Acute exercise is associated with reduced exhaled nitric oxide in physically inactive adults with asthma.
BACKGROUND
Although exercise has multiple health benefits, relatively little attention has been paid to its potential therapeutic effects in those with asthma.


OBJECTIVE
To examine the effects of acute exercise on inflammation in physically inactive and active adults with asthma.


METHODS
Fourteen adults with asthma (n = 6 physically inactive, n = 8 physically active) completed (1) 30 minutes of moderate-intensity exercise on a treadmill and (2) 30 minutes of rest in random order, with 4 weeks between sessions. Exhaled nitric oxide (eNO) was measured before and after the intervention (0, 0.5, 1, 2, 4, and 24 hours). Blood inflammatory mediators were measured before and after the intervention (0, 2, and 24 hours).


RESULTS
Physically inactive participants had a significant decrease in eNO 4 hours after exercise (-4.8 ppb, -6.4 to -0.5 ppb, P = .028), which was not observed in physically active participants (P = .362). Interluekin-1 receptor antagonist increased in the physically inactive group 2 hours after exercise, with this increase strongly correlated with the decrease in eNO at 4 hours (R = -0.685, P = .007) and 24 hours (R = -0.659, P = .014) after exercise. Interleukin-6 was increased significantly 2 hours after exercise in physically inactive participants. Blood neutrophils and nuclear factor erythroid 2-like 2 gene expression were increased 2 hours after exercise in the overall cohort.


CONCLUSIONS
This study demonstrates that acute moderate-intensity exercise is associated with decreased eNO in physically inactive adults with asthma and suggests that interluekin-1 receptor antagonist could have a role in mediating this effect. The attenuated response in physically active participants might be due to the sustained anti-inflammatory effects of exercise training. Future studies should investigate the impact of exercise intensity and exercise training on airway inflammation in those with asthma.


BACKGROUND
Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au), registration number ACTRN12613001014741.
Centre for Asthma and Respiratory Diseases, The University of Newcastle, New Lambton Heights, New South Wales, Australia; School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, New South Wales, Australia; Lung and Allergy Research Centre, School of Medicine, The University of Queensland, Brisbane, Queensland, Australia. Electronic address: Hayley.Scott@newcastle.edu.au.
Hayley A
HA
Scott
Centre for Asthma and Respiratory Diseases, The University of Newcastle, New Lambton Heights, New South Wales, Australia; School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, New South Wales, Australia.
Jennifer R
JR
Latham
School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, New South Wales, Australia.
Robin
R
Callister
Centre for Asthma and Respiratory Diseases, The University of Newcastle, New Lambton Heights, New South Wales, Australia; Department of Respiratory and Sleep Medicine, John Hunter Hospital, New Lambton Heights, New South Wales, Australia.
Jeffrey J
JJ
Pretto
Centre for Asthma and Respiratory Diseases, The University of Newcastle, New Lambton Heights, New South Wales, Australia; School of Medicine and Public Health, The University of Newcastle, Callaghan, New South Wales, Australia.
Katherine
K
Baines
Department of Respiratory and Sleep Medicine, John Hunter Hospital, New Lambton Heights, New South Wales, Australia.
Nick
N
Saltos
Lung and Allergy Research Centre, School of Medicine, The University of Queensland, Brisbane, Queensland, Australia.
John W
JW
Upham
Centre for Asthma and Respiratory Diseases, The University of Newcastle, New Lambton Heights, New South Wales, Australia; School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, New South Wales, Australia.
Lisa G
LG
Wood
D000293:Adolescent; D000328:Adult; D000368:Aged; D000893:Anti-Inflammatory Agents; D001249:Asthma / Q000378:metabolism* / Q000628:therapy; D001944:Breath Tests; D016207:Cytokines / Q000096:biosynthesis; D015444:Exercise / Q000502:physiology*; D045853:Exhalation; D005260:Female; D006801:Humans; D007249:Inflammation / Q000628:therapy; D018836:Inflammation Mediators / Q000097:blood; D053590:Interleukin 1 Receptor Antagonist Protein / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood / Q000276:immunology; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D051267:NF-E2-Related Factor 2 / Q000096:biosynthesis; D009504:Neutrophils / Q000276:immunology; D009569:Nitric Oxide / Q000378:metabolism*; D066232:Pulmonary Elimination; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors; D057185:Sedentary Behavior; D013482:Superoxide Dismutase / Q000378:metabolism; D055815:Young Adult
D000893:Anti-Inflammatory Agents; D016207:Cytokines; C508600:IL6 protein, human; D018836:Inflammation Mediators; D053590:Interleukin 1 Receptor Antagonist Protein; D015850:Interleukin-6; D051267:NF-E2-Related Factor 2; D017472:Receptors, Interleukin-1; D009569:Nitric Oxide; D013482:Superoxide Dismutase