Obesity And Infertility: Effects Of Diet-induced Insulin Resistance On Oocyte Quality.
Funder
National Health and Medical Research Council
Funding Amount
$533,510.00
Summary
The health of an embryo (and subsequently child) is largely determined by the health of the mother. It is well documented that women who have poor pre-pregnancy health due to obesity are more likely to have difficulty conceiving due to irregular ovulations and early embryo loss. My research using obese mice has found that these fertility problems are partly due to alterations in the oocytes (eggs) within the ovary. Its surrounding cells and fluid provide the oocyte with all of its required nutri ....The health of an embryo (and subsequently child) is largely determined by the health of the mother. It is well documented that women who have poor pre-pregnancy health due to obesity are more likely to have difficulty conceiving due to irregular ovulations and early embryo loss. My research using obese mice has found that these fertility problems are partly due to alterations in the oocytes (eggs) within the ovary. Its surrounding cells and fluid provide the oocyte with all of its required nutrients. I hypothesize that this follicular environment is altered in females that are obese leading to inappropriate nutritional signals and suboptimal development of the oocyte. The goals of my research are to use obese mice to 1) pinpoint exactly which metabolic alterations lead to decreased oocyte development; 2) determine how these metabolic alterations change the oocyte and the cells surrounding it; 3) use the information gained to analyse ovarian cells of women and see if these same alterations occur in women who are obese. The findings will be highly significant because they will 1) provide a greater understanding of how the maternal environment communicates nutritional information to the oocyte, which ultimately forms the developing embryo. 2) expand our knowledge of the optimal nutritional conditions for oocyte and early embryo development. 3) identify biological mechanisms that are altered during obesity and lead to decreased female fertility. 4) aid in the development of improved agents for use at fertility clinics, for instance the development of solutions most closely mimicking the critical components of the normal ovarian environment, for use in the culture of oocytes and embryos. 5) provide a strong public health message to women of reproductive age: to achieve and maintain a healthy body weight prior to becoming pregnant.Read moreRead less
Insulin Resistance In Polycystic Ovary Syndrome And The Role Of Skeletal Muscle And Adipose Tissue
Funder
National Health and Medical Research Council
Funding Amount
$416,115.00
Summary
11% of women have polycystic ovarian syndrome(PCOS), characterised by insulin resistance, irregular periods and infertility. These women are prone to obesity, diabetes and potentially, heart disease. Treatments include lifestyle modifications +-- medical therapy. Lifestyle is first line, yet the best diet-exercise prescription is unclear. This study will provide insights into the cause of PCOS, will inform on the role of exercise in therapy and may identify targets for future therapies.
Progesterone Receptor-mediated Coordination Of Oocyte-oviduct Communication During Ovulation
Funder
National Health and Medical Research Council
Funding Amount
$86,128.00
Summary
Infertility affects 1 in 6 couples, often due to failed release of an egg from the ovary. The hormone progesterone is essential for this process. Our goal is to determine how progesterone signals the egg to ensure its correct release into the oviduct where fertilization may occur. To identify these signals, experiments will analyse ovary cells and eggs of mice, including mice that do not respond to progesterone. The results will provide much needed information about female reproductive health.
Polycystic ovary syndrome (PCOS) affects 5-10% of women worldwide, yet its origins remain unknown. Androgens are implicated in the development of PCOS, but the decisive, invasive studies needed to confirm and elucidate their roles are not feasible in women. Hence, using our innovative mouse models of androgen resistant female mice, this study will determine the role of androgens in PCOS aiming to better understand, and identify new treatments for this common female reproductive disorder.
Hormonal Control Of Serotli Cell Maturation And Function
Funder
National Health and Medical Research Council
Funding Amount
$512,898.00
Summary
This project will determine the key roles of androgen in the Sertoli cell, a unique highly specialised cell that provides essential nutritional and structural support for sperm production. Androgen acts via the androgen receptor (AR), which is vital for initiating and maintaining sperm development. In current NHMRC-funded research we successfully established new mouse models designed to study AR, in particular its regulation of gene expression, in the Sertoli cell. We revealed that genomic AR ac ....This project will determine the key roles of androgen in the Sertoli cell, a unique highly specialised cell that provides essential nutritional and structural support for sperm production. Androgen acts via the androgen receptor (AR), which is vital for initiating and maintaining sperm development. In current NHMRC-funded research we successfully established new mouse models designed to study AR, in particular its regulation of gene expression, in the Sertoli cell. We revealed that genomic AR activity within Sertoli cells is essential for 'induction' of complete sperm development. Ongoing work will develop unique 'inducible' transgenic models that will allow, for the first time, selective analysis of Sertoli AR in both 'developing' and 'adult' testes. Our innovative models will allow AR function to be switched on or off at any stage of development, providing unique opportunity to determine the key AR-regulated factors and pathways controlling induction, maintenance or restoration of sperm production. In past NHMRC research we created a novel transgenic model to study another major reproductive hormone, FSH. Using the hormone-deficient background of 'hpg' mice, we found that androgen and FSH act synergistically in the developing 'meiotic' germ cells that form sperm. Using the latest microarray gene technology we generated datasets of androgen-regulated genes with or without FSH activity, which combined with our unique transgenic AR and FSH models, will be used to identify key pathways, including those enhanced by androgen-FSH synergism, in the early testicular response. Our research will provide new knowledge of the precise roles and pathways of testicular AR actions, to ultimately identify key genetic and regulatory factors as targets for significantly improved therapy for male infertility, gonadal tumours, or contraception.Read moreRead less
This study is aiming to develop an unique mouse model in which to study the question whether testosterone plays an essential role in female reproductive and general health. It will develop a genetic mouse model for a biological state of complete resistance to the effects of androgens. Such mice and humans are well known among genetic males but this cannot occur naturally among genetic female mammals. By creating such a mouse line, this project will be able to test for the first time indetail whe ....This study is aiming to develop an unique mouse model in which to study the question whether testosterone plays an essential role in female reproductive and general health. It will develop a genetic mouse model for a biological state of complete resistance to the effects of androgens. Such mice and humans are well known among genetic males but this cannot occur naturally among genetic female mammals. By creating such a mouse line, this project will be able to test for the first time indetail whether testosterone has an impotant role in the development and function of the ovary and of other female tissues such as bone, muscle and the brain.Read moreRead less