linoleic-acid and Eczema

The last two decades have seen an increase in the prevalence of asthma, eczema, and allergic rhinitis in developed countries. This increase has been paralleled by a fall in the consumption of saturated fat and an increase in the amount of polyunsaturated fat in the diet. This is due to a reduction in the consumption of animal fat and an increase in the use of margarine and vegetable oils containing omega-6 polyunsaturated fatty acids (PUFAs), such as linoleic acid. There is also evidence for a decrease in the consumption of oily fish which contain omega-3 PUFAs, such as eicosapentaenoic acid. In a number of countries, there are social class and regional differences in the prevalence of allergic disease, which are associated with differences in the consumption of PUFAs. Linoleic acid is a precursor of arachidonic acid, which can be converted to prostaglandin E2 (PGE2), whereas eicosapentaenoic acid inhibits the formation of PGE2. PGE2 acts on T-lymphocytes to reduce the formation of interferon-gamma (IFN-gamma) without affecting the formation of interleukin-4 (IL-4). This may lead to the development of allergic sensitization, since IL-4 promotes the synthesis of immunoglobulin E (IgE), whereas IFN-gamma has the opposite effect. Changes in the diet may explain the increase in the prevalence of asthma, eczema and allergic rhinitis. The effects of diet may be mediated through an increase in the synthesis of prostaglandin E2 which in turn can promote the formation of immunoglobulin E.

Topics: Animals; Arachidonic Acids; Asthma; Developed Countries; Dietary Fats; Dietary Fats, Unsaturated; Dinoprostone; Eczema; Eicosapentaenoic Acid; Fatty Acids; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Fatty Acids, Unsaturated; Feeding Behavior; Fishes; Humans; Immunoglobulin E; Interferon-gamma; Interleukin-4; Linoleic Acid; Linoleic Acids; Margarine; Plant Oils; Prevalence; Respiratory Hypersensitivity; Rhinitis; Social Class; T-Lymphocytes

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

Atopic dermatitis (AD), chronic eczema, and pruritus hiemalis are a set of prevalent chronic xerotic skin disorders that share clinical features such as dryness, scales, and pruritus. A ceramide deficiency and defective epidermal functions are common in these diseases. This study was designed to assess the effect of ceramide-linoleic acid (LA-Cer)-containing moisturizer as an adjunctive therapy in the treatment of AD, chronic eczema, and pruritus hiemalis. In a 2-month study, patients with one of these three diseases were divided into two groups. The control group was treated with mometasone furoate (0.1%) cream (MF), whereas the treatment group received 0.1% MF in combination with an LA-Cer-containing moisturizer. Capacitance and transepidermal water loss were measured in normal and lesional skin, along with Eczema Assessment Severity Index and pruritus scores at Weeks 0, 2, 4, and 8. The results showed that tropical applications of an LA-Cer-containing moisturizer in combination with a topical glucocorticoid accelerated the reestablishment of epidermal permeability barrier and the amelioration of pruritus in patients with AD and pruritus hiemalis. However, it did not provide the same effect for chronic eczema. Thus, the efficacy of this combination therapy for this set of xerotic disorders requires further evaluation.

Topics: Administration, Cutaneous; Ceramides; Dermatitis, Atopic; Dermatologic Agents; Eczema; Electric Capacitance; Emollients; Glucocorticoids; Humans; Linoleic Acid; Mometasone Furoate; Pruritus; Severity of Illness Index; Treatment Outcome; Water Loss, Insensible

Topics: Adult; Dermatitis, Atopic; Dietary Supplements; Double-Blind Method; Eczema; Epidermis; Fatty Acids, Omega-3; Fatty Acids, Omega-6; Fatty Acids, Unsaturated; Female; Humans; Hydroxyeicosatetraenoic Acids; Linoleic Acid; Linoleic Acids; Male; Pilot Projects; Placebos; Skin

The major theory implicating diet with allergic diseases is associated with altered food consumption and subsequent changes in fatty acid composition.. To investigate fatty acid compositions among infants with atopic and non-atopic eczema and healthy infants and to evaluate the expediency of non-invasive cheek cell phospholipid fatty acid composition as a marker in patients with eczema.. Diagnosis of eczema in infants was confirmed clinically and by positive (atopic eczema, n=6) or negative (non-atopic eczema, n=6) skin prick testing in comparison with controls (n=19). The fatty acid compositions of infant cheek cell and serum phospholipids and breast milk total lipids were analysed by gas chromatography.. The distinction between atopic and non-atopic eczema was manifested in cheek cell phospholipids as linoleic acid (14.69 (13.67-15.53)% of total fatty acids; the median (interquartile range)), the sum of n-6 fatty acids (19.94 (19.06-20.53)%) and the sum of polyunsaturated fatty acids (22.70 (21.31-23.28)%) were higher in infants with atopic eczema compared with non-atopic eczema (12.69 (10.87-13.93); 17.72 (15.63-18.91) and 19.90 (17.64-21.06), respectively; P<0.05) and controls (12.50 (12.16-13.42); 18.19 (17.43-18.70) and 20.32 (19.32-21.03), respectively; P<0.05). Serum phospholipid gamma-linolenic acid was lower in both atopic and non-atopic eczema compared with controls (P<0.05) and additionally eicosapentaenoic acid was higher in atopic eczema compared with controls (P<0.05).. These preliminary results suggest differences in fatty acid compositions between the two types of eczema, calling for further evaluation in a larger setting. The two types of eczema may be regulated by different immunological processes, and fatty acids may have a more profound role in the atopic type.

Topics: alpha-Linolenic Acid; Case-Control Studies; Cheek; Chromatography, Gas; Dermatitis, Atopic; Eczema; Fatty Acids; Humans; Infant; Infant, Newborn; Linoleic Acid; Lipids; Milk, Human; Mouth Mucosa; Phospholipids; Statistics, Nonparametric

Topics: Anemia; Anemia, Hypochromic; Child; Eczema; Fatty Acids; Fatty Acids, Unsaturated; Hematologic Diseases; Humans; Infant; Linoleic Acid

Topics: Arachidonic Acid; Child; Dermatitis, Atopic; Eczema; Humans; Infant; Linoleic Acid

Topics: Arachidonic Acid; Eczema; Fatty Acids; Humans; Linoleic Acid