gamma-linolenic-acid and Hypersensitivity

Topics: Animals; Anti-Bacterial Agents; Antineoplastic Agents; Dermatitis, Atopic; Dermatologic Agents; Dust; Eicosapentaenoic Acid; Fatty Acids, Essential; gamma-Linolenic Acid; Humans; Hypersensitivity; Linoleic Acids; Mites; Oenothera biennis; Phosphodiesterase Inhibitors; Plant Oils; Staphylococcal Infections; Steroids; Ultraviolet Rays

Patients with atopic eczema and a mixture of allergic illnesses show biochemical evidence suggesting impairment in the desaturation of linoleic acid and linolenic acid by the enzyme delta-6 dehydrogenase. Consequences of this enzyme defect are 1) diminished synthesis of the 20-carbon polyunsaturated fatty acids, which are prostaglandin precursors and 2) a reduction in the concentration of double bonds in the cell membrane. A distortion in the production of prostaglandins and leukotrienes, which might result from this block, can account for the immunological defects of atopy and a variety of clinical symptoms experienced by atopic individuals. Dietary supplementation with essential fatty acids relieves the signs and symptoms of atopic eczema, may improve other types of allergic inflammation, and may also correct coexisting symptoms as diverse as excessive thirst and dysmenorrhea. Further research is suggested to test the hypothesis that some atopic states represent a condition of essential fatty acid dependency owing to defective desaturation of dietary fatty acids.

Topics: Adult; alpha-Linolenic Acid; Cardiac Complexes, Premature; Child; Delta-5 Fatty Acid Desaturase; Dietary Fats; Eczema; Encopresis; Enuresis; Fatty Acid Desaturases; Fatty Acids, Essential; Fatty Acids, Unsaturated; Female; Food, Fortified; gamma-Linolenic Acid; Humans; Hypersensitivity; Linoleic Acid; Linoleic Acids; Linolenic Acids; Linoleoyl-CoA Desaturase; Linseed Oil; Male; Middle Aged; Oenothera biennis; Plant Oils; Prostaglandins; Thirst

Twenty dogs with atopy or idiopathic pruritus were treated in a double-blinded clinical trial with computer-randomized and computer-generated sequences of 4 fatty acid-containing products: evening primrose oil, cold water marine fish oil, DVM Derm Caps, and EfaVet. Each dog received each product for a 2-week period. Five of 20 dogs (25%) had a good-to-excellent reduction in their level of pruritus with at least 1 of the products: evening primrose oil (2 dogs), DVM Derm Caps (1), EfaVet (1), DVM Derm Caps and cold water marine fish oil (1). Only 1 dog experienced a side effect (loose stools). Clinical response to fatty acid supplements appeared to be quite individualized, and independent of age, breed, sex, weight, duration of disease, specific diagnosis, or number of positive intradermal test reactions.

Topics: Animals; Dermatologic Agents; Dog Diseases; Dogs; Fatty Acids, Essential; Female; Fish Oils; gamma-Linolenic Acid; Hypersensitivity; Linoleic Acids; Male; Oenothera biennis; Plant Oils; Pruritus

Dietary fatty acids have been shown to influence allergic sensitisation. Both n-3 and n-6 PUFA are involved in targeted mediation of inflammatory responses during allergic sensitisation and manifestation of atopic diseases. In the present experiments we investigated whether supplementation of DHA-enriched fish oil partly substituting dietary sunflower-seed oil, in comparison with sunflower-seed oil, supplemented to mice influences fatty acid composition of serum lipid classes. The effects of the two different diets were also investigated depending on allergic sensitisation. Supplementation of DHA and EPA in doses of 2 and 0.12 % (w/w) to non-sensitised and sensitised mice resulted in significantly increased percentile contributions of DHA to all lipid classes. In contrast, serum values of the n-6 PUFA arachidonic acid (AA) were significantly lower, both in non-sensitised and sensitised mice fed the DHA-enriched diet. The fatty acid composition of serum lipids also reflected allergic sensitisation: the EPA:AA ratio in TAG, cholesteryl esters and phospholipids in non-supplemented animals fell to 23, 29 and 29 % respectively of the original value after allergic sensitisation, whereas it decreased to 70, 80 and 76 % respectively only in the animals supplemented with DHA. In summary, allergic sensitisation alone decreased significantly the EPA:AA ratios in serum TAG, while concomitant supplementation of DHA-enriched fish oil ameliorated this decrease. We postulate from the present results that the amelioration of the severity of allergic sensitisation after DHA supplementation may be linked to altered ratios of the eicosanoid precursors EPA and AA as well as DHA needed for further metabolic activation to pro- or anti-inflammatory bioactive lipids.

Topics: Animals; Arachidonic Acid; Cholesterol Esters; Dietary Supplements; Docosahexaenoic Acids; Eicosapentaenoic Acid; Enzyme-Linked Immunosorbent Assay; Fatty Acids; Fatty Acids, Omega-3; Female; Fish Oils; Galactosylceramides; gamma-Linolenic Acid; Hypersensitivity; Mice; Mice, Inbred BALB C; Models, Animal; Ovalbumin; Phospholipids; Plant Oils; Sunflower Oil; Triglycerides

Topics: Animals; Drug Therapy, Combination; gamma-Linolenic Acid; Humans; Hypersensitivity; Neoplasms, Experimental; Risk Factors; Vitamin E

Fourteen cats with crusting dermatoses ('miliary dermatitis') were supplemented with various combinations of evening primrose oil and fish oil. The cutaneous signs improved when the cats were supplemented with either evening primrose oil alone or with a combination of evening primrose oil and fish oil. Fish oil alone was unable to maintain the remission and the cutaneous signs deteriorated. The subsequent administration of a combination of the two oils resulted in a resolution of the dermatosis.

Topics: Animals; Bites and Stings; Cat Diseases; Cats; Dermatitis; Dermatologic Agents; Fatty Acids; Fatty Acids, Essential; Female; Fish Oils; gamma-Linolenic Acid; Hypersensitivity; Linoleic Acids; Male; Oenothera biennis; Plant Oils; Siphonaptera