Inhibition of Chronic Skin Inflammation by Topical Anti-inflammatory Flavonoid Preparation, Ato $Formula^{\circledR}$

Flavonoids are known as natural anti-inflammatory agents. In this investigation, an anti-inflammatory potential of new topical preparation (SK Ato $Formula^{\circledR}$) containing flavonoid mixtures from Scutellaria baicalensis Georgi roots and Ginkgo biloba L. leaves with an extract of Gentiana scabra Bunge roots was evaluated in an animal model of chronic skin inflammation. Multiple 12-O-tetradecanoylphorbol-13-acetate treatments for 7 consecutive days on ICR mouse ear provoked a chronic type of skin inflammation: dermal edema, epidermal hyperplasia and infiltration of inflammatory cells. When topically applied in this model, this row formulation $(5-20\;{\mu}L/ear/treatment)$ reduced these responses. Furthermore, it inhibited prostaglandin $E_2$ generation (17.1-33.3%) and suppressed the expression of proinflammatory genes, cyclooxygenase-2 and $interleulin-1{\beta}$ in the skin lesion. Although the potency of inhibition was lower than that of prednisolone, all these results suggest that Ato $Formula^{\circledR}$ may be beneficial for treating chronic skin inflammatory disorders such as atopic dermatitis.