ENHANCED PRODUCTION OF IGE AND IGG ANTIBODIES ASSOCIATED WITH A DIET ENRICHED IN EICOSAPENTAENOIC ACID

  • 1 January 1982
    • journal article
    • research article
    • Vol. 46  (4) , 819-826
Abstract
Eicosapentaenoic acid (EPA), a polyunsaturated fatty acid analog of arachidonic acids, alters certain platelet functions controlled by prostaglandins and thromboxanes, probably by inhibiting the synthesis of these molecules from arachidonic acid. The effects of a diet enriched in EPA (fish-fat diet, FFD) compared with a diet lacking EPA (beef-fat diet, BFD) upon certain immunological and inflammatory responses in outbred Sprague Dawley rats are reported. Induction of antibody formation to egg albumin (EA) produced 4- to 8-fold greater titers of IgE (P < 0.02) and IgG (P < 0.03) anti-EA antibodies in FFD rats vs. BFD rats. FFD rats had heightened active cutaneous anaphylaxis to EA, responding to a median [EA] of 10-4 mg/ml, vs. 10-3 mg/ml in BFD rats (P < 0.0032). Active Arthus reaction to EA in FFD rats was elicited to a [EA] of 10-3 g/ml vs. 10-1 g/ml in BFD rats (P < 0.01). Passive inflammatory reactions, as evaluated by passive cutaneous anaphylaxis elicited with IgE antibody, and by the intradermal injection of aggregated IgG, were not significantly different between the 2 groups. EPA constituted 7.3% of fatty acid in the livers of FFD rats, vs. 0.3% in BFD rats (P < 0.01). Enhanced levels of IgE and IgG antibody were demonstrated in FFD rats, with subsequent increased active inflammatory reactivity in these animals. The alterations may be secondary to enrichment of tissue lipids with EPA, although effects due to changes in other fatty acids were not excluded.