Effects Of Leptin On Follicle Growth And Ovulation
Funder
National Health and Medical Research Council
Funding Amount
$196,470.00
Summary
Leptin is a recently discovered hormone which is very important in controlling body weight. Extremely obese, or extremely underweight women, find it difficult to become pregnant, and leptin is probably the connection between weight and fertility. This may be a particularly important factor in polycystic ovary syndrome (PCOS), a distressing condition which affects 5% of women and causes both obesity and infertility. Exciting new research suggests that leptin also affects the immune system, and pr ....Leptin is a recently discovered hormone which is very important in controlling body weight. Extremely obese, or extremely underweight women, find it difficult to become pregnant, and leptin is probably the connection between weight and fertility. This may be a particularly important factor in polycystic ovary syndrome (PCOS), a distressing condition which affects 5% of women and causes both obesity and infertility. Exciting new research suggests that leptin also affects the immune system, and previous NH and MRC funding has enabled us to demonstrate that the immune system plays a crucial role in maintaining normal ovarian function. The nutritional status of the body, the immune system and the reproductive system all interact, and leptin appears to be the connecting link between these three major systems. We propose that leptin plays a major role in the ovary, and wish to determine how leptin mediates the effects of bodyweight and the immune system on ovarian function. Laboratory rats will be treated with leptin, their food intake and weight recorded, and a few weeks later the rats will have their ovaries removed. We will find out whether ovaries respond to leptin, or whether the ovarian response changes according to the menstrual cycle: perhaps leptin is very important just before ovulation, but it does not affect menstruation? Do any ovarian cells make leptin? Will leptin stimulate ovaries to produce more oestrogen or progesterone, or ovulate more eggs? We will also identify immune system cells in the ovary, and note whether leptin affects them. We will be able to relate all this data to weight and diet. Increased understanding of leptins' effect on the ovary has the potential to lead to new, improved treatments for PCOS or for unexplained cases of infertility. It is also possible that in the future a weight-loss regime might be developed which takes a womans monthly cycle into account, therefore making weight-loss more efficient and attainable.Read moreRead less
The Role Of Oocyte-secreted Proteins In Primate Follicular Cell Function
Funder
National Health and Medical Research Council
Funding Amount
$176,320.00
Summary
Mammalian eggs grow and develop in fluid filled sacks in the ovary called follicles. These structures nurture the egg for prolonged periods preparing it for ovulation and fertilisation. It has been known for some time that the quality of the follicular environment determines, in part, the developmental potential of the egg. Recent studies in mice have shown that the interaction between the egg and the follicle is in fact a two-way process, and that the egg is able to influence development of the ....Mammalian eggs grow and develop in fluid filled sacks in the ovary called follicles. These structures nurture the egg for prolonged periods preparing it for ovulation and fertilisation. It has been known for some time that the quality of the follicular environment determines, in part, the developmental potential of the egg. Recent studies in mice have shown that the interaction between the egg and the follicle is in fact a two-way process, and that the egg is able to influence development of the follicle. This project proposes to investigate these processes further in the laboratory mouse using new reagents available to us, and to extend these findings by investigating this communication pathway for the first time in a primate species. Because of the difficulty of undertaking such research using human material, we will use the marmoset monkey as a model. This exciting new development has important implications for women's health because it may help us understand why some women suffer from premature menopause or cystic ovaries, and in the longer term could help in the development of new types of contraceptives.Read moreRead less
Gonadotropin Inhibitory Hormone As A Major Regulator Of Reproduction In Mammals
Funder
National Health and Medical Research Council
Funding Amount
$623,378.00
Summary
Reproduction is controlled by the brain and it has been well established that gonadotropin releasing hormone (GnRH) is the primary stimulatory factor. GnRH stimulates the pituitary gland to produce and secrete hormones that, in turn, stimulate the ovaries and testes. It is becoming clear that the brain also produces an inhibitory factor and this project aims to establish that it (gonadotropin inhibitory hormone; GnIH) is functional in mammals.
Cohesin: Role In Germ Cell Chromosomal Segregation
Funder
National Health and Medical Research Council
Funding Amount
$435,526.00
Summary
At least 10 to 25% of all human fetuses have the wrong number of chromosomes (aneuploidy). Most of these abormal fetuses perish in utero, making it the leading known cause of early pregnancy loss. Aneuploidy is the leading genetic cause of developmental disabilities and mental retardation. Abundant evidence suggests that most of these chromosome abnormalities originate during unequal partitioning of genetic material (chromosomes) in eggs and sperm. The proposed project focuses on two related gen ....At least 10 to 25% of all human fetuses have the wrong number of chromosomes (aneuploidy). Most of these abormal fetuses perish in utero, making it the leading known cause of early pregnancy loss. Aneuploidy is the leading genetic cause of developmental disabilities and mental retardation. Abundant evidence suggests that most of these chromosome abnormalities originate during unequal partitioning of genetic material (chromosomes) in eggs and sperm. The proposed project focuses on two related genes, called Rec8 and Rad21, which we recently discovered in humans and mice. Due to that these genes are essential for chromosome separation in other species and they exists in species as diverse as yeast and humans, they may be responsible for accurate separation of chromosomes in germ cells in mammals. In this proposal, we will determine the role(s) of these molecules in controlling proper chromosome segregation by loss-of-function studies in genetically engineered mice lacking Rec8 and Rad21 genes. By analyzing the chromosomal abnormalities of the cells from these animals, we will gain critical information about the nature of chromosome partitioning disorders in humans.Read moreRead less
Diet And Exercise Intervention For Paternal Obesity Improves Offspring Health
Funder
National Health and Medical Research Council
Funding Amount
$678,481.00
Summary
Obesity is a growing problem in Western Society and is associated with a large number of metabolic conditions. There is an increasing awareness that a fathers health at the time of conception affects fertility and also the ongoing health of the pregnancy and the ofspring. This study seeks to determine if diet and exercise intervention for overweight or obese males can improve the health of the sperm and therefore the ability to father a pregnancy and the health of the offspring.
Endometrial Receptivity For Embryo Implantation: Proprotein Convertase 6 And Plasma Membrane Remodeling
Funder
National Health and Medical Research Council
Funding Amount
$631,344.00
Summary
Implantation of an embryo into the uterus is a key step in establishing pregnancy; it requires a receptive uterus (fertile soil) and a healthy embryo (seed). Implantation failure causes pregnancy loss and infertility, and is also a major limiting factor in IVF. We have established that proprotein convertase 6 (PC6) is a master regulator of uterine receptivity for implantation. We will investigate how PC6 works in a woman’s uterus, and how we can use this knowledge to improve implantation in IVF.