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Updated: Jul 2, 2026
08:08
Two-photon Imaging of Intracellular Ca2+ Handling and Nitric Oxide Production in Endothelial and Smooth Muscle Cells of an Isolated Rat Aorta
Published on: June 10, 2015
[NADPH oxidase activity does not affect cellular cholesterol loading in vascular smooth muscle cells]
Zhong-Hua Yuan1, Nageswara R Madamanchi, Aleksandr E Vendrov
1Institute of Cardiovascular Disease, Key Laboratory for Arteriosclerology of Hunan Province, University of South China, Hengyang 421001, China.
Sheng Li Xue Bao : [Acta Physiologica Sinica]
|August 12, 2008
Summary
NADPH oxidase, crucial in atherosclerosis, does not influence vascular smooth muscle cell cholesterol metabolism or macrophage-like transformation. Deleting the p47phox gene in these cells did not alter cholesterol handling.
Area of Science:
- Cardiovascular Biology
- Cellular Metabolism
- Atherosclerosis Research
Background:
- Reactive oxygen species from NADPH oxidase impact vascular smooth muscle cell proliferation and migration, key in atherosclerosis.
- Understanding NADPH oxidase's role in cellular cholesterol metabolism is vital for atherosclerosis pathophysiology.
Purpose of the Study:
- To investigate the role of NADPH oxidase, specifically the p47phox subunit, in cellular cholesterol metabolism within vascular smooth muscle cells.
- To determine if p47phox deficiency affects the transformation of vascular smooth muscle cells into a macrophage-like state.
Main Methods:
- Utilized wild-type and p47phox knockout vascular smooth muscle cells.
- Cells were loaded with cholesterol and incubated with or without thrombin.
- Assessed foam cell formation, intracellular cholesterol accumulation, lipid droplet formation, and expression of key proteins (ABCA1, ACAT1, adipophilin) and inflammatory markers (MCP-1, VCAM-1).
Main Results:
- Cholesterol loading increased intracellular cholesterol and lipid droplets similarly in both wild-type and p47phox-deficient cells.
- Vascular smooth muscle cells showed decreased smooth muscle alpha-actin and increased Mac-2, indicating a macrophage-like state, irrespective of p47phox status.
- Expression of cholesterol metabolism proteins (ABCA1, ACAT1) and lipid droplet protein (adipophilin) increased similarly in both cell types.
- Inflammatory gene expression (MCP-1, VCAM-1) showed no significant changes related to p47phox deficiency.
Conclusions:
- p47phox-dependent NADPH oxidase is not involved in the transdifferentiation of vascular smooth muscle cells into a macrophage-like phenotype following cholesterol loading.
- Deletion of the p47phox gene does not affect cellular cholesterol metabolism in vascular smooth muscle cells.
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