The effect of Ginkgo biloba (EGb 761) on arteriosclerotic nanoplaque formation and size in a long-term clinical trial

Utilizing the isolated lipoprotein receptor syndecan (heparan/chondroitin sulfate proteoglycan, HS/CS-PG) from arterial endothelium and smooth muscle cell membranes and coating therewith a silica surface, we were able to observe the very earliest stages of arteriosclerotic plaque development, the so-called nanoplaque build-up, by ellipsometric techniques (patent EP 0 946 876). The arteriosclerotic nanoplaque is represented by the ternary aggregational complex of the HS-PG receptor, lipoprotein particles and calcium ions. The model was validated in several clinical studies [1,2] on cardiovascular high-risk patients applying their blood lipoprotein fractions and, among others, proved the inhibiting effect of Ginkgo biloba on nanoplaque formation. In eight high-risk patients who had undergone an aortocoronary bypass operation, the reduction of arteriosclerotic nanoplaque formation amounted to 11.9 ± 2.5% (p ≤ 0.0078, non-parametric Wilcoxon-test for paired samples; median 10.6%) and of nanoplaque size to 24.4 ± 8.1% (p ≤ 0.0234, non-parametric Wilcoxon-test for paired samples; median 20.4%), respectively, in normal blood substitute solution with 2.5 mmol/l [Ca2+] after a 2 month therapy with 2 × 120 mg Ginkgo biloba extract (EGb 761, Rökan® novo). Additionally, we could directly demonstrate and confirm the antioxidative capacity of ginkgo and its oxygen free radical scavenging effect by disclosing an upregulation of superoxide dismutase (SOD) activity of 15.7 ± 7.0% (p ≤ 0.0391, non-parametric Wilcoxon-test for paired samples; median 16.2%) and a lowering of the quotient oxLDL/LDL by 17.0 ± 5.5% (p ≤ 0.0234, non-parametric Wilcoxontest for paired samples; median 16.9%) after the 2 month medication regimen. Furthermore, we measured a significant *Corresponding author. Presented at the International Congress on Membranes and Membrane Processes (ICOM), Seoul, Korea, 21–26 August 2005. 0011-9164/06/$– See front matter © 2006 Elsevier B.V. All rights reserved