Protective Effect of Dibenzoylmethane on Chemically- and UV Light-Induced Skin, Inflammation, Sunburn Lesions, and Skin Carcinogenesis in Mice

摘要

Dibenzoylmethane (DBM) is a minor constituent of licorice and an analogue of curcumin. We previously reported that feeding 1% DBM in the diet strongly inhibited 7,12-dimethylbenzyla[a]anthracene (DMBA)-induced mammary tumorigenesis and formation of leukemias/lymphomas in Sencar mice). In this report, we show that topical application of DBM to the backs of mice inhibited chemical- and ultraviolet light (UV)-induced inflammation, sunburn lesions, and formation of skin tumors in mice. Topical application of DBM inhibited TPA-induced edema of mouse ears and skin tumor promotion in CD-1 mice in a dose-dependent manner. Topical application of 3 - 10 μmol DBM with 5 nmol TPA twice weekly for 16 weeks in CD-1 mice previously treated with DMBA inhibited the number of skin tumors per mouse by 65 - 93%, and percent of mice with tumors was inhibited by 29 - 50%.. Topical application of 10 μmol DBM with mirex (a non-TPA type tumor promoter) 3 times a week for 18 weeks in DMBA-initiated mice inhibited the mirex-induced number of tumors per mouse by 63%. DBM also strongly inhibited UV-induced skin sunburn lesions and formation of skin tumors in SKH-1 mice. Topical application of 10 μmol DBM to SKH-1 mice previously initiated with DMBA at 10 min prior to each UV (30 mJ/cm~2) irradiation twice a week for 34 weeks inhibited the number of skin tumors per mouse by 91%. Percent of mice with skin tumors was reduced by 44%. In complete UV skin tumorigenic model, topical application of 10 umol DBM at 10 min before each UV (30 mJ/cm~2) irradiation twice weekly for 34 weeks inhibited the number of skin tumors per mouse by 96%, and percent of mice with tumors was decreased by 48%. Our results indicated that DBM strongly inhibited both chemical- and UV-induced skin inflammation, sunburn lesions and skin tumorigenesis in mice.