Even though atherosclerosis is primarily a chronic inflammatory process, lipids are involved in atherosclerotic plaque formation. Lipoproteins are components of the foam cells that eventually develop into the plaque if inflammation in blood vessels continues.
The body needs fat-soluble molecules. Since blood is an aqueous solution, there needs to be a way to get non-water-soluble fats distributed throughout the body. Lipoproteins fulfill this need. They are designed to allow fat-soluble, hydrophobic molecules to transport through aqueous blood. Lipoproteins contain a phospholipid membrane with protein receptors, but they are not cells. They are simple 'particles' that are filled with hydrophobic cargo (cholesterol and triglycerides).
There are four major lipoproteins:
- High-density lipoprotein (HDL)
- Low-density lipoprotein (LDL)
- Very-low density lipoprotein (VLDL)
- Chylomicrons (CM)
