Neuroendocrine Mechanisms By Which Leptin Regulates Reproduction
Funder
National Health and Medical Research Council
Funding Amount
$447,750.00
Summary
The reproductive system is sensitive to alterations in body weight. In particular, low body weight causes the reproductive system to cease functioning. This is because the brain 'senses' metabolic status and responds by ceasing to secrete the brain hormone that drives the reproductive process. This hormone is gonadotropin releasing hormone that acts on the pituitary gland to control the release of gonadotropins. These, in turn, act on the gonads. How the brain perceives metabolic status is not k ....The reproductive system is sensitive to alterations in body weight. In particular, low body weight causes the reproductive system to cease functioning. This is because the brain 'senses' metabolic status and responds by ceasing to secrete the brain hormone that drives the reproductive process. This hormone is gonadotropin releasing hormone that acts on the pituitary gland to control the release of gonadotropins. These, in turn, act on the gonads. How the brain perceives metabolic status is not known. Leptin is a hormone that is produced by fat and acts on the brain. This appears to be one of the means by which the reproductive system is regulated. Leptin also regulates food intake and other brain processes. Leptin acts on specific cell types in the brain. Some of these may have dual function to regulated appetite as well as reproduction. The present proposal is for work to determine mechanisms within the brain that are altered by leptin. We will also determine which specific mechanisms relate to the regulation of gonadotropin releasing hormone. The work will provide information on how putative appetite regulators might affect the reproductive axis. Such work will provide a platform for design of pharmaceutical means to manipulate the reproductive axis and will impact on the design of drugs that regulate obesity. It is possible that drugs that developed to control obesity may affect the reproductive axis and the project will identify these.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.
The Sertoli Cell: Master Regulator Of Hormone-induced Spermatogenic Development
Funder
National Health and Medical Research Council
Funding Amount
$563,536.00
Summary
This project will determine the key roles of major hormones (testosterone, follicle-stimulating hormone, Vitamin A) in Sertoli cells, unique highly specialised cells found in the testis that provide essential nutritional and structural support for sperm production. This research will provide new understanding of the biological pathways controlling sperm development, leading to new molecular targets for infertility or cancer treatment or diagnosis, or new contraceptive strategies for men.
The Function Of Gametogenenin In Male Fertility And Embryogenesis
Funder
National Health and Medical Research Council
Funding Amount
$537,579.00
Summary
We have identified gametogenetin as novel protein involved in sperm production and in the very earliest stages of embryo survival. It is found within the sperm tail where it binds to cysteine-rich secretory protein 2. The aim of this project is to further refine the biochemistry of GGN using a combination of binding studies, expression analyses and the characterization of two unique mouse models. This project has direct relevance to the causes of human infertility and contraceptive development.
A New Model Of Asthenospermia And A Candidate Gene For Multiple Ciliopathies
Funder
National Health and Medical Research Council
Funding Amount
$629,039.00
Summary
Though the analysis of a unique mouse strain (Mot1) we have identified a previously unknown cause of male infertility and lung disease. We hypothesis that the Mot1 line is a model of human primary cilia dyskinesia and that the Mot1 protein is involved in cilia function. Within this project we will define the consequences of a loss of Mot1 protein function, we will define its binding partners and we will screen for mutations in the corresponding human gene.
Kisspeptin And Its Receptor Mastermind Reproduction
Funder
National Health and Medical Research Council
Funding Amount
$601,979.00
Summary
Reproduction is controlled by the brain and gonadotropin releasing hormone (GnRH) is the primary stimulatory factor. Finding critical regulators of GnRH has remained the most important goal for reproductive endocrinologists for over 30 years. The brain peptide hormone called kisspeptin and its receptor Kiss1R appear vital in the control of reproduction. This project will detail the role kisspeptin and Kiss1R play in controlling hormones from the brain that govern puberty and reproduction.
The Identification Of Male Meiosis Genes Using A New Mouse Line And Human Genome Scans For Gene Copy Number Variations
Funder
National Health and Medical Research Council
Funding Amount
$604,793.00
Summary
Infertility affects 1 in 25 Australian men and meiosis is a key process in male fertility, yet we know very little about the mechanisms that control it. We will use a new point mutant mouse model of meisois failure to identify a novel regulator of male fertility. Further, we hypothesize that changes in gene copy number will lead to meiosis arrest and infertility in some men. Such variations will be assessed through a whole genome scan of a unique set of infertile men.