Human carotid atherosclerotic lesion protein components decrease cholesterol biosynthesis rate in macrophages through
Elad Cohen1, Michael Aviram, Soliman Khatib
1Department of Oxidative Stress and Human Diseases, MIGAL-Galilee Research Institute, Kiryat Shmona, Tel Hai College, Israel; The Lipid Research Laboratory, the Technion Rappaport Faculty of Medicine and Research Institute, Rambam Health Care Campus, Technion- Israel Institute of Technology, Haifa, Israel.
Biofactors (Oxford, England)
|February 3, 2015
Summary
Human carotid plaque homogenate significantly reduces macrophage cholesterol synthesis by inhibiting HMGCoA Reductase. This finding offers a novel therapeutic target for delaying foam cell formation and atherosclerosis progression.
Area of Science:
- Cardiovascular Biology
- Atherosclerosis Research
- Cellular Metabolism
Background:
- Atherosclerosis involves cholesterol-laden macrophages forming foam cells, a key early event.
- Understanding interactions between arterial lesion components and blood cells is crucial.
Purpose of the Study:
- To investigate the impact of human carotid plaque homogenate on macrophage cholesterol biosynthesis.
- To identify the specific components within the plaque responsible for this effect.
Main Methods:
- Human carotid plaques were homogenized and applied to macrophage cultures.
- Cholesterol biosynthesis rates were measured using radiolabeled precursors.
- Key enzymes and gene expression (HMGCoA Reductase) were analyzed.
Main Results:
- Plaque homogenate dose-dependently inhibited macrophage cholesterol biosynthesis by up to 50%.
- Inhibition was linked to 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCoA Reductase) activity, not free cholesterol or lipoproteins.
- Lipoprotein-deficient homogenate retained inhibitory activity, implicating proteins and phospholipids.
Conclusions:
- Human carotid plaque components, particularly proteins and phospholipids, inhibit macrophage cholesterol biosynthesis via HMGCoA Reductase feedback.
- This mechanism may represent an endogenous anti-atherogenic effect, potentially delaying foam cell formation and disease progression.
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