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Patil RS, Kovacs-Kasa A, Gorshkov BA, Fulton DJR, Su Y, Batori RK, Verin AD. Serine/Threonine Protein Phosphatases 1 and 2A in Lung Endothelial Barrier Regulation. Biomedicines 2023; 11:1638. [PMID: 37371733 PMCID: PMC10296329 DOI: 10.3390/biomedicines11061638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 05/28/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
Vascular barrier dysfunction is characterized by increased permeability and inflammation of endothelial cells (ECs), which are prominent features of acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and sepsis, and a major complication of the SARS-CoV-2 infection and COVID-19. Functional impairment of the EC barrier and accompanying inflammation arises due to microbial toxins and from white blood cells of the lung as part of a defensive action against pathogens, ischemia-reperfusion or blood product transfusions, and aspiration syndromes-based injury. A loss of barrier function results in the excessive movement of fluid and macromolecules from the vasculature into the interstitium and alveolae resulting in pulmonary edema and collapse of the architecture and function of the lungs, and eventually culminates in respiratory failure. Therefore, EC barrier integrity, which is heavily dependent on cytoskeletal elements (mainly actin filaments, microtubules (MTs), cell-matrix focal adhesions, and intercellular junctions) to maintain cellular contacts, is a critical requirement for the preservation of lung function. EC cytoskeletal remodeling is regulated, at least in part, by Ser/Thr phosphorylation/dephosphorylation of key cytoskeletal proteins. While a large body of literature describes the role of phosphorylation of cytoskeletal proteins on Ser/Thr residues in the context of EC barrier regulation, the role of Ser/Thr dephosphorylation catalyzed by Ser/Thr protein phosphatases (PPases) in EC barrier regulation is less documented. Ser/Thr PPases have been proposed to act as a counter-regulatory mechanism that preserves the EC barrier and opposes EC contraction. Despite the importance of PPases, our knowledge of the catalytic and regulatory subunits involved, as well as their cellular targets, is limited and under-appreciated. Therefore, the goal of this review is to discuss the role of Ser/Thr PPases in the regulation of lung EC cytoskeleton and permeability with special emphasis on the role of protein phosphatase 1 (PP1) and protein phosphatase 2A (PP2A) as major mammalian Ser/Thr PPases. Importantly, we integrate the role of PPases with the structural dynamics of the cytoskeleton and signaling cascades that regulate endothelial cell permeability and inflammation.
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Affiliation(s)
- Rahul S. Patil
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Anita Kovacs-Kasa
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Boris A. Gorshkov
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - David J. R. Fulton
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
- Department of Pharmacology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Yunchao Su
- Department of Pharmacology, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Robert K. Batori
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
| | - Alexander D. Verin
- Vascular Biology Center, Medical College of Georgia, Augusta University, Augusta, GA 30912, USA
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Neumann J, Hofmann B, Kirchhefer U, Dhein S, Gergs U. Function and Role of Histamine H 1 Receptor in the Mammalian Heart. Pharmaceuticals (Basel) 2023; 16:ph16050734. [PMID: 37242517 DOI: 10.3390/ph16050734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
Histamine can change the force of cardiac contraction and alter the beating rate in mammals, including humans. However, striking species and regional differences have been observed. Depending on the species and the cardiac region (atrium versus ventricle) studied, the contractile, chronotropic, dromotropic, and bathmotropic effects of histamine vary. Histamine is present and is produced in the mammalian heart. Thus, histamine may exert autocrine or paracrine effects in the mammalian heart. Histamine uses at least four heptahelical receptors: H1, H2, H3 and H4. Depending on the species and region studied, cardiomyocytes express only histamine H1 or only histamine H2 receptors or both. These receptors are not necessarily functional concerning contractility. We have considerable knowledge of the cardiac expression and function of histamine H2 receptors. In contrast, we have a poor understanding of the cardiac role of the histamine H1 receptor. Therefore, we address the structure, signal transduction, and expressional regulation of the histamine H1 receptor with an eye on its cardiac role. We point out signal transduction and the role of the histamine H1 receptor in various animal species. This review aims to identify gaps in our knowledge of cardiac histamine H1 receptors. We highlight where the published research shows disagreements and requires a new approach. Moreover, we show that diseases alter the expression and functional effects of histamine H1 receptors in the heart. We found that antidepressive drugs and neuroleptic drugs might act as antagonists of cardiac histamine H1 receptors, and believe that histamine H1 receptors in the heart might be attractive targets for drug therapy. The authors believe that a better understanding of the role of histamine H1 receptors in the human heart might be clinically relevant for improving drug therapy.
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Affiliation(s)
- Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Magdeburger Straße 4, Martin-Luther-Universität Halle-Wittenberg, 06097 Halle, Germany
| | - Britt Hofmann
- Herzchirurgie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube Straße 40, 06097 Halle, Germany
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Domagkstraße 12, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | - Stefan Dhein
- Rudolf-Boehm Institut für Pharmakologie und Toxikologie, Härtelstraße 16-18, Universität Leipzig, 04107 Leipzig, Germany
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Magdeburger Straße 4, Martin-Luther-Universität Halle-Wittenberg, 06097 Halle, Germany
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3
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D’Aniello E, Paganos P, Anishchenko E, D’Aniello S, Arnone MI. Comparative Neurobiology of Biogenic Amines in Animal Models in Deuterostomes. Front Ecol Evol 2020. [DOI: 10.3389/fevo.2020.587036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Annunziata MC, Parisi M, Esposito G, Fabbrocini G, Ammendola R, Cattaneo F. Phosphorylation Sites in Protein Kinases and Phosphatases Regulated by Formyl Peptide Receptor 2 Signaling. Int J Mol Sci 2020; 21:ijms21113818. [PMID: 32471307 PMCID: PMC7312799 DOI: 10.3390/ijms21113818] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 05/22/2020] [Accepted: 05/25/2020] [Indexed: 12/19/2022] Open
Abstract
FPR1, FPR2, and FPR3 are members of Formyl Peptides Receptors (FPRs) family belonging to the GPCR superfamily. FPR2 is a low affinity receptor for formyl peptides and it is considered the most promiscuous member of this family. Intracellular signaling cascades triggered by FPRs include the activation of different protein kinases and phosphatase, as well as tyrosine kinase receptors transactivation. Protein kinases and phosphatases act coordinately and any impairment of their activation or regulation represents one of the most common causes of several human diseases. Several phospho-sites has been identified in protein kinases and phosphatases, whose role may be to expand the repertoire of molecular mechanisms of regulation or may be necessary for fine-tuning of switch properties. We previously performed a phospho-proteomic analysis in FPR2-stimulated cells that revealed, among other things, not yet identified phospho-sites on six protein kinases and one protein phosphatase. Herein, we discuss on the selective phosphorylation of Serine/Threonine-protein kinase N2, Serine/Threonine-protein kinase PRP4 homolog, Serine/Threonine-protein kinase MARK2, Serine/Threonine-protein kinase PAK4, Serine/Threonine-protein kinase 10, Dual specificity mitogen-activated protein kinase kinase 2, and Protein phosphatase 1 regulatory subunit 14A, triggered by FPR2 stimulation. We also describe the putative FPR2-dependent signaling cascades upstream to these specific phospho-sites.
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Affiliation(s)
- Maria Carmela Annunziata
- Department of Clinical Medicine and Surgery, School of Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy; (M.C.A.); (M.P.); (G.F.)
| | - Melania Parisi
- Department of Clinical Medicine and Surgery, School of Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy; (M.C.A.); (M.P.); (G.F.)
| | - Gabriella Esposito
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy; (G.E.); (R.A.)
| | - Gabriella Fabbrocini
- Department of Clinical Medicine and Surgery, School of Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy; (M.C.A.); (M.P.); (G.F.)
| | - Rosario Ammendola
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy; (G.E.); (R.A.)
| | - Fabio Cattaneo
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy; (G.E.); (R.A.)
- Correspondence: ; Fax: +39-081-7464-359
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Tzeng HP, Yang TH, Wu CT, Chiu HC, Liu SH, Lan KC. Benzo[a]pyrene alters vascular function in rat aortas ex vivo and in vivo. Vascul Pharmacol 2019; 121:106578. [PMID: 31279923 DOI: 10.1016/j.vph.2019.106578] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 05/14/2019] [Accepted: 07/04/2019] [Indexed: 01/01/2023]
Abstract
Benzo[a]pyrene (BaP) is a polycyclic aromatic hydrocarbon found in tobacco smoke and air pollution products. BaP exposure has been recently suggested to be a risk factor for hypertension in coke oven workers. The mechanisms of BaP on vascular smooth muscle function remain unclear. Here, we examined the influence and possible mechanism of BaP on vasoconstriction in rat thoracic aortas ex vivo and in vivo. In vivo exposure of rats to BaP (20 mg/kg) for 8 weeks caused a significant enhancement in the systolic blood pressure and enhanced aortic hyperreactivity to α1-adrenoceptor selective agonist phenylephrine in aortas. BaP (1 and 10 μM) treatment for 18 h induced an enhancement of phenylephrine-induced vasoconstriction in the organ cultures of aortas. Aryl hydrocarbon receptor antagonist α-naphthoflavone, protein kinase C (PKC) inhibitor chelerythrine, mitogen-activated protein kinases (MAPK) inhibitor PD98059, myosin light chain kinase (MLCK) inhibitor ML-9, and Rho-kinase inhibitor Y-27632 significantly suppressed BaP-enhanced vasoconstriction. BaP time-dependently triggered reactive oxygen species (ROS) production in primary vascular smooth muscle cells. Both antioxidant N-acetylcysteine and NAD(P)H oxidase inhibitor diphenyleneiodonium significantly inhibited BaP-triggered ROS production and vasoconstriction. These results suggest that BaP enhances aortic vasoconstriction via the activation of ROS and muscular signaling molecules PKC, MAPK, MLCK, and Rho-kinase.
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Affiliation(s)
- Huei-Ping Tzeng
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ting-Hua Yang
- Department of Otolaryngology, National Taiwan University College of Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Cheng-Tien Wu
- Department of Surgery, Shuang Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
| | - Hsien-Chun Chiu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shing-Hwa Liu
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Pediatrics, College of Medicine, National Taiwan University, Taipei, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan.
| | - Kuo-Cheng Lan
- Department of Emergency Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
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Human phagocytic cell response to histamine derived from potential probiotic strains of Lactobacillus reuteri. Immunobiology 2018; 223:618-626. [PMID: 30037587 DOI: 10.1016/j.imbio.2018.07.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 05/18/2018] [Accepted: 07/05/2018] [Indexed: 11/22/2022]
Abstract
Histamine derived from lactobacilli isolates is considered to be a potential immunomodulator able to interact with the host immune system. We tested the effect of pure histamine (0.413 mM) together with the effect of cell-culture supernatants (CCS) containing different concentration of histamine produced by two of Lactobacillus reuteri isolates on the activities of antioxidant enzyme, as well as on the phagocytic activity of human leucocytes (HL). Phagocytic activity represents the non-specific immune response of HL homogenate, in vitro. Analysed histamine-producers were represented by a goatling isolate named L. reuteri KO5 and a lamb isolate named L. reuteri E and histamine production was determined using HPLC method connected with UV detection. Concretely, the samples contained the mixture of isolated HL and the addition of lactobacilli CCS at three different final concentrations of histamine ∼ 0.1, 1.8 and 5.4 mM. It was found that pure histamine (0.413 mM) did not significantly influence the oxidant-antioxidant balance in HL demonstrated by unchanged degree of HL lipid peroxidation. However, at the same time, the final activity of catalase and superoxide dismutase were significantly changed (p ≤ 0.001). Moreover, the phagocytic index (p ≤ 0.01), lysozyme (p ≤ 0.05) and peroxidase activity (p ≤ 0.001), and production of IL-1β significantly decreased. CCS containing different concentration of produced histamine were also able to modulate the host non-specific immune response together with the enzymatic activity of SOD and catalase too. However, our findings indicated that the impact of lactobacilli histamine is strictly strain-dependent and concentration dependent. Moreover, it seems that histamine is not the only one lactobacilli metabolite, which may play an important role in overall immunomodulatory and antioxidant potential of tested lactobacilli.
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7
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Eto M, Kitazawa T. Diversity and plasticity in signaling pathways that regulate smooth muscle responsiveness: Paradigms and paradoxes for the myosin phosphatase, the master regulator of smooth muscle contraction. J Smooth Muscle Res 2018; 53:1-19. [PMID: 28260704 PMCID: PMC5364378 DOI: 10.1540/jsmr.53.1] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
A hallmark of smooth muscle cells is their ability to adapt their functions to meet temporal and chronic fluctuations in their demands. These functions include force development and growth. Understanding the mechanisms underlying the functional plasticity of smooth muscles, the major constituent of organ walls, is fundamental to elucidating pathophysiological rationales of failures of organ functions. Also, the knowledge is expected to facilitate devising innovative strategies that more precisely monitor and normalize organ functions by targeting individual smooth muscles. Evidence has established a current paradigm that the myosin light chain phosphatase (MLCP) is a master regulator of smooth muscle responsiveness to stimuli. Cellular MLCP activity is negatively and positively regulated in response to G-protein activation and cAMP/cGMP production, respectively, through the MYPT1 regulatory subunit and an endogenous inhibitor protein named CPI-17. In this article we review the outcomes from two decade of research on the CPI-17 signaling and discuss emerging paradoxes in the view of signaling pathways regulating smooth muscle functions through MLCP.
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Affiliation(s)
- Masumi Eto
- Department of Molecular Physiology and Biophysics, Sidney Kimmel Medical College at Thomas Jefferson University and Sidney Kimmel Cancer Center, 1020 Locust Street, Philadelphia, PA19107, USA
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8
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Lin S, Brozovich FV. MYPT1 isoforms expressed in HEK293T cells are differentially phosphorylated after GTPγS treatment. J Smooth Muscle Res 2017; 52:66-77. [PMID: 27725371 PMCID: PMC5321854 DOI: 10.1540/jsmr.52.66] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Agonist stimulation of smooth muscle is known to activate RhoA/Rho kinase signaling, and
Rho kinase phosphorylates the myosin targeting subunit (MYPT1) of myosin light chain (MLC)
phosphatase at Thr696 and Thr853, which inhibits the activity of MLC phosphatase to
produce a Ca2+ independent increase in MLC phosphorylation and force (Ca2+ sensitization).
Alternative mRNA splicing produces four MYPT1 isoforms, which differ by the presence or
absence of a central insert (CI) and leucine zipper (LZ). This study was designed to
determine if Rho kinase differentially phosphorylates MYPT1 isoforms. In HEK293T cells
expressing each of the four MYPT1 isoforms, we could not detect a change in Thr853 MYPT1
phosphorylation following GTPγS treatment. However, there is differential phosphorylation
of MYPT1 isoforms at Thr696; GTPγS treatment increases MYPT1 phosphorylation for the
CI+LZ- and CI-LZ- MYPT1 isoforms, but not the CI+LZ+ or CI-LZ+ MYPT1 isoforms. These data
could suggest that in smooth muscle Rho kinase differentially phosphorylates MYPT1
isoforms.
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Affiliation(s)
- Simon Lin
- Mayo Medical School, Department of Cardiovascular Disease, Rochester, MN 55905, USA
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9
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Filter JJ, Williams BC, Eto M, Shalloway D, Goldberg ML. Unfair competition governs the interaction of pCPI-17 with myosin phosphatase (PP1-MYPT1). eLife 2017; 6. [PMID: 28387646 PMCID: PMC5441869 DOI: 10.7554/elife.24665] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 03/31/2017] [Indexed: 11/30/2022] Open
Abstract
The small phosphoprotein pCPI-17 inhibits myosin light-chain phosphatase (MLCP). Current models postulate that during muscle relaxation, phosphatases other than MLCP dephosphorylate and inactivate pCPI-17 to restore MLCP activity. We show here that such hypotheses are insufficient to account for the observed rapidity of pCPI-17 inactivation in mammalian smooth muscles. Instead, MLCP itself is the critical enzyme for pCPI-17 dephosphorylation. We call the mutual sequestration mechanism through which pCPI-17 and MLCP interact inhibition by unfair competition: MLCP protects pCPI-17 from other phosphatases, while pCPI-17 blocks other substrates from MLCP’s active site. MLCP dephosphorylates pCPI-17 at a slow rate that is, nonetheless, both sufficient and necessary to explain the speed of pCPI-17 dephosphorylation and the consequent MLCP activation during muscle relaxation. DOI:http://dx.doi.org/10.7554/eLife.24665.001
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Affiliation(s)
- Joshua J Filter
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Byron C Williams
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Masumi Eto
- Department of Molecular Physiology and Biophysics, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, United States
| | - David Shalloway
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Michael L Goldberg
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
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Haick JM, Brueggemann LI, Cribbs LL, Denning MF, Schwartz J, Byron KL. PKC-dependent regulation of Kv7.5 channels by the bronchoconstrictor histamine in human airway smooth muscle cells. Am J Physiol Lung Cell Mol Physiol 2017; 312:L822-L834. [PMID: 28283479 DOI: 10.1152/ajplung.00567.2016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/23/2017] [Accepted: 03/07/2017] [Indexed: 12/13/2022] Open
Abstract
Kv7 potassium channels have recently been found to be expressed and functionally important for relaxation of airway smooth muscle. Previous research suggests that native Kv7 currents are inhibited following treatment of freshly isolated airway smooth muscle cells with bronchoconstrictor agonists, and in intact airways inhibition of Kv7 channels is sufficient to induce bronchiolar constriction. However, the mechanism by which Kv7 currents are inhibited by bronchoconstrictor agonists has yet to be elucidated. In the present study, native Kv7 currents in cultured human trachealis smooth muscle cells (HTSMCs) were observed to be inhibited upon treatment with histamine; inhibition of Kv7 currents was associated with membrane depolarization and an increase in cytosolic Ca2+ ([Ca2+]cyt). The latter response was inhibited by verapamil, a blocker of L-type voltage-sensitive Ca2+ channels (VSCCs). Protein kinase C (PKC) has been implicated as a mediator of bronchoconstrictor actions, although the targets of PKC are not clearly established. We found that histamine treatment significantly and dose-dependently suppressed currents through overexpressed wild-type human Kv7.5 (hKv7.5) channels in cultured HTSMCs, and this effect was inhibited by the PKC inhibitor Ro-31-8220 (3 µM). The PKC-dependent suppression of hKv7.5 currents corresponded with a PKC-dependent increase in hKv7.5 channel phosphorylation. Knocking down or inhibiting PKCα, or mutating hKv7.5 serine 441 to alanine, abolished the inhibitory effects of histamine on hKv7.5 currents. These findings provide the first evidence linking PKC activation to suppression of Kv7 currents, membrane depolarization, and Ca2+ influx via L-type VSCCs as a mechanism for histamine-induced bronchoconstriction.
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Affiliation(s)
- Jennifer M Haick
- Department of Molecular Pharmacology and Therapeutics, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Lioubov I Brueggemann
- Department of Molecular Pharmacology and Therapeutics, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Leanne L Cribbs
- Department of Cell & Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Mitchell F Denning
- Department of Pathology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois; and
| | - Jeffrey Schwartz
- Department of Thoracic and Cardiovascular Surgery, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois
| | - Kenneth L Byron
- Department of Molecular Pharmacology and Therapeutics, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois;
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Ets HK, Seow CY, Moreland RS. Sustained Contraction in Vascular Smooth Muscle by Activation of L-type Ca 2+ Channels Does Not Involve Ca 2+ Sensitization or Caldesmon. Front Pharmacol 2017; 7:516. [PMID: 28082901 PMCID: PMC5183594 DOI: 10.3389/fphar.2016.00516] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 12/12/2016] [Indexed: 11/13/2022] Open
Abstract
Vascular smooth muscle (VSM) is unique in its ability to maintain an intrinsic level of contractile force, known as tone. Vascular tone is believed to arise from the constitutive activity of membrane-bound L-type Ca2+ channels (LTCC). This study used a pharmacological agonist of LTCC, Bay K8644, to elicit a sustained, sub-maximal contraction in VSM that mimics tone. Downstream signaling was investigated in order to determine what molecules are responsible for tone. Medial strips of swine carotid artery were stimulated with 100 nM Bay K8644 to induce a sustained level of force. Force and phosphorylation levels of myosin light chain (MLC), MAP kinase, MYPT1, CPI-17, and caldesmon were measured during Bay K8644 stimulation in the presence and absence of nifedipine, ML-7, U0126, bisindolylmaleimide (Bis), and H-1152. Nifedipine and ML-7 inhibited force and MLC phosphorylation in response to Bay K8644. Inhibition of Rho kinase (H-1152) but not PKC (Bis) inhibited Bay K8644 induced force. U0126 significantly increased Bay K8644-dependent force with no effect on MLC phosphorylation. Neither CPI-17 nor caldesmon phosphorylation were increased during the maintenance of sustained force. Our results suggest that force due to the influx of calcium through LTCCs is partially MLC phosphorylation-dependent but does not involve PKC or caldesmon. Interestingly, inhibition of MLC kinase (MLCK) and PKC significantly increased MAP kinase phosphorylation suggesting that MLCK and PKC may directly or indirectly inhibit MAP kinase activity during prolonged contractions induced by Bay K8544.
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Affiliation(s)
- Hillevi K Ets
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia PA, USA
| | - Chun Y Seow
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver BC, Canada
| | - Robert S Moreland
- Department of Pharmacology and Physiology, Drexel University College of Medicine, PhiladelphiaPA, USA; Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, PhiladelphiaPA, USA
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12
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Jernigan NL, Resta TC, Gonzalez Bosc LV. Altered Redox Balance in the Development of Chronic Hypoxia-induced Pulmonary Hypertension. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 967:83-103. [PMID: 29047083 DOI: 10.1007/978-3-319-63245-2_7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Normally, the pulmonary circulation is maintained in a low-pressure, low-resistance state with little resting tone. Pulmonary arteries are thin-walled and rely heavily on pulmonary arterial distension and recruitment for reducing pulmonary vascular resistance when cardiac output is elevated. Under pathophysiological conditions, however, active vasoconstriction and vascular remodeling lead to enhanced pulmonary vascular resistance and subsequent pulmonary hypertension (PH). Chronic hypoxia is a critical pathological factor associated with the development of PH resulting from airway obstruction (COPD, sleep apnea), diffusion impairment (interstitial lung disease), developmental lung abnormalities, or high altitude exposure (World Health Organization [WHO]; Group III). The rise in pulmonary vascular resistance increases right heart afterload causing right ventricular hypertrophy that can ultimately lead to right heart failure in patients with chronic lung disease. PH is typically characterized by diminished paracrine release of vasodilators, antimitogenic factors, and antithrombotic factors (e.g., nitric oxide and protacyclin) and enhanced production of vasoconstrictors and mitogenic factors (e.g., reactive oxygen species and endothelin-1) from the endothelium and lung parenchyma. In addition, phenotypic changes to pulmonary arterial smooth muscle cells (PASMC), including alterations in Ca2+ homeostasis, Ca2+ sensitivity, and activation of transcription factors are thought to play prominent roles in the development of both vasoconstrictor and arterial remodeling components of hypoxia-associated PH. These changes in PASMC function are briefly reviewed in Sect. 1 and the influence of altered reactive oxygen species homeostasis on PASMC function discussed in Sects. 2-4.
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Affiliation(s)
- Nikki L Jernigan
- Department Cell Biology and Physiology, Vascular Physiology Group, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Thomas C Resta
- Department Cell Biology and Physiology, Vascular Physiology Group, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, NM, 87131, USA
| | - Laura V Gonzalez Bosc
- Department Cell Biology and Physiology, Vascular Physiology Group, University of New Mexico Health Sciences Center, University of New Mexico, Albuquerque, NM, 87131, USA.
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13
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Manzetti S, Andersen O. Biochemical and physiological effects from exhaust emissions. A review of the relevant literature. ACTA ACUST UNITED AC 2016; 23:285-293. [PMID: 27793419 DOI: 10.1016/j.pathophys.2016.10.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 10/20/2016] [Indexed: 01/05/2023]
Abstract
Exhaust emissions are to date ranked among the most frequent causes of premature deaths worldwide. The combustion of fuels such as diesel, gasoline, and bio-blends provokes a series of pathophysiological responses in exposed subjects, which are associated with biochemical and immunological triggering. It is critical to understand these mechanisms, which are directly related to the levels of aerosol, liquid and gaseous components in fuel exhaust (e.g. nanoparticles, particulate matter, volatile compounds), so to cast attention on their toxicity and gradually minimize their use. This review reports findings in the recent literature concerning the biochemical and cellular pathways triggered during intoxication by exhaust emissions, and links these findings to pathophysiological responses such as inflammation and vasoconstriction. This study provides critical in vitro and in vivo data for the reduction of emissions in urban centers, with an emphasis on the prevention of exposure of groups such as children, the elderly, and other affected groups, and shows how the exposure to exhaust emissions induces mechanisms of pathogenesis related to cardiopulmonary pathologies and long-term diseases such as asthma, allergies, and cancer. This review summarizes the cellular and physiological responses of humans to exhaust emissions in a comprehensive fashion, and is important for legislative developments in fuel politics.
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Affiliation(s)
| | - Otto Andersen
- Vestlandsforskning, Fosshaugane Campus, 6851 Sogndal, Norway.
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14
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Kumcu EK, Aydinoglu F, Astarci E, Ogulener N. The effect of sub-chronic systemic ethanol treatment on corpus cavernosal smooth muscle contraction: the contribution of RhoA/Rho-kinase. Naunyn Schmiedebergs Arch Pharmacol 2016; 389:249-58. [DOI: 10.1007/s00210-015-1204-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 12/21/2015] [Indexed: 12/21/2022]
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15
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Hattori Y, Hattori K, Matsuda N. Regulation of the Cardiovascular System by Histamine. Handb Exp Pharmacol 2016; 241:239-258. [PMID: 27838850 DOI: 10.1007/164_2016_15] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Histamine mediates a wide range of cellular responses, including allergic and inflammatory reactions, gastric acid secretion, and neurotransmission in the central nervous system. Histamine also exerts a series of actions upon the cardiovascular system but may not normally play a significant role in regulating cardiovascular function. During tissue injury, inflammation, and allergic responses, mast cells (or non-mast cells) within the tissues can release large amounts of histamine that leads to noticeable cardiovascular effects. Owing to intensive research during several decades, the distribution, function, and pathophysiological role of cardiovascular H1- and H2-receptors has become recognized adequately. Besides the recognized H1- and H2-receptor-mediated cardiovascular responses, novel roles of H3- and H4-receptors in cardiovascular physiology and pathophysiology have been identified over the last decade. In this review, we describe recent advances in our understanding of cardiovascular function and dysfunction mediated by histamine receptors, including H3- and H4-receptors, their potential mechanisms of action, and their pathological significance.
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Affiliation(s)
- Yuichi Hattori
- Department of Molecular and Medical Pharmacology, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.
| | - Kohshi Hattori
- Department of Anesthesiology and Pain Relief Center, The University of Tokyo Hospital, Tokyo, Japan
| | - Naoyuki Matsuda
- Department of Emergency and Critical Care Medicine, Nagoya University Graduate School of Medicine, Nagoya, Japan
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16
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Aydinoglu F, Ergurhan Kiroglu O, Astarci E, Balli E, Ogulener N. Effects of ethanol on RhoA/Rho-kinase-mediated calcium sensitization in mouse lung parenchymal tissue. Eur J Pharmacol 2015; 764:318-327. [PMID: 26169563 DOI: 10.1016/j.ejphar.2015.07.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/29/2015] [Accepted: 07/08/2015] [Indexed: 11/16/2022]
Abstract
Calcium sensitization by the RhoA/Rho-kinase (ROCK) pathway contributes to the contraction in smooth muscle. Contractile stimuli can sensitize myosin to Ca(2+) by activating RhoA/Rho-kinase that inhibits myosin light chain phosphatase activity. The present study was aimed at investigating the possible involvement of RhoA/Rho-kinase pathway in contractile responses to agonist (phenylephrine) and depolarizing (KCl) of mouse lung parenchymal tissues. Also, we investigated the effect of ethanol on RhoA/Rho-kinase pathway. Phenylephrine (10(-8)-10(-4) M) and KCl (10-80 mM) induced sustained contractions in parenchymal strips. Ethanol significantly attenuated the contractions to phenylephrine and KCl. The Rho-kinase inhibitors fasudil (5×10(-5) M) and Y-27632 (5×10(-5) M) inhibited contractions to in both control and ethanol-treated parenchymal strips. In addition, the relaxations induced by fasudil (10(-4) M) and Y-27632 (5×10(-4) M) on parenchymal strips contracted by phenylephrine but not KCl was decreased in ethanol-treatment group. Also, RhoA, ROCK1 and ROCK2 expressions were detected in mouse lung parenchymal tissue. In ethanol-treated group, expression of RhoA and ROCK1 but not ROCK2 decreased compared to control. Furthermore, ethanol causes apoptotic changes in alveolar type I epithelial cells of parenchymal tissue. These results suggest that RhoA/Rho-kinase signaling pathway plays an important role in phenylephrine- and KCl-induced Ca(2)(+) sensitization in mouse lung parenchymal tissue. Also, ethanol may be decrease phenylephrine- and KCl-induced contraction due to lowering the RhoA/Rho-kinase-mediated Ca(2+)-sensitizing by inhibiting RhoA/Rho-kinase pathway in parenchymal tissue. These results may be lead to important insights into the mechanisms of lung diseases due to alcohol consumption.
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Affiliation(s)
- Fatma Aydinoglu
- Department of Pharmacology, Pharmacy Faculty, Cukurova University, Adana, Turkey
| | | | - Erhan Astarci
- Department of Plant and Animal Production, Mudurnu Süreyya Astarci Vocational School, Abant Izzet Baysal University, Bolu, Turkey
| | - Ebru Balli
- Department of Histology and Embryology, Medical Faculty, Mersin University, Mersin, Turkey
| | - Nuran Ogulener
- Department of Pharmacology, Medical Faculty, Cukurova University, Adana, Turkey.
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17
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El-Yazbi AF, Abd-Elrahman KS, Moreno-Dominguez A. PKC-mediated cerebral vasoconstriction: Role of myosin light chain phosphorylation versus actin cytoskeleton reorganization. Biochem Pharmacol 2015; 95:263-78. [DOI: 10.1016/j.bcp.2015.04.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 04/16/2015] [Indexed: 10/23/2022]
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18
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Lim KM, Kwon JH, Kim K, Noh JY, Kang S, Park JM, Lee MY, Bae ON, Chung JH. Emodin inhibits tonic tension through suppressing PKCδ-mediated inhibition of myosin phosphatase in rat isolated thoracic aorta. Br J Pharmacol 2015; 171:4300-10. [PMID: 24909118 DOI: 10.1111/bph.12804] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Revised: 04/29/2014] [Accepted: 05/03/2014] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND AND PURPOSE Dysregulated tonic tension and calcium sensitization in blood vessels has frequently been observed in many cardiovascular diseases. Despite a huge therapeutic potential, little is known about natural products targeting tonic tension and calcium sensitization. EXPERIMENTAL APPROACH We screened natural products for inhibitory effects on vasoconstriction using the rat isolated thoracic aorta and found that an anthraquinone derivative, emodin, attenuated tonic tension. Organ bath system, primary vascular smooth muscle cells, confocal microscopy and Western blot analysis were employed to demonstrate the suppressive effects of emodin on PKCδ-mediated myosin phosphatase inhibition. KEY RESULTS Emodin, an active ingredient of Polygonum multiflorum extract, inhibited phenylephrine-induced vasoconstriction in rat isolated thoracic aorta, and inhibited vasoconstriction induced by 5-HT and endothelin-1. It also generally suppressed vasoconstrictions mediated by voltage-operated, store-operated calcium channels and intracellular calcium store. However, emodin did not affect agonist-induced calcium increases in primary smooth muscle cells. In contrast, post-treatment with emodin following phenylephrine stimulation potently suppressed tonic tension in rat aortic rings. Western blot analysis revealed that emodin inhibited phenylephrine-induced phospho-myosin light chain (pMLC) and the phosphorylation of myosin-targeting subunit and C-kinase-activated protein phosphatase-1 inhibitor (CPI-17). This was mediated by selective inhibition of PKCδ, whereas PKCα was not involved. CONCLUSION AND IMPLICATIONS Emodin attenuates tonic tension through the blockade of PKCδ and CPI-17-mediated MLC-phosphatase inhibition. This new mode of action for the suppression of tonic tension and structural insights into PKCδ inhibition revealed by emodin may provide new information for the development of modulators of tonic tension and for the treatment of hypertension.
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Affiliation(s)
- Kyung-Min Lim
- College of Pharmacy, Ewha Womans University, Seoul, Korea
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19
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García-García E, Gómez-González NE, Meseguer J, García-Ayala A, Mulero V. Histamine regulates the inflammatory response of the tunicate Styela plicata. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 46:382-391. [PMID: 24892817 DOI: 10.1016/j.dci.2014.05.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 05/25/2014] [Accepted: 05/26/2014] [Indexed: 06/03/2023]
Abstract
Histamine is stored inside hemocytes of the tunicate Styela plicata (Chordata, Tunicata, Ascidiacea), but no evidence on its role in the regulation of the immune response of this species has been reported. We examined whether histamine participated in the regulation of inflammation and host defense in S. plicata. The presence of histamine inside S. plicata hemocytes was confirmed by flow cytometry, and histamine release was detected by ELISA, after in vitro hemocyte stimulation with different PAMPs. In vitro hemocyte treatment with histamine, or specific histamine-receptor agonists, reduced their phagocytic ability. Injection of histamine into the tunic recruited hemocytes to the site of injection. Systemic injection of histamine, or the histamine-releasing agent compound 48/80, decreased the phagocytic ability of hemocytes. Histamine promoted the constriction of tunic hemolymph vessels in vivo, having a direct effect on vasoconstriction in tunic explants. These results provide for the first time clear evidence for the involvement of histamine in the regulation of inflammation and host defense in tunicates.
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Affiliation(s)
- Erick García-García
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; Instituto Murciano de Investigación Biosanitaria, 30100 Murcia, Spain
| | - Nuria E Gómez-González
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; Instituto Murciano de Investigación Biosanitaria, 30100 Murcia, Spain
| | - José Meseguer
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; Instituto Murciano de Investigación Biosanitaria, 30100 Murcia, Spain
| | - Alfonsa García-Ayala
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; Instituto Murciano de Investigación Biosanitaria, 30100 Murcia, Spain
| | - Victoriano Mulero
- Departamento de Biología Celular e Histología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain; Instituto Murciano de Investigación Biosanitaria, 30100 Murcia, Spain.
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20
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Gómez-González NE, García-García E, Montero J, García-Alcázar A, Meseguer J, García-Ayala A, Mulero V. Isolation of mast cells from the peritoneal exudate of the teleost fish gilthead sea bream (Sparus aurata L.). FISH & SHELLFISH IMMUNOLOGY 2014; 40:225-232. [PMID: 25047357 DOI: 10.1016/j.fsi.2014.07.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 06/03/2023]
Abstract
Inflammation is the first response of animals to infection or tissue damage. Sparus aurata (Perciformes) was the first fish species shown to possess histamine-containing mast cells at mucosal tissues. We report a separation protocol for obtaining highly enriched (over 95% purity) preparations of fish mast cells in high numbers (5-20 million mast cells per fish). The peritoneal exudate of S. aurata is composed of lymphocytes, acidophilic granulocytes, macrophages and mast cells. We separated the lymphocyte fraction through discontinuous density gradient centrifugation. The remaining cells were cultivated overnight in RPMI-1640 culture medium containing 5% fetal calf serum, which allowed macrophages to adhere to the cell culture flasks. Finally, acidophilic granulocytes were separated from the mast cells though a Magnetic-Activated Cell Separation (MACS) protocol, using a monoclonal antibody against these cells. The purity of mast cells-enriched fractions was analyzed by flow cytometry and by transmission electron microscopy. The functionality of purified mast cells was confirmed by the detection of histamine release by ELISA after stimulation with compound 48/80 and the induction of the pro-inflammatory cytokines IL-1β and IL-8 following stimulation with bacterial DNA. This fish mast cells separation protocol is a stepping stone for further studies addressing the evolution of vertebrate inflammatory mechanisms.
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Affiliation(s)
- Nuria Esther Gómez-González
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - Erick García-García
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - Jana Montero
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - Alicia García-Alcázar
- Instituto Español de Oceanografía, Planta de Cultivos Marinos, Ctra. de la Azohía s/n, 30860 Puerto de Mazarrón, Murcia, Spain
| | - José Meseguer
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - Alfonsa García-Ayala
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Campus Universitario de Espinardo, 30100 Murcia, Spain
| | - Victoriano Mulero
- Department of Cell Biology and Histology, Faculty of Biology, University of Murcia, IMIB-Arrixaca, Campus Universitario de Espinardo, 30100 Murcia, Spain.
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21
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Dougherty PJ, Nepiyushchikh ZV, Chakraborty S, Wang W, Davis MJ, Zawieja DC, Muthuchamy M. PKC activation increases Ca²⁺ sensitivity of permeabilized lymphatic muscle via myosin light chain 20 phosphorylation-dependent and -independent mechanisms. Am J Physiol Heart Circ Physiol 2014; 306:H674-83. [PMID: 24414065 DOI: 10.1152/ajpheart.00732.2013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The contractile activity of muscle cells lining the walls of collecting lymphatics is responsible for generating and regulating flow within the lymphatic system. Activation of PKC signaling contributes to the regulation of smooth muscle contraction by enhancing sensitivity of the contractile apparatus to Ca(2+). It is currently unknown whether PKC signaling contributes to the regulation of lymphatic muscle contraction. We hypothesized that the activation of PKC signaling would increase the sensitivity of the lymphatic myofilament to Ca(2+). To test this hypothesis, we determined the effects of PKC activation with phorbol esters [PMA or phorbol dibutyrate (PDBu)] on the contractile behavior of α-toxin-permeabilized rat mesenteric and cervical lymphatics or the thoracic duct. The addition of PMA or PDBu induced a significant increase in the contractile force of submaximally activated α-toxin-permeabilized lymphatic muscle independent of a change in intracellular Ca(2+) concentration, and the Ca(2+)-force relationship of lymphatic muscle was significantly left shifted, indicating greater myofilament Ca(2+) sensitivity. Phorbol esters increased the maximal rate of force development, whereas the rate of relaxation was reduced. Western blot and immunohistochemistry data indicated that the initial rapid increase in tension development after stimulation by PDBu was associated with myosin light chain (MLC)20 phosphorylation; however, the later, steady-state Ca(2+) sensitization of permeabilized lymphatic muscle was not associated with increased phosphorylation of MLC20 at Ser(19), 17-kDa C-kinase-potentiated protein phosphatase-1 inhibitor at Thr(38), or caldesmon at Ser(789). Thus, these data indicate that PKC-dependent Ca(2+) sensitization of lymphatic muscle may involve MLC20 phosphorylation-dependent and -independent mechanism(s).
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Affiliation(s)
- Patrick J Dougherty
- Department of Medical Physiology, College of Medicine, Texas A&M Health Science Center, College Station, Texas; and
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22
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The 2-arachidonoylglycerol effect on myosin light chain phosphorylation in human platelets. Biochimie 2013; 95:1620-8. [DOI: 10.1016/j.biochi.2013.05.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 05/10/2013] [Indexed: 12/13/2022]
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23
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Schjerning J, Uhrenholt TR, Svenningsen P, Vanhoutte PM, Skøtt O, Jensen BL, Hansen PBL. Histamine-dependent prolongation by aldosterone of vasoconstriction in isolated small mesenteric arteries of the mouse. Am J Physiol Heart Circ Physiol 2013; 304:H1094-102. [DOI: 10.1152/ajpheart.00524.2012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In arterioles, aldosterone counteracts the rapid dilatation (recovery) following depolarization-induced contraction. The hypothesis was tested that this effect of aldosterone depends on cyclooxygenase (COX)-derived products and/or nitric oxide (NO) synthase (NOS) inhibition. Recovery of the response to high K+ was observed in mesenteric arteries of wild-type and COX-2−/− mice but it was significantly diminished in preparations from endothelial NOS (eNOS)−/− mice. Aldosterone pretreatment inhibited recovery from wild-type and COX-2−/− mice. The NO donor sodium nitroprusside (SNP) restored recovery in arteries from eNOS−/− mice, and this was inhibited by aldosterone. Actinomycin-D abolished the effect of aldosterone, indicating a genomic effect. The effect was blocked by indomethacin and by the COX-1 inhibitor valeryl salicylate but not by NS-398 (10−6 mol/l) or the TP-receptor antagonist S18886 (10−7 mol/l). The effect of aldosterone on recovery in arteries from wild-type mice and the SNP-mediated dilatation in arteries from eNOS−/− mice was inhibited by the histamine H2 receptor antagonist cimetidine. RT-PCR showed expression of mast cell markers in mouse mesenteric arteries. The adventitia displayed granular cells positive for toluidine blue vital stain. Confocal microscopy of live mast cells showed loss of quinacrine fluorescence and swelling after aldosterone treatment, indicating degranulation. RT-PCR showed expression of mineralocorticoid receptors in mesenteric arteries and in isolated mast cells. These findings suggest that aldosterone inhibits recovery by stimulation of histamine release from mast cells along mesenteric arteries. The resulting activation of H2 receptors decreases the sensitivity to NO of vascular smooth muscle cells. Aldosterone may chronically affect vascular function through paracrine release of histamine.
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Affiliation(s)
- Jeppe Schjerning
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Denmark
| | - Torben R. Uhrenholt
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Denmark
| | - Per Svenningsen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Denmark
| | - Paul M. Vanhoutte
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, University of Hong Kong, Hong Kong, China; and
- Department of Clinical Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Ole Skøtt
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Denmark
| | - Boye L. Jensen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Denmark
| | - Pernille B. L. Hansen
- Department of Cardiovascular and Renal Research, Institute of Molecular Medicine, University of Southern Denmark, Denmark
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Kim KM, Adyshev DM, Kása A, Zemskov EA, Kolosova IA, Csortos C, Verin AD. Putative protein partners for the human CPI-17 protein revealed by bacterial two-hybrid screening. Microvasc Res 2013; 88:19-24. [PMID: 23583905 DOI: 10.1016/j.mvr.2013.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 02/26/2013] [Accepted: 04/01/2013] [Indexed: 01/06/2023]
Abstract
We have previously demonstrated that PKC-potentiated inhibitory protein of protein phosphatase-1 (CPI-17) is expressed in lung endothelium. CPI-17, a specific inhibitor of myosin light chain phosphatase (MLCP), is involved in the endothelial cytoskeletal and barrier regulation. In this paper, we report the identification of fourteen putative CPI-17 interacting proteins in the lung using BacterioMatch Two-Hybrid System. Five of them: plectin 1 isoform 1, alpha II spectrin, OK/SW-CL.16, gelsolin isoform a, and junction plakoglobin are involved in actin cytoskeleton organization and cell adhesion, suggesting possible significance of these binding partners in CPI-17-mediated cytoskeletal reorganization of endothelial cells. Furthermore, we confirmed the specific interaction between plakoglobin and CPI-17, which is affected by the phosphorylation status of CPI-17 in human lung microvascular endothelial cells.
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Affiliation(s)
- Kyung-mi Kim
- Vascular Biology Center, Georgia Health Sciences University, Augusta, GA, USA
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25
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GATA-6 and NF-κB activate CPI-17 gene transcription and regulate Ca2+ sensitization of smooth muscle contraction. Mol Cell Biol 2012; 33:1085-102. [PMID: 23275439 DOI: 10.1128/mcb.00626-12] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Protein kinase C (PKC)-potentiated inhibitory protein of 17 kDa (CPI-17) inhibits myosin light chain phosphatase, altering the levels of myosin light chain phosphorylation and Ca(2+) sensitivity in smooth muscle. In this study, we characterized the CPI-17 promoter and identified binding sites for GATA-6 and nuclear factor kappa B (NF-κB). GATA-6 and NF-κB upregulated CPI-17 expression in cultured human and mouse bladder smooth muscle (BSM) cells in an additive manner. CPI-17 expression was decreased upon GATA-6 silencing in cultured BSM cells and in BSM from NF-κB knockout (KO) mice. Moreover, force maintenance by BSM strips from KO mice was decreased compared with the force maintenance of BSM strips from wild-type mice. GATA-6 and NF-κB overexpression was associated with CPI-17 overexpression in BSM from men with benign prostatic hyperplasia (BPH)-induced bladder hypertrophy and in a mouse model of bladder outlet obstruction. Thus, aberrant expression of NF-κB and GATA-6 deregulates CPI-17 expression and the contractile function of smooth muscle. Our data provide insight into how GATA-6 and NF-κB mediate CPI-17 transcription, PKC-mediated signaling, and BSM remodeling associated with lower urinary tract symptoms in patients with BPH.
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26
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Singh J, Rattan S. Bioengineered human IAS reconstructs with functional and molecular properties similar to intact IAS. Am J Physiol Gastrointest Liver Physiol 2012; 303:G713-22. [PMID: 22790596 PMCID: PMC3468534 DOI: 10.1152/ajpgi.00112.2012] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Because of its critical importance in rectoanal incontinence, we determined the feasibility to reconstruct internal anal sphincter (IAS) from human IAS smooth muscle cells (SMCs) with functional and molecular attributes similar to the intact sphincter. The reconstructs were developed using SMCs from the circular smooth muscle layer of the human IAS, grown in smooth muscle differentiation media under sterile conditions in Sylgard-coated tissue culture plates with central Sylgard posts. The basal tone in the reconstructs and its changes were recorded following 0 Ca(2+), KCl, bethanechol, isoproterenol, protein kinase C (PKC) activator phorbol 12,13-dibutyrate, and Rho kinase (ROCK) and PKC inhibitors Y-27632 and Gö-6850, respectively. Western blot (WB), immunofluorescence (IF), and immunocytochemical (IC) analyses were also performed. The reconstructs developed spontaneous tone (0.68 ± 0.26 mN). Bethanechol (a muscarinic agonist) and K(+) depolarization produced contraction, whereas isoproterenol (β-adrenoceptor agonist) and Y-27632 produced a concentration-dependent decrease in the tone. Maximal decrease in basal tone with Y-27632 and Gö-6850 (each 10(-5) M) was 80.45 ± 3.29 and 17.76 ± 3.50%, respectively. WB data with the IAS constructs' SMCs revealed higher levels of RhoA/ROCK, protein kinase C-potentiated inhibitor or inhibitory phosphoprotein for myosin phosphatase (CPI-17), phospho-CPI-17, MYPT1, and 20-kDa myosin light chain vs. rectal smooth muscle. WB, IF, and IC studies of original SMCs and redispersed from the reconstructs for the relative distribution of different signal transduction proteins confirmed the feasibility of reconstruction of IAS with functional properties similar to intact IAS and demonstrated the development of myogenic tone with critical dependence on RhoA/ROCK. We conclude that it is feasible to bioengineer IAS constructs using human IAS SMCs that behave like intact IAS.
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Affiliation(s)
- Jagmohan Singh
- Division of Gastroenterology and Hepatology, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Satish Rattan
- Division of Gastroenterology and Hepatology, Department of Medicine, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania
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27
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Lontay B, Pál B, Serfőző Z, Kőszeghy Á, Szücs G, Rusznák Z, Erdődi F. Protein phosphatase-1M and Rho-kinase affect exocytosis from cortical synaptosomes and influence neurotransmission at a glutamatergic giant synapse of the rat auditory system. J Neurochem 2012; 123:84-99. [PMID: 22817114 DOI: 10.1111/j.1471-4159.2012.07882.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein phosphatase-1M (PP1M, myosin phosphatase) consists of a PP1 catalytic subunit (PP1c) and the myosin phosphatase target subunit-1 (MYPT1). RhoA-activated kinase (ROK) regulates PP1M via inhibitory phosphorylation of MYPT1. Using multidisciplinary approaches, we have studied the roles of PP1M and ROK in neurotransmission. Electron microscopy demonstrated the presence of MYPT1 and ROK in both pre- and post-synaptic terminals. Tautomycetin (TMC), a PP1-specific inhibitor, decreased the depolarization-induced exocytosis from cortical synaptosomes. trans-4-[(1R)-1-aminoethyl]-N-4-pyridinylcyclohexanecarboxamide dihydrochloride, a ROK-specific inhibitor, had the opposite effect. Mass spectrometry analysis identified several MYPT1-bound synaptosomal proteins, of which interactions of synapsin-I, syntaxin-1, calcineurin-A subunit, and Ca(2+) /calmodulin-dependent kinase II with MYPT1 were confirmed. In intact synaptosomes, TMC increased, whereas Y27632 decreased the phosphorylation levels of MYPT1(Thr696) , myosin-II light chain(Ser19) , synapsin-I(Ser9) , and syntaxin-1(Ser14) , indicating that PP1M and ROK influence their phosphorylation status. Confocal microscopy indicated that MYPT1 and ROK are present in the rat ventral cochlear nucleus both pre- and post-synaptically. Analysis of the neurotransmission in an auditory glutamatergic giant synapse demonstrated that PP1M and ROK affect neurotransmission via both pre- and post-synaptic mechanisms. Our data suggest that both PP1M and ROK influence synaptic transmission, but further studies are needed to give a full account of their mechanism of action.
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Affiliation(s)
- Beáta Lontay
- Department of Medical Chemistry and Cell Biology and Signaling Research Group of the Hungarian Academy of Sciences, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary
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Wright DB, Tripathi S, Sikarwar A, Santosh KT, Perez-Zoghbi J, Ojo OO, Irechukwu N, Ward JPT, Schaafsma D. Regulation of GPCR-mediated smooth muscle contraction: implications for asthma and pulmonary hypertension. Pulm Pharmacol Ther 2012; 26:121-31. [PMID: 22750270 DOI: 10.1016/j.pupt.2012.06.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 06/15/2012] [Accepted: 06/18/2012] [Indexed: 11/28/2022]
Abstract
Contractile G-protein-coupled receptors (GPCRs) have emerged as key regulators of smooth muscle contraction, both under healthy and diseased conditions. This brief review will discuss some key topics and novel insights regarding GPCR-mediated airway and vascular smooth muscle contraction as discussed at the 7th International Young Investigators' Symposium on Smooth Muscle (2011, Winnipeg, Manitoba, Canada) and will in particular focus on processes driving Ca(2+)-mobilization and -sensitization.
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Affiliation(s)
- D B Wright
- Department of Asthma, Allergy, and Lung Biology, King's College, London, United Kingdom
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29
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Tazzeo T, Bates G, Roman HN, Lauzon AM, Khasnis MD, Eto M, Janssen LJ. Caffeine relaxes smooth muscle through actin depolymerization. Am J Physiol Lung Cell Mol Physiol 2012; 303:L334-42. [PMID: 22683573 DOI: 10.1152/ajplung.00103.2012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Caffeine is sometimes used in cell physiological studies to release internally stored Ca(2+). We obtained evidence that caffeine may also act through a different mechanism that has not been previously described and sought to examine this in greater detail. We ruled out a role for phosphodiesterase (PDE) inhibition, since the effect was 1) not reversed by inhibiting PKA or adenylate cyclase; 2) not exacerbated by inhibiting PDE4; and 3) not mimicked by submillimolar caffeine nor theophylline, both of which are sufficient to inhibit PDE. Although caffeine is an agonist of bitter taste receptors, which in turn mediate bronchodilation, its relaxant effect was not mimicked by quinine. After permeabilizing the membrane using β-escin and depleting the internal Ca(2+) store using A23187, we found that 10 mM caffeine reversed tone evoked by direct application of Ca(2+), suggesting it functionally antagonizes the contractile apparatus. Using a variety of molecular techniques, we found that caffeine did not affect phosphorylation of myosin light chain (MLC) by MLC kinase, actin-filament motility catalyzed by MLC kinase, phosphorylation of CPI-17 by either protein kinase C or RhoA kinase, nor the activity of MLC-phosphatase. However, we did obtain evidence that caffeine decreased actin filament binding to phosphorylated myosin heads and increased the ratio of globular to filamentous actin in precontracted tissues. We conclude that, in addition to its other non-RyR targets, caffeine also interferes with actin function (decreased binding by myosin, possibly with depolymerization), an effect that should be borne in mind in studies using caffeine to probe excitation-contraction coupling in smooth muscle.
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Affiliation(s)
- Tracy Tazzeo
- Firestone Institute for Respiratory Health, St. Joseph’s Hospital and the Department of Medicine, McMaster University, Hamilton, Ontario, Canada
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Rattan S, Singh J. RhoA/ROCK pathway is the major molecular determinant of basal tone in intact human internal anal sphincter. Am J Physiol Gastrointest Liver Physiol 2012; 302:G664-75. [PMID: 22241857 PMCID: PMC3330775 DOI: 10.1152/ajpgi.00430.2011] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The knowledge of molecular control mechanisms underlying the basal tone in the intact human internal anal sphincter (IAS) is critical for the pathophysiology and rational therapy for a number of debilitating rectoanal motility disorders. We determined the role of RhoA/ROCK and PKC pathways by comparing the effects of ROCK- and PKC-selective inhibitors Y 27632 and Gö 6850 (10(-8) to 10(-4) M), respectively, on the basal tone in the IAS vs. the rectal smooth muscle (RSM). Western blot studies were performed to determine the levels of RhoA/ROCK II, PKC-α, MYPT1, CPI-17, and MLC(20) in the unphosphorylated and phosphorylated forms, in the IAS vs. RSM. Confocal microscopic studies validated the membrane distribution of ROCK II. Finally, to confirm a direct relationship, we examined the enzymatic activities and changes in the basal IAS tone and p-MYPT1, p-CPI-17, and p-MLC(20), before and after Y 27632 and Gö 6850. Data show higher levels of RhoA/ROCK II and related downstream signal transduction proteins in the IAS vs. RSM. In addition, data show a significant correlation between the active RhoA/ROCK levels, ROCK enzymatic activity, downstream proteins, and basal IAS tone, before and after ROCK inhibitor. From these data we conclude 1) RhoA/ROCK and downstream signaling are constitutively active in the IAS, and this pathway (in contrast with PKC) is the critical determinant of the basal tone in intact human IAS; and 2) RhoA and ROCK are potential therapeutic targets for a number of rectoanal motility disorders for which currently there is no satisfactory treatment.
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Affiliation(s)
- Satish Rattan
- Dept. of Medicine, Division of Gastroenterology & Hepatology, Philadelphia, PA 19107, USA.
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Ruiz-Loredo AY, López E, López-Colomé AM. Thrombin stimulates stress fiber assembly in RPE cells by PKC/CPI-17-mediated MLCP inactivation. Exp Eye Res 2012; 96:13-23. [DOI: 10.1016/j.exer.2012.01.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 01/11/2012] [Accepted: 01/17/2012] [Indexed: 12/29/2022]
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Ihara E, Chappellaz M, Turner SR, MacDonald JA. The contribution of protein kinase C and CPI-17 signaling pathways to hypercontractility in murine experimental colitis. Neurogastroenterol Motil 2012; 24:e15-26. [PMID: 22093175 DOI: 10.1111/j.1365-2982.2011.01821.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Colonic smooth muscle contractility is altered in colitis, and several protein kinase pathways can mediate colonic smooth muscle contraction. In the present study, we investigated whether protein kinase C (PKC) pathways also play a role in colonic hypercontractility observed during T(H) 2 colitis in BALB/c mice. METHODS Colitis was induced in BALB/c mice by provision of 5% dextran sodium sulfate (DSS) for 7 days. Changes in smooth muscle contractility were examined using dissected circular smooth muscle preparations from the distal colon. The contribution of conventional and novel PKC isozymes to the hypercontractile response was examined with pharmacological PKC inhibitors. Western blot analyses were used to examine protein expression and phosphorylation changes. KEY RESULTS Colonic smooth muscle was associated with inflammation-induced hypercontractility and altered PKC expression. Carbachol-induced peak (phasic) and sustained (tonic) contractions were increased. Chelerythrine was the most effective PKC inhibitor of both phasic and tonic contractions. There was no general difference in the percent contribution of conventional and novel PKC isozymes toward the DSS-induced hypercontractility, but inhibition of sustained force with GF109203x was higher for inflamed muscle. The CPI-17 phosphorylation was equally suppressed in both normal and DSS conditions by Gö6976 and chelerythrine, but only for the phasic component of contraction. CONCLUSIONS & INFERENCES The outcomes suggest that both conventional and novel PKC isozymes contribute to the phasic and tonic contractile components of BALB/c colonic circular smooth muscle under normal conditions, with novel PKC isozymes having a greater contribution to the tonic contraction. However, no effect of inflammation was observed on the relative contribution of PKC and CPI-17 toward the observed hypercontractility.
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Affiliation(s)
- E Ihara
- Smooth Muscle and Gastrointestinal Research Groups, Department of Biochemistry & Molecular Biology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada
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Bayguinov O, Dwyer L, Kim H, Marklew A, Sanders KM, Koh SD. Contribution of Rho-kinase to membrane excitability of murine colonic smooth muscle. Br J Pharmacol 2011; 163:638-48. [PMID: 21265824 DOI: 10.1111/j.1476-5381.2011.01241.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND AND PURPOSE The Rho-kinase pathway regulates agonist-induced contractions in several smooth muscles, including the intestine, urinary bladder and uterus, via dynamic changes in the Ca(2+) sensitivity of the contractile apparatus. However, there is evidence that Rho-kinase also modulates other cellular effectors such as ion channels. EXPERIMENTAL APPROACH We examined the regulation of colonic smooth muscle excitability by Rho-kinase using conventional microelectrode recording, isometric force measurements and patch-clamp techniques. KEY RESULTS The Rho-kinase inhibitors, Y-27632 and H-1152, decreased nerve-evoked on- and off-contractions elicited at a range of frequencies and durations. The Rho-kinase inhibitors decreased the spontaneous contractions and the responses to carbachol and substance P independently of neuronal inputs, suggesting Y-27632 acts directly on smooth muscle. The Rho-kinase inhibitors significantly reduced the depolarization in response to carbachol, an effect that cannot be due to regulation of Ca(2+) sensitization. Patch-clamp experiments showed that Rho-kinase inhibitors reduce GTPγS-activated non-selective cation currents. CONCLUSIONS AND IMPLICATIONS The Rho-kinase inhibitors decreased contractions evoked by nerve stimulation, carbachol and substance P. These effects were not solely due to inhibition of the Ca(2+) sensitization pathway, as the Rho-kinase inhibitors also inhibited the non-selective cation conductances activated by excitatory transmitters. Thus, Rho-kinase may regulate smooth muscle excitability mechanisms by regulating non-selective cation channels as well as changing the Ca(2+) sensitivity of the contractile apparatus.
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Affiliation(s)
- O Bayguinov
- Department of Physiology and Cell Biology, University of Nevada Reno, School of Medicine, USA
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Obara K, Ukai K, Ishikawa T. Mechanism of potentiation by tea epigallocatechin of contraction in porcine coronary artery: The role of protein kinase Cδ-mediated CPI-17 phosphorylation. Eur J Pharmacol 2011; 668:414-8. [DOI: 10.1016/j.ejphar.2011.07.028] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Revised: 06/09/2011] [Accepted: 07/14/2011] [Indexed: 02/01/2023]
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Singh J, Maxwell PJ, Rattan S. Immunocytochemical evidence for PDBu-induced activation of RhoA/ROCK in human internal anal sphincter smooth muscle cells. Am J Physiol Gastrointest Liver Physiol 2011; 301:G317-25. [PMID: 21566015 PMCID: PMC3154599 DOI: 10.1152/ajpgi.00084.2011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Studies were performed to determine the unknown status of PKC and RhoA/ROCK in the phorbol 12,13-dibutyrate (PDBu)-stimulated state in the human internal anal sphincter (IAS) smooth muscle cells (SMCs). We determined the effects of PDBu (10(-7) M), the PKC activator, on PKCα and RhoA and ROCK II translocation in the human IAS SMCs. We used immunocytochemistry and fluorescence microcopy in the basal state, following PDBu, and before and after PKC inhibitor calphostin C (10(-6) M), cell-permeable RhoA inhibitor C3 exoenzyme (2.5 μg/ml), and ROCK inhibitor Y 27632 (10(-6) M). We also determined changes in the SMC lengths via computerized digital micrometry. In the basal state PKCα was distributed almost uniformly throughout the cell, whereas RhoA and ROCK II were located in the higher intensities toward the periphery. PDBu caused significant translocation of PKCα, RhoA, and ROCK II. PDBu-induced translocation of PKCα was attenuated by calphostin C and not by C3 exoenzyme and Y 27632. However, PDBu-induced translocation of RhoA was blocked by C3 exoenzyme, and that of ROCK II was attenuated by both C3 exoenzyme and Y 27632. Contraction of the human IAS SMCs caused by PDBu in parallel with RhoA/ROCK II translocation was attenuated by C3 exoenzyme and Y 27632 but not by calphostin C. In human IAS SMCs RhoA/ROCK compared with PKC are constitutively active, and contractility by PDBu is associated with RhoA/ROCK activation rather than PKC. The relative contribution of RhoA/ROCK vs. PKC in the pathophysiology and potential therapy for the IAS dysfunction remains to be determined.
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Affiliation(s)
- Jagmohan Singh
- Department of Medicine, Division of Gastroenterology and Hepatology, and Department of Surgery, Division of Colon and Rectal Surgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Pinckney J. Maxwell
- Department of Medicine, Division of Gastroenterology and Hepatology, and Department of Surgery, Division of Colon and Rectal Surgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Satish Rattan
- Department of Medicine, Division of Gastroenterology and Hepatology, and Department of Surgery, Division of Colon and Rectal Surgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
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Seok YM, Cho HJ, Cha BY, Woo JT, Kim IK. Honokiol attenuates vascular contraction through the inhibition of the RhoA/Rho-kinase signalling pathway in rat aortic rings. J Pharm Pharmacol 2011; 63:1244-51. [DOI: 10.1111/j.2042-7158.2011.01332.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Abstract
Objectives
Honokiol is a small-molecule polyphenol isolated from the species Magnolia obovata. We hypothesized that honokiol attenuated vascular contractions through the inhibition of the RhoA/Rho-kinase signalling pathway.
Methods
Rat aortic rings were denuded of endothelium, mounted in organ baths, and subjected to contraction or relaxation. Phosphorylation of 20 kDa myosin light chains (MLC20), myosin phosphatase targeting subunit 1 (MYPT1) and protein kinase C (PKC)-potentiated inhibitory protein for heterotrimeric myosin light chain phosphatase (MLCP) of 17 kDa (CPI17) were examined by immunoblot. We also measured the amount of guanosine triphosphate RhoA as a marker for RhoA activation.
Key findings
Pretreatment with honokiol dose-dependently inhibited the concentration–response curves in response to sodium fluoride (NaF) or thromboxane A2 agonist U46619. Honokiol decreased the phosphorylation levels of MLC20, MYPT1Thr855 and CPI17Thr38 as well as the activation of RhoA induced by 8.0 mm NaF or 30 nm U46619.
Conclusions
These results demonstrated that honokiol attenuated vascular contraction through the inhibition of the RhoA/Rho-kinase signalling pathway.
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Affiliation(s)
- Young Mi Seok
- Cardiovascular Research Institute, Republic of Korea
| | | | - Byung-Yoon Cha
- Department of Biological Chemistry and Research Institute for Biological Functions, Chubu University, Kasugai, Aichi, Japan
| | - Je-Tae Woo
- Department of Biological Chemistry and Research Institute for Biological Functions, Chubu University, Kasugai, Aichi, Japan
- Department of Nutriproteomics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - In Kyeom Kim
- Cardiovascular Research Institute, Republic of Korea
- Department of Pharmacology, Republic of Korea
- CMRI, Kyungpook National University School of Medicine, Daegu, Republic of Korea
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Rho-kinase inhibition attenuates calcium-induced contraction in β-escin but not Triton X-100 permeabilized rabbit femoral artery. J Muscle Res Cell Motil 2011; 32:77-88. [PMID: 21706258 DOI: 10.1007/s10974-011-9253-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Accepted: 05/31/2011] [Indexed: 01/09/2023]
Abstract
K+-depolarization (KCl) of smooth muscle has long been known to cause Ca2+-dependent contraction, but only recently has this G protein-coupled receptor (GPCR)-independent stimulus been associated with rhoA kinase (ROCK)-dependent myosin light chain (MLC) phosphatase inhibition and Ca2+ sensitization. This study examined effects of ROCK inhibition on the concentration-response curves (CRCs) generated in femoral artery by incrementally adding increasing concentrations of KCl to intact tissues, and Ca2+ to tissues permeabilized with Triton X-100, β-escin and α-toxin. For a comparison, tissue responses were assessed also in the presence of protein kinase C (PKC) and MLC kinase inhibition. The ROCK inhibitor H-1152 induced a strong concentration-dependent inhibition of a KCl CRC. A relatively low GF-109203X concentration (1 μM) sufficient to inhibit conventional PKC isotypes also inhibited the KCl CRC but did not affect the maximum tension. ROCK inhibitors had no effect on the Ca2+ CRC induced in Triton X-100 or α-toxin permeabilized tissues, but depressed the maximum contraction induced in β-escin permeabilized tissue. GF-109203X at 1 μM depressed the maximum Ca2+-dependent contraction induced in α-toxin permeabilized tissue and had no effect on the Ca2+ CRC induced in Triton X-100 permeabilized tissue. The MLC kinase inhibitor wortmannin (1 μM) strongly depression the Ca2+ CRCs in tissues permeabilized with Triton X-100, α-toxin and β-escin. H-1152 inhibited contractions induced by a single exposure to a submaximum [Ca2+] (pCa 6) in both rabbit and mouse femoral arteries. These data indicate that β-escin permeabilized muscle preserves GPCR-independent, Ca2+- and ROCK-dependent, Ca2+ sensitization.
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Sakamoto K, Nakahara T, Ishii K. Rho-Rho kinase pathway is involved in the protective effect of early ischemic preconditioning in the rat heart. Biol Pharm Bull 2011; 34:156-9. [PMID: 21212536 DOI: 10.1248/bpb.34.156] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
It has been shown that p38 mitogen-activated protein (MAP) kinase is absolutely necessary for the cardioprotection of early ischemic preconditioning in the heart. Reorganization of actin cytoskeleton after translocation of HSP27, which is mediated by p38 MAP kinase, was reported to be necessary for the cardioprotective effect of early ischemic preconditioning. Although Rho and Rho kinase are reported to regulate reorganization of actin filaments, it is unknown whether Rho-Rho kinase pathway is involved in the cardioprotective effect of early ischemic preconditioning. The aim of the present study is to determine the involvement of Rho-Rho kinase pathway in the protective effect of early ischemic preconditioning in the rat hearts. Dominant-negative Rho significantly reduced the hypoxia-reoxygenation-induced activation of p38 MAP kinase, and constitutive active Rho activated p38 MAP kinase in rat myoblast H9c2 cells. Y-27632, a specific Rho kinase inhibitor, concentration-dependently attenuated the post-ischemic recovery of left ventricular developed pressure by early ischemic preconditioning. Thus, Rho-Rho kinase pathway is, at least in part, involved in the mechanism of early ischemic preconditioning.
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Affiliation(s)
- Kenji Sakamoto
- Department of Molecular Pharmacology, School of Pharmaceutical Sciences, Kitasato University, Tokyo 108–8641, Japan.
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Seok YM, Azam MA, Okamoto Y, Sato A, Yoshioka K, Maeda M, Kim I, Takuwa Y. Enhanced Ca2+-Dependent Activation of Phosphoinositide 3-Kinase Class IIα Isoform-Rho Axis in Blood Vessels of Spontaneously Hypertensive Rats. Hypertension 2010; 56:934-41. [DOI: 10.1161/hypertensionaha.110.160853] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Young Mi Seok
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - Mohammed Ali Azam
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - Yasuo Okamoto
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - Atsushi Sato
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - Kazuaki Yoshioka
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - Masataka Maeda
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - InKyeom Kim
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
| | - Yoh Takuwa
- From the Department of Physiology (Y.M.S., M.A.A., Y.O., A.S., K.Y., M.M., Y.T.), Kanazawa University Graduate School of Medicine, Kanazawa, Japan; Department of Pharmacology (I.K.), Kyungpook National University School of Medicine, Daegu, Korea
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Wang H, Owens C, Chandra N, Conaway MR, Brautigan DL, Theodorescu D. Phosphorylation of RalB is important for bladder cancer cell growth and metastasis. Cancer Res 2010; 70:8760-9. [PMID: 20940393 DOI: 10.1158/0008-5472.can-10-0952] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
RalA and RalB are monomeric G proteins that are 83% identical in amino acid sequence but have paralogue-specific effects on cell proliferation, metastasis, and apoptosis. Using in vitro kinase assays and phosphosite-specific antibodies, here we show phosphorylation of RalB by protein kinase C (PKC) and RalA by protein kinase A. We used mass spectrometry and site-directed mutagenesis to identify S198 as the primary PKC phosphorylation site in RalB. Phorbol ester [phorbol 12-myristate 13-acetate (PMA)] treatment of human bladder carcinoma cells induced S198 phosphorylation of stably expressed FLAG-RalB as well as endogenous RalB. PMA treatment caused RalB translocation from the plasma membrane to perinuclear regions in a S198 phosphorylation-dependent manner. Using RNA interference depletion of RalB followed by rescue with wild-type RalB or RalB(S198A) as well as overexpression of wild-type RalB or RalB(S198A) with and without PMA stimulation, we show that phosphorylation of RalB at S198 is necessary for actin cytoskeletal organization, anchorage-independent growth, cell migration, and experimental lung metastasis of T24 or UMUC3 human bladder cancer cells. In addition, UMUC3 cells transfected with a constitutively active RalB(G23V) exhibited enhanced subcutaneous tumor growth, whereas those transfected with phospho-deficient RalB(G23V-S198A) were indistinguishable from control cells. Our data show that RalA and RalB are phosphorylated by different kinases, and RalB phosphorylation is necessary for in vitro cellular functions and in vivo tumor growth and metastasis.
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Affiliation(s)
- Hong Wang
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
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Mbikou P, Fajmut A, Brumen M, Roux E. Contribution of Rho kinase to the early phase of the calcium-contraction coupling in airway smooth muscle. Exp Physiol 2010; 96:240-58. [PMID: 20870731 DOI: 10.1113/expphysiol.2010.054635] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We investigated theoretically and experimentally the role of Rho kinase (RhoK) in Ca(2+)-contraction coupling in rat airways. Isometric contraction was measured on tracheal, extrapulmonary and intrapulmonary bronchial rings. Intracellular [Ca(2+)] was recorded in freshly isolated tracheal myocytes. Stimulation by carbachol (0.3 and 10 μm) and 50 mm external KCl induced a short-time, Hill-shaped contraction obtained within 90 s, followed by a sustained or an additional delayed contraction. Responses of [Ca(2+)](i) to acetylcholine consisted in a fast peak followed by a plateau and, in 42% of the cells, superimposed Ca(2+) oscillations. The RhoK inhibitor Y27632 (10 μm) did not alter the [Ca(2+)](i) response. Whatever the agonist, Y27632 did not modify the basal tension but decreased the amplitude of the short-duration response, without altering the additional delayed contraction. The Myosin Light Chain Phosphatase (MLCP) inhibitor calyculin A increased the basal tension and abolished the effect of RhoK. KN93 (Ca(2+)-calmodulin-dependent protein kinase II inhibitor) and DIDS (inhibitor of Ca(2+)-activated Cl(-) channels) had no influence on the RhoK effect. We built a theoretical model of Ca(2+)-dependent active/inactive RhoK ratio and subsequent RhoK-dependent MLCP inactivation, which was further coupled with a four-state model of the contractile apparatus and Ca(2+)-dependent MLCK activation. The model explains the time course of the short-duration contraction and the role of RhoK by Ca(2+)-dependent activation of MLCK and RhoK, which inactivates MLCP. Oscillatory and non-oscillatory [Ca(2+)](i) responses result in a non-oscillatory contraction, the amplitude of which is encoded by the plateau value and oscillation frequency. In conclusion, Ca(2+)-dependent but CaMK II-independent RhoK activation contributes to the early phase of the contractile response via MLCP inhibition.
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Affiliation(s)
- Prisca Mbikou
- Laboratoire de Physiologie Cellulaire Respiratoire, INSERM U885, Université Victor Segalen Bordeaux 2, 146 rue Léo-Saignat, Bordeaux cedex, France
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G protein-mediated Ca²+-sensitization of CPI-17 phosphorylation in arterial smooth muscle. Biochem Biophys Res Commun 2010; 401:75-8. [PMID: 20833141 DOI: 10.1016/j.bbrc.2010.09.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2010] [Accepted: 09/06/2010] [Indexed: 11/21/2022]
Abstract
CPI-17 is a unique phosphoprotein that specifically inhibits myosin light chain phosphatase in smooth muscle and plays an essential role in agonist-induced contraction. To elucidate the in situ mechanism for G protein-mediated Ca²+-sensitization of CPI-17 phosphorylation, α-toxin-permeabilized arterial smooth muscle strips were used to monitor both force development and CPI-17 phosphorylation in response to GTPγS with varying Ca²+ concentrations. CPI-17 phosphorylation increased at unphysiologically high Ca²+ levels of pCa ≤ 6. GTPγS markedly enhanced the Ca²+ sensitivity of CPI-17 steady-state phosphorylation but had no enhancing effect under Ca²+-free conditions, while the potent PKC activator PDBu increased CPI-17 phosphorylation regardless of Ca²+ concentration. CPI-17 phosphorylation induced by pCa 4.5 alone was markedly inhibited by the presence of PKC inhibitor but not ROCK inhibitor. In the presence of calyculin A, a potent PP1/PP2A phosphatase inhibitor, CPI-17 phosphorylation increased with time even under Ca²+-free conditions. Furthermore, as Ca²+ concentration increased, so did CPI-17 phosphorylation rate. GTPγS markedly enhanced the rate of phosphorylation of CPI-17 at a given Ca²+. In the absence of calyculin A, either steady-state phosphorylation of CPI-17 under Ca²+-free conditions in the presence of GTPγS or at pCa 6.7 in the absence of GTPγS was negligible, suggesting a high intrinsic CPI-17 phosphatase activity. In conclusion, cooperative increases in Ca²+ and G protein activation are required for a significant activation of total kinases that phosphorylate CPI-17, which together overcome CPI-17 phosphatase activity and effectively increase the Ca²+ sensitivity of CPI-17 phosphorylation and smooth muscle contraction.
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Yang E, Jeon SB, Baek I, Song MJ, Yoon YR, Kim IK. Fluoride induces vascular contraction through activation of RhoA/Rho kinase pathway in isolated rat aortas. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2010; 29:290-296. [PMID: 21787615 DOI: 10.1016/j.etap.2010.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 01/31/2010] [Accepted: 02/11/2010] [Indexed: 05/31/2023]
Abstract
We hypothesized that fluoride induces vascular contraction through activation of the RhoA/Rho kinase pathway in isolated rat aortas. Rat aortic rings were mounted in organ baths and contracted with sodium fluoride (NaF). We measured the amount of GTP-RhoA as well as vascular tension. We also determined the level of phosphorylation of the myosin light chain (MLC(20)), myosin phosphatase targeting subunit 1 (MYPT1) and PKC-potentiated inhibitory protein for heterotrimeric MLCP of 17kDa (CPI17). In both physiological salt solution and Ca(2+)-free solution, NaF increased vascular tension and MLC(20) phosphorylation in dose-dependent manners. NaF increased not only phosphorylation level of MYPT1(Thr855) and CPI17(Thr38), but also the amount of GTP-RhoA. Both H1152 and Y27632, inhibitors of Rho kinase, but not Ro31-8220, an inhibitor of PKC, attenuated NaF-induced contraction and phosphorylation level of MLC(20), MYPT1(Thr855) and CPI17(Thr38). In conclusion, fluoride induces vascular contraction through activation of the RhoA/Rho kinase pathway.
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Affiliation(s)
- Enyue Yang
- Department of Pharmacology, Kyungpook National University School of Medicine, Daegu 700-422, Republic of Korea
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Song MJ, Baek I, Jeon SB, Seo M, Kim YH, Cui S, Jeong YS, Lee IJ, Shin DH, Hwang YH, Kim IK. Effects of glyceollin I on vascular contraction in rat aorta. Naunyn Schmiedebergs Arch Pharmacol 2010; 381:517-28. [DOI: 10.1007/s00210-010-0513-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Accepted: 03/08/2010] [Indexed: 12/15/2022]
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Puetz S, Lubomirov LT, Pfitzer G. Regulation of smooth muscle contraction by small GTPases. Physiology (Bethesda) 2010; 24:342-56. [PMID: 19996365 DOI: 10.1152/physiol.00023.2009] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Next to changes in cytosolic [Ca(2+)], members of the Rho subfamily of small GTPases, in particular Rho and its effector Rho kinase, also known as ROK or ROCK, emerged as key regulators of smooth muscle function in health and disease. In this review, we will focus on the regulation of the contractile machinery by Rho/ROK signaling and its interaction with PKC and cyclic nucleotide signaling. We will briefly discuss the emerging evidence that remodeling of cortical actin is necessary for contraction.
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Affiliation(s)
- Sandra Puetz
- Institut für Vegetative Physiologie, Universitaet Koeln, Koeln, Germany,
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Liu CQ, Wong SL, Leung FP, Tian XY, Lau CW, Lu L, Yao X, Chen ZY, Yao T, Huang Y. Prostanoid TP receptor-mediated impairment of cyclic AMP-dependent vasorelaxation is reversed by phosphodiesterase inhibitors. Eur J Pharmacol 2010; 632:45-51. [PMID: 20096281 DOI: 10.1016/j.ejphar.2010.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Revised: 12/18/2009] [Accepted: 01/12/2010] [Indexed: 11/18/2022]
Abstract
Activation of the thromboxane prostanoid (TP) receptor produces potent vasoconstriction, which contributes to the increased vascular tone and blood pressure. The present study was designed to examine the hypothesis that stimulation of prostanoid TP receptors impairs endothelium-independent relaxations to cyclic AMP-elevating agents via increasing the activity of phosphodiesterases (PDEs). Rat carotid arteries without endothelium were isolated and suspended in myograph for the measurement of changes in isometric tension; the tissue content of cyclic AMP was assayed by enzyme immunoassay kit; and prostanoid TP receptor was detected in vascular wall by immunohistochemistry and Western blot. In phenylephrine-contracted rings without endothelium, relaxations induced by isoprenaline (receptor-mediated) and forskolin (receptor-independent) were markedly reduced by the presence of a prostanoid TP receptor agonist, U46619; the attenuated relaxations were prevented by acute treatment with S18886, the selective prostanoid TP receptor antagonist, but not by protein kinase C inhibitors. The reduced relaxations were partially restored by IBMX (non-selective PDE inhibitor), cilostazol (PDE3 inhibitor), rolipram (PDE4 inhibitor) or by Y27632 (Rho kinase inhibitor), but not by T0156 (PDE5 inhibitor). U46619 diminished isoprenaline- or forskolin-stimulated rise in cyclic AMP and this effect was inhibited by cilostazol, rolipram or Y27632. The present results suggest that activation of prostanoid TP receptors impairs cyclic AMP-dependent vasorelaxations partly via PDE- and RhoA/Rho kinase-dependent mechanisms. Inhibitors of PDEs and Rho kinase may be useful in the treatment of cardiovascular complications.
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Affiliation(s)
- Cui Qing Liu
- Department of Physiology, Hangzhou Normal University, China
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Eto M. Regulation of cellular protein phosphatase-1 (PP1) by phosphorylation of the CPI-17 family, C-kinase-activated PP1 inhibitors. J Biol Chem 2010; 284:35273-7. [PMID: 19846560 DOI: 10.1074/jbc.r109.059972] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The regulatory circuit controlling cellular protein phosphatase-1 (PP1), an abundant group of Ser/Thr phosphatases, involves phosphorylation of PP1-specific inhibitor proteins. Malfunctions of these inhibitor proteins have been linked to a variety of diseases, including cardiovascular disease and cancer. Upon phosphorylation at Thr(38), the 17-kDa PP1 inhibitor protein, CPI-17, selectively inhibits a specific form of PP1, myosin light chain phosphatase, which transduces multiple kinase signals into the phosphorylation of myosin II and other proteins. Here, the mechanisms underlying PP1 inhibition and the kinase/PP1 cross-talk mediated by CPI-17 and its related proteins, PHI, KEPI, and GBPI, are discussed.
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Affiliation(s)
- Masumi Eto
- Department of Molecular Physiology and Biophysics and Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
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RATTAN SATISH, PHILLIPS BENJAMINR, MAXWELL PINCKNEYJ. RhoA/Rho-kinase: pathophysiologic and therapeutic implications in gastrointestinal smooth muscle tone and relaxation. Gastroenterology 2010; 138:13-8.e1-3. [PMID: 19931260 PMCID: PMC5599165 DOI: 10.1053/j.gastro.2009.11.016] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Affiliation(s)
- SATISH RATTAN
- Department of Medicine, Division of Gastroenterology & Hepatology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA
| | - BENJAMIN R. PHILLIPS
- Department of Surgery, Division of Colon and Rectal Surgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA
| | - PINCKNEY J. MAXWELL
- Department of Surgery, Division of Colon and Rectal Surgery, Jefferson Medical College of Thomas Jefferson University, Philadelphia, PA
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Lartey J, López Bernal A. RHO protein regulation of contraction in the human uterus. Reproduction 2009; 138:407-24. [DOI: 10.1530/rep-09-0160] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The state of contraction in smooth muscle cells of the human uterus is dependent on the interaction of activated forms of actin and myosin. Ras homology (RHO) proteins are small monomeric GTP-binding proteins that regulate actin polymerisation and myosin phosphorylation in smooth muscle cells. Their action is determined by their level of expression, GTP-bound state, intracellular localisation and phosphorylated status. Agonist activated RHO proteins bind to effector kinases such as RHO kinase (ROCK) and diaphanous proteins (DIAPH) to regulate smooth muscle contraction by two mechanisms: ROCK activates smooth muscle myosin either by direct phosphorylation at Ser19/Thr18 or through inhibition of myosin phosphatase which is a trimeric protein regulated by ROCK and by other protein kinases. Actin-polymerising proteins such as DIAPH homolog 1 increase filamentous actin assembly to enhance acto-myosin cross bridge formation and contraction. This review explores recent advances in RHO protein signalling in human myometrium and proposes areas of further research to investigate the involvement of these proteins in the regulation of uterine contractility in pregnancy and labour.
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Qi F, Ogawa K, Tokinaga Y, Uematsu N, Minonishi T, Hatano Y. Volatile anesthetics inhibit angiotensin II-induced vascular contraction by modulating myosin light chain phosphatase inhibiting protein, CPI-17 and regulatory subunit, MYPT1 phosphorylation. Anesth Analg 2009; 109:412-7. [PMID: 19608811 DOI: 10.1213/ane.0b013e3181ac6d96] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Vascular contraction is regulated by myosin light chain (MLC) phosphorylation. Inhibition of MLC phosphatase (MLCP) increases MLC phosphorylation for a given Ca(2+) concentration, and results in promoting myofilament Ca(2+) sensitivity. MLCP activity is mainly determined by protein kinase C (PKC) and Rho kinase through the phosphorylation of both PKC-potentiated inhibitory protein (CPI-17) and myosin phosphatase target subunit (MYPT1). We have previously demonstrated that sevoflurane inhibits PKC phosphorylation and membrane translocation of Rho kinase. This study was designed to investigate the effects of sevoflurane and isoflurane on CPI-17, MYPT1, and MLC phosphorylation in response to angiotensin II (Ang II) in rat aortic smooth muscle. METHODS The effects of sevoflurane or isoflurane (1-3 minimum alveolar concentration) on the vasoconstriction and phosphorylation of MLC, CPI-17, MYPT1 at Thr853 and MYPT1 at Thr696 in response to Ang II were investigated using isometric force transducer and Western blotting, respectively. RESULTS Ang II (10(-7) M) elicited a transient contraction of rat aortic smooth muscle that was inhibited by both sevoflurane and isoflurane in a concentration-dependent manner. Ang II also induced an increase in the phosphorylation of MLC, CPI-17, MYPT1/Thr853 and MYPT1/Thr696. Sevoflurane inhibited the phosphorylation of MLC, CPI-17, and MYPT1/Thr853 in response to Ang II in a concentration-dependent manner. Isoflurane also inhibited MLC phosphorylation in response to Ang II, which was associated with decreases in MYPT1/Thr853, but not in CPI-17. Neither sevoflurane nor isoflurane affected the Ang II-induced phosphorylation of MYPT1/Thr696. CONCLUSION Although both volatile anesthetics inhibited Ang II-induced vasoconstriction and MLC phosphorylation to similar extent, the mechanisms behind the inhibitory effects of each anesthetic on MLCP activity appear to differ.
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Affiliation(s)
- Feng Qi
- Department of Anesthesiology, Wakayama Medical University, Wakayama City 641-0012, Japan
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