Test Details
Oxidized Low Density Lipoprotein (OxLDL)
Oxidized Low Density Lipoprotein is considered to be an important independent driving factor of atherosclerosis. OxLDL is readily taken up by macrophages and is converted to cholesterol-rich foam cells, leading in turn to the fatty streaks and lipid-rich plaques, which are the hallmark of atherosclerosis.
Methodology
Immunoturbidimetric assay.
Patient Preparation
8-12 hour fast prior to collection is recommended. Patient may drink water, black coffee or tea only (no dairy or sugar).
Preferred Specimen
1.0 mL serum (0.5 mL minimum) collected in serum separator tube (SST/Tiger Top).
Alternate Specimen
1.0 mL EDTA plasma (0.5 mL minimum) collected in plasma separator tube (Pearl Top)
Transport Temperature
Refrigerated (ship on frozen cold packs)
Stability
7 days at room temperature
Lab Values
Oxidized Low Density Lipoprotein (OxLDL)
- Optimal: <1.30 mg/dL
- Borderline: 1.30-1.60 mg/dL
- Increased Risk: >1.60 mg/dL
Clinical Significance
Oxidized Low Density Lipoprotein (OxLDL)
It has long been known that atherogenic lipoproteins, especially LDL must be modified or oxidized prior to being taken up by scavenger receptors on the surface of macrophages in the artery wall. During this process LDL, especially small dense LDL, crosses the endothelial cell layer and may react in the neointimal space with glycosaminoglycans (GAG) resulting in the modification or oxidation of lysine residues within apolipoprotein B-100 (apoB) on the surface of LDL, resulting in the formation of OxLDL. OxLDL is then readily taken up by macrophages which are then converted to cholesterol-rich foam cells, leading in turn to the fatty streaks and lipid-rich plaques, which are the hallmark of atherosclerosis. As the process continues there is in-migration of vascular smooth muscle cells (VSMC), cell proliferation, calcification, and clot formation. This process over time leads to the narrowing, obstruction or complete occlusion of arteries supplying the heart, the brain, and other vital tissues, leading to atherosclerotic cardiovascular disease (ASCVD). ASCVD is the cause of heart attacks, strokes, and peripheral disease, and is the leading cause of death and disability in our society. It has clearly been documented that increased levels of oxidized LDL with this detection method is associated with metabolic syndrome and increased ASCVD risk.1-4 1-4
References
1. Holvoet P et al. Association between circulating oxidized low-density lipoprotein and incidence of the metabolic syndrome. JAMA. 2008; 299: 2287-2293.
2. Holvoet P et al. Circulating oxidized LDL is a useful marker for identifying patients with coronary artery disease. Arterioscler Thromb Vasc Biol. 2001; 21: 844-848.
3. Nishi K et al. Oxidized LDL in carotid plaques and plasma associates with plaque instability. Arterioscler Thromb Vasc Biol. 2002; 22: 1649-1654.
4. Meisinger C et al. Plasma oxidized low-density lipoprotein, a strong predictor for acute coronary heart disease events in apparently healthy, middle-aged men from the general population. Circulation 2005; 112: 651-657.
Treatment Options
Oxidized Low Density Lipoprotein (OxLDL)
- Consider lifestyle modifications such as diet and exercise for weight reduction if
appropriate. Studies show a decrease in oxLDL levels after six months of lifestyle
modification.1 - If direct LDL-C levels are not optimal, consider lipid-lowering therapies.2
- If OxLDL levels are high, consider the use of natural vitamin E supplementation at 400 units per day.3
References
1. Srimahachota, Suphot et al. Effects of lifestyle modification on oxidized LDL, reactive oxygen species production and endothelial cell viability in patients with coronary artery disease. Clinical biochemistry, 2010; 43(10-11):858-62.
2. 2. Grundy SM, Stone NJ, Bailey AL, et al. 2018 AHA/ACC/AACVPR/AAPA/ABC/ACPM/ADA/ADA/APHA/ASPC/NLA/PCNA Guideline on the management of blood cholesterol: A report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation. 2019;139:e1082-e1143.
3. Zhang, Shengyu et al. Natural products: The role and mechanism in low-density lipoprotein oxidation and atherosclerosis.Phytother Res. 2021;35(6):2945-2967.
