重新认识高密度脂蛋白与动脉粥样硬化的关系

Re-understanding the relationship of high-density lipoprotein with atherosclerosis vascular disease

低密度脂蛋白（LDL）促进动脉粥样硬化形成及临床发展，高密度脂蛋白（HDL）则被广泛认为是动脉粥样硬化的保护性因素。因此，HDL胆固醇（HDL—C）通常被认为是“好的胆固醇”。然而，最新的研究认为事实可能并非如此，有必要对HDL—C的临床价值进行再评估。HDL的主要功能是动员肝脏组织外的胆固醇转移到肝脏分解代谢，其在胆固醇代谢中以及其他生物学作用都取决于HDL颗粒的数量及其蛋白质和脂质成分的含量，这些因素很难全部通过HDL—C的浓度来表示。如果HDL颗粒内成分发生病理性改变，它甚至会对血管产生不利影响。因此，血浆中高浓度的HDL—C并不总是保护性因素，一些以提高HDL—C浓度的药物临床研究的结论未能证实HDL—C浓度升高所预期的保护性作用。探索HDL和动脉粥样硬化性疾病二者间复杂的关系及机制，这对于HDL检测的临床应用具有指导意义。

While several lines of evidence prove that elevated concentrations of low-density lipoproteins （LDL） usually contribute to the development of atherosclerosis and its clinical consequences, high-density lipoproteins （HDL） are widely believed to exert atheroprotective effects. Hence, HDL cholesterol （HDL-C） is in general still considered as ＂good cholesterol＂. Recent researches, however, suggest that this might not always be the case and that a fundamental reassessment of the clinical significance of HDL-C is warranted. The main function of HDL is to transfer the cholesterol outside the liver into the liver for catabolism. The liver＇s cholesterol metabolism and other biological effects are dependent on the number of HDL particles and its proteins and lipid contents. These functions are difficult to be described simply with the HDL-C concentration. If the components of HDL particles change, they may have adverse effects on the blood vessels. Thus, high concentrations of HDL-C in plasma are not always protective factors, and some clinical trials improving HDL-C concentrations have failed to confirm a protective effect. To explore the complex relationship and pathological mechanism between HDL and atherosclerotic diseases, it is instructive for clinical application of the HDL measurement.