From the Manufacturer:
Grapine, High-Potency is an optimal blend of the powerful antioxidant proanthocyanidins derived from grape seeds and maritime pine bark. Numerous scientific studies suggest that proanthocyanidins have health benefits, which include capillary-strengthening properties and offsetting cell-damaging free radicals.
Grapine’s proanthocyanidins help protect vital nerve tissue from oxidative damage. They are among the most powerful antioxidants found in nature. Antioxidants help to neutralize free radicals—highly active molecules that cause cell damage.