Abstract
Thiobarbituric acid reacting (TBAR) substances were measured in washed platelets before and after ingesting 120 mg of standardized Ginkgo biloba extract daily for 3 months, in both normo-cholesterolemic (total cholesterol, 160 ± 27 mg/dl; age, 40 ± 13 years; n = 18) and hypercholesterolemic subjects (total cholesterol, 229 ± 35; age, 45 ± 8 years; n = 12). Ginkgo biloba extract significantly reduced cellular content of TBAR substances; 42 ±21 vs. 28± 16 pmol/107 platelets (p < 0.0025) and 50 ± 17 vs. 29 ± 13 pmol/107 platelets (p < 0.004), for the normo- and hypercholemic subjects, respectively. In conclusion, Ginkgo biloba extract is a potent antioxidant in both groups, reducing TBAR substances possibly by inhibiting platelet COX-1 isoform activity.