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Kucherenko MM, Sang P, Yao J, Gransar T, Dhital S, Grune J, Simmons S, Michalick L, Wulsten D, Thiele M, Shomroni O, Hennig F, Yeter R, Solowjowa N, Salinas G, Duda GN, Falk V, Vyavahare NR, Kuebler WM, Knosalla C. Elastin stabilization prevents impaired biomechanics in human pulmonary arteries and pulmonary hypertension in rats with left heart disease. Nat Commun 2023; 14:4416. [PMID: 37479718 PMCID: PMC10362055 DOI: 10.1038/s41467-023-39934-z] [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: 09/14/2021] [Accepted: 07/04/2023] [Indexed: 07/23/2023] Open
Abstract
Pulmonary hypertension worsens outcome in left heart disease. Stiffening of the pulmonary artery may drive this pathology by increasing right ventricular dysfunction and lung vascular remodeling. Here we show increased stiffness of pulmonary arteries from patients with left heart disease that correlates with impaired pulmonary hemodynamics. Extracellular matrix remodeling in the pulmonary arterial wall, manifested by dysregulated genes implicated in elastin degradation, precedes the onset of pulmonary hypertension. The resulting degradation of elastic fibers is paralleled by an accumulation of fibrillar collagens. Pentagalloyl glucose preserves arterial elastic fibers from elastolysis, reduces inflammation and collagen accumulation, improves pulmonary artery biomechanics, and normalizes right ventricular and pulmonary hemodynamics in a rat model of pulmonary hypertension due to left heart disease. Thus, targeting extracellular matrix remodeling may present a therapeutic approach for pulmonary hypertension due to left heart disease.
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Affiliation(s)
- Mariya M Kucherenko
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Pengchao Sang
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Juquan Yao
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Tara Gransar
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
| | - Saphala Dhital
- Department of Bioengineering, Clemson University, 29634, Clemson, SC, USA
| | - Jana Grune
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Szandor Simmons
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Laura Michalick
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Dag Wulsten
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Mario Thiele
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Orr Shomroni
- NGS Integrative Genomics (NIG), Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Felix Hennig
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Ruhi Yeter
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
| | - Natalia Solowjowa
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
| | - Gabriela Salinas
- NGS Integrative Genomics (NIG), Justus-von-Liebig-Weg 11, 37077, Göttingen, Germany
| | - Georg N Duda
- Julius Wolff Institute for Biomechanics and Musculoskeletal Regeneration, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
- Berlin Institute of Health Center for Regenerative Therapies, Berlin Institute of Health at Charité - Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Volkmar Falk
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany
- Department of Health Science and Technology, Translational Cardiovascular Technology, LFW C 13.2, ETH Zurich, Universitätstrasse 2, 8092, Zürich, Switzerland
| | - Naren R Vyavahare
- Department of Bioengineering, Clemson University, 29634, Clemson, SC, USA
| | - Wolfgang M Kuebler
- Institute of Physiology, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Charitéplatz 1, 10117, Berlin, Germany.
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany.
- Departments of Physiology and Surgery, University of Toronto, 1 King´s College Circle, Toronto, ON M5S 1A8, Canada.
| | - Christoph Knosalla
- Department of Cardiothoracic and Vascular Surgery, Deutsches Herzzentrum der Charité (DHZC), Augustenburger Platz 1, 13353, Berlin, Germany.
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Germany, Charitéplatz 1, 10117, Berlin, Germany.
- DZHK (German Centre for Cardiovascular Research), partner site Berlin, Germany.
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Miklós Z, Horváth I. The Role of Oxidative Stress and Antioxidants in Cardiovascular Comorbidities in COPD. Antioxidants (Basel) 2023; 12:1196. [PMID: 37371927 DOI: 10.3390/antiox12061196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/28/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023] Open
Abstract
Oxidative stress driven by several environmental and local airway factors associated with chronic obstructive bronchiolitis, a hallmark feature of COPD, plays a crucial role in disease pathomechanisms. Unbalance between oxidants and antioxidant defense mechanisms amplifies the local inflammatory processes, worsens cardiovascular health, and contributes to COPD-related cardiovascular dysfunctions and mortality. The current review summarizes recent developments in our understanding of different mechanisms contributing to oxidative stress and its countermeasures, with special attention to those that link local and systemic processes. Major regulatory mechanisms orchestrating these pathways are also introduced, with some suggestions for further research in the field.
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Affiliation(s)
- Zsuzsanna Miklós
- National Korányi Institute for Pulmonology, Korányi F. Street 1, H-1121 Budapest, Hungary
| | - Ildikó Horváth
- National Korányi Institute for Pulmonology, Korányi F. Street 1, H-1121 Budapest, Hungary
- Department of Pulmonology, University of Debrecen, Nagyerdei krt 98, H-4032 Debrecen, Hungary
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Allen BJ, Frye H, Ramanathan R, Caggiano LR, Tabima DM, Chesler NC, Philip JL. Biomechanical and Mechanobiological Drivers of the Transition From PostCapillary Pulmonary Hypertension to Combined Pre-/PostCapillary Pulmonary Hypertension. J Am Heart Assoc 2023; 12:e028121. [PMID: 36734341 PMCID: PMC9973648 DOI: 10.1161/jaha.122.028121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Combined pre-/postcapillary pulmonary hypertension (Cpc-PH), a complication of left heart failure, is associated with higher mortality rates than isolated postcapillary pulmonary hypertension alone. Currently, knowledge gaps persist on the mechanisms responsible for the progression of isolated postcapillary pulmonary hypertension (Ipc-PH) to Cpc-PH. Here, we review the biomechanical and mechanobiological impact of left heart failure on pulmonary circulation, including mechanotransduction of these pathological forces, which lead to altered biological signaling and detrimental remodeling, driving the progression to Cpc-PH. We focus on pathologically increased cyclic stretch and decreased wall shear stress; mechanotransduction by endothelial cells, smooth muscle cells, and pulmonary arterial fibroblasts; and signaling-stimulated remodeling of the pulmonary veins, capillaries, and arteries that propel the transition from Ipc-PH to Cpc-PH. Identifying biomechanical and mechanobiological mechanisms of Cpc-PH progression may highlight potential pharmacologic avenues to prevent right heart failure and subsequent mortality.
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Affiliation(s)
- Betty J. Allen
- Department of SurgeryUniversity of Wisconsin‐MadisonMadisonWI
| | - Hailey Frye
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI
| | - Rasika Ramanathan
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI
| | - Laura R. Caggiano
- Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center and Department of Biomedical EngineeringUniversity of CaliforniaIrvineCA
| | - Diana M. Tabima
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI
| | - Naomi C. Chesler
- Department of Biomedical EngineeringUniversity of Wisconsin‐MadisonMadisonWI
- Edwards Lifesciences Foundation Cardiovascular Innovation and Research Center and Department of Biomedical EngineeringUniversity of CaliforniaIrvineCA
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Tsarova K, Morgan AE, Melendres-Groves L, Ibrahim MM, Ma CL, Pan IZ, Hatton ND, Beck EM, Ferrel MN, Selzman CH, Ingram D, Alamri AK, Ratcliffe MB, Wilson BD, Ryan JJ. Imaging in Pulmonary Vascular Disease-Understanding Right Ventricle-Pulmonary Artery Coupling. Compr Physiol 2022; 12:3705-3730. [PMID: 35950653 DOI: 10.1002/cphy.c210017] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The right ventricle (RV) and pulmonary arterial (PA) tree are inextricably linked, continually transferring energy back and forth in a process known as RV-PA coupling. Healthy organisms maintain this relationship in optimal balance by modulating RV contractility, pulmonary vascular resistance, and compliance to sustain RV-PA coupling through life's many physiologic challenges. Early in states of adaptation to cardiovascular disease-for example, in diastolic heart failure-RV-PA coupling is maintained via a multitude of cellular and mechanical transformations. However, with disease progression, these compensatory mechanisms fail and become maladaptive, leading to the often-fatal state of "uncoupling." Noninvasive imaging modalities, including echocardiography, magnetic resonance imaging, and computed tomography, allow us deeper insight into the state of coupling for an individual patient, providing for prognostication and potential intervention before uncoupling occurs. In this review, we discuss the physiologic foundations of RV-PA coupling, elaborate on the imaging techniques to qualify and quantify it, and correlate these fundamental principles with clinical scenarios in health and disease. © 2022 American Physiological Society. Compr Physiol 12: 1-26, 2022.
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Affiliation(s)
- Katsiaryna Tsarova
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Ashley E Morgan
- Division of Cardiothoracic Surgery, Department of Surgery, University of Utah, Salt Lake City, Utah, USA
| | - Lana Melendres-Groves
- Division of Pulmonary and Critical Care Medicine, University of New Mexico, Albuquerque, New Mexico, USA
| | - Majd M Ibrahim
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Christy L Ma
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Irene Z Pan
- Department of Pharmacy, University of Utah Health, Salt Lake City, Utah, USA
| | - Nathan D Hatton
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Emily M Beck
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Utah, Salt Lake City, Utah, USA
| | - Meganne N Ferrel
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Craig H Selzman
- Division of Cardiothoracic Surgery, Department of Surgery, University of Utah, Salt Lake City, Utah, USA
| | - Dominique Ingram
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - Ayedh K Alamri
- Department of Medicine, University of Utah, Salt Lake City, Utah, USA
| | | | - Brent D Wilson
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - John J Ryan
- Division of Cardiovascular Medicine, Department of Medicine, University of Utah School of Medicine, Salt Lake City, Utah, USA
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Hsu CH, Roan JN, Fang SY, Chiu MH, Cheng TT, Huang CC, Lin MW, Lam CF. Transplantation of viable mitochondria improves right ventricular performance and pulmonary artery remodeling in rats with pulmonary arterial hypertension. J Thorac Cardiovasc Surg 2022; 163:e361-e373. [PMID: 32948302 DOI: 10.1016/j.jtcvs.2020.08.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/28/2020] [Accepted: 08/04/2020] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Because mitochondrial dysfunction is a key factor in the progression of pulmonary hypertension, this study tested the hypothesis that transplantation of exogenous viable mitochondria can reverse pulmonary artery remodeling and restore right ventricular performance in pulmonary hypertension. METHODS Pulmonary hypertension was induced by parenteral injection of monocrotaline (60 mg/kg) and creation of a left-to-right shunt aortocaval fistula in rats. Three weeks after creation of fistula, the animals were randomly assigned to receive intravenous delivery of placebo solution or allogeneic mitochondria once weekly for 3 consecutive weeks. Mitochondria (100 μg) were isolated from the freshly harvested soleus muscles of naïve rats. Transthoracic echocardiography was performed at 3 weeks after mitochondrial delivery. RESULTS Ex vivo heart-lung block images acquired by an IVIS Spectrum (PerkinElmer, Waltham, Mass) imaging system confirmed the enhancement of MitoTracker (Invitrogen, Carlsbad, Calif) fluorescence in the pulmonary arteries. Mitochondria transplantation significantly increased lung tissue adenosine triphosphate concentrations and improved right ventricular performance, as evidenced by a reduction in serum levels of B-type natriuretic peptide and ventricular diameter. Right ventricular mass and wall thickness were restored in the mitochondrial group. In the pulmonary arteries of rats that received mitochondrial treatment, vascular smooth muscle cells expressed higher levels of α-smooth muscle actin and smooth muscle myosin heavy chain II, indicating the maintenance of the nonproliferative, contractile phenotype. The hyper-reactivity of isolated pulmonary arteries to α-adrenergic stimulation was also attenuated after mitochondrial transplantation. CONCLUSIONS Transplantation of viable mitochondria can restore the contractile phenotype and vasoreactivity of the pulmonary artery, thereby reducing the afterload and right ventricular remodeling in rats with established pulmonary hypertension. The improvement in overall right ventricular performance suggests that mitochondrial transplantation can be a revolutionary clinical therapeutic option for the management of pulmonary hypertension.
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Affiliation(s)
- Chih-Hsin Hsu
- Department of Internal Medicine, National Cheng Kung University Hospital and College of Medicine, Tainan, Taiwan; Department of Internal Medicine, National Cheng Kung University Hospital, Dou-Liou Branch, Yunlin, Taiwan
| | - Jun-Neng Roan
- Division of Cardiovascular Surgery, Department of Surgery, National Cheng Kung University Hospital and College of Medicine, Tainan, Taiwan
| | - Shih-Yuan Fang
- Department of Anesthesiology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Meng-Hsuan Chiu
- Department of Anesthesiology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Tzu-Ting Cheng
- Department of Anesthesiology, E-Da Hospital and E-Da Cancer Hospital, Kaohsiung, Taiwan
| | - Chien-Chi Huang
- Department of Medical Research, E-Da Hospital and E-Da Cancer Hospital, Kaohsiung, Taiwan
| | - Ming-Wei Lin
- Department of Respiratory Therapy, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Medical Research, E-Da Hospital and E-Da Cancer Hospital, Kaohsiung, Taiwan; School of Medicine, I-Shou University College of Medicine, Kaohsiung, Taiwan
| | - Chen-Fuh Lam
- Department of Anesthesiology, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Anesthesiology, E-Da Hospital and E-Da Cancer Hospital, Kaohsiung, Taiwan; School of Medicine, I-Shou University College of Medicine, Kaohsiung, Taiwan.
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Meki M, El-Baz A, Sethu P, Giridharan G. Effects of Pulsatility on Arterial Endothelial and Smooth Muscle Cells. Cells Tissues Organs 2022; 212:272-284. [PMID: 35344966 PMCID: PMC10782761 DOI: 10.1159/000524317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 03/16/2022] [Indexed: 01/04/2023] Open
Abstract
Continuous flow ventricular assist device (CFVAD) support in advanced heart failure patients causes diminished pulsatility, which has been associated with adverse events including gastrointestinal bleeding, end organ failure, and arteriovenous malformation. Recently, pulsatility augmentation by pump speed modulation has been proposed as a means to minimize adverse events. Pulsatility primarily affects endothelial and smooth muscle cells in the vasculature. To study the effects of pulsatility and pulse modulation using CFVADs, we have developed a microfluidic co-culture model with human aortic endothelial (ECs) and smooth muscle cells (SMCs) that can replicate physiologic pressures, flows, shear stresses, and cyclical stretch. The effects of pulsatility and pulse frequency on ECs and SMCs were evaluated during (1) normal pulsatile flow (120/80 mmHg, 60 bpm), (2) diminished pulsatility (98/92 mmHg, 60 bpm), and (3) low cyclical frequency (115/80 mmHg, 30 bpm). Shear stresses were estimated using computational fluid dynamics (CFD) simulations. While average shear stresses (4.2 dynes/cm2) and flows (10.1 mL/min) were similar, the peak shear stresses for normal pulsatile flow (16.9 dynes/cm2) and low cyclic frequency (19.5 dynes/cm2) were higher compared to diminished pulsatility (6.45 dynes/cm2). ECs and SMCs demonstrated significantly lower cell size with diminished pulsatility compared to normal pulsatile flow. Low cyclical frequency resulted in normalization of EC cell size but not SMCs. SMCs size was higher with low frequency condition compared to diminished pulsatility but did not normalize to normal pulsatility condition. These results may suggest that pressure amplitude augmentation may have a greater effect in normalizing ECs, while both pressure amplitude and frequency may be required to normalize SMCs morphology. The co-culture model may be an ideal platform to study flow modulation strategies.
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Affiliation(s)
- Moustafa Meki
- Bioengineering, University of Louisville, Louisville, KY, USA
| | - Ayman El-Baz
- Bioengineering, University of Louisville, Louisville, KY, USA
| | - Palanaippan Sethu
- Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, USA
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Dieffenbach PB, Aravamudhan A, Fredenburgh LE, Tschumperlin DJ. The Mechanobiology of Vascular Remodeling in the Aging Lung. Physiology (Bethesda) 2022; 37:28-38. [PMID: 34514871 PMCID: PMC8742727 DOI: 10.1152/physiol.00019.2021] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Aging is accompanied by declining lung function and increasing susceptibility to lung diseases. The role of endothelial dysfunction and vascular remodeling in these changes is supported by growing evidence, but underlying mechanisms remain elusive. In this review we summarize functional, structural, and molecular changes in the aging pulmonary vasculature and explore how interacting aging and mechanobiological cues may drive progressive vascular remodeling in the lungs.
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Affiliation(s)
- Paul B. Dieffenbach
- 1Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
| | - Aja Aravamudhan
- 2Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota
| | - Laura E. Fredenburgh
- 1Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
| | - Daniel J. Tschumperlin
- 2Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, Minnesota
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Chalkiadaki K, Statoulla E, Markou M, Bellou S, Bagli E, Fotsis T, Murphy C, Gkogkas CG. Translational control in neurovascular brain development. ROYAL SOCIETY OPEN SCIENCE 2021; 8:211088. [PMID: 34659781 PMCID: PMC8511748 DOI: 10.1098/rsos.211088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/23/2021] [Indexed: 06/13/2023]
Abstract
The human brain carries out complex tasks and higher functions and is crucial for organismal survival, as it senses both intrinsic and extrinsic environments. Proper brain development relies on the orchestrated development of different precursor cells, which will give rise to the plethora of mature brain cell-types. Within this process, neuronal cells develop closely to and in coordination with vascular cells (endothelial cells (ECs), pericytes) in a bilateral communication process that relies on neuronal activity, attractive or repulsive guidance cues for both cell types and on tight-regulation of gene expression. Translational control is a master regulator of the gene-expression pathway and in particular for neuronal and ECs, it can be localized in developmentally relevant (axon growth cone, endothelial tip cell) and mature compartments (synapses, axons). Herein, we will review mechanisms of translational control relevant to brain development in neurons and ECs in health and disease.
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Affiliation(s)
- Kleanthi Chalkiadaki
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Elpida Statoulla
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Maria Markou
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Sofia Bellou
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Eleni Bagli
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Theodore Fotsis
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Carol Murphy
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
| | - Christos G. Gkogkas
- Division of Biomedical Research, Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, University Campus, 45110 Ioannina, Greece
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Röhl S, Suur BE, Lengquist M, Seime T, Caidahl K, Hedin U, Arner A, Matic L, Razuvaev A. Lack of PCSK6 Increases Flow-Mediated Outward Arterial Remodeling in Mice. Cells 2020; 9:cells9041009. [PMID: 32325687 PMCID: PMC7225991 DOI: 10.3390/cells9041009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 04/14/2020] [Accepted: 04/16/2020] [Indexed: 12/17/2022] Open
Abstract
Proprotein convertases (PCSKs) process matrix metalloproteases and cytokines, but their function in the vasculature is largely unknown. Previously, we demonstrated upregulation of PCSK6 in atherosclerotic plaques from symptomatic patients, localization to smooth muscle cells (SMCs) in the fibrous cap and positive correlations with inflammation, extracellular matrix remodeling and cytokines. Here, we hypothesize that PCSK6 could be involved in flow-mediated vascular remodeling and aim to evaluate its role in the physiology of this process using knockout mice. Pcsk6−/− and wild type mice were randomized into control and increased blood flow groups and induced in the right common carotid artery (CCA) by ligation of the left CCA. The animals underwent repeated ultrasound biomicroscopy (UBM) examinations followed by euthanization with subsequent evaluation using wire myography, transmission electron microscopy or histology. The Pcsk6−/− mice displayed a flow-mediated increase in lumen circumference over time, assessed with UBM. Wire myography revealed differences in the flow-mediated remodeling response detected as an increase in lumen circumference at optimal stretch with concomitant reduction in active tension. Furthermore, a flow-mediated reduction in expression of SMC contractile markers SMA, MYH11 and LMOD1 was seen in the Pcsk6−/− media. Absence of PCSK6 increases outward remodeling and reduces medial contractility in response to increased blood flow.
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Affiliation(s)
- Samuel Röhl
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
| | - Bianca E. Suur
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
| | - Mariette Lengquist
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
| | - Till Seime
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
| | - Kenneth Caidahl
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
- Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, 413 45 Gothenburg, Sweden
| | - Ulf Hedin
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
| | - Anders Arner
- Department of Clinical Sciences Lund, Thoracic Surgery, Lund University, 221 84 Lund, Sweden;
| | - Ljubica Matic
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
- Correspondence: (L.M.); (A.R.); Tel.: +46-(0)-73-962-42-79 (L.M.); +46-(0)-76-238-44-75 (A.R.)
| | - Anton Razuvaev
- Department of Molecular Medicine and Surgery, Karolinska Institutet, 171 76 Stockholm, Sweden; (S.R.); (B.E.S.); (M.L.); (T.S.); (K.C.); (U.H.)
- Correspondence: (L.M.); (A.R.); Tel.: +46-(0)-73-962-42-79 (L.M.); +46-(0)-76-238-44-75 (A.R.)
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10
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Elliott W, Guo D, Veldtman G, Tan W. Effect of Viscoelasticity on Arterial-Like Pulsatile Flow Dynamics and Energy. J Biomech Eng 2020; 142:041001. [PMID: 31523750 PMCID: PMC7104782 DOI: 10.1115/1.4044877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 08/16/2019] [Indexed: 11/08/2022]
Abstract
Time-dependent arterial wall property is an important but difficult topic in vascular mechanics. Hysteresis, which appears during the measurement of arterial pressure-diameter relationship through a cardiac cycle, has been used to indicate time-dependent mechanics of arteries. However, the cause-effect relationship between viscoelastic (VE) properties of the arterial wall and hemodynamics, particularly the viscous contribution to hemodynamics, remains challenging. Herein, we show direct comparisons between elastic (E) (loss/storage < 0.1) and highly viscoelastic (loss/storage > 0.45) conduit structures with arterial-like compliance, in terms of their capability of altering pulsatile flow, wall shear, and energy level. Conduits were made from varying ratio of vinyl- and methyl-terminated poly(dimethylsiloxane) and were fit in a mimetic circulatory system measuring volumetric flow, pressure, and strain. Results indicated that when compared to elastic conduits, viscoelastic conduits attenuated lumen distension waveforms, producing an average of 11% greater cross-sectional area throughout a mimetic cardiac cycle. In response to such changes in lumen diameter strain, pressure and volumetric flow waves in viscoelastic conduits decreased by 3.9% and 6%, respectively, in the peak-to-peak amplitude. Importantly, the pulsatile waveforms for both diameter strain and volumetric flow demonstrated greater temporal alignment in viscoelastic conduits due to pulsation attenuation, resulting in 25% decrease in the oscillation of wall shear stress (WSS). We hope these findings may be used to further examine time-dependent arterial properties in disease prognosis and progression, as well as their use in vascular graft design.
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Affiliation(s)
- Winston Elliott
- Department of Mechanical Engineering, University of Colorado at
Boulder, 1111 Engineering Drive, ECME 114,
Boulder, CO 80309
| | - Dongjie Guo
- Department of Mechanical Engineering, University of Colorado at
Boulder, 1111 Engineering Drive, ECME 114,
Boulder, CO 80309; State Laboratory
of Surface and Interface, Zhengzhou University of Light
Industry, Zhengzhou 450002
China
| | - Gruschen Veldtman
- Department of Pediatrics, Cincinnati Children's
Hospital, University of Cincinnati, 3333 Burnet Ave,
Cincinnati, OH 45229
| | - Wei Tan
- Department of Mechanical Engineering, University of Colorado at
Boulder, 1111 Engineering Drive, ECME 114,
Boulder, CO 80309
e-mail:
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11
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Frump AL, Lahm T. Tips for success in pulmonary hypertension treatment: progress in isolating endothelial cells from pulmonary artery catheters. Eur Respir J 2020; 55:55/3/2000122. [PMID: 32198271 DOI: 10.1183/13993003.00122-2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 01/21/2020] [Indexed: 11/05/2022]
Affiliation(s)
- Andrea L Frump
- Division of Pulmonary, Critical Care, Sleep and Occupational Medicine, Dept of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Tim Lahm
- Division of Pulmonary, Critical Care, Sleep and Occupational Medicine, Dept of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA.,Richard L. Roudebush VA Medical Center, Indiana University, Indianapolis, IN, USA
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12
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Simpson LJ, Reader JS, Tzima E. Mechanical Regulation of Protein Translation in the Cardiovascular System. Front Cell Dev Biol 2020; 8:34. [PMID: 32083081 PMCID: PMC7006472 DOI: 10.3389/fcell.2020.00034] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 01/15/2020] [Indexed: 12/12/2022] Open
Abstract
The cardiovascular system can sense and adapt to changes in mechanical stimuli by remodeling the physical properties of the heart and blood vessels in order to maintain homeostasis. Imbalances in mechanical forces and/or impaired sensing are now not only implicated but are, in some cases, considered to be drivers for the development and progression of cardiovascular disease. There is now growing evidence to highlight the role of mechanical forces in the regulation of protein translation pathways. The canonical mechanism of protein synthesis typically involves transcription and translation. Protein translation occurs globally throughout the cell to maintain general function but localized protein synthesis allows for precise spatiotemporal control of protein translation. This Review will cover studies on the role of biomechanical stress -induced translational control in the heart (often in the context of physiological and pathological hypertrophy). We will also discuss the much less studied effects of mechanical forces in regulating protein translation in the vasculature. Understanding how the mechanical environment influences protein translational mechanisms in the cardiovascular system, will help to inform disease pathogenesis and potential areas of therapeutic intervention.
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Affiliation(s)
- Lisa J Simpson
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - John S Reader
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Ellie Tzima
- Division of Cardiovascular Medicine, Radcliffe Department of Medicine, Wellcome Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
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13
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Latorre M, Bersi MR, Humphrey JD. Computational Modeling Predicts Immuno-Mechanical Mechanisms of Maladaptive Aortic Remodeling in Hypertension. INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE 2019; 141:35-46. [PMID: 32831391 PMCID: PMC7437922 DOI: 10.1016/j.ijengsci.2019.05.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Uncontrolled hypertension is a major risk factor for myriad cardiovascular diseases. Among its many effects, hypertension increases central artery stiffness which in turn is both an initiator and indicator of disease. Despite extensive clinical, animal, and basic science studies, the biochemomechanical mechanisms by which hypertension drives aortic stiffening remain unclear. In this paper, we show that a new computational model of aortic growth and remodeling can capture differential effects of induced hypertension on the thoracic and abdominal aorta in a common mouse model of disease. Because the simulations treat the aortic wall as a constrained mixture of different constituents having different material properties and rates of turnover, one can gain increased insight into underlying constituent-level mechanisms of aortic remodeling. Model results suggest that the aorta can mechano-adapt locally to blood pressure elevation in the absence of marked inflammation, but large increases in inflammation drive a persistent maladaptive phenotype characterized primarily by adventitial fibrosis. Moreover, this fibrosis appears to occur via a marked increase in the rate of deposition of collagen having different material properties in the absence of a compensatory increase in the rate of matrix degradation. Controlling inflammation thus appears to be key to reducing fibrosis, but therapeutic strategies should not compromise the proteolytic activity of the wall that is essential to mechanical homeostasis.
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Affiliation(s)
- Marcos Latorre
- Department of Biomedical Engineering Yale University, New Haven, CT, USA
| | - Matthew R. Bersi
- Department of Biomedical Engineering Vanderbilt University, Nashville, TN, USA
| | - Jay D. Humphrey
- Department of Biomedical Engineering Yale University, New Haven, CT, USA
- Vascular Biology and Therapeutics Program Yale School of Medicine, New Haven, CT, USA
- Corresponding author: (Jay D. Humphrey)
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14
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Wu D, Birukov K. Endothelial Cell Mechano-Metabolomic Coupling to Disease States in the Lung Microvasculature. Front Bioeng Biotechnol 2019; 7:172. [PMID: 31380363 PMCID: PMC6658821 DOI: 10.3389/fbioe.2019.00172] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/03/2019] [Indexed: 12/15/2022] Open
Abstract
Lungs are the most vascular part of humans, accepting the totality of cardiac output in a volume much smaller than the body itself. Due to this cardiac output, the lung microvasculature is subject to mechanical forces including shear stress and cyclic stretch that vary with the cardiac and breathing cycle. Vessels are surrounded by extracellular matrix which dictates the stiffness which endothelial cells also sense and respond to. Shear stress, stiffness, and cyclic stretch are known to influence endothelial cell state. At high shear stress, endothelial cells exhibit cell quiescence marked by low inflammatory markers and high nitric oxide synthesis, whereas at low shear stress, endothelial cells are thought to "activate" into a pro-inflammatory state and have low nitric oxide. Shear stress' profound effect on vascular phenotype is most apparent in the arterial vasculature and in the pathophysiology of vascular inflammation. To conduct the flow of blood from the right heart, the lung microvasculature must be rigid yet compliant. It turns out that excessive substrate rigidity or stiffness is important in the development of pulmonary hypertension and chronic fibrosing lung diseases via excessive cell proliferation or the endothelial-mesenchymal transition. Recently, a new body of literature has evolved that couples mechanical sensing to endothelial phenotypic changes through metabolic signaling in clinically relevant contexts such as pulmonary hypertension, lung injury syndromes, as well as fibrosis, which is the focus of this review. Stretch, like flow, has profound effect on endothelial phenotype; metabolism studies due to stretch are in their infancy.
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Affiliation(s)
- David Wu
- Section of Pulmonary and Critical Care, Department of Medicine, University of Chicago, Chicago, IL, United States
| | - Konstantin Birukov
- Department of Anesthesia, University of Maryland, Baltimore, MD, United States
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15
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Friesen RM, Schäfer M, Ivy DD, Abman SH, Stenmark K, Browne LP, Barker AJ, Hunter KS, Truong U. Proximal pulmonary vascular stiffness as a prognostic factor in children with pulmonary arterial hypertension. Eur Heart J Cardiovasc Imaging 2019; 20:209-217. [PMID: 29788051 DOI: 10.1093/ehjci/jey069] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 04/23/2018] [Indexed: 11/12/2022] Open
Abstract
Aims Main pulmonary artery (MPA) stiffness and abnormal flow haemodynamics in pulmonary arterial hypertension (PAH) are strongly associated with elevated right ventricular (RV) afterload and associated with disease severity and poor clinical outcomes in adults with PAH. However, the long-term effects of MPA stiffness on RV function in children with PAH remain poorly understood. This study is the first comprehensive evaluation of MPA stiffness in children with PAH, delineating the mechanistic relationship between flow haemodynamics and MPA stiffness as well as the prognostic ability of these measures regarding clinical outcomes. Methods and results Fifty-six children diagnosed with PAH underwent baseline cardiac magnetic resonance (CMR) acquisition and were compared with 23 control subjects. MPA stiffness and wall shear stress (WSS) were evaluated using phase contrast CMR and were evaluated for prognostic potential along with standard RV volumetric and functional indices. Pulse wave velocity (PWV) was significantly increased (2.8 m/s vs. 1.4 m/s, P < 0.0001) and relative area change (RAC) was decreased (25% vs. 37%, P < 0.0001) in the PAH group, correlating with metrics of RV performance. Decreased WSS was associated with a decrease in RAC over time (r = 0.679, P < 0.001). For each unit increase in PWV, there was approximately a 3.2-fold increase in having a moderate clinical event. Conclusion MPA stiffness assessed by non-invasive CMR was increased in children with PAH and correlated with RV performance, suggesting that MPA stiffness is a major contribution to RV dysfunction. PWV is predictive of moderate clinical outcomes, and may be a useful prognostic marker of disease activity in children with PAH.
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Affiliation(s)
- Richard M Friesen
- Division of Cardiology, Heart Institute, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA.,Department of Critical Care, Seattle Children's Hospital, University of Washington, 4800 Sand Point Way NE, Seattle, WA, USA
| | - Michal Schäfer
- Division of Cardiology, Heart Institute, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA.,Department of Bioengineering, College of Engineering and Applied Sciences, University of Colorado Denver, Anschutz Medical Campus, 12705 E. Montview Ave, Aurora, CO, USA
| | - D Dunbar Ivy
- Division of Cardiology, Heart Institute, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA
| | - Steven H Abman
- Division of Pulmonology, Breathing Institute, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA
| | - Kurt Stenmark
- Developmental Lung Biology and Cardiovascular Pulmonary Research Laboratories, University of Colorado Denver, Anschutz Medical Campus, 12700 E 19th Ave, Box B131. Aurora, CO, USA
| | - Lorna P Browne
- Department of Radiology, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA
| | - Alex J Barker
- Department of Radiology, Feinberg School of Medicine, Northwestern University, 737 N Michigan Ave, Suite 1600, Chicago, IL, USA
| | - Kendall S Hunter
- Division of Cardiology, Heart Institute, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA.,Department of Bioengineering, College of Engineering and Applied Sciences, University of Colorado Denver, Anschutz Medical Campus, 12705 E. Montview Ave, Aurora, CO, USA
| | - Uyen Truong
- Division of Cardiology, Heart Institute, Children's Hospital Colorado, University of Colorado Denver, Anschutz Medical Campus, 13123 E 16th Avenue, Aurora, CO, USA
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16
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Thenappan T, Chan SY, Weir EK. Role of extracellular matrix in the pathogenesis of pulmonary arterial hypertension. Am J Physiol Heart Circ Physiol 2018; 315:H1322-H1331. [PMID: 30141981 PMCID: PMC6297810 DOI: 10.1152/ajpheart.00136.2018] [Citation(s) in RCA: 128] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 08/06/2018] [Accepted: 08/14/2018] [Indexed: 12/23/2022]
Abstract
Pulmonary arterial hypertension (PAH) is characterized by remodeling of the extracellular matrix (ECM) of the pulmonary arteries with increased collagen deposition, cross-linkage of collagen, and breakdown of elastic laminae. Extracellular matrix remodeling occurs due to an imbalance in the proteolytic enzymes, such as matrix metalloproteinases, elastases, and lysyl oxidases, and tissue inhibitor of matrix metalloproteinases, which, in turn, results from endothelial cell dysfunction, endothelial-to-mesenchymal transition, and inflammation. ECM remodeling and pulmonary vascular stiffness occur early in the disease process, before the onset of the increase in the intimal and medial thickness and pulmonary artery pressure, suggesting that the ECM is a cause rather than a consequence of distal pulmonary vascular remodeling. ECM remodeling and increased pulmonary arterial stiffness promote proliferation of pulmonary vascular cells (endothelial cells, smooth muscle cells, and adventitial fibroblasts) through mechanoactivation of various signaling pathways, including transcriptional cofactors YAP/TAZ, transforming growth factor-β, transient receptor potential channels, Toll-like receptor, and NF-κB. Inhibition of ECM remodeling and mechanotransduction prevents and reverses experimental pulmonary hypertension. These data support a central role for ECM remodeling in the pathogenesis of the PAH, making it an attractive novel therapeutic target.
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Affiliation(s)
- Thenappan Thenappan
- Cardiovascular Division, Department of Medicine, University of Minnesota , Minneapolis, Minnesota
| | - Stephen Y Chan
- Center for Pulmonary Vascular Biology and Medicine, Pittsburgh Heart, Lung, Blood, and Vascular Medicine Institute, Division of Cardiology, Department of Medicine, University of Pittsburgh School of Medicine, Pennsylvania
- University of Pittsburgh Medical Center, Pennsylvania
| | - E Kenneth Weir
- Cardiovascular Division, Department of Medicine, University of Minnesota , Minneapolis, Minnesota
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17
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Pulmonary Vascular Platform Models the Effects of Flow and Pressure on Endothelial Dysfunction in BMPR2 Associated Pulmonary Arterial Hypertension. Int J Mol Sci 2018; 19:ijms19092561. [PMID: 30158434 PMCID: PMC6164056 DOI: 10.3390/ijms19092561] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/22/2018] [Accepted: 08/22/2018] [Indexed: 12/15/2022] Open
Abstract
Endothelial dysfunction is a known consequence of bone morphogenetic protein type II receptor (BMPR2) mutations seen in pulmonary arterial hypertension (PAH). However, standard 2D cell culture models fail to mimic the mechanical environment seen in the pulmonary vasculature. Hydrogels have emerged as promising platforms for 3D disease modeling due to their tunable physical and biochemical properties. In order to recreate the mechanical stimuli seen in the pulmonary vasculature, we have created a novel 3D hydrogel-based pulmonary vasculature model (“artificial arteriole”) that reproduces the pulsatile flow rates and pressures seen in the human lung. Using this platform, we studied both Bmpr2R899X and WT endothelial cells to better understand how the addition of oscillatory flow and physiological pressure influenced gene expression, cell morphology, and cell permeability. The addition of oscillatory flow and pressure resulted in several gene expression changes in both WT and Bmpr2R899X cells. However, for many pathways with relevance to PAH etiology, Bmpr2R899X cells responded differently when compared to the WT cells. Bmpr2R899X cells were also found not to elongate in the direction of flow, and instead remained stagnant in morphology despite mechanical stimuli. The increased permeability of the Bmpr2R899X layer was successfully reproduced in our artificial arteriole, with the addition of flow and pressure not leading to significant changes in permeability. Our artificial arteriole is the first to model many mechanical properties seen in the lung. Its tunability enables several new opportunities to study the endothelium in pulmonary vascular disease with increased control over environmental parameters.
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18
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Dieffenbach PB, Maracle M, Tschumperlin DJ, Fredenburgh LE. Mechanobiological Feedback in Pulmonary Vascular Disease. Front Physiol 2018; 9:951. [PMID: 30090065 PMCID: PMC6068271 DOI: 10.3389/fphys.2018.00951] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/28/2018] [Indexed: 01/06/2023] Open
Abstract
Vascular stiffening in the pulmonary arterial bed is increasingly recognized as an early disease marker and contributor to right ventricular workload in pulmonary hypertension. Changes in pulmonary artery stiffness throughout the pulmonary vascular tree lead to physiologic alterations in pressure and flow characteristics that may contribute to disease progression. These findings have led to a greater focus on the potential contributions of extracellular matrix remodeling and mechanical signaling to pulmonary hypertension pathogenesis. Several recent studies have demonstrated that the cellular response to vascular stiffness includes upregulation of signaling pathways that precipitate further vascular remodeling, a process known as mechanobiological feedback. The extracellular matrix modifiers, mechanosensors, and mechanotransducers responsible for this process have become increasingly well-recognized. In this review, we discuss the impact of vascular stiffening on pulmonary hypertension morbidity and mortality, evidence in favor of mechanobiological feedback in pulmonary hypertension pathogenesis, and the major contributors to mechanical signaling in the pulmonary vasculature.
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Affiliation(s)
- Paul B Dieffenbach
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA, United States
| | - Marcy Maracle
- Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Daniel J Tschumperlin
- Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine and Science, Rochester, MN, United States
| | - Laura E Fredenburgh
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA, United States
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19
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Schäfer M, Ivy DD, Barker AJ, Kheyfets V, Shandas R, Abman SH, Hunter KS, Truong U. Characterization of CMR-derived haemodynamic data in children with pulmonary arterial hypertension. Eur Heart J Cardiovasc Imaging 2018; 18:424-431. [PMID: 27444679 DOI: 10.1093/ehjci/jew152] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 06/28/2016] [Indexed: 12/30/2022] Open
Abstract
Aims Paediatric pulmonary arterial hypertension (PAH) is manifested as increased arterial pressure and vascular resistive changes followed by progressive arterial stiffening. The aim of this study was to characterize regional flow haemodynamic patterns and markers of vascular stiffness in the proximal pulmonary arteries of paediatric PAH patients, and to explore the association with right ventricular (RV) function. Methods and results Forty paediatric PAH patients and 26 age- and size-matched controls underwent cardiac magnetic resonance studies in order to compute time-resolved wall shear stress metrics, oscillatory shear index (OSI), and vascular strain as measured by relative area change (RAC), and RV volumetric and functional parameters. Phase-contrast imaging planes were positioned perpendicular to the mid-main and right pulmonary arteries (MPA and RPA, respectively). Compared with controls, the PAH group had decreased systolic wall shear stress (dyne cm-2) and RAC (%) in both MPA (WSSsys: 6.5 vs. 4.3, P < 0.0001; RAC: 36 vs. 25, P < 0.0001) and RPA (WSSsys: 11.2 vs. 7.3, P < 0.0001; strain: 37 vs. 30, P < 0.05). The OSI was significantly higher in the MPA of PAH subjects (0.46 vs. 0.17, P < 0.05). WSS measured in the MPA correlated positively with RAC (r = 0.63, P < 0.0001) and RV ejection fraction (%) (r = 0.63, P < 0.0001). Conclusion Wall shear stress, the principal haemodynamic force driving endothelial functional changes, is severely decreased in paediatric PAH patients and correlates with increased stiffness in the proximal pulmonary vasculature and reduced RV function.
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Affiliation(s)
- Michal Schäfer
- Department of Pediatrics, Section of Cardiology, Children's Hospital Colorado, Denver-Aurora, CO, USA.,Department of Bioengineering, University of Colorado, Research 2 - Building P15, Anschutz Medical Campus, 12700 E 19th Avenue, Aurora, CO 80045-2560, USA
| | - D Dunbar Ivy
- Department of Pediatrics, Section of Cardiology, Children's Hospital Colorado, Denver-Aurora, CO, USA
| | - Alex J Barker
- Department of Radiology, Northwestern University, Chicago, IL, USA
| | - Vitaly Kheyfets
- Department of Bioengineering, University of Colorado, Research 2 - Building P15, Anschutz Medical Campus, 12700 E 19th Avenue, Aurora, CO 80045-2560, USA
| | - Robin Shandas
- Department of Bioengineering, University of Colorado, Research 2 - Building P15, Anschutz Medical Campus, 12700 E 19th Avenue, Aurora, CO 80045-2560, USA
| | - Steven H Abman
- Department of Pediatrics, Section of Pulmonology, Children's Hospital Colorado, Denver-Aurora, CO, USA
| | - Kendall S Hunter
- Department of Pediatrics, Section of Cardiology, Children's Hospital Colorado, Denver-Aurora, CO, USA.,Department of Bioengineering, University of Colorado, Research 2 - Building P15, Anschutz Medical Campus, 12700 E 19th Avenue, Aurora, CO 80045-2560, USA
| | - Uyen Truong
- Department of Pediatrics, Section of Cardiology, Children's Hospital Colorado, Denver-Aurora, CO, USA.,Department of Bioengineering, University of Colorado, Research 2 - Building P15, Anschutz Medical Campus, 12700 E 19th Avenue, Aurora, CO 80045-2560, USA
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20
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Lacolley P, Regnault V, Segers P, Laurent S. Vascular Smooth Muscle Cells and Arterial Stiffening: Relevance in Development, Aging, and Disease. Physiol Rev 2017; 97:1555-1617. [DOI: 10.1152/physrev.00003.2017] [Citation(s) in RCA: 332] [Impact Index Per Article: 47.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 05/15/2017] [Accepted: 05/26/2017] [Indexed: 12/18/2022] Open
Abstract
The cushioning function of large arteries encompasses distension during systole and recoil during diastole which transforms pulsatile flow into a steady flow in the microcirculation. Arterial stiffness, the inverse of distensibility, has been implicated in various etiologies of chronic common and monogenic cardiovascular diseases and is a major cause of morbidity and mortality globally. The first components that contribute to arterial stiffening are extracellular matrix (ECM) proteins that support the mechanical load, while the second important components are vascular smooth muscle cells (VSMCs), which not only regulate actomyosin interactions for contraction but mediate also mechanotransduction in cell-ECM homeostasis. Eventually, VSMC plasticity and signaling in both conductance and resistance arteries are highly relevant to the physiology of normal and early vascular aging. This review summarizes current concepts of central pressure and tensile pulsatile circumferential stress as key mechanical determinants of arterial wall remodeling, cell-ECM interactions depending mainly on the architecture of cytoskeletal proteins and focal adhesion, the large/small arteries cross-talk that gives rise to target organ damage, and inflammatory pathways leading to calcification or atherosclerosis. We further speculate on the contribution of cellular stiffness along the arterial tree to vascular wall stiffness. In addition, this review provides the latest advances in the identification of gene variants affecting arterial stiffening. Now that important hemodynamic and molecular mechanisms of arterial stiffness have been elucidated, and the complex interplay between ECM, cells, and sensors identified, further research should study their potential to halt or to reverse the development of arterial stiffness.
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Affiliation(s)
- Patrick Lacolley
- INSERM, U1116, Vandœuvre-lès-Nancy, France; Université de Lorraine, Nancy, France; IBiTech-bioMMeda, Department of Electronics and Information Systems, Ghent University, Gent, Belgium; Department of Pharmacology, European Georges Pompidou Hospital, Assistance Publique Hôpitaux de Paris, France; PARCC INSERM, UMR 970, Paris, France; and University Paris Descartes, Paris, France
| | - Véronique Regnault
- INSERM, U1116, Vandœuvre-lès-Nancy, France; Université de Lorraine, Nancy, France; IBiTech-bioMMeda, Department of Electronics and Information Systems, Ghent University, Gent, Belgium; Department of Pharmacology, European Georges Pompidou Hospital, Assistance Publique Hôpitaux de Paris, France; PARCC INSERM, UMR 970, Paris, France; and University Paris Descartes, Paris, France
| | - Patrick Segers
- INSERM, U1116, Vandœuvre-lès-Nancy, France; Université de Lorraine, Nancy, France; IBiTech-bioMMeda, Department of Electronics and Information Systems, Ghent University, Gent, Belgium; Department of Pharmacology, European Georges Pompidou Hospital, Assistance Publique Hôpitaux de Paris, France; PARCC INSERM, UMR 970, Paris, France; and University Paris Descartes, Paris, France
| | - Stéphane Laurent
- INSERM, U1116, Vandœuvre-lès-Nancy, France; Université de Lorraine, Nancy, France; IBiTech-bioMMeda, Department of Electronics and Information Systems, Ghent University, Gent, Belgium; Department of Pharmacology, European Georges Pompidou Hospital, Assistance Publique Hôpitaux de Paris, France; PARCC INSERM, UMR 970, Paris, France; and University Paris Descartes, Paris, France
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21
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Hays BS, Baker M, Laib A, Tan W, Udholm S, Goldstein BH, Sanders SP, Opotowsky AR, Veldtman GR. Histopathological abnormalities in the central arteries and veins of Fontan subjects. Heart 2017; 104:324-331. [PMID: 28970278 DOI: 10.1136/heartjnl-2017-311838] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/07/2017] [Accepted: 07/23/2017] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE Fontan circulations have obligatory venous hypertension, depressed cardiac output and abnormal arterial elastance. Ventriculovascular coupling is known to be abnormal, but the underlying mechanisms are poorly defined. We aim to describe the histopathological features of vascular remodelling encountered in the central arteries and veins in the Fontan circulation as a possible underlying pathological representation of abnormal ventriculovascular coupling. METHODS Postmortemvasculature (inferior vena cava (IVC), superior vena cava (SVC), pulmonary artery (PA), pulmonary vein (PV) and aorta) of 13 patients with a Fontan circulation (mean age 29.9 years, range 9.0-59.8 years) and 2 biventricular controls (ages 17.9 and 30.2 years) was examined. RESULTS IVC and SVC: Eccentric and variable intimal fibromuscular proliferation occurred in 11 Fontan subjects. There was variable loss of medial smooth muscle bundles with reciprocal replacement with dense collagenous tissue.PA: Similar intimal fibromuscular proliferation was seen; however, these intimal changes were accompanied by medial thinning rather than expansion, medial myxoid degeneration and elastic alteration.PV: The PVs demonstrated intimal fibroproliferation and disorganisation of the muscular media.Aorta: The aortic lamina intima was thickened, with associated fibromuscular proliferation and elasticisation. There was also moderate lymphocytic inflammation in the aortic wall. CONCLUSIONS Vascular architectural remodelling is common in Fontan patients. The central veins demonstrate profound changes of eccentric intimal expansion and smooth muscle replacement with collagen. The pulmonary demonstrated abnormal intimal proliferation, and aortic remodelling was characterised by intima lamina thickening and a moderate degree of aortic wall inflammation.
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Affiliation(s)
- Brandon S Hays
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Cardiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Michael Baker
- Cardiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Division of Pathology, Cincinnati Children's Hospital Medical Centre, Cincinnati, Ohio, USA
| | - Annie Laib
- Cardiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Division of Pathology, Cincinnati Children's Hospital Medical Centre, Cincinnati, Ohio, USA
| | - Wei Tan
- University of Colorado at Boulder, Boulder, Colorado, USA
| | - Sebastian Udholm
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Bryan H Goldstein
- Heart Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA.,Cardiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | | | | | - Gruschen R Veldtman
- Adolescent and Adult Congenital Heart Disease Program, Cincinnati Children's Hospital Medical Centre, Ohio, Cincinnati, USA
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22
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Dieffenbach PB, Haeger CM, Coronata AMF, Choi KM, Varelas X, Tschumperlin DJ, Fredenburgh LE. Arterial stiffness induces remodeling phenotypes in pulmonary artery smooth muscle cells via YAP/TAZ-mediated repression of cyclooxygenase-2. Am J Physiol Lung Cell Mol Physiol 2017; 313:L628-L647. [PMID: 28642262 PMCID: PMC5625262 DOI: 10.1152/ajplung.00173.2017] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 06/07/2017] [Accepted: 06/11/2017] [Indexed: 12/20/2022] Open
Abstract
Pulmonary arterial stiffness is an independent risk factor for mortality in pulmonary hypertension (PH) and plays a critical role in PH pathophysiology. Our laboratory has recently demonstrated arterial stiffening early in experimental PH, along with evidence for a mechanobiological feedback loop by which arterial stiffening promotes further cellular remodeling behaviors (Liu F, Haeger CM, Dieffenbach PB, Sicard D, Chrobak I, Coronata AM, Suárez Velandia MM, Vitali S, Colas RA, Norris PC, Marinković A, Liu X, Ma J, Rose CD, Lee SJ, Comhair SA, Erzurum SC, McDonald JD, Serhan CN, Walsh SR, Tschumperlin DJ, Fredenburgh LE. JCI Insight 1: e86987, 2016). Cyclooxygenase-2 (COX-2) and prostaglandin signaling have been implicated in stiffness-mediated regulation, with prostaglandin activity inversely correlated to matrix stiffness and remodeling behaviors in vitro, as well as to disease progression in rodent PH models. The mechanism by which mechanical signaling translates to reduced COX-2 activity in pulmonary vascular cells is unknown. The present work investigated the transcriptional regulators Yes-associated protein (YAP) and WW domain-containing transcription regulator 1 (WWTR1, a.k.a., TAZ), which are known drivers of downstream mechanical signaling, in mediating stiffness-induced changes in COX-2 and prostaglandin activity in pulmonary artery smooth muscle cells (PASMCs). We found that YAP/TAZ activity is increased in PAH PASMCs and experimental PH and is necessary for the development of stiffness-dependent remodeling phenotypes. Knockdown of YAP and TAZ markedly induces COX-2 expression and downstream prostaglandin production by approximately threefold, whereas overexpression of YAP or TAZ reduces COX-2 expression and prostaglandin production to near undetectable levels. Together, our findings demonstrate a stiffness-dependent YAP/TAZ-mediated positive feedback loop that drives remodeling phenotypes in PASMCs via reduced COX-2 and prostaglandin activity. The ability to interrupt this critical mechanobiological feedback loop and enhance local prostaglandin activity via manipulation of YAP/TAZ signaling presents a highly attractive novel strategy for the treatment of PH.
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Affiliation(s)
- Paul B Dieffenbach
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts
| | - Christina Mallarino Haeger
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts
| | - Anna Maria F Coronata
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts
| | - Kyoung Moo Choi
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; and
| | - Xaralabos Varelas
- Department of Biochemistry, Boston University School of Medicine, Boston, Massachusetts
| | - Daniel J Tschumperlin
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; and
| | - Laura E Fredenburgh
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts;
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Experimental Evidences Supporting Training-Induced Benefits in Spontaneously Hypertensive Rats. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 999:287-306. [DOI: 10.1007/978-981-10-4307-9_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abstract
The normal pulmonary circulation is a low-pressure, high-compliance system. Pulmonary arterial compliance decreases in the presence of pulmonary hypertension because of increased extracellular matrix/collagen deposition in the pulmonary arteries. Loss of pulmonary arterial compliance has been consistently shown to be a predictor of increased mortality in patients with pulmonary hypertension, even more so than pulmonary vascular resistance in some studies. Decreased pulmonary arterial compliance causes premature reflection of waves from the distal pulmonary vasculature, leading to increased pulsatile right ventricular afterload and eventually right ventricular failure. Evidence suggests that decreased pulmonary arterial compliance is a cause rather than a consequence of distal small vessel proliferative vasculopathy. Pulmonary arterial compliance decreases early in the disease process even when pulmonary artery pressure and pulmonary vascular resistance are normal, potentially enabling early diagnosis of pulmonary vascular disease, especially in high-risk populations. With the recognition of the prognostic importance of pulmonary arterial compliance, its impact on right ventricular function, and its contributory role in the development and progression of distal small-vessel proliferative vasculopathy, pulmonary arterial compliance is an attractive target for the treatment of pulmonary hypertension.
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Weir-McCall JR, Kamalasanan A, Cassidy DB, Struthers AD, Lipworth BJ, Houston JG. Assessment of proximal pulmonary arterial stiffness using magnetic resonance imaging: effects of technique, age and exercise. BMJ Open Respir Res 2016; 3:e000149. [PMID: 27843548 PMCID: PMC5073626 DOI: 10.1136/bmjresp-2016-000149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2016] [Revised: 09/16/2016] [Accepted: 09/19/2016] [Indexed: 01/09/2023] Open
Abstract
Introduction To compare the reproducibility of pulmonary pulse wave velocity (PWV) techniques, and the effects of age and exercise on these. Methods 10 young healthy volunteers (YHV) and 20 older healthy volunteers (OHV) with no cardiac or lung condition were recruited. High temporal resolution phase contrast sequences were performed through the main pulmonary arteries (MPAs), right pulmonary arteries (RPAs) and left pulmonary arteries (LPAs), while high spatial resolution sequences were obtained through the MPA. YHV underwent 2 MRIs 6 months apart with the sequences repeated during exercise. OHV underwent an MRI scan with on-table repetition. PWV was calculated using the transit time (TT) and flow area techniques (QA). 3 methods for calculating QA PWV were compared. Results PWV did not differ between the two age groups (YHV 2.4±0.3/ms, OHV 2.9±0.2/ms, p=0.1). Using a high temporal resolution sequence through the RPA using the QA accounting for wave reflections yielded consistently better within-scan, interscan, intraobserver and interobserver reproducibility. Exercise did not result in a change in either TT PWV (mean (95% CI) of the differences: −0.42 (−1.2 to 0.4), p=0.24) or QA PWV (mean (95% CI) of the differences: 0.10 (−0.5 to 0.9), p=0.49) despite a significant rise in heart rate (65±2 to 87±3, p<0.0001), blood pressure (113/68 to 130/84, p<0.0001) and cardiac output (5.4±0.4 to 6.7±0.6 L/min, p=0.004). Conclusions QA PWV performed through the RPA using a high temporal resolution sequence accounting for wave reflections yields the most reproducible measurements of pulmonary PWV.
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Affiliation(s)
- Jonathan R Weir-McCall
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
| | - Anu Kamalasanan
- Department of Clinical Radiology , Ninewells Hospital and Medical School , Dundee , UK
| | - Deidre B Cassidy
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
| | - Allan D Struthers
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
| | - Brian J Lipworth
- Scottish Centre for Respiratory Research, Medical Research Institute, University of Dundee , Dundee , UK
| | - J Graeme Houston
- Division of Cardiovascular and Diabetes Medicine , Medical Research Institute, University of Dundee , Dundee , UK
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Pulmonary Arterial Stiffness: Toward a New Paradigm in Pulmonary Arterial Hypertension Pathophysiology and Assessment. Curr Hypertens Rep 2016; 18:4. [PMID: 26733189 DOI: 10.1007/s11906-015-0609-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Stiffening of the pulmonary arterial bed with the subsequent increased load on the right ventricle is a paramount feature of pulmonary hypertension (PH). The pathophysiology of vascular stiffening is a complex and self-reinforcing function of extracellular matrix remodeling, driven by recruitment of circulating inflammatory cells and their interactions with resident vascular cells, and mechanotransduction of altered hemodynamic forces throughout the ventricular-vascular axis. New approaches to understanding the cell and molecular determinants of the pathophysiology combine novel biopolymer substrates, controlled flow conditions, and defined cell types to recapitulate the biomechanical environment in vitro. Simultaneously, advances are occurring to assess novel parameters of stiffness in vivo. In this comprehensive state-of-art review, we describe clinical hemodynamic markers, together with the newest translational echocardiographic and cardiac magnetic resonance imaging methods, to assess vascular stiffness and ventricular-vascular coupling. Finally, fluid-tissue interactions appear to offer a novel route of investigating the mechanotransduction processes and disease progression.
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Al-Naamani N, Preston IR, Paulus JK, Hill NS, Roberts KE. Pulmonary Arterial Capacitance Is an Important Predictor of Mortality in Heart Failure With a Preserved Ejection Fraction. JACC-HEART FAILURE 2016; 3:467-474. [PMID: 26046840 DOI: 10.1016/j.jchf.2015.01.013] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Accepted: 01/09/2015] [Indexed: 12/31/2022]
Abstract
OBJECTIVES The purpose of this study was to determine the predictors of mortality in patients with pulmonary hypertension (PH) associated with heart failure with preserved ejection fraction (HFpEF). BACKGROUND PH is commonly associated with HFpEF. The predictors of mortality for patients with these conditions are not well characterized. METHODS In a prospective cohort of patients with right heart catheterization, we identified 73 adult patients who had pulmonary hypertension due to left heart disease (PH-LHD) associated with HFpEF (left ventricular ejection fraction ≥50% by echocardiography); hemodynamically defined as a mean pulmonary artery pressure ≥25 mm Hg and pulmonary artery wedge pressure >15 mm Hg. PH severity was classified according to the diastolic pressure gradient (DPG). Cox proportional hazards ratios were used to estimate the associations between clinical variables and mortality. Receiver-operating characteristic curves were used to evaluate the ability of hemodynamic measurements to predict mortality. RESULTS The mean age for study subjects was 69 ± 12 years and 74% were female. Patients classified as having combined post-capillary PH and pre-capillary PH (DPG ≥7) were not at increased risk of death as compared to patients with isolated post-capillary PH (DPG <7). A baseline pulmonary arterial capacitance (PAC) of <1.1 ml/mm Hg was 91% sensitive in predicting mortality, with better discriminatory ability than DPG, transpulmonary gradient, or pulmonary vascular resistance (area under the curve of 0.73, 0.50, 0.45, and 0.37, respectively). Fifty-seven subjects underwent acute vasoreactivity testing with inhaled nitric oxide. Acute vasodilator response by the Rich or Sitbon criteria was not associated with improved survival. CONCLUSIONS PAC is the best predictor of mortality in our cohort and may be useful in describing phenotypic subgroups among those with PH-LHD associated with HFpEF. Acute vasodilator testing did not predict outcome in our cohort but needs to be further investigated.
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Affiliation(s)
| | - Ioana R Preston
- Department of Medicine, Tufts Medical Center, Boston, Massachusetts
| | - Jessica K Paulus
- Tufts Clinical and Translational Science Institute, Boston, Massachusetts
| | - Nicholas S Hill
- Department of Medicine, Tufts Medical Center, Boston, Massachusetts
| | - Kari E Roberts
- Department of Medicine, Tufts Medical Center, Boston, Massachusetts.
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Elliott W, Scott-Drechsel D, Tan W. In Vitro Model of Physiological and Pathological Blood Flow with Application to Investigations of Vascular Cell Remodeling. J Vis Exp 2015:e53224. [PMID: 26554396 DOI: 10.3791/53224] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Vascular disease is a common cause of death within the United States. Herein, we present a method to examine the contribution of flow dynamics towards vascular disease pathologies. Unhealthy arteries often present with wall stiffening, scarring, or partial stenosis which may all affect fluid flow rates, and the magnitude of pulsatile flow, or pulsatility index. Replication of various flow conditions is the result of tuning a flow pressure damping chamber downstream of a blood pump. Introduction of air within a closed flow system allows for a compressible medium to absorb pulsatile pressure from the pump, and therefore vary the pulsatility index. The method described herein is simply reproduced, with highly controllable input, and easily measurable results. Some limitations are recreation of the complex physiological pulse waveform, which is only approximated by the system. Endothelial cells, smooth muscle cells, and fibroblasts are affected by the blood flow through the artery. The dynamic component of blood flow is determined by the cardiac output and arterial wall compliance. Vascular cell mechano-transduction of flow dynamics may trigger cytokine release and cross-talk between cell types within the artery. Co-culture of vascular cells is a more accurate picture reflecting cell-cell interaction on the blood vessel wall and vascular response to mechanical signaling. Contribution of flow dynamics, including the cell response to the dynamic and mean (or steady) components of flow, is therefore an important metric in determining disease pathology and treatment efficacy. Through introducing an in vitro co-culture model and pressure damping downstream of blood pump which produces simulated cardiac output, various arterial disease pathologies may be investigated.
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Affiliation(s)
- Winston Elliott
- Department of Mechanical Engineering, University of Colorado at Boulder;
| | | | - Wei Tan
- Department of Mechanical Engineering, University of Colorado at Boulder
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29
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Breitling S, Ravindran K, Goldenberg NM, Kuebler WM. The pathophysiology of pulmonary hypertension in left heart disease. Am J Physiol Lung Cell Mol Physiol 2015; 309:L924-41. [DOI: 10.1152/ajplung.00146.2015] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2015] [Accepted: 08/20/2015] [Indexed: 12/17/2022] Open
Abstract
Pulmonary hypertension (PH) is characterized by elevated pulmonary arterial pressure leading to right-sided heart failure and can arise from a wide range of etiologies. The most common cause of PH, termed Group 2 PH, is left-sided heart failure and is commonly known as pulmonary hypertension with left heart disease (PH-LHD). Importantly, while sharing many clinical features with pulmonary arterial hypertension (PAH), PH-LHD differs significantly at the cellular and physiological levels. These fundamental pathophysiological differences largely account for the poor response to PAH therapies experienced by PH-LHD patients. The relatively high prevalence of this disease, coupled with its unique features compared with PAH, signal the importance of an in-depth understanding of the mechanistic details of PH-LHD. The present review will focus on the current state of knowledge regarding the pathomechanisms of PH-LHD, highlighting work carried out both in human trials and in preclinical animal models. Adaptive processes at the alveolocapillary barrier and in the pulmonary circulation, including alterations in alveolar fluid transport, endothelial junctional integrity, and vasoactive mediator secretion will be discussed in detail, highlighting the aspects that impact the response to, and development of, novel therapeutics.
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Affiliation(s)
- Siegfried Breitling
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario, Canada
- Institute for Chemistry and Biochemistry, Freie Universität Berlin, Germany
| | - Krishnan Ravindran
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Neil M. Goldenberg
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario, Canada
- Department of Anesthesia, University of Toronto, Toronto, Ontario, Canada
| | - Wolfgang M. Kuebler
- Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario, Canada
- Institute of Physiology, Charité-Universitätsmedizin Berlin, Germany
- Departments of Surgery and Physiology, University of Toronto, Toronto, Ontario, Canada; and
- German Heart Institute Berlin, Berlin, Germany
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Liu A, Tian L, Golob M, Eickhoff JC, Boston M, Chesler NC. 17β-Estradiol Attenuates Conduit Pulmonary Artery Mechanical Property Changes With Pulmonary Arterial Hypertension. Hypertension 2015; 66:1082-8. [PMID: 26418020 DOI: 10.1161/hypertensionaha.115.05843] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2015] [Accepted: 08/27/2015] [Indexed: 01/23/2023]
Abstract
Pulmonary arterial hypertension (PAH), a rapidly fatal vascular disease, strikes women more often than men. Paradoxically, female PAH patients have better prognosis and survival rates than males. The female sex hormone 17β-estradiol has been linked to the better outcome of PAH in females; however, the mechanisms by which 17β-estradiol alters PAH progression and outcomes remain unclear. Because proximal pulmonary arterial (PA) stiffness, one hallmark of PAH, is a powerful predictor of mortality and morbidity, we hypothesized that 17β-estradiol attenuates PAH-induced changes in mechanical properties in conduit proximal PAs, which imparts hemodynamic and energetic benefits to right ventricular function. To test this hypothesis, female mice were ovariectomized and treated with 17β-estradiol or placebo. PAH was induced in mice using SU5416 and chronic hypoxia. Extra-lobar left PAs were isolated and mechanically tested ex vivo to study both static and frequency-dependent mechanical behaviors in the presence or absence of smooth muscle cell activation. Our static mechanical test showed significant stiffening of large PAs with PAH (P<0.05). 17β-Estradiol restored PA compliance to control levels. The dynamic mechanical test demonstrated that 17β-estradiol protected the arterial wall from the PAH-induced frequency-dependent decline in dynamic stiffness and loss of viscosity with PAH (P<0.05). As demonstrated by the in vivo measurement of PA hemodynamics via right ventricular catheterization, modulation by 17β-estradiol of mechanical proximal PAs reduced pulsatile loading, which contributed to improved ventricular-vascular coupling. This study provides a mechanical mechanism for delayed disease progression and better outcome in female PAH patients and underscores the therapeutic potential of 17β-estradiol in PAH.
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Affiliation(s)
- Aiping Liu
- From the Departments of Biomedical Engineering, (A.L., L.T., M.G., M.B., N.C.C.) and Biostatistics and Medical Informatics (J.C.E.), University of Wisconsin-Madison
| | - Lian Tian
- From the Departments of Biomedical Engineering, (A.L., L.T., M.G., M.B., N.C.C.) and Biostatistics and Medical Informatics (J.C.E.), University of Wisconsin-Madison
| | - Mark Golob
- From the Departments of Biomedical Engineering, (A.L., L.T., M.G., M.B., N.C.C.) and Biostatistics and Medical Informatics (J.C.E.), University of Wisconsin-Madison
| | - Jens C Eickhoff
- From the Departments of Biomedical Engineering, (A.L., L.T., M.G., M.B., N.C.C.) and Biostatistics and Medical Informatics (J.C.E.), University of Wisconsin-Madison
| | - Madison Boston
- From the Departments of Biomedical Engineering, (A.L., L.T., M.G., M.B., N.C.C.) and Biostatistics and Medical Informatics (J.C.E.), University of Wisconsin-Madison
| | - Naomi C Chesler
- From the Departments of Biomedical Engineering, (A.L., L.T., M.G., M.B., N.C.C.) and Biostatistics and Medical Informatics (J.C.E.), University of Wisconsin-Madison.
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Prakash YS, Tschumperlin DJ, Stenmark KR. Coming to terms with tissue engineering and regenerative medicine in the lung. Am J Physiol Lung Cell Mol Physiol 2015; 309:L625-38. [PMID: 26254424 DOI: 10.1152/ajplung.00204.2015] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 08/04/2015] [Indexed: 01/10/2023] Open
Abstract
Lung diseases such as emphysema, interstitial fibrosis, and pulmonary vascular diseases cause significant morbidity and mortality, but despite substantial mechanistic understanding, clinical management options for them are limited, with lung transplantation being implemented at end stages. However, limited donor lung availability, graft rejection, and long-term problems after transplantation are major hurdles to lung transplantation being a panacea. Bioengineering the lung is an exciting and emerging solution that has the ultimate aim of generating lung tissues and organs for transplantation. In this article we capture and review the current state of the art in lung bioengineering, from the multimodal approaches, to creating anatomically appropriate lung scaffolds that can be recellularized to eventually yield functioning, transplant-ready lungs. Strategies for decellularizing mammalian lungs to create scaffolds with native extracellular matrix components vs. de novo generation of scaffolds using biocompatible materials are discussed. Strengths vs. limitations of recellularization using different cell types of various pluripotency such as embryonic, mesenchymal, and induced pluripotent stem cells are highlighted. Current hurdles to guide future research toward achieving the clinical goal of transplantation of a bioengineered lung are discussed.
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Affiliation(s)
- Y S Prakash
- Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota; Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota;
| | - Daniel J Tschumperlin
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota; Division of Pulmonary Medicine, Mayo Clinic, Rochester, Minnesota; and
| | - Kurt R Stenmark
- Department of Pediatrics, University of Colorado, Aurora, Colorado
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Kheyfets VO, Rios L, Smith T, Schroeder T, Mueller J, Murali S, Lasorda D, Zikos A, Spotti J, Reilly JJ, Finol EA. Patient-specific computational modeling of blood flow in the pulmonary arterial circulation. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2015; 120:88-101. [PMID: 25975872 PMCID: PMC4441565 DOI: 10.1016/j.cmpb.2015.04.005] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 03/15/2015] [Accepted: 04/14/2015] [Indexed: 06/04/2023]
Abstract
Computational fluid dynamics (CFD) modeling of the pulmonary vasculature has the potential to reveal continuum metrics associated with the hemodynamic stress acting on the vascular endothelium. It is widely accepted that the endothelium responds to flow-induced stress by releasing vasoactive substances that can dilate and constrict blood vessels locally. The objectives of this study are to examine the extent of patient specificity required to obtain a significant association of CFD output metrics and clinical measures in models of the pulmonary arterial circulation, and to evaluate the potential correlation of wall shear stress (WSS) with established metrics indicative of right ventricular (RV) afterload in pulmonary hypertension (PH). Right Heart Catheterization (RHC) hemodynamic data and contrast-enhanced computed tomography (CT) imaging were retrospectively acquired for 10 PH patients and processed to simulate blood flow in the pulmonary arteries. While conducting CFD modeling of the reconstructed patient-specific vasculatures, we experimented with three different outflow boundary conditions to investigate the potential for using computationally derived spatially averaged wall shear stress (SAWSS) as a metric of RV afterload. SAWSS was correlated with both pulmonary vascular resistance (PVR) (R(2)=0.77, P<0.05) and arterial compliance (C) (R(2)=0.63, P<0.05), but the extent of the correlation was affected by the degree of patient specificity incorporated in the fluid flow boundary conditions. We found that decreasing the distal PVR alters the flow distribution and changes the local velocity profile in the distal vessels, thereby increasing the local WSS. Nevertheless, implementing generic outflow boundary conditions still resulted in statistically significant SAWSS correlations with respect to both metrics of RV afterload, suggesting that the CFD model could be executed without the need for complex outflow boundary conditions that require invasively obtained patient-specific data. A preliminary study investigating the relationship between outlet diameter and flow distribution in the pulmonary tree offers a potential computationally inexpensive alternative to pressure based outflow boundary conditions.
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Affiliation(s)
- Vitaly O Kheyfets
- Department of Bioengineering, UC Denver - Anschutz Medical Campus, Children's Hospital Colorado, 13123 E. 16th Ave B100, Aurora, CO 80045, United States.
| | - Lourdes Rios
- The University of Texas at San Antonio, Department of Biomedical Engineering, San Antonio, TX 78249, United States; The University of Texas at San Antonio, Department of Biological Sciences, San Antonio, TX 78249, United States.
| | - Triston Smith
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - Theodore Schroeder
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - Jeffrey Mueller
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - Srinivas Murali
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - David Lasorda
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - Anthony Zikos
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - Jennifer Spotti
- Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Radiology, Pittsburgh, PA 15212, United States; Western Pennsylvania Allegheny Health System, Allegheny General Hospital, McGinnis Cardiovascular Institute, Department of Cardiology, Pittsburgh, PA 15212, United States.
| | - John J Reilly
- University of Pittsburgh, Department of Medicine, Pittsburgh, PA 15261, United States.
| | - Ender A Finol
- The University of Texas at San Antonio, Department of Biomedical Engineering, San Antonio, TX 78249, United States.
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Weir-McCall JR, Struthers AD, Lipworth BJ, Houston JG. The role of pulmonary arterial stiffness in COPD. Respir Med 2015; 109:1381-90. [PMID: 26095859 PMCID: PMC4646836 DOI: 10.1016/j.rmed.2015.06.005] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Revised: 05/10/2015] [Accepted: 06/10/2015] [Indexed: 12/23/2022]
Abstract
COPD is the second most common cause of pulmonary hypertension, and is a common complication of severe COPD with significant implications for both quality of life and mortality. However, the use of a rigid diagnostic threshold of a mean pulmonary arterial pressure (mPAP) of ≥25mHg when considering the impact of the pulmonary vasculature on symptoms and disease is misleading. Even minimal exertion causes oxygen desaturation and elevations in mPAP, with right ventricular hypertrophy and dilatation present in patients with mild to moderate COPD with pressures below the threshold for diagnosis of pulmonary hypertension. This has significant implications, with right ventricular dysfunction associated with poorer exercise capability and increased mortality independent of pulmonary function tests. The compliance of the pulmonary artery (PA) is a key component in decoupling the right ventricle from the pulmonary bed, allowing the right ventricle to work at maximum efficiency and protecting the microcirculation from large pressure gradients. PA stiffness increases with the severity of COPD, and correlates well with the presence of exercise induced pulmonary hypertension. A curvilinear relationship exists between PA distensibility and mPAP and pulmonary vascular resistance (PVR) with marked loss of distensibility before a rapid rise in mPAP and PVR occurs with resultant right ventricular failure. This combination of features suggests PA stiffness as a promising biomarker for early detection of pulmonary vascular disease, and to play a role in right ventricular failure in COPD. Early detection would open this up as a potential therapeutic target before end stage arterial remodelling occurs. Pulmonary hypertension is common in COPD. Right ventricular remodeling occurs at pressures below the diagnostic threshold of PH. Pulmonary arterial stiffening occurs early in the development of PH. Non-invasive measurement of pulmonary stiffness may serve as an early biomarker of PH.
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Affiliation(s)
- Jonathan R Weir-McCall
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, United Kingdom.
| | - Allan D Struthers
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, United Kingdom
| | - Brian J Lipworth
- Scottish Centre for Respiratory Research, Medical Research Institute, University of Dundee, Dundee, United Kingdom
| | - J Graeme Houston
- Division of Cardiovascular and Diabetes Medicine, Medical Research Institute, University of Dundee, Dundee, United Kingdom
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Kheyfets V, Thirugnanasambandam M, Rios L, Evans D, Smith T, Schroeder T, Mueller J, Murali S, Lasorda D, Spotti J, Finol E. The role of wall shear stress in the assessment of right ventricle hydraulic workload. Pulm Circ 2015; 5:90-100. [PMID: 25992274 DOI: 10.1086/679703] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 07/22/2014] [Indexed: 11/03/2022] Open
Abstract
Pulmonary hypertension (PH) is a devastating disease affecting approximately 15-50 people per million, with a higher incidence in women. PH mortality is mostly attributed to right ventricle (RV) failure, which results from RV hypotrophy due to an overburdened hydraulic workload. The objective of this study is to correlate wall shear stress (WSS) with hemodynamic metrics that are generally accepted as clinical indicators of RV workload and are well correlated with disease outcome. Retrospective right heart catheterization data for 20 PH patients were analyzed to derive pulmonary vascular resistance (PVR), arterial compliance (C), and an index of wave reflections (Γ). Patient-specific contrast-enhanced computed tomography chest images were used to reconstruct the individual pulmonary arterial trees up to the seventh generation. Computational fluid dynamics analyses simulating blood flow at peak systole were conducted for each vascular model to calculate WSS distributions on the endothelial surface of the pulmonary arteries. WSS was found to be decreased proportionally with elevated PVR and reduced C. Spatially averaged WSS (SAWSS) was positively correlated with PVR (R (2) = 0.66), C (R (2) = 0.73), and Γ (R (2) = 0.5) and also showed promising preliminary correlations with RV geometric characteristics. Evaluating WSS at random cross sections in the proximal vasculature (main, right, and left pulmonary arteries), the type of data that can be acquired from phase-contrast magnetic resonance imaging, did not reveal the same correlations. In conclusion, we found that WSS has the potential to be a viable and clinically useful noninvasive metric of PH disease progression and RV health. Future work should be focused on evaluating whether SAWSS has prognostic value in the management of PH and whether it can be used as a rapid reactivity assessment tool, which would aid in selection of appropriate therapies.
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Affiliation(s)
- Vitaly Kheyfets
- Department of Biomedical Engineering, University of Texas, San Antonio, Texas, USA
| | | | - Lourdes Rios
- Department of Biological Sciences, University of Texas, San Antonio, Texas, USA
| | - Daniel Evans
- Department of Mechanical Engineering, University of Texas, San Antonio, Texas, USA
| | - Triston Smith
- Department of Cardiology, McGinnis Cardiovascular Institute, Allegheny General Hospital, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Theodore Schroeder
- Department of Radiology, McGinnis Cardiovascular Institute, Allegheny General Hospital, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Jeffrey Mueller
- Department of Radiology, McGinnis Cardiovascular Institute, Allegheny General Hospital, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Srinivas Murali
- Department of Cardiology, McGinnis Cardiovascular Institute, Allegheny General Hospital, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - David Lasorda
- Department of Cardiology, McGinnis Cardiovascular Institute, Allegheny General Hospital, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Jennifer Spotti
- Department of Cardiology, McGinnis Cardiovascular Institute, Allegheny General Hospital, Allegheny Health Network, Pittsburgh, Pennsylvania, USA
| | - Ender Finol
- Department of Biomedical Engineering, University of Texas, San Antonio, Texas, USA
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Calcitonin gene-related peptide (CGRP) receptors are important to maintain cerebrovascular reactivity in chronic hypertension. PLoS One 2015; 10:e0123697. [PMID: 25860809 PMCID: PMC4393086 DOI: 10.1371/journal.pone.0123697] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 03/06/2015] [Indexed: 11/21/2022] Open
Abstract
Cerebral blood flow autoregulation (CA) shifts to higher blood pressures in chronic hypertensive patients, which increases their risk for brain damage. Although cerebral vascular smooth muscle cells express the potent vasodilatatory peptides calcitonin gene-related peptide (CGRP) and adrenomedullin (AM) and their receptors (calcitonin receptor-like receptor (Calclr), receptor-modifying proteins (RAMP) 1 and 2), their contribution to CA during chronic hypertension is poorly understood. Here we report that chronic (10 weeks) hypertensive (one-kidney-one-clip-method) mice overexpressing the Calclr in smooth muscle cells (CLR-tg), which increases the natural sensitivity of the brain vasculature to CGRP and AM show significantly better blood pressure drop-induced cerebrovascular reactivity than wt controls. Compared to sham mice, this was paralleled by increased cerebral CGRP-binding sites (receptor autoradiography), significantly in CLR-tg but not wt mice. AM-binding sites remained unchanged. Whereas hypertension did not alter RAMP-1 expression (droplet digital (dd) PCR) in either mouse line, RAMP-2 expression dropped significantly in both mouse lines by about 65%. Moreover, in wt only Calclr expression was reduced by about 70% parallel to an increase of smooth muscle actin (Acta2) expression. Thus, chronic hypertension induces a stoichiometric shift between CGRP and AM receptors in favor of the CGRP receptor. However, the parallel reduction of Calclr expression observed in wt mice but not CLR-tg mice appears to be a key mechanism in chronic hypertension impairing cerebrovascular reactivity.
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36
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Elliott WH, Tan Y, Li M, Tan W. RETRACTED ARTICLE: High Pulsatility Flow Promotes Vascular Fibrosis by Triggering Endothelial EndMT and Fibroblast Activation. Cell Mol Bioeng 2015; 8:285-295. [PMID: 34522234 DOI: 10.1007/s12195-015-0386-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 03/16/2015] [Indexed: 11/29/2022] Open
Abstract
Vascular fibrosis, the formation of excess fibrous tissue on the blood vessel wall, is characterized by unmitigated proliferation of fibroblasts or myofibroblast-like cells exhibiting α-smooth-muscle-actin in vessel lumen and other vascular layers. It likely contributes to vascular unresponsiveness to conventional therapies. This paper demonstrates a new flow-induced vascular fibrosis mechanism. Using our developed flow system which simulates the effect of vessel stiffening and generates unidirectional high pulsatility flow (HPF) with the mean shear flow at a physiological level, we have shown that HPF caused vascular endothelial dysfunction. Herein, we further explored the role of HPF in vascular fibrosis through endothelial-to-mesenchymal transdifferentiation (EndMT). Pulmonary arterial endothelial cells (ECs) were exposed to steady flow and HPF, which have the same physiological mean fluid shear but different in flow pulsatility. Cells were analyzed after being conditioned with flows for 24 or 48 h. HPF was found to induce EndMT of cells after 48 h stimulation; cells demonstrated drastically decreased expression in EC marker CD31, as well as increased transforming growth factor β, α-SMA, and collagen type-I, in both gene and protein expression profiles. Using the flow media from HPF-conditioned endothelial culture to cultivate arterial adventitial fibroblasts (AdvFBs) and ECs respectively, we found that the conditioned media respectively enhanced migration, proliferation and α-SMA expression of AdvFBs, and induced EndMT of ECs. It was further revealed that cells exposed to HPF exhibited much higher percentage of caspase-positive cells compared to those exposed to steady flow. Apoptotic cells together with remaining, caspase-negative cells suggested the presence of apoptosis-resistant dysfunctional ECs which likely underwent EndMT process and perpetuated fibrosis throughout vascular tissues. Therefore, our results indicate that prolonged HPF stimuli induce vascular fibrosis through triggering EndMT and EC-mediated AdvFB activation and migration, which follows initial endothelial inflammation, dysfunction and apoptosis.
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Affiliation(s)
- Winston H Elliott
- Department of Mechanical Engineering, University of Colorado at Boulder, 1111 Engineering Dr, ECME 114, Boulder, CO 80309-0427 USA
| | - Yan Tan
- Department of Mechanical Engineering, University of Colorado at Boulder, 1111 Engineering Dr, ECME 114, Boulder, CO 80309-0427 USA
| | - Min Li
- Department of Pediatrics, University of Colorado at Denver, Aurora, CO 80045 USA
| | - Wei Tan
- Department of Mechanical Engineering, University of Colorado at Boulder, 1111 Engineering Dr, ECME 114, Boulder, CO 80309-0427 USA.,Department of Pediatrics, University of Colorado at Denver, Aurora, CO 80045 USA
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Bloodworth NC, West JD, Merryman WD. Microvessel mechanobiology in pulmonary arterial hypertension: cause and effect. Hypertension 2015; 65:483-9. [PMID: 25534705 PMCID: PMC4326545 DOI: 10.1161/hypertensionaha.114.04652] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Nathaniel C Bloodworth
- From the Departments of Biomedical Engineering (N.C.B., W.D.M.) and Pulmonary and Critical Care Medicine (J.D.W.), Vanderbilt University, Nashville, TN
| | - James D West
- From the Departments of Biomedical Engineering (N.C.B., W.D.M.) and Pulmonary and Critical Care Medicine (J.D.W.), Vanderbilt University, Nashville, TN
| | - W David Merryman
- From the Departments of Biomedical Engineering (N.C.B., W.D.M.) and Pulmonary and Critical Care Medicine (J.D.W.), Vanderbilt University, Nashville, TN.
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38
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Boulate D, Perros F, Dorfmuller P, Arthur-Ataam J, Guihaire J, Lamrani L, Decante B, Humbert M, Eddahibi S, Dartevelle P, Fadel E, Mercier O. Pulmonary microvascular lesions regress in reperfused chronic thromboembolic pulmonary hypertension. J Heart Lung Transplant 2015; 34:457-67. [DOI: 10.1016/j.healun.2014.07.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 05/08/2014] [Accepted: 07/10/2014] [Indexed: 10/25/2022] Open
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Tan W, Madhavan K, Hunter KS, Park D, Stenmark KR. Vascular stiffening in pulmonary hypertension: cause or consequence? (2013 Grover Conference series). Pulm Circ 2014; 4:560-80. [PMID: 25610594 PMCID: PMC4278618 DOI: 10.1086/677370] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 05/27/2014] [Indexed: 12/24/2022] Open
Abstract
Recent studies have indicated that systemic arterial stiffening is a precursor to hypertension and that hypertension, in turn, can perpetuate arterial stiffening. Pulmonary artery (PA) stiffening is also well documented to occur in pulmonary hypertension (PH), and there is evidence that pulmonary vascular stiffness (PVS) may be a better predictor of outcome than pulmonary vascular resistance (PVR). We have hypothesized that the decreased flow-damping function of elastic PAs in PH likely initiates and/or perpetuates dysfunction of pulmonary microvasculature. Recent studies have shown that large-vessel stiffening increases flow pulsatility in the distal pulmonary vasculature, leading to endothelial dysfunction within a proinflammatory, vasoconstricting, and profibrogenic environment. The intricate role of stiffening-stimulated high pulsatile flow in endothelial cell dysfunction includes stepwise molecular events underlying PA hypertrophy, inflammation, endothelial-mesenchymal transition, and fibrosis. In addition to contributing to microenvironmental alterations of the distal vasculature, disordered proximal-distal PA coupling likely also plays a role in increasing ventricular afterload, ultimately causing right ventricle (RV) dysfunction and death. Current therapeutic treatments do not provide a realistic approach to destiffening arteries and, thus, to potentially abrogating the effects of high pulsatile flow on the distal pulmonary vasculature or the increased work imposed by stiffening on the RV. Scrutinizing the effect of PA stiffening on high pulsatile flow-induced cellular and molecular changes, and vice versa, might lead to important new therapeutic options that abrogate PA remodeling and PH development. With a clear understanding that PA stiffening may contribute to the progression of PH to an irreversible state by contributing to chronic microvascular damage in lungs, future studies should be aimed first at defining the underlying mechanisms leading to PA stiffening and then at improved treatment approaches based on these findings.
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Affiliation(s)
- Wei Tan
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Cardiovascular Pulmonary Research Laboratories, University of Colorado Denver, Aurora, Colorado, USA
- Department of Mechanical Engineering, University of Colorado Boulder, Boulder, Colorado, USA
| | - Krishna Madhavan
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Department of Bioengineering, University of Colorado Denver, Aurora, Colorado, USA
| | - Kendall S. Hunter
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Department of Bioengineering, University of Colorado Denver, Aurora, Colorado, USA
| | - Daewon Park
- Department of Bioengineering, University of Colorado Denver, Aurora, Colorado, USA
| | - Kurt R. Stenmark
- Department of Pediatrics, University of Colorado Denver, Aurora, Colorado, USA
- Cardiovascular Pulmonary Research Laboratories, University of Colorado Denver, Aurora, Colorado, USA
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40
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Chatterjee S, Fisher AB. Mechanotransduction in the endothelium: role of membrane proteins and reactive oxygen species in sensing, transduction, and transmission of the signal with altered blood flow. Antioxid Redox Signal 2014; 20:899-913. [PMID: 24328670 PMCID: PMC3924805 DOI: 10.1089/ars.2013.5624] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
SIGNIFICANCE Changes in shear stress associated with alterations in blood flow initiate a signaling cascade that modulates the vascular phenotype. Shear stress is "sensed" by the endothelium via a mechanosensitive complex on the endothelial cell (EC) membrane that has been characterized as a "mechanosome" consisting of caveolae, platelet endothelial cell adhesion molecule (PECAM), vascular endothelial growth factor receptor 2 (VEGFR2), vascular endothelial (VE)-cadherin, and possibly other elements. This shear signal is transduced by cell membrane ion channels and various kinases and results in the activation of NADPH oxidase (type 2) with the production of reactive oxygen species (ROS). RECENT ADVANCES The signaling cascade associated with stop of shear, as would occur in vivo with various obstructive pathologies, leads to cell proliferation and eventual revascularization. CRITICAL ISSUES AND FUTURE DIRECTIONS Although several elements of mechanosensing such as the sensing event, the transduction, transmission, and reception of the mechanosignal are now reasonably well understood, the links among these discrete steps in the pathway are not clear. Thus, identifying the mechanisms for the interaction of the K(ATP) channel, the kinases, and ROS to drive long-term adaptive responses in ECs is necessary. A critical re-examination of the signaling events associated with complex flow patterns (turbulent, oscillatory) under physiological conditions is also essential for the progress in the field. Since these complex shear patterns may be associated with an atherosclerosis susceptible phenotype, a specific challenge will be the pharmacological modulation of the responses to altered signaling events that occur at specific sites of disturbed or obstructed flow.
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Affiliation(s)
- Shampa Chatterjee
- Institute for Environmental Medicine, Perelman School of Medicine, University of Pennsylvania , Philadelphia, Pennsylvania
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41
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Dinardo CL, Venturini G, Zhou EH, Watanabe IS, Campos LCG, Dariolli R, da Motta-Leal-Filho JM, Carvalho VM, Cardozo KHM, Krieger JE, Alencar AM, Pereira AC. Variation of mechanical properties and quantitative proteomics of VSMC along the arterial tree. Am J Physiol Heart Circ Physiol 2014; 306:H505-16. [DOI: 10.1152/ajpheart.00655.2013] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Vascular smooth muscle cells (VSMCs) are thought to assume a quiescent and homogeneous mechanical behavior after arterial tree development phase. However, VSMCs are known to be molecularly heterogeneous in other aspects and their mechanics may play a role in pathological situations. Our aim was to evaluate VSMCs from different arterial beds in terms of mechanics and proteomics, as well as investigate factors that may influence this phenotype. VSMCs obtained from seven arteries were studied using optical magnetic twisting cytometry (both in static state and after stretching) and shotgun proteomics. VSMC mechanical data were correlated with anatomical parameters and ultrastructural images of their vessels of origin. Femoral, renal, abdominal aorta, carotid, mammary, and thoracic aorta exhibited descending order of stiffness (G, P < 0.001). VSMC mechanical data correlated with the vessel percentage of elastin and amount of surrounding extracellular matrix (ECM), which decreased with the distance from the heart. After 48 h of stretching simulating regional blood flow of elastic arteries, VSMCs exhibited a reduction in basal rigidity. VSMCs from the thoracic aorta expressed a significantly higher amount of proteins related to cytoskeleton structure and organization vs. VSMCs from the femoral artery. VSMCs are heterogeneous in terms of mechanical properties and expression/organization of cytoskeleton proteins along the arterial tree. The mechanical phenotype correlates with the composition of ECM and can be modulated by cyclic stretching imposed on VSMCs by blood flow circumferential stress.
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Affiliation(s)
- Carla Luana Dinardo
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
| | - Gabriela Venturini
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
| | - Enhua H. Zhou
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
| | - Ii Sei Watanabe
- Institute of Biomedical Sciences, Department of Anatomy, University of São Paulo, São Paulo, Brazil
| | | | - Rafael Dariolli
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
| | | | | | | | - José Eduardo Krieger
- Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil
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Shav D, Gotlieb R, Zaretsky U, Elad D, Einav S. Wall shear stress effects on endothelial-endothelial and endothelial-smooth muscle cell interactions in tissue engineered models of the vascular wall. PLoS One 2014; 9:e88304. [PMID: 24520363 PMCID: PMC3919748 DOI: 10.1371/journal.pone.0088304] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2013] [Accepted: 01/05/2014] [Indexed: 12/30/2022] Open
Abstract
Vascular functions are affected by wall shear stresses (WSS) applied on the endothelial cells (EC), as well as by the interactions of the EC with the adjacent smooth muscle cells (SMC). The present study was designed to investigate the effects of WSS on the endothelial interactions with its surroundings. For this purpose we developed and constructed two co-culture models of EC and SMC, and compared their response to that of a single monolayer of cultured EC. In one co-culture model the EC were cultured on the SMC, whereas in the other model the EC and SMC were cultured on the opposite sides of a membrane. We studied EC-matrix interactions through focal adhesion kinase morphology, EC-EC interactions through VE-Cadherin expression and morphology, and EC-SMC interactions through the expression of Cx43 and Cx37. In the absence of WSS the SMC presence reduced EC-EC connectivity but produced EC-SMC connections using both connexins. The exposure to WSS produced discontinuity in the EC-EC connections, with a weaker effect in the co-culture models. In the EC monolayer, WSS exposure (12 and 4 dyne/cm2 for 30 min) increased the EC-EC interaction using both connexins. WSS exposure of 12 dyne/cm2 did not affect the EC-SMC interactions, whereas WSS of 4 dyne/cm2 elevated the amount of Cx43 and reduced the amount of Cx37, with a different magnitude between the models. The reduced endothelium connectivity suggests that the presence of SMC reduces the sealing properties of the endothelium, showing a more inflammatory phenotype while the distance between the two cell types reduced their interactions. These results demonstrate that EC-SMC interactions affect EC phenotype and change the EC response to WSS. Furthermore, the interactions formed between the EC and SMC demonstrate that the 1-side model can simulate better the arterioles, while the 2-side model provides better simulation of larger arteries.
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Affiliation(s)
- Dalit Shav
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
- * E-mail:
| | - Ruth Gotlieb
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Uri Zaretsky
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - David Elad
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Shmuel Einav
- Department of Biomedical Engineering, Tel Aviv University, Tel Aviv, Israel
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