Effect of n-3 polyunsaturated fatty acids in asthma after low-dose allergen challenge.
BACKGROUND
We investigated the anti-inflammatory potential of n-3 polyunsaturated fatty acids (PUFA) on specific bronchial inflammation. Allergic asthmatics were challenged using a low-dose allergen provocation model.


METHODS
Our parallel double-blinded study randomly assigned 23 house dust mite-allergic asthmatics (aged 22-29 years; 13 females, 10 males) to dietary supplementation with either an n-3 PUFA-enriched fat blend (0.69 g/day) or placebo for 5 weeks. After 3 weeks, the patients were challenged daily with low doses of mite allergen for 2 weeks. Primary outcome parameters were effects on lung function (forced expiratory volume in 1 s, FEV(1)) and exhaled nitric oxide (eNO) as a marker of bronchial inflammation.


RESULTS
Even before the bronchial challenge, eNO was significantly lower in the n-3 PUFA group (p=0.014). Levels of eNO increased during allergen exposure in both groups, but differences in means were significantly lower in the n-3 PUFA group (p=0.022). During the low-dose allergen challenge, there were no differences between the groups with regard to symptoms, FEV(1) or the allergen dose required to induce deterioration of lung function (PD(20)). Numbers of sputum eosinophils did not differ significantly, while serum eosinophils (10.1+/-0.1.84 vs. 5.79+/-0.69%) as well as changes in eosinophilic cationic protein (20.5+/-9.93 vs. -1.68+/-4.36 ng/ml) and in vitro cysteinyl leukotriene release (2,889+/-872 vs. 1,120+/-173 ng/ml) were significantly lower in the n-3 PUFA group (p<0.05 each).


CONCLUSIONS
Our results provide evidence that dietary supplementation with n-3 PUFA is able to reduce bronchial inflammation even after low-dose allergen challenge.
Schubert
R
R
Department of Pediatrics/ZAFES, J.W. Goethe University, Frankfurt/Main, Germany.
Kitz
R
R
Beermann
C
C
Rose
M A
MA
Lieb
A
A
Sommerer
P C
PC
Moskovits
J
J
Alberternst
H
H
Böhles
H J
HJ
Schulze
J
J
Zielen
S
S
D000328:Adult; D039741:Antigens, Dermatophagoides / Q000276:immunology; D001249:Asthma / Q000178:diet therapy* / Q000276:immunology / Q000503:physiopathology; D001944:Breath Tests; D001985:Bronchial Provocation Tests; D002452:Cell Count; D003545:Cysteine / Q000378:metabolism; D004311:Double-Blind Method; D004804:Eosinophils / Q000166:cytology; D004912:Erythrocytes / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000097:blood / Q000378:metabolism / Q000627:therapeutic use*; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007958:Leukocyte Count; D007962:Leukocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D015289:Leukotrienes / Q000378:metabolism; D008297:Male; D009569:Nitric Oxide / Q000378:metabolism; D013183:Sputum / Q000166:cytology; D016896:Treatment Outcome; D055815:Young Adult
D039741:Antigens, Dermatophagoides; D015525:Fatty Acids, Omega-3; D015289:Leukotrienes; C112381:cysteinyl-leukotriene; D009569:Nitric Oxide; D003545:Cysteine