The mechanisms of high-density lipoprotein (HDL) and its role in preventing heart disease are explored in the March 2006 issue of Nature Clinical Practice Cardiovascular Medicine. Attention has focused on HDL because raised concentrations can help to prevent arterial damage, even in the presence of raised low-density lipoprotein (LDL) concentrations - a major risk factor for heart disease.
Anatol Kontush and M John Chapman explore the role of HDL, focusing on the small, dense form (HDL3), which is thought to have particularly potent effects against cardiovascular disease. Cardiovascular risk is raised in the presence of an imbalance in the types of lipids and lipoproteins circulating in the blood stream, termed dyslipidemia. Dyslipidemia results in an increase in cholesterol-rich apolipoproteins carrying LDL, (a transporter of cholesterol), which in turn can cause fatty deposits to form in blood vessel walls (atherogensis). These deposits can lead to atherosclerosis (hardening of the blood vessel walls), coronary artery disease, and stroke. HDL, on the other hand, encourages excretion of cholesterol from the body via the liver, but in dyslipidemic conditions, the structure of HLD3 particles is altered and its ability to transport cholesterol impaired. Dyslipidemia especially affects people with metabolic diseases, such as type 2 diabetes mellitus, or other metabolic syndromes, although it may be present in people without such disorders.
The authors conclude that it might be possible to capitalize on the potent effects of HDL3 to reduce the risk of cardiovascular disease. Therapy should be targeted not only at increasing the quantity of circulating particles, but also on improving the quality to counteract impairment in performance.
Anatol Kontush (National Institute for Health and Medical Research, Paris, France)
Rachel Ashton (Senior Editor, Nature Clinical Practice Cardiovascular Medicine)
Abstract available online.
(C) Nature Clinical Practice Cardiovascular Medicine press release.
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