Preventive Effects of (-)-Epigallocatechin-3-O-gallate on Mouse Type IV Allergy Induced by Oxazolone and its Antiinflammatory Activities

Abstract

Abstract We investigated the mechanisms underlying the inhibitory effects of (-)-epigallocatechin-3-O-gallate (EGCG) on oxazolone-induced type IV allergy in male ICR mice and two simple inflammation mouse models. Serum levels of interleukin-12 (IL-12) and γ-interferon (γ-IFN) were significantly increased in mice with severe ear edema induced by type IV allergy in comparison with normal mice. The oral administration of EGCG at a dose of 50 mg/kg body weight prevented the elevations of these levels. Lowering of serum levels of IL-2, spleen natural killer NK cell activity and serum antioxidant activity in mice with allergic symptoms were also prevented by oral administration of EGCG. Furthermore, the oral administration of EGCG at the same dose prevented mouse ear edema induced by arachidonic acid and tended to prevent mouse ear edema induced by croton oil. These results suggested that the antiallergic mechanism of action of EGCG involves inhibition of the fluctuations in cytokines and chemical mediators, and maintenance of antioxidant status in allergic mice