Uncoupling between proliferation and differentiation of ovine granulosa cells in vitro

1994 ◽  
Vol 142 (3) ◽  
pp. 497-510 ◽  
Author(s):  
D Monniaux ◽  
C Pisselet ◽  
J Fontaine

Abstract Granulosa cells of ovarian follicles both proliferate and undergo differentiation. In vivo, an inverse relationship between proliferation and steroidogenesis is observed. However, both processes can be enhanced by insulin-like growth factor-I (IGF-I) in vitro. Studies were undertaken in the ewe to understand the mechanisms controlling the balance between proliferation and differentiation in cultured granulosa cells from antral follicles better. For this purpose, granulosa cells from ovine small follicles (1–3 mm in diameter) and large follicles (5–7 mm in diameter) were compared for progesterone secretion, cytochrome P450 side-chain cleavage (P450scc) expression and their proportions of non-proliferating (G0) cells, in response to IGF-I and FSH stimulation in vitro. IGF-I mainly enhanced the proliferation of granulosa cells from small follicles but it strongly increased progesterone secretion and P450scc expression in granulosa cells from large follicles, in synergy with FSH. Blocking granulosa cell proliferation by the administration of colcemid or aphidicolin had no effect or a weak stimulating effect on progesterone secretion. At the beginning of the culture period, the proportion of non-proliferating cells, estimated by continuous [3H]thymidine labelling experiments, was clearly higher in large than in small follicles (91% vs 30%, P<0·001). For both cell types, treatment with IGF-I in vitro reduced the proportion of non-proliferating cells at 72 h of culture (40% vs 70% respectively in IGF-I-stimulated and unstimulated cells from large follicles, P<0·001, and 17% vs 30% respectively in IGF-I-stimulated and unstimulated cells from small follicles, P<0·001). Treatment with FSH had no effect on the proportion of non-proliferating cells. As revealed by immunohistochemistry experiments, IGF-I, in synergy with FSH, clearly increased the percentage of cells expressing P450scc enzyme and the intensity of staining in granulosa cells from large follicles. Unexpectedly, heavily stained cells in mitosis were observed in IGF-I-stimulated cells from large follicles after 96 h of culture, suggesting that dividing cells might also produce progesterone. Overall, these results support the hypothesis that the growth-promoting and the cytodifferentiative effects of IGF-I are clearly distinct. Moreover, they suggest that uncoupling between proliferation and steroidogenesis may occur in cultured ovine granulosa cells. The loss of proliferative activity accompanying terminal follicular growth in vivo could be reversed in vitro. During terminal follicular growth in vivo, the existence of an active mechanism inhibiting granulosa cell proliferation, and unrelated to terminal differentiation, is therefore strongly suspected. Journal of Endocrinology (1994) 142, 497–510

2020 ◽  
Vol 27 (10) ◽  
pp. 2856-2871 ◽  
Author(s):  
Marie-Cécile De Cian ◽  
Elodie P. Gregoire ◽  
Morgane Le Rolle ◽  
Simon Lachambre ◽  
Magali Mondin ◽  
...  

Abstract R-spondin2 (RSPO2) is a member of the R-spondin family, which are secreted activators of the WNT/β-catenin (CTNNB1) signaling pathway. In the mouse postnatal ovary, WNT/CTNNB1 signaling is active in the oocyte and in the neighboring supporting cells, the granulosa cells. Although the role of Rspo2 has been previously studied using in vitro experiments, the results are conflicting and the in vivo ovarian function of Rspo2 remains unclear. In the present study, we found that RSPO2/Rspo2 expression is restricted to the oocyte of developing follicles in both human and mouse ovaries from the beginning of the follicular growth. In mice, genetic deletion of Rspo2 does not impair oocyte growth, but instead prevents cell cycle progression of neighboring granulosa cells, thus resulting in an arrest of follicular growth. We further show this cell cycle arrest to be independent of growth promoting GDF9 signaling, but rather associated with a downregulation of WNT/CTNNB1 signaling in granulosa cells. To confirm the contribution of WNT/CTNNB1 signaling in granulosa cell proliferation, we induced cell type specific deletion of Ctnnb1 postnatally. Strikingly, follicles lacking Ctnnb1 failed to develop beyond the primary stage. These results show that RSPO2 acts in a paracrine manner to sustain granulosa cell proliferation in early developing follicles. Taken together, our data demonstrate that the activation of WNT/CTNNB1 signaling by RSPO2 is essential for oocyte-granulosa cell interactions that drive maturation of the ovarian follicles and eventually female fertility.


2001 ◽  
Vol 170 (3) ◽  
pp. 565-573 ◽  
Author(s):  
F Khamsi ◽  
S Roberge

There are two types of granulosa cells: those which surround the oocyte are cumulus cells (CC) and those which surround the antrum are mural granulosa cells (MGC). These cells are under the influence of several hormones and growth factors, the most important of which are gonadotrophins and IGF-I. In this article, we report novel observations on the differences between these two types of granulosa cells and their interaction with gonadotrophins and IGF-I. We were able to conduct physiological studies on the role of IGF-I by using an analogue of IGF-I which does not bind to IGF-I-binding proteins (LR3-IGF-I). Immature rats received saline, equine chorionic gonadotrophin (eCG), LR3-IGF-I or eCG plus LR3-IGF-I by infusion using a pump from 24-29 days of age. The rats were killed and the ovaries removed. Surface follicles were punctured and MGC and oocyte cumulus complexes were removed. These were cultured in saline (control) and in three different doses of FSH. Cell replication was assessed by 3H-thymidine incorporation and differentiation was evaluated by the measurement of progesterone secretion. It was noted that CC replicated ten times more than MGC. Similarly, progesterone secretion by CC was six times more than by MGC. In vivo exposure to gonadotrophins (eCG) positively influenced in vitro treatment with FSH in both cell types. This phenomenon was observed in both cell replication and progesterone secretion. The IGF-I analogue had a positive effect on cell replication of MGC but a negative effect on the cell replication of CC. With respect to progesterone secretion, the IGF-I analogue had a negative effect on CC but a positive effect on MGC. In conclusion, CC behaved differently from MGC in response to gonadotrophins and the IGF-I analogue. IGF-I and FSH acted additively, synergistically or antagonistically in different circumstances.


2019 ◽  
Vol 101 (5) ◽  
pp. 986-1000 ◽  
Author(s):  
Hongyan Zhu ◽  
Ning Qin ◽  
Xiaoxing Xu ◽  
Xue Sun ◽  
Xiaoxia Chen ◽  
...  

Abstract SALL1 and SALL3 are transcription factors that play an essential role in regulating developmental processes and organogenesis in many species. However, the functional role of SALL1 and SALL3 in chicken prehierarchical follicle development is unknown. This study aimed to explore the potential role and mechanism of csal1 and csal3 in granulosa cell proliferation, differentiation, and follicle selection within the prehierarchical follicles of hen ovary. Our data demonstrated that the csal1 and csal3 transcriptions were highly expressed in granulosa cells of prehierarchical follicles, and their proteins were mainly localized in the cytoplasm of granulosa cells and oocytes as well as in the ovarian stroma and epithelium. It initially revealed that both csal1 and csal3 may be involved in chicken prehierarchical follicle development via a translocation mechanism. Furthermore, our results showed an abundance of CCND1, Bcat, StAR, CYP11A1, and FSHR mRNA in granulosa cells, and the proliferation levels of granulosa cells from the prehierarchical follicles were significantly increased by siRNA-mediated knockdown of csal1 or/and csal3. Conversely, the overexpression of csal1 or/and csal3 in the granulosa cells led to a remarkably decreased of them. Moreover, csal1 and csal3 together exert a much stronger effect on the regulation than any of csal1 or csal3. These results indicated that csal1 and csal3 play synergistic inhibitory roles on granulosa cell proliferation, differentiation, and steroidogenesis during prehierarchical follicle development in vitro. The current data provide a basis of molecular mechanisms of csal1 and csal3 in controlling the prehierarchical follicle development and growth of hen ovary in vivo.


Author(s):  
Tianyanxin Sun ◽  
Francisco J. Diaz

Abstract Background The Hippo pathway plays critical roles in regulating cell proliferation, differentiation and survival among species. Hippo pathway proteins are expressed in the ovary and are involved in ovarian function. Deletion of Lats1 causes germ cell loss, ovarian stromal tumors and reduced fertility. Ovarian fragmentation induces nuclear YAP1 accumulation and increased follicular development. At ovulation, follicular cells stop proliferating and terminally differentiate, but the mechanisms controlling this transition are not completely known. Here we explore the role of Hippo signaling in mouse granulosa cells before and during ovulation. Methods To assess the effect of oocytes on Hippo transcripts in cumulus cells, cumulus granulosa cells were cultured with oocytes and cumulus oocyte complexes (COCs) were cultured with a pSMAD2/3 inhibitor. Secondly, to evaluate the criticality of YAP1 on granulosa cell proliferation, mural granulosa cells were cultured with oocytes, YAP1-TEAD inhibitor verteporfin or both, followed by cell viability assay. Next, COCs were cultured with verteporfin to reveal its role during cumulus expansion. Media progesterone levels were measured using ELISA assay and Hippo transcripts and expansion signatures from COCs were assessed. Lastly, the effects of ovulatory signals (EGF in vitro and hCG in vivo) on Hippo protein levels and phosphorylation were examined. Throughout, transcripts were quantified by qRT-PCR and proteins were quantified by immunoblotting. Data were analyzed by student’s t-test or one-way ANOVA followed by Tukey’s post-hoc test or Dunnett’s post-hoc test. Results Our data show that before ovulation oocytes inhibit expression of Hippo transcripts and promote granulosa cell survival likely through YAP1. Moreover, the YAP1 inhibitor verteporfin, triggers premature differentiation as indicated by upregulation of expansion transcripts and increased progesterone production from COCs in vitro. In vivo, ovulatory signals cause an increase in abundance of Hippo transcripts and stimulate Hippo pathway activity as indicated by increased phosphorylation of the Hippo targets YAP1 and WWTR1 in the ovary. In vitro, EGF causes a transient increase in YAP1 phosphorylation followed by decreased YAP1 protein with only modest effects on WWTR1 in COCs. Conclusions Our results support a YAP1-mediated mechanism that controls cell survival and differentiation of granulosa cells during ovulation.


Reproduction ◽  
2010 ◽  
Vol 140 (2) ◽  
pp. 295-303 ◽  
Author(s):  
Jennifer L Juengel ◽  
Lisa J Haydon ◽  
Brigitta Mester ◽  
Brian P Thomson ◽  
Michael Beaumont ◽  
...  

IGFs are known to be key regulators of ovarian follicular growth in eutherian mammals, but little is known regarding their role in marsupials. To better understand the potential role of IGFs in the regulation of follicular growth in marsupials, expression of mRNAs encoding IGF1, IGF2, IGF1R, IGF-binding protein 2 (IGFBP2), IGFBP4 and IGFBP5 was localized by in situ hybridization in developing ovarian follicles of the brushtail possum. In addition, the effects of IGF1 and IGF2 on granulosa cell function were tested in vitro. Both granulosa and theca cells synthesize IGF mRNAs, with the theca expressing IGF1 mRNA and granulosa cell expressing IGF2 mRNA. Oocytes and granulosa cells express IGF1R. Granulosa and theca cells expressed IGFBP mRNAs, although the pattern of expression differed between the BPs. IGFBP5 mRNA was differentially expressed as the follicles developed with granulosa cells of antral follicles no longer expressing IGFBP5 mRNA, suggesting an increased IGF bioavailability in the antral follicle. The IGFBP protease, PAPPA mRNA, was also expressed in granulosa cells of growing follicles. Both IGF1 and IGF2 stimulated thymidine incorporation but had no effect on progesterone production. Thus, IGF may be an important regulator of ovarian follicular development in marsupials as has been shown in eutherian mammals.


2017 ◽  
Vol 234 (1) ◽  
pp. 1-14 ◽  
Author(s):  
Li Zhang ◽  
XiaoXin Zhang ◽  
Xuejing Zhang ◽  
Yu Lu ◽  
Lei Li ◽  
...  

MicroRNAs (MiRNAs) play important regulatory roles in many cellular processes. MiR-143 is highly enriched in the mouse ovary, but its roles and underlying mechanisms are not well understood. In the current study, we show that miR-143 is located in granulosa cells of primary, secondary and antral follicles. To explore the specific functions of miR-143, we transfected miR-143 inhibitor into primary cultured granulosa cells to study the loss of function of miR-143 and the results showed that miR-143 silencing significantly increased estradiol production and steroidogenesis-related gene expression. Moreover, our in vivo and in vitro studies showed that follicular stimulating hormone (FSH) significantly decreased miR-143 expression. This function of miR-143 is accomplished by its binding to the 3’-UTR of KRAS mRNA. Furthermore, our results demonstrated that miR-143 acts as a negative regulating molecule mediating the signaling pathway of FSH and affecting estradiol production by targeting KRAS. MiR-143 also negatively acts in regulating granulosa cells proliferation and cell cycle-related genes expression. These findings indicate that miR-143 plays vital roles in FSH-induced estradiol production and granulosa cell proliferation, providing a novel mechanism that involves miRNA in regulating granulosa cell functions.


1985 ◽  
Vol 110 (3) ◽  
pp. 401-407 ◽  
Author(s):  
T. Hillensjö ◽  
A. Sjögren ◽  
B. Strander ◽  
L. Nilsson ◽  
M. Wikland ◽  
...  

Abstract. Granulosa cells were obtained from human preovulatory follicles in 31 women undergoing in vitro fertilization and embryo transfer due to tubal infertility. Follicular maturation was stimulated and synchronized by treatment with Clomiphene or human menopausal gonadotrophin (hMG), or both, plus human chorionic gonadotrophin (hCG). Follicles were aspirated by ultrasound guided puncture approximately 34–36 h after the hCG injection. The granulosa cells were washed and suspended in modified medium 199 containing 10% foetal bovine serum and cultured as monolayers for 6–8 days in the absence and presence of hormones and reactants. Progesterone formation was analyzed by RIA. In general, the cells underwent morphological luteinization and secreted high amount of progesterone. Under basal conditions the secretion of progesterone was highest during the first 2 days in culture and then gradually declined. Progesterone secretion was stimulated by human LH, hCG and the adenylate cyclase stimulator forskolin, with a maximal effect between days 2–6. The β-adrenergic agonist isoproteronol in preliminary experiments potentiated the stimulatory effect of hCG but had no own stimulatory effect. No clear differences in progesterone secretion or responsiveness to in vitro stimulation relating to the various in vivo stimulation protocols were found.


2009 ◽  
Vol 202 (3) ◽  
pp. 347-353 ◽  
Author(s):  
M F Machado ◽  
V M Portela ◽  
C A Price ◽  
I B Costa ◽  
P Ripamonte ◽  
...  

Fibroblast growth factor 17 (FGF17) is a member of the FGF8 subfamily that appears to be relevant to folliculogenesis and oogenesis, as the prototype member FGF8 is an oocyte-derived protein that signals to cumulus cells. FGF8 has structural and receptor-binding similarities to FGF17, whose expression in the ovary has not been reported. In this study, we demonstrate localization of FGF17 protein to the oocyte of preantral follicles, and to the oocyte and granulosa cells of antral follicles. Real-time PCR demonstrated the presence of mRNA in oocytes and, to a lesser extent, in granulosa and theca cells. FGF17 mRNA abundance was low in granulosa and theca cells from healthy follicles and increased significantly in atretic follicles. Addition of FSH or IGF-I to granulosa cells in vitro decreased FGF17 mRNA abundance, and treatment with FGF17 inhibited estradiol and progesterone secretion from granulosa cells in relation to control cultures without these additives. We conclude that FGF17 is a potential mediator of granulosa cell differentiation.


1994 ◽  
Vol 140 (2) ◽  
pp. 313-319 ◽  
Author(s):  
P Ovesen ◽  
H J Ingerslev ◽  
H Ørskov ◽  
T Ledet

Abstract Numerous clinical and experimental observations have suggested that GH is important in ovarian function. We have investigated the effect of GH alone and GH in combination with FSH on the secretion of oestradiol, progesterone, insulin-like growth factor-I (IGF-I) and IGF-binding protein-1 (IGFBP-1) and on [3H]thymidine incorporation in cultured human luteinized granulosa cells. Granulosa cells from patients undergoing treatment for in vitro fertilization were isolated and cultured for 2 days in culture medium with 10% serum. After this preincubation, the medium was removed and the cells were incubated with GH (1, 10 and 100 μg/l) with or without FSH in serum-free medium and in the presence of [3H]methylthymidine (2 μCi/ml). GH alone resulted in a significant dose-dependent increase of oestradiol (P<0·05) and in IGFBP-1 (P<0·002) in the medium. The release of IGF-I was undetectable and there was no increase in [3H]thymidine incorporation with GH alone. Neither GH nor FSH alone stimulated granulosa cell proliferation or progesterone release, while the combination induced increases (P<0·001) in both. The stimulatory effect of GH on steroidogenesis, IGFBP-1 production and granulosa cell proliferation supports a putative role for GH in the regulation of ovarian function. Journal of Endocrinology (1994) 140, 313–319


Zygote ◽  
1996 ◽  
Vol 4 (04) ◽  
pp. 317-321 ◽  
Author(s):  
Barbara C. Vanderhyden

Investigations of strains of mice defective in germ cell development have revealed the importance of oocytes for the initial stages of folliculogenesis (Pellaset al., 1991; Huanget al., 1993). Various aspects of follicular development are dependent upon and/or influenced by the presence of oocytes, including granulosa cell proliferation (Vanderhydenet al., 1990, 1992) and cumulus expansion (Buccioneet al., 1990; Salustriet al., 1990; Vanderhydenet al., 1990; Vanderhyden, 1993). We are investigating the possibility that oocytes influence one of the primary functions of granulosa cells: steroidogenesis. In many species, granulosa cells removed from preovulatory follicles luteinisein vitro(Channinget al., 1982), presumably due to loss of contact with follicular luteinisation inhibitory factor(s). Indeed, follicular fluid can prevent granulosa cell luteinisationin vitro(Ledwitz-Rigbyet al., 1977). Follicular fluid, however, may simply be the medium for transport of factors secreted by oocytes to regulate granulosa cell activities.


Sign in / Sign up

Export Citation Format

Share Document