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Ferreira-Santos L, Martinez-Lemus LA, Padilla J. Sitting leg vasculopathy: potential adaptations beyond the endothelium. Am J Physiol Heart Circ Physiol 2024; 326:H760-H771. [PMID: 38241008 PMCID: PMC11221807 DOI: 10.1152/ajpheart.00489.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 12/27/2023] [Accepted: 01/18/2024] [Indexed: 02/29/2024]
Abstract
Increased sitting time, the most common form of sedentary behavior, is an independent risk factor for all-cause and cardiovascular disease mortality; however, the mechanisms linking sitting to cardiovascular risk remain largely elusive. Studies over the last decade have led to the concept that excessive time spent in the sitting position and the ensuing reduction in leg blood flow-induced shear stress cause endothelial dysfunction. This conclusion has been mainly supported by studies using flow-mediated dilation in the lower extremities as the measured outcome. In this review, we summarize evidence from classic studies and more recent ones that collectively support the notion that prolonged sitting-induced leg vascular dysfunction is likely also attributable to changes occurring in vascular smooth muscle cells (VSMCs). Indeed, we provide evidence that prolonged constriction of resistance arteries can lead to modifications in the structural characteristics of the vascular wall, including polymerization of actin filaments in VSMCs and inward remodeling, and that these changes manifest in a time frame that is consistent with the vascular changes observed with prolonged sitting. We expect this review will stimulate future studies with a focus on VSMC cytoskeletal remodeling as a potential target to prevent the detrimental vascular ramifications of too much sitting.
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Affiliation(s)
| | - Luis A Martinez-Lemus
- NextGen Precision Health, University of Missouri, Columbia, Missouri, United States
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, United States
- Center for Precision Medicine, Department of Medicine, University of Missouri, Columbia, Missouri, United States
| | - Jaume Padilla
- NextGen Precision Health, University of Missouri, Columbia, Missouri, United States
- Department of Nutrition and Exercise Physiology, University of Missouri, Columbia, Missouri, United States
- Harry S. Truman Memorial Veterans' Hospital, Columbia, Missouri, United States
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2
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Murphy AR, Allenby MC. In vitro microvascular engineering approaches and strategies for interstitial tissue integration. Acta Biomater 2023; 171:114-130. [PMID: 37717711 DOI: 10.1016/j.actbio.2023.09.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 09/10/2023] [Accepted: 09/12/2023] [Indexed: 09/19/2023]
Abstract
The increasing gap between clinical demand for tissue or organ transplants and the availability of donated tissue highlights the emerging opportunities for lab-grown or synthetically engineered tissue. While the field of tissue engineering has existed for nearly half a century, its clinical translation remains unrealised, in part, due to a limited ability to engineer sufficient vascular supply into fabricated tissue, which is necessary to enable nutrient and waste exchange, prevent cellular necrosis, and support tissue proliferation. Techniques to develop anatomically relevant, functional vascular networks in vitro have made significant progress in the last decade, however, the challenge now remains as to how best incorporate these throughout dense parenchymal tissue-like structures to address diffusion-limited development and allow for the fabrication of large-scale vascularised tissue. This review explores advances made in the laboratory engineering of vasculature structures and summarises recent attempts to integrate vascular networks together with sophisticated in vitro avascular tissue and organ-like structures. STATEMENT OF SIGNIFICANCE: The ability to grow full scale, functional tissue and organs in vitro is primarily limited by an inability to adequately diffuse oxygen and nutrients throughout developing cellularised structures, which generally results from the absence of perfusable vessel networks. Techniques to engineering both perfusable vascular networks and avascular miniaturised organ-like structures have recently increased in complexity, sophistication, and physiological relevance. However, integrating these two essential elements into a single functioning vascularised tissue structure represents a significant spatial and temporal engineering challenge which is yet to be surmounted. Here, we explore a range of vessel morphogenic phenomena essential for tissue-vascular co-development, as well as evaluate a range of recent noteworthy approaches for generating vascularised tissue products in vitro.
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Affiliation(s)
- A R Murphy
- School of Chemical Engineering, Faculty of Engineering, Architecture and Information Technology, The University of Queensland, St Lucia, QLD 4100, Australia
| | - M C Allenby
- School of Chemical Engineering, Faculty of Engineering, Architecture and Information Technology, The University of Queensland, St Lucia, QLD 4100, Australia; Centre for Biomedical Technologies, School of Medical, Mechanical and Process Engineering, Faculty of Engineering, Queensland University of Technology, Kelvin Grove, QLD 4059, Australia.
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3
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Ojha KR, Kim H, Padgham S, Hopkins L, Zamen RJ, Chattopadhyay A, Han G, Milewicz DM, Massett MP, Trache A. Smooth Muscle-Alpha Actin R149C Pathogenic Variant Downregulates Integrin Recruitment at Cell-Matrix Adhesions and Decreases Cellular Contractility. Int J Mol Sci 2023; 24:9616. [PMID: 37298565 PMCID: PMC10253315 DOI: 10.3390/ijms24119616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 05/21/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
Thoracic aortic aneurysm is found in patients with ACTA2 pathogenic variants. ACTA2 missense variants are associated with impaired aortic smooth muscle cell (SMC) contraction. This study tested the hypothesis that the Acta2R149C/+ variant alters actin isoform expression and decreases integrin recruitment, thus, reducing aortic contractility. Stress relaxation measurements in thoracic aortic rings showed two functional regimes with a reduction of stress relaxation in the aorta from Acta2R149C/+ mice at low tension, but not at high tension values. Contractile responses to phenylephrine and potassium chloride were 50% lower in Acta2R149C/+ mice than in wild-type (WT) mice. Additionally, SMC were immunofluorescently labeled for specific proteins and imaged by confocal or total internal reflection fluorescence microscopy. The quantification of protein fluorescence of Acta2R149C/+ SMC showed a downregulation in smooth muscle α-actin (SMα-actin) and a compensatory upregulation of smooth muscle γ-actin (SMγ-actin) compared to WT cells. These results suggest that downregulation of SMα-actin leads to reduced SMC contractility, while upregulation of SMγ-actin may lead to increased SMC stiffness. Decreased α5β1 and α2β1 integrin recruitment at cell-matrix adhesions further reduce the ability of mutant cells to participate in cell-matrix crosstalk. Collectively, the results suggest that mutant Acta2R149C/+ aortic SMC have reduced contractility and interaction with the matrix, which are potential long-term contributing factors to thoracic aortic aneurysms.
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Affiliation(s)
- Krishna R. Ojha
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA
| | - Hyoseon Kim
- Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, TX 79409, USA
| | - Samuel Padgham
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA
| | - Laura Hopkins
- Department of Epidemiology and Statistics, Texas A&M University Health Science Center, College Station, TX 77843, USA
| | - Robert J. Zamen
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Abhijnan Chattopadhyay
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Gang Han
- Department of Epidemiology and Statistics, Texas A&M University Health Science Center, College Station, TX 77843, USA
| | - Dianna M. Milewicz
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA
| | - Michael P. Massett
- Department of Kinesiology and Sport Management, Texas Tech University, Lubbock, TX 79409, USA
| | - Andreea Trache
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
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4
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Pang X, He X, Qiu Z, Zhang H, Xie R, Liu Z, Gu Y, Zhao N, Xiang Q, Cui Y. Targeting integrin pathways: mechanisms and advances in therapy. Signal Transduct Target Ther 2023; 8:1. [PMID: 36588107 PMCID: PMC9805914 DOI: 10.1038/s41392-022-01259-6] [Citation(s) in RCA: 146] [Impact Index Per Article: 146.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/14/2022] [Accepted: 11/21/2022] [Indexed: 01/03/2023] Open
Abstract
Integrins are considered the main cell-adhesion transmembrane receptors that play multifaceted roles as extracellular matrix (ECM)-cytoskeletal linkers and transducers in biochemical and mechanical signals between cells and their environment in a wide range of states in health and diseases. Integrin functions are dependable on a delicate balance between active and inactive status via multiple mechanisms, including protein-protein interactions, conformational changes, and trafficking. Due to their exposure on the cell surface and sensitivity to the molecular blockade, integrins have been investigated as pharmacological targets for nearly 40 years, but given the complexity of integrins and sometimes opposite characteristics, targeting integrin therapeutics has been a challenge. To date, only seven drugs targeting integrins have been successfully marketed, including abciximab, eptifibatide, tirofiban, natalizumab, vedolizumab, lifitegrast, and carotegrast. Currently, there are approximately 90 kinds of integrin-based therapeutic drugs or imaging agents in clinical studies, including small molecules, antibodies, synthetic mimic peptides, antibody-drug conjugates (ADCs), chimeric antigen receptor (CAR) T-cell therapy, imaging agents, etc. A serious lesson from past integrin drug discovery and research efforts is that successes rely on both a deep understanding of integrin-regulatory mechanisms and unmet clinical needs. Herein, we provide a systematic and complete review of all integrin family members and integrin-mediated downstream signal transduction to highlight ongoing efforts to develop new therapies/diagnoses from bench to clinic. In addition, we further discuss the trend of drug development, how to improve the success rate of clinical trials targeting integrin therapies, and the key points for clinical research, basic research, and translational research.
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Affiliation(s)
- Xiaocong Pang
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Xu He
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Zhiwei Qiu
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Hanxu Zhang
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Ran Xie
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Zhiyan Liu
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Yanlun Gu
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Nan Zhao
- grid.411472.50000 0004 1764 1621Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034 Beijing, China ,grid.411472.50000 0004 1764 1621Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191 Beijing, China
| | - Qian Xiang
- Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034, Beijing, China. .,Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191, Beijing, China.
| | - Yimin Cui
- Department of Pharmacy, Peking University First Hospital, Xishiku Street, Xicheng District, 100034, Beijing, China. .,Institute of Clinical Pharmacology, Peking University First Hospital, Xueyuan Road 38, Haidian District, 100191, Beijing, China.
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Ojha KR, Shin SY, Padgham S, Leon Olmedo F, Guo B, Han G, Woodman C, Trache A. Age-Associated Dysregulation of Integrin Function in Vascular Smooth Muscle. Front Physiol 2022; 13:913673. [PMID: 35874532 PMCID: PMC9301045 DOI: 10.3389/fphys.2022.913673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 06/06/2022] [Indexed: 11/13/2022] Open
Abstract
Arterial aging results in a progressive reduction in elasticity of the vessel wall and an impaired ability of aged blood vessels to control local blood flow and pressure. Recently, a new concept has emerged that the stiffness and decreased contractility of vascular smooth muscle (VSM) cells are important contributors to age-induced arterial dysfunction. This study investigated the hypothesis that aging alters integrin function in a matrix stiffness-dependent manner, which contributes to decreased VSM contractility in aged soleus muscle feed arteries (SFA). The effect of RGD-binding integrins on contractile function of cannulated SFA isolated from young (4 months) and old (24 months) Fischer 344 rats was assessed by measuring constrictor responses to norepinephrine, phenylephrine, and angiotensin II. Results indicated that constrictor responses in presence of RGD were impaired in old compared to young SFA. VSM cells isolated from young and old SFA were used for functional experiments using atomic force microscopy and high-resolution imaging. Aging was associated with a modulation of integrin β1 recruitment at cell-matrix adhesions that was matrix and substrate stiffness dependent. Our data showed that substrate stiffening drives altered integrin β1 expression in aging, while soft substrates abolish age-induced differences in overall integrin β1 expression. In addition, substrate stiffness and matrix composition contribute to the modulation of SMα-actin cytoskeleton architecture with soft substrates reducing age effects. Our results provide new insights into age-induced structural changes at VSM cell level that translates to decreased functionality of aged resistance soleus feed arteries.
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Affiliation(s)
- Krishna Raj Ojha
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Song Yi Shin
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, United States
| | - Samuel Padgham
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX, United States
| | - Frida Leon Olmedo
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
| | - Bohong Guo
- Department of Epidemiology and Statistics, Texas A&M University Health Science Center, College Station, TX, United States
| | - Gang Han
- Department of Epidemiology and Statistics, Texas A&M University Health Science Center, College Station, TX, United States
| | - Christopher Woodman
- Department of Health and Kinesiology, Texas A&M University, College Station, TX, United States
| | - Andreea Trache
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX, United States
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, United States
- *Correspondence: Andreea Trache,
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6
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Yang Y, Nourian Z, Li M, Sun Z, Zhang L, Davis MJ, Meininger GA, Wu J, Braun AP, Hill MA. Modification of Fibronectin by Non-Enzymatic Glycation Impairs K + Channel Function in Rat Cerebral Artery Smooth Muscle Cells. Front Physiol 2022; 13:871968. [PMID: 35832482 PMCID: PMC9272009 DOI: 10.3389/fphys.2022.871968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
Fibronectin (FN) enhances K+ channel activity by integrin-mediated mechanisms. As vascular smooth muscle (VSM) K+ channels mediate vasodilation, we hypothesized that modification of fibronectin, via advanced non-enzymatic glycation, would alter signaling of this extracellular matrix protein through these channels. Bovine FN (1 mg/ml) was glycated (gFN) for 5 days using methylglyoxal (50 mM), and albumin was similarly glycated as a non-matrix protein control. VSM cells were isolated from rat cerebral arteries for measurement of macroscopic K+ channel activity using whole cell patch clamp methodology. Pharmacological inhibitors, iberiotoxin (0.1 μM) and 4-aminopyridine (0.1 mM), were used to identify contributions of large-conductance, Ca2+-activated, K+ channels and voltage-gated K+ channels, respectively. Compared with baseline, native FN enhanced whole cell K+ current in a concentration-dependent manner, whereas gFN inhibited basal current. Furthermore, native albumin did not enhance basal K+ current, but the glycated form (gAlb) caused inhibition. gFN was shown to impair both the Kv and BKCa components of total macroscopic K+ current. Anti-integrin α5 and β1 antibodies attenuated the effects of both FN and gFN on macroscopic K+ current at +70 mV. Consistent with an action on BKCa activity, FN increased, whereas gFN decreased the frequency of spontaneous transient outward current (STOCs). In contrast, gAlb inhibited whole cell K+ current predominantly through Kv, showing little effect on STOCs. A function-blocking, anti-RAGE antibody partially reversed the inhibitory effects of gFN, suggesting involvement of this receptor. Further, gFN caused production of reactive oxygen species (ROS) by isolated VSMCs as revealed by the fluorescent indicator, DHE. Evoked ROS production was attenuated by the RAGE blocking antibody. Collectively, these studies identify ion channel-related mechanisms (integrin and ROS-mediated) by which protein glycation may modify VSMC function.
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Affiliation(s)
- Yan Yang
- Dalton Cardiovascular Research Center, Columbia, MO, United States
| | - Zahra Nourian
- Dalton Cardiovascular Research Center, Columbia, MO, United States
| | - Min Li
- Dalton Cardiovascular Research Center, Columbia, MO, United States
| | - Zhe Sun
- Dalton Cardiovascular Research Center, Columbia, MO, United States
| | | | - Michael J. Davis
- Dalton Cardiovascular Research Center, Columbia, MO, United States
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Gerald A. Meininger
- Dalton Cardiovascular Research Center, Columbia, MO, United States
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Jianbo Wu
- Southwest Medical University, Luzhou, China
| | - Andrew P. Braun
- Department of Physiology and Pharmacology, University of Calgary, Calgary, AB, Canada
| | - Michael A. Hill
- Dalton Cardiovascular Research Center, Columbia, MO, United States
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
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7
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Mironova GY, Mazumdar N, Hashad AM, El-Lakany MA, Welsh DG. Defining a Role of NADPH Oxidase in Myogenic Tone Development. Microcirculation 2022; 29:e12756. [PMID: 35289024 DOI: 10.1111/micc.12756] [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: 08/10/2021] [Revised: 03/07/2022] [Accepted: 03/09/2022] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The myogenic response sets the foundation for blood flow control. Recent findings suggest a role for G-protein coupled receptors (GPCR) and signaling pathways tied to the generation of reactive oxygen species (ROS). In this regard, this study ascertained the impact of NADPH oxidase (Nox) on myogenic tone in rat cerebral resistance arteries. METHODS The study employed real-time qPCR (RT-qPCR), pressure myography, and immunohistochemistry. RESULTS Gq blockade abolished myogenic tone in rat cerebral arteries, linking GPCR to mechanosensation. Subsequent work revealed that general (TEMPOL) and mitochondrial specific (MitoTEMPO) ROS scavengers had little impact on myogenic tone, whereas apocynin, a broad spectrum Nox inhibitor, initiated transient dilation. RT-qPCR revealed Nox1 and Nox2 mRNA expression in smooth muscle cells. Pressure myography defined Nox1 rather than Nox2 is facilitating myogenic tone. We rationalized that Nox1-generated ROS was initiating this response by impairing the ability of the CaV 3.2 channel to elicit negative feedback via BKCa . This hypothesis was confirmed in functional experiments. The proximity ligation assay further revealed that Nox1 and CaV 3.2 colocalize within 40 nm of one another. CONCLUSIONS Our data highlight that vascular pressurization augments Nox1 activity and ensuing ROS production facilitates myogenic tone by limiting Ca2+ influx via CaV 3.2.
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Affiliation(s)
- Galina Yu Mironova
- Robarts Research Institute and Dept. of Physiology & Pharmacology, The University of Western Ontario, London, Ontario, Canada
| | - Neil Mazumdar
- Robarts Research Institute and Dept. of Physiology & Pharmacology, The University of Western Ontario, London, Ontario, Canada
| | - Ahmed M Hashad
- Robarts Research Institute and Dept. of Physiology & Pharmacology, The University of Western Ontario, London, Ontario, Canada.,Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mohammed A El-Lakany
- Robarts Research Institute and Dept. of Physiology & Pharmacology, The University of Western Ontario, London, Ontario, Canada.,Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Donald G Welsh
- Robarts Research Institute and Dept. of Physiology & Pharmacology, The University of Western Ontario, London, Ontario, Canada
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Yu Y, Li Y, Peng H, Song Q, Da X, Li H, He Z, Ren X, Xu C, Yao Y, Wang QK. Angiogenic factor AGGF1 Blocks Neointimal Formation after Vascular Injury via Interaction with Integrin α7 on Vascular Smooth Muscle Cells. J Biol Chem 2022; 298:101759. [PMID: 35202649 PMCID: PMC8968644 DOI: 10.1016/j.jbc.2022.101759] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 02/11/2022] [Accepted: 02/12/2022] [Indexed: 11/29/2022] Open
Abstract
Angiogenic factor AGGF1 (AngioGenic factor with G-patch and FHA (Forkhead-Associated) domain 1) blocks neointimal formation (formation of a new or thickened layer of arterial intima) after vascular injury by regulating phenotypic switching of vascular smooth muscle cells (VSMCs). However, the AGGF1 receptor on VSMCs and the underlying molecular mechanisms of its action are unknown. In this study, we used functional analysis of serial AGGF1 deletions to reveal the critical AGGF1 domain involved in VSMC phenotypic switching. This domain was required for VSMC phenotypic switching, proliferation, cell cycle regulation, and migration, as well as the regulation of cell cycle inhibitors cyclin D, p27, and p21. This domain also contains an RDDAPAS motif via which AGGF1 interacts with integrin α7 (ITGA7), but not α8. In addition, we show that AGGF1 enhanced the expression of contractile markers MYH11, α-SMA, and SM22 and inhibited MEK1/2, ERK1/2, and ELK phosphorylation in VSMCs, and that these effects were inhibited by knockdown of ITGA7, but not by knockdown of ITGA8. In vivo, deletion of the VSMC phenotypic switching domain in mice with vascular injury inhibited the functions of AGGF1 in upregulating α-SMA and SM22, inhibiting MEK1/2, ERK1/2, and ELK phosphorylation, in VSMC proliferation, and in blocking neointimal formation. Finally, we show the inhibitory effect of AGGF1 on neointimal formation was blocked by lentivirus-delivered shRNA targeting ITGA7. Our data demonstrate that AGGF1 interacts with its receptor integrin α7 on VSMCs, and this interaction is required for AGGF1 signaling in VSMCs and for attenuation of neointimal formation after vascular injury.
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Affiliation(s)
- Yubing Yu
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Yong Li
- College of Biotechnology, Guilin Medical University
| | - Huixin Peng
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Qixue Song
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Xingwen Da
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Hui Li
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Zuhan He
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Xiang Ren
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China
| | - Chengqi Xu
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China.
| | - Yufeng Yao
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China.
| | - Qing K Wang
- Center for Human Genome Research, Key Laboratory of Molecular Biophysics of the Ministry of Education, and College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, P. R. China.
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9
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Role of Integrins in Modulating Smooth Muscle Cell Plasticity and Vascular Remodeling: From Expression to Therapeutic Implications. Cells 2022; 11:cells11040646. [PMID: 35203297 PMCID: PMC8870356 DOI: 10.3390/cells11040646] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 02/03/2022] [Accepted: 02/11/2022] [Indexed: 02/06/2023] Open
Abstract
Smooth muscle cells (SMCs), present in the media layer of blood vessels, are crucial in maintaining vascular homeostasis. Upon vascular injury, SMCs show a high degree of plasticity, undergo a change from a “contractile” to a “synthetic” phenotype, and play an essential role in the pathophysiology of diseases including atherosclerosis and restenosis. Integrins are cell surface receptors, which are involved in cell-to-cell binding and cell-to-extracellular-matrix interactions. By binding to extracellular matrix components, integrins trigger intracellular signaling and regulate several of the SMC function, including proliferation, migration, and phenotypic switching. Although pharmacological approaches, including antibodies and synthetic peptides, have been effectively utilized to target integrins to limit atherosclerosis and restenosis, none has been commercialized yet. A clear understanding of how integrins modulate SMC biology is essential to facilitate the development of integrin-based interventions to combat atherosclerosis and restenosis. Herein, we highlight the importance of integrins in modulating functional properties of SMCs and their implications for vascular pathology.
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10
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Abstract
Vascular smooth muscle cells (VSMC) are now considered important contributors to the pathophysiological and biophysical mechanisms underlying arterial stiffening in aging. Here, we review mechanisms whereby VSMC stiffening alters vascular function and contributes to the changes in vascular stiffening observed in aging and cardiovascular disease. Vascular stiffening in arterial aging was historically associated with changes in the extracellular matrix; however, new evidence suggests that endothelial and vascular smooth muscle cell stiffness also contribute to overall blood vessel stiffness. Furthermore, VSMC play an integral role in regulating matrix deposition and vessel wall contractility via interaction between the actomyosin contractile unit and adhesion structures that anchor the cell within the extracellular matrix. Aged-induce phenotypic modulation of VSMC from a contractile to a synthetic phenotype is associated with decreased cellular contractility and increased cell stiffness. Aged VSMC also display reduced mechanosensitivity and adaptation to mechanical signals from their microenvironment due to impaired intracellular signaling. Finally, evidence for decreased contractility in arteries from aged animals demonstrate that changes at the cellular level result in decreased functional properties at the tissue level.
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Role of mechanosignaling on pathology of varicose vein. Biophys Rev 2021; 13:139-145. [PMID: 33747248 DOI: 10.1007/s12551-021-00783-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/05/2021] [Indexed: 12/17/2022] Open
Abstract
Varicose veins are the most common vascular disease in humans. Veins have valves that help the blood return gradually to the heart without leaking blood. When these valves become weak, blood and fluid collect and pool by pressing against the walls of the veins, causing varicose veins. In the cardiovascular system, mechanical forces are important determinants of vascular homeostasis and pathological processes. Blood vessels are constantly exposed to a variety of hemodynamic forces, including shear stress and environmental strains caused by the blood flow. In varicose veins within the leg, venous blood pressure rises in the vein of the lower extremities due to prolonged standing, creating a peripheral tension in the vessel wall thereby causing mechanical stimulation of endothelial cells and vascular smooth muscle. Studies have shown that long-term increased exposure to vascular wall tension is associated with the overexpression of HIF-1α and HIF-2α and increased levels of MMP-2 and MMP-9, thereby reducing venous contraction and progressive venous dilatation, which is involved in the development of varicose veins. Following the expression of metalloproteinase, the expression of type 1 collagen increases, and the amount of type 3 collagen decreases. Therefore, collagen imbalance will cause the varicose veins to not stretch. Loss of structural proteins (type 3 collagen and elastin) in the vessel wall causes the loss of the biophysical properties of the varicose vein wall. This review article tries to elaborate on the effect of mechanical forces and sensors of these forces on the vascular wall in creating the mechanism of mechanosignaling, as well as the role of the onset of molecular signaling cascades in the pathology of varicose veins.
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Davaapil H, Shetty DK, Sinha S. Aortic "Disease-in-a-Dish": Mechanistic Insights and Drug Development Using iPSC-Based Disease Modeling. Front Cell Dev Biol 2020; 8:550504. [PMID: 33195187 PMCID: PMC7655792 DOI: 10.3389/fcell.2020.550504] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 10/08/2020] [Indexed: 12/24/2022] Open
Abstract
Thoracic aortic diseases, whether sporadic or due to a genetic disorder such as Marfan syndrome, lack effective medical therapies, with limited translation of treatments that are highly successful in mouse models into the clinic. Patient-derived induced pluripotent stem cells (iPSCs) offer the opportunity to establish new human models of aortic diseases. Here we review the power and potential of these systems to identify cellular and molecular mechanisms underlying disease and discuss recent advances, such as gene editing, and smooth muscle cell embryonic lineage. In particular, we discuss the practical aspects of vascular smooth muscle cell derivation and characterization, and provide our personal insights into the challenges and limitations of this approach. Future applications, such as genotype-phenotype association, drug screening, and precision medicine are discussed. We propose that iPSC-derived aortic disease models could guide future clinical trials via “clinical-trials-in-a-dish”, thus paving the way for new and improved therapies for patients.
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Affiliation(s)
- Hongorzul Davaapil
- Wellcome-MRC Cambridge Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Cambridge, United Kingdom
| | - Deeti K Shetty
- Wellcome-MRC Cambridge Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Cambridge, United Kingdom
| | - Sanjay Sinha
- Wellcome-MRC Cambridge Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Cambridge, United Kingdom
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Oxidative Stress: A Possible Trigger for Pelvic Organ Prolapse. J Immunol Res 2020; 2020:3791934. [PMID: 32953891 PMCID: PMC7481916 DOI: 10.1155/2020/3791934] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 08/06/2020] [Accepted: 08/21/2020] [Indexed: 01/23/2023] Open
Abstract
Pelvic organ prolapse is a frequent health problem in women, encountered worldwide, its physiopathology being still incompletely understood. The integrity of the pelvic-supportive structures is a key element that prevents the prolapse of the pelvic organs. Numerous researchers have underlined the role of connective tissue molecular changes in the pathogenesis of pelvic organ prolapse and have raised the attention upon oxidative stress as an important element involved in its appearance. The advancements made over the years in terms of molecular biology have allowed researchers to investigate how the constituent elements of the pelvic-supportive structures react in conditions of oxidative stress. The purpose of this paper is to underline the importance of oxidative stress in the pathogenesis of pelvic organ prolapse, as well as to highlight the main oxidative stress molecular changes that appear at the level of the pelvic-supportive structures. Sustained mechanical stress is proven to be a key factor in the appearance of pelvic organ prolapse, correlating with increased levels of free radicals production and mitochondrial-induced fibroblasts apoptosis, the rate of cellular apoptosis depending on the intensity of the mechanical stress, and the period of time the mechanical stress is applied. Oxidative stress hinders normal cellular signaling pathways, as well as different important cellular components like proteins, lipids, and cellular DNA, therefore significantly interfering with the process of collagen and elastin synthesis.
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TMT-Based Quantitative Proteomic Analysis Identification of Integrin Alpha 3 and Integrin Alpha 5 as Novel Biomarkers in Pathogenesis of Acute Aortic Dissection. BIOMED RESEARCH INTERNATIONAL 2020; 2020:1068402. [PMID: 32851057 PMCID: PMC7441460 DOI: 10.1155/2020/1068402] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 04/27/2020] [Accepted: 06/04/2020] [Indexed: 12/31/2022]
Abstract
Background Acute aortic dissection (AAD) is a devastating cardiovascular disease with a high rate of disability and mortality. This disease often rapidly progresses to fatal multiple organ hypoperfusion, and the incidence has been increasing in recent years. However, the molecular mechanisms have yet to be clarified. This study is aimed at identifying the differential abundance proteins (DAPs) of aortic arch tissues in patients with AAD by proteomics and select possible proteins involved in AAD pathogenesis. Methods The fresh aortic arch tissues obtained from 5 AAD patients and 1 healthy donor were analyzed by amine-reactive tandem mass tag (TMT) labelling and mass spectrometry; then, the pathological sections of another 10 healthy donors and 20 AAD patients were chosen to verify the proteomic results by immunohistochemistry. Results Of 809 proteins identified by proteomic analysis, 132 differential abundance proteins (DAPs) were screened, of which 100 proteins were significantly downregulated while 32 upregulated. Among 100 downregulated proteins, two proteins with known function, integrin alpha 3 (ITGA-3) and ITGA-5, were selected as target proteins involved in AAD pathogenesis. Two target DAPs were verified by immunohistochemisty, and the results showed that the integrated option density (IOD) of ITGA-3 and ITGA-5 in AAD patients was significantly lower than that in healthy donors, which were consistent with the proteomic results (P < 0.001). Conclusion ITGA-3 and ITGA-5 represent novel biomarkers for the pathogenesis of AAD and might be a therapeutic target in the future.
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Abstract
BACKGROUND Endothelial cells (ECs) sense the forces from blood flow through the glycocalyx, a carbohydrate rich luminal surface layer decorating most cells, and through forces transmitted through focal adhesions (FAs) on the abluminal side of the cell. OBJECTIVES This perspective paper explores a complementary hypothesis, that glycocalyx molecules on the abluminal side of the EC between the basement membrane and the EC membrane, occupying the space outside of FAs, work in concert with FAs to sense blood flow-induced shear stress applied to the luminal surface. RESULTS First, we summarize recent studies suggesting that the glycocalyx repels the plasma membrane away from the basement membrane, while integrin molecules attach to extracellular matrix (ECM) ligands. This coordinated attraction and repulsion results in the focal nature of integrin-mediated adhesion making the abluminal glycocalyx a participant in mechanotransduction. Further, the glycocalyx mechanically links the plasma membrane to the basement membrane providing a mechanism of force transduction when the cell deforms in the peri-FA space. To determine if the membrane might deform against a restoring force of an elastic abluminal glycocalyx in the peri-FA space we present some analysis from a multicomponent elastic finite element model of a sheared and focally adhered endothelial cell whose abluminal topography was assessed using quantitative total internal reflection fluorescence microscopy with an assumption that glycocalyx fills the space between the membrane and extracellular matrix. CONCLUSIONS While requiring experimental verification, this analysis supports the hypothesis that shear on the luminal surface can be transmitted to the abluminal surface and deform the cell in the vicinity of the focal adhesions, with the magnitude of deformation depending on the abluminal glycocalyx modulus.
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Affiliation(s)
- Peter J Butler
- Department of Biomedical Engineering and Intercollege Graduate Program of Bioengineering, The Pennsylvania State University, University Park, PA, USA
| | - Amit Bhatnagar
- Department of Biomedical Engineering and Intercollege Graduate Program of Bioengineering, The Pennsylvania State University, University Park, PA, USA
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Massett MP, Bywaters BC, Gibbs HC, Trzeciakowski JP, Padgham S, Chen J, Rivera G, Yeh AT, Milewicz DM, Trache A. Loss of smooth muscle α-actin effects on mechanosensing and cell-matrix adhesions. Exp Biol Med (Maywood) 2020; 245:374-384. [PMID: 32064918 PMCID: PMC7370591 DOI: 10.1177/1535370220903012] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Accepted: 01/08/2020] [Indexed: 12/20/2022] Open
Abstract
Mutations in ACTA2 , encoding smooth muscle α-actin, are a frequent cause of heritable thoracic aortic aneurysm and dissections. These mutations are associated with impaired vascular smooth muscle cell function, which leads to decreased ability of the cell to sense matrix-mediated mechanical stimuli. This study investigates how loss of smooth muscle α-actin affects cytoskeletal tension development and cell adhesion using smooth muscle cells explanted from aorta of mice lacking smooth muscle α-actin. We tested the hypothesis that reduced vascular smooth muscle contractility due to a loss of smooth muscle α-actin decreases cellular mechanosensing by dysregulating cell adhesion to the matrix. Assessment of functional mechanical properties of the aorta by stress relaxation measurements in thoracic aortic rings suggested two functional regimes for Acta2 −/− mice. Lower stress relaxation was recorded in aortic rings from Acta2 −/− mice at tensions below 10 mN compared with wild type, likely driven by cytoskeletal-dependent contractility. However, no differences were recorded between the two groups above the 10 mN threshold, since at higher tension the matrix-dependent contractility may be predominant. In addition, our results showed that at any given level of stretch, transmural pressure is lower in aortic rings from Acta2 −/− mice than wild type mice. In addition, a three-dimensional collagen matrix contractility assay showed that collagen pellets containing Acta2 −/− smooth muscle cells contracted less than the pellets containing the wild type cells. Moreover, second harmonic generation non-linear microscopy revealed that Acta2 −/− cells locally remodeled the collagen matrix fibers to a lesser extent than wild type cells. Quantification of protein fluorescence measurements in cells also showed that in absence of smooth muscle α-actin, there is a compensatory increase in smooth muscle γ-actin. Moreover, specific integrin recruitment at cell–matrix adhesions was reduced in Acta2 −/− cells. Thus, our findings suggest that Acta2 −/− cells are unable to generate external forces to remodel the matrix due to reduced contractility and interaction with the matrix.
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Affiliation(s)
- MP Massett
- Department of Health and Kinesiology, Texas A&M University, College Station, TX 77843, USA
| | - BC Bywaters
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA
| | - HC Gibbs
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
| | - JP Trzeciakowski
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA
| | - S Padgham
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA
| | - J Chen
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA
| | - G Rivera
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA
| | - AT Yeh
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
| | - DM Milewicz
- Department of Internal Medicine, McGovern Medical School, University of Texas Health Science Center, Houston, TX 77030, USA
| | - A Trache
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843, USA
- Department of Medical Physiology, Texas A&M University Health Science Center, Bryan, TX 77807, USA
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Björling K, Joseph PD, Egebjerg K, Salomonsson M, Hansen JL, Ludvigsen TP, Jensen LJ. Role of age, Rho-kinase 2 expression, and G protein-mediated signaling in the myogenic response in mouse small mesenteric arteries. Physiol Rep 2018; 6:e13863. [PMID: 30198176 PMCID: PMC6129776 DOI: 10.14814/phy2.13863] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2018] [Accepted: 08/21/2018] [Indexed: 12/16/2022] Open
Abstract
The myogenic response (MR) and myogenic tone (MT) in resistance vessels is crucial for maintaining peripheral vascular resistance and blood flow autoregulation. Development of MT involves G protein-coupled receptors, and may be affected by aging. AIMS (1) to estimate the mesenteric blood flow in myogenically active small mesenteric arteries; (2) to investigate the signaling from Gαq/11 and/or Gα12 activation to MT development; (3) to investigate the role of Rho-kinase 2 and aging on MT in mesenteric resistance arteries. METHODS we used pressure myography, quantitative real-time PCR, and immunolocalization to study small (<200 μm) mesenteric arteries (SMA) from young, mature adult, and middle aged mice. RESULTS Poiseuille flow calculations indicated autoregulation of blood flow at 60-120 mm Hg arterial pressure. Gαq/11 and Gα12 were abundantly expressed at the mRNA and protein levels in SMA. The Gαq/11 inhibitor YM-254890 suppressed MT development, and the Phosholipase C inhibitors U73122 and ET-18-OCH3 robustly inhibited it. We found an age-dependent increase in ROCK2 mRNA expression, and in basal MT. The specific ROCK2 inhibitor KD025 robustly inhibited MT in SMAs in all mice with an age-dependent variation in KD025 sensitivity. The inhibitory effect of KD025 was not prevented by the L-type Ca2+ channel activator BayK 8644. KD025 reversibly inhibited MT and endothelin-1 vasoconstriction in small pial arteries from Göttingen minipigs. CONCLUSIONS MT development in SMAs occurs through a Gαq/11 /PLC/Ca2+ -dependent pathway, and is maintained via ROCK2-mediated Ca2+ sensitization. Increased MT at mature adulthood can be explained by increased ROCK2 expression/activity.
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Affiliation(s)
- Karl Björling
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
| | - Philomeena D. Joseph
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
| | - Kristian Egebjerg
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
| | - Max Salomonsson
- Department of Biomedical SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenCopenhagen NDenmark
- Department of Internal MedicineTrelleborg HospitalTrelleborgSweden
| | | | | | - Lars J. Jensen
- Department of Veterinary and Animal SciencesFaculty of Health and Medical SciencesUniversity of CopenhagenFrederiksberg CCopenhagenDenmark
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Mechanisms of I/R-Induced Endothelium-Dependent Vasodilator Dysfunction. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2017; 81:331-364. [PMID: 29310801 DOI: 10.1016/bs.apha.2017.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Ischemia/reperfusion (I/R) induces leukocyte/endothelial cell adhesive interactions (LECA) in postcapillary venules and impaired endothelium-dependent, NO-mediated dilatory responses (EDD) in upstream arterioles. A large body of evidence has implicated reactive oxygen species, adherent leukocytes, and proteases in postischemic EDD dysfunction in conduit arteries. However, arterioles represent the major site for the regulation of vascular resistance but have received less attention with regard to the mechanisms underlying their reduced responsiveness to EDD stimuli in I/R. Even though leukocytes do not roll along, adhere to, or emigrate across arteriolar endothelium in postischemic intestine, recent work indicates that I/R-induced venular LECA is causally linked to EDD in arterioles. An emerging body of evidence suggests that I/R-induced EDD in arterioles occurs by a mechanism that is triggered by LECA in postcapillary venules and involves the formation of signals in the interstitium elicited by the proteolytic activity of emigrated leukocytes. This activity releases matricryptins from or exposes matricryptic sites in the extracellular matrix that interact with the integrin αvβ3 to induce mast cell chymase-dependent formation of angiotensin II (Ang II). Subsequent activation of NAD(P)H oxidase by Ang II leads to the formation of oxidants which inactivate NO and leads to eNOS uncoupling, resulting in arteriolar EDD dysfunction. This work establishes new links between LECA in postcapillary venules, signals generated in the interstitium by emigrated leukocytes, mast cell degranulation, and impaired EDD in upstream arterioles. These fundamentally important findings have enormous implications for our understanding of blood flow dysregulation in conditions characterized by I/R.
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Lockett AD, Wu Y, Gunst SJ. Elastase alters contractility and promotes an inflammatory synthetic phenotype in airway smooth muscle tissues. Am J Physiol Lung Cell Mol Physiol 2017; 314:L626-L634. [PMID: 29212803 DOI: 10.1152/ajplung.00334.2017] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Neutrophil elastase is secreted by inflammatory cells during airway inflammation and can elicit airway hyperreactivity in vivo. Elastase can degrade multiple components of the extracellular matrix. We hypothesized that elastase might disrupt the connections between airway smooth muscle (ASM) cells and the extracellular matrix and that this might have direct effects on ASM tissue responsiveness and inflammation. The effect of elastase treatment on ASM contractility was assessed in vitro in isolated strips of canine tracheal smooth muscle by stimulation of tissues with cumulatively increasing concentrations of acetylcholine (ACh) and measurement of contractile force. Elastase treatment potentiated contractile responses to ACh at low concentrations but suppressed the maximal contractile force generated by the tissues without affecting the phosphorylation of myosin regulatory light chain (RLC). Elastase also promoted the secretion of eotaxin and the activation of Akt in ASM tissues and decreased expression of smooth muscle myosin heavy chain, consistent with promotion of a synthetic inflammatory phenotype. As the degradation of matrix proteins can alter integrin engagement, we evaluated the effect of elastase on the assembly and activation of integrin-associated adhesion junction complexes in ASM tissues. Elastase led to talin cleavage, reduced talin binding to vinculin, and suppressed activation of the adhesome proteins paxillin, focal adhesion kinase, and vinculin, indicating that elastase causes the disassembly of adhesion junction complexes and the inactivation of adhesome signaling proteins. We conclude that elastase promotes an inflammatory phenotype and increased sensitivity to ACh in ASM tissues by disrupting signaling pathways mediated by integrin-associated adhesion complexes.
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Affiliation(s)
- Angelia D Lockett
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine , Indianapolis, Indiana
| | - Yidi Wu
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine , Indianapolis, Indiana
| | - Susan J Gunst
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine , Indianapolis, Indiana
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Hong K, Zhao G, Hong Z, Sun Z, Yang Y, Clifford PS, Davis MJ, Meininger GA, Hill MA. Mechanical activation of angiotensin II type 1 receptors causes actin remodelling and myogenic responsiveness in skeletal muscle arterioles. J Physiol 2016; 594:7027-7047. [PMID: 27531064 PMCID: PMC5134373 DOI: 10.1113/jp272834] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 08/09/2016] [Indexed: 12/15/2022] Open
Abstract
KEY POINTS Candesartan, an inverse agonist of the type 1 angiotensin II receptor (AT1 R), causes a concentration-dependent inhibition of pressure-dependent myogenic tone consistent with previous reports of mechanosensitivity of this G protein-coupled receptor. Mechanoactivation of the AT1 R occurs independently of local angiotensin II production and the type 2 angiotensin receptor. Mechanoactivation of the AT1 R stimulates actin polymerization by a protein kinase C-dependent mechanism, but independently of a change in intracellular Ca2+ . Using atomic force microscopy, changes in single vascular smooth muscle cell cortical actin are observed to remodel following mechanoactivation of the AT1 R. ABSTRACT The Gq/11 protein-coupled angiotensin II type 1 receptor (AT1 R) has been shown to be activated by mechanical stimuli. In the vascular system, evidence supports the AT1 R being a mechanosensor that contributes to arteriolar myogenic constriction. The aim of this study was to determine if AT1 R mechanoactivation affects myogenic constriction in skeletal muscle arterioles and to determine underlying cellular mechanisms. Using pressure myography to study rat isolated first-order cremaster muscle arterioles the AT1 R inhibitor candesartan (10-7 -10-5 m) showed partial but concentration-dependent inhibition of myogenic reactivity. Inhibition was demonstrated by a rightward shift in the pressure-diameter relationship over the intraluminal pressure range, 30-110 mmHg. Pressure-induced changes in global vascular smooth muscle intracellular Ca2+ (using Fura-2) were similar in the absence or presence of candesartan, indicating that AT1 R-mediated myogenic constriction relies on Ca2+ -independent downstream signalling. The diacylglycerol analogue 1-oleoyl-2-acetyl-sn-glycerol (OAG) reversed the inhibitory effect of candesartan, while this rescue effect was prevented by the protein kinase C (PKC) inhibitor GF 109203X. Both candesartan and PKC inhibition caused increased G-actin levels, as determined by Western blotting of vessel lysates, supporting involvement of cytoskeletal remodelling. At the single vascular smooth muscle cell level, atomic force microscopy showed that cell swelling (stretch) with hypotonic buffer also caused thickening of cortical actin fibres and this was blocked by candesartan. Collectively, the present studies support growing evidence for novel modes of activation of the AT1 R in arterioles and suggest that mechanically activated AT1 R generates diacylglycerol, which in turn activates PKC which induces the actin cytoskeleton reorganization that is required for pressure-induced vasoconstriction.
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Affiliation(s)
- Kwangseok Hong
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
- Robert M. Berne Cardiovascular Research Centre and Department of Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA22908USA
| | - Guiling Zhao
- College of Applied Health SciencesUniversity of Illinois at ChicagoChicagoIL60612USA
| | - Zhongkui Hong
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Biomedical EngineeringUniversity of South DakotaSioux FallsSD57107USA
| | - Zhe Sun
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
| | - Yan Yang
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
| | - Philip S. Clifford
- College of Applied Health SciencesUniversity of Illinois at ChicagoChicagoIL60612USA
| | - Michael J. Davis
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
| | - Gerald A. Meininger
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
| | - Michael A. Hill
- Dalton Cardiovascular Research CentreUniversity of MissouriColumbiaMO65211USA
- Department of Medical Pharmacology and PhysiologyUniversity of MissouriColumbiaMO65211USA
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Liu H, Gong X, Jing X, Ding X, Yao Y, Huang Y, Fan Y. Shear stress with appropriate time-step and amplification enhances endothelial cell retention on vascular grafts. J Tissue Eng Regen Med 2016; 11:2965-2978. [DOI: 10.1002/term.2196] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 02/09/2016] [Accepted: 03/14/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Haifeng Liu
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
| | - Xianghui Gong
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
| | - Xiaohui Jing
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
| | - Xili Ding
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
| | - Yuan Yao
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
| | - Yan Huang
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
| | - Yubo Fan
- Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering; Beihang University; Beijing People's Republic of China
- National Research Centre for Rehabilitation Technical Aids; Beijing People's Republic of China
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22
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Lu X, Kassab GS. Integrins mediate mechanical compression-induced endothelium-dependent vasodilation through endothelial nitric oxide pathway. ACTA ACUST UNITED AC 2016; 146:221-32. [PMID: 26324675 PMCID: PMC4555471 DOI: 10.1085/jgp.201411350] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Integrins mediate endothelial NO production and vasodilation in response to the compression of muscle arterioles. Cardiac and skeletal muscle contraction lead to compression of intramuscular arterioles, which, in turn, leads to their vasodilation (a process that may enhance blood flow during muscle activity). Although endothelium-derived nitric oxide (NO) has been implicated in compression-induced vasodilation, the mechanism whereby arterial compression elicits NO production is unclear. We cannulated isolated swine (n = 39) myocardial (n = 69) and skeletal muscle (n = 60) arteriole segments and exposed them to cyclic transmural pressure generated by either intraluminal or extraluminal pressure pulses to simulate compression in contracting muscle. We found that the vasodilation elicited by internal or external pressure pulses was equivalent; moreover, vasodilation in response to pressure depended on changes in arteriole diameter. Agonist-induced endothelium-dependent and -independent vasodilation was used to verify endothelial and vascular smooth muscle cell viability. Vasodilation in response to cyclic changes in transmural pressure was smaller than that elicited by pharmacological activation of the NO signaling pathway. It was attenuated by inhibition of NO synthase and by mechanical removal of the endothelium. Stemming from previous observations that endothelial integrin is implicated in vasodilation in response to shear stress, we found that function-blocking integrin α5β1 or αvβ3 antibodies attenuated cyclic compression–induced vasodilation and NOx (NO−2 and NO−3) production, as did an RGD peptide that competitively inhibits ligand binding to some integrins. We therefore conclude that integrin plays a role in cyclic compression–induced endothelial NO production and thereby in the vasodilation of small arteries during cyclic transmural pressure loading.
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Affiliation(s)
- Xiao Lu
- Department of Biomedical Engineering, Department of Cellular and Integrative Physiology, Department of Surgery, and Indiana Center for Vascular Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202
| | - Ghassan S Kassab
- Department of Biomedical Engineering, Department of Cellular and Integrative Physiology, Department of Surgery, and Indiana Center for Vascular Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202 Department of Biomedical Engineering, Department of Cellular and Integrative Physiology, Department of Surgery, and Indiana Center for Vascular Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202 Department of Biomedical Engineering, Department of Cellular and Integrative Physiology, Department of Surgery, and Indiana Center for Vascular Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202 Department of Biomedical Engineering, Department of Cellular and Integrative Physiology, Department of Surgery, and Indiana Center for Vascular Biology and Medicine, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202
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23
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Brozovich FV, Nicholson CJ, Degen CV, Gao YZ, Aggarwal M, Morgan KG. Mechanisms of Vascular Smooth Muscle Contraction and the Basis for Pharmacologic Treatment of Smooth Muscle Disorders. Pharmacol Rev 2016; 68:476-532. [PMID: 27037223 PMCID: PMC4819215 DOI: 10.1124/pr.115.010652] [Citation(s) in RCA: 298] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The smooth muscle cell directly drives the contraction of the vascular wall and hence regulates the size of the blood vessel lumen. We review here the current understanding of the molecular mechanisms by which agonists, therapeutics, and diseases regulate contractility of the vascular smooth muscle cell and we place this within the context of whole body function. We also discuss the implications for personalized medicine and highlight specific potential target molecules that may provide opportunities for the future development of new therapeutics to regulate vascular function.
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Affiliation(s)
- F V Brozovich
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - C J Nicholson
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - C V Degen
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - Yuan Z Gao
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - M Aggarwal
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
| | - K G Morgan
- Department of Health Sciences, Boston University, Boston, Massachusetts (C.J.N., Y.Z.G., M.A., K.G.M.); Department of Medicine, Mayo Clinic, Rochester, Minnesota (F.V.B.); and Paracelsus Medical University Salzburg, Salzburg, Austria (C.V.D.)
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Kufaishi H, Alarab M, Drutz H, Lye S, Shynlova O. Static Mechanical Loading Influences the Expression of Extracellular Matrix and Cell Adhesion Proteins in Vaginal Cells Derived From Premenopausal Women With Severe Pelvic Organ Prolapse. Reprod Sci 2016; 23:978-92. [PMID: 26823071 DOI: 10.1177/1933719115625844] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
INTRODUCTION Primary human vaginal cells derived from women with severe pelvic organ prolapse (POP-HVCs) demonstrate altered cellular characteristics as compared to cells derived from asymptomatic women (control-HVCs). Using computer-controllable Flexcell stretch unit, we examined whether POP-HVCs react differently to mechanical loading as compared to control-HVCs by the expression of extracellular matrix (ECM) components, cell-ECM adhesion proteins, and ECM degrading and maturating enzymes. METHODS Vaginal tissue biopsies from premenopausal patients with Pelvic Organ Prolapse Quantification System stage ≥3 (n = 8) and asymptomatic controls (n = 7) were collected during vaginal hysterectomy or repair. Human vaginal cells were isolated by enzymatic digestion, seeded on collagen (COLI)-coated plates, and stretched (24 hours, 25% elongation). Total RNA was extracted, and 84 genes were screened using Human ECM and Adhesion Molecules polymerase chain reaction array; selected genes were verified by quantitative reverse transcription-polymerase chain reaction. Stretch-conditioned media (SCM) were collected and analyzed by protein array, immunoblotting, and zymography. RESULTS In mechanically stretched control-HVCs, transcript levels of integrins (ITGA1, ITGA4, ITGAV, and ITGB1) and matrix metalloproteinases (MMPs) 2, 8, and 13 were downregulated (P < .05); in POP-HVCs, MMP1, MMP3, and MMP10, ADAMTS8 and 13, tissue inhibitor of metalloproteinases (TIMPs) 1 to 3, ITGA2, ITGA4, ITGA6, ITGB1, contactin (CNTN1), catenins (A1 and B1), and laminins (A3 and C1) were significantly upregulated, whereas COLs (1, 4, 5, 6, 11, and 12) and LOXL1 were downregulated. Human vaginal cells massively secrete MMPs and TIMPs proteins; MMP1, MMP8, MMP9 protein expression and MMP2 gelatinase activity were increased, whereas TIMP2 decreased in SCM from POP-HVCs compared to control-HVCs. CONCLUSIONS Primary human vaginal cells derived from women with severe pelvic organ prolapse and control-HVCs react differentially to in vitro mechanical stretch. Risk factors that induce stretch may alter ECM composition and cell-ECM interaction in pelvic floor tissue leading to the abatement of pelvic organ support and subsequent POP development.
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Affiliation(s)
- Hala Kufaishi
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - May Alarab
- Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Harold Drutz
- Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Stephen Lye
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Oksana Shynlova
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
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Sarelius IH, Titus PA, Maimon N, Okech W, Wilke-Mounts SJ, Brennan JR, Hocking DC. Extracellular matrix fibronectin initiates endothelium-dependent arteriolar dilatation via the heparin-binding, matricryptic RWRPK sequence of the first type III repeat of fibrillar fibronectin. J Physiol 2016; 594:687-97. [PMID: 26661689 DOI: 10.1113/jp271478] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 12/04/2015] [Indexed: 11/08/2022] Open
Abstract
KEY POINTS The local arteriolar dilatation produced by contraction of skeletal muscle is dependent upon multiple signalling mechanisms. In addition to the many metabolic signals that mediate this vasodilatation, we show here that the extracellular matrix protein fibronectin also contributes to the response. This vasodilatory signal requires the heparin-binding matricryptic RWRPK sequence in the first type III repeat of fibrillar fibronectin. The fibronectin-dependent component of the integrated muscle contraction-dependent arteriolar vasodilatation is coupled through an endothelial cell-dependent signalling pathway. Recent studies in contracting skeletal muscle have shown that functional vasodilatation in resistance arterioles has an endothelial cell (EC)-dependent component, and, separately have shown that the extracellular matrix protein fibronectin (FN) contributes to functional dilatation in these arterioles. Here we test the hypotheses that (i) the matricryptic heparin-binding region of the first type III repeat of fibrillar FN (FNIII1H) mediates vasodilatation, and (ii) this response is EC dependent. Engineered FN fragments with differing (defined) heparin- and integrin-binding capacities were applied directly to resistance arterioles in cremaster muscles of anaesthetized (pentobarbital sodium, 65 mg kg(-1)) mice. Both FNIII1H,8-10 and FNIII1H induced dilatations (12.2 ± 1.7 μm, n = 12 and 17.2 ± 2.4 μm, n = 14, respectively) whereas mutation of the active sequence (R(613) WRPK) of the heparin binding region significantly diminished the dilatation (3.2 ± 1.8 μm, n = 10). Contraction of skeletal muscle fibres via electrical field stimulation produced a vasodilatation (19.4 ± 1.2 μm, n = 12) that was significantly decreased (to 7.0 ± 2.7 μm, n = 7, P < 0.05) in the presence of FNIII1Peptide 6, which blocks extracellular matrix (ECM) FN and FNIII1H signalling. Furthermore, FNIII1H,8-10 and FNIII1H applied to EC-denuded arterioles failed to produce any dilatation indicating that endothelium was required for the response. Finally, FNIII1H significantly increased EC Ca(2+) (relative fluorescence 0.98 ± 0.02 in controls versus 1.12 ± 0.05, n = 17, P < 0.05). Thus, we conclude that ECM FN-dependent vasodilatation is mediated by the heparin-binding (RWRPK) sequence of FNIII1 in an EC-dependent manner. Importantly, blocking this signalling sequence decreased the dilatation to skeletal muscle contraction, indicating that there is a physiological role for this FN-dependent mechanism.
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Affiliation(s)
- Ingrid H Sarelius
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY, USA.,Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Patricia A Titus
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY, USA
| | - Nir Maimon
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY, USA
| | - William Okech
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Susan J Wilke-Mounts
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY, USA
| | - James R Brennan
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Denise C Hocking
- Department of Pharmacology and Physiology, University of Rochester, Rochester, NY, USA.,Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
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Kufaishi H, Alarab M, Drutz H, Lye S, Shynlova O. Comparative Characterization of Vaginal Cells Derived From Premenopausal Women With and Without Severe Pelvic Organ Prolapse. Reprod Sci 2016; 23:931-43. [PMID: 26763525 DOI: 10.1177/1933719115625840] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND This study tested a hypothesis that primary human vaginal cells derived from tissue of premenopausal women with severe pelvic organ prolapse (POP-HVCs) would display differential functional characteristics as compared to vaginal cells derived from asymptomatic women with normal pelvic floor support (control-HVCs). METHODS Vaginal tissue biopsies were collected from premenopausal patients with POP (n = 8) and asymptomatic controls (n = 7) during vaginal hysterectomy or repair. Primary vaginal cells were isolated by enzymatic digestion and characterized by immunocytochemistry. Cell attachment and proliferation on different matrices (collagen I, collagen II, collagen IV, fibronectin, laminin, tenascin, and vitronectin) were compared between POP-HVCs and control-HVCs. RNA was extracted, and the expression of 84 genes was screened using Human Extracellular Matrix and Adhesion Molecules RT(2) Profiler PCR array. The expression of selected genes was verified by quantitative reverse transcription-polymerase chain reaction. RESULTS (1) Control-HVCs attached to collagen IV more efficiently than POP-HVCs; (2) control-HVCs and POP-HVCs show a similar proliferation rate when plated on proNectin and collagen I; (3) when seeded on collagen I, resting POP-HVCs expressed significantly (P < .05) increased transcript levels of collagen VII, multiple matrix metalloproteinases (MMP3, MMP7, MMP10, MMP12, MMP13, and MMP14), integrins (ITGA1, ITGA4, ITGA6, ITGA8, ITGB1, ITGB2, and ITGB3), and cell adhesion molecules as compared to control-HVCs. Collagen XV and tissue inhibitors of MMPs (TIMP1 and TIMP2) as well as genes involved in the biogenesis and maturation of collagen and elastin fibers (LOX, LOXL1-LOXL3, BMP1, and ADAMTS2) were significantly downregulated in POP-HVCs versus control-HVCs (P < .05). CONCLUSIONS Resting primary POP-HVCs in vitro show altered cellular characteristics as compared to control-HVCs, which may influence their dynamic responses to external mechanical or hormonal stimuli.
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Affiliation(s)
- Hala Kufaishi
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - May Alarab
- Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Harold Drutz
- Division of Urogynecology and Reconstructive Pelvic Surgery, Department of Obstetrics and Gynecology, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Stephen Lye
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
| | - Oksana Shynlova
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada Department of Obstetrics and Gynecology, University of Toronto, Toronto, Ontario, Canada
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Abstract
Vascular smooth muscle (VSM; see Table 1 for a list of abbreviations) is a heterogeneous biomaterial comprised of cells and extracellular matrix. By surrounding tubes of endothelial cells, VSM forms a regulated network, the vasculature, through which oxygenated blood supplies specialized organs, permitting the development of large multicellular organisms. VSM cells, the engine of the vasculature, house a set of regulated nanomotors that permit rapid stress-development, sustained stress-maintenance and vessel constriction. Viscoelastic materials within, surrounding and attached to VSM cells, comprised largely of polymeric proteins with complex mechanical characteristics, assist the engine with countering loads imposed by the heart pump, and with control of relengthening after constriction. The complexity of this smart material can be reduced by classical mechanical studies combined with circuit modeling using spring and dashpot elements. Evaluation of the mechanical characteristics of VSM requires a more complete understanding of the mechanics and regulation of its biochemical parts, and ultimately, an understanding of how these parts work together to form the machinery of the vascular tree. Current molecular studies provide detailed mechanical data about single polymeric molecules, revealing viscoelasticity and plasticity at the protein domain level, the unique biological slip-catch bond, and a regulated two-step actomyosin power stroke. At the tissue level, new insight into acutely dynamic stress-strain behavior reveals smooth muscle to exhibit adaptive plasticity. At its core, physiology aims to describe the complex interactions of molecular systems, clarifying structure-function relationships and regulation of biological machines. The intent of this review is to provide a comprehensive presentation of one biomachine, VSM.
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Affiliation(s)
- Paul H Ratz
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, Virginia, USA
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Colinas O, Moreno-Domínguez A, Zhu HL, Walsh EJ, Pérez-García MT, Walsh MP, Cole WC. α5-Integrin-mediated cellular signaling contributes to the myogenic response of cerebral resistance arteries. Biochem Pharmacol 2015; 97:281-91. [PMID: 26278977 DOI: 10.1016/j.bcp.2015.08.088] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/10/2015] [Indexed: 12/24/2022]
Abstract
The myogenic response of resistance arterioles and small arteries involving constriction in response to intraluminal pressure elevation and dilation on pressure reduction is fundamental to local blood flow regulation in the microcirculation. Integrins have garnered considerable attention in the context of initiating the myogenic response, but evidence indicative of mechanotransduction by integrin adhesions, for example established changes in tyrosine phosphorylation of key adhesion proteins, has not been obtained to substantiate this interpretation. Here, we evaluated the role of integrin adhesions and associated cellular signaling in the rat cerebral arterial myogenic response using function-blocking antibodies against α5β1-integrins, pharmacological inhibitors of focal adhesion kinase (FAK) and Src family kinase (SFK), an ultra-high-sensitivity western blotting technique, site-specific phosphoprotein antibodies to quantify adhesion and contractile filament protein phosphorylation, and differential centrifugation to determine G-actin levels in rat cerebral arteries at varied intraluminal pressures. Pressure-dependent increases in the levels of phosphorylation of FAK (FAK-Y397, Y576/Y577), SFK (SFK-Y416; Y527 phosphorylation was reduced), vinculin-Y1065, paxillin-Y118 and phosphoinositide-specific phospholipase C-γ1 (PLCγ1)-Y783 were detected. Treatment with α5-integrin function-blocking antibodies, FAK inhibitor FI-14 or SFK inhibitor SU6656 suppressed the changes in adhesion protein phosphorylation, and prevented pressure-dependent phosphorylation of the myosin targeting subunit of myosin light chain phosphatase (MYPT1) at T855 and 20kDa myosin regulatory light chains (LC20) at S19, as well as actin polymerization that are necessary for myogenic constriction. We conclude that mechanotransduction by integrin adhesions and subsequent cellular signaling play a fundamental role in the cerebral arterial myogenic response.
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Affiliation(s)
- Olaia Colinas
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - Alejandro Moreno-Domínguez
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - Hai-Lei Zhu
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - Emma J Walsh
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - M Teresa Pérez-García
- Department of Physiology, Instituto de Biología y Genética Molecular, University of Valladolid, Valladolid, Spain.
| | - Michael P Walsh
- Smooth Muscle Research Group, Department of Biochemistry and Molecular Biology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
| | - William C Cole
- Smooth Muscle Research Group, Department of Physiology and Pharmacology, Hotchkiss Brain Institute and Libin Cardiovascular Institute, University of Calgary, Alberta, Canada.
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Castorena-Gonzalez JA, Staiculescu MC, Foote C, Martinez-Lemus LA. Mechanisms of the inward remodeling process in resistance vessels: is the actin cytoskeleton involved? Microcirculation 2015; 21:219-29. [PMID: 24635509 DOI: 10.1111/micc.12105] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Accepted: 11/04/2013] [Indexed: 12/22/2022]
Abstract
The resistance arteries and arterioles are the vascular components of the circulatory system where the greatest drop in blood pressure takes place. Consequently, these vessels play a preponderant role in the regulation of blood flow and the modulation of blood pressure. For this reason, the inward remodeling process of the resistance vasculature, as it occurs in hypertension, has profound consequences on the incidence of life-threatening cardiovascular events. In this manuscript, we review some of the most prominent characteristics of inwardly remodeled resistance arteries including their changes in vascular passive diameter, wall thickness, and elastic properties. Then, we explore the known contribution of the different components of the vascular wall to the characteristics of inwardly remodeled vessels, and pay particular attention to the role the vascular smooth muscle actin cytoskeleton may play on the initial stages of the remodeling process. We end by proposing potential ways by which many of the factors and mechanisms known to participate in the inward remodeling process may be associated with cytoskeletal modifications and participate in reducing the passive diameter of resistance vessels.
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Affiliation(s)
- Jorge A Castorena-Gonzalez
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, USA; Department of Biological Engineering, University of Missouri, Columbia, Missouri, USA
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Eddinger TJ. Smooth muscle-protein translocation and tissue function. Anat Rec (Hoboken) 2015; 297:1734-46. [PMID: 25125185 DOI: 10.1002/ar.22970] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Revised: 03/18/2014] [Accepted: 03/18/2014] [Indexed: 01/25/2023]
Abstract
Smooth muscle (SM) tissue is a complex organization of multiple cell types and is regulated by numerous signaling molecules (neurotransmitters, hormones, cytokines, etc.). SM contractile function can be regulated via expression and distribution of the contractile and cytoskeletal proteins, and activation of any of the second messenger pathways that regulate them. Spatial-temporal changes in the contractile, cytoskeletal or regulatory components of SM cells (SMCs) have been proposed to alter SM contractile activity. Ca(2+) sensitization/desensitization can occur as a result of changes at any of these levels, and specific pathways have been identified at all of these levels. Understanding when and how proteins can translocate within the cytoplasm, or to-and-from the plasmalemma and the cytoplasm to alter contractile activity is critical. Numerous studies have reported translocation of proteins associated with the adherens junction and G protein-coupled receptor activation pathways in isolated SMC systems. Specific examples of translocation of vinculin to and from the adherens junction and protein kinase C (PKC) and 17 kDa PKC-potentiated inhibitor of myosin light chain phosphatase (CPI-17) to and from the plasmalemma in isolated SMC systems but not in intact SM tissues are discussed. Using both isolated SMC systems and SM tissues in parallel to pursue these studies will advance our understanding of both the role and mechanism of these pathways as well as their possible significance for Ca(2+) sensitization in intact SM tissues and organ systems.
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Affiliation(s)
- Thomas J Eddinger
- Department of Biological Sciences, Marquette University, Milwaukee, Wisconsin
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Bloksgaard M, Leurgans TM, Nissen I, Jensen PS, Hansen ML, Brewer JR, Bagatolli LA, Marcussen N, Irmukhamedov A, Rasmussen LM, De Mey JG. Elastin Organization in Pig and Cardiovascular Disease Patients' Pericardial Resistance Arteries. J Vasc Res 2015; 52:1-11. [DOI: 10.1159/000376548] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 01/26/2015] [Indexed: 11/19/2022] Open
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Staiculescu MC, Ramirez-Perez FI, Castorena-Gonzalez JA, Hong Z, Sun Z, Meininger GA, Martinez-Lemus LA. Lysophosphatidic acid induces integrin activation in vascular smooth muscle and alters arteriolar myogenic vasoconstriction. Front Physiol 2014; 5:413. [PMID: 25400583 PMCID: PMC4215695 DOI: 10.3389/fphys.2014.00413] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 10/06/2014] [Indexed: 01/16/2023] Open
Abstract
In vascular smooth muscle cells (VSMC) increased integrin adhesion to extracellular matrix (ECM) proteins, as well as the production of reactive oxygen species (ROS) are strongly stimulated by lysophosphatidic acid (LPA). We hypothesized that LPA-induced generation of ROS increases integrin adhesion to the ECM. Using atomic force microscopy (AFM) we determined the effects of LPA on integrin adhesion to fibronectin (FN) in VSMC isolated from rat (Sprague-Dawley) skeletal muscle arterioles. In VSMC, exposure to LPA (2 μM) doubled integrin-FN adhesion compared to control cells (P < 0.05). LPA-induced integrin-FN adhesion was reduced by pre-incubation with antibodies against β1 and β3 integrins (50 μg/ml) by 66% (P < 0.05). Inhibition of LPA signaling via blockade of the LPA G-protein coupled receptors LPAR1 and LPAR3 with 10 μM Ki16425 reduced the LPA-enhanced adhesion of VSCM to FN by 40% (P < 0.05). Suppression of ROS with tempol (250 μM) or apocynin (300 μM) also reduced the LPA-induced FN adhesion by 47% (P < 0.05) and 59% (P < 0.05), respectively. Using confocal microscopy, we observed that blockade of LPA signaling, with Ki16425, reduced ROS by 45% (P < 0.05), to levels similar to control VSMC unexposed to LPA. In intact isolated arterioles, LPA (2 μM) exposure augmented the myogenic constriction response to step increases in intraluminal pressure (between 40 and 100 mm Hg) by 71% (P < 0.05). The blockade of LPA signaling, with Ki16425, decreased the LPA-enhanced myogenic constriction by 58% (P < 0.05). Similarly, blockade of LPA-induced ROS release with tempol or gp91 ds-tat decreased the LPA-enhanced myogenic constriction by 56% (P < 0.05) and 55% (P < 0.05), respectively. These results indicate that, in VSMC, LPA-induced integrin activation involves the G-protein coupled receptors LPAR1 and LPAR3, and the production of ROS, and that LPA may play an important role in the control of myogenic behavior in resistance vessels through ROS modulation of integrin activity.
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Affiliation(s)
| | - Francisco I Ramirez-Perez
- Dalton Cardiovascular Research Center, University of Missouri Columbia, MO, USA ; Department of Bioengineering, University of Missouri Columbia, MO, USA
| | - Jorge A Castorena-Gonzalez
- Dalton Cardiovascular Research Center, University of Missouri Columbia, MO, USA ; Department of Bioengineering, University of Missouri Columbia, MO, USA
| | - Zhongkui Hong
- Dalton Cardiovascular Research Center, University of Missouri Columbia, MO, USA
| | - Zhe Sun
- Dalton Cardiovascular Research Center, University of Missouri Columbia, MO, USA
| | - Gerald A Meininger
- Dalton Cardiovascular Research Center, University of Missouri Columbia, MO, USA ; Department of Bioengineering, University of Missouri Columbia, MO, USA ; Department of Medical Pharmacology and Physiology, University of Missouri Columbia, MO, USA
| | - Luis A Martinez-Lemus
- Dalton Cardiovascular Research Center, University of Missouri Columbia, MO, USA ; Department of Bioengineering, University of Missouri Columbia, MO, USA ; Department of Medical Pharmacology and Physiology, University of Missouri Columbia, MO, USA
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Adeoye OO, Bouthors V, Hubbell MC, Williams JM, Pearce WJ. VEGF receptors mediate hypoxic remodeling of adult ovine carotid arteries. J Appl Physiol (1985) 2014; 117:777-87. [PMID: 25038104 DOI: 10.1152/japplphysiol.00012.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recent studies suggest that VEGF contributes to hypoxic remodeling of arterial smooth muscle, although hypoxia produces only transient increases in VEGF that return to normoxic levels despite sustained changes in arterial structure and function. To explore how VEGF might contribute to long-term hypoxic vascular remodeling, this study explores the hypothesis that chronic hypoxia produces sustained increases in smooth muscle VEGF receptor density that mediate long-term vascular effects of hypoxia. Carotid arteries from adult sheep maintained at sea level or altitude (3,820 m) for 110 days were harvested and denuded of endothelium. VEGF levels were similar in chronically hypoxic and normoxic arteries, as determined by immunoblotting. In contrast, VEGF receptor levels were significantly increased by 107% (VEGF-R1) and 156% (VEGF-R2) in hypoxic compared with normoxic arteries. In arteries that were organ cultured 24 h with 3 nM VEGF, VEGF replicated effects of hypoxia on abundances of smooth muscle α actin (SMαA), myosin light chain kinase (MLCK), and MLC20 and the effects of hypoxia on colocalization of MLC20 with SMαA, as measured via confocal microscopy. VEGF did not replicate the effects of chronic hypoxia on colocalization of MLCK with SMαA or MLCK with MLC20, suggesting that VEGF's role in hypoxic remodeling is highly protein specific, particularly for contractile protein organization. VEGF effects in organ culture were inhibited by VEGF receptor blockers vatalinib (240 nM) and dasatinib (6.3 nM). These findings support the hypothesis that long-term upregulation of VEGF receptors help mediate sustained effects of hypoxia on the abundance and colocalization of contractile proteins in arterial smooth muscle.
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Affiliation(s)
- Olayemi O Adeoye
- Divisions of Physiology, Pharmacology, and Biochemistry, Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
| | - Vincent Bouthors
- Divisions of Physiology, Pharmacology, and Biochemistry, Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
| | - Margaret C Hubbell
- Divisions of Physiology, Pharmacology, and Biochemistry, Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
| | - James M Williams
- Divisions of Physiology, Pharmacology, and Biochemistry, Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
| | - William J Pearce
- Divisions of Physiology, Pharmacology, and Biochemistry, Center for Perinatal Biology, Loma Linda University School of Medicine, Loma Linda, California
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Sreenivasappa H, Chaki SP, Lim SM, Trzeciakowski JP, Davidson MW, Rivera GM, Trache A. Selective regulation of cytoskeletal tension and cell–matrix adhesion by RhoA and Src. Integr Biol (Camb) 2014; 6:743-54. [DOI: 10.1039/c4ib00019f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Saphirstein RJ, Morgan KG. The contribution of vascular smooth muscle to aortic stiffness across length scales. Microcirculation 2014; 21:201-7. [PMID: 24635219 PMCID: PMC8588963 DOI: 10.1111/micc.12101] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 10/17/2013] [Indexed: 01/09/2023]
Abstract
The operation of the cardiovascular system in health and disease is inherently mechanical. Clinically, aortic stiffness has proven to be of critical importance as an early biomarker for subsequent cardiovascular disease; however, the mechanisms involved in aortic stiffening are still unclear. The etiology of aortic stiffening with age has been thought to primarily involve changes in extracellular matrix protein composition and quantity, but recent studies suggest a significant involvement of the differentiated contractile vascular smooth muscle cells in the vessel wall. Here, we provide an overview of vascular physiology and biomechanics at different spatial scales. The processes involved in aortic stiffening are examined with particular attention given to recent discoveries regarding the role of vascular smooth muscle.
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Welschoff J, Matthey M, Wenzel D. RGD peptides induce relaxation of pulmonary arteries and airways
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β3‐integrins. FASEB J 2014; 28:2281-92. [DOI: 10.1096/fj.13-246348] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Turlo KA, Scapa J, Bagher P, Jones AW, Feil R, Korthuis RJ, Segal SS, Iruela-Arispe ML. β1-integrin is essential for vasoregulation and smooth muscle survival in vivo. Arterioscler Thromb Vasc Biol 2013; 33:2325-35. [PMID: 23887637 DOI: 10.1161/atvbaha.112.300648] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Integrins contribute to vascular morphogenesis through regulation of adhesion and assembly of the extracellular matrix. However, the role of β1-integrin in the mature vascular wall is less clear. APPROACH AND RESULTS We sought to determine the function of β1-integrin in mature smooth muscle cells in vivo using a loss of function approach by crossing a tamoxifen-inducible sm22αCre line to a floxed β1-integrin transgenic line. Adult mice lacking smooth muscle β1-integrin survived only 10 weeks post induction. The deletion of β1-integrin resulted in profound loss of vasomotor control. Histological analysis revealed progressive fibrosis in arteries with associated apoptosis of smooth muscle cells, which was not rescued by adventitial stem cells. Smooth muscle cell apoptosis was detected in arteries with dead cells replaced primarily by collagen. Despite the catastrophic effects on vascular smooth muscle, the deleted visceral smooth muscle remained viable with the exception of a short portion of the colon, indicating that vascular but not visceral smooth muscle is particularly sensitive to changes in β1-integrin. CONCLUSIONS This study reveals an essential function of β1-integrin in the maintenance of vasomotor control and highlights a critical role for β1-integrin in vascular, but not visceral, smooth muscle survival.
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Affiliation(s)
- Kirsten A Turlo
- From the Department of Molecular, Cellular, and Developmental Biology (K.A.T., M.L.I.-A.) and Molecular Biology Institute (J.S.), University of California, Los Angeles, CA; Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO (P.B., A.W.J., R.J.K., S.S.S.); Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany (R.F.); and Dalton Cardiovascular Research Center, Columbia, MO (A.W.J., R.J.K., S.S.S.)
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Saphirstein RJ, Gao YZ, Jensen MH, Gallant CM, Vetterkind S, Moore JR, Morgan KG. The focal adhesion: a regulated component of aortic stiffness. PLoS One 2013; 8:e62461. [PMID: 23626821 PMCID: PMC3633884 DOI: 10.1371/journal.pone.0062461] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 03/21/2013] [Indexed: 01/16/2023] Open
Abstract
Increased aortic stiffness is an acknowledged predictor and cause of cardiovascular disease. The sources and mechanisms of vascular stiffness are not well understood, although the extracellular matrix (ECM) has been assumed to be a major component. We tested here the hypothesis that the focal adhesions (FAs) connecting the cortical cytoskeleton of vascular smooth muscle cells (VSMCs) to the matrix in the aortic wall are a component of aortic stiffness and that this component is dynamically regulated. First, we examined a model system in which magnetic tweezers could be used to monitor cellular cortical stiffness, serum-starved A7r5 aortic smooth muscle cells. Lysophosphatidic acid (LPA), an activator of myosin that increases cell contractility, increased cortical stiffness. A small molecule inhibitor of Src-dependent FA recycling, PP2, was found to significantly inhibit LPA-induced increases in cortical stiffness, as well as tension-induced increases in FA size. To directly test the applicability of these results to force and stiffness development at the level of vascular tissue, we monitored mouse aorta ring stiffness with small sinusoidal length oscillations during agonist-induced contraction. The alpha-agonist phenylephrine, which also increases myosin activation and contractility, increased tissue stress and stiffness in a PP2- and FAK inhibitor 14-attenuated manner. Subsequent phosphotyrosine screening and follow-up with phosphosite-specific antibodies confirmed that the effects of PP2 and FAK inhibitor 14 in vascular tissue involve FA proteins, including FAK, CAS, and paxillin. Thus, in the present study we identify, for the first time, the FA of the VSMC, in particular the FAK-Src signaling complex, as a significant subcellular regulator of aortic stiffness and stress.
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Affiliation(s)
- Robert J. Saphirstein
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
- Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Yuan Z. Gao
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts, United States of America
- Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Mikkel H. Jensen
- Department of Physics, Boston University, Boston, Massachusetts, United States of America
- Department of Physiology and Biophysics, Boston University Medical School, Boston, Massachusetts, United States of America
| | - Cynthia M. Gallant
- Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Susanne Vetterkind
- Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
| | - Jeffrey R. Moore
- Department of Physiology and Biophysics, Boston University Medical School, Boston, Massachusetts, United States of America
| | - Kathleen G. Morgan
- Department of Health Sciences, Boston University, Boston, Massachusetts, United States of America
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Balasubramanian L, Lo CM, Sham JSK, Yip KP. Remanent cell traction force in renal vascular smooth muscle cells induced by integrin-mediated mechanotransduction. Am J Physiol Cell Physiol 2013; 304:C382-91. [PMID: 23325413 DOI: 10.1152/ajpcell.00234.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
It was previously demonstrated in isolated renal vascular smooth muscle cells (VSMCs) that integrin-mediated mechanotransduction triggers intracellular Ca(2+) mobilization, which is the hallmark of myogenic response in VSMCs. To test directly whether integrin-mediated mechanotransduction results in the myogenic response-like behavior in renal VSMCs, cell traction force microscopy was used to monitor cell traction force when the cells were pulled with fibronectin-coated or low density lipoprotein (LDL)-coated paramagnetic beads. LDL-coated beads were used as a control for nonintegrin-mediated mechanotransduction. Pulling with LDL-coated beads increased the cell traction force by 61 ± 12% (9 cells), which returned to the prepull level after the pulling process was terminated. Pulling with noncoated beads had a minimal increase in the cell traction force (12 ± 9%, 8 cells). Pulling with fibronectin-coated beads increased the cell traction force by 56 ± 20% (7 cells). However, the cell traction force was still elevated by 23 ± 14% after the pulling process was terminated. This behavior is analogous to the changes of vascular resistance in pressure-induced myogenic response, in which vascular resistance remains elevated after myogenic constriction. Fibronectin is a native ligand for α(5)β(1)-integrins in VSMCs. Similar remanent cell traction force was found when cells were pulled with beads coated with β(1)-integrin antibody (Ha2/5). Activation of β(1)-integrin with soluble antibody also triggered variations of cell traction force and Ca(2+) mobilization, which were abolished by the Src inhibitor. In conclusion, mechanical force transduced by α(5)β(1)-integrins triggered a myogenic response-like behavior in isolated renal VSMCs.
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Affiliation(s)
- Lavanya Balasubramanian
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
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Konttinen YT, Kaivosoja E, Stegaev V, Wagner HD, Levón J, Tiainen VM, Mackiewicz Z. Extracellular Matrix and Tissue Regeneration. Regen Med 2013. [DOI: 10.1007/978-94-007-5690-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Abstract
The myogenic response has a critical role in regulation of blood flow to the brain. Increased intraluminal pressure elicits vasoconstriction, whereas decreased intraluminal pressure induces vasodilatation, thereby maintaining flow constant over the normal physiologic blood pressure range. Improved understanding of the molecular mechanisms underlying the myogenic response is crucial to identify deficiencies with pathologic consequences, such as cerebral vasospasm, hypertension, and stroke, and to identify potential therapeutic targets. Three mechanisms have been suggested to be involved in the myogenic response: (1) membrane depolarization, which induces Ca(2+) entry, activation of myosin light chain kinase, phosphorylation of the myosin regulatory light chains (LC(20)), increased actomyosin MgATPase activity, cross-bridge cycling, and vasoconstriction; (2) activation of the RhoA/Rho-associated kinase (ROCK) pathway, leading to inhibition of myosin light chain phosphatase by phosphorylation of MYPT1, the myosin targeting regulatory subunit of the phosphatase, and increased LC(20) phosphorylation; and (3) activation of the ROCK and protein kinase C pathways, leading to actin polymerization and the formation of enhanced connections between the actin cytoskeleton, plasma membrane, and extracellular matrix to augment force transmission. This review describes these three mechanisms, emphasizing recent developments regarding the importance of dynamic actin polymerization in the myogenic response of the cerebral vasculature.
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Hong Z, Sun Z, Li Z, Mesquitta WT, Trzeciakowski JP, Meininger GA. Coordination of fibronectin adhesion with contraction and relaxation in microvascular smooth muscle. Cardiovasc Res 2012; 96:73-80. [PMID: 22802110 DOI: 10.1093/cvr/cvs239] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
AIMS The regulation of vascular diameter by vasoconstrictors and vasodilators requires that vascular smooth muscle cells (VSMCs) be physically coupled to extracellular matrix (ECM) and neighbouring cells in order for a vessel to mechanically function and transfer force. The hypothesis was tested that integrin-mediated adhesion to the ECM is dynamically up-regulated in VSMCs during contractile activation in response to a vasoconstrictor and likewise down-regulated during relaxation in response to a vasodilator. METHODS AND RESULTS VSMCs were isolated from the Sprague-Dawley rat cremaster muscles. Atomic force microscopy (AFM) with fibronectin (FN)-functionalized probes was employed to investigate the biomechanical responses and adhesion of VSMCs. Responses to angiotensin II (Ang II; 10(-6) M) and adenosine (Ado; 10(-4) M) were recorded by measurements of cell cortical elasticity and cell adhesion. The results showed that Ang II caused an immediate increase in adhesion (+27%) between the probe and cell. Cell stiffness increased (+70%) in parallel with the adhesion change. Ado decreased adhesion (-15%) to FN and reduced (-30%) stiffness. CONCLUSION Changes in the receptor-mediated activation of the contractile apparatus cause parallel alterations in cell adhesion and cell cortical elasticity. These studies support the hypothesis that the regulation of cell adhesion is coordinated with contraction and demonstrate the dynamic nature of cell adhesion to the ECM. It is proposed that coordination of adhesion and VSMC contraction is an important mechanism that allows for an efficient transfer of force between the contractile apparatus of the cell and the extracellular environment.
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Affiliation(s)
- Zhongkui Hong
- Dalton Cardiovascular Research Center, University of Missouri, 134 Research Park Dr., Columbia, MO 65211, USA
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Contrasting effects of aliskiren versus losartan on hypertensive vascular remodeling. Int J Cardiol 2012; 167:1199-205. [PMID: 22483258 DOI: 10.1016/j.ijcard.2012.03.137] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2012] [Accepted: 03/14/2012] [Indexed: 11/21/2022]
Abstract
BACKGROUND Hyperactivation of the renin-angiotensin system contributes to hypertension-induced upregulation of vascular matrix metalloproteinases (MMPs) and remodeling, especially in the two kidney, one clip (2K1C) hypertension model. We hypothesized that the AT1R antagonist losartan or the renin inhibitor aliskiren, given at doses allowing similar antihypertensive effects, could prevent in vivo vascular MMPs upregulation and remodeling, and collagen/elastin deposition found in 2K1C hypertension by preventing the activation of extracellular signal-regulated kinase 1/2 (ERK 1/2) and transforming growth factor-β1 (TGF-β1). We also hypothesized that aliskiren could enhance the effects of losartan. METHODS 2K1C rats were treated with aliskiren (50mg.kg(-1).day(-1)), or losartan (10mg.kg(-1).day(-1)), or both by gavage during 4 weeks. RESULTS Aliskiren, losartan, or both drugs exerted similar antihypertensive effects when compared with 2K-1C rats treated with water. Aliskiren reduced plasma renin activity in both sham and 2K-1C rats. Losartan alone or combined with aliskiren, but not aliskiren alone, abolished 2K1C-induced aortic hypertrophy and hyperplasia, and prevented the increases in aortic collagen/elastin content, MMP-2 levels, gelatinolytic activity, and expression of phospho-ERK 1/2 and TGF-β1. No significant differences were found in the aortic expression of the (pro)renin receptor. CONCLUSIONS These findings show that although losartan and aliskiren exerted similar antihypertensive effects, only losartan prevented the activation of vascular profibrotic mechanisms and MMP upregulation associated with vascular remodeling in 2K1C hypertension. Our findings also suggest that aliskiren does not enhance the protective effects exerted by losartan.
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Varicose veins: role of mechanotransduction of venous hypertension. Int J Vasc Med 2012; 2012:538627. [PMID: 22489273 PMCID: PMC3303599 DOI: 10.1155/2012/538627] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 11/13/2011] [Indexed: 11/17/2022] Open
Abstract
Varicose veins affect approximately one-third of the adult population and result in significant psychological, physical, and financial burden. Nevertheless, the molecular pathogenesis of varicose vein formation remains unidentified. Venous hypertension exerted on veins of the lower extremity is considered the principal factor in varicose vein formation. The role of mechanotransduction of the high venous pressure in the pathogenesis of varicose vein formation has not been adequately investigated despite a good progress in understanding the mechanomolecular mechanisms involved in transduction of high blood pressure in the arterial wall. Understanding the nature of the mechanical forces, the mechanosensors and mechanotransducers in the vein wall, and the downstream signaling pathways will provide new molecular targets for the prevention and treatment of varicose veins. This paper summarized the current understanding of mechano-molecular pathways involved in transduction of hemodynamic forces induced by blood pressure and tries to relate this information to setting of venous hypertension in varicose veins.
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Turlo KA, Noel ODV, Vora R, LaRussa M, Fassler R, Hall-Glenn F, Iruela-Arispe ML. An essential requirement for β1 integrin in the assembly of extracellular matrix proteins within the vascular wall. Dev Biol 2012; 365:23-35. [PMID: 22331032 DOI: 10.1016/j.ydbio.2012.01.027] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Revised: 12/30/2011] [Accepted: 01/30/2012] [Indexed: 01/22/2023]
Abstract
β1 integrin has been shown to contribute to vascular smooth muscle cell differentiation, adhesion and mechanosensation in vitro. Here we showed that deletion of β1 integrin at the onset of smooth muscle differentiation resulted in interrupted aortic arch, aneurysms and failure to assemble extracellular matrix proteins. These defects result in lethality prior to birth. Our data indicates that β1 integrin is not required for the acquisition, but it is essential for the maintenance of the smooth muscle cell phenotype, as levels of critical smooth muscle proteins are gradually reduced in mutant mice. Furthermore, while deposition of extracellular matrix was not affected, its structure was disrupted. Interestingly, defects in extracellular matrix and vascular wall assembly, were restricted to the aortic arch and its branches, compromising the brachiocephalic and carotid arteries and to the exclusion of the descending aorta. Additional analysis of β1 integrin in the pharyngeal arch smooth muscle progenitors was performed using wnt1Cre. Neural crest cells deleted for β1 integrin were able to migrate to the pharyngeal arches and associate with endothelial lined arteries; but exhibited vascular remodeling defects and early lethality. This work demonstrates that β1 integrin is dispensable for migration and initiation of the smooth muscle differentiation program, however, it is essential for remodeling of the pharyngeal arch arteries and for the assembly of the vessel wall of their derivatives. It further establishes a critical role of β1 integrin in the protection against aneurysms that is particularly confined to the ascending aorta and its branches.
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Affiliation(s)
- Kirsten A Turlo
- Department of Molecular, Cellular, and Developmental Biology, University of California, Los Angeles, CA 90095, USA
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Wu X, Reddy DS. Integrins as receptor targets for neurological disorders. Pharmacol Ther 2011; 134:68-81. [PMID: 22233753 DOI: 10.1016/j.pharmthera.2011.12.008] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 12/15/2011] [Indexed: 12/18/2022]
Abstract
This review focuses on the neurobiology of integrins, pathophysiological roles of integrins in neuroplasticity and nervous system disorders, and therapeutic implications of integrins as potential drug targets and possible delivery pathways. Neuroplasticity is a central phenomenon in many neurological conditions such as seizures, trauma, and traumatic brain injury. During the course of many brain diseases, in addition to intracellular compartment changes, alterations in non-cell compartments such as extracellular matrix (ECM) are recognized as an essential process in forming and reorganizing neural connections. Integrins are heterodimeric transmembrane receptors that mediate cell-ECM and cell-cell adhesion events. Although the mechanisms of neuroplasticity remain unclear, it has been suggested that integrins undergo plasticity including clustering through interactions with ECM proteins, modulating ion channels, intracellular Ca(2+) and protein kinase signaling, and reorganization of cytoskeletal filaments. As cell surface receptors, integrins are central to the pathophysiology of many brain diseases, such as epilepsy, and are potential targets for the development of new drugs for neurological disorders.
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Affiliation(s)
- Xin Wu
- Department of Neuroscience and Experimental Therapeutics, Texas A&M Health Science Center College of Medicine, Bryan, TX 77807, USA
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Abstract
Arterioles are the blood vessels in the arterial side of the vascular tree that are located proximal to the capillaries and, in conjunction with the terminal arteries, provide the majority of resistance to blood flow. Consequently, arterioles are important contributors to the regulation of mean arterial pressure and tissue perfusion. Their wall consists of cellular and extracellular components that have been traditionally classified as conforming three layers: an intima containing endothelial cells sited on a basement membrane; a media made of an internal elastic lamina apposed by one or two layers of smooth muscle; and an adventitia composed mostly of collagen bundles, nerve endings and some fibroblasts. These components of the arteriolar wall are dynamically interconnected, providing a level of plasticity to the arteriolar wall that blurs the traditional boundaries of a rigid layered classification. This MiniReview focuses on the structural conformation of the arteriolar wall and shows how wall components interact spatially, functionally and temporally to control vascular diameter, regulate blood flow and maintain vascular permeability.
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Affiliation(s)
- Luis A Martinez-Lemus
- Department of Medical Pharmacology and Physiology, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO 65211, USA.
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Umesh A, Paudel O, Cao YN, Myers AC, Sham JSK. Alteration of pulmonary artery integrin levels in chronic hypoxia and monocrotaline-induced pulmonary hypertension. J Vasc Res 2011; 48:525-37. [PMID: 21829038 DOI: 10.1159/000329593] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2011] [Accepted: 05/20/2011] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Pulmonary hypertension is associated with vascular remodeling and increased extracellular matrix (ECM) deposition. While the contribution of ECM in vascular remodeling is well documented, the roles played by their receptors, integrins, in pulmonary hypertension have received little attention. Here we characterized the changes of integrin expression in endothelium-denuded pulmonary arteries (PAs) and aorta of chronic hypoxia as well as monocrotaline-treated rats. METHODS AND RESULTS Immunoblot showed increased α(1)-, α(8)- and α(v)-integrins, and decreased α(5)-integrin levels in PAs of both models. β(1)- and β(3)-integrins were reduced in PAs of chronic hypoxia and monocrotaline-treated rats, respectively. Integrin expression in aorta was minimally affected. Differential expression of α(1)- and α(5)-integrins induced by chronic hypoxia was further examined. Immunostaining showed that they were expressed on the surface of PA smooth muscle cells (PASMCs), and their distribution was unaltered by chronic hypoxia. Phosphorylation of focal adhesion kinase was augmented in PAs of chronic hypoxia rats, and in chronic hypoxia PASMCs cultured on the α(1)-ligand collagen IV. Moreover, α(1)-integrin binding hexapeptide GRGDTP elicited an enhanced Ca(2+) response, whereas the response to α(5)-integrin binding peptide GRGDNP was reduced in CH-PASMCs. CONCLUSION Integrins in PASMCs are differentially regulated in pulmonary hypertension, and the dynamic integrin-ECM interactions may contribute to the vascular remodeling accompanying disease progression.
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Affiliation(s)
- Anita Umesh
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins School of Medicine, Baltimore, MD 21224, USA
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Steelman SM, Humphrey JD. Differential remodeling responses of cerebral and skeletal muscle arterioles in a novel organ culture system. Med Biol Eng Comput 2011; 49:1015-23. [PMID: 21786016 DOI: 10.1007/s11517-011-0807-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 07/07/2011] [Indexed: 12/15/2022]
Abstract
Evidence suggests that maladaptive changes in the cerebral microcirculation may contribute to ischemia in numerous diseases. We sought, therefore, to develop an ex vivo organ culture system to study early changes in cerebral arteriolar structure and function, and to compare associated findings to those for non-cerebral arterioles. Pilot studies revealed that rabbit cerebral arterioles maintained contractility longer when cultured in media containing rabbit-specific plasma rather than fetal bovine serum. Cerebral and skeletal muscle arterioles were cultured in a pressure myograph for 5 days; maximum dilatory and contractile responses were measured at 0, 1, 3, and 5 days. Passive properties were preserved in cerebral arterioles over the entire culture period, although skeletal muscle arterioles underwent constrictive remodeling. Cerebral arterioles also maintained a myogenic capability over the entire culture period, albeit at progressively larger diameters, whereas the skeletal muscle arterioles did so only over 3 days. Culture in rabbit serum, which contains numerous growth factors and clotting factors, did not induce or increase inward remodeling in cerebral or skeletal arterioles. These results suggest inherent, organ-specific differences in arteriolar remodeling, and that extensive results in the literature on non-cerebral arterioles should not be extrapolated to predict responses in the cerebral microcirculation.
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Affiliation(s)
- Samantha M Steelman
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, College Station, TX 77843-4458, USA.
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Role of myosin light chain kinase and myosin light chain phosphatase in the resistance arterial myogenic response to intravascular pressure. Arch Biochem Biophys 2011; 510:160-73. [DOI: 10.1016/j.abb.2011.02.024] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 02/24/2011] [Accepted: 02/28/2011] [Indexed: 12/19/2022]
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