Treatment of Ginkgo biloba polysaccharide before focal ischemia/reperfusion injury decreased cerebral infarct size and improved neurological deficits in rats, and the neuroprotective effects were mediated by suppression of NO production, decreased concentrations of TNF-α and IL-1β, increased concentration of IL-10, and inhibition of oxidative stress as evidenced by increased SOD activity and decreased MDA level. This evidence concerns the gene SOD1 and brain infarction.