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Zhang L, Wu JH, Jean-Charles PY, Murali P, Zhang W, Jazic A, Kaur S, Nepliouev I, Stiber JA, Snow K, Freedman NJ, Shenoy SK. Phosphorylation of USP20 on Ser334 by IRAK1 promotes IL-1β-evoked signaling in vascular smooth muscle cells and vascular inflammation. J Biol Chem 2023; 299:104911. [PMID: 37311534 PMCID: PMC10362797 DOI: 10.1016/j.jbc.2023.104911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/11/2023] [Accepted: 06/05/2023] [Indexed: 06/15/2023] Open
Abstract
Reversible lysine-63 (K63) polyubiquitination regulates proinflammatory signaling in vascular smooth muscle cells (SMCs) and plays an integral role in atherosclerosis. Ubiquitin-specific peptidase 20 (USP20) reduces NFκB activation triggered by proinflammatory stimuli, and USP20 activity attenuates atherosclerosis in mice. The association of USP20 with its substrates triggers deubiquitinase activity; this association is regulated by phosphorylation of USP20 on Ser334 (mouse) or Ser333 (human). USP20 Ser333 phosphorylation was greater in SMCs of atherosclerotic segments of human arteries as compared with nonatherosclerotic segments. To determine whether USP20 Ser334 phosphorylation regulates proinflammatory signaling, we created USP20-S334A mice using CRISPR/Cas9-mediated gene editing. USP20-S334A mice developed ∼50% less neointimal hyperplasia than congenic WT mice after carotid endothelial denudation. WT carotid SMCs showed substantial phosphorylation of USP20 Ser334, and WT carotids demonstrated greater NFκB activation, VCAM-1 expression, and SMC proliferation than USP20-S334A carotids. Concordantly, USP20-S334A primary SMCs in vitro proliferated and migrated less than WT SMCs in response to IL-1β. An active site ubiquitin probe bound to USP20-S334A and USP20-WT equivalently, but USP20-S334A associated more avidly with TRAF6 than USP20-WT. IL-1β induced less K63-linked polyubiquitination of TRAF6 and less downstream NFκB activity in USP20-S334A than in WT SMCs. Using in vitro phosphorylation with purified IRAK1 and siRNA-mediated gene silencing of IRAK1 in SMCs, we identified IRAK1 as a novel kinase for IL-1β-induced USP20 Ser334 phosphorylation. Our findings reveal novel mechanisms regulating IL-1β-induced proinflammatory signaling: by phosphorylating USP20 Ser334, IRAK1 diminishes the association of USP20 with TRAF6 and thus augments NFκB activation, SMC inflammation, and neointimal hyperplasia.
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Affiliation(s)
- Lisheng Zhang
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Jiao-Hui Wu
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Pierre-Yves Jean-Charles
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Pavitra Murali
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Wenli Zhang
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Aeva Jazic
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Suneet Kaur
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Igor Nepliouev
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Jonathan A Stiber
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Kamie Snow
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA
| | - Neil J Freedman
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA; Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA.
| | - Sudha K Shenoy
- Department of Medicine (Cardiology), Duke University Medical Center, Durham, North Carolina, USA; Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA.
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Oue H, Yamazaki Y, Qiao W, Yuanxin C, Ren Y, Kurti A, Shue F, Parsons TM, Perkerson RB, Kawatani K, Wang N, Starling SC, Roy B, Mosneag IE, Aikawa T, Holm ML, Liu CC, Inoue Y, Sullivan PM, Asmann YW, Kim BY, Bu G, Kanekiyo T. LRP1 in vascular mural cells modulates cerebrovascular integrity and function in the presence of APOE4. JCI Insight 2023; 8:e163822. [PMID: 37036005 PMCID: PMC10132158 DOI: 10.1172/jci.insight.163822] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 02/17/2023] [Indexed: 04/11/2023] Open
Abstract
Cerebrovasculature is critical in maintaining brain homeostasis; its dysregulation often leads to vascular cognitive impairment and dementia (VCID) during aging. VCID is the second most prevalent cause of dementia in the elderly, after Alzheimer's disease (AD), with frequent cooccurrence of VCID and AD. While multiple factors are involved in the pathogenesis of AD and VCID, APOE4 increases the risk for both diseases. A major apolipoprotein E (apoE) receptor, the low-density lipoprotein receptor-related protein 1 (LRP1), is abundantly expressed in vascular mural cells (pericytes and smooth muscle cells). Here, we investigated how deficiency of vascular mural cell LRP1 affects the cerebrovascular system and cognitive performance using vascular mural cell-specific Lrp1-KO mice (smLrp1-/-) in a human APOE3 or APOE4 background. We found that spatial memory was impaired in the 13- to 16-month-old APOE4 smLrp1-/- mice but not in the APOE3 smLrp1-/- mice, compared with their respective littermate control mice. These disruptions in the APOE4 smLrp1-/- mice were accompanied with excess paravascular glial activation and reduced cerebrovascular collagen IV. In addition, blood-brain barrier (BBB) integrity was disrupted in the APOE4 smLrp1-/- mice. Together, our results suggest that vascular mural cell LRP1 modulates cerebrovasculature integrity and function in an APOE genotype-dependent manner.
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Affiliation(s)
| | | | | | | | - Yingxue Ren
- Department of Quantitative Health Sciences, and
| | | | - Francis Shue
- Department of Neuroscience
- Center for Regenerative Medicine, Mayo Clinic, Jacksonville, Florida, USA
| | - Tammee M. Parsons
- Department of Neuroscience
- Center for Regenerative Medicine, Mayo Clinic, Jacksonville, Florida, USA
| | - Ralph B. Perkerson
- Center for Regenerative Medicine, Mayo Clinic, Jacksonville, Florida, USA
| | | | | | | | | | | | | | | | | | | | - Patrick M. Sullivan
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | | | - Betty Y.S. Kim
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | | | - Takahisa Kanekiyo
- Department of Neuroscience
- Center for Regenerative Medicine, Mayo Clinic, Jacksonville, Florida, USA
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Zhang JM, Au DT, Sawada H, Franklin MK, Moorleghen JJ, Howatt DA, Wang P, Aicher BO, Hampton B, Migliorini M, Ni F, Mullick AE, Wani MM, Ucuzian AA, Lu HS, Muratoglu SC, Daugherty A, Strickland DK. LRP1 protects against excessive superior mesenteric artery remodeling by modulating angiotensin II-mediated signaling. JCI Insight 2023; 8:e164751. [PMID: 36472907 PMCID: PMC9977308 DOI: 10.1172/jci.insight.164751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022] Open
Abstract
Vascular smooth muscle cells (vSMCs) exert a critical role in sensing and maintaining vascular integrity. These cells abundantly express the low-density lipoprotein receptor-related protein 1 (LRP1), a large endocytic signaling receptor that recognizes numerous ligands, including apolipoprotein E-rich lipoproteins, proteases, and protease-inhibitor complexes. We observed the spontaneous formation of aneurysms in the superior mesenteric artery (SMA) of both male and female mice in which LRP1 was genetically deleted in vSMCs (smLRP1-/- mice). Quantitative proteomics revealed elevated abundance of several proteins in smLRP1-/- mice that are known to be induced by angiotensin II-mediated (AngII-mediated) signaling, suggesting that this pathway was dysregulated. Administration of losartan, an AngII type I receptor antagonist, or an angiotensinogen antisense oligonucleotide to reduce plasma angiotensinogen concentrations restored the normal SMA phenotype in smLRP1-/- mice and prevented aneurysm formation. Additionally, using a vascular injury model, we noted excessive vascular remodeling and neointima formation in smLRP1-/- mice that was restored by losartan administration. Together, these findings reveal that LRP1 regulates vascular integrity and remodeling of the SMA by attenuating excessive AngII-mediated signaling.
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Affiliation(s)
- Jackie M Zhang
- Center for Vascular and Inflammatory Diseases and
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dianaly T Au
- Center for Vascular and Inflammatory Diseases and
| | - Hisashi Sawada
- Saha Cardiovascular Research Center and Saha Aortic Center and
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | | | | | | | - Pengjun Wang
- Saha Cardiovascular Research Center and Saha Aortic Center and
| | - Brittany O Aicher
- Center for Vascular and Inflammatory Diseases and
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | | | - Fenge Ni
- Center for Vascular and Inflammatory Diseases and
| | | | | | - Areck A Ucuzian
- Center for Vascular and Inflammatory Diseases and
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Vascular Services, Baltimore Veterans Affairs Medical Center, Baltimore, Maryland, USA
| | - Hong S Lu
- Saha Cardiovascular Research Center and Saha Aortic Center and
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | | | - Alan Daugherty
- Saha Cardiovascular Research Center and Saha Aortic Center and
- Department of Physiology, University of Kentucky, Lexington, Kentucky, USA
| | - Dudley K Strickland
- Center for Vascular and Inflammatory Diseases and
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Wang Y, Starovoytov A, Murad AM, Hunker KL, Brunham LR, Li JZ, Saw J, Ganesh SK. Burden of Rare Genetic Variants in Spontaneous Coronary Artery Dissection With High-risk Features. JAMA Cardiol 2022; 7:1045-1055. [PMID: 36103205 PMCID: PMC9475437 DOI: 10.1001/jamacardio.2022.2970] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 06/24/2022] [Indexed: 07/28/2023]
Abstract
Importance The emerging genetic basis of spontaneous coronary artery dissection (SCAD) has been defined as both partially complex and monogenic in some patients, involving variants predominantly in genes known to underlie vascular connective tissue diseases (CTDs). The effect of these genetic influences has not been defined in high-risk SCAD phenotypes, and the identification of a high-risk subgroup of individuals may help to guide clinical genetic evaluations of SCAD. Objective To identify and quantify the burden of rare genetic variation in individuals with SCAD with high-risk clinical features. Design, Setting, and Participants Whole-exome sequencing (WES) was performed for subsequent case-control association analyses and individual variant annotation among individuals with high-risk SCAD. Genetic variants were annotated for pathogenicity by in-silico analysis of genes previously defined by sequencing for vascular CTDs and/or SCAD, as well as genes prioritized by genome-wide association study (GWAS) and colocalization of arterial expression quantitative trait loci. Unbiased genome-wide association analysis of the WES data was performed by comparing aggregated variants in individuals with SCAD to healthy matched controls or the Genome Aggregation Database (gnomAD). This study was conducted at a tertiary care center. Individuals in the Canadian SCAD Registry genetics study with a high-risk SCAD phenotype were selected and defined as peripartum SCAD, recurrent SCAD, or SCAD in an individual with family history of arteriopathy. Main Outcomes and Measures Burden of genetic variants defined by DNA sequencing in individuals with high-risk SCAD. Results This study included a total of 336 participants (mean [SD] age, 53.0 [9.5] years; 301 female participants [90%]). Variants in vascular CTD genes were identified in 17.0% of individuals (16 of 94) with high-risk SCAD and were enriched (OR, 2.6; 95% CI, 1.6-4.2; P = 7.8 × 10-4) as compared with gnomAD, with leading significant signals in COL3A1 (OR, 13.4; 95% CI, 4.9-36.2; P = 2.8 × 10-4) and Loeys-Dietz syndrome genes (OR, 7.9; 95% CI, 2.9-21.2; P = 2.0 × 10-3). Variants in GWAS-prioritized genes, observed in 6.4% of individuals (6 of 94) with high-risk SCAD, were also enriched (OR, 3.6; 95% CI, 1.6-8.2; P = 7.4 × 10-3). Variants annotated as likely pathogenic or pathogenic occurred in 4 individuals, in the COL3A1, TGFBR2, and ADAMTSL4 genes. Genome-wide aggregated variant testing identified novel associations with peripartum SCAD. Conclusions and Relevance In this genetic study, approximately 1 in 5 individuals with a high-risk SCAD phenotype harbored a rare genetic variant in genes currently implicated for SCAD. Genetic screening in this subgroup of individuals presenting with SCAD may be considered.
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Affiliation(s)
- Yu Wang
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor
| | - Andrew Starovoytov
- Division of Cardiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrea M. Murad
- Division of Genetic Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor
| | - Kristina L. Hunker
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor
| | - Liam R. Brunham
- Division of Cardiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
- Centre for Heart Lung Innovation, Department of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jun Z. Li
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor
| | - Jacqueline Saw
- Division of Cardiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Santhi K. Ganesh
- Division of Cardiovascular Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor
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Liu Z, Andraska E, Akinbode D, Mars W, Alvidrez RIM. LRP1 in the Vascular Wall. CURRENT PATHOBIOLOGY REPORTS 2022. [DOI: 10.1007/s40139-022-00231-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lipid accumulation and novel insight into vascular smooth muscle cells in atherosclerosis. J Mol Med (Berl) 2021; 99:1511-1526. [PMID: 34345929 DOI: 10.1007/s00109-021-02109-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 06/03/2021] [Accepted: 06/29/2021] [Indexed: 12/15/2022]
Abstract
Atherosclerosis is a chronic and progressive process. It is the most important pathological basis of cardiovascular disease and stroke. Vascular smooth muscle cells (VSMCs) are an essential cell type in atherosclerosis. Previous studies have revealed that VSMCs undergo phenotypic transformation in atherosclerosis to participate in the retention of atherogenic lipoproteins as well as the formation of the fibrous cap and the underlying necrotic core in plaques. The emergence of lineage-tracing studies indicates that the function and number of VSMCs in plaques have been greatly underestimated. In addition, recent studies have revealed that VSMCs make up at least 50% of the foam cell population in human and mouse atherosclerotic lesions. Therefore, understanding the formation of lipid-loaded VSMCs and their regulatory mechanisms is critical to elucidate the pathogenesis of atherosclerosis and to explore potential therapeutic targets. Moreover, combination of many complementary technologies such as lineage tracing, single-cell RNA sequencing (scRNA-seq), flow cytometry, and mass cytometry (CyTOF) with immunostaining has been performed to further understand the complex VSMC function. Correct identification of detrimental and beneficial processes may reveal successful therapeutic treatments targeting VSMCs and their derivatives during atherosclerosis. The purpose of this review is to summarize the process of lipid-loaded VSMC formation in atherosclerosis and to describe novel insight into VSMCs gained by using multiple advanced methods.
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Chen J, Su Y, Pi S, Hu B, Mao L. The Dual Role of Low-Density Lipoprotein Receptor-Related Protein 1 in Atherosclerosis. Front Cardiovasc Med 2021; 8:682389. [PMID: 34124208 PMCID: PMC8192809 DOI: 10.3389/fcvm.2021.682389] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 05/05/2021] [Indexed: 12/26/2022] Open
Abstract
Low-density lipoprotein receptor–related protein-1 (LRP1) is a large endocytic and signaling receptor belonging to the LDL receptor (LDLR) gene family and that is widely expressed in several tissues. LRP1 comprises a large extracellular domain (ECD; 515 kDa, α chain) and a small intracellular domain (ICD; 85 kDa, β chain). The deletion of LRP1 leads to embryonic lethality in mice, revealing a crucial but yet undefined role in embryogenesis and development. LRP1 has been postulated to participate in numerous diverse physiological and pathological processes ranging from plasma lipoprotein homeostasis, atherosclerosis, tumor evolution, and fibrinolysis to neuronal regeneration and survival. Many studies using cultured cells and in vivo animal models have revealed the important roles of LRP1 in vascular remodeling, foam cell biology, inflammation and atherosclerosis. However, its role in atherosclerosis remains controversial. LRP1 not only participates in the removal of atherogenic lipoproteins and proatherogenic ligands in the liver but also mediates the uptake of aggregated LDL to promote the formation of macrophage- and vascular smooth muscle cell (VSMC)-derived foam cells, which causes a prothrombotic transformation of the vascular wall. The dual and opposing roles of LRP1 may also represent an interesting target for atherosclerosis therapeutics. This review highlights the influence of LRP1 during atherosclerosis development, focusing on its dual role in vascular cells and immune cells.
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Affiliation(s)
- Jiefang Chen
- Department of Neurology, Tongji Medical College, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Ying Su
- Department of Neurology, Tongji Medical College, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Shulan Pi
- Department of Neurology, Tongji Medical College, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Hu
- Department of Neurology, Tongji Medical College, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
| | - Ling Mao
- Department of Neurology, Tongji Medical College, Union Hospital, Huazhong University of Science and Technology, Wuhan, China
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He Z, Wang G, Wu J, Tang Z, Luo M. The molecular mechanism of LRP1 in physiological vascular homeostasis and signal transduction pathways. Biomed Pharmacother 2021; 139:111667. [PMID: 34243608 DOI: 10.1016/j.biopha.2021.111667] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 04/07/2021] [Accepted: 04/23/2021] [Indexed: 01/10/2023] Open
Abstract
Interactions between vascular smooth muscle cells (VSMCs), endothelial cells (ECs), pericytes (PCs) and macrophages (MФ), the major components of blood vessels, play a crucial role in maintaining vascular structural and functional homeostasis. Low-density lipoprotein (LDL) receptor-related protein-1 (LRP1), a transmembrane receptor protein belonging to the LDL receptor family, plays multifunctional roles in maintaining endocytosis, homeostasis, and signal transduction. Accumulating evidence suggests that LRP1 modulates vascular homeostasis mainly by regulating vasoactive substances and specific intracellular signaling pathways, including the plasminogen activator inhibitor 1 (PAI-1) signaling pathway, platelet-derived growth factor (PDGF) signaling pathway, transforming growth factor-β (TGF-β) signaling pathway and vascular endothelial growth factor (VEGF) signaling pathway. The aim of the present review is to focus on recent advances in the discovery and mechanism of vascular homeostasis regulated by LRP1-dependent signaling pathways. These recent discoveries expand our understanding of the mechanisms controlling LRP1 as a target for studies on vascular complications.
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Affiliation(s)
- Zhaohui He
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Drug Discovery Reseach Center, Southwest Medical University, 319 Zhongshan Road, Luzhou, Sichuan 646000, China; Department of Clinical Medicine, the Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Gang Wang
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Drug Discovery Reseach Center, Southwest Medical University, 319 Zhongshan Road, Luzhou, Sichuan 646000, China; Laboratory for Cardiovascular Pharmacology of Department of Pharmacology, the School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China
| | - Jianbo Wu
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Drug Discovery Reseach Center, Southwest Medical University, 319 Zhongshan Road, Luzhou, Sichuan 646000, China; Laboratory for Cardiovascular Pharmacology of Department of Pharmacology, the School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China; Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, United States
| | - Zonghao Tang
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Drug Discovery Reseach Center, Southwest Medical University, 319 Zhongshan Road, Luzhou, Sichuan 646000, China; Laboratory for Cardiovascular Pharmacology of Department of Pharmacology, the School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.
| | - Mao Luo
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Drug Discovery Reseach Center, Southwest Medical University, 319 Zhongshan Road, Luzhou, Sichuan 646000, China; Laboratory for Cardiovascular Pharmacology of Department of Pharmacology, the School of Pharmacy, Southwest Medical University, Luzhou, Sichuan, China.
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Mineo C. Lipoprotein receptor signalling in atherosclerosis. Cardiovasc Res 2021; 116:1254-1274. [PMID: 31834409 DOI: 10.1093/cvr/cvz338] [Citation(s) in RCA: 87] [Impact Index Per Article: 29.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/01/2019] [Accepted: 12/10/2019] [Indexed: 12/11/2022] Open
Abstract
The founding member of the lipoprotein receptor family, low-density lipoprotein receptor (LDLR) plays a major role in the atherogenesis through the receptor-mediated endocytosis of LDL particles and regulation of cholesterol homeostasis. Since the discovery of the LDLR, many other structurally and functionally related receptors have been identified, which include low-density lipoprotein receptor-related protein (LRP)1, LRP5, LRP6, very low-density lipoprotein receptor, and apolipoprotein E receptor 2. The scavenger receptor family members, on the other hand, constitute a family of pattern recognition proteins that are structurally diverse and recognize a wide array of ligands, including oxidized LDL. Among these are cluster of differentiation 36, scavenger receptor class B type I and lectin-like oxidized low-density lipoprotein receptor-1. In addition to the initially assigned role as a mediator of the uptake of macromolecules into the cell, a large number of studies in cultured cells and in in vivo animal models have revealed that these lipoprotein receptors participate in signal transduction to modulate cellular functions. This review highlights the signalling pathways by which these receptors influence the process of atherosclerosis development, focusing on their roles in the vascular cells, such as macrophages, endothelial cells, smooth muscle cells, and platelets. Human genetics of the receptors is also discussed to further provide the relevance to cardiovascular disease risks in humans. Further knowledge of the vascular biology of the lipoprotein receptors and their ligands will potentially enhance our ability to harness the mechanism to develop novel prophylactic and therapeutic strategies against cardiovascular diseases.
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Affiliation(s)
- Chieko Mineo
- Department of Pediatrics and Cell Biology, Center for Pulmonary and Vascular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9063, USA
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Hepatic LDL receptor-related protein-1 deficiency alters mitochondrial dynamics through phosphatidylinositol 4,5-bisphosphate reduction. J Biol Chem 2021; 296:100370. [PMID: 33548224 PMCID: PMC7949165 DOI: 10.1016/j.jbc.2021.100370] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/28/2021] [Accepted: 02/01/2021] [Indexed: 11/30/2022] Open
Abstract
The LDL receptor-related protein 1 (LRP1) is a multifunctional transmembrane protein with endocytosis and signal transduction functions. Previous studies have shown that hepatic LRP1 deficiency exacerbates diet-induced steatohepatitis and insulin resistance via mechanisms related to increased lysosome and mitochondria permeability and dysfunction. The current study examined the impact of LRP1 deficiency on mitochondrial function in the liver. Hepatocytes isolated from liver-specific LRP1 knockout (hLrp1−/−) mice showed reduced oxygen consumption compared with control mouse hepatocytes. The mitochondria in hLrp1−/− mouse livers have an abnormal morphology and their membranes contain significantly less anionic phospholipids, including lower levels of phosphatidylethanolamine and cardiolipin that increase mitochondrial fission and impair fusion. Additional studies showed that LRP1 complexes with phosphatidylinositol 4-phosphate 5-kinase like protein-1 (PIP5KL1) and phosphatidylinositol 4-phosphate 5-kinase-1β (PIP5K1β). The absence of LRP1 reduces the levels of both PIP5KL1 and PIP5K1β in the plasma membrane and also lowers phosphatidylinositol(4,5) bisphosphate (PI(4,5)P2) levels in hepatocytes. These data indicate that LRP1 recruits PIP5KL1 and PIP5K1β to the plasma membrane for PI(4,5)P2 biosynthesis. The lack of LRP1 reduces lipid kinase expression, leading to lower PI(4,5)P2 levels, thereby decreasing the availability of this lipid metabolite in the cardiolipin biosynthesis pathway to cause cardiolipin reduction and the impairment in mitochondria homeostasis. Taken together, the current study identifies another signaling mechanism by which LRP1 regulates cell functions: binding and recruitment of PIP5KL1 and PIP5K1β to the membrane for PI(4,5)P2 synthesis. In addition, it highlights the importance of this mechanism for maintaining the integrity and functions of intracellular organelles.
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11
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Auderset L, Pitman KA, Cullen CL, Pepper RE, Taylor BV, Foa L, Young KM. Low-Density Lipoprotein Receptor-Related Protein 1 (LRP1) Is a Negative Regulator of Oligodendrocyte Progenitor Cell Differentiation in the Adult Mouse Brain. Front Cell Dev Biol 2020; 8:564351. [PMID: 33282858 PMCID: PMC7691426 DOI: 10.3389/fcell.2020.564351] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 09/14/2020] [Indexed: 12/17/2022] Open
Abstract
Low-density lipoprotein receptor-related protein 1 (LRP1) is a large, endocytic cell surface receptor that is highly expressed by oligodendrocyte progenitor cells (OPCs) and LRP1 expression is rapidly downregulated as OPCs differentiate into oligodendrocytes (OLs). We report that the conditional deletion of Lrp1 from adult mouse OPCs (Pdgfrα-CreER :: Lrp1fl/fl) increases the number of newborn, mature myelinating OLs added to the corpus callosum and motor cortex. As these additional OLs extend a normal number of internodes that are of a normal length, Lrp1-deletion increases adult myelination. OPC proliferation is also elevated following Lrp1 deletion in vivo, however, this may be a secondary, homeostatic response to increased OPC differentiation, as our in vitro experiments show that LRP1 is a direct negative regulator of OPC differentiation, not proliferation. Deleting Lrp1 from adult OPCs also increases the number of newborn mature OLs added to the corpus callosum in response to cuprizone-induced demyelination. These data suggest that the selective blockade of LRP1 function on adult OPCs may enhance myelin repair in demyelinating diseases such as multiple sclerosis.
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Affiliation(s)
- Loic Auderset
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Kimberley A Pitman
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Carlie L Cullen
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Renee E Pepper
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Bruce V Taylor
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Lisa Foa
- School of Medicine, University of Tasmania, Hobart, TAS, Australia
| | - Kaylene M Young
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
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12
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Guo Y, Yan B, Gui Y, Tang Z, Tai S, Zhou S, Zheng XL. Physiology and role of PCSK9 in vascular disease: Potential impact of localized PCSK9 in vascular wall. J Cell Physiol 2020; 236:2333-2351. [PMID: 32875580 DOI: 10.1002/jcp.30025] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 08/12/2020] [Accepted: 08/16/2020] [Indexed: 12/26/2022]
Abstract
Proprotein convertase subtilisin/kexin type-9 (PCSK9), a member of the proprotein convertase family, is an important drug target because of its crucial role in lipid metabolism. Emerging evidence suggests a direct role of localized PCSK9 in the pathogenesis of vascular diseases. With this in our consideration, we reviewed PCSK9 physiology with respect to recent development and major studies (clinical and experimental) on PCSK9 functionality in vascular disease. PCSK9 upregulates low-density lipoprotein (LDL)-cholesterol levels by binding to the LDL-receptor (LDLR) and facilitating its lysosomal degradation. PCSK9 gain-of-function mutations have been confirmed as a novel genetic mechanism for familial hypercholesterolemia. Elevated serum PCSK9 levels in patients with vascular diseases may contribute to coronary artery disease, atherosclerosis, cerebrovascular diseases, vasculitis, aortic diseases, and arterial aging pathogenesis. Experimental models of atherosclerosis, arterial aneurysm, and coronary or carotid artery ligation also support PCSK9 contribution to inflammatory response and disease progression, through LDLR-dependent or -independent mechanisms. More recently, several clinical trials have confirmed that anti-PCSK9 monoclonal antibodies can reduce systemic LDL levels, total nonfatal cardiovascular events, and all-cause mortality. Interaction of PCSK9 with other receptor proteins (LDLR-related proteins, cluster of differentiation family members, epithelial Na+ channels, and sortilin) may underlie its roles in vascular disease. Improved understanding of PCSK9 roles and molecular mechanisms in various vascular diseases will facilitate advances in lipid-lowering therapy and disease prevention.
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Affiliation(s)
- Yanan Guo
- Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, China.,Department of Biochemistry & Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
| | - Binjie Yan
- Department of Biochemistry & Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Pathophysiology, Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang, Hunan, China
| | - Yu Gui
- Department of Biochemistry & Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
| | - Zhihan Tang
- Department of Biochemistry & Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Pathophysiology, Institute of Cardiovascular Disease, Key Lab for Arteriosclerology of Hunan Province, University of South China, Hengyang, Hunan, China
| | - Shi Tai
- Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, China.,Department of Biochemistry & Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
| | - Shenghua Zhou
- Department of Cardiology, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Xi-Long Zheng
- Department of Biochemistry & Molecular Biology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada.,Department of Physiology & Pharmacology, Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, The University of Calgary, Calgary, Alberta, Canada
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13
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Au DT, Arai AL, Fondrie WE, Muratoglu SC, Strickland DK. Role of the LDL Receptor-Related Protein 1 in Regulating Protease Activity and Signaling Pathways in the Vasculature. Curr Drug Targets 2019; 19:1276-1288. [PMID: 29749311 DOI: 10.2174/1389450119666180511162048] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 04/24/2018] [Accepted: 04/24/2018] [Indexed: 12/22/2022]
Abstract
Aortic aneurysms represent a significant clinical problem as they largely go undetected until a rupture occurs. Currently, an understanding of mechanisms leading to aneurysm formation is limited. Numerous studies clearly indicate that vascular smooth muscle cells play a major role in the development and response of the vasculature to hemodynamic changes and defects in these responses can lead to aneurysm formation. The LDL receptor-related protein 1 (LRP1) is major smooth muscle cell receptor that has the capacity to mediate the endocytosis of numerous ligands and to initiate and regulate signaling pathways. Genetic evidence in humans and mouse models reveal a critical role for LRP1 in maintaining the integrity of the vasculature. Understanding the mechanisms by which this is accomplished represents an important area of research, and likely involves LRP1's ability to regulate levels of proteases known to degrade the extracellular matrix as well as its ability to modulate signaling events.
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Affiliation(s)
- Dianaly T Au
- Center for Vascular and Inflammatory Diseases, Biopark I, R213, 800 W. Baltimore Street, Baltimore, Maryland 21201, MD, United States
| | - Allison L Arai
- Center for Vascular and Inflammatory Diseases, Biopark I, R213, 800 W. Baltimore Street, Baltimore, Maryland 21201, MD, United States
| | - William E Fondrie
- Center for Vascular and Inflammatory Diseases, Biopark I, R213, 800 W. Baltimore Street, Baltimore, Maryland 21201, MD, United States
| | - Selen C Muratoglu
- Center for Vascular and Inflammatory Diseases, Biopark I, R213, 800 W. Baltimore Street, Baltimore, Maryland 21201, MD, United States.,Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, MD, United States
| | - Dudley K Strickland
- Center for Vascular and Inflammatory Diseases, Biopark I, R213, 800 W. Baltimore Street, Baltimore, Maryland 21201, MD, United States.,Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201, MD, United States.,Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland 21201, MD, United States
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14
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Zucker MM, Wujak L, Gungl A, Didiasova M, Kosanovic D, Petrovic A, Klepetko W, Schermuly RT, Kwapiszewska G, Schaefer L, Wygrecka M. LRP1 promotes synthetic phenotype of pulmonary artery smooth muscle cells in pulmonary hypertension. Biochim Biophys Acta Mol Basis Dis 2019; 1865:1604-1616. [PMID: 30910704 DOI: 10.1016/j.bbadis.2019.03.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 03/19/2019] [Accepted: 03/20/2019] [Indexed: 02/09/2023]
Abstract
Pulmonary hypertension (PH) is characterized by a thickening of the distal pulmonary arteries caused by medial hypertrophy, intimal proliferation and vascular fibrosis. Low density lipoprotein receptor-related protein 1 (LRP1) maintains vascular homeostasis by mediating endocytosis of numerous ligands and by initiating and regulating signaling pathways. Here, we demonstrate the increased levels of LRP1 protein in the lungs of idiopathic pulmonary arterial hypertension (IPAH) patients, hypoxia-exposed mice, and monocrotaline-treated rats. Platelet-derived growth factor (PDGF)-BB upregulated LRP1 expression in pulmonary artery smooth muscle cells (PASMC). This effect was reversed by the PDGF-BB neutralizing antibody or the PDGF receptor antagonist. Depletion of LRP1 decreased proliferation of donor and IPAH PASMC in a β1-integrin-dependent manner. Furthermore, LRP1 silencing attenuated the expression of fibronectin and collagen I and increased the levels of α-smooth muscle actin and myocardin in donor, but not in IPAH, PASMC. In addition, smooth muscle cell (SMC)-specific LRP1 knockout augmented α-SMA expression in pulmonary vessels and reduced SMC proliferation in 3D ex vivo murine lung tissue cultures. In conclusion, our results indicate that LRP1 promotes the dedifferentiation of PASMC from a contractile to a synthetic phenotype thus suggesting its contribution to vascular remodeling in PH.
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Affiliation(s)
- Marius M Zucker
- Department of Biochemistry, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Lukasz Wujak
- Department of Biochemistry, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Anna Gungl
- Ludwig Boltzmann Institute for Lung Vascular Research, Medical University Graz, Graz, Austria
| | - Miroslava Didiasova
- Department of Biochemistry, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Djuro Kosanovic
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, Giessen, Germany; Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - Aleksandar Petrovic
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Walter Klepetko
- Department of Thoracic Surgery, Medical University of Vienna, Vienna, Austria
| | - Ralph T Schermuly
- Department of Internal Medicine, Universities of Giessen and Marburg Lung Center, Giessen, Germany
| | - Grazyna Kwapiszewska
- Ludwig Boltzmann Institute for Lung Vascular Research, Medical University Graz, Graz, Austria
| | - Liliana Schaefer
- Goethe University, School of Medicine, Frankfurt am Main, Germany
| | - Malgorzata Wygrecka
- Department of Biochemistry, Universities of Giessen and Marburg Lung Center, Giessen, Germany.
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15
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Au DT, Ying Z, Hernández-Ochoa EO, Fondrie WE, Hampton B, Migliorini M, Galisteo R, Schneider MF, Daugherty A, Rateri DL, Strickland DK, Muratoglu SC. LRP1 (Low-Density Lipoprotein Receptor-Related Protein 1) Regulates Smooth Muscle Contractility by Modulating Ca 2+ Signaling and Expression of Cytoskeleton-Related Proteins. Arterioscler Thromb Vasc Biol 2018; 38:2651-2664. [PMID: 30354243 PMCID: PMC6214382 DOI: 10.1161/atvbaha.118.311197] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 09/12/2018] [Indexed: 01/12/2023]
Abstract
Objective- Mutations affecting contractile-related proteins in the ECM (extracellular matrix), microfibrils, or vascular smooth muscle cells can predispose the aorta to aneurysms. We reported previously that the LRP1 (low-density lipoprotein receptor-related protein 1) maintains vessel wall integrity, and smLRP1-/- mice exhibited aortic dilatation. The current study focused on defining the mechanisms by which LRP1 regulates vessel wall function and integrity. Approach and Results- Isometric contraction assays demonstrated that vasoreactivity of LRP1-deficient aortic rings was significantly attenuated when stimulated with vasoconstrictors, including phenylephrine, thromboxane receptor agonist U-46619, increased potassium, and L-type Ca2+ channel ligand FPL-64176. Quantitative proteomics revealed proteins involved in actin polymerization and contraction were significantly downregulated in aortas of smLRP1-/- mice. However, studies with calyculin A indicated that although aortic muscle from smLRP1-/- mice can contract in response to calyculin A, a role for LRP1 in regulating the contractile machinery is not revealed. Furthermore, intracellular calcium imaging experiments identified defects in calcium release in response to a RyR (ryanodine receptor) agonist in smLRP1-/- aortic rings and cultured vascular smooth muscle cells. Conclusions- These results identify a critical role for LRP1 in modulating vascular smooth muscle cell contraction by regulating calcium signaling events that potentially protect against aneurysm development.
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MESH Headings
- Actin Cytoskeleton/drug effects
- Actin Cytoskeleton/genetics
- Actin Cytoskeleton/metabolism
- Actin Cytoskeleton/ultrastructure
- Animals
- Aorta/metabolism
- Calcium Channels/genetics
- Calcium Channels/metabolism
- Calcium Signaling/drug effects
- Cytoskeletal Proteins/genetics
- Cytoskeletal Proteins/metabolism
- Female
- Gene Expression Regulation
- Low Density Lipoprotein Receptor-Related Protein-1
- Male
- Mice, Knockout
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/ultrastructure
- Receptors, LDL/deficiency
- Receptors, LDL/genetics
- Receptors, LDL/metabolism
- Ryanodine Receptor Calcium Release Channel/genetics
- Ryanodine Receptor Calcium Release Channel/metabolism
- Tissue Culture Techniques
- Tumor Suppressor Proteins/deficiency
- Tumor Suppressor Proteins/genetics
- Tumor Suppressor Proteins/metabolism
- Vasoconstriction/drug effects
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Dianaly T. Au
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Zhekang Ying
- Department of Medicine Cardiology Division, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Erick O. Hernández-Ochoa
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - William E. Fondrie
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Brian Hampton
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Mary Migliorini
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Saha Cardiovascular Research Center and Department of Physiology, University of Kentucky, Lexington, KY 40536, USA
| | - Rebeca Galisteo
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Martin F. Schneider
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Alan Daugherty
- Saha Cardiovascular Research Center and Department of Physiology, University of Kentucky, Lexington, KY 40536, USA
| | - Debra L. Rateri
- Saha Cardiovascular Research Center and Department of Physiology, University of Kentucky, Lexington, KY 40536, USA
| | - Dudley K. Strickland
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Selen C. Muratoglu
- Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, MD 21201, USA
- Department of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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16
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Lu D, Li J, Liu H, Foxa GE, Weaver K, Li J, Williams BO, Yang T. LRP1 Suppresses Bone Resorption in Mice by Inhibiting the RANKL-Stimulated NF-κB and p38 Pathways During Osteoclastogenesis. J Bone Miner Res 2018; 33:1773-1784. [PMID: 29750835 DOI: 10.1002/jbmr.3469] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 04/18/2018] [Accepted: 05/04/2018] [Indexed: 02/06/2023]
Abstract
Single-nucleotide polymorphisms in the LRP1 gene coding sequence are associated with low bone mass, and cell culture studies suggest that LRP1 plays a role in osteoblast proliferation and osteoblast-mediated osteoclastogenesis. However, the in vivo function of LRP1 in bone homeostasis has not been explored. In this work, we studied the osteoclast-specific role of LRP1 in bone homeostasis using a Ctsk-Cre;Lrp1f/f mouse model on the C57BL/6J background. These mice had a dramatically decreased trabecular bone mass with markedly more osteoclasts, while the osteoblast activity was unaffected or slightly increased. The cortical bone parameters were largely unaltered. Upon RANKL treatment, Lrp1-deficient bone marrow monocytes more efficiently differentiated into osteoclasts and showed elevated p65 NFκB and p38 signaling. Consistently, Lrp1-overexpressing Raw264.7 cells were desensitized to RANKL-induced p38 and p65 activation and osteoclastogenesis. Moreover, RANKL treatment led to a sharp decrease of LRP1 protein and RNA in BMMs. Overall, our data suggest that osteoclast-expressed LRP1 is a crucial regulator of bone mass. It inhibits the NFκB and p38 pathways and lessens the efficiency of RANKL-induced osteoclastogenesis. © 2018 American Society for Bone and Mineral Research.
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Affiliation(s)
- Di Lu
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Jianshuang Li
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Huadie Liu
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA.,State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, People's Republic of China
| | - Gabrielle E Foxa
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Kevin Weaver
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Jie Li
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA.,State Key Laboratory of Medical Genetics and School of Life Sciences, Central South University, Changsha, Hunan, People's Republic of China
| | - Bart O Williams
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA
| | - Tao Yang
- Program of Skeletal Disease and Tumor Metastasis, Center for Cancer and Cell Biology, Van Andel Research Institute, Grand Rapids, MI, USA
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17
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Alshahrani S, Rapoport RM, Zahedi K, Jiang M, Nieman M, Barone S, Meredith AL, Lorenz JN, Rubinstein J, Soleimani M. The non-diuretic hypotensive effects of thiazides are enhanced during volume depletion states. PLoS One 2017; 12:e0181376. [PMID: 28719636 PMCID: PMC5515454 DOI: 10.1371/journal.pone.0181376] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 06/29/2017] [Indexed: 12/25/2022] Open
Abstract
Thiazide derivatives including Hydrochlorothiazide (HCTZ) represent the most common treatment of mild to moderate hypertension. Thiazides initially enhance diuresis via inhibition of the kidney Na+-Cl- Cotransporter (NCC). However, chronic volume depletion and diuresis are minimal while lowered blood pressure (BP) is maintained on thiazides. Thus, a vasodilator action of thiazides is proposed, likely via Ca2+-activated K+ (BK) channels in vascular smooth muscles. This study ascertains the role of volume depletion induced by salt restriction or salt wasting in NCC KO mice on the non-diuretic hypotensive action of HCTZ. HCTZ (20mg/kg s.c.) lowered BP in 1) NCC KO on a salt restricted diet but not with normal diet; 2) in volume depleted but not in volume resuscitated pendrin/NCC dKO mice; the BP reduction occurs without any enhancement in salt excretion or reduction in cardiac output. HCTZ still lowered BP following treatment of NCC KO on salt restricted diet with paxilline (8 mg/kg, i.p.), a BK channel blocker, and in BK KO and BK/NCC dKO mice on salt restricted diet. In aortic rings from NCC KO mice on normal and low salt diet, HCTZ did not alter and minimally decreased maximal phenylephrine contraction, respectively, while contractile sensitivity remained unchanged. These results demonstrate 1) the non-diuretic hypotensive effects of thiazides are augmented with volume depletion and 2) that the BP reduction is likely the result of HCTZ inhibition of vasoconstriction through a pathway dependent on factors present in vivo, is unrelated to BK channel activation, and involves processes associated with intravascular volume depletion.
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Affiliation(s)
- Saeed Alshahrani
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
| | - Robert M. Rapoport
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
| | - Kamyar Zahedi
- Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, OH, United States of America
- Division of Nephrology, Department of Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
- Research Services, Veterans Affairs Medical Center, Cincinnati, OH, United States of America
| | - Min Jiang
- Division of Cardiology, Department of Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
| | - Michelle Nieman
- Department of Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
| | - Sharon Barone
- Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, OH, United States of America
- Division of Nephrology, Department of Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
- Research Services, Veterans Affairs Medical Center, Cincinnati, OH, United States of America
| | - Andrea L. Meredith
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - John N. Lorenz
- Department of Physiology, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
| | - Jack Rubinstein
- Division of Cardiology, Department of Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
| | - Manoocher Soleimani
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
- Center on Genetics of Transport and Epithelial Biology, University of Cincinnati, Cincinnati, OH, United States of America
- Division of Nephrology, Department of Medicine, University of Cincinnati, College of Medicine, Cincinnati, OH, United States of America
- Research Services, Veterans Affairs Medical Center, Cincinnati, OH, United States of America
- * E-mail:
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18
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Konaniah ES, Kuhel DG, Basford JE, Weintraub NL, Hui DY. Deficiency of LRP1 in Mature Adipocytes Promotes Diet-Induced Inflammation and Atherosclerosis-Brief Report. Arterioscler Thromb Vasc Biol 2017; 37:1046-1049. [PMID: 28473440 DOI: 10.1161/atvbaha.117.309414] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/14/2017] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Mice with adipocyte-specific inactivation of low-density lipoprotein receptor-related protein-1 (LRP1) are resistant to diet-induced obesity and hyperglycemia because of compensatory thermogenic response by muscle. However, the physiological function of LRP1 in mature adipocytes and its role in cardiovascular disease modulation are unknown. This study compared perivascular adipose tissues (PVAT) from wild-type (adLrp1+/+) and adipocyte-specific LRP1 knockout (adLrp1-/-) mice in modulation of atherosclerosis progression. APPROACH AND RESULTS Analysis of adipose tissues from adLrp1+/+ and adLrp1-/- mice after Western diet feeding for 16 weeks revealed that, in comparison to adLrp1+/+ mice, the adipocytes in adLrp1-/- mice were smaller, but their adipose tissues were more inflamed with increased monocyte-macrophage infiltration and inflammatory gene expression. The transplantation of PVAT from chow-fed adLrp1+/+ and adLrp1-/- mice into the area surrounding the carotid arteries of Ldlr-/- mice before feeding the Western diet revealed a contributory role of PVAT toward hypercholesterolemia-induced atherosclerosis. Importantly, recipients of adLrp1-/- PVAT displayed a 3-fold increase in atherosclerosis compared with adLrp1+/+ PVAT recipients. The increased atherosclerosis invoked by LRP1-deficient PVAT was associated with elevated monocyte-macrophage infiltration and inflammatory cytokine expression in the transplanted fat. CONCLUSIONS PVAT provide outside-in signals through the adventitia to modulate atherosclerotic lesion progression in response to hypercholesterolemia. Moreover, adipocytes with LRP1 deficiency are dysfunctional and more inflamed. This latter observation adds the adipose tissue to the list of anatomic sites where LRP1 expression is important to protect against diet-induced atherosclerosis.
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Affiliation(s)
- Eddy S Konaniah
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - David G Kuhel
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - Joshua E Basford
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - Neal L Weintraub
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.)
| | - David Y Hui
- From the Department of Pathology, University of Cincinnati College of Medicine, OH (E.S.K., J.E.B., D.G.K., D.Y.H.); and the Division of Cardiology, Department of Medicine, Medical College of Georgia at Augusta University (N.L.W.).
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19
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Alshahrani S, Rapoport RM, Soleimani M. Vascular contractile reactivity in hypotension due to reduced renal reabsorption of Na + and restricted dietary Na . NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2017; 390:321-326. [PMID: 28108829 PMCID: PMC10947747 DOI: 10.1007/s00210-017-1340-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 01/10/2017] [Indexed: 10/20/2022]
Abstract
Reduced renal Na+ reabsorption along with restricted dietary Na+ depletes intravascular plasma volume which can then result in hypotension. Whether hypotension occurs and the magnitude of hypotension depends in part on compensatory angiotensin II-mediated increased vascular resistance. We investigated whether the ability of vascular resistance to mitigate the hypotension was compromised by decreased contractile reactivity. In vitro reactivity was investigated in aorta from mouse models of reduced renal Na+ reabsorption and restricted dietary Na+ associated with considerable hypotension and renin-angiotensin system activation: (1) the Na+-Cl--Co-transporter (NCC) knockout (KO) with Na+ restricted diet (0.1%, 2 weeks) and (2) the relatively more severe pendrin (apical chloride/bicarbonate exchanger) and NCC double KO. Contractile sensitivity to KCl, phenylephrine, and/or U46619 remained unaltered in aorta from both models. Maximal KCl and phenylephrine contraction expressed as force/aorta length from NCC KO with Na+-restricted diet remained unaltered, while in pendrin/NCC double KO were reduced to 49 and 64%, respectively. Wet weight of aorta from NCC KO with Na+-restricted diet remained unaltered, while pendrin/NCC double KO was reduced to 67%, consistent with decreased medial width determined with Verhoeff-Van Gieson stain. These findings suggest that hypotension associated with severe intravascular volume depletion, as the result of decreased renal Na+ reabsorption, may in part be due to decreased contractile reactivity as a consequence of reduced vascular hypertrophy.
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Affiliation(s)
- Saeed Alshahrani
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Robert M Rapoport
- Department of Pharmacology and Cell Biophysics, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA.
| | - Manoocher Soleimani
- Research Service, Veterans Affairs Medical Center, Cincinnati, OH, 45220, USA
- Department of Medicine, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
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20
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Prasad JM, Young PA, Strickland DK. High Affinity Binding of the Receptor-associated Protein D1D2 Domains with the Low Density Lipoprotein Receptor-related Protein (LRP1) Involves Bivalent Complex Formation: CRITICAL ROLES OF LYSINES 60 AND 191. J Biol Chem 2016; 291:18430-9. [PMID: 27402839 DOI: 10.1074/jbc.m116.744904] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Indexed: 11/06/2022] Open
Abstract
The LDL receptor-related protein 1 (LRP1) is a large endocytic receptor that binds and mediates the endocytosis of numerous structurally diverse ligands. Currently, the basis for ligand recognition by LRP1 is not well understood. LRP1 requires a molecular chaperone, termed the receptor-associated protein (RAP), to escort the newly synthesized receptor from the endoplasmic reticulum to the Golgi. RAP is a three-domain protein that contains the following two high affinity binding sites for LRP1: one is located within domains 1 and 2, and one is located in its third domain. Studies on the interaction of the RAP third domain with LRP1 reveal critical contributions by lysine 256 and lysine 270 for this interaction. From these studies, a model for ligand recognition by this class of receptors has been proposed. Here, we employed surface plasmon resonance to investigate the binding of RAP D1D2 to LRP1. Our results reveal that the high affinity of D1D2 for LRP1 results from avidity effects mediated by the simultaneous interactions of lysine 60 in D1 and lysine 191 in D2 with sites on LRP1 to form a bivalent D1D2-LRP1 complex. When lysine 60 and 191 are both mutated to alanine, the binding of D1D2 to LRP1 is ablated. Our data also reveal that D1D2 is able to bind to a second distinct site on LRP1 to form a monovalent complex. The studies confirm the canonical model for ligand recognition by this class of receptors, which is initiated by pairs of lysine residues that dock into acidic pockets on the receptor.
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Affiliation(s)
- Joni M Prasad
- From the Center for Vascular and Inflammatory Disease and the Departments of Surgery and Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Patricia A Young
- From the Center for Vascular and Inflammatory Disease and the Departments of Surgery and Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
| | - Dudley K Strickland
- From the Center for Vascular and Inflammatory Disease and the Departments of Surgery and Physiology, University of Maryland School of Medicine, Baltimore, Maryland 21201
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Hamlin AN, Basford JE, Jaeschke A, Hui DY. LRP1 Protein Deficiency Exacerbates Palmitate-induced Steatosis and Toxicity in Hepatocytes. J Biol Chem 2016; 291:16610-9. [PMID: 27317662 DOI: 10.1074/jbc.m116.717744] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Indexed: 01/21/2023] Open
Abstract
LRP1 (LDL receptor-related protein-1) is a ubiquitous receptor with both cell signaling and ligand endocytosis properties. In the liver, LRP1 serves as a chylomicron remnant receptor and also participates in the transport of extracellular cathepsin D to the lysosome for prosaposin activation. The current study showed that in comparison with wild type mice, hepatocyte-specific LRP1 knock-out (hLrp1(-/-)) mice were more susceptible to fasting-induced lipid accumulation in the liver. Primary hepatocytes isolated from hLrp1(-/-) mice also accumulated more intracellular lipids and experienced higher levels of endoplasmic reticulum (ER) stress after palmitate treatment compared with similarly treated hLrp1(+/+) hepatocytes. Palmitate-treated hLrp1(-/-) hepatocytes displayed similar LC3-II levels, but the levels of p62 were elevated in comparison with palmitate-treated hLrp1(+/+) hepatocytes, suggesting that the elevated lipid accumulation in LRP1-defective hepatocytes was not due to defects in autophagosome formation but was due to impairment of lipophagic lipid hydrolysis in the lysosome. Additional studies showed increased palmitate-induced oxidative stress, mitochondrial and lysosomal permeability, and cell death in hLrp1(-/-) hepatocytes. Importantly, the elevated cell death and ER stress observed in hLrp1(-/-) hepatocytes were abrogated by E64D treatment, whereas inhibiting ER stress diminished cell death but not lysosomal permeabilization. Taken together, these results documented that LRP1 deficiency in hepatocytes promotes lipid accumulation and lipotoxicity through lysosomal-mitochondrial permeabilization and ER stress that ultimately result in cell death. Hence, LRP1 dysfunction may be a major risk factor in fatty liver disease progression.
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Affiliation(s)
| | - Joshua E Basford
- Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - Anja Jaeschke
- Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
| | - David Y Hui
- Pathology and Laboratory Medicine, Metabolic Diseases Research Center, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237
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22
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Ganguly R, Wen AM, Myer AB, Czech T, Sahu S, Steinmetz NF, Raman P. Anti-atherogenic effect of trivalent chromium-loaded CPMV nanoparticles in human aortic smooth muscle cells under hyperglycemic conditions in vitro. NANOSCALE 2016; 8:6542-6554. [PMID: 26935414 PMCID: PMC5136293 DOI: 10.1039/c6nr00398b] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Atherosclerosis, a major macrovascular complication associated with diabetes, poses a tremendous burden on national health care expenditure. Despite extensive efforts, cost-effective remedies are unknown. Therapies for atherosclerosis are challenged by a lack of targeted drug delivery approaches. Toward this goal, we turn to a biology-derived drug delivery system utilizing nanoparticles formed by the plant virus, Cowpea mosaic virus (CPMV). The aim herein is to investigate the anti-atherogenic potential of the beneficial mineral nutrient, trivalent chromium, loaded CPMV nanoparticles in human aortic smooth muscle cells (HASMC) under hyperglycemic conditions. A non-covalent loading protocol is established yielding CrCl3-loaded CPMV (CPMV-Cr) carrying 2000 drug molecules per particle. Using immunofluorescence microscopy, we show that CPMV-Cr is readily taken up by HASMC in vitro. In glucose (25 mM)-stimulated cells, 100 nM CPMV-Cr inhibits HASMC proliferation concomitant to attenuated proliferating cell nuclear antigen (PCNA, proliferation marker) expression. This is accompanied by attenuation in high glucose-induced phospho-p38 and pAkt expression. Moreover, CPMV-Cr inhibits the expression of pro-inflammatory cytokines, transforming growth factor-β (TGF-β) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), in glucose-stimulated HASMCs. Finally glucose-stimulated lipid uptake is remarkably abrogated by CPMV-Cr, revealed by Oil Red O staining. Together, these data provide key cellular evidence for an atheroprotective effect of CPMV-Cr in vascular smooth muscle cells (VSMC) under hyperglycemic conditions that may promote novel therapeutic ventures for diabetic atherosclerosis.
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Affiliation(s)
- Rituparna Ganguly
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272-0095, USA. and School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - Amy M Wen
- Department of Biomedical Engineering, 10990 Euclid Avenue and Case Western Reserve University, Cleveland, OH, USA
| | - Ashley B Myer
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272-0095, USA.
| | - Tori Czech
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272-0095, USA.
| | - Soumyadip Sahu
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272-0095, USA. and School of Biomedical Sciences, Kent State University, Kent, OH, USA
| | - Nicole F Steinmetz
- Department of Biomedical Engineering, 10990 Euclid Avenue and Case Western Reserve University, Cleveland, OH, USA and Department of Radiology, 10990 Euclid Avenue and Case Western Reserve University, Cleveland, OH, USA and Department of Materials Science and Engineering, 10990 Euclid Avenue and Case Western Reserve University, Cleveland, OH, USA and Department of Macromolecular Science and Engineering, 10990 Euclid Avenue and Case Western Reserve University, Cleveland, OH, USA and Case Comprehensive Cancer Center, 10990 Euclid Avenue and Case Western Reserve University, Cleveland, OH, USA
| | - Priya Raman
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, 4209 State Route 44, Rootstown, OH 44272-0095, USA. and School of Biomedical Sciences, Kent State University, Kent, OH, USA
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PDGFRβ signalling regulates local inflammation and synergizes with hypercholesterolaemia to promote atherosclerosis. Nat Commun 2015; 6:7770. [PMID: 26183159 PMCID: PMC4507293 DOI: 10.1038/ncomms8770] [Citation(s) in RCA: 103] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 06/05/2015] [Indexed: 02/07/2023] Open
Abstract
Platelet-derived growth factor (PDGF) is a mitogen and chemoattractant for vascular smooth muscle cells (VSMCs). However, the direct effects of PDGF receptor β (PDGFRβ) activation on VSMCs have not been studied in the context of atherosclerosis. Here, we present a new mouse model of atherosclerosis with an activating mutation in PDGFRβ. Increased PDGFRβ signaling induces chemokine secretion and leads to leukocyte accumulation in the adventitia and media of the aorta. Furthermore, PDGFRβD849V amplifies and accelerates atherosclerosis in hypercholesterolemic ApoE−/− or Ldlr−/− mice. Intriguingly, increased PDGFRβ signaling promotes advanced plaque formation at novel sites in the thoracic aorta and coronary arteries. However, deletion of the PDGFRβ-activated transcription factor STAT1 in VSMCs alleviates inflammation of the arterial wall and reduces plaque burden. These results demonstrate that PDGFRβ pathway activation has a profound effect on vascular disease and support the conclusion that inflammation in the outer arterial layers is a driving process for atherosclerosis.
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Moxon JV, Behl-Gilhotra R, Morton SK, Krishna SM, Seto SW, Biros E, Nataatmadja M, West M, Walker PJ, Norman PE, Golledge J. Plasma Low-density Lipoprotein Receptor-related Protein 1 Concentration is not Associated with Human Abdominal Aortic Aneurysm Presence. Eur J Vasc Endovasc Surg 2015; 50:466-73. [PMID: 26188720 DOI: 10.1016/j.ejvs.2015.06.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 06/06/2015] [Indexed: 12/29/2022]
Abstract
OBJECTIVE/BACKGROUND Recent genetic data suggest that a polymorphism of LRP1 is an independent risk factor for abdominal aortic aneurysm (AAA). The aims of this study were to assess whether plasma and aortic concentrations of low-density lipoprotein receptor-related protein 1 (LRP1) are associated with AAA, and to investigate the possible relevance of LRP1 to AAA pathophysiology. METHODS Three analyses were conducted. First, plasma LRP1 concentrations were measured in community-dwelling men with and without AAA (n = 189 and n = 309, respectively) using enzyme-linked immunosorbent assay. Second, Western blotting analyses were employed to compare the expression of LRP1 protein in aortic biopsies collected from patients with AAA and nonaneurysmal postmortem donors (n = 6/group). Finally, the effect of in vitro LRP1 blockade on matrix metalloprotease 9 (MMP9) clearance by vascular smooth muscle cells was assessed by zymography. RESULTS Plasma LRP1 concentrations did not differ between groups of men with and without AAA (median concentration 4.56 μg/mL [interquartile range {IQR} (3.39-5.96)] and 4.43 μg/mL [IQR 3.44-5.84], respectively; p = .48), and were not associated with AAA after adjusting for other risk factors (odds ratio 1.10 [95% confidence interval: 0.91-1.32]; p = 0.35). In contrast, LRP1 expression was approximately 3.4-fold lower in aortic biopsies recovered from patients with AAA compared with controls (median [IQR] expression 1.72 [0.94-3.14] and 5.91 [4.63-6.94] relative density units, respectively; p < .01). In vitro LRP1 blockade significantly reduced the ability of vascular smooth muscle cells to internalize extracellular MMP9. CONCLUSIONS These data suggest that aortic but not circulating LRP1 is downregulated in patients with AAA and indicates a possible role for this protein in clearing an aneurysm-relevant ligand.
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Affiliation(s)
- J V Moxon
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia
| | - R Behl-Gilhotra
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia
| | - S K Morton
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia
| | - S M Krishna
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia
| | - S W Seto
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia; National Institute of Complementary Medicine, University of Western Sydney, Campbelltown, NSW 2560, Australia
| | - E Biros
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia
| | - M Nataatmadja
- The Cardiovascular Research Group, Department of Medicine, University of Queensland, The Prince Charles Hospital, Brisbane, QLD 4032, Australia
| | - M West
- The Cardiovascular Research Group, Department of Medicine, University of Queensland, The Prince Charles Hospital, Brisbane, QLD 4032, Australia
| | - P J Walker
- School of Medicine, Discipline of Surgery and Centre for Clinical Research, University of Queensland, Herston, QLD 4072, Australia
| | - P E Norman
- School of Surgery, University of Western Australia, Perth, WA 6009, Australia
| | - J Golledge
- Queensland Research Centre for Peripheral Vascular Disease, College of Medicine and Dentistry, James Cook University, Townsville, QLD 4811, Australia; School of Medicine, Discipline of Surgery and Centre for Clinical Research, University of Queensland, Herston, QLD 4072, Australia; Department of Vascular and Endovascular Surgery, The Townsville Hospital, Townsville, QLD 4814, Australia.
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Lee WR, Sacharidou A, Behling-Kelly E, Oltmann SC, Zhu W, Ahmed M, Gerard RD, Hui DY, Abe JI, Shaul PW, Mineo C. PDZK1 prevents neointima formation via suppression of breakpoint cluster region kinase in vascular smooth muscle. PLoS One 2015; 10:e0124494. [PMID: 25886360 PMCID: PMC4401672 DOI: 10.1371/journal.pone.0124494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 03/02/2015] [Indexed: 01/21/2023] Open
Abstract
Scavenger receptor class B, type I (SR-BI) and its adaptor protein PDZK1 mediate responses to HDL cholesterol in endothelium. Whether the receptor-adaptor protein tandem serves functions in other vascular cell types is unknown. The current work determined the roles of SR-BI and PDZK1 in vascular smooth muscle (VSM). To evaluate possible VSM functions of SR-BI and PDZK1 in vivo, neointima formation was assessed 21 days post-ligation in the carotid arteries of wild-type, SR-BI-/- or PDZK1-/- mice. Whereas neointima development was negligible in wild-type and SR-BI-/-, there was marked neointima formation in PDZK1-/- mice. PDZK1 expression was demonstrated in primary mouse VSM cells, and compared to wild-type cells, PDZK1-/- VSM displayed exaggerated proliferation and migration in response to platelet derived growth factor (PDGF). Tandem affinity purification-mass spectrometry revealed that PDZK1 interacts with breakpoint cluster region kinase (Bcr), which contains a C-terminal PDZ binding sequence and is known to enhance responses to PDGF in VSM. PDZK1 interaction with Bcr in VSM was demonstrated by pull-down and by coimmunoprecipitation, and the augmented proliferative response to PDGF in PDZK1-/- VSM was abrogated by Bcr depletion. Furthermore, compared with wild-type Bcr overexpression, the introduction of a Bcr mutant incapable of PDZK1 binding into VSM cells yielded an exaggerated proliferative response to PDGF. Thus, PDZK1 has novel SR-BI-independent function in VSM that affords protection from neointima formation, and this involves PDZK1 suppression of VSM cell proliferation via an inhibitory interaction with Bcr.
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Affiliation(s)
- Wan Ru Lee
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Anastasia Sacharidou
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Erica Behling-Kelly
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Sarah C. Oltmann
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Weifei Zhu
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Mohamed Ahmed
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Robert D. Gerard
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - David Y. Hui
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Jun-ichi Abe
- Department of Medicine and the Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Philip W. Shaul
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail: (PS); (CM)
| | - Chieko Mineo
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- * E-mail: (PS); (CM)
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Davis FM, Rateri DL, Balakrishnan A, Howatt DA, Strickland DK, Muratoglu SC, Haggerty CM, Fornwalt BK, Cassis LA, Daugherty A. Smooth muscle cell deletion of low-density lipoprotein receptor-related protein 1 augments angiotensin II-induced superior mesenteric arterial and ascending aortic aneurysms. Arterioscler Thromb Vasc Biol 2014; 35:155-62. [PMID: 25395615 DOI: 10.1161/atvbaha.114.304683] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Low-density lipoprotein receptor-related protein 1 (LRP1), a multifunctional protein involved in endocytosis and cell signaling pathways, leads to several vascular pathologies when deleted in vascular smooth muscle cells (SMCs). The purpose of this study was to determine whether LRP1 deletion in SMCs influenced angiotensin II-induced arterial pathologies. APPROACH AND RESULTS LRP1 protein abundance was equivalent in selected arterial regions, but SMC-specific LRP1 depletion had no effect on abdominal and ascending aortic diameters in young mice. To determine the effects of LRP1 deficiency on angiotensin II vascular responses, SMC-specific LRP1 (smLRP1(+/+)) and smLRP1-deficient (smLRP1(-/-)) mice were infused with saline, angiotensin II, or norepinephrine. Several smLRP(-/-) mice died of superior mesenteric arterial (SMA) rupture during angiotensin II infusion. In surviving mice, angiotensin II profoundly augmented SMA dilation in smLRP1(-/-) mice. SMA dilation was blood pressure dependent as demonstrated by a similar response during norepinephrine infusion. SMA dilation was also associated with profound macrophage accumulation, but minimal elastin fragmentation. Angiotensin II infusion led to no significant differences in abdominal aorta diameters between smLRP1(+/+) and smLRP1(-/-) mice. In contrast, ascending aortic dilation was exacerbated markedly in angiotensin II-infused smLRP1(-/-) mice, but norepinephrine had no significant effect on either aortic region. Ascending aortas of smLRP1(-/-) mice infused with angiotensin II had minimal macrophage accumulation but significantly increased elastin fragmentation and mRNA abundance of several LRP1 ligands including MMP-2 (matrix metalloproteinase-2) and uPA (urokinase plasminogen activator). CONCLUSIONS smLRP1 deficiency had no effect on angiotensin II-induced abdominal aortic aneurysm formation. Conversely, angiotensin II infusion in smLRP1(-/-) mice exacerbated SMA and ascending aorta dilation. Dilation in these 2 regions had differential association with blood pressure and divergent pathological characteristics.
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Affiliation(s)
- Frank M Davis
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Debra L Rateri
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Anju Balakrishnan
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Deborah A Howatt
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Dudley K Strickland
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Selen C Muratoglu
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Christopher M Haggerty
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Brandon K Fornwalt
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Lisa A Cassis
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.)
| | - Alan Daugherty
- From the Saha Cardiovascular Research Center (F.M.D., D.L.R., A.B., D.A.H., C.M.H., B.K.F., A.D.), Department of Pediatrics (B.K.F.), Department of Pharmacology and Nutritional Sciences (L.A.C.), University of Kentucky, Lexington; and Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore (D.K.S., S.C.M.).
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Ulrich V, Konaniah ES, Lee WR, Khadka S, Shen YM, Herz J, Salmon JE, Hui DY, Shaul PW, Mineo C. Antiphospholipid antibodies attenuate endothelial repair and promote neointima formation in mice. J Am Heart Assoc 2014; 3:e001369. [PMID: 25315347 PMCID: PMC4323803 DOI: 10.1161/jaha.114.001369] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Background Antiphospholipid syndrome patients have antiphospholipid antibodies (aPLs) that promote thrombosis, and they have increased cardiovascular disease risk. Although the basis for the thrombosis has been well delineated, it is not known why antiphospholipid syndrome patients also have an increased prevalence of nonthrombotic vascular occlusion. The aims of this work were to determine if aPLs directly promote medial hypertrophy or neointima formation in mice and to identify the underlying mechanisms. Methods and Results Medial hypertrophy and neointima formation invoked by carotid artery endothelial denudation were evaluated in mice administered normal human IgG or aPLs. While aPLs had no effect on medial hypertrophy, they caused exaggerated neointima development. This was related to an aPL‐induced impairment in reendothelialization post denudation, and scratch assays in cell culture revealed that there are direct effects of aPLs on endothelium that retard cell migration. Further experiments showed that aPL antagonism of endothelial migration and repair is mediated by antibody recognition of β2‐glycoprotein I, apolipoprotein E receptor 2, and a decline in bioavailable NO. Consistent with these mechanisms, the adverse impacts of aPLs on reendothelialization and neointima formation were fully prevented by the NO donor molsidomine. Conclusions APLs blunt endothelial repair, and there is related aPL‐induced exaggeration in neointima formation after endothelial injury in mice. The initiating process entails NO deficiency mediated by β2‐glycoprotein I recognition by aPLs and apolipoprotein E receptor 2. The modulation of endothelial apolipoprotein E receptor 2 function or NO bioavailability may represent new interventions to prevent the nonthrombotic vascular occlusion and resulting cardiovascular disorders that afflict antiphospholipid syndrome patients.
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Affiliation(s)
- Victoria Ulrich
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX (V.U., W.R.L., S.K., P.W.S., C.M.)
| | - Eddy S Konaniah
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, OH (E.S.K., D.Y.H.)
| | - Wan-Ru Lee
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX (V.U., W.R.L., S.K., P.W.S., C.M.)
| | - Sadiksha Khadka
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX (V.U., W.R.L., S.K., P.W.S., C.M.)
| | - Yu-Min Shen
- Division of Hematology/Oncology, Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX (Y.M.S.)
| | - Joachim Herz
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX (J.H.)
| | - Jane E Salmon
- Department of Medicine, Hospital for Special Surgery, Weill Cornell Medical College, New York, NY (J.E.S.)
| | - David Y Hui
- Department of Pathology, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, OH (E.S.K., D.Y.H.)
| | - Philip W Shaul
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX (V.U., W.R.L., S.K., P.W.S., C.M.)
| | - Chieko Mineo
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX (V.U., W.R.L., S.K., P.W.S., C.M.)
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Covarrubias R, Wilhelm AJ, Major AS. Specific deletion of LDL receptor-related protein on macrophages has skewed in vivo effects on cytokine production by invariant natural killer T cells. PLoS One 2014; 9:e102236. [PMID: 25050824 PMCID: PMC4106787 DOI: 10.1371/journal.pone.0102236] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Accepted: 06/17/2014] [Indexed: 12/31/2022] Open
Abstract
Expression of molecules involved in lipid homeostasis such as the low density lipoprotein receptor (LDLr) on antigen presenting cells (APCs) has been shown to enhance invariant natural killer T (iNKT) cell function. However, the contribution to iNKT cell activation by other lipoprotein receptors with shared structural and ligand binding properties to the LDLr has not been described. In this study, we investigated whether a structurally related receptor to the LDLr, known as LDL receptor-related protein (LRP), plays a role in iNKT cell activation. We found that, unlike the LDLr which is highly expressed on all immune cells, the LRP was preferentially expressed at high levels on F4/80+ macrophages (MΦ). We also show that CD169+ MΦs, known to present antigen to iNKT cells, exhibited increased expression of LRP compared to CD169- MΦs. To test the contribution of MΦ LRP to iNKT cell activation we used a mouse model of MΦ LRP conditional knockout (LRP-cKO). LRP-cKO MΦs pulsed with glycolipid alpha-galactosylceramide (αGC) elicited normal IL-2 secretion by iNKT hybridoma and in vivo challenge of LRP-cKO mice led to normal IFN-γ, but blunted IL-4 response in both serum and intracellular expression by iNKT cells. Flow cytometric analyses show similar levels of MHC class-I like molecule CD1d on LRP-cKO MΦs and normal glycolipid uptake. Survey of the iNKT cell compartment in LRP-cKO mice revealed intact numbers and percentages and no homeostatic disruption as evidenced by the absence of programmed death-1 and Ly-49 surface receptors. Mixed bone marrow chimeras showed that the inability iNKT cells to make IL-4 is cell extrinsic and can be rescued in the presence of wild type APCs. Collectively, these data demonstrate that, although MΦ LRP may not be necessary for IFN-γ responses, it can contribute to iNKT cell activation by enhancing early IL-4 secretion.
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Affiliation(s)
- Roman Covarrubias
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Ashley J. Wilhelm
- Department of Medicine, Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
| | - Amy S. Major
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
- Department of Medicine, Division of Cardiovascular Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, United States of America
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Strickland DK, Au DT, Cunfer P, Muratoglu SC. Low-density lipoprotein receptor-related protein-1: role in the regulation of vascular integrity. Arterioscler Thromb Vasc Biol 2014; 34:487-98. [PMID: 24504736 DOI: 10.1161/atvbaha.113.301924] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Low-density lipoprotein receptor-related protein-1 (LRP1) is a large endocytic and signaling receptor that is widely expressed. In the liver, LRP1 plays an important role in regulating the plasma levels of blood coagulation factor VIII (fVIII) by mediating its uptake and subsequent degradation. fVIII is a key plasma protein that is deficient in hemophilia A and circulates in complex with von Willebrand factor. Because von Willebrand factor blocks binding of fVIII to LRP1, questions remain on the molecular mechanisms by which LRP1 removes fVIII from the circulation. LRP1 also regulates cell surface levels of tissue factor, a component of the extrinsic blood coagulation pathway. This occurs when tissue factor pathway inhibitor bridges the fVII/tissue factor complex to LRP1, resulting in rapid LRP1-mediated internalization and downregulation of coagulant activity. In the vasculature LRP1 also plays protective role from the development of aneurysms. Mice in which the lrp1 gene is selectively deleted in vascular smooth muscle cells develop a phenotype similar to the progression of aneurysm formation in human patient, revealing that these mice are ideal for investigating molecular mechanisms associated with aneurysm formation. Studies suggest that LRP1 protects against elastin fiber fragmentation by reducing excess protease activity in the vessel wall. These proteases include high-temperature requirement factor A1, matrix metalloproteinase 2, matrix metalloproteinase-9, and membrane associated type 1-matrix metalloproteinase. In addition, LRP1 regulates matrix deposition, in part, by modulating levels of connective tissue growth factor. Defining pathways modulated by LRP1 that lead to aneurysm formation and defining its role in thrombosis may allow for more effective intervention in patients.
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Affiliation(s)
- Dudley K Strickland
- From the Center for Vascular and Inflammatory Disease (D.K.S., D.T.A., P.C., S.C.M.), Departments of Surgery (D.K.S.), and Physiology (S.C.M.), University of Maryland School of Medicine, Baltimore
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Aledo R, Costales P, Ciudad C, Noé V, Llorente-Cortes V, Badimon L. Molecular and functional characterization of LRP1 promoter polymorphism c.1-25 C>G (rs138854007). Atherosclerosis 2014; 233:178-85. [PMID: 24529141 DOI: 10.1016/j.atherosclerosis.2013.12.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 11/20/2013] [Accepted: 12/05/2013] [Indexed: 10/25/2022]
Abstract
The transcription of the Low-density lipoprotein receptor-related protein (LRP1) is upregulated by aggregated LDL (agLDL) and angiotensin II (AngII) in human vascular smooth muscle cells (hVSMC). The polymorphism c.1-25C>G creates a new GC-box in the LRP1 promoter recognized by Sp1/Sp3 transcription factors. The aims of this study were 1) to evaluate the impact of c.1-25C>G polymorphism on LRP1 transcriptional activity and expression, and 2) to examine the response of c.1-25C>G LRP1 promoter to LDL and AngII. EMSA and Luciferase assays in HeLa cells showed that -25G promoter has enhanced basal transcriptional activity and specific Sp1/Sp3 binding. hVSMC with GG genotype (GG-hVSMC) had higher LRP1 mRNA and protein levels, respectively than CC genotype (CC-hVSMC). EMSA assays showed that the polymorphism determines scarce amount of SRE-B/SREBP-2 complex formation and the failure of agLDL to further reduce these SRE-B/SREBP-2 complexes. Taken together, these results suggest that c.1-25C>G, by difficulting SREBP-2 binding, prevents SREBP-2 displacement required for LRP1 promoter response to LDL. In contrast, c.1-25C>G strongly favours Sp1/Sp3 binding and AngII-induced activity in Sp1/Sp3 dependent manner in GG-hVSMC. This increase is functionally translated into a higher capacity of GG-hVSMC to become foam cells from agLDL in presence of AngII. These results suggest that c.1-25C>G determines a lack of response to agLDL and an exacerbated response to AngII. It is thus conceivable that the presence of the polymorphism would be easily translated to vascular alterations in the presence of the pro-hypertensive autacoid, AngII.
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Affiliation(s)
- R Aledo
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Autonomous University of Barcelona, Sant Antoni Mª Claret, 167, 08025 Barcelona, Spain
| | - P Costales
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Autonomous University of Barcelona, Sant Antoni Mª Claret, 167, 08025 Barcelona, Spain
| | - C Ciudad
- Biochemistry and Molecular Biology Department, School of Pharmacy, IBUB, University of Barcelona, Barcelona, Spain
| | - V Noé
- Biochemistry and Molecular Biology Department, School of Pharmacy, IBUB, University of Barcelona, Barcelona, Spain
| | - V Llorente-Cortes
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Autonomous University of Barcelona, Sant Antoni Mª Claret, 167, 08025 Barcelona, Spain.
| | - L Badimon
- Cardiovascular Research Center, CSIC-ICCC, Hospital de la Santa Creu i Sant Pau, IIB-Sant Pau, Autonomous University of Barcelona, Sant Antoni Mª Claret, 167, 08025 Barcelona, Spain
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Smooth muscle LDL receptor-related protein-1 deletion induces aortic insufficiency and promotes vascular cardiomyopathy in mice. PLoS One 2013; 8:e82026. [PMID: 24312398 PMCID: PMC3843717 DOI: 10.1371/journal.pone.0082026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 10/28/2013] [Indexed: 11/19/2022] Open
Abstract
Valvular disease is common in patients with Marfan syndrome and can lead to cardiomyopathy. However, some patients develop cardiomyopathy in the absence of hemodynamically significant valve dysfunction, suggesting alternative mechanisms of disease progression. Disruption of LDL receptor-related protein-1 (Lrp1) in smooth muscle cells has been shown to cause vascular pathologies similar to Marfan syndrome, with activation of smooth muscle cells, vascular dysfunction and aortic aneurysms. This study used echocardiography and blood pressure monitoring in mouse models to determine whether inactivation of Lrp1 in vascular smooth muscle leads to cardiomyopathy, and if so, whether the mechanism is a consequence of valvular disease. Hemodynamic changes during treatment with captopril were also assessed. Dilation of aortic roots was observed in young Lrp1-knockout mice and progressed as they aged, whereas no significant aortic dilation was detected in wild type littermates. Diastolic blood pressure was lower and pulse pressure higher in Lrp1-knockout mice, which was normalized by treatment with captopril. Aortic dilation was followed by development of aortic insufficiency and subsequent dilated cardiomyopathy due to valvular disease. Thus, smooth muscle cell Lrp1 deficiency results in aortic dilation and insufficiency that causes secondary cardiomyopathy that can be improved by captopril. These findings provide novel insights into mechanisms of cardiomyopathy associated with vascular activation and offer a new model of valvular cardiomyopathy.
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Craig J, Mikhailenko I, Noyes N, Migliorini M, Strickland DK. The LDL receptor-related protein 1 (LRP1) regulates the PDGF signaling pathway by binding the protein phosphatase SHP-2 and modulating SHP-2- mediated PDGF signaling events. PLoS One 2013; 8:e70432. [PMID: 23922991 PMCID: PMC3724782 DOI: 10.1371/journal.pone.0070432] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/18/2013] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The PDGF signaling pathway plays a major role in several biological systems, including vascular remodeling that occurs following percutaneous transluminal coronary angioplasty. Recent studies have shown that the LDL receptor-related protein 1 (LRP1) is a physiological regulator of the PDGF signaling pathway. The underlying mechanistic details of how this regulation occurs have yet to be resolved. Activation of the PDGF receptor β (PDGFRβ) leads to tyrosine phosphorylation of the LRP1 cytoplasmic domain within endosomes and generates an LRP1 molecule with increased affinity for adaptor proteins such as SHP-2 that are involved in signaling pathways. SHP-2 is a protein tyrosine phosphatase that positively regulates the PDGFRβ pathway, and is required for PDGF-mediated chemotaxis. We investigated the possibility that LRP1 may regulate the PDGFRβ signaling pathway by binding SHP-2 and competing with the PDGFRβ for this molecule. METHODOLOGY/PRINCIPAL FINDINGS To quantify the interaction between SHP-2 and phosphorylated forms of the LRP1 intracellular domain, we utilized an ELISA with purified recombinant proteins. These studies revealed high affinity binding of SHP-2 to phosphorylated forms of both LRP1 intracellular domain and the PDGFRβ kinase domain. By employing the well characterized dynamin inhibitor, dynasore, we established that PDGF-induced SHP-2 phosphorylation primarily occurs within endosomal compartments, the same compartments in which LRP1 is tyrosine phosphorylated by activated PDGFRβ. Immunofluorescence studies revealed colocalization of LRP1 and phospho-SHP-2 following PDGF stimulation of fibroblasts. To define the contribution of LRP1 to SHP-2-mediated PDGF chemotaxis, we employed fibroblasts expressing LRP1 and deficient in LRP1 and a specific SHP-2 inhibitor, NSC-87877. Our results reveal that LRP1 modulates SHP-2-mediated PDGF-mediated chemotaxis. CONCLUSIONS/SIGNIFICANCE Our data demonstrate that phosphorylated forms of LRP1 and PDGFRβ compete for SHP-2 binding, and that expression of LRP1 attenuates SHP-2-mediated PDGF signaling events.
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Affiliation(s)
- Julie Craig
- Center for Vascular and Inflammatory Diseases and
| | - Irina Mikhailenko
- Center for Vascular and Inflammatory Diseases and
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | | | - Mary Migliorini
- Center for Vascular and Inflammatory Diseases and
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Dudley K. Strickland
- Center for Vascular and Inflammatory Diseases and
- Department of Physiology, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
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Muratoglu SC, Belgrave S, Hampton B, Migliorini M, Coksaygan T, Chen L, Mikhailenko I, Strickland DK. LRP1 protects the vasculature by regulating levels of connective tissue growth factor and HtrA1. Arterioscler Thromb Vasc Biol 2013; 33:2137-46. [PMID: 23868935 DOI: 10.1161/atvbaha.113.301893] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVE Low-density lipoprotein receptor-related protein 1 (LRP1) is a large endocytic and signaling receptor that is abundant in vascular smooth muscle cells. Mice in which the lrp1 gene is deleted in smooth muscle cells (smLRP1(-/-)) on a low-density lipoprotein receptor-deficient background display excessive platelet derived growth factor-signaling, smooth muscle cell proliferation, aneurysm formation, and increased susceptibility to atherosclerosis. The objectives of the current study were to examine the potential of LRP1 to modulate vascular physiology under nonatherogenic conditions. APPROACH AND RESULTS We found smLRP1(-/-) mice to have extensive in vivo aortic dilatation accompanied by disorganized and degraded elastic lamina along with medial thickening of the arterial vessels resulting from excess matrix deposition. Surprisingly, this was not attributable to excessive platelet derived growth factor-signaling. Rather, quantitative differential proteomic analysis revealed that smLRP1(-/-) vessels contain a 4-fold increase in protein levels of high-temperature requirement factor A1 (HtrA1), which is a secreted serine protease that is known to degrade matrix components and to impair elastogenesis, resulting in fragmentation of elastic fibers. Importantly, our study discovered that HtrA1 is a novel LRP1 ligand. Proteomics analysis also identified excessive accumulation of connective tissue growth factor, an LRP1 ligand and a key mediator of fibrosis. CONCLUSIONS Our findings suggest a critical role for LRP1 in maintaining the integrity of vessels by regulating protease activity as well as matrix deposition by modulating HtrA1 and connective tissue growth factor protein levels. This study highlights 2 new molecules, connective tissue growth factor and HtrA1, which contribute to detrimental changes in the vasculature and, therefore, represent new target molecules for potential therapeutic intervention to maintain vessel wall homeostasis.
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Affiliation(s)
- Selen C Muratoglu
- Center for Vascular and Inflammatory Disease, Departments of Physiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
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34
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Cal R, García-Arguinzonis M, Revuelta-López E, Castellano J, Padró T, Badimon L, Llorente-Cortés V. Aggregated Low-Density Lipoprotein Induces LRP1 Stabilization Through E3 Ubiquitin Ligase CHFR Downregulation in Human Vascular Smooth Muscle Cells. Arterioscler Thromb Vasc Biol 2013; 33:369-77. [DOI: 10.1161/atvbaha.112.300748] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Roi Cal
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Maisa García-Arguinzonis
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Elena Revuelta-López
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - José Castellano
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Teresa Padró
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Lina Badimon
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Vicenta Llorente-Cortés
- From the Cardiovascular Research Center of Barcelona, CSIC-ICCC, IIB-SantPau, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
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Wild J, Stather P, Sylvius N, Choke E, Sayers R, Bown M. Low Density Lipoprotein Receptor Related Protein 1 and Abdominal Aortic Aneurysms. Eur J Vasc Endovasc Surg 2012; 44:127-32. [DOI: 10.1016/j.ejvs.2012.05.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 05/08/2012] [Indexed: 12/15/2022]
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36
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Chung JH, Jeon HJ, Hong SY, Lee DL, Lee KH, Kim SH, Han YS, Manabe I, Miller YI, Lee SH. Palmitate promotes the paracrine effects of macrophages on vascular smooth muscle cells: the role of bone morphogenetic proteins. PLoS One 2012; 7:e29100. [PMID: 22363399 PMCID: PMC3283596 DOI: 10.1371/journal.pone.0029100] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2011] [Accepted: 11/21/2011] [Indexed: 01/22/2023] Open
Abstract
Saturated fatty acids are known to activate macrophages and induce vascular inflammation. Although cytokines from activated macrophage influence other vascular cells, the influence of saturated fatty acids on the paracrine effect of macrophages is not fully understood yet. Here we examined the impact of palmitate on the effect of macrophages on vascular smooth muscle cells (SMCs) and their mediators. SMCs proliferation increased significantly after treatment with conditioned media from palmitate-stimulated RAW264.7 cells. SMC migration was found to be greater after treatment with palmitate-conditioned media. SM α-actin and SM22α were decreased in SMCs treated with palmitate-conditioned media. When stimulated with palmitate, RAW264.7 cells secreted more bone morphogenetic protein (BMP)2 and BMP4 into the cell culture media. SMC proliferation, migration, and phenotypic changes were attenuated after treatment of neutralizing antibodies against BMPs or knockdown of BMPs with siRNA. The influences of these proteins were further confirmed by direct treatment of recombinant BMP2 and BMP4 on SMCs. Particularly, the effects of BMPs on SMC migration on phenotypic change were obvious, whereas their effect on SMC proliferation seemed not significant or modest. In conclusion, palmitate promoted macrophages' paracrine effects on SMC proliferation, migration, and phenotypic change. The effect of stimulated macrophages was mediated, at least in part, by BMP2 and BMP4. These results suggest a novel mechanism linking saturated fatty acids and the progression of vascular diseases that is possibly mediated by BMPs from macrophages.
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Affiliation(s)
- Ji Hyung Chung
- Cardiovascular Product Evaluation Center, Cardiovascular Research Institute, Yonsei University Health System, Seoul, Korea
| | - Hyun Ju Jeon
- Interdisciplinary Course of Science for Aging, Graduate School, Yonsei University, Seoul, Korea
| | - Sung-Yu Hong
- Cardiovascular Product Evaluation Center, Cardiovascular Research Institute, Yonsei University Health System, Seoul, Korea
| | - Da Lyung Lee
- National Research Laboratory for Cardiovascular Therapy, Biobud Inc., Seoul, Korea
| | - Kyung Hye Lee
- Yonsei Research Institute of Aging Science, Yonsei University, Seoul, Korea
| | - Soo Hyuk Kim
- Interdisciplinary Course of Science for Aging, Graduate School, Yonsei University, Seoul, Korea
| | - Ye Sun Han
- Department of Advanced Technology Fusion, Konkuk University, Seoul, Korea
| | - Ichiro Manabe
- Department of Cardiovascular Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yury I. Miller
- Department of Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Sang-Hak Lee
- Cardiology Division, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
- * E-mail:
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Basford JE, Wancata L, Hofmann SM, Silva RAGD, Davidson WS, Howles PN, Hui DY. Hepatic deficiency of low density lipoprotein receptor-related protein-1 reduces high density lipoprotein secretion and plasma levels in mice. J Biol Chem 2011; 286:13079-87. [PMID: 21343303 DOI: 10.1074/jbc.m111.229369] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The low density lipoprotein receptor-related protein-1 (LRP1) is known to serve as a chylomicron remnant receptor in the liver responsible for the binding and plasma clearance of apolipoprotein E-containing lipoproteins. Previous in vitro studies have provided evidence to suggest that LRP1 expression may also influence high density lipoprotein (HDL) metabolism. The current study showed that liver-specific LRP1 knock-out (hLrp1(-/-)) mice displayed lower fasting plasma HDL cholesterol levels when compared with hLrp1(+/+) mice. Lecithin:cholesterol acyl transferase and hepatic lipase activities in plasma of hLrp1(-/-) mice were comparable with those observed in hLrp1(+/+) mice, indicating that hepatic LRP1 inactivation does not influence plasma HDL remodeling. Plasma clearance of HDL particles and HDL-associated cholesteryl esters was also similar between hLrp1(+/+) and hLrp1(-/-) mice. In contrast, HDL secretion from primary hepatocytes isolated from hLrp1(-/-) mice was significantly reduced when compared with that observed with hLrp1(+/+) hepatocytes. Biotinylation of cell surface proteins revealed decreased surface localization of the ATP-binding cassette, subfamily A, member 1 (ABCA1) protein, but total cellular ABCA1 level was not changed in hLrp1(-/-) hepatocytes. Finally, hLrp1(-/-) hepatocytes displayed reduced binding capacity for extracellular cathepsin D, resulting in lower intracellular cathepsin D content and impairment of prosaposin activation, a process that is required for membrane translocation of ABCA1 to facilitate cholesterol efflux and HDL secretion. Taken together, these results documented that hepatic LRP1 participates in cellular activation of lysosomal enzymes and through this mechanism, indirectly modulates the production and plasma levels of HDL.
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Affiliation(s)
- Joshua E Basford
- Department of Pathology and Laboratory Medicine, Metabolic Diseases Institute, University of Cincinnati College of Medicine, Cincinnati, Ohio 45237, USA
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Apolipoprotein E inhibits toll-like receptor (TLR)-3- and TLR-4-mediated macrophage activation through distinct mechanisms. Biochem J 2010; 428:47-54. [PMID: 20218969 DOI: 10.1042/bj20100016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Previous studies have shown that apoE (apolipoprotein E) expression in macrophages suppresses inflammatory responses; however, whether endogenously synthesized apoE acts intracellularly or after its secretion in suppressing macrophage inflammation remains unclear. The present study used the murine monocyte macrophage cell line RAW 264.7 to examine the influence of exogenous apoE on macrophage inflammatory responses induced by TLR (Toll-like receptor)-4 and TLR-3 agonists LPS (lipopolysaccharide) and poly(I-C) respectively. Results showed that exogenously added apoE suppressed the LPS and poly(I-C) induction of IL (interleukin)-6, IL-1beta and TNF-alpha (tumour necrosis factor-alpha) secretion by RAW 264.7 cells. The mechanism was related to apoE suppression of TLR-agonist-induced phosphorylation of JNK (c-Jun N-terminal kinase) and c-Jun. A peptide containing the tandem repeat sequence of the receptor-binding domain of apoE, apoE-(141-155)2, was similarly effective in inhibiting LPS- and poly(I-C)-induced macrophage inflammatory responses. Reductive methylation of lysine residues in apoE, which abolished its receptor-binding capability without affecting its ability to interact with HSPGs (heparin sulfate proteoglycans), inhibited the ability of apoE to suppress macrophage responses to LPS, but had no effect on apoE suppression of poly(I-C)-induced macrophage activation. The ability of apoE to suppress poly(I-C)-induced pro-inflammatory cytokine production was abolished by heparinase treatment of RAW 264.7 cells to remove cell-surface HSPGs. Taken together, these results indicate that exogenous apoE inhibits macrophage inflammatory responses to TLR-4 and TLR-3 agonists through distinct mechanisms related to receptor and HSPG binding respectively, and that these inhibitory effects converged on suppression of JNK and c-Jun activation which are necessary for macrophage activation.
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