Toll-like receptor4 as a modulator of fertilization and subsequent pre-implantation development following in vitro maturation in mice

Study on the expression patterns and function of JUNO and CD9 in bovine oocytes during in vitro maturation

Fertilization proteins JUNO and CD9 play vital roles in sperm-egg fusion, but little is known about their expression patterns during in vitro maturation (IVM) and their function during in vitro fertilization (IVF) of bovine oocytes. In this study, qRT-PCR and immunofluorescence staining were used to detect the mRNA and protein expression levels of JUNO and CD9 genes in bovine oocytes and cumulus cells. Then, fertilization rate of MII oocytes treated with (i) JUNO antibody (1, 5 and 25 μg/ml) or (ii) CD9 antibody (1, 5 and 25 μg/ml) or (iii) CD9 antibody (5 μg/ml) + JUNO antibody (5 μg/ml) were recorded. Our results showed that the mRNA and protein expression levels of JUNO and CD9 genes significantly increased from bovine GV oocytes to MII oocytes, and similar mRNA expression patterns of JUNO and CD9 were also detected in cumulus cells. All groups of oocytes treated with CD9 antibody or JUNO antibody showed significantly decreased fertilization rates (p < .05). Particularly, the fertilization ability of oocytes treated with CD9 antibody (5 μg/ml) + JUNO antibody (5 μg/ml) sharply decreased to 3.48 ± 0.11%. In conclusion, our study revealed the expression levels of JUNO and CD9 genes in oocytes and cumulus cells increased during IVM of bovine oocytes, with JUNO protein playing a major role in the fertilization of bovine oocytes.

Tricostatin A-treated round spermatid enhances preimplantation embryo developmental competency following round spermatid injection in mice

It has been documented that the inefficacy of round spermatid injection (ROSI) might be caused by abnormal epigenetic modifications. Therefore, this study aimed to evaluate the effect of trichostatin A (TSA) as an epigenetic modifier of preimplantation embryo development in activated ROSI oocytes. Matured oocytes were collected from superovulated female mice. Testes were placed in human tubal fluid medium and masses were then cut into small pieces to disperse spermatogenic cells. Round spermatids were treated with TSA and subsequently injected into oocytes. The expression level of the development-related genes including Oct4, Sox2, Nanog, Dnmt and Hdac transcripts were evaluated using qRT-PCR. Immunohistochemistry was performed to confirm the presence of Oct-4 protein at the blastocyst stage. There was no statistically significant difference in fertilization rate following ROSI/+TSA compared with the non-treated ROSI and intracytoplasmic sperm injection (ICSI) groups. Importantly, TSA treatment increased blastocyst formation from 38% in non-treated ROSI to 68%. The relative expression level of developmentally related genes increased and Dnmt transcripts decreased in ROSI/+TSA-derived embryos, similar to the expression levels observed in the ICSI-derived embryos. In conclusion, our results indicate that spermatid treatment with TSA prior to ROSI would increase the success rate of development to the blastocyst stage and proportion of pluripotent cells.

Contrasting effects of the Toll-like receptor 4 in determining ovarian follicle endowment and fertility in female adult mice

Toll-like receptor 4 (TLR4) is best known for its role in bacteria-produced lipopolysaccharide recognition. Regarding female reproduction, TLR4 is expressed by murine cumulus cells and participates in ovulation and in cumulus-oocyte complex (COC) expansion, maternal-fetal interaction and preterm labour. Despite these facts, the role of TLR4 in ovarian physiology is not fully understood. Therefore, the aim of the present study was to investigate the effects of TLR4 genetic ablation on mice folliculogenesis and female fertility, through analysis of reproductive crosses, ovarian responsiveness and follicular quantification in TLR4-/- (n = 94) and C57BL/6 mice [wild type (WT), n = 102]. TLR4-deficient pairs showed a reduced number of pups per litter (P = 0.037) compared with WT. TLR4-/- mice presented more primordial, primary, secondary and antral follicles (P < 0.001), however there was no difference in estrous cyclicity (P > 0.05). A lower (P = 0.006) number of COC was recovered from TLR4-/- mice oviducts after superovulation, and in heterozygous pairs, TLR4-/- females also showed a reduction in the pregnancy rate and in the number of fetuses per uterus (P = 0.007) when compared with WT. Altogether, these data suggest that TLR4 plays a role in the regulation of murine folliculogenesis and in determining ovarian endowment. TLR4 deficiency may affect ovulation and pregnancy rates, potentially decreasing fertility, therefore the potential side effects of its blockade have to be carefully investigated.

Meiosis Resumption of Immature Human Oocytes following Treatment with Calcium Ionophore In Vitro

Objective:

In vitro maturation (IVM) of human oocytes is used to induce meiosis progression in immature retrieved oocytes. Calcium (Ca2+) has a central role in oocyte physiology. Passage through meiosis phase to another phase is controlled by increasing intracellular Ca2+. Therefore, the current research was conducted to evaluate the role of calcium ionophore (CI) on human oocyte IVM.

Materials and Methods:

In this clinical trial study, immature human oocytes were obtained from 216 intracytoplasmic sperm injection (ICSI) cycles. After ovarian stimulation, germinal vesicle (GV) stage oocytes were collected and categorized into two groups: with and without 10 µM CI treatment. Next, oocyte nuclear maturation was assessed after 24–28 hours of culture. Real-time reverse transcription polymerase chain reaction (RT-PCR) was used to assess the transcript profile of several oocyte maturation-related genes (MAPK3, CCNB1, CDK1, and cyclin D1 [CCND1]) and apoptotic-related genes (BCL-2, BAX, and Caspase-3). Oocyte glutathione (GSH) and reactive oxygen species (ROS) levels were assessed using Cell Tracker Blue and 2’,7’-dichlorodihydrofluorescein diacetate (H2DCFDA) fluorescent dye staining. Oocyte spindle configuration and chromosome alignment were analysed by immunocytochemistry.

Results:

The metaphase II (MII) oocyte rate was higher in CI‐treated oocytes (73.53%) compared to the control (67.43%) group, but this difference was not statistically significant (P=0.13). The mRNA expression profile of oocyte maturation-related genes (MAPK3, CCNB1, CDK1, and CCND1) (P<0.05) and the anti-apoptotic BCL-2 gene was remarkably up-regulated after treatment with CI (P=0.001). The pro-apoptotic BAX and Caspase-3 relative expression levels did not change significantly. The CI‐treated oocyte cytoplasm had significantly higher GSH and lower ROS (P<0.05). There was no statistically significant difference in meiotic spindle assembly and chromosome alignment between CI treatment and the control group oocytes.

Conclusion:

The finding of the current study supports the role of CI in meiosis resumption of human oocytes. (Registration Number: IRCT20140707018381N4)

Role of intrauterine administration of transfected peripheral blood mononuclear cells by GM-CSF on embryo implantation and pregnancy rate in mice

One of the effective treatments in women with recurrent implantation failure (RIF) is the use of immune cells to facilitate embryo implantation. Previous studies have shown that intrauterine transmission of peripheral blood mononuclear cells (PBMC) increased the embryo implantation rate. In this study using B6D2F1 (C57BL/6 × DBA2) mice, a fragment of the granulocyte macrophage colony-stimulating factor (Gm-csf) gene was cloned into an enhanced green fluorescent protein vector (pEGFP-N1) and then transfected into PBMC. The protein level of GM-CSF was evaluated in the transfected PBMC and untransfected PBMC by ELISA. Attachment of mouse embryos and the mRNA expression levels of leukemia inhibitory factor (Lif), vascular endothelial growth factor (Vegf), matrix metalloproteinase 9 (Mmp9), Gmcsf-receptor (Gmcsf-r) and interleukin 6 (Il6) in vitro were assessed by real-time PCR in endometrial cells. To determine the pregnancy rate and number of implantation sites in vivo, the mouse uterine horns were analyzed on Day 7.5 post coitum. A greater amount of GM-CSF was produced in PBMC transfected with recombinant vector (552 pg/mL) compared with the untransfected PBMC (57 pg/mL) and PBMC transfected with empty vector (34 pg/mL) (P < 0.05). The data showed that the embryo attachment rate and mRNA expression levels (Vegf [1.7-fold], Mmp9 [1.4-fold], Lif [1.5-fold], Gm-csf r [1.6-fold] and Il6 [1.2-fold]) in the in vitro study (P < 0.01), pregnancy rate (P < 0.01) and number of implantation sites (P < 0.01) in the in vivo investigation (P < 0.05) were increased in PBMC transfected with recombinant vector compared with the PBMC group. The study demonstrated that, in mice, endometrium immunotherapy with transfected PBMC that contained recombinant GM-CSF before embryo implantation was effective in improving embryo implantation and endometrial receptivity.

Upregulation of interferon-alpha gene in bovine embryos produced in vitro in response to experimental infection with noncytophatic bovine-viral-diarrhea virus

In-vitro fertilization is a routine livestock-breeding technique widely used around the world. Several studies have reported the interaction of bovine viral-diarrhea virus (BVDV) with gametes and in-vitro-produced (IVP) bovine embryos. Since, gene expression in BVDV-infected IVP bovine embryos is scarcely addressed. The aim of this work was to evaluate the differential expression of genes involved in immune and inflammatory response. Groups of 20-25 embryos on Day 6 (morula stage) were exposed (infected) or not (control) to an NCP-BVDV strain in SOF medium. After 24 h, embryos that reached expanded blastocyst stage were washed. Total RNA of each embryo group was extracted to determine the transcription levels of 9 specific transcripts related with antiviral and inflammatory response by SYBR Green real time quantitative (RT-qPCR). Culture media and an aliquot of the last embryos wash on Day 7 were analyzed by titration and virus isolation, respectively. A conventional PCR confirmed BVDV presence in IVP embryos. A significantly higher expression of interferon-α was observed in blastocysts exposed to NCP-BVDV compared to the controls (p < 0.05). In this study, the upregulation of INFα and TLR7 genes involved in inflammatory and immune response in BVDV-infected IVP bovine embryos is a new finding in this field. This differential expression suggest that embryonic cells could function in a manner like immune cells by recognizing and responding early to interaction with viral pathogens. These results provide new insights into the action of BVDV on the complex molecular pathways controlling bovine early embryonic development.

The Effect of Increased miR-16-1 Levels in Mouse Embryos on Epigenetic Modification, Target Gene Expression, and Developmental Processes

Changes in microRNA (miRNA) levels are present in numerous diseases. Although these changes are particularly noted in male infertility, little is known about the effects of increased miR-16-1 in sperm from infertile men. In this study, we assessed the effects of increased mir-16-1 expression on the developmental process, epigenetic changes, and target gene expressions. IVF embryos, 6 h after insemination, were divided into three groups: control, control negative (CN), and miR-16-1 harboring plasmid microinjection. The developmental rates of these embryos were recorded after 24, 48, 72, and 96 h of culture. The levels of histone H3 lysine 4 tri-methylation (H3K4me3) and histone H3 lysine 27 tri-methylation (H3K27me3) were assessed in the 2-cell and blastocyst stages by immunofluorescence staining. Expression profiles of the miR16-1, Bax, Bcl-2, Suz12, and Kmt2a genes were measured by quantitative real-time polymerase chain reaction (qRT-PCR). There was a significant decrease from the 8-cell stage to the blastocyst stage of embryo development in the miR-16-1 harboring plasmid microinjection group. We observed substantial reductions in the amounts of H3K4me3 and H3K27me3 in the 2-cell and the blastocyst stages in the miR-16-1 harboring plasmid microinjection group (P ≤ 0.05). The miR-16-1 level in the miRNA group was higher than the control group in the 2-cell and the blastocyst stages. There was a significant increase (P ≤ 0.05) in Bax and decreases in Bcl2, Suz12, and Kmt2a following the injection of the miR-16-1 harboring plasmid. These results suggest that a change in miR-16-1 expression can significantly affect embryo development, epigenetic changes, and target gene expressions.

Upregulation of Toll-like receptor 4 through anti-miR-Let-7a enhances blastocyst attachment to endometrial cells in mice

Despite encouraging advances in fertility technology, the success rate of an ongoing pregnancy is relatively low and predominantly associated with implantation failure. Inflammatory responses are beneficial in the fetomaternal interface and supposedly accelerate the chances for successful implantation. The current study aims to determine the effect of Toll-like receptor 4 (TLR4) overexpression in mouse blastocysts via Let-7a downregulation using intracytoplasmic sperm injection-sperm-mediated gene transfer on embryo attachment rate. The pLenti-III-GFP-miR-Off-Let-7a vector was transmitted to oocytes derived via in vitro maturation (IVM) and in vivo oocytes by using NaOH-treated spermatozoa. Let-7a and TLR4 expression levels were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR), immunocytochemistry, and western blot analysis in both oocytes and embryos. Blastocyst adhesion on the endometrial cells was monitored by microscopic analysis. qRT-PCR results showed that Let-7a expression decreased in the IVM (GV-MII) oocytes compared to the in vivo oocyte (MII) group (p < .05). TLR4 showed a higher expression in GV-MII oocytes at both the gene and protein levels (p < .05). Following anti-miR-Let-7a transmission, the TLR4 expression level was significantly upregulated in embryos compared with the control groups (p < .05). Attachment and migration of trophoblasts cells towards endometrial cells dramatically increased compared to the control group (p < .05). Based on our results, we concluded that Let-7a might mediate embryo attachment through regulation of TLR4 expression levels.

Differentiation Induction and Proliferation Inhibition by A Cell-Free Approach for Delivery of Exogenous miRNAs to Neuroblastoma Cells Using Mesenchymal Stem Cells

Objective

Neuroblastoma (NB) is one of the frequently observed malignant solid tumors of childhood and infancy, accounting for 15% of pediatric cancer deaths. Recently, the approach of differentiation therapy has shown considerable promise in effective treatment of NB patients. MiR-124 belongs to the nervous system-specific miRNAs that is increased during neuronal differentiation and may be one of the potential therapeutic targets for the treatment of NB. However, despite its well-established therapeutic potential, its efficient delivery to the targeted tumor cells is a challenging task. Mesenchymal stem cells (MSCs) are multipotent adult progenitor cells that have antitumor properties, and they can migrate to cancer cells and tumors. This study aimed to assess whether human adipose tissue-derived MSCs (hAD- MSCs) have the potential to deliver exogenous miRNAs to NB cells to induce differentiation and decrease proliferation of cancer cells.

Materials and Methods

In this experimental study, hAD-MSCs were isolated, cultured, and differentiated. The M17 human NB cell line were also cultured. A specific type of miRNAs, i.e., miR-124 was successfully delivered to M17 NB cells with the aid of hAD-MSCs using the direct or indirect (exosome-based) contacts.

Results

It was shown that indirect delivery of miR-124 considerably decreased the proliferation of NB cells and induced their differentiation.

Conclusion

The results suggest the use of delivered exogenous miRNAs by the derived exosomes from hAD-MSCs as a novel cell-free stem cell-based therapy for NB cancer.

Aberrant expression of miR-29a/29b and methylation level of mouse embryos after in vitro fertilization and vitrification at two-cell stage

Proper epigenetic modifications during preimplantation embryo development are important for a successful pregnancy. We aim to investigate the putative influence of in vitro fertilization (IVF) and vitrification on DNA methylation in mouse preimplantation embryos. The study groups consisted of blastocyst-derived vitrified two-cell embryos, nonvitrified embryos, and a control group of in vivo derived blastocysts. We assessed developmental competence, global DNA methylation, relative expression levels of miR-29a/29b, and their target genes, Dnmt3a/3b. Vitrified embryos had a lower developmental rate as compared with nonvitrified embryos. There was no significant decrease in blastocyst cell numbers among studied groups, whereas there was a steady decline in DNA methylation after IVF and vitrification. The levels of miR-29a/29b upregulated in the experimental groups as compared with the control group. IVF and vitrification caused Dnmt3a/3b downregulations in blastocysts. The results of this study have suggested that a relationship exists between IVF and embryo vitrification with methylation interruptions in the blastocysts.

Expression of miR-Let-7a, miR-15a, miR-16-1, and their target genes in fresh and vitrified embryos and its surrounding culture media for noninvasive embryo assessment

microRNAs (miRNAs) play a critical role in implantation and development of mouse embryos. In this study, we aim to evaluate the possibility of miRNAs as potential biomarkers in the blastocyst culture to assess embryo quality. We also intend to investigate whether improved clinical outcomes of vitrified embryos agree with altered miRNA expressions. Mouse embryos from in vitro fertilization were vitrified at the two-cell stage. After thawing, the embryos were individually cultured and developed to the blastocyst stage. We used quantitative real-time polymerase chain reaction to evaluate miRNA expression levels in both vitrified and fresh groups, and culture medium (CM). The fibronectin binding assay was performed to examine for blastocyst attachment. The findings showed reduced expressions of miR-16-1 (0.2 ± 0.06) and miR-Let-7a (0.65 ± 0.1) after vitrification compared to fresh embryos. We observed significant upregulation of the target genes Vav3 (4.33 ± 0.25), integrin β-3 (Itg β3; 4.73 ± 0.2), and Bcl2 (2.29 ± 0.16) in the vitrified embryos compared to the fresh groups. Evaluation of blastocyst CM showed upregulation of miR-Let-7a (15.68 ± 0.89), miR-16-1 (16.18 ± 0.75), and miR-15a (13.36 ± 0.73) in the vitrified group in comparison to the fresh blastocysts (P < .05). The expression levels of miR-16-1 (3.28 ± 0.63), miR-15a (5.91 ± 0.38), and miR-Let-7a (9.07 ± 0.6) in CM of the vitrified blastocysts conducted on fibronectin were significantly higher than the fresh group (P < .05).This study showed that vitrification of embryos changes implantation and proliferation biomarkers. In addition, upregulated miRNAs in CM could be potentially used for noninvasive early assessment of embryo quality.

Thymoquinone reduces intracytoplasmic oxidative stress and improves epigenetic modification in polycystic ovary syndrome mice oocytes, during in-vitro maturation

Although in-vitro maturation (IVM) of oocytes has been presented as an alternative treatment to traditional stimulated in-vitro fertilization, the culture condition can be improved by natural antioxidants. Thus, we investigated the protective effect of Thymoquinone (TQ) during IVM in the polycystic ovary syndrome (PCOS) mice model. The induction of PCOS was made by dehydroepiandrosterone via subcutaneous injection, in prepubertal female B6D2F1-mice. After 21 days later, germinal vesicle (GV)-stage-oocytes were extracted and incubated in IVM media containing 0, 1.0, 10.0, and 100.0 μM of TQ. To assess fertilization and blastulation rates, after 22-24 hr, the treated oocytes were fertilized in-vitro with epididymal spermatozoa. Some other oocytes were evaluated for maturation, epigenetic, and oxidative stress markers. Similarly, the mRNA expression of epigenetic enzymes genes (Dnmt1 and Hdac1), three maternally derived genes (Mapk, CyclinB, and Cdk1) and apoptosis-related genes (Bax and Bcl2) were assessed. Our results showed that the maturation, fertilization, and blastulation rates were significantly higher in the 10.0 μM TQ-treated group compared with the untreated group and likewise with in-vivo matured oocytes. The Bax expression was reduced in 10.0 μM TQ matured oocytes, but Bcl2, Dnmt1, Hdac1, Cdk1, and Mapk were upregulated in this group compared to other groups. Furthermore, dimethylation of histone-3 at lysine-9 (H3K9m2) and DNA methylation were significantly increased whereas H4K12 acetylation (H4K12ac) was decreased in the 10.0 μM TQ-treated group in comparison with control and in-vivo matured oocytes. Therefore, our results are suggesting that 10.0 μM TQ may enhance the developmental competence of PCOS oocytes via the modulation of oxidative stress and epigenetic alterations.

DNA integrity and methylation changes of mouse spermatozoa following prolonged incubation

Sperm quality can be affected by different factors including the length of incubation time between sperm preparation and intracytoplasmic sperm injection. Here, we have evaluated the level of DNA methylation and expressions of related genes in mice spermatozoa. The spermatozoa were divided into three groups: fresh, spermatozoa incubated at room temperature (RT) and 37°C for 24 hr. The sperm chromatin structure assay was used to determine the DNA fragmentation index (DFI), and DNA methylation was analysed by flow cytometry. The expression levels of DNA methylation-related genes were determined by quantitative real-time PCR (qRT-PCR). According to the results, we observed significantly higher sperm progressive motility and viability in the group incubated at RT compared to the spermatozoa incubated at 37°C (p < 0.05). Spermatozoa incubated at 37°C had a higher DFI compared to the other groups (p < 0.05), but the DNA methylation level significantly decreased (p < 0.05). qRT-PCR analysis showed increased Dnmt-1 expression in spermatozoa after 24-hr incubation at 37°C. However, there were significantly higher expression levels of Dnmt-3l, Dnmt-3a and Dnmt-3b after incubation at both RT and 37°C compared to the fresh group (p < 0.05). The 24-hr incubation period affected both sperm DNA methylation and integrity. This study indicated that incubation at RT resulted in better sperm quality.

Does blastomere removal alter the expression level of miR-Let7a and its target genes following mouse embryo biopsy?

Embryo manipulations may cause the misexpression of various genes, most of which play critical roles in the regulation of implantation. This study aimed to evaluate the effects of embryo biopsy on the expression of miR-Let-7a and its gene targets including ErbB4, Tgf-α, Itg-αv, Itg β3 on the implantation of mouse embryo. Embryos were produced by in vitro fertilization followed by blastomere biopsy at the eight-cell stage. The effects of blastomere removal on the expression of genes ErbB4, Tgf-α, Itg αv, Itg β3, and miR-Let-7a as well as the alteration of the blastocyst cell number were compared in both biopsied and non-biopsied groups. Finally, blastocyst attachment was assessed on culture dishes precoated with Fibronectin. The results revealed that there were no significant differences between the biopsied and non-biopsied embryos with reference to the blastocyst formation rates, the average inner cell mass, trophectoderm cell number, and percentage of attachment of blastocysts (P > 0.05). The expression of ErbB4, Itg-β3, Itg-αv, TGF-α transcripts, and miR-Let-7a in blastocysts biopsied embryos did not differ from the non-biopsied blastocysts (P > 0.05). The results demonstrated that the preimplantation embryo development and attachment of biopsied embryos in vitro is not adversely affected by one blastomere biopsy at the eight-cell stage embryo.

Dimethyl sulphoxide and electrolyte-free medium improve exogenous DNA uptake in mouse sperm and subsequently gene expression in the embryo

SummaryOne of the methods to generate transgenic animals is called sperm-mediated gene transfer (SMGT). Mature sperm cells can take up exogenous DNA molecules intrinsically and transfer them into the oocyte during fertilization. This study assessed the effect of dimethyl sulfoxide (DMSO) and electrolyte-free medium (EFM) on DNA uptake (EGFP-N1plasmid) in mouse sperm. Sperms cells cultured in human tubular fluid (HTF) without any treatment were considered as the control group. Sperms cells that were incubated in EFM and HTF with DNA/DMSO at 4°C were classified into EFM and HTF groups. Sperm motility and viability were assessed following treatment. In vitro fertilization (IVF) with sperm in all groups was performed. Fertilization, embryo development and GFP-positive blastocyst rates were analyzed and compared. The result showed that sperm motility and viability in EFM were better than those in the HTF group. The rate of development to reach the blastocyst stage and GFP-positive blastocysts was significantly higher in the EFM group compared with the HTF group (P<0.05). Our data demonstrate that sperm stored in the EFM group can improve the efficiency of SMGT for the generation of GFP-positive blastocysts.

Improvement of oocyte in vitro maturation from mice with polycystic ovary syndrome by human mesenchymal stromal cell-conditioned media

The outcome of in vitro maturation (IVM) in the patients with polycystic ovary syndrome (PCOS) is poor. Abnormal intraovarian paracrine interplay alters microenvironment for oocyte development through folliculogenesis and decreases developmental competence of oocytes in patients with PCOS. Mesenchymal stromal cells (MSCs) secrete a variety of cytokines and growth factors that could promote oocyte maturation in vitro. Thus, in the current study we aimed to evaluate the effect of human bone marrow MSC-conditioned media (hBM-MSC-CM), as a supplement, to enrich IVM medium for PCOS germinal vesicles (GVs). For this purpose, oocytes at GV and metaphase II (MII) stages were harvested from PCOS mice. The GVs were randomly divided into four groups and incubated for 24 hours in an IVM medium (TCM199, as the control group) or TCM199 supplemented by 25%, 50%, and 75% of hBM-MSC-CM (PCOS-CM25, PCOS-CM50, and PCOS-CM75 groups, respectively) so as to evaluate which dose(s) could enhance maturation rate of the GVs and their subsequent in vitro fertilization (IVF) outcome. Furthermore, MII oocytes and their subsequent IVF outcome were considered as the in vivo matured (PCOS-IVO) group. The data showed that supplementation of IVM medium with 50% hBM-MSC-CM significantly increased cytoplasmic and nuclear maturation of the GVs (P < 0.001), and also fertilization and two-cell rate (P < 0.001) and blastocyst formation (P < 0.01) of in vitro matured oocytes from mice with PCOS. Overall, higher oocyte maturation and fertilization outcome in PCOS-CM50 group proposed that enrichment of IVM medium with hBM-MSC-CM could be considered as a promising approach to improve IVM of PCOS oocytes.