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AUGUST/SEPTEMBER 2001 - Ginkgo - Ginkgo biloba
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Ginkgo biloba...Timeline… Born …more than 270 million years ago
Life Span …more than 3000 years
Disappeared …7 million years ago in North America
…2.5million years ago in Europe
Re-discovered …1691 in Japan by Englebert Kaempfer and replanted in the West
Keeping the Plants Alive is written by Isla Burgess. The Photos are by Jenny Grinlington.
The old ways…
What more can be said about:
a tree who is the subject of poems, song, drawings, paintings, crests and emblems
a tree whose sperm ‘swim'
a tree who survived the Nuclear bomb on Nagasaki, August 6th 1945
a tree who survived the great fire of Tokyo in 1923 and protected a temple in its midst from fire
a tree who is the subject of many books and has a beautiful website to itself at www.xs4all.nl/~kwanten/history.htm
a tree who graces temple grounds and shrines and is devoutly worshipped
a tree that is resistant to diseases, insects, air pollution, fire and radioactive radiation
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?
Goethe 1819
This ‘living fossil' is all of this and more.
Thousands of dollars change hands daily as it becomes a part of the ‘currency' of health and healing, thousands of words are spoken and written as its uses are evaluated. It is an example we are told of how we can get more for less where 50 parts of the herb are represented by one part. That is 50 kg of leaf in 1kg of extract. Are there 50 leaves in a tablet?
Read On…
It was the seed that was mostly used in Traditional Chinese Medicine and it is thought that the Japanese use originated there.
A sixteenth century Chinese text, translated by Dr. C.A. Stuart and Dr. F. Porter Smith in 1911 in their book called ‘Chinese Medicinal Herbs', lists the medicinal uses as being beneficial in the treatment of asthma, coughs, bladder irritation and uterine fluxes. Anti-neoplastic properties were attributed to the raw seeds and cooked they were used as peptics, promoting digestion, and anthelmintics.
There are early references to the leaf being used medicinally, the earliest for blood circulation and lungs is said to be written in a 2800 BC Chinese Materia Medica but the original copy of this has not been found.
Other Chinese Herbals in 1436 and 1505 list skin treatment, head sores, freckles, chillblains, wound plasters, and the treatment of diarrhoea,
The new ways….
Ginkgolides were first isolated in 1932 but in the west the medicinal uses were not studied until the 1950's. Ginkgo is one of the few examples in herbal medicine where the current use has little bearing on the traditional use.
The tree is extensively cultivated and most extracts on the American market come from huge plantations of shrub sized trees owned by a German/French company in the United States and France
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What plant?
An astonishingly beautiful tree in autumn when its verdant green leaves turn brilliant yellow. I have seen cars come to an abrupt halt in the middle of a busy road at the sight.
This large spreading majestic tree with maidenhair fern-like but fan shaped leaves and nuts similar to those of an apricot but smaller, is now grown across the temperate world, in parks, along street edges and avenues. It is not known in the wild.
Catkins appear in the late spring followed by the fruit with pungent smelling flesh and a hard cored sweet and bitter nut. Ginkgo is dioecious.
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What Part and When to harvest
The leaves are the focus of current medicinal uses and are best harvested just before turning yellow.
I have always waited until the first leaves turn yellow and then harvest the green ones.
BUT Planta Medica (1992;58:413-16) reported on a study which showed that the female trees had higher active constituents than the male but all younger trees
had higher levels of ginkgolides than mature trees.
Before fruiting it is difficult to tell the sex of the tree. Some say it is the division of the lobes that gives a clue - the deeper divisions are found on the male - and the female tree loses its leaves later and has a more horizontal appearance.
The seeds have the smell of rancid butter due to the butyric acid present. The seed coat has a small amount of Ginkgolic acid which is similar to urushiol, an allergen in poison oak.
How to use?
There are many preparations available.
Mostly those sold in tablet form are standardised preparations and claimed to be of a strength of 50:1 (see earlier reference). This came about, I believe, as a result of the earlier clinical trials that were based on this strength and now this has become the guide for clinical dispensing.
The Commision E monographs state that;
"Ginkgo extract is a good example of a phytomedicine that must be standardized in order to deliver the intended benefits; the scientific literature does not support the clinical benefits of other dosage forms of crude
ginkgo leaf or low-concentration extracts made from the leaf." 3 They give no reference to the scientific literature on which these claims are based.
Medical herbalists use alcoholic extracts and these are also often standardised to 24% flavone glycosides, one group of active constituents.
I had an older student who added some of the ground up leaf to her breakfast each morning with no ill effects, and another who developed stomach pains when powdered ginkgo was added to her anti-oxidant powder but had no affect from the alcoholic extract.
Traditional uses in China (there is no history of its use in Western Herbal medicine).
Seeds have been used for many conditions associated with the respiratory system including; asthma, bronchitis, wheezing and coughs.
Other uses for the seed include;
bladder irritation
urinary frequency
uterine fluxes
anti-neoplastic (raw seeds)
promoting digestion (cooked seed)
anthelmintics (cooked seed)
stabilize sperm production (cooked seed)
And for the leaves;
blood circulation
lungs
skin treatment
head sores
freckles
chillblains
wound plasters
diarrhoea
Many sources say that there was no traditional use of the leaves yet this appears to be reasonably well documented!
Current uses
In China
Leaves according to ‘The Ginkgo Pages',40 are used in Chinese Medicine to treat people with;
asthma
bronchitis
hearing loss
memory loss
poor circulation
angina
high blood pressure
anxiety
chillblains
wound plasters
diarrhoea
In the West (largely based on the strength of the research);
A range of conditions associated with the circulatory system including;
cerebral insufficiency in people who do not have dementia or strokes, that results in poor concentration and memory, confusion, anxiety, dizziness, tiredness
poor circulation
vertigo
depression
intermittant claudication
headache
short term memory loss
dementia
Also for
asthma (reduces bronchoconstriction)
How to prepare
With some difficulty!
The fresh herbs do not in my experience make a good extract as the tough leaves are difficult to grind up.
Dried leaves can be ground and a 1:5 preparation (see St John's Wort) can be made.
This is a long way from a 50:1 preparation but I have used this clinically. (See Reflections).
How much to use
Standardised liquid :The dose is generally in the range of 3-4ml per day.
Standardised tablets : The dose is generally 3 tablets daily (40 mg/tablet) 50:1
This is equivalent to 4-8g of the leaf per day equalling 20-40 mls of a 1:5 extract rather a lot of alcohol. I use around 3-5ml 3x daily of the 1:5.
At least half of the alcohol can be removed by pouring a little boiling water over the extract and leave to cool.
See ‘Keeping the Plants Alive', St John's Wort June/July 2001 for Definitions
Safety and Side effects
People on Warfarin or anti-platelet medication should not use Ginkgo.
It may exacerbate bleeding in women with menorrhagia.
Use with caution during pregnancy.
CONSULT YOUR QUALIFIED MEDICAL HERBALIST, THEY KNOW IF YOU SHOULD BE TAKING GINKGO.
There have been a number of anecdotal cases where Ginkgo, particularly the standardised tablets have caused headaches. The tincture does not seem to produce this effect.
There is the possibility that it could cause minor bleeding incidents especially if the recommended dose is not followed.
It should not be used prior to surgery.
Research reviews :
The research trail through the literature provides some interesting points for reflection. At best in vivo research uses real people with clinically relevant conditions, at worst they use animals, or pharmacological in vitro research and extrapolate the findings into clinical effectiveness.
I will not be referring to those ‘at worst' research papers here.
Most of the summaries of the research papers are repeated again elsewhere. This then becomes the ‘new' latest research. Nowhere on any of the websites advertising Ginkgo products I looked at, was there any reference to research post-1998 and a Fact Sheet by the University of Ohio used ‘An Honest Herbal' by Varro Tyler as its only reference!
I will briefly list the main pre 2000 findings for the record and will cover the human studies since then.
Pre-2000.
39 of 40 clinical trials using Ginkgo in the treatment of cerebral insufficiency had a positive outcome. 26 and this was supported by a further meta-analysis in 8 of 11 double blind trials. 26
The use of Ginkgo in the treatment of people with asthma, dementia, peripheral vascular conditions and Alzhemier's disease is also well supported by the studies.
And although it is often used by people with tinnitus and acute hearing loss this has not been answered by research.26
In a somewhat interesting application of ginkgo, researchers have studied its benefits in assisting patients suffering from anti-depression-induced sexual dysfunction.
"The open study on 63 subjects found that women (33) were more responsive to the sexually enhancing effects than men (30), with relative success rates of 91% compared to 76% for the men. The ginkgo (product brand not noted) was given at a dosage range of 60 to 120 mg twice daily, within the normal range for the usual applications of ginkgo. The ginkgo reportedly had a positive effect on all four phases of the sexual response cycle: desire, excitement (erection and lubrication), orgasm, and resolution (afterglow)." 3
Since 2000…
A number of interesting studies are found in a range of journals.
Ginkgo was found to be statistically significant, in the treatment of people with;
Dementia, 23 Intermittant claudication ,27 Tinnitus (early onset), 15 Haemorrhoids,14 anti-depressant medication induced sleep disturbances, 13 Attention Deficit Hyperactivity Disorder (with Panax quinquefolium) 24
Several studies were carried out on healthy people and showed an inprovement in attention span, 16 and memory enhancement (with Panax schinseng), 38 as well as improvements in the speed of processing information, 33.
Drug medication and Ginkgo use was the focus of a number of studies with caution being made on its use with warfarin, 10 and a general statement that "The true risks of these interactions and effects are difficult to characterize due to the limited number and nature of existing reports".34 Ginkgo is listed as a potential problem pre-operatively, 2 with an increase in post operative bleeding.8
In using it alongside haloperidol, an anti-psychotic drug, ginkgo may work to enhance its efficacy.39
On ageing;
" At present, it is well established that mitochondrial deficits accumulate upon ageing due to oxidative damage" 31 and that Ginkgo may prevent this and the impairment in physiological performance, particularly motor co-ordination. 31
It has also produced promising results in relation to Alzheimers disease for the same reason. 4 People with age-related macular degeneration and Ginkgo use has not been answered in the research. 7
One trial contrasted markedly with previous ones using Ginkgo with people with dementia and resulted no improvement for older people with mild to medium dementia. 35 An analysis of the discrepancy reveals that "study outcomes may vary with the type of population studied, the outcome measurements selected, and the dosing tested". 22
A large involving 1121 people with tinnitus showed Ginkgo to be no more effective than placebo. 5
The previous claims that Ginkgo increased libido in women was supported in a pilot trial on pre and post-menopausal women with a further double-blind study planned. 37
A novel potent anti-fungal protein has been isolated from the seed. 36
Recent Statistics
For the 52 weeks ending Jan 7th 2001 close to $100,000,000 worth of Ginkgo was sold in the USA.
More than 5,000,000,prescriptions are written for Ginkgo in Germany annually.
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REFERENCES
1. Adimoelja A. Related Articles. Phytochemicals and the breakthrough of traditional herbs in the management of sexual dysfunctions. Int J Androl. 2000;23 Suppl 2:82-4.
2. Ang-Lee MK, Moss J, Yuan CS. Related Articles Herbal medicines and perioperative care. JAMA. 2001 Jul 11;286(2):208-16. Review.
3. Blumenthal M, Goldberg A, Brinckmann J. Herbal Medicine. Expanded Commission E Monographs. Integrative Medicine. American Botanical Council 2000. CD-ROM.
4. Christen Y. Related Articles Oxidative stress and Alzheimer disease.
Am J Clin Nutr. 2000 Feb;71(2):621S-629S. Review.
5. Drew S, Davies E. Free in PMC , Related Articles Effectiveness of Ginkgo biloba in treating tinnitus: double blind, placebo controlled trial.
BMJ. 2001 Jan 13;322(7278):73.
6. Drieu K, Vranckx R, Benassayad C, Haourigi M, Hassid J, Yoa RG, Rapin JR, Nunez EA. Related Articles Effect of the extract of Ginkgo biloba (EGb 761) on the circulating and cellular profiles of polyunsaturated fatty acids: correlation with the anti-oxidant properties of the extract. Prostaglandins Leukot Essent Fatty Acids. 2000 Nov;63(5):293-300.
7. Evans JR. Related Articles Ginkgo biloba extract for age-related macular degeneration. Cochrane Database Syst Rev. 2000;(2):CD001775. Review.
8. Fessenden JM, Wittenborn W, Clarke L. Related Articles Gingko biloba: a case report of herbal medicine and bleeding postoperatively from a laparoscopic cholecystectomy. Am Surg. 2001 Jan;67(1):33-5.
9 Fisher C, Painter G. Materia Medica Of Western Herbs In The Southern Hemisphere. 651 West Coast Rd, Oratia, Auckland, 1996.
10.Fugh-Berman A. Related Articles Herb-drug interactions.
Lancet. 2000 Jan 8;355(9198):134-8. Review.
11.Galluzzi S, Zanetti O, Binetti G, Trabucchi M, Frisoni GB. Related Articles Coma in a patient with Alzheimer's disease taking low dose trazodone and gingko biloba.J Neurol Neurosurg Psychiatry. 2000 May;68(5):679-80. No abstract available.
12.Hauns B, Haring B, Kohler S, Mross K, Robben-Bathe P, Unger C. Related Articles Phase II study with 5-fluorouracil and ginkgo biloba extract (GBE 761 ONC) in patients with pancreatic cancer.
Arzneimittelforschung. 1999 Dec;49(12):1030-4.
13.Hemmeter U, Annen B, Bischof R, Bruderlin U, Hatzinger M, Rose U, Holsboer-Trachsler E. Related Articles Polysomnographic effects of adjuvant ginkgo biloba therapy in patients with major depression medicated with trimipramine. Pharmacopsychiatry. 2001 Mar;34(2):50-9.
14.Hep A, Robek O, Skricka T. Related Articles [Treatment of hemorrhoids from the viewpoint of the gastroenterologist. Personal experience with the Ginkor Fort preparation].
Vnitr Lek. 2000 May;46(5):282-5. Czech.
15.Holstein N. Related Articles [Ginkgo special extract EGb 761 in tinnitus therapy. An overview of results of completed clinical trials]. Fortschr Med. 2001 Jan 11;118(4):157-64. Review. German.
16.Kennedy DO, et al. The dose-dependent cognitive effects of acute administration of Ginkgo biloba to healthy young volunteers. Psychopharmacology 151(4): 516 – 423, 2000.
17.Kennedy DO, Scholey AB, Wesnes KA. Related Articles The dose-dependent cognitive effects of acute administration of Ginkgo biloba to healthy young volunteers. Psychopharmacology (Berl). 2000 Sep;151(4):416-23.
18.Kudolo GB, The Effect of 3-month ingestion of Ginkgo biloba extract on pancreatic beta-cell function in response to glucose loading in normal glucose tolerant individuals. J Clin Pharacol 2000 Jun:40(6):647-54
19.Kudolo GB. Related Articles The effect of 3-month ingestion of ginkgo biloba extract (EGb 761) on pancreatic beta-cell function in response to glucose loading in individuals with non-insulin-dependent diabetes mellitus. J Clin Pharmacol. 2001 Jun;41(6):600-11.
20.Kudolo GB. Related Articles The effect of 3-month ingestion of Ginkgo biloba extract on pancreatic beta-cell function in response to glucose loading in normal glucose tolerant individuals.
J Clin Pharmacol. 2000 Jun;40(6):647-54.
21.Le Bars PL, Keiser M, Itil KZ. A 26-week analysis of a double blind, placebo controlled trial of the Ginkgo biloba EGb in dementia 1:Dement Geriatr Cogn Disord 2000 Jul-Aug:11(4):230
22.Le Bars PL, Kastelan J. Related Articles Efficacy and safety of a Ginkgo biloba extract.
Public Health Nutr. 2000 Dec;3(4A):495-9. Review.
23. Le Bars PL, Kieser M, Itil KZ. Related Articles A 26-week analysis of a double-blind, placebo-controlled trial of the ginkgo biloba extract EGb 761 in dementia. Dement Geriatr Cogn Disord. 2000 Jul-Aug;11(4):230-7.
24. Lyon MR, Cline JC, Totosy de Zepetnek J, Shan JJ, Pang P, Benishin C. Related Articles Effect of the herbal extract combination Panax quinquefolium and Ginkgo biloba on attention-deficit hyperactivity disorder: a pilot study. J Psychiatry Neurosci. 2001 May;26(3):221-8.
25. Moher D, Pham B, Ausejo M, Saenz A, Hood S, Barber GG. Related Articles Pharmacological management of intermittent claudication: a meta-analysis of randomised trials. Drugs. 2000 May;59(5):1057-70.
26. Mills S, Bone K. Principles and practice of phytotherapy. Modern herbal medicine. Churchill Livingstone, 2000.
27. Pittler MH, Ernst E. Related Articles Ginkgo biloba extract for the treatment of intermittent claudication: a meta-analysis of randomized trials. Am J Med. 2000 Mar;108(4):276-81.
30. Pratico D, Delanty N. Related Articles Oxidative injury in diseases of the central nervous system: focus on Alzheimer's disease.Am J Med. 2000 Nov;109(7):577-85. Review.
28. Reust CE, Stevermer JJ. Related Articles Is gingko biloba more effective than placebo for the treatment of intermittent claudication? J Fam Pract. 2000 Jul;49(7):657. No abstract available.
29. Robb-Nicholson C. Related Articles By the way, doctor. My surgeon advised me to stop taking gingko biloba before my hip surgery. Can you explain why? Are there any other herbs I should avoid? Harv Womens Health Watch. 2000 Jun;7(10):8. No abstract available.
30. Ritch R. Related Articles Potential role for Ginkgo biloba extract in the treatment of glaucoma.
Med Hypotheses. 2000 Feb;54(2):221-35. Review.
31.Sastre J, Pallardo FV, Garcia de la Asuncion J, Vina J. Related Articles Mitochondria, oxidative stress and aging. Free Radic Res. 2000 Mar;32(3):189-98. Review.
32. Sastre J, Pallardo FV, Vina J. Related Articles Mitochondrial oxidative stress plays a key role in aging and apoptosis. IUBMB Life. 2000 May;49(5):427-35. Review.
33.Stough C, Clarke J, Lloyd J, Nathan PJ. Neuropsychological changes after 30-day Ginkgo biloba administration in healthy participants. Int J Neuropsychopharmacol. 2001 Jun;4(2):131-4.
34.Vaes LP, Chyka PA. Related Articles Interactions of warfarin with garlic, ginger, ginkgo, or ginseng: nature of the evidence.Ann Pharmacother. 2000 Dec;34(12):1478-82. Review.
35.van Dongen MC, van Rossum E, Kessels AG, Sielhorst HJ, Knipschild PG. Related Articles The efficacy of ginkgo for elderly people with dementia and age-associated memory impairment: new results of a randomized clinical trial. J Am Geriatr Soc. 2000 Oct;48(10):1183-94.
36. Wang H, Ng TB. Related Articles Ginkbilobin, a novel antifungal protein from Ginkgo biloba seeds with sequence similarity to embryo-abundant protein. Biochem Biophys Res Commun. 2000 Dec 20;279(2):407-11.
37. Waynberg J, Brewer S. Related Articles Effects of Herbal vX on libido and sexual activity in premenopausal and postmenopausal women. Adv Ther. 2000 Sep-Oct;17(5):255-62.
38. Wesnes KA, Ward T, McGinty A, Petrini O. Related Articles The memory enhancing effects of a Ginkgo biloba/Panax ginseng combination in healthy middle-aged volunteers. Psychopharmacology (Berl). 2000 Nov;152(4):353-61.
39. Zhang XY, Zhou DF, Su JM, Zhang PY. The effect of extract of Ginkgo biloba added to haloperidol on superoxide dismutase in inpatients with chronic schizophrenia. J Clin Psychopharm 2001 Feb;21(1):85-8
Website The Ginkgo Pages www.xs4all.nl/~kwanten/history.htm
Reflections
At a dose of 50:1, is it herbal medicine or pharmaceutical drug?
How is this degree of standardisation of a plant prepared? Please send me an E-mail if you know this.
At this strength then some potentially toxic constituents may have needed to be removed ie Ginkgolic acid and other potentially beneficial constituents may have been removed?
So the tree that has witnessed the dawn of many centuries is restored to its former place as an inhabitant of the temperate world and is here to stay…
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