vary in degree. Application of human umbilical cord mesenchymal stem cell (hUCMSC) is a promising strategy for POI. However, there is a lack of literatures on application of hUCMSC in human. Animal experimental model, however, can reflect the potential effectiveness of this employment. This study aimed to evaluate the curative effect of hUCMSC on animals with POI on a larger scale.

Methods

To gather data, Pubmed, Embase, and Cochrane Library were searched for studies published up to April 2022. Various indices, including the animals' estrous cycle, serum sex hormone levels, and follicle number in the ovary, were compared between the experimental group and those with Premature Ovarian Insufficiency (POI).

Results

The administration of human umbilical cord-derived mesenchymal stem cells (hUCMSC) has been shown to significantly improve the estrous cycle (RR: 3.32, 95% CI: [1.80, 6.12], I² = 0%, P = 0.0001), but robustly decrease its length (SMD: -1.97, 95% CI: [-2.58, -1.36], I² = 0%, P < 0.00001). It can also strikingly increase levels of serum estradiol (SMD: 5.34, 95% CI: [3.11, 7.57], I² = 93%, P < 0.00001) and anti-müllerian hormone (SMD: 1.92, 95% CI: [0.60, 3.25], I² = 68%, P = 0.004). Besides, it lowers levels of serum follicle-stimulating hormone (SMD: -3.02, 95% CI: [-4.88, -1.16], I² = 93%, P = 0.001) and luteinising hormone (SMD: -2.22, 95% CI: [-3.67, -0.76], I² = 78%, P = 0.003), and thus collectively promotes folliculogenesis (SMD: 4.90, 95% CI: [3.92, 5.88], I² = 0%, P < 0.00001).

Conclusions

Based on the presented findings, it is concluded that the administration of hUCMSC in animal models with POI can result in significant improvements in several key indicators, including estrous cycle recovery, hormone level modulation, and promotion of folliculogenesis. These positive outcomes suggest that hUCMSC may have potential as a treatment for POI in humans. However, further research is needed to establish the safety and efficacy of hUCMSC in humans before their clinical application.

Systematic review registration

https://inplasy.com/inplasy-2023-5-0075/, identifier: INPLASY202350075.

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.

Red Ginseng Improves D-galactose-Induced Premature Ovarian Failure in Mice Based on Network Pharmacology

In this study, we evaluated the ameliorative effect and molecular mechanism of red ginseng (Panax ginseng C.A. Meyer) extract (RGE) on D-galactose (D-gal)-induced premature ovarian failure (POF) using network pharmacology analysis. Ginsenosides are important active ingredients in ginseng, which also contains some sugar and amino acid derivatives. We aimed to determine the key proteins through which RGE regulates POF. In this work, we retrieved and screened for active ingredients in ginseng and the corresponding POF disease targets in multiple databases. A PPI network of genes was constructed in the STRING database and core targets were screened using topological analysis. Gene ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were conducted in R software. Finally, molecular docking was conducted to validate the results. Female ICR mice were used to establish a POF mouse model for in vivo experiments. Serum levels of relevant estrogens were determined using ELISA and expression levels of relevant proteins in ovarian tissues were detected using immunofluorescence and western blot analysis. Network pharmacology analysis predicted that PI3K, Akt, Bax, Bcl-2, p16, and other proteins were highly correlated with POF and RGE. The results clearly showed that RGE could increase estradiol (E2) and lower follicle-stimulating hormone (FSH) levels in D-gal-fed mice. RGE restored the expression levels of related proteins by reducing Nrf2-mediated oxidative stress, PI3K/Akt-mediated apoptosis, and senescence signaling pathways. Overall, RGE has the potential to prevent and treat POF and is likely to be a promising natural protector of the ovaries.

Vitamin D can ameliorate premature ovarian failure by inhibiting neutrophil extracellular traps: A review

The etiology of premature ovarian failure (POF) is mainly related to inflammatory diseases, autoimmune diseases, and tumor radiotherapy and chemotherapy; however, its specific pathogenesis has not been clarified. Vitamin D (VD), a fat-soluble vitamin, is an essential steroid hormone in the human body. Neutrophil extracellular traps (NETs) are meshwork structures that are formed when neutrophils are stimulated by inflammation and other factors and are closely associated with autoimmune and inflammatory diseases. Notably, VD inhibits NET formation and intervenes in the development of POF in terms of inflammatory and immune responses, oxidative stress, and tissue fibrosis. Therefore, this study aimed to theorize the relationship between NETs, VD, and POF and provide new ideas and targets for the pathogenesis and clinical treatment of POF.

Stem cell-derived extracellular vesicles: A novel and potential remedy for primary ovarian insufficiency

Primary ovarian insufficiency (POI) is an essential cause of young female fertility loss. At present, there are many treatments for primary ovarian insufficiency, but due to the complexity of the pathogenesis of primary ovarian insufficiency, the efficacy still could not be satisfactory. Stem cell transplantation is a feasible intervention protocol for primary ovarian insufficiency. However, its wide application in the clinic is limited by some defects such as tumorigenic and controversial ethical issues. Stem cell-derived extracellular vesicles (EVs) represent an important mode of intercellular communication attracting increasing interest. It is well documented that stem cell-derived extracellular vesicles for primary ovarian insufficiency with exciting therapeutic effects. Studies have found that stem cell-derived extracellular vesicles could improve ovarian reserve, increase the growth of follicles, reduce follicle atresia, and restore hormone levels of FSH and E2. Its mechanisms include inhibiting ovarian granulosa cells (GCs) apoptosis, reactive oxygen species, and inflammatory response and promoting granulosa cells proliferation and angiogenesis. Thus, stem cell-derived extracellular vesicles are a promising and potential method for primary ovarian insufficiency patients. However, stem cell-derived extracellular vesicles are still a long way from clinical translation. This review will provide an overview of the role and the mechanisms of stem cell-derived extracellular vesicles in primary ovarian insufficiency, and further elaborate on the current challenges. It may suggest new directions for future research.

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.

Mesenchymal stem cells-derived exosomes as a promising new approach for the treatment of infertility caused by polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a multifactorial metabolic and most common endocrine disorder that its prevalence, depending on different methods of evaluating PCOS traits, varies from 4% to 21%. Chronic low-grade inflammation and irregular apoptosis of granulosa cells play a crucial role in the pathogenesis of PCOS infertility. Mesenchymal stem cells (MSCs)-derived exosomes and extracellular vesicles (EVs) are lipid bilayer complexes that act as a means of intercellular transferring of proteins, lipids, DNA and different types of RNAs. It seems that this nanoparticles have therapeutic effects on the PCOS ovary such as regulating immunity response, anti-inflammatory (local and systemic) and suppress of granulosa cells (GCs) apoptosis. Although there are few studies demonstrating the effects of exosomes on PCOS and their exact mechanisms is still unknown, in the present study we reviewed the available studies of the functions of MSC-derived exosome, EVs and secretome on apoptosis of granulosa cells and inflammation in the ovary. Therefore, the novel cell-free therapeutic approaches for PCOS were suggested in this study.

Reproductive and Developmental Toxicity Assessment of Human Umbilical Cord Mesenchymal Stem Cells in Rats

Objective: Human umbilical cord mesenchymal stem cells (hUC-MSCs) have shown very attractive potential in clinical applications for the treatment of various diseases. However, the data about the reproductive and developmental toxicity of hUC-MSCs remains insufficient. Thus, we assessed the potential effects of intravenous injection of hUC-MSCs on reproduction and development in Sprague-Dawley rats. Methods: In the fertility and early embryonic development study, hUC-MSCs were administered at dose levels of 0, 6.0 × 106, 8.5 × 106, and 1.2 × 107/kg to male and female rats during the pre-mating, mating and gestation period. In the embryo-fetal development study, the pregnant female rats received 0, 6.0 × 106, 1.2 × 107, and 2.4 × 107/kg of hUC-MSCs from gestation days (GD) 6-15. Assessments made included mortality, clinical observations, body weight, food consumption, fertility parameters of male and female, litter, and fetus parameters, etc. Results: No hUC-MSCs-related toxicity was observed on the fertility of male and female rats, and no teratogenic effect on fetuses. hUC-MSCs at 1.2 × 107/kg caused a mildly decrease in body weight gain of male rats, transient listlessness, tachypnea, and hematuria symptoms in pregnant female rats. Death was observed in part of the pregnant females at a dose of 2.4 × 107/kg, which could be due to pulmonary embolism. Conclusion: Based on the results of the studies, the no-observed-adverse-effect levels (NOAELs) are 8.5 × 106/kg for fertility and early embryonic development, 1.2 × 107/kg for maternal toxicity and 2.4 × 107/kg for embryo-fetal development in rats intravenous injected with hUC-MSCs, which are equivalent to 8.5-fold, 12-fold, and 24-fold respectively of its clinical dosage in humans. These findings may provide a rational basis for human health risk assessment of hUC-MSCs.

MicroRNA-146 attenuates lipopolysaccharide induced ovarian dysfunction by inhibiting the TLR4/NF- κB signaling pathway

Premature ovarian insufficiency (POI) is a disease that seriously affects women’s reproductive function and even leads to lifelong infertility. Little is known about the mechanism of lipopolysaccharide (LPS)-induced ovarian dysfunction. Thus, we aimed to identify the role of the up-regulation of microRNA (miRNA)-146 expression offered protection against ovarian dysfunction by inhibiting the toll-like receptor (TLR) 4, TLR4/phosphorylated (p)-nuclear factor (NF)-κB signaling pathway and inflammatory cytokine tumor necrosis factor (TNF)-a and Interleukin (IL)-6. In an in vivo study, we established an LPS-induced ovarian dysfunction mouse model. The mouse ovarian granulosa cells were transfected with miR-146 mimic or negative controls or inhibitor and then treated with LPS. Therefore, cell viability, cells apoptosis, IL-6 and TNF-a, TLR4, NF- κB were assessed, respectively. These results demonstrated that the up-regulation of miRNA-146 expression may protect against LPS-induced ovarian dysfunction and markedly increased the cell viability, and significantly reduced the ovarian granulosa cells apoptotic rate, and down-regulated IL-6 and TNF-a expression. In addition, miRNA-146 exerted protective ovarian functions might be via inhibiting TLR4/NF-κB signaling pathway. In summary, we reveal the up-regulation of miRNA-146 expression mitigated ovarian dysfunction by negatively regulating expression of the IL-6 and TNF-a, which may shed light on the potential molecular mechanisms of overexpression of miRNA-146 may reversed the ovarian dysfunction by inhibiting the TLR4/ NF-κB signaling pathway.

MicroRNA-146a-5p-modified human umbilical cord mesenchymal stem cells enhance protection against diabetic nephropathy in rats through facilitating M2 macrophage polarization

Background

Diabetic nephropathy (DN) is a severe complication of diabetes mellitus and a common cause of end-stage renal disease (ESRD). Mesenchymal stem cells (MSCs) possess potent anti-inflammatory and immunomodulatory properties, which render them an attractive therapeutic tool for tissue damage and inflammation.

Methods

This study was designed to determine the protective effects and underlying mechanisms of human umbilical cord-derived MSCs (UC-MSCs) on streptozotocin-induced DN. Renal function and histological staining were used to evaluate kidney damage. RNA high-throughput sequencing on rat kidney and UCMSC-derived exosomes was used to identify the critical miRNAs. Co-cultivation of macrophage cell lines and UC-MSCs-derived conditional medium were used to assess the involvement of macrophage polarization signaling.

Results

UC-MSC administration significantly improved renal function, reduced the local and systemic inflammatory cytokine levels, and attenuated inflammatory cell infiltration into the kidney tissue in DN rats. Moreover, UC-MSCs shifted macrophage polarization from a pro-inflammatory M1 to an anti-inflammatory M2 phenotype. Mechanistically, miR-146a-5p was significantly downregulated and negatively correlated with renal injury in DN rats as determined through high-throughput RNA sequencing. Importantly, UC-MSCs-derived miR-146a-5p promoted M2 macrophage polarization by inhibiting tumor necrosis factor receptor-associated factor-6 (TRAF6)/signal transducer and activator of transcription (STAT1) signaling pathway. Furthermore, miR-146a-5p modification in UC-MSCs enhanced the efficacy of anti-inflammation and renal function improvement.

Conclusions

Collectively, our findings demonstrate that UC-MSCs-derived miR-146a-5p have the potential to restore renal function in DN rats through facilitating M2 macrophage polarization by targeting TRAF6. This would pave the way for the use of miRNA-modified cell therapy for kidney diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02855-7.

Therapeutic Role of Mesenchymal Stem Cell-Derived Extracellular Vesicles in Female Reproductive Diseases

Reproductive disorders, including intrauterine adhesion (IUA), premature ovarian insufficiency (POI), and polycystic ovary syndrome (PCOS), are great threats to female reproduction. Recently, mesenchymal stem cells derived-extracellular vesicles (MSC-EVs) have presented their potentials to cure these diseases, not only for the propensity ability they stemmed from the parent cells, but also for the higher biology stability and lower immunogenicity, compared to MSCs. EVs are lipid bilayer complexes, functional as mediators by transferring multiple molecules to recipient cells, such as proteins, microRNAs, lipids, and cytokines. EVs appeared to have a therapeutic effect on the female reproductive disorder, such as repairing injured endometrium, suppressing fibrosis of endometrium, regulating immunity and anti-inflammatory, and repressing apoptosis of granulosa cells (GCs) in ovaries. Although the underlying mechanisms of MSC-EVs have reached a consensus, several theories have been proposed, including promoting angiogenesis, regulating immunity, and reducing oxidate stress levels. In the current study, we summarized the current knowledge of functions of MSC-EVs on IUA, POI, and PCOS. Given the great potentials of MSC-EVs on reproductive health, the critical issues discussed will guide new insights in this rapidly expanding field.