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Ma Y, Wang Q, Du S, Luo J, Sun X, Jia B, Ge J, Dong J, Jiang S, Li Z. Multipathway Regulation for Targeted Atherosclerosis Therapy Using Anti-miR-33-Loaded DNA Origami. ACS NANO 2024. [PMID: 38321605 DOI: 10.1021/acsnano.3c10213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
Given the multifactorial pathogenesis of atherosclerosis (AS), a chronic inflammatory disease, combination therapy arises as a compelling approach to effectively address the complex interplay of pathogenic mechanisms for a more desired treatment outcome. Here, we present cRGD/ASOtDON, a nanoformulation based on a self-assembled DNA origami nanostructure for the targeted combination therapy of AS. cRGD/ASOtDON targets αvβ3 integrin receptors overexpressed on pro-inflammatory macrophages and activated endothelial cells in atherosclerotic lesions, alleviates the oxidative stress induced by extracellular and endogenous reactive oxygen species, facilitates the polarization of pro-inflammatory macrophages toward the anti-inflammatory M2 phenotype, and inhibits foam cell formation by promoting cholesterol efflux from macrophages by downregulating miR-33. The antiatherosclerotic efficacy and safety profile of cRGD/ASOtDON, as well as its mechanism of action, were validated in an AS mouse model. cRGD/ASOtDON treatment reversed AS progression and restored normal morphology and tissue homeostasis of the diseased artery. Compared to probucol, a clinical antiatherosclerotic drug with a similar mechanism of action, cRGD/ASOtDON enabled the desired therapeutic outcome at a notably lower dosage. This study demonstrates the benefits of targeted combination therapy in AS management and the potential of self-assembled DNA nanoformulations in addressing multifactorial inflammatory conditions.
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Affiliation(s)
- Yuxuan Ma
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Qi Wang
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Shiyu Du
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Jingwei Luo
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Xiaolei Sun
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Bin Jia
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Jingru Ge
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Jun Dong
- Department of Neurosurgery, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P. R. China
| | - Shuoxing Jiang
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
| | - Zhe Li
- Department of Biomedical Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing, Jiangsu 210023, P. R. China
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Hiroyama S, Matsunaga K, Ito M, Iimori H, Morita I, Nakamura J, Shimosegawa E, Abe K. Evaluation of an Integrin α vβ 3 Radiotracer, [ 18F]F-FPP-RGD 2, for Monitoring Pharmacological Effects of Integrin α v siRNA in the NASH Liver. Nucl Med Mol Imaging 2023; 57:172-179. [PMID: 37483876 PMCID: PMC10359219 DOI: 10.1007/s13139-023-00791-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 01/19/2023] [Accepted: 02/07/2023] [Indexed: 03/09/2023] Open
Abstract
Purpose Integrin αv is a key regulator in the pathophysiology of hepatic fibrosis. In this study, we evaluated the potential utility of an integrin αvβ3 positron emission tomography (PET) radiotracer, 18F-labeled cyclic arginine-glycine-aspartic acid penta-peptide ([18F]F-FPP-RGD2), for detecting hepatic integrin αv and function in nonalcoholic steatohepatitis (NASH) model rats using integrin αv siRNA. Methods NASH model rats were produced by feeding a choline-deficient, low-methionine, high-fat diet for 8 weeks. PET/computerized tomography imaging and quantification of integrin αv protein, serum aspartate aminotransferase, and alanine aminotransferase were performed 1 week after single intravenous injection of integrin αv siRNA. Results Integrin αv siRNA (0.1 and 0.5 mg/kg) dose-dependently decreased hepatic integrin αv protein concentrations in control and NASH model rats. The hepatic mean standard uptake value of [18F]F-FPP-RGD2 was decreased dose-dependently by integrin αv siRNA. The mean standard uptake value was positively correlated with integrin αv protein levels in control and NASH model rats. Serum aspartate aminotransferase and alanine aminotransferase concentrations were also decreased by siRNA injection and correlated with liver integrin αv protein expression levels in NASH model rats. Conclusion This study suggests that [18F]F-FPP-RGD2 PET imaging is a promising radiotracer for monitoring hepatic integrin αv protein levels and hepatic function in NASH pathology.
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Affiliation(s)
- Shuichi Hiroyama
- Biomarker R&D Department, Shionogi & Co., Ltd., 3-1-1 Futaba-Cho, Toyonaka, Osaka 561-0825 Japan
| | - Keiko Matsunaga
- Department of Molecular Imaging in Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Miwa Ito
- Biomarker R&D Department, Shionogi & Co., Ltd., 3-1-1 Futaba-Cho, Toyonaka, Osaka 561-0825 Japan
| | - Hitoshi Iimori
- Laboratory for Advanced Medicine Research, Shionogi & Co., Ltd., Osaka, Japan
| | - Ippei Morita
- Laboratory for Advanced Medicine Research, Shionogi & Co., Ltd., Osaka, Japan
| | - Jun Nakamura
- Laboratory for Advanced Medicine Research, Shionogi & Co., Ltd., Osaka, Japan
| | - Eku Shimosegawa
- Department of Molecular Imaging in Medicine, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Kohji Abe
- Biomarker R&D Department, Shionogi & Co., Ltd., 3-1-1 Futaba-Cho, Toyonaka, Osaka 561-0825 Japan
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Noninvasive photoacoustic computed tomography/ultrasound imaging to identify high-risk atherosclerotic plaques. Eur J Nucl Med Mol Imaging 2022; 49:4601-4615. [DOI: 10.1007/s00259-022-05911-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 07/07/2022] [Indexed: 11/04/2022]
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Yurdagul A. Crosstalk Between Macrophages and Vascular Smooth Muscle Cells in Atherosclerotic Plaque Stability. Arterioscler Thromb Vasc Biol 2022; 42:372-380. [PMID: 35172605 PMCID: PMC8957544 DOI: 10.1161/atvbaha.121.316233] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Most acute cardiovascular events are due to plaque rupture, with atheromas containing large necrotic cores and thin fibrous caps being more susceptible to rupture and lesions with small necrotic cores and thick fibrous caps being more protected from rupture. Atherosclerotic plaques are comprised various extracellular matrix proteins, modified lipoprotein particles, and cells of different origins, that is, vascular cells and leukocytes. Although much has been revealed about the mechanisms that lead to plaque instability, several key areas remain incompletely understood. This In-Focus Review highlights processes related to cellular crosstalk and the role of the tissue microenvironment in determining cell function and plaque stability. Recent advances highlight critical underpinnings of atherosclerotic plaque vulnerability, particularly impairments in the ability of macrophages to clear dead cells and phenotypic switching of vascular smooth muscle cells. However, these processes do not occur in isolation, as crosstalk between macrophages and vascular smooth muscle cells and interactions with their surrounding microenvironment play a significant role in determining plaque stability. Understanding these aspects of cellular crosstalk within an atherosclerotic plaque may shed light on how to modify cell behavior and identify novel approaches to transform rupture-prone atheromas into stable lesions.
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Affiliation(s)
- Arif Yurdagul
- Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences, Shreveport
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5
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Chavda V, Chaurasia B, Deora H, Umana GE. Chronic Kidney disease and stroke: A Bi-directional risk cascade and therapeutic update. BRAIN DISORDERS 2021. [DOI: 10.1016/j.dscb.2021.100017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022] Open
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Sanyour HJ, Li N, Rickel AP, Childs JD, Kinser CN, Hong Z. Membrane cholesterol and substrate stiffness co-ordinate to induce the remodelling of the cytoskeleton and the alteration in the biomechanics of vascular smooth muscle cells. Cardiovasc Res 2019; 115:1369-1380. [PMID: 30395154 PMCID: PMC11268160 DOI: 10.1093/cvr/cvy276] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 06/07/2018] [Accepted: 11/01/2018] [Indexed: 04/10/2024] Open
Abstract
AIMS Cholesterol not only deposits in foam cells at the atherosclerotic plaque, but also plays an important role as a regulator of cell migration in atherogenesis. In addition, the progression of atherosclerosis leads to arterial wall stiffening, and thus altering the micromechanical environment of vascular smooth muscle cells (VSMCs) in vivo. Our studies aim to test the hypothesis that membrane cholesterol and substrate stiffness co-ordinate to regulate VSMCs biomechanics, and thus potentially regulate VSMCs migration and atherosclerotic plaque formation. METHODS AND RESULTS Methyl-β-cyclodextrin was used to manipulate membrane cholesterol content in VSMCs isolated from the descending thoracic aorta of male Sprague-Dawley rats and cultured on Type I collagen-coated polyacrylamide gel substrates with varying stiffness. Atomic force microscopy (AFM) was used to determine VSMCs stiffness and integrin-fibronectin (FN) adhesion. The alignment of submembranous actin filaments was visualized with AFM and confocal microscopy. The constriction force of rat aorta was measured ex vivo using a multi-wire myograph system. Our results demonstrated that cholesterol-depletion and substrate-softening induced a significant decrease in VSMCs stiffness and adhesion to FN, as well as cytoskeletal disorganization. In addition, the contractile force of rat aorta was reduced upon cholesterol-depletion. Cholesterol-enrichment resulted in an increase in stiffness, adhesion to FN, cytoskeletal organization of VSMCs compared with the cholesterol-depleted cells, and enhanced contractile force of rat aortas compared with the cholesterol-depleted vessel rings. CONCLUSION Cell membrane cholesterol and substrate stiffness synergistically affect VSMCs elastic modulus (E-modulus) by regulating the organization of the actin cytoskeleton. Except for the 3.5 kPa gel substrate, cholesterol-depletion decreased VSMCs-FN adhesion force, adhesion loading rate, cytoskeletal orientation, and E-modulus compared with the control VSMCs. Conversely, cholesterol-enrichment significantly increased cytoskeleton orientation, stiffness, and VSMCs-FN cell adhesion force compared with both control and cholesterol-depleted VSMCs on a soft substrate.
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MESH Headings
- Animals
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/pathology
- Aorta, Thoracic/physiopathology
- Atherosclerosis/metabolism
- Atherosclerosis/pathology
- Atherosclerosis/physiopathology
- Biomechanical Phenomena
- Cell Adhesion
- Cell Membrane/metabolism
- Cell Membrane/pathology
- Cells, Cultured
- Cholesterol/metabolism
- Cytoskeleton/metabolism
- Cytoskeleton/pathology
- Elastic Modulus
- Male
- Mechanotransduction, Cellular
- Microscopy, Atomic Force
- Microscopy, Confocal
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Muscle, Smooth, Vascular/physiopathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Rats, Sprague-Dawley
- Stress, Mechanical
- Vascular Stiffness
- Vasoconstriction
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Affiliation(s)
- Hanna J. Sanyour
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Na Li
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Alex P. Rickel
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Josh D. Childs
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Courtney N. Kinser
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Zhongkui Hong
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
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7
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Higashi Y, Gautam S, Delafontaine P, Sukhanov S. IGF-1 and cardiovascular disease. Growth Horm IGF Res 2019; 45:6-16. [PMID: 30735831 PMCID: PMC6504961 DOI: 10.1016/j.ghir.2019.01.002] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 10/17/2018] [Accepted: 01/30/2019] [Indexed: 12/14/2022]
Abstract
Atherosclerosis is an inflammatory arterial pathogenic condition, which leads to ischemic cardiovascular diseases, such as coronary artery disease and myocardial infarction, stroke, and peripheral arterial disease. Atherosclerosis is a multifactorial disorder and its pathophysiology is highly complex. Changes in expression of multiple genes coupled with environmental and lifestyle factors initiate cascades of adverse events involving multiple types of cells (e.g. vascular endothelial cells, smooth muscle cells, and macrophages). IGF-1 is a pleiotropic factor, which is found in the circulation (endocrine IGF-1) and is also produced locally in arteries (endothelial cells and smooth muscle cells). IGF-1 exerts a variety of effects on these cell types in the context of the pathogenesis of atherosclerosis. In fact, there is an increasing body of evidence suggesting that IGF-1 has beneficial effects on the biology of atherosclerosis. This review will discuss recent findings relating to clinical investigations on the relation between IGF-1 and cardiovascular disease and basic research using animal models of atherosclerosis that have elucidated some of the mechanisms underlying atheroprotective effects of IGF-1.
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Affiliation(s)
- Yusuke Higashi
- Department of Medicine, School of Medicine, University of Missouri, Columbia, MO, United States; Harry S. Truman Memorial Veterans' Hospital, Columbia, MO, United States.
| | - Sandeep Gautam
- Department of Medicine, School of Medicine, University of Missouri, Columbia, MO, United States
| | - Patrick Delafontaine
- Department of Medicine, School of Medicine, University of Missouri, Columbia, MO, United States
| | - Sergiy Sukhanov
- Department of Medicine, School of Medicine, University of Missouri, Columbia, MO, United States
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8
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Jiang L, Zhu H, Li Y, Wu X, Wang H, Cheng Z. Detecting Vulnerable Atherosclerotic Plaques by 68Ga-Labeled Divalent Cystine Knot Peptide. Mol Pharm 2019; 16:1350-1357. [PMID: 30742442 DOI: 10.1021/acs.molpharmaceut.8b01291] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Lei Jiang
- Department of Nuclear Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Hong Zhu
- Laboratory of Oral Microbiology, Shanghai Research Institute of Stomatology, Shanghai Key Laboratory of Stomatology, Ninth People’s Hospital, School of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China
| | - Yi Li
- Department of Nuclear Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Xiaodong Wu
- Department of Nuclear Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Huoqiang Wang
- Department of Nuclear Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Zhen Cheng
- Molecular Imaging Program at Stanford (MIPS), Department of Radiology and Bio-X Program, Canary Center at Stanford for Cancer Early Detection, Stanford University, Stanford, California 94305-5484, United States
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9
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Moss AJ, Adamson PD, Newby DE, Dweck MR. Positron emission tomography imaging of coronary atherosclerosis. Future Cardiol 2018; 12:483-96. [PMID: 27322032 PMCID: PMC4926532 DOI: 10.2217/fca-2016-0017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Inflammation has a central role in the progression of coronary atherosclerosis. Recent developments in cardiovascular imaging with the advent of hybrid positron emission tomography have provided a window into the molecular pathophysiology underlying coronary plaque inflammation. Using novel radiotracers targeted at specific cellular pathways, the potential exists to observe inflammation, apoptosis, cellular hypoxia, microcalcification and angiogenesis in vivo. Several clinical studies are now underway assessing the ability of this hybrid imaging modality to inform about atherosclerotic disease activity and the prediction of future cardiovascular risk. A better understanding of the molecular mechanisms governing coronary atherosclerosis may be the first step toward offering patients a more stratified, personalized approach to treatment.
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Affiliation(s)
- Alastair J Moss
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Philip D Adamson
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - David E Newby
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK
| | - Marc R Dweck
- Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UK.,Translation Molecular Imaging Institute, Icahn School of Medicine at Mount-Sinai, NY, USA
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10
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Alaarg A, Pérez-Medina C, Metselaar JM, Nahrendorf M, Fayad ZA, Storm G, Mulder WJM. Applying nanomedicine in maladaptive inflammation and angiogenesis. Adv Drug Deliv Rev 2017; 119:143-158. [PMID: 28506745 PMCID: PMC5682240 DOI: 10.1016/j.addr.2017.05.009] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Revised: 04/12/2017] [Accepted: 05/09/2017] [Indexed: 12/11/2022]
Abstract
Inflammation and angiogenesis drive the development and progression of multiple devastating diseases such as atherosclerosis, cancer, rheumatoid arthritis, and inflammatory bowel disease. Though these diseases have very different phenotypic consequences, they possess several common pathophysiological features in which monocyte recruitment, macrophage polarization, and enhanced vascular permeability play critical roles. Thus, developing rational targeting strategies tailored to the different stages of the journey of monocytes, from bone marrow to local lesions, and their extravasation from the vasculature in diseased tissues will advance nanomedicine. The integration of in vivo imaging uniquely allows studying nanoparticle kinetics, accumulation, clearance, and biological activity, at levels ranging from subcellular to an entire organism, and will shed light on the fate of intravenously administered nanomedicines. We anticipate that convergence of nanomedicines, biomedical engineering, and life sciences will help to advance clinically relevant therapeutics and diagnostic agents for patients with chronic inflammatory diseases.
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Affiliation(s)
- Amr Alaarg
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA; Department of Biomaterials Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands; Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Carlos Pérez-Medina
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Josbert M Metselaar
- Department of Biomaterials Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands; Institute for Experimental Molecular Imaging, University Clinic, Helmholtz Institute for Biomedical Engineering, Aachen, Germany
| | - Matthias Nahrendorf
- Center for Systems Biology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Zahi A Fayad
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Gert Storm
- Department of Biomaterials Science and Technology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands; Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences (UIPS), Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Willem J M Mulder
- Translational and Molecular Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA; Department of Medical Biochemistry, Academic Medical Center, Amsterdam, The Netherlands.
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11
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The arterial microenvironment: the where and why of atherosclerosis. Biochem J 2017; 473:1281-95. [PMID: 27208212 DOI: 10.1042/bj20150844] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 02/15/2016] [Indexed: 12/11/2022]
Abstract
The formation of atherosclerotic plaques in the large and medium sized arteries is classically driven by systemic factors, such as elevated cholesterol and blood pressure. However, work over the past several decades has established that atherosclerotic plaque development involves a complex coordination of both systemic and local cues that ultimately determine where plaques form and how plaques progress. Although current therapeutics for atherosclerotic cardiovascular disease primarily target the systemic risk factors, a large array of studies suggest that the local microenvironment, including arterial mechanics, matrix remodelling and lipid deposition, plays a vital role in regulating the local susceptibility to plaque development through the regulation of vascular cell function. Additionally, these microenvironmental stimuli are capable of tuning other aspects of the microenvironment through collective adaptation. In this review, we will discuss the components of the arterial microenvironment, how these components cross-talk to shape the local microenvironment, and the effect of microenvironmental stimuli on vascular cell function during atherosclerotic plaque formation.
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12
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Integrin signaling in atherosclerosis. Cell Mol Life Sci 2017; 74:2263-2282. [PMID: 28246700 DOI: 10.1007/s00018-017-2490-4] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/24/2017] [Accepted: 02/15/2017] [Indexed: 02/07/2023]
Abstract
Atherosclerosis, a chronic lipid-driven inflammatory disease affecting large arteries, represents the primary cause of cardiovascular disease in the world. The local remodeling of the vessel intima during atherosclerosis involves the modulation of vascular cell phenotype, alteration of cell migration and proliferation, and propagation of local extracellular matrix remodeling. All of these responses represent targets of the integrin family of cell adhesion receptors. As such, alterations in integrin signaling affect multiple aspects of atherosclerosis, from the earliest induction of inflammation to the development of advanced fibrotic plaques. Integrin signaling has been shown to regulate endothelial phenotype, facilitate leukocyte homing, affect leukocyte function, and drive smooth muscle fibroproliferative remodeling. In addition, integrin signaling in platelets contributes to the thrombotic complications that typically drive the clinical manifestation of cardiovascular disease. In this review, we examine the current literature on integrin regulation of atherosclerotic plaque development and the suitability of integrins as potential therapeutic targets to limit cardiovascular disease and its complications.
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13
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Maile LA, Busby WH, Xi G, Gollahan KP, Flowers W, Gafbacik N, Gafbacik S, Stewart K, Merricks EP, Nichols TC, Bellinger DA, Clemmons DR. An anti-αVβ3 antibody inhibits coronary artery atherosclerosis in diabetic pigs. Atherosclerosis 2017; 258:40-50. [PMID: 28189040 DOI: 10.1016/j.atherosclerosis.2017.01.030] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 01/19/2017] [Accepted: 01/25/2017] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND AIMS Diabetes is a major risk factor for the development of atherosclerosis. Hyperglycemia stimulates vascular smooth muscle cells (VSMC) to secrete ligands that bind to the αVβ3 integrin, a receptor that regulates VSMC proliferation and migration. This study determined whether an antibody that had previously been shown to block αVβ3 activation and to inhibit VSMC proliferation and migration in vitro, inhibited the development of atherosclerosis in diabetic pigs. METHODS Twenty diabetic pigs were maintained on a high fat diet for 22 weeks. Ten received injections of anti-β3 F(ab)2 and ten received control F(ab)2 for 18 weeks. RESULTS The active antibody group showed reduction of atherosclerosis of 91 ± 9% in the left main, 71 ± 11%, in left anterior descending, 80 ± 10.2% in circumflex, and 76 ± 25% in right coronary artery, (p < 0.01 compared to lesions areas from corresponding control treated arteries). There were significant reductions in both cell number and extracellular matrix. Histologic analysis showed neointimal hyperplasia with macrophage infiltration, calcifications and cholesterol clefts. Antibody treatment significantly reduced number of macrophages contained within lesions, suggesting that this change contributed to the decrease in lesion cellularity. Analysis of the biochemical changes within the femoral arteries that received the active antibody showed a 46 ± 12% (p < 0.05) reduction in the tyrosine phosphorylation of the β3 subunit of αVβ3 and a 40 ± 14% (p < 0.05) reduction in MAP kinase activation. CONCLUSIONS Blocking ligand binding to the αVβ3 integrin inhibits its activation and attenuates increased VSMC proliferation that is induced by chronic hyperglycemia. These changes result in significant decreases in atherosclerotic lesion size in the coronary arteries. The results suggest that this approach may have efficacy in treating the proliferative phase of atherosclerosis in patients with diabetes.
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Affiliation(s)
- L A Maile
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - W H Busby
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - G Xi
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - K P Gollahan
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - W Flowers
- Department of Animal Science, NC State University, Raleigh, NC, USA
| | - N Gafbacik
- Department of Animal Science, NC State University, Raleigh, NC, USA
| | - S Gafbacik
- Department of Animal Science, NC State University, Raleigh, NC, USA
| | - K Stewart
- Department of Animal Science, NC State University, Raleigh, NC, USA
| | - E P Merricks
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - T C Nichols
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - D A Bellinger
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA
| | - D R Clemmons
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC, USA.
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15
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Abstract
Chronic kidney disease (CKD) is a lethal and rapidly increasing burden on society. Despite this, there are relatively few therapies in development for the treatment of CKD. Several recent costly phase 3 trials have failed to provide improved renal outcomes, diminishing interest in pharmaceutical investment. Furthermore, poor patient, physician, and payer awareness of CKD as a diagnosis has contributed to slow trial enrollment and successful implementation of these trials. Nevertheless, several therapeutics remain in development for the treatment of CKD, including mineralocorticoid-receptor antagonists, sodium/glucose cotransporter 2 inhibitors, anti-inflammatory drugs, and drugs that mitigate oxidative injury. Success of future CKD therapeutic trials will depend not only on improved understanding of disease pathogenesis, but also on improved trial enrollment rates, through increasing awareness of this disease by the public, policy makers, and the greater medical community.
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Affiliation(s)
- Matthew D Breyer
- Biotechnology Discovery Research, Eli Lilly and Company, Indianapolis, IN.
| | - Katalin Susztak
- Renal Electrolyte and Hypertension Division, Department of Medicine, University of Pennsylvania, Philadelphia, PA
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Rational design of a protein that binds integrin αvβ3 outside the ligand binding site. Nat Commun 2016; 7:11675. [PMID: 27241473 PMCID: PMC4895024 DOI: 10.1038/ncomms11675] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2015] [Accepted: 04/19/2016] [Indexed: 12/28/2022] Open
Abstract
Integrin αvβ3 expression is altered in various diseases and has been proposed as a drug target. Here we use a rational design approach to develop a therapeutic protein, which we call ProAgio, that binds to integrin αvβ3 outside the classical ligand-binding site. We show ProAgio induces apoptosis of integrin αvβ3-expressing cells by recruiting and activating caspase 8 to the cytoplasmic domain of integrin αvβ3. ProAgio also has anti-angiogenic activity and strongly inhibits growth of tumour xenografts, but does not affect the established vasculature. Toxicity analyses demonstrate that ProAgio is not toxic to mice. Our study reports a new integrin-targeting agent with a unique mechanism of action, and provides a template for the development of integrin-targeting therapeutics. Integrins are transmembrane proteins that have important roles in cell adhesion and signalling. Here the authors design a therapeutic protein that binds integrin αvβ3, has anti-angiogenic activity, and reduces tumour growth in xenograft models, while being seemingly well tolerated.
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Abstract
Chronic kidney disease (CKD) represents a leading cause of death in the United States. There is no cure for this disease, with current treatment strategies relying on blood pressure control through blockade of the renin-angiotensin system. Such approaches only delay the development of end-stage kidney disease and can be associated with serious side effects. Recent identification of several novel mechanisms contributing to CKD development - including vascular changes, loss of podocytes and renal epithelial cells, matrix deposition, inflammation and metabolic dysregulation - has revealed new potential therapeutic approaches for CKD. This Review assesses emerging strategies and agents for CKD treatment, highlighting the associated challenges in their clinical development.
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18
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Misra A, Sheikh AQ, Kumar A, Luo J, Zhang J, Hinton RB, Smoot L, Kaplan P, Urban Z, Qyang Y, Tellides G, Greif DM. Integrin β3 inhibition is a therapeutic strategy for supravalvular aortic stenosis. J Exp Med 2016; 213:451-63. [PMID: 26858344 PMCID: PMC4813675 DOI: 10.1084/jem.20150688] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 01/08/2016] [Indexed: 02/03/2023] Open
Abstract
Misra et al. elucidate the origin of smooth muscle cells involved in supravalvular aortic stenosis and identify the integrin β3 pathway as a therapeutic target in this disease. The aorta is the largest artery in the body, yet processes underlying aortic pathology are poorly understood. The arterial media consists of circumferential layers of elastic lamellae and smooth muscle cells (SMCs), and many arterial diseases are characterized by defective lamellae and excess SMCs; however, a mechanism linking these pathological features is lacking. In this study, we use lineage and genetic analysis, pharmacological inhibition, explant cultures, and induced pluripotent stem cells (iPSCs) to investigate supravalvular aortic stenosis (SVAS) patients and/or elastin mutant mice that model SVAS. These experiments demonstrate that multiple preexisting SMCs give rise to excess aortic SMCs in elastin mutants, and these SMCs are hyperproliferative and dedifferentiated. In addition, SVAS iPSC-derived SMCs and the aortic media of elastin mutant mice and SVAS patients have enhanced integrin β3 levels, activation, and downstream signaling, resulting in SMC misalignment and hyperproliferation. Reduced β3 gene dosage in elastin-null mice mitigates pathological aortic muscularization, SMC misorientation, and lumen loss and extends survival, which is unprecedented. Finally, pharmacological β3 inhibition in elastin mutant mice and explants attenuates aortic hypermuscularization and stenosis. Thus, integrin β3–mediated signaling in SMCs links elastin deficiency and pathological stenosis, and inhibiting this pathway is an attractive therapeutic strategy for SVAS.
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Affiliation(s)
- Ashish Misra
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
| | - Abdul Q Sheikh
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
| | - Abhishek Kumar
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
| | - Jiesi Luo
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
| | - Jiasheng Zhang
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
| | - Robert B Hinton
- Division of Cardiology, The Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229
| | - Leslie Smoot
- Department of Cardiology, Boston Children's Hospital, Boston, MA 02115
| | - Paige Kaplan
- Section of Metabolic Diseases, Children's Hospital of Pennsylvania, Philadelphia, PA 19104
| | - Zsolt Urban
- Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261
| | - Yibing Qyang
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
| | - George Tellides
- Department of Surgery, School of Medicine, Yale University, New Haven, CT 06511
| | - Daniel M Greif
- Yale Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, School of Medicine, Yale University, New Haven, CT 06511
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19
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Xi G, Shen X, Wai C, Vilas CK, Clemmons DR. Hyperglycemia stimulates p62/PKCζ interaction, which mediates NF-κB activation, increased Nox4 expression, and inflammatory cytokine activation in vascular smooth muscle. FASEB J 2015; 29:4772-82. [PMID: 26231202 DOI: 10.1096/fj.15-275453] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 07/20/2015] [Indexed: 12/20/2022]
Abstract
Hyperglycemia leads to vascular smooth muscle cell (VSMC) dedifferentiation and enhances responses to IGF-I. Prior studies showed that hyperglycemia stimulated NADPH oxidase 4 (Nox4) synthesis, and IGF-I facilitated its recruitment to a signaling complex where it oxidized src, leading to AKT and MAPK activation. To determine the mechanism that led to these changes, we analyzed the roles of p62 (sequestrosome1) and PKCζ. Hyperglycemia induced a 4.9 ± 1.0-fold increase in p62/PKCζ association, and disruption of PKCζ/p62 using a peptide inhibitor or p62 knockdown reduced PKCζ activation (78 ± 6%). 3-Phosphoinoside-dependent protein kinase 1 was also recruited to the p62 complex and directly phosphorylated PKCζ, leading to its activation (3.1 ± 0.4-fold). Subsequently, activated PKCζ phosphorylated p65 rel, which led to increased Nox4 synthesis. Studies in diabetic mice confirmed these findings (6.0 ± 0.4-fold increase in p62/PKCζ) and their disruption of attenuated Nox4 synthesis (76 ± 9% reduction). PKCζ/p62 activation stimulated inflammatory cytokine production and enhanced IGF-I-stimulated VSMC proliferation. These results define the molecular mechanism by which PKCζ is activated in response to hyperglycemia and suggest that this could be a mechanism by which other stimuli such as cytokines or metabolic stress function to stimulate NF-κB activation, thereby altering VSMC sensitivity to IGF-I.
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Affiliation(s)
- Gang Xi
- *Department of Medicine, University of North Carolina, School of Medicine, Chapel Hill, North Carolina, USA; and College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China
| | - Xinchun Shen
- *Department of Medicine, University of North Carolina, School of Medicine, Chapel Hill, North Carolina, USA; and College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China
| | - Christine Wai
- *Department of Medicine, University of North Carolina, School of Medicine, Chapel Hill, North Carolina, USA; and College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China
| | - Caroline K Vilas
- *Department of Medicine, University of North Carolina, School of Medicine, Chapel Hill, North Carolina, USA; and College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China
| | - David R Clemmons
- *Department of Medicine, University of North Carolina, School of Medicine, Chapel Hill, North Carolina, USA; and College of Food Science and Engineering, Nanjing University of Finance and Economics, Nanjing, China
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20
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Chen J, Green J, Yurdagul A, Albert P, McInnis MC, Orr AW. αvβ3 Integrins Mediate Flow-Induced NF-κB Activation, Proinflammatory Gene Expression, and Early Atherogenic Inflammation. THE AMERICAN JOURNAL OF PATHOLOGY 2015. [PMID: 26212910 DOI: 10.1016/j.ajpath.2015.05.013] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Endothelial cell interactions with transitional matrix proteins, such as fibronectin, occur early during atherogenesis and regulate shear stress-induced endothelial cell activation. Multiple endothelial cell integrins bind transitional matrix proteins, including α5β1, αvβ3, and αvβ5. However, the role these integrins play in mediating shear stress-induced endothelial cell activation remains unclear. Therefore, we sought to elucidate which integrin heterodimers mediate shear stress-induced endothelial cell activation and early atherogenesis. We now show that inhibiting αvβ3 integrins (S247, siRNA), but not α5β1 or αvβ5, blunts shear stress-induced proinflammatory signaling (NF-κB, p21-activated kinase) and gene expression (ICAM1, VCAM1). Importantly, inhibiting αvβ3 did not affect cytokine-induced proinflammatory responses or inhibit all shear stress-induced signaling, because Akt, endothelial nitric oxide synthase, and extracellular regulated kinase activation remained intact. Furthermore, inhibiting αv integrins (S247), but not α5 (ATN-161), in atherosclerosis-prone apolipoprotein E knockout mice significantly reduced vascular remodeling after acute induction of disturbed flow. S247 treatment similarly reduced early diet-induced atherosclerotic plaque formation associated with both diminished inflammation (expression of vascular cell adhesion molecule 1, plaque macrophage content) and reduced smooth muscle incorporation. Inducible, endothelial cell-specific αv integrin deletion similarly blunted inflammation in models of disturbed flow and diet-induced atherogenesis but did not affect smooth muscle incorporation. Our studies identify αvβ3 as the primary integrin heterodimer mediating shear stress-induced proinflammatory responses and as a key contributor to early atherogenic inflammation.
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Affiliation(s)
- Jie Chen
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana
| | - Jonette Green
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana
| | - Arif Yurdagul
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana; Department of Cell Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, Louisiana
| | - Patrick Albert
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana
| | - Marshall C McInnis
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana
| | - A Wayne Orr
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana.
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21
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22
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Menendez-Castro C, Cordasic N, Neureiter D, Amann K, Marek I, Volkert G, Stintzing S, Jahn A, Rascher W, Hilgers KF, Hartner A. Under-expression of α8 integrin aggravates experimental atherosclerosis. J Pathol 2015; 236:5-16. [PMID: 25511181 DOI: 10.1002/path.4501] [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: 08/11/2014] [Revised: 11/28/2014] [Accepted: 12/09/2014] [Indexed: 11/08/2022]
Abstract
Integrins play an important role in vascular biology. The α8 integrin chain attenuates smooth muscle cell migration but its functional role in the development of atherosclerosis is unclear. Therefore, we studied the contribution of α8 integrin to atherosclerosis and vascular remodelling. We hypothesized that α8 integrin expression is reduced in atherosclerotic lesions, and that its under-expression leads to a more severe course of atherosclerosis. α8 Integrin was detected by immunohistochemistry and qPCR and α8 integrin-deficient mice were used to induce two models of atherosclerotic lesions. First, ligation of the carotid artery led to medial thickening and neointima formation, which was quantified in carotid cross-sections. Second, after crossing into ApoE-deficient mice, the formation of advanced vascular lesions with atherosclerotic plaques was quantified in aortic en face preparations stained with Sudan IV. Parameters of renal physiology and histopathology were assessed: α8 integrin was detected in the media of human and murine vascular tissue and was down-regulated in arteries with advanced atherosclerotic lesions. In α8 integrin-deficient mice (α8(-/-) ) as well as α8(+/-) and α8(+/+) littermates, carotid artery ligation increased media:lumen ratios in all genotypes, with higher values in ligated α8(-/-) and α8(+/-) compared to ligated α8(+/+) animals. Carotid artery ligation increased smooth muscle cell number in the media of α8(+/+) mice and, more prominently, of α8(-/-) or α8(+/-) mice. On an ApoE(-/-) background, α8(+/-) and α8(-/-) mice developed more atherosclerotic plaques than α8(+/+) mice. α8 Integrin expression was reduced in α8(+/-) animals. Renal damage with increased serum creatinine and glomerulosclerosis was detected in α8(-/-) mice only. Thus, under-expression of α8 integrin aggravates vascular lesions, while a complete loss of α8 integrin results in reduced renal mass and additional renal disease in the presence of generalized atherosclerosis. Our data support the hypothesis that integrin α8β1 has a protective role in arterial remodelling and atherosclerosis.
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Affiliation(s)
- Carlos Menendez-Castro
- Department of Paediatrics and Adolescent Medicine, University of Erlangen-Nürnberg, Germany
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23
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Maile LA, Busby WH, Gollahon KA, Flowers W, Garbacik N, Garbacik S, Stewart K, Nichols T, Bellinger D, Patel A, Dunbar P, Medlin M, Clemmons D. Blocking ligand occupancy of the αVβ3 integrin inhibits the development of nephropathy in diabetic pigs. Endocrinology 2014; 155:4665-75. [PMID: 25171599 PMCID: PMC4239428 DOI: 10.1210/en.2014-1318] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hyperglycemia stimulates secretion of αVβ3 ligands from vascular cells, including endothelial cells, resulting in activation of the αVβ3 integrin. This study determined whether blocking ligand occupancy of αVβ3 would inhibit the development of diabetic nephropathy. Ten diabetic pigs received an F(ab)2 fragment of an antibody directed against the extracellular domain of the β3-subunit, and 10 received a control IgG F(ab)2 for 18 weeks. Nondiabetic pigs excreted 115 ± 50 μg of protein/mg creatinine compared with control F(ab)2-treated diabetic animals (218 ± 57 μg/mg), whereas diabetic animals treated with the anti-β3 F(ab)2 excreted 119 ± 55 μg/mg (P < .05). Mesangial volume/glomerular volume increased to 21 ± 2.4% in control-treated diabetic animals compared with 14 ± 2.8% (P < .01) in animals treated with active antibody. Diabetic animals treated with control F(ab)2 had significantly less glomerular podocin staining compared with nondiabetic animals, and this decrease was attenuated by treatment with anti-β3 F(ab)2. Glomerular basement membrane thickness was increased in the control, F(ab)2-treated diabetic animals (212 ± 14 nm) compared with nondiabetic animals (170 ± 8.8 nm), but it was unchanged (159.9 ± 16.4 nm) in animals receiving anti-β3 F(ab)2. Podocyte foot process width was greater in control, F(ab)2-treated, animals (502 ± 34 nm) compared with animals treated with the anti-β3 F(ab)2 (357 ± 47 nm, P < .05). Renal β3 tyrosine phosphorylation decreased from 13 934 ± 6437 to 6730 ± 1524 (P < .01) scanning units in the anti-β3-treated group. We conclude that administration of an antibody that inhibits activation of the β3-subunit of αVβ3 that is induced by hyperglycemia attenuates proteinuria and early histologic changes of diabetic nephropathy, suggesting that it may have utility in preventing the progression of this disease complication.
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Affiliation(s)
- Laura A Maile
- Department of Medicine (L.A.M., W.H.B., K.A.G., T.N., D.B., A.P., P.D., M.M., D.C.), University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599; and Department of Animal Science (W.F., N.G., S.G., K.S.), North Carolina State University, Raleigh, North Carolina 27695
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24
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Van Agthoven JF, Xiong JP, Alonso JL, Rui X, Adair BD, Goodman SL, Arnaout MA. Structural basis for pure antagonism of integrin αVβ3 by a high-affinity form of fibronectin. Nat Struct Mol Biol 2014; 21:383-8. [PMID: 24658351 PMCID: PMC4012256 DOI: 10.1038/nsmb.2797] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 02/24/2014] [Indexed: 01/07/2023]
Abstract
Integrins are important therapeutic targets. However, current RGD-based anti-integrin drugs are also partial agonists, inducing conformational changes that trigger potentially fatal immune reactions and paradoxical cell adhesion. Here we describe the first crystal structure of αVβ3 bound to a physiologic ligand, the tenth type III RGD domain of wild-type fibronectin (wtFN10), or to a high-affinity mutant (hFN10) shown here to act as a pure antagonist. Comparison of these structures revealed a central π-π interaction between Trp1496 in the RGD-containing loop of hFN10 and Tyr122 of the β3 subunit that blocked conformational changes triggered by wtFN10 and trapped hFN10-bound αVβ3 in an inactive conformation. Removing the Trp1496 or Tyr122 side chains or reorienting Trp1496 away from Tyr122 converted hFN10 into a partial agonist. These findings offer new insights into the mechanism of integrin activation and a basis for the design of RGD-based pure antagonists.
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Affiliation(s)
- Johannes F. Van Agthoven
- Structural Biology Program, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129
| | - Jian-Ping Xiong
- Structural Biology Program, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129
| | - José Luis Alonso
- Leukocyte Biology & Inflammation Program, Department of Medicine, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129
| | - Xianliang Rui
- Leukocyte Biology & Inflammation Program, Department of Medicine, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129
| | - Brian D. Adair
- Structural Biology Program, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129
| | - Simon L. Goodman
- Harvard Medical School, Global Research and Early Development, Translational Innovation platform, Oncology, Merck KGaA, Darmstadt 64271, Germany
| | - M. Amin Arnaout
- Structural Biology Program, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129,Leukocyte Biology & Inflammation Program, Department of Medicine, Massachusetts General Hospital, 149 13th Street, Charlestown, MA 02129
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25
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Okada Y, Nishikawa JI, Semma M, Ichikawa A. Role of lipid raft components and actin cytoskeleton in fibronectin-binding, surface expression, and de novo synthesis of integrin subunits in PGE2- or 8-Br-cAMP-stimulated mastocytoma P-815 cells. Biochem Pharmacol 2014; 88:364-71. [PMID: 24518258 DOI: 10.1016/j.bcp.2014.01.039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 02/02/2023]
Abstract
Integrins are heterodimeric adhesion receptors essential for adhesion of non-adherent cells to extracellular ligands such as extracellular matrix components. The affinity of integrins for ligands is regulated through a process termed integrin activation and de novo synthesis. Integrin activation is regulated by lipid raft components and the actin structure. However, there is little information on the relationship between integrin activation and its de novo synthesis. Cancerous mouse mast cells, mastocytoma P-815 cells (P-815 cells) are known to bind to fibronectin through de novo synthesis of integrin subtypes by prostaglandin (PG) E2 stimulation. The purpose of this study was to clarify the relationship between lipid raft components and the actin cytoskeleton, and PGE2-induced P-815 cells adhesion to fibronectin and the increase in surface expression and mRNA and protein levels of αvβ3 and αIIbβ3 integrins. Cholesterol inhibitor 6-O-α-maltosyl-β cyclodextrin, glycosylphosphatidylinositol-anchored proteins inhibitor phosphatidylinositol-specific phospholipase C and actin inhibitor cytochalasin D inhibited PGE2-induced cell adhesion to fibronectin, but did not regulate the surface expression and mRNA and protein levels of αv and αIIb, and β3 integrin subunits. In addition, inhibitor of integrin modulate protein CD47 had no effect on PGE2- and 8-Br-cAMP-induced cell adhesion. These results suggest that lipid raft components and the actin cytoskeleton are directly involved in increasing of adhesion activity of integrin αIIb, αv and β3 subunits to fibronectin but not in stimulating of de novo synthesis of them in PGE2-stimulated P-815 cells. The modulation of lipid rafts and the actin structure is essential for P-815 cells adhesion to fibronectin.
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Affiliation(s)
- Yasuyo Okada
- Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Institute for Biosciences, Mukogawa Women's University, 11-68 Koshien-Kyubancho, Nishinomiya-shi, Hyogo 663-8179, Japan
| | - Jyun-ichi Nishikawa
- Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Institute for Biosciences, Mukogawa Women's University, 11-68 Koshien-Kyubancho, Nishinomiya-shi, Hyogo 663-8179, Japan
| | - Masanori Semma
- Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Institute for Biosciences, Mukogawa Women's University, 11-68 Koshien-Kyubancho, Nishinomiya-shi, Hyogo 663-8179, Japan
| | - Atsushi Ichikawa
- Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Institute for Biosciences, Mukogawa Women's University, 11-68 Koshien-Kyubancho, Nishinomiya-shi, Hyogo 663-8179, Japan.
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26
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Maile LA, Gollahon K, Wai C, Dunbar P, Busby W, Clemmons D. Blocking αVβ3 integrin ligand occupancy inhibits the progression of albuminuria in diabetic rats. J Diabetes Res 2014; 2014:421827. [PMID: 25389530 PMCID: PMC4217341 DOI: 10.1155/2014/421827] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 10/07/2014] [Indexed: 12/18/2022] Open
Abstract
This study determined if blocking ligand occupancy of the αVβ3 integrin could inhibit the pathophysiologic changes that occur in the early stages of diabetic nephropathy (DN). Diabetic rats were treated with either vehicle or a monoclonal antibody that binds the β3 subunit of the αVβ3 integrin. After 4 weeks of diabetes the urinary albumin to creatinine ratio (UACR) increased in both diabetic animals that subsequently received vehicle and in the animals that subsequently received the anti-β3 antibody compared with control nondiabetic rats. After 8 weeks of treatment the UACR continued to rise in the vehicle-treated rats; however it returned to levels comparable to control nondiabetic rats in rats treated with the anti-β3 antibody. Treatment with the antibody prevented the increase of several profibrotic proteins that have been implicated in the development of DN. Diabetes was associated with an increase in phosphorylation of the β3 subunit in kidney homogenates from diabetic animals, but this was prevented by the antibody treatment. This study demonstrates that, when administered after establishment of early pathophysiologic changes in renal function, the anti-β3 antibody reversed the effects of diabetes normalizing albuminuria and profibrotic proteins in the kidney to the levels observed in nondiabetic control animals.
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Affiliation(s)
- Laura A. Maile
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC 27599, USA
- Vascular Pharmaceuticals, Inc., 510 Meadowmont Village Circle, Suite 283, Chapel Hill, NC 27517, USA
- *Laura A. Maile:
| | - Katherine Gollahon
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC 27599, USA
| | - Christine Wai
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC 27599, USA
| | - Paul Dunbar
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC 27599, USA
| | - Walker Busby
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC 27599, USA
| | - David Clemmons
- Department of Medicine, UNC School of Medicine, Chapel Hill, NC 27599, USA
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Cam A, Sivaguru M, Gonzalez de Mejia E. Endocytic mechanism of internalization of dietary peptide lunasin into macrophages in inflammatory condition associated with cardiovascular disease. PLoS One 2013; 8:e72115. [PMID: 24039740 PMCID: PMC3764169 DOI: 10.1371/journal.pone.0072115] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2013] [Accepted: 07/03/2013] [Indexed: 12/25/2022] Open
Abstract
Cardiovascular disease (CVD) is the leading cause of death in the United States. Diet influences risk factors associated with CVD and atherosclerosis, a major vascular disease that arises from inflammation. Lunasin, a peptide derived from plant foods such as soybeans, contains a unique Arg-Gly-Asp cell-adhesion motif and inhibits the pathways involved in the inflammatory cascade. The objective was to determine the mechanism by which lunasin is internalized into human THP-1 macrophages, investigate the expression of endocytic membrane proteins in inflammatory conditions and to identify the pathways involved. While lipopolysaccharide (10 nM), vitronectin (130 nM) and a combination of these two molecules enhanced lunasin uptake and increased basal αVβ3 integrin expression, lunasin reduced αVβ3 expression by 25.5, 26.8 and 49.2%, respectively. The pretreatment of cells with brefeldin A (71 µM), an inhibitor of protein trafficking, inhibited lunasin internalization by up to 99.8%. Lunasin increased caveolin-1 expression by up to 204.8%, but did not modulate clathrin. The pretreatment of macrophages with nystatin (54 µM), an inhibitor of caveolae-dependent endocytosis, reduced lunasin internalization. The presence of amantadine (1 mM) and amiloride (1 mM), inhibitors of clathrin-mediated endocytosis and macropinocytosis, abolished lunasin cell entry. Lunasin elicited a transient reduction in intracellular levels of Ca2+ in LPS-induced macrophages. The results suggest that internalization of lunasin into macrophages is amplified in inflammatory conditions and is primarily mediated by endocytic mechanisms that involve integrin signaling, clathrin-coated structures and macropinosomes. Lunasin may be responsible for attenuation of CVD risk factors by interacting with pathways involved in endocytosis and inflammation.
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Affiliation(s)
- Anthony Cam
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Mayandi Sivaguru
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Elvira Gonzalez de Mejia
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- * E-mail:
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28
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Rosas E, Sobenin I, Orekhov A, Edelman ER, Balcells M. Importance of receptor-targeted systems in the battle against atherosclerosis. Curr Pharm Des 2013; 19:5897-903. [PMID: 23438961 PMCID: PMC4637971 DOI: 10.2174/1381612811319330010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 02/14/2013] [Indexed: 11/22/2022]
Abstract
Atherosclerosis is the leading cause of death in the Western World and has been for decades a field of intense research. Yet, while there is a rich and diverse literature describing in detail the players and mechanisms involved in this complex disease in cell and animal models, we remain today with virtually no reliable markers for early diagnosis and targeted treatments options. This review is centered upon the latter. We summarize the latest studies focused on detecting endothelial dysfunction during the early stages of atherosclerosis, when the disease is asymptomatic and describe strategies recently proposed to image and target advanced plaque.
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Affiliation(s)
- Elisabet Rosas
- Massachusetts Institute of Technology, Harvard-MIT Biomedical Engineering Center, 77 Massachusetts Avenue, E25-438, Cambridge, MA 02139, US.
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29
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Molecular Targeting of Imaging and Drug Delivery Probes in Atherosclerosis. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 2013. [DOI: 10.1016/b978-0-12-417150-3.00008-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Cam A, de Mejia EG. RGD-peptide lunasin inhibits Akt-mediated NF-κB activation in human macrophages through interaction with the αVβ3 integrin. Mol Nutr Food Res 2012; 56:1569-81. [PMID: 22945510 DOI: 10.1002/mnfr.201200301] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2012] [Revised: 06/14/2012] [Accepted: 06/19/2012] [Indexed: 01/22/2023]
Abstract
SCOPE Cardiovascular disease is the leading cause of mortality in the United States and regulation of aberrant macrophage activity under inflammatory conditions is critical for its prevention. The objective was to determine the effect of lunasin on the inhibition of Akt-mediated activation of nuclear factor-kappa B (NF-κB)-dependent markers of inflammation and to characterize the physical interaction of lunasin with the αVβ3 integrin receptor in lipopolysaccharide (LPS)-induced human THP-1 macrophages. METHODS AND RESULTS The effect of lunasin was evaluated in vitro in LPS-induced THP-1 human macrophages using immunoassays, co-immunoprecipitation (Co-IP), and fluorescence confocal microscopy. Lunasin (50 μM) reduced cyclooxygenase-2, inducible nitric oxide synthase, and NO levels by 57.9, 64.5, and 76.2%, respectively, and inhibited the activation of phosphorylated Akt and NF-κB p65 by 59.5 and 74.5%, respectively. Lunasin (50 μM) reduced exogenous release of prostaglandin E(2) and tumor necrosis factor-α by 92.5 and 94.9%, respectively. Vitronectin (10 μg/mL), an integrin ligand, increased expression of proinflammatory markers, whereas lunasin (50 μM) attenuated them. Co-IP of lunasin-treated cells confirmed direct interaction with αVβ3 integrin and LC/MS/MS verified its identity. Lunasin was detected within intracellular vesicles and reduced total αVβ3 intensity as observed by fluorescence microscopy. CONCLUSION Lunasin inhibited αVβ3 integrin-mediated proinflammatory markers and downregulated Akt-mediated NF-κB pathways through interaction with αVβ3 integrin.
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Affiliation(s)
- Anthony Cam
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 1201 West Gregory Drive, Urbana, IL 61801, USA
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Insulin-like growth factor (IGF) binding protein 2 functions coordinately with receptor protein tyrosine phosphatase β and the IGF-I receptor to regulate IGF-I-stimulated signaling. Mol Cell Biol 2012; 32:4116-30. [PMID: 22869525 DOI: 10.1128/mcb.01011-12] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Insulin-like growth factor I (IGF-I) is a mitogen for vascular smooth muscle cells (VSMC) and has been implicated in the development and progression of atherosclerosis. IGF binding proteins (IGFBPs) modify IGF-I actions independently of IGF binding, but a receptor-based mechanism by which they function has not been elucidated. We investigated the role of IGFBP-2 and receptor protein tyrosine phosphatase β (RPTPβ) in regulating IGF-I signaling and cellular proliferation. IGFBP-2 bound RPTPβ, which led to its dimerization and inactivation. This enhanced PTEN tyrosine phosphorylation and inhibited PTEN activity. Utilization of substrate trapping and phosphatase-dead mutants showed that RPTPβ bound specifically to PTEN and dephosphorylated it. IGFBP-2 knockdown led to decreased PTEN tyrosine phosphorylation and decreased AKT Ser473 activation. IGFBP-2 enhanced IGF-I-stimulated VSMC migration and proliferation. Analysis of aortas obtained from IGFBP-2(-/-) mice showed that RPTPβ was activated, and this was associated with inhibition of IGF-I stimulated AKT Ser473 phosphorylation and VSMC proliferation. These changes were rescued following administration of IGFBP-2. These findings present a novel mechanism for coordinate regulation of IGFBP-2 and IGF-I signaling functions that lead to stimulation of VSMC proliferation. The results have important implications for understanding how IGFBPs modulate the cellular response to IGF-I.
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Yuan Z, Liao Y, Tian G, Li H, Jia Y, Zhang H, Tan Z, Li X, Deng W, Liu K, Zhang Y. Panax notoginseng saponins inhibit Zymosan A induced atherosclerosis by suppressing integrin expression, FAK activation and NF-κB translocation. JOURNAL OF ETHNOPHARMACOLOGY 2011; 138:150-155. [PMID: 21924337 DOI: 10.1016/j.jep.2011.08.066] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 08/25/2011] [Accepted: 08/30/2011] [Indexed: 05/31/2023]
Abstract
ETHNOPHARMACOLOGICAL SIGNIFICANCE Panax notoginseng saponins (PNS) are ingredients extracted from traditional Chinese medicinal herb Panax notoginseng. It has been demonstrated that PNS have extensive effects on the cardiovascular system, including inhibition of platelet aggregation, increasing blood flow, improving left ventricular diastolic function in hypertensive patients and anti-inflammatory effect. AIM OF STUDY Recent researches indicated that PNS administration inhibited foam cells' formation. The present study was designed to study the effects of PNS on atherogenesis and to explore the relevant molecular mechanisms. MATERIALS AND METHODS The Zymosan A induced atherosclerosis models were used to investigate the anti-atherosclerosis effects of PNS. The integrin express array was used to check the changes of integrins. The foam cell formation was observed with transmission electron microscope. The effect of PNS on phosphorylation of FAK on threonine 397 and protein level of NF-κB was also evaluated in vitro. RESULTS PNS treated rats had less plaque spots on the aortas compared with Zym induced group. The formation of foam cell was inhibited by PNS. Compared with Zym treated group, the expression of most integrin families decreased except Itgav and Itgb2 after PNS treatment. PNS inhibited phosphorylation of FAK on threonine 397 and translocation of NF-κB. CONCLUSION High fat diet together with Zym induces atherogenesis of rat. PNS inhibits zymosan A induced atherogenesis by suppressing FAK phosphorylation, integrins expression and NF-κB translocation.
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Affiliation(s)
- Zhongming Yuan
- Department of Geriatrics, the Second Affiliated Hospital, Chongqing Medical University, Chongqing 400016, China
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Chan L, Albertsson-Wikland K, Camacho-Hübner C, Hochberg Z. Signal transduction in child health: closing the gap between clinical and basic research. Sci Signal 2010; 3:mr3. [PMID: 20940424 DOI: 10.1126/scisignal.3143mr3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Although some diseases are specific to children, many diseases of adults, including obesity and the metabolic syndrome, often originate in childhood. Thus, understanding the mechanisms of disease onset and progression in children is vital not only for child health, but for adult health as well. The NICHe (New Inroads to Child Health) Conference series focuses on future directions in child health, by bringing together clinical and basic scientists with the aim of sharing knowledge to facilitate the development of new therapeutic approaches. This year's conference, entitled "Child Health and Signal Transduction," focused on G protein-coupled receptor and receptor tyrosine kinase pathways involved in endocrine signaling, how disruption of these pathways can lead to disease, and how understanding these pathways may guide drug discovery.
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Affiliation(s)
- Li Chan
- Centre for Endocrinology, William Harvey Research Institute, St. Bartholomew's and The Royal London School of Medicine and Dentistry, London, UK.
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Glucose regulation of thrombospondin and its role in the modulation of smooth muscle cell proliferation. EXPERIMENTAL DIABETES RESEARCH 2010; 2010. [PMID: 20689700 PMCID: PMC2905704 DOI: 10.1155/2010/617052] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2010] [Revised: 04/05/2010] [Accepted: 04/16/2010] [Indexed: 11/17/2022]
Abstract
Smooth muscle cells (SMC) maintained in high glucose are more responsive to IGF-I than those in normal glucose. There is significantly more thrombospondin-1 (TSP-1) in extracellular matrix surrounding SMC grown in 25 mM glucose. In this study we investigated 1) the mechanism by which glucose regulates TSP-1 levels and 2) the mechanism by which TS-1 enhances IGF-I signaling. The addition of TSP-1 to primary SMC was sufficient to enhance IGF-I responsiveness in normal glucose. Reducing TSP-1 protein levels inhibited IGF-I signaling in SMC maintained in high glucose. We determined that TSP-1 protected IAP/CD47 from cleavage and thereby facilitated its association with SHP substrate-1 (SHPS-1). We have shown previously that the hyperglycemia induced protection of IAP from cleavage is an important component of the ability of hyperglycemia to enhance IGF-I signaling. Furthermore we determined that TSP-1 also enhanced phosphorylation of the beta3 subunit of the alphaVbeta3 integrin, another molecular event that we have shown are critical for SMC response to IGF-I in high glucose. Our studies also revealed that the difference in the amount of TSP-1 in the two different glucose conditions was due, at least in part, to a difference in the cellular uptake and degradation of TSP-1.
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