Dissecting Associations Of Estradiol And Testosterone With Cardiovascular Outcomes.
Funder
National Health and Medical Research Council
Funding Amount
$435,082.00
Summary
Controversy persists over whether falling testosterone (T) levels in ageing men increase risk of cardiovascular disease (CVD). T is converted by the enzyme aromatase into estradiol (E2). We will assess whether men with abnormal E2 levels are at risk of CVD, more so than men with low T. We will assess whether differences in the aromatase gene which alter E2 levels also influence the risk of CVD. The results will clarify the importance of hormones to CVD and guide new approaches to its treatment.
Functional Effects Of Polymorphic Variation Of The Aromatase (CYP19) Gene On Enzyme Activity:relationship To Disease
Funder
National Health and Medical Research Council
Funding Amount
$237,708.00
Summary
After menopause, oestrogen synthesis changes from an ovarian to an adipose source by concersion of androgens to estrogens, a process catalyzed by aromatase, the product of the CYP19 gene. We will generate mutants of the CYP19 gene that we have previously found in humans by site-directed mutagenesis and observe the effects of these mutants on aromatase function. This research will help with diagnosis and treatment of breast and other cancers and osteoporosis in humans .
The Regulation Of Aromatase In The Context Of Obesity And Postmenopausal Breast Cancer.
Funder
National Health and Medical Research Council
Funding Amount
$436,601.00
Summary
Current hormone therapy for breast cancer using inhibitors of oestrogen formation results in serious side-effects including bone loss, joint pain and possibly cognitive issues. Our current work is aimed at understanding how oestrogen formation is regulated with the goal of developing breast-specific inhibitors of oestrogen formation to obviate these problems. In addition, this work is aimed at devising therapeutic intervention to break the linkage between obesity and breast cancer.
Randomised Phase II Trial Of Neoadjuvant Chemotherapy +/- Concurrent Aromatase Inhibitor Endocrine Therapy To Down-stage Large Oestrogen Receptor Positive Breast Cancer
Funder
National Health and Medical Research Council
Funding Amount
$2,302,496.00
Summary
Women diagnosed with large oestrogen receptor positive breast cancer are often treated with chemotherapy before surgery to reduce the size of the cancer, while treatment to lower oestrogen levels is given after surgery. This trial is studying if combining chemotherapy with oestrogen lowering treatment before surgery will better shrink the cancer which can improve the surgery options.
Lipid Metabolism In The Aromatase Knock-out Mouse (ArKO)
Funder
National Health and Medical Research Council
Funding Amount
$408,055.00
Summary
Studies of humans with natural mutations in aromatase, the enzyme responsible for oestrogen biosynthesis, have revealed a number of unexpected roles for oestrogens in both males and females. These discoveries even challenge the definitions of oestrogens and androgens as we now know them. We have created a mouse model of oestrogen insufficiency by targetted disruption of the aromatase gene. These mice display a number of age dependent phenotypes including both male and female infertility, undermi ....Studies of humans with natural mutations in aromatase, the enzyme responsible for oestrogen biosynthesis, have revealed a number of unexpected roles for oestrogens in both males and females. These discoveries even challenge the definitions of oestrogens and androgens as we now know them. We have created a mouse model of oestrogen insufficiency by targetted disruption of the aromatase gene. These mice display a number of age dependent phenotypes including both male and female infertility, undermineralisation of the bones, intra-abdominal obesity, hypercholesterolaemia and insulin resistance. We are addressing the mechanisms of all of those phenotypes but in the present application we focus on the abnormalities in lipid metabolism. Thus we will seek to understand the increase in adiposity by examining the role of oestrogen in lipid synthesis, oxidation and breakdown in adipose tissue from intra-abdominal sites. We will also examine the role that oestrogen plays in cholesterol uptake, synthesis and catabolism by the liver as well as fatty acid synthesis and oxidation by the liver. These studies will be correlated with whole body parameters such as feeding behaviour, physical activity, energy expenditure, glucose and fat oxidation rates. We will also examine the effect of feeding a high cholesterol or a high fat diet on lipid metabolism in the oestrogen deficient animals, and we will determine the effect of oestradiol and isoflavone replacement on the phenotype. In this way we aim to reach a better understanding of the multiplicity of roles that oestrogens play in the regulation of lipid and cholesterol metabolism in both males and females. The results of such studies will be the development of better strategies to deal with pathologies resulting from disturbances in cholesterol and lipid metabolism.Read moreRead less