Structure-Activity Relationship of Immunoregulatory Factors in Foodstuffs.

Abstract

The structure-activity relationship of allergy enhancing and suppressing factors in foodstuffs was summarized in this text. Polyunsaturated fatty acids (PUFA) enhance allergic response by enhancing IgE production and by suppressing production of other antibodies in rat lymphocytes. Because the expression of IgE production enhancing activity was inhibited by lipophilic antioxidants, lipid oxidation reaction seems to have participated in the activity. Xanthene dyes, a group of synthetic dyes, also exert IgE production enhancing effect, and the activity is dependent on the degree of halogenation. On the other hand, PUFA exert anti-allergic effect by suppressing the release of chemical mediators from rat peritoneal exudate cells, and the activity becomes stronger with the increase in the number of double bonds. In addition, antioxidants such as tea polyphenols (TP) and flavonoids exert anti-allergic effect mainly due to the suppression of chemical mediator release. Histamine release suppressing activity is observed in triphenol derivatives, but not in diphenols. On the contrary, LTB4 release suppressing activity is observed in mono and diphenolic derivatives with antioxidative activity. These results suggest that various food components have immunoregulatory activity and that optimization of their intake is desirable.