1
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Peixoto-Neves D, Jaggar JH. Physiological functions and pathological involvement of ion channel trafficking in the vasculature. J Physiol 2023:10.1113/JP285007. [PMID: 37818949 PMCID: PMC11006830 DOI: 10.1113/jp285007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 09/28/2023] [Indexed: 10/13/2023] Open
Abstract
A variety of ion channels regulate membrane potential and calcium influx in arterial smooth muscle and endothelial cells to modify vascular functions, including contractility. The current (I) generated by a population of ion channels is equally dependent upon their number (N), open probability (Po) and single channel current (i), such that I = N.PO .i. A conventional view had been that ion channels traffic to the plasma membrane in a passive manner, resulting in a static surface population. It was also considered that channels assemble with auxiliary subunits prior to anterograde trafficking of the multimeric complex to the plasma membrane. Recent studies have demonstrated that physiological stimuli can regulate the surface abundance (N) of several different ion channels in arterial smooth muscle and endothelial cells to control arterial contractility. Physiological stimuli can also regulate the number of auxiliary subunits present in the plasma membrane to modify the biophysical properties, regulatory mechanisms and physiological functions of some ion channels. Furthermore, ion channel trafficking becomes dysfunctional in the vasculature during hypertension, which negatively impacts the regulation of contractility. The temporal kinetics of ion channel and auxiliary subunit trafficking can also vary depending on the signalling mechanisms and proteins involved. This review will summarize recent work that has uncovered the mechanisms, functions and pathological modifications of ion channel trafficking in arterial smooth muscle and endothelial cells.
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Affiliation(s)
| | - Jonathan H. Jaggar
- Department of Physiology, University of Tennessee Health Science Center, Memphis TN 38139
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2
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Pereira da Silva EA, Martín-Aragón Baudel M, Navedo MF, Nieves-Cintrón M. Ion channel molecular complexes in vascular smooth muscle. Front Physiol 2022; 13:999369. [PMID: 36091375 PMCID: PMC9459047 DOI: 10.3389/fphys.2022.999369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Accepted: 08/02/2022] [Indexed: 11/30/2022] Open
Abstract
Ion channels that influence membrane potential and intracellular calcium concentration control vascular smooth muscle excitability. Voltage-gated calcium channels (VGCC), transient receptor potential (TRP) channels, voltage (KV), and Ca2+-activated K+ (BK) channels are key regulators of vascular smooth muscle excitability and contractility. These channels are regulated by various signaling cues, including protein kinases and phosphatases. The effects of these ubiquitous signaling molecules often depend on the formation of macromolecular complexes that provide a platform for targeting and compartmentalizing signaling events to specific substrates. This manuscript summarizes our current understanding of specific molecular complexes involving VGCC, TRP, and KV and BK channels and their contribution to regulating vascular physiology.
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3
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Diversification of Potassium Currents in Excitable Cells via Kvβ Proteins. Cells 2022; 11:cells11142230. [PMID: 35883673 PMCID: PMC9317154 DOI: 10.3390/cells11142230] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Revised: 07/09/2022] [Accepted: 07/12/2022] [Indexed: 12/10/2022] Open
Abstract
Excitable cells of the nervous and cardiovascular systems depend on an assortment of plasmalemmal potassium channels to control diverse cellular functions. Voltage-gated potassium (Kv) channels are central to the feedback control of membrane excitability in these processes due to their activation by depolarized membrane potentials permitting K+ efflux. Accordingly, Kv currents are differentially controlled not only by numerous cellular signaling paradigms that influence channel abundance and shape voltage sensitivity, but also by heteromeric configurations of channel complexes. In this context, we discuss the current knowledge related to how intracellular Kvβ proteins interacting with pore complexes of Shaker-related Kv1 channels may establish a modifiable link between excitability and metabolic state. Past studies in heterologous systems have indicated roles for Kvβ proteins in regulating channel stability, trafficking, subcellular targeting, and gating. More recent works identifying potential in vivo physiologic roles are considered in light of these earlier studies and key gaps in knowledge to be addressed by future research are described.
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4
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Roig SR, Cassinelli S, Zeug A, Ponimaskin E, Felipe A. Oligomerization and Spatial Distribution of Kvβ1.1 and Kvβ2.1 Regulatory Subunits. Front Physiol 2022; 13:930769. [PMID: 35784882 PMCID: PMC9247503 DOI: 10.3389/fphys.2022.930769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 06/02/2022] [Indexed: 11/13/2022] Open
Abstract
Members of the regulatory Kvβ family modulate the kinetics and traffic of voltage-dependent K+ (Kv) channels. The crystal structure of Kv channels associated with Kvβ peptides suggests a α4/β4 composition. Although Kvβ2 and Kvβ1 form heteromers, evidence supports that only Kvβ2.1 forms tetramers in the absence of α subunits. Therefore, the stoichiometry of the Kvβ oligomers fine-tunes the activity of hetero-oligomeric Kv channel complexes. We demonstrate that Kvβ subtypes form homo- and heterotetramers with similar affinities. The Kvβ1.1/Kvβ2.1 heteromer showed an altered spatial distribution in lipid rafts, recapitulating the Kvβ1.1 pattern. Because Kvβ2 is an active partner of the Kv1.3-TCR complex at the immunological synapse (IS), an association with Kvβ1 would alter this location, shaping the immune response. Differential regulation of Kvβs influences the traffic and architecture of the Kvβ heterotetramer, modulating Kvβ-dependent physiological responses.
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Affiliation(s)
- Sara R. Roig
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- Imaging Core Facility, Biozentrum, University of Basel, Basel, Switzerland
| | - Silvia Cassinelli
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
| | - Andre Zeug
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Evgeni Ponimaskin
- Department of Cellular Neurophysiology, Hannover Medical School, Hannover, Germany
| | - Antonio Felipe
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Barcelona, Spain
- *Correspondence: Antonio Felipe,
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5
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Pyridine nucleotide redox potential in coronary smooth muscle couples myocardial blood flow to cardiac metabolism. Nat Commun 2022; 13:2051. [PMID: 35440632 PMCID: PMC9018695 DOI: 10.1038/s41467-022-29745-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 03/28/2022] [Indexed: 12/13/2022] Open
Abstract
Adequate oxygen delivery to the heart during stress is essential for sustaining cardiac function. Acute increases in myocardial oxygen demand evoke coronary vasodilation and enhance perfusion via functional upregulation of smooth muscle voltage-gated K+ (Kv) channels. Because this response is controlled by Kv1 accessory subunits (i.e., Kvβ), which are NAD(P)(H)-dependent aldo-keto reductases, we tested the hypothesis that oxygen demand modifies arterial [NAD(H)]i, and that resultant cytosolic pyridine nucleotide redox state influences Kv1 activity. High-resolution imaging mass spectrometry and live-cell imaging reveal cardiac workload-dependent increases in NADH:NAD+ in intramyocardial arterial myocytes. Intracellular NAD(P)(H) redox ratios reflecting elevated oxygen demand potentiate native coronary Kv1 activity in a Kvβ2-dependent manner. Ablation of Kvβ2 catalysis suppresses redox-dependent increases in Kv1 activity, vasodilation, and the relationship between cardiac workload and myocardial blood flow. Collectively, this work suggests that the pyridine nucleotide sensitivity and enzymatic activity of Kvβ2 controls coronary vasoreactivity and myocardial blood flow during metabolic stress. Physiological matching of blood flow to the demand for oxygen by the heart is required for sustained cardiac health, yet the underlying mechanisms are obscure. Here, the authors report a key role for acute modifications to the redox state of intracellular pyridine nucleotides in coronary smooth muscle and their impact on voltage-gated K + channels in metabolic vasodilation
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6
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Jackson WF. Another Piece of the Puzzle: Voltage-Gated K + Channel β2-Subunits as a Coronary Vascular Smooth Muscle Sensor of Cardiac Work. Circ Res 2021; 128:752-754. [PMID: 33734818 DOI: 10.1161/circresaha.121.318953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, MI
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7
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Ohanyan V, Raph SM, Dwenger MM, Hu X, Pucci T, Mack G, Moore JB, Chilian WM, Bhatnagar A, Nystoriak MA. Myocardial Blood Flow Control by Oxygen Sensing Vascular Kvβ Proteins. Circ Res 2021; 128:738-751. [PMID: 33499656 DOI: 10.1161/circresaha.120.317715] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Vahagn Ohanyan
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown (V.O., T.P., G.M., W.M.C.)
| | - Sean M Raph
- Division of Environmental Medicine, Department of Medicine, Diabetes and Obesity Center, University of Louisville, KY (S.M.R., M.M.D., X.H., J.B.M., A.B., M.A.N.)
| | - Marc M Dwenger
- Division of Environmental Medicine, Department of Medicine, Diabetes and Obesity Center, University of Louisville, KY (S.M.R., M.M.D., X.H., J.B.M., A.B., M.A.N.)
| | - Xuemei Hu
- Division of Environmental Medicine, Department of Medicine, Diabetes and Obesity Center, University of Louisville, KY (S.M.R., M.M.D., X.H., J.B.M., A.B., M.A.N.)
| | - Thomas Pucci
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown (V.O., T.P., G.M., W.M.C.)
| | - Gregory Mack
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown (V.O., T.P., G.M., W.M.C.)
| | - Joseph B Moore
- Division of Environmental Medicine, Department of Medicine, Diabetes and Obesity Center, University of Louisville, KY (S.M.R., M.M.D., X.H., J.B.M., A.B., M.A.N.)
| | - William M Chilian
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown (V.O., T.P., G.M., W.M.C.)
| | - Aruni Bhatnagar
- Division of Environmental Medicine, Department of Medicine, Diabetes and Obesity Center, University of Louisville, KY (S.M.R., M.M.D., X.H., J.B.M., A.B., M.A.N.)
| | - Matthew A Nystoriak
- Division of Environmental Medicine, Department of Medicine, Diabetes and Obesity Center, University of Louisville, KY (S.M.R., M.M.D., X.H., J.B.M., A.B., M.A.N.)
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8
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Metabolic regulation of Kv channels and cardiac repolarization by Kvβ2 subunits. J Mol Cell Cardiol 2019; 137:93-106. [PMID: 31639389 DOI: 10.1016/j.yjmcc.2019.09.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 09/24/2019] [Accepted: 09/28/2019] [Indexed: 11/21/2022]
Abstract
Voltage-gated potassium (Kv) channels control myocardial repolarization. Pore-forming Kvα proteins associate with intracellular Kvβ subunits, which bind pyridine nucleotides with high affinity and differentially regulate channel trafficking, plasmalemmal localization and gating properties. Nevertheless, it is unclear how Kvβ subunits regulate myocardial K+ currents and repolarization. Here, we tested the hypothesis that Kvβ2 subunits regulate the expression of myocardial Kv channels and confer redox sensitivity to Kv current and cardiac repolarization. Co-immunoprecipitation and in situ proximity ligation showed that in cardiac myocytes, Kvβ2 interacts with Kv1.4, Kv1.5, Kv4.2, and Kv4.3. Cardiac myocytes from mice lacking Kcnab2 (Kvβ2-/-) had smaller cross sectional areas, reduced sarcolemmal abundance of Kvα binding partners, reduced Ito, IK,slow1, and IK,slow2 densities, and prolonged action potential duration compared with myocytes from wild type mice. These differences in Kvβ2-/- mice were associated with greater P wave duration and QT interval in electrocardiograms, and lower ejection fraction, fractional shortening, and left ventricular mass in echocardiographic and morphological assessments. Direct intracellular dialysis with a high NAD(P)H:NAD(P)+ accelerated Kv inactivation in wild type, but not Kvβ2-/- myocytes. Furthermore, elevated extracellular levels of lactate increased [NADH]i and prolonged action potential duration in wild type cardiac myocytes and perfused wild type, but not Kvβ2-/-, hearts. Taken together, these results suggest that Kvβ2 regulates myocardial electrical activity by supporting the functional expression of proteins that generate Ito and IK,slow, and imparting redox and metabolic sensitivity to Kv channels, thereby coupling cardiac repolarization to myocyte metabolism.
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9
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Haworth AS, Brackenbury WJ. Emerging roles for multifunctional ion channel auxiliary subunits in cancer. Cell Calcium 2019; 80:125-140. [PMID: 31071485 PMCID: PMC6553682 DOI: 10.1016/j.ceca.2019.04.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 04/16/2019] [Accepted: 04/16/2019] [Indexed: 02/07/2023]
Abstract
Several superfamilies of plasma membrane channels which regulate transmembrane ion flux have also been shown to regulate a multitude of cellular processes, including proliferation and migration. Ion channels are typically multimeric complexes consisting of conducting subunits and auxiliary, non-conducting subunits. Auxiliary subunits modulate the function of conducting subunits and have putative non-conducting roles, further expanding the repertoire of cellular processes governed by ion channel complexes to processes such as transcellular adhesion and gene transcription. Given this expansive influence of ion channels on cellular behaviour it is perhaps no surprise that aberrant ion channel expression is a common occurrence in cancer. This review will focus on the conducting and non-conducting roles of the auxiliary subunits of various Ca2+, K+, Na+ and Cl- channels and the burgeoning evidence linking such auxiliary subunits to cancer. Several subunits are upregulated (e.g. Cavβ, Cavγ) and downregulated (e.g. Kvβ) in cancer, while other subunits have been functionally implicated as oncogenes (e.g. Navβ1, Cavα2δ1) and tumour suppressor genes (e.g. CLCA2, KCNE2, BKγ1) based on in vivo studies. The strengthening link between ion channel auxiliary subunits and cancer has exposed these subunits as potential biomarkers and therapeutic targets. However further mechanistic understanding is required into how these subunits contribute to tumour progression before their therapeutic potential can be fully realised.
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Affiliation(s)
- Alexander S Haworth
- Department of Biology, University of York, Heslington, York, YO10 5DD, UK; York Biomedical Research Institute, University of York, Heslington, York, YO10 5DD, UK
| | - William J Brackenbury
- Department of Biology, University of York, Heslington, York, YO10 5DD, UK; York Biomedical Research Institute, University of York, Heslington, York, YO10 5DD, UK.
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10
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Raph SM, Bhatnagar A, Nystoriak MA. Biochemical and physiological properties of K + channel-associated AKR6A (Kvβ) proteins. Chem Biol Interact 2019; 305:21-27. [PMID: 30926318 DOI: 10.1016/j.cbi.2019.03.023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 03/14/2019] [Accepted: 03/25/2019] [Indexed: 11/16/2022]
Abstract
Voltage-gated potassium (Kv) channels play an essential role in the regulation of membrane excitability and thereby control physiological processes such as cardiac excitability, neural communication, muscle contraction, and hormone secretion. Members of the Kv1 and Kv4 families are known to associate with auxiliary intracellular Kvβ subunits, which belong to the aldo-keto reductase superfamily. Electrophysiological studies have shown that these proteins regulate the gating properties of Kv channels. Although the three gene products encoding Kvβ proteins are functional enzymes in that they catalyze the nicotinamide adenine dinucleotide phosphate (NAD[P]H)-dependent reduction of a wide range of aldehyde and ketone substrates, the physiological role for these proteins and how each subtype may perform unique roles in coupling membrane excitability with cellular metabolic processes remains unclear. Here, we discuss current knowledge of the enzymatic properties of Kvβ proteins from biochemical studies with their described and purported physiological and pathophysiological influences.
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Affiliation(s)
- Sean M Raph
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA
| | - Aruni Bhatnagar
- Department of Medicine, Diabetes and Obesity Center, University of Louisville, Louisville, KY, 40202, USA
| | - Matthew A Nystoriak
- Department of Medicine, Diabetes and Obesity Center, University of Louisville, Louisville, KY, 40202, USA.
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11
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Capera J, Serrano-Novillo C, Navarro-Pérez M, Cassinelli S, Felipe A. The Potassium Channel Odyssey: Mechanisms of Traffic and Membrane Arrangement. Int J Mol Sci 2019; 20:ijms20030734. [PMID: 30744118 PMCID: PMC6386995 DOI: 10.3390/ijms20030734] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/06/2019] [Accepted: 02/08/2019] [Indexed: 12/29/2022] Open
Abstract
Ion channels are transmembrane proteins that conduct specific ions across biological membranes. Ion channels are present at the onset of many cellular processes, and their malfunction triggers severe pathologies. Potassium channels (KChs) share a highly conserved signature that is necessary to conduct K⁺ through the pore region. To be functional, KChs require an exquisite regulation of their subcellular location and abundance. A wide repertoire of signatures facilitates the proper targeting of the channel, fine-tuning the balance that determines traffic and location. These signature motifs can be part of the secondary or tertiary structure of the protein and are spread throughout the entire sequence. Furthermore, the association of the pore-forming subunits with different ancillary proteins forms functional complexes. These partners can modulate traffic and activity by adding their own signatures as well as by exposing or masking the existing ones. Post-translational modifications (PTMs) add a further dimension to traffic regulation. Therefore, the fate of a KCh is not fully dependent on a gene sequence but on the balance of many other factors regulating traffic. In this review, we assemble recent evidence contributing to our understanding of the spatial expression of KChs in mammalian cells. We compile specific signatures, PTMs, and associations that govern the destination of a functional channel.
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Affiliation(s)
- Jesusa Capera
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain.
| | - Clara Serrano-Novillo
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain.
| | - María Navarro-Pérez
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain.
| | - Silvia Cassinelli
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain.
| | - Antonio Felipe
- Molecular Physiology Laboratory, Departament de Bioquímica i Biomedicina Molecular, Institut de Biomedicina (IBUB), Universitat de Barcelona, Avda. Diagonal 643, 08028 Barcelona, Spain.
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12
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Jackson WF. K V channels and the regulation of vascular smooth muscle tone. Microcirculation 2018; 25. [PMID: 28985443 DOI: 10.1111/micc.12421] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/01/2017] [Indexed: 12/31/2022]
Abstract
VSMCs in resistance arteries and arterioles express a diverse array of KV channels with members of the KV 1, KV 2 and KV 7 families being particularly important. Members of the KV channel family: (i) are highly expressed in VSMCs; (ii) are active at the resting membrane potential of VSMCs in vivo (-45 to -30 mV); (iii) contribute to the negative feedback regulation of VSMC membrane potential and myogenic tone; (iv) are activated by cAMP-related vasodilators, hydrogen sulfide and hydrogen peroxide; (v) are inhibited by increases in intracellular Ca2+ and vasoconstrictors that signal through Gq -coupled receptors; (vi) are involved in the proliferative phenotype of VSMCs; and (vii) are modulated by diseases such as hypertension, obesity, the metabolic syndrome and diabetes. Thus, KV channels participate in every aspect of the regulation of VSMC function in both health and disease.
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Affiliation(s)
- William F Jackson
- Department of Pharmacology & Toxicology, Michigan State University, East Lansing, MI, USA
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13
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Dwenger MM, Ohanyan V, Navedo MF, Nystoriak MA. Coronary microvascular Kv1 channels as regulatory sensors of intracellular pyridine nucleotide redox potential. Microcirculation 2018; 25. [PMID: 29110409 DOI: 10.1111/micc.12426] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 10/30/2017] [Indexed: 12/16/2022]
Abstract
Smooth muscle voltage-gated potassium (Kv) channels are important regulators of microvascular tone and tissue perfusion. Recent studies indicate that Kv1 channels represent a key component of the physiological coupling between coronary blood flow and myocardial oxygen demand. While the mechanisms by which metabolic changes in the heart are transduced to alter coronary Kv1 channel gating and promote vasodilation are unclear, a growing body of evidence underscores a pivotal role of Kv1 channels in sensing the cellular redox status. Here, we discuss current knowledge of mechanisms of Kv channel redox regulation with respect to pyridine nucleotide modulation of Kv1 function via ancillary Kvβ proteins as well as direct modulation of channel activity via reactive oxygen and nitrogen species. We identify areas of additional research to address the integration of regulatory processes under altered physiological and pathophysiological conditions that may reveal insights into novel treatment strategies for conditions in which the matching of coronary blood supply and myocardial oxygen demand is compromised.
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Affiliation(s)
- Marc M Dwenger
- Diabetes and Obesity Center, Institute of Molecular Cardiology, Department of Medicine, University of Louisville, Louisville, KY, USA
| | - Vahagn Ohanyan
- Department of Integrative Medical Sciences, Northeast Ohio Medical University, Rootstown, OH, USA
| | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, CA, USA
| | - Matthew A Nystoriak
- Diabetes and Obesity Center, Institute of Molecular Cardiology, Department of Medicine, University of Louisville, Louisville, KY, USA
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14
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Nieves-Cintrón M, Syed AU, Nystoriak MA, Navedo MF. Regulation of voltage-gated potassium channels in vascular smooth muscle during hypertension and metabolic disorders. Microcirculation 2018; 25:10.1111/micc.12423. [PMID: 29044853 PMCID: PMC5760350 DOI: 10.1111/micc.12423] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/11/2017] [Indexed: 12/12/2022]
Abstract
Voltage-gated potassium (KV ) channels are key regulators of vascular smooth muscle contractility and vascular tone, and thus have major influence on the microcirculation. KV channels are important determinants of vascular smooth muscle membrane potential (Em ). A number of KV subunits are expressed in the plasma membrane of smooth muscle cells. Each subunit confers distinct kinetics and regulatory properties that allow for fine control of Em to orchestrate vascular tone. Modifications in KV subunit expression and/or channel activity can contribute to changes in vascular smooth muscle contractility in response to different stimuli and in diverse pathological conditions. Consistent with this, a number of studies suggest alterations in KV subunit expression and/or function as underlying contributing mechanisms for small resistance artery dysfunction in pathologies such as hypertension and metabolic disorders, including diabetes. Here, we review our current knowledge on the effects of these pathologies on KV channel expression and function in vascular smooth muscle cells, and the repercussions on (micro)vascular function.
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Affiliation(s)
| | - Arsalan U. Syed
- Department of Pharmacology, University of California, Davis, CA 95616
| | - Matthew A. Nystoriak
- Diabetes and Obesity Center, Department of Medicine, University of Louisville, Louisville, KY 40202
| | - Manuel F. Navedo
- Department of Pharmacology, University of California, Davis, CA 95616
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