OxLDL

Low-density lipoprotein (LDL) plays a principal role in oxidative stress due to its oxidative modification to oxidized LDL (oxLDL). The oxidation of LDL is a complex process during which both the protein and the lipids undergo oxidative changes and form complex products. Formed oxLDL induces inflammatory reactions within the arterial wall, which are implicated in all phases of the atherosclerotic plaque development. It may contain a specific oxidation product and it may also contain limited amounts of a variety of degraded oxidized lipid products.

OxLDL induces the expression of several cell surface adhesion molecules to activate endothelial cells (ECs). These molecules mediate the rolling and adhesion of blood leukocytes (monocytes and T cells). In that process, heat shock protein 60 (HSP60) and HSP90 may play a central role as antigens. OxLDL function through binding to several SRs, including SR-A, SR-BI, CD36, and lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1).

OxLDL is involved in all stages of atherosclerosis from the initiation of fatty streaks to the development of plaque instability and rupture. It is potentially associated with coronary heart disease (CHD). It downregulates endothelial nitric oxide synthase, increases the formation of metalloproteinases, and induces apoptosis in human coronary endothelial cells.