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Mackay CDA, Meechem MB, Patel VB. Macrophages in vascular disease: Roles of mitochondria and metabolic mechanisms. Vascul Pharmacol 2024:107419. [PMID: 39181483 DOI: 10.1016/j.vph.2024.107419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2024] [Revised: 08/16/2024] [Accepted: 08/21/2024] [Indexed: 08/27/2024]
Abstract
Macrophages are a dynamic cell type of the immune system implicated in the pathophysiology of vascular diseases and are a major contributor to pathological inflammation. Excessive macrophage accumulation, activation, and polarization is observed in aortic aneurysm (AA), atherosclerosis, and pulmonary arterial hypertension. In general, macrophages become activated and polarized to a pro-inflammatory phenotype, which dramatically changes cell behavior to become pro-inflammatory and infiltrative. These cell types become cumbersome and fail to be cleared by normal mechanisms such as autophagy. The result is a hyper-inflammatory environment causing the recruitment of adjacent cells and circulating immune cells to further augment the inflammatory response. In AA, this leads to excessive ECM degradation and chemokine secretion, ultimately causing macrophages to dominate the immune cell landscape in the aortic wall. In atherosclerosis, monocytes are recruited to the vascular wall, where they polarize to the pro-inflammatory phenotype and induce inflammatory pathway activation. This leads to the development of foam cells, which significantly contribute to neointima and necrotic core formation in atherosclerotic plaques. Pro-inflammatory macrophages, which affect other vascular diseases, present with fragmented mitochondria and corresponding metabolic dysfunction. Targeting macrophage mitochondrial dynamics has proved to be an exciting potential therapeutic approach to combat vascular disease. This review will summarize mitochondrial and metabolic mechanisms of macrophage activation, polarization, and accumulation in vascular diseases.
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Affiliation(s)
- Cameron D A Mackay
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Megan B Meechem
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada
| | - Vaibhav B Patel
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; Libin Cardiovascular Institute, University of Calgary, Calgary, Alberta, Canada.
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Ldlr-Deficient Mice with an Atherosclerosis-Resistant Background Develop Severe Hyperglycemia and Type 2 Diabetes on a Western-Type Diet. Biomedicines 2022; 10:biomedicines10061429. [PMID: 35740449 PMCID: PMC9220196 DOI: 10.3390/biomedicines10061429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/12/2022] [Accepted: 06/14/2022] [Indexed: 01/10/2023] Open
Abstract
Apoe-/- and Ldlr-/- mice are two animal models extensively used for atherosclerosis research. We previously reported that Apoe-/- mice on certain genetic backgrounds, including C3H/HeJ (C3H), develop type 2 diabetes when fed a Western diet. We sought to characterize diabetes-related traits in C3H-Ldlr-/- mice through comparing with C3H-Apoe-/- mice. On a chow diet, Ldlr-/- mice had lower plasma total and non-HDL cholesterol levels but higher HDL levels than Apoe-/- mice. Fasting plasma glucose was much lower in Ldlr-/- than Apoe-/- mice (male: 122.5 ± 5.9 vs. 229.4 ± 17.5 mg/dL; female: 144.1 ± 12.4 vs. 232.7 ± 6.4 mg/dL). When fed a Western diet, Ldlr-/- and Apoe-/- mice developed severe hypercholesterolemia and also hyperglycemia with fasting plasma glucose levels exceeding 250 mg/dL. Both knockouts had similar non-HDL cholesterol and triglyceride levels, and their fasting glucose levels were also similar. Male Ldlr-/- mice exhibited greater glucose tolerance and insulin sensitivity compared to their Apoe-/- counterpart. Female mice showed similar glucose tolerance and insulin sensitivity though Ldlr-/- mice had higher non-fasting glucose levels. Male Ldlr-/- and Apoe-/- mice developed moderate obesity on the Western diet, but female mice did not. These results indicate that the Western diet and ensuing hyperlipidemia lead to the development of type 2 diabetes, irrespective of underlying genetic causes.
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Grainger AT, Pilar N, Li J, Chen MH, Abramson AM, Becker-Pauly C, Shi W. Identification of Mep1a as a susceptibility gene for atherosclerosis in mice. Genetics 2021; 219:6377788. [PMID: 34849841 DOI: 10.1093/genetics/iyab160] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 09/10/2021] [Indexed: 12/21/2022] Open
Abstract
Atherosclerosis is the underlying cause of heart attack, ischemic stroke and peripheral arterial disease, and genetic factors involved remain mostly unidentified. We previously identified a significant locus on mouse chromosome 17 for atherosclerosis, Ath49, in an intercross between BALB/c and SM strains. Ath49 partially overlaps in the confidence interval with Ath22 mapped in an AKR × DBA/2 intercross. Bioinformatics analysis prioritized Mep1a, encoding meprin 1α metalloendopeptidase, as a likely candidate gene for Ath49. To prove causality, Mep1a-/-Apoe-/- mice were generated and compared with Mep1a+/+Apoe-/- mice for atherosclerosis development. Mep1a was found abundantly expressed in atherosclerotic lesions but not in healthy aorta and liver of mice. Mep1a-/- Apoe-/- mice exhibited significant reductions in both early and advanced lesion sizes. Loss of Mep1a led to decreased necrosis but increased macrophage and neutrophil contents in advanced lesions, reduced plasma levels of CXCL5 and an oxidative stress biomarker. In addition, Mep1a-/- mice had significantly reduced triglyceride levels on a chow diet. Thus, Mep1a is a susceptibility gene for atherosclerosis and aggravates atherosclerosis partially through action on oxidative stress and inflammation.
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Affiliation(s)
- Andrew T Grainger
- Departments of Biochemistry & Molecular Genetics, University of Virginia, Charlottesville, VA 22908, USA.,Radiology & Medical Imaging, University of Virginia, Charlottesville, VA 22908, USA
| | - Nathanael Pilar
- Radiology & Medical Imaging, University of Virginia, Charlottesville, VA 22908, USA
| | - Jun Li
- Radiology & Medical Imaging, University of Virginia, Charlottesville, VA 22908, USA
| | - Mei-Hua Chen
- Radiology & Medical Imaging, University of Virginia, Charlottesville, VA 22908, USA
| | - Ashley M Abramson
- Radiology & Medical Imaging, University of Virginia, Charlottesville, VA 22908, USA
| | | | - Weibin Shi
- Departments of Biochemistry & Molecular Genetics, University of Virginia, Charlottesville, VA 22908, USA.,Radiology & Medical Imaging, University of Virginia, Charlottesville, VA 22908, USA
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Macrophage-targeted, enzyme-triggered fluorescence switch-on system for detection of embolism-vulnerable atherosclerotic plaques. J Control Release 2019; 302:105-115. [DOI: 10.1016/j.jconrel.2019.03.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/08/2019] [Accepted: 03/27/2019] [Indexed: 01/21/2023]
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Cochain C, Vafadarnejad E, Arampatzi P, Pelisek J, Winkels H, Ley K, Wolf D, Saliba AE, Zernecke A. Single-Cell RNA-Seq Reveals the Transcriptional Landscape and Heterogeneity of Aortic Macrophages in Murine Atherosclerosis. Circ Res 2018; 122:1661-1674. [PMID: 29545365 DOI: 10.1161/circresaha.117.312509] [Citation(s) in RCA: 531] [Impact Index Per Article: 88.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 02/16/2018] [Accepted: 03/14/2018] [Indexed: 02/05/2023]
Abstract
RATIONALE It is assumed that atherosclerotic arteries contain several macrophage subsets endowed with specific functions. The precise identity of these subsets is poorly characterized as they have been defined by the expression of a restricted number of markers. OBJECTIVE We have applied single-cell RNA sequencing as an unbiased profiling strategy to interrogate and classify aortic macrophage heterogeneity at the single-cell level in atherosclerosis. METHOD AND RESULTS We performed single-cell RNA sequencing of total aortic CD45+ cells extracted from the nondiseased (chow fed) and atherosclerotic (11 weeks of high-fat diet) aorta of low-density lipoprotein receptor-deficient (Ldlr-/-) mice. Unsupervised clustering singled out 13 distinct aortic cell clusters. Among the myeloid cell populations, resident-like macrophages with a gene expression profile similar to aortic resident macrophages were found in healthy and diseased aortas, whereas monocytes, monocyte-derived dendritic cells, and 2 populations of macrophages were almost exclusively detectable in atherosclerotic aortas, comprising inflammatory macrophages showing enrichment in Il1b and previously undescribed TREM2hi (triggered receptor expressed on myeloid cells 2) macrophages showing enrichment in Trem2. Differential gene expression and gene ontology enrichment analyses revealed specific gene expression patterns distinguishing these 3 macrophage subsets and monocyte-derived dendritic cells and uncovered putative functions of each cell type. Notably, TREM2hi macrophages seemed to be endowed with specialized functions in lipid metabolism and catabolism and presented a gene expression signature reminiscent of osteoclasts, suggesting a role in lesion calcification. TREM2 expression was moreover detected in human lesional macrophages. Importantly, these macrophage populations were present also in advanced atherosclerosis and in Apoe-/- aortas, indicating relevance of our findings in different stages of atherosclerosis and mouse models. CONCLUSIONS These data unprecedentedly uncovered the transcriptional landscape and phenotypic heterogeneity of aortic macrophages and monocyte-derived dendritic cells in atherosclerotic and identified previously unrecognized macrophage populations and their gene expression signature, suggesting specialized functions. Our findings will open up novel opportunities to explore distinct myeloid cell populations and their functions in atherosclerosis.
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Affiliation(s)
- Clément Cochain
- From the Institute of Experimental Biomedicine (C.C., A.Z.).,University Hospital Würzburg, Germany; Comprehensive Heart Failure Center, Würzburg, Germany (C.C.)
| | - Ehsan Vafadarnejad
- Helmholtz Institute for RNA-based Infection Research, Würzburg, Germany (E.V., A.-E.S.)
| | | | - Jaroslav Pelisek
- Department of Vascular and Endovascular Surgery, Klinikum rechts der Isar, Technische Universität München, Munich, Germany (J.P.)
| | - Holger Winkels
- La Jolla Institute for Allergy and Immunology, CA (H.W., K.L., D.W.)
| | - Klaus Ley
- La Jolla Institute for Allergy and Immunology, CA (H.W., K.L., D.W.)
| | - Dennis Wolf
- La Jolla Institute for Allergy and Immunology, CA (H.W., K.L., D.W.).,Department of Cardiology and Angiology I, Faculty of Medicine, University Heart Center, University of Freiburg, Germany (D.W.)
| | | | - Alma Zernecke
- From the Institute of Experimental Biomedicine (C.C., A.Z.)
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Ou L, Li X, Chen B, Ge Z, Zhang J, Zhang Y, Cai G, Li Z, Wang P, Dong W. Recombinant Human Cytoglobin Prevents Atherosclerosis by Regulating Lipid Metabolism and Oxidative Stress. J Cardiovasc Pharmacol Ther 2017; 23:162-173. [PMID: 28954528 DOI: 10.1177/1074248417724870] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Lingling Ou
- The First Affiliated Hospital of Jinan University, Guangzhou, China
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Xin Li
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
- Department of Medical Research, General Hospital of Guangzhou Military Command of PLA, Guangzhou, China
| | - Baihong Chen
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Zhenhuang Ge
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Junyi Zhang
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Ye Zhang
- The First Affiliated Hospital of Jinan University, Guangzhou, China
| | - Gaotai Cai
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Zhen Li
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Ping Wang
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
| | - Wenqi Dong
- School of Laboratory Medicine and Biotechnology, Southern Medical University, Guangzhou, China
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Hamers AAJ, Argmann C, Moerland PD, Koenis DS, Marinković G, Sokolović M, de Vos AF, de Vries CJM, van Tiel CM. Nur77-deficiency in bone marrow-derived macrophages modulates inflammatory responses, extracellular matrix homeostasis, phagocytosis and tolerance. BMC Genomics 2016; 17:162. [PMID: 26932821 PMCID: PMC4774191 DOI: 10.1186/s12864-016-2469-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 02/12/2016] [Indexed: 02/08/2023] Open
Abstract
Background The nuclear orphan receptor Nur77 (NR4A1, TR3, or NGFI-B) has been shown to modulate the inflammatory response of macrophages. To further elucidate the role of Nur77 in macrophage physiology, we compared the transcriptome of bone marrow-derived macrophages (BMM) from wild-type (WT) and Nur77-knockout (KO) mice. Results In line with previous observations, SDF-1α (CXCL12) was among the most upregulated genes in Nur77-deficient BMM and we demonstrated that Nur77 binds directly to the SDF-1α promoter, resulting in inhibition of SDF-1α expression. The cytokine receptor CX3CR1 was strongly downregulated in Nur77-KO BMM, implying involvement of Nur77 in macrophage tolerance. Ingenuity pathway analyses (IPA) to identify canonical pathways regulation and gene set enrichment analyses (GSEA) revealed a potential role for Nur77 in extracellular matrix homeostasis. Nur77-deficiency increased the collagen content of macrophage extracellular matrix through enhanced expression of several collagen subtypes and diminished matrix metalloproteinase (MMP)-9 activity. IPA upstream regulator analyses discerned the small GTPase Rac1 as a novel regulator of Nur77-mediated gene expression. We identified an inhibitory feedback loop with increased Rac1 activity in Nur77-KO BMM, which may explain the augmented phagocytic activity of these cells. Finally, we predict multiple chronic inflammatory diseases to be influenced by macrophage Nur77 expression. GSEA and IPA associated Nur77 to osteoarthritis, chronic obstructive pulmonary disease, rheumatoid arthritis, psoriasis, and allergic airway inflammatory diseases. Conclusions Altogether these data identify Nur77 as a modulator of macrophage function and an interesting target to treat chronic inflammatory disease. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2469-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Anouk A J Hamers
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. .,Present address: Department of Inflammation Biology, La Jolla Institute for Allergy and Immunology, San Diego, USA.
| | - Carmen Argmann
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. .,Present address: Institute for Genomics and Multiscale Biology Mount Sinai Hospital, New York, USA.
| | - Perry D Moerland
- Bioinformatics Laboratory, Department of Clinical Epidemiology, Biostatistics and Bioinformatics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Duco S Koenis
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Goran Marinković
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Milka Sokolović
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. .,Present address: European Food Information Council, Brussels, Belgium.
| | - Alex F de Vos
- Center for Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Carlie J M de Vries
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Claudia M van Tiel
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
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Abstract
PURPOSE OF REVIEW To offer a comprehensive review on the roles that oxysterols synthesized or engulfed by macrophages, or oxysterol-binding proteins in these cells, play in the development and progression of atherosclerotic lesions. RECENT FINDINGS Oxysterols abundant within the plaque have the capacity to potentiate macrophage proinflammatory signaling and to induce cell death. These activities may contribute to formation of the complex lesion, expansion of the necrotic core, and to plaque rupture. On the contrary, several endogenous oxysterols generated by cholesterol hydroxylases act as ligands of liver X receptors, stimulate macrophage cholesterol efflux, repress proinflammatory signaling, and promote macrophage survival, counteracting lesion progression. Cytoplasmic oxysterol-binding proteins represent a family of sterol and phosphoinositide sensors that may contribute to the regulatory impact of these bioactive lipids on processes relevant in the context of atherogenesis. SUMMARY The generation and deposition of oxysterols within the developing plaque is envisioned to modulate macrophage lipid metabolism, to affect the delicate balance of proinflammatory and anti-inflammatory processes, and to impact cell fate decisions, thus, determining whether the lesion remains benign or whether it develops into a hazardous, vulnerable plaque.
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Affiliation(s)
- Vesa M Olkkonen
- Minerva Foundation Institute for Medical Research bInstitute of Biomedicine, Anatomy, University of Helsinki, Helsinki, Finland.
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Gaudreault N, Kumar N, Olivas VR, Eberlé D, Rapp JH, Raffai RL. Macrophage-specific apoE gene repair reduces diet-induced hyperlipidemia and atherosclerosis in hypomorphic Apoe mice. PLoS One 2012; 7:e35816. [PMID: 22606237 PMCID: PMC3351426 DOI: 10.1371/journal.pone.0035816] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Accepted: 03/26/2012] [Indexed: 01/23/2023] Open
Abstract
Background Apolipoprotein (apo) E is best known for its ability to lower plasma cholesterol and protect against atherosclerosis. Although the liver is the major source of plasma apoE, extra-hepatic sources of apoE, including from macrophages, account for up to 10% of plasma apoE levels. This study examined the contribution of macrophage-derived apoE expression levels in diet-induced hyperlipidemia and atherosclerosis. Methodology/Principal Findings Hypomorphic apoE (Apoeh/h) mice expressing wildtype mouse apoE at ∼2–5% of physiological levels in all tissues were derived by gene targeting in embryonic stem cells. Cre-mediated gene repair of the Apoeh/h allele in Apoeh/hLysM-Cre mice raised apoE expression levels by 26 fold in freshly isolated peritoneal macrophages, restoring it to 37% of levels seen in wildtype mice. Chow-fed Apoeh/hLysM-Cre and Apoeh/h mice displayed similar plasma apoE and cholesterol levels (55.53±2.90 mg/dl versus 62.70±2.77 mg/dl, n = 12). When fed a high-cholesterol diet (HCD) for 16 weeks, Apoeh/hLysM-Cre mice displayed a 3-fold increase in plasma apoE and a concomitant 32% decrease in plasma cholesterol when compared to Apoeh/h mice (602.20±22.30 mg/dl versus 888.80±24.99 mg/dl, n = 7). On HCD, Apoeh/hLysM-Cre mice showed increased apoE immunoreactivity in lesional macrophages and liver-associated Kupffer cells but not hepatocytes. In addition, Apoeh/hLysM-Cre mice developed 35% less atherosclerotic lesions in the aortic root than Apoeh/h mice (167×103±16×103 µm2 versus 259×103±56×103 µm2, n = 7). This difference in atherosclerosis lesions size was proportional to the observed reduction in plasma cholesterol. Conclusions/Significance Macrophage-derived apoE raises plasma apoE levels in response to diet-induced hyperlipidemia and by such reduces atherosclerosis proportionally to the extent to which it lowers plasma cholesterol levels.
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Affiliation(s)
- Nathalie Gaudreault
- Department of Surgery, University of California San Francisco, VA Medical Center, San Francisco, California, United States of America
| | - Nikit Kumar
- Department of Surgery, University of California San Francisco, VA Medical Center, San Francisco, California, United States of America
| | - Victor R. Olivas
- Department of Surgery, University of California San Francisco, VA Medical Center, San Francisco, California, United States of America
| | - Delphine Eberlé
- Department of Surgery, University of California San Francisco, VA Medical Center, San Francisco, California, United States of America
| | - Joseph H. Rapp
- Department of Surgery, University of California San Francisco, VA Medical Center, San Francisco, California, United States of America
| | - Robert L. Raffai
- Department of Surgery, University of California San Francisco, VA Medical Center, San Francisco, California, United States of America
- * E-mail:
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Lammers B, Zhao Y, Hoekstra M, Hildebrand RB, Ye D, Meurs I, Van Berkel TJC, Van Eck M. Augmented atherogenesis in LDL receptor deficient mice lacking both macrophage ABCA1 and ApoE. PLoS One 2011; 6:e26095. [PMID: 22022523 PMCID: PMC3191178 DOI: 10.1371/journal.pone.0026095] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 09/19/2011] [Indexed: 11/18/2022] Open
Abstract
AIM ABCA1 protects against atherosclerosis by facilitating cholesterol efflux from macrophage foam cells in the arterial wall to extracellular apolipoprotein (apo) A-I. In contrast to apoA-I, apoE is secreted by macrophages and can, like apoA-I, induce ABCA1-mediated cholesterol efflux. Yet, the combined effect of macrophage ABCA1 and apoE on lesion development is unexplored. METHODS AND RESULTS LDL receptor knockout (KO) mice were transplanted with bone marrow from ABCA1/apoE double KO (dKO) mice, their respective single KO's, and wild-type (WT) controls and were challenged with a high-fat/high-cholesterol diet for 9 weeks. In vitro cholesterol efflux experiments showed no differences between ABCA1 KO and dKO macrophages. The serum non-HDL/HDL ratio in dKO transplanted mice was 1.7-fold and 2.4-fold (p<0.01) increased compared to WT and ABCA1 KO transplanted mice, respectively. The atherosclerotic lesion area in dKO transplanted animals (650±94×10(3) µm(2)), however, was 1.9-fold (p<0.01) and 1.6-fold (p<0.01) increased compared to single knockouts (ABCA1 KO: 341±20×10(3) µm(2); apoE KO: 402±78×10(3) µm(2), respectively) and 3.1-fold increased (p<0.001) compared to WT (211±20×10(3) µm(2)). When normalized for serum cholesterol exposure, macrophage ABCA1 and apoE independently protected against atherosclerotic lesion development (p<0.001). Moreover, hepatic expression levels of TNFα and IL-6 were highly induced in dKO transplanted animals (3.0-fold; p<0.05, and 4.3-fold; p<0.001, respectively). In agreement, serum IL-6 levels were also enhanced in ABCA1 KO transplanted mice (p<0.05) and even further enhanced in dKO transplanted animals (3.1-fold as compared to ABCA1 KO transplanted animals; p<0.05). CONCLUSIONS Combined deletion of macrophage ABCA1 and apoE results in a defect in cholesterol efflux and, compared to ABCA1 KO transplanted mice, elevated serum total cholesterol levels. Importantly, these mice also suffer from enhanced systemic and hepatic inflammation, together resulting in the observed augmented atherosclerotic lesion development.
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Affiliation(s)
- Bart Lammers
- Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Gorlaeus Laboratories, Leiden University, Leiden, The Netherlands.
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Kolovou GD, Kostakou PM, Anagnostopoulou KK. Familial hypercholesterolemia and triglyceride metabolism. Int J Cardiol 2011; 147:349-58. [DOI: 10.1016/j.ijcard.2010.08.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 06/24/2010] [Accepted: 08/08/2010] [Indexed: 12/14/2022]
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Shi W, Zhang Z, Chen MH, Angle JF, Matsumoto AH. Genes within the MHC region have a dramatic influence on radiation-enhanced atherosclerosis in mice. ACTA ACUST UNITED AC 2010; 3:409-13. [PMID: 20729504 DOI: 10.1161/circgenetics.110.957449] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND C3H/HeJ (C3H) mice develop much smaller atherosclerotic lesions than C57BL/6 (B6) mice when deficient in apolipoprotein E (apoE⁻(/)⁻) or fed an atherogenic diet. The 2 strains differ in H2 haplotypes, with B6 having H2(b) and C3H having H2(k). C3.SW-H2(b)/SnJ (C3.SW) is a congenic strain of C3H/HeJ in which H2(k) is replaced with H2(b). METHODS AND RESULTS We performed bone marrow transplantation and found that atherosclerosis-resistant C3.SW.apoE⁻(/)⁻ mice reconstituted with bone marrow from either C3.SW.apoE⁻(/)⁻ or B6.apoE⁻(/)⁻ mice after lethal irradiation had significantly larger atherosclerotic lesions than B6.apoE⁻(/)⁻ mice receiving identical treatments and much larger lesions than C3H.apoE⁻(/)⁻ mice reconstituted with syngeneic bone marrow. For syngeneic transplantation, C3.SW.apoE⁻(/)⁻ mice exhibited a 21-fold increase in lesion size over C3H.apoE⁻(/)⁻ mice (152 800±21 937 versus 7060±2290 μm²/section) and a near 4-fold increase over B6.apoE⁻(/)⁻ mice (40 529±4675 μm²/section). C3.SW.apoE⁻(/)⁻ mice reconstituted with syngeneic marrow exhibited enhanced lesion formation relative to those reconstituted with B6 marrow (152 800±21 937 versus 107 000±9374 μm²/section; P=0.067). Sublethal irradiation led to a 6-fold increase of lesion size in C3.SW.apoE⁻(/)⁻ mice (9795±2804 versus 1550±607 μm²/section; P=0.008). Wild-type C3.SW mice reconstituted with apoE(+/+) or apoE⁻(/)⁻ bone marrow had significantly larger atherosclerotic lesions than C3H mice receiving identical treatments on an atherogenic diet. CONCLUSIONS These results indicate that gene(s) within the H2 region have a dramatic impact on radiation-enhanced atherosclerosis, and their effect is conveyed partially through bone marrow-derived cells.
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Affiliation(s)
- Weibin Shi
- Department of Radiology, University of Virginia, Charlottesville, 22908, USA.
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Yuan Z, Miyoshi T, Bao Y, Sheehan JP, Matsumoto AH, Shi W. Microarray analysis of gene expression in mouse aorta reveals role of the calcium signaling pathway in control of atherosclerosis susceptibility. Am J Physiol Heart Circ Physiol 2009; 296:H1336-43. [PMID: 19304945 DOI: 10.1152/ajpheart.01095.2008] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Inbred mouse strains C57BL/6J (B6) and C3H/HeJ (C3H) exhibit a marked difference in atherosclerotic lesion formation when deficient in apolipoprotein E (apoE(-/-)), and the arterial wall has been identified as a source of the difference in atherosclerosis susceptibility. In the present study, differences in gene expression in aortic walls of the two strains were analyzed by microarrays. Total RNA was extracted from the aorta of 6-wk-old female B6 and C3H apoE(-/-) mice fed a chow or Western diet. There were 1,514 genes in chow fed mice and 590 genes in Western fed mice that were found to be differentially expressed between the two strains. Pathway analysis of differentially expressed genes suggested a role for the calcium signaling pathway in regulating atherosclerosis susceptibility. Oxidized LDL (oxLDL) induced a dose-dependent rise in cytosolic calcium levels in B6 endothelial cells. oxLDL-induced monocyte chemoattractant protein-1 production was inhibited by pretreatment with calcium chelator EGTA or intracellular calcium trapping compound BAPTA, indicating that calcium ions mediate the effect of oxLDL on monocyte chemoattractant protein-1 induction. The present findings demonstrate involvement of the calcium signaling pathway in the inflammatory process of atherogenesis.
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Affiliation(s)
- Zuobiao Yuan
- Department of Radiology, Univ. of Virginia, Box 801339, Snyder Bldg. 266, 480 Ray C. Hunt Dr., Fontaine Research Park, Charlottesville, VA 22908, USA
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Lammers B, Out R, Hildebrand RB, Quinn CM, Williamson D, Hoekstra M, Meurs I, Van Berkel TJC, Jessup W, Van Eck M. Independent protective roles for macrophage Abcg1 and Apoe in the atherosclerotic lesion development. Atherosclerosis 2009; 205:420-6. [PMID: 19217108 DOI: 10.1016/j.atherosclerosis.2009.01.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 01/09/2009] [Accepted: 01/12/2009] [Indexed: 11/25/2022]
Abstract
OBJECTIVE ATP-binding cassette transporter G1 (Abcg1) and apolipoprotein E (Apoe) play a role in macrophage cholesterol efflux and consequently the development of atherosclerosis. A possible interaction between Abcg1 and Apoe in cholesterol efflux was postulated, but the potential combined action of these proteins on atherosclerotic lesion formation is unclear. METHODS LDL receptor knockout (KO) mice were transplanted with bone marrow from Abcg1/Apoe double KO (dKO) mice, their respective single knockouts, and wild-type (WT) controls and challenged with a high-fat/high-cholesterol diet for 6 weeks to induce atherosclerosis. RESULTS No differences were found in serum lipid levels. The mean atherosclerotic lesion area in dKO transplanted animals (187+/-18x10(3)microm(2)) was 1.4-fold (p<0.01) increased compared to single knockouts (Abcg1 KO: 138+/-5x10(3)microm(2); Apoe KO: 131+/-7x10(3)microm(2)) and 1.9-fold (p<0.001) as compared to WT controls (97+/-15x10(3)microm(2)). In vitro cholesterol efflux experiments established that combined deletion of Abcg1 and Apoe leads to a larger attenuation of macrophage cholesterol efflux to HDL as compared to single knockouts. CONCLUSIONS Single deletion of macrophage Abcg1 or Apoe does lead to a moderate non-significant increase in atherosclerotic lesion development as tested by ANOVA, while combined deletion of Abcg1 and Apoe induces a more dramatic and significant increase in atherosclerosis. Our results indicate an additive, independent effect for both macrophage Abcg1 and Apoe in the prevention of atherosclerosis.
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Affiliation(s)
- Bart Lammers
- Gorlaeus Leiden/Amsterdam Center for Drug Research, Leiden University, The Netherlands.
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15
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Li Y, Gilbert TR, Matsumoto AH, Shi W. Effect of aging on fatty streak formation in a diet-induced mouse model of atherosclerosis. J Vasc Res 2007; 45:205-10. [PMID: 18063868 DOI: 10.1159/000112133] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2007] [Accepted: 09/06/2007] [Indexed: 11/19/2022] Open
Abstract
Age is considered to be a major risk factor for atherosclerosis, but it is unclear whether age has a direct effect on susceptibility to atherosclerosis. Wild-type mice develop fatty streak lesions in the aortic root only when fed a cholate-containing high fat/cholesterol diet. To investigate the influence of age on fatty streak formation, young (10 weeks) and old (53 weeks) female C57BL/6 mice were fed an atherogenic diet containing 15% fat, 1.25% cholesterol and 0.5% sodium cholate for 12 weeks. Atherosclerotic lesions at the aortic root were measured after cryosections were stained with oil red O. Results showed that old mice developed a comparable size of aortic lesions with young counterparts (5,600 +/- 2,480 vs. 6,457 +/- 1,537 microm2/section; p = 0.77), although old mice had significantly higher plasma cholesterol levels than young mice on the atherogenic diet (p < 0.05). Plasma levels of soluble vascular cell adhesion molecule 1 were significantly higher in old mice than in young mice on both chow and Western diets (p < 0.005). These data indicate that age has no direct effect on atherosclerosis susceptibility although it is accompanied by elevations in plasma cholesterol and vascular cell adhesion molecule 1 levels in C57BL/6 mice. Thus, increased cardiovascular events with age are probably related to a progressive increase in plaque size rather than to an increase in atherosclerosis susceptibility.
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Affiliation(s)
- Yuhua Li
- Department of Radiology, University of Virginia, Charlottesville, Va 22908, USA
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16
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Tennert C, Teupser D, Mueller MA, Wilfert W, Renner-Müller I, Stein O, Stein Y, Sippel AE, Wolf E, Thiery J. Effect of macrophage ApoE on atherosclerosis in LDL-receptor deficient mice. Biochem Biophys Res Commun 2007; 361:574-9. [PMID: 17669363 DOI: 10.1016/j.bbrc.2007.07.067] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2007] [Accepted: 07/08/2007] [Indexed: 11/22/2022]
Abstract
Apolipoprotein E (ApoE) plays an important role in the development of atherosclerosis. Previous studies provide evidence for an atheroprotective role of ApoE in mouse models on the ApoE deficient (ApoE-/-) background. However, it is not clear whether this is also true on the LDL-receptor deficient (LDLR-/-) background. Transgenic mice carrying hApoE coding sequences in a chicken lysozyme expression cassette were generated. Transgene expression was directed into macrophages, expressing low levels of hApoE. Expression of the hApoE transgene was not sufficient to correct hypercholesterolemia. However, lesion area at the brachiocephalic artery (BCA) was significantly reduced (-72%) in female hApoE transgenic mice on the LDLR-/- background. This was associated with increased cholesterol efflux in macrophages of transgenic animals on the ApoE-/- background. We conclude that over-expression of ApoE in macrophages might be useful as a therapeutic principle for the prevention of atherosclerosis.
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Affiliation(s)
- Carsten Tennert
- Institute of Laboratory Medicine, Clinical Chemistry and Molecular Diagnostics, University Hospital Leipzig, Liebigstr. 27, D-04103 Leipzig, Germany
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17
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Pei H, Wang Y, Miyoshi T, Zhang Z, Matsumoto AH, Helm GA, Tellides G, Shi W. Direct evidence for a crucial role of the arterial wall in control of atherosclerosis susceptibility. Circulation 2006; 114:2382-9. [PMID: 17101850 DOI: 10.1161/circulationaha.106.640185] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Inbred mouse strains C57BL/6J (B6) and C3H/HeJ (C3H) exhibit marked differences in atherosclerosis susceptibility. We sought to determine whether the difference in atherosclerosis susceptibility resides at the level of arterial walls. METHODS AND RESULTS Thoracic aortic segments from 8-week-old female B6 and C3H apolipoprotein E-deficient mice were transplanted into the infrarenal aorta of 10-week-old female F1 mice. After transplantation, recipients were maintained on a chow diet for 16 weeks. The donor aortic segments of B6 mice developed significantly larger atherosclerotic lesions than those of C3H (44,983+/-11,702 versus 5600+/-4885 microm2 per section; P=0.011). Expression of vascular cell adhesion molecule (VCAM)-1 by endothelial cells was examined both in vitro and in vivo. B6 mice expressed significantly more VCAM-1 than their C3H counterparts. Sequence analysis of VCAM-1 cDNA revealed a nucleotide difference in the coding region that resulted in substitution of an amino acid in the protein product. CONCLUSIONS These data provide direct proof that factors operating in the vessel wall, particularly endothelial cells, can serve as atherosclerosis modifiers and suggest a possibility for the contribution of VCAM-1 to atherosclerosis susceptibility.
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Affiliation(s)
- Hong Pei
- Department of Radiology, University of Virginia, Charlottesville, VA, USA
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18
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Tian J, Pei H, Sanders JM, Angle JF, Sarembock IJ, Matsumoto AH, Helm GA, Shi W. Hyperlipidemia is a major determinant of neointimal formation in LDL receptor-deficient mice. Biochem Biophys Res Commun 2006; 345:1004-9. [PMID: 16712797 DOI: 10.1016/j.bbrc.2006.04.180] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Accepted: 04/29/2006] [Indexed: 11/28/2022]
Abstract
LDL receptor-deficient (LDLR(-/-)) mice exhibit mild hyperlipidemia on a chow diet but develop severe hyperlipidemia on a high fat diet. In this study, we investigated neointimal formation after removal of the endothelium when LDLR(-/-) mice were fed chow or a Western diet containing 42% fat, 0.15% cholesterol, and 19.5% casein. At 10 weeks of age, female mice underwent endothelial denudation of the left common carotid artery. Two weeks after injury, neointimal formation was barely detectable in the injured vessel when mice developed mild hyperlipidemia on the chow diet. In contrast, neointimal lesions were obvious when mice developed severe hyperlipidemia on the Western diet. Immunohistochemical and histological analyses demonstrated the presence of macrophage foam cells and smooth muscle cells in neointimal lesions. The injured artery also exhibited a significant increase in medial area on the Western diet. Plasma levels of MCP-1 and soluble VCAM-1 were significantly elevated by feeding of the Western diet. These data indicate that hyperlipidemia aggravates neointimal growth in LDLR(-/-) mice by promoting foam cell formation and inflammation.
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Affiliation(s)
- Jing Tian
- Department of Radiology, University of Virginia, Charlottesville, VA 22908, USA
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