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Neumann J, Hofmann B, Kirchhefer U, Dhein S, Gergs U. Function and Role of Histamine H 1 Receptor in the Mammalian Heart. Pharmaceuticals (Basel) 2023; 16:ph16050734. [PMID: 37242517 DOI: 10.3390/ph16050734] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 05/05/2023] [Accepted: 05/09/2023] [Indexed: 05/28/2023] Open
Abstract
Histamine can change the force of cardiac contraction and alter the beating rate in mammals, including humans. However, striking species and regional differences have been observed. Depending on the species and the cardiac region (atrium versus ventricle) studied, the contractile, chronotropic, dromotropic, and bathmotropic effects of histamine vary. Histamine is present and is produced in the mammalian heart. Thus, histamine may exert autocrine or paracrine effects in the mammalian heart. Histamine uses at least four heptahelical receptors: H1, H2, H3 and H4. Depending on the species and region studied, cardiomyocytes express only histamine H1 or only histamine H2 receptors or both. These receptors are not necessarily functional concerning contractility. We have considerable knowledge of the cardiac expression and function of histamine H2 receptors. In contrast, we have a poor understanding of the cardiac role of the histamine H1 receptor. Therefore, we address the structure, signal transduction, and expressional regulation of the histamine H1 receptor with an eye on its cardiac role. We point out signal transduction and the role of the histamine H1 receptor in various animal species. This review aims to identify gaps in our knowledge of cardiac histamine H1 receptors. We highlight where the published research shows disagreements and requires a new approach. Moreover, we show that diseases alter the expression and functional effects of histamine H1 receptors in the heart. We found that antidepressive drugs and neuroleptic drugs might act as antagonists of cardiac histamine H1 receptors, and believe that histamine H1 receptors in the heart might be attractive targets for drug therapy. The authors believe that a better understanding of the role of histamine H1 receptors in the human heart might be clinically relevant for improving drug therapy.
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Affiliation(s)
- Joachim Neumann
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Magdeburger Straße 4, Martin-Luther-Universität Halle-Wittenberg, 06097 Halle, Germany
| | - Britt Hofmann
- Herzchirurgie, Medizinische Fakultät, Martin-Luther-Universität Halle-Wittenberg, Ernst-Grube Straße 40, 06097 Halle, Germany
| | - Uwe Kirchhefer
- Institut für Pharmakologie und Toxikologie, Domagkstraße 12, Westfälische Wilhelms-Universität, 48149 Münster, Germany
| | - Stefan Dhein
- Rudolf-Boehm Institut für Pharmakologie und Toxikologie, Härtelstraße 16-18, Universität Leipzig, 04107 Leipzig, Germany
| | - Ulrich Gergs
- Institut für Pharmakologie und Toxikologie, Medizinische Fakultät, Magdeburger Straße 4, Martin-Luther-Universität Halle-Wittenberg, 06097 Halle, Germany
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Chin CG, Elimam AM, Lin FJ, Chen YC, Lin YK, Lu YY, Higa S, Chen SA, Hsieh MH, Chen YJ. Effects of Adrenomedullin on Atrial Electrophysiology and Pulmonary Vein Arrhythmogenesis. Int J Mol Sci 2022; 23:ijms232214064. [PMID: 36430541 PMCID: PMC9696567 DOI: 10.3390/ijms232214064] [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: 10/28/2022] [Revised: 11/10/2022] [Accepted: 11/14/2022] [Indexed: 11/16/2022] Open
Abstract
Adrenomedullin, a peptide with vasodilatory, natriuretic, and diuretic effects, may be a novel agent for treating heart failure. Heart failure is associated with an increased risk of atrial fibrillation (AF), but the effects of adrenomedullin on atrial arrhythmogenesis remain unclear. This study investigated whether adrenomedullin modulates the electrophysiology of the atria (AF substrate) or pulmonary vein (PV; AF trigger) arrhythmogenesis. Conventional microelectrode or whole-cell patch clamps were used to study the effects of adrenomedullin (10, 30, and 100 pg/mL) on the electrical activity, mechanical response, and ionic currents of isolated rabbit PV and sinoatrial node tissue preparations and single PV cardiomyocytes. At 30 and 100 pg/mL, adrenomedullin significantly reduced the spontaneous beating rate of the PVs from 2.0 ± 0.4 to 1.3 ± 0.5 and 1.1 ± 0.5 Hz (reductions of 32.9% ± 7.1% and 44.9 ± 8.4%), respectively, and reduced PV diastolic tension by 12.8% ± 4.1% and 14.5% ± 4.1%, respectively. By contrast, adrenomedullin did not affect sinoatrial node beating. In the presence of L-NAME (a nitric oxide synthesis inhibitor, 100 μM), adrenomedullin (30 pg/mL) did not affect the spontaneous beating rate or diastolic tension of the PVs. In the single-cell experiments, adrenomedullin (30 pg/mL) significantly reduced the L-type calcium current (ICa-L) and reverse-mode current of the sodium-calcium exchanger (NCX). Adrenomedullin reduces spontaneous PV activity and PV diastolic tension by reducing ICa-L and NCX current and thus may be useful for treating atrial tachyarrhythmia.
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Affiliation(s)
- Chye-Gen Chin
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, 111 Hsin-Lung Road, Sec. 3, Taipei 11696, Taiwan
| | - Ahmed Moustafa Elimam
- Division of Cardiovascular Medicine, Department of Internal Medicine, Mansoura International Hospital, Mansoura 35511, Egypt
| | - Fong-Jhih Lin
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
- Department of Biomedical Engineering, National Defense Medical Center, Taipei 11490, Taiwan
| | - Yao-Chang Chen
- Department of Biomedical Engineering, National Defense Medical Center, Taipei 11490, Taiwan
| | - Yung-Kuo Lin
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, 111 Hsin-Lung Road, Sec. 3, Taipei 11696, Taiwan
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
| | - Yen-Yu Lu
- Division of Cardiology, Department of Internal Medicine, Sijhih Cathay General Hospital, New Taipei City 22174, Taiwan
| | - Satoshi Higa
- Cardiac Electrophysiology and Pacing Laboratory, Division of Cardiovascular Medicine, Makiminato Central Hospital, Okinawa 901-2131, Japan
| | - Shih-Ann Chen
- Department of Post-Baccalaureate Medicine, College of Medicine, National Chung Hsing University, Taichung 40227, Taiwan
- Cardiovascular Center, Taichung Veterans General Hospital, Taichung 40705, Taiwan
| | - Ming-Hsiung Hsieh
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, 111 Hsin-Lung Road, Sec. 3, Taipei 11696, Taiwan
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
- Correspondence: (M.-H.H.); (Y.-J.C.); Tel.: +886-0970746502 (Y.-J.C.); Fax: +886-2-2933-9378 (Y.-J.C.)
| | - Yi-Jen Chen
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan
- Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, 111 Hsin-Lung Road, Sec. 3, Taipei 11696, Taiwan
- Correspondence: (M.-H.H.); (Y.-J.C.); Tel.: +886-0970746502 (Y.-J.C.); Fax: +886-2-2933-9378 (Y.-J.C.)
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Tsuruda T, Kato J, Kuwasako K, Kitamura K. Adrenomedullin: Continuing to explore cardioprotection. Peptides 2019; 111:47-54. [PMID: 29577955 DOI: 10.1016/j.peptides.2018.03.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/15/2018] [Accepted: 03/19/2018] [Indexed: 10/17/2022]
Abstract
Adrenomedullin (AM), a peptide isolated from an extract of human pheochromocytoma, comprises 52 amino acids with an intramolecular disulfide bond and amidation at the carboxy-terminus. AM is present in various tissues and organs in rodents and humans, including the heart. The peptide concentration increases with cardiac hypertrophy, acute myocardial infarction, and overt heart failure in the plasma and the myocardium. The principal function of AM in the cardiovascular system is the regulation of the vascular tone by vasodilation and natriuresis via cyclic adenosine monophosphate-dependent or -independent mechanism. In addition, AM may possess unique properties that inhibit aldosterone secretion, oxidative stress, apoptosis, and stimulation of angiogenesis, resulting in the protection of the structure and function of the heart. The AM receptor comprises a complex between calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein (RAMP) 2 or 3, and the AM-CLR/RAMP2 system is essential for heart development during embryogenesis. Small-scale clinical trials have proven the efficacy and safety of recombinant AM peptide therapy for heart failure. Gene delivery and a modified AM peptide that prolongs the half-life of the native peptide could be an innovative method to improve the efficacy and benefit of AM in clinical settings. In this review, we focus on the pathophysiological roles of AM and its receptor system in the heart and describe the advances in AM and proAM-derived peptides as diagnostic biomarkers as well as the therapeutic application of AM and modified AM for cardioprotection.
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Affiliation(s)
- Toshihiro Tsuruda
- Department of Internal Medicine, Circulatory and Body Fluid Regulation, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan.
| | - Johji Kato
- Frontier Science Research Center, Faculty of Medicine, University of Miyazaki, Japan
| | - Kenji Kuwasako
- Frontier Science Research Center, Faculty of Medicine, University of Miyazaki, Japan
| | - Kazuo Kitamura
- Department of Internal Medicine, Circulatory and Body Fluid Regulation, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miyazaki 889-1692, Japan
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Zhang QH, Hao JW, Li GL, Ji XJ, Yao XD, Dong N, Yao YM. Proinflammatory switch from Gαs to Gαi signaling by Glucagon-like peptide-1 receptor in murine splenic monocyte following burn injury. Inflamm Res 2017; 67:157-168. [PMID: 29022064 DOI: 10.1007/s00011-017-1104-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Revised: 09/26/2017] [Accepted: 09/30/2017] [Indexed: 01/04/2023] Open
Abstract
OBJECTIVE Glucagon-like peptide-1 (GLP-1)-based therapy via G protein-coupled receptor (GPCR) GLP-1R, to attenuate hyperglycemia in critical care has attracted great attention. However, the exaggerated inflammation by GLP-1R agonist, Exendin-4, in a mouse model of burn injury was quite unexpected. Recent studies found that GPCR might elicit proinflammatory effects by switching from Gαs to Gαi signaling in the immune system. Thus, we aimed to investigate the possible Gαs to Gαi switch in GLP-1R signaling in monocyte following burn injury. MATERIALS AND METHODS Splenic monocytes from sham and burn mice 24 h following burn injury were treated with consecutive doses of Exendin-4 alone or in combination with an inhibitor of Gαi signaling (pertussis toxin, PTX), or a blocker of protein kinase A (H89). Cell viability was assessed by CCK-8, and the supernatant was collected for cytokine measurement by ELISA. Intracellular cAMP level, phosphorylated PKA activity, and nuclear NF-κB p65 were determined by ELISA, ERK1/2 activation was analyzed by Western blot. The expression of GLP-1R downstream molecules, Gαs, Gαi and G-protein coupled receptor kinase 2 (GRK2) were examined by immunofluorescence staining and Western blot. RESULTS Exendin-4 could inhibit the viability of monocyte from sham rather than burn mice. Unexpectedly, it could also reduce TNF-α secretion from sham monocyte while increase it from burn monocyte. The increased secretion of TNF-α by Exendin-4 from burn monocyte could be reversed by pretreatment of PTX or H89. Accordingly, Exendin-4 could stimulates cAMP production dose dependently from sham instead of burn monocyte. However, the blunt cAMP production from burn monocyte was further suppressed by pretreatment of PTX or H89 after 6-h incubation. Nevertheless, phosphorylated PKA activity was significantly increased by low dose of Exendin-4 in sham monocyte, by contrast, it was enhanced by high dose of Exendin-4 in burn monocyte after 1-h incubation. Following Exendin-4 treatment for 2 h ex vivo, total nuclear NF-κB and phosphorylated NF-κB activity, as well as cytoplasmic pERK1/2 expressions were reduced in sham monocyte, however, only pERK1/2 was increased by Exendin-4 in burn monocytes. Moreover, reduced expressions of GLP-1R, GRK-2 and Gαs in contrast with increased expression of Gαi were identified in burn monocyte relative to sham monocyte. CONCLUSIONS This study presents an unexpected proinflammatory switch from Gαs to Gαi signaling in burn monocyte, which promotes ERK1/2 and NF-κB activation and the downstream TNF-α secretion. This phenomenon is most probably responsible for proinflammatory response evoked by Gαs agonist Exendin-4 following burn injury.
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Affiliation(s)
- Qing-Hong Zhang
- Department of Microbiology and Immunology, Burns' Institute, First Hospital Affiliated to the Chinese PLA General Hospital, 51 Fucheng Road, Haidian District, Beijing, 100048, People's Republic of China.
| | - Ji-Wei Hao
- Department of Microbiology and Immunology, Burns' Institute, First Hospital Affiliated to the Chinese PLA General Hospital, 51 Fucheng Road, Haidian District, Beijing, 100048, People's Republic of China
| | - Guang-Lei Li
- Department of Microbiology and Immunology, Burns' Institute, First Hospital Affiliated to the Chinese PLA General Hospital, 51 Fucheng Road, Haidian District, Beijing, 100048, People's Republic of China
| | - Xiao-Jing Ji
- Department of Emergency, First Hospital Affiliated to Wenzhou Medical College, Wenzhou, 325000, People's Republic of China
| | - Xu-Dong Yao
- Department of Emergency, First Hospital Affiliated to Wenzhou Medical College, Wenzhou, 325000, People's Republic of China
| | - Ning Dong
- Department of Microbiology and Immunology, Burns' Institute, First Hospital Affiliated to the Chinese PLA General Hospital, 51 Fucheng Road, Haidian District, Beijing, 100048, People's Republic of China
| | - Yong-Ming Yao
- Department of Microbiology and Immunology, Burns' Institute, First Hospital Affiliated to the Chinese PLA General Hospital, 51 Fucheng Road, Haidian District, Beijing, 100048, People's Republic of China. .,State Key Laboratory of Kidney Disease, The Chinese PLA General Hospital, Beijing, 100853, People's Republic of China.
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Wang D, Zeng J, Li Q, Huang J, Couture R, Hong Y. Contribution of adrenomedullin to the switch of G protein-coupled μ-opioid receptors from Gi to Gs in the spinal dorsal horn following chronic morphine exposure in rats. Br J Pharmacol 2016; 173:1196-207. [PMID: 26750148 DOI: 10.1111/bph.13419] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 12/30/2015] [Accepted: 01/07/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Chronic exposure to morphine increases spinal adrenomedullin (AM) bioactivity resulting in the development and maintenance of morphine tolerance. This study investigated the possible involvement of AM in morphine-evoked alteration in μ-opioid receptor-coupled G proteins. EXPERIMENTAL APPROACH Agents were administered intrathecally (i.t.) in rats. Nociceptive behaviours and cumulative dose-response of morphine analgesia were assessed. Neurochemicals in the spinal dorsal horn were assayed by immunoprecipitation, Western blot analysis and ELISA. KEY RESULTS Intrathecal injection of AM (8 μg) for 9 days decreased and increased the levels of μ receptor-coupled Gi and Gs proteins respectively. Morphine stimulation (5 μg) after chronic treatment with AM also induced an increase in cAMP production in the spinal dorsal horn. Co-administration of the selective AM receptor antagonist AM22-52 inhibited chronic morphine-evoked switch of G protein-coupled μ receptor from Gi to Gs. Chronic exposure to AM increased the phosphorylation of cAMP-responsive element-binding protein (CREB) and ERK. Co-administration of the PKA inhibitor H-89 (5 μg) or MEK1 inhibitor PD98059 (1 μg) reversed the AM-induced thermal/mechanical hypersensitivity, decline in morphine analgesic potency, switch of G protein-coupled μ receptor and increase in cAMP. CONCLUSIONS AND IMPLICATIONS The present study supports the hypothesis that an increase in AM activity in the spinal dorsal horn contributes to the switch of the μ receptor-coupled G protein from Gi to Gs protein via the activation of cAMP/PKA/CREB and ERK signalling pathways in chronic morphine use.
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Affiliation(s)
- Dongmei Wang
- College of Life Sciences and Provincial Key Laboratory of Developmental Biology and Neuroscience, Fujian Normal University, Fuzhou, Fujian, China
| | - Juan Zeng
- College of Life Sciences and Provincial Key Laboratory of Developmental Biology and Neuroscience, Fujian Normal University, Fuzhou, Fujian, China
| | - Qi Li
- College of Life Sciences and Provincial Key Laboratory of Developmental Biology and Neuroscience, Fujian Normal University, Fuzhou, Fujian, China
| | - Jianzhong Huang
- College of Life Sciences and Provincial Key Laboratory of Developmental Biology and Neuroscience, Fujian Normal University, Fuzhou, Fujian, China
| | - Réjean Couture
- Department of Molecular and Integrative Physiology, Faculty of Medicine, Université de Montréal, Montréal, QC, Canada
| | - Yanguo Hong
- College of Life Sciences and Provincial Key Laboratory of Developmental Biology and Neuroscience, Fujian Normal University, Fuzhou, Fujian, China
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Chang JR, Guo J, Wang Y, Hou YL, Lu WW, Zhang JS, Yu YR, Xu MJ, Liu XY, Wang XJ, Guan YF, Zhu Y, Du J, Tang CS, Qi YF. Intermedin1-53 attenuates vascular calcification in rats with chronic kidney disease by upregulation of α-Klotho. Kidney Int 2016; 89:586-600. [PMID: 26880455 DOI: 10.1016/j.kint.2015.12.029] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 11/18/2015] [Accepted: 12/03/2015] [Indexed: 01/19/2023]
Abstract
Deficiency in α-Klotho is involved in the pathogenesis of vascular calcification. Since intermedin (IMD)1-53 (a calcitonin/calcitonin gene-related peptide) protects against vascular calcification, we studied whether IMD1-53 inhibits vascular calcification by upregulating α-Klotho. A rat model of chronic kidney disease (CKD) with vascular calcification induced by the 5/6 nephrectomy plus vitamin D3 was used for study. The aortas of rats with CKD showed reduced IMD content but an increase of its receptor, calcitonin receptor-like receptor, and its receptor modifier, receptor activity-modifying protein 3. IMD1-53 treatment reduced vascular calcification. The expression of α-Klotho was greatly decreased in the aortas of rats with CKD but increased in the aortas of IMD1-53-treated rats with CKD. In vitro, IMD1-53 increased α-Klotho protein level in calcified vascular smooth muscle cells. α-Klotho knockdown blocked the inhibitory effect of IMD1-53 on vascular smooth muscle cell calcification and their transformation into osteoblast-like cells. The effect of IMD1-53 to upregulate α-Klotho and inhibit vascular smooth muscle cell calcification was abolished by knockdown of its receptor or its modifier protein, or treatment with the protein kinase A inhibitor H89. Thus, IMD1-53 may attenuate vascular calcification by upregulating α-Klotho via the calcitonin receptor/modifying protein complex and protein kinase A signaling.
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Affiliation(s)
- Jin Rui Chang
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China; Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China; Insititute of Basic Medicine Science, Xi'an Medical University, Xi'an, China
| | - Jun Guo
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China
| | - Yue Wang
- Renal Department, Peking University Third Hospital, Beijing, China
| | - Yue Long Hou
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China; Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Wei Wei Lu
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China; Department of Pathogen Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Jin Sheng Zhang
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China; Department of Pathogen Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Yan Rong Yu
- Department of Pathogen Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Ming Jiang Xu
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Xiu Ying Liu
- Key Laboratory of Genetic Network Biology, Collaborative Innovation Center of Genetics and Development, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Xiu Jie Wang
- Key Laboratory of Genetic Network Biology, Collaborative Innovation Center of Genetics and Development, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - You Fei Guan
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Yi Zhu
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Jie Du
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China
| | - Chao Shu Tang
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China; Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China
| | - Yong Fen Qi
- The Key Laboratory of Remodeling-related Cardiovascular Diseases, Capital Medical University, Ministry of Education, Beijing, China; Beijing Institute of Heart Lung and Blood Vessel Diseases, Beijing Anzhen Hospital Affiliated with the Capital Medical University, Beijing, China; Key Laboratory of Molecular Cardiovascular Science, Ministry of Education, Peking University Health Science Center, Beijing, China; Department of Pathogen Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.
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Dysregulation of intracellular calcium transporters in animal models of sepsis-induced cardiomyopathy. Shock 2015; 43:3-15. [PMID: 25186837 DOI: 10.1097/shk.0000000000000261] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Sepsis-induced cardiomyopathy (SIC) develops as the result of myocardial calcium (Ca) dysregulation. Here we reviewed all published studies that quantified the dysfunction of intracellular Ca transporters and the myofilaments in animal models of SIC. Cardiomyocytes isolated from septic animals showed, invariably, a decreased twitch amplitude, which is frequently caused by a decrease in the amplitude of cellular Ca transients (ΔCai) and sarcoplasmic reticulum (SR) Ca load (CaSR). Underlying these deficits, the L-type Ca channel is downregulated, through mechanisms that may involve adrenomedullin-mediated redox signaling. The SR Ca pump is also inhibited, through oxidative modifications (sulfonylation) of one reactive thiol group (on Cys) and/or modulation of phospholamban. Diastolic Ca leak of ryanodine receptors is frequently increased. In contrast, Na/Ca exchange inhibition may play a partially compensatory role by increasing CaSR and ΔCai. The action potential is usually shortened. Myofilaments show a bidirectional regulation, with decreased Ca sensitivity in milder forms of disease (due to troponin I hyperphosphorylation) and an increase (redox mediated) in more severe forms. Most deficits occurred similarly in two different disease models, induced by either intraperitoneal administration of bacterial lipopolysaccharide or cecal ligation and puncture. In conclusion, substantial cumulative evidence implicates various Ca transporters and the myofilaments in SIC pathology. What is less clear, however, are the identity and interplay of the signaling pathways that are responsible for Ca transporters dysfunction. With few exceptions, all studies we found used solely male animals. Identifying sex differences in Ca dysregulation in SIC becomes, therefore, another priority.
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Cao X, Zhou C, Chong J, Fu L, Zhang L, Sun D, Hou H, Zhang Y, Li D, Sun H. Estrogen resisted stress-induced cardiomyopathy through increasing the activity of β2AR–Gαs signal pathway in female rats. Int J Cardiol 2015; 187:377-86. [DOI: 10.1016/j.ijcard.2015.02.113] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 02/16/2015] [Accepted: 02/21/2015] [Indexed: 02/08/2023]
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Chang JR, Duan XH, Zhang BH, Teng X, Zhou YB, Liu Y, Yu YR, Zhu Y, Tang CS, Qi YF. Intermedin1-53 attenuates vascular smooth muscle cell calcification by inhibiting endoplasmic reticulum stress via cyclic adenosine monophosphate/protein kinase A pathway. Exp Biol Med (Maywood) 2013; 238:1136-46. [PMID: 24006303 DOI: 10.1177/1535370213502619] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We previously reported that endoplasmic reticulum (ER) stress-mediated apoptosis participated in vascular calcification. Importantly, a novel paracrine/autocrine peptide intermedin1-53 (IMD1-53) in the vasculature inhibited vascular calcification in rats. But the mechanisms needed to be fully elucidated. Vascular smooth muscle cells (VSMCs) calcification was induced by CaCl2 and β-glycerophosphate. Tunicamycin (Tm) or dithiothreitol (DTT) was used to induce ER stress. We found that IMD1-53 (10(-7)mol/L) treatment significantly alleviated the protein expression of ER stress hallmarks activating transcription factor 4 (ATF4), ATF6, glucose-regulated protein 78 (GRP78) and GRP94 induced by Tm or DTT. ER stress occurred in early and late calcification of VSMCs but was inhibited by IMD1-53. These inhibitory effects of IMD1-53 were abolished by treatment with the protein kinase A (PKA) inhibitor H89. Pretreatment with IMD1-53 decreased the number of apoptotic VSMCs and downregulated protein expression of cleaved caspase 12 and C/EBP homologous protein (CHOP) in calcified VSMCs. Concurrently, IMD1-53 restored the loss of VSMC lineage markers and ameliorated calcium deposition and alkaline phosphatase activity in calcified VSMCs as well. The observation was further verified by Alizarin Red S staining, which showed that IMD1-53 reduced positive red nodules among calcified VSMCs. In conclusion, IMD1-53 attenuated VSMC calcification by inhibiting ER stress through cAMP/PKA signalling.
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Affiliation(s)
- Jin-Rui Chang
- Department of Physiology and Pathophysiology, School of Basic Medical Science, Peking University Health Science Center, Beijing 100191, China
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Li P, Sun HJ, Han Y, Wang JJ, Zhang F, Tang CS, Zhou YB. Intermedin enhances sympathetic outflow via receptor-mediated cAMP/PKA signaling pathway in nucleus tractus solitarii of rats. Peptides 2013; 47:1-6. [PMID: 23816795 DOI: 10.1016/j.peptides.2013.05.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Revised: 05/07/2013] [Accepted: 05/07/2013] [Indexed: 10/26/2022]
Abstract
Direct administration of intermedin (IMD) into the brain elicits cardiovascular effects different from the systemic administration. Nucleus tractus solitarii (NTS) is an important region for the cardiovascular regulation. The present study was designed to determine the effect of IMD on modulating the sympathetic outflow and its related molecular mechanism in the NTS. Renal sympathetic nerve activity (RSNA) and mean arterial pressure (MAP) were recorded in anesthetized rats. Site-specific microinjection of IMD (20pmol) bilaterally into the NTS significantly increased RSNA and MAP. IMD-evoked increases of RSNA and MAP were almost abolished by pretreatment with receptor antagonist ADM22-52, an adenylyl cyclase (AC) inhibitor SQ22536, or a protein kinase A (PKA) inhibitor Rp-cAMP. However, pretreatment with another receptor antagonist calcitonin gene-related peptide (CGRP)8-37 did not suppress the increases of RSNA and MAP induced by IMD. Furthermore, IMD increased the cyclic adenosine monophosphate (cAMP) level, which was inhibited by ADM22-52 pretreatment in the NTS. These results suggest that IMD participates in the sympathetic nerve activity and central regulation of the cardiovascular system and a receptor-mediated cAMP/PKA signaling pathway is involved in IMD-induced effects in the NTS.
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Affiliation(s)
- Peng Li
- Department of Physiology, Nanjing Medical University, Nanjing 210029, China
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11
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Wang D, Ruan L, Hong Y, Chabot JG, Quirion R. Involvement of PKA-dependent upregulation of nNOS-CGRP in adrenomedullin-initiated mechanistic pathway underlying CFA-induced response in rats. Exp Neurol 2012; 239:111-9. [PMID: 23063906 DOI: 10.1016/j.expneurol.2012.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2012] [Revised: 09/30/2012] [Accepted: 10/04/2012] [Indexed: 11/28/2022]
Abstract
We have previously shown that intrathecal administration of the adrenomedullin (AM) receptor antagonist AM(22-52) produces a long-lasting anti-hyperalgesia effect. This study examined the hypothesis that AM recruits other pronociceptive mediators in complete Freund's adjuvant (CFA)-induced inflammation. Injection of CFA in the hindpaw of rat produced an increase in the expression of nNOS in dorsal root ganglion (DRG) and the spinal dorsal horn. An intrathecal administration of AM(22-52), but not the CGRP antagonist BIBN4096BS, abolished the CFA-induced increase of nNOS. Moreover, AM-induced increase of CGRP was inhibited by the nNOS inhibitors L-NAME and 7-nitroindazole in cultured ganglion explants. Addition of AM to ganglion cultures induced an increase in nNOS protein, which was attenuated by the PKA inhibitor H-89. Treatment with AM also concentration-dependently increased cAMP content and pPKA protein level, but not its non-phosphorylated form, in cultured ganglia. In addition, nNOS was shown to be co-localized with the AM receptor components calcitonin receptor-like receptor and receptor activity-modifying protein 2- and 3 in DRG neurons. The present study suggests that the enhanced activity of nitric oxide (NO) mediates the biological action of AM at the spinal level and that AM recruits NO-CGRP via cAMP/PKA signaling in a mechanistic pathway underlying CFA-induced hyperalgesia.
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Affiliation(s)
- Dongmei Wang
- Provincial Key Laboratory of Developmental Biology and Neuroscience, Fujian Normal University, Fuzhou, Fujian, 350108, China
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12
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Current progress in non-Edg family LPA receptor research. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:33-41. [PMID: 22902318 DOI: 10.1016/j.bbalip.2012.08.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 08/01/2012] [Accepted: 08/02/2012] [Indexed: 01/08/2023]
Abstract
Lysophosphatidic acid (LPA) is the simplest phospholipid yet possesses myriad biological functions. Until 2003, the functions of LPA were thought to be elicited exclusively by three subtypes of the endothelial differentiation gene (Edg) family of G protein-coupled receptors - LPA(1), LPA(2), and LPA(3). However, several biological functions of LPA could not be assigned to any of these receptors indicating the existence of one or more additional LPA receptor(s). More recently, the discovery of a second cluster of LPA receptors which includes LPA(4), LPA(5), and LPA(6) has paved the way for new avenues of LPA research. Analyses of these non-Edg family LPA receptors have begun to fill in gaps to understand biological functions of LPA such as platelet aggregation and vascular development that could not be ascribed to classical Edg family LPA receptors and are also unveiling new biological functions. Here we review recent progress in the non-Edg family LPA receptor research, with special emphasis on the pharmacology, signaling, and physiological roles of this family of receptors. This article is part of a Special Issue entitled Advances in Lysophospholipid Research.
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13
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Abstract
Adrenomedullin 2 (AM2) or intermedin is a member of the calcitonin gene-related peptide (CGRP)/calcitonin family of peptides and was discovered in 2004. Unlike other members of this family, no unique receptor has yet been identified for it. It is extensively distributed throughout the body. It causes hypotension when given peripherally, but when given into the CNS, it increases blood pressure and causes sympathetic activation. It also increases prolactin release, is anti-diuretic and natriuretic and reduces food intake. Whilst its effects resemble those of AM, it is frequently more potent. Some characterization of AM2 has been done on molecularly defined receptors; the existing data suggest that it preferentially activates the AM(2) receptor formed from calcitonin receptor-like receptor and receptor activity modifying protein 3. On this complex, its potency is generally equivalent to that of AM. There is no known receptor-activity where it is more potent than AM. In tissues and in animals it is frequently antagonised by CGRP and AM antagonists; however, situations exist in which an AM2 response is maintained even in the presence of supramaximal concentrations of these antagonists. Thus, there is a partial mismatch between the pharmacology seen in tissues and that on cloned receptors. The only AM2 antagonists are peptide fragments, and these have limited selectivity. It remains unclear as to whether novel AM2 receptors exist or whether the mismatch in pharmacology can be explained by factors such as metabolism.
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MacManus CF, Campbell EL, Keely S, Burgess A, Kominsky DJ, Colgan SP. Anti-inflammatory actions of adrenomedullin through fine tuning of HIF stabilization. FASEB J 2011; 25:1856-64. [PMID: 21350119 DOI: 10.1096/fj.10-170316] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In intact mucosal tissues, epithelial cells are anatomically positioned in proximity to a number of subepithelial cell types, including endothelia. A number of recent studies have suggested that imbalances between energy supply and demand can result in "inflammatory hypoxia." Given these associations, we hypothesized that endothelial-derived, hypoxia-inducible mediators might influence epithelial function. Guided by cDNA microarray analysis of human microvascular endothelial cells (HMEC-1 line) subjected to hypoxia (pO(2) 20 torr, 8 h), we identified adrenomedullin (ADM) as a prominent hypoxia-inducible factor (HIF) that acts on epithelial cells through cell surface receptors. We assessed the functional ability for exogenous ADM to signal in human intestinal Caco2 cells in vitro by demonstrating a dose-dependent induction of Erk1/2phosphorylation. Further analysis revealed that ADM deneddylates cullin-2 (Cul2), whose action has been demonstrated to control the activity of HIF. Caco2 cells stably expressing a hypoxic response element (HRE)-driven luciferase promoter confirmed that ADM activates the HIF signaling pathway. Extensions of these studies revealed an increase in canonical HIF-1-dependent genes following stimulation with ADM. To define physiological relevance, we investigated the effect of ADM in a DSS model of murine colitis. Administration of ADM resulted in reduced inflammatory indices and less severe histological inflammation compared to vehicle controls. Analysis of tissue and serum cytokines showed a marked and significant inhibition of colitis-associated TNF-α, IL-1β, and KC. Analysis of circulating ADM demonstrated an increase in serum ADM in murine models of colitis. Taken together, these results identify ADM as an endogenously generated vascular mediator that functions as a mucosal protective factor through fine tuning of HIF activity.
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Affiliation(s)
- Christopher F MacManus
- Department of Medicine, University of Colorado Health Sciences Center, Aurora, Colorado, USA
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Marshall M, Anilkumar N, Layland J, Walker SJ, Kentish JC, Shah AM, Cave AC. Protein phosphatase 2A contributes to the cardiac dysfunction induced by endotoxemia. Cardiovasc Res 2009; 82:67-76. [PMID: 19201758 PMCID: PMC2652740 DOI: 10.1093/cvr/cvp037] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Aims Sepsis-associated cardiac dysfunction represents an intrinsic impairment of cardiomyocyte function due in part to a decrease in myofilament Ca2+ sensitivity associated with a sustained increase in cardiac troponin I (cTnI) phosphorylation at Ser23/24. Dephosphorylation of cTnI is under regulatory control. Thus, muscarinic and adenosine A1-receptor agonists antagonize β-adrenergic stimulation via activation of protein phosphatase 2A (PP2A). The aim of this study was to determine whether modulation of PP2A and thus cTnI phosphorylation could improve sepsis-induced contractile dysfunction. Methods and results Cardiomyocytes were isolated from control or septic mice 16–18 h after an injection of vehicle or lipopolysaccharide (LPS; 9 mg/kg ip) respectively. Protein expression and phosphatase activity were determined in homogenates of control and septic hearts. Our data showed that LPS significantly increased cTnI phosphorylation at Ser23/24 in cardiomyocytes and reduced contraction amplitude without affecting Ca2+-transients. Treatment of cardiomyocytes with the A1 agonist cyclopentyladenosine (CPA) or the protein kinase A inhibitor H89 significantly attenuated the LPS-induced contractile dysfunction without effect on Ca2+-transients. Co-treatment with CPA and H89 completely reversed the contractile dysfunction. Increased cTnI phosphorylation in septic hearts was associated with a significant reduction in the protein expression of both the catalytic and regulatory subunits (B56α) of PP2A and a decrease in PP2A activity. CPA treatment of septic hearts increased PP2A activity. An increase in the protein expression of demethylated PP2A and a decrease in the PP2A-methyltransferase (PPMT; the methyltransferase that catalyses this reaction) were also observed. Conclusion These data support the hypothesis that sustained cTnI phosphorylation underlies the contractile dysfunction seen in sepsis.
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Affiliation(s)
- Melanie Marshall
- Cardiovascular Division, Department of Cardiology, King's College London, James Black Centre, London SE5 9NU, UK.
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16
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Noubade R, del Rio R, McElvany B, Zachary JF, Millward JM, Wagner DD, Offner H, Blankenhorn EP, Teuscher C. von-Willebrand factor influences blood brain barrier permeability and brain inflammation in experimental allergic encephalomyelitis. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 173:892-900. [PMID: 18688020 DOI: 10.2353/ajpath.2008.080001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Weibel-Palade bodies within endothelial cells are secretory granules known to release von Willebrand Factor (VWF), P-selectin, chemokines, and other stored molecules following histamine exposure. Mice with a disrupted VWF gene (VWFKO) have endothelial cells that are deficient in Weibel-Palade bodies. These mice were used to evaluate the role of VWF and/or Weibel-Palade bodies in Bordetella pertussis toxin-induced hypersensitivity to histamine, a subphenotype of experimental allergic encephalomyelitis, the principal autoimmune model of multiple sclerosis. No significant differences in susceptibility to histamine between wild-type and VWFKO mice were detected after 3 days; however, histamine sensitivity persisted significantly longer in VWFKO mice. Correspondingly, encephalomyelitis onset was earlier, disease was more severe, and blood brain barrier (BBB) permeability was significantly increased in VWFKO mice, as compared with wild-type mice. Moreover, inflammation was selectively increased in the brains, but not spinal cords, of VWFKO mice as compared with wild-type mice. Early increases in BBB permeability in VWFKO mice were not due to increased encephalitogenic T-cell activity since BBB permeability did not differ in adjuvant-treated VWFKO mice as compared with littermates immunized with encephalitogenic peptide plus adjuvant. Taken together, these data indicate that VWF and/or Weibel-Palade bodies negatively regulate BBB permeability changes and autoimmune inflammatory lesion formation within the brain elicited by peripheral inflammatory stimuli.
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Affiliation(s)
- Rajkumar Noubade
- Department of Medicine, University of Vermont, Burlington, VT 05405, USA
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Zhang XH, Li GR, Bourreau JP. The effect of adrenomedullin on the L-type calcium current in myocytes from septic shock rats: signaling pathway. Am J Physiol Heart Circ Physiol 2007; 293:H2888-93. [PMID: 17766482 DOI: 10.1152/ajpheart.00312.2007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Adrenomedullin (ADM) is upregulated in cardiac tissue under various pathophysiological conditions, particularly in septic shock. The intracellular mechanisms involved in the effect of ADM on adult rat ventricular myocytes are still to be elucidated. Ventricular myocytes were isolated from adult rats 4 h after an intraperitoneal injection of lipopolysaccharide (LPS, 10 mg/kg). Membrane potential and L-type calcium current ( ICa,L) were determined using whole cell patch-clamp methods. APD in LPS group was significantly shorter than control values (time to 50% repolarization: LPS, 169 ± 2 ms; control, 257 ± 2 ms, P < 0.05; time to 90% repolarization: LPS, 220 ± 2 ms; control, 305 ± 2 ms, P < 0.05). ICa,Ldensity was significantly reduced in myocytes from the LPS group (−3.2 ± 0.8 pA/pF) compared with that of control myocytes (−6.7 ± 0.3 pA/pF, P < 0.05). The ADM antagonist ADM-(22-52) reversed the shortened APD and abolished the reduction of ICa,Lin shock myocytes. In myocytes from control rats, incubating with ADM for 1 h induced a marked decrease in peak ICa,Ldensity. This effect was reversed by ADM-(22-52). The Giprotein inhibitor, pertussis toxin (PTX), the protein kinase A (PKA) inhibitor, KT-5720, and the specific cyclooxygenase 2 (COX-2) inhibitor, nimesulide, reversed the LPS-induced reduction in peak ICa,L. The results suggest a COX-2-involved PKA-dependent switch from Gscoupled to PTX-sensitive Gicoupling by ADM in adult rat ventricular myocytes. The present study delineates the intracellular pathways involved in ADM-mediated effects on ICa,Lin adult rat ventricular myocytes and also suggests a role of ADM in sepsis.
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Affiliation(s)
- Xiao-Hui Zhang
- Department of Physiology and Institute of Cardiovascular Sciences and Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region of China, Hong Kong, China.
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Dackor R, Caron K. Mice heterozygous for adrenomedullin exhibit a more extreme inflammatory response to endotoxin-induced septic shock. Peptides 2007; 28:2164-70. [PMID: 17889965 PMCID: PMC2121581 DOI: 10.1016/j.peptides.2007.08.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2007] [Revised: 08/14/2007] [Accepted: 08/15/2007] [Indexed: 10/22/2022]
Abstract
Adrenomedullin (AM) is a highly conserved peptide that can act as a potent vasodilator, anti-microbial factor and anti-inflammatory factor. Several studies have implicated diverse roles for AM in regulating the inflammatory and hemodynamic responses to septic shock. Moreover, during sepsis the receptors that mediate AM signaling [calcitonin receptor-like receptor (calcrl) and receptor activity modifying proteins (RAMP) 2 and 3] undergo dynamic and robust changes in their expression. Although numerous studies have used animal models to study the role of administered or increased AM in septic animals, genetic studies to determine the consequences of reduced AM during septic shock have not yet been performed. Here, we used a murine model of lipopolysaccharide (LPS)-induced septic shock to assess the inflammatory response in mice heterozygous for the AM gene. Following LPS challenge, AM(+/-) mice had higher expression of TNF-alpha and IL-1beta than LPS-treated wild-type (WT) controls. Consequently, serum TNF-alpha was also significantly elevated in LPS-treated AM(+/-) mice compared to WT LPS-treated mice. We also observed higher serum levels of liver enzymes, suggesting more advanced end-organ damage in mice with genetically reduced AM. Finally, we found that RAMP2 and calcrl expression levels were markedly reduced in LPS-treated mice, whereas RAMP3 expression was significantly elevated. Importantly, these changes in receptor gene expression were conserved in AM(+/-) mice, demonstrating that AM peptide itself does not impact directly on the expression of the genes encoding its receptors. We, therefore, conclude that during septic shock the dynamic modulation of AM and its receptors primarily functions to dampen the inflammatory response.
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Affiliation(s)
- Ryan Dackor
- Department of Cell & Molecular Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 USA
- Genetics Department, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 USA
| | - Kathleen Caron
- Department of Cell & Molecular Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 USA
- Genetics Department, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599 USA
- *Corresponding Author: Department of Cell & Molecular Physiology, CB # 7545, 6330 MBRB 103 Mason Farm Rd., The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 USA, Phone: (919) 966-5215, FAX: (919) 966-5230, e-mail: Kathleen
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Francis H, Franchitto A, Ueno Y, Glaser S, DeMorrow S, Venter J, Gaudio E, Alvaro D, Fava G, Marzioni M, Vaculin B, Alpini G. H3 histamine receptor agonist inhibits biliary growth of BDL rats by downregulation of the cAMP-dependent PKA/ERK1/2/ELK-1 pathway. J Transl Med 2007; 87:473-87. [PMID: 17334413 PMCID: PMC3751000 DOI: 10.1038/labinvest.3700533] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Histamine regulates many functions by binding to four histamine G-coupled receptor proteins (H1R, H2R, H3R and H4R). As H3R exerts their effects by coupling to Galpha(i/o) proteins reducing adenosine 3', 5'-monophosphate (cAMP) levels (a key player in the modulation of cholangiocyte hyperplasia/damage), we evaluated the role of H3R in the regulation of biliary growth. We posed the following questions: (1) Do cholangiocytes express H3R? (2) Does in vivo administration of (R)-(alpha)-(-)-methylhistamine dihydrobromide (RAMH) (H3R agonist), thioperamide maleate (H3R antagonist) or histamine, in the absence/presence of thioperamide maleate, to bile duct ligated (BDL) rats regulate cholangiocyte proliferation? and (3) Does RAMH inhibit cholangiocyte proliferation by downregulation of cAMP-dependent phosphorylation of protein kinase A (PKA)/extracellular signal-regulated kinase 1/2 (ERK1/2)/ets-like gene-1 (Elk-1)? The expression of H3R was evaluated in liver sections by immunohistochemistry and immunofluorescence, and by real-time PCR in cholangiocyte RNA from normal and BDL rats. BDL rats (immediately after BDL) were treated daily with RAMH, thioperamide maleate or histamine in the absence/presence of thioperamide maleate for 1 week. Following in vivo treatment of BDL rats with RAMH for 1 week, and in vitro stimulation of BDL cholangiocytes with RAMH, we evaluated cholangiocyte proliferation, cAMP levels and PKA, ERK1/2 and Elk-1 phosphorylation. Cholangiocytes from normal and BDL rats express H3R. The expression of H3R mRNA increased in BDL compared to normal cholangiocytes. Histamine decreased cholangiocyte growth of BDL rats to a lower extent than that observed in BDL RAMH-treated rats; histamine-induced inhibition of cholangiocyte growth was partly blocked by thioperamide maleate. In BDL rats treated with thioperamide maleate, cholangiocyte hyperplasia was slightly higher than that of BDL rats. In vitro, RAMH inhibited the proliferation of BDL cholangiocytes. RAMH inhibition of cholangiocyte growth was associated with decreased cAMP levels and PKA/ERK1/2/Elk-1 phosphorylation. Downregulation of cAMP-dependent PKA/ERK1/2/Elk-1 phosphorylation (by activation of H3R) is important in the inhibition of cholangiocyte growth in liver diseases.
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MESH Headings
- Animals
- Bile Ducts/surgery
- Bile Ducts, Intrahepatic/drug effects
- Bile Ducts, Intrahepatic/growth & development
- Bile Ducts, Intrahepatic/pathology
- Cell Proliferation/drug effects
- Cyclic AMP/metabolism
- Cyclic AMP-Dependent Protein Kinases
- Disease Models, Animal
- Down-Regulation/drug effects
- Drug Therapy, Combination
- Gene Expression Regulation, Enzymologic/drug effects
- Histamine/pharmacology
- Histamine Agonists/pharmacology
- Hyperplasia/chemically induced
- Hyperplasia/pathology
- Ligation
- Liver/drug effects
- Liver/metabolism
- Liver/pathology
- MAP Kinase Signaling System
- Male
- Methylhistamines/pharmacology
- Mitogen-Activated Protein Kinase 1/metabolism
- Mitogen-Activated Protein Kinase 3/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Phosphorylation
- Piperidines/pharmacology
- Protein Serine-Threonine Kinases/metabolism
- Rats
- Rats, Inbred F344
- Receptor, EphA8/metabolism
- Receptors, Histamine H3/genetics
- Receptors, Histamine H3/metabolism
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Affiliation(s)
- Heather Francis
- Department of Research and Education, College of Medicine, Scott & White Hospital and The Texas A & M University System Health Science Center, Temple, TX 76504, USA
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