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He Z, Xie L, Liu J, Wei X, Zhang W, Mei Z. Novel insight into the role of A-kinase anchoring proteins (AKAPs) in ischemic stroke and therapeutic potentials. Biomed Pharmacother 2024; 175:116715. [PMID: 38739993 DOI: 10.1016/j.biopha.2024.116715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 05/03/2024] [Accepted: 05/06/2024] [Indexed: 05/16/2024] Open
Abstract
Ischemic stroke, a devastating disease associated with high mortality and disability worldwide, has emerged as an urgent public health issue. A-kinase anchoring proteins (AKAPs) are a group of signal-organizing molecules that compartmentalize and anchor a wide range of receptors and effector proteins and have a major role in stabilizing mitochondrial function and promoting neurodevelopmental development in the central nervous system (CNS). Growing evidence suggests that dysregulation of AKAPs expression and activity is closely associated with oxidative stress, ion disorder, mitochondrial dysfunction, and blood-brain barrier (BBB) impairment in ischemic stroke. However, the underlying mechanisms remain inadequately understood. This review provides a comprehensive overview of the composition and structure of A-kinase anchoring protein (AKAP) family members, emphasizing their physiological functions in the CNS. We explored in depth the molecular and cellular mechanisms of AKAP complexes in the pathological progression and risk factors of ischemic stroke, including hypertension, hyperglycemia, lipid metabolism disorders, and atrial fibrillation. Herein, we highlight the potential of AKAP complexes as a pharmacological target against ischemic stroke in the hope of inspiring translational research and innovative clinical approaches.
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Affiliation(s)
- Ziyu He
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Letian Xie
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Jiyong Liu
- Hunan Provincial Key Laboratory of Traditional Chinese Medicine Diagnostics, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Xuan Wei
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China
| | - Wenli Zhang
- School of Pharmacy, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China.
| | - Zhigang Mei
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-Cerebral Diseases, College of Integrated Traditional Chinese Medicine and Western Medicine, Hunan University of Chinese Medicine, Changsha, Hunan 410208, China; Third-Grade Pharmacological Laboratory on Chinese Medicine Approved by State Administration of Traditional Chinese Medicine, College of Medicine and Health Sciences, China Three Gorges University, Yichang, Hubei 443002, China.
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2
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Luft FC. Calcineurin inhibition, cardiovascular consequences, vascular resistance, and potential responses. Acta Physiol (Oxf) 2024; 240:e14084. [PMID: 38214031 DOI: 10.1111/apha.14084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/20/2023] [Accepted: 01/01/2024] [Indexed: 01/13/2024]
Abstract
AIM To place the consequences of calcineurin inhibition in a cardiovascular context. METHODS Literature review coupled with personal encounters. RESULTS Calcineurin is a calcium-binding and calmodulin-binding protein that is conserved across evolution from yeast to mammals. The enzyme functions as a calcium-dependent, calmodulin-stimulated protein phosphatase. Its role in regulating physiology has largely been elucidated by observing calcineurin inhibition. Calcineurin inhibition transformed organ transplantation from an experiment into a therapy and made much of general immunotherapy possible. The function of this phosphatase and how its inhibition leads to toxicity concern us to this date. Initial research from patients and animal models implicated a panoply of factors contributing to hypertension and vasculopathy. Subsequently, the role of calcineurin in regulating the effective fluid volume, sodium reabsorption, and potassium and hydrogen ion excretion was elucidated by investigating calcineurin inhibition. Understanding the regulatory effects of calcineurin on endothelial and vascular smooth muscle cell function has also made substantial progress. However, precisely how the increase in systemic vascular resistance arises requires further mechanistic research. CONCLUSION Calcineurin inhibition continues to save lives; however, options to counteract the negative effects of calcineurin inhibition should be vigorously pursued.
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Affiliation(s)
- Friedrich C Luft
- Experimental and Clinical Research Center, a cooperation between the Max-Delbrück Center for Molecular Medicine and the Charité Medical Faculty, Berlin, Germany
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3
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Hernandez-Hernandez G, O'Dwyer SC, Yang PC, Matsumoto C, Tieu M, Fong Z, Lewis TJ, Santana LF, Clancy CE. A computational model predicts sex-specific responses to calcium channel blockers in mammalian mesenteric vascular smooth muscle. eLife 2024; 12:RP90604. [PMID: 38335126 PMCID: PMC10942543 DOI: 10.7554/elife.90604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024] Open
Abstract
The function of the smooth muscle cells lining the walls of mammalian systemic arteries and arterioles is to regulate the diameter of the vessels to control blood flow and blood pressure. Here, we describe an in silico model, which we call the 'Hernandez-Hernandez model', of electrical and Ca2+ signaling in arterial myocytes based on new experimental data indicating sex-specific differences in male and female arterial myocytes from murine resistance arteries. The model suggests the fundamental ionic mechanisms underlying membrane potential and intracellular Ca2+ signaling during the development of myogenic tone in arterial blood vessels. Although experimental data suggest that KV1.5 channel currents have similar amplitudes, kinetics, and voltage dependencies in male and female myocytes, simulations suggest that the KV1.5 current is the dominant current regulating membrane potential in male myocytes. In female cells, which have larger KV2.1 channel expression and longer time constants for activation than male myocytes, predictions from simulated female myocytes suggest that KV2.1 plays a primary role in the control of membrane potential. Over the physiological range of membrane potentials, the gating of a small number of voltage-gated K+ channels and L-type Ca2+ channels are predicted to drive sex-specific differences in intracellular Ca2+ and excitability. We also show that in an idealized computational model of a vessel, female arterial smooth muscle exhibits heightened sensitivity to commonly used Ca2+ channel blockers compared to male. In summary, we present a new model framework to investigate the potential sex-specific impact of antihypertensive drugs.
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Affiliation(s)
| | - Samantha C O'Dwyer
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
| | - Pei-Chi Yang
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
| | - Collin Matsumoto
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
| | - Mindy Tieu
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
| | - Zhihui Fong
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
| | - Timothy J Lewis
- Department of Mathematics, University of California, DavisDavisUnited States
| | - L Fernando Santana
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
| | - Colleen E Clancy
- Department of Physiology & Membrane Biology, University of California, DavisDavisUnited States
- Center for Precision Medicine and Data Sciences, University of California, DavisDavisUnited States
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4
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Hernandez-Hernandez G, O’Dwyer SC, Matsumoto C, Tieu M, Fong Z, Yang PC, Lewis TJ, Fernando Santana L, Clancy CE. A computational model predicts sex-specific responses to calcium channel blockers in mammalian mesenteric vascular smooth muscle. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.06.24.546394. [PMID: 37425682 PMCID: PMC10327109 DOI: 10.1101/2023.06.24.546394] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
The function of the smooth muscle cells lining the walls of mammalian systemic arteries and arterioles is to regulate the diameter of the vessels to control blood flow and blood pressure. Here, we describe an in-silico model, which we call the "Hernandez-Hernandez model", of electrical and C a 2+ signaling in arterial myocytes based on new experimental data indicating sex-specific differences in male and female arterial myocytes from murine resistance arteries. The model suggests the fundamental ionic mechanisms underlying membrane potential and intracellular C a 2+ signaling during the development of myogenic tone in arterial blood vessels. Although experimental data suggest that KV1.5 channel currents have similar amplitudes, kinetics, and voltage dependencies in male and female myocytes, simulations suggest that the KV1.5 current is the dominant current regulating membrane potential in male myocytes. In female cells, which have larger KV2.1 channel expression and longer time constants for activation than male myocytes, predictions from simulated female myocytes suggest that KV2.1 plays a primary role in the control of membrane potential. Over the physiological range of membrane potentials, the gating of a small number of voltage-gated K+ channels and L-type C a 2+ channels are predicted to drive sex-specific differences in intracellular C a 2+ and excitability. We also show that in an idealized computational model of a vessel, female arterial smooth muscle exhibits heightened sensitivity to commonly used C a 2+ channel blockers compared to male. In summary, we present a new model framework to investigate the potential sex-specific impact of anti-hypertensive drugs.
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Affiliation(s)
- Gonzalo Hernandez-Hernandez
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
- Department of Mathematics, University of California, Davis, California, 95616
| | - Samantha C. O’Dwyer
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
- Department of Mathematics, University of California, Davis, California, 95616
| | - Collin Matsumoto
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
- Department of Mathematics, University of California, Davis, California, 95616
| | - Mindy Tieu
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
- Department of Mathematics, University of California, Davis, California, 95616
| | - Zhihui Fong
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
- Department of Mathematics, University of California, Davis, California, 95616
| | - Pei-Chi Yang
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
- Department of Mathematics, University of California, Davis, California, 95616
| | - Timothy J. Lewis
- Department of Mathematics, University of California, Davis, California, 95616
| | | | - Colleen E. Clancy
- Department of Physiology & Membrane Biology, Center for Precision Medicine and Data Science, University of California School of Medicine, Davis, California, 95616
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Matsumoto C, O'Dwyer SC, Manning D, Hernandez-Hernandez G, Rhana P, Fong Z, Sato D, Clancy CE, Vierra NC, Trimmer JS, Fernando Santana L. The formation of K V2.1 macro-clusters is required for sex-specific differences in L-type Ca V1.2 clustering and function in arterial myocytes. Commun Biol 2023; 6:1165. [PMID: 37963972 PMCID: PMC10645748 DOI: 10.1038/s42003-023-05527-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/31/2023] [Indexed: 11/16/2023] Open
Abstract
In arterial myocytes, the canonical function of voltage-gated CaV1.2 and KV2.1 channels is to induce myocyte contraction and relaxation through their responses to membrane depolarization, respectively. Paradoxically, KV2.1 also plays a sex-specific role by promoting the clustering and activity of CaV1.2 channels. However, the impact of KV2.1 protein organization on CaV1.2 function remains poorly understood. We discovered that KV2.1 forms micro-clusters, which can transform into large macro-clusters when a critical clustering site (S590) in the channel is phosphorylated in arterial myocytes. Notably, female myocytes exhibit greater phosphorylation of S590, and macro-cluster formation compared to males. Contrary to current models, the activity of KV2.1 channels seems unrelated to density or macro-clustering in arterial myocytes. Disrupting the KV2.1 clustering site (KV2.1S590A) eliminated KV2.1 macro-clustering and sex-specific differences in CaV1.2 cluster size and activity. We propose that the degree of KV2.1 clustering tunes CaV1.2 channel function in a sex-specific manner in arterial myocytes.
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Affiliation(s)
- Collin Matsumoto
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - Samantha C O'Dwyer
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - Declan Manning
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | | | - Paula Rhana
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - Zhihui Fong
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - Daisuke Sato
- Department of Pharmacology, School of Medicine, University of California, Davis, CA, USA
| | - Colleen E Clancy
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - Nicholas C Vierra
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - James S Trimmer
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA
| | - L Fernando Santana
- Department of Physiology and Membrane Biology, School of Medicine, University of California, Davis, CA, USA.
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6
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Yang Q, Perfitt TL, Quay J, Hu L, Lawson-Qureshi D, Colbran RJ. Clustering of Ca V 1.3 L-type calcium channels by Shank3. J Neurochem 2023; 167:16-37. [PMID: 37392026 PMCID: PMC10543641 DOI: 10.1111/jnc.15880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 05/19/2023] [Accepted: 05/28/2023] [Indexed: 07/02/2023]
Abstract
Clustering of L-type voltage-gated Ca2+ channels (LTCCs) in the plasma membrane is increasingly implicated in creating highly localized Ca2+ signaling nanodomains. For example, neuronal LTCC activation can increase phosphorylation of the nuclear CREB transcription factor by increasing Ca2+ concentrations within a nanodomain close to the channel, without requiring bulk Ca2+ increases in the cytosol or nucleus. However, the molecular basis for LTCC clustering is poorly understood. The postsynaptic scaffolding protein Shank3 specifically associates with one of the major neuronal LTCCs, the CaV 1.3 calcium channel, and is required for optimal LTCC-dependent excitation-transcription coupling. Here, we co-expressed CaV 1.3 α1 subunits with two distinct epitope-tags with or without Shank3 in HEK cells. Co-immunoprecipitation studies using the cell lysates revealed that Shank3 can assemble complexes containing multiple CaV 1.3 α1 subunits under basal conditions. Moreover, CaV 1.3 LTCC complex formation was facilitated by CaV β subunits (β3 and β2a), which also interact with Shank3. Shank3 interactions with CaV 1.3 LTCCs and multimeric CaV 1.3 LTCC complex assembly were disrupted following the addition of Ca2+ to cell lysates, perhaps simulating conditions within an activated CaV 1.3 LTCC nanodomain. In intact HEK293T cells, co-expression of Shank3 enhanced the intensity of membrane-localized CaV 1.3 LTCC clusters under basal conditions, but not after Ca2+ channel activation. Live cell imaging studies also revealed that Ca2+ influx through LTCCs disassociated Shank3 from CaV 1.3 LTCCs clusters and reduced the CaV 1.3 cluster intensity. Deletion of the Shank3 PDZ domain prevented both binding to CaV 1.3 and the changes in multimeric CaV 1.3 LTCC complex assembly in vitro and in HEK293 cells. Finally, we found that shRNA knock-down of Shank3 expression in cultured rat primary hippocampal neurons reduced the intensity of surface-localized CaV 1.3 LTCC clusters in dendrites. Taken together, our findings reveal a novel molecular mechanism contributing to neuronal LTCC clustering under basal conditions.
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Affiliation(s)
- Qian Yang
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
| | - Tyler L. Perfitt
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
- Current address: Rare Disease Research Unit, Pfizer Inc
| | - Juliana Quay
- Chemical and Physical Biology, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
| | - Lan Hu
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
| | - Dorian Lawson-Qureshi
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
| | - Roger J. Colbran
- Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
- Vanderbilt Brain Institute, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
- Vanderbilt-Kennedy Center for Research on Human Development, Vanderbilt University School of Medicine, Nashville, TN, USA 37232-0615
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7
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Matsumoto C, O'Dwyer SC, Manning D, Hernandez-Hernandez G, Rhana P, Fong Z, Sato D, Clancy CE, Vierra NC, Trimmer JS, Santana LF. The formation of K V 2.1 macro-clusters is required for sex-specific differences in L-type Ca V 1.2 clustering and function in arterial myocytes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.27.546725. [PMID: 37425816 PMCID: PMC10327069 DOI: 10.1101/2023.06.27.546725] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
In arterial myocytes, the canonical function of voltage-gated Ca V 1.2 and K V 2.1 channels is to induce myocyte contraction and relaxation through their responses to membrane depolarization, respectively. Paradoxically, K V 2.1 also plays a sex-specific role by promoting the clustering and activity of Ca V 1.2 channels. However, the impact of K V 2.1 protein organization on Ca V 1.2 function remains poorly understood. We discovered that K V 2.1 forms micro-clusters, which can transform into large macro-clusters when a critical clustering site (S590) in the channel is phosphorylated in arterial myocytes. Notably, female myocytes exhibit greater phosphorylation of S590, and macro-cluster formation compared to males. Contrary to current models, the activity of K V 2.1 channels seems unrelated to density or macro-clustering in arterial myocytes. Disrupting the K V 2.1 clustering site (K V 2.1 S590A ) eliminated K V 2.1 macro-clustering and sex-specific differences in Ca V 1.2 cluster size and activity. We propose that the degree of K V 2.1 clustering tunes Ca V 1.2 channel function in a sex-specific manner in arterial myocytes.
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8
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Collins KB, Scott JD. Phosphorylation, compartmentalization, and cardiac function. IUBMB Life 2023; 75:353-369. [PMID: 36177749 PMCID: PMC10049969 DOI: 10.1002/iub.2677] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/15/2022] [Indexed: 11/08/2022]
Abstract
Protein phosphorylation is a fundamental element of cell signaling. First discovered as a biochemical switch in glycogen metabolism, we now know that this posttranslational modification permeates all aspects of cellular behavior. In humans, over 540 protein kinases attach phosphate to acceptor amino acids, whereas around 160 phosphoprotein phosphatases remove phosphate to terminate signaling. Aberrant phosphorylation underlies disease, and kinase inhibitor drugs are increasingly used clinically as targeted therapies. Specificity in protein phosphorylation is achieved in part because kinases and phosphatases are spatially organized inside cells. A prototypic example is compartmentalization of the cyclic adenosine 3',5'-monophosphate (cAMP)-dependent protein kinase A through association with A-kinase anchoring proteins. This configuration creates autonomous signaling islands where the anchored kinase is constrained in proximity to activators, effectors, and selected substates. This article primarily focuses on A kinase anchoring protein (AKAP) signaling in the heart with an emphasis on anchoring proteins that spatiotemporally coordinate excitation-contraction coupling and hypertrophic responses.
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Affiliation(s)
- Kerrie B. Collins
- Department of Pharmacology, University of Washington, School of Medicine, 1959 NE Pacific Ave, Seattle WA, 98195
| | - John D. Scott
- Department of Pharmacology, University of Washington, School of Medicine, 1959 NE Pacific Ave, Seattle WA, 98195
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9
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Cui Y, Gollasch M, Kassmann M. Arterial myogenic response and aging. Ageing Res Rev 2023; 84:101813. [PMID: 36470339 DOI: 10.1016/j.arr.2022.101813] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 11/21/2022] [Accepted: 11/29/2022] [Indexed: 12/12/2022]
Abstract
The arterial myogenic response is an inherent property of resistance arteries. Myogenic tone is crucial for maintaining a relatively constant blood flow in response to changes in intraluminal pressure and protects delicate organs from excessive blood flow. Although this fundamental physiological phenomenon has been extensively studied, the underlying molecular mechanisms are largely unknown. Recent studies identified a crucial role of mechano-activated angiotensin II type 1 receptors (AT1R) in this process. The development of myogenic response is affected by aging. In this review, we summarize recent progress made to understand the role of AT1R and other mechanosensors in the control of arterial myogenic response. We discuss age-related alterations in myogenic response and possible underlying mechanisms and implications for healthy aging.
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Affiliation(s)
- Yingqiu Cui
- Charité - Universitätsmedizin Berlin, Experimental and Clinical Research Center (ECRC), a joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine (MDC), Lindenberger Weg 80, 13125 Berlin, Germany
| | - Maik Gollasch
- Department of Internal Medicine and Geriatrics, University Medicine Greifswald, Felix-Hausdorff-Straße 3, 17487 Greifswald, Germany
| | - Mario Kassmann
- Department of Internal Medicine and Geriatrics, University Medicine Greifswald, Felix-Hausdorff-Straße 3, 17487 Greifswald, Germany.
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Martín-Aragón Baudel M, Hong J, Hell JW, Nieves-Cintrón M, Navedo MF. Mechanisms of Vascular Ca V1.2 Channel Regulation During Diabetic Hyperglycemia. Handb Exp Pharmacol 2023; 279:41-58. [PMID: 36598607 DOI: 10.1007/164_2022_628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Diabetes is a leading cause of disability and mortality worldwide. A major underlying factor in diabetes is the excessive glucose levels in the bloodstream (e.g., hyperglycemia). Vascular complications directly result from this metabolic abnormality, leading to disabling and life-threatening conditions. Dysfunction of vascular smooth muscle cells is a well-recognized factor mediating vascular complications during diabetic hyperglycemia. The function of vascular smooth muscle cells is exquisitely controlled by different ion channels. Among the ion channels, the L-type CaV1.2 channel plays a key role as it is the main Ca2+ entry pathway regulating vascular smooth muscle contractile state. The activity of CaV1.2 channels in vascular smooth muscle is altered by diabetic hyperglycemia, which may contribute to vascular complications. In this chapter, we summarize the current understanding of the regulation of CaV1.2 channels in vascular smooth muscle by different signaling pathways. We place special attention on the regulation of CaV1.2 channel activity in vascular smooth muscle by a newly uncovered AKAP5/P2Y11/AC5/PKA/CaV1.2 axis that is engaged during diabetic hyperglycemia. We further describe the pathophysiological implications of activation of this axis as it relates to myogenic tone and vascular reactivity and propose that this complex may be targeted for developing therapies to treat diabetic vascular complications.
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Affiliation(s)
| | - Junyoung Hong
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California Davis, Davis, CA, USA
| | | | - Manuel F Navedo
- Department of Pharmacology, University of California Davis, Davis, CA, USA.
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11
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Vascular Ca V1.2 channels in diabetes. CURRENT TOPICS IN MEMBRANES 2022; 90:65-93. [PMID: 36368875 DOI: 10.1016/bs.ctm.2022.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Diabetic vasculopathy is a significant cause of morbidity and mortality in the diabetic population. Hyperglycemia, one of the central metabolic abnormalities in diabetes, has been associated with vascular dysfunction due to endothelial cell damage. However, studies also point toward vascular smooth muscle as a locus for hyperglycemia-induced vascular dysfunction. Emerging evidence implicates hyperglycemia-induced regulation of vascular L-type Ca2+ channels CaV1.2 as a potential mechanism for vascular dysfunction during diabetes. This chapter summarizes our current understanding of vascular CaV1.2 channels and their regulation during physiological and hyperglycemia/diabetes conditions. We will emphasize the role of CaV1.2 in vascular smooth muscle, the effects of elevated glucose on CaV1.2 function, and the mechanisms underlying its dysregulation in hyperglycemia and diabetes. We conclude by examining future directions and gaps in knowledge regarding CaV1.2 regulation in health and during diabetes.
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12
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Largeau B, Bordy R, Pasqualin C, Bredeloux P, Cracowski JL, Lengellé C, Gras-Champel V, Auffret M, Maupoil V, Jonville-Béra AP. Gabapentinoid-induced peripheral edema and acute heart failure: A translational study combining pharmacovigilance data and in vitro animal experiments. Biomed Pharmacother 2022; 149:112807. [PMID: 35303569 DOI: 10.1016/j.biopha.2022.112807] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Revised: 02/20/2022] [Accepted: 03/07/2022] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Gabapentinoids are ligands of the α2-δ subunit of voltage-gated calcium channels (Cav) that have been associated with a risk of peripheral edema and acute heart failure in connection with a potentially dual mechanism, vascular and cardiac. OBJECTIVES & METHODS All cases of peripheral edema or heart failure involving gabapentin or pregabalin reported to the French Pharmacovigilance Centers between January 1, 1994 and April 30, 2020 were included to describe their onset patterns (e.g., time to onset). Based on these data, we investigated the impact of gabapentinoids on the myogenic tone of rat third-order mesenteric arteries and on the electrophysiological properties of rat ventricular cardiomyocytes. RESULTS A total of 58 reports were included (gabapentin n = 5, pregabalin n = 53). The female-to-male ratio was 4:1 and the median age was 77 years (IQR 57-85, range 32-95). The median time to onset were 23 days (IQR 10-54) and 17 days (IQR 3-30) for non-cardiogenic edema and acute heart failure, respectively. Cardiogenic and non-cardiogenic peripheral edema occurred frequently after a dose escalation (27/45, 60%), and the course was rapidly favorable after discontinuation of gabapentinoid (median 7 days, IQR 5-13). On rat mesenteric arteries, gabapentinoids significantly decreased the myogenic tone to the same extent as verapamil and nifedipine. Acute application of gabapentinoids had no significant effect on Cav1.2 currents of ventricular cardiomyocytes. CONCLUSION Gabapentinoids can cause concentration-dependent peripheral edema of early onset. The primary mechanism of non-cardiogenic peripheral edema is vasodilatory edema secondary to altered myogenic tone, independent of Cav1.2 blockade under the experimental conditions tested.
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Affiliation(s)
- Bérenger Largeau
- CHRU de Tours, Service de Pharmacosurveillance, Centre Régional de Pharmacovigilance Centre-Val de Loire, Tours 37044, France.
| | - Romain Bordy
- Université de Tours, Transplantation, Immunologie et Inflammation (T2I) - EA4245, Tours 37044, France.
| | - Côme Pasqualin
- Université de Tours, Transplantation, Immunologie et Inflammation (T2I) - EA4245, Tours 37044, France.
| | - Pierre Bredeloux
- Université de Tours, Transplantation, Immunologie et Inflammation (T2I) - EA4245, Tours 37044, France.
| | - Jean-Luc Cracowski
- CHU Grenoble Alpes, Centre Régional de Pharmacovigilance et d'Information sur les Médicaments, Grenoble 38000, France; University of Grenoble HP2, INSERM, Grenoble, 38000, France.
| | - Céline Lengellé
- CHRU de Tours, Service de Pharmacosurveillance, Centre Régional de Pharmacovigilance Centre-Val de Loire, Tours 37044, France.
| | - Valérie Gras-Champel
- CHU d'Amiens, Service de Pharmacologie Clinique, Centre Régional de Pharmacovigilance d'Amiens, Amiens 80054, France.
| | - Marine Auffret
- Hospices Civils de Lyon, Service Hospitalo-Universitaire de Pharmacotoxicologie, Centre Régional de Pharmacovigilance, Lyon, France.
| | - Véronique Maupoil
- Université de Tours, Transplantation, Immunologie et Inflammation (T2I) - EA4245, Tours 37044, France.
| | - Annie-Pierre Jonville-Béra
- CHRU de Tours, Service de Pharmacosurveillance, Centre Régional de Pharmacovigilance Centre-Val de Loire, Tours 37044, France; Université de Tours, Université de Nantes, INSERM, methodS in Patients-centered outcomes and HEalth ResEarch (SPHERE) - UMR 1246, Tours 37044, France.
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13
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Dixon RE, Navedo MF, Binder MD, Santana LF. Mechanisms and Physiological Implications of Cooperative Gating of Ion Channels Clusters. Physiol Rev 2021; 102:1159-1210. [PMID: 34927454 DOI: 10.1152/physrev.00022.2021] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Ion channels play a central role in the regulation of nearly every cellular process. Dating back to the classic 1952 Hodgkin-Huxley model of the generation of the action potential, ion channels have always been thought of as independent agents. A myriad of recent experimental findings exploiting advances in electrophysiology, structural biology, and imaging techniques, however, have posed a serious challenge to this long-held axiom as several classes of ion channels appear to open and close in a coordinated, cooperative manner. Ion channel cooperativity ranges from variable-sized oligomeric cooperative gating in voltage-gated, dihydropyridine-sensitive Cav1.2 and Cav1.3 channels to obligatory dimeric assembly and gating of voltage-gated Nav1.5 channels. Potassium channels, transient receptor potential channels, hyperpolarization cyclic nucleotide-activated channels, ryanodine receptors (RyRs), and inositol trisphosphate receptors (IP3Rs) have also been shown to gate cooperatively. The implications of cooperative gating of these ion channels range from fine tuning excitation-contraction coupling in muscle cells to regulating cardiac function and vascular tone, to modulation of action potential and conduction velocity in neurons and cardiac cells, and to control of pace-making activity in the heart. In this review, we discuss the mechanisms leading to cooperative gating of ion channels, their physiological consequences and how alterations in cooperative gating of ion channels may induce a range of clinically significant pathologies.
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Affiliation(s)
- Rose Ellen Dixon
- Department of Physiology and Membrane Biology, University of California, Davis, CA, United States
| | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, CA, United States
| | - Marc D Binder
- Department of Physiology and Biophysics, University of Washington, Seattle, WA, United States
| | - L Fernando Santana
- Department of Physiology and Membrane Biology, University of California, Davis, CA, United States
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14
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Negri S, Faris P, Moccia F. Endolysosomal Ca 2+ signaling in cardiovascular health and disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 363:203-269. [PMID: 34392930 DOI: 10.1016/bs.ircmb.2021.03.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
An increase in intracellular Ca2+ concentration ([Ca2+]i) regulates a plethora of functions in the cardiovascular (CV) system, including contraction in cardiomyocytes and vascular smooth muscle cells (VSMCs), and angiogenesis in vascular endothelial cells and endothelial colony forming cells. The sarco/endoplasmic reticulum (SR/ER) represents the largest endogenous Ca2+ store, which releases Ca2+ through ryanodine receptors (RyRs) and/or inositol-1,4,5-trisphosphate receptors (InsP3Rs) upon extracellular stimulation. The acidic vesicles of the endolysosomal (EL) compartment represent an additional endogenous Ca2+ store, which is targeted by several second messengers, including nicotinic acid adenine dinucleotide phosphate (NAADP) and phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2], and may release intraluminal Ca2+ through multiple Ca2+ permeable channels, including two-pore channels 1 and 2 (TPC1-2) and Transient Receptor Potential Mucolipin 1 (TRPML1). Herein, we discuss the emerging, pathophysiological role of EL Ca2+ signaling in the CV system. We describe the role of cardiac TPCs in β-adrenoceptor stimulation, arrhythmia, hypertrophy, and ischemia-reperfusion injury. We then illustrate the role of EL Ca2+ signaling in VSMCs, where TPCs promote vasoconstriction and contribute to pulmonary artery hypertension and atherosclerosis, whereas TRPML1 sustains vasodilation and is also involved in atherosclerosis. Subsequently, we describe the mechanisms whereby endothelial TPCs promote vasodilation, contribute to neurovascular coupling in the brain and stimulate angiogenesis and vasculogenesis. Finally, we discuss about the possibility to target TPCs, which are likely to mediate CV cell infection by the Severe Acute Respiratory Disease-Coronavirus-2, with Food and Drug Administration-approved drugs to alleviate the detrimental effects of Coronavirus Disease-19 on the CV system.
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Affiliation(s)
- Sharon Negri
- Laboratory of Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Pawan Faris
- Laboratory of Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy
| | - Francesco Moccia
- Laboratory of Physiology, Department of Biology and Biotechnology "Lazzaro Spallanzani", University of Pavia, Pavia, Italy.
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15
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Baker SA, Leigh WA, Del Valle G, De Yturriaga IF, Ward SM, Cobine CA, Drumm BT, Sanders KM. Ca 2+ signaling driving pacemaker activity in submucosal interstitial cells of Cajal in the murine colon. eLife 2021; 10:64099. [PMID: 33399536 PMCID: PMC7806270 DOI: 10.7554/elife.64099] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/04/2021] [Indexed: 02/06/2023] Open
Abstract
Interstitial cells of Cajal (ICC) generate pacemaker activity responsible for phasic contractions in colonic segmentation and peristalsis. ICC along the submucosal border (ICC-SM) contribute to mixing and more complex patterns of colonic motility. We show the complex patterns of Ca2+ signaling in ICC-SM and the relationship between ICC-SM Ca2+ transients and activation of smooth muscle cells (SMCs) using optogenetic tools. ICC-SM displayed rhythmic firing of Ca2+transients ~ 15 cpm and paced adjacent SMCs. The majority of spontaneous activity occurred in regular Ca2+ transients clusters (CTCs) that propagated through the network. CTCs were organized and dependent upon Ca2+ entry through voltage-dependent Ca2+ conductances, L- and T-type Ca2+ channels. Removal of Ca2+ from the external solution abolished CTCs. Ca2+ release mechanisms reduced the duration and amplitude of Ca2+ transients but did not block CTCs. These data reveal how colonic pacemaker ICC-SM exhibit complex Ca2+-firing patterns and drive smooth muscle activity and overall colonic contractions.
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Affiliation(s)
- Salah A Baker
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Wesley A Leigh
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Guillermo Del Valle
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Inigo F De Yturriaga
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Sean M Ward
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Caroline A Cobine
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Bernard T Drumm
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
| | - Kenton M Sanders
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, United States
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16
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Nieves-Cintrón M, Flores-Tamez VA, Le T, Baudel MMA, Navedo MF. Cellular and molecular effects of hyperglycemia on ion channels in vascular smooth muscle. Cell Mol Life Sci 2021; 78:31-61. [PMID: 32594191 PMCID: PMC7765743 DOI: 10.1007/s00018-020-03582-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 06/10/2020] [Accepted: 06/22/2020] [Indexed: 12/13/2022]
Abstract
Diabetes affects millions of people worldwide. This devastating disease dramatically increases the risk of developing cardiovascular disorders. A hallmark metabolic abnormality in diabetes is hyperglycemia, which contributes to the pathogenesis of cardiovascular complications. These cardiovascular complications are, at least in part, related to hyperglycemia-induced molecular and cellular changes in the cells making up blood vessels. Whereas the mechanisms mediating endothelial dysfunction during hyperglycemia have been extensively examined, much less is known about how hyperglycemia impacts vascular smooth muscle function. Vascular smooth muscle function is exquisitely regulated by many ion channels, including several members of the potassium (K+) channel superfamily and voltage-gated L-type Ca2+ channels. Modulation of vascular smooth muscle ion channels function by hyperglycemia is emerging as a key contributor to vascular dysfunction in diabetes. In this review, we summarize the current understanding of how diabetic hyperglycemia modulates the activity of these ion channels in vascular smooth muscle. We examine underlying mechanisms, general properties, and physiological relevance in the context of myogenic tone and vascular reactivity.
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Affiliation(s)
- Madeline Nieves-Cintrón
- Department of Pharmacology, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - Víctor A Flores-Tamez
- Department of Pharmacology, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - Thanhmai Le
- Department of Pharmacology, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA
| | | | - Manuel F Navedo
- Department of Pharmacology, University of California Davis, One Shields Avenue, Davis, CA, 95616, USA.
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17
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Prada MP, Syed AU, Reddy GR, Martín-Aragón Baudel M, Flores-Tamez VA, Sasse KC, Ward SM, Sirish P, Chiamvimonvat N, Bartels P, Dickson EJ, Hell JW, Scott JD, Santana LF, Xiang YK, Navedo MF, Nieves-Cintrón M. AKAP5 complex facilitates purinergic modulation of vascular L-type Ca 2+ channel Ca V1.2. Nat Commun 2020; 11:5303. [PMID: 33082339 PMCID: PMC7575592 DOI: 10.1038/s41467-020-18947-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 09/22/2020] [Indexed: 02/08/2023] Open
Abstract
The L-type Ca2+ channel CaV1.2 is essential for arterial myocyte excitability, gene expression and contraction. Elevations in extracellular glucose (hyperglycemia) potentiate vascular L-type Ca2+ channel via PKA, but the underlying mechanisms are unclear. Here, we find that cAMP synthesis in response to elevated glucose and the selective P2Y11 agonist NF546 is blocked by disruption of A-kinase anchoring protein 5 (AKAP5) function in arterial myocytes. Glucose and NF546-induced potentiation of L-type Ca2+ channels, vasoconstriction and decreased blood flow are prevented in AKAP5 null arterial myocytes/arteries. These responses are nucleated via the AKAP5-dependent clustering of P2Y11/ P2Y11-like receptors, AC5, PKA and CaV1.2 into nanocomplexes at the plasma membrane of human and mouse arterial myocytes. Hence, data reveal an AKAP5 signaling module that regulates L-type Ca2+ channel activity and vascular reactivity upon elevated glucose. This AKAP5-anchored nanocomplex may contribute to vascular complications during diabetic hyperglycemia.
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Affiliation(s)
- Maria Paz Prada
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
| | - Arsalan U Syed
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
| | - Gopireddy R Reddy
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
| | | | | | | | - Sean M Ward
- Department of Physiology and Cell Biology, University of Nevada Reno, Reno, NV, 89557, USA
| | - Padmini Sirish
- Department of Internal Medicine, University of California Davis, Davis, CA, 95616, USA
| | - Nipavan Chiamvimonvat
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
- Department of Internal Medicine, University of California Davis, Davis, CA, 95616, USA
- VA Northern California Healthcare System, Mather, CA, 95655, USA
| | - Peter Bartels
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
| | - Eamonn J Dickson
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, 95616, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
| | - John D Scott
- Department of Pharmacology, University of Washington Seattle, Seattle, WA, 98195, USA
| | - Luis F Santana
- Department of Physiology and Membrane Biology, University of California Davis, Davis, CA, 95616, USA
| | - Yang K Xiang
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA
- VA Northern California Healthcare System, Mather, CA, 95655, USA
| | - Manuel F Navedo
- Department of Pharmacology, University of California Davis, Davis, CA, 95616, USA.
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18
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AKAP5 anchors PKA to enhance regulation of the HERG channel. Int J Biochem Cell Biol 2020; 122:105741. [PMID: 32173522 DOI: 10.1016/j.biocel.2020.105741] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 02/24/2020] [Accepted: 03/11/2020] [Indexed: 11/21/2022]
Abstract
The activation of the β-adrenergic receptor (β-AR) regulates the human ether a-go-go-related gene (HERG) channel via protein kinase A (PKA), which in turn induces lethal arrhythmia in patients with long QT syndromes (LQTS). However, the role of A-kinase anchoring proteins (AKAPs) in PKA's regulation of the HERG channel and its molecular mechanism are not clear. Here, HEK293 cells were transfected with the HERG gene alone or co-transfected with HERG and AKAP5 using Lipofectamine 2000. Western blotting was performed to determine HERG protein expression, and immunofluorescence and immunoprecipitation were used to assess the binding and cellular colocalization of HERG, AKAP5, and PKA. The HEK293-HERG and HEK293-HERG + AKAP5 cells were treated with forskolin at different concentrations and different time. HERG protein expression significantly increased under all treatment conditions (P < 0.001). The level of HERG protein expression in HEK293-HERG + AKAP5 cells was higher than that observed in HEK293-HERG cells (P < 0.001). Immunofluorescence and immunoprecipitation indicated that HERG bound to PKA and AKAP5 and was colocalized at the cell membrane. The HERG channel protein, AKAP5, and PKA interacted with each other and appeared to form intracellular complexes. These results provide evidence for a novel mechanism which AKAP5 anchors PKA to up-regulate the HERG channel protein.
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19
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Manoury B, Idres S, Leblais V, Fischmeister R. Ion channels as effectors of cyclic nucleotide pathways: Functional relevance for arterial tone regulation. Pharmacol Ther 2020; 209:107499. [PMID: 32068004 DOI: 10.1016/j.pharmthera.2020.107499] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 02/05/2020] [Indexed: 02/07/2023]
Abstract
Numerous mediators and drugs regulate blood flow or arterial pressure by acting on vascular tone, involving cyclic nucleotide intracellular pathways. These signals lead to regulation of several cellular effectors, including ion channels that tune cell membrane potential, Ca2+ influx and vascular tone. The characterization of these vasocontrictive or vasodilating mechanisms has grown in complexity due to i) the variety of ion channels that are expressed in both vascular endothelial and smooth muscle cells, ii) the heterogeneity of responses among the various vascular beds, and iii) the number of molecular mechanisms involved in cyclic nucleotide signalling in health and disease. This review synthesizes key data from literature that highlight ion channels as physiologically relevant effectors of cyclic nucleotide pathways in the vasculature, including the characterization of the molecular mechanisms involved. In smooth muscle cells, cation influx or chloride efflux through ion channels are associated with vasoconstriction, whereas K+ efflux repolarizes the cell membrane potential and mediates vasodilatation. Both categories of ion currents are under the influence of cAMP and cGMP pathways. Evidence that some ion channels are influenced by CN signalling in endothelial cells will also be presented. Emphasis will also be put on recent data touching a variety of determinants such as phosphodiesterases, EPAC and kinase anchoring, that complicate or even challenge former paradigms.
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Affiliation(s)
- Boris Manoury
- Inserm, Umr-S 1180, Université Paris-Saclay, Châtenay-Malabry, France.
| | - Sarah Idres
- Inserm, Umr-S 1180, Université Paris-Saclay, Châtenay-Malabry, France
| | - Véronique Leblais
- Inserm, Umr-S 1180, Université Paris-Saclay, Châtenay-Malabry, France
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20
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Kv2.1 channels play opposing roles in regulating membrane potential, Ca 2+ channel function, and myogenic tone in arterial smooth muscle. Proc Natl Acad Sci U S A 2020; 117:3858-3866. [PMID: 32015129 PMCID: PMC7035623 DOI: 10.1073/pnas.1917879117] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The accepted role of the protein Kv2.1 in arterial smooth muscle cells is to form K+ channels in the sarcolemma. Opening of Kv2.1 channels causes membrane hyperpolarization, which decreases the activity of L-type CaV1.2 channels, lowering intracellular Ca2+ ([Ca2+]i) and causing smooth muscle relaxation. A limitation of this model is that it is based exclusively on data from male arterial myocytes. Here, we used a combination of electrophysiology as well as imaging approaches to investigate the role of Kv2.1 channels in male and female arterial myocytes. We confirmed that Kv2.1 plays a canonical conductive role but found it also has a structural role in arterial myocytes to enhance clustering of CaV1.2 channels. Less than 1% of Kv2.1 channels are conductive and induce membrane hyperpolarization. Paradoxically, by enhancing the structural clustering and probability of CaV1.2-CaV1.2 interactions within these clusters, Kv2.1 increases Ca2+ influx. These functional impacts of Kv2.1 depend on its level of expression, which varies with sex. In female myocytes, where expression of Kv2.1 protein is higher than in male myocytes, Kv2.1 has conductive and structural roles. Female myocytes have larger CaV1.2 clusters, larger [Ca2+]i, and larger myogenic tone than male myocytes. In contrast, in male myocytes, Kv2.1 channels regulate membrane potential but not CaV1.2 channel clustering. We propose a model in which Kv2.1 function varies with sex: in males, Kv2.1 channels control membrane potential but, in female myocytes, Kv2.1 plays dual electrical and CaV1.2 clustering roles. This contributes to sex-specific regulation of excitability, [Ca2+]i, and myogenic tone in arterial myocytes.
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21
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Abstract
Calcium (Ca2+) signalling is of paramount importance to immunity. Regulated increases in cytosolic and organellar Ca2+ concentrations in lymphocytes control complex and crucial effector functions such as metabolism, proliferation, differentiation, antibody and cytokine secretion and cytotoxicity. Altered Ca2+ regulation in lymphocytes leads to various autoimmune, inflammatory and immunodeficiency syndromes. Several types of plasma membrane and organellar Ca2+-permeable channels are functional in T cells. They contribute highly localized spatial and temporal Ca2+ microdomains that are required for achieving functional specificity. While the mechanistic details of these Ca2+ microdomains are only beginning to emerge, it is evident that through crosstalk, synergy and feedback mechanisms, they fine-tune T cell signalling to match complex immune responses. In this article, we review the expression and function of various Ca2+-permeable channels in the plasma membrane, endoplasmic reticulum, mitochondria and endolysosomes of T cells and their role in shaping immunity and the pathogenesis of immune-mediated diseases.
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Affiliation(s)
- Mohamed Trebak
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, PA, USA.
| | - Jean-Pierre Kinet
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
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22
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Han D, Xu L, Liu P, Liu Y, Sun C, Yin Y. Allicin disrupts cardiac Cav1.2 channels via trafficking. PHARMACEUTICAL BIOLOGY 2019; 57:245-249. [PMID: 30929547 PMCID: PMC6450490 DOI: 10.1080/13880209.2019.1577469] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 10/06/2018] [Accepted: 01/25/2019] [Indexed: 06/09/2023]
Abstract
CONTEXT Allicin is a potential antiarrhythmic agent. The antiarrhythmic properties of allicin rely on its blockade of various cardiac ion channels. The l-type calcium (Cav1.2) channel provides a pivotal substrate for cardiac electrophysiologic activities. The mechanism of allicin on Cav1.2 remains unclear. OBJECTIVE This study evaluated the potential of allicin on the synthesis and trafficking of Cav1.2 channels. MATERIALS AND METHODS Primary cardiomyocytes (CMs) from neonatal Sprague-Dawley (SD) rats were exposed to allicin (0, 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 μg/mL) for 24 and 48 h. The CellTiter-Glo assay was performed to measure CM viability. Western blot with grayscale analysis and confocal laser scanning microscopy were used to evaluate the effects of allicin on the synthesis and trafficking of Cav1.2 channel proteins in primary CMs. RESULTS There was no significant difference in apoptotic toxicity from the actual cell viability (p > 0.05) in any group (0, 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 μg/mL allicin), except that viability in the 0.001 and 0.01 μg/mL groups at 24 h were significantly greater (137.37 and 135.96%) (p < 0.05). Western blot with grayscale analysis revealed no substantial inhibition by allicin of the synthesis of Cav1.2 proteins. Confocal laser scanning microscopy revealed trafficking dysfunction of Cav1.2 channels caused by allicin in primary CMs. CONCLUSION This study is the first to demonstrate that allicin inhibits cardiac Cav1.2 channels by disrupting trafficking, possibly mediating its antiarrhythmic benefits. Therefore, allicin might serve as a new antiarrhythmic agent in the future.
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Affiliation(s)
- Dan Han
- Arrhythmia Unit, Department of Cardiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Lingping Xu
- Arrhythmia Unit, Department of Cardiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
- Xianyang Central Hospital, Xianyang, China
| | - Peng Liu
- Arrhythmia Unit, Department of Cardiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Yingying Liu
- Arrhythmia Unit, Department of Cardiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Chaofeng Sun
- Arrhythmia Unit, Department of Cardiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
| | - Yanrong Yin
- Arrhythmia Unit, Department of Cardiology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, China
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23
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Zhu YR, Jiang XX, Zheng Y, Xiong J, Wei D, Zhang DM. Cardiac function modulation depends on the A-kinase anchoring protein complex. J Cell Mol Med 2019; 23:7170-7179. [PMID: 31512389 PMCID: PMC6815827 DOI: 10.1111/jcmm.14659] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 06/27/2019] [Accepted: 08/06/2019] [Indexed: 12/26/2022] Open
Abstract
The A‐kinase anchoring proteins (AKAPs) are a group of structurally diverse proteins identified in various species and tissues. These proteins are able to anchor protein kinase and other signalling proteins to regulate cardiac function. Acting as a scaffold protein, AKAPs ensure specificity in signal transduction by enzymes close to their appropriate effectors and substrates. Over the decades, more than 70 different AKAPs have been discovered. Accumulative evidence indicates that AKAPs play crucial roles in the functional regulation of cardiac diseases, including cardiac hypertrophy, myofibre contractility dysfunction and arrhythmias. By anchoring different partner proteins (PKA, PKC, PKD and LTCCs), AKAPs take part in different regulatory pathways to function as regulators in the heart, and a damaged structure can influence the activities of these complexes. In this review, we highlight recent advances in AKAP‐associated protein complexes, focusing on local signalling events that are perturbed in cardiac diseases and their roles in interacting with ion channels and their regulatory molecules. These new findings suggest that AKAPs might have potential therapeutic value in patients with cardiac diseases, particularly malignant rhythm.
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Affiliation(s)
- Yan-Rong Zhu
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Xiao-Xin Jiang
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Yaguo Zheng
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Jing Xiong
- Department of Pharmacology, Nanjing Medical University, Nanjing, China
| | - Dongping Wei
- Department of Oncology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
| | - Dai-Min Zhang
- Department of Cardiology, Nanjing First Hospital, Nanjing Medical University, Nanjing, China
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24
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Shah SI, Demuro A, Mak DOD, Parker I, Pearson JE, Ullah G. TraceSpecks: A Software for Automated Idealization of Noisy Patch-Clamp and Imaging Data. Biophys J 2019; 115:9-21. [PMID: 29972815 DOI: 10.1016/j.bpj.2018.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 05/15/2018] [Accepted: 06/04/2018] [Indexed: 10/28/2022] Open
Abstract
Experimental records of single molecules or ion channels from fluorescence microscopy and patch-clamp electrophysiology often include high-frequency noise and baseline fluctuations that are not generated by the system under investigation and have to be removed. Moreover, multiple channels or conductance levels can be present at a time in the data that need to be quantified to accurately understand the behavior of the system. Manual procedures for removing these fluctuations and extracting conducting states or multiple channels are laborious, prone to subjective bias, and likely to hinder the processing of often very large data sets. We introduce a maximal likelihood formalism for separating signal from a noisy and drifting background such as fluorescence traces from imaging of elementary Ca2+ release events called puffs arising from clusters of channels, and patch-clamp recordings of ion channels. Parameters such as the number of open channels or conducting states, noise level, and background signal can all be optimized using the expectation-maximization algorithm. We implement our algorithm following the Baum-Welch approach to expectation-maximization in the portable Java language with a user-friendly graphical interface and test the algorithm on both synthetic and experimental data from the patch-clamp electrophysiology of Ca2+ channels and fluorescence microscopy of a cluster of Ca2+ channels and Ca2+ channels with multiple conductance levels. The resulting software is accurate, fast, and provides detailed information usually not available through manual analysis. Options for visual inspection of the raw and processed data with key parameters are provided, in addition to a range of statistics such as the mean open probabilities, mean open times, mean close times, dwell-time distributions for different number of channels open or conductance levels, amplitude distribution of all opening events, and number of transitions between different number of open channels or conducting levels in asci format with a single click.
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Affiliation(s)
| | - Angelo Demuro
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, California
| | - Don-On Daniel Mak
- Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Ian Parker
- Department of Neurobiology and Behavior, University of California, Irvine, Irvine, California; Department of Physiology and Biophysics, University of California, Irvine, Irvine, California
| | - John E Pearson
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, New Mexico
| | - Ghanim Ullah
- Department of Physics, University of South Florida, Tampa, Florida.
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25
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Shah SI, Smith M, Swaminathan D, Parker I, Ullah G, Demuro A. CellSpecks: A Software for Automated Detection and Analysis of Calcium Channels in Live Cells. Biophys J 2018; 115:2141-2151. [PMID: 30447989 DOI: 10.1016/j.bpj.2018.10.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 09/27/2018] [Accepted: 10/22/2018] [Indexed: 02/01/2023] Open
Abstract
To couple the fidelity of patch-clamp recording with a more high-throughput screening capability, we pioneered a, to our knowledge, novel approach to single-channel recording that we named "optical patch clamp." By using highly sensitive fluorescent Ca2+ indicator dyes in conjunction with total internal fluorescence microscopy techniques, we monitor Ca2+ flux through individual Ca2+-permeable channels. This approach provides information about channel gating analogous to patch-clamp recording at a time resolution of ∼2 ms with the additional advantage of being massively parallel, providing simultaneous and independent recording from thousands of channels in the native environment. However, manual analysis of the data generated by this technique presents severe challenges because a video recording can include many thousands of frames. To overcome this bottleneck, we developed an image processing and analysis framework called CellSpecks capable of detecting and fully analyzing the kinetics of ion channels within a video sequence. By using randomly generated synthetic data, we tested the ability of CellSpecks to rapidly and efficiently detect and analyze the activity of thousands of ion channels, including openings for a few milliseconds. Here, we report the use of CellSpecks for the analysis of experimental data acquired by imaging muscle nicotinic acetylcholine receptors and the Alzheimer's disease-associated amyloid β pores with multiconductance levels in the plasma membrane of Xenopus laevis oocytes. We show that CellSpecks can accurately and efficiently generate location maps and create raw and processed fluorescence time traces; histograms of mean open times, mean close times, open probabilities, durations, and maximal amplitudes; and a "channel chip" showing the activity of all channels as a function of time. Although we specifically illustrate the application of CellSpecks for analyzing data from Ca2+ channels, it can be easily customized to analyze other spatially and temporally localized signals.
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Affiliation(s)
| | | | - Divya Swaminathan
- Department of Neurobiology and Behavior,University of California Irvine, Irvine, California
| | - Ian Parker
- Department of Neurobiology and Behavior,University of California Irvine, Irvine, California; Department of Physiology and Biophysics, University of California Irvine, Irvine, California
| | - Ghanim Ullah
- Department of Physics, University of South Florida, Tampa, Florida.
| | - Angelo Demuro
- Department of Neurobiology and Behavior,University of California Irvine, Irvine, California.
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Ghosh D, Nieves-Cintrón M, Tajada S, Brust-Mascher I, Horne MC, Hell JW, Dixon RE, Santana LF, Navedo MF. Dynamic L-type Ca V1.2 channel trafficking facilitates Ca V1.2 clustering and cooperative gating. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1341-1355. [PMID: 29959960 PMCID: PMC6407617 DOI: 10.1016/j.bbamcr.2018.06.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 06/22/2018] [Accepted: 06/26/2018] [Indexed: 11/21/2022]
Abstract
L-type CaV1.2 channels are key regulators of gene expression, cell excitability and muscle contraction. CaV1.2 channels organize in clusters throughout the plasma membrane. This channel organization has been suggested to contribute to the concerted activation of adjacent CaV1.2 channels (e.g. cooperative gating). Here, we tested the hypothesis that dynamic intracellular and perimembrane trafficking of CaV1.2 channels is critical for formation and dissolution of functional channel clusters mediating cooperative gating. We found that CaV1.2 moves in vesicular structures of circular and tubular shape with diverse intracellular and submembrane trafficking patterns. Both microtubules and actin filaments are required for dynamic movement of CaV1.2 vesicles. These vesicles undergo constitutive homotypic fusion and fission events that sustain CaV1.2 clustering, channel activity and cooperative gating. Our study suggests that CaV1.2 clusters and activity can be modulated by diverse and unique intracellular and perimembrane vesicular dynamics to fine-tune Ca2+ signals.
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Affiliation(s)
- Debapriya Ghosh
- Department of Pharmacology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Madeline Nieves-Cintrón
- Department of Pharmacology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Sendoa Tajada
- Department of Physiology & Membrane Biology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Ingrid Brust-Mascher
- Advanced Imaging Facility, School of Veterinary Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Mary C Horne
- Department of Pharmacology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Johannes W Hell
- Department of Pharmacology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Rose E Dixon
- Department of Physiology & Membrane Biology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Luis F Santana
- Department of Physiology & Membrane Biology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA
| | - Manuel F Navedo
- Department of Pharmacology, School of Medicine, One Shields Avenue, University of California, Davis, CA 95616, USA.
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Ercu M, Klussmann E. Roles of A-Kinase Anchoring Proteins and Phosphodiesterases in the Cardiovascular System. J Cardiovasc Dev Dis 2018; 5:jcdd5010014. [PMID: 29461511 PMCID: PMC5872362 DOI: 10.3390/jcdd5010014] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/16/2018] [Accepted: 02/18/2018] [Indexed: 12/13/2022] Open
Abstract
A-kinase anchoring proteins (AKAPs) and cyclic nucleotide phosphodiesterases (PDEs) are essential enzymes in the cyclic adenosine 3′-5′ monophosphate (cAMP) signaling cascade. They establish local cAMP pools by controlling the intensity, duration and compartmentalization of cyclic nucleotide-dependent signaling. Various members of the AKAP and PDE families are expressed in the cardiovascular system and direct important processes maintaining homeostatic functioning of the heart and vasculature, e.g., the endothelial barrier function and excitation-contraction coupling. Dysregulation of AKAP and PDE function is associated with pathophysiological conditions in the cardiovascular system including heart failure, hypertension and atherosclerosis. A number of diseases, including autosomal dominant hypertension with brachydactyly (HTNB) and type I long-QT syndrome (LQT1), result from mutations in genes encoding for distinct members of the two classes of enzymes. This review provides an overview over the AKAPs and PDEs relevant for cAMP compartmentalization in the heart and vasculature and discusses their pathophysiological role as well as highlights the potential benefits of targeting these proteins and their protein-protein interactions for the treatment of cardiovascular diseases.
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Affiliation(s)
- Maria Ercu
- Max Delbrück Center for Molecular Medicine Berlin (MDC), Berlin 13125, Germany.
| | - Enno Klussmann
- Max Delbrück Center for Molecular Medicine Berlin (MDC), Berlin 13125, Germany.
- DZHK (German Centre for Cardiovascular Research), partner site Berlin 13347, Germany.
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28
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Sato D, Dixon RE, Santana LF, Navedo MF. A model for cooperative gating of L-type Ca2+ channels and its effects on cardiac alternans dynamics. PLoS Comput Biol 2018; 14:e1005906. [PMID: 29338006 PMCID: PMC5786340 DOI: 10.1371/journal.pcbi.1005906] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 01/26/2018] [Accepted: 11/29/2017] [Indexed: 11/18/2022] Open
Abstract
In ventricular myocytes, membrane depolarization during the action potential (AP) causes synchronous activation of multiple L-type CaV1.2 channels (LTCCs), which trigger the release of calcium (Ca2+) from the sarcoplasmic reticulum (SR). This results in an increase in intracellular Ca2+ (Cai) that initiates contraction. During pulsus alternans, cardiac contraction is unstable, going from weak to strong in successive beats despite a constant heart rate. These cardiac alternans can be caused by the instability of membrane potential (Vm) due to steep AP duration (APD) restitution (Vm-driven alternans), instability of Cai cycling (Ca2+-driven alternans), or both, and may be modulated by functional coupling between clustered CaV1.2 (e.g. cooperative gating). Here, mathematical analysis and computational models were used to determine how changes in the strength of cooperative gating between LTCCs may impact membrane voltage and intracellular Ca2+ dynamics in the heart. We found that increasing the degree of coupling between LTCCs increases the amplitude of Ca2+ currents (ICaL) and prolongs AP duration (APD). Increased AP duration is known to promote cardiac alternans, a potentially arrhythmogenic substrate. In addition, our analysis shows that increasing the strength of cooperative activation of LTCCs makes the coupling of Ca2+ on the membrane voltage (Cai→Vm coupling) more positive and destabilizes the Vm-Cai dynamics for Vm-driven alternans and Cai-driven alternans, but not for quasiperiodic oscillation. These results suggest that cooperative gating of LTCCs may have a major impact on cardiac excitation-contraction coupling, not only by prolonging APD, but also by altering Cai→Vm coupling and potentially promoting cardiac arrhythmias.
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Affiliation(s)
- Daisuke Sato
- Department of Pharmacology, University of California, Davis, Davis, CA, USA
- * E-mail:
| | - Rose E. Dixon
- Department of Physiology & Membrane Biology, University of California, Davis, Davis, CA, USA
| | - Luis F. Santana
- Department of Physiology & Membrane Biology, University of California, Davis, Davis, CA, USA
| | - Manuel F. Navedo
- Department of Pharmacology, University of California, Davis, Davis, CA, USA
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29
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Sato Y, Nagatoshi K, Hamano A, Imamura Y, Huss D, Uchida S, Lansford R. Basal filopodia and vascular mechanical stress organize fibronectin into pillars bridging the mesoderm-endoderm gap. Development 2017; 144:281-291. [PMID: 28096216 DOI: 10.1242/dev.141259] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/29/2016] [Indexed: 12/23/2022]
Abstract
Cells may exchange information with other cells and tissues by exerting forces on the extracellular matrix (ECM). Fibronectin (FN) is an important ECM component that forms fibrils through cell contacts and creates directionally biased geometry. Here, we demonstrate that FN is deposited as pillars between widely separated germ layers, namely the somitic mesoderm and the endoderm, in quail embryos. Alongside the FN pillars, long filopodia protrude from the basal surfaces of somite epithelial cells. Loss-of-function of Ena/VASP, α5β1-integrins or talin in the somitic cells abolished the FN pillars, indicating that FN pillar formation is dependent on the basal filopodia through these molecules. The basal filopodia and FN pillars are also necessary for proper somite morphogenesis. We identified a new mechanism contributing to FN pillar formation by focusing on cyclic expansion of adjacent dorsal aorta. Maintenance of the directional alignment of the FN pillars depends on pulsatile blood flow through the dorsal aortae. These results suggest that the FN pillars are specifically established through filopodia-mediated and pulsating force-related mechanisms.
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Affiliation(s)
- Yuki Sato
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan .,JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Kei Nagatoshi
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Ayumi Hamano
- Department of Advanced Information Technology, Faculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0385, Japan
| | - Yuko Imamura
- Graduate School of Science, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - David Huss
- Department of Radiology and Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA.,Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Seiichi Uchida
- Department of Advanced Information Technology, Faculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0385, Japan
| | - Rusty Lansford
- Department of Radiology and Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA.,Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
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30
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Tykocki NR, Boerman EM, Jackson WF. Smooth Muscle Ion Channels and Regulation of Vascular Tone in Resistance Arteries and Arterioles. Compr Physiol 2017; 7:485-581. [PMID: 28333380 DOI: 10.1002/cphy.c160011] [Citation(s) in RCA: 212] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Vascular tone of resistance arteries and arterioles determines peripheral vascular resistance, contributing to the regulation of blood pressure and blood flow to, and within the body's tissues and organs. Ion channels in the plasma membrane and endoplasmic reticulum of vascular smooth muscle cells (SMCs) in these blood vessels importantly contribute to the regulation of intracellular Ca2+ concentration, the primary determinant of SMC contractile activity and vascular tone. Ion channels provide the main source of activator Ca2+ that determines vascular tone, and strongly contribute to setting and regulating membrane potential, which, in turn, regulates the open-state-probability of voltage gated Ca2+ channels (VGCCs), the primary source of Ca2+ in resistance artery and arteriolar SMCs. Ion channel function is also modulated by vasoconstrictors and vasodilators, contributing to all aspects of the regulation of vascular tone. This review will focus on the physiology of VGCCs, voltage-gated K+ (KV) channels, large-conductance Ca2+-activated K+ (BKCa) channels, strong-inward-rectifier K+ (KIR) channels, ATP-sensitive K+ (KATP) channels, ryanodine receptors (RyRs), inositol 1,4,5-trisphosphate receptors (IP3Rs), and a variety of transient receptor potential (TRP) channels that contribute to pressure-induced myogenic tone in resistance arteries and arterioles, the modulation of the function of these ion channels by vasoconstrictors and vasodilators, their role in the functional regulation of tissue blood flow and their dysfunction in diseases such as hypertension, obesity, and diabetes. © 2017 American Physiological Society. Compr Physiol 7:485-581, 2017.
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Affiliation(s)
- Nathan R Tykocki
- Department of Pharmacology, University of Vermont, Burlington, Vermont, USA
| | - Erika M Boerman
- Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, Missouri, USA
| | - William F Jackson
- Department of Pharmacology and Toxicology, Michigan State University, East Lansing, Michigan, USA
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31
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Nystoriak MA, Nieves-Cintrón M, Patriarchi T, Buonarati OR, Prada MP, Morotti S, Grandi E, Fernandes JDS, Forbush K, Hofmann F, Sasse KC, Scott JD, Ward SM, Hell JW, Navedo MF. Ser1928 phosphorylation by PKA stimulates the L-type Ca2+ channel CaV1.2 and vasoconstriction during acute hyperglycemia and diabetes. Sci Signal 2017; 10:10/463/eaaf9647. [PMID: 28119464 DOI: 10.1126/scisignal.aaf9647] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Hypercontractility of arterial myocytes and enhanced vascular tone during diabetes are, in part, attributed to the effects of increased glucose (hyperglycemia) on L-type CaV1.2 channels. In murine arterial myocytes, kinase-dependent mechanisms mediate the increase in CaV1.2 activity in response to increased extracellular glucose. We identified a subpopulation of the CaV1.2 channel pore-forming subunit (α1C) within nanometer proximity of protein kinase A (PKA) at the sarcolemma of murine and human arterial myocytes. This arrangement depended upon scaffolding of PKA by an A-kinase anchoring protein 150 (AKAP150) in mice. Glucose-mediated increases in CaV1.2 channel activity were associated with PKA activity, leading to α1C phosphorylation at Ser1928 Compared to arteries from low-fat diet (LFD)-fed mice and nondiabetic patients, arteries from high-fat diet (HFD)-fed mice and from diabetic patients had increased Ser1928 phosphorylation and CaV1.2 activity. Arterial myocytes and arteries from mice lacking AKAP150 or expressing mutant AKAP150 unable to bind PKA did not exhibit increased Ser1928 phosphorylation and CaV1.2 current density in response to increased glucose or to HFD. Consistent with a functional role for Ser1928 phosphorylation, arterial myocytes and arteries from knockin mice expressing a CaV1.2 with Ser1928 mutated to alanine (S1928A) lacked glucose-mediated increases in CaV1.2 activity and vasoconstriction. Furthermore, the HFD-induced increases in CaV1.2 current density and myogenic tone were prevented in S1928A knockin mice. These findings reveal an essential role for α1C phosphorylation at Ser1928 in stimulating CaV1.2 channel activity and vasoconstriction by AKAP-targeted PKA upon exposure to increased glucose and in diabetes.
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Affiliation(s)
- Matthew A Nystoriak
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | | | - Tommaso Patriarchi
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | - Olivia R Buonarati
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | - Maria Paz Prada
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | - Stefano Morotti
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | - Eleonora Grandi
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | | | - Katherine Forbush
- Howard Hughes Medical Institute and Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Franz Hofmann
- Department of Pharmacology and Toxicology, Technical University of Munich, Munich D80802, Germany
| | | | - John D Scott
- Howard Hughes Medical Institute and Department of Pharmacology, University of Washington, Seattle, WA 98195, USA
| | - Sean M Ward
- Department of Physiology and Cell Biology, University of Nevada, Reno, NV 89557, USA
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA
| | - Manuel F Navedo
- Department of Pharmacology, University of California, Davis, Davis, CA 95616, USA.
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Endoplasmic Reticulum-Plasma Membrane Contacts Regulate Cellular Excitability. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 997:95-109. [DOI: 10.1007/978-981-10-4567-7_7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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33
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Ghosh D, Syed AU, Prada MP, Nystoriak MA, Santana LF, Nieves-Cintrón M, Navedo MF. Calcium Channels in Vascular Smooth Muscle. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2016; 78:49-87. [PMID: 28212803 DOI: 10.1016/bs.apha.2016.08.002] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Calcium (Ca2+) plays a central role in excitation, contraction, transcription, and proliferation of vascular smooth muscle cells (VSMs). Precise regulation of intracellular Ca2+ concentration ([Ca2+]i) is crucial for proper physiological VSM function. Studies over the last several decades have revealed that VSMs express a variety of Ca2+-permeable channels that orchestrate a dynamic, yet finely tuned regulation of [Ca2+]i. In this review, we discuss the major Ca2+-permeable channels expressed in VSM and their contribution to vascular physiology and pathology.
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Affiliation(s)
- D Ghosh
- University of California, Davis, CA, United States
| | - A U Syed
- University of California, Davis, CA, United States
| | - M P Prada
- University of California, Davis, CA, United States
| | - M A Nystoriak
- Diabetes and Obesity Center, University of Louisville, Louisville, KY, United States
| | - L F Santana
- University of California, Davis, CA, United States
| | | | - M F Navedo
- University of California, Davis, CA, United States.
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34
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Hu R, Li SL, Bai HT, Wang YX, Liu LB, Lv FT, Wang S. Regulation of oxidative stress inside living cells through polythiophene derivatives. CHINESE CHEM LETT 2016. [DOI: 10.1016/j.cclet.2016.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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35
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Tarasova EO, Miteva AS, Gaidukov AE, Balezina OP. The role of adenosine receptors and L-type calcium channels in the regulation of the mediator secretion in mouse motor synapses. BIOCHEMISTRY MOSCOW SUPPLEMENT SERIES A-MEMBRANE AND CELL BIOLOGY 2015. [DOI: 10.1134/s1990747815050141] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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36
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Frolov RV, Weckström M. Harnessing the Flow of Excitation: TRP, Voltage-Gated Na(+), and Voltage-Gated Ca(2+) Channels in Contemporary Medicine. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2015; 103:25-95. [PMID: 26920687 DOI: 10.1016/bs.apcsb.2015.11.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cellular signaling in both excitable and nonexcitable cells involves several classes of ion channels. Some of them are of minor importance, with very specialized roles in physiology, but here we concentrate on three major channel classes: TRP (transient receptor potential channels), voltage-gated sodium channels (Nav), and voltage-gated calcium channels (Cav). Here, we first propose a conceptual framework binding together all three classes of ion channels, a "flow-of-excitation model" that takes into account the inputs mediated by TRP and other similar channels, the outputs invariably provided by Cav channels, and the regenerative transmission of signals in the neural networks, for which Nav channels are responsible. We use this framework to examine the function, structure, and pharmacology of these channel classes both at cellular and also at whole-body physiological level. Building on that basis we go through the pathologies arising from the direct or indirect malfunction of the channels, utilizing ion channel defects, the channelopathies. The pharmacological interventions affecting these channels are numerous. Part of those are well-established treatments, like treatment of hypertension or some forms of epilepsy, but many other are deeply problematic due to poor drug specificity, ion channel diversity, and widespread expression of the channels in tissues other than those actually targeted.
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Affiliation(s)
- Roman V Frolov
- Division of Biophysics, Department of Physics, University of Oulu, Oulun Yliopisto, Finland.
| | - Matti Weckström
- Division of Biophysics, Department of Physics, University of Oulu, Oulun Yliopisto, Finland
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37
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Diviani D, Reggi E, Arambasic M, Caso S, Maric D. Emerging roles of A-kinase anchoring proteins in cardiovascular pathophysiology. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1863:1926-36. [PMID: 26643253 DOI: 10.1016/j.bbamcr.2015.11.024] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/20/2015] [Accepted: 11/23/2015] [Indexed: 01/08/2023]
Abstract
Heart and blood vessels ensure adequate perfusion of peripheral organs with blood and nutrients. Alteration of the homeostatic functions of the cardiovascular system can cause hypertension, atherosclerosis, and coronary artery disease leading to heart injury and failure. A-kinase anchoring proteins (AKAPs) constitute a family of scaffolding proteins that are crucially involved in modulating the function of the cardiovascular system both under physiological and pathological conditions. AKAPs assemble multifunctional signaling complexes that ensure correct targeting of the cAMP-dependent protein kinase (PKA) as well as other signaling enzymes to precise subcellular compartments. This allows local regulation of specific effector proteins that control the function of vascular and cardiac cells. This review will focus on recent advances illustrating the role of AKAPs in cardiovascular pathophysiology. The accent will be mainly placed on the molecular events linked to the control of vascular integrity and blood pressure as well as on the cardiac remodeling process associated with heart failure. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.
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Affiliation(s)
- Dario Diviani
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland.
| | - Erica Reggi
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| | - Miroslav Arambasic
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| | - Stefania Caso
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
| | - Darko Maric
- Département de Pharmacologie et de Toxicologie, Faculté de Biologie et de Médecine, Lausanne 1005, Switzerland
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38
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Mauban JRH, Zacharia J, Fairfax S, Wier WG. PC-PLC/sphingomyelin synthase activity plays a central role in the development of myogenic tone in murine resistance arteries. Am J Physiol Heart Circ Physiol 2015; 308:H1517-24. [PMID: 25888510 DOI: 10.1152/ajpheart.00594.2014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 04/03/2015] [Indexed: 11/22/2022]
Abstract
Myogenic tone is an intrinsic property of the vasculature that contributes to blood pressure control and tissue perfusion. Earlier investigations assigned a key role in myogenic tone to phospholipase C (PLC) and its products, inositol 1,4,5-trisphosphate (IP3) and diacylglycerol (DAG). Here, we used the PLC inhibitor, U-73122, and two other, specific inhibitors of PLC subtypes (PI-PLC and PC-PLC) to delineate the role of PLC in myogenic tone of pressurized murine mesenteric arteries. U-73122 inhibited depolarization-induced contractions (high external K(+) concentration), thus confirming reports of nonspecific actions of U-73122 and its limited utility for studies of myogenic tone. Edelfosine, a specific inhibitor of PI-PLC, did not affect depolarization-induced contractions but modulated myogenic tone. Because PI-PLC produces IP3, we investigated the effect of blocking IP3 receptor-mediated Ca(2+) release on myogenic tone. Incubation of arteries with xestospongin C did not affect tone, consistent with the virtual absence of Ca(2+) waves in arteries with myogenic tone. D-609, an inhibitor of PC-PLC and sphingomyelin synthase, strongly inhibited myogenic tone and had no effect on depolarization-induced contraction. D-609 appeared to act by lowering cytoplasmic Ca(2+) concentration to levels below those that activate contraction. Importantly, incubation of pressurized arteries with a membrane-permeable analog of DAG induced vasoconstriction. The results therefore mandate a reexamination of the signaling pathways activated by the Bayliss mechanism. Our results suggest that PI-PLC and IP3 are not required in maintaining myogenic tone, but DAG, produced by PC-PLC and/or SM synthase, is likely through multiple mechanisms to increase Ca(2+) entry and promote vasoconstriction.
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Affiliation(s)
- Joseph R H Mauban
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
| | - Joseph Zacharia
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
| | - Seth Fairfax
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
| | - Withrow Gil Wier
- Department of Physiology, School of Medicine, University of Maryland Baltimore, Baltimore, Maryland
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Nieves-Cintrón M, Nystoriak MA, Prada MP, Johnson K, Fayer W, Dell'Acqua ML, Scott JD, Navedo MF. Selective down-regulation of KV2.1 function contributes to enhanced arterial tone during diabetes. J Biol Chem 2015; 290:7918-29. [PMID: 25670860 DOI: 10.1074/jbc.m114.622811] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Enhanced arterial tone is a leading cause of vascular complications during diabetes. Voltage-gated K(+) (KV) channels are key regulators of vascular smooth muscle cells (VSMCs) contractility and arterial tone. Whether impaired KV channel function contributes to enhance arterial tone during diabetes is unclear. Here, we demonstrate a reduction in KV-mediated currents (IKv) in VSMCs from a high fat diet (HFD) mouse model of type 2 diabetes. In particular, IKv sensitive to stromatoxin (ScTx), a potent KV2 blocker, were selectively reduced in diabetic VSMCs. This was associated with decreased KV2-mediated regulation of arterial tone and suppression of the KV2.1 subunit mRNA and protein in VSMCs/arteries isolated from HFD mice. We identified protein kinase A anchoring protein 150 (AKAP150), via targeting of the phosphatase calcineurin (CaN), and the transcription factor nuclear factor of activated T-cells c3 (NFATc3) as required determinants of KV2.1 suppression during diabetes. Interestingly, substantial reduction in transcript levels for KV2.1 preceded down-regulation of large conductance Ca(2+)-activated K(+) (BKCa) channel β1 subunits, which are ultimately suppressed in chronic hyperglycemia to a similar extent. Together, our study supports the concept that transcriptional suppression of KV2.1 by activation of the AKAP150-CaN/NFATc3 signaling axis contributes to enhanced arterial tone during diabetes.
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Affiliation(s)
| | - Matthew A Nystoriak
- From the Department of Pharmacology, University of California, Davis, California 95616
| | - Maria Paz Prada
- From the Department of Pharmacology, University of California, Davis, California 95616
| | - Kenneth Johnson
- From the Department of Pharmacology, University of California, Davis, California 95616
| | - William Fayer
- From the Department of Pharmacology, University of California, Davis, California 95616
| | - Mark L Dell'Acqua
- the Department of Pharmacology, University of Colorado, Denver, Colorado 80045, and
| | - John D Scott
- the Howard Hughes Medical Institute and Department of Pharmacology, University of Washington, Seattle, Washington 98195
| | - Manuel F Navedo
- From the Department of Pharmacology, University of California, Davis, California 95616,
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Tamura K, Ohki K, Kobayashi R, Uneda K, Azushima K, Ohsawa M, Wakui H, Umemura S. Fetal programming by high-sucrose diet during pregnancy affects the vascular angiotensin II receptor–PKC–L-type Ca2+ channels (Cav1.2) axis to enhance pressor responses. Hypertens Res 2014; 37:796-8. [DOI: 10.1038/hr.2014.105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Harraz OF, Altier C. STIM1-mediated bidirectional regulation of Ca(2+) entry through voltage-gated calcium channels (VGCC) and calcium-release activated channels (CRAC). Front Cell Neurosci 2014; 8:43. [PMID: 24605083 PMCID: PMC3932444 DOI: 10.3389/fncel.2014.00043] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 01/29/2014] [Indexed: 11/13/2022] Open
Abstract
The spatial and temporal regulation of cellular calcium signals is modulated via two main Ca(2+) entry routes. Voltage-gated Ca(2+) channels (VGCC) and Ca(2+)-release activated channels (CRAC) enable Ca(2+) flow into electrically excitable and non-excitable cells, respectively. VGCC are well characterized transducers of electrical activity that allow Ca(2+) signaling into the cell in response to action potentials or subthreshold depolarizing stimuli. The identification of STromal Interaction Molecule (STIM) and Orai proteins has provided significant insights into the understanding of CRAC function and regulation. This review will summarize the current state of knowledge of STIM-Orai interaction and their contribution to cellular Ca(2+) handling mechanisms. We will then discuss the bidirectional actions of STIM1 on VGCC and CRAC. In contrast to the stimulatory role of STIM1 on Orai channel activity that facilitates Ca(2+) entry, recent reports indicated the ability of STIM1 to suppress VGCC activity. This new concept changes our traditional understanding of Ca(2+) handling mechanisms and highlights the existence of dynamically regulated signaling complexes of surface expressed ion channels and intracellular store membrane-embedded Ca(2+) sensors. Overall, STIM1 is emerging as a new class of regulatory proteins that fine-tunes Ca(2+) entry in response to endoplasmic/sarcoplasmic reticulum stress.
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Affiliation(s)
- Osama F Harraz
- Department of Physiology and Pharmacology, Hotchkiss Brain Institute, Libin Cardiovascular Institute, University of Calgary Calgary, AB, Canada ; Department of Pharmacology and Toxicology, Faculty of Pharmacy, Alexandria University Alexandria, Egypt
| | - Christophe Altier
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Inflammation Research Network, University of Calgary Calgary, AB, Canada
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