The role of endothelial lipase in high density lipoprotein metabolism

动脉粥样硬化是澳大利亚死亡和残疾的主要原因。高水平的血液胆固醇会增加动脉粥样硬化的风险。这种风险的增加是由低密度脂蛋白（LDL）中携带的胆固醇引起的。然而，并非所有的胆固醇都是有害的。血液中有一部分胆固醇是由高密度脂蛋白（HDL）携带的，它是对抗动脉粥样硬化的有力保护剂。由于并不是所有的高密度脂蛋白都对动脉粥样硬化有同样的保护作用，所以了解血液中高密度脂蛋白的水平是如何调节的是很重要的。1999年，一种叫做内皮脂肪酶的新酶被发现。内皮脂肪酶显著降低小鼠体内高密度脂蛋白水平。发生这种情况的原因尚不清楚。这个项目的主要目的是弄清楚内皮脂肪酶是如何降低高密度脂蛋白水平的，以及它是平等地降低所有高密度脂蛋白水平，还是优先降低某些类型的高密度脂蛋白水平。该项目的结果将确定内皮脂肪酶如何影响高密度脂蛋白的能力，以防止人类动脉粥样硬化。

Atherosclerosis is a major cause of death and disability in Australia. A high level of blood cholesterol increases the risk of developing atherosclerosis. This increase in risk is caused by the cholesterol that is carried in low density lipoproteins (LDL). However, not all cholesterol is bad. A proportion of the cholesterol in blood is carried in high density lipoproteins (HDL), which are powerful protectors against atherosclerosis. As not all HDL protect equally well against atherosclerosis, it is important to know how blood levels of HDL are regulated. In 1999 a new enzyme called endothelial lipase was discovered. Endothelial lipase dramatically decreases HDL levels in mice. The reason why this happens is not known. The main aims of this project are to work out how endothelial lipase decreases HDL levels and whether it decreases the levels of all HDL equally or whether it preferentially decreases the levels of certain types of HDL. The outcome of this project will establish how endothelial lipase affects the ability of HDL to protect against atherosclerosis in humans.