Topical application for treatment of atopic dermatitis with flavononol galloyl glycoside from the leaves of Acer ginnala in NC/Nga mice

Acer ginnala (Korean maple) have been used as folk medicine for eye diseases related to inflammatory and infection. As part of our continuing research for new anti-atopic natural products based on their traditional therapeutic usages, we isolated several components and evaluated their anti-atopic activities in vivo. Activity guided isolation of 80% methanol extract from the leaves of Acer ginnala (AGL) yielded two flavononol galloyl glycosides and three unusual gallotannins including a new component (2,4,6-trigalloyl-1,5-anhydroglucitol). In order to evaluate anti-atopic activities, 80% methanol extract from the AGL and quercetin 3-O-(2“-galloyl)-α-L-rhamnopyranoside, which was the main compound of the AGL, were applied to atopic dermatitis-like skin lesion in Nc/Nga mice which have recently been recognized to be a model for atopic dermatitis [1,2]. As a result, clinical skin severity score decreased by the treatment of them. They also lowered eosinophils, IgE and Th2 cytokines levels in serum, significantly (p<0.05). In addition, both COX-2 and iNOS in mouse skin tissues and their mRNA expressions were suppressed by them, significantly (p<0.05). These results demonstrate that AGL and its main component, quercetin 3-O-(2″-galloyl)-α-L-rhamnopyranoside may be useful for treatment to skin allergies as a novel immunomodulator.

References: 1. Simon, D. et al. (2004) Allergy. 59:561–570.

2. Thepen, T. et al. (2006)J. Allergy. Clin. Immunol. 97: 828–837.