RESUMO
Polycystic ovary syndrome (PCOS) is characterized by an oligo-anovulation, hyperandrogenism and polycystic ovarian morphology combined with major metabolic disturbances. However, despite the high prevalence and the human and economic consequences of this syndrome, its etiology remains unknown. In this study, we show that female Goto-Kakizaki (GK) rats, a type 2 diabetes mellitus model, encapsulate naturally all the reproductive and metabolic hallmarks of lean women with PCOS at puberty and in adulthood. The analysis of their gestation and of their fetuses demonstrates that this PCOS-like phenotype is developmentally programmed. GK rats also develop features of ovarian hyperstimulation syndrome. Lastly, a comparison between GK rats and a cohort of women with PCOS reveals a similar reproductive signature. Thus, this spontaneous rodent model of PCOS represents an original tool for the identification of the mechanisms involved in its pathogenesis and for the development of novel strategies for its treatment.
Assuntos
Síndrome do Ovário Policístico/patologia , Adiposidade , Animais , Animais Recém-Nascidos , Peso Corporal , Análise Discriminante , Modelos Animais de Doenças , Dislipidemias/patologia , Sistema Endócrino/patologia , Ciclo Estral , Feminino , Teste de Tolerância a Glucose , Gonadotropinas/farmacologia , Hormônios/sangue , Humanos , Secreção de Insulina , Análise dos Mínimos Quadrados , Lipídeos/química , Masculino , Troca Materno-Fetal , Análise Multivariada , Ovário/patologia , Ovário/fisiopatologia , Fenótipo , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia , Gravidez , Ratos Wistar , Reprodução , Maturidade SexualRESUMO
PURPOSE: A protective effect of anti-Müllerian hormone (AMH) on follicle atresia was recently demonstrated using long-term treatments, but this effect has never been supported by mechanistic studies. This work aimed to gain an insight into the mechanism of action of AMH on follicle atresia and on how this could account for the increased follicle pool observed in women with polycystic ovary syndrome (PCOS). METHODS: In vivo and in vitro experiments were performed to study the effects of AMH on follicle atresia and on the proliferation and apoptosis of granulosa cells (GCs). RNA-sequencing was carried out to identify new AMH target genes in GCs. The expression of some of these genes in GCs from control and PCOS women was compared using microfluidic real time quantitative RT-PCR. RESULTS: A short-term AMH treatment prevented follicle atresia in prepubertal mice. Consistent with this result, AMH inhibited apoptosis and promoted proliferation of different models of GCs. Moreover, integrative biology analyses of 965 AMH target genes identified in 1 of these GC models, confirmed that AMH had initiated a gene expression program favoring cell survival and proliferation. Finally, on 43 genes selected among the most up- and down-regulated AMH targets, 8 were up-regulated in GCs isolated from PCOS women, of which 5 are involved in cell survival. MAIN CONCLUSIONS: Our results provide for the first time cellular and molecular evidence that AMH protects follicles from atresia by controlling GC survival and suggest that AMH could participate in the increased follicle pool of PCOS patients.
