In vivo supplementation with Ginkgo biloba protects membranes against lipid peroxidation

The effect of Ginkgo biloba (Gb) supplementation in vivo was studied on lipid peroxidation of microsomal membranes. Administration of up to 100 mg/kg/day Gb to rats did not significantly affect either the activity of microsomal enzymes, the rate of generation of superoxide anion or the iron reduction rate by rat liver microsomes. Lipid peroxidation, assessed by the generation of lipid radicals measured by electron paramagnetic resonance (EPR) spectroscopy using POBN as the spin trap, was reduced by 39.7% and thiobarbituric acid reactive substances (TBARS) generation by 30% after Gb supplementation (100 mg/kg/day) for 10 days. Moreover, membranes from Gb treated animals showed a significant lower content of lipid radicals and TBARS after exposure to oxidative stress both in vitro (t-butyl hydroperoxide) and in vivo (acute iron overload). The data presented here showed that Gb extracts were able to limit lipid peroxidation and scavenge lipid radicals in vivo and actively protect membranes from oxidative damage.