Polycystic ovary syndrome (PCOS) is the leading cause of anovulatory infertility and the most common endocrinopathy of women of reproductive age. Genome-wide association studies (GWAS) identified a number of loci associated PCOS in different ethnic populations, including women with Asian and European ancestry. Replication studies have confirmed some of these associations. Among the loci identified are those located near the LH receptor gene (LHCGR), a clathrin-binding protein gene (DENND1A) that also functions as a guanine nucleotide exchange factor, and the gene encoding RAB5B, a GTPase and protein involved in vesicular trafficking. The functional significance of one of these GWAS candidates (DENND1A) was supported by our discovery that a truncated protein splice variant of DENND1A termed DENND1A.V2, is elevated in PCOS theca cells, and that forced expression of DENND1A.V2 in normal theca cells increased CYP11A1 and CYP17A1 expression and androgen synthesis, a hallmark of PCOS. We previously proposed that the PCOS GWAS loci could be assembled into a functional network that contributes to altered gene expression in ovarian theca cells, resulting in increased androgen synthesis. Here we demonstrate the localization of LHCGR, DENND1AV.2 and RAB5B proteins in various cellular compartments in normal and PCOS theca cells. hCG and forskolin stimulation affects the distribution and co-localization of DENND1A.V2 and RAB5B in various cellular compartments This cytological evidence supports our PCOS gene network concept, and raises the intriguing possibility that LHCGR activation, via a cAMP-mediated process, promotes the translocation of DENND1A.V2 and RAB5B-containing vesicles from the PCOS theca cell cytoplasm into the nucleus, resulting in increased transcription of genes involved in androgen synthesis.

O objetivo deste estudo foi analisar as concentrações do fator de crescimento semelhante à insulina tipo 1 (IGF1) e insulina (INS) no fluido folicular durante foliculogênese em éguas, e localizar o receptor tipo 1 de IGF (IGF1R) nas paredes foliculares. Durante a estação reprodutiva, 40 éguas mestiças enviadas para abate em matadouro, com idades variando entre 6 e 16 anos foram utilizadas. As éguas foram abatidas de forma humanitária. Os tratos reprodutivos internos foram recuperados dentro de 10 min após o abate, ovários de éguas cíclicas foram separados do resto do aparelho. As éguas foram classificadas em quatro grupos: G1 – Folículo ≤ 13,5 mm e CL identificável; G2 – Folículo de 13,6 - 22,5 mm e CL identificável; G3 – Folículo de 22,6 - 31,5 mm e CL identificável; G4 – Folículo ≥ 31,6 mm e CL difícil de identificar. O fluido folicular (FF) foi aspirado e armazenado a -80 ° C até a sua utilização. Após a punção do FF, um fragmento da porção ventral da parede folicular foi removido para realizar a imunohistoquímica para localização de receptores IGF1R. O IGF1 livre foi determinado por ensaio imunoradiométrico. A INS foi determinada por um radioimunoensaio de fase líquida. A concentração de IGF1 livre e INS no FF aumentou com o crescimento folicular (P < 0,05). O escore imunohistoquímico de IGF1R nas células da granulosa e da teca interna da parede folicular equina em diferentes grupos aumentou (P < 0,05) com aumento folicular. Concluímos que as concentrações de IGF1 livre e INS no FF e de IGF1R em paredes foliculares de éguas aumentam com o crescimento folicular durante a foliculogênese, dando evidência do papel importante do IGF1 e INS no desenvolvimento folicular, e uma interação entre ambos hormônios na fisiologia reprodutiva ovariana. Sendo a égua um modelo de pesquisa para estudos comparativos na dinâmica folicular para consideração em mulheres, a conclusão deste estudo pode ser aplicada, também, a humanos. / The aim of this study was to analyze free type 1 insulin-like growth factor (IGF1) and insulin (INS) concentrations in follicular fluid during folliculogenesis in mares, and to localize type 1 IGF receptor (IGF1R) on follicular walls. During the breeding season, 40 mixed-breed mares sent to slaughter at an abattoir, with ages ranging between 6 to 16 years were used. Mares were humanely slaughtered. Internal reproductive tracts were recovered within 10 min after slaughter; ovaries of cyclic mares were separated from the rest of the tract. Mares were categorized into four groups: G1 – Follicle ≤ 13.5 mm and CL identifiable; G2 – Follicle of 13.6 to 22.5 mm and CL identifiable; G3 – Follicle of 22.6 to 31.5 mm and CL identifiable; G4 – Follicle ≥ 31.6 mm and CL difficult to identify. The follicular fluid (FF) was aspirated and stored at -80°C until use. After puncture of the FF, a fragment of the ventral portion of the follicular wall was removed to perform immunohistochemistry to localize IGF1R receptors. Free IGF1 was determined by immunoradiometric assay. INS was determined by a liquid phase radioimmunoassay. The concentration of free IGF1 and INS in FF increased with follicle growth (P < 0.05). Immunohistochemical score of IGF1R on granulosa and internal theca cells from equine follicular wall on different groups increase (P < 0.05) with follicular raise. We conclude that free IGF1 and INS concentrations in FF and IGF1R in follicular walls of mares increase with follicular growth during folliculogenesis, giving evidence of important role of IGF1 and INS in follicular development, and an interaction between both hormones in ovarian reproductive physiology. As the mare is a model research for comparative studies in follicular dynamics for consideration in women, the conclusion of this study can be applied to humans also.

Pig follicle development is a complex but poorly understood process involving both gonadotrophins and local ovarian factors. A series of studies sought to investigate these intrafollicular cell-to-cell interactions. Microarray analysis combined with gene ontology revealed that the oocyte, granulosa and theca cells each expressed more than 650 potential secreted factors and receptors, including members of the TGF-β, IGF1, EGF and FGF families. Using a well-defined in vivo experimental paradigm that generates follicles and oocytes of different quality, the temporal expression of several growth factors in the oocyte, granulosa and theca cells collected from sows during the recruitment and mid-selection phases, as well as the final selection of the preovulatory follicle population before and after the LH surge was studied. IGF1 expression patterns indicated its potential for modulating granulosa and theca cell function during the selection stages, and an involvement in creating differences in follicular quality between the first and second preovulatory wave post-weaning. Transient up-regulation of AREG and EREG mRNA around the LH surge, suggested their involvement in ovulation. Results of a second study investigating TGF-β superfamily expression, suggested a role for GDF9 in follicle selection through the up-regulation of TGFBR1 expression, while BMP15 could be involved in ovulation through the up-regulation of BMPR1B. Expression of angiogenesis-related genes during follicle development was also investigated. During mid-selection, ANGPT2 may allow VEGFA and similar factors to stimulate vascular development or destabilize the vasculature and cause follicular atresia, while ANGPT1 may be required in the preovulatory follicle population. Associations among the transcription factor HIF1A, VEGFA and ANGPT1, suggested interactions between the ligands in regulation of angiogenesis. Finally, the effects of the pig oocyte on cumulus cell function was assessed by co-culturing cumulus cell complexes with or without denuded oocytes isolated from large oestrogenic follicles. Presence of oocytes decreased FSHR and increased HSD3B expression, potentially stimulating progesterone while attenuating oestradiol production. In conclusion, oocytes were shown to control cumulus cell function in a way that reflects their specific environment and further evidence was obtained for a complex network of growth factors and receptors in the follicle and their involvement in regulation of pig follicle development. / Animal Science

No description available.

O objetivo deste estudo foi analisar as concentrações do fator de crescimento semelhante à insulina tipo 1 (IGF1) e insulina (INS) no fluido folicular durante foliculogênese em éguas, e localizar o receptor tipo 1 de IGF (IGF1R) nas paredes foliculares. Durante a estação reprodutiva, 40 éguas mestiças enviadas para abate em matadouro, com idades variando entre 6 e 16 anos foram utilizadas. As éguas foram abatidas de forma humanitária. Os tratos reprodutivos internos foram recuperados dentro de 10 min após o abate, ovários de éguas cíclicas foram separados do resto do aparelho. As éguas foram classificadas em quatro grupos: G1 – Folículo ≤ 13,5 mm e CL identificável; G2 – Folículo de 13,6 - 22,5 mm e CL identificável; G3 – Folículo de 22,6 - 31,5 mm e CL identificável; G4 – Folículo ≥ 31,6 mm e CL difícil de identificar. O fluido folicular (FF) foi aspirado e armazenado a -80 ° C até a sua utilização. Após a punção do FF, um fragmento da porção ventral da parede folicular foi removido para realizar a imunohistoquímica para localização de receptores IGF1R. O IGF1 livre foi determinado por ensaio imunoradiométrico. A INS foi determinada por um radioimunoensaio de fase líquida. A concentração de IGF1 livre e INS no FF aumentou com o crescimento folicular (P < 0,05). O escore imunohistoquímico de IGF1R nas células da granulosa e da teca interna da parede folicular equina em diferentes grupos aumentou (P < 0,05) com aumento folicular. Concluímos que as concentrações de IGF1 livre e INS no FF e de IGF1R em paredes foliculares de éguas aumentam com o crescimento folicular durante a foliculogênese, dando evidência do papel importante do IGF1 e INS no desenvolvimento folicular, e uma interação entre ambos hormônios na fisiologia reprodutiva ovariana. Sendo a égua um modelo de pesquisa para estudos comparativos na dinâmica folicular para consideração em mulheres, a conclusão deste estudo pode ser aplicada, também, a humanos. / The aim of this study was to analyze free type 1 insulin-like growth factor (IGF1) and insulin (INS) concentrations in follicular fluid during folliculogenesis in mares, and to localize type 1 IGF receptor (IGF1R) on follicular walls. During the breeding season, 40 mixed-breed mares sent to slaughter at an abattoir, with ages ranging between 6 to 16 years were used. Mares were humanely slaughtered. Internal reproductive tracts were recovered within 10 min after slaughter; ovaries of cyclic mares were separated from the rest of the tract. Mares were categorized into four groups: G1 – Follicle ≤ 13.5 mm and CL identifiable; G2 – Follicle of 13.6 to 22.5 mm and CL identifiable; G3 – Follicle of 22.6 to 31.5 mm and CL identifiable; G4 – Follicle ≥ 31.6 mm and CL difficult to identify. The follicular fluid (FF) was aspirated and stored at -80°C until use. After puncture of the FF, a fragment of the ventral portion of the follicular wall was removed to perform immunohistochemistry to localize IGF1R receptors. Free IGF1 was determined by immunoradiometric assay. INS was determined by a liquid phase radioimmunoassay. The concentration of free IGF1 and INS in FF increased with follicle growth (P < 0.05). Immunohistochemical score of IGF1R on granulosa and internal theca cells from equine follicular wall on different groups increase (P < 0.05) with follicular raise. We conclude that free IGF1 and INS concentrations in FF and IGF1R in follicular walls of mares increase with follicular growth during folliculogenesis, giving evidence of important role of IGF1 and INS in follicular development, and an interaction between both hormones in ovarian reproductive physiology. As the mare is a model research for comparative studies in follicular dynamics for consideration in women, the conclusion of this study can be applied to humans also.

O objetivo deste estudo foi analisar as concentrações do fator de crescimento semelhante à insulina tipo 1 (IGF1) e insulina (INS) no fluido folicular durante foliculogênese em éguas, e localizar o receptor tipo 1 de IGF (IGF1R) nas paredes foliculares. Durante a estação reprodutiva, 40 éguas mestiças enviadas para abate em matadouro, com idades variando entre 6 e 16 anos foram utilizadas. As éguas foram abatidas de forma humanitária. Os tratos reprodutivos internos foram recuperados dentro de 10 min após o abate, ovários de éguas cíclicas foram separados do resto do aparelho. As éguas foram classificadas em quatro grupos: G1 – Folículo ≤ 13,5 mm e CL identificável; G2 – Folículo de 13,6 - 22,5 mm e CL identificável; G3 – Folículo de 22,6 - 31,5 mm e CL identificável; G4 – Folículo ≥ 31,6 mm e CL difícil de identificar. O fluido folicular (FF) foi aspirado e armazenado a -80 ° C até a sua utilização. Após a punção do FF, um fragmento da porção ventral da parede folicular foi removido para realizar a imunohistoquímica para localização de receptores IGF1R. O IGF1 livre foi determinado por ensaio imunoradiométrico. A INS foi determinada por um radioimunoensaio de fase líquida. A concentração de IGF1 livre e INS no FF aumentou com o crescimento folicular (P < 0,05). O escore imunohistoquímico de IGF1R nas células da granulosa e da teca interna da parede folicular equina em diferentes grupos aumentou (P < 0,05) com aumento folicular. Concluímos que as concentrações de IGF1 livre e INS no FF e de IGF1R em paredes foliculares de éguas aumentam com o crescimento folicular durante a foliculogênese, dando evidência do papel importante do IGF1 e INS no desenvolvimento folicular, e uma interação entre ambos hormônios na fisiologia reprodutiva ovariana. Sendo a égua um modelo de pesquisa para estudos comparativos na dinâmica folicular para consideração em mulheres, a conclusão deste estudo pode ser aplicada, também, a humanos. / The aim of this study was to analyze free type 1 insulin-like growth factor (IGF1) and insulin (INS) concentrations in follicular fluid during folliculogenesis in mares, and to localize type 1 IGF receptor (IGF1R) on follicular walls. During the breeding season, 40 mixed-breed mares sent to slaughter at an abattoir, with ages ranging between 6 to 16 years were used. Mares were humanely slaughtered. Internal reproductive tracts were recovered within 10 min after slaughter; ovaries of cyclic mares were separated from the rest of the tract. Mares were categorized into four groups: G1 – Follicle ≤ 13.5 mm and CL identifiable; G2 – Follicle of 13.6 to 22.5 mm and CL identifiable; G3 – Follicle of 22.6 to 31.5 mm and CL identifiable; G4 – Follicle ≥ 31.6 mm and CL difficult to identify. The follicular fluid (FF) was aspirated and stored at -80°C until use. After puncture of the FF, a fragment of the ventral portion of the follicular wall was removed to perform immunohistochemistry to localize IGF1R receptors. Free IGF1 was determined by immunoradiometric assay. INS was determined by a liquid phase radioimmunoassay. The concentration of free IGF1 and INS in FF increased with follicle growth (P < 0.05). Immunohistochemical score of IGF1R on granulosa and internal theca cells from equine follicular wall on different groups increase (P < 0.05) with follicular raise. We conclude that free IGF1 and INS concentrations in FF and IGF1R in follicular walls of mares increase with follicular growth during folliculogenesis, giving evidence of important role of IGF1 and INS in follicular development, and an interaction between both hormones in ovarian reproductive physiology. As the mare is a model research for comparative studies in follicular dynamics for consideration in women, the conclusion of this study can be applied to humans also.

L'ovulation est le processus de rupture du follicule ovarien qui conduit à la libération d'un ovocyte dans l'oviducte pour la fécondation. Le processus ovulatoire est initié par un pic de LH qui conduit à l'activation du récepteur EGF (EGFR) dans les cellules de la granulosa (CG) qui stimule par conséquent l'expression de plusieurs gènes pré-ovulatoires essentiels. Environ 15% de l'infertilité chez les vaches est due à la présence de kystes ovariens qui se développent normalement à partir de follicules pré-ovulatoires qui n'ovulent pas. Chez les femmes et les rongeurs, alors que l'activité physiologique des effecteurs de signalisation Hippo semble essentielle pour la signalisation de l'EGF dans les CG, leur dérégulation peut jouer un rôle important dans les troubles kystiques anovulatoires. À notre connaissance, aucune étude n'a rapporté les rôles physiologiques ou physiopathologiques des effecteurs de la voie Hippo liés à l'ovulation ou à la formation de kystes ovariens chez les bovins. Les principaux objectifs de la présente thèse étaient donc (1) d'élucider l'importance de l'activité physiologique des effecteurs de signalisation Hippo dans la cascade pré-ovulatoire et dans l'ovulation chez les ruminants, et (2) de déterminer si la dérégulation de YAP dans le CG bovin est impliquée dans la pathogenèse de la maladie kystique des ovaires (MKO). Les résultats sont séparés en 2 articles. Dans le premier article, nous avons d'abord utilisé un système de culture de CG préovulatoire bien défini pour montrer que la signalisation YAP est essentielle pour l'expression de l'EGFR et des gènes cibles en aval EREG, EGR1 et TNFAIP6. Plus important encore, en utilisant un système d'injection folliculaire guidée par ultrasons, nous avons également montré que l'inhibiteur classique de la signalisation Hippo, la vertéporfine, inhibe l'ovulation induite par la GnRH in vivo chez les bovins. Dans le deuxième article, nous avons utilisé un modèle bovin de MKO spontanée pour montrer que l'abondance de l'ARNm et des protéines de YAP est significativement plus élevée dans les cellules de la granulosa et de la thèque (CT) isolées des follicules kystiques (structures folliculaires d'au moins 20 mm de diamètre) par rapport aux types de cellules respectifs isolés à partir de grands follicules non kystiques (≥12 mm). De plus, le schéma de phosphorylation de YAP et l'abondance accrue d'ARNm codant pour les gènes cibles YAP-TEAD classiques suggèrent que l'activité transcriptionnelle de YAP est augmentée dans les CG des kystes folliculaires par rapport aux grands follicules non kystiques. Ensemble, ces résultats montrent pour la première fois que la voie Hippo est essentielle à la cascade ovulatoire chez les bovins et que sa dérégulation peut jouer un rôle clé dans la pathogenèse de la maladie kystique des ovaires chez cette espèce. / Ovulation is the process of rupture of the ovarian follicle, which leads to the release of an oocyte into the oviduct for fertilization. The ovulatory process is initiated by a surge of LH that leads to the activation of the EGF receptor (EGFR) in granulosa cells (GC) which consequently stimulates the expression of several essential ovulatory genes. About 15% of infertility in cows is due to the presence of ovarian cysts that generally develop from pre-ovulatory follicles that fail to ovulate. In women and rodents, in addition to the essential physiological activity of Hippo signalling effectors for the EGF signalling in GC, their deregulation also plays an important role in anovulatory cystic disorders. To the best of our knowledge, no studies report physiological or pathophysiological roles of Hippo pathway effectors related to ovulation or ovarian cyst formation in cattle. The main objectives of the present thesis were, therefore, (1) to elucidate the importance of the physiological activity of Hippo signaling effectors in the pre-ovulatory cascade and in ovulation in ruminants and (2) to determine whether dysregulation of YAP in bovine GC is implicated in the pathogenesis of the cystic ovarian disease (COD). The results are separated into 2 articles. In the first article, we employed a well-defined preovulatory GC culture system to show that YAP signaling is essential for expressing EGFR and the downstream target genes EREG, EGR1 and TNFAIP6. Most importantly, using an ultrasound-guided follicular injection system, we have also shown that the classic Hippo signaling inhibitor verteporfin inhibits GnRH-induced ovulation in vivo in cattle. In the second article, we employed a bovine model of spontaneous COD to show that YAP mRNA and protein abundance are significantly higher in granulosa and theca (TC) cells isolated from cystic follicles (follicular structures of at least 20 mm in diameter) compared to the respective cell types isolated from large non-cystic follicles (≥12 mm). Moreover, the phosphorylation pattern of YAP and the increased abundance of mRNA encoding classical YAP-TEAD target genes suggest that the transcriptional activity of YAP is increased in GC of follicular cysts compared to large non-cystic follicles. Together, these results show for the first time that the Hippo pathway is critical to the ovulatory cascade in cattle and its dysregulation may play a key role in the pathogenesis of cystic ovarian disease in this species.

La mycotoxine déoxynivalénol (DON) et son métabolite déépoxy-déoxynivalenol (DOM-1) ont des effets significatifs sur la modification de la fonction des cellules thècales de l’ovaire bovin. L'objectif de cette étude était d'identifier les différentes voies de signalisation impliquées dans le mécanisme d'action de DON et DOM-1 par la spectrométrie de masse. Méthodes: Les cellules thécales de l'ovaire bovin ont été récoltées à partir des vaches adultes, indépendamment du stade du cycle œstral, et ont été cultivées à une densité de 500000 cellules viables dans 1 ml de milieu de McCoy pendant 5 jours. Les cellules ont ensuite été traitées au jour 5 de la culture avec 1 ng/ml de DON ou DOM-1 pendant 30 minutes et des échantillons cellulaires de protéins totales ont été préparés pour spectrométrie de masse. Résultats: la spectrométrie de masse a montré que DON et DOM-1 induisent une surexpression simultanée de ERK1/2, MAPK14 (p38alpha) et MAPK13 (p38delta). La spectrométrie de masse a également indiqué que 94 peptides ont été surexprimés tels que GNGT1, EDN1 et YWHAB. Ils régulent la plupart des voies de prolifération des cellules et sont impliqués dans la biosynthèse des lipides et des glucides. Néanmoins, 255 peptides ont été régulés à la baisse, tels que CALR3, PTGES3, RAD21, ACVR2B et TGFBR1 dont leurs activités sont principalement l'activation ou la désactivation des processus apoptotiques, et le métabolisme du glucose et de la choline. Nos résultats montrent que DON et DOM-1, à une dose de 1 ng/ml, ont le potentiel de stimuler la surexpression de MAPK distinctes et réguler négativement les voies de signalisation spécifiques qui stimulent la prolifération les cellules de la thèque de l’ovaire de bovin. / The mycotoxin deoxynivalenol (DON) and its metabolite deepoxy-DOM-1 have significant effects on bovine ovarian theca cell function. The objective of this study was to identify different signaling pathways involved in the mechanism of action of DON and DOM-1 by mass spectrometry. Methods: bovine ovarian theca cells were harvested from adult cows independently of the stage of the estrous cycle, and were cultured at a density of 500000 viable cells in 1 ml McCoy’s medium for 5 days. The cells were then treated on day 5 of culture with 1 ng/mL DON or DOM-1 for 30 minutes and total cell protein was collected for mass spectrometry. Results from mass spectrometry showed that both DON and DOM-1 induce simultaneous upregulation of ERK1/2 , MAPK14 (p38alpha) and MAPK13 (p38delta). Mass spectrometry also indicated that 94 peptides such as GNGT1, EDN1 and YWHAB were upregulated. They mostly regulate cell proliferation pathways and are involved in biosynthesis of lipid and carbohydrates. Nevertheless, 255 peptides such as CALR3, PTGES3, RAD21, ACVR2B and TGFBR1 were downregulated whose activities are mainly activation or deactivation of apoptotic processes, and glucose and choline metabolism. Our findings show that both DON and DOM-1 at least at a low dose (1 ng/ml) have the potential to stimulate upregulation of distinct MAPKs and downregulate specific signaling pathways that stimulate bovine ovarian theca cell proliferation.