Of Mice And Men: Assessing Dietary Proteins Role On Appetite Regulation, Obesity And Cardiovascular Risk
Funder
National Health and Medical Research Council
Funding Amount
$86,521.00
Summary
While the challenge of understanding and managing the global obesity epidemic is well recognised, the role that nutrition plays is more complex than at first glance. Dietary protein may be of central importance in managing weight and small changes in protein consumption may lead to large changes in energy intake and weight. We propose to look at the effects of dietary protein on appetite, its hormonal regulation, and on the risk of developing metabolic diseases such as diabetes.
Pathways Involved In The Insulin-like Growth Factor (IGF)-independent Actions Of IGF Binding Protein-6
Funder
National Health and Medical Research Council
Funding Amount
$550,725.00
Summary
Insulin-like growth factors (IGFs) are important proteins that regulate growth. When not regulated properly, diseases such as cancer can occur. A family of IGF binding proteins regulates IGFs. IGFBPs may inhibit IGFs and we have shown that one of them, IGFBP-6, decreases growth of some experimental cancers. As well as regulating IGFs, some IGFBPs alter cell behaviour independently of IGFs, and we found that IGFBP-6 stimulates cell movement in this way. We will now determine how this happens.
Endocrine And Autocrine Regulation Of Breast Cancer Cell Growth By IGF Binding Protein-3 (IGFBP-3).
Funder
National Health and Medical Research Council
Funding Amount
$497,250.00
Summary
The insulin-like growth factor (IGF) system of growth factors and their regulatory proteins is essential for normal growth, but is also involved in a number of overgrowth disorders. Some clinical studies have shown that a high level of IGF-I in the blood increases the risk of breast cancer in some women, but if the protein which carries it in the circulation, IGFBP-3, is also high, the risk is reduced. It has therefore been suggested that IGFBP-3 may be useful in the treatment of breast cancer. ....The insulin-like growth factor (IGF) system of growth factors and their regulatory proteins is essential for normal growth, but is also involved in a number of overgrowth disorders. Some clinical studies have shown that a high level of IGF-I in the blood increases the risk of breast cancer in some women, but if the protein which carries it in the circulation, IGFBP-3, is also high, the risk is reduced. It has therefore been suggested that IGFBP-3 may be useful in the treatment of breast cancer. This is supported by laboratory studies showing that IGFBP-3 can inhibit cell division and stimulate cell death in many cell types, including breast cells. However, some cells are resistant to IGFBP-3 s inhibitory effects, and in some cases IGFBP-3 may stimulate cells to grow and divide. In fact, the amount of IGFBP-3 present in breast tumours is highest in the fastest growing, most malignant tumours, suggesting that IGFBP-3 may be stimulating their growth. Our laboratory data indicates that breast cancer cells which produce a high level of IGFBP-3 grow faster as tumours than cells which produce little or no IGFBP-3. We believe that this is because IGFBP-3 interacts with another hormone system which is involved in rapid tissue growth, the EGF system, and increases its ability to stimulate breast cells to divide. These observations raise a number of important questions: how does IGFBP-3 interact with the EGF system to stimulate tumour growth; does IGFBP-3 from the blood promote the growth of EGF-sensitive tumours; and can the interaction between IGFBP-3 and the EGF system be abolished, or switched from growth stimulatory to growth inhibitory, thus inhibiting tumour growth. Answering these questions will provide important new information regarding IGFBP-3 s stimulatory and inhibitory actions, and the role of endocrine IGFBP-3 in tumour growth, and have the potential to lead to the development of novel therapies involving IGFBP-3 for the treatment of overgrowth disorders.Read moreRead less
Determinants Of Insulin-like Growth Factor (IGF) Binding And Biological Actions Of IGF Binding Protein-6
Funder
National Health and Medical Research Council
Funding Amount
$399,750.00
Summary
Proteins are complex structures usually consisting of a number of distinct regions. Each of these regions may serve different roles. Insulin-like growth factors (IGFs) are important proteins involved in regulating the growth and other properties of cells. The actions of IGFs are in turn regulated by a family of binding proteins (IGFBPs). The aim of this project is to determine the range of actions of one of these IGFBPs and which parts of this IGFBP are involved in these actions. This may lead t ....Proteins are complex structures usually consisting of a number of distinct regions. Each of these regions may serve different roles. Insulin-like growth factors (IGFs) are important proteins involved in regulating the growth and other properties of cells. The actions of IGFs are in turn regulated by a family of binding proteins (IGFBPs). The aim of this project is to determine the range of actions of one of these IGFBPs and which parts of this IGFBP are involved in these actions. This may lead to new treatments for diseases in which cell growth is disturbed e.g. cancer and diabetes.Read moreRead less
Regulation And Effect Of The Growth Hormone, IGF-I, And IGF-Binding Protein Response To Acute Exercise
Funder
National Health and Medical Research Council
Funding Amount
$367,197.00
Summary
The body's ability to respond to physiological stress is vital to survival. This series of studies aims to examine the hormonal responses to physical exercise. In studies recently completed to determine how to detect Growth Hormone (GH) abuse in the Olympics, we have discovered a new system of hormones that respond to exercise. These Insulin-like Growth Factors (IGF) and their IGF-Binding Proteins (IGF-BP) are normally controlled by GH. The IGF-IGF-BP system normally acts to control of many cell ....The body's ability to respond to physiological stress is vital to survival. This series of studies aims to examine the hormonal responses to physical exercise. In studies recently completed to determine how to detect Growth Hormone (GH) abuse in the Olympics, we have discovered a new system of hormones that respond to exercise. These Insulin-like Growth Factors (IGF) and their IGF-Binding Proteins (IGF-BP) are normally controlled by GH. The IGF-IGF-BP system normally acts to control of many cellular and organ functions in many different tissues of the body. For example they stimulate protein accumulation and muscle growth, and have actions to control blood glucose in conditions like diabetes. Little is known about what regulates the production of the IGF and IGF-BPs in response to physical exercise. We aim to examine whether GH, either as an acute pulse as occurs naturally, or a direct effect of exercise that is not GH-mediated, is responsible for the increase in IGF and IGFBPs. This may uncover a new means of controlling this powerful hormonal system. In addition, we will examine whether GH or IGF-I, alone and together, influence the body's ability to respond to the stress of exercise (e.g., controlling fuel use, cardiovascular and kidney responses). Such information will allow greater understanding of this important hormonal system, so that in novel therapies may be developed for conditions such as normal ageing, the wasting states that accompany severe surgical or infectious stress, or conditions with abnormal blood glucose regulation such as diabetes. In addition, this information will permit greater sophistication in the detection of GH and related compounds in elite athletes. Unfortunately, GH is also being abused by non-elite athletes and high-school children. We believe our efforts will asist in the detection and prevention of these more general societal health issues.Read moreRead less
Characterisation Of A Novel Prostate-expressed Kallikrein-like Protease And Its Target Proteins
Funder
National Health and Medical Research Council
Funding Amount
$724,544.00
Summary
Prostate disease is common in most men in later life and can affect their quality of life adversely. The primary conditions are benign prostatic hyperplasia or BPH and prostate cancer. Symptoms of BPH affect between 50-70% of men over the age of 50 and prostate cancer is now the most common internal cancer diagnosed in men. More importantly, prostate cancer is the second most common cause of cancer deaths. We don't yet fully understand exactly how these diseases occur but the male sex hormones o ....Prostate disease is common in most men in later life and can affect their quality of life adversely. The primary conditions are benign prostatic hyperplasia or BPH and prostate cancer. Symptoms of BPH affect between 50-70% of men over the age of 50 and prostate cancer is now the most common internal cancer diagnosed in men. More importantly, prostate cancer is the second most common cause of cancer deaths. We don't yet fully understand exactly how these diseases occur but the male sex hormones or androgens are known to play an important role. Prostate specific antigen or PSA has become widely accepted as a useful tool in helping to detect prostate cancer and then monitoring the disease. PSA, which is regulated by androgens, is an enzyme that either activates or breaks down many proteins that are important in both the normal function of the prostate and in the development of cancer. PSA belongs to a family of enzymes called the kallikreins. We have recently discovered a new member of this family that, like PSA, is also found in the prostate. We have called this new enzyme, K6, as it is the sixth member of this family to be identified. So , this project is about characterising this new K6 enzyme, finding out if it is also found in the prostates of men with BPH and prostate cancer, whether it is also regulated by androgens and what sort of proteins it may activate in these diseases. We will also compare these findings with what we know about PSA in these diseases. From these studies, we will not only understand more about this K6 enzyme and how it might be important in the prostate but also how it relates to PSA. These findings may ultimately lead to some new approaches in the detection and treatment for BPH and prostate cancer.Read moreRead less
Regulation And Functional Roles Of ADAM 10 Protease In Prostate Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$465,750.00
Summary
Prostate cancer is the second most common cause of cancer death among western males. Most deaths from prostate cancer are due to the development of secondary tumours (metastases) in other body organs. Metastasis involves actions of enzymes, (called metalloproteinases) which can break down the tissue structure surrounding tumour cells, and actions of a family of proteins (called integrins)that control how cells stick to each other or to other tissue components. Both these actions allow tumour cel ....Prostate cancer is the second most common cause of cancer death among western males. Most deaths from prostate cancer are due to the development of secondary tumours (metastases) in other body organs. Metastasis involves actions of enzymes, (called metalloproteinases) which can break down the tissue structure surrounding tumour cells, and actions of a family of proteins (called integrins)that control how cells stick to each other or to other tissue components. Both these actions allow tumour cells to break free from their original tissue positions, walk through surrounding tissue and deposit themselves at distant sites to form a secondary tumour. In this research we are looking at a protein, called ADAM-10, which belongs to a family of proteases, the ADAMs, which contain both A Disintegrin And Metalloprotease activity, hence their name. Our data suggest ADAM-10 is produced in large quantities by prostate cancer cells but can be differently located within these cells it sits on the outer membrane of normal or benign prostate glands but re-locates to the cell nucleus in high grade prostate cancer cells. We have also identified ADAM-10 protein in small membrane fragments that are commonly shed from prostate cancer cells. Preliminary evidence suggests that levels of ADAM-10 in each of these locations is regulated by growth factors and-or the male sex hormone, androgen, key hormones involved in prostate cancer growth and progression. We do not yet know what actions ADAM-10 has when it occurs in these different locations but believe the membrane form will be involved in metastasis, with the nuclear form being involved in regulating events within the nucleus, the control centre for the cell. This grant application aims to build on our novel observations and investigate the underlying mechanisms of ADAM-10 hormonal regulation and function. If proven, these issues may be important for the development, progression and future treatment of prostate cancer.Read moreRead less
Role Of The Nuclear Growth Hormone Receptor In Cell Proliferation And Function
Funder
National Health and Medical Research Council
Funding Amount
$477,750.00
Summary
In addition to final height, growth hormone regulates many tissues in the body, and through these, regulates metabolism, body composition, vitality and aspects of ageing. However, there is some evidence that GH can also promote cancer, notably colon and blood cell cancers. Our discovery of the receptor for growth hormone in the cell nucleus, notably in many cancers, has led us to investigate the role of the nuclear GH receptor. We have found that targeting this receptor to the nucleus allows the ....In addition to final height, growth hormone regulates many tissues in the body, and through these, regulates metabolism, body composition, vitality and aspects of ageing. However, there is some evidence that GH can also promote cancer, notably colon and blood cell cancers. Our discovery of the receptor for growth hormone in the cell nucleus, notably in many cancers, has led us to investigate the role of the nuclear GH receptor. We have found that targeting this receptor to the nucleus allows the cell to divide without the need for the normal factors which initiate cell division and survival. We have also found that a part of the GH receptor acts as a gene activator, and have identified some of the nuclear proteins which bind to the receptor and make this so. This proposal aims to establish the link between the nuclear GH receptor and cell division, both mechanistically, and in live animals. We also plan to establish if nuclear localizing the receptor artificially results in cancer formation. The outcome would provide an index of risk from current GH therapy, and could lead to a new cancer therapy.Read moreRead less
Focimatrix Regulation Of Sex Steroid Hormones In The Ovary
Funder
National Health and Medical Research Council
Funding Amount
$291,309.00
Summary
Sex steroid hormones (e.g. oestrogen and testosterone), are important to male and female health. In the ovarian follicle I identified a novel form of extracellular matrix (focimatrix) which develops in the ovary before the synthetic enzymes needed for sex steroids are present. Using evidence from other tissues, I developed ideas on how this matrix regulates the enzymes for hormone synthesis. I will examine a mechanism by which focimatrix could directly affect steroid hormone production.