Cellular protection from oxidative stress by the blood orange pigment cyanidin-3-O-beta-glucopyranoside

The cyanidin-3-O--glucopyranoside (C-3-G) antioxidant effects were assessed in two models of increased oxidative stress. Isolated post-ischemic rat heart reperfused with C-3-G showed inhibition of malondialdehyde (MDA) formation (-67% and -94% in 10 and 30 M C-3-G-reperfused hearts, respectively) and improved energy metabolism. Normoxic hearts perfused in the recirculating Langendorff mode with 10 and 30 M C-3-G indicated that C-3-G can permeate within myocardial cells. Dose-dependent decrease of MDA generation by C-3-G was observed in 2 mM H2O2-treated human erythrocytes (apparent IC50 of 5.12 M and 38.43 M were calculated for C-3-G and resveratrol, respectively). In conclusion, C-3-G (largely present also in pigmented oranges) may have beneficial effects in case of increased oxidative stress.