A spatial model showing differences between juxtacrine and paracrine mutual oocyte-granulosa cells interactions.

The bidirectional communication between oocytes and granulosa cells are mediated by several factors via a local feedback loop(s). The current model was carried out to study the spatial mutual interaction of porcine denuded oocytes and granulosa cells either in direct contact (juxtacrine) or paracrine co-culture using transwell system. Transwell 0.4 µm polyester membrane inserts were used to permit oocytes-granulosa cells paracrine communication with a distance of 2 mm between them in co-culture. Oocytes were cultured with granulosa cells in a defined basic maturation medium for 44 h. In results, oocyte secreted factors (OSFs; GDF9 and BMP15) temporal expression showed progressive decrement by the end of culture in case of direct contact with granulosa cells while it was increased progressively in the paracrine co-culture groups. However, oocytes that were cultured in direct contact showed a significant increase in blastocyst development after parthenogenetic activation than the paracrine co-cultured ones (20% vs. 11.5%, respectively). By the end of culture, granulosa cell count in direct contact showed a significant decrease than the indirect co-culture group (1.2 × 105 cell/mL vs. 2.1 × 105 cell/mL, respectively). Steroids (P4 and E2) and steriodogenesis enzymes mRNA levels showed significant temporal alterations either after 22 h and 44 h of IVM in both juxtacrine and paracrine co-culture systems (P ≤ 0.05). CX43 was much more highly expressed in the granulosa of the direct contact group than the indirect co-culture group. These results indicate the difference in mutual communication between oocytes and granulosa cells that were cocultured either in direct contact (juxtacrine) or with a short distance (paracrine) and propose a new paradigm to study different ovarian follicular cells interaction.

Effect of a high fat diet on ovary morphology, in vitro development, in vitro fertilisation rate and oocyte quality in mice

<p><b>INTRODUCTION</b>The aim of this study was to determine the effect of a high-fat diet (HFD) on oocyte maturation and quality in a mouse model.</p><p><b>METHODS</b>Female BALB/c mice were allocated to one of the following groups: (a) control group (n = 40), which received a controlled diet; or (b) HFD group (n = 40), which received an HFD for 12 weeks. Sections of the ovary were examined histologically. The number of follicles and corpora lutea were counted. In vitro maturation and in vitro fertilisation (IVF) were assessed in germinal vesicle (GV) and metaphase II (MII) oocytes, respectively. The expression of bone morphogenetic protein 15 (BMP15) and leptin receptor genes in GV and MII oocytes was evaluated using reverse transcription real-time polymerase chain reactions.</p><p><b>RESULTS</b>In the HFD group, there was a decreased number of primordial and Graafian follicles, as well as corpora lutea (p < 0.05). The rate of oocyte development to the MII stage was also reduced (p < 0.001). Cumulus expansion was observed more frequently in the control group than the HFD group (p < 0.05). The IVF rate in the HFD group was lower than that in the control group (p < 0.05). In the HFD group, BMP15 and leptin receptor genes were upregulated in the GV stage (p > 0.05) and MII stage (p < 0.05), compared to the control group.</p><p><b>CONCLUSION</b>An HFD reduces folliculogenesis in the primordial and Graafian stages, in vitro maturation and in vitro fertilisation rates, as well as oocyte quality in mice.</p>

Growth differentiation factor 9 and bone morphogenetic protein 15 expression in previtellogenic oocytes and during early embryonic development of Yellow-tail Kingfish Seriola lalandi

BACKGROUND: During fish oocyte maturation, specific molecules are expressed and accumulated within oocyte until fertilization and embryo development. Special attention have been paid in members of the transforming growth factor (TGF-ß) superfamily; growth differentiation factor 9 (GDF9/gdf9) and bone morphogenetic protein 15 (BMP15/bmp15), which exert regulatory functions during oocyte maturation and follicle development. However, little attention has been paid to the involvement of these molecules during embryogenesis considering its importance for the formation of a good quality egg and subsequent embryo survival. The purpose of this study was to analyze the expression of gdf9 andbmp15 in previtellogenic oocytes and during early embryonic development in Seriola lalandi, a pelagic fish with increasing prospect for its aquaculture development, which however, show high mortality at embryo and larval stages. RESULTS: Through RT-qPCR it was found that gdf9 expression was higher in previtellogenic oocytes decreasing after ovulation. This expression profile agrees with its participation in early stages of the follicular development. The transcripts for bmp15 also showed the highest levels in previtellogenic oocytes, however this expression was lower than obtained with gdf9. Conversely, in recently spawned oocytes mRNA bmp15 levels were highest than observed to gdf9. This, is consequent with the main role proposed for this growth factor at the final fish oocyte maturation: avoid the ovulation of an immature oocyte. During embryo development, low levels of mRNA were detected to gdf9, with an increase in 48 H post-fertilization embryos. The bmp15 expression did not change throughout development and was higher than gdf9 at 16 cells, blastula and appearance embryos stages. CONCLUSIONS: Both (gdf9 and bmp15) expression profiles in previtellogenic oocytes and newly spawned eggs are consistent with the described functions for these growth factors in vertebrate ovarian physiology in early and late stages of the follicular development. So, these genes could be considered as quality biomarkers at these stages. However, further studies of these proteins throughout folliculogenesis, are necessaries to fully understand their functions during the oocyte formation. In addition, the persistent expression of these growth factors during development, allows us to speculate possible roles in embryonic processes, which must also be addressed.

Effect of bushen tiaojing recipe on the quality of the oocytes and reproductive hormones in the follicular fluid in IVF-ET patients / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the effect of Bushen Tiaojing Recipe (BTR) on the quality of oocytes, reproductive hormones, and the expression of bone morphogenetic protein-15 (BMP15) of in vitro fertilization-embryo transfer (IVF-ET) patients.</p><p><b>METHODS</b>Sixty infertility patients who prepared for IVF-ET were assigned to two groups according to the treatment order, the treatment group [20 cases, treated with BTR + controlled ovarian hyperstimulation (COH)] and the control group (treated with COH alone, 40 cases). Age, the time limit for infertility, basal follicle-stimulating hormone (bFSH) concentration, usage days and the dosage of gonadotropins (Gn), serum levels of estradiol (E2), luteotropic hormone (LH), and progesterone (P) on the HCG injection day, the number of retrieved occytes, the fertilization rate, the number of embryos, the high quality embryo rate, and the clinical pregnancy rate were compared. Concentrations of follicle-stimulating hormone (FSH), LH, E2, testosterone (T), and P in the follicular fluid were detected via chemiluminescence microparticle immunoassay. The mRNA and protein expression of BMP-15 in mature granulosa cells was detected by real-time fluorescent PCR and Western blot.</p><p><b>RESULTS</b>Thirty-two patients were pregnant and the total pregnancy rate was 53.3%. Of them, 19 were pregnant and the total pregnancy rate was 47.5% in the control group, while 20 were pregnant and the total pregnancy rate was 65.0% in the treatment group. But there was no statistical difference between the two groups (P > 0.05). Compared with the control group, the Gn dosage was lower and the high quality embryo rate was higher in the treatment group, showing statistical difference (P < 0.05). There was no statistical difference in serum concentrations of E2, LH, or P on the HCG injection day, the number of retrieved oocytes, or the fertilization rate (P > 0.05). Compared with the control group, FSH concentrations in the follicular fluid were significantly lower and LH concentrations were significantly higher in the treatment group (P < 0.05). The LH concentrations in the follicular fluid were significantly higher in pregnant patients than non-pregnant patients, showing statistical difference (P < 0.05).There was no statistical difference in E2, T, or P concentrations (P > 0.05). The mRNA and protein expression of BMP-15 in granulosa cells was higher in the treatment group than in the control group (P < 0.05). It was also higher in pregnant patients than non-pregnant patients, showing statistical difference (P < 0.05).</p><p><b>CONCLUSION</b>During the IVF-ET process, BTR could elevate the quality of oocytes, and increase the sensitivity of ovarian follicles to exogenous Gn, which was correlated with the mRNA and protein expression of BMP-15 in granulosa cells, and changing concentrations of FSH and LH.</p>

Construction and specificity of porcine bmp15 gene reporter vector / 生物工程学报

The aim of this study is to identify the express specificity of bone morphogenetic protein 15 (Bmp15) in porcine. The pBMP15-EGFP reporter vector was constructed from the 2.2 kb fragment of porcine bmp15 promoter to trace the differentiation process of stem cells into oocyte-like cells. We used porcine ovary and Chinese Hamster Ovary cell line (CHO), mouse myoblast cell line (C2C12) and porcine amniotic fluid stem cell (pAFSC) to investigate the expression and regulation of this gene via RT-PCR, immunofluorescence, cell transfection, and microinjection methods. We also used single layer cell differentiation to detect the application potential of bmp15. The results show that bmp15 gene was specifically expressed in the porcine ovary and CHO rather than in C2C12 and pAFSC. In addition, the characteristic of tissue-specific of Bmp15 was detected on CHO instead of other cell lines by transient transfection. We also detected the expression of Bmp15 in oocyte at different development stages by immunofluorescence of fixed paraffin-embedded ovary sections. Furthermore, microinjection results show that bmp15 expressed in oocytes at 18 h of maturation in vitro, and continued up to 4-cell stage embryos. Most importantly, we found that the expression of Bmp15 started at day 12 after inducing pAFSC into oocyte-like cells by transfection; green fluorescent was visible in round cell masses. It indicated that bmp15 has the expression specificity and the pBMP15-EGFP reporter vector can be used to trace Bmp15 action in the differentiation of stem cells into germ cells.

Effects of phosphatidylinositol-3 kinase/protein kinase b/bone morphogenetic protein-15 pathway on the follicular development in the mammalian ovary / 中国医学科学院学报

In mammals, ovarian follicle is made of an oocyte with its surrounding granulosa cells and theca cells. Follicular growth and development is a highly coordinated programmable process, which guarantees the normal oocyte maturation and makes it having the fertilizing capacity. The paracrine and autocrine between oocytes and granulosa cells are essential for the follicular development to provide a suitable microenvironment. Phosphatidylinositol-3 kinase /protein kinase B is one of these important regulatory signaling pathways during this developmental process, and bone morphogenetic protein-15 an oocyte-specific secreted signal molecule, which regulates the follicular development by paracrine in the mammalian ovary. The present article overviewed the role of phosphatidylinositol-3 kinase / protein kinase B signaling during the follicular development based on our previous investigation about protein kinase B /forkhead transcription factor forkhead family of transcription factors -3a, and then focused on the regulatory effects of bone morphogenetic protein-15, as a downstream signal molecule of phosphatidylinositol-3 kinase / forkhead family of transcription factors -3a pathway, on ovarian follicular development, which helped to further understand the molecular mechanism regulating the follicular development and to treat ovarian diseases like infertility.

Women with poor response to ovarian stimulation have increased follicular bone morphogenetic protein-15 levels / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To evaluate the levels of bone morphogenetic protein-15 (BMP-15) in human follicular fluid (FF) and its association with response to ovarian stimulation.</p><p><b>METHODS</b>Western blotting was performed to determine the levels of BMP-15 in FF obtained from follicle aspirates in 70 patients undergoing IVF treatment. According to the response to ovarian stimulation the patients were divided into poor responder group and normal responder group.</p><p><b>RESULT</b>BMP-15 levels in FF of poor responders were significantly higher than those in normal responders (1.01 +/- 0.34 vs 0.77 +/- 0.24, P<0.01).</p><p><b>CONCLUSION</b>Increased levels of BMP-15 in FF may be associated with poor response to ovarian stimulation.</p>

Growth differentiation factor-9 gene expression in in vitro cultured oocytes in mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To explore the relation between oocyte maturation and growth differentiation factor-9 (GDF-9) gene expression.</p><p><b>METHODS</b>Ovariectomy was performed in 50 Kunming female mice of 10 days old, and the preantral follicles were isolated from the ovaries and cultured in medium drops for 12 days. Oocytes and somatic cells were mechanically isolated. The oocytes cultured in vitro for 2, 4, 6, 8, 10, and 12 days constituted the in vitro cultured group and the oocytes obtained from female mice of 12, 14, 16, 18, 20, and 22 days old served as the in vivo group. Semi-quantitative RT-PCR and agar gel electrophoresis were performed to quantify GDF-9 gene expression in each oocyte.</p><p><b>RESULTS</b>Follicle survival, antrum formation and maturation rate was 89.5%, 51.8% and 56.6% in the in vitro cultured follicles, respectively. GDF-9 gene expression on days 2, 4, 6, 8, 10, and 12 in in vitro cultured oocytes was 0.83-/+0.08, 0.52-/+0.09, 0.45-/+0.13, 0.49-/+0.09, 0.49-/+0.09, and 0.68-/+0.08, respectively; GDF-9 gene expression in in vivo grown oocytes of 12, 14, 16, 18, 20, and 22 days were 0.64-/+0.35, 0.48-/+0.10, 0.52-/+0.10, 0.66-/+0.08, 0.72-/+0.09, and 0.91-/+0.11, respectively. Between days 8 and 12, GDF-9 gene expression in in vitro cultured oocyte was significantly lower than that in in vivo grown oocytes (P<0.05).</p><p><b>CONCLUSION</b>MII oocytes can be obtained from in vitro culture of the preantral follicles. GDF-9 gene expression in the oocytes varies with their growth stages. Between days 8 and 12 of in vitro culture, GDF-9 gene expression in the cultured oocytes is different from that in in vivo grown oocytes.</p>

Mutational Analysis of Growth Differentiation Factor-9 Gene in Korean Women with Premature Ovarian Failure / 대한산부인과학회잡지

The clinical models for studying ovary-determining genes may be premature ovarian failure (POF). POF is a condition causing amenorrhea, hypoestrogenism, and elevated gonadotropins in women under 40 years old. FSH receptor, LH receptor, inhibin, GDF-9 (growth differentiation factor-9), BMP-15 (bone morphogenetic protein-15), DIAPH2 (diaphanous gene) and XPNPEP2 (X-prolyl aminopeptidase) genes were proposed as a possible candidate gene, but until recently, only mutations in FSH receptor, LH receptor and inhibin genes have been identified in POF patients. Therefore mutation screening of another POF gene necessary to reveal the principal causative genes of POF. OBJECTIVE: The present study was performed to analyze the mutation of GDF-9 gene in Korean patient with POF and to investigate whether mutation of these gene is a likely main cause of POF. METHODS: Eighty-six women with POF were studied and thirty-six normal women were enrolled as control. Mutation screening of these genes were performed by denaturing HPLC and were confirmed by automatic sequencing. RESULTS: Three different mutations of GDF-9 gene were identified in Korean women with POF; Arg3Cys mutation in one patient, Leu40Val mutation in one patient, Asp57Tyr mutation in 10 patients and 5 normal controls. Arg3Cys mutation and Leu40Val mutation were likely cause of disease. Frequencies of Arg3Cys mutation and Leu40Val mutation were 1.2%, respectively. Asp57Tyr mutation was common polymorphism in Korean women. All mutations was a novel mutation found in the present study. CONCLUSION: POF was resulted by mutations of GDF-9 gene, but mutations of GDF-9 gene are not likely main causes of POF because of low frequency of mutations.