|
Photo copyright Steven Foster |
Common name: Maidenhair tree
Parts used and where grown: Ginkgo biloba is the world’s longest living species of tree; individual trees live as long as 1,000 years. Ginkgo grows most prominently in the southern and eastern US and in China. The leaves of the tree are used.
In what conditions might ginkgo biloba be supportive?
| • Alzheimer’s
disease
• cerebrovascular insufficiency • diabetes |
• intermittent claudication
• multiple sclerosis • tinnitus |
Historical or traditional use: Medicinal use of ginkgo can be traced back almost 5,000 years in Chinese herbal medicine. It was recommended for respiratory tract ailments as well as memory loss in the elderly.
Active constituents: The medical benefits of Ginkgo biloba extract (GBE) rely on the proper balance of two groups of active components: the ginkgo flavone glycosides and the terpene lactones. The 24% ginkgo flavone glycoside designation on GBE labels indicates the carefully measured balance of bioflavonoids. These bioflavonoids are primarily responsible for GBE’s antioxidant activity and ability to inhibit platelet aggregation (stickiness). These two actions may help GBE prevent circulatory diseases such as atherosclerosis, and support the brain and central nervous system.1
The unique terpene lactone components found in GBE, known as ginkgolides and bilobalide, increase circulation to the brain and other parts of the body as well as exert a protective effect on nerve cells. Ginkgolides may improve circulation and inhibit platelet-activating factor (PAF). Bilobalide protects the cells of the nervous system.2 Recent animal studies indicate that bilobalide may help regenerate damaged nerve cells.3
GBE and circulation: GBE increases circulation to both the brain and extremities of the body. In addition to inhibiting platelet stickiness, GBE regulates the tone and elasticity of blood vessels.4 In other words, it makes circulation more efficient. This improvement in circulation efficiency extends to both large vessels (arteries) and smaller vessels (capillaries) in the circulatory system.5
Antioxidant properties: GBE may have antioxidant properties in the brain, retina of the eye, and the cardiovascular system.6 Its antioxidant activity in the brain and central nervous system may help prevent age-related declines in brain function. GBE’s antioxidant activity in the brain is of particular interest. The brain and central nervous system are particularly susceptible to free radical attack. Free radical damage in the brain is widely accepted as being a contributing factor in many disorders associated with aging, including Alzheimer’s disease.7
Nerve protection and PAF inhibition: One of the primary protective effects of the ginkgolides are their ability to inhibit a substance known as platelet-activating factor (PAF).8 PAF is a mediator released from cells that causes platelets to aggregate (clump together). High amounts of PAF are associated with damage to nerve cells, poor blood flow to the central nervous system, inflammatory conditions, and bronchial constriction.9 Much like free radicals, higher PAF levels are also associated with aging.10 Ginkgolides and bilobalide protect nerve cells in the central nervous system from damage during periods of ischemia (lack of oxygen to tissues in the body).11 This effect may be supportive for persons who have suffered a stroke.
How much should I take? Many people take 120-160 mg of GBE, standardized to contain 6% terpene lactones and 24% flavone glycosides, two to three times per day. Amounts up to 240 mg per day are used by some people with cerebrovascular insufficiency, confusion and memory loss, and resistant depression. GBE may need to be taken for six to eight weeks before desired effects are noticed. Ginkgo may also be taken as a tincture of 0.5 ml three times daily.
Are there any side effects or interactions? Ginkgo biloba extract is essentially devoid of any serious side effects. Mild headaches lasting for a day or two and mild upset stomach have been reported in a very small percentage of people using GBE. There are no known contraindications to the use of GBE by pregnant and lactating women.
It is important to remember that circulatory conditions in the elderly can involve serious disease. Individuals should seek proper medical care and accurate medical diagnosis prior to self-prescribing GBE.
References:
1. Drieu K. Preparation and definition of Ginkgo biloba
extract. In: Rokan (Ginkgo biloba): Recent Results in Pharmacology and Clinic, ed.
EW Fünfgeld. Berlin: Springer-Verlag, 32-6.
2. Krieglstein J. Neuroprotective properties of Ginkgo
biloba—constituents. Zeitschrift Phytother 1994; 15:92-6.
3. Bruno C, Cuppini R, et al. Regeneration of motor
nerves in bilobalide-treated rats. Planta Medica 1993; 59:302-7.
4. Clostre F. From the body to the cellular
membranes: the different levels of pharmacological action of Ginkgo biloba extract.
In: Rokan (Ginkgo biloba): Recent Reseults in Phamacology and Clinic, ed .
EW Fünfgeld. Berlin: Springer-Verlag, 1988, 180-98.
5. Jung F, Mrowietz C, et al. Effect of Ginkgo
biloba on fluidity of blood and peripheral microcirculation in volunteers. Arzneim-Forsch
Drug Res 1990; 40:589-93.
6. Ferrandini C, Droy-Lefaix MT, Christen Y, eds. Ginkgo
biloba Extract (EGb 761) as a Free Radical Scavenger. Paris: Elsevier, 1993.
7. Harman D. Free radical theory of aging: a
hypothesis on pathogenesis of senile dementia of the Alzheimer’s type. Age
1993; 16:23-30.
8. Lamant V, Mauco G, et al. Inhibition of the
metabolism of platelet activating factor (PAF-acether) by three specific antagonists from Ginkgo
biloba . Biochem Pharmacol 1987; 36: 2749-52.
9 Kroegel C. The potential pathophysiological role
of platelet-activating factor in human disease. Klin Wochenschr 1988; 66: 373-8.
10. Kroegel C, Kortsik C, et al. The
pathophysiological role and therapeutic implications of platelet activating factor in
diseases of aging. Drugs Aging 1992; 2:345-55.
11. Krieglstein J. Neuroprotective properties of Ginkgo
biloba—constituents. Zeitschrift Phytother 1994; 15:92-6.
Copyright © 1998 Virtual Health, LLC
It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. For many of the conditions discussed, treatment with prescription or over-the-counter medication is also available. Consult your physician, nutritionally-oriented health care practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.The information presented in HealthNotes Online is for informational purposes only.