Suppression of Hydrogen Peroxide-Induced Cytotoxicity toward Chinese Hamster Lung Fibroblasts by Chemically Modified Curcumin

We assessed the inhibitory effects of curcumin and its chemically modified homologues against H2O2-induced cytotoxicity toward Chinese hamster lung fibroblasts V79 cells with a colony formation assay. Among 4 curcuminoids, dihydroxycurcumin and dihydroxytetrahydrocurcumin suppressed H2O2-induced cytotoxicity. On the contrary, neither curcumin nor tetrahydrocurcumin showed any suppressive effects. These results support our empirical rule that the o-dihydroxy (catechol) moiety is essential for the inhibitory effects.