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Tierno IS, Agarwal M, Matisioudis N, Chandrakumar S, Ghosh K. Stiffness Measurement of Retinal Capillaries and Subendothelial Matrix using Atomic Force Microscopy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.28.582372. [PMID: 38464329 PMCID: PMC10925338 DOI: 10.1101/2024.02.28.582372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2024]
Abstract
Retinal capillary degeneration is a clinical hallmark of the early stages of diabetic retinopathy (DR). Our recent studies have revealed that diabetes-induced increase in retinal capillary stiffness plays a crucial and previously unrecognized causal role in inflammation-mediated degeneration of retinal capillaries. Retinal capillary stiffening results from overexpression of lysyl oxidase, an enzyme that crosslinks and stiffens the subendothelial matrix. Since tackling DR at the early stage is expected to prevent or slow down DR progression and associated vision loss, subendothelial matrix and capillary stiffness represent relevant and novel therapeutic targets for early DR management. Further, direct measurement of retinal capillary stiffness can serve as a crucial preclinical validation step for the development of new imaging techniques for non-invasive assessment of retinal capillary stiffness in animal and human subjects. With this view in mind, we here provide a detailed protocol for the isolation and stiffness measurement of mouse retinal capillaries and retinal subendothelial matrix using atomic force microscopy.
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Chandrakumar S, Santiago Tierno I, Agarwal M, Lessieur EM, Du Y, Tang J, Kiser J, Yang X, Rodriguez A, Kern TS, Ghosh K. Mechanical Regulation of Retinal Vascular Inflammation and Degeneration in Diabetes. Diabetes 2024; 73:280-291. [PMID: 37986627 PMCID: PMC10796303 DOI: 10.2337/db23-0584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 11/06/2023] [Indexed: 11/22/2023]
Abstract
Vascular inflammation is known to cause degeneration of retinal capillaries in early diabetic retinopathy (DR), a major microvascular complication of diabetes. Past studies investigating these diabetes-induced retinal vascular abnormalities have focused primarily on the role of molecular or biochemical cues. Here we show that retinal vascular inflammation and degeneration in diabetes are also mechanically regulated by the increase in retinal vascular stiffness caused by overexpression of the collagen-cross-linking enzyme lysyl oxidase (LOX). Treatment of diabetic mice with LOX inhibitor β-aminopropionitrile (BAPN) prevented the increase in retinal capillary stiffness, vascular intracellular adhesion molecule-1 overexpression, and leukostasis. Consistent with these anti-inflammatory effects, BAPN treatment of diabetic mice blocked the upregulation of proapoptotic caspase-3 in retinal vessels, which concomitantly reduced retinal capillary degeneration, pericyte ghost formation, and the diabetes-induced loss of contrast sensitivity in these mice. Finally, our in vitro studies indicate that retinal capillary stiffening is sufficient to increase the adhesiveness and neutrophil elastase-induced death of retinal endothelial cells. By uncovering a link between LOX-dependent capillary stiffening and the development of retinal vascular and functional defects in diabetes, these findings offer a new insight into DR pathogenesis that has important translational potential. ARTICLE HIGHLIGHTS
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Affiliation(s)
- Sathishkumar Chandrakumar
- Department of Ophthalmology, University of California, Los Angeles, Los Angeles, CA
- Doheny Eye Institute, Pasadena, CA
| | - Irene Santiago Tierno
- Department of Ophthalmology, University of California, Los Angeles, Los Angeles, CA
- Doheny Eye Institute, Pasadena, CA
- Molecular, Cellular, and Integrative Physiology Interdepartmental PhD Program, University of California, Los Angeles, Los Angeles, CA
| | - Mahesh Agarwal
- Department of Ophthalmology, University of California, Los Angeles, Los Angeles, CA
- Doheny Eye Institute, Pasadena, CA
| | - Emma M. Lessieur
- Department of Ophthalmology, Center for Translational Vision Research, University of California, Irvine, Irvine, CA
- Gavin Herbert Eye Institute, University of California, Irvine, CA
| | - Yunpeng Du
- Department of Ophthalmology, Center for Translational Vision Research, University of California, Irvine, Irvine, CA
- Gavin Herbert Eye Institute, University of California, Irvine, CA
| | - Jie Tang
- Department of Ophthalmology and Visual Science, Case Western Reserve University, Cleveland, OH
| | - Jianying Kiser
- Department of Ophthalmology, Center for Translational Vision Research, University of California, Irvine, Irvine, CA
- Gavin Herbert Eye Institute, University of California, Irvine, CA
| | - Xiao Yang
- Department of Bioengineering, University of California, Riverside, Riverside, CA
| | | | - Timothy S. Kern
- Department of Ophthalmology, Center for Translational Vision Research, University of California, Irvine, Irvine, CA
- Gavin Herbert Eye Institute, University of California, Irvine, CA
| | - Kaustabh Ghosh
- Department of Ophthalmology, University of California, Los Angeles, Los Angeles, CA
- Doheny Eye Institute, Pasadena, CA
- Molecular, Cellular, and Integrative Physiology Interdepartmental PhD Program, University of California, Los Angeles, Los Angeles, CA
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Hagemann T, Czechowski P, Ghosh A, Sun W, Dong H, Noé F, Wolfrum C, Blüher M, Hoffmann A. Laminin α4 Expression in Human Adipose Tissue Depots and Its Association with Obesity and Obesity Related Traits. Biomedicines 2023; 11:2806. [PMID: 37893179 PMCID: PMC10604865 DOI: 10.3390/biomedicines11102806] [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: 07/28/2023] [Revised: 10/02/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Laminin α4 (LAMA4) is one of the main structural adipocyte basement membrane (BM) components that is upregulated during adipogenesis and related to obesity in mice and humans. We conducted RNA-seq-based gene expression analysis of LAMA4 in abdominal subcutaneous (SC) and visceral (VIS) adipose tissue (AT) depots across three human sub-cohorts of the Leipzig Obesity BioBank (LOBB) to explore the relationship between LAMA4 expression and obesity (N = 1479) in the context of weight loss (N = 65) and metabolic health (N = 42). We found significant associations of LAMA4 with body fat mass (p < 0.001) in VIS AT; higher expression in VIS AT compared to SC AT; and significant relation to metabolic health parameters e.g., body fat in VIS AT, waist (p = 0.009) and interleukin 6 (p = 0.002) in male VIS AT, and hemoglobin A1c (p = 0.008) in male SC AT. AT LAMA4 expression was not significantly different between subjects with or without obesity, metabolically healthy versus unhealthy, and obesity before versus after short-term weight loss. Our results support significant associations between obesity related clinical parameters and elevated LAMA4 expression in humans. Our work offers one of the first references for understanding the meaning of LAMA4 expression specifically in relation to obesity based on large-scale RNA-seq data.
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Affiliation(s)
- Tobias Hagemann
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, 04103 Leipzig, Germany
| | - Paul Czechowski
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, 04103 Leipzig, Germany
| | - Adhideb Ghosh
- Institute of Food, Nutrition and Health, ETH Zurich, 8093 Schwerzenbach, Switzerland
| | - Wenfei Sun
- Institute of Food, Nutrition and Health, ETH Zurich, 8093 Schwerzenbach, Switzerland
| | - Hua Dong
- Institute of Food, Nutrition and Health, ETH Zurich, 8093 Schwerzenbach, Switzerland
| | - Falko Noé
- Institute of Food, Nutrition and Health, ETH Zurich, 8093 Schwerzenbach, Switzerland
| | - Christian Wolfrum
- Institute of Food, Nutrition and Health, ETH Zurich, 8093 Schwerzenbach, Switzerland
| | - Matthias Blüher
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, 04103 Leipzig, Germany
- Medical Department III—Endocrinology, Nephrology, Rheumatology, University of Leipzig Medical Center, 04103 Leipzig, Germany
| | - Anne Hoffmann
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, 04103 Leipzig, Germany
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Scuderi L, Fragiotta S, Di Pippo M, Abdolrahimzadeh S. The Role of Diabetic Choroidopathy in the Pathogenesis and Progression of Diabetic Retinopathy. Int J Mol Sci 2023; 24:10167. [PMID: 37373315 DOI: 10.3390/ijms241210167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/09/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
Diabetic choroidopathy was first described on histopathological specimens of diabetic eyes. This alteration was characterized by the accumulation of PAS-positive material within the intracapillary stroma. Inflammation and polymorphonuclear neutrophils (PMNs) activation are crucial elements in choriocapillaris impairment. The evidence of diabetic choroidopathy in vivo was confirmed with multimodal imaging, which provides key quantitative and qualitative features to characterize the choroidal involvement. The choroid can be virtually affected in each vascular layer, from Haller's layer to the choriocapillaris. However, the damage on the outer retina and photoreceptor cells is essentially driven by a choriocapillaris deficiency, which can be assessed through optical coherence tomography angiography (OCTA). The identification of characteristic features of diabetic choroidopathy can be significant for understanding the potential pathogenic and prognostic implications in diabetic retinopathy.
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Affiliation(s)
- Luca Scuderi
- Department of Sense Organs, Sapienza University of Rome, 00161 Rome, Italy
| | - Serena Fragiotta
- Ophthalmology Unit, Neurosciences, Mental Health, and Sensory Organs (NESMOS) Department, Sapienza University of Rome, Via di Grottarossa 1035/1039, 00189 Rome, Italy
- UOC Ophthalmology, Department of Surgical Areas, S.M. Goretti Hospital, 04100 Latina, Italy
| | - Mariachiara Di Pippo
- Ophthalmology Unit, Neurosciences, Mental Health, and Sensory Organs (NESMOS) Department, Sapienza University of Rome, Via di Grottarossa 1035/1039, 00189 Rome, Italy
| | - Solmaz Abdolrahimzadeh
- Ophthalmology Unit, Neurosciences, Mental Health, and Sensory Organs (NESMOS) Department, Sapienza University of Rome, Via di Grottarossa 1035/1039, 00189 Rome, Italy
- St. Andrea Hospital, Via di Grottarossa 1035/1039, 00189 Rome, Italy
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Askari S, Azizi F, Javadpour P, Karimi N, Ghasemi R. Endoplasmic reticulum stress as an underlying factor in leading causes of blindness and potential therapeutic effects of 4-phenylbutyric acid: from bench to bedside. EXPERT REVIEW OF OPHTHALMOLOGY 2022. [DOI: 10.1080/17469899.2022.2145945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Sahar Askari
- Neuroscience Research center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Department of Physiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Azizi
- Department of Neuroscience and Addiction Studies, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Pegah Javadpour
- Department of Physiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Nasser Karimi
- Eye and Skull Base Research Centers, The Five Senses Institute, Iran University of Medical Sciences, Tehran, Iran5Neurophysiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Rasoul Ghasemi
- Department of Physiology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Giblin MJ, Ontko CD, Penn JS. Effect of cytokine-induced alterations in extracellular matrix composition on diabetic retinopathy-relevant endothelial cell behaviors. Sci Rep 2022; 12:12955. [PMID: 35902594 PMCID: PMC9334268 DOI: 10.1038/s41598-022-12683-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 05/10/2022] [Indexed: 12/15/2022] Open
Abstract
Retinal vascular basement membrane (BM) thickening is an early structural abnormality of diabetic retinopathy (DR). Recent studies suggest that BM thickening contributes to the DR pathological cascade; however, much remains to be elucidated about the exact mechanisms by which BM thickening develops and subsequently drives other pathogenic events in DR. Therefore, we undertook a systematic analysis to understand how human retinal microvascular endothelial cells (hRMEC) and human retinal pericytes (hRP) change their expression of key extracellular matrix (ECM) constituents when treated with diabetes-relevant stimuli designed to model the three major insults of the diabetic environment: hyperglycemia, dyslipidemia, and inflammation. TNFα and IL-1β caused the most potent and consistent changes in ECM expression in both hRMEC and hRP. We also demonstrate that conditioned media from IL-1β-treated human Müller cells caused dose-dependent, significant increases in collagen IV and agrin expression in hRMEC. After narrowing our focus to inflammation-induced changes, we sought to understand how ECM deposited by hRMEC and hRP under inflammatory conditions affects the behavior of naïve hRMEC. Our data demonstrated that diabetes-relevant alterations in ECM composition alone cause both increased adhesion molecule expression by and increased peripheral blood mononuclear cell (PBMC) adhesion to naïve hRMEC. Taken together, these data demonstrate novel roles for inflammation and pericytes in driving BM pathology and suggest that inflammation-induced ECM alterations may advance other pathogenic behaviors in DR, including leukostasis.
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Affiliation(s)
- Meredith J. Giblin
- grid.152326.10000 0001 2264 7217Department of Cell and Developmental Biology, Vanderbilt University, Nashville, USA
| | - Cayla D. Ontko
- grid.152326.10000 0001 2264 7217Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, USA
| | - John S. Penn
- grid.152326.10000 0001 2264 7217Department of Cell and Developmental Biology, Vanderbilt University, Nashville, USA ,grid.152326.10000 0001 2264 7217Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, USA ,grid.412807.80000 0004 1936 9916Department of Ophthalmology and Visual Sciences, Vanderbilt University Medical Center, Nashville, USA
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Resnikoff HA, Miller CG, Schwarzbauer JE. Implications of fibrotic extracellular matrix in diabetic retinopathy. Exp Biol Med (Maywood) 2022; 247:1093-1102. [PMID: 35410521 PMCID: PMC9335512 DOI: 10.1177/15353702221087175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Fibrosis is an accumulation of extracellular matrix (ECM) proteins and fibers in a disordered fashion, which compromises cell and tissue functions. High glucose-induced fibrosis, a major pathophysiological change of diabetic retinopathy (DR), severely affects vision by compromising the retinal vasculature and ultimately disrupting retinal tissue organization. The retina is a highly vascularized, stratified tissue with multiple cell types organized into distinct layers. Chronically high blood glucose stimulates certain retinal cells to increase production and assembly of ECM proteins resulting in excess ECM deposition primarily in the capillary walls on the basal side of the endothelium. This subendothelial fibrosis of the capillaries is the earliest histological change in the diabetic retina and has been linked to the vascular dysfunction that underlies DR. Proteins that are not normally abundant in the capillary basement membrane (BM) matrix, such as the ECM protein fibronectin, are assembled in significant quantities, disrupting the architecture of the BM and altering its properties. Cell culture models have identified multiple mechanisms through which elevated glucose can stimulate fibronectin matrix assembly, including intracellular signaling pathways, alternative splicing, and non-enzymatic glycation of the ECM. The fibrotic subendothelial matrix alters cell adhesion and supports further accumulation of other ECM proteins leading to disruption of endothelial cell-cell junctions. We review evidence supporting the notion that these molecular changes in the ECM contribute to the pathogenesis of DR, including vascular leakage, loss of endothelial cells and pericytes, changes in blood flow, and neovascularization. We propose that the accumulation of ECM, especially fibronectin matrix, first around the vasculature and later in extravascular locations, plays a critical role in DR and vision loss. Strategies for DR prevention and treatment should consider the ECM a potential therapeutic target.
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Affiliation(s)
- Henry A Resnikoff
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA
| | - Charles G Miller
- Department of Ophthalmology, Scheie Eye Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Jean E Schwarzbauer
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544-1014, USA,Jean E Schwarzbauer.
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R-spondin 3 Inhibits High Glucose-Induced Endothelial Activation Through Leucine-Rich G Protein-Coupled Receptor 4/Wnt/β-catenin Pathway. J Cardiovasc Pharmacol 2022; 80:70-81. [PMID: 35767713 DOI: 10.1097/fjc.0000000000001295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 04/22/2022] [Indexed: 11/26/2022]
Abstract
ABSTRACT High glucose-induced endothelial activation plays critical roles in the development of diabetic vascular complications. R-spondin 3 could inhibit inflammatory damage, and diabetic vascular inflammation is secondary to endothelial activation. In this article, we identify R-spondin 3 as a novel regulator of high glucose-induced endothelial activation. We found that the serum levels of R-spondin 3 were significantly reduced in type 2 diabetic patients and db/db mice. We observed that the increased expressions of vascular cell adhesion molecule-1, intercellular cell adhesion molecule-1, and monocyte chemoattractant protein-1 (endothelial activation makers) in high glucose-stimulated human umbilical vein endothelial cell lines (HUVECs) could be inhibited by overexpressing R-spondin 3 or human R-spondin 3 recombinant protein. Subsequently, high glucose-induced adhesion and migration of human myeloid leukemia mononuclear cells (THP-1 cells) to HUVECs were markedly suppressed by the overexpression of R-spondin 3 in HUVECs. Moreover, the inhibitory effect of R-spondin 3 on the expressions of vascular cell adhesion molecule-1, intercellular cell adhesion molecule-1, and monocyte chemoattractant protein-1 in high glucose-treated HUVECs could be blocked by knockdown of leucine-rich G protein-coupled receptor 4 (R-spondin 3 receptor) or the specific inhibitor of Wnt/β-catenin pathway. Taken together, R-spondin 3 could suppress high glucose-induced endothelial activation through leucine-rich G protein-coupled receptor 4/Wnt/β-catenin pathway.
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Pahapale GJ, Tao J, Nikolic M, Gao S, Scarcelli G, Sun SX, Romer LH, Gracias DH. Directing Multicellular Organization by Varying the Aspect Ratio of Soft Hydrogel Microwells. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2104649. [PMID: 35434926 PMCID: PMC9189654 DOI: 10.1002/advs.202104649] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 03/08/2022] [Indexed: 06/03/2023]
Abstract
Multicellular organization with precise spatial definition is essential to various biological processes, including morphogenesis, development, and healing in vascular and other tissues. Gradients and patterns of chemoattractants are well-described guides of multicellular organization, but the influences of 3D geometry of soft hydrogels are less well defined. Here, the discovery of a new mode of endothelial cell self-organization guided by combinatorial effects of stiffness and geometry, independent of protein or chemical patterning, is described. Endothelial cells in 2 kPa microwells are found to be ≈30 times more likely to migrate to the edge to organize in ring-like patterns than in stiff 35 kPa microwells. This organization is independent of curvature and significantly more pronounced in 2 kPa microwells with aspect ratio (perimeter/depth) < 25. Physical factors of cells and substrates that drive this behavior are systematically investigated and a mathematical model that explains the organization by balancing the dynamic interaction between tangential cytoskeletal tension, cell-cell, and cell-substrate adhesion is presented. These findings demonstrate the importance of combinatorial effects of geometry and stiffness in complex cellular organization that can be leveraged to facilitate the engineering of bionics and integrated model organoid systems with customized nutrient vascular networks.
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Affiliation(s)
- Gayatri J. Pahapale
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
| | - Jiaxiang Tao
- Department of Mechanical EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
| | - Milos Nikolic
- Maryland Biophysics ProgramInstitute for Physical Science and TechnologyUniversity of MarylandCollege ParkMD20742USA
| | - Sammy Gao
- Department of Chemical and Biomolecular EngineeringJohns Hopkins UniversityBaltimoreMD21218USA
| | - Giuliano Scarcelli
- Maryland Biophysics ProgramInstitute for Physical Science and Technology and Fischell Department of BioengineeringUniversity of MarylandCollege ParkMD20742USA
| | - Sean X. Sun
- Department of Mechanical EngineeringCell Biologyand Institute of NanoBioTechnology (INBT)Johns Hopkins UniversityBaltimoreMD21218USA
| | - Lewis H. Romer
- Department of Cell BiologyAnesthesiology and Critical Care MedicineBiomedical EngineeringPediatricsand Center for Cell DynamicsJohns Hopkins School of MedicineBaltimoreMD21205USA
| | - David H. Gracias
- Department of Chemical and Biomolecular EngineeringMaterials Science and EngineeringChemistry and Laboratory for Computational Sensing and Robotics (LCSR)Johns Hopkins UniversityBaltimoreMD21218USA
- Department of Oncology and Sidney Kimmel Comprehensive Cancer CenterJohns Hopkins School of MedicineBaltimoreMD21205USA
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10
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Cabrera AP, Stoddard J, Santiago Tierno I, Matisioudis N, Agarwal M, Renner L, Palegar N, Neuringer M, McGill T, Ghosh K. Increased cell stiffness contributes to complement-mediated injury of choroidal endothelial cells in a monkey model of early age-related macular degeneration. J Pathol 2022; 257:314-326. [PMID: 35239183 DOI: 10.1002/path.5892] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/03/2022] [Accepted: 03/01/2022] [Indexed: 11/06/2022]
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness in the aging population. Yet, no therapies exist for approximately 85% of all AMD patients who have the dry form that is marked by degeneration of the retinal pigmented epithelium (RPE) and underlying choroidal vasculature. As the choroidal vessels are crucial for RPE development and maintenance, understanding how they degenerate may lead to effective therapies for dry AMD. One likely causative factor for choroidal vascular loss is the cytolytic membrane attack complex (MAC) of the complement pathway that is abundant on choroidal vessels of humans with early dry AMD. To examine this possibility, we studied the effect of complement activation on choroidal endothelial cells (ECs) isolated from a rhesus monkey model of early AMD that, we report, exhibits MAC deposition and choriocapillaris endothelial loss similar to that seen in human early AMD. Treatment of choroidal ECs from AMD eyes with complement-competent normal human serum caused extensive actin cytoskeletal injury that was significantly less pronounced in choroidal ECs from young normal monkey eyes. We further show that ECs from AMD eyes are significantly stiffer than their younger counterparts and exhibit peripheral actin organization that is distinct from the longitudinal stress fibers in young ECs. Finally, these differences in complement susceptibility and mechanostructural properties were found to be regulated by the differential activity of the small GTPases Rac and Rho, because Rac inhibition in AMD cells led to simultaneous reduction in stiffness and complement susceptibility while Rho inhibition in young cells exacerbated complement injury. Thus, by identifying cell stiffness and cytoskeletal regulators Rac and Rho as important determinants of complement susceptibility, the current findings offer a new mechanistic insight into choroidal vascular loss in early AMD that warrants further investigation for assessment of translational potential. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Andrea P Cabrera
- Department of Bioengineering, University of California, Riverside, CA, USA
| | - Jonathan Stoddard
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Sciences University, Beaverton, OR, USA
| | - Irene Santiago Tierno
- Department of Ophthalmology and Integrated Physiology Interdepartmental PhD Program, University of California, Los Angeles, CA, USA.,Molecular, Cellular, and Integrated Physiology Interdepartmental PhD Program, University of California, Los Angeles, CA, USA.,Doheny Eye Institute, Pasadena, CA, USA
| | | | - Mahesh Agarwal
- Department of Ophthalmology and Integrated Physiology Interdepartmental PhD Program, University of California, Los Angeles, CA, USA.,Doheny Eye Institute, Pasadena, CA, USA
| | - Lauren Renner
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Sciences University, Beaverton, OR, USA
| | - Neha Palegar
- Department of Bioengineering, University of California, Riverside, CA, USA
| | - Martha Neuringer
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Sciences University, Beaverton, OR, USA.,Casey Eye Institute, Oregon Health & Sciences University, Portland, OR, USA
| | - Trevor McGill
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Sciences University, Beaverton, OR, USA.,Casey Eye Institute, Oregon Health & Sciences University, Portland, OR, USA
| | - Kaustabh Ghosh
- Department of Bioengineering, University of California, Riverside, CA, USA.,Department of Ophthalmology and Integrated Physiology Interdepartmental PhD Program, University of California, Los Angeles, CA, USA.,Molecular, Cellular, and Integrated Physiology Interdepartmental PhD Program, University of California, Los Angeles, CA, USA.,Doheny Eye Institute, Pasadena, CA, USA
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11
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Lau S, Gossen M, Lendlein A. Designing Cardiovascular Implants Taking in View the Endothelial Basement Membrane. Int J Mol Sci 2021; 22:ijms222313120. [PMID: 34884923 PMCID: PMC8658568 DOI: 10.3390/ijms222313120] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/25/2021] [Accepted: 11/29/2021] [Indexed: 12/28/2022] Open
Abstract
Insufficient endothelialization of cardiovascular grafts is a major hurdle in vascular surgery and regenerative medicine, bearing a risk for early graft thrombosis. Neither of the numerous strategies pursued to solve these problems were conclusive. Endothelialization is regulated by the endothelial basement membrane (EBM), a highly specialized part of the vascular extracellular matrix. Thus, a detailed understanding of the structure–function interrelations of the EBM components is fundamental for designing biomimetic materials aiming to mimic EBM functions. In this review, a detailed description of the structure and functions of the EBM are provided, including the luminal and abluminal interactions with adjacent cell types, such as vascular smooth muscle cells. Moreover, in vivo as well as in vitro strategies to build or renew EBM are summarized and critically discussed. The spectrum of methods includes vessel decellularization and implant biofunctionalization strategies as well as tissue engineering-based approaches and bioprinting. Finally, the limitations of these methods are highlighted, and future directions are suggested to help improve future design strategies for EBM-inspired materials in the cardiovascular field.
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Affiliation(s)
- Skadi Lau
- Institute of Active Polymers and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Hereon, Kantstraße 55, 14513 Teltow, Germany; (S.L.); (M.G.)
| | - Manfred Gossen
- Institute of Active Polymers and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Hereon, Kantstraße 55, 14513 Teltow, Germany; (S.L.); (M.G.)
| | - Andreas Lendlein
- Institute of Active Polymers and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Hereon, Kantstraße 55, 14513 Teltow, Germany; (S.L.); (M.G.)
- Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Straße 25, 14476 Potsdam, Germany
- Correspondence:
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12
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Iturriaga-Goyon E, Buentello-Volante B, Magaña-Guerrero FS, Garfias Y. Future Perspectives of Therapeutic, Diagnostic and Prognostic Aptamers in Eye Pathological Angiogenesis. Cells 2021; 10:cells10061455. [PMID: 34200613 PMCID: PMC8227682 DOI: 10.3390/cells10061455] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 06/04/2021] [Accepted: 06/05/2021] [Indexed: 12/23/2022] Open
Abstract
Aptamers are single-stranded DNA or RNA oligonucleotides that are currently used in clinical trials due to their selectivity and specificity to bind small molecules such as proteins, peptides, viral particles, vitamins, metal ions and even whole cells. Aptamers are highly specific to their targets, they are smaller than antibodies and fragment antibodies, they can be easily conjugated to multiple surfaces and ions and controllable post-production modifications can be performed. Aptamers have been therapeutically used for age-related macular degeneration, cancer, thrombosis and inflammatory diseases. The aim of this review is to highlight the therapeutic, diagnostic and prognostic possibilities associated with aptamers, focusing on eye pathological angiogenesis.
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Affiliation(s)
- Emilio Iturriaga-Goyon
- MD/PhD (PECEM) Program, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico;
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
- Department of Biochemistry, Facultad de Medicina, Universidad Nacional Autónoma de México, Av. Universidad 3000, Mexico City 04510, Mexico
| | - Beatriz Buentello-Volante
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
| | - Fátima Sofía Magaña-Guerrero
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
| | - Yonathan Garfias
- Cell and Tissue Biology, Research Unit, Institute of Ophthalmology, Conde de Valenciana, Chimalpopoca 14, Mexico City 06800, Mexico; (B.B.-V.); (F.S.M.-G.)
- Department of Biochemistry, Facultad de Medicina, Universidad Nacional Autónoma de México, Av. Universidad 3000, Mexico City 04510, Mexico
- Correspondence:
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13
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Behmer Hansen RA, Wang X, Kaw G, Pierre V, Senyo SE. Accounting for Material Changes in Decellularized Tissue with Underutilized Methodologies. BIOMED RESEARCH INTERNATIONAL 2021; 2021:6696295. [PMID: 34159202 PMCID: PMC8187050 DOI: 10.1155/2021/6696295] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 05/05/2021] [Accepted: 05/21/2021] [Indexed: 11/17/2022]
Abstract
Tissue decellularization has rapidly developed to be a practical approach in tissue engineering research; biological tissue is cleared of cells resulting in a protein-rich husk as a natural scaffold for growing transplanted cells as a donor organ therapy. Minimally processed, acellular extracellular matrix reproduces natural interactions with cells in vitro and for tissue engineering applications in animal models. There are many decellularization techniques that achieve preservation of molecular profile (proteins and sugars), microstructure features such as organization of ECM layers (interstitial matrix and basement membrane) and organ level macrofeatures (vasculature and tissue compartments). While structural and molecular cues receive attention, mechanical and material properties of decellularized tissues are not often discussed. The effects of decellularization on an organ depend on the tissue properties, clearing mechanism, chemical interactions, solubility, temperature, and treatment duration. Physical characterization by a few labs including work from the authors provides evidence that decellularization protocols should be tailored to specific research questions. Physical characterization beyond histology and immunohistochemistry of the decellularized matrix (dECM) extends evaluation of retained functional features of the original tissue. We direct our attention to current technologies that can be employed for structure function analysis of dECM using underutilized tools such as atomic force microscopy (AFM), cryogenic electron microscopy (cryo-EM), dynamic mechanical analysis (DMA), Fourier-transform infrared spectroscopy (FTIR), mass spectrometry, and rheometry. Structural imaging and mechanical functional testing combined with high-throughput molecular analyses opens a new approach for a deeper appreciation of how cellular behavior is influenced by the isolated microenvironment (specifically dECM). Additionally, the impact of these features with different decellularization techniques and generation of synthetic material scaffolds with desired attributes are informed. Ultimately, this mechanical profiling provides a new dimension to our understanding of decellularized matrix and its role in new applications.
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Affiliation(s)
- Ryan A. Behmer Hansen
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Xinming Wang
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Gitanjali Kaw
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Valinteshley Pierre
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Samuel E. Senyo
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
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14
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Cappelli HC, Guarino BD, Kanugula AK, Adapala RK, Perera V, Smith MA, Paruchuri S, Thodeti CK. Transient receptor potential vanilloid 4 channel deletion regulates pathological but not developmental retinal angiogenesis. J Cell Physiol 2021; 236:3770-3779. [PMID: 33078410 PMCID: PMC7920906 DOI: 10.1002/jcp.30116] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 10/07/2020] [Accepted: 10/09/2020] [Indexed: 01/08/2023]
Abstract
Transient receptor potential vanilloid 4 (TRPV4) channels are mechanosensitive ion channels that regulate systemic endothelial cell (EC) functions such as vasodilation, permeability, and angiogenesis. TRPV4 is expressed in retinal ganglion cells, Müller glia, pigment epithelium, microvascular ECs, and modulates cell volume regulation, calcium homeostasis, and survival. TRPV4-mediated physiological or pathological retinal angiogenesis remains poorly understood. Here, we demonstrate that TRPV4 is expressed, functional, and mechanosensitive in retinal ECs. The genetic deletion of TRPV4 did not affect postnatal developmental angiogenesis but increased pathological neovascularization in response to oxygen-induced retinopathy (OIR). Retinal vessels from TRPV4 knockout mice subjected to OIR exhibited neovascular tufts that projected into the vitreous humor and displayed reduced pericyte coverage compared with wild-type mice. These results suggest that TRPV4 is a regulator of retinal angiogenesis, its deletion augments pathological retinal angiogenesis, and that TRPV4 could be a novel target for the development of therapies against neovascular ocular diseases.
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Affiliation(s)
- Holly C. Cappelli
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
- School of Biomedical Sciences, Kent State University, Kent, OH 44240
| | - Brianna D. Guarino
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
| | - Anantha K. Kanugula
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
| | - Ravi K. Adapala
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
- School of Biomedical Sciences, Kent State University, Kent, OH 44240
| | - Vidushani Perera
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
| | - Matthew A. Smith
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
- Rebbeca D. Considine Research Institute, Akron Children’s Hospital, Akron, OH 44302
| | | | - Charles K. Thodeti
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH 44272
- School of Biomedical Sciences, Kent State University, Kent, OH 44240
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15
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Roy S, Kim D. Retinal capillary basement membrane thickening: Role in the pathogenesis of diabetic retinopathy. Prog Retin Eye Res 2020; 82:100903. [PMID: 32950677 DOI: 10.1016/j.preteyeres.2020.100903] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 09/08/2020] [Accepted: 09/15/2020] [Indexed: 02/07/2023]
Abstract
Vascular basement membrane (BM) thickening has been hailed over half a century as the most prominent histological lesion in diabetic microangiopathy, and represents an early ultrastructural change in diabetic retinopathy (DR). Although vascular complications of DR have been clinically well established, specific cellular and molecular mechanisms underlying dysfunction of small vessels are not well understood. In DR, small vessels develop insidiously as BM thickening occurs. Studies examining high resolution imaging data have established BM thickening as one of the foremost structural abnormalities of retinal capillaries. This fundamental structural change develops, at least in part, from excess accumulation of BM components. Although BM thickening is closely associated with the development of DR, its contributory role in the pathogenesis of DR is coming to light recently. DR develops over several years before clinical manifestations appear, and it is during this clinically silent period that hyperglycemia induces excess synthesis of BM components, contributes to vascular BM thickening, and promotes structural and functional lesions including cell death and vascular leakage in the diabetic retina. Studies using animal models show promising results in preventing BM thickening with subsequent beneficial effects. Several gene regulatory approaches are being developed to prevent excess synthesis of vascular BM components in an effort to reduce BM thickening. This review highlights current understanding of capillary BM thickening development, role of BM thickening in retinal vascular lesions, and strategies for preventing vascular BM thickening as a potential therapeutic strategy in alleviating characteristic lesions associated with DR.
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Affiliation(s)
- Sayon Roy
- Boston University School of Medicine, Boston, MA, USA.
| | - Dongjoon Kim
- Boston University School of Medicine, Boston, MA, USA
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16
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Gamidov AA, Baryshev KV, Perevozchikov KA, Surnina ZV. [Atomic force microscopy in the study of retinal structure]. Vestn Oftalmol 2020; 136:251-257. [PMID: 32880147 DOI: 10.17116/oftalma2020136042251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The review addresses the current state of atomic force microscopy (AFM) usage in ophthalmology. Briefly presented here are the history of the development of AFM, principles and modes of operation, its advantages, disadvantages, as well as a comparison with other types of microscopy. The review describes the capabilities of AFM in visualization of various structures of the eye. A significant part of the review is devoted to the study of the retina, which arouses great interest among researchers. In particular, the possibilities of AFM for visualization at the submicron level of various structures in the retina, such as the internal limiting membrane, membrane cells, Müller cells, retinal pigment epithelium in their normal state and in the presence of a pathology (age-related macular degeneration, diabetes mellitus) were reviewed. In addition, several study papers were analyzed, providing a base for the judgement of the mechanical properties of said structures. An AFM study of the visual pigment rhodopsin helped identify its dimeric structure. The stability of the rhodopsin molecule was proved to be determined by the degree of strength of its individual segments connected to each other. The AFM method is a highly accurate method that helps solve many fundamental and practical problems, particularly in ophthalmology.
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Affiliation(s)
- A A Gamidov
- Research Institute of Eye Diseases, Moscow, Russia
| | - K V Baryshev
- Research Institute of Eye Diseases, Moscow, Russia
| | | | - Z V Surnina
- Research Institute of Eye Diseases, Moscow, Russia
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17
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Wei S, Gao L, Wu C, Qin F, Yuan J. Role of the lysyl oxidase family in organ development (Review). Exp Ther Med 2020; 20:163-172. [PMID: 32536990 PMCID: PMC7282176 DOI: 10.3892/etm.2020.8731] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 03/02/2020] [Indexed: 02/05/2023] Open
Abstract
Lysyl oxidase proteins (LOXs) are amine oxidases, which are mainly located in smooth muscle cells and fibroblasts and serve an important role in the formation of the extracellular matrix (ECM) in a copper-dependent manner. Owing to the ability of LOX proteins to modulate crosslinking between collagens and to promote the deposition of other fibers, they serve crucially in organogenesis and the subsequent organ development, as well as disease initiation and progression. In addition, ECM formation significantly influences organ morphological formation in both cancer- and non-tumor-related diseases, in addition to cellular epigenetic transformation and migration, under the influence of LOXs. A number of different signaling pathways regulate the LOXs expression and their enzymatic activation. The tissue remodeling and transformation process shares some resemblance between oncogenesis and embryogenesis. Additionally the roles that LOXs serve appeared to be stressed during oncogenesis and tumor metastasis. It has also been indicated LOXs have a noteworthy role in non-tumor diseases. Nonetheless, the role of LOXs in systemic or local organ development and disease control remains unknown. In the present study, the essential roles that LOXs play in embryogenesis were unveiled partially, whereas the role of LOXs in organ or systematic development requires further investigations. The present review aimed to discuss the roles of members of the LOX family in the context of the remodeling of organogenesis and organ development. In addition, the consequences of the malfunction of these proteins related to the development of abnormalities and resulting diseases is discussed.
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Affiliation(s)
- Shanzun Wei
- Andrology Laboratory, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Liang Gao
- Andrology Laboratory, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Changjing Wu
- Andrology Laboratory, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Feng Qin
- Andrology Laboratory, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Jiuhong Yuan
- Andrology Laboratory, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China.,Department of Urology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, P.R. China
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18
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Pradhan S, Banda OA, Farino CJ, Sperduto JL, Keller KA, Taitano R, Slater JH. Biofabrication Strategies and Engineered In Vitro Systems for Vascular Mechanobiology. Adv Healthc Mater 2020; 9:e1901255. [PMID: 32100473 PMCID: PMC8579513 DOI: 10.1002/adhm.201901255] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 01/24/2020] [Indexed: 12/17/2022]
Abstract
The vascular system is integral for maintaining organ-specific functions and homeostasis. Dysregulation in vascular architecture and function can lead to various chronic or acute disorders. Investigation of the role of the vascular system in health and disease has been accelerated through the development of tissue-engineered constructs and microphysiological on-chip platforms. These in vitro systems permit studies of biochemical regulation of vascular networks and parenchymal tissue and provide mechanistic insights into the biophysical and hemodynamic forces acting in organ-specific niches. Detailed understanding of these forces and the mechanotransductory pathways involved is necessary to develop preventative and therapeutic strategies targeting the vascular system. This review describes vascular structure and function, the role of hemodynamic forces in maintaining vascular homeostasis, and measurement approaches for cell and tissue level mechanical properties influencing vascular phenomena. State-of-the-art techniques for fabricating in vitro microvascular systems, with varying degrees of biological and engineering complexity, are summarized. Finally, the role of vascular mechanobiology in organ-specific niches and pathophysiological states, and efforts to recapitulate these events using in vitro microphysiological systems, are explored. It is hoped that this review will help readers appreciate the important, but understudied, role of vascular-parenchymal mechanotransduction in health and disease toward developing mechanotherapeutics for treatment strategies.
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Affiliation(s)
- Shantanu Pradhan
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras, Chennai 600036, India
| | - Omar A. Banda
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - Cindy J. Farino
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - John L. Sperduto
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - Keely A. Keller
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - Ryan Taitano
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
| | - John H. Slater
- Department of Biomedical Engineering, University of Delaware, 150 Academy Street, 161 Colburn Lab, Newark, DE, 19716, USA
- Department of Materials Science and Engineering, University of Delaware, 201 DuPont Hall, Newark, DE 19716, USA
- Delaware Biotechnology Institute, 15 Innovation Way, Newark, DE 19711, USA
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19
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Abstract
Physical stimuli are essential for the function of eukaryotic cells, and changes in physical signals are important elements in normal tissue development as well as in disease initiation and progression. The complexity of physical stimuli and the cellular signals they initiate are as complex as those triggered by chemical signals. One of the most important, and the focus of this review, is the effect of substrate mechanical properties on cell structure and function. The past decade has produced a nearly exponentially increasing number of mechanobiological studies to define how substrate stiffness alters cell biology using both purified systems and intact tissues. Here we attempt to identify common features of mechanosensing in different systems while also highlighting the numerous informative exceptions to what in early studies appeared to be simple rules by which cells respond to mechanical stresses.
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Affiliation(s)
- Paul A Janmey
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of California-Berkeley, Berkeley, California; and Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Daniel A Fletcher
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of California-Berkeley, Berkeley, California; and Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
| | - Cynthia A Reinhart-King
- Department of Physiology, Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Bioengineering, University of California-Berkeley, Berkeley, California; and Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee
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20
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Kim D, Lee D, Trackman PC, Roy S. Effects of High Glucose-Induced Lysyl Oxidase Propeptide on Retinal Endothelial Cell Survival: Implications for Diabetic Retinopathy. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:1945-1952. [PMID: 31537300 PMCID: PMC6880772 DOI: 10.1016/j.ajpath.2019.06.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 06/17/2019] [Accepted: 06/20/2019] [Indexed: 01/19/2023]
Abstract
Diabetic retinopathy (DR) is characterized by apoptotic cell loss in the retinal vasculature. Lysyl oxidase propeptide (LOX-PP), released during LOX processing, has been implicated in promoting apoptosis in various diseased tissues. However, its role in the development and progression of DR is unknown. We investigated whether high glucose (HG) or diabetes alters LOX-PP expression and thereby influences AKT pathway and affects retinal endothelial cell survival. Rat retinal endothelial cells were grown in normal medium, normal medium and exposed to recombinant LOX-PP (rLOX-PP) or HG medium and examined for LOX-PP expression, AKT and caspase-3 activation. Similarly, rats intravitreally injected with rLOX-PP were examined for changes in retinal LOX-PP levels, AKT phosphorylation, and the number of acellular capillaries and pericyte loss compared with those of control diabetic and nondiabetic rats. Results indicate that HG up-regulates LOX-PP expression and reduces AKT activation. In addition, cells exposed to rLOX-PP alone exhibited increased apoptosis concomitant with decreased AKT phosphorylation. In retinas of diabetic rats, increased LOX-PP level, decreased AKT phosphorylation, and increased number of acellular capillaries and pericyte loss compared with those of nondiabetic rats were observed. Of interest, similar changes were noted in the retinas of rats injected with rLOX-PP. Findings from this study suggest that hyperglycemia-induced LOX-PP overexpression may contribute to retinal vascular cell loss associated with DR.
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Affiliation(s)
- Dongjoon Kim
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Dayeun Lee
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - Philip C Trackman
- Department of Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, Massachusetts
| | - Sayon Roy
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts; Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts.
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21
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Upregulation of Lysyl Oxidase Expression in Vitreous of Diabetic Subjects: Implications for Diabetic Retinopathy. Cells 2019; 8:cells8101122. [PMID: 31546618 PMCID: PMC6829411 DOI: 10.3390/cells8101122] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 09/19/2019] [Accepted: 09/20/2019] [Indexed: 01/03/2023] Open
Abstract
Animal studies have shown diabetes-induced lysyl oxidase (LOX) upregulation promotes blood-retinal-barrier breakdown and retinal vascular cell loss associated with diabetic retinopathy (DR). However, it is unclear whether changes in LOX expression contribute to the development and progression of DR. To determine if vitreous LOX levels are altered in patients with DR, 31 vitreous specimens from subjects with advanced proliferative DR (PDR), and 27 from non-diabetics were examined. The two groups were age- and gender-matched (57 ± 12 yrs vs. 53 ± 18 yrs; 19 males and 12 females vs. 17 males and 10 females). Vitreous samples obtained during vitrectomy were assessed for LOX levels using ELISA. LOX was detected in a larger number of PDR subjects (58%) than in non-diabetic subjects (15%). Additionally, ELISA measurements showed a significant increase in LOX levels in the diabetic subjects with PDR, compared to those of non-diabetic subjects (68.3 ± 112 ng/mL vs. 2.1 ± 8.2 ng/mL; p < 0.01). No gender difference in vitreous LOX levels was observed in either the diabetic or non-diabetic groups. Findings support previous reports of increased LOX levels in retinas of diabetic animals and in retinal vascular cells in high glucose condition, raising the prospect of targeting LOX overexpression as a potential target for PDR treatment.
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22
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Song B, Kim D, Nguyen NH, Roy S. Inhibition of Diabetes-Induced Lysyl Oxidase Overexpression Prevents Retinal Vascular Lesions Associated With Diabetic Retinopathy. Invest Ophthalmol Vis Sci 2019; 59:5965-5972. [PMID: 30550614 PMCID: PMC6295938 DOI: 10.1167/iovs.18-25543] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Purpose The purpose of this study was to investigate the effect of reducing diabetes-induced lysyl oxidase (LOX) overexpression on vascular cell apoptosis and blood-retinal barrier (BRB) characteristics in diabetic rats. Methods Nondiabetic rats, diabetic rats, and diabetic rats intravitreally (IV) injected with LOX siRNA or scrambled (scram) siRNA were used in the study. One month after the onset of diabetes, intravitreal injections were initiated at monthly intervals for up to three times. At the end of study, retinal capillary networks were isolated, stained with periodic acid-Schiff (PAS) and hematoxylin, and assessed for acellular capillaries (AC) and pericyte loss (PL). To assess vascular leakage, extravasation of FITC-dextran was evaluated in retinal capillaries after tail vein injection of FITC-dextran. Western blot analysis was performed to determine retinal LOX level and confirm LOX downregulation via LOX siRNA intravitreal injection. Results LOX expression was significantly upregulated in retinas of diabetic rats compared with that of nondiabetic rats. Diabetic rats injected with LOX siRNA showed a significant decrease in retinal LOX expression compared with those of diabetic rats or scram siRNA-injected rats. In diabetic retinas, AC and PL were significantly increased compared with those of nondiabetic retinas. Importantly, diabetic rats treated with LOX siRNA exhibited a significant decrease in AC and PL counts compared with those of untreated diabetic rats. Furthermore, diabetic rats treated with LOX siRNA showed significant decrease in retinal vascular permeability compared with that of untreated diabetic rats. Conclusions Findings suggest LOX siRNA intravitreal injection may be effective against diabetes-induced LOX overexpression in preventing apoptosis and vascular leakage associated with diabetic retinopathy.
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Affiliation(s)
- Brian Song
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States.,Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Dongjoon Kim
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States.,Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Ngan-Ha Nguyen
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States.,Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Sayon Roy
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States.,Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
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23
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Liu M, Xu J, Zandi R, Mohideen U. Measurement of entropic force from polymers attached to a pyramidal tip. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:075102. [PMID: 30524055 DOI: 10.1088/1361-648x/aaf51a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The measurement of the boundary shape dependence of the entropic force from long polymers was attempted. The pyramidal cone-plate geometry was chosen. The polymer molecules were covalently bound to a well-defined Au patch at the apex of a pyramidal cantilever tip of the atomic force microscope (AFM). A smooth hydrophobic plate was used as the second boundary to confine the polymer molecules. The use of the hydrophobic plate allows neglect of polymer adhesion forces. The measurements were made in salt water solution to decrease the effect of electrostatic forces from any uncompensated charges on the boundary. As the functionalized AFM tip approaches the flat hydrophobic surface, the induced entropic forces were measured as a function of the separation distance. The measured force-distance curves are compared with a model of polymer-mediated entropic force between scale-free objects and the Alexander-de Gennes (AdG) theory for a polymer brush.
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Affiliation(s)
- Mingyue Liu
- Department of Physics and Astronomy, University of California, Riverside, CA 92521, United States of America
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24
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Shanmuganathan S, Angayarkanni N. Chebulagic acid and Chebulinic acid inhibit TGF-β1 induced fibrotic changes in the chorio-retinal endothelial cells by inhibiting ERK phosphorylation. Microvasc Res 2018; 121:14-23. [PMID: 30189210 DOI: 10.1016/j.mvr.2018.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 07/18/2018] [Accepted: 09/03/2018] [Indexed: 01/07/2023]
Abstract
PURPOSE Diabetic retinopathy (DR) is characterized by pro-inflammatory, pro-angiogenic and pro-fibrotic environment during the various stages of the disease progression. Basement membrane changes in the retina and formation of fibrovascular membrane are characteristically seen in DR. In the present study the effect of Alcoholic (AlE) extracts of Triphala an ayurvedic herbal formulation and its chief compounds, Chebulagic (CA), Chebulinic (CI) and Gallic acid (GA) were evaluated for TGFβ1-induced anti-fibrotic activity in choroid-retinal endothelial cells (RF/6A). METHOD RF/6A cells were treated with TGFβ1 alone or co-treated with AlE, CA, CI or GA. The mRNA and protein expression of fibrotic markers (αSMA, CTGF) were assessed by qPCR and western blot/ELISA. Functional changes were assessed using proliferation assay and migration assay. To deduce the mechanism of action, downstream signaling was assessed by western blot analysis along with in silico docking studies. RESULT AlE (50 μg/ml) CA and CI at 10 μM reduced the expression of pro-fibrotic genes (αSMA and CTGF) induced by TGFβ1, by inhibiting ERK phosphorylation. GA did not inhibit TGFβ1 mediated changes in RF/6A cells. In silico experiments shows that CA and CI has favourable binding energy to bind with TGFβ receptor and inhibit the downstream signaling, while GA did not. CONCLUSION Hence this study identifies Triphala and its chief compounds CA and CI as potential adjuvants in the management of DR.
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Affiliation(s)
- Sivasankar Shanmuganathan
- R.S Mehta Jain Department of Biochemistry and Cell biology, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India; School of Chemical and Biotechnology, SASTRA University, Thanjavur 613 401, India
| | - Narayanasamy Angayarkanni
- R.S Mehta Jain Department of Biochemistry and Cell biology, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Vision Research Foundation, Sankara Nethralaya, Chennai 600 006, India.
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25
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Qu J, Zhu L, Zhou Z, Chen P, Liu S, Locy ML, Thannickal VJ, Zhou Y. Reversing Mechanoinductive DSP Expression by CRISPR/dCas9-mediated Epigenome Editing. Am J Respir Crit Care Med 2018; 198:599-609. [PMID: 29924937 PMCID: PMC6118013 DOI: 10.1164/rccm.201711-2242oc] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 06/20/2018] [Indexed: 12/29/2022] Open
Abstract
RATIONALE DSP (desmoplakin), the most abundant component of desmosomes, which maintain the mechanical integrity of epithelium, is a genome-wide association study-identified genetic risk locus in human idiopathic pulmonary fibrosis (IPF). Subjects with IPF express a significantly higher level of DSP than control subjects. OBJECTIVES Determine potential mechanisms by which DSP is regulated in lung fibrosis. METHODS Matrigel-coated soft and stiff polyacrylamide gels were made to simulate the stiffness of normal and fibrotic lungs. Quantitative chromatin immunoprecipitation and electrophoretic mobility shift assay were used to evaluate transcription factor binding to the DSP promoter. Targeted DNA methylation was achieved by CRISPR (clustered regularly interspaced short palindromic repeats)/dCas9 (deactivated CRISPR-associated protein-9 nuclease)-mediated Dnmt3A (DNA methyltransferase 3A) expression under the guidance of sequence-specific single guide RNAs. MEASUREMENTS AND MAIN RESULTS Stiff matrix promotes DSP gene expression in both human and rodent lung epithelial cells as compared with soft matrix. A conserved region in the proximal DSP promoter is hypermethylated under soft matrix conditions and becomes hypomethylated/demethylated under stiff matrix conditions. Demethylation of this conserved DSP promoter region is associated with transactivation of transcription factor EGR1 (early growth response protein 1), resulting in EGR1-dependent DSP overexpression. Targeted DNA methylation by CRISPR/dCas9/Dnmt3A-mediated epigenome editing blocks EGR1 binding to the DSP promoter and inhibits stiff matrix-induced DSP overexpression. CONCLUSIONS DSP is a matrix stiffness-regulated mechanosensitive gene. CRISPR/dCas9-Dnmt3A-mediated epigenome editing reverses DSP overexpression by reestablishment of the epigenetic control of DSP under the mechanically homeostatic environment. It provides a useful tool for investigations of the functional role of DSP in the pathogenesis of lung fibrosis.
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Affiliation(s)
- Jing Qu
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Lanyan Zhu
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, Hunan, China; and
| | - Zijing Zhou
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, Hunan, China; and
| | - Ping Chen
- Department of Respiratory Medicine, The Second Xiangya Hospital, Central-South University, Changsha, Hunan, China; and
| | - Shuyan Liu
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin, China
| | - Morgan L. Locy
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Victor J. Thannickal
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
| | - Yong Zhou
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama
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Lenin R, Nagy PG, Alli S, Rao VR, Clauss MA, Kompella UB, Gangaraju R. Critical role of endoplasmic reticulum stress in chronic endothelial activation-induced visual deficits in tie2-tumor necrosis factor mice. J Cell Biochem 2018; 119:8460-8471. [PMID: 30054947 DOI: 10.1002/jcb.27072] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2018] [Accepted: 04/26/2018] [Indexed: 12/15/2022]
Abstract
Diabetic retinopathy (DR) is the leading cause of vision loss among working-age adults. The interplay between hyperglycemia and endothelial activation in inducing endoplasmic reticulum (ER) stress pathways and visual deficits in DR is not fully understood. To address this, we used a mouse model of chronic vascular activation using endothelial-specific tumor necrosis factor-α (TNF-α)-expressing (tie2-TNF) mice to induce diabetes with streptozotocin. At 4 weeks post streptozotocin, a significant 2-fold to 10-fold increase in retinal neurovascular inflammatory gene transcript response in tie2-TNF mice was further increased in diabetic tie2-TNF mice. A decrease in visual acuity and scotopic b-wave amplitude in tie2-TNF mice was further accentuated in diabetic tie2-TNF mice and these changes correlated with a multi-fold increase in retinal ER stress markers and a reduction in adherens junctions. Cultured retinal endothelial cells showed a significant decrease in trans-endothelial resistance as well as VE-cadherin expression under TNF-α and high glucose stress. These changes were partly rescued by tauroursodeoxycholic acid, a potent ER stress inhibitor. Taken together, constant endothelial activation induced by TNF-α further exacerbated by hyperglycemia results in activation of ER stress and chronic proinflammation in a feed forward loop ultimately resulting in endothelial junction protein alterations leading to visual deficits in the retina. Inhibition of ER stress and endothelial activation may prove to be a novel therapeutic target in DR.
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Affiliation(s)
- Raji Lenin
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Peter G Nagy
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Shanta Alli
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, Tennessee
| | - Vidhya R Rao
- Department of Molecular Pharmacology and Experimental Therapeutics, Loyola University, Chicago, Illinois
| | - Matthias A Clauss
- Department of Cellular & Integrative Physiology, Indiana University, Indianapolis, Indiana
| | - Uday B Kompella
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Aurora, Colorado
| | - Rajashekhar Gangaraju
- Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, Tennessee.,Department of Anatomy & Neurobiology, University of Tennessee Health Science Center, Memphis, Tennessee
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Opatrilova R, Kubatka P, Caprnda M, Büsselberg D, Krasnik V, Vesely P, Saxena S, Ruia S, Mozos I, Rodrigo L, Kruzliak P, dos Santos KG. Nitric oxide in the pathophysiology of retinopathy: evidences from preclinical and clinical researches. Acta Ophthalmol 2018; 96:222-231. [PMID: 28391624 DOI: 10.1111/aos.13384] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 12/12/2016] [Indexed: 12/11/2022]
Abstract
Retinopathy is the leading cause of blindness and visual disability in working-aged people. The pathogenesis of retinopathy is an actual and still open query. Alterations contributing to oxidative and nitrosative stress, including elevated nitric oxide and superoxide production, changes in the expression of different isoforms of nitric oxide synthase or endogenous antioxidant system, have been implicated in the mechanisms how this ocular disease develops. In addition, it was documented that renin-angiotensin system has been implicated in the progression of retinopathy. Based on comprehensive preclinical and clinical researches in this area, the role of above-mentioned factors in the pathogenesis of diabetic retinopathy, hypertensive retinopathy and ischaemic proliferative retinopathy is reviewed in this study. Moreover, the genetic susceptibility factors involved in the development of the retinopathy and possible strategies that utilize antioxidants as additive therapy are also highlighted here.
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Affiliation(s)
- Radka Opatrilova
- Department of Chemical Drugs; Faculty of Pharmacy; University of Veterinary and Pharmaceutical Sciences; Brno Czech Republic
| | - Peter Kubatka
- Department of Medical Biology; Jessenius Faculty of Medicine; Comenius University in Bratislava; Martin Slovak Republic
- Division of Oncology; Biomedical Center Martin; Jessenius Faculty of Medicine; Comenius University in Bratislava; Martin Slovak Republic
| | - Martin Caprnda
- 2nd Department of Internal Medicine; Faculty of Pharmacy; Comenius University; Bratislava Slovakia
| | | | - Vladimir Krasnik
- Department of Ophthalmology; Faculty of Medicine; Comenius University; Bratislava Slovakia
| | | | - Sandeep Saxena
- Retina Service; Department of Ophthalmology; King George's Medical University; Lucknow India
| | - Surabhi Ruia
- Retina Service; Department of Ophthalmology; King George's Medical University; Lucknow India
| | - Ioana Mozos
- Department of Functional Sciences; “Victor Babes” University of Medicine and Pharmacy; Timisoara Romania
| | - Luis Rodrigo
- Faculty of Medicine; University of Oviedo; Central University Hospital of Asturias (HUCA); Oviedo Spain
| | - Peter Kruzliak
- Department of Chemical Drugs; Faculty of Pharmacy; University of Veterinary and Pharmaceutical Sciences; Brno Czech Republic
| | - Katia Goncalves dos Santos
- Laboratory of Human Molecular Genetics; Universidade Luterana do Brasil; Canoas Brazil
- Experimental and Molecular Cardiovascular Laboratory; Hospital de Clínicas de Porto Alegre; Porto Alegre Brazil
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Broadgate S, Kiire C, Halford S, Chong V. Diabetic macular oedema: under-represented in the genetic analysis of diabetic retinopathy. Acta Ophthalmol 2018; 96 Suppl A111:1-51. [PMID: 29682912 DOI: 10.1111/aos.13678] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 11/21/2017] [Indexed: 12/15/2022]
Abstract
Diabetic retinopathy, a complication of both type 1 and type 2 diabetes, is a complex disease and is one of the leading causes of blindness in adults worldwide. It can be divided into distinct subclasses, one of which is diabetic macular oedema. Diabetic macular oedema can occur at any time in diabetic retinopathy and is the most common cause of vision loss in patients with type 2 diabetes. The purpose of this review is to summarize the large number of genetic association studies that have been performed in cohorts of patients with type 2 diabetes and published in English-language journals up to February 2017. Many of these studies have produced positive associations with gene polymorphisms and diabetic retinopathy. However, this review highlights that within this large body of work, studies specifically addressing a genetic association with diabetic macular oedema, although present, are vastly under-represented. We also highlight that many of the studies have small patient numbers and that meta-analyses often inappropriately combine patient data sets. We conclude that there will continue to be conflicting results and no meaningful findings will be achieved if the historical approach of combining all diabetic retinopathy disease states within patient cohorts continues in future studies. This review also identifies several genes that would be interesting to analyse in large, well-defined cohorts of patients with diabetic macular oedema in future candidate gene association studies.
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Affiliation(s)
- Suzanne Broadgate
- Nuffield Laboratory of Ophthalmology; Nuffield Department of Clinical Neurosciences; University of Oxford; Oxford UK
| | - Christine Kiire
- Nuffield Laboratory of Ophthalmology; Nuffield Department of Clinical Neurosciences; University of Oxford; Oxford UK
- Oxford Eye Hospital; John Radcliffe Hospital; Oxford University NHS Foundation Trust; Oxford UK
| | - Stephanie Halford
- Nuffield Laboratory of Ophthalmology; Nuffield Department of Clinical Neurosciences; University of Oxford; Oxford UK
| | - Victor Chong
- Nuffield Laboratory of Ophthalmology; Nuffield Department of Clinical Neurosciences; University of Oxford; Oxford UK
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29
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Vaicik MK, Blagajcevic A, Ye H, Morse MC, Yang F, Goddi A, Brey EM, Cohen RN. The Absence of Laminin α4 in Male Mice Results in Enhanced Energy Expenditure and Increased Beige Subcutaneous Adipose Tissue. Endocrinology 2018; 159:356-367. [PMID: 28973559 PMCID: PMC5761598 DOI: 10.1210/en.2017-00186] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 07/05/2017] [Indexed: 01/27/2023]
Abstract
Laminin α4 (LAMA4) is located in the extracellular basement membrane that surrounds each individual adipocyte. Here we show that LAMA4 null (Lama4-/-) mice exhibit significantly higher energy expenditure (EE) relative to wild-type (WT) mice at room temperature and when exposed to a cold challenge, despite similar levels of food intake and locomotor activity. The Lama4-/- mice are resistant to age- and diet-induced obesity. Expression of uncoupling protein 1 is higher in subcutaneous white adipose tissue of Lama4-/- mice relative to WT animals on either a chow diet or a high-fat diet. In contrast, uncoupling protein 1 expression was not increased in brown adipose tissue. Lama4-/- mice exhibit significantly improved insulin sensitivity compared with WT mice, suggesting improved metabolic function. Overall, these data provide critical evidence for a role of the basement membrane in EE, weight gain, and systemic insulin sensitivity.
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Affiliation(s)
- Marcella K. Vaicik
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois 60141
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, Illinois 60616
| | - Alen Blagajcevic
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Chicago, Chicago, Illinois 60637
| | - Honggang Ye
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Chicago, Chicago, Illinois 60637
| | - Mallory C. Morse
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Chicago, Chicago, Illinois 60637
| | - Feipeng Yang
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, Illinois 60616
| | - Anna Goddi
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Chicago, Chicago, Illinois 60637
| | - Eric M. Brey
- Research Service, Edward Hines Jr. VA Hospital, Hines, Illinois 60141
- Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, Illinois 60616
| | - Ronald N. Cohen
- Section of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Chicago, Chicago, Illinois 60637
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30
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Halfter W, Moes S, Asgeirsson DO, Halfter K, Oertle P, Melo Herraiz E, Plodinec M, Jenoe P, Henrich PB. Diabetes-related changes in the protein composition and the biomechanical properties of human retinal vascular basement membranes. PLoS One 2017; 12:e0189857. [PMID: 29284024 PMCID: PMC5746242 DOI: 10.1371/journal.pone.0189857] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Accepted: 12/04/2017] [Indexed: 12/18/2022] Open
Abstract
Basement membranes (BMs) are specialized sheets of extracellular matrix that outline epithelial cell layers, muscle fibers, blood vessels, and peripheral nerves. A well-documented histological hallmark of progressing diabetes is a major increase in vascular BM thickness. In order to investigate whether this structural change is accompanied by a change in the protein composition, we compared the proteomes of retinal vascular BMs from diabetic and non-diabetic donors by using LC-MS/MS. Data analysis showed that seventeen extracellular matrix (ECM)-associated proteins were more abundant in diabetic than non-diabetic vascular BMs. Four ECM proteins were more abundant in non-diabetic than in diabetic BMs. Most of the over-expressed proteins implicate a complement-mediated chronic inflammatory process in the diabetic retinal vasculature. We also found an up-regulation of norrin, a protein that is known to promote vascular proliferation, possibly contributing to the vascular remodeling during diabetes. Many of the over-expressed proteins were localized to microvascular aneurisms. Further, the overall stoichiometry of proteins was changed, such that the relative abundance of collagens in BMs from diabetic patients was higher than normal. Biomechanical measurements of vascular BM flat mounts using AFM showed that their outer surface was softer than normal.
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Affiliation(s)
- Willi Halfter
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Suzette Moes
- Proteomics Core Facility, Biocenter of the University of Basel, Basel, Switzerland
| | - Daphne O. Asgeirsson
- Biocenter and the Swiss Nanoscience Institute, University of Basel, Basel, Switzerland
| | - Kathrin Halfter
- Institute of Medical Informatics, Biometry and Epidemiology, Maximilian University Munich, Munich, Germany
| | - Philipp Oertle
- Biocenter and the Swiss Nanoscience Institute, University of Basel, Basel, Switzerland
| | - Esther Melo Herraiz
- Biocenter and the Swiss Nanoscience Institute, University of Basel, Basel, Switzerland
| | - Marija Plodinec
- Biocenter and the Swiss Nanoscience Institute, University of Basel, Basel, Switzerland
| | - Paul Jenoe
- Proteomics Core Facility, Biocenter of the University of Basel, Basel, Switzerland
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Chen J, Ren J, Loo WTY, Hao L, Wang M. Lysyl oxidases expression and histopathological changes of the diabetic rat nephron. Mol Med Rep 2017; 17:2431-2441. [PMID: 29207131 PMCID: PMC5783488 DOI: 10.3892/mmr.2017.8182] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 11/06/2017] [Indexed: 02/05/2023] Open
Abstract
Diabetic nephropathy (DN) is a major complication of diabetes, the accumulation of extracellular matrix (ECM) is considered an indication of nephropathological changes. Lysyl oxidases (LOXs) are also associated with ECM. However, the majority of studies on LOXs have focused on their potential role in renal fibrogenesis and there has no examination of LOXs expression or the correlation with histopathological changes of DN, including glomerular basement membrane (GBM) thickening and glomerulosclerosis. In this study, the association between histological changes and LOXs was explored using a type 2 diabetes model of male Zucker diabetic fatty rats. The expression of LOX and lysyl oxidase-like 1 to 3 (LOXL1 to 3) levels were evaluated by immunohistochemical staining. The expression levels of LOX and LOXL2 in the kidney tissue in the diabetic group were significantly higher compared with those of the control group, but LOXL1 and LOXL3 expression levels were not significantly different between the two groups. These results indicated that LOXL2 and LOX may be critical factors involved in the progression of DN.
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Affiliation(s)
- Jun Chen
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Jie Ren
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Wings T Y Loo
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Kowloon, Hong Kong 999077, P.R. China
| | - Liang Hao
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, P.R. China
| | - Min Wang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan 610041, P.R. China
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32
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Biomechanics of human parietal pleura in uniaxial extension. J Mech Behav Biomed Mater 2017; 75:330-335. [DOI: 10.1016/j.jmbbm.2017.07.044] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2017] [Revised: 07/21/2017] [Accepted: 07/28/2017] [Indexed: 12/17/2022]
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Vimentin knockout results in increased expression of sub-endothelial basement membrane components and carotid stiffness in mice. Sci Rep 2017; 7:11628. [PMID: 28912461 PMCID: PMC5599644 DOI: 10.1038/s41598-017-12024-z] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 09/01/2017] [Indexed: 12/11/2022] Open
Abstract
Intermediate filaments are involved in stress-related cell mechanical properties and in plasticity via the regulation of focal adhesions (FAs) and the actomyosin network. We investigated whether vimentin regulates endothelial cells (ECs) and vascular smooth muscle cells (SMCs) and thereby influences vasomotor tone and arterial stiffness. Vimentin knockout mice (Vim−/−) exhibited increased expression of laminin, fibronectin, perlecan, collagen IV and VE-cadherin as well as von Willebrand factor deposition in the subendothelial basement membrane. Smooth muscle (SM) myosin heavy chain, α-SM actin and smoothelin were decreased in Vim−/− mice. Electron microscopy revealed a denser endothelial basement membrane and increased SM cell-matrix interactions. Integrin αv, talin and vinculin present in FAs were increased in Vim−/− mice. Phosphorylated FA kinase and its targets Src and ERK1/2 were elevated in Vim−/− mice. Knockout of vimentin, but not of synemin, resulted in increased carotid stiffness and contractility and endothelial dysfunction, independently of blood pressure and the collagen/elastin ratio. The increase in arterial stiffness in Vim−/− mice likely involves vasomotor tone and endothelial basement membrane organization changes. At the tissue level, the results show the implication of FAs both in ECs and vascular SMCs in the role of vimentin in arterial stiffening.
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Kim D, Mecham RP, Trackman PC, Roy S. Downregulation of Lysyl Oxidase Protects Retinal Endothelial Cells From High Glucose-Induced Apoptosis. Invest Ophthalmol Vis Sci 2017; 58:2725-2731. [PMID: 28538980 PMCID: PMC5444550 DOI: 10.1167/iovs.16-21340] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Purpose To investigate the effect of reducing high glucose (HG)-induced lysyl oxidase (LOX) overexpression and increased activity on retinal endothelial cell apoptosis. Methods Rat retinal endothelial cells (RRECs) were grown in normal (N) or HG (30 mM glucose) medium for 7 days. In parallel, RRECs were grown in HG medium and transfected with LOX small interfering RNA (siRNA), scrambled siRNA as control, or exposed to β-aminopropionitrile (BAPN), a LOX inhibitor. LOX expression, AKT activation, and caspase-3 activity were determined by Western blot (WB) analysis and apoptosis by differential dye staining assay. Moreover, to determine whether diabetes-induced LOX overexpression alters AKT activation and promotes apoptosis, changes in LOX expression, AKT phosphorylation, caspase-3 activation, and Bax expression were assessed in retinas of streptozotocin (STZ)-induced diabetic mice and LOX heterozygous knockout (LOX+/-) mice. Results WB analysis indicated significant LOX overexpression and reduced AKT activation under HG condition in RRECs. Interestingly, when cells grown in HG were transfected with LOX siRNA or exposed to BAPN, the number of apoptotic cells was significantly decreased concomitant with increased AKT phosphorylation. Diabetic mouse retinas exhibited LOX overexpression, decreased AKT phosphorylation, and increased Bax and caspase-3 activation compared to values in nondiabetic mice. In LOX+/- mice, reduced LOX levels were observed with increased AKT activity, and reduced Bax and caspase-3 activity. Furthermore, decreased levels of LOX in the LOX+/- mice was protective against diabetes-induced apoptosis. Conclusions Findings from this study indicate that preventing LOX overexpression may be protective against HG-induced apoptosis in retinal vascular cells associated with diabetic retinopathy.
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Affiliation(s)
- Dongjoon Kim
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States 2Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
| | - Robert P Mecham
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, United States
| | - Philip C Trackman
- Department of Molecular and Cell Biology, Boston University Henry M. Goldman School of Dental Medicine, Boston, Massachusetts, United States
| | - Sayon Roy
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, United States 2Department of Ophthalmology, Boston University School of Medicine, Boston, Massachusetts, United States
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Du P, Suhaeri M, Ha SS, Oh SJ, Kim SH, Park K. Human lung fibroblast-derived matrix facilitates vascular morphogenesis in 3D environment and enhances skin wound healing. Acta Biomater 2017; 54:333-344. [PMID: 28351680 DOI: 10.1016/j.actbio.2017.03.035] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 03/23/2017] [Accepted: 03/24/2017] [Indexed: 10/19/2022]
Abstract
Extracellular matrix (ECM) is crucial to many aspects of vascular morphogenesis and maintenance of vasculature function. Currently the recapitulation of angiogenic ECM microenvironment is still challenging, due mainly to its diverse components and complex organization. Here we investigate the angiogenic potential of human lung fibroblast-derived matrix (hFDM) in creating a three-dimensional (3D) vascular construct. hFDM was obtained via decellularization of in vitro cultured human lung fibroblasts and analyzed via immunofluorescence staining and ELISA, which detect multiple ECM macromolecules and angiogenic growth factors (GFs). Human umbilical vein endothelial cells (HUVECs) morphology was more elongated and better proliferative on hFDM than on gelatin-coated substrate. To prepare 3D construct, hFDM is collected, quantitatively analyzed, and incorporated in collagen hydrogel (Col) with HUVECs. Capillary-like structure (CLS) formation at 7day was significantly better with the groups containing higher doses of hFDM compared to the Col group (control). Moreover, the group (Col/hFDM/GFs) with both hFDM and angiogenic GFs (VEGF, bFGF, SDF-1) showed the synergistic activity on CLS formation and found much larger capillary lumen diameters with time. Further analysis of hFDM via angiogenesis antibody array kit reveals abundant biochemical cues, such as angiogenesis-related cytokines, GFs, and proteolytic enzymes. Significantly up-regulated expression of VE-cadherin and ECM-specific integrin subunits was also noticed in Col/hFDM/GFs. In addition, transplantation of Col/hFMD/GFs with HUVECs in skin wound model presents more effective re-epithelialization, many regenerated hair follicles, better transplanted cells viability, and advanced neovascularization. We believe that current system is a very promising platform for 3D vasculature construction in vitro and for cell delivery toward therapeutic applications in vivo. STATEMENT OF SIGNIFICANCE Functional 3D vasculature construction in vitro is still challenging due to the difficulty of recapitulating the complex angiogenic extracellular matrix (ECM) environment. Herein, we present a simple and practical method to create an angiogenic 3D environment via incorporation of human lung fibroblast-derived matrix (hFDM) into collagen hydrogel. We found that hFDM offers a significantly improved angiogenic microenvironment for HUVECs on 2D substrates and in 3D construct. A synergistic effect of hFDM and angiogenic growth factors has been well confirmed in 3D condition. The prevascularized 3D collagen constructs also facilitate skin wound healing. We believe that current system should be a convenient and powerful platform in engineering 3D vasculature in vitro, and in delivering cells for therapeutic purposes in vivo.
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Caceres PS, Benedicto I, Lehmann GL, Rodriguez-Boulan EJ. Directional Fluid Transport across Organ-Blood Barriers: Physiology and Cell Biology. Cold Spring Harb Perspect Biol 2017; 9:a027847. [PMID: 28003183 PMCID: PMC5334253 DOI: 10.1101/cshperspect.a027847] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Directional fluid flow is an essential process for embryo development as well as for organ and organism homeostasis. Here, we review the diverse structure of various organ-blood barriers, the driving forces, transporters, and polarity mechanisms that regulate fluid transport across them, focusing on kidney-, eye-, and brain-blood barriers. We end by discussing how cross talk between barrier epithelial and endothelial cells, perivascular cells, and basement membrane signaling contribute to generate and maintain organ-blood barriers.
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Affiliation(s)
- Paulo S Caceres
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
| | - Ignacio Benedicto
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
| | - Guillermo L Lehmann
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
| | - Enrique J Rodriguez-Boulan
- Margaret Dyson Vision Research Institute, Department of Ophthalmology, Weill Cornell Medical College, New York, New York 10065
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Mohan RR, Cabrera AP, Harrison RES, Gorham RD, Johnson LV, Ghosh K, Morikis D. Peptide redesign for inhibition of the complement system: Targeting age-related macular degeneration. Mol Vis 2016; 22:1280-1290. [PMID: 27829783 PMCID: PMC5082644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 10/24/2016] [Indexed: 11/30/2022] Open
Abstract
PURPOSE To redesign a complement-inhibiting peptide with the potential to become a therapeutic for dry and wet age-related macular degeneration (AMD). METHODS We present a new potent peptide (Peptide 2) of the compstatin family. The peptide is developed by rational design, based on a mechanistic binding hypothesis, and structural and physicochemical properties derived from molecular dynamics (MD) simulation. The inhibitory activity, efficacy, and solubility of Peptide 2 are evaluated using a hemolytic assay, a human RPE cell-based assay, and ultraviolet (UV) absorption properties, respectively, and compared to the respective properties of its parent peptide (Peptide 1). RESULTS The sequence of Peptide 2 contains an arginine-serine N-terminal extension (a characteristic of parent Peptide 1) and a novel 8-polyethylene glycol (PEG) block C-terminal extension. Peptide 2 has significantly improved aqueous solubility compared to Peptide 1 and comparable complement inhibitory activity. In addition, Peptide 2 is more efficacious in inhibiting complement activation in a cell-based model that mimics the pathobiology of dry AMD. CONCLUSIONS We have designed a new peptide analog of compstatin that combines N-terminal polar amino acid extensions and C-terminal PEGylation extensions. This peptide demonstrates significantly improved aqueous solubility and complement inhibitory efficacy, compared to the parent peptide. The new peptide overcomes the aggregation limitation for clinical translation of previous compstatin analogs and is a candidate to become a therapeutic for the treatment of AMD.
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Affiliation(s)
- Rohith R. Mohan
- Department of Bioengineering, University of California, Riverside, CA
| | - Andrea P. Cabrera
- Department of Bioengineering, University of California, Riverside, CA
| | | | - Ronald D. Gorham
- Department of Bioengineering, University of California, Riverside, CA
| | - Lincoln V. Johnson
- Center for the Study of Macular Degeneration, Neuroscience Research Institute, University of California, Santa Barbara, CA
| | - Kaustabh Ghosh
- Department of Bioengineering, University of California, Riverside, CA
| | - Dimitrios Morikis
- Department of Bioengineering, University of California, Riverside, CA
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Scott HA, Quach B, Yang X, Ardekani S, Cabrera AP, Wilson R, Messaoudi-Powers I, Ghosh K. Matrix stiffness exerts biphasic control over monocyte-endothelial adhesion via Rho-mediated ICAM-1 clustering. Integr Biol (Camb) 2016; 8:869-78. [PMID: 27444067 DOI: 10.1039/c6ib00084c] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Leukocyte-endothelial adhesion is a critical early step in chronic vascular inflammation associated with diabetes, emphysema, and aging. Importantly, these conditions are also marked by abnormal subendothelial matrix crosslinking (stiffness). Yet, whether and how abnormal matrix stiffness contributes to leukocyte-endothelial adhesion remains poorly understood. Using a co-culture of human monocytic cells and human microvascular endothelial cells (ECs) grown on matrices of tunable stiffness, we demonstrate that matrix stiffness exerts biphasic control over monocyte-EC adhesion, with both matrix softening and stiffening eliciting a two-fold increase in this adhesive interaction. This preferential endothelial adhesivity on softer and stiffer matrices was consistent with a significant increase in α-actinin-4-associated endothelial ICAM-1 clustering, a key determinant of monocyte-EC adhesion. Further, the enhanced ICAM-1 clustering on soft and stiff matrices correlated strongly with an increase in Rho activity and ROCK2 expression. Importantly, inhibition of Rho/ROCK activity blocked the effects of abnormal matrix stiffness on ICAM-1 clustering and monocyte-EC adhesion. Thus, these findings implicate matrix stiffness-dependent ICAM-1 clustering as an important regulator of vascular inflammation and provide the rationale for closely examining mechanotransduction pathways as new molecular targets for anti-inflammatory therapy.
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Affiliation(s)
- Harry A Scott
- Department of Bioengineering, University of California Riverside, 900 University Avenue, MSE 207, Riverside, CA 92521, USA.
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