From the Guidelines
Lipoproteins are the primary component of atherosclerotic plaques, specifically triglyceride-rich lipoproteins which can be taken up directly by macrophages, turning them into foam cells rich in indigestable cholesterol droplets. The development of atherosclerosis involves the accumulation of these lipoproteins in the arterial walls, leading to intimal low-grade inflammation through triglyceride hydrolysis and cholesterol accumulation in arterial wall foam cells 1. This process is supported by the finding that elevated levels of triglyceride-rich lipoproteins are causally associated with low-grade inflammation, as demonstrated by a Mendelian randomization design study of 60,608 individuals 1.
Key points to consider:
- Triglyceride-rich lipoproteins can be taken up directly by macrophages without modification, unlike LDL particles which need to be modified to be taken up by macrophages 1.
- The presence of foam cells in the intima is a source of local intimal inflammation, which contributes to the development of atherosclerosis 1.
- Elevated levels of remnant cholesterol and triglyceride-rich lipoproteins are associated with increased levels of C-reactive protein, a marker of inflammation 1.
- Controlling blood lipid levels is crucial in preventing and managing atherosclerosis, as lipoproteins are the primary component of atherosclerotic plaques.
In contrast, while foam cells, platelets, and red blood cells play a role in the development and progression of atherosclerosis, they are not the primary component of atherosclerotic plaques. Foam cells are a secondary component, formed when macrophages engulf oxidized lipoproteins, and platelets and red blood cells may become involved in the inflammatory process or become trapped in advanced plaques. However, the primary component of atherosclerotic plaques is lipoproteins, specifically triglyceride-rich lipoproteins.
From the Research
Atherosclerotic Plaque Composition
The primary component of an atherosclerotic plaque is a topic of interest in various studies. According to the available evidence:
- Foam cells are considered a hallmark of atherosclerotic lesions and are characterized by an aberrant accumulation of cytosolic lipid droplets 2.
- The formation of foam cells is a key process in the development of atherosclerotic plaques, and macrophages play a central role in this process 3, 4.
- Lipoproteins, such as low-density lipoprotein (LDL), also contribute to the formation of atherosclerotic plaques by depositing cholesterol in the arterial wall 5, 6.
- Other components, including inflammatory cells, growth factors, and hormones, can also affect the development and progression of atherosclerotic lesions 4, 5.
Key Components
The key components of an atherosclerotic plaque include:
- Foam cells, which are formed from macrophages and other cells that accumulate lipid droplets 3, 2.
- Lipoproteins, such as LDL, which deposit cholesterol in the arterial wall 5, 6.
- Inflammatory cells, such as monocytes, which contribute to the progression of atherosclerotic disease 5.
- Other factors, such as growth factors and hormones, which can affect the development and progression of atherosclerotic lesions 4.