text: The physiological role of HDL centers around the reverse cholesterol transport system.  Nascent HDL secreted into the plasma by the liver or intestine pick up free cholesterol from peripheral tissues and the arterial wall, an action mediated mainly by the ATP-binding cassette A1 (ABCA1).  The enzyme lecithin-cholesteryl acetyltransferase (LCAT) catalyzes the esterification of the free cholesterol, and also converts the nascent HDL into the mature form.  The esterified cholesterol is transported to the liver where cholesterylester transfer protein (CETP), an enzyme produced in the liver, acts on it transferring the cholesterol to other apo B containing lipoproteins.   The cholesterol-deplete HDL gets broken down by triglyceride lipases releasing apo A-I which either takes up free cholesterol to continue the cycle, or gets eliminated in the kidneys.  In addition to its atheroprotective against cardiovascular diseases, HDL also exhibits anti-oxidant, anti-inflammatory, anti-apoptotic, anti-coagulant, vasodilatory, and metabolic properties.
option_0: High density lipoprotein physiology
option_1: Very low density lipoprotein physiology
option_2: Low density lipoprotein physiology
option_3: High density lipoprotein epidemiology and demographics
option_4: Low density lipoprotein epidemiology and demographics
option_5: High density lipoprotein pathophysiology
option_6: Low density lipoprotein pathophysiology
option_7: Hyperlipoproteinemia epidemiology and demographics