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
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.
Cysteine-rich Secretory Protein Regulation Of Ion Channels In Male Fertility And Prostate Cancer
Funder
National Health and Medical Research Council
Funding Amount
$474,309.00
Summary
Diagnosis of the precise causes of male infertility and the development of male contraceptives requires improved understanding of sperm function. The Cysteine-Rich Secretory Proteins (CRISPs) are produced in the male reproductive tract where they regulate sperm function. Our project will demonstrate the essential requirement for CRISPs in sperm function and investigate their role in other tissues of the reproductive tract, including the prostate where they may be involved in prostate cancer.
The Formation And Development Of The Ovarian Follicular Membrana Granulosa
Funder
National Health and Medical Research Council
Funding Amount
$351,575.00
Summary
In order for the ovary to be able to release eggs and produce hormones such as oestrogen, follicles must grow within the ovary. Each follicle contains one egg and when the follicle is large and filled with fluid it can rupture, releasing the fluid and egg in the process of ovulation. A key part of the structure of the follicle is a non-cellular layer called the basal lamina. This basal lamina encapsulates the inner cells, the egg and the fluid in the follicle. Each women has millions of follicle ....In order for the ovary to be able to release eggs and produce hormones such as oestrogen, follicles must grow within the ovary. Each follicle contains one egg and when the follicle is large and filled with fluid it can rupture, releasing the fluid and egg in the process of ovulation. A key part of the structure of the follicle is a non-cellular layer called the basal lamina. This basal lamina encapsulates the inner cells, the egg and the fluid in the follicle. Each women has millions of follicles prior to her birth, ten of thousands in her reproductive years, and none at the menopause. Since she only ovulates about 500 in her lifetime most follicles die in the process of growing to ovulatory size. This project will examine the structure of the follicle wall and the cells that make up that wall. How these cells replicate during follicle growth has never been discovered. This research has important implications for the many women who have polycystic ovarian disease, whose follicles fail to grow to full size. We will be examining these ovaries directly. The research also has importance in the next phase of IVF developments.Read moreRead less
Role Of Tumour Suppressor Genes In Early Embryopathy
Funder
National Health and Medical Research Council
Funding Amount
$408,000.00
Summary
Assisted reproductive technologies (ART, such as IVF and related techniques) are successful treatments for most forms of infertility. Much of this is due to the high mortality of the resulting embryos. Typically, 45-80% of embryos produced by ART do not survive the first week. The high mortality of the early embryo seems to be a general feature of ART but its causes and effectors are incompletely defined. It has been established that this high mortality is largely due to a marked retardation in ....Assisted reproductive technologies (ART, such as IVF and related techniques) are successful treatments for most forms of infertility. Much of this is due to the high mortality of the resulting embryos. Typically, 45-80% of embryos produced by ART do not survive the first week. The high mortality of the early embryo seems to be a general feature of ART but its causes and effectors are incompletely defined. It has been established that this high mortality is largely due to a marked retardation in the rate of cell cycle progression by embryo cells, and commonly is associated with a form of cell 'suicide', known as apoptosis. In non-embryonic cells a group of genes known as the tumour suppressor genes (TSGs) are responsible for slowing cell-cycle progression and are commonly involved in inducing apoptosis following cell stress. The role of TSGs in the early embryo is not well studied. We have recently shown that the most important of the TSGs, P53, is normally kept at very low levels in the early embryo but that ART causes up-regulation of its expression. This upregulation is a major cause of the embryopathy associated with ART in an animal model but that genetic mutations that prevent P53 expression favours increased embryo development and viability. This project will examine whether ART also causes up-regulation other important TSGs and whether this occurs in human embryos. We will examine the hypothesis that ART increases the survival of embryos with mutations to the P53 gene (creating a postive genetic selection pressure in favour of these mutations); and which aspects of ART cause this positive selection. The project will demonstarte whether changes in the ART procedures have the potential to mitigate against selection of embryos bearing deletrious mutations.Read moreRead less
This project aims to study how the two main hormones, FSH and testosterone, control the development and production of sperm throughout adult life. In previous NHMRC-supported research we were the first to overturn the long-standing belief that FSH was vital to the start of sperm production in all warm-blooded animals. This insight was achieved from experiments using a genetically modified strain of mouse. We used this mouse strain to develop a new experimental paradigm to provide unique insight ....This project aims to study how the two main hormones, FSH and testosterone, control the development and production of sperm throughout adult life. In previous NHMRC-supported research we were the first to overturn the long-standing belief that FSH was vital to the start of sperm production in all warm-blooded animals. This insight was achieved from experiments using a genetically modified strain of mouse. We used this mouse strain to develop a new experimental paradigm to provide unique insight into how hormones start up and support sperm production. In this present proposal we wish to take this research further. Although we have shown that FSH is not vital to the startup or continuing of sperm production, we believe it still does have an important role in causing the growth of a large enough population of Sertoli cells of the testis. These highly specialised cells have the unique job to support, nourish and coordinate the production of sperm. Sertoli cells are known to be the only target in the body for FSH and so that FSH must act upon them exclusively. We believe this occurs almost solely during early life - starting before birth and into early infancy - well before adult life when sperm are produced for the first time. In this way these processes being studied determine the size of mature testis. Our new approaches to studying the question of how the two main hormones control sperm production involve developing new types of genetically modified mice which have extra and exclusive FSH activity as well as some new research methods to be applied to understanding how FSH acts on the Sertoli cell using techniques derived from gene therapy and from cell transplantation. This research has the possibility to uncover new causes of previously unexplained male infertility (the majority having no known cause so far), to help develop better hormonal male contraceptives, and to quetion the need for expensive treatments for some infertile men.Read moreRead less