Ginkgo biloba Lindsay Newcomb Jamie Swank Andrew Soteres History and Background Ancient use in China and Japan as a tonic. – Poor Circulation – Inner ear disorders – Absent-mindedness, Dementia, Depression, and Hypertension in the elderly – Impotence in men Chinese used leaves and nuts Use dates back over 5000 years About the plant… Commonly known as maidenhair tree Known for its green, fan- shaped leaves that turn yellow in autumn Unique seeds (not used in extracts) Extracts prepared from dried, green, whole leaves Tree can reach up to 80 feet tall and 60 feet wide in urban areas Characteristics Dioecious – separate male and female trees Only female trees produce fruit Grows in moderate and sub-tropical climates Gametophyte and embryo are edible while surface oils can cause dermatitis About the plant…(cont’d) The Chinese call it Duck Foot or Silver Apricot Ginkgo family is nearly free of disease and pests A Living Fossil The world’s oldest tree In existence for over 250 million years Darwin referred to it as “a living fossil” Present Usage Uses in Medicine – Age-associated memory impairment (AAMI), dementia and Alzheimer's. – Peripheral arterial occlusive disease Structures Phenolic Substituents Terpene Substituents Physiologic Mode of Action Attributed to a combination of the flavonoid glycosides and the diterpene lactones (ginkgolides). Physiologic Mode of Action Cont’d Acts by releasing vasodilators, specifically nitric oxide and PGI2, which allows increased blood flow throughout the circulatory system and therefore increase oxygen and nutrient delivery to the tissues. Allows increased microcirculation in the capillaries (i.e. better exchange on the cellular level) Decreases blood viscosity Molecular Mode of Action Treatment with ginkgo increases the production of NO (nitric oxide) through NOS (nitric oxide synthase). NO increases the activity of KCa channels and invokes the influx of Ca2+ into endothelial cells. This mode was double checked against a known Ca2+ channel blocker (TEA) and inhibited the effects of ginkgo. Ginkgo does not affect ATP K+ channels. Ginkgo and Memory Effects on AAMI and cerebral insufficiency All but 1 of the 8 studies found a reduction in the symptoms of these diseases. May take 4-6 weeks to see improvement. UCLA study Peripheral Arterial Disease Intermittent Claudication (IC) One study showed that patients on ginkgo extract therapy had increased pain- free walking distance. Another study showed that there was a reduction in pain at rest with patients on ginkgo therapy. Other Positive Effects of Ginkgo Improvements in cerebral metabolism (increases the efficiency of the oxygen that’s present) Increase in the release of neurotransmitters Antioxidant activity Prevention of free radical damage Side effects Few and far between. The 5 reported cases have included hemorrhage, hematoma (rupture of blood vessels), and hyphema (bleeding in eye). In all trials <0.5% reported minor side effects including headaches, GI distress and allergic skin reactions. Overall, ginkgo is relatively safe. Newest Research Ginkgo as an anti- cancer agent – In vitro exposure of human breast cancer and bladder cancer cells to ginkgo extract – Possible reasons Ginkgo in treatment of diabetes – Treatment of diabetes symptoms (similar to its effects on the vascular system) – Role of platelet- activating factor (PAF) Conclusion Although not a cure-all, the evidence suggests that ginkgo can increase memory capabilities in those with AAMI and decrease the effects of peripheral arterial disease. Further studies will be needed to assess the efficacy of ginkgo as regards cancer and diabetes. Ginkgo biloba This leaf from a tree in the East, Has been given to my garden. It reveals a certain secret, Which pleases me and thoughtful people. Does it represent One living creature Which has divided itself? Or are these Two, which have decided, That they should be as One? To reply to such a Question, I found the right answer: Do you notice in my songs and verses That I am One and Two? -Johann Wolfgang von Goethe Questions?!?!?