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Morris GE, Denniff MJ, Karamanavi E, Andrews SA, Kostogrys RB, Bountziouka V, Ghaderi‐Najafabadi M, Shamkhi N, McConnell G, Kaiser MA, Carleton L, Schofield C, Kessler T, Rainbow RD, Samani NJ, Webb TR. The integrin ligand SVEP1 regulates GPCR-mediated vasoconstriction via integrins α9β1 and α4β1. Br J Pharmacol 2022; 179:4958-4973. [PMID: 35802072 PMCID: PMC9805129 DOI: 10.1111/bph.15921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Revised: 06/10/2022] [Accepted: 06/27/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND AND PURPOSE Vascular tone is regulated by the relative contractile state of vascular smooth muscle cells (VSMCs). Several integrins directly modulate VSMC contraction by regulating calcium influx through L-type voltage-gated Ca2+ channels (VGCCs). Genetic variants in ITGA9, which encodes the α9 subunit of integrin α9β1, and SVEP1, a ligand for integrin α9β1, associate with elevated blood pressure; however, neither SVEP1 nor integrin α9β1 has reported roles in vasoregulation. We determined whether SVEP1 and integrin α9β1 can regulate VSMC contraction. EXPERIMENTAL APPROACH SVEP1 and integrin binding were confirmed by immunoprecipitation and cell binding assays. Human induced pluripotent stem cell-derived VSMCs were used in in vitro [Ca2+ ]i studies, and aortas from a Svep1+/- knockout mouse model were used in wire myography to measure vessel contraction. KEY RESULTS We confirmed the ligation of SVEP1 to integrin α9β1 and additionally found SVEP1 to directly bind to integrin α4β1. Inhibition of SVEP1, integrin α4β1 or α9β1 significantly enhanced [Ca2+ ]i levels in isolated VSMCs to Gαq/11 -vasoconstrictors. This response was confirmed in whole vessels where a greater contraction to U46619 was seen in vessels from Svep1+/- mice compared to littermate controls or when integrin α4β1 or α9β1 was inhibited. Inhibition studies suggested that this effect was mediated via VGCCs, PKC and Rho A/Rho kinase dependent mechanisms. CONCLUSIONS AND IMPLICATIONS Our studies reveal a novel role for SVEP1 and the integrins α4β1 and α9β1 in reducing VSMC contractility. This could provide an explanation for the genetic associations with blood pressure risk at the SVEP1 and ITGA9 loci.
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Affiliation(s)
- Gavin E. Morris
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Matthew J. Denniff
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Elisavet Karamanavi
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Sarah A. Andrews
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Renata B. Kostogrys
- Department of Human Nutrition, Faculty of Food TechnologyUniversity of Agriculture in KrakowKrakowPoland
| | - Vasiliki Bountziouka
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Maryam Ghaderi‐Najafabadi
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Noor Shamkhi
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - George McConnell
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Michael A. Kaiser
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | | | | | - Thorsten Kessler
- Department of Cardiology, German Heart Centre MunichTechnical University of MunichMunichGermany,German Centre of Cardiovascular Research (DZHK e. V.), Partner Site Munich Heart AllianceMunichGermany
| | - Richard D. Rainbow
- Department of Cardiovascular and Metabolic Medicine & Liverpool Centre for Cardiovascular ScienceUniversity of LiverpoolLiverpoolUK
| | - Nilesh J. Samani
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
| | - Thomas R. Webb
- Department of Cardiovascular SciencesUniversity of Leicester and National Institute for Health Research Leicester Biomedical Research Centre, Glenfield HospitalLeicesterUK
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2
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Malacarne PF, Bezzenberger J, Lopez M, Warwick T, Müller N, Brandes RP, Rezende F. Epoxyeicosatrienoic Acid and Prostanoid Crosstalk at the Receptor and Intracellular Signaling Levels to Maintain Vascular Tone. Int J Mol Sci 2022; 23:ijms23115939. [PMID: 35682616 PMCID: PMC9180422 DOI: 10.3390/ijms23115939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/18/2022] [Accepted: 05/23/2022] [Indexed: 11/16/2022] Open
Abstract
Epoxyeicosatrienoic acids (EETs) are signaling lipids produced by the cytochrome P450-(CYP450)-mediated epoxygenation of arachidonic acid. EETs have numerous biological effects on the vascular system, but aspects including their species specificity make their effects on vascular tone controversial. CYP450 enzymes require the 450-reductase (POR) for their activity. We set out to determine the contribution of endothelial CYP450 to murine vascular function using isolated aortic ring preparations from tamoxifen-inducible endothelial cell-specific POR knockout mice (ecPOR-/-). Constrictor responses to phenylephrine were similar between control (CTR) and ecPOR-/- mice. Contrastingly, sensitivity to the thromboxane receptor agonist U46619 and prostaglandin E2 (PGE2) was increased following the deletion of POR. Ex vivo incubation with a non-hydrolyzable EET (14,15-EE-8(Z)-E, EEZE) reversed the increased sensitivity to U46619 to the levels of CTR. EETs had no effect on vascular tone in phenylephrine-preconstricted vessels, but dilated vessels contracted with U46619 or PGE2. As U46619 acts through RhoA-dependent kinase, this system was analyzed. The deletion of POR affected the expression of genes in this pathway and the inhibition of Rho-GTPase with SAR407899 decreased sensitivity to U46619. These data suggest that EET and prostanoid crosstalk at the receptor level and that lack of EET production sensitizes vessels to vasoconstriction via the induction of the Rho kinase system.
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Affiliation(s)
- Pedro Felipe Malacarne
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
| | - Justus Bezzenberger
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
| | - Melina Lopez
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
| | - Timothy Warwick
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
| | - Niklas Müller
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
| | - Ralf P. Brandes
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
| | - Flávia Rezende
- Institute for Cardiovascular Physiology, Goethe-University, 60590 Frankfurt, Germany; (P.F.M.); (J.B.); (M.L.); (T.W.); (N.M.); (R.P.B.)
- German Centre for Cardiovascular Research (DZHK), Partner Site Rhein-Main, 60590 Frankfurt, Germany
- Correspondence: ; Tel.: +49-69-6301-6996; Fax: +49-69-6301-7668
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3
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Lee Y, Zawieja SD, Muthuchamy M. Lymphatic Collecting Vessel: New Perspectives on Mechanisms of Contractile Regulation and Potential Lymphatic Contractile Pathways to Target in Obesity and Metabolic Diseases. Front Pharmacol 2022; 13:848088. [PMID: 35355722 PMCID: PMC8959455 DOI: 10.3389/fphar.2022.848088] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Accepted: 02/17/2022] [Indexed: 01/19/2023] Open
Abstract
Obesity and metabolic syndrome pose a significant risk for developing cardiovascular disease and remain a critical healthcare challenge. Given the lymphatic system's role as a nexus for lipid absorption, immune cell trafficking, interstitial fluid and macromolecule homeostasis maintenance, the impact of obesity and metabolic disease on lymphatic function is a burgeoning field in lymphatic research. Work over the past decade has progressed from the association of an obese phenotype with Prox1 haploinsufficiency and the identification of obesity as a risk factor for lymphedema to consistent findings of lymphatic collecting vessel dysfunction across multiple metabolic disease models and organisms and characterization of obesity-induced lymphedema in the morbidly obese. Critically, recent findings have suggested that restoration of lymphatic function can also ameliorate obesity and insulin resistance, positing lymphatic targeted therapies as relevant pharmacological interventions. There remain, however, significant gaps in our understanding of lymphatic collecting vessel function, particularly the mechanisms that regulate the spontaneous contractile activity required for active lymph propulsion and lymph return in humans. In this article, we will review the current findings on lymphatic architecture and collecting vessel function, including recent advances in the ionic basis of lymphatic muscle contractile activity. We will then discuss lymphatic dysfunction observed with metabolic disruption and potential pathways to target with pharmacological approaches to improve lymphatic collecting vessel function.
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Affiliation(s)
- Yang Lee
- Department of Medical Physiology, College of Medicine, Texas A&M University, Bryan, TX, United States
| | - Scott D Zawieja
- Medical Pharmacology and Physiology, School of Medicine, University of Missouri, Columbia, MO, United States
| | - Mariappan Muthuchamy
- Department of Medical Physiology, College of Medicine, Texas A&M University, Bryan, TX, United States
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4
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Kawarazaki W, Mizuno R, Nishimoto M, Ayuzawa N, Hirohama D, Ueda K, Kawakami-Mori F, Oba S, Marumo T, Fujita T. Salt causes aging-associated hypertension via vascular Wnt5a under Klotho deficiency. J Clin Invest 2021; 130:4152-4166. [PMID: 32597829 DOI: 10.1172/jci134431] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Accepted: 04/24/2020] [Indexed: 12/13/2022] Open
Abstract
Aging is associated with a high prevalence of hypertension due to elevated susceptibility of BP to dietary salt, but its mechanism is unknown. Serum levels of Klotho, an anti-aging factor, decline with age. We found that high salt (HS) increased BP in aged mice and young heterozygous Klotho-knockout mice and was associated with increased vascular expression of Wnt5a and p-MYPT1, which indicate RhoA activity. Not only the Wnt inhibitor LGK974 and the Wnt5a antagonist Box5 but Klotho supplementation inhibits HS-induced BP elevation, similarly to the Rho kinase inhibitor fasudil, associated with reduced p-MYPT1 expression in both groups of mice. In cultured vascular smooth muscle cells, Wnt5a and angiotensin II (Ang II) increased p-MYPT1 expression but knockdown of Wnt5a with siRNA abolished Ang II-induced upregulation of p-MYPT1, indicating that Wnt5a is indispensable for Ang II-induced Rho/ROCK activation. Notably, Klotho inhibited Wnt5a- and Ang II-induced upregulation of p-MYPT1. Consistently, Klotho supplementation ameliorated HS-induced augmentation of reduced renal blood flow (RBF) response to intra-arterial infusion of Ang II and the thromboxane A2 analog U46619, which activated RhoA in both groups of mice and were associated with the inhibition of BP elevation, suggesting that abnormal response of RBF to Ang II contributes to HS-induced BP elevation. Thus, Klotho deficiency underlies aging-associated salt-sensitive hypertension through vascular non-canonical Wnt5a/RhoA activation.
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Affiliation(s)
- Wakako Kawarazaki
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Risuke Mizuno
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan.,Department of Veterinary Pharmacology, Faculty of Veterinary Medicine, Okayama University of Science, Imabari, Ehime, Japan
| | - Mitsuhiro Nishimoto
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Nobuhiro Ayuzawa
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Daigoro Hirohama
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Kohei Ueda
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Fumiko Kawakami-Mori
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Shigeyoshi Oba
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Takeshi Marumo
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan
| | - Toshiro Fujita
- Division of Clinical Epigenetics, Research Center for Advanced Science and Technology, University of Tokyo, Meguro-ku, Tokyo, Japan.,Shinshu University School of Medicine and.,Research Center for Social Systems, Shinshu University, Matsumoto, Nagano, Japan
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5
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Samson SC, Elliott A, Mueller BD, Kim Y, Carney KR, Bergman JP, Blenis J, Mendoza MC. p90 ribosomal S6 kinase (RSK) phosphorylates myosin phosphatase and thereby controls edge dynamics during cell migration. J Biol Chem 2019; 294:10846-10862. [PMID: 31138649 PMCID: PMC6635457 DOI: 10.1074/jbc.ra119.007431] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 05/08/2019] [Indexed: 12/25/2022] Open
Abstract
Cell migration is essential to embryonic development, wound healing, and cancer cell dissemination. Cells move via leading-edge protrusion, substrate adhesion, and retraction of the cell's rear. The molecular mechanisms by which extracellular cues signal to the actomyosin cytoskeleton to control these motility mechanics are poorly understood. The growth factor-responsive and oncogenically activated protein extracellular signal-regulated kinase (ERK) promotes motility by signaling in actin polymerization-mediated edge protrusion. Using a combination of immunoblotting, co-immunoprecipitation, and myosin-binding experiments and cell migration assays, we show here that ERK also signals to the contractile machinery through its substrate, p90 ribosomal S6 kinase (RSK). We probed the signaling and migration dynamics of multiple mammalian cell lines and found that RSK phosphorylates myosin phosphatase–targeting subunit 1 (MYPT1) at Ser-507, which promotes an interaction of Rho kinase (ROCK) with MYPT1 and inhibits myosin targeting. We find that by inhibiting the myosin phosphatase, ERK and RSK promote myosin II–mediated tension for lamella expansion and optimal edge dynamics for cell migration. These findings suggest that ERK activity can coordinately amplify both protrusive and contractile forces for optimal cell motility.
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Affiliation(s)
- Shiela C Samson
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and
| | - Andrew Elliott
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and
| | - Brian D Mueller
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and
| | - Yung Kim
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and
| | - Keith R Carney
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and
| | - Jared P Bergman
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and
| | - John Blenis
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115
| | - Michelle C Mendoza
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah 84112 and; Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115.
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6
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Transcriptional Suppression of CPI-17 Gene Expression in Vascular Smooth Muscle Cells by Tumor Necrosis Factor, Krüppel-Like Factor 4, and Sp1 Is Associated with Lipopolysaccharide-Induced Vascular Hypocontractility, Hypotension, and Mortality. Mol Cell Biol 2019; 39:MCB.00070-19. [PMID: 30936247 PMCID: PMC6517596 DOI: 10.1128/mcb.00070-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 03/22/2019] [Indexed: 12/15/2022] Open
Abstract
Vasodilatory shock in sepsis is caused by the failure of the vasculature to respond to vasopressors, which results in hypotension, multiorgan failure, and ultimately patient death. Recently, it was reported that CPI-17, a key player in the regulation of smooth muscle contraction, was downregulated by lipopolysaccharide (LPS) in mesenteric arteries concordant with vascular hypocontractilty. Vasodilatory shock in sepsis is caused by the failure of the vasculature to respond to vasopressors, which results in hypotension, multiorgan failure, and ultimately patient death. Recently, it was reported that CPI-17, a key player in the regulation of smooth muscle contraction, was downregulated by lipopolysaccharide (LPS) in mesenteric arteries concordant with vascular hypocontractilty. While Sp1 has been shown to activate CPI-17 transcription, it is unknown whether Sp1 is involved in LPS-induced smooth muscle CPI-17 downregulation. Here we report that tumor necrosis factor (TNF) was critical for LPS-induced smooth muscle CPI-17 downregulation. Mechanistically, we identified two GC boxes as a key TNF response element in the CPI-17 promoter and demonstrated that KLF4 was upregulated by TNF, competed with Sp1 for the binding to the GC boxes in the CPI-17 promoter, and repressed CPI-17 transcription through histone deacetylases (HDACs). Moreover, genetic deletion of TNF or pharmacological inhibition of HDACs protected mice from LPS-induced smooth muscle CPI-17 downregulation, vascular hypocontractility, hypotension, and mortality. In summary, these data provide a novel mechanism of the transcriptional control of CPI-17 in vascular smooth muscle cells under inflammatory conditions and suggest a new potential therapeutic strategy for the treatment of vasodilatory shock in sepsis.
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7
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Yan H, Zhang MZ, Wong G, Liu L, Kwok YSS, Kuang SJ, Yang H, Rao F, Li X, Mai LP, Lin QX, Yang M, Zhang QH, Deng CY. Mechanisms of U46619-induced contraction in mouse intrarenal artery. Clin Exp Pharmacol Physiol 2019; 46:643-651. [PMID: 30907443 DOI: 10.1111/1440-1681.13087] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 03/15/2019] [Accepted: 03/19/2019] [Indexed: 11/27/2022]
Abstract
Thromboxane A2 (TXA2 ) has been implicated in the pathogenesis of vascular complications, but the underlying mechanism remains unclear. The contraction of renal arterial rings in mice was measured by a Multi Myograph System. The intracellular calcium concentration ([Ca2+ ]i ) in vascular smooth muscle cells (VSMCs) was obtained by using a fluo-4/AM dye and a confocal laser scanning microscopy. The results show that the U46619-induced vasoconstriction of renal artery was completely blocked by a TXA2 receptor antagonist GR32191, significantly inhibited by a selective phospholipase C (PI-PLC) inhibitor U73122 at 10 μmol/L and partially inhibited by a Phosphatidylcholine - specific phospholipase C (PC-PLC) inhibitor D609 at 50 μmol/L. Moreover, the U46619-induced vasoconstriction was inhibited by a general protein kinase C (PKC) inhibitor chelerythrine at 10 μmol/L, and a selective PKCδ inhibitor rottlerin at 10 μmol/L. In addition, the PKC-induced vasoconstriction was partially inhibited by a Rho-kinase inhibitor Y-27632 at 10 μmol/L and was further completely inhibited together with a putative IP3 receptor antagonist and store-operated Ca2+ (SOC) entry inhibitor 2-APB at 100 μmol/L. On the other hand, U46619-induced vasoconstriction was partially inhibited by L-type calcium channel (Cav1.2) inhibitor nifedipine at 1 μmol/L and 2-APB at 50 and 100 μmol/L. Last, U46619-induced vasoconstriction was partially inhibited by a cell membrane Ca2+ activated C1- channel blocker 5-Nitro-2-(3-phenylpropylamino) benzoic acid (NPPB) at 50 and 100 μmol/L. Our results suggest that the U46619-induced contraction of mouse intrarenal arteries is mediated by Cav1.2 and SOC channel, through the activation of thromboxane-prostanoid receptors and its downstream signaling pathway.
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Affiliation(s)
- Hong Yan
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Meng-Zhen Zhang
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Gordon Wong
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Lin Liu
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Yat Sze Shelia Kwok
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Su-Juan Kuang
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Hui Yang
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Fang Rao
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Xin Li
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Li-Ping Mai
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Qiu-Xiong Lin
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Min Yang
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Qian-Huan Zhang
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
| | - Chun-Yu Deng
- Department of Cardiology, Guangdong Cardiovascular Institute, Guangzhou, China.,Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China.,Guangdong Provincial Key Laboratory of Clinical Pharmacology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, China
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8
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CPI-17-mediated contraction of vascular smooth muscle is essential for the development of hypertension in obese mice. J Genet Genomics 2019; 46:109-118. [PMID: 30948334 DOI: 10.1016/j.jgg.2019.02.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/21/2019] [Accepted: 02/20/2019] [Indexed: 12/14/2022]
Abstract
Several factors have been implicated in obesity-related hypertension, but the genesis of the hypertension is largely unknown. In this study, we found a significantly upregulated expression of CPI-17 (C-kinase-potentiated protein phosphatase 1 inhibitor of 17 kDa) and protein kinase C (PKC) isoforms in the vascular smooth muscles of high-fat diet (HFD)-fed obese mice. The obese wild-type mice showed a significant elevation of blood pressure and enhanced calcium-sensitized contraction of vascular smooth muscles. However, the obese CPI-17-deficient mice showed a normotensive blood pressure, and the calcium-sensitized contraction was consistently reduced. In addition, the mutant muscle displayed an abolished responsive force to a PKC activator and a 30%-50% reduction in both the initial peak force and sustained force in response to various G protein-coupled receptor (GPCR) agonists. Our observations showed that CPI-17-mediated calcium sensitization is mediated through a GPCR/PKC/CPI-17/MLCP/RLC signaling pathway. We therefore propose that the upregulation of CPI-17-mediated calcium-sensitized vasocontraction by obesity contributes to the development of obesity-related hypertension.
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9
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Smoothelin-like 1 deletion enhances myogenic reactivity of mesenteric arteries with alterations in PKC and myosin phosphatase signaling. Sci Rep 2019; 9:481. [PMID: 30679490 PMCID: PMC6346088 DOI: 10.1038/s41598-018-36564-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 11/23/2018] [Indexed: 11/18/2022] Open
Abstract
The role of the smoothelin-like 1 (SMTNL1) protein in mediating vascular smooth muscle contractile responses to intraluminal pressure was examined in resistance vessels. Mesenteric arterioles from wild type (WT) and SMTNL1 global knock-out (KO) mice were examined with pressure myography. SMTNL1 deletion was associated with enhanced myogenic tone in vessels isolated from male, but not female, mice. Intraluminal pressures greater than 40 mmHg generated statistically significant differences in myogenic reactivity between WT and KO vessels. No overt morphological differences were recorded for vessels dissected from KO animals, but SMTNL1 deletion was associated with loss of myosin phosphatase-targeting protein MYPT1 and increase in the myosin phosphatase inhibitor protein CPI-17. Additionally, we observed altered contractile responses of isolated arteries from SMTNL1 KO mice to phenylephrine, KCl-dependent membrane depolarization and phorbol 12,13-dibutyrate (PDBu). Using pharmacological approaches, myogenic responses of both WT and KO vessels were equally affected by Rho-associated kinase (ROCK) inhibition; however, augmented protein kinase C (PKC) signaling was found to contribute to the increased myogenic reactivity of SMTNL1 KO vessels across the 60–120 mmHg pressure range. Based on these findings, we conclude that deletion of SMTNL1 contributes to enhancement of pressure-induced contractility of mesenteric resistance vessels by influencing the activity of myosin phosphatase.
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10
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Liao Q, Yan J, Zhou Z, Luo J, Han Q, Zhang Q, Chen R. Relationship between uterine smooth muscular CPI-17-signal pathway-mediated Ca 2+ sensitivity changes and uterine atony-induced postpartum haemorrhage. J OBSTET GYNAECOL 2018; 39:302-307. [PMID: 30428734 DOI: 10.1080/01443615.2018.1504206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This study aimed to investigate the changes of protein kinase C (PKC)-potentiated phosphatase inhibitor of 17 ku (CPI-17) expression, PKC activity and Rho kinase activity in the maternal uterine smooth muscle (USM), and their roles in the occurrence of uterine atony-induced postpartum haemorrhage (UAI-PPH). Sixty primiparaes who had a caesarean section performed were divided into the case group (with UAI-PPH) and the control group (the uterine contraction was good, without the PPH). The USM-p-CPI-17 (Thr38) protein levels, the activities of PKC and Rho kinase in the case group and the control group were 0.43 ± 0.20, 4.30 ± 0.91, 10.85 ± 1.70 and 0.67 ± 0.32, 0.099 ± 0.028, 0.20 ± 0.071, respectively (p < .05). The down-regulated expression of CPI-17 phosphorylated proteins might be one of the important factors of UAI-PPH, while the activity reduction of PKC and Rho kinase might be the reason that led to the phosphorylation level reduction of USM-CPI-17 in UAI-PPH. Impact Statement What is already known on this subject? The studies have shown that in the late pregnancy period, the total protein and phosphorylated protein of myometrial CPI-17 are significantly higher than in the non-pregnancy state, and they were all involved in regulating and enhancing the Ca2+ sensitivity of USMC during the pregnancy. The data regarding the CPI-17-signal pathway-mediated Ca2+ sensitivity in UAI-PPH is sparse. What do the results of this study add? We have shown that the down-regulated expression of CPI-17 phosphorylated proteins might be one of the important factors of UAI-PPH, while the activity reduction of PKC and Rho kinase might be the reason that led to the phosphorylation level reduction of USM-CPI-17 in UAI-PPH. What are the implications of these findings for clinical practice and/or further research? Further studies are needed to confirm the pathogenesis of CPI-17-signal pathway-mediated Ca2+ sensitivity in UAI-PPH.
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Affiliation(s)
- Qiuping Liao
- a Department of Gynaecology and Obstetrics, Fujian Provincial Maternity and Children's Hospital , Affiliated Hospital of Fujian Medical University , Fuzhou , PR China
| | - Jianying Yan
- a Department of Gynaecology and Obstetrics, Fujian Provincial Maternity and Children's Hospital , Affiliated Hospital of Fujian Medical University , Fuzhou , PR China
| | - Zhimei Zhou
- b Second Affiliated Hospital of Fujian Medical University , Quanzhou , PR China
| | - Jinying Luo
- a Department of Gynaecology and Obstetrics, Fujian Provincial Maternity and Children's Hospital , Affiliated Hospital of Fujian Medical University , Fuzhou , PR China
| | - Qing Han
- a Department of Gynaecology and Obstetrics, Fujian Provincial Maternity and Children's Hospital , Affiliated Hospital of Fujian Medical University , Fuzhou , PR China
| | - Qinjian Zhang
- a Department of Gynaecology and Obstetrics, Fujian Provincial Maternity and Children's Hospital , Affiliated Hospital of Fujian Medical University , Fuzhou , PR China
| | - Rongxin Chen
- a Department of Gynaecology and Obstetrics, Fujian Provincial Maternity and Children's Hospital , Affiliated Hospital of Fujian Medical University , Fuzhou , PR China
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Yang Q, Fujii W, Kaji N, Kakuta S, Kada K, Kuwahara M, Tsubone H, Ozaki H, Hori M. The essential role of phospho‐T38 CPI‐17 in the maintenance of physiological blood pressure using genetically modified mice. FASEB J 2018; 32:2095-2109. [DOI: 10.1096/fj.201700794r] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Qunhui Yang
- Department of Veterinary Pharmacology, Laboratory of Applied Genetics, Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Wataru Fujii
- Laboratory of Applied Genetics, Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Noriyuki Kaji
- Department of Veterinary Pharmacology, Laboratory of Applied Genetics, Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Shigeru Kakuta
- Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Kodai Kada
- Department of Veterinary Pharmacology, Laboratory of Applied Genetics, Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Masayoshi Kuwahara
- Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Hirokazu Tsubone
- Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Hiroshi Ozaki
- Department of Veterinary Pharmacology, Laboratory of Applied Genetics, Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
| | - Masatoshi Hori
- Department of Veterinary Pharmacology, Laboratory of Applied Genetics, Department of Biomedical Science, Department of Veterinary Pathophysiology and Animal Health, and Research Center for Food SafetyGraduate School of Agriculture and Life Sciences, The University of TokyoTokyoJapan
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12
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Characterization of pressure-mediated vascular tone in resistance arteries from bile duct-ligated rats. Oncotarget 2018; 8:30706-30722. [PMID: 28430609 PMCID: PMC5458161 DOI: 10.18632/oncotarget.15409] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 02/01/2017] [Indexed: 12/15/2022] Open
Abstract
In cirrhosis, changes in pressure-mediated vascular tone, a key determinant of systemic vascular resistance (SVR), are unknown. To address this gap in knowledge, we assessed ex vivo dynamics of pressurized mesenteric resistance arteries (diameter ~ 260 μm) from bile duct-ligated (BDL) and sham-operated (SHAM) rats and determined the underlying mechanisms. At isobaric intraluminal pressure (70 mmHg) as well as with step-wise increase in pressure (10-110 mmHg), arteries from SHAM-rats constricted more than BDL-rats, and had reduced luminal area. In both groups, incubation with LNAME (a NOS inhibitor) had no effect on pressure-mediated tone, and expression of NOS isoforms were similar. TEA, which enhances Ca2+ influx, augmented arterial tone only in SHAM-rats, with minimal effect in those from BDL-rats that was associated with reduced expression of Ca2+ channel TRPC6. In permeabilized arteries, high-dose Ca2+ and γGTP enhanced the vascular tone, which remained lower in BDL-rats that was associated with reduced ROCK2 and pMLC expression. Further, compared to SHAM-rats, in BDL-rats, arteries had reduced collagen expression which was associated with increased expression and activity of MMP-9. BDL-rats also had increased plasma reactive oxygen species (ROS). In vascular smooth muscle cells in vitro, peroxynitrite enhanced MMP-9 activity and reduced ROCK2 expression. These data provide evidence that in cirrhosis, pressure-mediated tone is reduced in resistance arteries, and suggest that circulating ROS play a role in reducing Ca2+ sensitivity and enhancing elasticity to induce arterial adaptations. These findings provide insights into mechanisms underlying attenuated SVR in cirrhosis.
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13
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Choo SH, Lee SW, Chae MR, Kang SJ, Sung HH, Han DH, Chun JN, Park JK, Kim CY, Kim HK, So I. Effects of eupatilin on the contractility of corpus cavernosal smooth muscle through nitric oxide-independent pathways. Andrology 2017; 5:1016-1022. [PMID: 28719725 DOI: 10.1111/andr.12397] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 05/26/2017] [Accepted: 06/09/2017] [Indexed: 12/19/2022]
Abstract
Eupatilin (5,7-dihydroxy-3,4,6-trimethoxyflavone) is one of the main compounds present in Artemisia species. Eupatilin has both antioxidative and anti-inflammatory properties and a relaxation effect on vascular contraction regardless of endothelial function. We evaluated the relaxant effects of eupatilin on the corpus cavernosum (CC) of rabbits and the underlying mechanisms of its activity in human corpus cavernosum smooth muscle (CCSM) cells. Isolated rabbit CC strips were mounted in an organ bath system. A conventional whole-cell patch clamp technique was used to measure activation of calcium-sensitive K+ -channel currents in human CCSM cells. The relaxation effect of eupatilin was evaluated by cumulative addition (10-5 m ~ 3 × 10-4 m) to CC strips precontracted with 10-5 m phenylephrine. Western blotting analysis was performed to measure myosin phosphatase targeting subunit 1 (MYPT1) and protein kinase C-potentiated inhibitory protein for heterotrimeric myosin light chain phosphatase of 17-kDa (CPI-17) expression and to evaluate the effect of eupatilin on the RhoA/Rho-kinase pathway. Eupatilin effectively relaxed the phenylephrine-induced tone in the rabbit CC strips in a concentration-dependent manner with an estimated EC50 value of 1.2 ± 1.6 × 10-4 m (n = 8, p < 0.05). Iberiotoxin and tetraethylammonium significantly reduced the relaxation effect (n = 8, p < 0.001 and p = 0.003, respectively). Removal of the endothelium or the presence of L-NAME or indomethacin did not affect the relaxation effect of eupatilin. In CCSM cells, the extracellular application of eupatilin 10-4 m significantly increased the outward currents, and the eupatilin-stimulated currents were significantly attenuated by treatment with 10-7 m iberiotoxin (n = 13, p < 0.05). Eupatilin reduced the phosphorylation level of MYPT1 at Thr853 of MLCP and CPI-17 at Thr38. Eupatilin-induced relaxation of the CCSM cells via NO-independent pathways. The relaxation effects of eupatilin on CCSM cells were partially due to activation of BKCa channels and inhibition of RhoA/Rho-kinase.
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Affiliation(s)
- S H Choo
- Department of Urology, Ajou University School of Medicine, Suwon, Korea
| | - S W Lee
- Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - M R Chae
- Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - S J Kang
- Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - H H Sung
- Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - D H Han
- Department of Urology, Samsung Medical Center, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - J N Chun
- Department of Physiology and Biomedical Sciences, Seoul National University College of Medicine, Seoul, Korea
| | - J K Park
- Department of Urology, Institute for Medical Sciences, Medical School, Chonbuk National University, Research Institute and Clinical Trial Center of Medical Device of Chonbuk National University Hospital, Jeonju, Korea
| | - C Y Kim
- College of Pharmacy and Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan, Korea
| | - H K Kim
- College of Pharmacy, Kyungsung University, Busan, Korea
| | - I So
- Department of Physiology, Seoul National University College of Medicine, Seoul, Korea
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14
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Cooke M, Magimaidas A, Casado-Medrano V, Kazanietz MG. Protein kinase C in cancer: The top five unanswered questions. Mol Carcinog 2017; 56:1531-1542. [PMID: 28112438 DOI: 10.1002/mc.22617] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 01/04/2017] [Accepted: 01/20/2017] [Indexed: 12/29/2022]
Abstract
Few kinases have been studied as extensively as protein kinase C (PKC), particularly in the context of cancer. As major cellular targets for the phorbol ester tumor promoters and diacylglycerol (DAG), a second messenger generated by stimulation of membrane receptors, PKC isozymes play major roles in the control of signaling pathways associated with proliferation, migration, invasion, tumorigenesis, and metastasis. However, despite decades of research, fundamental questions remain to be answered or are the subject of intense controversy. Primary among these unresolved issues are the role of PKC isozymes as either tumor promoter or tumor suppressor kinases and the incomplete understanding on isozyme-specific substrates and effectors. The involvement of PKC isozymes in cancer progression needs to be reassessed in the context of specific oncogenic and tumor suppressing alterations. In addition, there are still major hurdles in addressing isozyme-specific function due to the limited specificity of most pharmacological PKC modulators and the lack of validated predictive biomarkers for response, which impacts the translation of these agents to the clinic. In this review we focus on key controversial issues and upcoming challenges, with the expectation that understanding the intricacies of PKC function will help fulfill the yet unsuccessful promise of targeting PKCs for cancer therapeutics.
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Affiliation(s)
- Mariana Cooke
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Andrew Magimaidas
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Victoria Casado-Medrano
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Marcelo G Kazanietz
- Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
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15
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Kasahara DI, Mathews JA, Ninin FMC, Wurmbrand AP, Liao JK, Shore SA. Role of ROCK2 in CD4 + cells in allergic airways responses in mice. Clin Exp Allergy 2017; 47:224-235. [PMID: 27886408 PMCID: PMC5280456 DOI: 10.1111/cea.12866] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 10/28/2016] [Accepted: 11/20/2016] [Indexed: 12/26/2022]
Abstract
BACKGROUND Rho kinases (ROCKs) contribute to allergic airways disease. ROCKs also play a role in lymphocyte proliferation and migration. OBJECTIVE To determine the role of ROCK2 acting within CD4+ cells in allergic airways responses. METHODS ROCK2-haploinsufficient (ROCK2+/- ) and wild-type mice were sensitized with ovalbumin (OVA). ROCK2+/- mice then received either CD4+ cells from ROCK2-sufficient OVA TCR transgenic (OT-II) mice or saline i.v. 48 h before challenge with aerosolized OVA. Wild-type mice received saline before challenge. Allergic airways responses were measured 48 h after the last challenge. Allergic airways responses were also assessed in mice lacking ROCK2 only in CD4+ cells (ROCK2CD4Cre mice) vs. control (CD4-Cre and ROCK2flox/flox ) mice. RESULTS OVA-induced increases in bronchoalveolar lavage lymphocytes, eosinophils, IL-13, IL-5, and eotaxin were reduced in ROCK2+/- vs. wild-type mice, as were airway hyperresponsiveness and mucous hypersecretion. In ROCK2+/- mice, adoptive transfer with CD4+ cells from OT-II mice restored effects of OVA on lymphocytes, eosinophils, IL-13, IL-5, and mucous hypersecretion to wild-type levels, whereas eotaxin and airway hyperresponsiveness were not affected. ROCK2 inhibitors reduced IL-13-induced release of eotaxin from airway smooth muscle (ASM), similar to effects of these inhibitors on ASM contractility. Despite the ability of adoptive transfer to restore allergic airways inflammation in ROCK2-insufficient mice, allergic inflammation was not different in ROCK2CD4Cre vs. control mice. CONCLUSION ROCK2 contributes to allergic airways responses likely via effects within ASM cells and within non-lymphocyte cells involved in lymphocyte activation and migration into the airways.
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Affiliation(s)
- David I. Kasahara
- Physiology Program, Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02115-6021
| | - Joel A. Mathews
- Physiology Program, Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02115-6021
| | - Fernanda M. C. Ninin
- Physiology Program, Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02115-6021
| | - Allison P. Wurmbrand
- Physiology Program, Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02115-6021
| | - James K. Liao
- Department of Medicine, University of Chicago, Chicago, IL
| | - Stephanie A. Shore
- Physiology Program, Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA 02115-6021
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16
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Xie Z, Su W, Liu S, Zhao G, Esser K, Schroder EA, Lefta M, Stauss HM, Guo Z, Gong MC. Smooth-muscle BMAL1 participates in blood pressure circadian rhythm regulation. J Clin Invest 2015; 125:324-36. [PMID: 25485682 PMCID: PMC4382248 DOI: 10.1172/jci76881] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Accepted: 11/06/2014] [Indexed: 12/22/2022] Open
Abstract
As the central pacemaker, the suprachiasmatic nucleus (SCN) has long been considered the primary regulator of blood pressure circadian rhythm; however, this dogma has been challenged by the discovery that each of the clock genes present in the SCN is also expressed and functions in peripheral tissues. The involvement and contribution of these peripheral clock genes in the circadian rhythm of blood pressure remains uncertain. Here, we demonstrate that selective deletion of the circadian clock transcriptional activator aryl hydrocarbon receptor nuclear translocator-like (Bmal1) from smooth muscle, but not from cardiomyocytes, compromised blood pressure circadian rhythm and decreased blood pressure without affecting SCN-controlled locomotor activity in murine models. In mesenteric arteries, BMAL1 bound to the promoter of and activated the transcription of Rho-kinase 2 (Rock2), and Bmal1 deletion abolished the time-of-day variations in response to agonist-induced vasoconstriction, myosin phosphorylation, and ROCK2 activation. Together, these data indicate that peripheral inputs contribute to the daily control of vasoconstriction and blood pressure and suggest that clock gene expression outside of the SCN should be further evaluated to elucidate pathogenic mechanisms of diseases involving blood pressure circadian rhythm disruption.
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Affiliation(s)
- Zhongwen Xie
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
- Key Laboratory of Tea Biochemistry and Biotechnology, Ministry of Agriculture and Ministry of Education, Anhui Agricultural University, Anhui, China
| | - Wen Su
- Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Shu Liu
- Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Guogang Zhao
- Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Karyn Esser
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Elizabeth A. Schroder
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Mellani Lefta
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Harald M. Stauss
- Department of Health and Human Physiology, The University of Iowa, Iowa City, Iowa, USA
| | - Zhenheng Guo
- Department of Internal Medicine, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Ming Cui Gong
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, Kentucky, USA
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17
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Rho kinase enhances contractions of rat mesenteric collecting lymphatics. PLoS One 2014; 9:e94082. [PMID: 24710574 PMCID: PMC3978029 DOI: 10.1371/journal.pone.0094082] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 03/10/2014] [Indexed: 11/19/2022] Open
Abstract
The mechanisms that control phasic and tonic contractions of lymphatic vessels are poorly understood. We hypothesized that rho kinase ROCK, previously shown to increase calcium (Ca2+) sensitivity in vascular smooth muscle, enhances lymphatic contractile activity in a similar fashion. Contractions of isolated rat mesenteric lymphatic vessels were observed at a luminal pressure of 2 cm H2O in a 37°C bath. The expression of ROCK in isolated rat mesenteric lymphatic vessels was assessed by Western blotting and confocal microscopy. The role of ROCK in contractile function was tested using two specific yet structurally distinct inhibitors: H1152 (0.1–10 μM) and Y-27632 (0.5–50 μM). In addition, lymphatics were transfected with constitutively active (ca)-ROCK protein (2 μg/ml) to assess gain of contractile function. Vessel diameter and the concentration of intracellular free Ca2+ ([Ca2+]i) were simultaneously measured in a subset of isolated lymphatics loaded with the Ca2+-sensing dye fura-2. The results show expression of both the ROCK1 and ROCK2 isoforms in lymphatic vessels. Inhibition of ROCK increased lymphatic end diastolic diameter and end systolic diameter in a concentration-dependent manner. Significant reductions in lymphatic tone and contraction amplitude were observed after treatment 1–10 μM H1152 or 25–50 μM Y-27632. H1152 (10 μM) also significantly reduced contraction frequency. Transient increases in [Ca2+]i preceded each phasic contraction, however this pattern was disrupted by either 10 μM H1152 or 50 μM Y-27632 in the majority of lymphatics studied. The significant decrease in tone caused by H1152 or Y-27632 was not associated with a significant change in the basal [Ca2+]i between transients. Transfection with ca-ROCK protein enhanced lymphatic tone, but was not associated with a significant change in basal [Ca2+]i. Our data suggest that ROCK mediates normal tonic constriction and influences phasic contractions in lymphatics. We propose that ROCK modulates Ca2+ sensitivity of contractile proteins in lymphatics.
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18
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Role of RhoA in Regulating the Pump Function of Isolated Lymphatics From Hemorrhagic Shock Rats. Shock 2013; 40:49-58. [DOI: 10.1097/shk.0b013e31829635cf] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Su W, Xie Z, Liu S, Calderon LE, Guo Z, Gong MC. Smooth muscle-selective CPI-17 expression increases vascular smooth muscle contraction and blood pressure. Am J Physiol Heart Circ Physiol 2013; 305:H104-13. [PMID: 23604714 DOI: 10.1152/ajpheart.00597.2012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Recent data revealed that protein kinase C-potentiated myosin phosphatase inhibitor of 17 kDa (CPI-17), a myosin phosphatase inhibitory protein preferentially expressed in smooth muscle, is upregulated/activated in several diseases but whether this CPI-17 increase plays a causal role in pathologically enhanced vascular smooth muscle contractility and blood pressure remains unclear. To address this possibility, we generated a smooth muscle-specific CPI-17 transgenic mouse model (CPI-17-Tg) and demonstrated that the CPI-17 transgene was selectively expressed in smooth muscle-enriched tissues, including mesenteric arteries. The isometric contractions in the isolated second-order branch of mesenteric artery helical strips from CPI-17-Tg mice were significantly enhanced compared with controls in response to phenylephrine, U-46619, serotonin, ANG II, high potassium, and calcium. The perfusion pressure increases in isolated perfused mesenteric vascular beds in response to norepinephrine were also enhanced in CPI-17-Tg mice. The hypercontractility was associated with increased phosphorylation of CPI-17 and 20-kDa myosin light chain under basal and stimulated conditions. Surprisingly, the protein levels of rho kinase 2 and protein kinase Cα/δ were significantly increased in CPI-17-Tg mouse mesenteric arteries. Radiotelemetry measurements demonstrated that blood pressure was significantly increased in CPI-17-Tg mice. However, no vascular remodeling was detected by morphometric analysis. Taken together, our results demonstrate that increased CPI-17 expression in smooth muscle promotes vascular smooth muscle contractility and increases blood pressure, implicating a pathological significant role of CPI-17 upregulation.
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Affiliation(s)
- Wen Su
- Department of Physiology, University of Kentucky Medical Center, Lexington, KY, USA
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20
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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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21
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Butler T, Paul J, Europe-Finner N, Smith R, Chan EC. Role of serine-threonine phosphoprotein phosphatases in smooth muscle contractility. Am J Physiol Cell Physiol 2013; 304:C485-504. [PMID: 23325405 DOI: 10.1152/ajpcell.00161.2012] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The degree of phosphorylation of myosin light chain 20 (MLC20) is a major determinant of force generation in smooth muscle. Myosin phosphatases (MPs) contain protein phosphatase (PP) 1 as catalytic subunits and are the major enzymes that dephosphorylate MLC20. MP regulatory targeting subunit 1 (MYPT1), the main regulatory subunit of MP in all smooth muscles, is a key convergence point of contractile and relaxatory pathways. Combinations of regulatory mechanisms, including isoform splicing, multiple phosphorylation sites, and scaffolding proteins, modulate MYPT1 activity with tissue and agonist specificities to affect contraction and relaxation. Other members of the PP1 family that do not target myosin, as well as PP2A and PP2B, dephosphorylate a range of proteins that affect smooth muscle contraction. This review discusses the role of phosphatases in smooth muscle contractility with a focus on MYPT1 in uterine smooth muscle. Myometrium shares characteristics of vascular and other visceral smooth muscles yet, during healthy pregnancy, undergoes hypertrophy, hyperplasia, quiescence, and labor as physiological processes. Myometrium presents an accessible model for the study of normal and pathological smooth muscle function, and a better understanding of myometrial physiology may allow the development of novel therapeutics for the many disorders of myometrial physiology from preterm labor to dysmenorrhea.
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Affiliation(s)
- Trent Butler
- Mothers and Babies Research Centre, Faculty of Health, University of Newcastle, Callaghan, NSW 2308, Australia
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22
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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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Liu S, Xie Z, Zhao Q, Pang H, Turk J, Calderon L, Su W, Zhao G, Xu H, Gong MC, Guo Z. Smooth muscle-specific expression of calcium-independent phospholipase A2β (iPLA2β) participates in the initiation and early progression of vascular inflammation and neointima formation. J Biol Chem 2012; 287:24739-53. [PMID: 22637477 DOI: 10.1074/jbc.m112.340216] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Whether group VIA phospholipase A(2) (iPLA(2)β) is involved in vascular inflammation and neointima formation is largely unknown. Here, we report that iPLA(2)β expression increases in the vascular tunica media upon carotid artery ligation and that neointima formation is suppressed by genetic deletion of iPLA(2)β or by inhibiting its activity or expression via perivascular delivery of bromoenol lactone or of antisense oligonucleotides, respectively. To investigate whether smooth muscle-specific iPLA(2)β is involved in neointima formation, we generated transgenic mice in which iPLA(2)β is expressed specifically in smooth muscle cells and demonstrate that smooth muscle-specific expression of iPLA(2)β exacerbates ligation-induced neointima formation and enhanced both production of proinflammatory cytokines and vascular infiltration by macrophages. With cultured vascular smooth muscle cell, angiotensin II, arachidonic acid, and TNF-α markedly induce increased expression of IL-6 and TNF-α mRNAs, all of which were suppressed by inhibiting iPLA(2)β activity or expression with bromoenol lactone, antisense oligonucleotides, and genetic deletion, respectively. Similar suppression also results from genetic deletion of 12/15-lipoxygenase or inhibiting its activity with nordihydroguaiaretic acid or luteolin. Expression of iPLA(2)β protein in cultured vascular smooth muscle cells was found to depend on the phenotypic state and to rise upon incubation with TNF-α. Our studies thus illustrate that smooth muscle cell-specific iPLA(2)β participates in the initiation and early progression of vascular inflammation and neointima formation and suggest that iPLA(2)β may represent a novel therapeutic target for preventing cardiovascular diseases.
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Affiliation(s)
- Shu Liu
- Department of Internal Medicine, University of Kentucky School of Medicine, Lexington, Kentucky 40536, USA
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24
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Abstract
Myometrial smooth muscle contractility is regulated predominantly through the reversible phosphorylation of MYLs (myosin light chains), catalysed by MYLK (MYL kinase) and MYLP (MYL phosphatase) activities. MYLK is activated by Ca2+-calmodulin, and most uterotonic agonists operate through myometrial receptors that increase [Ca2+]i (intracellular Ca2+ concentration). Moreover, there is substantial evidence for Ca2+-independent inhibition of MYLP in smooth muscle, leading to generation of increased MYL phosphorylation and force for a given [Ca2+]i, a phenomenon known as 'Ca2+-sensitization'. ROCK (Rho-associated kinase)-mediated phosphorylation and inhibition of MYLP has been proposed as a mechanism for Ca2+-sensitization in smooth muscle. However, it is unclear to date whether the mechanisms that sensitize the contractile machinery to Ca2+ are important in the myometrium, as they appear to be in vascular and respiratory smooth muscle. In the present paper, we discuss the signalling pathways regulating MYLP activity and the involvement of ROCK in myometrial contractility, and present recent data from our laboratory which support a role for Ca2+-sensitization in human myometrium.
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25
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Two distinct dysfunctions in diabetic mouse mesenteric artery contraction are caused by changes in the Rho A–Rho kinase signaling pathway. Eur J Pharmacol 2012; 683:217-25. [DOI: 10.1016/j.ejphar.2012.03.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 03/07/2012] [Accepted: 03/09/2012] [Indexed: 11/17/2022]
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26
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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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27
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Seok YM, Kim HY, Garmaa O, Cha BY, Woo JT, Kim IK. Effects of magnolol on vascular contraction in rat aortic rings. Clin Exp Pharmacol Physiol 2011; 39:28-36. [DOI: 10.1111/j.1440-1681.2011.05629.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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28
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Hudson CA, Heesom KJ, López Bernal A. Phasic contractions of isolated human myometrium are associated with Rho-kinase (ROCK)-dependent phosphorylation of myosin phosphatase-targeting subunit (MYPT1). Mol Hum Reprod 2011; 18:265-79. [PMID: 22155728 PMCID: PMC3339637 DOI: 10.1093/molehr/gar078] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Force generation in smooth muscle is driven by phosphorylation of myosin light chains (MYL), which is regulated by the equilibrium between the activities of myosin light chain kinase (MYLK) and myosin phosphatase (MYLP). MYLK is activated by Ca2+-calmodulin whereas MYLP is inhibited by phosphorylation of its myosin-binding subunit (MYPT1) by Ca2+-independent mechanisms, leading to generation of increased MYL phosphorylation and force for a given intracellular Ca2+ concentration, a phenomenon known as ‘calcium-sensitization’. The regulation of MYPT1 phosphorylation in human myometrium, which shows increasing phasic contractility at the onset of labour, has yet to be fully investigated. Here, we explore phosphorylation of MYPT1 at Thr696 and Thr853, alongside phosphorylation of MYL, in fresh human myometrial tissue and cultured myometrial cells. We report that pMYPT1 (Thr853) levels are dependent on the activity of Rho-associated kinase (ROCK), determined using the ROCK inhibitor g-H-1152 and siRNA-mediated knockdown of ROCK1/2, and are highly correlated to ppMYL (Thr18/Ser19) levels. Pharmacological inhibition of ROCK was associated with a decrease in oxytocin (OXT)-stimulated contractility of myometrial strips in vitro. Moreover, we have measured pMYPT1 and pMYL levels between and during spontaneous and OXT-stimulated phasic contractions by rapidly freezing contracting muscle, and demonstrate for the first time functional coupling between increases in pMYPT1 (Thr853), ppMYL (Thr18/Ser19) and phasic contractility that is ROCK-dependent. The combined approach of measuring contractility and phosphorylation has demonstrated that the phosphorylation of MYPT1 (Thr853) changes dynamically with each contraction and has elucidated a defined role for ROCK in regulating myometrial contractility through MYLP, providing new insights into uterine physiology which will stimulate further research into treatments for preterm labour.
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Affiliation(s)
- Claire A Hudson
- Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology (Obstetrics and Gynaecology), School of Clinical Sciences, University of Bristol, Bristol BS1 3NY, UK
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29
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Xie Z, Liu D, Liu S, Calderon L, Zhao G, Turk J, Guo Z. Identification of a cAMP-response element in the regulator of G-protein signaling-2 (RGS2) promoter as a key cis-regulatory element for RGS2 transcriptional regulation by angiotensin II in cultured vascular smooth muscles. J Biol Chem 2011; 286:44646-58. [PMID: 22057271 DOI: 10.1074/jbc.m111.265462] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mice deficient in regulator of G-protein signaling-2 (RGS2) have severe hypertension, and RGS2 genetic variations occur in hypertensive humans. A potentially important negative feedback loop in blood pressure homeostasis is that angiotensin II (Ang II) increases vascular smooth muscle cell (VSMC) RGS2 expression. We reported that Group VIA phospholipase A(2) (iPLA(2)β) is required for this response (Xie, Z., Gong, M. C., Su, W., Turk, J., and Guo, Z. (2007) J. Biol. Chem. 282, 25278-25289), but the specific molecular causes and consequences of iPLA(2)β activation are not known. Here we demonstrate that both protein kinases C (PKC) and A (PKA) participate in Ang II-induced VSMC RGS2 mRNA up-regulation, and that actions of PKC and PKA precede and follow iPLA(2)β activation, respectively. Moreover, we identified a conserved cAMP-response element (CRE) in the murine RGS2 promoter that is critical for cAMP-response element-binding protein (CREB) binding and RGS2 promoter activation. Forskolin-stimulated RGS2 mRNA up-regulation is inhibited by CREB sequestration or specific disruption of the CREB-RGS2 promoter interaction, and Ang II-induced CREB phosphorylation and nuclear localization are blocked by iPLA(2)β pharmacologic inhibition or genetic ablation. Ang II-induced intracellular cyclic AMP accumulation precedes CREB phosphorylation and is diminished by inhibiting iPLA(2), cyclooxygenase, or lipoxygenase. Moreover, three single nucleotide polymorphisms identified in hypertensive patients are located in the human RGS2 promoter CREB binding site. Point mutations corresponding to these single nucleotide polymorphisms interfere with stimulation of human RGS2 promoter activity by forskolin. Our studies thus delineate a negative feedback loop to attenuate Ang II signaling in VSMC with potential importance in blood pressure homeostasis and the pathogenesis of human essential hypertension.
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Affiliation(s)
- Zhongwen Xie
- Department of Physiology, University of Kentucky School of Medicine, Lexington, Kentucky 40536, USA
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30
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Kim DH, Seok YM, Kim IK, Lee IK, Jeong SY, Jeoung NH. Glucosamine increases vascular contraction through activation of RhoA/Rho kinase pathway in isolated rat aorta. BMB Rep 2011; 44:415-20. [PMID: 21699756 DOI: 10.5483/bmbrep.2011.44.6.415] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Diabetes is a well-known independent risk factor for vascular disease. However, its underlying mechanism remains unclear. It has been reported that increased influx of the hexosamine biosynthesis pathway (HBP) induces O-GlcNAcylation of proteins, leading to insulin resistance. In this study, we determined whether or not O-GlcNAc modification of proteins could increase vessel contraction. Using an endothelium-denuded aortic ring, we observed that glucosamine induced OGlcNAcylation of proteins and augmented vessel contraction stimulated by U46619, a thromboxane A(2) agonist, via augmentation of the phosphorylation of MLC(20), MYPT1(Thr855), and CPI17, but not phenylephrine. Pretreatment with OGT inhibitor significantly ameliorated glucosamine-induced vessel constriction. Glucosamine treatment also increased RhoA activity, which was also attenuated by OGT inhibitor. In conclusion, glucosamine, a product of glucose influx via the HBP in a diabetic state, increases vascular contraction, at least in part, through activation of the RhoA/Rho kinase pathway, which may be due to O-GlcNAcylation.
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Affiliation(s)
- Do Hyung Kim
- Department of Medical Sciences, Catholic University of Daegu CU Leaders’ College, Gyeongsan 712-702, Korea
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31
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Huang X, Gai Y, Yang N, Lu B, Samuel CS, Thannickal VJ, Zhou Y. Relaxin regulates myofibroblast contractility and protects against lung fibrosis. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:2751-65. [PMID: 21983071 DOI: 10.1016/j.ajpath.2011.08.018] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 07/18/2011] [Accepted: 08/22/2011] [Indexed: 12/11/2022]
Abstract
Myofibroblasts are specialized contractile cells that participate in tissue fibrosis and remodeling, including idiopathic pulmonary fibrosis (IPF). Mechanotransduction, a process by which mechanical stimuli are converted into biochemical signals, regulates myofibroblast differentiation. Relaxin is a peptide hormone that mediates antifibrotic effects through regulation of collagen synthesis and turnover. In this study, we demonstrate enhanced myofibroblast contraction in bleomycin-induced lung fibrosis in mice and in fibroblastic foci of human subjects with IPF, using phosphorylation of the regulatory myosin light chain (MLC(20)) as a biomarker of in vivo cellular contractility. Compared with wild-type mice, relaxin knockout mice express higher lung levels of phospho-MLC(20) and develop more severe bleomycin-induced lung fibrosis. Exogenous relaxin inhibits MLC(20) phosphorylation and bleomycin-induced lung fibrosis in both relaxin knockout and wild-type mice. Ex vivo studies of IPF lung myofibroblasts demonstrate decreases in MLC(20) phosphorylation and reduced contractility in response to relaxin. Characterization of the signaling pathway reveals that relaxin regulates MLC(20) dephosphorylation and lung myofibroblast contraction by inactivating RhoA/Rho-associated protein kinase through a nitric oxide/cGMP/protein kinase G-dependent mechanism. These studies identify a novel antifibrotic role of relaxin involving the inhibition of the contractile phenotype of lung myofibroblasts and suggest that targeting myofibroblast contractility with relaxin-like peptides may be of therapeutic benefit in the treatment of fibrotic lung disease.
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Affiliation(s)
- Xiangwei Huang
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
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32
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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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33
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Seok YM, Choi YW, Kim GD, Kim HY, Takuwa Y, Kim IK. Effects of gomisin A on vascular contraction in rat aortic rings. Naunyn Schmiedebergs Arch Pharmacol 2010; 383:45-56. [DOI: 10.1007/s00210-010-0571-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 09/08/2010] [Indexed: 01/06/2023]
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34
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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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35
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Xie Z, Gong MC, Su W, Xie D, Turk J, Guo Z. Role of calcium-independent phospholipase A2beta in high glucose-induced activation of RhoA, Rho kinase, and CPI-17 in cultured vascular smooth muscle cells and vascular smooth muscle hypercontractility in diabetic animals. J Biol Chem 2010; 285:8628-38. [PMID: 20086008 DOI: 10.1074/jbc.m109.057711] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Previous studies suggest that high glucose-induced RhoA/Rho kinase/CPI-17 activation is involved in diabetes-associated vascular smooth muscle hypercontractility. However, the upstream signaling that links high glucose and RhoA/Rho kinase/CPI-17 activation is unknown. Here we report that calcium-independent phospholipase A(2)beta (iPLA(2)beta) is required for high glucose-induced RhoA/Rho kinase/CPI-17 activation and thereby contributes to diabetes-associated vascular smooth muscle hypercontractility. We demonstrate that high glucose increases iPLA(2)beta mRNA, protein, and iPLA(2) activity in a time-dependent manner. Protein kinase C is involved in high glucose-induced iPLA(2)beta protein up-regulation. Inhibiting iPLA(2)beta activity with bromoenol lactone or preventing its expression by genetic deletion abolishes high glucose-induced RhoA/Rho kinase/CPI-17 activation, and restoring expression of iPLA(2)beta in iPLA(2)beta-deficient cells also restores high glucose-induced CPI-17 phosphorylation. Pharmacological and genetic inhibition of 12/15-lipoxygenases has effects on high glucose-induced CPI-17 phosphorylation similar to iPLA(2)beta inhibition. Moreover, increases in iPLA(2) activity and iPLA(2)beta protein expression are also observed in both type 1 and type 2 diabetic vasculature. Pharmacological and genetic inhibition of iPLA(2)beta, but not iPLA(2)gamma, diminishes diabetes-associated vascular smooth muscle hypercontractility. In summary, our results reveal a novel mechanism by which high glucose-induced, protein kinase C-mediated iPLA(2)beta up-regulation activates the RhoA/Rho kinase/CPI-17 via 12/15-lipoxygenases and thereby contributes to diabetes-associated vascular smooth muscle hypercontractility.
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Affiliation(s)
- Zhongwen Xie
- Department of Physiology, University of Kentucky School of Medicine, Lexington, Kentucky 40536, USA
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36
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Baek I, Jeon SB, Song MJ, Yang E, Sohn UD, Kim IK. Flavone Attenuates Vascular Contractions by Inhibiting RhoA/Rho Kinase Pathway. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2009; 13:201-7. [PMID: 19885038 DOI: 10.4196/kjpp.2009.13.3.201] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 05/27/2009] [Accepted: 06/19/2009] [Indexed: 11/15/2022]
Abstract
Our previous study demonstrated that flavone inhibits vascular contractions by decreasing the phosphorylation levelof the myosin phosphatase target subunit (MYPT1). In the present study, we hypothesized that flavone attenuates vascular contractions through the inhibition of the RhoA/Rho kinase pathway. Rat aortic rings were denuded of endothelium, mounted in organ baths, and contracted with either 30 nM U46619 (a thromboxane A2 analogue) or 8.0 mM NaF 30 min after pretreatment with either flavone (100 or 300 microM) or vehicle. We determined the phosphorylation level of the myosin light chain (MLC(20)), the myosin phophatase targeting subunit 1 (MYPT1) and the protein kinase C-potentiated inhibitory protein for heterotrimeric myosin light chain phophatase of 17-kDa (CPI17) by means of Western blot analysis. Flavone inhibited, not only vascular contractions induced by these contractors, but also the levels of MLC(20) phosphorylation. Furthermore, flavone inhibited the activation of RhoA which had been induced by either U46619 or NaF. Incubation with flavone attenuated U46619-or NaF-induced phosphorylation of MYPT1(Thr855) and CPI17(Thr38), the downstream effectors of Rho-kinase. In regards to the Ca(2+)-free solution, flavone inhibited the phosphorylation of MYPT1(Thr855) and CPI17(Thr38), as well as vascular contractions induced by U46619. These results indicate that flavone attenuates vascular contractions, at least in part, through the inhibition of the RhoA/Rho-kinase pathway.
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Affiliation(s)
- Inji Baek
- Department of Pharmacology, Kyungpook National University School of Medicine, Daegu 700-422, Korea
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37
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Yang E, Jeon SB, Baek I, Chen ZA, Jin Z, Kim IK. 17beta-estradiol attenuates vascular contraction through inhibition of RhoA/Rho kinase pathway. Naunyn Schmiedebergs Arch Pharmacol 2009; 380:35-44. [PMID: 19296091 DOI: 10.1007/s00210-009-0408-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 02/22/2009] [Indexed: 01/11/2023]
Abstract
We hypothesized that 17beta-estradiol attenuates vascular contraction through inhibition of RhoA/Rho kinase pathway. Rat aortic rings were contracted with cumulative addition of U46619, NaF, KCl or PDBu 30 min after pretreatment with 17beta-estradiol (10, 30, and 100 microM) or vehicle. We measured the amount of GTP RhoA and 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 17 kDa (CPI17). Pretreatment with 17beta-estradiol dose-dependently inhibited the concentration-response curves in response to U46619, NaF or KCl, but not to PDBu. 17beta-Estradiol decreased not only the level of phosphorylation of MYPT1(Thr855) and CPI17(Thr38) as well as MLC(20), but also the activity of RhoA induced by U46619 or NaF. However, 17beta-estradiol did not affect the level of phosphorylation of CPI17 induced by PDBu. 17beta-Estradiol attenuates vascular contraction through inhibition of RhoA/Rho kinase pathway.
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Affiliation(s)
- Enyue Yang
- Department of Pharmacology, Kyungpook National University School of Medicine, 101 Dongin-2-Ga, Daegu 700-422, Republic of Korea
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38
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Ratz PH, Miner AS. Role of protein kinase Czeta and calcium entry in KCl-induced vascular smooth muscle calcium sensitization and feedback control of cellular calcium levels. J Pharmacol Exp Ther 2008; 328:399-408. [PMID: 19011165 DOI: 10.1124/jpet.108.142422] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The degree of tonic force (F) maintenance induced in vascular smooth muscle upon K(+) depolarization with 110 mM KCl can be greatly reduced by inhibition of rhoA kinase (ROCK). We explored the possibility that a protein kinase C (PKC) isotype may also play a role in causing KCl-induced Ca(2+) sensitization. In isometric rings of rabbit artery, the PKC inhibitors, Go-6983 (3-[1-[3-(dimethylamino)propyl]-5-methoxy-1H-indol-3-yl]-4-(1H-indol-3-yl)-1H-pyrrole-2,5-dione), GF-109203X (2-[1-(3-dimethylaminopropyl)indol-3-yl]-3-(indol-3-yl) maleimide), and a cell-permeable (myristoylated) pseudosubstrate inhibitor of PKCzeta (PI(PKCzeta)) inhibited KCl-induced tonic F. A myristoylated pseudosubstrate inhibitor of PKCalpha/beta that inhibited phorbol dibutyrate-induced F slightly potentiated KCl-induced tonic F and attenuated 30 mM KCl-induced F. Although the ROCK inhibitor, H-1152 [(S)-(+)-2-methyl-1-[(4-methyl-5-isoquinolinyl)-sulfonyl]-hexahydro-1H-1,4-diazepine dihydrochloride], reduced basal phosphorylation of myosin light-chain phosphatase-targeting subunit at Thr853 (MYPT1-pT853), 3 and 10 muM GF-109203X inhibited only KCl-stimulated phosphorylation, not basal MYPT1-pT853. In fura-2-loaded tissues, GF-109203X and PI(PKCzeta) elevated basal [Ca(2+)](i) (calcium) and potentiated KCl-induced tonic increases in calcium while reducing KCl-induced tonic increases in F. Blockade by nifedipine of Ca(2+) entry through voltage-operated Ca(2+) channels reduced KCl-induced Ca(2+) sensitization and KCl-stimulated but not basal MYPT1-pT853. These data together support a model in which ROCK and PKCzeta are constitutively active and function in "resting" muscle to regulate the basal levels of MYPT1-pT853 and calcium, respectively. In this model, KCl-induced increases in calcium activate PKCzeta to feed forward and cause additional MYPT1-pT853 above that induced by constitutive ROCK, permitting Ca(2+) sensitization and strong F maintenance. Active PKCzeta also feeds back to attenuate the degree of KCl-induced increases in calcium.
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Affiliation(s)
- Paul H Ratz
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, School of Medicine, PO Box 980614, 1101 East Marshall Street, Richmond, VA 23298-0614, USA.
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39
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Seok YM, Baek I, Kim YH, Jeong YS, Lee IJ, Shin DH, Hwang YH, Kim IK. Isoflavone attenuates vascular contraction through inhibition of the RhoA/Rho-kinase signaling pathway. J Pharmacol Exp Ther 2008; 326:991-8. [PMID: 18577703 DOI: 10.1124/jpet.108.138529] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Isoflavones decrease blood pressure, improve lipid profiles, and restore vascular function. We hypothesized that isoflavone attenuates vascular contraction by inhibiting RhoA/Rho-kinase signaling pathway. Rat aortic rings were denuded of endothelium, mounted in organ baths, and contracted with 11,9 epoxymethano-prostaglandin F(2alpha) (U46619), a thromboxane A2 analog, or KCl 30 min after the pretreatment with genistein (4',5,7-trihydroxyisoflavone), daidzein (4',7-dihydroxyisoflavone), or vehicle. We determined the phosphorylation level of the myosin light chain (MLC(20)), myosin phosphatase-targeting subunit 1 (MYPT1), and protein kinase C-potentiated inhibitory protein for heterotrimeric myosin light-chain phosphatase of 17 kDa (CPI17) by means of the Western blot. We also measured the amount of GTP RhoA as a marker regarding RhoA activation. The cumulative additions of U46619 or KCl increased vascular tension in a concentration-dependent manner, which were inhibited by pretreatment with genistein or daidzein. Both U46619 (30 nM) and KCl (50 mM) increased MLC(20) phosphorylation levels, which were inhibited by genistein and daidzein. Furthermore, both genistein and daidzein decreased the amount of GTP RhoA activated by either U46619 or KCl. U46619 (30 nM) increased phosphorylation of the MYPT1(Thr855) and CPI17(Thr38), which were also inhibited by genistein or daidzein. However, neither genistein nor daidzein inhibited phorbol 12,13-dibutyrate-induced vascular contraction and CPI17 phosphorylation. In conclusion, isoflavone attenuates vascular contraction, at least in part, through inhibition of the RhoA/Rho-kinase signaling pathway.
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Affiliation(s)
- Young Mi Seok
- Department of Pharmacology, Kyungpook National University School of Medicine, Daegu 700-422, Republic of Korea
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Tas PWL, Gambaryan S, Roewer N. Volatile anesthetics affect the morphology of rat glioma C6 cells via RhoA, ERK, and Akt activation. J Cell Biochem 2008; 102:368-76. [PMID: 17492663 DOI: 10.1002/jcb.21294] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Treatment of rat glioma C6 cells with the beta-receptor agonist isoproterenol induces a massive increase in cAMP. Concomitantly the cells change their morphology from a fibroblast-type to an astrocyte-like (stellated) cell shape. The stellated morphology can be completely reverted by thrombin and sphingosine-1-phosphate (S-1-P) but also to a certain extent by clinical concentrations of volatile anesthetics. The anesthetic-induced reversion of the stellated cell shape seems to be mediated by a number of cellular alterations. Central to the effect is most likely a RhoA/Rho-kinase activation, but also the MAPKK/MEK and the Akt/protein kinase B pathway are activated by the anesthetics. With the use of specific inhibitors we were able to show that activation of the MAPKK/MEK pathway inhibits, whereas activation of the Akt/protein kinase B pathway stimulates the reversal of the stellated cell shape by the anesthetics. In summary, volatile anesthetics affect the morphology of rat glioma C6 cells by activation of the RhoA/Rho kinase, the MAPKK/MEK, and the Akt/protein kinase B signaling pathways.
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Affiliation(s)
- Piet W L Tas
- Department of Anaesthesiology, University of Würzburg, Center of Operative Medicine, Würzburg, Germany.
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41
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Eto M, Kitazawa T, Matsuzawa F, Aikawa SI, Kirkbride JA, Isozumi N, Nishimura Y, Brautigan DL, Ohki SY. Phosphorylation-induced conformational switching of CPI-17 produces a potent myosin phosphatase inhibitor. Structure 2007; 15:1591-602. [PMID: 18073109 PMCID: PMC2217667 DOI: 10.1016/j.str.2007.10.014] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Revised: 10/02/2007] [Accepted: 10/03/2007] [Indexed: 11/17/2022]
Abstract
Phosphorylation of endogenous inhibitor proteins for type-1 Ser/Thr phosphatase (PP1) provides a mechanism for reciprocal coordination of kinase and phosphatase activities. A myosin phosphatase inhibitor protein CPI-17 is phosphorylated at Thr38 through G-protein-mediated signals, resulting in a >1000-fold increase in inhibitory potency. We show here the solution NMR structure of phospho-T38-CPI-17 with rmsd of 0.36 +/- 0.06 A for the backbone secondary structure, which reveals how phosphorylation triggers a conformational change and exposes an inhibitory surface. This active conformation is stabilized by the formation of a hydrophobic core of intercalated side chains, which is not formed in a phospho-mimetic D38 form of CPI-17. Thus, the profound increase in potency of CPI-17 arises from phosphorylation, conformational change, and hydrophobic stabilization of a rigid structure that poses the phosphorylated residue on the protein surface and restricts its hydrolysis by myosin phosphatase. Our results provide structural insights into transduction of kinase signals by PP1 inhibitor proteins.
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Affiliation(s)
- Masumi Eto
- Department of Molecular Physiology and Biophysics, Thomas Jefferson University, 1020 Locust Street, Philadelphia, Pennsylvania 19107, USA
| | - Toshio Kitazawa
- Boston Biomedical Research Institute, 64 Grove Street, Watertown, Massachusetts, USA
| | - Fumiko Matsuzawa
- Dept Clinical Genetics, Tokyo Metropolitan Institute of Medical Science, Honkomagome 3-18-22, Bunkyo-ku, Tokyo 113-8613, Japan
| | - Sei-ichi Aikawa
- Dept Clinical Genetics, Tokyo Metropolitan Institute of Medical Science, Honkomagome 3-18-22, Bunkyo-ku, Tokyo 113-8613, Japan
| | - Jason A. Kirkbride
- Department of Molecular Physiology and Biophysics, Thomas Jefferson University, 1020 Locust Street, Philadelphia, Pennsylvania 19107, USA
| | - Noriyoshi Isozumi
- Center for Nano Materials and Technology (CNMT), Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Tatsunokuchi, Ishikawa, 923-1292, Japan
| | - Yumi Nishimura
- Center for Nano Materials and Technology (CNMT), Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Tatsunokuchi, Ishikawa, 923-1292, Japan
| | - David L. Brautigan
- Center for Cell Signaling, University of Virginia School of Medicine, 1400 Jefferson Park Avenue, Charlottesville, Virginia 22908, USA
| | - Shin-ya Ohki
- Center for Nano Materials and Technology (CNMT), Japan Advanced Institute of Science and Technology (JAIST), 1-1 Asahidai, Tatsunokuchi, Ishikawa, 923-1292, Japan
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42
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Nuno DW, Korovkina VP, England SK, Lamping KG. RhoA Activation Contributes to Sex Differences in Vascular Contractions. Arterioscler Thromb Vasc Biol 2007; 27:1934-40. [PMID: 17556652 DOI: 10.1161/atvbaha.107.144675] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective—
Studies have suggested that sex differences in endothelial function in part account for the lower incidence of cardiovascular disease in premenopausal women compared with men. Less is known about the role of smooth muscle. We hypothesized that signaling mechanisms that regulate calcium sensitivity in vascular muscle also play a role in determining sex differences in contractile function.
Methods and Results—
In aorta, concentration-dependent contractions to serotonin were greater in male versus female mice whereas contractions to KCl and U46619 were similar. Nitric oxide or other endothelial-derived factors did not account for the difference in responses to serotonin because inhibition of nitric oxide synthase (NOS) with N
G
-nitro-
l
-arginine, genetic deficiency of endothelial NOS, and removal of endothelium increased contractions but did not abolish the enhanced contractions in aorta from males. Contractions in aorta from both males and females were abolished by a serotonergic 5HT
2A
receptor antagonist (ketanserin), however there was no sex difference in 5HT
2A
receptor expression. Activation of RhoA and Rho-kinase by serotonin was greater in aorta from males compared with females, but this was not related to greater expression of RhoA or Rho-kinase isoforms (ROCK1 and ROCK2). The sex difference in aortic contractions to serotonin was abolished by an inhibitor of Rho-kinase, Y27632.
Conclusion—
We conclude that increased contractions to serotonin in aorta from male mice are attributable to differences in RhoA/Rho-kinase activation in smooth muscle independent of differences in the expression of RhoA or Rho-kinase.
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Affiliation(s)
- Daniel W Nuno
- VA Medical Center, 10W16, 601 Highway 6 West, Iowa City, IA 52246, USA
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43
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Xie Z, Gong MC, Su W, Turk J, Guo Z. Group VIA phospholipase A2 (iPLA2beta) participates in angiotensin II-induced transcriptional up-regulation of regulator of g-protein signaling-2 in vascular smooth muscle cells. J Biol Chem 2007; 282:25278-89. [PMID: 17613534 PMCID: PMC2096773 DOI: 10.1074/jbc.m611206200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Rgs2 (regulator of G-protein signaling-2)-deficient mice exhibit severe hypertension, and genetic variations of RGS2 occur in hypertensive patients. RGS2 mRNA up-regulation by angiotensin II (Ang II) in vascular smooth muscle cells (VSMC) is a potentially important negative feedback mechanism in blood pressure homeostasis, but how it occurs is unknown. Here we demonstrate that group VIA phospholipase A2 (iPLA2beta) plays a pivotal role in Ang II-induced RGS2 mRNA up-regulation in VSMC by three independent approaches, including pharmacologic inhibition with a bromoenol lactone suicide substrate, suppression of iPLA2beta expression with antisense oligonucleotides, and genetic deletion in iPLA2beta-null mice. Selective inhibition of iPLA2beta by each of these approaches abolishes Ang II-induced RGS2 mRNA up-regulation. Furthermore, using adenovirus-mediated gene transfer, we demonstrate that restoration of iPLA2beta-expression in iPLA2beta-null VSMC reconstitutes the ability of Ang II to up-regulate RGS2 mRNA expression. In contrast, Ang II-induced vasodilator-stimulated phosphoprotein phosphorylation and Ang II receptor expression are unaffected. Moreover, in wild-type but not iPLA2beta-null VSMC, Ang II stimulates iPLA2 enzymatic activity significantly. Both arachidonic acid and lysophosphatidylcholine, products of iPLA2beta action, induce RGS2 mRNA up-regulation. Inhibition of lipoxygenases, particularly 15-lipoxygenase, and cyclooxygenases, but not cytochrome P450-dependent epoxygenases inhibits Ang II- or AA-induced RGS2 mRNA expression. Moreover, RGS2 protein expression is also up-regulated by Ang II, and this is attenuated by bromoenol lactone. Disruption of the Ang II/iPLA2beta/RGS2 feedback pathway in iPLA2beta-null cells potentiates Ang II-induced vasodilator-stimulated phosphoprotein and Akt phosphorylation in a time-dependent manner. Collectively, our results demonstrate that iPLA2beta participates in Ang II-induced transcriptional up-regulation of RGS2 in VSMC.
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MESH Headings
- Adenoviridae
- Angiotensin II/pharmacology
- Animals
- Arachidonic Acid/pharmacology
- Blood Pressure/drug effects
- Blood Pressure/physiology
- Cell Adhesion Molecules/metabolism
- Enzyme Activation/drug effects
- Enzyme Activation/physiology
- Gene Deletion
- Gene Expression Regulation, Enzymologic/drug effects
- Gene Expression Regulation, Enzymologic/physiology
- Group VI Phospholipases A2
- Homeostasis/drug effects
- Homeostasis/physiology
- Lysophosphatidylcholines/pharmacology
- Mice
- Mice, Knockout
- Microfilament Proteins/metabolism
- Muscle, Smooth, Vascular/enzymology
- Myocytes, Smooth Muscle/enzymology
- Naphthalenes/pharmacology
- Oligodeoxyribonucleotides, Antisense/pharmacology
- Oxidoreductases/antagonists & inhibitors
- Oxidoreductases/metabolism
- Phospholipases A/antagonists & inhibitors
- Phospholipases A/deficiency
- Phospholipases A/metabolism
- Phospholipases A2
- Phosphoproteins/metabolism
- Phosphorylation/drug effects
- Proto-Oncogene Proteins c-akt/metabolism
- Pyrones/pharmacology
- RGS Proteins/antagonists & inhibitors
- RGS Proteins/deficiency
- RGS Proteins/metabolism
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Rats
- Rats, Sprague-Dawley
- Signal Transduction/drug effects
- Signal Transduction/physiology
- Time Factors
- Transcription, Genetic/drug effects
- Transcription, Genetic/physiology
- Transduction, Genetic
- Up-Regulation/drug effects
- Up-Regulation/physiology
- Vasoconstrictor Agents/pharmacology
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Affiliation(s)
- Zhongwen Xie
- Department of Physiology and the Graduate Center for Nutritional Sciences, University of Kentucky, Lexington, Kentucky 40536, USA
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44
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Patel CA, Rattan S. RhoA Prenylation Inhibitor Produces Relaxation of Tonic Smooth Muscle of Internal Anal Sphincter. J Pharmacol Exp Ther 2007; 321:501-8. [PMID: 17322025 DOI: 10.1124/jpet.107.119339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RhoA prenylation is a critical step for the translocation of RhoA to the membrane and its activation in response to agonist-induced sustained contraction of the smooth muscle. However, the effect and role of RhoA prenylation in the spontaneously tonic smooth muscle, such as internal anal sphincter (IAS), is not known. Present studies determined RhoA prenylation and its association with the basal tone in the IAS before and after the RhoA prenylation inhibitor, geranylgeranyl transferase inhibitor GGTI-297 [N-4-[2(R)-amino-3-mercaptopropyl]amino-2-naphthylbenzoyl-(L)-leucine,TFA]. Western blot analyses of cytosolic and membrane fractions determined the effects of RhoA prenylation inhibition on the cellular distribution of the RhoA. Additional studies were performed to determine the relationship between RhoA prenylation and Rho kinase (ROCK) activity. GGTI-297 decreased prenylation of RhoA, decreased ROCK activity, and caused a corresponding fall in the IAS tone. These inhibitory effects following RhoA prenylation blockade were demonstrated to be directly on the spontaneously contracted IAS smooth muscle cells. Western blot analysis revealed high levels of RhoA in the IAS smooth muscle cellular membrane in the basal state, and GGTI-297 shifted the RhoA localization to the cytosol. RhoA prenylation may play an important role in the translocation of RhoA to the smooth muscle cell membrane leading to its activation and for the maintenance of basal tone in the IAS.
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Affiliation(s)
- Chirag A Patel
- Department of Medicine, Division of Gastroenterology and Hepatology, Jefferson Medical College, Thomas Jefferson University, 1025 Walnut Street, Philadelphia, PA 19107, USA
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45
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46
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Maeda A, Ozaki YI, Sivakumaran S, Akiyama T, Urakubo H, Usami A, Sato M, Kaibuchi K, Kuroda S. Ca2+ -independent phospholipase A2-dependent sustained Rho-kinase activation exhibits all-or-none response. Genes Cells 2006; 11:1071-83. [PMID: 16923126 DOI: 10.1111/j.1365-2443.2006.01001.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Sustained contraction of cells depends on sustained Rho-associated kinase (Rho-kinase) activation. We developed a computational model of the Rho-kinase pathway to understand the systems characteristics. Thrombin-dependent in vivo transient responses of Rho activation and Ca2+ increase could be reproduced in silico. Low and high thrombin stimulation induced transient and sustained phosphorylation, respectively, of myosin light chain (MLC) and myosin phosphatase targeting subunit 1 (MYPT1) in vivo. The transient phosphorylation of MLC and MYPT1 could be reproduced in silico, but their sustained phosphorylation could not. This discrepancy between in vivo and in silico in the sustained responses downstream of Rho-kinase indicates that a missing pathway(s) may be responsible for the sustained Rho-kinase activation. We found, experimentally, that the sustained phosphorylation of MLC and MYPT1 exhibit all-or-none responses. Bromoenol lactone, a specific inhibitor of Ca2+ -independent phospholipase A2 (iPLA2), inhibited sustained phosphorylation of MLC and MYPT1, which indicates that sustained Rho-kinase activation requires iPLA2 activity. Thus, the systems analysis of the Rho-kinase pathway identified a novel iPLA2-dependent mechanism of the sustained Rho-kinase activation, which exhibits an all-or-none response.
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Affiliation(s)
- Akio Maeda
- Undergraduate Program for Bioinformatics and Systems Biology, Graduate School of Information Science and Technology, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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47
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Dimopoulos GJ, Semba S, Kitazawa K, Eto M, Kitazawa T. Ca2+-dependent rapid Ca2+ sensitization of contraction in arterial smooth muscle. Circ Res 2006; 100:121-9. [PMID: 17158339 PMCID: PMC2212616 DOI: 10.1161/01.res.0000253902.90489.df] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ca(2+) ion is a universal intracellular messenger that regulates numerous biological functions. In smooth muscle, Ca(2+) with calmodulin activates myosin light chain (MLC) kinase to initiate a rapid MLC phosphorylation and contraction. To test the hypothesis that regulation of MLC phosphatase is involved in the rapid development of MLC phosphorylation and contraction during Ca(2+) transient, we compared Ca(2+) signal, MLC phosphorylation, and 2 modes of inhibition of MLC phosphatase, phosphorylation of CPI-17 Thr38 and MYPT1 Thr853, during alpha(1) agonist-induced contraction with/without various inhibitors in intact rabbit femoral artery. Phenylephrine rapidly induced CPI-17 phosphorylation from a negligible amount to a peak value of 0.38+/-0.04 mol of Pi/mol within 7 seconds following stimulation, similar to the rapid time course of Ca(2+) rise and MLC phosphorylation. This rapid CPI-17 phosphorylation was dramatically inhibited by either blocking Ca(2+) release from the sarcoplasmic reticulum or by pretreatment with protein kinase C inhibitors, suggesting an involvement of Ca(2+)-dependent protein kinase C. This was followed by a slow Ca(2+)-independent and Rho-kinase/protein kinase C-dependent phosphorylation of CPI-17. In contrast, MYPT1 phosphorylation had only a slow component that increased from 0.29+/-0.09 at rest to the peak of 0.68+/-0.14 mol of Pi/mol at 1 minute, similar to the time course of contraction. Thus, there are 2 components of the Ca(2+) sensitization through inhibition of MLC phosphatase. Our results support the hypothesis that the initial rapid Ca(2+) rise induces a rapid inhibition of MLC phosphatase coincident with the Ca(2+)-induced MLC kinase activation to synergistically initiate a rapid MLC phosphorylation and contraction in arteries with abundant CPI-17 content.
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48
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El-Toukhy A, Given AM, Ogut O, Brozovich FV. PHI-1 interacts with the catalytic subunit of myosin light chain phosphatase to produce a Ca(2+) independent increase in MLC(20) phosphorylation and force in avian smooth muscle. FEBS Lett 2006; 580:5779-84. [PMID: 17022978 PMCID: PMC1698950 DOI: 10.1016/j.febslet.2006.09.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 08/28/2006] [Accepted: 09/15/2006] [Indexed: 11/17/2022]
Abstract
In avian smooth muscles, GTPgammaS produces a Rho kinase mediated increase in PHI-1 phosphorylation and force, but whether this correlation is causal is unknown. We examined the effect of phosphorylated PHI-1 (P-PHI-1) on force and myosin light chain (MLC(20)) phosphorylation at a constant [Ca(2+)]. P-PHI-1, but not PHI-1, increased MLC(20) phosphorylation and force, and phosphorylation of PHI-1 increased the interaction of PHI-1 with PP1c. Microcystin induced a dose-dependent reduction in the binding of PHI-1 to PP1c. These results suggest PHI-1 inhibits myosin light chain phosphatase by interacting with the active site of PP1c to produce a Ca(2+) independent increase in MLC(20) phosphorylation and force.
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Affiliation(s)
- Amr El-Toukhy
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Allison M Given
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, 55905 and
| | - Ozgur Ogut
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, 55905 and
| | - Frank V Brozovich
- Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, 55905 and
- Address for correspondence: Frank Brozovich, Division of Cardiovascular Diseases, Mayo Clinic, Guggenheim 9C, 200 1 Street SW, Rochester, MN 55905 USA, , 1-507-266-0324, FAX 1-507-284-8566
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49
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Tsai MH, Jiang MJ. Rho-kinase-mediated regulation of receptor-agonist-stimulated smooth muscle contraction. Pflugers Arch 2006; 453:223-32. [PMID: 16953424 DOI: 10.1007/s00424-006-0133-y] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2005] [Accepted: 12/22/2005] [Indexed: 11/30/2022]
Abstract
Rho kinase was shown to regulate smooth muscle contraction through modulating myosin phosphatase (MLCP) activity, but the in vivo mechanism remains to be clarified. This study examined the effects of Rho kinase inhibition on the phosphorylation time course of MLCP subunit MYPT1 at Thr697 and Thr855 and MLCP inhibitory protein CPI-17 at Thr38 and on actin polymerization during the contraction of rat tail artery (RTA) smooth muscle. Rho kinase inhibitor Y27632 suppressed force activated by alpha(1)-adrenergic agonist phenylephrine or thromboxane A(2) analog U46619 with concomitant decreases in MLC(20) phosphorylation. Phenylephrine and U46619 significantly increased MYPT1(Thr855) phosphorylation that was eliminated by Y27632 pretreatment, whereas MYPT1(Thr697) phosphorylation was not stimulated. Phenylephrine increased CPI-17(Thr38) phosphorylation that was not inhibited by Y27632 but was abolished by a protein kinase C inhibitor Ro 31-8220; in contrast, U46619 did not stimulate CPI-17 phosphorylation. Both agonists increased actin polymerization that was diminished by Y27632 under phenylephrine but not U46619 activation. These results demonstrated a temporal correlation between MYPT1(Thr855) phosphorylation, MLC(20) phosphorylation, and contraction in a Rho-kinase-dependent manner for both phenylephrine and U46619 stimulation, suggesting that Rho kinase regulates MLCP activity through MYPT1(Thr855) phosphorylation during RTA smooth muscle contraction. Furthermore, Rho kinase regulates actin polymerization activated by alpha(1)-adrenoceptors but is less significant in thromboxane receptor stimulation.
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Affiliation(s)
- Ming-Ho Tsai
- Institute of Basic Medical Sciences, National Cheng-Kung University College of Medicine, Tainan, Taiwan
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50
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Abstract
Phosphorylation of Ser19 on the 20-kDa regulatory light chain of myosin II (MLC20) by Ca2+/calmodulin-dependent myosin light-chain kinase (MLCK) is essential for initiation of smooth muscle contraction. The initial [Ca2+]i transient is rapidly dissipated and MLCK inactivated, whereas MLC20 and muscle contraction are well maintained. Sustained contraction does not reflect Ca2+ sensitization because complete inhibition of MLC phosphatase activity in the absence of Ca2+ induces smooth muscle contraction. This contraction is suppressed by staurosporine, implying participation of a Ca2+-independent MLCK. Thus, sustained contraction, as with agonist-induced contraction at experimentally fixed Ca2+ concentrations, involves (a) G protein activation, (b) regulated inhibition of MLC phosphatase, and (c) MLC20 phosphorylation via a Ca2+-independent MLCK. The pathways that lead to inhibition of MLC phosphatase by G(q/13)-coupled receptors are initiated by sequential activation of Galpha(q)/alpha13, RhoGEF, and RhoA, and involve Rho kinase-mediated phosphorylation of the regulatory subunit of MLC phosphatase (MYPT1) and/or PKC-mediated phosphorylation of CPI-17, an endogenous inhibitor of MLC phosphatase. Sustained MLC20 phosphorylation is probably induced by the Ca2+-independent MLCK, ZIP kinase. The pathways initiated by G(i)-coupled receptors involve sequential activation of Gbetagamma(i), PI 3-kinase, and the Ca2+-independent MLCK, integrin-linked kinase. The last phosphorylates MLC20 directly and inhibits MLC phosphatase by phosphorylating CPI-17. PKA and PKG, which mediate relaxation, act upstream to desensitize the receptors (VPAC2 and NPR-C), inhibit adenylyl and guanylyl cyclase activities, and stimulate cAMP-specific PDE3 and PDE4 and cGMP-specific PDE5 activities. These kinases also act downstream to inhibit (a) initial contraction by inhibiting Ca2+ mobilization and (b) sustained contraction by inhibiting RhoA and targets downstream of RhoA. This increases MLC phosphatase activity and induces MLC20 dephosphorylation and muscle relaxation.
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Affiliation(s)
- Karnam S Murthy
- Department of Physiology, Virginia Commonwealth University Medical Center, Richmond, Virginia 23298, USA.
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