1
|
Myall KJ, Cho PSP, Birring S. What causes cough in pulmonary fibrosis, and how should we treat it? Curr Opin Pulm Med 2024:00063198-990000000-00170. [PMID: 38913018 DOI: 10.1097/mcp.0000000000001087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/25/2024]
Abstract
PURPOSE OF REVIEW To review the current understanding of the impact, mechanisms and treatments for cough in patients with interstitial lung disease (ILD). Evidence suggests that cough is a prevalent symptom in patients with ILD and has a significant impact on patients. RECENT FINDINGS There is increasing interest in the role of cough hypersensitivity as seen in chronic refractory cough in patients with ILD, and encouraging recent results suggest that ILD-associated cough responds to opiate therapy. SUMMARY Understanding the aetiology of cough in patients with ILD is crucial to continue to develop therapies which might be effective in reducing cough and increasing quality of life.
Collapse
Affiliation(s)
- Katherine J Myall
- Department of Respiratory Medicine, King's College Hospital
- King's College London, London, UK
| | - Peter S P Cho
- Department of Respiratory Medicine, King's College Hospital
- King's College London, London, UK
| | - Surinder Birring
- Department of Respiratory Medicine, King's College Hospital
- King's College London, London, UK
| |
Collapse
|
2
|
Zouki JJ, Eapen V, Efron D, Maxwell A, Corp DT, Silk TJ. Functional brain networks associated with the urge for action: Implications for pathological urge. Neurosci Biobehav Rev 2024; 163:105779. [PMID: 38936563 DOI: 10.1016/j.neubiorev.2024.105779] [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: 10/28/2023] [Revised: 05/26/2024] [Accepted: 06/20/2024] [Indexed: 06/29/2024]
Abstract
Tics in Tourette syndrome (TS) are often preceded by sensory urges that drive the motor and vocal symptoms. Many everyday physiological behaviors are associated with sensory phenomena experienced as an urge for action, which may provide insight into the neural correlates of this pathological urge to tic that remains elusive. This study aimed to identify a brain network common to distinct physiological behaviors in healthy individuals, and in turn, examine whether this network converges with a network we previously localized in TS, using novel 'coordinate network mapping' methods. Systematic searches were conducted to identify functional neuroimaging studies reporting correlates of the urge to micturate, swallow, blink, or cough. Using activation likelihood estimation meta-analysis, we identified an 'urge network' common to these physiological behaviors, involving the bilateral insula/claustrum/inferior frontal gyrus/supplementary motor area, mid-/anterior- cingulate cortex (ACC), right postcentral gyrus, and left thalamus/precentral gyrus. Similarity between the urge and TS networks was identified in the bilateral insula, ACC, and left thalamus/claustrum. The potential role of the insula/ACC as nodes in the network for bodily representations of the urge to tic are discussed.
Collapse
Affiliation(s)
- Jade-Jocelyne Zouki
- Centre for Social and Early Emotional Development and School of Psychology, Deakin University, Geelong, VIC 3220, Australia.
| | - Valsamma Eapen
- Discipline of Psychiatry and Mental Health, UNSW School of Clinical Medicine, University of New South Wales, Kensington, NSW 2052, Australia
| | - Daryl Efron
- Department of Paediatrics, The University of Melbourne, Melbourne, VIC 3010, Australia; Murdoch Children's Research Institute, Melbourne, VIC 3052, Australia
| | - Amanda Maxwell
- Discipline of Psychiatry and Mental Health, UNSW School of Clinical Medicine, University of New South Wales, Kensington, NSW 2052, Australia
| | - Daniel T Corp
- Centre for Social and Early Emotional Development and School of Psychology, Deakin University, Geelong, VIC 3220, Australia; Turku Brain and Mind Center, Clinical Neurosciences, University of Turku, Turku, FI-20014, Finland
| | - Timothy J Silk
- Centre for Social and Early Emotional Development and School of Psychology, Deakin University, Geelong, VIC 3220, Australia; Murdoch Children's Research Institute, Melbourne, VIC 3052, Australia
| |
Collapse
|
3
|
Guilleminault L, Grassin-Delyle S, Mazzone SB. Drugs Targeting Cough Receptors: New Therapeutic Options in Refractory or Unexplained Chronic Cough. Drugs 2024:10.1007/s40265-024-02047-y. [PMID: 38904926 DOI: 10.1007/s40265-024-02047-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/06/2024] [Indexed: 06/22/2024]
Abstract
Refractory chronic cough is a disabling disease with very limited therapeutic options. A better understanding of cough pathophysiology has led to the development of emerging drugs targeting cough receptors. Recent strides have illuminated novel therapeutic avenues, notably centred on modulating transient receptor potential (TRP) channels, purinergic receptors, and neurokinin receptors. By modulating these receptors, the goal is to intervene in the sensory pathways that trigger cough reflexes, thereby providing relief without compromising vital protective mechanisms. These innovative pharmacotherapies hold promise for improvement of refractory chronic cough by offering improved efficacy and potentially mitigating adverse effects associated with current recommended treatments. A deeper comprehension of their precise mechanisms of action and clinical viability is imperative for optimising therapeutic interventions and elevating patient care standards in respiratory health. This review delineates the evolving landscape of drug development in this domain, emphasising the significance of these advancements in reshaping the paradigm of cough management.
Collapse
Affiliation(s)
- Laurent Guilleminault
- Toulouse Institute for Infectious and Inflammatory Diseases (Infinity), INSERM UMR1291, CNRS UMR5051, University Toulouse III, 31024, Toulouse, France.
- Department of Respiratory Medicine, Faculty of Medicine, Hôpital Larrey, Toulouse University Hospital, 24 chemin de Pouvourville, 31059, Toulouse, France.
| | - Stanislas Grassin-Delyle
- Exhalomics®, Hôpital Foch, Suresnes, France
- Département de Biotechnologie de la Santé, Université Paris-Saclay, UVSQ, INSERM, Infection et inflammation (2I), U1173, Montigny le Bretonneux, France
| | - Stuart B Mazzone
- Department of Anatomy and Physiology, University of Melbourne, Melbourne, VIC, Australia
| |
Collapse
|
4
|
Moe AAK, Singh N, Dimmock M, Cox K, McGarvey L, Chung KF, McGovern AE, McMahon M, Richards AL, Farrell MJ, Mazzone SB. Brainstem processing of cough sensory inputs in chronic cough hypersensitivity. EBioMedicine 2024; 100:104976. [PMID: 38244293 PMCID: PMC10831188 DOI: 10.1016/j.ebiom.2024.104976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/09/2023] [Accepted: 01/05/2024] [Indexed: 01/22/2024] Open
Abstract
BACKGROUND Chronic cough is a prevalent and difficult to treat condition often accompanied by cough hypersensitivity, characterised by cough triggered from exposure to low level sensory stimuli. The mechanisms underlying cough hypersensitivity may involve alterations in airway sensory nerve responsivity to tussive stimuli which would be accompanied by alterations in stimulus-induced brainstem activation, measurable with functional magnetic resonance imaging (fMRI). METHODS We investigated brainstem responses during inhalation of capsaicin and adenosine triphosphate (ATP) in 29 participants with chronic cough and 29 age- and sex-matched controls. Psychophysical testing was performed to evaluate individual sensitivities to inhaled stimuli and fMRI was used to compare neural activation in participants with cough and control participants while inhaling stimulus concentrations that evoked equivalent levels of urge-to-cough sensation. FINDINGS Participants with chronic cough were significantly more sensitive to inhaled capsaicin and ATP and showed a change in relationship between urge-to-cough perception and cough induction. When urge-to-cough levels were matched, participants with chronic cough displayed significantly less neural activation in medullary regions known to integrate airway sensory inputs. By contrast, neural activations did not differ significantly between the two groups in cortical brain regions known to encode cough sensations whereas activation in a midbrain region of participants with chronic cough was significantly increased compared to controls. INTERPRETATION Cough hypersensitivity in some patients may occur in brain circuits above the level of the medulla, perhaps involving midbrain regions that amplify ascending sensory signals or change the efficacy of central inhibitory control systems that ordinarily serve to filter sensory inputs. FUNDING Supported in part by a research grant from Investigator-Initiated Studies Program of Merck Sharp & Dohme Pty Ltd. The opinions expressed in this paper are those of the authors and do not necessarily represent those of Merck Sharp & Dohme (Australia) Pty Ltd.
Collapse
Affiliation(s)
- Aung Aung Kywe Moe
- Department of Anatomy and Physiology, University of Melbourne, Parkville, VIC, Australia; Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, VIC, Australia
| | - Nabita Singh
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, VIC, Australia
| | - Matthew Dimmock
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, VIC, Australia; School of Allied Health Professions, Keele University, Staffordshire, UK
| | - Katherine Cox
- Centre for Human Psychopharmacology, Swinburne University, Australia
| | - Lorcan McGarvey
- Wellcome-Wolfson Institute for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, UK
| | - Kian Fan Chung
- Experimental Studies Unit, National Heart & Lung Institute, Imperial College London, UK; Department of Respiratory Medicine, Royal Brompton and Harefield Hospital, London, UK
| | - Alice E McGovern
- Department of Anatomy and Physiology, University of Melbourne, Parkville, VIC, Australia
| | - Marcus McMahon
- Department of Respiratory and Sleep Medicine, Austin Hospital, Heidelberg, Australia
| | - Amanda L Richards
- Department of Otolaryngology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, VIC, Australia; Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia
| | - Stuart B Mazzone
- Department of Anatomy and Physiology, University of Melbourne, Parkville, VIC, Australia.
| |
Collapse
|
5
|
Xu T, Chen Z, Zhan C, Zhan W, Yi F, Lai K. Profile of cough triggers and their relationship with capsaicin cough sensitivity in chronic cough. Ther Adv Respir Dis 2024; 18:17534666231225562. [PMID: 38343122 PMCID: PMC10860467 DOI: 10.1177/17534666231225562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 12/13/2023] [Indexed: 02/15/2024] Open
Abstract
BACKGROUND Cough hypersensitivity is an important part of the neurophysiology of cough, which presents with increased cough response to a lower level of stimuli or triggers. Classification of stimuli might bring about additional insight into the underlying mechanisms and management. OBJECTIVES This study investigated the profile of cough triggers in chronic cough patients and their relationship with capsaicin cough sensitivity. DESIGN This was a cross-sectional observational study. METHODS We enrolled patients with different causes of chronic cough from 2006 to 2021. Cough triggers were defined as cough response to chemical triggers, mechanical triggers, meal triggers, or thermal trigger. Cough sensitivity to capsaicin was evaluated by the capsaicin challenge test, which was expressed as the lowest concentration of capsaicin inducing 5 or more coughing (C5). RESULTS Among 1211 patients with chronic cough, 1107 (91.4%) patients reported at least one cough trigger. Chemical triggers (66.9%) were the most common cough triggers, followed by thermal exposure (50.6%), mechanical triggers (48.2%), and meal triggers (21.2%). There was no difference in the proportion of chemical triggers among different etiologies. Patients with refractory chronic cough reported the highest prevalence of cough triggers (97.1%). A higher number of meal triggers (34.9%) was associated with gastroesophageal reflux-related cough, and meal triggers and mechanical triggers were more common in refractory chronic cough. Among 254 patients who completed capsaicin challenge test, both the number of total triggers and the number of chemical triggers had a significant but mild correlation with capsaicin cough sensitivity. CONCLUSION Cough hypersensitivity as reflected by a variety of cough triggers is a common feature in chronic cough patients, but different etiologies present specific profiles of cough triggers, which could not be evaluated comprehensively by capsaicin cough sensitivity.
Collapse
Affiliation(s)
- Tingting Xu
- Guangzhou Institute of Respiratory Health, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University
| | - Zhiyin Chen
- Guangzhou Institute of Respiratory Health, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University
| | - Chen Zhan
- Guangzhou Institute of Respiratory Health, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University
| | - Wenzhi Zhan
- Guangzhou Institute of Respiratory Health, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University
| | - Fang Yi
- Guangzhou Institute of Respiratory Health, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University
| | - Kefang Lai
- Guangzhou Institute of Respiratory Health, State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, National Center for Respiratory Medicine, the First Affiliated Hospital of Guangzhou Medical University, 151 Yanjiang Road, Guangzhou 510120, China
| |
Collapse
|
6
|
Guo L, Wu C, Chen C, Zhang B, Wu J, Xie Y, Gui P. Anodal transcranial direct current stimulation over the right primary somatosensory cortex increases cough reflex sensitivity: a pilot randomised controlled crossover trial. ERJ Open Res 2023; 9:00238-2023. [PMID: 37850211 PMCID: PMC10577598 DOI: 10.1183/23120541.00238-2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 08/15/2023] [Indexed: 10/19/2023] Open
Abstract
Background The cough reflex is a protective reflex of the human body. Increases or decreases in cough reflex sensitivity may be related to chronic cough, aspiration pneumonia and other diseases. The right primary somatosensory cortex (RS1) is the main activation centre for the urge to cough. Here, we discuss the effects of transcranial direct current stimulation (tDCS) of RS1 on the cough reflex and urge to cough. In addition, we explored the role of the left dorsolateral prefrontal cortex (lDLPFC) in cough using tDCS. Methods 24 healthy young adults completed this pilot randomised controlled crossover experiment. Each person was tested three times, receiving, in random order, anodal tDCS of RS1 or lDLPFC or sham stimulation. The current intensity was set to 2 mA, the stimulation time was 30 min and the interval between any two stimuli was ≥1 week. After each intervention, the citric acid cough challenge test was used immediately to assess the urge to cough and cough reflex sensitivity. Results The cough reflex thresholds, expressed as LogC2 and LogC5, were significantly reduced after RS1 anodal stimulation compared to sham stimulation, accompanied by increased urge-to-cough sensitivity (urge-to-cough log-log slope 1.19±0.40 point·L·g-1 versus 0.92±0.33 point·L·g-1, p=0.001), but the threshold for the urge to cough did not change significantly. There were no significant changes in the urge to cough and cough reflex sensitivity after tDCS anodal lDLPFC stimulation. Conclusion Anodal tDCS stimulation of the RS1 can increase urge-to-cough sensitivity and reduce cough reflex threshold. The effects of tDCS on cough reflex, as well as the underlying mechanisms driving those effects, should be explored further.
Collapse
Affiliation(s)
- Liya Guo
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Chunwei Wu
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Chen Chen
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Bo Zhang
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Jian Wu
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
| | - Ying Xie
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Y. Xie and P. Gui contributed equally to this article as lead authors and supervised the work
| | - Peijun Gui
- Department of Rehabilitation Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Y. Xie and P. Gui contributed equally to this article as lead authors and supervised the work
| |
Collapse
|
7
|
Schmitt JE. CHEST Meets Brain: Understanding Chronic Cough Requires Interdisciplinary Thinking. Chest 2023; 164:13-14. [PMID: 37423690 DOI: 10.1016/j.chest.2023.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 04/01/2023] [Indexed: 07/11/2023] Open
Affiliation(s)
- J Eric Schmitt
- Department of Radiology and Psychiatry, Division of Neuroradiology, Hospital of the University of Pennsylvania, Philadelphia, PA.
| |
Collapse
|
8
|
Molot J, Sears M, Anisman H. Multiple Chemical Sensitivity: It's time to catch up to the science. Neurosci Biobehav Rev 2023; 151:105227. [PMID: 37172924 DOI: 10.1016/j.neubiorev.2023.105227] [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: 06/07/2022] [Accepted: 05/06/2023] [Indexed: 05/15/2023]
Abstract
Multiple chemical sensitivity (MCS) is a complex medical condition associated with low dose chemical exposures. MCS is characterized by diverse features and common comorbidities, including fibromyalgia, cough hypersensitivity, asthma, and migraine, and stress/anxiety, with which the syndrome shares numerous neurobiological processes and altered functioning within diverse brain regions. Predictive factors linked to MCS comprise genetic influences, gene-environment interactions, oxidative stress, systemic inflammation, cell dysfunction, and psychosocial influences. The development of MCS may be attributed to the sensitization of transient receptor potential (TRP) receptors, notably TRPV1 and TRPA1. Capsaicin inhalation challenge studies demonstrated that TRPV1 sensitization is manifested in MCS, and functional brain imaging studies revealed that TRPV1 and TRPA1 agonists promote brain-region specific neuronal variations. Unfortunately, MCS has often been inappropriately viewed as stemming exclusively from psychological disturbances, which has fostered patients being stigmatized and ostracized, and often being denied accommodation for their disability. Evidence-based education is essential to provide appropriate support and advocacy. Greater recognition of receptor-mediated biological mechanisms should be incorporated in laws, and regulation of environmental exposures.
Collapse
Affiliation(s)
- John Molot
- Family Medicine, University of Ottawa Faculty of Medicine, Ottawa ON Canada; Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Neuroscience, Carleton University, Ottawa Canada.
| | - Margaret Sears
- Family Medicine, University of Ottawa Faculty of Medicine, Ottawa ON Canada; Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Neuroscience, Carleton University, Ottawa Canada.
| | - Hymie Anisman
- Family Medicine, University of Ottawa Faculty of Medicine, Ottawa ON Canada; Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Neuroscience, Carleton University, Ottawa Canada.
| |
Collapse
|
9
|
Koskela HO, Kaulamo JT, Lätti AM. Cough Sensitivity to Several External Triggers is Associated with Multiple Non-respiratory Symptoms. Lung 2023:10.1007/s00408-023-00622-w. [PMID: 37156984 DOI: 10.1007/s00408-023-00622-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 04/27/2023] [Indexed: 05/10/2023]
Abstract
PURPOSE Enhanced responsiveness to external triggers is thought to reflect hypersensitivity of the cough reflex. It may involve an enhanced sensitivity of the afferent nerves in the airways and/or an abnormal processing of the afferent information by the central nervous system (CNS). The CNS processing of cough has been shown to involve the same regions as those in symptom amplification, a phenomenon that often manifests as multiple symptoms. The main purpose of the present study was to define whether the presence of several cough triggers is associated with multiple symptoms. METHODS 2131 subjects with current cough responding to two email surveys filled in a comprehensive questionnaire about social background, lifestyle, general health, doctors' diagnoses and visits, symptoms, and medication. Multiple symptoms was defined as three or more non-respiratory, non-mental symptoms. RESULTS A carefully controlled multiple regression analysis revealed that the number of cough triggers was the only cough characteristic associating with multiple non-respiratory, non-mental symptoms [aOR 1.15 (1.12-1.19) per one trigger, p < 0.001]. Among the 268 subjects with current cough both in the first survey and in the follow-up survey 12 months later, the repeatability of the trigger sum was good with an intraclass correlation coefficient of 0.80 (0.75-0.84). CONCLUSION The association between the number of the cough triggers and multiple symptoms suggests that the CNS component of cough hypersensitivity may be a manifestation of non-specific alteration in the CNS interpretation of various body sensations. The number of cough triggers is a repeatable measure of cough sensitivity.
Collapse
Affiliation(s)
- Heikki O Koskela
- School of Medicine, University of Eastern Finland, Kuopio, Finland.
- Unit for Medicine and Clinical Research, Pulmonary Division, Kuopio University Hospital, PL 100, 70029 KYS, Kuopio, Finland.
| | | | - Anne M Lätti
- Unit for Medicine and Clinical Research, Pulmonary Division, Kuopio University Hospital, PL 100, 70029 KYS, Kuopio, Finland
| |
Collapse
|
10
|
Arinze JT, Vinke EJ, Verhamme KMC, de Ridder MAJ, Stricker B, Ikram MK, Brusselle G, Vernooij MW. Chronic Cough-Related Differences in Brain Morphometry in Adults: A Population-Based Study. Chest 2023:S0012-3692(23)00187-3. [PMID: 36781103 DOI: 10.1016/j.chest.2023.02.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 02/02/2023] [Accepted: 02/06/2023] [Indexed: 02/13/2023] Open
Abstract
BACKGROUND Individuals with cough hypersensitivity have increased central neural responses to tussive stimuli, which may result in maladaptive morphometric changes in the central cough processing systems. RESEARCH QUESTION Are the volumes of the brain regions implicated in cough hypersensitivity different in adults with chronic cough compared with adults without chronic cough? STUDY DESIGN AND METHODS Between 2009 and 2014, participants in the Rotterdam Study, a population-based cohort, underwent brain MRI and were interviewed for chronic cough, which was defined as daily coughing for at least 3 months. Regional brain volumes were quantified with the use of parcellation software. Based on literature review, we identified and studied seven brain regions that previously had been associated with altered functional brain activity in chronic cough. The relationship between chronic cough and regional brain volumes was investigated with the use of multivariable regression models. RESULTS Chronic cough was prevalent in 9.6% (No. = 349) of the 3,620 study participants (mean age, 68.5 ± 9.0 years; 54.6% women). Participants with chronic cough had significantly smaller anterior cingulate cortex volume than participants without chronic cough (mean difference, -126.16 mm3; 95% CI, -245.67 to -6.66; P = .039). Except for anterior cingulate cortex, there were no significant difference in the volume of other brain regions based on chronic cough status. The volume difference in the anterior cingulate cortex was more pronounced in the left hemisphere (mean difference, -88.11 mm3; 95% CI, -165.16 to -11.06; P = .025) and in men (mean difference, -242.58 mm3; 95% CI, -428.60 to -56.55; P = .011). INTERPRETATION Individuals with chronic cough have a smaller volume of the anterior cingulate cortex, which is a brain region involved in cough suppression. CLINICAL TRIAL REGISTRATION The Netherlands National Trial Registry (NTR; www.trialregister.nl) and the World Health Organization's International Clinical Trials Registry Platform (ICTRP; www.who.int/ictrp/network/primary/en/) under the joint catalogue number NTR6831.
Collapse
Affiliation(s)
- Johnmary T Arinze
- Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium; Department of Medical Informatics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Elisabeth J Vinke
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Radiology and Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Katia M C Verhamme
- Department of Medical Informatics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Maria A J de Ridder
- Department of Medical Informatics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Bruno Stricker
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - M K Ikram
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Guy Brusselle
- Department of Respiratory Medicine, Ghent University Hospital, Ghent, Belgium; Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Respiratory Medicine, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Meike W Vernooij
- Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Radiology and Nuclear Medicine, Erasmus Medical Center, Rotterdam, The Netherlands.
| |
Collapse
|
11
|
Mini-review: Hypertussivity and allotussivity in chronic cough endotypes. Neurosci Lett 2023; 792:136934. [PMID: 36309151 DOI: 10.1016/j.neulet.2022.136934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 10/12/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022]
Abstract
In recent years our understanding of the neurophysiological basis of cough has increased substantially. In conjunction, concepts around the drivers of chronic coughing in patients have also significantly evolved. Increasingly it is recognised that dysregulation of the neuronal pathways mediating cough play an important role in certain phenotypes of chronic cough and therefore pathological processes affecting the nervous system are likely to represent key endotypes in patients. Taking inspiration from the study of neuropathic pain, the term hypertussia has been employed to describe the phenomenon of abnormal excessive coughing in response to airway irritation and allotussia to describe coughing in response to stimuli not normally provoking cough. This review aims to summarise current clinical evidence supporting a role for the hyperexcitability of neuronal pathways contributing to chronic coughing and suggest how these might align with the clinical features observed in patients.
Collapse
|
12
|
Plevkova J, Brozmanova M, Matloobi A, Poliacek I, Honetschlager J, Buday T. Animal models of cough. Respir Physiol Neurobiol 2021; 290:103656. [PMID: 33781930 DOI: 10.1016/j.resp.2021.103656] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 03/16/2021] [Accepted: 03/21/2021] [Indexed: 01/10/2023]
Abstract
Cough is a vital airway reflex that keeps the respiratory tract wisely protected. It is also a sign of many diseases of the respiratory system and it may become a disease in its own right. Even though the efficacy of antitussive compounds is extensively studied in animal models with promising results, the treatment of pathological cough in humans is insufficient at the moment. The limited translational potential of animal models used to study cough causes, mechanisms and possible therapeutic targets stems from multiple sources. First of all, cough induced in the laboratory by mechanical or chemical stimuli is far from natural cough present in human disease. The main objective of this review is to provide a comprehensive summary of animal models currently used in cough research and to address their advantages and disadvantages. We also want to encourage cough researchers to call for precision is research by addressing the sex bias which has existed in basic cough research for decades and discuss the role of specific pathogen-free (SPF) animals.
Collapse
Affiliation(s)
- Jana Plevkova
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Department of Pathophysiology, Martin, Slovakia
| | - Mariana Brozmanova
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Department of Pathophysiology, Martin, Slovakia
| | - Alireza Matloobi
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Department of Pathophysiology, Martin, Slovakia
| | - Ivan Poliacek
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Department of Biophysics, Martin, Slovakia
| | - Jan Honetschlager
- Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Tomas Buday
- Comenius University in Bratislava, Jessenius Faculty of Medicine in Martin, Department of Pathophysiology, Martin, Slovakia.
| |
Collapse
|
13
|
Dual Tasking Influences Cough Reflex Outcomes in Adults with Parkinson's Disease: A Controlled Study. Dysphagia 2021; 36:959-973. [PMID: 33387000 DOI: 10.1007/s00455-020-10223-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 11/24/2020] [Indexed: 10/22/2022]
Abstract
Coughing is an essential airway protective reflex. In healthy young adults, cough somatosensation changes when attention is divided (dual tasking). Whether the same is true in populations at risk of aspiration remains unknown. We present findings from a controlled study testing the effects of divided attention (via a dual-task paradigm) on measures of reflex cough in Parkinson's disease. Volunteers with Parkinson's disease (n = 14, age = 43-79 years) and 14 age-matched controls underwent five blocks of capsaicin-induced cough challenges. Within each block, capsaicin ranging from 0 to 200 μM was presented in a randomized order. Two blocks consisted of cough testing only (single task), and two blocks consisted of cough testing with simultaneous tone counting (dual task). Finally, participants completed a suppressed cough task. Measures of cough motor response, self-reported urge to cough, cough frequency, and cough airflow were collected. Historical data from healthy young adults was included for comparison. Between-group analyses revealed no differences between single- and dual-cough-task responses. However, post hoc analysis revealed a significant relationship between dual-task errors and cough frequency that was strongest in people with Parkinson's disease [p = 0.004, r2 = 0.52]. Specifically, greater errors were associated with fewer reflexive coughs. Unlike healthy participants, participants with Parkinson's disease did not change the number of coughs between the single-, dual-, and suppressed-task conditions [p > 0.05]. When distracted, people with Parkinson's disease may prioritize coughing differently than healthy controls. Abnormal cortical resource allocation may be a mechanism involved in aspiration in this population.
Collapse
|
14
|
Behrens R, McGovern AE, Farrell MJ, Moe AAK, Mazzone SB. Mini Review: Central Organization of Airway Afferent Nerve Circuits. Neurosci Lett 2020; 744:135604. [PMID: 33387662 DOI: 10.1016/j.neulet.2020.135604] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 12/16/2020] [Accepted: 12/21/2020] [Indexed: 10/22/2022]
Abstract
Airway afferents monitor the local chemical and physical micro-environments in the airway wall and lungs and send this information centrally to regulate neural circuits involved in setting autonomic tone, evoking reflex and volitional respiratory motor outflows, encoding perceivable sensations and contributing to higher order cognitive processing. In this mini-review we present a current overview of the central wiring of airway afferent circuits in the brainstem and brain, highlighting recent discoveries that augment our understanding of airway sensory processing. We additionally explore how advances in describing the molecular diversity of airway afferents may influence future research efforts aimed at defining central mesoscale connectivity of airway afferent pathways. A refined understanding of how functionally distinct airway afferent pathways are organized in the brain will provide deeper insight into the physiology of airway afferent-evoked responses and may foster opportunities for targeted modulation of specific pathways involved in disease.
Collapse
Affiliation(s)
- Robert Behrens
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| | - Alice E McGovern
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| | - Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia; Monash Biomedical Imaging, Monash University, Clayton, Australia
| | - Aung Aung Kywe Moe
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| | - Stuart B Mazzone
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia.
| |
Collapse
|
15
|
Descending Modulation of Laryngeal Vagal Sensory Processing in the Brainstem Orchestrated by the Submedius Thalamic Nucleus. J Neurosci 2020; 40:9426-9439. [PMID: 33115928 DOI: 10.1523/jneurosci.2430-20.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 11/21/2022] Open
Abstract
The nodose and jugular vagal ganglia supply sensory innervation to the airways and lungs. Jugular vagal airway sensory neurons wire into a brainstem circuit with ascending projections into the submedius thalamic nucleus (SubM) and ventrolateral orbital cortex (VLO), regions known to regulate the endogenous analgesia system. Here we investigate whether the SubM-VLO circuit exerts descending regulation over airway vagal reflexes in male and female rats using a range of neuroanatomical tracing, reflex physiology, and chemogenetic techniques. Anterograde and retrograde neuroanatomical tracing confirmed the connectivity of the SubM and VLO. Laryngeal stimulation in anesthetized rats reduced respiration, a reflex that was potently inhibited by activation of SubM. Conversely, inhibition of SubM potentiated laryngeal reflex responses, while prior lesions of VLO abolished the effects of SubM stimulation. In conscious rats, selective chemogenetic activation of SubM neurons specifically projecting to VLO significantly inhibited respiratory responses evoked by inhalation of the nociceptor stimulant capsaicin. Jugular vagal inputs to SubM via the medullary paratrigeminal nucleus were confirmed using anterograde transsynaptic conditional herpes viral tracing. Respiratory responses evoked by microinjections of capsaicin into the paratrigeminal nucleus were significantly attenuated by SubM stimulation, whereas those evoked via the nucleus of the solitary tract were unaltered. These data suggest that jugular vagal sensory pathways input to a nociceptive thalamocortical circuit capable of regulating jugular sensory processing in the medulla. This circuit organization suggests an intersection between vagal sensory pathways and the endogenous analgesia system, potentially important for understanding vagal sensory processing in health and mechanisms of hypersensitivity in disease.SIGNIFICANCE STATEMENT Jugular vagal sensory pathways are increasingly recognized for their important role in defensive respiratory responses evoked from the airways. Jugular ganglia neurons wire into a central circuit that is notable for overlapping with somatosensory processing networks in the brain rather than the viscerosensory circuits in receipt of inputs from the nodose vagal ganglia. Here we demonstrate a novel and functionally relevant example of intersection between vagal and somatosensory processing in the brain. The findings of the study offer new insights into interactions between vagal and spinal sensory processing, including the medullary targets of the endogenous analgesia system, and offer new insights into the central processes involved in airway defense in health and disease.
Collapse
|
16
|
Farrell MJ, Bautista TG, Liang E, Azzollini D, Egan GF, Mazzone SB. Evidence for multiple bulbar and higher brain circuits processing sensory inputs from the respiratory system in humans. J Physiol 2020; 598:5771-5787. [DOI: 10.1113/jp280220] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 09/02/2020] [Indexed: 12/13/2022] Open
Affiliation(s)
- Michael J. Farrell
- Departmental of Medical Imaging and Radiation Sciences Monash University Clayton VIC Australia
- Monash Biomedical Imaging Monash University Clayton VIC Australia
| | - Tara G. Bautista
- Department of Anatomy and Neuroscience University of Melbourne Parkville Victoria Australia
| | - Emma Liang
- Monash Biomedical Imaging Monash University Clayton VIC Australia
| | - Damian Azzollini
- Monash Biomedical Imaging Monash University Clayton VIC Australia
| | - Gary F. Egan
- Monash Biomedical Imaging Monash University Clayton VIC Australia
- School of Psychological Sciences Monash University Clayton VIC Australia
- ARC Centre of Excellence for Integrative Brain Function Monash University Clayton VIC Australia
| | - Stuart B. Mazzone
- Department of Anatomy and Neuroscience University of Melbourne Parkville Victoria Australia
| |
Collapse
|
17
|
Abubakar AB, Bautista TG, Dimmock MR, Mazzone SB, Farrell MJ. Behavioral and Regional Brain Responses to Inhalation of Capsaicin Modified by Painful Conditioning in Humans. Chest 2020; 159:1136-1146. [PMID: 32926869 DOI: 10.1016/j.chest.2020.08.2105] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 08/06/2020] [Accepted: 08/27/2020] [Indexed: 10/23/2022] Open
Abstract
BACKGROUND Cough is a defense mechanism that protects the airways and lungs in response to airway irritation. The sensory neurons involved in detecting airway irritants and the neural pathways mediating cough share similarities with those that encode pain from the body. Painful conditioning stimuli applied to one body site are known to reduce the perception of pain at another. However, whether the neural regulation of cough is influenced by painful stimuli is not known. RESEARCH QUESTION What are the behavioral and neural outcomes of painful conditioning stimuli on urge-to-cough (UTC) and cough evoked by inhaled capsaicin? STUDY DESIGN AND METHODS Sixteen healthy participants underwent psychophysical testing and functional MRI while completing a series of capsaicin inhalations to induce UTC and cough. The responses associated with capsaicin inhalation without pain were compared with those after the application of painful conditioning stimuli. RESULTS Significant decreases were seen behaviorally of 18.7% ± 17.3% (P < .001) and 47.0% ± 30.8% (P < .001) in participants' UTC ratings and cough frequencies, respectively, during the application of pain. UTC ratings were reduced by 24.2% ± 36.5% (P < .005) and increased by 67% ± 40% (P < .001) for capsaicin and saline inhalation, respectively, during the scanning session. Painful conditioning stimuli were associated with widespread decreases in regional brain responses to capsaicin inhalation (P < .001). Several brain regions showed levels of reduced activation attributable to painful conditioning that correlated with related changes in behavioral responses during scanning (R2 = 0.53). INTERPRETATION Pain-related decreases of cough and UTC are accompanied by widespread changes in brain activity during capsaicin inhalation, suggesting that pain can modify the central processing of inputs arising from the airways. A mechanistic understanding of how cough and pain processing interact within the brain may help develop more effective therapies to reduce unwanted coughing.
Collapse
Affiliation(s)
- Abubakar B Abubakar
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia
| | - Tara G Bautista
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia
| | - Matthew R Dimmock
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia
| | - Stuart B Mazzone
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Australia.
| | - Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia; Monash Biomedical Imaging, Monash University, Clayton, Australia
| |
Collapse
|
18
|
Singh N, Driessen AK, McGovern AE, Moe AAK, Farrell MJ, Mazzone SB. Peripheral and central mechanisms of cough hypersensitivity. J Thorac Dis 2020; 12:5179-5193. [PMID: 33145095 PMCID: PMC7578480 DOI: 10.21037/jtd-2020-icc-007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Chronic cough is a difficult to treat symptom of many respiratory and some non-respiratory diseases, indicating that varied pathologies can underpin the development of chronic cough. However, clinically and experimentally it has been useful to collate these different pathological processes into the single unifying concept of cough hypersensitivity. Cough hypersensitivity syndrome is reflected by troublesome cough often precipitated by levels of stimuli that ordinarily don't cause cough in healthy people, and this appears to be a hallmark feature in many patients with chronic cough. Accordingly, a strong argument has emerged that changes in the excitability and/or normal regulation of the peripheral and central neural circuits responsible for cough are instrumental in establishing cough hypersensitivity and for causing excessive cough in disease. In this review, we explore the current peripheral and central neural mechanisms that are believed to be involved in altered cough sensitivity and present possible links to the mechanism of action of novel therapies that are currently undergoing clinical trials for chronic cough.
Collapse
Affiliation(s)
- Nabita Singh
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia
| | - Alexandria K. Driessen
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| | - Alice E. McGovern
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| | - Aung Aung Kywe Moe
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| | - Michael J. Farrell
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia
- Monash Biomedical Imaging, Monash University, Clayton, Australia
| | - Stuart B. Mazzone
- Department of Anatomy and Neuroscience, School of Biomedical Science, The University of Melbourne, Parkville, Australia
| |
Collapse
|
19
|
Driessen AK, McGovern AE, Behrens R, Moe AAK, Farrell MJ, Mazzone SB. A role for neurokinin 1 receptor expressing neurons in the paratrigeminal nucleus in bradykinin-evoked cough in guinea-pigs. J Physiol 2020; 598:2257-2275. [PMID: 32237239 DOI: 10.1113/jp279644] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 03/16/2020] [Indexed: 12/21/2022] Open
Abstract
KEY POINTS Airway projecting sensory neurons arising from the jugular vagal ganglia terminate centrally in the brainstem paratrigeminal nucleus, synapsing upon neurons expressing the neurokinin 1 receptor. This study aimed to assess the involvement of paratrigeminal neurokinin 1 receptor neurons in the regulation of cough, breathing and airway defensive responses. Lesioning neurokinin 1 receptor expressing paratrigeminal neurons significantly reduced cough evoked by inhaled bradykinin but not inhaled ATP or tracheal mechanical stimulation. The reduction in bradykinin-evoked cough was not accompanied by changes in baseline or evoked respiratory variables (e.g. frequency, volume or timing), animal avoidance behaviours or the laryngeal apnoea reflex. These findings warrant further investigations into targeting the jugular ganglia and paratrigeminal nucleus as a therapy for treating cough in disease. ABSTRACT Jugular vagal ganglia sensory neurons innervate the large airways and are thought to mediate cough and associated perceptions of airway irritations to a range of chemical irritants. The central terminals of jugular sensory neurons lie within the brainstem paratrigeminal nucleus, where postsynaptic neurons can be differentiated based on the absence or presence of the neurokinin 1 (NK1) receptor. Therefore, in the present study, we set out to test the hypothesis that NK1 receptor expressing paratrigeminal neurons play a role in cough evoked by inhaled chemical irritants. To test this, we performed selective neurotoxin lesions of NK1 receptor expressing neurons in the paratrigeminal nucleus in guinea-pigs using substance P conjugated to saporin (SSP-SAP). Sham lesion control or SSP-SAP lesion guinea-pigs received nebulised challenges, with the pan-nociceptor stimulant bradykinin or the nodose ganglia specific stimulant adenosine 5'-triphosphate (ATP), in conscious whole-body plethysmography to study cough and associated behaviours. Laryngeal apnoea reflexes and cough evoked by mechanical stimulation of the trachea were additionally investigated in anaesthetised guinea-pigs. SSP-SAP significantly and selectively reduced the number of NK1 receptor expressing neurons in the paratrigeminal nucleus. This was associated with a significant reduction in bradykinin-evoked cough, but not ATP-evoked cough, mechanical cough or laryngeal apnoeic responses. These data provide further evidence for a role of jugular vagal pathways in cough, and additionally suggest an involvement of NK1 receptor expressing neurons in the paratrigeminal nucleus. Therefore, this neural pathway may provide novel therapeutic opportunities to treat conditions of chronic cough.
Collapse
Affiliation(s)
- Alexandria K Driessen
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Alice E McGovern
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Robert Behrens
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Aung Aung Kywe Moe
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Stuart B Mazzone
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| |
Collapse
|
20
|
Satia I, Nagashima A, Usmani OS. Exploring the role of nerves in asthma; insights from the study of cough. Biochem Pharmacol 2020; 179:113901. [PMID: 32156662 DOI: 10.1016/j.bcp.2020.113901] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 03/03/2020] [Indexed: 12/30/2022]
Abstract
Cough in asthma predicts disease severity, prognosis, and is a common and troublesome symptom. Cough is the archetypal airway neuronal reflex, yet little is understood about the underlying neuronal mechanisms. It is generally assumed that symptoms arise because of airway hyper-responsiveness and/or airway inflammation, but despite using inhaled corticosteroids and bronchodilators targeting these pathologies, a large proportion of patients have persistent coughing. This review focuses on the prevalence and impact of cough in asthma and explores data from pre-clinical and clinical studies which have explored neuronal mechanisms of cough and asthma. We present evidence to suggest patients with asthma have evidence of neuronal dysfunction, which is further heightened and exaggerated by both bronchoconstriction and airway eosinophilia. Identifying patients with excessive coughing with asthma may represent a neuro-phenotype and hence developing treatment for this symptom is important for reducing the burden of disease on patients' lives and currently represents a major unmet clinical need.
Collapse
Affiliation(s)
- I Satia
- McMaster University, Department of Medicine, Division of Respirology, Canada; Firestone Institute for Respiratory Health, St Joseph's Hospital, Canada; University of Manchester, Division of Infection, Immunity and Respiratory Medicine, and Manchester Academic Health Science Centre, Manchester, United Kingdom.
| | - A Nagashima
- McMaster University, Department of Medicine, Division of Respirology, Canada
| | | |
Collapse
|
21
|
Perry SE, Troche MS. Dual Tasking Influences Cough Sensorimotor Outcomes in Healthy Young Adults. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2019; 62:3596-3606. [PMID: 31479287 DOI: 10.1044/2019_jslhr-h-19-0122] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Purpose Reflex cough is an essential airway protective mechanism that often occurs in the context of divided attention. The effect of divided attention on measures of reflexive cough airflow and sensitivity remains unknown. We present findings from a study testing the effects of divided attention (via a dual-task paradigm) on measures of reflex cough in healthy young adults. Method Volunteers (N = 20, age = 20-40 years) underwent 4 blocks of capsaicin-induced cough challenges. Within each block, capsaicin ranging from 0 to 200 μM was presented in a randomized order. Two blocks consisted of cough testing only (single task). During the other 2 blocks, participants counted tones while simultaneously undergoing cough testing (dual task). Measures of cough motor response, self-reported urge-to-cough, cough frequency, and cough airflow were collected. Results Participants coughed more in the single-task condition compared to the dual-task condition (p ≤ .001). Participants' urge-to-cough ratings were lower in the dual-task condition (x̅ = 2, "slight") compared to the single-task condition (x̅ = 3, "moderate"; p = .007). Participants' cough reflex sensitivity thresholds were significantly increased in the dual-task condition (p = .002). Cough peak expiratory flow rates did not change between the 2 conditions (p = .34). Conclusions Somatosensation of tussive stimuli changes during dual tasking. Abnormal cortical resource allocation may be a mechanism involved in silent aspiration.
Collapse
Affiliation(s)
- Sarah E Perry
- Laboratory for the Study of Upper Airway Dysfunction, Teachers College, Columbia University, New York, NY
| | - Michelle S Troche
- Laboratory for the Study of Upper Airway Dysfunction, Teachers College, Columbia University, New York, NY
| |
Collapse
|
22
|
Ando A, Mazzone SB, Farrell MJ. Altered neural activity in brain cough suppression networks in cigarette smokers. Eur Respir J 2019; 54:13993003.00362-2019. [PMID: 31248952 DOI: 10.1183/13993003.00362-2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/12/2019] [Indexed: 11/05/2022]
Abstract
Cough is important for airway defence, and studies in healthy animals and humans have revealed multiple brain networks intimately involved in the perception of airway irritation, cough induction and cough suppression. Changes in cough sensitivity and/or the ability to suppress cough accompany pulmonary pathologies, suggesting a level of plasticity is possible in these central neural circuits. However, little is known about how persistent inputs from the lung might modify the brain processes regulating cough.In the present study, we used human functional brain imaging to investigate the central neural responses that accompany an altered cough sensitivity in cigarette smokers.In nonsmokers, inhalation of the airway irritant capsaicin induced a transient urge-to-cough associated with the activation of a distributed brain network that included sensory, prefrontal and motor cortical regions. Cigarette smokers demonstrated significantly higher thresholds for capsaicin-induced urge-to-cough, consistent with a reduced sensitivity to airway irritation. Intriguingly, this was accompanied by increased activation in brain regions known to be involved in both cough sensory processing (primary sensorimotor cortex) and cough suppression (dorsolateral prefrontal cortex and the midbrain nucleus cuneiformis). Activations in the prefrontal cortex were highest among participants with the least severe smoking behaviour, whereas those in the midbrain correlated with more severe smoking behaviour.These outcomes suggest that smoking-induced sensitisation of central cough neural circuits is offset by concurrently enhanced central suppression. Furthermore, central suppression mechanisms may evolve with the severity of smoke exposure, changing from initial prefrontal inhibition to more primitive midbrain processes as exposure increases.
Collapse
Affiliation(s)
- Ayaka Ando
- School of Biomedical Sciences, The University of Queensland, Brisbane, Australia
| | - Stuart B Mazzone
- Dept of Anatomy and Neuroscience, The University of Melbourne, Melbourne, Australia
| | - Michael J Farrell
- Dept of Medical Imaging and Radiation Sciences, Monash University, Melbourne, Australia.,Monash Biomedical Imaging Research Centre, Monash University, Melbourne, Australia
| |
Collapse
|
23
|
Farrell MJ, Mazzone SB. Are neural pathways processing airway inputs sensitized in patients with cough hypersensitivity? Pulm Pharmacol Ther 2019; 57:101806. [PMID: 31100512 DOI: 10.1016/j.pupt.2019.101806] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/13/2019] [Accepted: 05/14/2019] [Indexed: 10/26/2022]
Abstract
Patients with cough hypersensitivity exhibit unusually low thresholds for responses to tussive stimuli, exaggerated responses to suprathreshold tussive stimuli, and report spontaneous experiences of urge-to-cough in the absence of exogenous stimulation. These aberrant responses to tussive challenge have the hallmark features of behaviours associated with a sensitized sensory system. Searching for further evidence to implicate neural sensitization in the symptomatology of cough hypersensitivity warrants consideration. If up-regulation of neural circuits involved in processing of airways inputs can be demonstrated in patients with cough hypersensitivity, then strategies to reverse this dysfunctional plasticity can be contemplated and assessed. This review considers the implications of neural sensitization as a factor in the cough hypersensitivity syndrome, reflects on the limited data available in this field, and suggests prospective directions for future research.
Collapse
Affiliation(s)
- Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, School of Public and Allied Health Care, Monash University, Clayton, VIC, 3800, Australia.
| | - Stuart B Mazzone
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| |
Collapse
|
24
|
Mazzone SB. Chronic cough: a disorder of response inhibition? Eur Respir J 2019; 53:53/5/1900254. [DOI: 10.1183/13993003.00254-2019] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 02/18/2019] [Indexed: 11/05/2022]
|
25
|
Mazzone SB, Farrell MJ. Heterogeneity of cough neurobiology: Clinical implications. Pulm Pharmacol Ther 2019; 55:62-66. [DOI: 10.1016/j.pupt.2019.02.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 02/05/2019] [Accepted: 02/09/2019] [Indexed: 12/24/2022]
|
26
|
Bautista TG, Leech J, Mazzone SB, Farrell MJ. Regional brain stem activations during capsaicin inhalation using functional magnetic resonance imaging in humans. J Neurophysiol 2019; 121:1171-1182. [DOI: 10.1152/jn.00547.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Coughing is an airway protective behavior elicited by airway irritation. Animal studies show that airway sensory information is relayed via vagal sensory fibers to termination sites within dorsal caudal brain stem and thereafter relayed to more rostral sites. Using functional magnetic resonance imaging (fMRI) in humans, we previously reported that inhalation of the tussigenic stimulus capsaicin evokes a perception of airway irritation (“urge to cough”) accompanied by activations in a widely distributed brain network including the primary sensorimotor, insular, prefrontal, and posterior parietal cortices. Here we refine our imaging approach to provide a directed survey of brain stem areas activated by airway irritation. In 15 healthy participants, inhalation of capsaicin at a maximal dose that elicits a strong urge to cough without behavioral coughing was associated with activation of medullary regions overlapping with the nucleus of the solitary tract, paratrigeminal nucleus, spinal trigeminal nucleus and tract, cardiorespiratory regulatory areas homologous to the ventrolateral medulla in animals, and the midline raphe. Interestingly, the magnitude of activation within two cardiorespiratory regulatory areas was positively correlated ( r2 = 0.47, 0.48) with participants’ subjective ratings of their urge to cough. Capsaicin-related activations were also observed within the pons and midbrain. The current results add to knowledge of the representation and processing of information regarding airway irritation in the human brain, which is pertinent to the pursuit of novel cough therapies. NEW & NOTEWORTHY Functional brain imaging in humans was optimized for the brain stem. We provide the first detailed description of brain stem sites activated in response to airway irritation. The results are consistent with findings in animal studies and extend our foundational knowledge of brain processing of airway irritation in humans.
Collapse
Affiliation(s)
- Tara G. Bautista
- The Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
- Monash Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Victoria, Australia
| | - Jennifer Leech
- Monash Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Victoria, Australia
| | - Stuart B. Mazzone
- The Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, Victoria, Australia
| | - Michael J. Farrell
- Monash Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Victoria, Australia
| |
Collapse
|
27
|
Chen Z, Gu D, Fan L, Zhang W, Sun L, Chen H, Dong R, Lai K. Neuronal Activity of the Medulla Oblongata Revealed by Manganese-Enhanced Magnetic Resonance Imaging in a Rat Model of Gastroesophageal Reflux-Related Cough. Physiol Res 2018; 68:119-127. [PMID: 30433807 DOI: 10.33549/physiolres.933791] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We investigated neuronal activity of the medulla oblongata during gastroesophageal reflux-related cough (GERC). A rat model of GERC was generated by perfusing HCl into lower esophagus and inducing cough with citric acid. The HCl group rat was received HCl perfusion without citric acid-induced cough. The saline control rat was perfused with saline instead and cough was induced. Citric acid-induced cough rat was only induced by citric acid. Blank group rats were fed normally. Fos expressions were observed in medulla oblongata nuclei using immunohistochemistry. Manganese-enhanced magnetic resonance imaging (MEMRI) was performed to detect the Mn(2+) signal following intraperitoneal injection of MnCl(2). HCl perfusion and citric acid-induced cough caused Fos expressions in the nucleus of solitary tract (nTS), dorsal motor nucleus of the vagus (DMV), paratrigeminal nucleus (Pa5), and intermediate reticular nucleus (IRt), which was higher than HCl group, saline control group, citric acid-induced cough group, and blank group. A high Mn(2+) signal was also observed in most of these nuclei in model rats, compared with blank group animals. The Mn(2+) signal was also higher in the HCl, saline and citric acid-induced cough group animals, compared with blank group animals. The study showed medulla oblongata neurons were excited in a HCl perfusion and citric acid-induced cough rat model, and nTS, DMV, Pa5 and IRt neurons maybe involved in the cough process and signal integrate.
Collapse
Affiliation(s)
- Zhe Chen
- The First People's Hospital of Kunshan, Jiangsu University, Suzhou, China
| | - Dachuan Gu
- Fu Wai Hospital, Peking Union Medical College, Beijing, China
| | - Linfeng Fan
- The Second Affiliated Hospital of Zhejiang University School of Medicine, Zhejiang University, Hangzhou, China
| | - Weitao Zhang
- Zhongshan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Lejia Sun
- Peking Union Medical College, Beijing, China
| | - Hui Chen
- First Affiliated Hospital of Soochow University, Suzhou, China
| | - Rong Dong
- Medical School of Southeast University, Nanjing, China
| | - Kefang Lai
- State Key Laboratory of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Institute of Respiratory Disease, Guangzhou, China
| |
Collapse
|
28
|
Mazzone SB, Chung KF, McGarvey L. The heterogeneity of chronic cough: a case for endotypes of cough hypersensitivity. THE LANCET RESPIRATORY MEDICINE 2018; 6:636-646. [DOI: 10.1016/s2213-2600(18)30150-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/31/2018] [Accepted: 04/04/2018] [Indexed: 12/15/2022]
|
29
|
Driessen AK, McGovern AE, Narula M, Yang SK, Keller JA, Farrell MJ, Mazzone SB. Central mechanisms of airway sensation and cough hypersensitivity. Pulm Pharmacol Ther 2017; 47:9-15. [DOI: 10.1016/j.pupt.2017.01.010] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 01/25/2017] [Indexed: 12/11/2022]
|
30
|
Sex differences in cough reflex. Respir Physiol Neurobiol 2017; 245:122-129. [DOI: 10.1016/j.resp.2016.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 12/07/2016] [Accepted: 12/08/2016] [Indexed: 12/31/2022]
|
31
|
McGovern AE, Ajayi IE, Farrell MJ, Mazzone SB. A neuroanatomical framework for the central modulation of respiratory sensory processing and cough by the periaqueductal grey. J Thorac Dis 2017; 9:4098-4107. [PMID: 29268420 DOI: 10.21037/jtd.2017.08.119] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Sensory information arising from the airways is processed in a distributed brain network that encodes for the discriminative and affective components of the resultant sensations. These higher brain networks in turn regulate descending motor control circuits that can both promote or suppress behavioural responses. Here we explore the existence of possible descending neural control pathways that regulate airway afferent processing in the brainstem, analogous to the endogenous descending analgesia system described for noxious somatosensation processing and placebo analgesia. A key component of this circuitry is the midbrain periaqueductal grey, a region of the brainstem recently highlighted for its altered activity in patients with chronic cough. Understanding the nature and plasticity of descending neural control may help identify novel central therapeutic targets to alleviate the neuronal hypersensitivity underpinning many symptoms of respiratory disease.
Collapse
Affiliation(s)
- Alice E McGovern
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville VIC 3010, Australia
| | - Itopa E Ajayi
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville VIC 3010, Australia
| | - Michael J Farrell
- Monash Biomedicine Discovery Institute and Department of Medical Imaging and Radiation Sciences, Monash University, Clayton VIC 3800, Australia
| | - Stuart B Mazzone
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville VIC 3010, Australia
| |
Collapse
|
32
|
Mazzone SB, Undem BJ. Vagal Afferent Innervation of the Airways in Health and Disease. Physiol Rev 2017; 96:975-1024. [PMID: 27279650 DOI: 10.1152/physrev.00039.2015] [Citation(s) in RCA: 326] [Impact Index Per Article: 46.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Vagal sensory neurons constitute the major afferent supply to the airways and lungs. Subsets of afferents are defined by their embryological origin, molecular profile, neurochemistry, functionality, and anatomical organization, and collectively these nerves are essential for the regulation of respiratory physiology and pulmonary defense through local responses and centrally mediated neural pathways. Mechanical and chemical activation of airway afferents depends on a myriad of ionic and receptor-mediated signaling, much of which has yet to be fully explored. Alterations in the sensitivity and neurochemical phenotype of vagal afferent nerves and/or the neural pathways that they innervate occur in a wide variety of pulmonary diseases, and as such, understanding the mechanisms of vagal sensory function and dysfunction may reveal novel therapeutic targets. In this comprehensive review we discuss historical and state-of-the-art concepts in airway sensory neurobiology and explore mechanisms underlying how vagal sensory pathways become dysfunctional in pathological conditions.
Collapse
Affiliation(s)
- Stuart B Mazzone
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, Australia; and Department of Medicine, Johns Hopkins University Medical School, Asthma & Allergy Center, Baltimore, Maryland
| | - Bradley J Undem
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, Australia; and Department of Medicine, Johns Hopkins University Medical School, Asthma & Allergy Center, Baltimore, Maryland
| |
Collapse
|
33
|
Brandimore AE, Hegland KW, Okun MS, Davenport PW, Troche MS. Voluntary upregulation of reflex cough is possible in healthy older adults and Parkinson's disease. J Appl Physiol (1985) 2017; 123:19-26. [PMID: 28360120 DOI: 10.1152/japplphysiol.00612.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 02/24/2017] [Accepted: 03/22/2017] [Indexed: 11/22/2022] Open
Abstract
Cough is an airway-protective mechanism that serves to detect and forcefully eject aspirate material. Existing research has identified the ability of healthy young adults to suppress or modify cough motor output based on external cueing. However, no study has evaluated the ability of people with Parkinson's disease (PD) and healthy older adults (HOAs) to upregulate cough motor output. The goal of this study was to evaluate the ability of people with PD and healthy age-matched controls (HOAs) to upregulate reflex and voluntary cough function volitionally with verbal instruction and visual biofeedback of airflow targets. Sixteen participants with PD and twenty-eight HOAs (56-83 yr old) were recruited for this study. Experimental procedures used spirometry to evaluate 1) baseline reflex cough (evoked with capsaicin) and voluntary sequential cough and 2) reflex and voluntary cough with upregulation biofeedback. Cough airflow was recorded and repeated-measures ANOVA was used to analyze differences in cough airflow parameters. Cough peak expiratory airflow rate and cough expired volume were significantly greater in the cueing condition for both induced reflex (P < 0.001) and voluntary cough (P < 0.001) compared with baseline measures. This is the first study to demonstrate the ability of people with PD and HOAs to upregulate induced reflex and voluntary cough motor output volitionally. These results support the development of studies targeting improved cough effectiveness in patients with airway-protective deficits.NEW & NOTEWORTHY Aspiration pneumonia is a leading cause of death in Parkinson's disease (PD) and results from concurrent dysphagia and dystussia (cough dysfunction). This is the first study to demonstrate that people with PD and healthy age-matched controls can volitionally upregulate induced reflex and voluntary cough effectiveness when presented with novel cueing strategies. Thus targeting upregulation of cough effectiveness via biofeedback may be a viable way to enhance airway protection in people with PD.
Collapse
Affiliation(s)
- Alexandra E Brandimore
- Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, New York.,Center for Movement Disorders and Neurorestoration, University of Florida, Gainesville, Florida.,Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, Florida
| | - Karen W Hegland
- Center for Movement Disorders and Neurorestoration, University of Florida, Gainesville, Florida.,Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, Florida.,Department of Neurology, University of Florida, Gainesville, Florida; and
| | - Michael S Okun
- Center for Movement Disorders and Neurorestoration, University of Florida, Gainesville, Florida.,Department of Neurology, University of Florida, Gainesville, Florida; and
| | - Paul W Davenport
- Department of Physiological Sciences, University of Florida, Gainesville, Florida
| | - Michelle S Troche
- Department of Biobehavioral Sciences, Teachers College, Columbia University, New York, New York; .,Center for Movement Disorders and Neurorestoration, University of Florida, Gainesville, Florida
| |
Collapse
|
34
|
Tsai HW, Fennelly K, Wheeler-Hegland K, Adams S, Condrey J, Hosford JL, Davenport PW. Cough physiology in elderly women with nontuberculous mycobacterial lung infections. J Appl Physiol (1985) 2017; 122:1262-1266. [PMID: 28255087 DOI: 10.1152/japplphysiol.00939.2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 11/22/2022] Open
Abstract
Elderly white, thin, nonsmoking women appear to be more susceptible to lung infections with Mycobacterium avium complex and other nontuberculous mycobacteria (NTM). It has been postulated that such disease in women is related to suppression of their cough. We hypothesized that patients with pulmonary NTM (pNTM) infections may have altered cough physiology compared with unaffected control subjects. We used capsaicin-induced cough to assess the cough reflex in pNTM subjects. Eight elderly white women with stable chronic pNTM infections and six unaffected age-matched control subjects were recruited. There was no significant difference between groups in capsaicin-elicited cough motor response, airflow pattern, or cough frequency. The urge-to-cough (UTC) score at the lowest capsaicin concentration was significantly lower in pNTM than control subjects (P < 0.05). There were no significant differences in the UTC score between pNTM and control subjects at >50 μM capsaicin. These results suggest lower UTC sensitivity to the lowest concentration of capsaicin in pNTM than control subjects. In other words, the pNTM subjects do not sense a UTC when the stimulus is relatively small.NEW & NOTEWORTHY This study investigates the cough motor response and cough sensitivity in patients with nontuberculous mycobacteria (NTM) infection. In elderly white female pulmonary NTM subjects, we demonstrated a capacity to produce coughs similar to that of age-matched control subjects but decreased cough sensitivity in response to a low dose of capsaicin compared with control subjects. These findings are important to understand the pathophysiological mechanisms resulting in NTM disease in elderly white women and/or the syndrome developing in elderly white female NTM patients.
Collapse
Affiliation(s)
- Hsiu-Wen Tsai
- Department of Physiological Sciences, University of Florida, Gainesville, Florida
| | - Kevin Fennelly
- Department of Medicine, University of Florida, Gainesville, Florida; and
| | - Karen Wheeler-Hegland
- Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, Florida
| | - Sherry Adams
- Department of Physiological Sciences, University of Florida, Gainesville, Florida
| | - Jillian Condrey
- Department of Physiological Sciences, University of Florida, Gainesville, Florida
| | - Jennifer L Hosford
- Department of Medicine, University of Florida, Gainesville, Florida; and
| | - Paul W Davenport
- Department of Physiological Sciences, University of Florida, Gainesville, Florida;
| |
Collapse
|
35
|
Audrit KJ, Delventhal L, Aydin Ö, Nassenstein C. The nervous system of airways and its remodeling in inflammatory lung diseases. Cell Tissue Res 2017; 367:571-590. [PMID: 28091773 DOI: 10.1007/s00441-016-2559-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 12/13/2016] [Indexed: 12/20/2022]
Abstract
Inflammatory lung diseases are associated with bronchospasm, cough, dyspnea and airway hyperreactivity. The majority of these symptoms cannot be primarily explained by immune cell infiltration. Evidence has been provided that vagal efferent and afferent neurons play a pivotal role in this regard. Their functions can be altered by inflammatory mediators that induce long-lasting changes in vagal nerve activity and gene expression in both peripheral and central neurons, providing new targets for treatment of pulmonary inflammatory diseases.
Collapse
Affiliation(s)
- Katrin Julia Audrit
- Institute of Anatomy and Cell Biology, Aulweg 123, 35385, Giessen, Germany.,German Center for Lung Research (DZL), Giessen, Germany
| | - Lucas Delventhal
- Institute of Anatomy and Cell Biology, Aulweg 123, 35385, Giessen, Germany.,German Center for Lung Research (DZL), Giessen, Germany
| | - Öznur Aydin
- Institute of Anatomy and Cell Biology, Aulweg 123, 35385, Giessen, Germany.,German Center for Lung Research (DZL), Giessen, Germany
| | - Christina Nassenstein
- Institute of Anatomy and Cell Biology, Aulweg 123, 35385, Giessen, Germany. .,German Center for Lung Research (DZL), Giessen, Germany.
| |
Collapse
|
36
|
Ando A, Smallwood D, McMahon M, Irving L, Mazzone SB, Farrell MJ. Neural correlates of cough hypersensitivity in humans: evidence for central sensitisation and dysfunctional inhibitory control. Thorax 2016; 71:323-9. [DOI: 10.1136/thoraxjnl-2015-207425] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Accepted: 01/07/2016] [Indexed: 12/17/2022]
|
37
|
Brandimore AE, Troche MS, Huber JE, Hegland KW. Respiratory kinematic and airflow differences between reflex and voluntary cough in healthy young adults. Front Physiol 2015; 6:284. [PMID: 26500560 PMCID: PMC4598583 DOI: 10.3389/fphys.2015.00284] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 09/24/2015] [Indexed: 02/06/2023] Open
Abstract
Background: Cough is a defensive behavior that can be initiated in response to a stimulus in the airway (reflexively), or on command (voluntarily). There is evidence to suggest that physiological differences exist between reflex and voluntary cough; however, the output (mechanistic and airflow) differences between the cough types are not fully understood. Therefore, the aims of this study were to determine the lung volume, respiratory kinematic, and airflow differences between reflex and voluntary cough in healthy young adults. Methods: Twenty-five participants (14 female; 18–29 years) were recruited for this study. Participants were evaluated using respiratory inductance plethysmography calibrated with spirometry. Experimental procedures included: (1) respiratory calibration, (2) three voluntary sequential cough trials, and (3) three reflex cough trials induced with 200 μM capsaicin. Results: Lung volume initiation (LVI; p = 0.003) and lung volume excursion (LVE; p < 0.001) were significantly greater for voluntary cough compared to reflex cough. The rib cage and abdomen significantly influenced LVI for voluntary cough (p < 0.001); however, only the rib cage significantly impacted LVI for reflex cough (p < 0.001). LVI significantly influenced peak expiratory flow rate (PEFR) for voluntary cough (p = 0.029), but not reflex cough (p = 0.610). Discussion: Production of a reflex cough results in significant mechanistic and airflow differences compared to voluntary cough. These findings suggest that detection of a tussigenic stimulus modifies motor aspects of the reflex cough behavior. Further understanding of the differences between reflex and voluntary cough in older adults and in persons with dystussia (cough dysfunction) will be essential to facilitate the development of successful cough treatment paradigms.
Collapse
Affiliation(s)
- Alexandra E Brandimore
- Department of Speech, Language, and Hearing Sciences, University of Florida Gainesville, FL, USA ; Malcom Randall VA Medical Center, Brain Rehabilitation Research Center Gainesville, FL, USA
| | - Michelle S Troche
- Department of Biobehavioral Sciences, Teachers College Columbia University New York, NY, USA
| | - Jessica E Huber
- Department of Speech, Language, and Hearing Sciences, Purdue University West Lafayette, IN, USA
| | - Karen W Hegland
- Department of Speech, Language, and Hearing Sciences, University of Florida Gainesville, FL, USA
| |
Collapse
|
38
|
Multiple neural circuits mediating airway sensations: Recent advances in the neurobiology of the urge-to-cough. Respir Physiol Neurobiol 2015; 226:115-20. [PMID: 26455780 DOI: 10.1016/j.resp.2015.09.017] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 09/30/2015] [Accepted: 09/30/2015] [Indexed: 12/31/2022]
Abstract
The respiratory system is densely innervated by sensory neurons arising from the jugular (superior) and nodose (inferior) vagal ganglia. However, a distinction exists between jugular and nodose neurons as these ganglia developmentally originate from the neural crest and the epibranchial placodes, respectively. This different embryological origin underpins an important source of heterogeneity in vagal afferent biology, and may extend to include fundamentally different central neural circuits that are in receipt of jugular versus nodose afferent inputs. Indeed, recent studies using viral tract tracing and human brain imaging support the notion that airway sensors contribute inputs to multiple central circuits. Understanding the neural pathways arising from the airways and lungs may provide novel insights into aberrant sensations, such as the urge-to-cough, characteristic of respiratory disease.
Collapse
|
39
|
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.
Collapse
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
| |
Collapse
|
40
|
Farrell MJ, Trevaks D, Taylor NAS, McAllen RM. Regional brain responses associated with thermogenic and psychogenic sweating events in humans. J Neurophysiol 2015; 114:2578-87. [PMID: 26289468 DOI: 10.1152/jn.00601.2015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 08/18/2015] [Indexed: 12/30/2022] Open
Abstract
Sweating events occur in response to mental stress (psychogenic) or with increased body temperature (thermogenic). We previously found that both were linked to activation of common brain stem regions, suggesting that they share the same output pathways: a putative common premotor nucleus was identified in the rostral-lateral medulla (Farrell MJ, Trevaks D, Taylor NA, McAllen RM. Am J Physiol Regul Integr Comp Physiol 304: R810-R817, 2013). We therefore looked in higher brain regions for the neural basis that differentiates the two types of sweating event. Previous work has identified hemispheric activations linked to psychogenic sweating, but no corresponding data have been reported for thermogenic sweating. Galvanic skin responses were used to measure sweating events in two groups of subjects during either psychogenic sweating (n = 11, 35.3 ± 11.8 yr) or thermogenic sweating (n = 11, 34.4 ± 10.2 yr) while regional brain activation was measured by BOLD signals in a 3-Tesla MRI scanner. Common regions activated with sweating events in both groups included the anterior and posterior cingulate cortex, insula, premotor cortex, thalamus, lentiform nuclei, and cerebellum (P(corrected) < 0.05). Psychogenic sweating events were associated with significantly greater activation in the dorsal midcingulate cortex, parietal cortex, premotor cortex, occipital cortex, and cerebellum. No hemispheric region was found to show statistically significantly greater activation with thermogenic than with psychogenic sweating events. However, a discrete cluster of activation in the anterior hypothalamus/preoptic area was seen only with thermogenic sweating events. These findings suggest that the expected association between sweating events and brain regions implicated in "arousal" may apply selectively to psychogenic sweating; the neural basis for thermogenic sweating events may be subcortical.
Collapse
Affiliation(s)
- Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, Monash University, Clayton, Australia; Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia;
| | - David Trevaks
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia
| | - Nigel A S Taylor
- Centre for Human and Applied Physiology, School of Medicine, University of Wollongong, Wollongong, Australia; and
| | - Robin M McAllen
- Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia; Anatomy and Neuroscience, University of Melbourne, Melbourne, Australia
| |
Collapse
|
41
|
Distinct brainstem and forebrain circuits receiving tracheal sensory neuron inputs revealed using a novel conditional anterograde transsynaptic viral tracing system. J Neurosci 2015; 35:7041-55. [PMID: 25948256 DOI: 10.1523/jneurosci.5128-14.2015] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Sensory nerves innervating the mucosa of the airways monitor the local environment for the presence of irritant stimuli and, when activated, provide input to the nucleus of the solitary tract (Sol) and paratrigeminal nucleus (Pa5) in the medulla to drive a variety of protective behaviors. Accompanying these behaviors are perceivable sensations that, particularly for stimuli in the proximal end of the airways, can be discrete and localizable. Airway sensations likely reflect the ascending airway sensory circuitry relayed via the Sol and Pa5, which terminates broadly throughout the CNS. However, the relative contribution of the Sol and Pa5 to these ascending pathways is not known. In the present study, we developed and characterized a novel conditional anterograde transneuronal viral tracing system based on the H129 strain of herpes simplex virus 1 and used this system in rats along with conventional neuroanatomical tracing with cholera toxin B to identify subcircuits in the brainstem and forebrain that are in receipt of relayed airway sensory inputs via the Sol and Pa5. We show that both the Pa5 and proximal airways disproportionately receive afferent terminals arising from the jugular (rather than nodose) vagal ganglia and the output of the Pa5 is predominately directed toward the ventrobasal thalamus. We propose the existence of a somatosensory-like pathway from the proximal airways involving jugular ganglia afferents, the Pa5, and the somatosensory thalamus and suggest that this pathway forms the anatomical framework for sensations arising from the proximal airway mucosa.
Collapse
|
42
|
Subirà M, Sato JR, Alonso P, do Rosário MC, Segalàs C, Batistuzzo MC, Real E, Lopes AC, Cerrillo E, Diniz JB, Pujol J, Assis RO, Menchón JM, Shavitt RG, Busatto GF, Cardoner N, Miguel EC, Hoexter MQ, Soriano-Mas C. Brain structural correlates of sensory phenomena in patients with obsessive-compulsive disorder. J Psychiatry Neurosci 2015; 40:232-40. [PMID: 25652753 PMCID: PMC4478056 DOI: 10.1503/jpn.140118] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Sensory phenomena (SP) are uncomfortable feelings, including bodily sensations, sense of inner tension, "just-right" perceptions, feelings of incompleteness, or "urge-only" phenomena, which have been described to precede, trigger or accompany repetitive behaviours in individuals with obsessive-compulsive disorder (OCD). Sensory phenomena are also observed in individuals with tic disorders, and previous research suggests that sensorimotor cortex abnormalities underpin the presence of SP in such patients. However, to our knowledge, no studies have assessed the neural correlates of SP in patients with OCD. METHODS We assessed the presence of SP using the University of São Paulo Sensory Phenomena Scale in patients with OCD and healthy controls from specialized units in São Paulo, Brazil, and Barcelona, Spain. All participants underwent a structural magnetic resonance examination, and brain images were examined using DARTEL voxel-based morphometry. We evaluated grey matter volume differences between patients with and without SP and healthy controls within the sensorimotor and premotor cortices. RESULTS We included 106 patients with OCD and 87 controls in our study. Patients with SP (67% of the sample) showed grey matter volume increases in the left sensorimotor cortex in comparison to patients without SP and bilateral sensorimotor cortex grey matter volume increases in comparison to controls. No differences were observed between patients without SP and controls. LIMITATIONS Most patients were medicated. Participant recruitment and image acquisition were performed in 2 different centres. CONCLUSION We have identified a structural correlate of SP in patients with OCD involving grey matter volume increases within the sensorimotor cortex; this finding is in agreement with those of tic disorder studies showing that abnormal activity and volume increases within this region are associated with the urges preceding tic onset.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Marcelo Q. Hoexter
- Correspondence to: M. Hoexter, Department & Institute of Psychiatry, University of São Paulo Medical School, Rua Ovídio Pires de Campos, 785-3°andar Ala Norte-sala 9, São Paulo, Brazil, , or C. Soriano-Mas, Bellvitge Biomedical Research Institute-IDIBELL, Psychiatry Department, Bellvitge University Hospital, Feixa Llarga s/n 08907, Hospitalet de Llobregat, Barcelona, Spain;
| | - Carles Soriano-Mas
- Correspondence to: M. Hoexter, Department & Institute of Psychiatry, University of São Paulo Medical School, Rua Ovídio Pires de Campos, 785-3°andar Ala Norte-sala 9, São Paulo, Brazil, , or C. Soriano-Mas, Bellvitge Biomedical Research Institute-IDIBELL, Psychiatry Department, Bellvitge University Hospital, Feixa Llarga s/n 08907, Hospitalet de Llobregat, Barcelona, Spain;
| |
Collapse
|
43
|
Undem BJ, Zaccone E, McGarvey L, Mazzone SB. Neural dysfunction following respiratory viral infection as a cause of chronic cough hypersensitivity. Pulm Pharmacol Ther 2015; 33:52-6. [PMID: 26141017 DOI: 10.1016/j.pupt.2015.06.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/16/2015] [Accepted: 06/26/2015] [Indexed: 02/03/2023]
Abstract
Respiratory viral infections are a common cause of acute coughing, an irritating symptom for the patient and an important mechanism of transmission for the virus. Although poorly described, the inflammatory consequences of infection likely induce coughing by chemical (inflammatory mediator) or mechanical (mucous) activation of the cough-evoking sensory nerves that innervate the airway wall. For some individuals, acute cough can evolve into a chronic condition, in which cough and aberrant airway sensations long outlast the initial viral infection. This suggests that some viruses have the capacity to induce persistent plasticity in the neural pathways mediating cough. In this brief review we present the clinical evidence of acute and chronic neural dysfunction following viral respiratory tract infections and explore possible mechanisms by which the nervous system may undergo activation, sensitization and plasticity.
Collapse
Affiliation(s)
- Bradley J Undem
- Department of Medicine, Johns Hopkins Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Baltimore, MD, 21224, USA.
| | - Eric Zaccone
- Department of Medicine, Johns Hopkins Asthma and Allergy Center, 5501 Hopkins Bayview Circle, Baltimore, MD, 21224, USA
| | - Lorcan McGarvey
- Centre of Infection and Immunity, The Queen's University of Belfast, Belfast, Northern Ireland, BT12 6BJ, UK.
| | - Stuart B Mazzone
- School of Biomedical Sciences, The University of Queensland, St Lucia, Brisbane, QLD, 4072, Australia.
| |
Collapse
|
44
|
Zhang S, Tsai SJ, Hu S, Xu J, Chao HH, Calhoun VD, Li CSR. Independent component analysis of functional networks for response inhibition: Inter-subject variation in stop signal reaction time. Hum Brain Mapp 2015; 36:3289-302. [PMID: 26089095 DOI: 10.1002/hbm.22819] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Revised: 03/06/2015] [Accepted: 04/06/2015] [Indexed: 01/11/2023] Open
Abstract
Cognitive control is a critical executive function. Many studies have combined general linear modeling and the stop signal task (SST) to delineate the component processes of cognitive control. For instance, by contrasting stop success (SS) and stop error (SE) trials in the SST, investigators examined regional responses to stop signal inhibition. In contrast to this parameterized approach, independent component analysis (ICA) elucidates brain networks subserving cognitive control. In our earlier work of 59 adults performing the SST during fMRI, we characterized six independent components (ICs). However, none of these ICs correlated with stop signal performance, raising questions about their behavioral validity. Here, in a larger sample (n = 100), we identified and explored 23 ICs for correlation with the stop signal reaction time (SSRT), a measure of the efficiency of response inhibition. At a corrected threshold (P < 0.0005), a paracentral lobule-midcingulate network and a left inferior parietal-supplementary motor-somatomotor network showed a positive correlation between SE beta weight and SSRT. In contrast, a midline cerebellum-thalamus-pallidum network showed a negative correlation between SE beta weight and SSRT. These findings suggest that motor preparation and execution prolongs the SSRT, likely via an interaction between the go and stop processes as suggested by the race model. Behaviorally, consistent with this hypothesis, the difference in G and SE reaction times is positively correlated with SSRT across subjects. These new results highlight the importance of cognitive motor regions in response inhibition and support the utility of ICA in uncovering functional networks for cognitive control in the SST.
Collapse
Affiliation(s)
- Sheng Zhang
- Department of Psychiatry, Yale University, New Haven, Connecticut
| | - Shang-Jui Tsai
- Department of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Sien Hu
- Department of Psychiatry, Yale University, New Haven, Connecticut
| | - Jiansong Xu
- Department of Psychiatry, Yale University, New Haven, Connecticut
| | - Herta H Chao
- Department of Internal Medicine, Yale University, New Haven, Connecticut.,Medical Service, VA Connecticut Health Care System, West Haven, Connecticut
| | - Vince D Calhoun
- Department of Psychiatry, Yale University, New Haven, Connecticut.,The Mind Research Network, Albuquerque, New Mexico.,Department of Electrical and Computer Engineering, The University of New Mexico, Albuquerque, New Mexico
| | - Chiang-Shan R Li
- Department of Psychiatry, Yale University, New Haven, Connecticut.,Department of Neurobiology, Yale University, New Haven, Connecticut.,Interdepartmental Neuroscience Program, Yale University, New Haven, Connecticut
| |
Collapse
|
45
|
Canning BJ, Chang AB, Bolser DC, Smith JA, Mazzone SB, McGarvey L. Anatomy and neurophysiology of cough: CHEST Guideline and Expert Panel report. Chest 2015; 146:1633-1648. [PMID: 25188530 PMCID: PMC4251621 DOI: 10.1378/chest.14-1481] [Citation(s) in RCA: 168] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Bronchopulmonary C-fibers and a subset of mechanically sensitive, acid-sensitive myelinated sensory nerves play essential roles in regulating cough. These vagal sensory nerves terminate primarily in the larynx, trachea, carina, and large intrapulmonary bronchi. Other bronchopulmonary sensory nerves, sensory nerves innervating other viscera, as well as somatosensory nerves innervating the chest wall, diaphragm, and abdominal musculature regulate cough patterning and cough sensitivity. The responsiveness and morphology of the airway vagal sensory nerve subtypes and the extrapulmonary sensory nerves that regulate coughing are described. The brainstem and higher brain control systems that process this sensory information are complex, but our current understanding of them is considerable and increasing. The relevance of these neural systems to clinical phenomena, such as urge to cough and psychologic methods for treatment of dystussia, is high, and modern imaging methods have revealed potential neural substrates for some features of cough in the human.
Collapse
Affiliation(s)
| | - Anne B Chang
- Queensland Children's Respiratory Centre, Royal Children's Hospital, Brisbane, QLD, Australia, Child Health Division, Menzies School of Health, Darwin, NT, Australia
| | - Donald C Bolser
- Department of Physiological Sciences, University of Florida, Gainesville, FL
| | - Jaclyn A Smith
- Centre for Respiratory and Allergy, University of Manchester, Manchester, England
| | - Stuart B Mazzone
- School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Lorcan McGarvey
- Centre for Infection and Immunity, The Queen's University of Belfast, Belfast, Northern Ireland.
| | | |
Collapse
|
46
|
Mazzone SB, McGovern AE, Farrell MJ. Endogenous central suppressive mechanisms regulating cough as potential targets for novel antitussive therapies. Curr Opin Pharmacol 2015; 22:1-8. [PMID: 25704497 DOI: 10.1016/j.coph.2015.02.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Revised: 02/04/2015] [Accepted: 02/04/2015] [Indexed: 02/05/2023]
Abstract
Cough and the accompanying sensation known as the urge-to-cough are complex neurobiological phenomena dependent on sensory and motor neural processing at many levels of the neuraxis. In addition to the excitatory neural circuits that provide the positive drive for inducing cough and the urge-to-cough, recent studies have highlighted the existence of likely inhibitory central neural processes that can be engaged to suppress cough sensorimotor processing. In many respects, the balance between excitatory and inhibitory central cough control may be a critical determinant of cough in health and disease which argues for the importance of understanding the biology of these putative central inhibitory processes. This brief review summarises the current knowledge of the central circuits that govern voluntary and involuntary cough suppression and posits the notion of targeting central suppressive mechanisms as a treatment for disordered cough in disease.
Collapse
Affiliation(s)
- Stuart B Mazzone
- School of Biomedical Sciences, The University of Queensland, Australia.
| | - Alice E McGovern
- School of Biomedical Sciences, The University of Queensland, Australia
| | - Michael J Farrell
- Department of Medical Imaging and Radiation Sciences, Monash University, Australia
| |
Collapse
|
47
|
Peripheral neural circuitry in cough. Curr Opin Pharmacol 2015; 22:9-17. [PMID: 25704498 DOI: 10.1016/j.coph.2015.02.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 02/02/2015] [Accepted: 02/04/2015] [Indexed: 01/22/2023]
Abstract
Cough is a reflex that serves to protect the airways. Excessive or chronic coughing is a major health issue that is poorly controlled by current therapeutics. Significant effort has been made to understand the mechanisms underlying the cough reflex. The focus of this review is the evidence supporting the role of specific airway sensory nerve (afferent) populations in the initiation and modulation of the cough reflex in health and disease.
Collapse
|
48
|
Troche MS, Brandimore AE, Godoy J, Hegland KW. A framework for understanding shared substrates of airway protection. J Appl Oral Sci 2014; 22:251-60. [PMID: 25141195 PMCID: PMC4126819 DOI: 10.1590/1678-775720140132] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2014] [Accepted: 05/06/2014] [Indexed: 02/01/2023] Open
Abstract
Deficits of airway protection can have deleterious effects to health and quality of
life. Effective airway protection requires a continuum of behaviors including
swallowing and cough. Swallowing prevents material from entering the airway and
coughing ejects endogenous material from the airway. There is significant overlap
between the control mechanisms for swallowing and cough. In this review we will
present the existing literature to support a novel framework for understanding shared
substrates of airway protection. This framework was originally adapted from Eccles'
model of cough28 (2009) by Hegland,
et al.42 (2012). It will serve to
provide a basis from which to develop future studies and test specific hypotheses
that advance our field and ultimately improve outcomes for people with airway
protective deficits.
Collapse
Affiliation(s)
- Michelle Shevon Troche
- Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, FL, USA
| | | | - Juliana Godoy
- Bauru School of Dentistry, University of São Paulo, Bauru, SP, Brazil
| | - Karen Wheeler Hegland
- Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, FL, USA
| |
Collapse
|
49
|
Farrell M, Mazzone S. Sensations and regional brain responses evoked by tussive stimulation of the airways. Respir Physiol Neurobiol 2014; 204:58-63. [DOI: 10.1016/j.resp.2014.06.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Accepted: 06/13/2014] [Indexed: 02/04/2023]
|
50
|
Narula M, McGovern AE, Yang SK, Farrell MJ, Mazzone SB. Afferent neural pathways mediating cough in animals and humans. J Thorac Dis 2014; 6:S712-9. [PMID: 25383205 DOI: 10.3978/j.issn.2072-1439.2014.03.15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 03/04/2014] [Indexed: 12/12/2022]
Abstract
The airways and lungs are densely innervated by sensory nerves, which subserve multiple roles in both the normal physiological control of respiratory functions and in pulmonary defense. These sensory nerves are therefore not homogeneous in nature, but rather have physiological, molecular and anatomical phenotypes that reflect their purpose. All sensory neuron subtypes provide input to the central nervous system and drive reflex changes in respiratory and airway functions. But less appreciated is that ascending projections from these brainstem inputs to higher brain regions can also induce behavioural changes in respiration. In this brief review we provide an overview of the current understanding of airway sensory pathways, with specific reference to those involved in reflex and behavioural cough responses following airways irritation.
Collapse
Affiliation(s)
- Monica Narula
- 1 School of Biomedical Sciences, University of Queensland, QLD 4072, Australia ; 2 The Florey Institute of Neuroscience and Mental Health, VIC 3010, Australia
| | - Alice E McGovern
- 1 School of Biomedical Sciences, University of Queensland, QLD 4072, Australia ; 2 The Florey Institute of Neuroscience and Mental Health, VIC 3010, Australia
| | - Seung-Kwon Yang
- 1 School of Biomedical Sciences, University of Queensland, QLD 4072, Australia ; 2 The Florey Institute of Neuroscience and Mental Health, VIC 3010, Australia
| | - Michael J Farrell
- 1 School of Biomedical Sciences, University of Queensland, QLD 4072, Australia ; 2 The Florey Institute of Neuroscience and Mental Health, VIC 3010, Australia
| | - Stuart B Mazzone
- 1 School of Biomedical Sciences, University of Queensland, QLD 4072, Australia ; 2 The Florey Institute of Neuroscience and Mental Health, VIC 3010, Australia
| |
Collapse
|