The Relationship Between Airway Wall Stiffness And Airway Inflammation In Asthma

Author(s):  
Jessica A. Kermode ◽  
Nathan Brown ◽  
Norbert Berend ◽  
Gregory King ◽  
Cheryl Salome
Respiration ◽  
2020 ◽  
pp. 1-11
Author(s):  
Louis-Philippe Boulet ◽  
Marie-Eve Boulay ◽  
Harvey O. Coxson ◽  
Cameron J. Hague ◽  
Joanne Milot ◽  
...  

<b><i>Background:</i></b> The development of irreversible airway obstruction (IRAO) in asthma is related to lung/airway inflammatory and structural changes whose characteristics are likely influenced by exposure to tobacco smoke. <b><i>Objective:</i></b> To investigate the interplay between airway and lung structural changes, airway inflammation, and smoking exposure in asthmatics with IRAO. <b><i>Methods:</i></b> We studied asthmatics with IRAO who were further classified according to their smoking history, those with ≥20 pack-years of tobacco exposure (asthmatics with smoking-related IRAO [AwS-IRAO]) and those with &#x3c;5 pack-years of tobacco exposure (asthmatics with nonsmoking-related IRAO [AwNS-IRAO]). In addition to recording baseline clinical and lung function features, all patients had a chest computed tomography (CT) from which airway wall thickness was measured and quantitative and qualitative assessment of emphysema was performed. The airway inflammatory profile was documented from differential inflammatory cell counts on induced sputum. <b><i>Results:</i></b> Ninety patients were recruited (57 AwS-IRAO and 33 AwNS-IRAO). There were no statistically significant differences in the extent of emphysema and gas trapping between groups on quantitative chest CT analysis, although Pi10, a marker of airway wall thickness, was significantly higher in AwS-IRAO (<i>p</i> = 0.0242). Visual analysis showed a higher prevalence of emphysema (<i>p</i> = 0.0001) and higher emphysema score (<i>p</i> &#x3c; 0.0001) in AwS-IRAO compared to AwNS-IRAO and distribution of emphysema was different between groups. Correlations between radiological features and lung function were stronger in AwS-IRAO. In a subgroup analysis, we found a correlation between airway neutrophilia and emphysematous features in AwS-IRAO and between eosinophilia and both airway wall thickness and emphysematous changes in AwNS-IRAO. <b><i>Conclusions:</i></b> Although bronchial structural changes were relatively similar in smoking and nonsmoking patients with asthma and IRAO, emphysematous changes were more predominant in smokers. However, neutrophils in AwS-IRAO and eosinophils in AwNS-IRAO were associated with lung and airway structural changes.


1987 ◽  
Vol 63 (2) ◽  
pp. 707-712 ◽  
Author(s):  
V. Soland ◽  
G. Brock ◽  
M. King

In our previous study, we investigated the relationship between mucus rheology, depth of mucus layer, and clearance by simulated cough. The purpose of the present study was to examine the effect of airway wall flexibility on the clearance of mucuslike gels. Transient airflows similar to cough were generated by both positive and negative pressure, the latter to mimic the dynamic compression that occurs during real cough. As in the previous study, the trachea was modeled as a trough of rectangular cross section with only the bottom lined with the mucus simulant. Clearance was followed by observing the displacement of marker particles. Since cough clearance is intimately related to wave formation in the mucus blanket, we hypothesized that clearance might be impeded if the wave formation occurred simultaneously in the wall and its lining layer. Thus, in one set of experiments the bottom rigid surface of the model trachea was replaced with a frame over which a flexible membrane could be drawn, whereas in the other set the rigid top was replaced by the frame. We also examined the effect of negative-pressure cough in excised canine tracheae, comparing the case where the tracheal membrane was free to deform vs. the case where it was secured. For the rigid-walled model, clearance by positive or negative pressure, with matched flow pattern, was the same. With the mucus simulant lining the flexible bottom surface, clearance increased with increasing membrane flexibility for negative-pressure cough and decreased for positive-pressure cough.(ABSTRACT TRUNCATED AT 250 WORDS)


2002 ◽  
Vol 166 (12) ◽  
pp. 1590-1595 ◽  
Author(s):  
Alan L. James ◽  
Peta S. Maxwell ◽  
Gladys Pearce-Pinto ◽  
John G. Elliot ◽  
Neil G. Carroll

2015 ◽  
Vol 12 (6) ◽  
pp. 813-820 ◽  
Author(s):  
Miriam Gjerdevik ◽  
Thomas B. Grydeland ◽  
George R. Washko ◽  
Harvey O. Coxson ◽  
Edwin K. Silverman ◽  
...  

2008 ◽  
Vol 104 (6) ◽  
pp. 1601-1610 ◽  
Author(s):  
Ana Cojocaru ◽  
Charles G. Irvin ◽  
Hans C. Haverkamp ◽  
Jason H. T. Bates

Allergic inflammation is known to cause airway hyperresponsiveness in mice. However, it is not known whether inflammation affects the stiffness of the airway wall, which would alter the load against which the circumscribing smooth muscle shortens when activated. Accordingly, we measured the time course of airway resistance immediately following intravenous methacholine injection in acutely and chronically allergically inflamed mice. We estimated the effective stiffness of the airway wall in these animals by fitting to the airway resistance profiles a computational model of a dynamically narrowing airway embedded in elastic parenchyma. Effective airway wall stiffness was estimated from the model fit and was found not to change from control in either the acute or chronic inflammatory groups. However, the acutely inflamed mice were hyperresponsive compared with controls, which we interpret as reflecting increased delivery of methacholine to the airway smooth muscle through a leaky pulmonary endothelium. These results support the notion that acutely inflamed BALB/c mice represent an animal model of functionally normal airway smooth muscle in a transiently abnormal lung.


Kardiologiia ◽  
2021 ◽  
Vol 61 (3) ◽  
pp. 57-65
Author(s):  
A. A. Akopyan ◽  
K. I. Kirillova ◽  
I. D. Strazhesko ◽  
L. M. Samokhodskaya ◽  
Ya. A. Orlova

Aim    Activation of the renin-angiotensin-aldosterone system, decreased nitric oxide production, chronic inflammation, and oxidative stress result in subclinical changes in the arterial wall, which favor the development of cardiovascular diseases (CVD). The effect of allelic gene variants that encode the proteins participating in pathogenetic pathways of age-associated diseases with subclinical changes in the arterial wall [increased pulse wave velocity (PWV), increased intima-media thickness, endothelial dysfunction (ED), presence of atherosclerotic plaques (ASP)] are understudied. This study analyzed the relationship between AGT, ACE, NOS3 TNF, MMP9, and CYBA gene polymorphism and the presence of subclinical changes in the arterial wall, including the dependence on risk factors for CVD, in arbitrarily healthy people of various age.Material and methods    The relationship of polymorphisms с.521С>Т of AGT gene, Ins>Del of AСE gene, с.894G>T of NOS3 gene, – 238G>A of TNF gene, – 1562С>T of MMP9 gene, and c.214Т>С of CYBA gene with indexes of changes in the arterial wall and risk factors for CVD was studied in 160 arbitrarily healthy people by building models of multiple logistic regression and also by analyzing frequencies of co-emergence of two signs with the Pearson chi-squared test (χ2) and Fisher exact test.Results    The DD-genotype of Ins>Del ACE gene polymorphism was correlated with increased PWV (p=0.006; odds ratio (OR) =3.41, 95 % confidence interval (CI): 1.48–8.67) and ED (p=0.014; OR=2.60, 95 % CI: 1.22–5.68). The GG genotype of с.894G>T NOS3 gene polymorphism was correlated with ED (p=0.0087; OR=2.65, 95 % CI: 1.26–5.72); the ТТ-genotype of с.894G>T NOS3 gene polymorphism was correlated with ASP (p=0.033; OR=0.034, 95 % CI: 0.001–0.549).Conclusion    Polymorphic variants of AСE and NOS3 genes correlated with ED, increased arterial wall stiffness, and the presence of subclinical changes in the arterial wall.


Sign in / Sign up

Export Citation Format

Share Document