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Home / Equine Research Bank / PLoS One / Nebulization of 2% lidocaine has no detectable impact on the...
PloS one2025; 20(1); e0316079; doi: 10.1371/journal.pone.0316079

Nebulization of 2% lidocaine has no detectable impact on the healthy equine respiratory microbiota.

Abstract: Glucocorticosteroids remain the most common pharmaceutical approach for the treatment of equine asthma but can be associated with significant side effects, including respiratory microbiome alterations. The goal of the study was to assess the impact of 2% lidocaine nebulization, a projected alternative treatment of equine asthma, on the healthy equine respiratory microbiota. A prospective, randomized, controlled, blinded, 2-way crossover study was performed, to assess the effect of 1 mg/kg 2% lidocaine (7 treatments over 4 days) on the equine respiratory microbiota compared to control horses (saline and no treatment). Clinical assessments and respiratory samples, including nasal wash, endoscopic tracheal aspirate and bronchoalveolar lavage fluid, were obtained at each sample collection timepoint. The profile of the respiratory bacterial microbiota was evaluated using 16S amplicon sequencing, and clinical data compared using related samples analyses, based on data normality. The treatment did not affect the clinical data or alter the tracheal and nasal microbiota in healthy horses. However, time explained 12.6% of microbiota variation among samples. A significant difference in bacterial composition was observed between nasal and tracheal samples, showing the greatest relative abundance of Actinobacteria and Firmicutes, respectively. Bacterial DNA from bronchoalveolar lavage fluid did not amplify with generic primers targeting the V4 variable region of the prokaryotic small subunit ribosomal RNA gene, despite attempting multiple DNA extraction methods and PCR protocols, and after excluding PCR inhibition. This observation indicates that bronchoalveolar lavage fluid of healthy horses has a low bacterial load.
Copyright: © 2025 Holley et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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Publication Date: 2025-01-24 PubMed ID: 39854381PubMed Central: PMC11759996DOI: 10.1371/journal.pone.0316079Google Scholar: Lookup
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  • Journal Article
  • Randomized Controlled Trial
  • Veterinary

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

The research investigates the effects of nebulized 2% lidocaine, a proposed alternative treatment for equine asthma, on the respiratory microbiota of healthy horses. Findings indicate that this treatment does not alter nasal or tracheal microbiota in healthy horses.

Overall Research Design and Objectives

  • The research seeks to assess the impact of nebulized 2% lidocaine, an alternative treatment for equine asthma, on the respiratory microbiota of healthy horses. The study was conceived due to side effects associated with the common approach to treating equine asthma, glucocorticosteroids, which can alter the respiratory microbiome.

Experimental Methodology

  • A prospective, randomized, controlled, blinded, 2-way crossover study was executed. The study compared the effects of 1 mg/kg 2% lidocaine (delivered in 7 treatments over a period of 4 days) on equine respiratory microbiota with control horses receiving saline and no treatment.
  • Respiratory samples including nasal wash, endoscopic tracheal aspirate, and bronchoalveolar lavage fluid were taken at each stage for investigation.
  • The research utilized 16S amplicon sequencing to evaluate the profile of the equine respiratory bacterial microbiota. Comparison of the clinical data was done using related sample analyses based on data normality.

Resultant Findings

  • Results revealed that the 2% lidocaine nebulization had no effect on clinical data, nor did it alter the nasal or tracheal microbiota in the healthy horses subjected to the treatment.
  • Time was found to explain 12.6% of the microbiota variation among samples, signifying a role for temporal changes in microbiota dynamics.
  • A significant difference in bacterial composition was noted between nasal and tracheal samples, with Actinobacteria and Firmicutes having the greatest relative abundance in these locations, respectively.
  • Despite numerous attempts with multiple DNA extraction methods and PCR protocols, and even after excluding PCR inhibition, bacterial DNA was not successfully amplified from the bronchoalveolar lavage fluid. This indicates that the bronchoalveolar lavage fluid of healthy horses carries a low bacterial load.

Cite This Article

APA
Holley L, Creasey HN, Bedenice D, Reed S, Romualdo da Silva DR, Trautwein V, Mazan M, Widmer G. (2025). Nebulization of 2% lidocaine has no detectable impact on the healthy equine respiratory microbiota. PLoS One, 20(1), e0316079. https://doi.org/10.1371/journal.pone.0316079

Publication

PloS one
ISSN: 1932-6203
NlmUniqueID: 101285081
Country: United States
Language: English
Volume: 20
Issue: 1
Pages: e0316079

Researcher Affiliations

Holley, Lauren
  • Cummings School of Veterinary Medicine at Tufts University, Department of Clinical Sciences, North Grafton, MA, United States of America.
Creasey, Hannah N
  • Cummings School of Veterinary Medicine at Tufts University, Department of Infectious Diseases and Global Health, North Grafton, MA, United States of America.
Bedenice, Daniela
  • Cummings School of Veterinary Medicine at Tufts University, Department of Clinical Sciences, North Grafton, MA, United States of America.
Reed, Sarah
  • University of Connecticut, Department of Animal Science, Storrs, CT, United States of America.
Romualdo da Silva, Debora Regina
  • Cummings School of Veterinary Medicine at Tufts University, Department of Infectious Diseases and Global Health, North Grafton, MA, United States of America.
  • São Paulo State University (UNESP), School of Veterinary Medicine, Araçatuba, São Paulo, Brazil.
Trautwein, Victoria
  • Cummings School of Veterinary Medicine at Tufts University, Department of Clinical Sciences, North Grafton, MA, United States of America.
Mazan, Melissa
  • Cummings School of Veterinary Medicine at Tufts University, Department of Clinical Sciences, North Grafton, MA, United States of America.
Widmer, Giovanni
  • Cummings School of Veterinary Medicine at Tufts University, Department of Infectious Diseases and Global Health, North Grafton, MA, United States of America.

MeSH Terms

  • Animals
  • Bacteria / genetics
  • Bronchoalveolar Lavage Fluid / microbiology
  • Cross-Over Studies
  • Horses / microbiology
  • Lidocaine / administration & dosage
  • Lidocaine / pharmacology
  • Microbiota / drug effects
  • Nebulizers and Vaporizers
  • Prospective Studies
  • RNA, Ribosomal, 16S / genetics
  • Trachea / microbiology

Grant Funding

  • R21 AI144521 / NIAID NIH HHS
  • R21 DK132314 / NIDDK NIH HHS

Conflict of Interest Statement

The authors have declared that no competing interests exist.

References

This article includes 49 references
  1. Faner R, Sibila O, Agustí A, Bernasconi E, Chalmers JD, Huffnagle GB. The microbiome in respiratory medicine: current challenges and future perspectives.. European Respiratory Journal 2017;49(4).
    doi: 10.1183/13993003.02086-2016pubmed: 28404649google scholar: lookup
  2. Dickson RP, Erb-Downward JR, Huffnagle GB. The role of the bacterial microbiome in lung disease.. Expert review of respiratory medicine 2013;7(3):245–57.
    doi: 10.1586/ers.13.24pmc: PMC4007100pubmed: 23734647google scholar: lookup
  3. Yang X, Jiang Y, Wang C. Does IL-17 respond to the disordered lung microbiome and contribute to the neutrophilic phenotype in asthma?. Mediators of inflammation 2016;2016.
    pmc: PMC4749797pubmed: 26941484
  4. Loverdos K, Bellos G, Kokolatou L, Vasileiadis I, Giamarellos E, Pecchiari M. Lung microbiome in asthma: current perspectives.. Journal of Clinical Medicine 2019;8(11):1967.
    doi: 10.3390/jcm8111967pmc: PMC6912699pubmed: 31739446google scholar: lookup
  5. Huang YJ, Nelson CE, Brodie EL, DeSantis TZ, Baek MS, Liu J. Airway microbiota and bronchial hyperresponsiveness in patients with suboptimally controlled asthma.. Journal of Allergy and Clinical Immunology 2011;127(2):372–81. e3.
    doi: 10.1016/j.jaci.2010.10.048pmc: PMC3037020pubmed: 21194740google scholar: lookup
  6. Bond SL, Timsit E, Workentine M, Alexander T, Léguillette R. Upper and lower respiratory tract microbiota in horses: bacterial communities associated with health and mild asthma (inflammatory airway disease) and effects of dexamethasone.. BMC microbiology 2017;17(1):1–11.
    pmc: PMC5569571pubmed: 28835202
  7. Fillion-Bertrand G, Dickson RP, Boivin R, Lavoie J-P, Huffnagle GB, Leclere M. Lung microbiome is influenced by the environment and asthmatic status in an equine model of asthma.. American journal of respiratory cell and molecular biology 2019;60(2):189–97.
    doi: 10.1165/rcmb.2017-0228OCpubmed: 30183323google scholar: lookup
  8. Mitchell AB, Glanville AR. The human respiratory microbiome: implications and impact.. Seminars in Respiratory and Critical Care Medicine 2018.
    pubmed: 29579771
  9. Couetil L, Cardwell JM, Leguillette R, Mazan M, Richard E, Bienzle D. Equine Asthma: Current Understanding and Future Directions.. Frontiers in veterinary science 2020;7:450–.
    doi: 10.3389/fvets.2020.00450pmc: PMC7438831pubmed: 32903600google scholar: lookup
  10. Bond SL, Workentine M, Hundt J, Gilkerson JR, Léguillette R. Effects of nebulized dexamethasone on the respiratory microbiota and mycobiota and relative equine herpesvirus‐1, 2, 4, 5 in an equine model of asthma.. Journal of veterinary internal medicine 2020;34(1):307–21.
    doi: 10.1111/jvim.15671pmc: PMC6979091pubmed: 31793692google scholar: lookup
  11. Denner DR, Sangwan N, Becker JB, Hogarth DK, Oldham J, Castillo J. Corticosteroid therapy and airflow obstruction influence the bronchial microbiome, which is distinct from that of bronchoalveolar lavage in asthmatic airways.. Journal of Allergy and Clinical Immunology 2016;137(5):1398–405. e3.
    doi: 10.1016/j.jaci.2015.10.017pmc: PMC4860110pubmed: 26627545google scholar: lookup
  12. Sokolowska M, Frei R, Lunjani N, Akdis CA, O’Mahony L. Microbiome and asthma.. Asthma research and practice 2018;4(1):1–9.
    doi: 10.1186/s40733-017-0037-ypmc: PMC5755449pubmed: 29318023google scholar: lookup
  13. Al Bataineh MT, Hamoudi RA, Dash NR, Ramakrishnan RK, Almasalmeh MA, Sharif HA. Altered respiratory microbiota composition and functionality associated with asthma early in life.. BMC infectious diseases 2020;20(1):1–11.
    doi: 10.1186/s12879-020-05427-3pmc: PMC7510324pubmed: 32962658google scholar: lookup
  14. Mahalingam-Dhingra A, Mazan MR, Bedenice D, Ceresia M, Minuto J, Deveney EF. A CONSORT-guided, randomized, double-blind, controlled pilot clinical trial of inhaled lidocaine for the treatment of equine asthma.. Canadian journal of veterinary research 2022;86(2):116–24.
    pmc: PMC8978287pubmed: 35388235
  15. Minuto JS, Mazan M, Bedenice D, M C. Lung Deposition and Systemic Absorption of Nebulized Lidocaine in Healthy Horses.. Unpublished Data. 2022.
  16. Wilson M, Berney C, Behan A, Robinson N. The effect of intravenous lidocaine infusion on bronchoalveolar lavage cytology in equine recurrent airway obstruction.. Journal of Veterinary Internal Medicine 2012;26(6):1427–32.
    doi: 10.1111/j.1939-1676.2012.01010.xpubmed: 23113678google scholar: lookup
  17. Chong C, Chen C, Ma H, Wu Y, Chen Y, Wang T. Comparison of lidocaine and bronchodilator inhalation treatments for cough suppression in patients with chronic obstructive pulmonary disease.. Emergency Medicine Journal 2005;22(6):429–32.
    doi: 10.1136/emj.2004.015719pmc: PMC1726806pubmed: 15911951google scholar: lookup
  18. Hunt LW, Frigas E, Butterfield JH, Kita H, Blomgren J, Dunnette SL. Treatment of asthma with nebulized lidocaine: a randomized, placebo-controlled study.. Journal of allergy and clinical immunology 2004;113(5):853–9.
    doi: 10.1016/j.jaci.2004.02.039pubmed: 15131566google scholar: lookup
  19. Commerce UDo. National Weather Service: United States Government; 2024 [cited 2024]. Available from: https://www.weather.gov/wrh/climate.
  20. Kozich JJ, Westcott SL, Baxter NT, Highlander SK, Schloss PD. Development of a dual-index sequencing strategy and curation pipeline for analyzing amplicon sequence data on the MiSeq Illumina sequencing platform.. Appl Environ Microbiol 2013;79(17):5112–20. Epub 2013/06/25.
    doi: 10.1128/AEM.01043-13pmc: PMC3753973pubmed: 23793624google scholar: lookup
  21. Wang Q, Garrity GM, Tiedje JM, Cole JR. Naive Bayesian classifier for rapid assignment of rRNA sequences into the new bacterial taxonomy.. Appl Environ Microbiol 2007;73(16):5261–7. Epub 2007/06/26.
    doi: 10.1128/AEM.00062-07pmc: PMC1950982pubmed: 17586664google scholar: lookup
  22. Braak Ct, Šmilauer P. CANOCO reference manual and CanoDraw for Windows user’s guide: software for canonical community ordination (version 4.5).. Microcomputer Power, Ithaca, New York. 2002.
  23. Sung H, Yong D, Ki C-S, Kim J-S, Seong M-W, Lee H. Comparative evaluation of three homogenization methods for isolating Middle East respiratory syndrome coronavirus nucleic acids from sputum samples for real-time reverse transcription PCR.. Annals of laboratory medicine 2016;36(5):457.
    doi: 10.3343/alm.2016.36.5.457pmc: PMC4940489pubmed: 27374711google scholar: lookup
  24. Leitao Filho FS, Takiguchi H, Akata K, Ra SW, Moon J-Y, Kim HK. Effects of inhaled corticosteroid/long-acting β2-agonist combination on the airway microbiome of patients with chronic obstructive pulmonary disease: a randomized controlled clinical trial (DISARM).. American journal of respiratory and critical care medicine 2021;204(10):1143–52.
    pubmed: 34464242
  25. Baker GC, Smith JJ, Cowan DA. Review and re-analysis of domain-specific 16S primers.. J Microbiol Methods 2003;55(3):541–55. Epub 2003/11/11.
    doi: 10.1016/j.mimet.2003.08.009pubmed: 14607398google scholar: lookup
  26. Creasey HN, Zhang W, Widmer G. Effect of caging on Cryptosporidium parvum proliferation in mice.. Microorganisms 2022;10(6):1242.
    doi: 10.3390/microorganisms10061242pmc: PMC9230662pubmed: 35744762google scholar: lookup
  27. Schloss PD, Westcott SL, Ryabin T, Hall JR, Hartmann M, Hollister EB. Introducing mothur: open-source, platform-independent, community-supported software for describing and comparing microbial communities.. Appl Environ Microbiol 2009;75(23):7537–41. Epub 2009/10/06.
    doi: 10.1128/AEM.01541-09pmc: PMC2786419pubmed: 19801464google scholar: lookup
  28. Ferrari ED, Oliveira BCM, Creasey HN, Romualdo da Silva DR, Nakamura AA, Bresciani KDS. The Impact of Physical Effort on the Gut Microbiota of Long-Distance Fliers.. Microorganisms 2023;11(7):1766.
    doi: 10.3390/microorganisms11071766pmc: PMC10386721pubmed: 37512938google scholar: lookup
  29. Westcott SL, Schloss PD. OptiClust, an Improved Method for Assigning Amplicon-Based Sequence Data to Operational Taxonomic Units.. mSphere 2017;2(2). Epub 2017/03/16.
    doi: 10.1128/mSphereDirect.00073-17pmc: PMC5343174pubmed: 28289728google scholar: lookup
  30. Lozupone C, Hamady M, Knight R. UniFrac—an online tool for comparing microbial community diversity in a phylogenetic context.. BMC Bioinformatics 2006;7:371–85. Epub 2006/08/09.
    doi: 10.1186/1471-2105-7-371pmc: PMC1564154pubmed: 16893466google scholar: lookup
  31. Clarke KR. Non-parametric Multivariate Analyses of Changes in Community Structure.. Australian Journal of Ecology 1993;18(1):117–43.
    doi: 10.1111/j.1442-9993.1993.tb00438.xgoogle scholar: lookup
  32. Quast C, Pruesse E, Yilmaz P, Gerken J, Schweer T, Yarza P. The SILVA ribosomal RNA gene database project: improved data processing and web-based tools.. Nucleic Acids Res 2013;41(Database issue):D590–6. Epub 2012/11/30.
    doi: 10.1093/nar/gks1219pmc: PMC3531112pubmed: 23193283google scholar: lookup
  33. Bond SL, Timsit E, Workentine M, Alexander T, Léguillette R. Upper and lower respiratory tract microbiota in horses: bacterial communities associated with health and mild asthma (inflammatory airway disease) and effects of dexamethasone.. Bmc Microbiology 2017;17.
    doi: 10.1186/s12866-017-1092-5pmc: PMC5569571pubmed: 28835202google scholar: lookup
  34. Segata N, Izard J, Waldron L, Gevers D, Miropolsky L, Garrett WS. Metagenomic biomarker discovery and explanation.. Genome Biol 2011;12(6):R60. Epub 2011/06/28.
    doi: 10.1186/gb-2011-12-6-r60pmc: PMC3218848pubmed: 21702898google scholar: lookup
  35. Lepš J, Šmilauer P. Multivariate analysis of ecological data using CANOCO:. Cambridge university press; 2003.
  36. Magurran AE, Henderson PA. Explaining the excess of rare species in natural species abundance distributions.. Nature 2003;422(6933):714–6.
    doi: 10.1038/nature01547pubmed: 12700760google scholar: lookup
  37. Bond SL, Workentine M, Hundt J, Gilkerson JR, Léguillette R. Effects of nebulized dexamethasone on the respiratory microbiota and mycobiota and relative equine herpesvirus-1, 2, 4, 5 in an equine model of asthma.. Journal of Veterinary Internal Medicine 2020;34(1):307–21.
    doi: 10.1111/jvim.15671pmc: PMC6979091pubmed: 31793692google scholar: lookup
  38. Huang YJ, Sethi S, Murphy T, Nariya S, Boushey HA, Lynch SV. Airway microbiome dynamics in exacerbations of chronic obstructive pulmonary disease.. Journal of clinical microbiology 2014;52(8):2813–23.
    doi: 10.1128/JCM.00035-14pmc: PMC4136157pubmed: 24850358google scholar: lookup
  39. Millares L, Monso E. The microbiome in COPD: emerging potential for microbiome-targeted interventions.. International Journal of Chronic Obstructive Pulmonary Disease 2022:1835–45.
    doi: 10.2147/COPD.S371958pmc: PMC9380728pubmed: 35983167google scholar: lookup
  40. Galiana A, Aguirre E, Rodriguez JC, Mira A, Santibañez M, Candela I. Sputum microbiota in moderate versus severe patients with COPD.. European Respiratory Journal 2014;43(6):1787–90.
    doi: 10.1183/09031936.00191513pubmed: 24311775google scholar: lookup
  41. Mazan MR, Lascola K, Bruns SJ, Hoffman AM. Use of a novel one-nostril mask-spacer device to evaluate airway hyperresponsiveness (AHR) in horses after chronic administration of albuterol.. Canadian Journal of Veterinary Research 2014;78(3):214–20.
    pmc: PMC4068413pubmed: 24982553
  42. McKenzie HC III, Murray MJ. Concentrations of gentamicin in serum and bronchial lavage fluid after once-daily aerosol administration to horses for seven days.. American journal of veterinary research 2004;65(2):173–8.
    doi: 10.2460/ajvr.2004.65.173pubmed: 14974574google scholar: lookup
  43. Clark C, Lester G, Vetro T, Rice B. Bronchoalveolar lavage in horses: effect of exercise and repeated sampling on cytology.. Australian veterinary journal 1995;72(7):249–52.
    doi: 10.1111/j.1751-0813.1995.tb03537.xpubmed: 8534227google scholar: lookup
  44. Woodrow JS, Hopster K, Palmisano M, Payette F, Kulp J, Stefanovski D. Time to resolution of airway inflammation caused by bronchoalveolar lavage in healthy horses.. Journal of Veterinary Internal Medicine 2024.
    doi: 10.1111/jvim.17169pmc: PMC11423487pubmed: 39198933google scholar: lookup
  45. Bond S, McMullen C, Timsit E, Léguillette R. Topography of the respiratory, oral, and guttural pouch bacterial and fungal microbiotas in horses.. Journal of veterinary internal medicine 2023;37(1):349–60.
    doi: 10.1111/jvim.16612pmc: PMC9889660pubmed: 36607177google scholar: lookup
  46. McMullen C, Alexander TW, Léguillette R, Workentine M, Timsit E. Topography of the respiratory tract bacterial microbiota in cattle.. Microbiome 2020;8:1–15.
    pmc: PMC7288481pubmed: 32522285
  47. Dickson RP, Erb-Downward JR, Freeman CM, McCloskey L, Falkowski NR, Huffnagle GB, Curtis JL. Bacterial topography of the healthy human lower respiratory tract.. MBio 2017;8(1).
    doi: 10.1128/mBio.02287-16pmc: PMC5312084pubmed: 28196961google scholar: lookup
  48. Racklyeft D, Raidal S, Love D. Towards an understanding of equine pleuropneumonia: factors relevant for control.. Australian Veterinary Journal 2000;78(5):334–8.
    doi: 10.1111/j.1751-0813.2000.tb11788.xpubmed: 10904819google scholar: lookup
  49. Chiocchetti R, Giancola F, Mazzoni M, Sorteni C, Romagnoli N, Pietra M. Excitatory and inhibitory enteric innervation of horse lower esophageal sphincter.. Histochemistry and cell biology 2015;143(6):625–35.
    doi: 10.1007/s00418-014-1306-ypubmed: 25578519google scholar: lookup
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