Overexpression of Oct4 in porcine ovarian stem/stromal cells enhances differentiation of oocyte-like cells in vitro and ovarian follicular formation in vivo

Fertility Preservation in BRCA1/2 Germline Mutation Carriers: An Overview

BRCA1 and BRCA2 mutations are responsible for a higher incidence of breast and ovarian cancer (from 55% up to 70% vs. 12% in the general population). If their functions have been widely investigated in the onset of these malignancies, still little is known about their role in fertility impairment. Cancer patients treated with antineoplastic drugs can be susceptible to their gonadotoxicity and, in women, some of them can induce apoptotic program in premature ovarian follicles, progressive depletion of ovarian reserve and, consequently, cancer treatment-related infertility (CTRI). BRCA variants seem to be associated with early infertility, thus accelerating treatment impairment of ovaries and making women face the concrete possibility of an early pregnancy. In this regard, fertility preservation (FP) procedures should be discussed in oncofertility counseling-from the first line of prevention with risk-reducing salpingo-oophorectomy (RRSO) to the new experimental ovarian stem cells (OSCs) model as a new way to obtain in vitro-differentiated oocytes, several techniques may represent a valid option to BRCA-mutated patients. In this review, we revisit knowledge about BRCA involvement in lower fertility, pregnancy feasibility, and the fertility preservation (FP) options available.

Embryonic stem cell differentiation to primordial germ cell like cells by Nigella sativa, Brassica Oleracea and Oenothera biennis extracts

OBJECTIVES

This study aimed to investigate the induction effects of methanolic extracts of Nigella sativa (NiS), Brassica Oleracea (BrO), and Oenothera biennia (Obi) on transgenic embryonic stem cells (ESCs) and to evaluate the ability of germ cells (GCs) production using these pluripotent cells.

METHODS

ESCs were amplified using a feeder layer. Embryoid bodies enzymatically dissociated to single cells and induced the extracts in gelatinized plates. Then RNA extraction and cDNA synthesis were performed. In the presence of appropriate primers, the desired genes were quantitatively evaluated by quantitative polymerase chain reaction (qPCR).

RESULTS

The copies of all genes in the control group showed a decreasing trend during the first to third weeks. Compared to the control group, the expression level of sex determining region Y-box 2 gene (Sox2) showed the highest level. All four evaluated genes increased in all Obi groups compared to the control group. There is also a slight increase in the Nanog homeobox gene (Nanog). Obi extract in different concentrations has increased the expression of the Sox2 gene. Increased expression of this gene along with octamer-binding transcription factor 4 gene (Oct4) and Nanog indicates a condition close to germ cell-like cells (GCLCs).

CONCLUSIONS

According to the results of this study, NiS can increase expression of the Oct4, Sox2, Nanog, and stimulated by retinoic acid gene 8 (STRA8) genes and so increase the hope of GCs production. Storage of cells for 21 days in the presence of the extract compared to 14 days has a negative effect on cell growth and differentiation. The effects of meiosis onset and GCs production can be expected in the presence of some herbal extracts. Optimal utilization of these extracts requires further study in the field of different extracts and fractions of each extract to more effectively and purposefully direct the differentiation of stem cells.

A Docosahexaenoic Acid Derivative (N-Benzyl Docosahexaenamide) as a Potential Therapeutic Candidate for Treatment of Ovarian Injury in the Mouse Model

Commonly used clinical chemotherapy drugs, such as cyclophosphamide (CTX), may cause injury to the ovaries. Hormone therapies can reduce the ovarian injury risk; however, they do not achieve the desired effect and have obvious side effects. Therefore, it is necessary to find a potential therapeutic candidate for ovarian injury after chemotherapy. N-Benzyl docosahexaenamide (NB-DHA) is a docosahexaenoic acid derivative. It was recently identified as the specific macamide with a high degree of unsaturation in maca (Lepidium meyenii). In this study, the purified NB-DHA was administered intragastrically to the mice with CTX-induced ovarian injury at three dose levels. Blood and tissue samples were collected to assess the regulation of NB-DHA on ovarian function. The results indicated that NB-DHA was effective in improving the disorder of estrous cycle, and the CTX+NB-H group can be recovered to normal levels. NB-DHA also significantly increased the number of primordial follicles, especially in the CTX+NB-M and CTX+NB-H groups. Follicle-stimulating hormone and luteinizing hormone levels in all treatment groups and estradiol levels in the CTX+NB-H group returned to normal. mRNA expression of ovarian development-related genes was positive regulated. The proportion of granulosa cell apoptosis decreased significantly, especially in the CTX+NB-H group. The expression of anti-Müllerian hormone and follicle-stimulating hormone receptor significantly increased in ovarian tissues after NB-DHA treatment. NB-DHA may be a promising agent for treating ovarian injury.

Human Granulosa Cells-Stemness Properties, Molecular Cross-Talk and Follicular Angiogenesis

The ovarian follicle is the basic functional unit of the ovary, comprising theca cells and granulosa cells (GCs). Two different types of GCs, mural GCs and cumulus cells (CCs), serve different functions during folliculogenesis. Mural GCs produce oestrogen during the follicular phase and progesterone after ovulation, while CCs surround the oocyte tightly and form the cumulus oophurus and corona radiata inner cell layer. CCs are also engaged in bi-directional metabolite exchange with the oocyte, as they form gap-junctions, which are crucial for both the oocyte’s proper maturation and GC proliferation. However, the function of both GCs and CCs is dependent on proper follicular angiogenesis. Aside from participating in complex molecular interplay with the oocyte, the ovarian follicular cells exhibit stem-like properties, characteristic of mesenchymal stem cells (MSCs). Both GCs and CCs remain under the influence of various miRNAs, and some of them may contribute to polycystic ovary syndrome (PCOS) or premature ovarian insufficiency (POI) occurrence. Considering increasing female fertility problems worldwide, it is of interest to develop new strategies enhancing assisted reproductive techniques. Therefore, it is important to carefully consider GCs as ovarian stem cells in terms of the cellular features and molecular pathways involved in their development and interactions as well as outline their possible application in translational medicine.

Mesenchymal stromal/stem cells and their exosomes for restoration of spermatogenesis in non-obstructive azoospermia: a systemic review

Stem cells have been introduced as new promising therapeutic agents in treatment of degenerative diseases because of having high differentiation potential while maintaining the ability to self-replicate and retaining features of their source cells. Among different type of cell therapies, mesenchymal stromal/stem cell (MSC) therapy is being increasingly developed as a new way to treat structural defects that need to be repaired and regenerated. Non-obstructive azoospermia (NOA) is a reproductive disease in men that causes infertility in 10% of infertile men. Based on in vitro studies, MSCs from different tissue sources have been differentiated into germ cells or gamete progenitor cells by simple methods in both male and female. On the other hand, the therapeutic effects of MSCs have been evaluated for the treatment of NOA animal models created by chemical or surgical compounds. The results of these studies confirmed successful allotransplantation or xenotransplantation of MSCs in the seminiferous tubules. As well, it has been reported that exosomes secreted by MSCs are able to induce the process of spermatogenesis in the testes of infertile animal models. Despite numerous advances in the treatment of reproductive diseases in men and women with the help of MSCs or their exosomes, no clinical trial has been terminated on the treatment of NOA. This systematic review attempts to investigate the possibility of MSC therapy for NOA in men.

Evaluating differentiation potential of the human menstrual blood-derived stem cells from infertile women into oocyte-like cells

One of the most intricate infertility problems among women is the number and quality of the oocytes. Menstrual blood-derived stem cells (MenSCs) are a recently discovered source of mesenchymal stem cells which is known as a suitable source of cells for regenerative medicine. We aimed to investigate whether MenSCs as autologous cell source from endometriosis, PCOS, and healthy women have different characteristics regarding their morphology, CD marker expression pattern, differentiation potential into oocyte-like cells, and oocyte-related genes expression. Menstrual blood samples (1-2 ml) from healthy and infertile women (PCOS and endometriosis) in the age range of 22-35 years were collected. Isolated MenSCs by the Ficoll-Paque density-gradient centrifugation method was characterized by flow cytometry. MenSCs were induced under 20 % follicular fluid (FF), and then they were evaluated for differentiation by Real time-PCR and immunocytochemistry assay. MenSCs derived from endometriosis women had different morphology from PCOS and healthy women, but similar regarding their CD marker pattern. All induced MenSCs showed morphological changes and expressed oocyte related genes (STELLA, GDF9, STRA8, PRDM, LHR, FSHR, SCP3, DDX4, and ZP2) in the 2nd week of culture, but there was a significant difference between the groups. Endometriosis-derived MenSCs showed higher levels of both gene and protein expressions. These findings propose that MenSCs derived from endometriosis and PCOS patients under 20 % FF, not only could differentiate into oocyte-like cells, but also showed more differential potential in comparison with healthy women. This indicates the possibility of using the patients' own MenSCs to differentiate into the oocyte-like cells.

Effectiveness of Stem Cell Therapy in the Treatment of Ovarian Disorders and Female Infertility: A Systematic Review

BACKGROUND

Infertility is a major problem worldwide. Various strategies are being used to develop better treatments for infertility and The most trending strategy is the stem cell therapy. In this study, the literature on stem cell therapy for ovarian disorders is summarized with analysis of current developments.

OBJECTIVE

Different published studies on stem cell-based therapy for the treatment of various types of ovarian insufficiency and disorders such as Premature Ovarian Insufficiency (POI) in the affected female population in animal or human clinical studies are systematically reviewed.

METHODS

We monitored five databases, including PubMed, Cochrane, Embase, Scopus, and ProQuest. A comprehensive online search was done using the criteria targeting the application of stem cells in animal models for menopause. Two independent reviewers carefully evaluated titles and abstracts of studies. The stem cell type, source, dosage, route of administration were highlighted in various POI animals models. Non-relevant and review articles were excluded.

OUTCOMES

648 published studies were identified during the initial comprehensive search process from which 41 were selected according to designed criteria. Based on our analysis, stem cells could accelerate ovarian tissues rejuvenation, regulate systemic sex-related hormones levels and eventually increase fertility rate.

CONCLUSION

The evidence suggests that stem cell-based therapies could be considered as an alternative modality to deal with women undergoing POI.

In Vitro Generation of Oocyte Like Cells and Their In Vivo Efficacy: How Far We have been Succeeded

In the last few decades, stem cell therapy has grown as a boon for many pathological complications including female reproductive disorders. In this review, a brief description of available strategies that are related to stem cell-based in vitro oocyte-like cell (OLC) development are given. We have tried to cover all the aspects and latest updates of the in vitro OLC developmental methodologies, marker profiling, available disease models, and in vivo efficacies, with a special focus on mesenchymal stem cells (MSCs), induced pluripotent stem cells (iPSCs), and embryonic stem cells (ESCs) usage. The differentiation abilities of both the ovarian and non-ovarian stem cell sources under various induction conditions have shown different effects on morphological alterations, proliferation- and size-associated developments, hormonal secretions under gonadotropic stimulations, and their neo-oogenesis or folliculogenesis abilities after in vivo transplantations. The attainment of characters like oocyte-like morphology, size expansion, and meiosis initiation have been found to be major obstacles during in vitro oogenesis. A number of reports have either lacked in vivo studies or have shown their functional incapability to produce viable and healthy offspring. Though researchers have gained many valuable insights regarding in vitro gametogenesis, still there are many things to do to make stem cell-derived OLCs fully functional.

Human amniotic mesenchymal stem cells improve the follicular microenvironment to recover ovarian function in premature ovarian failure mice

BACKGROUND

Many adult women younger than 40 years old have premature ovarian failure (POF) and infertility. Previous studies confirmed that different tissue-derived stem cells could restore ovarian function and folliculogenesis in chemotherapy-induced POF mice. The aim of this study was to explore the therapeutic efficacy and underlying mechanisms of human amniotic mesenchymal stem cells (hAMSCs) transplantation for hydrogen peroxide-induced ovarian damage.

METHODS

Bilateral ovaries of female mice were burned with 10% hydrogen peroxide to establish a POF model. After 24 h of treatment, hAMSCs and diethylstilbestrol were administered to POF mice by intraperitoneal injection and intragastric administration, respectively. After either 7 or 14 days, ovarian function was evaluated by the oestrus cycle, hormone levels, ovarian index, fertility rate, and ovarian morphology. The karyotype was identified in offspring by the G-banding technique. hAMSCs tracking, immunohistochemical staining, and real-time polymerase chain reaction (PCR) were used to assess the molecular mechanisms of injury and repair.

RESULTS

The oestrus cycle was recovered after hAMSCs transplantation at 7 and 14 days. Oestrogen levels increased, while follicle-stimulating hormone levels decreased. The ovarian index, fertility rate, and population of follicles at different stages were significantly increased. The newborn mice had no obvious deformity and showed normal growth and development. The normal offspring mice were also fertile. The tracking of hAMSCs revealed that they colonized in the ovarian stroma. Immunohistochemical and PCR analyses indicated that changes in proteins and genes might affect mature follicle formation.

CONCLUSIONS

These results suggested that hAMSCs transplantation can improve injured ovarian tissue structure and function in oxidatively damaged POF mice. Furthermore, the mechanisms of hAMSCs are related to promoting follicular development, granulosa cell proliferation, and secretion function by improving the local microenvironment of the ovary.

Functional Testing of Primitive Oocyte-like Cells Developed in Ovarian Surface Epithelium Cell Culture from Small VSEL-like Stem Cells: Can They Be Fertilized One Day?

Data from the literature show that there are different populations of stem cells present in human adult ovaries, including small stem cells resembling very small embryonic-like stem cells (VSELs). These small ovarian stem cells with diameters of up to 5 μm are present in the ovarian surface epithelium and can grow into bigger, primitive oocyte-like cells that express several markers of a germinal lineage and exhibit pluripotency but not the zona pellucida structure when cultured in vitro. In this report, we present the results of the functional testing of such primitive oocyte-like cells from one patient with premature ovarian failure after insemination with her partners' sperm. Knowing that even immature oocytes collected in an in vitro fertilization program cannot be fertilized naturally, we were only interested in determining whether and how these cells react to added sperm and whether spermatozoa somehow "recognize" them. Interestingly, the primitive oocyte-like cells quickly released a zona pellucida-like structure in the presence of sperm. Two different populations of cells were distinguished, those with a thick and those with a thin zona pellucida-like structure. The primitive oocyte-like cells with a released zona pellucida-like structure expressed the pluripotency-related gene OCT4A (POU5F1) and zona pellucida-related gene ZP3, similar to oocytes obtained from in vitro fertilization but not somatic chondrocytes. In a small proportion of these cells, a single-spermatozoon was observed inside the cytoplasm, but no signs of fertilization were found. These observations may suggest a primitive "cortical reaction". Our data further confirm the presence of germinal stem cells in the ovarian surface epithelium cell culture.

Comparative transcriptome analysis of diploid and triploid hybrid groupers (Epinephelus coioides♀ × E. lanceolatus♂) reveals the mechanism of abnormal gonadal development in triploid hybrids

In our previous studies, diploid and triploid hybrids have been detected from the hybridization of Epinephelus coioides♀ × E. lanceolatus♂. The triploid groupers have been found to be delayed in gonadal development, but the mechanism remains poorly understood. In this study, we examined the gonadal development, assayed the serum steroid hormone levels, and compared the BP (brain and pituitary) and G (gonad) transcriptomes of 18-month-old diploid and triploid hybrids. The results showed that levels of serum estradiol-17β and testosterone were significantly higher in triploid groupers. The RNA-seq data revealed that 1518 and 14,963 differentially expressed genes were identified in the BP and G transcriptome, respectively. Further analysis revealed that the expression levels of genes involved in the sexual differentiation pathway and sex steroid synthesis pathway are significantly higher in triploid hybrids. Our findings provided a comprehensive insight into a better understanding of the regulatory mechanisms of sterility in triploid hybrid fish.

Three-dimensional wet-electrospun poly(lactic acid)/multi-wall carbon nanotubes scaffold induces differentiation of human menstrual blood-derived stem cells into germ-like cells

Infertility caused by the disruption or absence of germ cells is a major and largely incurable medical problem. Germ cells (i.e., sperm or egg) play a key role in the transmission of genetic and epigenetic information across generations. Generation of gametes derived in vitro from stem cells hold promising prospects which could potentially help infertile men and women. Menstrual blood-derived stem cells are a unique stem cell source. Evidence suggests that menstrual blood-derived stem cells exhibit a multi-lineage potential and have attracted extensive attention in regenerative medicine. To maintain the three-dimensional structure of natural extra cellular matrices in vitro, scaffolds can do this favor and mimic a microenvironment for cell proliferation and differentiation. According to previous studies, poly(lactic acid) and multi-wall carbon nanotubes have been introduced as novel and promising biomaterials for the proliferation and differentiation of stem cells. Some cell types have been successfully grown on a matrix containing carbon nanotubes in tissue engineering but there is no report for this material to support stem cells differentiation into germ cells lineage. This study designed a 3D wet-electrospun poly(lactic acid) and poly(lactic acid)/multi-wall carbon nanotubes composite scaffold to compare infiltration, proliferation, and differentiation potential of menstrual blood-derived stem cells toward germ cell lineage with 2D culture. Our primary data revealed that the fabricated scaffold has mechanical and biological suitable qualities for supporting and attachments of stem cells. The differentiated menstrual blood-derived stem cells tracking in scaffolds using scanning electron microscopy confirmed cell attachment, aggregation, and distribution on the porous scaffold. Based on the differentiation assay by RT-PCR analysis, stem cells and germ-like cells markers were expressed in 3D groups as well as 2D one. It seems that poly(lactic acid)/multi-wall carbon nanotubes scaffold-seeded menstrual blood-derived stem cells could be viewed as a novel, safe, and accessible construct for these cells, as they enhance germ-like generation from menstrual blood-derived stem cells.

Putative germline and pluripotent stem cells in adult mouse ovary and their in vitro differentiation potential into oocyte-like and somatic cells

According to classical knowledge of reproductive biology, in the ovary of female mammals there is a limited number of oocytes and there is no possibility of renewal if the oocytes are lost due to disease or injury. However, in recent years, the results of some studies on renewal and formation of oocytes and follicles in the adult mammalian ovary have led to the questioning of this opinion. The aim of our study is to demonstrate the presence of putative germline and pluripotent stem cells in the adult mouse ovary and their differentiation potential into germ and somatic cells. In ovary tissues and cells harvested from pre-differentiation step, the expression of pluripotent and germline stem cell markers was analysed by reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence staining and western blotting. Embryoid bodies that formed in this step were analysed using immunofluorescence staining and transmission electron microscopy. Ovarian stem cells were induced to differentiate into oocyte, osteoblast, chondrocyte and neural cells. Besides morphological observation, differentiated cells were analysed by RT-PCR, histochemical and immunofluorescence staining. Expression of germline and pluripotent stem cell markers both in mRNA and at the protein level were detected in the pre-differentiated cells and ovary tissues. As a result of the differentiation process, the formation of oocyte-like cells, osteoblasts, chondrocytes and neural cells was observed and characteristics of differentiated cells were confirmed using the methods mentioned above. Our study results revealed that the adult mouse ovary contains germline and pluripotent stem cells with the capacity to differentiate into oocyte-like cells, osteoblasts, chondrocytes and neural cells.

Differentiation of Mouse Primordial Germ Cells into Functional Oocytes In Vitro

Various complex molecular events in oogenesis cannot be observed in vivo. As a bioengineering technique for female reproductive tissues, in vitro culture systems for female germ cells have been used to analyze oogenesis and preserve germ cells for over 20 years. Recently, we have established a new methodological approach for the culture of primordial germ cells (PGCs) and successfully obtained offspring. Our PGC culture system will be useful to clarify unresolved mechanisms of fertility and sterility from the beginning of mammalian oogenesis, before meiosis. This review summarizes the history of culture methods for mammalian germ cells, our current in vitro system, and future prospects for the culture of germ cells.

Differentiation of human menstrual blood-derived endometrial mesenchymal stem cells into oocyte-like cells

Human endometrial mesenchymal stem cells (EnSCs) derived from menstrual blood are a unique stem cell source. Evidence suggests that EnSCs exhibit a multi-lineage potential and have attracted extensive attention in regenerative medicine. However, the potential of EnSCs to differentiate into germline cells in vitro remains unclear. In this study, EnSCs were induced to differentiate into germ cells in a differentiation medium supplemented with 20% human follicular fluid. Our results demonstrated that EnSCs derived from human menstrual blood form oocyte-like cells and express germ cell markers. The induced cell aggregates contained not only oocyte-like structures but also cells expressing follicle stimulating hormone receptor and luteotropic hormone receptor, and produced estrogen and progesterone regulated by gonodatropin, suggesting that granulosa-like and theca-like cells were also induced. We further found that granulosa cells promote the development of oocyte-like cells and activate the induction of blastocyst-like structures derived from EnSCs. In conclusion, EnSCs may potentially represent an in vitro system for the investigation of human folliculogenesis.