Quercitrin, the Main Compound in <i>Wikstroemia indica</i>, Mitigates Skin Lesions in a Mouse Model of 2,4‐Dinitrochlorobenzene‐Induced Contact Hypersensitivity
Jonghwan Jegal, No-June Park, So‐Yeon Lee, Beom-Geun Jo, Sim-Kyu Bong, Su‐Nam Kim, Min Hye Yang
Abstract
Hapten‐induced contact hypersensitivity (CHS) is widely utilized to induce immune activation in animal models of allergic contact dermatitis. Our previous findings suggested that the 95% EtOH extract of Wikstroemia indica (L.) C. A. Mey. has antiallergic and anti‐inflammatory effects in DNCB‐treated CHS SKH‐1 hairless mice. The aim of this study was to evaluate the protective effects of compounds isolated from the EtOAc fraction of W. indica in RBL‐2H3 cells and 2,4‐dinitrochlorobenzene‐ (DNCB‐) induced CHS mice. Of eight compounds in W. indica , that is, umbelliferone, daphnoretin, wikstrocoumarin, (+)‐syringaresinol, tricin, (+)‐lariciresinol, erythro ‐guaiacylglycerol‐ β ‐coniferyl ether, and quercitrin, quercitrin exhibited the most antiallergic activity against antigen‐induced β ‐hexosaminidase release and IL‐4 mRNA expression, which are markers of degranulation in RBL‐2H3 cells. After a 7‐sensitizing period, 14 days of DNCB treatment with or without topical pimecrolimus (1%) or quercitrin (0.5%) treatment, quercitrin was found to suppress DNCB‐induced increases in serum IL‐4 and IgE concentrations and transepidermal water loss. These results indicate that quercitrin has therapeutic potential for treatment of allergies and allergy‐related contact dermatitis.