Reproduction Abstracts

Premature ovarian failure (POF) affects ~1% of women over 40 and is idiopathic in 74–90% of cases. A transgenic mouse model of POF has been generated (known as double mutant; DM) resulting from oocyte-specific deletion of two glycosyltransferases. Glycoproteins from DM oocytes lack complex O- and N-glycans. DM females are fertile at 6-weeks, infertile by 9-weeks and exhibit POF by 12-weeks of age with follicle depletion, elevated gonadotropins and decrea...

Introduction: The regulation of follicle development is not well understood, despite its importance in determining fertility, but there is evidence that the oocyte plays a key role. The female C1galt1 Mutant mouse has an oocyte-specific deletion of the T-synthase enzyme and as a result cannot synthesise core 1-derived O-glycans. Mutant females exhibit a phenotype of increased fertility and altered follicle development. To investigate the hypothesis that changes in the developm...

Introduction: A role for oocyte core 1-derived O-glycans in the regulation of ovarian follicle development has previously been shown using the C1galt1F/F:ZP3Cretransgenic mouse model. In this model, oocyte-specific ablation of core 1-derived O-glycans results in a sustained increase in ovulation rate and fertility, which is hypothesized to be due to changes in follicle development. In this study, we sought to characterise the role of oocyte core 1-derived O-glycans ...

Introduction: Follicle development is complex, and the use of reaggregated ovaries (ROs) allows us to investigate oocyte-somatic cell interactions, since they can be created using different sources of germ and somatic cells. Production of an RO involves the separation of germ and somatic cells using differential plate adhesion, followed by reaggregation into a pellet. The pellet is then transplanted beneath the kidney capsule of an immunocompromised mouse which facilitates fol...

Premature ovarian failure (POF) affects around 1% of women and is idiopathic in 74–90% of cases. Our mouse model of POF, the double mutant (DM), are fertile at 6-weeks and undergo POF by 3-months consistent with a decline in developing follicles. However, DM ovaries have increased numbers of primary follicles at the 3a stage, indicating a block in follicle development.We investigated whether we could rescue the ability of DM oocytes at 3- and 9-week...

The oocyte influences hormonal and cellular changes in the follicle and the ovary. Theca cells, surrounding the follicle basement membrane, synthesise androgen and thus regulate ovarian oestrogen production. The vascular theca layer provides nutrients to the avascular inner follicle. In C1galt1 mutant mice, all oocytes lack core 1-derived O-glycans due to oocyte-specific ablation of core 1 beta 1,3-galactosyltransferase. C1galt1 mutants have increase...

Introduction: Premature ovarian failure (POF) is a reproductive disorder which causes defects within the ovaries, normally leading to infertility. The disorder affects 1% of women under the age of 40 with 75% of cases with no known cause, indicating the need for more research. The Double Mutant (DM) mouse model with oocyte-specific deletion of C1galt1 and Mgat1 exhibit follicular POF at 3 months of age. Therefore, this study aimed to investigate the effect of ovarian dysfuncti...

Introduction: Premature ovarian failure (POF) is a condition that affects ~1% of women and is idiopathic in 74–90% of cases. Our mouse model of POF, the Double Mutant (DM), results from oocyte-specific ablation of core 1-derivedO-glycans and complex and hybrid N-glycans. DM females are subfertile at 6-weeks of age and infertile at 9-weeks of age. By 3 months, DM females exhibit POF with ovaries containing fewer developing follicles but more primary 3a follicles. We invest...

Each egg, when ovulated from a follicle, is surrounded by cumulus cells. Prior to ovulation, these cumulus cells secrete cumulus extracellular matrix (cECM) molecules, resulting in cumulus expansion. Cumulus expansion has been linked to the developmental quality of the oocyte. Hyaluronan (HA), the major constituent of the cECM, is stabilised by molecules such as heavy chains (HCs), pentraxin 3 (PTX3) and tumour necrosis factor-stimulated gene 6 (TSG6) during expansion. All of ...