Reproduction Abstracts

Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility but typically is also associated with insulin resistance, disordered energy balance and a predisposition to develop type 2 diabetes mellitus. Anovulation is characterised by arrest of antral follicles but there is compelling evidence for disordered regulation of the early stages of preantral follicle development in the ovaries of women with PCOS. Dysregulation of local growth factor function a...

Polycystic ovary syndrome (PCOS) is a complex endocrine disorder that presents in women of reproductive age. The aetiology of PCOS is poorly understood, however it is likely that women with this disorder are predisposed to produce excess androgen at or well before puberty. Environmental and lifestyle factors then contribute to the multifarious symptoms observed. One such key external factor is diet. These studies utilised a prenatally exposed androgen mouse model to investigat...

Introduction: Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility affecting over 5% of the female population. PCOS is characterized by aberrant early follicle development in which hyperandrogenism is thought to play a key role. However, the molecular mechanisms of androgen action within the ovary remain largely unknown. Recent evidence suggests androgens may be acting, in part, through modulation of growth factor signalling. We have recently sh...

Introduction: Female mammals are born with a finite reserve of primordial follicles which dictates the reproductive lifespan. Despite this the factors responsible for primordial follicle activation remain largely unknown. The transforming growth factor beta (TGFβ) superfamily has been implicated in early follicle development however little attention has been given to the effects of TGFβ2, expression of which has been demonstrated in the ovary. This study aimed to exa...

Polycystic ovary syndrome (PCOS) is a common endocrinopathy that is associated with anovulatory infertility, menstrual disturbances as well as an adverse metabolic profile. Hyperandrogenism is the hallmark of PCOS and originates predominantly from ovarian theca cells. Obesity increases androgen synthesis, partly due to accompanying hyperinsulinemia but also as a result of an effect of adipokines on ovarian steroidogenesis (Comim et al. PLoS ONE 8</str...

The onset of mammalian follicle development is marked by granulosa cell (GC) proliferation, GC shape change, and oocyte growth. Despite their critical role in female fertility the factors and mechanisms underlying these cellular changes remain largely unknown. The transforming growth factor beta (TGFβ) superfamily has been strongly implicated in early follicle growth. Disruption of the function or expression of members of the TGFβ superfamily, receptors or key compon...

Hyperandrogenism and dysregulated follicle development both characterise polycystic ovary syndrome (PCOS), however little is known about how androgens affect early preantral follicle development. Recent evidence suggests that androgens may act, in part, through non-classical modulation of growth factor signalling pathways. Members of the epidermal growth factor (EGF) family play a role in promoting preantral follicle development in the mouse, with receptor subtypes EGFR, ErbB2...

Polycystic ovary syndrome, a common endocrine condition affecting up to 10% of women of reproductive age, is associated with an increased risk of developing insulin resistance and obesity. Obesity is associated with increased energy intake or reduced energy expenditure. In this context, postprandial thermogenesis (PPT), is an important constituent of energy expenditure.Our lab utilizes a clinically realistic ovine model of PCOS, where pregnant Scottish G...

Introduction: Primordial follicles are relatively quiescent structures that form the basis of the ovarian reserve. Maintenance of the quiescent state, and conversely, release from this state towards irreversible growth, involves mechanisms that are currently unresolved. Two transcription factors have been implicated alongside this process in granulosa cells (GCs). Specifically, Smad3 was recently identified in the nuclei of GCs in small single-layered follicles whereas Foxl2 i...

Women with Polycystic Ovary Syndrome are at increased risk of developing insulin resistance, obesity and dyslipidemia. Amplified metabolic perturbations during puberty may be a central factor contributing to metabolic phenotype of adult PCOS. Using a clinically realistic ovine model of PCOS we reported hyperinsulinaemia and early fatty liver changes, with no difference in body weight and adiposity, in adolescence.Here we aimed to further examine metaboli...