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Behringer EJ. Impact of aging on vascular ion channels: perspectives and knowledge gaps across major organ systems. Am J Physiol Heart Circ Physiol 2023; 325:H1012-H1038. [PMID: 37624095 PMCID: PMC10908410 DOI: 10.1152/ajpheart.00288.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 08/21/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
Individuals aged ≥65 yr will comprise ∼20% of the global population by 2030. Cardiovascular disease remains the leading cause of death in the world with age-related endothelial "dysfunction" as a key risk factor. As an organ in and of itself, vascular endothelium courses throughout the mammalian body to coordinate blood flow to all other organs and tissues (e.g., brain, heart, lung, skeletal muscle, gut, kidney, skin) in accord with metabolic demand. In turn, emerging evidence demonstrates that vascular aging and its comorbidities (e.g., neurodegeneration, diabetes, hypertension, kidney disease, heart failure, and cancer) are "channelopathies" in large part. With an emphasis on distinct functional traits and common arrangements across major organs systems, the present literature review encompasses regulation of vascular ion channels that underlie blood flow control throughout the body. The regulation of myoendothelial coupling and local versus conducted signaling are discussed with new perspectives for aging and the development of chronic diseases. Although equipped with an awareness of knowledge gaps in the vascular aging field, a section has been included to encompass general feasibility, role of biological sex, and additional conceptual and experimental considerations (e.g., cell regression and proliferation, gene profile analyses). The ultimate goal is for the reader to see and understand major points of deterioration in vascular function while gaining the ability to think of potential mechanistic and therapeutic strategies to sustain organ perfusion and whole body health with aging.
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Affiliation(s)
- Erik J Behringer
- Basic Sciences, Loma Linda University, Loma Linda, California, United States
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Ashton KJ, Kiessling CJ, Thompson JLM, Aziz AY, Thomas WG, Headrick JP, Reichelt ME. Early cardiac aging linked to impaired stress-resistance and transcriptional control of stress response, quality control and mitochondrial pathways. Exp Gerontol 2023; 171:112011. [PMID: 36347360 DOI: 10.1016/j.exger.2022.112011] [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: 03/20/2022] [Revised: 10/18/2022] [Accepted: 10/30/2022] [Indexed: 11/06/2022]
Abstract
Phenotypic and transcriptomic evidence of early cardiac aging, and associated mechanisms, were investigated in young to middle-aged male mice (C57Bl/6; ages 8, 16, 32, 48 wks). Left ventricular gene expression (profiled via Illumina MouseWG-6 BeadChips), contractile and coronary function, and stress-resistance were assessed in Langendorff perfused hearts under normoxic conditions and following ischemic insult (20 min global ischemia-45 min reperfusion; I-R). Baseline or normoxic contractile function was unaltered by age, while cardiac and coronary 'reserves' (during β-adrenoceptor stimulation; 1 μM isoproterenol) declined by 48 wks. Resistance to I-R injury fell from 16 to 32 wks. Age-dependent transcriptional changes In un-stressed hearts were limited to 104 genes (>1.3-fold; 0.05 FDR), supporting: up-regulated innate defenses (glutathione and xenobiotic metabolism, chemotaxis, interleukins) and catecholamine secretion; and down-regulated extracellular matrix (ECM), growth factor and survival (PI3K/Akt) signaling. In stressed (post-ischemic) myocardium, ∼15-times as many genes (1528) were age-dependent, grouped into 6 clusters (>1.3-fold change; 0.05 FDR): most changing from 16 wks (45 % up/44 % down), a further 5 % declining from 32 wks. Major age-dependent Biological Processes in I-R hearts reveal: declining ATP metabolism, oxidative phosphorylation, cardiac contraction and morphogenesis, phospholipid metabolism and calcineurin signaling; increasing proteolysis and negative control of MAPK; and mixed changes in nuclear transport and angiogenic genes. Pathway analysis supports reductions in: autophagy, stress response, ER protein processing, mRNA surveillance and ribosome/translation genes; with later falls in mitochondrial biogenesis, oxidative phosphorylation and proteasome genes in I-R hearts. Summarizing, early cardiac aging is evident from 16 to 32 wks in male mice, characterized by: declining cardiovascular reserve and stress-resistance, transcriptomic evidence of constitutive stress and altered catecholamine and survival/growth signaling in healthy hearts; and declining stress response, quality control, mitochondrial energy metabolism and cardiac modeling processes in stressed hearts. These very early changes, potentially key substrate for advanced aging, may inform approaches to healthy aging and cardioprotection in the adult heart.
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Affiliation(s)
- Kevin J Ashton
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia
| | - Can J Kiessling
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia
| | - Jamie-Lee M Thompson
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia
| | - Aliah Y Aziz
- Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, Australia
| | - Walter G Thomas
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - John P Headrick
- School of Medical Science, Griffith University, Southport, QLD, Australia
| | - Melissa E Reichelt
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia.
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Dora KA, Lin J, Borysova L, Beleznai T, Taggart M, Ascione R, Garland C. Signaling and structures underpinning conducted vasodilation in human and porcine intramyocardial coronary arteries. Front Cardiovasc Med 2022; 9:980628. [PMID: 36035957 PMCID: PMC9411971 DOI: 10.3389/fcvm.2022.980628] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 07/26/2022] [Indexed: 01/28/2023] Open
Abstract
Background Adequate blood flow into coronary micro-arteries is essential for myocardial function. Here we assess the mechanisms responsible for amplifying blood flow into myogenically-contracting human and porcine intramyocardial micro-arteries ex vivo using endothelium-dependent and -independent vasodilators. Methods Human and porcine atrial and ventricular small intramyocardial coronary arteries (IMCAs) were studied with pressure myography and imaged using confocal microscopy and serial section/3-D reconstruction EM. Results 3D rendered ultrastructure images of human right atrial (RA-) IMCAs revealed extensive homo-and hetero-cellular contacts, including to longitudinally-arranged smooth muscle cells (l-SMCs) found between the endothelial cells (ECs) and radially-arranged medial SMCs (r-SMCs). Local and conducted vasodilatation followed focal application of bradykinin in both human and porcine RA-IMCAs, and relied on hyperpolarization of SMCs, but not nitric oxide. Bradykinin initiated asynchronous oscillations in endothelial cell Ca2+ in pressurized RA-IMCAs and, as previously shown in human RA-IMCAs, hyperpolarized porcine arteries. Immunolabelling showed small- and intermediate-conductance Ca2+-activated K+ channels (KCa) present in the endothelium of both species, and concentration-dependent vasodilation to bradykinin followed activation of these KCa channels. Extensive electrical coupling was demonstrated between r-SMCs and l-SMCs, providing an additional pathway to facilitate the well-established myoendothelial coupling. Conducted dilation was still evident in a human RA-IMCA with poor myogenic tone, and heterocellular contacts were visible in the 3D reconstructed artery. Hyperpolarization and conducted vasodilation was also observed to adenosine which, in contrast to bradykinin, was sensitive to combined block of ATP-sensitive (KATP) and inwardly rectifying (KIR) K+ channels. Conclusions These data extend our understanding of the mechanisms that coordinate human coronary microvascular blood flow and the mechanistic overlap with porcine IMCAs. The unusual presence of l-SMCs provides an additional pathway for rapid intercellular signaling between cells of the coronary artery wall. Local and conducted vasodilation follow hyperpolarization of the ECs or SMCs, and contact-coupling between l-SMCs and r-SMCs likely facilitates this vasodilation.
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Affiliation(s)
- Kim A Dora
- The Vascular Pharmacology Group, Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - JinHeng Lin
- The Vascular Pharmacology Group, Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Lyudmyla Borysova
- The Vascular Pharmacology Group, Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Timea Beleznai
- The Vascular Pharmacology Group, Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Michael Taggart
- Biosciences Institute, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Raimondo Ascione
- Bristol Heart Institute and Translational Biomedical Research Centre, University of Bristol, Bristol, United Kingdom
| | - Christopher Garland
- The Vascular Pharmacology Group, Department of Pharmacology, University of Oxford, Oxford, United Kingdom
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Sabe SA, Feng J, Sellke FW, Abid MR. Mechanisms and clinical implications of endothelium-dependent vasomotor dysfunction in coronary microvasculature. Am J Physiol Heart Circ Physiol 2022; 322:H819-H841. [PMID: 35333122 PMCID: PMC9018047 DOI: 10.1152/ajpheart.00603.2021] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 03/21/2022] [Accepted: 03/21/2022] [Indexed: 12/16/2022]
Abstract
Coronary microvascular disease (CMD), which affects the arterioles and capillary endothelium that regulate myocardial perfusion, is an increasingly recognized source of morbidity and mortality, particularly in the setting of metabolic syndrome. The coronary endothelium plays a pivotal role in maintaining homeostasis, though factors such as diabetes, hypertension, hyperlipidemia, and obesity can contribute to endothelial injury and consequently arteriolar vasomotor dysfunction. These disturbances in the coronary microvasculature clinically manifest as diminished coronary flow reserve, which is a known independent risk factor for cardiac death, even in the absence of macrovascular atherosclerotic disease. Therefore, a growing body of literature has examined the molecular mechanisms by which coronary microvascular injury occurs at the level of the endothelium and the consequences on arteriolar vasomotor responses. This review will begin with an overview of normal coronary microvascular physiology, modalities of measuring coronary microvascular function, and clinical implications of CMD. These introductory topics will be followed by a discussion of recent advances in the understanding of the mechanisms by which inflammation, oxidative stress, insulin resistance, hyperlipidemia, hypertension, shear stress, endothelial cell senescence, and tissue ischemia dysregulate coronary endothelial homeostasis and arteriolar vasomotor function.
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Affiliation(s)
- Sharif A Sabe
- Cardiovascular Research Center, Rhode Island Hospital, Providence, Rhode Island
- Division of Cardiothoracic Surgery, Alpert Medical School of Brown University and Rhode Island Hospital, Providence, Rhode Island
| | - Jun Feng
- Cardiovascular Research Center, Rhode Island Hospital, Providence, Rhode Island
- Division of Cardiothoracic Surgery, Alpert Medical School of Brown University and Rhode Island Hospital, Providence, Rhode Island
| | - Frank W Sellke
- Cardiovascular Research Center, Rhode Island Hospital, Providence, Rhode Island
- Division of Cardiothoracic Surgery, Alpert Medical School of Brown University and Rhode Island Hospital, Providence, Rhode Island
| | - M Ruhul Abid
- Cardiovascular Research Center, Rhode Island Hospital, Providence, Rhode Island
- Division of Cardiothoracic Surgery, Alpert Medical School of Brown University and Rhode Island Hospital, Providence, Rhode Island
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Fopiano KA, Jalnapurkar S, Davila AC, Arora V, Bagi Z. Coronary Microvascular Dysfunction and Heart Failure with Preserved Ejection Fraction - implications for Chronic Inflammatory Mechanisms. Curr Cardiol Rev 2022; 18:e310821195986. [PMID: 34488616 PMCID: PMC9413735 DOI: 10.2174/1573403x17666210831144651] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 06/01/2021] [Accepted: 06/14/2021] [Indexed: 11/22/2022] Open
Abstract
Coronary Microvascular Dysfunction (CMD) is now considered one of the key underlying pathologies responsible for the development of both acute and chronic cardiac complications. It has been long recognized that CMD contributes to coronary no-reflow, which occurs as an acute complication during percutaneous coronary interventions. More recently, CMD was proposed to play a mechanistic role in the development of left ventricle diastolic dysfunction in heart failure with preserved ejection fraction (HFpEF). Emerging evidence indicates that a chronic low-grade pro-inflammatory activation predisposes patients to both acute and chronic cardiovascular complications raising the possibility that pro-inflammatory mediators serve as a mechanistic link in HFpEF. Few recent studies have evaluated the role of the hyaluronan-CD44 axis in inflammation-related cardiovascular pathologies, thus warranting further investigations. This review article summarizes current evidence for the role of CMD in the development of HFpEF, focusing on molecular mediators of chronic proinflammatory as well as oxidative stress mechanisms and possible therapeutic approaches to consider for treatment and prevention.
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Affiliation(s)
- Katie Anne Fopiano
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Sawan Jalnapurkar
- Division of Cardiology, Department of Medicine, Medical College of Georgia, Augusta University Augusta, GA 30912, USA
| | - Alec C Davila
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Vishal Arora
- Division of Cardiology, Department of Medicine, Medical College of Georgia, Augusta University Augusta, GA 30912, USA
| | - Zsolt Bagi
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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Shuvaeva VN, Gorshkova OP. Age-Related Changes in the Contribution of Nitric Oxide and Potassium Channels to Dilation of Rat Pial Arteries. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021060193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Tracy EP, Hughes W, Beare JE, Rowe G, Beyer A, LeBlanc AJ. Aging-Induced Impairment of Vascular Function: Mitochondrial Redox Contributions and Physiological/Clinical Implications. Antioxid Redox Signal 2021; 35:974-1015. [PMID: 34314229 PMCID: PMC8905248 DOI: 10.1089/ars.2021.0031] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Significance: The vasculature responds to the respiratory needs of tissue by modulating luminal diameter through smooth muscle constriction or relaxation. Coronary perfusion, diastolic function, and coronary flow reserve are drastically reduced with aging. This loss of blood flow contributes to and exacerbates pathological processes such as angina pectoris, atherosclerosis, and coronary artery and microvascular disease. Recent Advances: Increased attention has recently been given to defining mechanisms behind aging-mediated loss of vascular function and development of therapeutic strategies to restore youthful vascular responsiveness. The ultimate goal aims at providing new avenues for symptom management, reversal of tissue damage, and preventing or delaying of aging-induced vascular damage and dysfunction in the first place. Critical Issues: Our major objective is to describe how aging-associated mitochondrial dysfunction contributes to endothelial and smooth muscle dysfunction via dysregulated reactive oxygen species production, the clinical impact of this phenomenon, and to discuss emerging therapeutic strategies. Pathological changes in regulation of mitochondrial oxidative and nitrosative balance (Section 1) and mitochondrial dynamics of fission/fusion (Section 2) have widespread effects on the mechanisms underlying the ability of the vasculature to relax, leading to hyperconstriction with aging. We will focus on flow-mediated dilation, endothelial hyperpolarizing factors (Sections 3 and 4), and adrenergic receptors (Section 5), as outlined in Figure 1. The clinical implications of these changes on major adverse cardiac events and mortality are described (Section 6). Future Directions: We discuss antioxidative therapeutic strategies currently in development to restore mitochondrial redox homeostasis and subsequently vascular function and evaluate their potential clinical impact (Section 7). Antioxid. Redox Signal. 35, 974-1015.
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Affiliation(s)
- Evan Paul Tracy
- Department of Physiology, University of Louisville, Louisville, Kentucky, USA
| | - William Hughes
- Department of Medicine and Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Jason E Beare
- Cardiovascular Innovation Institute, University of Louisville, Louisville, Kentucky, USA.,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA
| | - Gabrielle Rowe
- Department of Physiology, University of Louisville, Louisville, Kentucky, USA
| | - Andreas Beyer
- Department of Medicine and Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Amanda Jo LeBlanc
- Department of Physiology, University of Louisville, Louisville, Kentucky, USA.,Cardiovascular Innovation Institute, University of Louisville, Louisville, Kentucky, USA
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Gorshkova OP. Age-Related Changes in the Role of
Potassium Channels in Acetylcholine-Induced Dilation of Pial Arteries in Normotensive
and Spontaneously Hypertensive Rats. J EVOL BIOCHEM PHYS+ 2021. [DOI: 10.1134/s0022093021010051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Saljic A, Soattin L, Trachsel DS, Boddum K, Jespersen T. In vivo knockdown of SK3 channels using antisense oligonucleotides protects against atrial fibrillation in rats. J Mol Cell Cardiol 2020; 147:18-26. [PMID: 32768409 DOI: 10.1016/j.yjmcc.2020.07.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 07/06/2020] [Accepted: 07/28/2020] [Indexed: 02/02/2023]
Abstract
INTRODUCTION GapmeRs are oligonucleotides that bind to a specific RNA sequence and thereby affecting posttranscriptional gene regulation. They therefore hold the potential to manipulate targets where current pharmacological modulators are inefficient or exhibit adverse side effects. Here, we show that a treatment with a GapmeR, mediating knockdown of small conductance Ca2+-activated K+ channels (SK3), has an in vivo protective effect against atrial fibrillation (AF) in rats. MATERIAL AND METHODS A unique SK3-GapmeR design was selected after thorough in vitro evaluation. 22 rats were randomly assigned to receive either 50 mg/kg SK3-GapmeR or vehicle subcutaneously once a week for two weeks. Langendorff experiments were performed seven days after the last injection, where action potential duration (APD90), effective refractory period (ERP) and AF propensity were investigated. SK3 channel activity was evaluated using the SK channel blocker, ICA (N-(pyridin-2-yl)-4-(pyridine-2-yl)thiazol-2-amine). SK3 protein expression was assessed by Western Blot. RESULTS The designed GapmeR effectively down-regulate the SK3 protein expression in the heart (48% downregulation, p = 0.0095) and did indeed protect against AF. Duration of AF episodes elicited by burst pacing in the rats treated with SK3-GapmeR was reduced 78% compared to controls (3.7 s vs. 16.8 s, p = 0.0353). The number of spontaneous AF episodes were decreased by 68% in the SK3-GapmeR group (39 episodes versus 123 in the control group, respectively) and were also significantly shorter in duration (7.2 s versus 29.7 s in the control group, p = 0.0327). Refractoriness was not altered at sinus rhythm, but ERP prolongation following ICA application was blunted in the SK3-GapmeR group. CONCLUSION The selected GapmeR silenced the cardiac SK3 channels, thereby preventing AF in rats. Thus, GapmeR technology can be applied as an experimental tool of downregulation of cardiac proteins and could potentially offer a novel modality for treatment of cardiac diseases.
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Affiliation(s)
- Arnela Saljic
- Laboratory of Cardiac Physiology, Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark
| | - Luca Soattin
- Division of Cardiovascular Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, United Kingdom; Laboratory of Cardiac Physiology, Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark
| | - Dagmar S Trachsel
- Laboratory of Cardiac Physiology, Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark
| | - Kim Boddum
- Laboratory of Cardiac Physiology, Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark
| | - Thomas Jespersen
- Laboratory of Cardiac Physiology, Faculty of Health and Medical Sciences, Department of Biomedical Sciences, University of Copenhagen, Blegdamsvej 3B, DK-2200 Copenhagen, Denmark.
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Sukumaran V, Tsuchimochi H, Sonobe T, Waddingham MT, Shirai M, Pearson JT. Liraglutide treatment improves the coronary microcirculation in insulin resistant Zucker obese rats on a high salt diet. Cardiovasc Diabetol 2020; 19:24. [PMID: 32093680 PMCID: PMC7038553 DOI: 10.1186/s12933-020-01000-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 02/13/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Obesity, hypertension and prediabetes contribute greatly to coronary artery disease, heart failure and vascular events, and are the leading cause of mortality and morbidity in developed societies. Salt sensitivity exacerbates endothelial dysfunction. Herein, we investigated the effect of chronic glucagon like peptide-1 (GLP-1) receptor activation on the coronary microcirculation and cardiac remodeling in Zucker rats on a high-salt diet (6% NaCl). METHODS Eight-week old Zucker lean (+/+) and obese (fa/fa) rats were treated with vehicle or liraglutide (LIRA) (0.1 mg/kg/day, s.c.) for 8 weeks. Systolic blood pressure (SBP) was measured using tail-cuff method in conscious rats. Myocardial function was assessed by echocardiography. Synchrotron contrast microangiography was then used to investigate coronary arterial vessel function (vessels 50-350 µm internal diameter) in vivo in anesthetized rats. Myocardial gene and protein expression levels of vasoactive factors, inflammatory, oxidative stress and remodeling markers were determined by real-time PCR and Western blotting. RESULTS We found that in comparison to the vehicle-treated fa/fa rats, rats treated with LIRA showed significant improvement in acetylcholine-mediated vasodilation in the small arteries and arterioles (< 150 µm diameter). Neither soluble guanylyl cyclase or endothelial NO synthase (eNOS) mRNA levels or total eNOS protein expression in the myocardium were significantly altered by LIRA. However, LIRA downregulated Nox-1 mRNA (p = 0.030) and reduced ET-1 protein (p = 0.044) expression. LIRA significantly attenuated the expressions of proinflammatory and profibrotic associated biomarkers (NF-κB, CD68, IL-1β, TGF-β1, osteopontin) and nitrotyrosine in comparison to fa/fa-Veh rats, but did not attenuate perivascular fibrosis appreciably. CONCLUSIONS In a rat model of metabolic syndrome, chronic LIRA treatment improved the capacity for NO-mediated dilation throughout the coronary macro and microcirculations and partially normalized myocardial remodeling independent of changes in body mass or blood glucose.
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Affiliation(s)
- Vijayakumar Sukumaran
- Department of Basic Medical Sciences, College of Medicine, Member of QU Health, Qatar University, Doha, Qatar. .,Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan. .,Department of Pharmacology, College of Medicine, Member of QU Health, Qatar University, Doha, Qatar.
| | - Hirotsugu Tsuchimochi
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan
| | - Takashi Sonobe
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan
| | - Mark T Waddingham
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan.,Department of Advanced Medical Research in Pulmonary Hypertension, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan
| | - Mikiyasu Shirai
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan
| | - James T Pearson
- Department of Cardiac Physiology, National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, 564-8565, Japan.,Department of Physiology, Monash Biomedicine Discovery Institute, Monash University, Clayton, 3800, Australia
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Piccirillo F, Carpenito M, Verolino G, Chello C, Nusca A, Lusini M, Spadaccio C, Nappi F, Di Sciascio G, Nenna A. Changes of the coronary arteries and cardiac microvasculature with aging: Implications for translational research and clinical practice. Mech Ageing Dev 2019; 184:111161. [PMID: 31647940 DOI: 10.1016/j.mad.2019.111161] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 10/09/2019] [Accepted: 10/14/2019] [Indexed: 12/28/2022]
Abstract
Aging results in functional and structural changes in the cardiovascular system, translating into a progressive increase of mechanical vessel stiffness, due to a combination of changes in micro-RNA expression patterns, autophagy, arterial calcification, smooth muscle cell migration and proliferation. The two pivotal mechanisms of aging-related endothelial dysfunction are oxidative stress and inflammation, even in the absence of clinical disease. A comprehensive understanding of the aging process is emerging as a primary concern in literature, as vascular aging has recently become a target for prevention and treatment of cardiovascular disease. Change of life-style, diet, antioxidant regimens, anti-inflammatory treatments, senolytic drugs counteract the pro-aging pathways or target senescent cells modulating their detrimental effects. Such therapies aim to reduce the ineluctable burden of age and contrast aging-associated cardiovascular dysfunction. This narrative review intends to summarize the macrovascular and microvascular changes related with aging, as a better understanding of the pathways leading to arterial aging may contribute to design new mechanism-based therapeutic approaches to attenuate the features of vascular senescence and its clinical impact on the cardiovascular system.
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Affiliation(s)
| | | | | | - Camilla Chello
- Dermatology, Università "La Sapienza" di Roma, Rome, Italy
| | | | - Mario Lusini
- Cardiovascular surgery, Università Campus Bio-Medico di Roma, Rome, Italy
| | | | - Francesco Nappi
- Cardiac surgery, Centre Cardiologique du Nord de Saint Denis, Paris, France
| | | | - Antonio Nenna
- Cardiovascular surgery, Università Campus Bio-Medico di Roma, Rome, Italy.
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13
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Davila A, Tian Y, Czikora I, Li J, Su H, Huo Y, Patel V, Robinson V, Kapuku G, Weintraub N, Bagi Z. Adenosine Kinase Inhibition Augments Conducted Vasodilation and Prevents Left Ventricle Diastolic Dysfunction in Heart Failure With Preserved Ejection Fraction. Circ Heart Fail 2019; 12:e005762. [PMID: 31525084 DOI: 10.1161/circheartfailure.118.005762] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND Heart failure with preserved ejection fraction (HFpEF) is often manifested as impaired cardiovascular reserve. We sought to determine if conducted vasodilation, which coordinates microvascular resistance longitudinally to match tissue metabolic demand, becomes compromised in HFpEF. We hypothesized that the metabolic vasodilator adenosine facilitates and that inhibition of ADK (adenosine kinase) augments conducted vasodilation for a more efficient myocardial perfusion and improved left ventricle (LV) diastolic function in HFpEF. METHODS AND RESULTS We assessed conducted vasodilation in obese ZSF1 rats that develop LV diastolic dysfunction and is used to model human HFpEF. Additionally, conducted vasodilation was measured in arterioles isolated from the right atrial appendages of patients with HFpEF. We found a markedly reduced conducted vasodilation both in obese ZSF1 rats and in patients with HFpEF. Impaired conducted vasodilation was accompanied by increased vascular ADK expression. Isolated rat and human arterioles incubated with adenosine (10 nmol/L) or ADK inhibitor ABT-702 (0.1 µmol/L) both displayed augmented conducted vasodilation. Treatment of obese ZSF1 rats with ABT-702 (1.5 mg/kg, IP for 8 weeks) prevented LV diastolic dysfunction, and in a crossover design augmented conducted vasodilation and improved LV diastolic function. ABT-702 treated obese ZSF1 rats exhibited reduced expression of myocardial carbonic anhydrase 9 and collagen, surrogate markers of myocardial hypoxia. CONCLUSIONS Upregulation of vascular ADK mitigates adenosine-facilitated conducted vasodilation in obese ZSF1 rats and in patients with HFpEF. We propose that pharmacological inhibition of ADK could be beneficial for therapeutic augmentation of conducted vasodilation, thereby improving tissue perfusion and LV diastolic function in HFpEF.
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Affiliation(s)
- Alec Davila
- Department of Physiology (A.D., Y.T., I.C., Z.B.), Medical College of Georgia, Augusta University
| | - Yanna Tian
- Department of Physiology (A.D., Y.T., I.C., Z.B.), Medical College of Georgia, Augusta University
| | - Istvan Czikora
- Department of Physiology (A.D., Y.T., I.C., Z.B.), Medical College of Georgia, Augusta University
| | - Jie Li
- Vascular Biology Center (J.L., H.S., Y.H., N.W.), Medical College of Georgia, Augusta University
| | - Huabo Su
- Vascular Biology Center (J.L., H.S., Y.H., N.W.), Medical College of Georgia, Augusta University
| | - Yuqing Huo
- Vascular Biology Center (J.L., H.S., Y.H., N.W.), Medical College of Georgia, Augusta University
| | - Vijay Patel
- Department of Surgery (V.P.), Medical College of Georgia, Augusta University
| | - Vincent Robinson
- Division of Cardiology (V.R., N.W.), Medical College of Georgia, Augusta University
| | - Gaston Kapuku
- Department of Medicine, Georgia Prevention Institute, Department of Population Health Sciences (G.K.), Medical College of Georgia, Augusta University
| | - Neal Weintraub
- Vascular Biology Center (J.L., H.S., Y.H., N.W.), Medical College of Georgia, Augusta University.,Division of Cardiology (V.R., N.W.), Medical College of Georgia, Augusta University
| | - Zsolt Bagi
- Department of Physiology (A.D., Y.T., I.C., Z.B.), Medical College of Georgia, Augusta University
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14
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Sukumaran V, Tsuchimochi H, Sonobe T, Shirai M, Pearson JT. Liraglutide Improves Renal Endothelial Function in Obese Zucker Rats on a High-Salt Diet. J Pharmacol Exp Ther 2019; 369:375-388. [DOI: 10.1124/jpet.118.254821] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 03/21/2019] [Indexed: 01/11/2023] Open
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15
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Behringer EJ, Hakim MA. Functional Interaction among K Ca and TRP Channels for Cardiovascular Physiology: Modern Perspectives on Aging and Chronic Disease. Int J Mol Sci 2019; 20:ijms20061380. [PMID: 30893836 PMCID: PMC6471369 DOI: 10.3390/ijms20061380] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/07/2019] [Accepted: 03/15/2019] [Indexed: 12/16/2022] Open
Abstract
Effective delivery of oxygen and essential nutrients to vital organs and tissues throughout the body requires adequate blood flow supplied through resistance vessels. The intimate relationship between intracellular calcium ([Ca2+]i) and regulation of membrane potential (Vm) is indispensable for maintaining blood flow regulation. In particular, Ca2+-activated K+ (KCa) channels were ascertained as transducers of elevated [Ca2+]i signals into hyperpolarization of Vm as a pathway for decreasing vascular resistance, thereby enhancing blood flow. Recent evidence also supports the reverse role for KCa channels, in which they facilitate Ca2+ influx into the cell interior through open non-selective cation (e.g., transient receptor potential; TRP) channels in accord with robust electrical (hyperpolarization) and concentration (~20,000-fold) transmembrane gradients for Ca2+. Such an arrangement supports a feed-forward activation of Vm hyperpolarization while potentially boosting production of nitric oxide. Furthermore, in vascular types expressing TRP channels but deficient in functional KCa channels (e.g., collecting lymphatic endothelium), there are profound alterations such as downstream depolarizing ionic fluxes and the absence of dynamic hyperpolarizing events. Altogether, this review is a refined set of evidence-based perspectives focused on the role of the endothelial KCa and TRP channels throughout multiple experimental animal models and vascular types. We discuss the diverse interactions among KCa and TRP channels to integrate Ca2+, oxidative, and electrical signaling in the context of cardiovascular physiology and pathology. Building from a foundation of cellular biophysical data throughout a wide and diverse compilation of significant discoveries, a translational narrative is provided for readers toward the treatment and prevention of chronic, age-related cardiovascular disease.
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Affiliation(s)
- Erik J Behringer
- Department of Basic Sciences, 11041 Campus Street, Risley Hall, Loma Linda University, Loma Linda, CA 92350, USA.
| | - Md A Hakim
- Department of Basic Sciences, 11041 Campus Street, Risley Hall, Loma Linda University, Loma Linda, CA 92350, USA.
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16
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Gu M, Zhu Y, Yin X, Zhang DM. Small-conductance Ca 2+-activated K + channels: insights into their roles in cardiovascular disease. Exp Mol Med 2018; 50:1-7. [PMID: 29651007 PMCID: PMC5938042 DOI: 10.1038/s12276-018-0043-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Revised: 12/11/2017] [Accepted: 12/12/2017] [Indexed: 12/13/2022] Open
Abstract
Life-threatening malignant arrhythmias in pathophysiological conditions can increase the mortality and morbidity of patients with cardiovascular diseases. Cardiac electrical activity depends on the coordinated propagation of excitatory stimuli and the generation of action potentials in cardiomyocytes. Action potential formation results from the opening and closing of ion channels. Recent studies have indicated that small-conductance calcium-activated potassium (SK) channels play a critical role in cardiac repolarization in pathophysiological but not normal physiological conditions. The aim of this review is to describe the role of SK channels in healthy and diseased hearts, to suggest cardiovascular pathophysiologic targets for intervention, and to discuss studies of agents that target SK channels for the treatment of cardiovascular diseases.
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Affiliation(s)
- Mingxia Gu
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Jiangsu, 210006, Nanjing, China
- Department of Cardiology, Nanjing Central Hospital, Jiangsu, 210018, Nanjing, China
| | - Yanrong Zhu
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Jiangsu, 210006, Nanjing, China
| | - Xiaorong Yin
- Department of Cardiology, Nanjing Central Hospital, Jiangsu, 210018, Nanjing, China
| | - Dai-Min Zhang
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Jiangsu, 210006, Nanjing, China.
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17
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Carvajal FJ, Mira RG, Rovegno M, Minniti AN, Cerpa W. Age-related NMDA signaling alterations in SOD2 deficient mice. Biochim Biophys Acta Mol Basis Dis 2018; 1864:2010-2020. [PMID: 29577983 DOI: 10.1016/j.bbadis.2018.03.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 03/19/2018] [Accepted: 03/20/2018] [Indexed: 12/23/2022]
Abstract
Oxidative stress affects the survival and function of neurons. Hence, they have a complex and highly regulated machinery to handle oxidative changes. The dysregulation of this antioxidant machinery is associated with a wide range of neurodegenerative conditions. Therefore, we evaluated signaling alterations, synaptic properties and behavioral performance in 2 and 6-month-old heterozygous manganese superoxide dismutase knockout mice (SOD2+/- mice). We found that their low antioxidant capacity generated direct oxidative damage in proteins, lipids, and DNA. However, only 6-month-old heterozygous knockout mice presented behavioral impairments. On the other hand, synaptic plasticity, synaptic strength and NMDA receptor (NMDAR) dependent postsynaptic potentials were decreased in an age-dependent manner. We also analyzed the phosphorylation state of the NMDAR subunit GluN2B. We found that while the levels of GluN2B phosphorylated on tyrosine 1472 (synaptic form) remain unchanged, we detected increased levels of GluN2B phosphorylated on tyrosine 1336 (extrasynaptic form), establishing alterations in the synaptic/extrasynaptic ratio of GluN2B. Additionally, we found increased levels of two phosphatases associated with dephosphorylation of p-1472: striatal-enriched protein tyrosine phosphatase (STEP) and phosphatase and tensin homolog deleted on chromosome Ten (PTEN). Moreover, we found decreased levels of p-CREB, a master transcription factor activated by synaptic stimulation. In summary, we describe mechanisms by which glutamatergic synapses are altered under oxidative stress conditions. Our results uncovered new putative therapeutic targets for conditions where NMDAR downstream signaling is altered. This work also contributes to our understanding of processes such as synapse formation, learning, and memory in neuropathological conditions.
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Affiliation(s)
- Francisco J Carvajal
- Laboratorio de Función y Patología Neuronal, Santiago, Chile; Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Santiago, Chile; Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Rodrigo G Mira
- Laboratorio de Función y Patología Neuronal, Santiago, Chile; Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Santiago, Chile; Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Maximiliano Rovegno
- Departamento de Medicina Intensiva, Facultad de Medicina, Santiago, Chile; Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Alicia N Minniti
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Santiago, Chile; Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Waldo Cerpa
- Laboratorio de Función y Patología Neuronal, Santiago, Chile; Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Santiago, Chile; Pontificia Universidad Católica de Chile, Santiago, Chile.
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18
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Behringer EJ. Calcium and electrical signaling in arterial endothelial tubes: New insights into cellular physiology and cardiovascular function. Microcirculation 2018; 24. [PMID: 27801542 DOI: 10.1111/micc.12328] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 10/25/2016] [Indexed: 12/23/2022]
Abstract
The integral role of the endothelium during the coordination of blood flow throughout vascular resistance networks has been recognized for several decades now. Early examination of the distinct anatomy and physiology of the endothelium as a signaling conduit along the vascular wall has prompted development and application of an intact endothelial "tube" study model isolated from rodent skeletal muscle resistance arteries. Vasodilatory signals such as increased endothelial cell (EC) Ca2+ ([Ca2+ ]i ) and hyperpolarization take place in single ECs while shared between electrically coupled ECs through gap junctions up to distances of millimeters (≥2 mm). The small- and intermediate-conductance Ca2+ activated K+ (SKCa /IKCa or KCa 2.3/KCa 3.1) channels function at the interface of Ca2+ signaling and hyperpolarization; a bidirectional relationship whereby increases in [Ca2+ ]i activate SKCa /IKCa channels to produce hyperpolarization and vice versa. Further, the spatial domain of hyperpolarization among electrically coupled ECs can be finely tuned via incremental modulation of SKCa /IKCa channels to balance the strength of local and conducted electrical signals underlying vasomotor activity. Multifunctional properties of the voltage-insensitive SKCa /IKCa channels of resistance artery endothelium may be employed for therapy during the aging process and development of vascular disease.
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Affiliation(s)
- Erik J Behringer
- Department of Basic Sciences, Loma Linda University, Loma Linda, CA, USA
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19
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Cazaubon Y, Mauprivez C, Feliu C, Binet L, Oget O, Gozalo C, Djerada Z. Population pharmacokinetics of articaine with 1:200,000 epinephrine during third molar surgery and simulation of high-dose regimens. Eur J Pharm Sci 2018; 114:38-45. [PMID: 29197630 DOI: 10.1016/j.ejps.2017.11.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 11/28/2017] [Accepted: 11/28/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND AND OBJECTIVES Articaine is more and more used in third molar surgery under local anesthesia (LA). The objectives of this analysis were to characterize the pharmacokinetics of articaine for this type of surgery and to simulate dosing regimens. METHODS Non-linear mixed-effects modeling conducted in Monolix 4.4.0 was used to describe articaine plasma concentration-time data from 20 patients. Monte Carlo simulations were then performed to evaluate the probability of cardiotoxic target attainment (PCTA) of various dosage regimens. RESULTS Articaine concentration data were best described by a linear one-compartment model, with an additional depot compartment for submucosal route with a zero-order transfer to central compartment. Age and gender were found to influence duration transfer (Tk0) and elimination rate constant (Ke), respectively. Simulated maximum recommended dose regimen (7mg/kg) had a PCTA of 0%. Simulated higher doses of 10mg/kg and 15mg/kg had a PCTA of 0% and about 1-4%, respectively. CONCLUSIONS The model adequately described the articaine pharmacokinetics. This is the first PK model qualified for articaine administered by submucosal route. The simulations suggest that maximum recommended dose regimen is safe concerning the cardiotoxicity in healthy patients.
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Affiliation(s)
- Yoann Cazaubon
- Department of Pharmacology and Toxicology, Pharmacology and Toxicology Laboratory, Reims University Hospital, 45 rue Cognacq Jay, Reims 51092, France; Department of Pharmacology, EA3801, SFR CAP-santé, URCA Reims University, Reims 51100, France
| | - Cédric Mauprivez
- Department of Odontology, Reims University Hospitals, 45 rue Cognacq Jay, Reims 51092, France; EA4691, Biomatériaux et Inflammation en Site Osseux, URCA Reims University, 51 rue Cognacq Jay, Reims 51092, France
| | - Catherine Feliu
- Department of Pharmacology and Toxicology, Pharmacology and Toxicology Laboratory, Reims University Hospital, 45 rue Cognacq Jay, Reims 51092, France; Department of Pharmacology, EA3801, SFR CAP-santé, URCA Reims University, Reims 51100, France
| | - Laurent Binet
- Department of Pharmacology and Toxicology, Pharmacology and Toxicology Laboratory, Reims University Hospital, 45 rue Cognacq Jay, Reims 51092, France
| | - Olivier Oget
- Department of Pharmacology and Toxicology, Pharmacology and Toxicology Laboratory, Reims University Hospital, 45 rue Cognacq Jay, Reims 51092, France
| | - Claire Gozalo
- Department of Pharmacology and Toxicology, Pharmacology and Toxicology Laboratory, Reims University Hospital, 45 rue Cognacq Jay, Reims 51092, France
| | - Zoubir Djerada
- Department of Pharmacology and Toxicology, Pharmacology and Toxicology Laboratory, Reims University Hospital, 45 rue Cognacq Jay, Reims 51092, France; Department of Pharmacology, EA3801, SFR CAP-santé, URCA Reims University, Reims 51100, France.
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20
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Dora KA. Endothelial-smooth muscle cell interactions in the regulation of vascular tone in skeletal muscle. Microcirculation 2018; 23:626-630. [PMID: 27653241 DOI: 10.1111/micc.12322] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 09/19/2016] [Indexed: 11/28/2022]
Abstract
The SMCs of skeletal muscle arterioles are intricately sensitive to changes in membrane potential. Upon increasing luminal pressure, the SMCs depolarize, thereby opening VDCCs, which leads to contraction. Mechanisms that oppose this myogenic tone can involve voltage-dependent and independent dilator pathways, and can be endothelium-dependent or independent. Of particular interest are the pathways leading to hyperpolarization of SMCs, as these can potentially evoke both local and conducted dilation. This review focuses on three agonists that cause local and conducted dilation in skeletal muscle: ACh, ATP, and KCl. The mechanisms for the release of these agonists during motor nerve stimulation and/or hypoxia, and their actions to open either Ca2+ -activated K+ channels (KCa ) or inwardly rectifying K+ channels (KIR ) are described. By causing local and conducted dilation, each agonist has the ability to improve skeletal muscle blood flow during exercise and ischemia.
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Affiliation(s)
- Kim A Dora
- Department of Pharmacology, University of Oxford, Oxford, UK
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21
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Pearson JT, Yoshimoto M, Chen YC, Sultani R, Edgley AJ, Nakaoka H, Nishida M, Umetani K, Waddingham MT, Jin HL, Zhang Y, Kelly DJ, Schwenke DO, Inagaki T, Tsuchimochi H, Komuro I, Yamashita S, Shirai M. Widespread Coronary Dysfunction in the Absence of HDL Receptor SR-B1 in an Ischemic Cardiomyopathy Mouse Model. Sci Rep 2017; 7:18108. [PMID: 29273789 PMCID: PMC5741771 DOI: 10.1038/s41598-017-18485-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 12/12/2017] [Indexed: 02/02/2023] Open
Abstract
Reduced clearance of lipoproteins by HDL scavenger receptor class B1 (SR-B1) plays an important role in occlusive coronary artery disease. However, it is not clear how much microvascular dysfunction contributes to ischemic cardiomyopathy. Our aim was to determine the distribution of vascular dysfunction in vivo in the coronary circulation of male mice after brief exposure to Paigen high fat diet, and whether this vasomotor dysfunction involved nitric oxide (NO) and or endothelium derived hyperpolarization factors (EDHF). We utilised mice with hypomorphic ApoE lipoprotein that lacked SR-B1 (SR-B1−/−/ApoER61h/h, n = 8) or were heterozygous for SR-B1 (SR-B1+/−/ApoER61h/h, n = 8) to investigate coronary dilator function with synchrotron microangiography. Partially occlusive stenoses were observed in vivo in SR-B1 deficient mice only. Increases in artery-arteriole calibre to acetylcholine and sodium nitroprusside stimulation were absent in SR-B1 deficient mice. Residual dilation to acetylcholine following L-NAME (50 mg/kg) and sodium meclofenamate (3 mg/kg) blockade was present in both mouse groups, except at occlusions, indicating that EDHF was not impaired. We show that SR-B1 deficiency caused impairment of NO-mediated dilation of conductance and microvessels. Our findings also suggest EDHF and prostanoids are important for global perfusion, but ultimately the loss of NO-mediated vasodilation contributes to atherothrombotic progression in ischemic cardiomyopathy.
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Affiliation(s)
- James T Pearson
- Monash Biomedical Imaging Facility, Melbourne, Victoria, Australia. .,Department of Physiology, Monash University, Melbourne, Victoria, Australia. .,Australian Synchrotron, Melbourne, Victoria, Australia. .,National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.
| | - Misa Yoshimoto
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan.,Department of Health Sciences, Nara Women's University, Nara, Japan
| | - Yi Ching Chen
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Rohullah Sultani
- Department of Physiology, Monash University, Melbourne, Victoria, Australia
| | - Amanda J Edgley
- Department of Physiology, Monash University, Melbourne, Victoria, Australia.,St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Hajime Nakaoka
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Makoto Nishida
- Department of Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan
| | - Keiji Umetani
- Japan Synchrotron Radiation Research Institute, Harima, Hyogo, Japan
| | - Mark T Waddingham
- St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Hui-Ling Jin
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | - Yuan Zhang
- St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Darren J Kelly
- St Vincent's Hospital, University of Melbourne, Melbourne, Victoria, Australia
| | - Daryl O Schwenke
- Department of Physiology - HeartOtago, University of Otago, Dunedin, New Zealand
| | - Tadakatsu Inagaki
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
| | | | - Issei Komuro
- Department of Cardiovascular Medicine, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Shizuya Yamashita
- Departments of Community Medicine and Cardiovascular Medicine, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan.,Rinku General Medical Center, Izumisano, Osaka, Japan
| | - Mikiyasu Shirai
- National Cerebral and Cardiovascular Center Research Institute, Suita, Osaka, Japan
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22
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Behringer EJ, Segal SS. Impact of Aging on Calcium Signaling and Membrane Potential in Endothelium of Resistance Arteries: A Role for Mitochondria. J Gerontol A Biol Sci Med Sci 2017; 72:1627-1637. [PMID: 28510636 DOI: 10.1093/gerona/glx079] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 04/21/2017] [Indexed: 12/20/2022] Open
Abstract
Impaired blood flow to peripheral tissues during advanced age is associated with endothelial dysfunction and diminished bioavailability of nitric oxide (NO). However, it is unknown whether aging impacts coupling between intracellular calcium ([Ca2+]i) signaling and small- and intermediate K+ channel (SKCa/IKCa) activity during endothelium-derived hyperpolarization (EDH), a signaling pathway integral to dilation of the resistance vasculature. To address the potential impact of aging on EDH, Fura-2 photometry and intracellular recording were applied to evaluate [Ca2+]i and membrane potential of intact endothelial tubes (width, 60 µm; length, 1-3 mm) freshly isolated from superior epigastric arteries of young (4-6 mo) and old (24-26 mo) male C57BL/6 mice. In response to acetylcholine, intracellular release of Ca2+ from the endoplasmic reticulum (ER) was enhanced with aging. Further, treatment with the mitochondrial uncoupler FCCP evoked a significant increase of [Ca2+]i with membrane hyperpolarization in an SKCa/IKCa-dependent manner in the endothelium of old but not young mice. We conclude that the ability of resistance artery endothelium to release Ca2+ from intracellular stores (ie, ER and mitochondria) and hyperpolarize Vm via SKCa/IKCa activation is augmented as compensation for reduced NO bioavailability during advanced age.
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Affiliation(s)
- Erik J Behringer
- Department of Basic Sciences, Loma Linda University, California.,Department of Medical Pharmacology and Physiology, University of Missouri, Columbia
| | - Steven S Segal
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia.,Dalton Cardiovascular Research Center, Columbia, Missouri
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23
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Zhou T, Huang X, Cai X, Xie L. Combined treatment of irbesartan and diltiazem ameliorates endothelium dependent vasodilatation in hypertensives. Clin Exp Hypertens 2017; 39:612-618. [PMID: 28613098 DOI: 10.1080/10641963.2017.1306537] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Tingting Zhou
- Fujian Medical University, Fujian Hypertension Research Institute, Fuzhou, P.R. China
| | - Xiaodong Huang
- Fujian Hypertension Research Institute, First Affiliated Hospital of Fujian Medical University, Fuzhou, PR China
| | - Xiaoqi Cai
- Fujian Hypertension Research Institute, First Affiliated Hospital of Fujian Medical University, Fuzhou, PR China
| | - Liangdi Xie
- Fujian Hypertension Research Institute, First Affiliated Hospital of Fujian Medical University, Fuzhou, PR China
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24
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Abstract
The heart is uniquely responsible for providing its own blood supply through the coronary circulation. Regulation of coronary blood flow is quite complex and, after over 100 years of dedicated research, is understood to be dictated through multiple mechanisms that include extravascular compressive forces (tissue pressure), coronary perfusion pressure, myogenic, local metabolic, endothelial as well as neural and hormonal influences. While each of these determinants can have profound influence over myocardial perfusion, largely through effects on end-effector ion channels, these mechanisms collectively modulate coronary vascular resistance and act to ensure that the myocardial requirements for oxygen and substrates are adequately provided by the coronary circulation. The purpose of this series of Comprehensive Physiology is to highlight current knowledge regarding the physiologic regulation of coronary blood flow, with emphasis on functional anatomy and the interplay between the physical and biological determinants of myocardial oxygen delivery. © 2017 American Physiological Society. Compr Physiol 7:321-382, 2017.
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Affiliation(s)
- Adam G Goodwill
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
| | - Gregory M Dick
- California Medical Innovations Institute, 872 Towne Center Drive, Pomona, CA
| | - Alexander M Kiel
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
- Weldon School of Biomedical Engineering, Purdue University, 206 S Martin Jischke Drive, Lafayette, IN
| | - Johnathan D Tune
- Department of Cellular and Integrative Physiology, Indiana University School of Medicine, Indianapolis, IN
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25
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Vanhoutte PM, Shimokawa H, Feletou M, Tang EHC. Endothelial dysfunction and vascular disease - a 30th anniversary update. Acta Physiol (Oxf) 2017; 219:22-96. [PMID: 26706498 DOI: 10.1111/apha.12646] [Citation(s) in RCA: 581] [Impact Index Per Article: 83.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 10/27/2015] [Accepted: 12/17/2015] [Indexed: 02/06/2023]
Abstract
The endothelium can evoke relaxations of the underlying vascular smooth muscle, by releasing vasodilator substances. The best-characterized endothelium-derived relaxing factor (EDRF) is nitric oxide (NO) which activates soluble guanylyl cyclase in the vascular smooth muscle cells, with the production of cyclic guanosine monophosphate (cGMP) initiating relaxation. The endothelial cells also evoke hyperpolarization of the cell membrane of vascular smooth muscle (endothelium-dependent hyperpolarizations, EDH-mediated responses). As regards the latter, hydrogen peroxide (H2 O2 ) now appears to play a dominant role. Endothelium-dependent relaxations involve both pertussis toxin-sensitive Gi (e.g. responses to α2 -adrenergic agonists, serotonin, and thrombin) and pertussis toxin-insensitive Gq (e.g. adenosine diphosphate and bradykinin) coupling proteins. New stimulators (e.g. insulin, adiponectin) of the release of EDRFs have emerged. In recent years, evidence has also accumulated, confirming that the release of NO by the endothelial cell can chronically be upregulated (e.g. by oestrogens, exercise and dietary factors) and downregulated (e.g. oxidative stress, smoking, pollution and oxidized low-density lipoproteins) and that it is reduced with ageing and in the course of vascular disease (e.g. diabetes and hypertension). Arteries covered with regenerated endothelium (e.g. following angioplasty) selectively lose the pertussis toxin-sensitive pathway for NO release which favours vasospasm, thrombosis, penetration of macrophages, cellular growth and the inflammatory reaction leading to atherosclerosis. In addition to the release of NO (and EDH, in particular those due to H2 O2 ), endothelial cells also can evoke contraction of the underlying vascular smooth muscle cells by releasing endothelium-derived contracting factors. Recent evidence confirms that most endothelium-dependent acute increases in contractile force are due to the formation of vasoconstrictor prostanoids (endoperoxides and prostacyclin) which activate TP receptors of the vascular smooth muscle cells and that prostacyclin plays a key role in such responses. Endothelium-dependent contractions are exacerbated when the production of nitric oxide is impaired (e.g. by oxidative stress, ageing, spontaneous hypertension and diabetes). They contribute to the blunting of endothelium-dependent vasodilatations in aged subjects and essential hypertensive and diabetic patients. In addition, recent data confirm that the release of endothelin-1 can contribute to endothelial dysfunction and that the peptide appears to be an important contributor to vascular dysfunction. Finally, it has become clear that nitric oxide itself, under certain conditions (e.g. hypoxia), can cause biased activation of soluble guanylyl cyclase leading to the production of cyclic inosine monophosphate (cIMP) rather than cGMP and hence causes contraction rather than relaxation of the underlying vascular smooth muscle.
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Affiliation(s)
- P. M. Vanhoutte
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy; Li Ka Shing Faculty of Medicine; The University of Hong Kong; Hong Kong City Hong Kong
| | - H. Shimokawa
- Department of Cardiovascular Medicine; Tohoku University; Sendai Japan
| | - M. Feletou
- Department of Cardiovascular Research; Institut de Recherches Servier; Suresnes France
| | - E. H. C. Tang
- State Key Laboratory of Pharmaceutical Biotechnology and Department of Pharmacology and Pharmacy; Li Ka Shing Faculty of Medicine; The University of Hong Kong; Hong Kong City Hong Kong
- School of Biomedical Sciences; Li Ka Shing Faculty of Medicine; The University of Hong Kong; Hong Kong City Hong Kong
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26
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Sweat RS, Sloas DC, Stewart SA, Czarny-Ratajczak M, Baddoo M, Eastwood JR, Suarez-Martinez AD, Azimi MS, Burks HE, Chedister LO, Myers L, Murfee WL. Aging is associated with impaired angiogenesis, but normal microvascular network structure, in the rat mesentery. Am J Physiol Heart Circ Physiol 2016; 312:H275-H284. [PMID: 27864233 DOI: 10.1152/ajpheart.00200.2016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 10/04/2016] [Accepted: 10/20/2016] [Indexed: 01/22/2023]
Abstract
A big problem associated with aging is thought to be impaired microvascular growth or angiogenesis. However, to link the evidence for impaired angiogenesis to microvascular dysfunction in aged tissues, we must compare adult vs. aged microvascular networks in unstimulated scenarios. The objective of this study was to test the hypothesis that aged microvascular networks are characterized by both fewer vessels and the impaired ability to undergo angiogenesis. Mesentery tissues from adult (9-mo) and aged (24-mo) male Fischer 344 rats were harvested and immunolabeled for platelet/endothelial cell adhesion molecule (an endothelial cell marker) according to two scenarios: unstimulated and stimulated. For unstimulated groups, tissues harvested from adult and aged rats were compared. For stimulated groups, tissues were harvested 3 or 10 days after compound 48/80-induced mast cell degranulation stimulation. Unstimulated aged microvascular networks displayed larger mean vascular area per tissue area compared with the unstimulated adult networks. The lack of a decrease in vessel density was supported at the gene expression level with RNA-Seq analysis and with comparison of vessel densities in soleus muscle. Following stimulation, capillary sprouting and vessel density were impaired in aged networks at 3 and 10 days, respectively. Our results suggest that aging associated with impaired angiogenesis mechanisms might not influence normal microvascular function, since unstimulated aged microvascular networks can display a "normal adult-like" vessel density and architecture. NEW & NOTEWORTHY Using a multidimensional approach, we present evidence supporting that aged microvascular networks display vessel density and patterning similar to adult networks despite also being characterized by a decreased capacity to undergo angiogenesis. Thus, vessel loss is not necessarily a characteristic of aging.
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Affiliation(s)
- Richard S Sweat
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | - David C Sloas
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | - Scott A Stewart
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | | | - Melody Baddoo
- Tulane Cancer Center, Tulane University School of Medicine, New Orleans, Louisiana.,Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana; and
| | - James R Eastwood
- Tulane Center for Aging, Tulane University School of Medicine, New Orleans, Louisiana
| | | | - Mohammad S Azimi
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | - Hope E Burks
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | - Lee O Chedister
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana
| | - Leann Myers
- Department of Biostatistics and Bioinformatics, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Walter L Murfee
- Department of Biomedical Engineering, Tulane University, New Orleans, Louisiana;
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Sesti F. Oxidation of K(+) Channels in Aging and Neurodegeneration. Aging Dis 2016; 7:130-5. [PMID: 27114846 PMCID: PMC4809605 DOI: 10.14336/ad.2015.0901] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 09/01/2015] [Indexed: 01/26/2023] Open
Abstract
Reversible regulation of proteins by reactive oxygen species (ROS) is an important mechanism of neuronal plasticity. In particular, ROS have been shown to act as modulatory molecules of ion channels-which are key to neuronal excitability-in several physiological processes. However ROS are also fundamental contributors to aging vulnerability. When the level of excess ROS increases in the cell during aging, DNA is damaged, proteins are oxidized, lipids are degraded and more ROS are produced, all culminating in significant cell injury. From this arose the idea that oxidation of ion channels by ROS is one of the culprits for neuronal aging. Aging-dependent oxidative modification of voltage-gated potassium (K(+)) channels was initially demonstrated in the nematode Caenorhabditis elegans and more recently in the mammalian brain. Specifically, oxidation of the delayed rectifier KCNB1 (Kv2.1) and of Ca(2+)- and voltage sensitive K(+) channels have been established suggesting that their redox sensitivity contributes to altered excitability, progression of healthy aging and of neurodegenerative disease. Here I discuss the implications that oxidation of K(+) channels by ROS may have for normal aging, as well as for neurodegenerative disease.
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Affiliation(s)
- Federico Sesti
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ 08854, USA
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Patel R, Sesti F. Oxidation of ion channels in the aging nervous system. Brain Res 2016; 1639:174-85. [PMID: 26947620 DOI: 10.1016/j.brainres.2016.02.046] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2015] [Revised: 02/24/2016] [Accepted: 02/25/2016] [Indexed: 12/19/2022]
Abstract
Ion channels are integral membrane proteins that allow passive diffusion of ions across membranes. In neurons and in other excitable cells, the harmonious coordination between the numerous types of ion channels shape and propagate electrical signals. Increased accumulation of reactive oxidative species (ROS), and subsequent oxidation of proteins, including ion channels, is a hallmark feature of aging and may contribute to cell failure as a result. In this review we discuss the effects of ROS on three major types of ion channels of the central nervous system, namely the potassium (K(+)), calcium (Ca(2+)) and sodium (Na(+)) channels. We examine two general mechanisms through which ROS affect ion channels: via direct oxidation of specific residues and via indirect interference of pathways that regulate the channels. The overall status of the present studies indicates that the interaction of ion channels with ROS is multimodal and pervasive in the central nervous system and likely constitutes a general mechanism of aging susceptibility.
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Affiliation(s)
- Rahul Patel
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers University, 683 Hoes Lane West, Piscataway, NJ 08854, USA
| | - Federico Sesti
- Department of Neuroscience and Cell Biology, Robert Wood Johnson Medical School, Rutgers University, 683 Hoes Lane West, Piscataway, NJ 08854, USA.
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Change in vascular smooth muscle response to 5-HT due to short- or long-term endothelial denudation of the bovine digital vein. Vet J 2016; 207:154-159. [DOI: 10.1016/j.tvjl.2015.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 09/27/2015] [Accepted: 10/04/2015] [Indexed: 11/19/2022]
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Bentov I, Reed MJ. The effect of aging on the cutaneous microvasculature. Microvasc Res 2015; 100:25-31. [PMID: 25917013 PMCID: PMC4461519 DOI: 10.1016/j.mvr.2015.04.004] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Revised: 03/27/2015] [Accepted: 04/17/2015] [Indexed: 01/12/2023]
Abstract
Aging is associated with a progressive loss of function in all organs. Under normal conditions the physiologic compensation for age-related deficits is sufficient, but during times of stress the limitations of this reserve become evident. Explanations for this reduction in reserve include the changes in the microcirculation that occur during the normal aging process. The microcirculation is defined as the blood flow through arterioles, capillaries and venules, which are the smallest vessels in the vasculature and are embedded within organs and tissues. Optimal strategies to maintain the microvasculature following surgery and other stressors must use multifactorial approaches. Using skin as the model organ, we will review the anatomical and functional changes in the microcirculation with aging, and some of the available clinical strategies to potentially mitigate the effect of these changes on important clinical outcomes.
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Affiliation(s)
- Itay Bentov
- Department of Anesthesiology and Pain Medicine, Harborview Medical Center, University of Washington, Seattle, USA.
| | - May J Reed
- Division of Gerontology and Geriatric Medicine, Department of Medicine, Harborview Medical Center, University of Washington, Seattle, USA
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Pries AR, Badimon L, Bugiardini R, Camici PG, Dorobantu M, Duncker DJ, Escaned J, Koller A, Piek JJ, de Wit C. Coronary vascular regulation, remodelling, and collateralization: mechanisms and clinical implications on behalf of the working group on coronary pathophysiology and microcirculation. Eur Heart J 2015; 36:3134-46. [DOI: 10.1093/eurheartj/ehv100] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 03/13/2015] [Indexed: 12/31/2022] Open
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SK channels and ventricular arrhythmias in heart failure. Trends Cardiovasc Med 2015; 25:508-14. [PMID: 25743622 DOI: 10.1016/j.tcm.2015.01.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 01/19/2015] [Accepted: 01/20/2015] [Indexed: 12/18/2022]
Abstract
Small-conductance Ca(2+)-activated K(+) (SK) currents are important in the repolarization of normal atrial (but not ventricular) cardiomyocytes. However, recent studies showed that the SK currents are upregulated in failing ventricular cardiomyocytes, along with increased SK channel protein expression and enhanced sensitivity to intracellular Ca(2+). The SK channel activation may be either anti-arrhythmic or pro-arrhythmic, depending on the underlying clinical situations. While the SK channel is a new target of anti-arrhythmic therapy, drug safety is still one of the major concerns.
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Reverri EJ, Morrissey BM, Cross CE, Steinberg FM. Inflammation, oxidative stress, and cardiovascular disease risk factors in adults with cystic fibrosis. Free Radic Biol Med 2014; 76:261-77. [PMID: 25172163 DOI: 10.1016/j.freeradbiomed.2014.08.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 07/31/2014] [Accepted: 08/05/2014] [Indexed: 12/21/2022]
Abstract
Cystic fibrosis (CF) represents one of a number of localized lung and non-lung diseases with an intense chronic inflammatory component associated with evidence of systemic oxidative stress. Many of these chronic inflammatory diseases are accompanied by an array of atherosclerotic processes and cardiovascular disease (CVD), another condition strongly related to inflammation and oxidative stress. As a consequence of a dramatic increase in long-lived patients with CF in recent decades, the specter of CVD must be considered in these patients who are now reaching middle age and beyond. Buttressed by recent data documenting that CF patients exhibit evidence of endothelial dysfunction, a recognized precursor of atherosclerosis and CVD, the spectrum of risk factors for CVD in CF is reviewed here. Epidemiological data further characterizing the presence and extent of atherogenic processes in CF patients would seem important to obtain. Such studies should further inform and offer mechanistic insights into how other chronic inflammatory diseases potentiate the processes leading to CVDs.
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Affiliation(s)
- Elizabeth J Reverri
- Department of Nutrition, University of California Davis, One Shields Avenue, 3135 Meyer Hall, Davis, CA 95616, USA
| | - Brian M Morrissey
- Adult Cystic Fibrosis Clinic and Division of Pulmonary-Critical Care Medicine, University of California Davis Medical Center, 4150 V Street, Sacramento, CA 95817, USA
| | - Carroll E Cross
- Adult Cystic Fibrosis Clinic and Division of Pulmonary-Critical Care Medicine, University of California Davis Medical Center, 4150 V Street, Sacramento, CA 95817, USA.
| | - Francene M Steinberg
- Department of Nutrition, University of California Davis, One Shields Avenue, 3135 Meyer Hall, Davis, CA 95616, USA
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