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Aggarwal A, Sunil S, Bendifallah I, Moon M, Drobizhev M, Zarowny L, Zheng J, Wu SY, Lohman AW, Tebo AG, Emiliani V, Podgorski K, Shen Y, Campbell RE. Blue-shifted genetically encoded Ca 2+ indicator with enhanced two-photon absorption. Neurophotonics 2024; 11:024207. [PMID: 38577628 PMCID: PMC10993905 DOI: 10.1117/1.nph.11.2.024207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 04/06/2024]
Abstract
Significance Genetically encoded calcium ion (Ca 2 + ) indicators (GECIs) are powerful tools for monitoring intracellular Ca 2 + concentration changes in living cells and model organisms. In particular, GECIs have found particular utility for monitoring the transient increase of Ca 2 + concentration that is associated with the neuronal action potential. However, the palette of highly optimized GECIs for imaging of neuronal activity remains relatively limited. Expanding the selection of available GECIs to include new colors and distinct photophysical properties could create new opportunities for in vitro and in vivo fluorescence imaging of neuronal activity. In particular, blue-shifted variants of GECIs are expected to have enhanced two-photon brightness, which would facilitate multiphoton microscopy. Aim We describe the development and applications of T-GECO1-a high-performance blue-shifted GECI based on the Clavularia sp.-derived mTFP1. Approach We use protein engineering and extensive directed evolution to develop T-GECO1. We characterize the purified protein and assess its performance in vitro using one-photon excitation in cultured rat hippocampal neurons, in vivo using one-photon excitation fiber photometry in mice, and ex vivo using two-photon Ca 2 + imaging in hippocampal slices. Results The Ca 2 + -bound state of T-GECO1 has an excitation peak maximum of 468 nm, an emission peak maximum of 500 nm, an extinction coefficient of 49,300 M - 1 cm - 1 , a quantum yield of 0.83, and two-photon brightness approximately double that of EGFP. The Ca 2 + -dependent fluorescence increase is 15-fold, and the apparent K d for Ca 2 + is 82 nM. With two-photon excitation conditions at 850 nm, T-GECO1 consistently enabled the detection of action potentials with higher signal-to-noise (SNR) than a late generation GCaMP variant. Conclusions T-GECO1 is a high-performance blue-shifted GECI that, under two-photon excitation conditions, provides advantages relative to late generation GCaMP variants.
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Affiliation(s)
- Abhi Aggarwal
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Allen Institute for Neural Dynamics, Seattle, Washington, United States
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
- University of Calgary, Hotchkiss Brain Institute, Department of Cell Biology and Anatomy Calgary, Alberta, Canada
| | - Smrithi Sunil
- Allen Institute for Neural Dynamics, Seattle, Washington, United States
| | | | - Michael Moon
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Mikhail Drobizhev
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, Montana, United States
| | - Landon Zarowny
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Jihong Zheng
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
| | - Sheng-Yi Wu
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Alexander W. Lohman
- University of Calgary, Hotchkiss Brain Institute, Department of Cell Biology and Anatomy Calgary, Alberta, Canada
| | - Alison G. Tebo
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
| | | | - Kaspar Podgorski
- Allen Institute for Neural Dynamics, Seattle, Washington, United States
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States
| | - Yi Shen
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Robert E. Campbell
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Université Laval, CERVO Brain Research Center, Department of Biochemistry, Microbiology, and Bioinformatics, Québec, Québec, Canada
- University of Tokyo, Department of Chemistry, Tokyo, Japan
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2
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Aggarwal A, Sunil S, Bendifallah I, Moon M, Drobizhev M, Zarowny L, Zheng J, Wu SY, Lohman AW, Tebo AG, Emiliani V, Podgorski K, Shen Y, Campbell RE. A blue-shifted genetically encoded Ca 2+ indicator with enhanced two-photon absorption. bioRxiv 2023:2023.10.12.562058. [PMID: 37905143 PMCID: PMC10614751 DOI: 10.1101/2023.10.12.562058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Significance Genetically encoded calcium ion (Ca2+) indicators (GECIs) are powerful tools for monitoring intracellular Ca2+ concentration changes in living cells and model organisms. In particular, GECIs have found particular utility for monitoring the transient increase of Ca2+ concentration that is associated with the neuronal action potential. However, the palette of highly optimized GECIs for imaging of neuronal activity remains relatively limited. Expanding the selection of available GECIs to include new colors and distinct photophysical properties could create new opportunities for in vitro and in vivo fluorescence imaging of neuronal activity. In particular, blue-shifted variants of GECIs are expected to have enhanced two-photon brightness, which would facilitate multiphoton microscopy. Aim We describe the development and applications of T-GECO1 - a high-performance blue-shifted GECI based on the Clavularia sp.-derived mTFP1. Approach We used protein engineering and extensive directed evolution to develop T-GECO1. We characterize the purified protein and assess its performance in vitro using one-photon excitation in cultured rat hippocampal neurons, in vivo using one-photon excitation fiber photometry in mice, and ex vivo using two-photon Ca2+ imaging in hippocampal slices. Results The Ca2+-bound state of T-GECO1 has an excitation peak maximum of 468 nm, an emission peak maximum of 500 nm, an extinction coefficient of 49,300 M-1cm-1, a quantum yield of 0.83, and two-photon brightness approximately double that of EGFP. The Ca2+-dependent fluorescence increase is 15-fold and the apparent Kd for Ca2+ is 82 nM. With two-photon excitation conditions at 850 nm, T-GECO1 consistently enabled detection of action potentials with higher signal-to-noise (SNR) than a late generation GCaMP variant. Conclusion T-GECO1 is a high performance blue-shifted GECI that, under two-photon excitation conditions, provides advantages relative to late generation GCaMP variants.
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Affiliation(s)
- Abhi Aggarwal
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Allen Institute for Neural Dynamics, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
- University of Calgary, Department of Cell Biology and Anatomy and Hotchkiss Brain Institute, Calgary, Alberta, Canada
| | - Smrithi Sunil
- Allen Institute for Neural Dynamics, Seattle, Washington, United States of America
| | | | - Michael Moon
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Mikhail Drobizhev
- Montana State University, Department of Microbiology and Cell Biology, Bozeman, Montana, United States of America
| | - Landon Zarowny
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Jihong Zheng
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | - Sheng-Yi Wu
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Alexander W. Lohman
- University of Calgary, Department of Cell Biology and Anatomy and Hotchkiss Brain Institute, Calgary, Alberta, Canada
| | - Alison G. Tebo
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | | | - Kaspar Podgorski
- Allen Institute for Neural Dynamics, Seattle, Washington, United States of America
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, Virginia, United States of America
| | - Yi Shen
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
| | - Robert E. Campbell
- University of Alberta, Department of Chemistry, Edmonton, Alberta, Canada
- Université Laval, CERVO Brain Research Center and Department of Biochemistry, Microbiology, and Bioinformatics, Québec, Québec, Canada
- The University of Tokyo, Department of Chemistry, Bunkyo-ku, Tokyo, Japan
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Eyolfson E, Carr T, Fraunberger E, Khan A, Clark I, Mychasiuk R, Lohman AW. Repeated mild traumatic brain injuries in mice cause age- and sex-specific alterations in dendritic spine density. Exp Neurol 2022; 357:114172. [PMID: 35863503 DOI: 10.1016/j.expneurol.2022.114172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/08/2022] [Accepted: 07/14/2022] [Indexed: 11/25/2022]
Abstract
Mild traumatic brain injuries (mTBI) plague the human population and their prevalence is increasing annually. More so, repeated mTBIs (RmTBI) are known to manifest and compound neurological deficits in vulnerable populations. Age at injury and sex are two important factors influencing RmTBI pathophysiology, but we continue to know little about the specific effects of RmTBI in youth and females. In this study, we directly quantified the effects of RmTBI on adolescent and adult, male and female mice, with a closed-head lateral impact model. We report age- and sex-specific neurobehavioural deficits in motor function and working memory, microglia responses to injury, and the subsequent changes in dendritic spine density in select brain regions. Specifically, RmTBI caused increased footslips in adult male mice as assessed in a beam walk assay and significantly reduced the time spent with a novel object in adolescent male and female mice. RmTBIs caused a significant reduction in microglia density in male mice in the motor cortex, but not female mice. Finally, RmTBI significantly reduced dendritic spine density in the agranular insular cortex (a region of the prefrontal cortex in mice) and increased dendritic spine density in the adolescent male motor cortex. Together, the data provided in this study sheds new light on the heterogeneity in RmTBI-induced behavioural, glial, and neuronal architecture changes dependent on age and sex.
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Affiliation(s)
- Eric Eyolfson
- Department of Psychology, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada.
| | - Thomas Carr
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Erik Fraunberger
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Asher Khan
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Isabel Clark
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
| | - Richelle Mychasiuk
- Department of Psychology, University of Calgary, Calgary, AB, Canada; Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada; Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, Australia.
| | - Alexander W Lohman
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, AB, Canada; Department of Cell Biology and Anatomy, University of Calgary, Calgary, AB, Canada; Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, AB, Canada.
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Koval M, Cwiek A, Carr T, Good ME, Lohman AW, Isakson BE. Pannexin 1 as a driver of inflammation and ischemia-reperfusion injury. Purinergic Signal 2021; 17:521-531. [PMID: 34251590 PMCID: PMC8273370 DOI: 10.1007/s11302-021-09804-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 06/24/2021] [Indexed: 02/06/2023] Open
Abstract
Pannexin 1 (Panx1) is a ubiquitously expressed protein forming large conductance channels that are central to many distinct inflammation and injury responses. There is accumulating evidence showing ATP released from Panx1 channels, as well as metabolites, provide effective paracrine and autocrine signaling molecules that regulate different elements of the injury response. As channels with a broad range of permselectivity, Panx1 channels mediate the secretion and uptake of multiple solutes, ranging from calcium to bacterial derived molecules. In this review, we describe how Panx1 functions in response to different pro-inflammatory stimuli, focusing mainly on signaling coordinated by the vasculature. How Panx1 mediates ATP release by injured cells is also discussed. The ability of Panx1 to serve as a central component of many diverse physiologic responses has proven to be critically dependent on the context of expression, post-translational modification, interacting partners, and the mode of stimulation.
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Affiliation(s)
- Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, 205 Whitehead Building, 615 Michael Street, Atlanta, GA, 30322, USA. .,Department of Cell Biology, Emory University School of Medicine, Atlanta, GA, 30322, USA.
| | - Aleksandra Cwiek
- Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA
| | - Thomas Carr
- Department of Cell Biology and Anatomy, University of Calgary Cumming School of Medicine, Calgary, AB, Canada.,Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Miranda E Good
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA, USA
| | - Alexander W Lohman
- Department of Cell Biology and Anatomy, University of Calgary Cumming School of Medicine, Calgary, AB, Canada.,Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, School of Medicine, University of Virginia, PO Box 801394, Charlottesville, VA, 22908, USA. .,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA, 22908, USA.
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5
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Soria-Gomez E, Pagano Zottola AC, Mariani Y, Desprez T, Barresi M, Bonilla-del Río I, Muguruza C, Le Bon-Jego M, Julio-Kalajzić F, Flynn R, Terral G, Fernández-Moncada I, Robin LM, Oliveira da Cruz JF, Corinti S, Amer YO, Goncalves J, Varilh M, Cannich A, Redon B, Zhao Z, Lesté-Lasserre T, Vincent P, Tolentino-Cortes T, Busquets-García A, Puente N, Bains JS, Hebert-Chatelain E, Barreda-Gómez G, Chaouloff F, Lohman AW, Callado LF, Grandes P, Baufreton J, Marsicano G, Bellocchio L. Subcellular specificity of cannabinoid effects in striatonigral circuits. Neuron 2021; 109:1513-1526.e11. [DOI: 10.1016/j.neuron.2021.03.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 02/09/2021] [Accepted: 03/04/2021] [Indexed: 12/14/2022]
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6
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Eyolfson E, Bhatt D, Wang M, Lohman AW, Mychasiuk R. Paternal exposure to exercise and/or caffeine and alcohol modify offspring behavioral and pathophysiological recovery from repetitive mild traumatic brain injury in adolescence. Genes Brain Behav 2021; 20:egbb12736. [PMID: 33876557 DOI: 10.1111/gbb.12736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/16/2021] [Accepted: 04/17/2021] [Indexed: 11/30/2022]
Abstract
Only recently has the scope of parental research expanded to include the paternal sphere with epidemiological studies implicating stress, nutrition and alcohol consumption in the neurobiological and behavioral characteristics of offspring. This study was designed to determine if paternal exposure to caffeine, alcohol and exercise prior to conception would improve or exacerbate offspring recovery from adolescent repetitive mild traumatic brain injury (RmTBI). Sires received 7 weeks of standard drinking water, or caffeine and ethanol and were housed in regular cages or cages with running wheels, prior to being mated to control females. At postnatal day 40, offspring were administered RmTBI or sham injuries and were assessed for post concussive symptomology. Post-mortem quantitative real-time polymerase chain reaction (qRT-PCR) was used to assess gene expression in the prefrontal cortex (PFC), nucleus accumbens (NAc) and changes in telomere length. Additionally, enzyme-linked immunosorbent assay (ELISA's) were run on serum to detect levels of cytokines, chemokines and sex hormones. Paternal experience did not improve or exacerbate RmTBI behavioral outcomes. However, female and male offspring displayed unique responses to RmTBI and paternal experience, resulting in changes in physical, behavioral and molecular outcomes. Injury and paternal exercise modified changes in female offspring, whereas male offspring were affected by paternal exercise, caffeine and alcohol treatment. Additionally, paternal experience and RmTBI modified expression of many genes in the PFC, NAc, telomere length and levels of sex hormones. Although further exploration is required to understand the heterogeneity that exists in disease risk and resiliency, this study provides corroborating evidence that paternal experiences prior to conception influences offspring development.
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Affiliation(s)
- Eric Eyolfson
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
| | - Dhyey Bhatt
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Melinda Wang
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
| | - Alexander W Lohman
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Richelle Mychasiuk
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
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7
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Gom RC, Bhatt D, Villa BR, George AG, Lohman AW, Mychasiuk R, Rho JM, Teskey GC. The ketogenic diet raises brain oxygen levels, attenuates postictal hypoxia, and protects against learning impairments. Neurobiol Dis 2021; 154:105335. [PMID: 33741453 DOI: 10.1016/j.nbd.2021.105335] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 02/26/2021] [Accepted: 03/14/2021] [Indexed: 10/21/2022] Open
Abstract
OBJECTIVES A prolonged vasoconstriction/hypoperfusion/hypoxic event follows self-terminating focal seizures. The ketogenic diet (KD) has demonstrated efficacy as a metabolic treatment for intractable epilepsy and other disorders but its effect on local brain oxygen levels is completely unknown. This study investigated the effects of the KD on tissue oxygenation in the hippocampus before and after electrically elicited (kindled) seizures and whether it could protect against a seizure-induced learning impairment. We also examined the effects of the ketone β-hydroxybutyrate (BHB) as a potential underlying mechanism. METHODS Male and female rats were given access to one of three diet protocols 2 weeks prior to the initiation of seizures: KD, caloric restricted standard chow, and ad libitum standard chow. Dorsal hippocampal oxygen levels were measured prior to initiation of diets as well as before and after a 10-day kindling paradigm. Male rats were then tested on a novel object recognition task to assess postictal learning impairments. In a separate cohort, BHB was administered 30 min prior to seizure elicitation to determine whether it influenced oxygen dynamics. RESULTS The KD increased dorsal hippocampal oxygen levels, ameliorated postictal hypoxia, and prevented postictal learning impairments. Acute BHB administration did not alter oxygen levels before or after seizures. INTERPRETATION The ketogenic diet raised brain oxygen levels and attenuated severe postictal hypoxia likely through a mechanism independent of ketosis and shows promise as a non-pharmacological treatment to prevent the postictal state.
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Affiliation(s)
- Renaud C Gom
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, CA, Canada.
| | - Dhyey Bhatt
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, CA, Canada
| | - Bianca R Villa
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, CA, Canada
| | - Antis G George
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, CA, Canada
| | - Alexander W Lohman
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, CA, Canada
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Australia
| | - Jong M Rho
- Department of Pediatrics, Alberta Children's Hospital Research Institute, Cumming School of Medicine University of Calgary, Calgary, CA, Canada; Departments of Neurosciences and Pediatrics, University of California San Diego, Rady Children's Hospital San Diego, California, USA
| | - G Campbell Teskey
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, and Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, Calgary, CA, Canada
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8
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Maier-Begandt D, Comstra HS, Molina SA, Krüger N, Ruddiman CA, Chen YL, Chen X, Biwer LA, Johnstone SR, Lohman AW, Good ME, DeLalio LJ, Hong K, Bacon HM, Yan Z, Sonkusare SK, Koval M, Isakson BE. A venous-specific purinergic signaling cascade initiated by Pannexin 1 regulates TNFα-induced increases in endothelial permeability. Sci Signal 2021; 14:14/672/eaba2940. [PMID: 33653920 PMCID: PMC8011850 DOI: 10.1126/scisignal.aba2940] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The endothelial cell barrier regulates the passage of fluid between the bloodstream and underlying tissues, and barrier function impairment exacerbates the severity of inflammatory insults. To understand how inflammation alters vessel permeability, we studied the effects of the proinflammatory cytokine TNFα on transendothelial permeability and electrophysiology in ex vivo murine veins and arteries. We found that TNFα specifically decreased the barrier function of venous endothelium without affecting that of arterial endothelium. On the basis of RNA expression profiling and protein analysis, we found that claudin-11 (CLDN11) was the predominant claudin in venous endothelial cells and that there was little, if any, CLDN11 in arterial endothelial cells. Consistent with a difference in claudin composition, TNFα increased the permselectivity of Cl- over Na+ in venous but not arterial endothelium. The vein-specific effects of TNFα also required the activation of Pannexin 1 (Panx1) channels and the CD39-mediated hydrolysis of ATP to adenosine, which subsequently stimulated A2A adenosine receptors. Moreover, the increase in vein permeability required the activation of the Ca2+ channel TRPV4 downstream of Panx1 activation. Panx1-deficient mice resisted the pathologic effects of sepsis induced by cecal ligation and puncture on life span and lung vascular permeability. These data provide a targetable pathway with the potential to promote vein barrier function and prevent the deleterious effects of vascular leak in response to inflammation.
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Affiliation(s)
- Daniela Maier-Begandt
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.,Walter Brendel Center of Experimental Medicine, University Hospital, and Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, 82152 Planegg-Martinsried, Germany
| | - Heather Skye Comstra
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Samuel A Molina
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Nenja Krüger
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.,Institute of Animal Developmental and Molecular Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Claire A Ruddiman
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Yen-Lin Chen
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Xiaobin Chen
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Lauren A Biwer
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Scott R Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion Center for Heart and Reparative Medicine Research, Virginia Tech, Roanoke, VA 24016, USA.,Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
| | - Alexander W Lohman
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Miranda E Good
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA 02111, USA
| | - Leon J DeLalio
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Kwangseok Hong
- Department of Physical Education, College of Education, Chung-Ang University, Seoul 06974, South Korea
| | - Hannah M Bacon
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Zhen Yan
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Swapnil K Sonkusare
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Michael Koval
- Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA. .,Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA. .,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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9
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Eyolfson E, Carr T, Khan A, Wright DK, Mychasiuk R, Lohman AW. Repetitive Mild Traumatic Brain Injuries in Mice during Adolescence Cause Sexually Dimorphic Behavioral Deficits and Neuroinflammatory Dynamics. J Neurotrauma 2020; 37:2718-2732. [DOI: 10.1089/neu.2020.7195] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Affiliation(s)
- Eric Eyolfson
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, Alberta, Canada
| | - Thomas Carr
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, Alberta, Canada
| | - Asher Khan
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, Alberta, Canada
| | - David K. Wright
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Richelle Mychasiuk
- Department of Psychology, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, Alberta, Canada
- Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, Alberta, Canada
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Alexander W. Lohman
- Alberta Children's Hospital Research Institute (ACHRI), Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute (HBI), University of Calgary, Calgary, Alberta, Canada
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10
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Abstract
Repetitive, mild traumatic brain injuries (RmTBIs) are increasingly common in adolescents and encompass one of the largest neurological health concerns in the world. Adolescence is a critical period for brain development where RmTBIs can substantially impact neurodevelopmental trajectories and life-long neurological health. Our current understanding of RmTBI pathophysiology suggests key roles for neuroinflammation in negatively regulating neural health and function. Microglia, the brain’s resident immune population, play important roles in brain development by regulating neuronal number, and synapse formation and elimination. In response to injury, microglia activate to inflammatory phenotypes that may detract from these normal homeostatic, physiological, and developmental roles. To date, however, little is known regarding the impact of RmTBIs on microglia function during adolescent brain development. This review details key concepts surrounding RmTBI pathophysiology, adolescent brain development, and microglia dynamics in the developing brain and in response to injury, in an effort to formulate a hypothesis on how the intersection of these processes may modify long-term trajectories.
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Affiliation(s)
- Eric Eyolfson
- Department of Psychology, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N1N4, Canada.,Hotchkiss Brain Institute, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N4N1, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, NW, Calgary, AB, T2N4N1, Canada
| | - Asher Khan
- Hotchkiss Brain Institute, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N4N1, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, NW, Calgary, AB, T2N4N1, Canada
| | - Richelle Mychasiuk
- Department of Psychology, University of Calgary, 2500 University Drive NW, Calgary, AB, T2N1N4, Canada.,Hotchkiss Brain Institute, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N4N1, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, NW, Calgary, AB, T2N4N1, Canada.,Department of Neuroscience, Monash University, 6th Floor, The Alfred Centre, 99 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Alexander W Lohman
- Hotchkiss Brain Institute, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N4N1, Canada. .,Alberta Children's Hospital Research Institute, University of Calgary, 3330 Hospital Drive, NW, Calgary, AB, T2N4N1, Canada. .,Department of Cell Biology and Anatomy, University of Calgary, 3330 Hospital Drive NW, Calgary, AB, T2N4N1, Canada.
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11
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Swayne LA, Johnstone SR, Ng CS, Sanchez-Arias JC, Good ME, Penuela S, Lohman AW, Wolpe AG, Laubach VE, Koval M, Isakson BE. Consideration of Pannexin 1 channels in COVID-19 pathology and treatment. Am J Physiol Lung Cell Mol Physiol 2020; 319:L121-L125. [PMID: 32519892 PMCID: PMC7347959 DOI: 10.1152/ajplung.00146.2020] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Leigh Anne Swayne
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Scott R Johnstone
- Fralin Biomedical Research Institute at Virginia Tech Carilion Center for Heart and Reparative Medicine Research, Virginia Tech, Roanoke, Virginia.,Department of Biological Sciences, Virginia Tech, Roanoke, Virginia
| | - Chen Seng Ng
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Centre for Heart Lung Innovation, St. Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Juan C Sanchez-Arias
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Miranda E Good
- Molecular Cardiology Research Institute, Tufts Medical Center, Boston, Massachusetts
| | - Silvia Penuela
- Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada
| | - Alexander W Lohman
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Abigail G Wolpe
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia.,Department of Cell Biology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Victor E Laubach
- Department of Surgery, University of Virginia School of Medicine, Charlottesville, Virginia.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Michael Koval
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care and Sleep Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia
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12
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Eyolfson E, Yamakawa GR, Griep Y, Collins R, Carr T, Wang M, Lohman AW, Mychasiuk R. Examining the Progressive Behavior and Neuropathological Outcomes Associated with Chronic Repetitive Mild Traumatic Brain Injury in Rats. Cereb Cortex Commun 2020; 1:tgaa002. [PMID: 34296084 PMCID: PMC8152839 DOI: 10.1093/texcom/tgaa002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/24/2020] [Accepted: 01/30/2020] [Indexed: 02/07/2023] Open
Abstract
While the physical and behavioral symptomologies associated with a single mild traumatic brain injury (mTBI) are typically transient, repetitive mTBIs (RmTBI) have been associated with persisting neurological deficits. Therefore, this study examined the progressive changes in behavior and the neuropathological outcomes associated with chronic RmTBI through adolescence and adulthood in male and female Sprague Dawley rats. Rats experienced 2 mTBIs/week for 15 weeks and were periodically tested for changes in motor behavior, cognitive function, emotional disturbances, and aggression. Brain tissue was examined for neuropathological changes in ventricle size and presentation of Iba1 and GFAP. We did not see progressively worse behavioral impairments with the accumulation of injuries or time, but did find evidence for neurological and functional change (motor disturbance, reduced exploration, reduced aggression, alteration in depressive-like behavior, deficits in short-term working memory). Neuropathological assessment of RmTBI animals identified an increase in ventricle size, prolonged changes in GFAP, and sex differences in Iba1, in the corpus callosum, thalamus, and medial prefrontal cortex. Telomere length reduced exponentially as the injury load increased. Overall, chronic RmTBI did not result in accumulating behavioral impairment, and there is a need to further investigate progressive behavioral changes associated with repeated injuries in adolescence and young adulthood.
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Affiliation(s)
- Eric Eyolfson
- Department of Psychology, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Psychology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Glenn R Yamakawa
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Yannick Griep
- Department of Psychology, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Psychology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Division of Epidemiology, Stress Research Institute, Stockholm University, 106 91 Stockholm, Sweden
- Behavioral Science Institute, Radbound University, 9104, 6500 HE, Nijmegen, The Netherlands
| | - Reid Collins
- Department of Psychology, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Psychology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Thomas Carr
- Department of Cell Biology and Anatomy, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Melinda Wang
- Department of Psychology, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Psychology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Alexander W Lohman
- Department of Cell Biology and Anatomy, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
| | - Richelle Mychasiuk
- Department of Psychology, Alberta Children’s Hospital Research Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Psychology, Hotchkiss Brain Institute, The University of Calgary, Calgary, AB, T2N 1N4, Canada
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
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13
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DeLalio LJ, Billaud M, Ruddiman CA, Johnstone SR, Butcher JT, Wolpe AG, Jin X, Keller TCS, Keller AS, Rivière T, Good ME, Best AK, Lohman AW, Swayne LA, Penuela S, Thompson RJ, Lampe PD, Yeager M, Isakson BE. Constitutive SRC-mediated phosphorylation of pannexin 1 at tyrosine 198 occurs at the plasma membrane. J Biol Chem 2019; 294:6940-6956. [PMID: 30814251 DOI: 10.1074/jbc.ra118.006982] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/15/2019] [Indexed: 11/06/2022] Open
Abstract
Pannexin 1 (PANX1)-mediated ATP release in vascular smooth muscle coordinates α1-adrenergic receptor (α1-AR) vasoconstriction and blood pressure homeostasis. We recently identified amino acids 198-200 (YLK) on the PANX1 intracellular loop that are critical for α1-AR-mediated vasoconstriction and PANX1 channel function. We report herein that the YLK motif is contained within an SRC homology 2 domain and is directly phosphorylated by SRC proto-oncogene, nonreceptor tyrosine kinase (SRC) at Tyr198 We demonstrate that PANX1-mediated ATP release occurs independently of intracellular calcium but is sensitive to SRC family kinase (SFK) inhibition, suggestive of channel regulation by tyrosine phosphorylation. Using a PANX1 Tyr198-specific antibody, SFK inhibitors, SRC knockdown, temperature-dependent SRC cells, and kinase assays, we found that PANX1-mediated ATP release and vasoconstriction involves constitutive phosphorylation of PANX1 Tyr198 by SRC. We specifically detected SRC-mediated Tyr198 phosphorylation at the plasma membrane and observed that it is not enhanced or induced by α1-AR activation. Last, we show that PANX1 immunostaining is enriched in the smooth muscle layer of arteries from hypertensive humans and that Tyr198 phosphorylation is detectable in these samples, indicative of a role for membrane-associated PANX1 in small arteries of hypertensive humans. Our discovery adds insight into the regulation of PANX1 by post-translational modifications and connects a significant purinergic vasoconstriction pathway with a previously identified, yet unexplored, tyrosine kinase-based α1-AR constriction mechanism. This work implicates SRC-mediated PANX1 function in normal vascular hemodynamics and suggests that Tyr198-phosphorylated PANX1 is involved in hypertensive vascular pathology.
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Affiliation(s)
- Leon J DeLalio
- From the Robert M. Berne Cardiovascular Research Center.,Department of Pharmacology
| | - Marie Billaud
- the Department of Cardiothoracic Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15213
| | - Claire A Ruddiman
- From the Robert M. Berne Cardiovascular Research Center.,Department of Pharmacology
| | | | - Joshua T Butcher
- the Department of Physiology, Augusta University, Augusta, Georgia 30912
| | - Abigail G Wolpe
- From the Robert M. Berne Cardiovascular Research Center.,Department of Cell Biology, and
| | - Xueyao Jin
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - T C Stevenson Keller
- From the Robert M. Berne Cardiovascular Research Center.,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - Alexander S Keller
- From the Robert M. Berne Cardiovascular Research Center.,Department of Pharmacology
| | - Thibaud Rivière
- the Department of Life and Health Sciences, University of Bordeaux, 33000 Bordeaux, France
| | | | - Angela K Best
- From the Robert M. Berne Cardiovascular Research Center
| | - Alexander W Lohman
- the Hotchkiss Brain Institute and.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Leigh Anne Swayne
- the Division of Medical Sciences, Centre for Biomedical Research, University of Victoria, Victoria, British Columbia V8P 5C2, Canada
| | - Silvia Penuela
- the Departments of Anatomy and Cell Biology and Oncology, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario N6A 3K7, Canada, and
| | - Roger J Thompson
- the Hotchkiss Brain Institute and.,Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Paul D Lampe
- the Fred Hutchinson Cancer Research Center, Seattle, Washington 98109
| | - Mark Yeager
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
| | - Brant E Isakson
- From the Robert M. Berne Cardiovascular Research Center, .,Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, Virginia 22908
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14
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Good ME, Chiu YH, Poon IKH, Medina CB, Butcher JT, Mendu SK, DeLalio LJ, Lohman AW, Leitinger N, Barrett E, Lorenz UM, Desai BN, Jaffe IZ, Bayliss DA, Isakson BE, Ravichandran KS. Pannexin 1 Channels as an Unexpected New Target of the Anti-Hypertensive Drug Spironolactone. Circ Res 2017; 122:606-615. [PMID: 29237722 DOI: 10.1161/circresaha.117.312380] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 12/06/2017] [Accepted: 12/12/2017] [Indexed: 12/16/2022]
Abstract
RATIONALE Resistant hypertension is a major health concern with unknown cause. Spironolactone is an effective antihypertensive drug, especially for patients with resistant hypertension, and is considered by the World Health Organization as an essential medication. Although spironolactone can act at the mineralocorticoid receptor (MR; NR3C2), there is increasing evidence of MR-independent effects of spironolactone. OBJECTIVE Here, we detail the unexpected discovery that Panx1 (pannexin 1) channels could be a relevant in vivo target of spironolactone. METHODS AND RESULTS First, we identified spironolactone as a potent inhibitor of Panx1 in an unbiased small molecule screen, which was confirmed by electrophysiological analysis. Next, spironolactone inhibited α-adrenergic vasoconstriction in arterioles from mice and hypertensive humans, an effect dependent on smooth muscle Panx1, but independent of the MR NR3C2. Last, spironolactone acutely lowered blood pressure, which was dependent on smooth muscle cell expression of Panx1 and independent of NR3C2. This effect, however, was restricted to steroidal MR antagonists as a nonsteroidal MR antagonist failed to reduced blood pressure. CONCLUSIONS These data suggest new therapeutic modalities for resistant hypertension based on Panx1 inhibition.
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Affiliation(s)
- Miranda E Good
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Yu-Hsin Chiu
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Ivan K H Poon
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Christopher B Medina
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Joshua T Butcher
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Suresh K Mendu
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Leon J DeLalio
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Alexander W Lohman
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Norbert Leitinger
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Eugene Barrett
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Ulrike M Lorenz
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Bimal N Desai
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Iris Z Jaffe
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Douglas A Bayliss
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
| | - Brant E Isakson
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.).
| | - Kodi S Ravichandran
- From the Department of Molecular Physiology and Biophysics, Robert M. Berne Cardiovascular Research Center (M.E.G., J.T.B., L.J.D., A.W.L., B.E.I.), Department of Pharmacology (Y.-H.C., S.K.M., N.L., B.N.D., D.A.B.), Department of Microbiology, Immunology and Cancer Biology, the Center for Cell Clearance, and the Beirne B. Carter Center for Immunology Research (C.B.M., U.M.L., K.S.R.), and Division of Endocrinology (E.B.), University of Virginia School of Medicine, Charlottesville; Department of Biochemistry and Genetics, La Trobe University, Melbourne, Australia (I.K.H.P.); and Molecular Cardiology Research Institute, Tufts Medical Center, Boston, MA (I.Z.J.)
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15
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Lohman AW, Weilinger NL, Santos SM, Bialecki J, Werner AC, Anderson CL, Thompson RJ. Regulation of pannexin channels in the central nervous system by Src family kinases. Neurosci Lett 2017; 695:65-70. [PMID: 28911820 DOI: 10.1016/j.neulet.2017.09.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 07/24/2017] [Accepted: 09/10/2017] [Indexed: 02/06/2023]
Abstract
Pannexins form single membrane channels that regulate the passage of ions, small molecules and metabolites between the intra- and extracellular compartments. In the central nervous system, these channels are integrated into numerous signaling cascades that shape brain physiology and pathology. Post-translational modification of pannexins is complex, with phosphorylation emerging as a prominent form of functional regulation. While much is still not known regarding the specific kinases and modified amino acids, recent reports support a role for Src family tyrosine kinases (SFK) in regulating pannexin channel activity. This review outlines the current evidence supporting SFK-dependent pannexin phosphorylation in the CNS and examines the importance of these modifications in the healthy and diseased brain.
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Affiliation(s)
- Alexander W Lohman
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Nicholas L Weilinger
- Djavad Mowafaghian Centre for Brain Health, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Silva Mf Santos
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Jennifer Bialecki
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Allison C Werner
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Connor L Anderson
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Roger J Thompson
- Department of Cell Biology and Anatomy, University of Calgary, Calgary, Alberta, Canada; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.
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16
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Zhang W, Lohman AW, Zhuravlova Y, Lu X, Wiens MD, Hoi H, Yaganoglu S, Mohr MA, Kitova EN, Klassen JS, Pantazis P, Thompson RJ, Campbell RE. Optogenetic control with a photocleavable protein, PhoCl. Nat Methods 2017; 14:391-394. [PMID: 28288123 DOI: 10.1038/nmeth.4222] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/14/2017] [Indexed: 11/08/2022]
Abstract
To expand the range of experiments that are accessible with optogenetics, we developed a photocleavable protein (PhoCl) that spontaneously dissociates into two fragments after violet-light-induced cleavage of a specific bond in the protein backbone. We demonstrated that PhoCl can be used to engineer light-activatable Cre recombinase, Gal4 transcription factor, and a viral protease that in turn was used to activate opening of the large-pore ion channel Pannexin-1.
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Affiliation(s)
- Wei Zhang
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Alexander W Lohman
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | | | - Xiaocen Lu
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Matthew D Wiens
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Hiofan Hoi
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Sine Yaganoglu
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Manuel A Mohr
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Elena N Kitova
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
- Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, Canada
| | - John S Klassen
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
- Alberta Glycomics Centre, University of Alberta, Edmonton, Alberta, Canada
| | - Periklis Pantazis
- Department of Biosystems Science and Engineering, ETH Zürich, Basel, Switzerland
| | - Roger J Thompson
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Department of Cell Biology and Anatomy, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Robert E Campbell
- Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada
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17
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Abstract
All connexins (Cx) proteins contain both highly ordered domains (i.e., 4 transmembrane domains) and primarily unstructured regions (i.e., n- and c-terminal domains). The c-terminal domains vary in length and amino acid composition from the shortest on Cx26 to the longest on Cx43. With the exception of Cx26, the c-terminal domains contain multiple sites for posttranslational modification (PTM) including serines (S), threonines (T), and tyrosines (Y) for phosphorylation or cysteines (C) for S-nitrosylation. These PTMs are critical for regulating cellular localization, protein-protein interactions, and channel functionality. There are several biochemical techniques that allow for the identification of these PTM including Western blotting and the "Biotin Switch" assay for nitrosylation. Quantitative analysis of Western blots can be achieved through use of secondary antibodies in the near infrared scale and high-resolution scanning on a fluorescent scanner.
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Affiliation(s)
- Alexander W Lohman
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada, T2N 4N1
| | - Adam C Straub
- Department of Pharmacology and Chemical Biology, Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh, Pittsburgh, PA, USA
| | - Scott R Johnstone
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.
- BHF Glasgow Cardiovascular Research Centre, University of Glasgow, 126 University Place, Glasgow, G12 8TA, UK.
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18
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Billaud M, Chiu YH, Lohman AW, Parpaite T, Butcher JT, Mutchler SM, DeLalio LJ, Artamonov MV, Sandilos JK, Best AK, Somlyo AV, Thompson RJ, Le TH, Ravichandran KS, Bayliss DA, Isakson BE. A molecular signature in the pannexin1 intracellular loop confers channel activation by the α1 adrenoreceptor in smooth muscle cells. Sci Signal 2015; 8:ra17. [PMID: 25690012 DOI: 10.1126/scisignal.2005824] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Both purinergic signaling through nucleotides such as ATP (adenosine 5'-triphosphate) and noradrenergic signaling through molecules such as norepinephrine regulate vascular tone and blood pressure. Pannexin1 (Panx1), which forms large-pore, ATP-releasing channels, is present in vascular smooth muscle cells in peripheral blood vessels and participates in noradrenergic responses. Using pharmacological approaches and mice conditionally lacking Panx1 in smooth muscle cells, we found that Panx1 contributed to vasoconstriction mediated by the α1 adrenoreceptor (α1AR), whereas vasoconstriction in response to serotonin or endothelin-1 was independent of Panx1. Analysis of the Panx1-deficient mice showed that Panx1 contributed to blood pressure regulation especially during the night cycle when sympathetic nervous activity is highest. Using mimetic peptides and site-directed mutagenesis, we identified a specific amino acid sequence in the Panx1 intracellular loop that is essential for activation by α1AR signaling. Collectively, these data describe a specific link between noradrenergic and purinergic signaling in blood pressure homeostasis.
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Affiliation(s)
- Marie Billaud
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA. Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Yu-Hsin Chiu
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Alexander W Lohman
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA. Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Thibaud Parpaite
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Joshua T Butcher
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Stephanie M Mutchler
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Leon J DeLalio
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA. Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Mykhaylo V Artamonov
- Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Joanna K Sandilos
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Angela K Best
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Avril V Somlyo
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA. Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Roger J Thompson
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | - Thu H Le
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Kodi S Ravichandran
- Center for Cell Clearance, University of Virginia, Charlottesville, VA 22908, USA. Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA 22908, USA. Beirne B. Carter Center for Immunology Research, University of Virginia, Charlottesville, VA 22908, USA
| | - Douglas A Bayliss
- Department of Pharmacology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Brant E Isakson
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA. Department of Molecular Physiology and Biophysics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
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19
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Ji Y, Fish PM, Strawn TL, Lohman AW, Wu J, Szalai AJ, Fay WP. C-reactive protein induces expression of tissue factor and plasminogen activator inhibitor-1 and promotes fibrin accumulation in vein grafts. J Thromb Haemost 2014; 12:1667-77. [PMID: 25081365 PMCID: PMC4194135 DOI: 10.1111/jth.12680] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 07/21/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND C-reactive protein (CRP) promotes tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) expression in vitro, and an elevated plasma CRP concentration is associated with an increased risk of vein graft (VG) thrombosis after coronary artery bypass surgery. However, little is known about the effects of CRP on VG TF and PAI-1 expression in vivo, or on VG thrombosis. OBJECTIVES We studied transgenic (Tg) mice expressing human CRP in a VG model to explore in vivo cause-and-effect relationships between CRP and TF, PAI-1, and VG thrombosis. METHODS Vein segments from wild-type (WT) and CRP-Tg donors were transplanted into carotid arteries of WT and CRP-Tg recipients. VGs were analyzed 1-4 weeks later. RESULTS Human CRP accumulated in VGs during the first 4 weeks after surgery, but appeared to originate exclusively from systemic sources, rather than local production. Human CRP significantly increased TF gene expression, protein concentration and activity in VGs. Human CRP also increased PAI-1 concentrations in VGs, although only in vascular endothelial cells. Human CRP stimulated macrophage migration, invasion into VGs, and TF expression. Fibrin deposition was significantly greater in VGs of CRP-Tg mice than in WT controls. CONCLUSIONS CRP accumulates in VGs early after surgery, originating from systemic sources rather than local synthesis. Human CRP promotes TF and PAI-1 expression in VGs, although with different expression patterns. Human CRP stimulates macrophage invasion and fibrin deposition within VGs. These results suggest that CRP induces pathologic changes in VGs that contribute to early VG occlusion.
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Affiliation(s)
- Y Ji
- Department of Medicine and Medical Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO, USA
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20
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Billaud M, Lohman AW, Johnstone SR, Biwer LA, Mutchler S, Isakson BE. Regulation of cellular communication by signaling microdomains in the blood vessel wall. Pharmacol Rev 2014; 66:513-69. [PMID: 24671377 DOI: 10.1124/pr.112.007351] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
It has become increasingly clear that the accumulation of proteins in specific regions of the plasma membrane can facilitate cellular communication. These regions, termed signaling microdomains, are found throughout the blood vessel wall where cellular communication, both within and between cell types, must be tightly regulated to maintain proper vascular function. We will define a cellular signaling microdomain and apply this definition to the plethora of means by which cellular communication has been hypothesized to occur in the blood vessel wall. To that end, we make a case for three broad areas of cellular communication where signaling microdomains could play an important role: 1) paracrine release of free radicals and gaseous molecules such as nitric oxide and reactive oxygen species; 2) role of ion channels including gap junctions and potassium channels, especially those associated with the endothelium-derived hyperpolarization mediated signaling, and lastly, 3) mechanism of exocytosis that has considerable oversight by signaling microdomains, especially those associated with the release of von Willebrand factor. When summed, we believe that it is clear that the organization and regulation of signaling microdomains is an essential component to vessel wall function.
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Affiliation(s)
- Marie Billaud
- Dept. of Molecular Physiology and Biophysics, University of Virginia School of Medicine, PO Box 801394, Charlottesville, VA 22902.
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21
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Lohman AW, Isakson BE. Differentiating connexin hemichannels and pannexin channels in cellular ATP release. FEBS Lett 2014; 588:1379-88. [PMID: 24548565 DOI: 10.1016/j.febslet.2014.02.004] [Citation(s) in RCA: 137] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Revised: 02/06/2014] [Accepted: 02/06/2014] [Indexed: 12/22/2022]
Abstract
Adenosine triphosphate (ATP) plays a fundamental role in cellular communication, with its extracellular accumulation triggering purinergic signaling cascades in a diversity of cell types. While the roles for purinergic signaling in health and disease have been well established, identification and differentiation of the specific mechanisms controlling cellular ATP release is less well understood. Multiple mechanisms have been proposed to regulate ATP release with connexin (Cx) hemichannels and pannexin (Panx) channels receiving major focus. However, segregating the specific roles of Panxs and Cxs in ATP release in a plethora of physiological and pathological contexts has remained enigmatic. This multifaceted problem has arisen from the selectivity of pharmacological inhibitors for Panxs and Cxs, methodological differences in assessing Panx and Cx function and the potential compensation by other isoforms in gene silencing and genetic knockout models. Consequently, there remains a void in the current understanding of specific contributions of Panxs and Cxs in releasing ATP during homeostasis and disease. Differentiating the distinct signaling pathways that regulate these two channels will advance our current knowledge of cellular communication and aid in the development of novel rationally-designed drugs for modulation of Panx and Cx activity, respectively.
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Affiliation(s)
- Alexander W Lohman
- Department of Molecular Physiology and Biophysics, University of Virginia, Charlottesville, VA 22098, United States; Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, VA 22908, United States
| | - Brant E Isakson
- Department of Molecular Physiology and Biophysics, University of Virginia, Charlottesville, VA 22098, United States; Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, VA 22908, United States.
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22
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Penuela S, Lohman AW, Lai W, Gyenis L, Litchfield DW, Isakson BE, Laird DW. Diverse post-translational modifications of the pannexin family of channel-forming proteins. Channels (Austin) 2014; 8:124-30. [PMID: 24418849 DOI: 10.4161/chan.27422] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The pannexin family of channel-forming proteins is composed of 3 distinct but related members called Panx1, Panx2, and Panx3. Pannexins have been implicated in many physiological processes as well as pathological conditions, primarily through their function as ATP release channels. However, it is currently unclear if all pannexins are subject to similar or different post-translational modifications as most studies have focused primarily on Panx1. Using in vitro biochemical assays performed on ectopically expressed pannexins in HEK-293T cells, we confirmed that all 3 pannexins are N-glycosylated to different degrees, but they are not modified by sialylation or O-linked glycosylation in a manner that changes their apparent molecular weight. Using cell-free caspase assays, we also discovered that similar to Panx1, the C-terminus of Panx2 is a substrate for caspase cleavage. Panx3, on the other hand, is not subject to caspase digestion but an in vitro biotin switch assay revealed that it was S-nitrosylated by nitric oxide donors. Taken together, our findings uncover novel and diverse pannexin post-translational modifications suggesting that they may be differentially regulated for distinct or overlapping cellular and physiological functions.
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Affiliation(s)
- Silvia Penuela
- Department of Anatomy and Cell Biology; University of Western Ontario; London, ON Canada
| | - Alexander W Lohman
- Robert M Berne Cardiovascular Research Center; Department of Molecular Physiology and Biological Physics; University of Virginia; Charlottesville, VA USA
| | - Wesley Lai
- Department of Anatomy and Cell Biology; University of Western Ontario; London, ON Canada; Department of Molecular Genetics; University of Toronto; The Hospital for Sick Children; Toronto, ON Canada
| | - Laszlo Gyenis
- Department of Biochemistry; University of Western Ontario; London, ON Canada
| | - David W Litchfield
- Department of Biochemistry; University of Western Ontario; London, ON Canada
| | - Brant E Isakson
- Robert M Berne Cardiovascular Research Center; Department of Molecular Physiology and Biological Physics; University of Virginia; Charlottesville, VA USA
| | - Dale W Laird
- Department of Anatomy and Cell Biology; University of Western Ontario; London, ON Canada
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23
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Straub AC, Lohman AW, Billaud M, Johnstone SR, Dwyer ST, Lee MY, Bortz PS, Best AK, Columbus L, Gaston B, Isakson BE. Endothelial cell expression of haemoglobin α regulates nitric oxide signalling. Nature 2012; 491:473-7. [PMID: 23123858 PMCID: PMC3531883 DOI: 10.1038/nature11626] [Citation(s) in RCA: 233] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 09/27/2012] [Indexed: 01/27/2023]
Affiliation(s)
- Adam C Straub
- Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22908, USA
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24
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Lohman AW, Weaver JL, Billaud M, Sandilos JK, Griffiths R, Straub AC, Penuela S, Leitinger N, Laird DW, Bayliss DA, Isakson BE. S-nitrosylation inhibits pannexin 1 channel function. J Biol Chem 2012; 287:39602-12. [PMID: 23033481 DOI: 10.1074/jbc.m112.397976] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
S-nitrosylation is a post-translational modification on cysteine(s) that can regulate protein function, and pannexin 1 (Panx1) channels are present in the vasculature, a tissue rich in nitric oxide (NO) species. Therefore, we investigated whether Panx1 can be S-nitrosylated and whether this modification can affect channel activity. Using the biotin switch assay, we found that application of the NO donor S-nitrosoglutathione (GSNO) or diethylammonium (Z)-1-1(N,N-diethylamino)diazen-1-ium-1,2-diolate (DEA NONOate) to human embryonic kidney (HEK) 293T cells expressing wild type (WT) Panx1 and mouse aortic endothelial cells induced Panx1 S-nitrosylation. Functionally, GSNO and DEA NONOate attenuated Panx1 currents; consistent with a role for S-nitrosylation, current inhibition was reversed by the reducing agent dithiothreitol and unaffected by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, a blocker of guanylate cyclase activity. In addition, ATP release was significantly inhibited by treatment with both NO donors. To identify which cysteine residue(s) was S-nitrosylated, we made single cysteine-to-alanine substitutions in Panx1 (Panx1(C40A), Panx1(C346A), and Panx1(C426A)). Mutation of these single cysteines did not prevent Panx1 S-nitrosylation; however, mutation of either Cys-40 or Cys-346 prevented Panx1 current inhibition and ATP release by GSNO. This observation suggested that multiple cysteines may be S-nitrosylated to regulate Panx1 channel function. Indeed, we found that mutation of both Cys-40 and Cys-346 (Panx1(C40A/C346A)) prevented Panx1 S-nitrosylation by GSNO as well as the GSNO-mediated inhibition of Panx1 current and ATP release. Taken together, these results indicate that S-nitrosylation of Panx1 at Cys-40 and Cys-346 inhibits Panx1 channel currents and ATP release.
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Affiliation(s)
- Alexander W Lohman
- Robert M. Berne Cardiovascular Research Center, University of Virginia, Charlottesville, Virginia 22908, USA
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25
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Billaud M, Lohman AW, Straub AC, Parpaite T, Johnstone SR, Isakson BE. Characterization of the thoracodorsal artery: morphology and reactivity. Microcirculation 2012; 19:360-72. [PMID: 22335567 DOI: 10.1111/j.1549-8719.2012.00172.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
OBJECTIVES In this paper, we describe the histological and contractile properties of the thoracodorsal artery (TDA), which indirectly feeds the spinotrapezius muscle. METHODS We used immunolabelling techniques to histologically characterize the TDA while the contractile properties were assessed using pressure arteriography. RESULTS Our results demonstrate that the TDA is composed of approximately one to two layers of smooth muscle cells, is highly innervated with adrenergic nerves, and develops spontaneous tone at intraluminal pressures above 80 mmHg. The reactivity of the TDA in response to various contractile agonists such as phenylephrine, noradrenaline, angiotensin II, serotonin, endothelin 1, and ATP, as well as vasodilators, shows that the TDA exhibits a remarkably comparable reactivity to what has been observed in mesenteric arteries. We further studied the different components of the TDA response to acetylcholine, and found that the TDA was sensitive to TRAM 34, a blocker of the intermediate conductance potassium channel, which is highly suggestive of an endothelium-dependent hyperpolarization. CONCLUSIONS We conclude that the TDA exhibits comparable characteristics to other current vascular models, with the additional advantage of being easily manipulated for molecular and ex vivo vasoreactivity studies.
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Affiliation(s)
- Marie Billaud
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, Virginia 22908, USA
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26
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Johnstone SR, Billaud M, Lohman AW, Taddeo EP, Isakson BE. Posttranslational modifications in connexins and pannexins. J Membr Biol 2012; 245:319-32. [PMID: 22739962 DOI: 10.1007/s00232-012-9453-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Accepted: 06/08/2012] [Indexed: 01/17/2023]
Abstract
Posttranslational modification is a common cellular process that is used by cells to ensure a particular protein function. This can happen in a variety of ways, e.g., from the addition of phosphates or sugar residues to a particular amino acid, ensuring proper protein life cycle and function. In this review, we assess the evidence for ubiquitination, glycosylation, phosphorylation, S-nitrosylation as well as other modifications in connexins and pannexin proteins. Based on the literature, we find that posttranslational modifications are an important component of connexin and pannexin regulation.
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Affiliation(s)
- Scott R Johnstone
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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27
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Lohman AW, Billaud M, Straub AC, Johnstone SR, Best AK, Lee M, Barr K, Penuela S, Laird DW, Isakson BE. Expression of pannexin isoforms in the systemic murine arterial network. J Vasc Res 2012; 49:405-16. [PMID: 22739252 DOI: 10.1159/000338758] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Accepted: 04/04/2012] [Indexed: 12/20/2022] Open
Abstract
AIMS Pannexins (Panx) form ATP release channels and it has been proposed that they play an important role in the regulation of vascular tone. However, distribution of Panx across the arterial vasculature is not documented. METHODS We tested antibodies against Panx1, Panx2 and Panx3 on human embryonic kidney cells (which do not endogenously express Panx proteins) transfected with plasmids encoding each Panx isoform and Panx1(-/-) mice. Each of the Panx antibodies was found to be specific and was tested on isolated arteries using immunocytochemistry. RESULTS We demonstrated that Panx1 is the primary isoform detected in the arterial network. In large arteries, Panx1 is primarily in endothelial cells, whereas in small arteries and arterioles it localizes primarily to the smooth muscle cells. Panx1 was the predominant isoform expressed in coronary arteries, except in arteries less than 100 µm where Panx3 became detectable. Only Panx3 was expressed in the juxtaglomerular apparatus and cortical arterioles. The pulmonary artery and alveoli had expression of all 3 Panx isoforms. No Panx isoforms were detected at the myoendothelial junctions. CONCLUSION We conclude that the specific localized expression of Panx channels throughout the vasculature points towards an important role for these channels in regulating the release of ATP throughout the arterial network.
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Affiliation(s)
- Alexander W Lohman
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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28
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Abstract
The nucleotide adenosine 5'-triphosphate (ATP) has classically been considered the cell's primary energy currency. Importantly, a novel role for ATP as an extracellular autocrine and/or paracrine signalling molecule has evolved over the past century and extensive work has been conducted to characterize the ATP-sensitive purinergic receptors expressed on almost all cell types in the body. Extracellular ATP elicits potent effects on vascular cells to regulate blood vessel tone but can also be involved in vascular pathologies such as atherosclerosis. While the effects of purinergic signalling in the vasculature have been well documented, the mechanism(s) mediating the regulated release of ATP from cells in the blood vessel wall and circulation are now a key target of investigation. The aim of this review is to examine the current proposed mechanisms of ATP release from vascular cells, with a special emphasis on the transporters and channels involved in ATP release from vascular smooth muscle cells, endothelial cells, circulating red blood cells, and perivascular sympathetic nerves, including vesicular exocytosis, plasma membrane F(1)/F(0)-ATP synthase, ATP-binding cassette (ABC) transporters, connexin hemichannels, and pannexin channels.
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Affiliation(s)
- Alexander W Lohman
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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Lohman AW, Weaver JL, Billaud M, Bayliss DA, Isakson BE. Complex interplay between Pannexin 1 cysteine residues and channel regulation. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1131.7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Alexander W Lohman
- Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | | | - Marie Billaud
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | | | - Brant E Isakson
- Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
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Billaud M, Lohman AW, Chiu YH, Sandilos JK, Bayliss DA, Isakson BE. Exclusive interaction between α1D‐adrenergic receptor and pannexin 1 can mediate vasoconstriction. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.1058.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Marie Billaud
- Robert M Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | - Alexander W Lohman
- Robert M Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
- Department of Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA
| | - Yu-Hsin Chiu
- Department of PharmacologyUniversity of VirginiaCharlottesvilleVA
| | | | - Doug A Bayliss
- Department of PharmacologyUniversity of VirginiaCharlottesvilleVA
| | - Brant E Isakson
- Robert M Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
- Department of Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA
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Lohman AW, Billaud M, Straub AC, Best AK, Lee M, Barr K, Penuela S, Laird D, Isakson BE. Expression of pannexin isoforms in the murine arterial network. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.676.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Alexander W Lohman
- Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | - Marie Billaud
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | - Adam C Straub
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | - Angela K Best
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | - Monica Lee
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
| | - Kevin Barr
- Department of Anatomy and Cell BiologyUniversity of Western OntarioLondonONCanada
| | - Silvia Penuela
- Department of Anatomy and Cell BiologyUniversity of Western OntarioLondonONCanada
| | - Dale Laird
- Department of Anatomy and Cell BiologyUniversity of Western OntarioLondonONCanada
| | - Brant E Isakson
- Molecular Physiology and Biological PhysicsUniversity of VirginiaCharlottesvilleVA
- Robert M. Berne Cardiovascular Research CenterUniversity of VirginiaCharlottesvilleVA
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Ji Y, Strawn TL, Grunz EA, Stevenson MJ, Lohman AW, Lawrence DA, Fay WP. Multifaceted role of plasminogen activator inhibitor-1 in regulating early remodeling of vein bypass grafts. Arterioscler Thromb Vasc Biol 2011; 31:1781-7. [PMID: 21571686 DOI: 10.1161/atvbaha.111.228767] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE The role of plasminogen activator inhibitor-1 (PAI-1) in vein graft (VG) remodeling is undefined. We examined the effect of PAI-1 on VG intimal hyperplasia and tested the hypothesis that PAI-1 regulates VG thrombin activity. METHODS AND RESULTS VGs from wild-type (WT), Pai1(-/-), and PAI-1-transgenic mice were implanted into WT, Pai1(-/-), or PAI-1-transgenic arteries. VG remodeling was assessed 4 weeks later. Intimal hyperplasia was significantly greater in PAI-1-deficient mice than in WT mice. The proliferative effect of PAI-1 deficiency was retained in vitronectin-deficient mice, suggesting that PAI-1's antiproteolytic function plays a key role in regulating intimal hyperplasia. Thrombin-induced proliferation of PAI-1-deficient venous smooth muscle cells (SMC) was significantly greater than that of WT SMC, and thrombin activity was significantly higher in PAI-1-deficient VGs than in WT VGs. Increased PAI-1 expression, which has been associated with obstructive VG disease, did not increase intimal hyperplasia. CONCLUSIONS Decreased PAI-1 expression (1) promotes intimal hyperplasia by pathways that do not require vitronectin and (2) increases thrombin activity in VG. PAI-1 overexpression, although it promotes SMC migration in vitro, did not increase intimal hyperplasia. These results challenge the concept that PAI-1 drives nonthrombotic obstructive disease in VG and suggest that PAI-1's antiproteolytic function, including its antithrombin activity, inhibits intimal hyperplasia.
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Affiliation(s)
- Yan Ji
- Department of Internal Medicine and Medical Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, MO, USA
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Billaud M, Lohman AW, Straub AC, Looft-Wilson R, Johnstone SR, Araj CA, Best AK, Chekeni FB, Ravichandran KS, Penuela S, Laird DW, Isakson BE. Pannexin1 regulates α1-adrenergic receptor- mediated vasoconstriction. Circ Res 2011; 109:80-5. [PMID: 21546608 DOI: 10.1161/circresaha.110.237594] [Citation(s) in RCA: 146] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
RATIONALE The coordination of vascular smooth muscle cell constriction plays an important role in vascular function, such as regulation of blood pressure; however, the mechanism responsible for vascular smooth muscle cell communication is not clear in the resistance vasculature. Pannexins (Panx) are purine-releasing channels permeable to the vasoconstrictor ATP and thus may play a role in the coordination of vascular smooth muscle cell constriction. OBJECTIVE We investigated the role of pannexins in phenylephrine- and KCl-mediated constriction of resistance arteries. METHODS AND RESULTS Western blot, immunohistochemistry, and immunogold labeling coupled to scanning and transmission electron microscopy revealed the presence of Panx1 but not Panx2 or Panx3 in thoracodorsal resistance arteries. Functionally, the contractile response of pressurized thoracodorsal resistance arteries to phenylephrine was decreased significantly by multiple Panx inhibitors (mefloquine, probenecid, and (10)Panx1), ectonucleotidase (apyrase), and purinergic receptor inhibitors (suramin and reactive blue-2). Electroporation of thoracodorsal resistance arteries with either Panx1-green fluorescent protein or Panx1 small interfering RNA showed enhanced and decreased constriction, respectively, in response to phenylephrine. Lastly, the Panx inhibitors did not alter constriction in response to KCl. This result is consistent with coimmunoprecipitation experiments from thoracodorsal resistance arteries, which suggested an association between Panx1 and α1D-adrenergic receptor. CONCLUSIONS Our data demonstrate for the first time a key role for Panx1 in resistance arteries by contributing to the coordination of vascular smooth muscle cell constriction and possibly to the regulation of blood pressure.
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Affiliation(s)
- Marie Billaud
- Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
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