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

Unlabelled: 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 H O -induced oxidative stress in PC-12 neuroblastoma cells. Our study demonstrated some procyanidins were able to significantly protect PC-12 cells from the H O -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.