The Role of Androgens in Angiogenesis and Endothelial Progenitor Cell Mobilisation

男性性激素在调节新血管生长中的作用目的本项目旨在研究男性性激素（雄激素）在以下方面的作用：1）调节新血管生长2）动员骨髓细胞，帮助血管修复和生长。越来越多的证据表明，心脏和血管能够自我修复以应对疾病。例如，当冠状动脉由于疾病而变得严重狭窄时，身体可以通过在称为血管生成的过程中制造新血管来部分补偿。最近，已经发现在血流中循环的细胞具有辅助血管生成和血管修复的能力。这些来自骨髓的细胞被称为内皮祖细胞。因此，内皮祖细胞是心血管系统自我修复和维持能力的重要组成部分。虽然男性比女性更容易患上冠状动脉疾病，但与女性相比，男性在心脏病发作后也更有可能获得良好的结果。心脏病发作后的性别差异表明，性激素如雄激素可能在心脏病发作后的修复反应中发挥作用。事实上，在细胞和动物中的一些研究中有证据表明雄激素会增加血管形成。研究我们将研究雄激素对血管生成的影响，并使用人类细胞，动物研究和人类临床试验中动员内皮祖细胞。意义这项研究将帮助我们进一步了解男性和女性在心脏病方面的差异。这也将帮助我们更多地了解老年男性雄激素替代的风险-益处。

The Role of Male Sex Hormones in Regulating New Blood Vessel Growth AIMS This proposed project seeks to investigate the role that male sex hormones (androgens) play in: 1) Regulating new blood vessel growth 2) Mobilising cells from the bone marrow which assist in blood vessel repair and growth. BACKGROUND Increasing evidence indicates that the heart and blood vessels are able to repair themselves in response to disease. For example, when a coronary artery becomes severely narrow as a result of disease, the body can partially compensate by making new blood vessels in a process termed angiogenesis. Recently, cells circulating in the blood stream have been found to have the ability to assist in angiogenesis and in blood vessel repair. These cells, which come from the bone marrow, are called endothelial progenitor cells. Endothelial progenitor cells are therefore an important part of the cardiovascular system's ability to repair and maintain itself. While men are more likely to develop coronary artery disease than women, men are also more likely to have a favourable outcome after a heart attack compared to women. This gender difference after heart attacks, suggests that sex hormones such as the androgens, may play a role in the reparative response after a heart attack. In fact, there is evidence from some studies in cells and in animals that androgens increase blood vessel formation. RESEARCH PLAN We will study the effects of androgens on angiogenesis and in mobilising endothelial progenitor cells using human cells, animal studies and in a human clinical trial SIGNIFICANCE This research will help us further understand the differences between men and women in heart disease. It will also help us understand more about the risks-benefits of androgen replacement in older men.