gamma-linolenic-acid and Cystic-Fibrosis

DF Horrobin hypothesized that the low prevalence of lung disease among Eskimos is the result of their diet, which is high in n-3 fatty acids. The n-3 and n-6 fatty acids shunt eicosanoid production away from the arachidonic acid pathway, and hence decrease the production of bronchoconstrictive leukotrienes. Animal studies showed that eicosapentaenoic acid or gamma-linolenic acid supplementation of animals exposed to endotoxins results in decreased effects on thromboxane B(2) and pulmonary vascular resistance. Small human trials confirmed that supplementation with eicosapentaenoic acid results in increased eicosapentaenoic acid in phospholipids and decreased generation of leukotrienes by neutrophils. Hence, a protective effect of such fatty acids in lung disease is biologically plausible. The results of human intervention studies looking at respiratory outcomes have been mixed, but they do suggest a possible difference between long-term and short-term effects. Epidemiologic studies showed possible protective effects against asthma in children, but weak to no evidence of such effects in adults. Results for bronchitis are more positive, although intervention trials are lacking. Recently, a cross-sectional analysis of data from the first National Health and Nutrition Examination Survey reported an approximately 80-mL difference in forced expiratory volume at 1 s between adults with high compared with low fish consumption. This response was not limited to asthmatic subjects. Others found that both fish consumption and n-3 fatty acid consumption (as estimated from food-frequency questionnaires) were protective against physician-diagnosed emphysema and chronic bronchitis and low spirometry values. Only smokers were included in this analysis. These results suggest that dietary fatty acids may play a role in lung disease; further work is needed to elucidate that role.

Topics: Adult; Animals; Asthma; Bronchitis; Child; Cystic Fibrosis; Dietary Fats, Unsaturated; Eicosapentaenoic Acid; Fatty Acids, Unsaturated; gamma-Linolenic Acid; Humans; Lung Diseases; Lung Diseases, Obstructive; Rabbits; Respiratory Function Tests; Swine

Chronic inflammation plays a major role in lung deterioration in cystic fibrosis (CF) patients and anti-inflammatory strategies have beneficial effects. To study the changes seen after a one-year course of low-dose dietary supplements with a mixture of fatty acids in adult patients with CF in chronic inflammation, pulmonary status (lung function, respiratory exacerbations and antibiotic consumption), quality of life and anthropometric parameters.. Seventeen adult subjects with CF received 324 mg of eicosapentaenoic, 216 mg of docosahexaenoic, 480 mg of linoleic and 258 mg of gammalinolenic acid daily. We assessed inflammation markers, spirometry parameters, number and severity of respiratory exacerbations, antibiotic consumption, quality of life (St George's QoL), anthropometric parameters and serum phospholipid fatty acid composition.. At the end of the treatment period TNF alpha levels fell significantly and its soluble receptors (60 and 80) rose significantly. Levels of IgG and IgM anti-oxidized LDL antibodies fell significantly. Spirometry improved significantly. Annual respiratory exacerbations and days of antibiotic treatment fell significantly. The improvement in QoL was not significant. Serum levels of docosahexaenoic, total omega-3 and linoleic acid rose significantly and more favourable profiles were seen in monoenoic acids, arachidonic acid and the arachidonic/docosahexaenoic ratio. The fat-free mass and hand grip dynamometry improved significantly.. Low-dose supplements of n-3 and gammalinolenic fatty acids over a long period (one year) appears to improve pulmonary status (lung function, respiratory exacerbations and antibiotic consumption), inflammatory and anthropometric parameters in adults with CF.

Topics: Adolescent; Adult; Anthropometry; Autoantibodies; Body Composition; Cystic Fibrosis; Dietary Supplements; Docosahexaenoic Acids; Eicosapentaenoic Acid; Female; gamma-Linolenic Acid; Humans; Inflammation; Linoleic Acid; Lipoproteins, LDL; Male; Quality of Life; Receptors, Tumor Necrosis Factor; Respiratory Function Tests; Respiratory Tract Infections; Severity of Illness Index; Sputum; Tumor Necrosis Factor-alpha; Vitamin E; Young Adult

Supplements of evening primrose oil (Oenothera biennis), which contains at least 72% linoleic (18:2n-6) and 7% gamma-linolenic (18:3 n-6) acids (expressed as % fatty acid methyl esters) were given to sixteen cystic fibrosis patients for a period of 12 months. Clinical observations showed no significant changes in patients' weights or respiratory function throughout. Linoleic acid levels in plasma and erythrocyte membranes increased significantly during the first 6 months but this increase was not sustained at its initial level. After supplementation was discontinued reversion to baseline (low) levels occurred within 4 months. Levels of plasma prostaglandins (PG) and urinary PG metabolites varied among individuals over a wide range, and urinary PGF2 alpha metabolites fell during the supplementation. There was a significant fall in sweat sodium concentrations after 6 weeks of supplementation, but sweat chloride was unchanged. It is not known whether the effect of essential fatty acids on sweat Na+ reflects changes in cell membrane conformation or if there is a direct effect on Na+ pump activity.

Topics: Adolescent; Adult; Child; Child, Preschool; Chlorides; Clinical Trials as Topic; Cystic Fibrosis; Dietary Fats, Unsaturated; Electrolytes; Fatty Acids, Essential; Female; gamma-Linolenic Acid; Humans; Linoleic Acids; Lipids; Male; Oenothera biennis; Plant Oils; Sodium; Sweat

This study examined the effects of supplementing patients with cystic fibrosis daily for 4 weeks with 1,500 mg borage oil, containing 330 mg gamma-linolenic acid, on the fatty acid composition of serum phospholipids (PL) and cholesteryl esters (CE). Vital capacity and forced expiratory volume in 1 s were also measured before and after treatment. In serum PL the content of arachidonic acid (AA) increased and that of palmitic acid decreased significantly after borage oil administration. In serum CE dihomogamma-linolenic acid increased whereas docosahexaenoic acid decreased significantly. In this lipid class, AA and the sum of AA plus its precursor, dihomogamma-linolenic acid, increased significantly with the dose fed. A positive correlation was found between change in vital capacity and change in linoleic acid content of serum CE and AA content of serum PL.

Topics: Adolescent; Adult; Arachidonic Acid; Child; Cholesterol Esters; Cystic Fibrosis; Diet; Fatty Acids; Female; gamma-Linolenic Acid; Humans; Male; Phospholipids; Respiratory Function Tests