promega and Asthma

The effects of taking 18 capsules a day of Max-EPA (3.2 g/day eicosapentaenoic acid) on clinical symptoms and bronchial hyperresponsiveness were studied in pollen-sensitive subjects over a pollen season in a parallel, double-blind, placebo-controlled (olive oil) fashion. The study was conducted over the 1990 and 1991 pollen seasons in London, England. A total of 37 nonsmoking pollen-sensitive asthmatic subjects were entered into the trial, and 25 completed the 6-month study period over the 2 yr. The preseasonal geometric mean PD35 SGaw of histamine for the fish oil (n = 12) and placebo (n = 9) groups were 0.62 and 0.42 mumol, respectively. During the middle of the pollen season, histamine PD35 SGaw fell significantly for both the fish oil (0.11 mumol, p < 0.0001) and placebo groups (0.10 mumol, p < 0.007), indicating increased bronchial reactivity compared with preseasonal values, but there was no significant difference between the groups. Similarly, morning and evening peak expiratory flow (PEF), diurnal variability in PEF, nocturnal cough and wheeze, daytime wheeze, and activity, as well as nasal symptoms and increased usage of medication, were not significantly different between the groups. Compliance was confirmed by neutrophil and plasma phospholipid analysis, which showed significant rises in eicosapentaenoic acid content in the fish oil group but not in the placebo group. We conclude that dietary fish oil supplementation does not prevent seasonal hay fever and asthma in pollen-sensitive subjects during the pollen season.

Topics: Adult; Asthma; Bronchial Provocation Tests; Docosahexaenoic Acids; Double-Blind Method; Drug Combinations; Eicosapentaenoic Acid; Fatty Acids, Omega-3; Female; Fish Oils; Histamine; Humans; Leukocyte Count; Male; Neutrophils; Peak Expiratory Flow Rate; Phospholipids; Pollen; Rhinitis, Allergic, Seasonal

The effects of dietary supplementation with fish oil lipids on the airways responses to allergen and neutrophil biochemistry and function have been studied in 17 atopic asthmatic subjects. Nine subjects received 18 capsules of Max-EPA (3.2 g eicosapentaenoic acid and 2.2 g docosahexaenoic acid) a day and eight subjects received identical capsules containing olive oil, for 10 wk in a double-blind fashion. There were no differences between prediet values and those observed after dietary supplementation with Max-EPA or placebo in the dose of allergen causing an acute asthmatic response as assessed by a 35% fall in specific airways conductance (PD35), the extinction dose of allergen on skin prick testing, the histamine PD35, or the total serum IgE concentrations. Twelve of the 17 subjects developed late asthmatic responses after allergen challenge prediet. Six of these subjects received Max-EPA, and six received placebo capsules. As compared to prediet values, the magnitude of the allergen-induced late asthmatic response was significantly attenuated from 2 to 7 h after allergen challenge following dietary supplementation with Max-EPA (p less than 0.005) but not with placebo. The attenuation of the late response was not accompanied by any significant change in the clinical severity of disease as assessed by diurnal peak expiratory flow rates, symptom scores, or bronchodilator drug usage.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; Airway Resistance; Allergens; Asthma; Bronchi; Bronchial Provocation Tests; Chemotaxis, Leukocyte; Docosahexaenoic Acids; Double-Blind Method; Drug Combinations; Eicosapentaenoic Acid; Fatty Acids; Fatty Acids, Unsaturated; Female; Fish Oils; Histamine; Humans; Immunoglobulin E; Leukotriene B4; Male; Neutrophils; Skin Tests; Time Factors

Recruitment of inflammatory leucocytes to the airways may play a part in the pathogenesis of asthma. As dietary enrichment with fish oil lipids can suppress leucocyte function, the effect of these lipids on asthma control and neutrophil function was studied in 20 subjects with mild asthma. Twelve subjects received capsules containing 3.2 g of eicosapentaenoic acid and 2.2 g of docosahexaenoic acid daily and eight subjects received placebo capsules containing olive oil for 10 weeks in a double blind fashion. Baseline specific airways conductance, airways responsiveness to histamine and exercise, diurnal peak expiratory flow, symptom scores, and bronchodilator use were measured. Neutrophil fatty acid composition was evaluated by gas chromatography, calcium ionophore induced neutrophil leukotriene (LT)B4 and LTB5 generation were measured by reverse phase high performance liquid chromatography and radioimmunoassay, and neutrophil chemotactic responses to formyl-methionyl-leucyl-phenylalanine (FMLP) and LTB4 were assessed by a microchemotaxis technique. Although the fish oil supplemented diet produced a greater than 10 fold increase in the eicosapentaenoic acid content of neutrophil phospholipids, there was no significant change in airways responsiveness to histamine or any change in any of the clinical measurements. After dietary supplementation with fish oil there was a 50% inhibition of total LTB (LTB4 + LTB5) generation by ionophore stimulated neutrophils and neutrophil chemotaxis was substantially suppressed. Neutrophil function remained unchanged in the placebo group. It is concluded that in subjects with mild asthma a fish oil enriched diet attenuates neutrophil function without changing the severity of asthma.

Topics: Adolescent; Adult; Airway Resistance; Asthma; Asthma, Exercise-Induced; Chemotaxis, Leukocyte; Dietary Fats, Unsaturated; Docosahexaenoic Acids; Double-Blind Method; Drug Combinations; Eicosapentaenoic Acid; Fatty Acids; Fatty Acids, Unsaturated; Female; Fish Oils; Humans; Male; Neutrophils

The effect of a fish oil enriched diet containing about 3 g of eicosapentaenoic acid was studied in 10 patients with aspirin intolerant asthma. Subjects were studied during six weeks on a control diet followed by six weeks on the fish oil diet in a single blind study design. They were asked to record their peak expiratory flow (PEF) twice daily, bronchodilator and steroid doses, and subjective ratings of pulmonary symptoms on diary cards. There were no significant changes in symptom scores over the six weeks of either the control diet or the fish oil diet. PEF values, however, were significantly lower during the fifth and sixth week of the fish oil diet than during the control diet (308 v 262 l/min week 5 and 306 v 256 l/min week 6). Bronchodilator usage was also greater during the fifth and sixth week of the fish oil diet than during the control period (12.0 v 7.4 and 13.0 v 7.4 puffs a day in weeks 5 and 6). This pilot study suggests that fish diets may have a deleterious effect on patients with aspirin intolerant asthma.

Topics: Adult; Aged; Albuterol; Aspirin; Asthma; Dietary Fats, Unsaturated; Docosahexaenoic Acids; Drug Combinations; Eicosapentaenoic Acid; Fatty Acids; Fatty Acids, Unsaturated; Female; Fish Oils; Humans; Male; Middle Aged; Peak Expiratory Flow Rate; Thromboxane B2