Update on the pathogenesis of atherosclerosis

Area of Science:

• Cardiovascular Biology
• Pathogenesis of Atherosclerosis

Background:

• Atherosclerotic plaque comprises deposited lipids, primarily cholesteryl esters and cholesterol from lower-density lipoproteins (LDL, VLDL), and proliferated smooth muscle cells.
• Lipid deposition often precedes smooth muscle cell buildup in artery walls, contributing to plaque formation.
• Research in the 1980s identified various LDL and VLDL forms (e.g., LDL-1, beta-VLDL, Lp(a)) influencing atherosclerosis, alongside endothelial function alterations impacting lipoprotein transport.

Purpose of the Study:

• To review recent advancements in understanding atherosclerosis pathogenesis.
• To highlight the role of specific lipoprotein subclasses and cellular signaling in plaque development.
• To explore the impact of oxidized LDL, antioxidants, and immune complexes on atherogenesis.

Main Methods:

• Review of scientific literature focusing on lipid metabolism, lipoprotein analysis, endothelial function, and cellular proliferation in atherosclerosis.
• Analysis of studies investigating the effects of oxidized LDL and antioxidants on lesion development.
• Examination of research on immune complexes and their association with accelerated atherogenesis.

Main Results:

• Specific LDL and VLDL subclasses are linked to accelerated atherosclerosis and are influenced by diet.
• Platelet-derived growth factor (PDGF) and leukotrienes are implicated in smooth muscle cell proliferation, potentially stimulated by LDL.
• Oxidized LDL and its apolipoprotein B are involved in atherogenesis, with antioxidants showing a suppressive effect.
• Circulating immune complexes accelerate atherogenesis, even without classic risk factors, leading to a distinct form termed 'atheroarteritis'.

Conclusions:

• Atherosclerosis pathogenesis is complex, involving lipid accumulation, smooth muscle cell proliferation, and inflammatory responses.
• Oxidized LDL presents a significant pathway in atherogenesis, responsive to antioxidant intervention.
• Immune complex-mediated processes represent an alternative pathway for accelerated atherosclerosis, highlighting the role of the immune system.