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Standardized Extract of Atractylodis Rhizoma Alba and Fructus Schisandrae Ameliorates Coughing and Increases Expectoration of Phlegm. Molecules 2020; 25:molecules25133064. [PMID: 32635583 PMCID: PMC7411911 DOI: 10.3390/molecules25133064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 06/25/2020] [Accepted: 07/02/2020] [Indexed: 01/17/2023] Open
Abstract
Cough and phlegm frequently occur in respiratory diseases like upper respiratory tract infections, acute bronchitis, and chronic obstructive pulmonary diseases. To relieve these symptoms and diseases, various ingredients are being used despite the debates on their clinical efficacy. We aimed to investigate the effects of the extract CKD-497, composed of Atractylodis Rhizoma Alba and Fructus Schisandrae, in relieving cough and facilitating expectoration of phlegm. CKD-497 was found to inhibit inflammatory mediators such as interleukin-8 (IL-8) and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-treated mouse macrophages and transient receptor potential cation channel 1 (TRPV-1)-overexpressed human bronchial epithelial cells stimulated by capsaicin. CKD-497 decreased the viscosity of the mucin solution. During in vivo experiments, CKD-497 reduced coughing numbers and increased expectoration of phlegm via mucociliary clearance enhancement. Collectively, these data suggest that CKD-497 possesses potential for cough and phlegm expectoration treatment.
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Higashi E, Hirayama S, Nikaido J, Shibasaki M, Kono T, Honjo A, Ikeda H, Kamei J, Fujii H. Development of Novel δ Opioid Receptor Inverse Agonists without a Basic Nitrogen Atom and Their Antitussive Effects in Mice. ACS Chem Neurosci 2019; 10:3939-3945. [PMID: 31397148 DOI: 10.1021/acschemneuro.9b00368] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Our previous results showed that naltrindole (NTI) derivatives with certain types of electron-withdrawing groups as an N-substituent showed δ opioid receptor (DOR) inverse agonistic activities. We therefore synthesized N-acylated NTI derivatives 3a-e and observed that N-benzoyl and N-cyclopropanecarbonyl derivatives SYK-736 (3b) and SYK-623 (3c) were DOR full inverse agonists and the N-acryloyl derivative 3d was a DOR partial inverse agonist. SKY-623 was over 110-fold more potent than the reference compound ICI-174,864. Both naltriben (NTB) and 7-benzylidenenaltrexone (BNTX) derivatives with N-benzoyl and N-cyclopropanecarbonyl groups were also DOR full inverse agonists. These N-acylated inverse agonists are interesting compounds because they have no basic nitrogen atom, which has been demonstrated to be an important pharmacophore. NTI and BNTX-type DOR inverse agonists SYK-623 and SYK-723 (12c) showed dose-dependent antitussive effects in a mouse cough model induced by citric acid exposure. The antitussive effects by SYK-623 and SYK-723 were significantly attenuated by pretreatment with DOR agonist SNC80.
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Affiliation(s)
- Eika Higashi
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
| | - Shigeto Hirayama
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
- Medicinal Research Laboratories, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
| | - Jun Nikaido
- Department of Pathophysiology and Therapeutics, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
| | - Marie Shibasaki
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
| | - Tomomi Kono
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
| | - Ayaka Honjo
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
| | - Hiroko Ikeda
- Department of Pathophysiology and Therapeutics, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
| | - Junzo Kamei
- Department of Pathophysiology and Therapeutics, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
- Global Research Center for Innovative Life Science, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Shinagawa-ku, Tokyo 142-8501, Japan
| | - Hideaki Fujii
- Laboratory of Medicinal Chemistry, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
- Medicinal Research Laboratories, School of Pharmacy, Kitasato University, 5-9-1, Shirokane,
Minato-ku, Tokyo 108-8641, Japan
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Bronchodilator therapy for chronic cough. Pulm Pharmacol Ther 2017; 47:88-92. [PMID: 28527922 DOI: 10.1016/j.pupt.2017.05.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 05/12/2017] [Accepted: 05/16/2017] [Indexed: 02/08/2023]
Abstract
Experimental studies indicate that airway calibre increases the sensitivity of the afferents involved in the cough reflex but it has proved difficult to demonstrate that airway calibre increases the sensitivity of the afferents involved in the cough reflex. Therefore, bronchodilators might have a role, although rather minor, in the treatment of cough. However, although bronchodilators represent the standard of care in the treatment of airway obstruction associated with asthma or COPD, controversy persists regarding the mechanism(s) by which these agents alleviate cough. Furthermore, the available evidence indicates that the effects of bronchodilators on cough are rather inconsistent in humans and casts doubt on the appropriateness of the common practice of using bronchodilators in the treatment of patients with cough without any other evidence of airway obstruction. Regrettably, appropriate long-term trials specifically aimed at evaluating the clinical efficacy of bronchodilators in pathologic cough have not yet been performed. Therefore, properly executed clinical studies of bronchodilators in various types of acute and chronic pathologic cough are required.
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Antitussive effect of carcainium chloride in patients with chronic cough and idiopathic interstitial pneumonias: A pilot study. Pulm Pharmacol Ther 2016; 40:91-4. [PMID: 27538683 DOI: 10.1016/j.pupt.2016.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 07/27/2016] [Accepted: 08/02/2016] [Indexed: 11/21/2022]
Abstract
BACKGROUND Cough is a common presenting symptom in patients with idiopathic interstitial pneumonia (IIP); it is often disabling, and lacks effective treatment. Studies in animals suggest that carcainium chloride, a quaternary derivative of the local anesthetic lidocaine, is able to inhibit experimentally induced cough by a mechanism of action distinct from that of lidocaine. OBJECTIVE To determine the effectiveness of aerosolised carcainium chloride (VRP700) in controlling cough in patients with IIP. METHODS Eight female patients (mean age 71 years) with IIP were investigated in a double blind, randomised, placebo controlled crossover, adaptive contingency study design (EudraCT Number 2010-021350-19). The study consisted of a screening visit to assess the eligibility of patients, and two separated (48-72 h) study days. On the two study days, patients were randomised to receive either nebulized VRP700 (1.0 mg/kg) on the first study visit followed by nebulised placebo (sodium chloride 0.9%) on the second visit, or placebo on the first visit followed by VRP700 on the second visit. The primary endpoint was cough frequency over a 4-h assessment period; secondary endpoints were subjective cough-related level of discomfort as assessed by a visual analogue scale (VAS) and the subjective response to treatment as assessed by a quality of life question. Safety (ECG, spirometry, urine and blood tests) and adverse events occurring during the trial were also investigated. RESULTS In all patients both VRP700 and placebo decreased cough frequency; however, mean decreases in cough frequency after treatment with VRP700 were significantly (P < 0.001) higher than with placebo. Similarly, mean reductions in VAS score were significantly (P < 0.001) higher after treatment with VRP 700 compared with placebo. All but one patient indicated that they felt better after receiving VRP700. No adverse events were reported during the study, nor were any changes in ECG variables, spirometry, urine and blood tests noted. CONCLUSION The results of this exploratory study indicate that nebulised VRP700 improved cough and quality of life in hospitalised IIP patients with no significant side effects. A larger trial is warranted to assess these promising results.
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Mutolo D, Cinelli E, Iovino L, Pantaleo T, Bongianni F. Downregulation of the cough reflex by aclidinium and tiotropium in awake and anesthetized rabbits. Pulm Pharmacol Ther 2016; 38:1-9. [DOI: 10.1016/j.pupt.2016.04.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 04/08/2016] [Accepted: 04/10/2016] [Indexed: 01/23/2023]
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Cough in interstitial lung disease. Pulm Pharmacol Ther 2015; 35:122-8. [DOI: 10.1016/j.pupt.2015.10.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 10/22/2015] [Accepted: 10/23/2015] [Indexed: 12/15/2022]
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Chung KF, Canning B, McGarvey L. Eight International London Cough Symposium 2014: Cough hypersensitivity syndrome as the basis for chronic cough. Pulm Pharmacol Ther 2015; 35:76-80. [PMID: 26341666 DOI: 10.1016/j.pupt.2015.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 08/31/2015] [Indexed: 02/01/2023]
Abstract
At the Eighth International London Cough Conference held in London in July 2014, the focus was on the relatively novel concept of cough hypersensitivity syndrome (CHS) as forming the basis of chronic cough. This concept has been formulated following understanding of the neuronal pathways for cough and a realisation that not all chronic cough is usually associated with a cause. The CHS is defined by troublesome coughing triggered by low level of thermal, mechanical or chemical exposure. It also encompasses other symptoms or sensations such as laryngeal hypersensitivity, nasal hypersensitivity and possibly also symptoms related to gastrooesopahgeal reflux. The pathophysiologic basis of the CHS is now being increasingly linked to an enhancement of the afferent pathways of the cough reflex both at the peripheral and central levels. Mechanisms involved include the interactions of inflammatory mechanisms with cough sensors in the upper airways and with neuronal pathways of cough, associated with a central component. Tools for assessing CHS in the clinic need to be developed. New drugs may be developed to control CHS. A roadmap is suggested from the inception of the CHS concept towards the development of newer antitussives at the Symposium.
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Affiliation(s)
- Kian Fan Chung
- Experimental Studies, National Heart and Lung Institute, Imperial College London, UK; Royal Brompton NIHR Biomedical Research Unit, London, UK.
| | - Brendan Canning
- The Johns Hopkins Asthma and Allergy Center, Baltimore, MD 21224, USA
| | - Lorcan McGarvey
- Department of Respiratory Medicine, Centre for Infection and Immunity, Queen's University Belfast, UK
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Gibson PG, Vertigan AE. Gabapentin in chronic cough. Pulm Pharmacol Ther 2015; 35:145-8. [PMID: 26141016 DOI: 10.1016/j.pupt.2015.06.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 06/22/2015] [Accepted: 06/26/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND Chronic cough is regarded as a challenging clinical problem due to its frequency and often limited therapeutic options. Chronic cough that remains refractory to usual medical treatment causes significant quality of life impairment. METHODS Recent developments in the treatment of cough include the use of speech pathology and pharmacotherapy with gabapentin. Relevant randomised control trials, reviews and case reports were identified through a PubMed and SCOPUS search of English-language literature referring to these concepts over the last eight years. RESULTS The effectiveness of neuromodulating medications such as gabapentin and pregabalin in the treatment of cough has been supported primarily through case series, case reports, prospective reviews and a double blind randomised controlled trial. Gabapentin results in a reduction in cough frequency and cough severity. It improves cough related quality of life. The effect is greatest in patients with features of central reflex sensitisation such as laryngeal paraesthesia, hypertussia and allotussia. These symptoms can be measured using the Newcastle Laryngeal Hypersensitivity Questionnaire. Side effects of gabapentin include somnolence and dizziness. CONCLUSION Recent additions in the treatment of chronic cough have been significant as they consider cough to have a unifying diagnosis of cough hypersensitivity with or without the presence of a neuropathic basis. Effective treatments for refractory chronic cough that target these areas include behavioural treatment such as speech pathology and pharmaceutical treatment with neuromodulating medications such as gabapentin.
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Affiliation(s)
- Peter G Gibson
- Centre for Asthma and Respiratory Diseases, School of Medicine and Public Health, Hunter Medical Research Institute, The University of Newcastle, NSW 2305, Australia; Department of Respiratory and Sleep Medicine, John Hunter Hospital, New Lambton Heights, NSW 2305, Australia.
| | - Anne E Vertigan
- Centre for Asthma and Respiratory Diseases, School of Medicine and Public Health, Hunter Medical Research Institute, The University of Newcastle, NSW 2305, Australia; Speech Pathology, John Hunter Hospital, New Lambton Heights, NSW 2305, Australia
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Ryan NM, Gibson PG. Recent additions in the treatment of cough. J Thorac Dis 2014; 6:S739-47. [PMID: 25383209 DOI: 10.3978/j.issn.2072-1439.2014.03.13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 03/04/2014] [Indexed: 11/14/2022]
Abstract
BACKGROUND Worldwide, cough is regarded as a challenging clinical problem due to its frequency and often limited therapeutic options. Chronic cough that remains refractory to usual medical treatment causes significant quality of life impairment in people with this problem. METHODS We have examined current evidence on recent additions in the treatment of cough, specifically treatment of refractory chronic cough with speech pathology and gabapentin. Relevant randomised control trials, reviews and case reports were identified through a PubMed and SCOPUS search of English-language literature referring to these concepts over the last eight years. SUMMARY Of the one hundred and two articles comprising this review the majority investigated the role of the transient receptor potential (TRP) receptors TRP Vanilloid 1 (TRPV1) and TRPA1 in cough and the potential of TRP antagonists as effective anti-tussives. However, these have only been tested in the laboratory and therefore their clinical effectiveness is unknown. Behavioural treatments such as speech pathology have gained momentum and this was evident in the increasing number of articles investigating its positive effect on cough. Investigation on the effectiveness of neuromodulating medications in the treatment of cough have been supported primarily through case series reports and prospective reviews however; their use (particularly gabapentin) has been significantly advanced through recently conducted randomised controlled trials. CONCLUSIONS Recent additions in the treatment of chronic cough have been significant as they consider cough to have a unifying diagnosis of cough hypersensitivity with or without the presence of a neuropathic basis. Primarily, effective treatments for chronic cough target these areas and include behavioural treatment such as speech pathology and pharmaceutical treatment with neuromodulating medications such as gabapentin.
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Affiliation(s)
- Nicole M Ryan
- 1 Priority Centre for Asthma and Respiratory Diseases, School of Medicine and Public Health, The University of Newcastle, NSW 2308, Australia ; 2 VIVA, Level 2 West Wing, Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
| | - Peter G Gibson
- 1 Priority Centre for Asthma and Respiratory Diseases, School of Medicine and Public Health, The University of Newcastle, NSW 2308, Australia ; 2 VIVA, Level 2 West Wing, Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
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Ryan NM. A review on the efficacy and safety of gabapentin in the treatment of chronic cough. Expert Opin Pharmacother 2014; 16:135-45. [PMID: 25380977 DOI: 10.1517/14656566.2015.981524] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Effective antitussives available to control cough are limited. Consolidation among different afferent branches of the vagus nerve is needed to bring about cough. A general, widely accepted view is that the chronic increase in the sensitivity of the cough reflex is associated with inflammatory hypersensitivity such as from gastro-esophageal reflux disease. There is increasing evidence that an important mechanism is a sensory disorder of the laryngeal branches of the vagus nerve. Neuromodulating drugs are effectively used in the treatment of chronic pain and neuropathic disorders and may have a role in the treatment of refractory chronic cough (CC). AREAS COVERED Current evidence on the efficacy and safety of gabapentin in the treatment of CC is reviewed. Relevant randomized controlled trials, case reports and reviews were identified through a PubMed search of English-language literature referring to cough, sensory neuropathy and gabapentin over the last 10 years. EXPERT OPINION Gabapentin appears to be effective and well tolerated in the treatment of CC and in other sensory neuropathic disorders. Relevant clinical trials investigating its efficacy and safety profile in the treatment of cough are limited and further studies are needed. Gabapentin has been shown to cause minimal to no toxicity in overdose.
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Affiliation(s)
- Nicole M Ryan
- NHMRC Post-Doc Research Fellow, The University of Newcastle, School of Medicine and Public Health, Clinical Toxicology and Pharmacology , Newcastle, NSW 2308 , Australia
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Nilius B, Szallasi A. Transient Receptor Potential Channels as Drug Targets: From the Science of Basic Research to the Art of Medicine. Pharmacol Rev 2014; 66:676-814. [DOI: 10.1124/pr.113.008268] [Citation(s) in RCA: 348] [Impact Index Per Article: 34.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Kaneko Y, Szallasi A. Transient receptor potential (TRP) channels: a clinical perspective. Br J Pharmacol 2014; 171:2474-507. [PMID: 24102319 PMCID: PMC4008995 DOI: 10.1111/bph.12414] [Citation(s) in RCA: 283] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 08/28/2013] [Accepted: 08/31/2013] [Indexed: 12/14/2022] Open
Abstract
Transient receptor potential (TRP) channels are important mediators of sensory signals with marked effects on cellular functions and signalling pathways. Indeed, mutations in genes encoding TRP channels are the cause of several inherited diseases in humans (the so-called 'TRP channelopathies') that affect the cardiovascular, renal, skeletal and nervous systems. TRP channels are also promising targets for drug discovery. The initial focus of research was on TRP channels that are expressed on nociceptive neurons. Indeed, a number of potent, small-molecule TRPV1, TRPV3 and TRPA1 antagonists have already entered clinical trials as novel analgesic agents. There has been a recent upsurge in the amount of work that expands TRP channel drug discovery efforts into new disease areas such as asthma, cancer, anxiety, cardiac hypertrophy, as well as obesity and metabolic disorders. A better understanding of TRP channel functions in health and disease should lead to the discovery of first-in-class drugs for these intractable diseases. With this review, we hope to capture the current state of this rapidly expanding and changing field.
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Affiliation(s)
- Yosuke Kaneko
- Discovery Research Alliance, Ono Pharmaceutical Co. LtdOsaka, Japan
| | - Arpad Szallasi
- Department of Pathology and Laboratory Medicine, Monmouth Medical CenterLong Branch, NJ, USA
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McGarvey L. Update: the search for the human cough receptor. Lung 2014; 192:459-65. [PMID: 24770379 DOI: 10.1007/s00408-014-9581-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Accepted: 03/29/2014] [Indexed: 10/25/2022]
Abstract
Despite the best efforts of basic and applied science, the identity of the human "cough receptor" remains elusive. The attraction of identifying a single "catch all" cough receptor is obvious, although such an objective is unlikely to be realised given the concept of "cough hypersensitivity," which is now considered the most clinically relevant description of what underlies problem coughing. One means of progressing this area is to join the thinking and experimental effort of basic science and clinical research in an effective manner. Some of the best examples of cooperative and translational research over the years together with an update on the most recent work will be discussed in this article.
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Affiliation(s)
- Lorcan McGarvey
- Centre for Infection and Immunity, Queens University Belfast, Health Sciences Building, Lisburn Road, Belfast, BT9 7BL, Northern Ireland,
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Wang ZJ, Levinson SR, Sun L, Heinbockel T. Identification of both GABAA receptors and voltage-activated Na(+) channels as molecular targets of anticonvulsant α-asarone. Front Pharmacol 2014; 5:40. [PMID: 24653701 PMCID: PMC3949418 DOI: 10.3389/fphar.2014.00040] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 02/20/2014] [Indexed: 01/09/2023] Open
Abstract
Alpha (α)-asarone, a major effective component isolated from the Chinese medicinal herb Acorus tatarinowii, is clinically used as medication for treating epilepsy, cough, bronchitis, and asthma. In the present study, we demonstrated that α-asarone targets central nervous system GABAA receptor as well as voltage-gated Na(+) channels. Using whole-cell patch-clamp recording, α-asarone inhibited spontaneous firing of output neurons, mitral cells (MCs), in mouse olfactory bulb brain slice preparation and hyperpolarized the membrane potential of MCs. The inhibitory effect of α-asarone persisted in the presence of ionotropic glutamate receptor blockers but was eliminated after adding a GABAA receptor blocker, suggesting that GABAA receptors mediated the inhibition of MCs by α-asarone. This hypothesis was supported by the finding that α-asarone evoked an outward current, but did not influence inhibitory postsynaptic currents (IPSCs). In addition to inhibiting spontaneous firing, α-asarone also inhibited the Nav1.2 channel, a dominant rat brain Na(+) channel subtype. The effects of α-asarone on a defined Nav1.2 were characterized using transfected cells that stably expressed the Nav1.2 channel isoform. α-Asarone displayed strong tonic inhibition of Nav1.2 currents in a concentration- and membrane potential-dependent fashion. α-Asarone reduced channel availability in steady-state inactivation protocols by enhancing or stabilizing Na(+) channel inactivation. Both Na(+) channel blockade and activation of GABAA receptors provide a possible mechanism for the known anti-epileptic effects of α-asarone. It also suggests that α-asarone could benefit patients with cough possibly through inhibiting a Na(+) channel subtype to inhibit peripheral and/or central sensitization of cough reflexes.
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Affiliation(s)
- Ze-Jun Wang
- Department of Anatomy, College of Medicine, Howard University Washington, DC, USA
| | - Simon R Levinson
- Department of Physiology and Biophysics, University of Colorado Denver School of Medicine Aurora, CO, USA
| | - Liqin Sun
- Department of Anatomy, College of Medicine, Howard University Washington, DC, USA
| | - Thomas Heinbockel
- Department of Anatomy, College of Medicine, Howard University Washington, DC, USA
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Steinhoff MS, von Mentzer B, Geppetti P, Pothoulakis C, Bunnett NW. Tachykinins and their receptors: contributions to physiological control and the mechanisms of disease. Physiol Rev 2014; 94:265-301. [PMID: 24382888 DOI: 10.1152/physrev.00031.2013] [Citation(s) in RCA: 413] [Impact Index Per Article: 41.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
The tachykinins, exemplified by substance P, are one of the most intensively studied neuropeptide families. They comprise a series of structurally related peptides that derive from alternate processing of three Tac genes and are expressed throughout the nervous and immune systems. Tachykinins interact with three neurokinin G protein-coupled receptors. The signaling, trafficking, and regulation of neurokinin receptors have also been topics of intense study. Tachykinins participate in important physiological processes in the nervous, immune, gastrointestinal, respiratory, urogenital, and dermal systems, including inflammation, nociception, smooth muscle contractility, epithelial secretion, and proliferation. They contribute to multiple diseases processes, including acute and chronic inflammation and pain, fibrosis, affective and addictive disorders, functional disorders of the intestine and urinary bladder, infection, and cancer. Neurokinin receptor antagonists are selective, potent, and show efficacy in models of disease. In clinical trials there is a singular success: neurokinin 1 receptor antagonists to treat nausea and vomiting. New information about the involvement of tachykinins in infection, fibrosis, and pruritus justifies further trials. A deeper understanding of disease mechanisms is required for the development of more predictive experimental models, and for the design and interpretation of clinical trials. Knowledge of neurokinin receptor structure, and the development of targeting strategies to disrupt disease-relevant subcellular signaling of neurokinin receptors, may refine the next generation of neurokinin receptor antagonists.
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