Abstract | BACKGROUND: METHODS AND RESULTS: We established a novel atherosclerosis-susceptible mouse model with both severe HHcy and hypercholesterolemia in which the mouse cystathionine beta-synthase (CBS) and apolipoprotein E ( apoE) genes are deficient and an inducible human CBS transgene is introduced to circumvent the neonatal lethality of the CBS deficiency (Tg-hCBS apoE(-/-) Cbs(-/-) mice). Severe HHcy accelerated atherosclerosis and inflammatory monocyte/macrophage accumulation in lesions and increased plasma tumor necrosis factor-alpha and monocyte chemoattractant protein-1 levels in Tg-hCBS apoE(-/-) Cbs(-/-) mice fed a high-fat diet. Furthermore, we characterized monocyte heterogeneity in Tg-hCBS apoE(-/-) Cbs(-/-) mice and another severe HHcy mouse model (Tg-S466L Cbs(-/-)) with a disease-relevant mutation (Tg-S466L) that lacks hyperlipidemia. HHcy increased monocyte population and selective expansion of inflammatory Ly-6C(hi) and Ly-6C(mid) monocyte subsets in blood, spleen, and bone marrow of Tg-S466L Cbs(-/-) and Tg-hCBS apoE(-/-) Cbs(-/-) mice. These changes were exacerbated in Tg-S466L Cbs(-/-) mice with aging. Addition of l- homocysteine (100 to 500 micromol/L), but not l-cysteine, maintained the Ly-6C(hi) subset and induced the Ly-6C(mid) subset in cultured mouse primary splenocytes. Homocysteine-induced differentiation of the Ly-6C(mid) subset was prevented by catalase plus superoxide dismutase and the NAD(P)H oxidase inhibitor apocynin. CONCLUSIONS: HHcy promotes differentiation of inflammatory monocyte subsets and their accumulation in atherosclerotic lesions via NAD(P)H oxidase-mediated oxidant stress.
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Authors | Daqing Zhang, Xiaohua Jiang, Pu Fang, Yan Yan, Jian Song, Sapna Gupta, Andrew I Schafer, William Durante, Warren D Kruger, Xiaofeng Yang, Hong Wang |
Journal | Circulation
(Circulation)
Vol. 120
Issue 19
Pg. 1893-902
(Nov 10 2009)
ISSN: 1524-4539 [Electronic] United States |
PMID | 19858416
(Publication Type: Journal Article, Research Support, N.I.H., Extramural)
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Chemical References |
- Apolipoproteins E
- Ccl2 protein, mouse
- Chemokine CCL2
- Tumor Necrosis Factor-alpha
- Cystathionine beta-Synthase
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Topics |
- Animals
- Apolipoproteins E
(genetics)
- Atherosclerosis
(immunology, metabolism, pathology)
- Body Weight
- Cells, Cultured
- Chemokine CCL2
(blood)
- Cystathionine beta-Synthase
(genetics, metabolism)
- Disease Models, Animal
- Female
- Homocystinuria
(immunology, metabolism, pathology)
- Humans
- Hyperhomocysteinemia
(immunology, metabolism, pathology)
- Macrophages
(immunology, pathology)
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Monocytes
(immunology, pathology)
- Oxidative Stress
(physiology)
- Pregnancy
- Severity of Illness Index
- Spleen
(cytology)
- Tumor Necrosis Factor-alpha
(blood)
- Vasculitis
(immunology, metabolism, pathology)
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