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Ginkgo biloba: An Ancient Tree for an Aging Society


Ginkgo biloba belongs to the botanical family of Ginkgoceae consisting of approximately 15 genera. The ginkgo tree, known to be among the oldest living species on this planet, has flourished in forests for more than 200 million years, hence it is called a “living fossil”. The modern-day Ginkgo biloba has a very distinct appearance characterized by its fan-shaped leaves. They also live a very, very long time. A single Ginkgo biloba tree might drop its distinct fan-shaped leaves every year for centuries, if not millennia. As a ginkgo ages, it does not just survive, it thrives. Though 600-year-old ginkgos grow thinner annual rings, they are likely to pump out just as much defensive and immune-supporting chemicals as their younger relatives.


This tree having survived millions of years has developed a unique adaptability to thrive in even extremely polluted environments. This attribute has made the male ginkgos very popular in air polluted cities. Its resistance, adaptability and regenerative strength, is unsurpassed in the plant kingdom and it imparts this adaptogen quality to its user. Thus, it is medicinally considered an adaptogen remedy. It is a dioecious tree with the male and female reproductive organs on separate trees. The name ginkgo comes from the Chinese words sankyo or yinkuo, which means a hill apricot or silver fruit, due to their apricot shaped mature fruits and yellow color.


Phytotherapeutic Properties and Uses


Both the leaves and the nuts of this tree have been in use for the past several centuries in traditional Chinese medicine. In fact, the nuts are known to have a longer history of usage, being first mentioned in herbals in the Yuan dynasty [1280 to 1368 AD], published in 1350 AD.1 Thus, for over 5000 years, the seeds (nuts) have been used to treat pulmonary disorders (like asthma, cough, and enuresis), and bladder inflammation, while the leaves have been mainly used to treat heart and lung dysfunctions and skin infections.2, 3 However, it was only in the last 30 to 50 years that the use of the ginkgo leaf and its standardized extracts have been used for cognitive ailments.4, 5, 6, 7, 8


According to The German Commission E (a scientific advisory board of the Federal Institute for Drugs and Medical Devices), Ginkgo B. has three primary uses or indications:


(1) For symptomatic treatment of disturbed performance in organic brain syndrome within the regimen of a therapeutic concept in cases of dementia syndromes with the following principal symptoms: memory deficits, disturbances in concentration, depressive emotional condition, dizziness, tinnitus, and headache. The primary target groups are dementia syndromes, including primary degenerative dementia, vascular dementia, and mixed forms of both.


(2) Improvement of pain-free walking distance in peripheral arterial occlusive disease in Stage II of Fontaine (intermittent claudication) and in a regimen of physical therapeutic measures, particularly walking.


(3) Vertigo and tinnitus (ringing in the ear) of vascular and involutional origin.


Studies have also shown positive results from the use of ginkgo for the following conditions: sexual dysfunction secondary to the use of selective serotonin reuptake inhibitors9 , mountain sickness and decreasing vasoactive response to cold10, macular degeneration11, asthma12, and hypoxia.13


The World Health Organization reiterated The Commission E approved uses noted above adding the following specific conditions to peripheral arterial occlusive disease: Raynaud’s disease, acrocyanosis, and post phlebitis syndrome.14



Physiological Mechanisms


The mechanism of action of ginkgo is believed to be produced by its functions as a neuroprotective agent, an antioxidant, a free-radical scavenger, a membrane stabilizer, and an inhibitor of platelet-activating factor via the terpene ginkgolide B.15, 16, 17, 18 Other pharmacologic effects include the following: endothelium relaxation mediated by inhibition of 3',5'-cyclic GMP (guanosine monophosphate) phosphodiesterase; inhibition of age-related loss of muscarinergic cholinoceptors and α-adrenoceptors; and stimulation of choline uptake in the hippocampus.19 Ginkgo extract also has been shown to inhibit beta-amyloid deposition, thus suggested in Alzheimer’s disease.20, 21, 22, 23


Chemistry and Pharmacology of Ginkgo biloba leaf

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