High density lipoproteins and coronary heart disease

Area of Science:

• Cardiovascular Science
• Lipid Metabolism
• Atherosclerosis Research

Background:

• An established inverse relationship exists between high density lipoprotein (HDL) cholesterol concentration and coronary heart disease (CHD) development.
• The precise nature of this association in humans remains debated, with uncertainty whether HDL is protective or if low HDL is merely an epiphenomenon in CHD patients.

Purpose of the Study:

• To investigate the direct antiatherogenic potential of high density lipoproteins (HDLs).
• To explore the potential mechanisms underlying HDL-mediated protection against atherosclerosis.
• To examine whether specific HDL subpopulations confer differential protection against CHD.

Main Methods:

• Review of existing human epidemiological studies.
• Analysis of recent findings from transgenic mouse models investigating HDL function.
• Evaluation of circumstantial evidence regarding interventions to elevate HDL cholesterol.

Main Results:

• Transgenic mouse studies provide evidence that HDLs are directly antiatherogenic.
• Potential mechanisms for HDL protection include roles in plasma cholesterol transport and non-lipid transport functions.
• Studies suggest potential heterogeneity in cardioprotective abilities among HDL subpopulations.

Conclusions:

• HDLs likely play a direct role in preventing atherosclerosis.
• Further research is needed to elucidate the exact mechanisms of HDL's protective effects.
• While evidence is suggestive, dedicated human studies are required to confirm if increasing HDL cholesterol concentration reduces coronary risk.