AIM: To investigate the mechanism of Delphinidin(Dp)in protecting retinal against light induced oxidative damage.

METHODS: All 661W photosensitive cells were treated with 2 000Lx light(48h)and/or different concentrations of Dp(5, 10, 20μmol/L, 24h). Cell activity, intracellular LDH activity, TBARS content and antioxidant enzymes(SOD, GSH-Px, GST)activity were determined respectively. After the healthy SD rats were treated with 3 000 Lx light(24h)and/or Dp \〖100mg/(kg·d)for 4wk\〗, then changes in retinal tissue structure were observed and fluctuations in oxidative stress index(SOD, GSH-Px, GST)were determined.

RESULTS: The results of in vitro experiments showed that the cell activity was significantly decreased after irradiation, the LDH activity and TBARS content were increased, and the activity of antioxidant enzyme system were decreased. However, Dp treatment could increase cell viability, decrease LDH activity and TBARS content, and increase the activity of antioxidant enzyme system. In vivo experiments showed that Dp can protect the structural integrity of retina, reduce the content of TBARS in retinal tissue, and increase the activity of SOD, GSH-Px and GST.

CONCLUSION: Dp may protect retinal against Photochemical factors -induced oxidative damage by regulating the oxidation-antioxidant system.