1
|
Alewel DI, Jackson TW, Vance SA, Schladweiler MC, Evansky PA, Henriquez AR, Grindstaff R, Gavett SH, Kodavanti UP. Sex-specific respiratory and systemic endocrine effects of acute acrolein and trichloroethylene inhalation. Toxicol Lett 2023; 382:22-32. [PMID: 37201588 PMCID: PMC10585336 DOI: 10.1016/j.toxlet.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2023] [Revised: 04/23/2023] [Accepted: 05/11/2023] [Indexed: 05/20/2023]
Abstract
Acrolein and trichloroethylene (TCE) are priority hazardous air pollutants due to environmental prevalence and adverse health effects; however, neuroendocrine stress-related systemic effects are not characterized. Comparing acrolein, an airway irritant, and TCE with low irritancy, we hypothesized that airway injury would be linked to neuroendocrine-mediated systemic alterations. Male and female Wistar-Kyoto rats were exposed nose-only to air, acrolein or TCE in incremental concentrations over 30 min, followed by 3.5-hr exposure to the highest concentration (acrolein - 0.0, 0.1, 0.316, 1, 3.16 ppm; TCE - 0.0, 3.16, 10, 31.6, 100 ppm). Real-time head-out plethysmography revealed acrolein decreased minute volume and increased inspiratory-time (males>females), while TCE reduced tidal-volume. Acrolein, but not TCE, inhalation increased nasal-lavage-fluid protein, lactate-dehydrogenase activity, and inflammatory cell influx (males>females). Neither acrolein nor TCE increased bronchoalveolar-lavage-fluid injury markers, although macrophages and neutrophils increased in acrolein-exposed males and females. Systemic neuroendocrine stress response assessment indicated acrolein, but not TCE, increased circulating adrenocorticotrophic hormone, and consequently corticosterone, and caused lymphopenia, but only in males. Acrolein also reduced circulating thyroid-stimulating hormone, prolactin, and testosterone in males. In conclusion, acute acrolein inhalation resulted in sex-specific upper respiratory irritation/inflammation and systemic neuroendocrine alterations linked to hypothalamic-pituitary-adrenal axes activation, which is critical in mediating extra-respiratory effects.
Collapse
Affiliation(s)
- Devin I Alewel
- Oak Ridge Institute for Science and Education Research Participation Program, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Thomas W Jackson
- Oak Ridge Institute for Science and Education Research Participation Program, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Samuel A Vance
- Oak Ridge Institute for Science and Education Research Participation Program, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Mette C Schladweiler
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Paul A Evansky
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Andres R Henriquez
- Oak Ridge Institute for Science and Education Research Participation Program, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Rachel Grindstaff
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Stephen H Gavett
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, US Environmental Protection Agency, Research Triangle Park, NC, United States
| | - Urmila P Kodavanti
- Public Health and Integrated Toxicology Division, Center for Public Health and Environmental Assessment, US Environmental Protection Agency, Research Triangle Park, NC, United States.
| |
Collapse
|
2
|
Achanta S, Jordt SE. Transient receptor potential channels in pulmonary chemical injuries and as countermeasure targets. Ann N Y Acad Sci 2020; 1480:73-103. [PMID: 32892378 PMCID: PMC7933981 DOI: 10.1111/nyas.14472] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 07/22/2020] [Accepted: 07/29/2020] [Indexed: 12/17/2022]
Abstract
The lung is highly sensitive to chemical injuries caused by exposure to threat agents in industrial or transportation accidents, occupational exposures, or deliberate use as weapons of mass destruction (WMD). There are no antidotes for the majority of the chemical threat agents and toxic inhalation hazards despite their use as WMDs for more than a century. Among several putative targets, evidence for transient receptor potential (TRP) ion channels as mediators of injury by various inhalational chemical threat agents is emerging. TRP channels are expressed in the respiratory system and are essential for homeostasis. Among TRP channels, the body of literature supporting essential roles for TRPA1, TRPV1, and TRPV4 in pulmonary chemical injuries is abundant. TRP channels mediate their function through sensory neuronal and nonneuronal pathways. TRP channels play a crucial role in complex pulmonary pathophysiologic events including, but not limited to, increased intracellular calcium levels, signal transduction, recruitment of proinflammatory cells, neurogenic inflammatory pathways, cough reflex, hampered mucus clearance, disruption of the integrity of the epithelia, pulmonary edema, and fibrosis. In this review, we summarize the role of TRP channels in chemical threat agents-induced pulmonary injuries and how these channels may serve as medical countermeasure targets for broader indications.
Collapse
Affiliation(s)
- Satyanarayana Achanta
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
| | - Sven-Eric Jordt
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, North Carolina
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| |
Collapse
|
3
|
Stevens JS, Padilla S, DeMarini DM, Hunter DL, Martin WK, Thompson LC, Gilmour MI, Hazari MS, Farraj AK. Zebrafish Locomotor Responses Reveal Irritant Effects of Fine Particulate Matter Extracts and a Role for TRPA1. Toxicol Sci 2019; 161:290-299. [PMID: 29048608 DOI: 10.1093/toxsci/kfx217] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Exposure to fine particulate matter (PM) air pollution causes adverse cardiopulmonary outcomes. Yet, the limited capacity to readily identify contributing PM sources and associated PM constituents in any given ambient air shed impedes risk assessment efforts. The health effects of PM have been attributed in part to its capacity to elicit irritant responses. A variety of chemicals trigger irritant behavior responses in zebrafish that can be easily measured. The purposes of this study were to examine the utility of zebrafish locomotor responses in the toxicity assessment of fine PM and its chemical fractions and uncover mechanisms of action. Locomotor responses were recorded in 6-day-old zebrafish exposed for 60 min in the dark at 26 °C to the extractable organic matter of a compressor-generated diesel exhaust PM (C-DEP) and 4 of its fractions (F1-F4) containing varying chemical classes of increasing polarity. The role of the transient receptor potential (TRP) cation channel TRPA1, a chemical sensor in mammals and zebrafish, in locomotor responses to C-DEP, was also examined. Acrolein, an environmental irritant and known activator of TRPA1, and all extracts induced concentration-dependent locomotor responses whose potencies ranked as follows: polar F3 > weakly polar F2 > C-DEP > highly polar F4 > nonpolar F1, indicating that polar and weakly polar fractions that included nitro- and oxy-polyaromatic hydrocarbons (PAHs), drove C-DEP responses. Irritant potencies in fish positively correlated with mutagenic potencies of the same extracts in strains of Salmonella sensitive to nitro- and oxy-PAHs, further implicating these chemical classes in the zebrafish responses to C-DEP. Pharmacologic inhibition of TRPA1 blocked locomotor responses to acrolein and the extracts. Taken together, these data indicate that the zebrafish locomotor assay may help expedite toxicity screening of fine PM sources, identify causal chemical classes, and uncover plausible biological mechanisms.
Collapse
Affiliation(s)
- Joey S Stevens
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37830
| | | | | | | | - W Kyle Martin
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee 37830
| | - Leslie C Thompson
- Environmental Public Health Division, USEPA, Research Triangle Park, North Carolina 27711
| | - M Ian Gilmour
- Environmental Public Health Division, USEPA, Research Triangle Park, North Carolina 27711
| | - Mehdi S Hazari
- Environmental Public Health Division, USEPA, Research Triangle Park, North Carolina 27711
| | - Aimen K Farraj
- Environmental Public Health Division, USEPA, Research Triangle Park, North Carolina 27711
| |
Collapse
|
4
|
Snow SJ, McGee MA, Henriquez A, Richards JE, Schladweiler MC, Ledbetter AD, Kodavanti UP. Respiratory Effects and Systemic Stress Response Following Acute Acrolein Inhalation in Rats. Toxicol Sci 2017; 158:454-464. [PMID: 28541489 PMCID: PMC6515527 DOI: 10.1093/toxsci/kfx108] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Previous studies have demonstrated that exposure to the pulmonary irritant ozone causes myriad systemic metabolic and pulmonary effects attributed to sympathetic and hypothalamus-pituitary-adrenal (HPA) axis activation, which are exacerbated in metabolically impaired models. We examined respiratory and systemic effects following exposure to a sensory irritant acrolein to elucidate the systemic and pulmonary consequences in healthy and diabetic rat models. Male Wistar and Goto Kakizaki (GK) rats, a nonobese type II diabetic Wistar-derived model, were exposed by inhalation to 0, 2, or 4 ppm acrolein, 4 h/d for 1 or 2 days. Exposure at 4 ppm significantly increased pulmonary and nasal inflammation in both strains with vascular protein leakage occurring only in the nose. Acrolein exposure (4 ppm) also caused metabolic impairment by inducing hyperglycemia and glucose intolerance (GK > Wistar). Serum total cholesterol (GKs only), low-density lipoprotein (LDL) cholesterol (both strains), and free fatty acids (GK > Wistar) levels increased; however, no acrolein-induced changes were noted in branched-chain amino acid or insulin levels. These responses corresponded with a significant increase in corticosterone and modest but insignificant increases in adrenaline in both strains, suggesting activation of the HPA axis. Collectively, these data demonstrate that acrolein exposure has a profound effect on nasal and pulmonary inflammation, as well as glucose and lipid metabolism, with the systemic effects exacerbated in the metabolically impaired GKs. These results are similar to ozone-induced responses with the exception of lung protein leakage and ability to alter branched-chain amino acid and insulin levels, suggesting some differences in neuroendocrine regulation of these two air pollutants.
Collapse
Affiliation(s)
- Samantha J. Snow
- Environmental Public Health Division, NHEERL, US Environmental Protection Agency, Durham, North Carolina
| | - Marie A. McGee
- Oak Ridge Institute for Science and Education, Durham, North Carolina
| | - Andres Henriquez
- Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Judy E. Richards
- Environmental Public Health Division, NHEERL, US Environmental Protection Agency, Durham, North Carolina
| | - Mette C. Schladweiler
- Environmental Public Health Division, NHEERL, US Environmental Protection Agency, Durham, North Carolina
| | - Allen D. Ledbetter
- Environmental Public Health Division, NHEERL, US Environmental Protection Agency, Durham, North Carolina
| | - Urmila P. Kodavanti
- Environmental Public Health Division, NHEERL, US Environmental Protection Agency, Durham, North Carolina
- Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| |
Collapse
|
5
|
Achanta S, Jordt SE. TRPA1: Acrolein meets its target. Toxicol Appl Pharmacol 2017; 324:45-50. [PMID: 28284857 DOI: 10.1016/j.taap.2017.03.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 03/07/2017] [Indexed: 12/29/2022]
Affiliation(s)
- Satyanarayana Achanta
- Department of Anesthesiology, Duke University School of Medicine, Durham, NC 27710, United States
| | - Sven-Eric Jordt
- Department of Anesthesiology, Duke University School of Medicine, Durham, NC 27710, United States; Yale Tobacco Center of Regulatory Science (TCORS), Department of Psychiatry, Yale School of Medicine, New Haven, CT 06519, United States.
| |
Collapse
|
6
|
Rothenberg C, Achanta S, Svendsen ER, Jordt SE. Tear gas: an epidemiological and mechanistic reassessment. Ann N Y Acad Sci 2016; 1378:96-107. [PMID: 27391380 PMCID: PMC5096012 DOI: 10.1111/nyas.13141] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 05/15/2016] [Accepted: 05/20/2016] [Indexed: 12/19/2022]
Abstract
Deployments of tear gas and pepper spray have rapidly increased worldwide. Large amounts of tear gas have been used in densely populated cities, including Cairo, Istanbul, Rio de Janeiro, Manama (Bahrain), and Hong Kong. In the United States, tear gas was used extensively during recent riots in Ferguson, Missouri. Whereas tear gas deployment systems have rapidly improved-with aerial drone systems tested and requested by law enforcement-epidemiological and mechanistic research have lagged behind and have received little attention. Case studies and recent epidemiological studies revealed that tear gas agents can cause lung, cutaneous, and ocular injuries, with individuals affected by chronic morbidities at high risk for complications. Mechanistic studies identified the ion channels TRPV1 and TRPA1 as targets of capsaicin in pepper spray, and of the tear gas agents chloroacetophenone, CS, and CR. TRPV1 and TRPA1 localize to pain-sensing peripheral sensory neurons and have been linked to acute and chronic pain, cough, asthma, lung injury, dermatitis, itch, and neurodegeneration. In animal models, transient receptor potential inhibitors show promising effects as potential countermeasures against tear gas injuries. On the basis of the available data, a reassessment of the health risks of tear gas exposures in the civilian population is advised, and development of new countermeasures is proposed.
Collapse
Affiliation(s)
- Craig Rothenberg
- Department of Global Environmental Health Sciences, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana
| | - Satyanarayana Achanta
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina
| | - Erik R Svendsen
- Division of Environmental Health, Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina
| | - Sven-Eric Jordt
- Department of Anesthesiology, Duke University School of Medicine, Durham, North Carolina.
| |
Collapse
|
7
|
Bodkin JV, Thakore P, Aubdool AA, Liang L, Fernandes ES, Nandi M, Spina D, Clark JE, Aaronson PI, Shattock MJ, Brain SD. Investigating the potential role of TRPA1 in locomotion and cardiovascular control during hypertension. Pharmacol Res Perspect 2014; 2:e00052. [PMID: 25505598 PMCID: PMC4186440 DOI: 10.1002/prp2.52] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Revised: 04/23/2014] [Accepted: 04/24/2014] [Indexed: 12/23/2022] Open
Abstract
Radiotelemetry was used to investigate the in vivo cardiovascular and activity phenotype of both TRPA1 (transient receptor potential ankyrin 1) wild-type (WT) and TRPA1 knockout (KO) mice. After baseline recording, experimental hypertension was induced using angiotensin II infusion (1.1 mg(-1) kg(-1) a day, for 14 days). TRPA1 WT and KO mice showed similar morphological and functional cardiovascular parameters, including similar basal blood pressure (BP), heart rate, size, and function. Similar hypertension was also displayed in response to angiotensin II (156 ± 7 and 165 ± 11 mmHg, systolic BP ± SEM, n = 5-6). TRPA1 KO mice showed increased hypertensive hypertrophy (heart weight:tibia length: 7.3 ± 1.6 mg mm(-1) vs. 8.8 ± 1.7 mg mm(-1)) and presented with blunted interleukin 6 (IL-6) production compared with hypertensive WT mice (151 ± 24 vs. 89 ± 16 pg mL(-1)). TRPA1 expression in dorsal root ganglion (DRG) neurones was upregulated during hypertension (163% of baseline expression). Investigations utilizing the TRPA1 agonist cinnamaldehyde (CA) on mesenteric arterioles isolated from näive mice suggested a lack of TRPA1-dependent vasoreactivity in this vascular bed; a site with notable ability to alter total peripheral resistance. However, mesenteric arterioles isolated from TRPA1 KO hypertensive mice displayed significantly reduced ability to relax in response to nitric oxide (NO) (P < 0.05). Unexpectedly, naïve TRPA1 KO mice also displayed physical hyperactivity traits at baseline, which was exacerbated during hypertension. In conclusion, our study provides a novel cardiovascular characterization of TRPA1 KO mice in a model of hypertension. Results suggest that TRPA1 has a limited role in global cardiovascular control, but we demonstrate an unexpected capacity for TRPA1 to regulate physical activity.
Collapse
Affiliation(s)
- Jennifer V Bodkin
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K
| | - Pratish Thakore
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K ; Pharmaceutical Sciences Division, School of Biomedical Sciences, King's College London London, SE1 9NH, U.K
| | - Aisah A Aubdool
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K
| | - Lihuan Liang
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K
| | - Elizabeth S Fernandes
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K ; Programa de Pós-Graduação em Biologia Parasitária, Universidade Ceuma São Luís, Brazil
| | - Manasi Nandi
- Pharmaceutical Sciences Division, School of Biomedical Sciences, King's College London London, SE1 9NH, U.K
| | - Domenico Spina
- Pharmaceutical Sciences Division, School of Biomedical Sciences, King's College London London, SE1 9NH, U.K
| | - James E Clark
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K
| | - Philip I Aaronson
- Asthma, Allergy and Lung Biology Division, School of Medicine, King's College London London, SE1 1UL, U.K
| | - Michael J Shattock
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K
| | - Susan D Brain
- Cardiovascular Division, BHF Centre of Excellence and Centre of Integrative Biomedicine, School of Medicine, King's College London London, SE1 9NH, U.K
| |
Collapse
|
8
|
Morris JB, Cichocki JA, Smith GJ. In situ measurement of vapor uptake in the rodent upper respiratory tract. ACTA ACUST UNITED AC 2013; Chapter 24:Unit 24.1. [PMID: 23408196 DOI: 10.1002/0471140856.tx2401s55] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The response of respiratory tract tissue target sites to inhaled vapors depends on the amount of inhaled vapor that is delivered to those sites. Direct measurement of vapor absorption within a specific airway of the living animal requires that the airway be isolated, which currently can only be performed on the upper airways. Towards this end, the upper respiratory tract (all airways anterior to the larynx) is surgically isolated in the anesthetized rat by tracheostomy and insertion of two endotracheal tubes, one leading anteriorly and the other posteriorly. The surgically manipulated animal is then placed in a nose-only inhalation chamber and test-vapor-laden air is drawn through the isolated upper airways under defined air flow conditions via the anterior endotracheal tube. The animal spontaneously respires clean air into the lungs during this procedure via the posterior endotracheal tube. The concentration of test vapor in air entering and the air exiting the upper airways is measured by gas chromatography, and the difference in concentrations provides a measure of vapor absorption in that site. A rich database is available on upper respiratory tract vapor absorption as measured by this methodology, to which newly obtained data can be compared. These data have been instrumental not only in understanding the regional airway toxicity of inspired vapors, but also for developing mathematical models to describe inhaled vapor dosimetry.
Collapse
Affiliation(s)
- John B Morris
- Toxicology Program, Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut, USA
| | | | | |
Collapse
|
9
|
Alejo DM, Moraes MP, Liao X, Dias CC, Tulman ER, Diaz-San Segundo F, Rood D, Grubman MJ, Silbart LK. An adenovirus vectored mucosal adjuvant augments protection of mice immunized intranasally with an adenovirus-vectored foot-and-mouth disease virus subunit vaccine. Vaccine 2013; 31:2302-9. [PMID: 23499593 DOI: 10.1016/j.vaccine.2013.02.060] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 02/08/2013] [Accepted: 02/27/2013] [Indexed: 11/30/2022]
Abstract
Foot-and-mouth disease virus (FMDV) is a highly contagious pathogen that causes severe morbidity and economic losses to the livestock industry in many countries. The oral and respiratory mucosae are the main ports of entry of FMDV, so the stimulation of local immunity in these tissues may help prevent initial infection and viral spread. E. coli heat-labile enterotoxin (LT) has been described as one of the few molecules that have adjuvant activity at mucosal surfaces. The objective of this study was to evaluate the efficacy of replication-defective adenovirus 5 (Ad5) vectors encoding either of two LT-based mucosal adjuvants, LTB or LTR72. These vectored adjuvants were delivered intranasally to mice concurrent with an Ad5-FMDV vaccine (Ad5-A24) to assess their ability to augment mucosal and systemic humoral immune responses to Ad5-A24 and protection against FMDV. Mice receiving Ad5-A24 plus Ad5-LTR72 had higher levels of mucosal and systemic neutralizing antibodies than those receiving Ad5-A24 alone or Ad5-A24 plus Ad5-LTB. The vaccine plus Ad5-LTR72 group also demonstrated 100% survival after intradermal challenge with a lethal dose of homologous FMDV serotype A24. These results suggest that Ad5-LTR72 could be used as an important tool to enhance mucosal and systemic immunity against FMDV and potentially other pathogens with a common route of entry.
Collapse
Affiliation(s)
- Diana M Alejo
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, United States
| | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Abstract
Acrolein is a respiratory irritant that can be generated during cooking and is in environmental tobacco smoke. More plentiful in cigarette smoke than polycyclic aromatic hydrocarbons (PAH), acrolein can adduct tumor suppressor p53 (TP53) DNA and may contribute to TP53-mutations in lung cancer. Acrolein is also generated endogenously at sites of injury, and excessive breath levels (sufficient to activate metalloproteinases and increase mucin transcripts) have been detected in asthma and chronic obstructive pulmonary disease (COPD). Because of its reactivity with respiratory-lining fluid or cellular macromolecules, acrolein alters gene regulation, inflammation, mucociliary transport, and alveolar-capillary barrier integrity. In laboratory animals, acute exposures have lead to acute lung injury and pulmonary edema similar to that produced by smoke inhalation whereas lower concentrations have produced bronchial hyperreactivity, excessive mucus production, and alveolar enlargement. Susceptibility to acrolein exposure is associated with differential regulation of cell surface receptor, transcription factor, and ubiquitin-proteasome genes. Consequent to its pathophysiological impact, acrolein contributes to the morbidly and mortality associated with acute lung injury and COPD, and possibly asthma and lung cancer.
Collapse
Affiliation(s)
- Kiflai Bein
- Department of Environmental and Occupational Health, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15219-3130, USA.
| | | |
Collapse
|
11
|
Taylor-Clark TE, Undem BJ. Sensing pulmonary oxidative stress by lung vagal afferents. Respir Physiol Neurobiol 2011; 178:406-13. [PMID: 21600314 DOI: 10.1016/j.resp.2011.05.003] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 04/06/2011] [Accepted: 05/04/2011] [Indexed: 12/30/2022]
Abstract
Oxidative stress in the bronchopulmonary airways can occur through a variety of inflammatory mechanisms and also following the inhalation of environmental pollutants. Oxidative stress causes cellular dysfunction and thus mammals (including humans) have developed mechanisms for detecting oxidative stress, such that defensive behavior and defensive biological mechanisms can be induced to lessen its potential damage. Vagal sensory nerves innervating the airways play a critical role in the detection of the microenvironment in the airways. Oxidative stress and associated compounds activate unmyelinated bronchopulmonary C-fibers, initiating action potentials in these nerves that conduct centrally to evoke unpleasant sensations (e.g. urge to cough, dyspnea, chest-tightness) and to stimulate/modulate reflexes (e.g. cough, bronchoconstriction, respiratory rate, inspiratory drive). This review will summarize the published evidence regarding the mechanisms by which oxidative stress, reactive oxygen species, environmental pollutants and lipid products of peroxidation activate bronchopulmonary C-fibers. Evidence suggests a key role for transient receptor potential ankyrin 1 (TRPA1), although transient receptor potential vanilloid 1 (TRPV1) and purinergic P2X channels may also play a role. Knowledge of these pathways greatly aids our understanding of the role of oxidative stress in health and disease and represents novel therapeutic targets for diseases of the airways.
Collapse
Affiliation(s)
- Thomas E Taylor-Clark
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL 33612, United States.
| | | |
Collapse
|
12
|
Kunkler PE, Ballard CJ, Oxford GS, Hurley JH. TRPA1 receptors mediate environmental irritant-induced meningeal vasodilatation. Pain 2010; 152:38-44. [PMID: 21075522 DOI: 10.1016/j.pain.2010.08.021] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 07/01/2010] [Accepted: 08/16/2010] [Indexed: 10/18/2022]
Abstract
The TRPA1 receptor is a member of the transient receptor potential (TRP) family of ion channels expressed in nociceptive neurons. TRPA1 receptors are targeted by pungent compounds from mustard and garlic and environmental irritants such as formaldehyde and acrolein. Ingestion or inhalation of these chemical agents causes irritation and burning in the nasal and oral mucosa and respiratory lining. Headaches have been widely reported to be induced by inhalation of environmental irritants, but it is unclear how these agents produce headache. Stimulation of trigeminal neurons releases CGRP and substance P and induces neurogenic inflammation associated with the pain of migraine. Here we test the hypothesis that activation of TRPA1 receptors is the mechanistic link between environmental irritants and peptide-mediated neurogenic inflammation. Known TRPA1 agonists and environmental irritants stimulate CGRP release from dissociated rat trigeminal ganglia neurons and this release is blocked by a selective TRPA1 antagonist, HC-030031. Further, TRPA1 agonists and environmental irritants increase meningeal blood flow following intranasal administration. Prior dural application of the CGRP antagonist, CGRP(8-37), or intranasal or dural administration of HC-030031, blocks the increases in blood flow elicited by environmental irritants. Together these results demonstrate that TRPA1 receptor activation by environmental irritants stimulates CGRP release and increases cerebral blood flow. We suggest that these events contribute to headache associated with environmental irritants.
Collapse
Affiliation(s)
- Phillip Edward Kunkler
- The Department of Biochemistry and Molecular Biology, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA The Department of Pharmacology and Toxicology, Stark Neurosciences Research Institute, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | | | | | | |
Collapse
|
13
|
Lee HM, Hallberg LM, Greeley GH, Englander EW. Differential inhibition of mitochondrial respiratory complexes by inhalation of combustion smoke and carbon monoxide, in vivo, in the rat brain. Inhal Toxicol 2010; 22:770-7. [PMID: 20429857 DOI: 10.3109/08958371003770315] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Combustion smoke contains gases and particulates, which act via hypoxia and cytotoxicity producing mechanisms to injure cells and tissues. While carbon monoxide (CO) is the major toxicant in smoke, its toxicity is exacerbated in the presence of other compounds. Here, we examined modulations of mitochondrial and cytosolic energy metabolism by inhalation of combustion smoke versus CO, in vivo, in the rat brain. Measurements revealed reduced activities of respiratory chain (RC) complexes, with greater inhibition by smoke than equivalent CO in ambient air. In the case of RC complex IV, inhibition by CO and smoke was similar--suggesting that complex IV inhibition is primarily by the action of CO. In contrast, inhibition of complexes I and III was greater by smoke. Increases in cytosolic lactate dehydrogenase and pyruvate kinase activities accompanied inhibition of RC complexes, likely reflecting compensatory increases in cytosolic energy production. Together, the data provide new insights into the mechanisms of smoke inhalation-induced perturbations of brain energetics, which impact neuronal function and contribute to the development of neuropathologies in survivors of exposures to CO and combustion smoke.
Collapse
Affiliation(s)
- Heung M Lee
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555-1220, USA
| | | | | | | |
Collapse
|
14
|
Inoue T, Bryant BP. Multiple cation channels mediate increases in intracellular calcium induced by the volatile irritant, trans-2-pentenal in rat trigeminal neurons. Cell Mol Neurobiol 2009; 30:35-41. [PMID: 19568926 DOI: 10.1007/s10571-009-9428-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2009] [Accepted: 06/15/2009] [Indexed: 10/20/2022]
Abstract
Trans-2-Pentenal (pentenal), an alpha,beta-unsaturated aldehyde, induces increases in [Ca(2+)](i) in cultured neonatal rat trigeminal ganglion (TG) neurons. Since all pentenal-sensitive neurons responded to a specific TRPA1 agonist, allyl isothiocyanate (AITC) and neurons from TRPA1 knockouts failed to respond to pentenal, TRPA1 appears to be sole initial transduction site for pentenal-evoked trigeminal response, as reported for the structurally related irritant, acrolein. Furthermore, because the neuronal sensitivity to pentenal is strictly dependent upon the presence of extracellular Na(+)/Ca(2+), as we showed previously, we investigated which types of voltage-gated sodium/calcium channels (VGSCs/VGCCs) are involved in pentenal-induced [Ca(2+)](i) increases as a downstream mechanisms. The application of tetrodotoxin (TTX) significantly suppressed the pentenal-induced increase in [Ca(2+)](i) in a portion of TG neurons, suggesting that TTX-sensitive (TTXs) VGSCs contribute to the pentenal response in those neurons. Diltiazem and omega-agatoxin IVA, antagonists of L- and P/Q-type VGCCs, respectively, both caused significant reductions of the pentenal-induced responses. omega-Conotoxin GVIA, on the other hand, caused only a small decrease in the size of pentenal-induced [Ca(2+)](i) rise. These indicate that both L- and P/Q-type VGCCs are involved in the increase in [Ca(2+)](i) produced by pentenal, while N-type calcium channels play only a minor role. This study demonstrates that TTXs VGSCs, L- and P/Q-type VGCCs play a significant role in the pentenal-induced trigeminal neuronal responses as downstream mechanisms following TRPA1 activation.
Collapse
Affiliation(s)
- Takashi Inoue
- Tobacco Science Research Center, Japan Tobacco Inc., Yokohama, Kanagawa, 227-8512, Japan.
| | | |
Collapse
|
15
|
Faroon O, Roney N, Taylor J, Ashizawa A, Lumpkin MH, Plewak DJ. Acrolein health effects. Toxicol Ind Health 2009; 24:447-90. [PMID: 19028774 DOI: 10.1177/0748233708094188] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Acrolein is a chemical used as an intermediate reactive aldehyde in chemical industry. It is used for synthesis of many organic substances, methionine production, and methyl chloride refrigerant. The general population is exposed to acrolein via smoking, second-hand smoke, exposure to wood and plastic smoke. Firefighters and population living or working in areas with heavy automotive traffic may expose to higher level of acrolein via inhalation of smoke or automotive exhaust. Degradation of acrolein in all environmental media occurs rapidly, therefore, environmental accumulation is not expected. Acrolein degrade in 6A days when applied to surface water, and it has not been found as a contaminant in municipal drinking water. Acrolein vapor may cause eye, nasal and respiratory tract irritations in low level exposure. A decrease in breathing rate was reported by volunteers acutely exposed to 0.3A ppm of acrolein. At similar level, mild nasal epithelial dysplasia, necrosis, and focal basal cell metaplasia have been observed in rats. The acrolein effects on gastrointestinal mucosa in the animals include epithelial hyperplasia, ulceration, and hemorrhage. The severity of the effects is dose dependent. Acrolein induces the respiratory, ocular, and gastrointestinal irritations by inducing the release of peptides in nerve terminals innervating these systems. Levels of acrolein between 22 and 249 ppm for 10 min induced a dose-related decrease in substance P (a short-chain polypeptide that functions as a neurotransmitter or neuromodulator).
Collapse
Affiliation(s)
- O Faroon
- ATSDR, Division of Toxicology and Environmental Medicine, Atlanta, Georgia, USA.
| | | | | | | | | | | |
Collapse
|
16
|
Bessac BF, Jordt SE. Breathtaking TRP channels: TRPA1 and TRPV1 in airway chemosensation and reflex control. Physiology (Bethesda) 2009; 23:360-70. [PMID: 19074743 DOI: 10.1152/physiol.00026.2008] [Citation(s) in RCA: 289] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
New studies have revealed an essential role for TRPA1, a sensory neuronal TRP ion channel, in airway chemosensation and inflammation. TRPA1 is activated by chlorine, reactive oxygen species, and noxious constituents of smoke and smog, initiating irritation and airway reflex responses. Together with TRPV1, the capsaicin receptor, TRPA1 may contribute to chemical hypersensitivity, chronic cough, and airway inflammation in asthma, COPD, and reactive airway dysfunction syndrome.
Collapse
Affiliation(s)
- Bret F Bessac
- Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut, USA
| | | |
Collapse
|
17
|
Taylor-Clark TE, Kiros F, Carr MJ, McAlexander MA. Transient receptor potential ankyrin 1 mediates toluene diisocyanate-evoked respiratory irritation. Am J Respir Cell Mol Biol 2008; 40:756-62. [PMID: 19059884 DOI: 10.1165/rcmb.2008-0292oc] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Toluene diisocyanate (TDI), a reactive, hazardous irritant, causes respiratory symptoms such as cough, rhinitis, dyspnea, and chest tightness in exposed workers. Although previous animal studies have shown that TDI causes respiratory reflexes that are abolished by desensitization of capsaicin-sensitive sensory nerves, the specific molecular identity of the transducer(s) responsible for sensing this noxious stimulus has, to date, remained elusive. Recent studies have demonstrated that transient receptor potential ankyrin 1 (TRPA1), an ion channel largely restricted to a subset of capsaicin-sensitive sensory nerves, functions as a transducer capable of initiating reflex responses to many reactive chemical stimuli. We therefore hypothesized that TRPA1 is the primary molecular transducer through which TDI causes sensory nerve activation and respiratory reflexes. Consistent with this hypothesis, TDI activated TRPA1, but not the capsaicin-sensitive transient receptor potential vanilloid 1 channel, in heterologous expression systems. TDI also activated a subset of dissociated trigeminal sensory neurons from wild-type but not TRPA1-deficient mice. In vivo, TDI mimicked known TRPA1 agonists by causing a pronounced decrease in breathing rate, indicative of respiratory sensory irritation, and this reflex was abolished in TRPA1-deficient mice. Together, our data suggest that TDI causes sensory nerve activation and airway sensory irritation via the activation of the ion channel, TRPA1.
Collapse
Affiliation(s)
- Thomas E Taylor-Clark
- Division of Allergy and Clinical Immunology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | | | | |
Collapse
|
18
|
Bessac BF, Sivula M, von Hehn CA, Caceres AI, Escalera J, Jordt SE. Transient receptor potential ankyrin 1 antagonists block the noxious effects of toxic industrial isocyanates and tear gases. FASEB J 2008; 23:1102-14. [PMID: 19036859 DOI: 10.1096/fj.08-117812] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The release of methyl isocyanate in Bhopal, India, caused the worst industrial accident in history. Exposures to industrial isocyanates induce lacrimation, pain, airway irritation, and edema. Similar responses are elicited by chemicals used as tear gases. Despite frequent exposures, the biological targets of isocyanates and tear gases in vivo have not been identified, precluding the development of effective countermeasures. We use Ca(2+) imaging and electrophysiology to show that the noxious effects of isocyanates and those of all major tear gas agents are caused by activation of Ca(2+) influx and membrane currents in mustard oil-sensitive sensory neurons. These responses are mediated by transient receptor potential ankyrin 1 (TRPA1), an ion channel serving as a detector for reactive chemicals. In mice, genetic ablation or pharmacological inhibition of TRPA1 dramatically reduces isocyanate- and tear gas-induced nocifensive behavior after both ocular and cutaneous exposures. We conclude that isocyanates and tear gas agents target the same neuronal receptor, TRPA1. Treatment with TRPA1 antagonists may prevent and alleviate chemical irritation of the eyes, skin, and airways and reduce the adverse health effects of exposures to a wide range of toxic noxious chemicals.
Collapse
Affiliation(s)
- Bret F Bessac
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
| | | | | | | | | | | |
Collapse
|
19
|
McAlexander MA, Carr MJ. Peripheral mechanisms I: plasticity of peripheral pathways. Handb Exp Pharmacol 2008:129-54. [PMID: 18825339 DOI: 10.1007/978-3-540-79842-2_7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cough plays a vital role in protecting the lower airways from inhaled irritants, pollutants, and infectious agents. The cough reflex exhibits remarkable plasticity, such that in the context of infectious or inflammatory respiratory diseases such as asthma, chronic bronchitis, and idiopathic pulmonary fibrosis the cough reflex can become dysregulated, leading to a chronic cough. A chronic, nonproductive (dry) cough can rob sufferers of quality of life. Plasticity of the cough reflex likely involves multiple intersecting pathways within the airways, the peripheral nerves that supply them, and the central nervous system. While further studies are needed to determine the presence and relevance of many of these specific pathways in cough associated with chronic respiratory disease, the last decade has yielded unprecedented insight into the molecular identity of the ion channels and associated proteins that initiate and conduct action potentials in the primary sensory nerves involved in reflexes such as cough. We now know, for instance, that members of the transient receptor potential superfamily of nonselective cation channels function as transducers that convert specific external stimuli into neuronal activation. We also know that certain Na+ and K+ channels play specialized roles in regulating action potential discharge in irritant-sensing afferent nerves. In this chapter, we summarize the available information regarding factors that may modulate afferent neuron function acutely, via posttranslational modifications and over the longer term through neurotrophin-dependent alterations of the transcriptional programs of adult sensory neurons.
Collapse
Affiliation(s)
- M A McAlexander
- GlaxoSmithKline, 709 Swedeland Rd, King of Prussia, PA 19406, USA
| | | |
Collapse
|
20
|
Morris JB, Hubbs AF. Inhalation dosimetry of diacetyl and butyric acid, two components of butter flavoring vapors. Toxicol Sci 2008; 108:173-83. [PMID: 18940962 DOI: 10.1093/toxsci/kfn222] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Occupational exposure to butter flavoring vapors (BFV) is associated with significant pulmonary injury. The goal of the current study was to characterize inhalation dosimetric patterns of diacetyl and butyric acid, two components of BFV, and to develop a hybrid computational fluid dynamic-physiologically based pharmacokinetic model (CFD-PBPK) to describe these patterns. Uptake of diacetyl and butyric acid vapors, alone and in combination, was measured in the upper respiratory tract of anesthetized male Sprague-Dawley rats under constant velocity flow conditions and the uptake data were used to validate the CFD-PBPK model. Diacetyl vapor (100 or 300 ppm) was scrubbed from the airstream with 76-36% efficiency at flows of 100-400 ml/min. Butryic acid (30 ppm) was scrubbed with >90% efficiency. Concurrent exposure to butyric acid resulted in a small but significant reduction of diacetyl uptake (36 vs. 31%, p < 0.05). Diacetyl was metabolized in nasal tissues in vitro, likely by diacetyl reductase, an enzyme known to be inhibited by butyric acid. The CFD-PBPK model closely described diacetyl uptake; the reduction in diacetyl uptake by butyric acid could be explained by inhibition of diacetyl reductase. Extrapolation to the human via the model suggested that inspired diacetyl may penetrate to the intrapulmonary airways to a greater degree in the human than in the rat. Thus, based on dosimetric relationships, extrapulmonary airway injury in the rat may be predictive of intrapulmonary airway injury in humans. Butyric acid may modulate diacetyl toxicity by inhibiting its metabolism and/or altering its inhalation dosimetric patterns.
Collapse
Affiliation(s)
- John B Morris
- Toxicology Program, Department of Pharmaceutical Sciences, University of Connecticut, Storrs, Connecticut 06269, USA.
| | | |
Collapse
|
21
|
Kasahara DI, Poynter ME, Othman Z, Hemenway D, van der Vliet A. Acrolein inhalation suppresses lipopolysaccharide-induced inflammatory cytokine production but does not affect acute airways neutrophilia. THE JOURNAL OF IMMUNOLOGY 2008; 181:736-45. [PMID: 18566440 DOI: 10.4049/jimmunol.181.1.736] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Acrolein is a reactive unsaturated aldehyde that is produced during endogenous oxidative processes and is a major bioactive component of environmental pollutants such as cigarette smoke. Because in vitro studies demonstrate that acrolein can inhibit neutrophil apoptosis, we evaluated the effects of in vivo acrolein exposure on acute lung inflammation induced by LPS. Male C57BL/6J mice received 300 microg/kg intratracheal LPS and were exposed to acrolein (5 parts per million, 6 h/day), either before or after LPS challenge. Exposure to acrolein either before or after LPS challenge did not significantly affect the overall extent of LPS-induced lung inflammation, or the duration of the inflammatory response, as observed from recovered lung lavage leukocytes and histology. However, exposure to acrolein after LPS instillation markedly diminished the LPS-induced production of several inflammatory cytokines, specifically TNF-alpha, IL-12, and the Th1 cytokine IFN-gamma, which was associated with reduction in NF-kappaB activation. Our data demonstrate that acrolein exposure suppresses LPS-induced Th1 cytokine responses without affecting acute neutrophilia. Disruption of cytokine signaling by acrolein may represent a mechanism by which smoking contributes to chronic disease in chronic obstructive pulmonary disease and asthma.
Collapse
Affiliation(s)
- David Itiro Kasahara
- Department of Pathology, Vermont Lung Center, College of Medicine, University of Vermont, Burlington, VT 05405, USA
| | | | | | | | | |
Collapse
|
22
|
Bessac BF, Sivula M, von Hehn CA, Escalera J, Cohn L, Jordt SE. TRPA1 is a major oxidant sensor in murine airway sensory neurons. J Clin Invest 2008; 118:1899-910. [PMID: 18398506 DOI: 10.1172/jci34192] [Citation(s) in RCA: 343] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2007] [Accepted: 02/13/2008] [Indexed: 11/17/2022] Open
Abstract
Sensory neurons in the airways are finely tuned to respond to reactive chemicals threatening airway function and integrity. Nasal trigeminal nerve endings are particularly sensitive to oxidants formed in polluted air and during oxidative stress as well as to chlorine, which is frequently released in industrial and domestic accidents. Oxidant activation of airway neurons induces respiratory depression, nasal obstruction, sneezing, cough, and pain. While normally protective, chemosensory airway reflexes can provoke severe complications in patients affected by inflammatory airway conditions like rhinitis and asthma. Here, we showed that both hypochlorite, the oxidizing mediator of chlorine, and hydrogen peroxide, a reactive oxygen species, activated Ca(2+) influx and membrane currents in an oxidant-sensitive subpopulation of chemosensory neurons. These responses were absent in neurons from mice lacking TRPA1, an ion channel of the transient receptor potential (TRP) gene family. TRPA1 channels were strongly activated by hypochlorite and hydrogen peroxide in primary sensory neurons and heterologous cells. In tests of respiratory function, Trpa1(-/-) mice displayed profound deficiencies in hypochlorite- and hydrogen peroxide-induced respiratory depression as well as decreased oxidant-induced pain behavior. Our results indicate that TRPA1 is an oxidant sensor in sensory neurons, initiating neuronal excitation and subsequent physiological responses in vitro and in vivo.
Collapse
Affiliation(s)
- Bret F Bessac
- Department of Pharmacology and Section of Pulmonary and Critical Care Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, USA
| | | | | | | | | | | |
Collapse
|
23
|
Bousquet J, Khaltaev N, Cruz AA, Denburg J, Fokkens WJ, Togias A, Zuberbier T, Baena-Cagnani CE, Canonica GW, van Weel C, Agache I, Aït-Khaled N, Bachert C, Blaiss MS, Bonini S, Boulet LP, Bousquet PJ, Camargos P, Carlsen KH, Chen Y, Custovic A, Dahl R, Demoly P, Douagui H, Durham SR, van Wijk RG, Kalayci O, Kaliner MA, Kim YY, Kowalski ML, Kuna P, Le LTT, Lemiere C, Li J, Lockey RF, Mavale-Manuel S, Meltzer EO, Mohammad Y, Mullol J, Naclerio R, O'Hehir RE, Ohta K, Ouedraogo S, Palkonen S, Papadopoulos N, Passalacqua G, Pawankar R, Popov TA, Rabe KF, Rosado-Pinto J, Scadding GK, Simons FER, Toskala E, Valovirta E, van Cauwenberge P, Wang DY, Wickman M, Yawn BP, Yorgancioglu A, Yusuf OM, Zar H, Annesi-Maesano I, Bateman ED, Ben Kheder A, Boakye DA, Bouchard J, Burney P, Busse WW, Chan-Yeung M, Chavannes NH, Chuchalin A, Dolen WK, Emuzyte R, Grouse L, Humbert M, Jackson C, Johnston SL, Keith PK, Kemp JP, Klossek JM, Larenas-Linnemann D, Lipworth B, Malo JL, Marshall GD, Naspitz C, Nekam K, Niggemann B, Nizankowska-Mogilnicka E, Okamoto Y, Orru MP, Potter P, Price D, Stoloff SW, Vandenplas O, Viegi G, Williams D. Allergic Rhinitis and its Impact on Asthma (ARIA) 2008 update (in collaboration with the World Health Organization, GA(2)LEN and AllerGen). Allergy 2008; 63 Suppl 86:8-160. [PMID: 18331513 DOI: 10.1111/j.1398-9995.2007.01620.x] [Citation(s) in RCA: 3049] [Impact Index Per Article: 190.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
MESH Headings
- Adolescent
- Asthma/epidemiology
- Asthma/etiology
- Asthma/therapy
- Child
- Global Health
- Humans
- Prevalence
- Rhinitis, Allergic, Perennial/complications
- Rhinitis, Allergic, Perennial/diagnosis
- Rhinitis, Allergic, Perennial/epidemiology
- Rhinitis, Allergic, Perennial/therapy
- Rhinitis, Allergic, Seasonal/complications
- Rhinitis, Allergic, Seasonal/diagnosis
- Rhinitis, Allergic, Seasonal/epidemiology
- Rhinitis, Allergic, Seasonal/therapy
- Risk Factors
- World Health Organization
Collapse
Affiliation(s)
- J Bousquet
- University Hospital and INSERM, Hôpital Arnaud de Villeneuve, Montpellier, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Struve MF, Wong VA, Marshall MW, Kimbell JS, Schroeter JD, Dorman DC. Nasal uptake of inhaled acrolein in rats. Inhal Toxicol 2008; 20:217-25. [PMID: 18300044 DOI: 10.1080/08958370701864219] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
An improved understanding of the relationship between inspired concentration of the potent nasal toxicant acrolein and delivered dose is needed to support quantitative risk assessments. The uptake efficiency (UE) of 0.6, 1.8, or 3.6 ppm acrolein was measured in the isolated upper respiratory tract (URT) of anesthetized naive rats under constant-velocity unidirectional inspiratory flow rates of 100 or 300 ml/min for up to 80 min. An additional group of animals was exposed to 0.6 or 1.8 ppm acrolein, 6 h/day, 5 days/wk, for 14 days prior to performing nasal uptake studies (with 1.8 or 3.6 ppm acrolein) at a 100 ml/min airflow rate. Olfactory and respiratory glutathione (GSH) concentrations were also evaluated in naive and acrolein-preexposed rats. Acrolein UE in naive animals was dependent on the concentration of inspired acrolein, airflow rate, and duration of exposure, with increased UE occurring with lower acrolein exposure concentrations. A statistically significant decline in UE occurred during the exposures. Exposure to acrolein vapor resulted in reduced respiratory epithelial GSH concentrations. In acrolein-preexposed animals, URT acrolein UE was also dependent on the acrolein concentration used prior to the uptake exposure, with preexposed rats having higher UE than their naive counterparts. Despite having increased acrolein UE, GSH concentrations in the respiratory epithelium of acrolein preexposed rats were higher at the end of the 80 min acrolein uptake experiment than their in naive rat counterparts, suggesting that an adaptive response in GSH metabolism occurred following acrolein preexposure.
Collapse
Affiliation(s)
- Melanie F Struve
- CIIT at The Hamner Institutes for Health Sciences, Research Triangle Park, North Carolina, USA
| | | | | | | | | | | |
Collapse
|
25
|
Schroeter JD, Kimbell JS, Gross EA, Willson GA, Dorman DC, Tan YM, Clewell HJ. Application of physiological computational fluid dynamics models to predict interspecies nasal dosimetry of inhaled acrolein. Inhal Toxicol 2008; 20:227-43. [PMID: 18300045 DOI: 10.1080/08958370701864235] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Acrolein is a highly soluble and reactive aldehyde and is a potent upper-respiratory-tract irritant. Acrolein-induced nasal lesions in rodents include olfactory epithelial atrophy and inflammation, epithelial hyperplasia, and squamous metaplasia of the respiratory epithelium. Nasal uptake of inhaled acrolein in rats is moderate to high, and depends on inspiratory flow rate, exposure duration, and concentration. In this study, anatomically accurate three-dimensional computational fluid dynamics (CFD) models were used to simulate steady-state inspiratory airflow and to quantitatively predict acrolein tissue dose in rat and human nasal passages. A multilayered epithelial structure was included in the CFD models to incorporate clearance of inhaled acrolein by diffusion, blood flow, and first-order and saturable metabolic pathways. Kinetic parameters for these pathways were initially estimated by fitting a pharmacokinetic model with a similar epithelial structure to time-averaged acrolein nasal extraction data and were then further adjusted using the CFD model. Predicted air:tissue flux from the rat nasal CFD model compared well with the distribution of acrolein-induced nasal lesions from a subchronic acrolein inhalation study. These correlations were used to estimate a tissue dose-based no-observed-adverse-effect level (NOAEL) for inhaled acrolein. A human nasal CFD model was used to extrapolate effects in laboratory animals to human exposure conditions on the basis of localized tissue dose and tissue responses. Assuming that equivalent tissue dose will induce similar effects across species, a NOAEL human equivalent concentration for inhaled acrolein was estimated to be 8 ppb.
Collapse
Affiliation(s)
- Jeffry D Schroeter
- The Hamner Institutes for Health Sciences, Research Triangle Park, North Carolina 27709-2137, USA.
| | | | | | | | | | | | | |
Collapse
|
26
|
Abstract
The transient receptor potential (TRP) channels are a large family of proteins with six main subfamilies termed the TRPC (canonical), TRPV (vanilloid), TRPM (melastatin), TRPP (polycystin), TRPML (mucolipin), and TRPA (ankyrin) groups. The sheer number of different TRPs with distinct functions supports the statement that these channels are involved in a wide range of processes ranging from sensing of thermal and chemical signals to reloading intracellular stores after responding to an extracellular stimulus. Mutations in TRPs are linked to pathophysiology and specific diseases. An understanding of the role of TRPs in normal physiology is just beginning; the progression from mutations in TRPs to pathophysiology and disease will follow. In this review, we focus on two distinct aspects of TRP channel physiology, the role of TRP channels in intracellular Ca2+ homeostasis, and their role in the transduction of painful stimuli in sensory neurons.
Collapse
Affiliation(s)
- S E Jordt
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520-8066, USA
| | | |
Collapse
|
27
|
Hazari MS, Rowan WH, Winsett DW, Ledbetter AD, Haykal-Coates N, Watkinson WP, Costa DL. Potentiation of pulmonary reflex response to capsaicin 24h following whole-body acrolein exposure is mediated by TRPV1. Respir Physiol Neurobiol 2007; 160:160-71. [PMID: 17950047 DOI: 10.1016/j.resp.2007.09.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 09/06/2007] [Accepted: 09/11/2007] [Indexed: 11/26/2022]
Abstract
Pulmonary C-fibers are stimulated by irritant air pollutants producing apnea, bronchospasm, and decrease in HR. Chemoreflex responses resulting from C-fiber activation are sometimes mediated by TRPV1 and release of substance P. While acrolein has been shown to stimulate C-fibers, the persistence of acrolein effects and the role of C-fibers in these responses are unknown. These experiments were designed to determine the effects of whole-body acrolein exposure and pulmonary chemoreflex response post-acrolein. Rats were exposed to either air or 3 ppm acrolein for 3 h while ventilatory function and HR were measured; 1-day later response to capsaicin challenge was measured in anesthetized rats. Rats experienced apnea and decrease in HR upon exposure to acrolein, which was not affected by either TRPV1 antagonist or NK(1)R antagonist pretreatment. Twenty-four hours later, capsaicin caused apnea and bronchoconstriction in control rats, which was potentiated in rats exposed to acrolein. Pretreatment with TRPV1 antagonist or NK(1)R antagonist prevented potentiation of apneic response and bronchoconstriction 24h post-exposure. These data suggest that although potentiation of pulmonary chemoreflex response 24h post-acrolein is mediated by TRPV1 and release of substance P, cardiopulmonary inhibition during whole-body acrolein exposure is mediated through other mechanisms.
Collapse
Affiliation(s)
- Mehdi S Hazari
- Curriculum in Toxicology, University of North Carolina, Chapel Hill, NC 27599-7270, United States.
| | | | | | | | | | | | | |
Collapse
|
28
|
Pauluhn J, Vohr HW. Partial C-fiber ablation modulates diphenylmethane-4,4′-diisocyanate (MDI)-induced respiratory allergy in Brown Norway rats. Toxicology 2006; 228:188-99. [DOI: 10.1016/j.tox.2006.08.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2006] [Revised: 08/21/2006] [Accepted: 08/22/2006] [Indexed: 10/24/2022]
|
29
|
Bautista DM, Jordt SE, Nikai T, Tsuruda PR, Read AJ, Poblete J, Yamoah EN, Basbaum AI, Julius D. TRPA1 mediates the inflammatory actions of environmental irritants and proalgesic agents. Cell 2006; 124:1269-82. [PMID: 16564016 DOI: 10.1016/j.cell.2006.02.023] [Citation(s) in RCA: 1425] [Impact Index Per Article: 79.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2005] [Revised: 01/06/2006] [Accepted: 02/08/2006] [Indexed: 12/20/2022]
Abstract
TRPA1 is an excitatory ion channel targeted by pungent irritants from mustard and garlic. TRPA1 has been proposed to function in diverse sensory processes, including thermal (cold) nociception, hearing, and inflammatory pain. Using TRPA1-deficient mice, we now show that this channel is the sole target through which mustard oil and garlic activate primary afferent nociceptors to produce inflammatory pain. TRPA1 is also targeted by environmental irritants, such as acrolein, that account for toxic and inflammatory actions of tear gas, vehicle exhaust, and metabolic byproducts of chemotherapeutic agents. TRPA1-deficient mice display normal cold sensitivity and unimpaired auditory function, suggesting that this channel is not required for the initial detection of noxious cold or sound. However, TRPA1-deficient mice exhibit pronounced deficits in bradykinin-evoked nociceptor excitation and pain hypersensitivity. Thus, TRPA1 is an important component of the transduction machinery through which environmental irritants and endogenous proalgesic agents depolarize nociceptors to elicit inflammatory pain.
Collapse
Affiliation(s)
- Diana M Bautista
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94143, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Inoue T, Bryant BP. Multiple types of sensory neurons respond to irritating volatile organic compounds (VOCs): Calcium fluorimetry of trigeminal ganglion neurons. Pain 2005; 117:193-203. [PMID: 16043294 DOI: 10.1016/j.pain.2005.06.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2004] [Revised: 06/09/2005] [Accepted: 06/13/2005] [Indexed: 02/06/2023]
Abstract
Many volatile organic compounds (VOCs) are significant environmental irritants that stimulate somatosensory nerve endings to produce pain and irritation. We measured intracellular calcium in cultured trigeminal ganglion neurons to characterize the cellular mechanisms and chemical structural determinants underlying sensitivity to VOCs. Trigeminal neurons responded to homologous series of alcohols (C4-C7) as well as saturated and unsaturated aldehydes in a concentration dependent manner. Ranked in terms of threshold to recruit neurons by compounds of the same carbon chain length, enaldehyde<aldehyde<alcohol. Unlike aldehydes and alcohols that displayed ascending concentration curves, recruitment of neurons by enaldehydes (C4-C7) appeared to saturate, consistent with a mechanism that is restricted in its neural distribution. Using pentanol, pentanal and pentenal as model compounds, we found that many but not all cool/cold-sensitive and capsaicin-sensitive neurons responded with increases in intracellular calcium. These VOCs also stimulated other neurons that were insensitive to cooling and capsaicin. Because not all cooling- and all capsaicin-sensitive neurons responded to the model VOCs, it is highly unlikely that known nociceptive ion channels such as TRPV1 or TRPA1 mediate sensitivity to these compounds. For pentanol, pentanal and pentenal, induced calcium influx was dependent on the presence of extracellular calcium. Responses of all neurons to pentanal and pentenal were also dependent upon extracellular sodium. Responses to pentanol were variably dependent on sodium. The distribution of sensitivity suggests that VOC irritation may be mediated by an as yet unidentified mechanism(s) that is/are distributed across different modalities of neurons.
Collapse
Affiliation(s)
- Takashi Inoue
- Monell Chemical Senses Center, 3500 Market Street, Philadelphia, PA 19104, USA
| | | |
Collapse
|
31
|
van Thriel C, Wiesmüller GA, Blaszkewicz M, Golka K, Kiesswetter E, Seeber A, Bachert C. Intranasal effects in chemically sensitive volunteers: an experimental exposure study. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2003; 14:129-137. [PMID: 21782672 DOI: 10.1016/s1382-6689(03)00047-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2003] [Accepted: 07/09/2003] [Indexed: 05/31/2023]
Abstract
During inhalational exposure to irritants stimulation of the trigeminal nerve endings in the nasal mucosa or other biochemical mechanisms might initiate inflammatory processes. Increased sensitivity of this physiological system in response to chemical stimulation is postulated in subjects reporting chemical intolerance. In the present study 12 subjects reporting chemical sensitivity and 12 controls were exposed to different concentrations of the industrial solvents ethyl benzene and methyl ethyl ketone (MEK). Concentrations of various inflammatory biomarkers, namely eosinophil cationic protein (ECP), myeloperoxidase (MPO), interleukin 1β (IL-lβ), substance P (SP), and neurokinin A (NKA) were measured in nasal secretion after exposures. Before, during, and after the exposures subjects rated the severity of nasal irritations. The biomarker concentrations and reported irritations were not affected by the exposures. Regardless of substance and concentration sensitive subjects reported more nasal irritations. In conclusion, the investigated substances might possess weaker potency to elicit intranasal irritative effects than postulated.
Collapse
Affiliation(s)
- Christoph van Thriel
- Leibniz Research Centre for Working Environment and Human Factors, Institut für Arbeitsphysiologie an der Universität Dortmund, Ardeystrasse 67, D-44139 Dortmund, Germany
| | | | | | | | | | | | | |
Collapse
|
32
|
Morris JB, Symanowicz PT, Olsen JE, Thrall RS, Cloutier MM, Hubbard AK. Immediate sensory nerve-mediated respiratory responses to irritants in healthy and allergic airway-diseased mice. J Appl Physiol (1985) 2003; 94:1563-71. [PMID: 12626476 DOI: 10.1152/japplphysiol.00572.2002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The immediate responses of the upper respiratory tract (URT) to the irritants acrolein and acetic acid were examined in healthy and allergic airway-diseased C57Bl/6J mice. Acrolein (1.1 ppm) and acetic acid (330 ppm) vapors induced an immediate increase in flow resistance, as measured in the surgically isolated URT of urethane-anesthetized healthy animals. Acrolein, but not acetic acid, induced a small URT vasodilatory response. In awake spontaneously breathing mice, both vapors induced a prolonged pause at the start of expiration (a response mediated via stimulation of nasal trigeminal nerves) and an increase in total respiratory specific airway flow resistance, the magnitude of which was similar to that observed in the isolated URT. Both responses were significantly reduced in animals pretreated with large doses of capsaicin to defunctionalize sensory nerves, strongly suggesting a role for sensory nerves in development of these responses. The breathing pattern and/or obstructive responses were enhanced in mice with ovalbumin-induced allergic airway disease. These results suggest that the primary responses to acrolein and acetic acid vapors are altered breathing patterns and airway obstruction, that sensory nerves play an important role in these responses, and that these responses are enhanced in animals with allergic airway disease.
Collapse
Affiliation(s)
- John B Morris
- University of Connecticut Pulmonary Research Consortium, Department of Pharmaceutical Sciences, Storrs, Connecticut 06269, USA.
| | | | | | | | | | | |
Collapse
|
33
|
Ho CY, Kou YR. Mechanisms of wood smoke-induced increases in nasal airway resistance and reactivity in rats. Eur J Pharmacol 2002; 436:127-34. [PMID: 11834256 DOI: 10.1016/s0014-2999(01)01608-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We investigated the mechanisms of wood smoke-induced increases in nasal airway resistance (RNA) and airway reactivity in anesthetized rats. Delivery of wood smoke into a functionally isolated nasal airway produced an increase in RNA, which was attenuated by CP-96,345 [a tachykinin NK(1) receptor antagonist; (2S,3S)-cis-2-(diphenylmethyl)-N-((2-methoxyphenyl)-methyl)-1-azabicyclo(2.2.2.)-octan-3-amine] or atropine. Additionally, smoke pre-exposure animals displayed a greater amplitude and a longer duration of RNA responses to capsaicin or histamine provocation, as compared to air controls. This enhanced airway reactivity to capsaicin or histamine was largely alleviated by CP-96,345 or atropine. The nasal secretory responses to capsaicin or histamine in smoke pre-exposure animals were similar to those in air controls. We concluded that (1) reflex cholinergic and tachykininergic mechanisms play important roles in wood smoke-induced increases in nasal airway resistance and airway reactivity, and (2) this nasal airway hyperreactivity might not be due to an exaggerated secretory response, but is presumably due to augmented nasal swelling.
Collapse
Affiliation(s)
- Ching Yin Ho
- Institute of Physiology, School of Medicine and Life Science, National Yang-Ming University, Shih-Pai, 11221, Taipei, Taiwan
| | | |
Collapse
|
34
|
Morris JB, Symanowicz P, Sarangapani R. Regional distribution and kinetics of vinyl acetate hydrolysis in the oral cavity of the rat and mouse. Toxicol Lett 2002; 126:31-9. [PMID: 11738268 DOI: 10.1016/s0378-4274(01)00442-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Vinyl acetate is an ester that is used to make polyvinyl acetate based polymers that are used in the manufacture of latex paints and adhesives. Chronic oral exposure to high concentrations of vinyl acetate induces oral tumors in rodents. Since carboxylesterase-dependent hydrolysis of VA to acetic acid and acetaldehyde has been implicated in the nasal inhalation carcinogenesis of this ester, the potential for oral mucosa of the F344 rat and BDF mouse to hydrolyze VA was examined. Homogenates were prepared by scraping the mucosa from four regions of the oral cavity: dorsal interior (all tissues interior to the teeth), dorsal tongue surface, ventral interior (sublingual area and lower interior tissues) and exterior (all tissues exterior to the teeth). The oral cavity was rinsed once with saline prior to dissection to determine if oral secretions possessed metabolic capacity. Aliquots of the homogenates or rinse fluid were incubated for 30 min with varying concentrations of vinyl acetate (0.05-10 mM), and the production of acetaldehyde was quantitated by HPLC. All tissue regions possessed VA hydrolysis activity. In both species the hydrolysis activity was greatest in the dorsal interior region (Vmax of 90 and 6 nmol/min in the rat and mouse, respectively, Km values of 0.5 and 0.9 mM). Activity in the other oral regions was 2-15-fold lower. Activity was observed in the rinse fluid, but was 20-fold or more lower than the dorsal interior region. Finally, solutions of vinyl acetate were placed in the mouth of anesthetized rats for 10 min and then analyzed for acetaldehyde concentrations. Acetaldehyde was detected in these solutions providing evidence that metabolism of this ester occurs in vivo in oral tissues.
Collapse
Affiliation(s)
- John B Morris
- Toxicology Program, Department of Pharmaceutical Sciences, University of Connecticut, Box U-2092, Storrs, CT 06269, USA.
| | | | | |
Collapse
|
35
|
Bousquet J, Van Cauwenberge P, Khaltaev N. Allergic rhinitis and its impact on asthma. J Allergy Clin Immunol 2001; 108:S147-334. [PMID: 11707753 DOI: 10.1067/mai.2001.118891] [Citation(s) in RCA: 2094] [Impact Index Per Article: 91.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- J Bousquet
- Department of Allergy and Respiratory Diseases, University Hospital and INSERM, Montpellier, France
| | | | | |
Collapse
|
36
|
Stanek J, Symanowicz PT, Olsen JE, Gianutsos G, Morris JB. Sensory-nerve-mediated nasal vasodilatory response to inspired acetaldehyde and acetic acid vapors. Inhal Toxicol 2001; 13:807-22. [PMID: 11498807 DOI: 10.1080/08958370120057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This study was designed to characterize the acute nasal vasodilatory responses to the sensory irritants acetaldehyde and acetic acid. For this purpose, the upper respiratory tract of the urethane-anesthetized male F344 rat was isolated by insertion of an endotracheal cannula, and irritant-laden air was drawn continuously through that site at a flow rate of 100 ml/min for 50 min. Vascular function was monitored by measuring inert vapor (acetone) uptake throughout the exposure. Both acetaldehyde and acetic acid induced an immediate concentration-dependent vasodilation as indicated by increased steady-state acetone uptake rates. This response was observed at exposure concentrations of 25 ppm or 130 ppm or higher for acetaldehyde or acetic acid, respectively. The response to either vapor was significantly diminished in rats pretreated with the sensory nerve toxin capsaicin (50 mg/kg, 7 days prior to exposure), providing evidence that sensory nerves play a role in the response. Acetaldehyde is metabolized by aldehyde dehydrogenase to acetic acid. Pretreatment with the aldehyde dehydrogenase inhibitor cyanamide (10 mg/kg, 1 h prior to exposure) reduced the vasodilatory response to 200 ppm but not to 50 ppm acetaldehyde. These results suggest that formation of acetic acid is important in the sensory nerve-mediated vasodilatory response to high, but perhaps not to low, concentrations of acetaldehyde.
Collapse
Affiliation(s)
- J Stanek
- Toxicology Program, Box U-92, Department of Pharmaceutical Sciences, University of Connecticut, Storrs, CT 06269-2092, USA
| | | | | | | | | |
Collapse
|
37
|
Feron VJ, Arts JH, Kuper CF, Slootweg PJ, Woutersen RA. Health risks associated with inhaled nasal toxicants. Crit Rev Toxicol 2001; 31:313-47. [PMID: 11405443 DOI: 10.1080/20014091111712] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Health risks of inhaled nasal toxicants were reviewed with emphasis on chemically induced nasal lesions in humans, sensory irritation, olfactory and trigeminal nerve toxicity, nasal immunopathology and carcinogenesis, nasal responses to chemical mixtures, in vitro models, and nasal dosimetry- and metabolism-based extrapolation of nasal data in animals to humans. Conspicuous findings in humans are the effects of outdoor air pollution on the nasal mucosa, and tobacco smoking as a risk factor for sinonasal squamous cell carcinoma. Objective methods in humans to discriminate between sensory irritation and olfactory stimulation and between adaptation and habituation have been introduced successfully, providing more relevant information than sensory irritation studies in animals. Against the background of chemoperception as a dominant window of the brain on the outside world, nasal neurotoxicology is rapidly developing, focusing on olfactory and trigeminal nerve toxicity. Better insight in the processes underlying neurogenic inflammation may increase our knowledge of the causes of the various chemical sensitivity syndromes. Nasal immunotoxicology is extremely complex, which is mainly due to the pivotal role of nasal lymphoid tissue in the defense of the middle ear, eye, and oral cavity against antigenic substances, and the important function of the nasal passages in brain drainage in rats. The crucial role of tissue damage and reactive epithelial hyperproliferation in nasal carcinogenesis has become overwhelmingly clear as demonstrated by the recently developed biologically based model for predicting formaldehyde nasal cancer risk in humans. The evidence of carcinogenicity of inhaled complex mixtures in experimental animals is very limited, while there is ample evidence that occupational exposure to mixtures such as wood, leather, or textile dust or chromium- and nickel-containing materials is associated with increased risk of nasal cancer. It is remarkable that these mixtures are aerosols, suggesting that their "particulate nature" may be a major factor in their potential to induce nasal cancer. Studies in rats have been conducted with defined mixtures of nasal irritants such as aldehydes, using a model for competitive agonism to predict the outcome of such mixed exposures. When exposure levels in a mixture of nasal cytotoxicants were equal to or below the "No-Observed-Adverse-Effect-Levels" (NOAELs) of the individual chemicals, neither additivity nor potentiation was found, indicating that the NOAEL of the "most risky chemical" in the mixture would also be the NOAEL of the mixture. In vitro models are increasingly being used to study mechanisms of nasal toxicity. However, considering the complexity of the nasal cavity and the many factors that contribute to nasal toxicity, it is unlikely that in vitro experiments ever will be substitutes for in vivo inhalation studies. It is widely recognized that a strategic approach should be available for the interpretation of nasal effects in experimental animals with regard to potential human health risk. Mapping of nasal lesions combined with airflow-driven dosimetry and knowledge about local metabolism is a solid basis for extrapolation of animal data to humans. However, more research is needed to better understand factors that determine the susceptibility of human and animal tissues to nasal toxicants, in particular nasal carcinogens.
Collapse
Affiliation(s)
- V J Feron
- Toxicology Division, TNO Nutrition and Food Research, Zeist, The Netherlands.
| | | | | | | | | |
Collapse
|
38
|
Abstract
This review is aimed at highlighting toxicologically relevant physiological and biochemical factors that influence the delivery of inhaled vapors to nasal tissues. Numerous experiments in rodents have shown that vapor uptake efficiencies are dependent on vapor solubility (as measured by blood:air partition coefficient) and inspiratory flow rate. Nasal tissues are rich in xenobiotic metabolizing enzymes, and it has been shown experimentally through the use of metabolic inhibitors that inspired vapors are metabolized in nasal tissue and that this process serves to enhance inspired vapor uptake efficiency in that site. Metabolism-based species differences in vapor uptake have been observed among rodent species. Concentration-dependent changes in vapor uptake have also been observed and related to saturation of local metabolic pathways at high exposure concentrations. Therefore, appropriate consideration of local metabolism is necessary for comprehensive high- to low-dose or species extrapolations of nasal toxicity data. Recent studies have provided evidence of sensory nerve-mediated reflex responses that alter nasal vascular function and may alter nasal inspired vapor dosimetric relationships. In toto, these studies also indicate the need to define uptake behavior for a vapor of interest over a wide range of exposure concentrations due to the possibility of nonlinear metabolism kinetics or the induction of nasal reflex and/or toxic responses. Such data are required for the formulation of a robust nasal dosimetry model.
Collapse
Affiliation(s)
- J B Morris
- Toxicology Program, Department of Pharmaceutical Sciences, Box U-92, University of Connecticut, Storrs, CT 06269-2092, USA.
| |
Collapse
|