Le 2 Juin 2016, Michela Bullone, étudiante au doctorat en Sciences Vétérinaires sous la direction du Dr Jean-Pierre Lavoie et co-direction du Dr James Martin, a soutenu sa thèse intitulée :
Reversibility of airway remodeling in equine asthma. Contribuion of anti-inflammatory and brochodilatator therapies.
Cette dernière a reçu la mention « exceptionnelle » et a été recommandée pour la liste d’honneur du doyen de la Faculté des études supérieures, de même qu’au concours des meilleures thèses pour cette année. Alors toutes nos félicitations au Dr Michela Bullone.
EQUINE FOUNDATION CANADA: A PRECIOUS DONATION FOR ENDOBRONCHIAL ULTRASONOGRAPHY FOR THE DIAGNOSIS AND TREATMENT OF HORSES WITH CHRONIC AIRWAY DISEASES
Until recently, it was not possible to evaluate the remodelling of the central airways of horses in the living horse. This is now possible using endobronchial ultrasonography (EBUS) as we recently reported (Michela Bullone et. al, Plos One, 2015).
Thanks to Ms. Belliard and her foundation “Equine Foundation Canada”, we recently aquired a new probe and the accessories to evaluate the remodeling of the airways using this technic in the client-owned horses presented to the Vet school, Université de Montréal, for evaluation of IAD.
April 19, Ms. Belliard recently visite our installation and our new system of endobronchial Ultrasonography. It was a real privilege to receive her and we were proud to present the procedure!
Photo prise par Gabrielle Fillion-Bertrand, 19 Avril 2016
NEUTROPHIL EXOSOMES AND AIRWAY SMOOTH MUSCLE REMODELING
Vargas A, Roux-Dalvai F, Droit A, Lavoie JP.Neutrophil-derived Exosomes: A New Mechanism Contributing to Airway Smooth Muscle Remodeling. Am J Respir Cell Mol Biol.First published online 22 Apr 2016 as DOI: 10.1165/rcmb.2016-0033OC
Neutrophils are the most abundant leukocytes present in the human blood and the first cells recruited to the site of infection or injury. We recently demonstrated that neutrophils release bioactive nanovesicles called exosomes that carried proteins associated with immune response, positive regulation of cell communication. Interestingly, we demonstrated that neutrophil exosomes have the capacity to enter the airway smooth muscle cells and modulate their proliferation.
This study higlighted a new pathway of intercellular communication mediated by bioactive neutrophil nanovesicules (exosomes) and underscored their possible contribution to airway remodeling in neutrophilic asthma and their immunoregulation potential in the pathogenesis of an array of other diseases.
EVALUATION OF ANGIOGENESIS IN THE AIRWAYS OF HORSES WITH HEAVES
Herteman N, Bullone M and Lavoie JP. Endoscopic evaluation of angiogenesis in the large airways of horses with heaves using narrow bandimaging. Journal of Veterinary Internal Medicine. J Vet Intern Med. 2016 Mar 1. doi: 10.1111/jvim.13890
Chronic inflammation promotes the formation of new vessels, a phenomenon known as angiogenesis. Narrow band imaging (NBI) endoscopy is a non-invasive technic that enhances the visualization of submucosal vessels. It employs filters producing light of specific blue and green wavelengths corresponding to the peak light absorption of hemoglobin. Using NBI, this study aimed at determining whether the central airways of horses with heaves sustain angiogenesis.
In the trachea, the volume density of small vessels was increased in horses with heaves compared to controls. No difference was found in the carina or bronchi.
NBI imaging of the airways was easily performed in standing unsedated horses. The significance of the increased tracheal vascularity in heaves remains to be ascertained.
Bullone M, Murcia RY, Lavoir JP. Environmental heat and airborne pollen concentration are associated with increased asthma severity in horses. Equine Vet J. 2015 Dec 28. doi: 10.1111/evj.12559.
Environmental heat and airborne pollen concentration are associated with increased asthma severity in horsesHeaves exacerbations are triggered by environmental dusts mostly associated with hay feeding and barn stabling. Due to the increased amount of time that horses spend in the barns during the cold season, the clinical signs of heaves are often most severe during winter months. However, our study has shown that disease exacerbations may occur even when environmental temperatures and humidity increase. Furthermore, the increase in temperature and humidity, we have detected a high concentration of airborne pollen, which could act as non-specific irritants of the airway.
Lavoie JP. Is the time primed for equine asthma? Equine Veterinary Education 2015; 27: 225-226.
Bullone M, Lavoie JP. Asthma "of horses and men"how can equine heaves help us better understand human asthma immunopathology and its functional consequences?
Mol Immunol 2015;66(1):97-105.
There is much confusion regarding the terminology used to describe the non-infectious conditions affecting the lower airway of horses. In an editorial Equine Veterinary Education, Dr Lavoie proposed to use the term Equine asthma to describe what is currently known as heaves, recurrent airway obstruction (RAO), summer pasture associated obstructive pulmonary disease (SPAOPD), and inflammatory airway disease (IAD). There are great similarities between human asthma and these equine conditions, and using this term will facilitate communications between veterinarians and horse owners and trainers. The study of Equine asthma also serves at better understanding human asthma and to improve human health.
BLOOD BIOMARKERS FOR THE FIELD DIAGNOSIS OF IAD
Bullone M, de Lagarde M, Vargas A, Lavoie JP. Serum Surfactant Protein D and Haptoglobin as Potential Biomarkers for Inflammatory Airway Disease in Horses. J Vet Intern Med 2015.
Leclere M, Lavoie-Lamoureux A, Lavoie JP. Acute phase proteins in racehorses with inflammatory airway disease. J Vet Intern Med. 2015; 29(3):940-945.
Inflammatory airway disease (IAD) is the most common cause of chronic cough and exercise intolerance in horses. However, currently, the diagnosis requires the analysis of bronchoalveolar fluids, which is not commonly performed in the field and often requires a reference to a specialized veterinary clinic. One of Dr Lavoie’s research programs aims at indentifying biomarkers that would allow the diagnosis of horses with mild to moderate equine asthma. By combining two biomarkers, it was possible to predict horses with moderate asthma, from controls. However, biomarkers were not sensitive in evaluating racehorses with very mild lower airway inflammation.
AIRWAY SMOOTH MUSCLE REMODELING
Bullone M, Beauchamp G, Godbout M, Martin JG, Lavoie JP. Endobronchial ultrasound reliably quantifies airway smooth muscle remodeling in an equine asthma model. Plos One 2015; 10(9): e0136284.
Chevigny M, Guerin-Montpetit K, Vargas A, Lefebvre Lavoie J, Lavoie JP. Contribution of srf, elk-1 and myocardin to airway smooth muscle remodeling in heaves, an asthma-like disease of horses. Am J Physiol Lung Cell Mol Physiol 2015; 309(1): ajplung 00,050 02015.
Dr. Lavoie and his group have described in the past 10 years the severe changes occurring with the lungs of horses with heaves (severe equine asthma). These studies showed a marked increase in the amount of smooth muscle surrounding the airways of asthmatic horses, and the deposition of the extracellular matrix. They had also found out that once established, these changes are only partially reversible, even after 1 year of the treatment. There is therefore a need to identify horses developing these lung lesions as well as novel therapy to prevent or reverse these changes.
Dr Lavoie’s group has now identified a transcription factor in the remodeling of the airway smooth muscle cells in heaves. However, currently, the study of airway remodeling requires the use of invasive biopsies that cannot be routinely performed in horses. However, by using a state of the art ultrasound probes, it is possible to monitor the remodelling of the airways non-invasively in standing horses. This approach will now be investigated in horses with mild to moderate asthma presented to the Equine Hospital of the Université de Montréal.
SYSTEMIC INFLAMMATION IN HEAVES
Leclere M, Bedard C, Cortes-Dubly ML, Lavoie JP. Blood hypercoagulability and systemic inflammation in horses with heaves. Vet J 2015; 206(1):105-107.
In this study, we reported that the inflammation is not confined to the lungs in horses with heaves (severe equine asthma), and that affected horses have abnormal coagulation profile, which persists even when they are in clinical remission of the disease.