Curcumin inhibits cellular cholesterol accumulation by regulating SREBP-1/caveolin-1 signaling pathway in vascular smooth muscle cells
Aim: To investigate the protective effect and the possible mechanism of curcumin on anti-atherosclerosis. Methods: Morphological changes of atherosclerotic lesions taken from apoE knockout (apoE^-/-) mice were determined by hematoxylineosin staining. Intracellular lipid droplets and lipid levels wer...
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Published in | Acta pharmacologica Sinica Vol. 29; no. 5; pp. 555 - 563 |
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Main Authors | , , , , , , , |
Format | Journal Article |
Language | English |
Published |
United States
Nature Publishing Group
01.05.2008
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Subjects | |
Online Access | Get full text |
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Summary: | Aim: To investigate the protective effect and the possible mechanism of curcumin on anti-atherosclerosis. Methods: Morphological changes of atherosclerotic lesions taken from apoE knockout (apoE^-/-) mice were determined by hematoxylineosin staining. Intracellular lipid droplets and lipid levels were assayed by oil red O staining and HPLC. The protein expression of caveolin- 1 was quantified by Western blotting. Translocation and the expression of sterol response element-binding protein-1 (SREBP-1) were indirectly detected by an immunofluorescence analysis. Results: The administration of 20 mg.kg^-1.d^-1 curcumin to apoE^-/- mice for 4 months induced a 50% reduction of atherosclerotic lesions and yielded a 5- fold increase in the caveolin-1 expression level as compared to the model group. Rat vascular smooth muscle cells (VSMC) pretreated with 50 mg.L^-1 ox-lipid density lipoprotein(ox-LDL) for 48 h increased cellular lipid contents, and stimulated SREBP-1 translocation, but decreased the caveolin-1 expression level. Lipid-loaded cells exposed to curcumin at various concentrations (12.5, 25, and 50 μmol.L^-1) for different durations (0, 6, 12, 24, and 48 h) significantly diminished the number and area of cellular lipid droplets, total cholesterol, cholesterol ester, and free choles- terol accompanying the elevation of the caveolin- 1 expression level (approximately 3-fold); the translocation of SREBP-1 from the cytoplasm to the nucleus was inhibited compared with the models. Lipid-loaded VSMC exposed to N-acetylLeu-Leu-norleucinal, a SREBP- 1 protease inhibitor, showed increased nuclear trans- location of SREBP-1, reduced caveolin-1 expression level, and upregulated cellu- lar lipid levels. Condusion: Curcumin inhibits ox-LDL-induced cholesterol accu- mulation in cultured VSMC through increasing the caveolin-1 expression via the inhibition of nuclear translocation of SREBP- 1. |
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Bibliography: | caveolin-1 curcumin; cholesterol accumulation; vascular smooth muscle cells; caveolin-1; sterol response element-binding protein-1 cholesterol accumulation sterol response element-binding protein-1 vascular smooth muscle cells curcumin 31-1347/R R329.2 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 1671-4083 1745-7254 |
DOI: | 10.1111/j.1745-7254.2008.00783.x |