The anti-aging effects of cyanidin were investigated under stress-induced premature senescence (SIPS) using WI-38 human diploid fibroblasts. WI-38 cells that were treated with 300 microM H(2)O(2) showed losses of cell viability, increased lipid peroxidation, and shortened cell lifespans. However, treatment with cyanidin attenuated cellular oxidative stress through increase of cell viability and the inhibition of lipid peroxidation. In addition, the life spans of young-, middle-, and old-aged WI-38 cells were prolonged by cyanidin treatment. Furthermore, H(2)O(2)-treated WI-38 cells significantly increased mRNA and protein expressions of nuclear factor-kappaB, cyclooxygenase-2, and inducible nitric oxide synthase, while those treated with cyanidin had significantly decreased expressions. These results suggest that cyanidin may delay the aging process by attenuating oxidative stress under the SIPS cellular model.