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Lee JM, Kim J, Park SJ, Nam JH, Kim HJ, Kim WK. Regulation of T Lymphocyte Functions through Calcium Signaling Modulation by Nootkatone. Int J Mol Sci 2024; 25:5240. [PMID: 38791278 PMCID: PMC11121628 DOI: 10.3390/ijms25105240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 05/02/2024] [Accepted: 05/06/2024] [Indexed: 05/26/2024] Open
Abstract
Recent advancements in understanding the intricate molecular mechanisms underlying immunological responses have underscored the critical involvement of ion channels in regulating calcium influx, particularly in inflammation. Nootkatone, a natural sesquiterpenoid found in Alpinia oxyphylla and various citrus species, has gained attention for its diverse pharmacological properties, including anti-inflammatory effects. This study aimed to elucidate the potential of nootkatone in modulating ion channels associated with calcium signaling, particularly CRAC, KV1.3, and KCa3.1 channels, which play pivotal roles in immune cell activation and proliferation. Using electrophysiological techniques, we demonstrated the inhibitory effects of nootkatone on CRAC, KV1.3, and KCa3.1 channels in HEK293T cells overexpressing respective channel proteins. Nootkatone exhibited dose-dependent inhibition of channel currents, with IC50 values determined for each channel. Nootkatone treatment did not significantly affect cell viability, indicating its potential safety for therapeutic applications. Furthermore, we observed that nootkatone treatment attenuated calcium influx through activated CRAC channels and showed anti-proliferative effects, suggesting its role in regulating inflammatory T cell activation. These findings highlight the potential of nootkatone as a natural compound for modulating calcium signaling pathways by targeting related key ion channels and it holds promise as a novel therapeutic agent for inflammatory disorders.
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Affiliation(s)
- Ji Min Lee
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Jintae Kim
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Su Jin Park
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Joo Hyun Nam
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Hyun Jong Kim
- Department of Physiology, Dongguk University College of Medicine, 123 Dongdae-ro, Gyeongju 38066, Gyeongsangbuk-do, Republic of Korea; (J.M.L.); (S.J.P.); (J.H.N.)
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
| | - Woo Kyung Kim
- Channelopathy Research Center (CRC), Dongguk University College of Medicine, 32 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea;
- Department of Internal Medicine, Graduate School of Medicine, Dongguk University, 27 Dongguk-ro, Ilsan Dong-gu, Goyang 10326, Gyeonggi-do, Republic of Korea
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Zhang S, Liu Y, Javeed A, Jian C, Sun J, Wu S, Han B. Treatment of allergy: Overview of synthetic anti-allergy small molecules in medicinal chemistry. Eur J Med Chem 2023; 249:115151. [PMID: 36731273 DOI: 10.1016/j.ejmech.2023.115151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/21/2023] [Accepted: 01/23/2023] [Indexed: 01/30/2023]
Abstract
The prevalence of allergic diseases has been continuously increasing over the past few decades, affecting approximately 20-30% of the global population. Allergic reactions to infection of respiratory tract, digestive tract, and skin system involve multiple different targets. The main difficulty of anti-allergy research is how to develop drugs with good curative effect and less side effects by adopting new multi-targets and mechanisms according to the clinical characteristics of different allergic populations and different allergens. This review focuses on information concerning potential therapeutic targets as well as the synthetic anti-allergy small molecules with respect to their medicinal chemistry. The structure-activity relationship and the mechanism of compound-target interaction were highlighted with perspective to histamine-1/4 receptor antagonists, leukotriene biosynthesis, Th2 cytokines inhibitors, and calcium channel blockers. We hope that the study of chemical scaffold modification and optimization for different lead compounds summarized in this review not only lays the foundation for improvement of success rate and efficiency of virtual screening of antiallergic drugs, but also can provide valuable reference for the drug design of related promising research such as allergy, inflammation, and cancer.
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Affiliation(s)
- Shanshan Zhang
- Zhejiang Key Laboratory of Silkworm Bioreactor and Biomedicine, Laboratory of Antiallergy Functional Molecules, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Yi Liu
- Hangzhou Zheda Dixun Biological Gene Engineering Co., LTD., Hangzhou, China
| | - Ansar Javeed
- Zhejiang Key Laboratory of Silkworm Bioreactor and Biomedicine, Laboratory of Antiallergy Functional Molecules, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Cuiqin Jian
- Zhejiang Key Laboratory of Silkworm Bioreactor and Biomedicine, Laboratory of Antiallergy Functional Molecules, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, China
| | - Jinlyu Sun
- Department of Allergy, Beijing Key Laboratory of Precision Medicine for Diagnosis and Treatment of Allergic Diseases, National Clinical Research Center for Dermatologic and Immunologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, 100730, China
| | - Shandong Wu
- Hangzhou Zheda Dixun Biological Gene Engineering Co., LTD., Hangzhou, China
| | - Bingnan Han
- Zhejiang Key Laboratory of Silkworm Bioreactor and Biomedicine, Laboratory of Antiallergy Functional Molecules, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, 310018, China.
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3
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Saito D, Suzuki C, Tanaka S, Hosogi S, Kawaguchi K, Asano S, Okamoto S, Yasuda M, Hirano S, Inui T, Marunaka Y, Nakahari T. Ambroxol-enhanced ciliary beating via voltage-gated Ca 2+ channels in mouse airway ciliated cells. Eur J Pharmacol 2023; 941:175496. [PMID: 36642128 DOI: 10.1016/j.ejphar.2023.175496] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 12/12/2022] [Accepted: 01/05/2023] [Indexed: 01/15/2023]
Abstract
Ambroxol (ABX) facilitates the mucociliary clearance (MC) by enhancing ciliary beating in airways. In this study, we focused on airway ciliary beating enhanced by ABX. However, little is known about the ABX-stimulated Ca2+ signalling activating airway ciliary beating. Airway ciliated cells isolated from mice lungs were observed by a high-speed video microscope, and the activities of beating cilia were assessed by CBF (ciliary beat frequency) and CBD (ciliary bend distance, an index of amplitude). ABX (10 μM) enhanced the CBF and CBD by 30%, and the enhancement was inhibited by nifedipine (20 μM, a L-type voltage-gated Ca2+ channel (CaV) inhibitor), or a Ca2+-free solution (approximately 50%). Pre-treatment with BAPTA-AM (10 μM, a chelator of intracellular Ca2+) abolished ABX-stimulated increases in CBF, CBD and [Ca2+]i. Thus, ABX increases [Ca2+]i (intracellular Ca2+ concentration) by stimulating Ca2+ release from the internal stores and nifedipine-sensitive Ca2+ entry. A previous study demonstrated the expression of CaV1.2 in airway cilia. ABX enhanced CBF, CBD and [Ca2+]i even in a high extracellular K+ concentration (155.5 mM), suggesting that it activates CaV1.2 except by depolarization. These enhancements were inhibited by nifedipine. In conclusion, ABX, which increases [Ca2+]i by stimulating Ca2+ release from internal stores and Ca2+ entry through CaV1.2s, enhanced CBF and CBD in airway ciliated cells. ABX is a novel agonist that modulates CaV1.2 of airway beating cilia to enhance CBF and CBD.
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Affiliation(s)
- Daichi Saito
- Research Laboratory for Epithelial Physiology, Research Organization of Science and Technology, BKC Ritsumeikan University, Kusatsu, 525-8577, Japan; Department of Molecular Physiology, Faculty of Pharmacy, BKC, Ritsumeikan University, Kusatsu, 525-8577, Japan
| | - Chihiro Suzuki
- Laboratory of Pharmacotherapy, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki 569-1094, Japan
| | - Saori Tanaka
- Laboratory of Pharmacotherapy, Faculty of Pharmacy, Osaka Medical and Pharmaceutical University, Takatsuki 569-1094, Japan
| | - Shigekuni Hosogi
- Department of Clinical and Translational Physiology, Kyoto Pharmaceutical University, Kyoto, 607-8414, Japan
| | - Kotoku Kawaguchi
- Department of Molecular Physiology, Faculty of Pharmacy, BKC, Ritsumeikan University, Kusatsu, 525-8577, Japan
| | - Shinji Asano
- Department of Molecular Physiology, Faculty of Pharmacy, BKC, Ritsumeikan University, Kusatsu, 525-8577, Japan
| | - Shohta Okamoto
- Research Laboratory for Epithelial Physiology, Research Organization of Science and Technology, BKC Ritsumeikan University, Kusatsu, 525-8577, Japan; Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Makoto Yasuda
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Shigeru Hirano
- Department of Otolaryngology-Head and Neck Surgery, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto, 602-8566, Japan
| | - Toshio Inui
- Research Laboratory for Epithelial Physiology, Research Organization of Science and Technology, BKC Ritsumeikan University, Kusatsu, 525-8577, Japan; Saisei Mirai Clinics, Moriguchi, 570-0012, Japan
| | - Yoshinori Marunaka
- Research Laboratory for Epithelial Physiology, Research Organization of Science and Technology, BKC Ritsumeikan University, Kusatsu, 525-8577, Japan; Medical Research Institute, Kyoto Industrial Health Association, Kyoto, 604-8472, Japan
| | - Takashi Nakahari
- Research Laboratory for Epithelial Physiology, Research Organization of Science and Technology, BKC Ritsumeikan University, Kusatsu, 525-8577, Japan; Medical Research Institute, Kyoto Industrial Health Association, Kyoto, 604-8472, Japan.
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4
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Farquhar RE, Cheung TT, Logue MJE, McDonald FJ, Devor DC, Hamilton KL. Role of SNARE Proteins in the Insertion of KCa3.1 in the Plasma Membrane of a Polarized Epithelium. Front Physiol 2022; 13:905834. [PMID: 35832483 PMCID: PMC9271999 DOI: 10.3389/fphys.2022.905834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 06/01/2022] [Indexed: 11/29/2022] Open
Abstract
Targeting proteins to a specific membrane is crucial for proper epithelial cell function. KCa3.1, a calcium-activated, intermediate-conductance potassium channel, is targeted to the basolateral membrane (BLM) in epithelial cells. Surprisingly, the mechanism of KCa3.1 membrane targeting is poorly understood. We previously reported that targeting of KCa3.1 to the BLM of epithelial cells is Myosin-Vc-, Rab1-and Rab8-dependent. Here, we examine the role of the SNARE proteins VAMP3, SNAP-23 and syntaxin 4 (STX-4) in the targeting of KCa3.1 to the BLM of Fischer rat thyroid (FRT) epithelial cells. We carried out immunoblot, siRNA and Ussing chamber experiments on FRT cells, stably expressing KCa3.1-BLAP/Bir-A-KDEL, grown as high-resistance monolayers. siRNA-mediated knockdown of VAMP3 reduced BLM expression of KCa3.1 by 57 ± 5% (p ≤ 0.05, n = 5). Measurements of BLM-localized KCa3.1 currents, in Ussing chambers, demonstrated knockdown of VAMP3 reduced KCa3.1 current by 70 ± 4% (p ≤ 0.05, n = 5). Similarly, siRNA knockdown of SNAP-23 reduced the expression of KCa3.1 at the BLM by 56 ± 7% (p ≤ 0.01, n = 6) and reduced KCa3.1 current by 80 ± 11% (p ≤ 0.05, n = 6). Also, knockdown of STX-4 lowered the BLM expression of KCa3.1 by 54 ± 6% (p ≤ 0.05, n = 5) and reduced KCa3.1 current by 78 ± 11% (p ≤ 0.05, n = 5). Finally, co-immunoprecipitation experiments demonstrated associations between KCa3.1, VAMP3, SNAP-23 and STX-4. These data indicate that VAMP3, SNAP-23 and STX-4 are critical for the targeting KCa3.1 to BLM of polarized epithelial cells.
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Affiliation(s)
- Rachel E. Farquhar
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Tanya T. Cheung
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Matthew J. E. Logue
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Fiona J. McDonald
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Daniel C. Devor
- Department of Cell Biology, University of Pittsburgh, School of Medicine, Pittsburgh, PA, United States
| | - Kirk L. Hamilton
- Department of Physiology, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- *Correspondence: Kirk L. Hamilton,
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Philp AR, Miranda F, Gianotti A, Mansilla A, Scudieri P, Musante I, Vega G, Figueroa CD, Galietta LJV, Sarmiento JM, Flores CA. KCa3.1 differentially regulates trachea and bronchi epithelial gene expression in a chronic-asthma mouse model. Physiol Genomics 2022; 54:273-282. [PMID: 35658672 DOI: 10.1152/physiolgenomics.00134.2021] [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: 11/22/2022] Open
Abstract
Ion channels are potentially exploitable as pharmacological targets to treat asthma. This study evaluated the role of KCa3.1 channels, encoded by Kcnn4, in regulating the gene expression of mouse airway epithelium and the development of asthma traits. We used the ovalbumin (OVA) challenge as an asthma model in wild type and Kcnn4-/- mice, performed histological analysis, and measured serum IgE to evaluate asthma traits. We analyzed gene expression of isolated epithelial cells of trachea or bronchi using mRNA sequencing and gene ontology and performed Ussing chamber experiments in mouse trachea to evaluate anion secretion. Gene expression of epithelial cells from mouse airways differed between trachea and bronchi, indicating regional differences in the inflammatory and transepithelial transport properties of proximal and distal airways. We found that Kcnn4 silencing reduced mast cell numbers, mucus, and collagen in the airways, and reduced the amount of epithelial anion secretion in the OVA-challenged animals. Additionally, gene expression was differentially modified in the trachea and bronchi, with Kcnn4 genetic silencing significantly altering the expression of genes involved in the TNF pathway, supporting the potential of KCa3.1 as a therapeutic target for asthma.
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Affiliation(s)
- Amber R Philp
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile.,Austral University of Chile, Valdivia, Chile
| | - Fernando Miranda
- Departamento de Fisiología, Austral University of Chile, Valdivia, Chile
| | | | - Agustín Mansilla
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile.,Austral University of Chile, Valdivia, Chile
| | | | | | - Génesis Vega
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile
| | | | - Luis J V Galietta
- TIGEM, Pozzuoli, Italia.,Department of Translational Medical Sciences, University of Naples Federico II, Naples, Italy
| | - José M Sarmiento
- Departamento de Fisiología, Austral University of Chile, Valdivia, Chile
| | - Carlos A Flores
- Centro de Estudios Científicos, Valdivia, Los Rios, Chile.,Universidad San Sebastián, Valdivia, Chile
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6
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Brömmel K, Konken CP, Börgel F, Obeng-Darko H, Schelhaas S, Bulk E, Budde T, Schwab A, Schäfers M, Wünsch B. Synthesis and biological evaluation of PET tracers designed for imaging of calcium activated potassium channel 3.1 (K Ca3.1) channels in vivo. RSC Adv 2021; 11:30295-30304. [PMID: 35480282 PMCID: PMC9041111 DOI: 10.1039/d1ra03850h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Accepted: 09/05/2021] [Indexed: 12/14/2022] Open
Abstract
Expression of the Ca2+ activated potassium channel 3.1 (KCa3.1) channel (also known as the Gàrdos channel) is dysregulated in many tumor entities and has predictive power with respect to patient survival. Therefore, a positron emission tomography (PET) tracer targeting this ion channel could serve as a potential diagnostic tool by imaging the KCa3.1 channel in vivo. It was envisaged to synthesize [18F]senicapoc ([18F]1) since senicapoc (1) shows high affinity and excellent selectivity towards the KCa3.1 channels. Because problems occurred during 18F-fluorination, the [18F]fluoroethoxy senicapoc derivative [18F]28 was synthesized to generate an alternative PET tracer targeting the KCa3.1 channel. Inhibition of the KCa3.1 channel by 28 was confirmed by patch clamp experiments. In vitro stability in mouse and human serum was shown for 28. Furthermore, biodistribution experiments in wild type mice were performed. Since [18F]fluoride was detected in vivo after application of [18F]28, an in vitro metabolism study was conducted. A potential degradation route of fluoroethoxy derivatives in vivo was found which in general should be taken into account when designing new PET tracers for different targets with a [18F]fluoroethoxy moiety as well as when using the popular prosthetic group [18F]fluoroethyl tosylate for the alkylation of phenols. Expression of the Ca2+ activated potassium channel 3.1 (KCa3.1) channel (also known as the Gàrdos channel) is dysregulated in many tumor entities and has predictive power with respect to patient survival.![]()
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Affiliation(s)
- Kathrin Brömmel
- Institute for Pharmaceutical and Medicinal Chemistry, Westphalian Wilhelms-University Münster Corrensstraße 48 D-48149 Münster Germany
| | - Christian Paul Konken
- Department of Nuclear Medicine, University Hospital Münster, Albert-Schweitzer-Campus 1 Building A1 D-48149 Münster Germany +49-8347363 +49-251-8344791
| | - Frederik Börgel
- Institute for Pharmaceutical and Medicinal Chemistry, Westphalian Wilhelms-University Münster Corrensstraße 48 D-48149 Münster Germany
| | - Henry Obeng-Darko
- Institute for Pharmaceutical and Medicinal Chemistry, Westphalian Wilhelms-University Münster Corrensstraße 48 D-48149 Münster Germany
| | - Sonja Schelhaas
- European Institute for Molecular Imaging (EIMI), Westphalian Wilhelms-University Münster Waldeyerstraße 15 D-48149 Münster Germany
| | - Etmar Bulk
- Institute for Physiology II, University Hospital Münster Robert-Koch-Straße 27b D-48149 Münster Germany
| | - Thomas Budde
- Institute for Physiology I, University Hospital Münster Robert-Koch-Straße 27a D-48149 Münster Germany.,Cells-in-Motion Interfaculty Center, Westphalian Wilhelms-University Münster Waldeyerstraße 15 D-84149 Münster Germany
| | - Albrecht Schwab
- Institute for Physiology II, University Hospital Münster Robert-Koch-Straße 27b D-48149 Münster Germany.,Cells-in-Motion Interfaculty Center, Westphalian Wilhelms-University Münster Waldeyerstraße 15 D-84149 Münster Germany
| | - Michael Schäfers
- Department of Nuclear Medicine, University Hospital Münster, Albert-Schweitzer-Campus 1 Building A1 D-48149 Münster Germany +49-8347363 +49-251-8344791.,European Institute for Molecular Imaging (EIMI), Westphalian Wilhelms-University Münster Waldeyerstraße 15 D-48149 Münster Germany.,Cells-in-Motion Interfaculty Center, Westphalian Wilhelms-University Münster Waldeyerstraße 15 D-84149 Münster Germany
| | - Bernhard Wünsch
- Institute for Pharmaceutical and Medicinal Chemistry, Westphalian Wilhelms-University Münster Corrensstraße 48 D-48149 Münster Germany.,Cells-in-Motion Interfaculty Center, Westphalian Wilhelms-University Münster Waldeyerstraße 15 D-84149 Münster Germany
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7
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Roach KM, Bradding P. Ca 2+ signalling in fibroblasts and the therapeutic potential of K Ca3.1 channel blockers in fibrotic diseases. Br J Pharmacol 2020; 177:1003-1024. [PMID: 31758702 DOI: 10.1111/bph.14939] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 10/23/2019] [Accepted: 11/13/2019] [Indexed: 12/13/2022] Open
Abstract
The role of Ca2+ signalling in fibroblasts is of great interest in fibrosis-related diseases. Intracellular free Ca2+ ([Ca2+ ]i ) is a ubiquitous secondary messenger, regulating a number of cellular functions such as secretion, metabolism, differentiation, proliferation and contraction. The intermediate conductance Ca2+ -activated K+ channel KCa 3.1 is pivotal in Ca2+ signalling and plays a central role in fibroblast processes including cell activation, migration and proliferation through the regulation of cell membrane potential. Evidence from a number of approaches demonstrates that KCa 3.1 plays an important role in the development of many fibrotic diseases, including idiopathic pulmonary, renal tubulointerstitial fibrosis and cardiovascular disease. The KCa 3.1 selective blocker senicapoc was well tolerated in clinical trials for sickle cell disease, raising the possibility of rapid translation to the clinic for people suffering from pathological fibrosis. This review after analysing all the data, concludes that targeting KCa 3.1 should be a high priority for human fibrotic disease.
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Affiliation(s)
- Katy M Roach
- Institute for Lung Health, Department of Respiratory Sciences, University of Leicester, Leicester, UK
| | - Peter Bradding
- Institute for Lung Health, Department of Respiratory Sciences, University of Leicester, Leicester, UK
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Hynes D, Harvey BJ. Dexamethasone reduces airway epithelial Cl - secretion by rapid non-genomic inhibition of KCNQ1, KCNN4 and KATP K + channels. Steroids 2019; 151:108459. [PMID: 31330137 DOI: 10.1016/j.steroids.2019.108459] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 07/05/2019] [Accepted: 07/07/2019] [Indexed: 11/26/2022]
Abstract
Basolateral membrane K+ channels play a key role in basal and agonist stimulated Cl- transport across airway epithelial cells by generating a favourable electrical driving force for Cl- efflux. The K+ channel sub-types and molecular mechanisms of regulation by hormones and secretagoues are still poorly understood. Here we have identified the type of K+ channels involved in cAMP and Ca2+ stimulated Cl- secretion and uncovered a novel anti-secretory effect of dexamethasone mediated by inhibition of basolateral membrane K+ channels in a human airway cell model of 16HBE14o- cells commonly used for ion transport studies. Dexamethasone produced a rapid inhibition of transepithelial chloride ion secretion under steady state conditions and after stimulation with cAMP agonist (forskolin) or a Ca2+ mobilizing agonist (ATP). Our results show three different types of K+ channels are targeted by dexamethasone to reduce airway secretion, namely Ca2+-activated secretion via KCNN4 (KCa3.1) channels and cAMP-activated secretion via KCNQ1 (Kv7.1) and KATP (Kir6.1,6.2) channels. The down-regulation of KCNN4 and KCNQ1 channel activities by dexamethasone involves rapid non-genomic activation of PKCα and PKA signalling pathways, respectively. Dexamethasone signal transduction for PKC and PKA activation was demonstrated to occur through a rapid non-genomic pathway that did not implicate the classical nuclear receptors for glucocorticoids or mineralocorticoids but occurred via a novel signalling cascade involving sequentially a Gi-protein coupled receptor, PKC, adenylyl cyclase Type IV, cAMP, PKA and ERK1/2 activation. The rapid, non-genomic, effects of dexamethasone on airway epithelial ion transport and cell signalling introduces a new paradigm for glucocorticoid actions in lung epithelia which may serve to augment the anti-inflammatory activity of the steroid and enhance its therapeutic potential in treating airway hypersecretion in asthma and COPD.
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Affiliation(s)
- Darina Hynes
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland
| | - Brian J Harvey
- Department of Molecular Medicine, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin 9, Ireland; Centro di Estudios Cientificos CECs, Valdivia, Chile.
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9
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Mei Y, Fang C, Ding S, Liu X, Hu J, Xu J, Mei Q. PAP-1 ameliorates DSS-induced colitis with involvement of NLRP3 inflammasome pathway. Int Immunopharmacol 2019; 75:105776. [DOI: 10.1016/j.intimp.2019.105776] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/11/2019] [Accepted: 07/19/2019] [Indexed: 02/07/2023]
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10
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Oakes V, Domene C. Capturing the Molecular Mechanism of Anesthetic Action by Simulation Methods. Chem Rev 2018; 119:5998-6014. [DOI: 10.1021/acs.chemrev.8b00366] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Victoria Oakes
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
| | - Carmen Domene
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom
- Department of Chemistry, University of Oxford, Oxford OX1 3TA, United Kingdom
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11
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Huang C, Zhang L, Shi Y, Yi H, Zhao Y, Chen J, Pollock CA, Chen XM. The KCa3.1 blocker TRAM34 reverses renal damage in a mouse model of established diabetic nephropathy. PLoS One 2018; 13:e0192800. [PMID: 29425253 PMCID: PMC5806905 DOI: 10.1371/journal.pone.0192800] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 01/30/2018] [Indexed: 01/26/2023] Open
Abstract
Despite optimal control of hyperglycaemia, hypertension, and dyslipidaemia, the number of patients with diabetic nephropathy (DN) continues to grow. Strategies to target various signaling pathways to prevent DN have been intensively investigated in animal models and many have been proved to be promising. However, targeting these pathways once kidney disease is established, remain unsatisfactory. The clinical scenario is that patients with diabetes mellitus often present with established kidney damage and need effective treatments to repair and reverse the kidney damage. In this studies, eNOS-/- mice were administered with streptozotocin to induce diabetes. At 24 weeks, at which time we have previously demonstrated albuminuria and pathological changes of diabetic nephropathy, mice were randomised to receive TRAM34 subcutaneously, a highly selective inhibitor of potassium channel KCa3.1 or DMSO (vehicle) for a further 14 weeks. Albuminuria was assessed, inflammatory markers (CD68, F4/80) and extracellular matrix deposition (type I collagen and fibronectin) in the kidneys were examined. The results clearly demonstrate that TRAM34 reduced albuminuria, decreased inflammatory markers and reversed extracellular matrix deposition in kidneys via inhibition of the TGF-β1 signaling pathway. These results indicate that KCa3.1 blockade effectively reverses established diabetic nephropathy in this rodent model and provides a basis for progressing to human studies.
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Affiliation(s)
- Chunling Huang
- Kolling Institute, Sydney Medical School-Northern, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Ling Zhang
- School of Pharmaceutical Science &Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kuming, China
| | - Ying Shi
- Kolling Institute, Sydney Medical School-Northern, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Hao Yi
- Kolling Institute, Sydney Medical School-Northern, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Yongli Zhao
- Department of Pediatrics, the Second Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Jason Chen
- Department of Anatomical Pathology, Royal North Shore Hospital, St Leonards, Sydney, New South Wales, Australia
| | - Carol A. Pollock
- Kolling Institute, Sydney Medical School-Northern, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales, Australia
| | - Xin-Ming Chen
- Kolling Institute, Sydney Medical School-Northern, University of Sydney, Royal North Shore Hospital, St Leonards, New South Wales, Australia
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12
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Mathew John C, Khaddaj Mallat R, George G, Kim T, Mishra RC, Braun AP. Pharmacologic targeting of endothelial Ca 2+-activated K + channels: A strategy to improve cardiovascular function. Channels (Austin) 2018; 12:126-136. [PMID: 29577810 PMCID: PMC5972810 DOI: 10.1080/19336950.2018.1454814] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 03/15/2018] [Indexed: 12/17/2022] Open
Abstract
Endothelial small and intermediate-conductance, Ca2+-activated K+ channels (KCa2.3 and KCa3.1, respectively) play an important role in the regulation of vascular function and systemic blood pressure. Growing evidence indicates that they are intimately involved in agonist-evoked vasodilation of small resistance arteries throughout the circulation. Small molecule activators of KCa2.x and 3.1 channels, such as SKA-31, can acutely inhibit myogenic tone in isolated resistance arteries, induce effective vasodilation in intact vascular beds, such as the coronary circulation, and acutely decrease systemic blood pressure in vivo. The blood pressure-lowering effect of SKA-31, and early indications of improvement in endothelial dysfunction suggest that endothelial KCa channel activators could eventually be developed into a new class of endothelial targeted agents to combat hypertension or atherosclerosis. This review summarises recent insights into the activation of endothelial Ca2+ activated K+ channels in various vascular beds, and how tools, such as SKA-31, may be beneficial in disease-related conditions.
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Affiliation(s)
- Cini Mathew John
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Rayan Khaddaj Mallat
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Grace George
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Taeyeob Kim
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ramesh C. Mishra
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Andrew P. Braun
- Department of Physiology and Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
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13
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Hartmann AK, Aranda Lopez P, Zajac M, Freichel M, Schild H, Radsak MP, Stassen M. 9-Phenanthrol enhances the generation of an CD8 + T cell response following transcutaneous immunization with imiquimod in mice. J Dermatol Sci 2017; 87:260-267. [PMID: 28823644 DOI: 10.1016/j.jdermsci.2017.07.018] [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: 07/07/2017] [Accepted: 07/14/2017] [Indexed: 10/19/2022]
Abstract
BACKGROUND Transcutaneous immunization (TCI) is a non-invasive vaccination strategy targeting the skin-associated lymphoid tissue. Topical application of the TLR7 agonist imiquimod as adjuvant in combination with peptide antigens activates the innate immune system and mounts cytotoxic T lymphocyte (CTL) responses. OBJECTIVE Based on the commercial 5% imiquimod-containing drug Aldara we aimed to develop an improved formulation with superior vaccination efficiencies. The primary target was the enhancement of mast cell activation as important key for the function of the innate immune system. METHODS We investigated the effects of 9-phenanthrol (9-phe) on the activation of mast cells in vitro and in vivo. For TCI, we applied 0.2% 9-phe in Aldara or Aldara alone as adjuvants in combination with the MHC class I - restricted peptide SIINFEKL. To monitor vaccination, mast cell degranulation, migration of DC and frequencies of epitope-specific CTL was assessed. In a transgenic tumor model, the efficiencies of prophylactic immunization against a tumor antigen were also monitored. RESULTS 9-phe induced degranulation of mast cells in vitro and upon topical application in vivo. A mixture of 0.2% 9-phe in Aldara showed superior results regarding the migration of DC and the expansion of antigen-specific CTL. Consequently, prophylactic immunization with 0.2% 9-phe in Aldara caused enhanced protection against tumor inoculation. CONCLUSION Our data demonstrate that a simple modification of an adjuvant formulation can yield superior results in experimental vaccination protocols by boosting critical steps leading to the generation of an efficient CTL response.
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Affiliation(s)
- Ann-Kathrin Hartmann
- Institute for Immunology, University Medical Center, Johannes Gutenberg University, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Pamela Aranda Lopez
- 3rd Dept. of Medicine, University Medical Center, Johannes Gutenberg University, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Marek Zajac
- Institute for Immunology, University Medical Center, Johannes Gutenberg University, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Marc Freichel
- Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Hansjörg Schild
- Institute for Immunology, University Medical Center, Johannes Gutenberg University, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Markus P Radsak
- Institute of Pharmacology, Heidelberg University, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany
| | - Michael Stassen
- Institute for Immunology, University Medical Center, Johannes Gutenberg University, Langenbeckstr. 1, 55131 Mainz, Germany.
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14
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Farquhar RE, Rodrigues E, Hamilton KL. The Role of the Cytoskeleton and Myosin-Vc in the Targeting of KCa3.1 to the Basolateral Membrane of Polarized Epithelial Cells. Front Physiol 2017; 7:639. [PMID: 28101059 PMCID: PMC5209343 DOI: 10.3389/fphys.2016.00639] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 12/06/2016] [Indexed: 12/27/2022] Open
Abstract
Understanding the targeting of KCa3.1 to the basolateral membrane (BLM) of polarized epithelial cells is still emerging. Here, we examined the role of the cytoskeleton (microtubules and microfilaments) and Myosin-Vc (Myo-Vc) in the targeting of KCa3.1 in Fischer rat thyroid epithelial cells. We used a pharmacological approach with immunoblot (for the BLM expression of KCa3.1), Ussing chamber (functional BLM expression of KCa3.1) and siRNA experiments. The actin cytoskeleton inhibitors cytochalasin D (10 μM, 5 h) and latrunculin A (10 μM, 5 h) reduced the targeting of KCa3.1 to the BLM by 88 ± 4 and 70 ± 5%, respectively. Colchicine (10 μM, 5 h) a microtubule inhibitor reduced targeting of KCa3.1 to the BLM by 63 ± 7% and decreased 1-EBIO-stimulated KCa3.1 K+ current by 46 ± 18%, compared with control cells. ML9 (10 μM, 5 h), an inhibitor of myosin light chain kinase, decreased targeting of the channel by 83 ± 2% and reduced K+ current by 54 ± 8% compared to control cells. Inhibiting Myo-V with 2,3-butanedione monoxime (10 mM, 5 h) reduced targeting of the channel to the BLM by 58 ± 5% and decreased the stimulated current of KCa3.1 by 48 ± 12% compared with control cells. Finally, using siRNA for Myo-Vc, we demonstrated that knockdown of Myo-Vc reduced the BLM expression of KCa3.1 by 44 ± 7% and KCa3.1 K+ current by 1.04 ± 0.14 μA compared with control cells. These data suggest that the microtubule and microfilament cytoskeleton and Myo-Vc are critical for the targeting of KCa3.1.
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Affiliation(s)
- Rachel E Farquhar
- Department of Physiology, Otago School of Medical Sciences, University of Otago Dunedin, New Zealand
| | - Ely Rodrigues
- Department of Medicine, Otago School of Medical Sciences, University of Otago Dunedin, New Zealand
| | - Kirk L Hamilton
- Department of Physiology, Otago School of Medical Sciences, University of Otago Dunedin, New Zealand
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15
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Design and characterization of novel all-solid-state potentiometric sensor array dedicated to physiological measurements. Talanta 2016; 159:7-13. [DOI: 10.1016/j.talanta.2016.06.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 05/30/2016] [Accepted: 06/01/2016] [Indexed: 12/25/2022]
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16
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Singh J, Shah R, Singh D. Inundation of asthma target research: Untangling asthma riddles. Pulm Pharmacol Ther 2016; 41:60-85. [PMID: 27667568 DOI: 10.1016/j.pupt.2016.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/11/2016] [Accepted: 09/20/2016] [Indexed: 12/31/2022]
Abstract
Asthma is an inveterate inflammatory disorder, delineated by the airway inflammation, bronchial hyperresponsiveness (BHR) and airway wall remodeling. Although, asthma is a vague term, and is recognized as heterogenous entity encompassing different phenotypes. Targeting single mediator or receptor did not prove much clinical significant, as asthma is complex disease involving myriad inflammatory mediators. Asthma may probably involve a large number of different types of molecular and cellular components interacting through complex pathophysiological pathways. This review covers the past, present, and future therapeutic approaches and pathophysiological mechanisms of asthma. Furthermore, review describe importance of targeting several mediators/modulators and receptor antagonists involved in the physiopathology of asthma. Novel targets for asthma research include Galectins, Immunological targets, K + Channels, Kinases and Transcription Factors, Toll-like receptors, Selectins and Transient receptor potential channels. But recent developments in asthma research are very promising, these include Bitter taste receptors (TAS2R) abated airway obstruction in mouse model of asthma and Calcium-sensing receptor obliterate inflammation and in bronchial hyperresponsiveness allergic asthma. All these progresses in asthma targets, and asthma phenotypes exploration are auspicious in untangling of asthma riddles.
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Affiliation(s)
- Jatinder Singh
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, 147002, Punjab, India
| | - Ramanpreet Shah
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, 147002, Punjab, India
| | - Dhandeep Singh
- Department of Pharmaceutical Sciences and Drug Research, Punjabi University, Patiala, 147002, Punjab, India.
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17
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Chachi L, Gavrila A, Tliba O, Amrani Y. Abnormal corticosteroid signalling in airway smooth muscle: mechanisms and perspectives for the treatment of severe asthma. Clin Exp Allergy 2016; 45:1637-46. [PMID: 26017278 DOI: 10.1111/cea.12577] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Growing in vivo evidence supports the concept that airway smooth muscle produces various immunomodulatory factors that could contribute to asthma pathogenesis via the regulation of airway inflammation, airway narrowing and remodelling. Targeting ASM using bronchial thermoplasty has provided undeniable clinical benefits for patients with uncontrolled severe asthma who are refractory to glucocorticoid therapy. The present review will explain why the failure of glucocorticoids to adequately manage patients with severe asthma could derive from their inability to affect the immunomodulatory potential of ASM. We will support the view that ASM sensitivity to glucocorticoid therapy can be blunted in severe asthma and will describe some of the factors and mechanisms that could be responsible for glucocorticoid insensitivity.
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Affiliation(s)
- L Chachi
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
| | - A Gavrila
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
| | - O Tliba
- Department of Pharmaceutical Sciences, Thomas Jefferson University, Jefferson School of Pharmacy, Philadelphia, PA, USA
| | - Y Amrani
- Department of Infection, Immunity and Inflammation, University of Leicester, Leicester, UK
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18
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Yi M, Dou F, Lu Q, Yu Z, Chen H. Activation of the KCa3.1 channel contributes to traumatic scratch injury-induced reactive astrogliosis through the JNK/c-Jun signaling pathway. Neurosci Lett 2016; 624:62-71. [DOI: 10.1016/j.neulet.2016.05.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 04/26/2016] [Accepted: 05/03/2016] [Indexed: 11/30/2022]
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19
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RamaKrishnan AM, Sankaranarayanan K. Understanding autoimmunity: The ion channel perspective. Autoimmun Rev 2016; 15:585-620. [PMID: 26854401 DOI: 10.1016/j.autrev.2016.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Accepted: 01/29/2016] [Indexed: 12/11/2022]
Abstract
Ion channels are integral membrane proteins that orchestrate the passage of ions across the cell membrane and thus regulate various key physiological processes of the living system. The stringently regulated expression and function of these channels hold a pivotal role in the development and execution of various cellular functions. Malfunction of these channels results in debilitating diseases collectively termed channelopathies. In this review, we highlight the role of these proteins in the immune system with special emphasis on the development of autoimmunity. The role of ion channels in various autoimmune diseases is also listed out. This comprehensive review summarizes the ion channels that could be used as molecular targets in the development of new therapeutics against autoimmune disorders.
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Affiliation(s)
| | - Kavitha Sankaranarayanan
- AU-KBC Research Centre, Madras Institute of Technology, Anna University, Chrompet, Chennai 600 044, India.
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20
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Kuzmenkov AI, Grishin EV, Vassilevski AA. Diversity of Potassium Channel Ligands: Focus on Scorpion Toxins. BIOCHEMISTRY (MOSCOW) 2016; 80:1764-99. [DOI: 10.1134/s0006297915130118] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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21
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Arthur GK, Duffy SM, Roach KM, Hirst RA, Shikotra A, Gaillard EA, Bradding P. KCa3.1 K+ Channel Expression and Function in Human Bronchial Epithelial Cells. PLoS One 2015; 10:e0145259. [PMID: 26689552 PMCID: PMC4687003 DOI: 10.1371/journal.pone.0145259] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 11/30/2015] [Indexed: 12/13/2022] Open
Abstract
The KCa3.1 K+ channel has been proposed as a novel target for pulmonary diseases such as asthma and pulmonary fibrosis. It is expressed in epithelia but its expression and function in primary human bronchial epithelial cells (HBECs) has not been described. Due to its proposed roles in the regulation of cell proliferation, migration, and epithelial fluid secretion, inhibiting this channel might have either beneficial or adverse effects on HBEC function. The aim of this study was to assess whether primary HBECs express the KCa3.1 channel and its role in HBEC function. Primary HBECs from the airways of healthy and asthmatic subjects, SV-transformed BEAS-2B cells and the neoplastic H292 epithelial cell line were studied. Primary HBECs, BEAS-2B and H292 cells expressed KCa3.1 mRNA and protein, and robust KCa3.1 ion currents. KCa3.1 protein expression was increased in asthmatic compared to healthy airway epithelium in situ, and KCa3.1 currents were larger in asthmatic compared to healthy HBECs cultured in vitro. Selective KCa3.1 blockers (TRAM-34, ICA-17043) had no effect on epithelial cell proliferation, wound closure, ciliary beat frequency, or mucus secretion. However, several features of TGFβ1-dependent epithelial-mesenchymal transition (EMT) were inhibited by KCa3.1 blockade. Treatment with KCa3.1 blockers is likely to be safe with respect to airway epithelial biology, and may potentially inhibit airway remodelling through the inhibition of EMT.
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Affiliation(s)
- Greer K. Arthur
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
- * E-mail:
| | - S. Mark Duffy
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
| | - Katy M. Roach
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
| | - Rob A. Hirst
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
| | - Aarti Shikotra
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
| | - Erol A. Gaillard
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
| | - Peter Bradding
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
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22
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Hakim MA, Yang S, Lai R. Centipede venoms and their components: resources for potential therapeutic applications. Toxins (Basel) 2015; 7:4832-51. [PMID: 26593947 PMCID: PMC4663536 DOI: 10.3390/toxins7114832] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 11/10/2015] [Accepted: 11/11/2015] [Indexed: 12/23/2022] Open
Abstract
Venomous animals have evolved with sophisticated bio-chemical strategies to arrest prey and defend themselves from natural predators. In recent years, peptide toxins from venomous animals have drawn considerable attention from researchers due to their surprising chemical, biochemical, and pharmacological diversity. Similar to other venomous animals, centipedes are one of the crucial venomous arthropods that have been used in traditional medicine for hundreds of years in China. Despite signifying pharmacological importance, very little is known about the active components of centipede venoms. More than 500 peptide sequences have been reported in centipede venomous glands by transcriptome analysis, but only a small number of peptide toxins from centipede has been functionally described. Like other venomous animals such as snakes, scorpions, and spiders, the venom of centipedes could be an excellent source of peptides for developing drugs for treatments as well as bio-insecticides for agrochemical applications. Although centipede venoms are yet to be adequately studied, the venom of centipedes as well as their components described to date, should be compiled to help further research. Therefore, based on previous reports, this review focusses on findings and possible therapeutic applications of centipede venoms as well as their components.
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Affiliation(s)
- Md Abdul Hakim
- Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of sciences, Kunming 650223, Yunnan, China.
- University of Chinese Academy of Sciences, Beijing100009, China.
| | - Shilong Yang
- Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of sciences, Kunming 650223, Yunnan, China.
- University of Chinese Academy of Sciences, Beijing100009, China.
| | - Ren Lai
- Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of sciences, Kunming 650223, Yunnan, China.
- Joint Laboratory of Natural Peptide, University of Science and Technology of China and Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China.
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Abstract
Tityus serrulatus (Ts) is the main scorpion species of medical importance in Brazil. Ts venom is composed of several compounds such as mucus, inorganic salts, lipids, amines, nucleotides, enzymes, kallikrein inhibitor, natriuretic peptide, proteins with high molecular mass, peptides, free amino acids and neurotoxins. Neurotoxins are considered the most responsible for the envenoming syndrome due to their pharmacological action on ion channels such as voltage-gated sodium (Nav) and potassium (Kv) channels. The major goal of this review is to present important advances in Ts envenoming research, correlating both the crude Ts venom and isolated toxins with alterations observed in all human systems. The most remarkable event lies in the Ts induced massive releasing of neurotransmitters influencing, directly or indirectly, the entire body. Ts venom proved to extremely affect nervous and muscular systems, to modulate the immune system, to induce cardiac disorders, to cause pulmonary edema, to decrease urinary flow and to alter endocrine, exocrine, reproductive, integumentary, skeletal and digestive functions. Therefore, Ts venom possesses toxins affecting all anatomic systems, making it a lethal cocktail. However, its low lethality may be due to the low venom mass injected, to the different venom compositions, the body characteristics and health conditions of the victim and the local of Ts sting. Furthermore, we also described the different treatments employed during envenoming cases. In particular, throughout the review, an effort will be made to provide information from an extensive documented studies concerning Ts venom in vitro, in animals and in humans (a total of 151 references).
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24
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Zhu H, Yan L, Gu J, Hao W, Cao J. Kv1.3 channel blockade enhances the phagocytic function of RAW264.7 macrophages. SCIENCE CHINA-LIFE SCIENCES 2015; 58:867-75. [PMID: 26354506 DOI: 10.1007/s11427-015-4915-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 06/13/2015] [Indexed: 11/25/2022]
Abstract
This study aimed to comprehend the largely unknown role of voltage-gated potassium channel 1.3 (Kv1.3) in the phagocytic function of macrophages. We found that blocking of the Kv1.3 channel with 100 pmol L(-1) Stichodactyla helianthus neurotoxin (ShK) enhanced the phagocytic capacities of both resting and lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages in the chicken erythrocyte system. In the fluorescein isothiocyanate (FITC)-labeled Escherichia coli k-12 system, ShK increased the phagocytic capacities of resting RAW264.7 cells, but not of the LPS-stimulated cells, as LPS alone stimulated almost saturated phagocytosis of the macrophages. ShK increased the nitric oxide (NO) production in LPS-activated cells, but not in resting RAW264.7 cells. There was no effect of ShK alone on the cytokine secretions in resting RAW264.7 cells, but it suppressed IL-1β secretion in LPS-stimulated RAW264.7 cells. At a concentration of 100 pmol L(-1), ShK did not affect the viability of the tested cells. Kv1.3 was expressed in RAW264.7 cells; this expression was downregulated by LPS, but significantly upregulated by disrupting caveolin-dependent endocytosis with filipin III. In addition, cytochalasin D, an inhibitor of actin polymerization, did not affect the Kv1.3 expression. Thus, blocking of the Kv1.3 channel enhances the phagocytic capacity and NO production of this cell line. Our results suggest that Kv1.3 channel serves as a negative regulator of phagocytosis in macrophages and can therefore be a potential target in the treatment of macrophage dysfunction.
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Affiliation(s)
- Hong Zhu
- Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking, Union Medical College, Beijing, 100005, China
| | - Li Yan
- Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - JingLi Gu
- Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking, Union Medical College, Beijing, 100005, China
| | - Wei Hao
- Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking, Union Medical College, Beijing, 100005, China
| | - JiMin Cao
- Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine Peking, Union Medical College, Beijing, 100005, China.
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25
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Kazama I, Tamada T, Tachi M. Usefulness of targeting lymphocyte Kv1.3-channels in the treatment of respiratory diseases. Inflamm Res 2015. [PMID: 26206235 DOI: 10.1007/s00011-015-0855-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
T lymphocytes predominantly express delayed rectifier K(+)-channels (Kv1.3) in their plasma membranes. Patch-clamp studies revealed that the channels play crucial roles in facilitating the calcium influx necessary to trigger lymphocyte activation and proliferation. Using selective channel inhibitors in experimental animal models, in vivo studies further revealed the clinically relevant relationship between the channel expression and the development of chronic respiratory diseases, in which chronic inflammation or the overstimulation of cellular immunity in the airways is responsible for the pathogenesis. In chronic respiratory diseases, such as chronic obstructive pulmonary disease, asthma, diffuse panbronchiolitis and cystic fibrosis, in addition to the supportive management for the symptoms, the anti-inflammatory effects of macrolide antibiotics were shown to be effective against the over-activation or proliferation of T lymphocytes. Recently, we provided physiological and pharmacological evidence that macrolide antibiotics, together with calcium channel blockers, HMG-CoA reductase inhibitors, and nonsteroidal anti-inflammatory drugs, effectively suppress the Kv1.3-channel currents in lymphocytes, and thus exert anti-inflammatory or immunomodulatory effects. In this review article, based on the findings obtained from recent in vivo and in vitro studies, we address the novel therapeutic implications of targeting the lymphocyte Kv1.3-channels for the treatment of chronic or acute respiratory diseases.
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Affiliation(s)
- Itsuro Kazama
- Department of Physiology I, Tohoku University Graduate School of Medicine, Seiryo-cho, Aoba-ku, Sendai, Miyagi, Japan.
| | - Tsutomu Tamada
- Department of Respiratory Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Masahiro Tachi
- Department of Plastic and Reconstructive Surgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
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26
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Spear JM, Koborssy DA, Schwartz AB, Johnson AJ, Audhya A, Fadool DA, Stagg SM. Kv1.3 contains an alternative C-terminal ER exit motif and is recruited into COPII vesicles by Sec24a. BMC BIOCHEMISTRY 2015; 16:16. [PMID: 26156069 PMCID: PMC4497498 DOI: 10.1186/s12858-015-0045-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/26/2015] [Indexed: 12/11/2022]
Abstract
Background Potassium channels play a fundamental role in resetting the resting membrane potential of excitable cells. Determining the intracellular trafficking and localization mechanisms of potassium channels provides a platform to fully characterize their maturation and functionality. Previous investigations have discovered residues or motifs that exist in their primary structure, which directly promote anterograde trafficking of nascent potassium channels. Recently, a non-conical di-acidic motif (E483/484) has been discovered in the C-terminus of the mammalian homologue of the Shaker voltage-gated potassium channel subfamily member 3 (Kv1.3), and was shown to disrupt the anterograde trafficking of Kv1.3. Results We have further investigated the intracellular trafficking requirements of Kv1.3 both in vivo and in vitro. First, three alternative C-terminal acidic residues, E443, E445, E447 were probed for their involvement within the early secretory pathway of Kv1.3. Single point (E443A, E445A, and E447A) and double point (E443A-E445A, E445A-E447A) mutations exhibited no significant changes in their endoplasmic reticulum (ER) retention. The triple point mutant E443A-E445A-E447A displayed a modest ER retention while deletion of the C-terminus showed dramatic ER retention. Second, we demonstrate in vivo the requirement for the Sec24a isoform to confer anterograde trafficking using a siRNA knockdown assay. Third, we show in vitro the association of recombinantly expressed Kv1.3 and Sec24a proteins. Conclusion These results expand upon previous studies aimed at deciphering the Kv1.3 secretory trafficking mechanisms and further show in vitro evidence of the association between Kv1.3 and the COPII cargo adaptor subunit isoform Sec24a. Electronic supplementary material The online version of this article (doi:10.1186/s12858-015-0045-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John M Spear
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL, 32306, USA.
| | - Dolly Al Koborssy
- Program in Neuroscience, Florida State University, 1107 West Call Street, Tallahassee, FL, 32306, USA.
| | - Austin B Schwartz
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL, 32306, USA.
| | - Adam J Johnson
- Biomolecular Chemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA.
| | - Anjon Audhya
- Biomolecular Chemistry, University of Wisconsin-Madison, 440 Henry Mall, Madison, WI, 53706, USA.
| | - Debra A Fadool
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL, 32306, USA. .,Program in Neuroscience, Florida State University, 1107 West Call Street, Tallahassee, FL, 32306, USA. .,Department of Biological Science, Florida State University, 319 Stadium Drive, Tallahassee, FL, 32306, USA.
| | - Scott M Stagg
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL, 32306, USA. .,Department of Chemistry and Biochemistry, Florida State University, 91 Chieftan Way, Tallahassee, FL, 32306, USA.
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Shao Z, Gaurav R, Agrawal DK. Intermediate-conductance calcium-activated potassium channel KCa3.1 and chloride channel modulate chemokine ligand (CCL19/CCL21)-induced migration of dendritic cells. Transl Res 2015; 166:89-102. [PMID: 25583444 PMCID: PMC4458411 DOI: 10.1016/j.trsl.2014.11.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/31/2014] [Accepted: 11/15/2014] [Indexed: 01/12/2023]
Abstract
The role of ion channels is largely unknown in chemokine-induced migration in nonexcitable cells such as dendritic cells (DCs). Here, we examined the role of intermediate-conductance calcium-activated potassium channel (KCa3.1) and chloride channel (CLC3) in lymphatic chemokine-induced migration of DCs. The amplitude and kinetics of chemokine ligand (CCL19/CCL21)-induced Ca(2+) influx were associated with chemokine receptor 7 expression levels, extracellular-free Ca(2+) and Cl(-), and independent of extracellular K(+). Chemokines (CCL19 and CCL21) and KCa3.1 activator (1-ethyl-1,3-dihydro-2H-benzimidazol-2-one) induced plasma membrane hyperpolarization and K(+) efflux, which was blocked by 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole, suggesting that KCa3.1 carried larger conductance than the inward calcium release-activated calcium channel. Blockade of KCa3.1, low Cl(-) in the medium, and low dose of 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS) impaired CCL19/CCL21-induced Ca(2+) influx, cell volume change, and DC migration. High doses of DIDS completely blocked DC migration possibly by significantly disrupting mitochondrial membrane potential. In conclusion, KCa3.1 and CLC3 are critical in human DC migration by synergistically regulating membrane potential, chemokine-induced Ca(2+) influx, and cell volume.
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Affiliation(s)
- Zhifei Shao
- Center for Clinical and Translational Science, Creighton University of School of Medicine, Omaha, Neb
| | - Rohit Gaurav
- Center for Clinical and Translational Science, Creighton University of School of Medicine, Omaha, Neb
| | - Devendra K Agrawal
- Center for Clinical and Translational Science, Creighton University of School of Medicine, Omaha, Neb.
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Roach KM, Feghali-Bostwick C, Wulff H, Amrani Y, Bradding P. Human lung myofibroblast TGFβ1-dependent Smad2/3 signalling is Ca(2+)-dependent and regulated by KCa3.1 K(+) channels. FIBROGENESIS & TISSUE REPAIR 2015; 8:5. [PMID: 25829947 PMCID: PMC4379608 DOI: 10.1186/s13069-015-0022-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 03/05/2015] [Indexed: 11/10/2022]
Abstract
BACKGROUND Idiopathic pulmonary fibrosis (IPF) is a common and invariably lethal interstitial lung disease with poorly effective therapy. Blockade of the K(+) channel KCa3.1 reduces constitutive α-SMA and Smad2/3 nuclear translocation in IPF-derived human lung myofibroblasts (HLMFs), and inhibits several transforming growth factor beta 1 (TGFβ1)-dependent cell processes. We hypothesized that KCa3.1-dependent cell processes also regulate the TGFβ1-dependent Smad2/3 signalling pathway in HLMFs. HLMFs obtained from non-fibrotic controls (NFC) and IPF lungs were grown in vitro and examined for αSMA expression by immunofluorescence, RT-PCR, and flow cytometry. Two specific and distinct KCa3.1 blockers (TRAM-34 200 nM and ICA-17043 [Senicapoc] 100 nM) were used to determine their effects on TGFβ1-dependent signalling. Expression of phosphorylated and total Smad2/3 following TGFβ1 stimulation was determined by Western blot and Smad2/3 nuclear translocation by immunofluorescence. RESULTS KCa3.1 block attenuated TGFβ1-dependent Smad2/3 phosphorylation and nuclear translocation, and this was mimicked by lowering the extracellular Ca(2+) concentration. KCa3.1 block also inhibited Smad2/3-dependent gene transcription (αSMA, collagen type I), inhibited KCa3.1 mRNA expression, and attenuated TGFβ1-dependent αSMA protein expression. CONCLUSIONS KCa3.1 activity regulates TGFβ1-dependent effects in NFC- and IPF-derived primary HLMFs through the regulation of the TGFβ1/Smad signalling pathway, with promotion of downstream gene transcription and protein expression. KCa3.1 blockers may offer a novel approach to treating IPF.
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Affiliation(s)
- Katy M Roach
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Glenfield Hospital, Groby Road, Leicester, LE3 9QP UK
| | - Carol Feghali-Bostwick
- Department of Medicine, Division of Rheumatology and Immunology, University of South Carolina, Columbia, SC 29208 USA
| | - Heike Wulff
- Department of Pharmacology, University of California, 451 Health Sciences Drive, Davis, CA 95616 USA
| | - Yassine Amrani
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Glenfield Hospital, Groby Road, Leicester, LE3 9QP UK
| | - Peter Bradding
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Glenfield Hospital, Groby Road, Leicester, LE3 9QP UK
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29
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Intermediate conductance, Ca2+-activated K+ channels: a novel target for chronic renal diseases. ACTA ACUST UNITED AC 2014. [DOI: 10.1007/s11515-014-1339-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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30
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Chen R, Gryn’ova G, Wu Y, Coote ML, Chung SH. Mechanisms and Energetics of Potassium Channel Block by Local Anesthetics and Antifungal Agents. Biochemistry 2014; 53:6786-92. [DOI: 10.1021/bi5009408] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
| | | | - Yingliang Wu
- College of Life Sciences, Wuhan University, Wuhan, China
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31
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Garneau L, Klein H, Lavoie MF, Brochiero E, Parent L, Sauvé R. Aromatic-aromatic interactions between residues in KCa3.1 pore helix and S5 transmembrane segment control the channel gating process. ACTA ACUST UNITED AC 2014; 143:289-307. [PMID: 24470490 PMCID: PMC4001770 DOI: 10.1085/jgp.201311097] [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] [Indexed: 11/24/2022]
Abstract
Interactions between aromatic amino acid residues in the pore helix and S5 transmembrane domain control gating of the Ca2+-activated potassium channel KCa3.1. The Ca2+-activated potassium channel KCa3.1 is emerging as a therapeutic target for a large variety of health disorders. One distinguishing feature of KCa3.1 is that the channel open probability at saturating Ca2+ concentrations (Pomax) is low, typically 0.1–0.2 for KCa3.1 wild type. This observation argues for the binding of Ca2+ to the calmodulin (CaM)–KCa3.1 complex, promoting the formation of a preopen closed-state configuration leading to channel opening. We have previously shown that the KCa3.1 active gate is most likely located at the level of the selectivity filter. As Ca2+-dependent gating of KCa3.1 originates from the binding of Ca2+ to CaM in the C terminus, the hypothesis of a gate located at the level of the selectivity filter requires that the conformational change initiated in the C terminus be transmitted to the S5 and S6 transmembrane helices, with a resulting effect on the channel pore helix directly connected to the selectivity filter. A study was thus undertaken to determine to what extent the interactions between the channel pore helix with the S5 and S6 transmembrane segments contribute to KCa3.1 gating. Molecular dynamics simulations first revealed that the largest contact area between the pore helix and the S5 plus S6 transmembrane helices involves residue F248 at the C-terminal end of the pore helix. Unitary current recordings next confirmed that modulating aromatic–aromatic interactions between F248 and W216 of the S5 transmembrane helical segment and/or perturbing the interactions between F248 and residues in S6 surrounding the glycine hinge G274 cause important changes in Pomax. This work thus provides the first evidence for a key contribution of the pore helix in setting Pomax by stabilizing the channel closed configuration through aromatic–aromatic interactions involving F248 of the pore helix. We propose that the interface pore helix/S5 constitutes a promising site for designing KCa3.1 potentiators.
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Affiliation(s)
- Line Garneau
- Department of Physiology and Membrane Protein Research Group, 2 Centre de recherche du Centre hospitalier de l'Université de Montréal, and 3 Department of Medicine, Université de Montréal, Montréal, Quebec H3C 3J7, Canada
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32
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Potassium currents inhibition by gambierol analogs prevents human T lymphocyte activation. Arch Toxicol 2014; 89:1119-34. [DOI: 10.1007/s00204-014-1299-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 06/17/2014] [Indexed: 01/04/2023]
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33
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Yu Z, Yu P, Chen H, Geller HM. Targeted inhibition of KCa3.1 attenuates TGF-β-induced reactive astrogliosis through the Smad2/3 signaling pathway. J Neurochem 2014; 130:41-49. [PMID: 24606313 DOI: 10.1111/jnc.12710] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 02/27/2014] [Accepted: 03/05/2014] [Indexed: 12/16/2022]
Abstract
Reactive astrogliosis, characterized by cellular hypertrophy and various alterations in gene expression and proliferative phenotypes, is considered to contribute to brain injuries and diseases as diverse as trauma, neurodegeneration, and ischemia. KCa3.1 (intermediate-conductance calcium-activated potassium channel), a potassium channel protein, has been reported to be up-regulated in reactive astrocytes after spinal cord injury in vivo. However, little is known regarding the exact role of KCa3.1 in reactive astrogliosis. To elucidate the role of KCa3.1 in regulating reactive astrogliosis, we investigated the effects of either blocking or knockout of KCa3.1 channels on the production of astrogliosis and astrocytic proliferation in response to transforming growth factor (TGF)-β in primary cultures of mouse astrocytes. We found that TGF-β increased KCa3.1 protein expression in astrocytes, with a concomitant marked increase in the expression of reactive astrogliosis, including glial fibrillary acidic protein and chondroitin sulfate proteoglycans. These changes were significantly attenuated by the KCa3.1 inhibitor 1-((2-chlorophenyl) (diphenyl)methyl)-1H-pyrazole (TRAM-34). Similarly, the increase in glial fibrillary acidic protein and chondroitin sulfate proteoglycans in response to TGF-β was attenuated in KCa3.1(-/-) astrocytes. TRAM-34 also suppressed astrocytic proliferation. In addition, the TGF-β-induced phosphorylation of Smad2 and Smad3 proteins was reduced with either inhibition of KCa3.1 with TRAM-34 or in KCa3.1(-/-) astrocytes. These findings highlight a novel role for the KCa3.1 channel in reactive astrogliosis phenotypic modulation and provide a potential target for therapeutic intervention for brain injuries. Reactive astrogliosis is characterized by the expression of glial fibrillary acidic protein and chondroitin sulfate proteoglycans. We demonstrate that either pharmacological blockade or knockout of KCa3.1 channels reduces reactive gliosis in cultured astrocytes caused by TGF-β, and also reduces TGF-β-induced phosphorylation of Smad2/3.
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Affiliation(s)
- Zhihua Yu
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China.,Developmental Neurobiology Section, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Panpan Yu
- Developmental Neurobiology Section, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Hongzhuan Chen
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Herbert M Geller
- Developmental Neurobiology Section, Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
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Koshy S, Huq R, Tanner MR, Atik MA, Porter PC, Khan FS, Pennington MW, Hanania NA, Corry DB, Beeton C. Blocking KV1.3 channels inhibits Th2 lymphocyte function and treats a rat model of asthma. J Biol Chem 2014; 289:12623-32. [PMID: 24644290 DOI: 10.1074/jbc.m113.517037] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Allergic asthma is a chronic inflammatory disease of the airways. Of the different lower airway-infiltrating immune cells that participate in asthma, T lymphocytes that produce Th2 cytokines play important roles in pathogenesis. These T cells are mainly fully differentiated CCR7(-) effector memory T (TEM) cells. Targeting TEM cells without affecting CCR7(+) naïve and central memory (TCM) cells has the potential of treating TEM-mediated diseases, such as asthma, without inducing generalized immunosuppression. The voltage-gated KV1.3 potassium channel is a target for preferential inhibition of TEM cells. Here, we investigated the effects of ShK-186, a selective KV1.3 channel blocker, for the treatment of asthma. A significant proportion of T lymphocytes in the lower airways of subjects with asthma expressed high levels of KV1.3 channels. ShK-186 inhibited the allergen-induced activation of peripheral blood T cells from those subjects. Immunization of F344 rats against ovalbumin followed by intranasal challenges with ovalbumin induced airway hyper-reactivity, which was reduced by the administration of ShK-186. ShK-186 also reduced total immune infiltrates in the bronchoalveolar lavage and number of infiltrating lymphocytes, eosinophils, and neutrophils assessed by differential counts. Rats with the ovalbumin-induced model of asthma had elevated levels of the Th2 cytokines IL-4, IL-5, and IL-13 measured by ELISA in their bronchoalveolar lavage fluids. ShK-186 administration reduced levels of IL-4 and IL-5 and induced an increase in the production of IL-10. Finally, ShK-186 inhibited the proliferation of lung-infiltrating ovalbumin-specific T cells. Our results suggest that KV1.3 channels represent effective targets for the treatment of allergic asthma.
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Affiliation(s)
- Shyny Koshy
- From the Department of Molecular Physiology and Biophysics
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35
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Sequential breakdown of 3-phosphorylated phosphoinositides is essential for the completion of macropinocytosis. Proc Natl Acad Sci U S A 2014; 111:E978-87. [PMID: 24591580 DOI: 10.1073/pnas.1311029111] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Macropinocytosis is a highly conserved endocytic process by which extracellular fluid and solutes are internalized into cells. Macropinocytosis starts with the formation of membrane ruffles at the plasma membrane and ends with their closure. The transient and sequential emergence of phosphoinositides PI(3,4,5)P3 and PI(3,4)P2 in the membrane ruffles is essential for macropinocytosis. By making use of information in the Caenorhabditis elegans mutants defective in fluid-phase endocytosis, we found that mammalian phosphoinositide phosphatase MTMR6 that dephosphorylates PI(3)P to PI, and its binding partner MTMR9, are required for macropinocytosis. INPP4B, which dephosphorylates PI(3,4)P2 to PI(3)P, was also found to be essential for macropinocytosis. These phosphatases operate after the formation of membrane ruffles to complete macropinocytosis. Finally, we showed that KCa3.1, a Ca(2+)-activated K(+) channel that is activated by PI(3)P, is required for macropinocytosis. We propose that the sequential breakdown of PI(3,4,5)P3 → PI(3,4)P2 → PI(3)P → PI controls macropinocytosis through specific effectors of the intermediate phosphoinositides.
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36
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Fu RG, Zhang T, Wang L, Du Y, Jia LN, Hou JJ, Yao GL, Liu XD, Zhang L, Chen L, Gui BS, Xue RL. Inhibition of the K+ channel K(Ca)3.1 reduces TGF-β1-induced premature senescence, myofibroblast phenotype transition and proliferation of mesangial cells. PLoS One 2014; 9:e87410. [PMID: 24489911 PMCID: PMC3905019 DOI: 10.1371/journal.pone.0087410] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 12/25/2013] [Indexed: 01/15/2023] Open
Abstract
Objective KCa3.1 channel participates in many important cellular functions. This study planned to investigate the potential involvement of KCa3.1 channel in premature senescence, myofibroblast phenotype transition and proliferation of mesangial cells. Methods & Materials Rat mesangial cells were cultured together with TGF-β1 (2 ng/ml) and TGF-β1 (2 ng/ml) + TRAM-34 (16 nM) separately for specified times from 0 min to 60 min. The cells without treatment served as controls. The location of KCa3.1 channels in mesangial cells was determined with Confocal laser microscope, the cell cycle of mesangial cells was assessed with flow cytometry, the protein and mRNA expression of KCa3.1, α-smooth muscle actin (α-SMA) and fibroblast-specific protein-1 (FSP-1) were detected with Western blot and RT-PCR. One-way analysis of variance (ANOVA) and Student-Newman-Keuls-q test (SNK-q) were used to do statistical analysis. Statistical significance was considered at P<0.05. Results Kca3.1 channels were located in the cell membranes and/or in the cytoplasm of mesangial cells. The percentage of cells in G0-G1 phase and the expression of Kca3.1, α-SMA and FSP-1 were elevated under the induction of TGF-β1 when compared to the control and decreased under the induction of TGF-β1+TRAM-34 when compared to the TGF-β1 induced (P<0.05 or P<0.01). Conclusion Targeted disruption of KCa3.1 inhibits TGF-β1-induced premature aging, myofibroblast-like phenotype transdifferentiation and proliferation of mesangial cells.
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Affiliation(s)
- Rong-Guo Fu
- Department of Nephrology, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Tao Zhang
- School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Li Wang
- Department of Nephrology, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Yan Du
- Department of Nephrology, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Li-Ning Jia
- Department of Nephrology, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Jing-Jing Hou
- School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Gang-Lian Yao
- Department of Nephrology, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Xiao-Dan Liu
- Cadre's ward, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, P.R. China
| | - Lei Zhang
- Medical Laboratory, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, P.R. China
| | - Ling Chen
- Department of Oncology, First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
| | - Bao-Song Gui
- Department of Nephrology, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
- * E-mail: (RLX); (BSG)
| | - Rong-Liang Xue
- Department of Anesthesia, Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi Province, P.R. China
- * E-mail: (RLX); (BSG)
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A network-based systematic study for the mechanism of the treatment of zhengs related to cough variant asthma. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2013; 2013:595924. [PMID: 24348708 PMCID: PMC3855943 DOI: 10.1155/2013/595924] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Revised: 09/10/2013] [Accepted: 09/12/2013] [Indexed: 02/06/2023]
Abstract
Traditional Chinese medicine (TCM) has shown significant efficacy in the treatment of cough variant asthma (CVA), a special type of asthma. However, there is shortage of explanations for relevant mechanism of treatment. As Zhengs differentiation is a critical concept in TCM, it is necessary to explain the mechanism of treatment of Zhengs. Based on TCM clinical cases, this study illustrated the mechanism of the treatment of three remarkably relevant Zhengs for CVA: “FengXieFanFei,” “FeiQiShiXuan”, and “QiDaoLuanJi.” To achieve this goal, five steps were carried out: (1) determining feature Zhengs and corresponding key herbs of CVA by analyses of clinical cases; (2) finding out potential targets of the key herbs and clustering them based on their functional annotations; (3) constructing an ingredient-herb network and an ingredient network; (4) identifying modules of the ingredient network; (5) illustrating the mechanism of the treatment by further mining the latent biological implications within each module. The systematic study reveals that the treatment of “FengXieFanFei,” “FeiQiShiXuan,” and “QiDaoLuanJi” has effects on the regulation of multiple bioprocesses by herbs containing different ingredients with functions of steroid metabolism regulation, airway inflammation, and ion conduction and transportation. This network-based systematic study will be a good way to boost the scientific understanding of mechanism of the treatment of Zhengs.
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Stock C, Ludwig FT, Hanley PJ, Schwab A. Roles of ion transport in control of cell motility. Compr Physiol 2013; 3:59-119. [PMID: 23720281 DOI: 10.1002/cphy.c110056] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cell motility is an essential feature of life. It is essential for reproduction, propagation, embryonic development, and healing processes such as wound closure and a successful immune defense. If out of control, cell motility can become life-threatening as, for example, in metastasis or autoimmune diseases. Regardless of whether ciliary/flagellar or amoeboid movement, controlled motility always requires a concerted action of ion channels and transporters, cytoskeletal elements, and signaling cascades. Ion transport across the plasma membrane contributes to cell motility by affecting the membrane potential and voltage-sensitive ion channels, by inducing local volume changes with the help of aquaporins and by modulating cytosolic Ca(2+) and H(+) concentrations. Voltage-sensitive ion channels serve as voltage detectors in electric fields thus enabling galvanotaxis; local swelling facilitates the outgrowth of protrusions at the leading edge while local shrinkage accompanies the retraction of the cell rear; the cytosolic Ca(2+) concentration exerts its main effect on cytoskeletal dynamics via motor proteins such as myosin or dynein; and both, the intracellular and the extracellular H(+) concentration modulate cell migration and adhesion by tuning the activity of enzymes and signaling molecules in the cytosol as well as the activation state of adhesion molecules at the cell surface. In addition to the actual process of ion transport, both, channels and transporters contribute to cell migration by being part of focal adhesion complexes and/or physically interacting with components of the cytoskeleton. The present article provides an overview of how the numerous ion-transport mechanisms contribute to the various modes of cell motility.
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Affiliation(s)
- Christian Stock
- Institute of Physiology II, University of Münster, Münster, Germany.
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39
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Ashmole I, Bradding P. Ion channels regulating mast cell biology. Clin Exp Allergy 2013; 43:491-502. [PMID: 23600539 DOI: 10.1111/cea.12043] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2012] [Revised: 07/06/2012] [Accepted: 08/28/2012] [Indexed: 11/28/2022]
Abstract
Mast cells play a central role in the pathophysiology of asthma and related allergic conditions. Mast cell activation leads to the degranulation of preformed mediators such as histamine and the secretion of newly synthesised proinflammatory mediators such as leukotrienes and cytokines. Excess release of these mediators contributes to allergic disease states. An influx of extracellular Ca2+ is essential for mast cell mediator release. From the Ca2+ channels that mediate this influx, to the K+ , Cl- and transient receptor potential channels that set the cell membrane potential and regulate Ca2+ influx, ion channels play a critical role in mast cell biology. In this review we provide an overview of our current knowledge of ion channel expression and function in mast cells with an emphasis on how channels interact to regulate Ca2+ signalling.
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Affiliation(s)
- I Ashmole
- Department of Infection, Immunity and Inflammation, Institute for Lung Heath, Glenfield Hospital, University of Leicester, Leicester, LE3 9QP, UK
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Up-regulation of KCa3.1 promotes human airway smooth muscle cell phenotypic modulation. Pharmacol Res 2013; 77:30-8. [PMID: 24055799 DOI: 10.1016/j.phrs.2013.09.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Revised: 08/26/2013] [Accepted: 09/08/2013] [Indexed: 02/06/2023]
Abstract
Airway smooth muscle (ASM) cell phenotype modulation, characterized by reversible switching between contractile and proliferative phenotypes, is considered to contribute to proliferative diseases such as allergic asthma and chronic obstructive pulmonary disease (COPD). KCa3.1 has been suggested to be involved in regulating ASM cell activation, proliferation, and migration. However, little is known regarding the exact role of KCa3.1 in ASM cell phenotypic modulation. To elucidate the role of KCa3.1 in regulating ASM cell phenotypic modulation, we investigated the effects of KCa3.1 channels on ASM contractile marker protein expression, proliferation and migration of primary human bronchial smooth muscle (BSM) cells. We found that PDGF increased KCa3.1 channel expression in BSM cells with a concomitant marked decrease in the expression of contractile phenotypic marker proteins including smooth muscle myosin heavy chain (SMMHC), smooth muscle α-actin (α-SMA), myocardin and KCa1.1. These changes were significantly attenuated by the KCa3.1 blocker, TRAM-34, or gene silencing of KCa3.1. Pharmacological blockade or gene silencing of KCa3.1 also suppressed PDGF-induced human BSM cell migration and proliferation accompanied by a decrease in intracellular free Ca(2+) levels as a consequence of membrane depolarization, resulting in a reduction in cyclin D1 level and cell cycle arrest at G0-G1 phase. Additionally, PDGF-induced up-regulation of KCa3.1 and down-regulation of BSM contractile marker proteins were regulated by the ERK inhibitor U0126 and the AKT inhibitor LY294002. These findings highlight a novel role for the KCa3.1 channel in human BSM cell phenotypic modulation and provide a potential target for therapeutic intervention for proliferative airway diseases.
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Yu ZH, Xu JR, Wang YX, Xu GN, Xu ZP, Yang K, Wu DZ, Cui YY, Chen HZ. Targeted inhibition of KCa3.1 channel attenuates airway inflammation and remodeling in allergic asthma. Am J Respir Cell Mol Biol 2013; 48:685-93. [PMID: 23492185 DOI: 10.1165/rcmb.2012-0236oc] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
KCa3.1 has been suggested to be involved in regulating cell activation, proliferation, and migration in multiple cell types, including airway inflammatory and structural cells. However, the contributions of KCa3.1 to airway inflammation and remodeling and subsequent airway hyperresponsiveness (AHR) in allergic asthma remain to be explored. The main purpose of this study was to elucidate the roles of KCa3.1 and the potential therapeutic value of KCa3.1 blockers in chronic allergic asthma. Using real-time PCR, Western blotting, or immunohistochemical analyses, we explored the precise role of KCa3.1 in the bronchi of allergic mice and asthmatic human bronchial smooth muscle cells (BSMCs). We found that KCa3.1 mRNA and protein expression were elevated in the bronchi of allergic mice, and double labeling revealed that up-regulation occurred primarily in airway smooth muscle cells. Triarylmethane (TRAM)-34, a KCa3.1 blocker, dose-dependently inhibited the generation and maintenance of the ovalbumin-induced airway inflammation associated with increased Th2-type cytokines and decreased Th1-type cytokine, as well as subepithelial extracellular matrix deposition, goblet-cell hyperplasia, and AHR in a murine model of asthma. Moreover, the pharmacological blockade and gene silencing of KCa3.1, which was evidently elevated after mitogen stimulation, suppressed asthmatic human BSMC proliferation and migration, and arrested the cell cycle at the G0/G1 phase. In addition, the KCa3.1 activator 1-ethylbenzimidazolinone-induced membrane hyperpolarization and intracellular calcium increase in asthmatic human BSMCs were attenuated by TRAM-34. We demonstrate for the first time an important role for KCa3.1 in the pathogenesis of airway inflammation and remodeling in allergic asthma, and we suggest that KCa3.1 blockers may represent a promising therapeutic strategy for asthma.
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Affiliation(s)
- Zhi-Hua Yu
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China
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Endothelial small-conductance and intermediate-conductance KCa channels: an update on their pharmacology and usefulness as cardiovascular targets. J Cardiovasc Pharmacol 2013; 61:102-12. [PMID: 23107876 DOI: 10.1097/fjc.0b013e318279ba20] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Most cardiovascular researchers are familiar with intermediate-conductance KCa3.1 and small-conductance KCa2.3 channels because of their contribution to endothelium-derived hyperpolarization. However, to immunologists and neuroscientists, these channels are primarily known for their role in lymphocyte activation and neuronal excitability. KCa3.1 is involved in the proliferation and migration of T cells, B cells, mast cells, macrophages, fibroblasts, and dedifferentiated vascular smooth muscle cells and is, therefore, being pursued as a potential target for use in asthma, immunosuppression, and fibroproliferative disorders. In contrast, the 3 KCa2 channels (KCa2.1, KCa2.2, and KCa2.3) contribute to the neuronal medium afterhyperpolarization and, depending on the type of neuron, are involved in determining firing rates and frequencies or in regulating bursting. KCa2 activators are accordingly being studied as potential therapeutics for ataxia and epilepsy, whereas KCa2 channel inhibitors like apamin have long been known to improve learning and memory in rodents. Given this background, we review the recent discoveries of novel KCa3.1 and KCa2.3 modulators and critically assess the potential of KCa activators for the treatment of diabetes and cardiovascular diseases by improving endothelium-derived hyperpolarizations.
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Van Der Velden J, Sum G, Barker D, Koumoundouros E, Barcham G, Wulff H, Castle N, Bradding P, Snibson K. K(Ca)3.1 channel-blockade attenuates airway pathophysiology in a sheep model of chronic asthma. PLoS One 2013; 8:e66886. [PMID: 23826167 PMCID: PMC3691218 DOI: 10.1371/journal.pone.0066886] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 05/12/2013] [Indexed: 11/18/2022] Open
Abstract
Background The Ca2+-activated K+ channel KCa3.1 is expressed in several structural and inflammatory airway cell types and is proposed to play an important role in the pathophysiology of asthma. The aim of the current study was to determine whether inhibition of KCa3.1 modifies experimental asthma in sheep. Methodology and Principal Findings Atopic sheep were administered either 30 mg/kg Senicapoc (ICA-17073), a selective inhibitor of the KCa3.1-channel, or vehicle alone (0.5% methylcellulose) twice daily (orally). Both groups received fortnightly aerosol challenges with house dust mite allergen for fourteen weeks. A separate sheep group received no allergen challenges or drug treatment. In the vehicle-control group, twelve weeks of allergen challenges resulted in a 60±19% increase in resting airway resistance, and this was completely attenuated by treatment with Senicapoc (0.25±12%; n = 10, P = 0.0147). The vehicle-control group had a peak-early phase increase in lung resistance of 82±21%, and this was reduced by 58% with Senicapoc treatment (24±14%; n = 10, P = 0.0288). Senicapoc-treated sheep also demonstrated reduced airway hyperresponsiveness, requiring a significantly higher dose of carbachol to increase resistance by 100% compared to allergen-challenged vehicle-control sheep (20±5 vs. 52±18 breath-units of carbachol; n = 10, P = 0.0340). Senicapoc also significantly reduced eosinophil numbers in bronchoalveolar lavage taken 48 hours post-allergen challenge, and reduced vascular remodelling. Conclusions These findings suggest that KCa3.1-activity contributes to allergen-induced airway responses, inflammation and vascular remodelling in a sheep model of asthma, and that inhibition of KCa3.1 may be an effective strategy for blocking allergen-induced airway inflammation and hyperresponsiveness in humans.
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Affiliation(s)
- Joanne Van Der Velden
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
- Lung Health Research Centre, Department of Pharmacology, University of Melbourne, Parkville, Victoria, Australia
| | - Grace Sum
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Donna Barker
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Emmanuel Koumoundouros
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
- Department of Electrical and Electronic Engineering, University of Melbourne, Parkville, Victoria, Australia
| | - Garry Barcham
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
| | - Heike Wulff
- Department of Pharmacology, University of California Davis, Davis, California, United States of America
| | - Neil Castle
- Icagen Inc., Durham, North Carolina, United States of America
| | - Peter Bradding
- Department of Infection, Immunity and Inflammation, Institute for Lung Health, University of Leicester, Leicester, United Kingdom
| | - Kenneth Snibson
- Faculty of Veterinary Science, The University of Melbourne, Parkville, Victoria, Australia
- * E-mail:
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Wang J, Xiang M. Targeting potassium channels Kv1.3 and KC a 3.1: routes to selective immunomodulators in autoimmune disorder treatment? Pharmacotherapy 2013; 33:515-28. [PMID: 23649812 DOI: 10.1002/phar.1236] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The Kv1.3 and KC a 3.1 potassium channels are promising targets for the treatment of autoimmune disorders. Many Kv1.3 and KC a 3.1 blockers have a more favorable adverse event profiles than existing immunosuppressants, suggesting the selectivity of Kv1.3 and KC a 3.1 blockade. The Kv1.3 and KC a 3.1 blockers exert differential effects in different autoimmune diseases. The Kv1.3 inhibitors or gene deletion have been shown to have benefits in multiple sclerosis, type 1 diabetes, rheumatoid arthritis, psoriasis, and rapidly progressive glomerulonephritis. The KC a 3.1 blockers have demonstrated efficacy in human primary biliary cirrhosis and showed protective effects in animal models of severe colitis, allergic encephalomyelitis, inflammatory bowel disease, and multiple sclerosis. The KC a 3.1 blockers are not considered candidates for treatment of multiple sclerosis. The selective immunosuppressive effects of the Kv1.3 and KC a 3.1 blockers are due to the differences in their distribution on autoimmune-related immune cells and tissues and β1 integrin (very late activating antigen)-Kv1.3 channel cross-talk.
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Affiliation(s)
- Jun Wang
- Department of Pharmacology, School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Schwab A, Fabian A, Hanley PJ, Stock C. Role of ion channels and transporters in cell migration. Physiol Rev 2013; 92:1865-913. [PMID: 23073633 DOI: 10.1152/physrev.00018.2011] [Citation(s) in RCA: 315] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cell motility is central to tissue homeostasis in health and disease, and there is hardly any cell in the body that is not motile at a given point in its life cycle. Important physiological processes intimately related to the ability of the respective cells to migrate include embryogenesis, immune defense, angiogenesis, and wound healing. On the other side, migration is associated with life-threatening pathologies such as tumor metastases and atherosclerosis. Research from the last ≈ 15 years revealed that ion channels and transporters are indispensable components of the cellular migration apparatus. After presenting general principles by which transport proteins affect cell migration, we will discuss systematically the role of channels and transporters involved in cell migration.
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Kroigaard C, Dalsgaard T, Nielsen G, Laursen BE, Pilegaard H, Köhler R, Simonsen U. Activation of endothelial and epithelial K(Ca) 2.3 calcium-activated potassium channels by NS309 relaxes human small pulmonary arteries and bronchioles. Br J Pharmacol 2013; 167:37-47. [PMID: 22506557 DOI: 10.1111/j.1476-5381.2012.01986.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Small (K(Ca) 2) and intermediate (K(Ca) 3.1) conductance calcium-activated potassium channels (K(Ca) ) may contribute to both epithelium- and endothelium-dependent relaxations, but this has not been established in human pulmonary arteries and bronchioles. Therefore, we investigated the expression of K(Ca) 2.3 and K(Ca) 3.1 channels, and hypothesized that activation of these channels would produce relaxation of human bronchioles and pulmonary arteries. EXPERIMENTAL APPROACH Channel expression and functional studies were conducted in human isolated small pulmonary arteries and bronchioles. K(Ca) 2 and K(Ca) 3.1 currents were examined in human small airways epithelial (HSAEpi) cells by whole-cell patch clamp techniques. RESULTS While K(Ca) 2.3 expression was similar, K(Ca) 3.1 protein was more highly expressed in pulmonary arteries than bronchioles. Immunoreactive K(Ca) 2.3 and K(Ca) 3.1 proteins were found in both endothelium and epithelium. K(Ca) currents were present in HSAEpi cells and sensitive to the K(Ca) 2.3 blocker UCL1684 and the K(Ca) 3.1 blocker TRAM-34. In pulmonary arteries contracted by U46619 and in bronchioles contracted by histamine, the K(Ca) 2.3/ K(Ca) 3.1 activator, NS309, induced concentration-dependent relaxations. NS309 was equally potent in relaxing pulmonary arteries, but less potent in bronchioles, than salbutamol. NS309 relaxations were blocked by the K(Ca) 2 channel blocker apamin, while the K(Ca) 3.1 channel blocker, charybdotoxin failed to reduce relaxation to NS309 (0.01-1 µM). CONCLUSIONS AND IMPLICATIONS K(Ca) 2.3 and K(Ca) 3.1 channels are expressed in the endothelium of human pulmonary arteries and epithelium of bronchioles. K(Ca) 2.3 channels contributed to endo- and epithelium-dependent relaxations suggesting that these channels are potential targets for treatment of pulmonary hypertension and chronic obstructive pulmonary disease.
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Affiliation(s)
- Christel Kroigaard
- Department of Biomedicine, Pulmonary and Cardiovascular Pharmacology, Faculty of Health Sciences, Aarhus University, Aarhus C, Denmark
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Girodet PO, Ozier A, Carvalho G, Ilina O, Ousova O, Gadeau AP, Begueret H, Wulff H, Marthan R, Bradding P, Berger P. Ca(2+)-activated K(+) channel-3.1 blocker TRAM-34 attenuates airway remodeling and eosinophilia in a murine asthma model. Am J Respir Cell Mol Biol 2012. [PMID: 23204391 DOI: 10.1165/rcmb.2012-0103oc] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Key features of asthma include bronchial hyperresponsiveness (BHR), eosinophilic airway inflammation, and bronchial remodeling, characterized by subepithelial collagen deposition, airway fibrosis, and increased bronchial smooth muscle (BSM) mass. The calcium-activated K(+) channel K(Ca)3.1 is expressed by many cells implicated in the pathogenesis of asthma, and is involved in both inflammatory and remodeling responses in a number of tissues. The specific K(Ca)3.1 blocker 5-[(2-chlorophenyl)(diphenyl)methyl]-1H-pyrazole (TRAM-34) attenuates BSM cell proliferation, and both mast cell and fibrocyte recruitment in vitro. We aimed to examine the effects of K(Ca)3.1 blockade on BSM remodeling, airway inflammation, and BHR in a murine model of chronic asthma. BALB/c mice were sensitized with intraperitoneal ovalbumin (OVA) on Days 0 and 14, and then challenged with intranasal OVA during Days 14-75. OVA-sensitized/challenged mice received TRAM-34 (120 mg/kg/day, subcutaneous) from Days -7 to 75 (combined treatment), Days -7 to 20 (preventive treatment), or Days 21 to 75 (curative treatment). Untreated mice received daily injections of vehicle (n = 8 per group). Bronchial remodeling was assessed by histological and immunohistochemical analyses. Inflammation was evaluated using bronchoalveolar lavage and flow cytometry. We also determined BHR in both conscious and anesthetized mice via plethysmography. We demonstrated that curative treatment with TRAM-34 abolishes BSM remodeling and subbasement collagen deposition, and attenuates airway eosinophilia. Although curative treatment alone did not significantly reduce BHR, the combined treatment attenuated nonspecific BHR to methacholine. This study indicates that K(Ca)3.1 blockade could provide a new therapeutic strategy in asthma.
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Affiliation(s)
- Pierre-Olivier Girodet
- Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, U1034, De´partement de Pharmacologie, CIC 0005, University of Bordeaux, Bordeaux, France
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Bergeron ZL, Bingham JP. Scorpion toxins specific for potassium (K+) channels: a historical overview of peptide bioengineering. Toxins (Basel) 2012. [PMID: 23202307 PMCID: PMC3509699 DOI: 10.3390/toxins4111082] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Scorpion toxins have been central to the investigation and understanding of the physiological role of potassium (K+) channels and their expansive function in membrane biophysics. As highly specific probes, toxins have revealed a great deal about channel structure and the correlation between mutations, altered regulation and a number of human pathologies. Radio- and fluorescently-labeled toxin isoforms have contributed to localization studies of channel subtypes in expressing cells, and have been further used in competitive displacement assays for the identification of additional novel ligands for use in research and medicine. Chimeric toxins have been designed from multiple peptide scaffolds to probe channel isoform specificity, while advanced epitope chimerization has aided in the development of novel molecular therapeutics. Peptide backbone cyclization has been utilized to enhance therapeutic efficiency by augmenting serum stability and toxin half-life in vivo as a number of K+-channel isoforms have been identified with essential roles in disease states ranging from HIV, T-cell mediated autoimmune disease and hypertension to various cardiac arrhythmias and Malaria. Bioengineered scorpion toxins have been monumental to the evolution of channel science, and are now serving as templates for the development of invaluable experimental molecular therapeutics.
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Affiliation(s)
- Zachary L Bergeron
- Department of Molecular Biosciences and Bioengineering, College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
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Balut CM, Hamilton KL, Devor DC. Trafficking of intermediate (KCa3.1) and small (KCa2.x) conductance, Ca(2+)-activated K(+) channels: a novel target for medicinal chemistry efforts? ChemMedChem 2012; 7:1741-55. [PMID: 22887933 DOI: 10.1002/cmdc.201200226] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Revised: 07/09/2012] [Indexed: 12/22/2022]
Abstract
Ca(2+)-activated K(+) (KCa) channels play a pivotal role in the physiology of a wide variety of tissues and disease states, including vascular endothelia, secretory epithelia, certain cancers, red blood cells (RBC), neurons, and immune cells. Such widespread involvement has generated an intense interest in elucidating the function and regulation of these channels, with the goal of developing pharmacological strategies aimed at selective modulation of KCa channels in various disease states. Herein we give an overview of the molecular and functional properties of these channels and their therapeutic importance. We discuss the achievements made in designing pharmacological tools that control the function of KCa channels by modulating their gating properties. Moreover, this review discusses the recent advances in our understanding of KCa channel assembly and anterograde trafficking toward the plasma membrane, the micro-domains in which these channels are expressed within the cell, and finally the retrograde trafficking routes these channels take following endocytosis. As the regulation of intracellular trafficking by agonists as well as the protein-protein interactions that modify these events continue to be explored, we anticipate this will open new therapeutic avenues for the targeting of these channels based on the pharmacological modulation of KCa channel density at the plasma membrane.
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Affiliation(s)
- Corina M Balut
- Department of Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261, USA
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