High-density lipoprotein heterogeneity and function in reverse cholesterol transport.

Area of Science:

• Cardiovascular Science
• Lipid Metabolism
• Atherosclerosis Research

Background:

• High-density lipoprotein (HDL) is recognized for its cardioprotective role, primarily through mediating reverse cholesterol transport (RCT).
• The antiatherogenic potential of HDL is influenced by both its concentration and its biological quality.
• Understanding HDL subspecies is key to comprehending its overall function in RCT.

Purpose of the Study:

• To review the current understanding of how individual HDL particle subclasses contribute to HDL performance in RCT.
• To explore the relationship between HDL subspecies functionality and antiatherogenic effects.
• To highlight the importance of HDL quality over quantity in cardiovascular health.

Main Methods:

• Review of recent research on HDL heterogeneity and its impact on RCT.
• Examination of RCT mechanisms in macrophages, including key plasma and cell factors.
• Analysis of studies manipulating factors involved in RCT and their effects on atherosclerosis.

Main Results:

• Nascent HDL particles containing apolipoprotein A-I are heterogeneous, with varying effects on the RCT pathway.
• Key factors influencing RCT include lecithin-cholesterol acyltransferase, cholesterol ester transfer protein, and ATP-binding cassette transporters.
• Plasma HDL levels do not reliably predict RCT extent; HDL cholesterol or apolipoprotein A-I levels may not correlate with cholesterol efflux from macrophages.

Conclusions:

• The antiatherogenic quality of HDL is determined by the functionality of its subspecies.
• The rate of cholesterol movement within the RCT pathway is critical.
• The specific contributions of different HDL particle types to RCT are being increasingly defined.