High-density lipoprotein: key molecule in cholesterol efflux and the prevention of atherosclerosis

Area of Science:

• Cardiovascular Biology
• Lipid Metabolism
• Atherosclerosis Research

Background:

• Macrophage cholesterol accumulation and foam cell formation are central to atherosclerosis initiation.
• Maintaining cholesterol homeostasis in macrophages is crucial for preventing foam cell formation.
• Epidemiological studies link lower high-density lipoprotein (HDL) cholesterol levels to increased atherosclerosis risk.

Purpose of the Study:

• To review current knowledge on HDL's role in cholesterol homeostasis and atherosclerosis.
• To summarize the biological activities of HDL-associated components in reverse cholesterol transport (RCT).
• To discuss HDL's atheroprotective mechanisms beyond RCT, including antioxidant and anti-inflammatory properties.

Main Methods:

• Literature review of studies on HDL function and atherosclerosis.
• Analysis of apolipoproteins, enzymes, lipid transfer proteins, receptors, and transporters involved in HDL.
• Examination of molecular mechanisms underlying HDL's atheroprotective effects.

Main Results:

• HDL plays a critical role in reverse cholesterol transport (RCT), moving cholesterol from peripheral tissues to the liver for excretion.
• HDL-associated components like apolipoproteins, enzymes, and transporters are key players in RCT.
• HDL exhibits atheroprotective functions beyond RCT, including antioxidant, anti-thrombotic, anti-inflammatory, and anti-apoptotic properties.

Conclusions:

• HDL is essential for maintaining cholesterol homeostasis in macrophages, preventing foam cell formation and thus atherosclerosis.
• HDL-mediated RCT is a primary mechanism for HDL's protective effect against atherosclerosis.
• HDL possesses multiple atheroprotective properties that contribute to cardiovascular health.