Protective Effect of Grape Seed Procyanidins against H2 O2 -Induced Oxidative Stress in PC-12 Neuroblastoma Cells: Structure-Activity Relationships.

ABSTRACT

To establish a structure-activity relationship for procyanidins, we verified the cyto-protective effect of 13 grape seed procyanidins, ranging from monomers to trimers against H2 O2 -induced oxidative stress in PC-12 neuroblastoma cells. Our study demonstrated some procyanidins were able to significantly protect PC-12 cells from the H2 O2 -induced cytotoxicity suggesting they possess neuroprotective effects against oxidative stress. Procyanidins' protective effects against oxidative stress mainly depended on their polymerization degree in addition to their structural features. A positive correlation was found between procyanidins' polymerization degree and the protective effect against oxidative stress in PC-12 cells. The presence of 3- or 3'-galloylated groups in the C-ring of procyanidin molecules significantly increased their protective activity as well. These results demonstrated that galloylated high-molecular-mass procyanidins would be of more interesting as promising antioxidant natural compounds. This work for the first time demonstrated the structure-activity relationships of 13 procyanidins' antioxidative stress activity, which could have a significant impact on future development of procyanidins for healthy food products or drugs to treat disease such as neurodegenerative disorders. PRACTICAL APPLICATION This work evaluated the protective effect of procyanidins against oxidative stress in PC-12 neuroblastoma cells and established their activity-structure relationships, which provides useful cellular evidence for the further investigating the structure-optimizing and function-exploiting of procyanidins.