plasma lipoprotein particle remodeling

Definition

Target type: biologicalprocess

The acquisition, loss or modification of a protein or lipid within a plasma lipoprotein particle, including the hydrolysis of triglyceride by hepatic lipase, with the subsequent loss of free fatty acid, and the esterification of cholesterol by phosphatidylcholine-sterol O-acyltransferase (lecithin cholesterol acyltransferase; LCAT). [GOC:BHF, GOC:expert_pt, GOC:mah, GOC:rl]

Plasma lipoprotein particle remodeling is a dynamic process essential for maintaining lipid homeostasis in the body. It involves the modification of the composition and structure of lipoprotein particles, specifically very low-density lipoproteins (VLDL) and low-density lipoproteins (LDL), to regulate the transport of lipids, such as cholesterol and triglycerides, throughout the circulation. The process is initiated in the liver, where VLDL particles are assembled and secreted. VLDL particles are rich in triglycerides and contain a core of cholesterol esters surrounded by a phospholipid monolayer. As VLDL particles circulate, they undergo a series of enzymatic modifications that lead to the formation of LDL particles. The first step in VLDL remodeling is the hydrolysis of triglycerides by lipoprotein lipase (LPL), an enzyme primarily found in adipose tissue and muscle. LPL removes triglycerides from VLDL, generating smaller, denser particles known as intermediate-density lipoproteins (IDL). These IDLs can be further metabolized by LPL or taken up by the liver. The second step in VLDL remodeling involves the transfer of cholesteryl esters from VLDL to HDL, a process facilitated by cholesteryl ester transfer protein (CETP). This transfer results in the enrichment of VLDL with cholesterol and the depletion of triglycerides, leading to the formation of LDL particles. LDL particles are smaller and denser than VLDL and are the primary carriers of cholesterol in the circulation. LDL particles can be taken up by cells through receptor-mediated endocytosis, allowing for the delivery of cholesterol to tissues. Alternatively, LDL particles can be oxidized, leading to the formation of oxidized LDL (oxLDL), which is pro-inflammatory and contributes to the development of atherosclerosis. In summary, plasma lipoprotein particle remodeling is a complex process that involves the sequential modification of lipoprotein particles, primarily VLDL and LDL, through the actions of enzymes like LPL and CETP. This process is crucial for maintaining lipid homeostasis, delivering cholesterol to tissues, and preventing the accumulation of harmful lipid species in the circulation.'
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Proteins (2)

Compounds (4)