title: A double-blind, randomized, placebo-controlled trial of n-3 versus n-6 fatty acid-based lipid infusion in atopic dermatitis.
abstract: BACKGROUND
  In the involved epidermis of patients with atopic dermatitis, changes in the metabolism of eicosanoids with increased quantities of the arachidonic acid (AA)-derived lipoxygenase products have been observed. Free eicosapentaenoic acid (EPA), a fish oil-derived alternative (n-3) fatty acid, may compete with AA, resulting in an anti-inflammatory effect.
  
  
  METHODS
  In a 10-day double-blind, randomized, placebo-controlled trial, 22 patients hospitalized for moderate-to-severe atopic dermatitis were randomly assigned to receive daily infusions of either a n-3 fatty acid-based lipid emulsion (fish oil, 10%; 200 mL/d) or a conventional n-6-lipid emulsion (soybean oil, 10%; 200 mL/d). Topical treatment was restricted to emollients. The severity of disease was evaluated daily with scoring of erythema, infiltration, and desquamation and by subjective patient scoring of clinical manifestations. In addition, plasma-free and total-bound fatty acids and the composition of membrane fatty acids in blood cells (thrombocytes, granulocytes, and erythrocytes), lipid mediators from isolated neutrophils and platelets, and lymphocyte-activation parameters were determined.
  
  
  RESULTS
  Twenty patients completed the trial. Marked improvement from baseline was seen in both groups. On days 6, 7, 8, and 10, disease severity score-defined as the sum of all scores-was more pronounced (p < .05) in the n-3 group compared with the n-6 group. Free arachidonic acid in plasma did not change substantially in both groups, whereas plasma-free EPA, total-bound EPA, and the membrane EPA/AA ratio markedly increased in response to n-3-lipid infusion. In parallel, EPA-derived lipid mediators appeared, whereas lymphocyte functions were unaffected. In the post-treatment period (2/4 weeks), relapse was observed in some patients after n-3 psoralene-ultraviolet A (PUVA) infusion, whereas there was a marked long-term improvement in the n-6 group.
  
  
  CONCLUSIONS
  IV n-3-fatty acid administration is effective in acutely improving the severity of atopic dermatitis, paralleled by changes in plasma and membrane fatty acid composition and lipid mediator synthesis. The long-term beneficial effects of IV n-6 fatty acids should be evaluated further.
authors: Department of Dermatology, Center for Dermatology and Andrology, Justus-Liebig-University, Giessen, Germany. Peter.Mayser@derma.med.uni-giessen.de
authors: Peter
authors: P
authors: Mayser
authors: Konstantin
authors: K
authors: Mayer
authors: Mojgan
authors: M
authors: Mahloudjian
authors: Steffen
authors: S
authors: Benzing
authors: Hans-Joachim
authors: HJ
authors: Krämer
authors: Wolf-Bernhard
authors: WB
authors: Schill
authors: Werner
authors: W
authors: Seeger
authors: Friedrich
authors: F
authors: Grimminger
mesh_terms: D000293:Adolescent; D000328:Adult; D001095:Arachidonic Acids / Q000097:blood; D003876:Dermatitis, Atopic / Q000628:therapy*; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000097:blood; D005217:Fat Emulsions, Intravenous / Q000008:administration & dosage / Q000627:therapeutic use; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage / Q000627:therapeutic use*; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007263:Infusions, Parenteral; D007700:Kinetics; D008297:Male; D012720:Severity of Illness Index
chemical_list: D001095:Arachidonic Acids; D005217:Fat Emulsions, Intravenous; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D015118:Eicosapentaenoic Acid