HerbalGram Issues Issue #34 Effects of Ginkgo biloba Extract (EGb 761) on the Central Nervous System: Ginkgo biloba (EGb 761) as a Free-Radical Scavenger.
Effects of Ginkgo biloba Extract (EGb 761) on the Central Nervous System: Ginkgo biloba (EGb 761) as a Free-Radical Scavenger.
Edited by C. Ferrandini, M. T. Droy-Lefaix, Y. Christen. 1993. Elsevier, Paris. $30. Softcover, 186 pp. ISBN 2-906077-36-4. Available from ABC Books, Item #B016B. These two reference books represent the first two volumes of an ongoing series entitled "Advances in Ginkgo biloba Extract Research." Derived from the proceedings of annual symposiums on Ginkgo biloba Extract (EGb 761), these textbooks serve to reinforce EGb 761's standing as the most extensively researched Ginkgo extract in the world and most frequently prescribed phytomedicine in Europe. Developed and manufactured by Willmar Schwabe GMBH of Karlsruhe, Germany, EGb 761 is a concentrated and purified preparation of Ginkgo leaves standardized to contain 24% ginkgo flavone glycosides and 6% terpene lactones. The first book, Effects of Ginkgo biloba Extract (EGb 761) on the Central Nervous System, is taken from the proceedings of the International Symposium held in Montreux, Switzerland on April 20, 1991. The articles serve to expand the understanding of EGb 761's effect on the Central Nervous System (CNS). Early research on EGb 761 largely focused on its vasoregulatory and antioxidant capabilities in the CNS. This text explores the terpene lactones (specifically the ginkgolides) and platelet-activating factor (PAF) inhibition. Anti-PAF activity, in addition to the above-mentioned actions, has led to a great deal of focus on EGb 761's ability to counteract the effects of ischemia-reperfusion (ability to counteract the effects of lack of oxygenation ttissue which may lead to free radical damage). This has pointed to it as a potential therapeutic tool in recovery from strokes. Added to this is recent research indicating that another terpene lactone, bilobalide, has neuroprotective pro perties. One of the more intriguing areas explored in this book is the potential for EGb 761 in traumatic brain injury. Drs. D. G. Stein and S. W. Hoffman of Rutgers University present the findings of an animal study demonstrating EGb 761's ability to enhance recovery and learning in rats with bilateral injury to the frontal cortex. The clinical potential for head injury patients is certainly staggering and should become the focal point of future clinical trials with EGb 761. Another report also extends this protective effect to visual pathways in the CNS. Three animal studies examine the effect of EGb 761 on learning deficits associated with aging. This section of the book cumulates in a review article on the effects of EGb 761 on normal or altered memory function in humans. It is interesting to note that a great deal of clinical research focus with EGb 761 has been in the areas of resistant depression associated with cerebrovascular insufficiency and early senile dementia (please see review on treatment of early-stage Alzheimer's Disease in this issue of Herbal Gram). These studies and the entirety of this text add fuel to the growing potential of EGb 761 as a leading therapeutic tool in bath the prevention and early intervention of CNS disorders associated with aging. Volume 2 of the series on ginkgo research, Ginkgo biloba (EGb 761 )as a Free-Radical Scavenger, is taken from the Proceedings of the International Symposium held in Budapest, Hungary on June 12, 1992. This textbook further establishes EGb 761 as an effective antioxidant in the CNS, retina, and cardiovascular systems. Although largely dedicated to animal studies, the middle section of this textbook deals with EGb 761's ability to serve as a powerful antioxidant for visual structures including the retina. Previous research has suggested that EGb 761 may serve as both a preventive and early therapeutic tool for macular degeneration. The studies in this text focus largely on the retina and the role that EGb 761 may play in management of retinopathy. One study, partly completed at the Schnepens Eye Research Institute and Harvard Medical School in Boston, indicates that dally treatment with EGb 761 reduces the incidence of neovascularization in an animal model of retinopathy of prematurity. This condition occurs in premature infants as a result of high oxygen therapy necessary for life support and is due to the production of free radicals in the retina. Other articles focusing on retinal physiology indicate that EGb 761's PAF-antagonistic properties add to its ability to protect retinal damage. Combined with the extract's vasoregulatory and neuroprotective properties, this makes EGb 761 a potentially useful tool in the long-term management of diabetes and prevention of retinopathy and neuropathy in these individuals. Two final areas of interest in this textbook re EGb 761's protection of red blood cells and the heart muscle from oxidative damage. These findings make EGb 761 a viable alternative for individuals recovering from myocardial infarction as well as stroke. These two textbooks are essential reading for professionals attempting to stay current with the impressive amount of research being generated on Ginkgo biloba extracts. Volume 3 of this series, which was published in 1994, will cover EGb 761's activity on the cardiovascular system. Article copyright American Botanical Council. ~~~~~~~~ By Donald Brown">Edited by Y. Christen, J. Constentin, M. Lacour. 1992. Elsevier, Paris. $30. Softcover, 172 pp. ISBN 2-906077-28-3. Available from ABC books, Item #C:InetpubwwwrootDataB016A.p#