Lipoproteins as biosensors of endothelial oxidative status

Abstract

Plasma lipoproteins are responsible for the transport and delivery of lipids throughout the body. Triglyceride-rich lipoproteins come into close contact with the arterial wall as they interact with lipoprotein lipase to unload triglycerides for storage in various tissues. We hypothesize that the attachment of plasma lipoproteins to the arterial wall facilitates the seeding of lipoproteins by reactive oxygen species that would be generated if the endothelium is damaged or inflamed. In other words, plasma lipoproteins serve as natural biosensors of the oxidative status of the endothelium. These triglyceride-rich lipoproteins are, however, rapidly converted to the cholesterol-rich LDL and are affected by a number of pro-oxidant and antioxidant processes present in the plasma. By assessing the oxidative susceptibility of plasma LDL, it is possible to derive a stable indicator of lipoprotein-associated oxidative stress, which could be used as an early sign of inflamed endothelium.

Key Words:

• lipoprotein
• oxidation hypothesis
• oxidative susceptibility
• oxidized LDL