Abstracts

Anticlastogenic

Anticlastogenic

Clastogenic factors (CFs) were first described in the blood of persons irradiated accidentally or for therapeutic reasons. Work of our laboratory has shown that they occur also under other circumstances, which are characterized by oxidative stress, and that CF-induced chromosome damage is regularly prevented by superoxide dismutase (SOD). 9

Recently we found CFs in a high percentage of salvage personnel of the Chernobyl reactor accident. These liquidators represent a high-risk population and might benefit from cancer chernoprevention by antioxidants. SOD would have to be injected and is not appropriate for long-term prophylactic treatment.

In the present study, we therefore evaluated the anticlastogenic effect of the Ginkgo biloba extract EGb 761, which is known for its superoxide scavenging properties.

Preliminary results obtained in a small series of liquidators showed regression or complete disappearance of CFs in the plasma after 2 months of treatment with EGb 761 (3 x 40 mg/d).

Radiation-induced clastogenic factors: anticlastogenic effect of Ginkgo biloba extract. Emerit-1; Arutyunyan-R; Oganesian-N; Levy-A; CernJavsky-L; Sarkisian-T; Pogossian-A; Asrian-K. Free-Radic-Biol-Med. 1995 Jun; 18(6): 985-91.

Ginkgo & Antioxidants

Antioxidant

Iron can induce a peroxidative degradation of the membrane polyunsaturated fatty acids by the well-known Fenton reaction. Chelated iron can also form a complex with oxygen, called perferryl ion, which is able to induce lipoperoxidation without a detectable production of hydroxyl radicals.

The antioxidant properties of a titrated and standardized extract of Ginkgo biloba leaves (EGb 76 1) against iron-dependent peroxidative degradation of the membrane polyunsaturated fatty acids were studied.

EGb 761 protects these membrane polyunsaturated fatty acids regardless of their susceptibility to peroxidation. This protective effect is correlated with the decrease in the thiobarbituric acid-reactive substances concentration, but the calculation of the antioxidant potency of EGb 761 as an IC50 value using results of the thiobarbituric acid reaction leads to an underestimated evaluation when the reaction is carried out in the presence of iron ions.

Protection of polyunsaturated fatty acids against iron-dependent lipid peroxidation by a Ginkgo biloba extract (EGb 761). Dumont-E; D'Arbigny-P; Nouvelot-A. Methods-Find-Exp-Clin-Pharmacol. 1995 Mar; 17(2): 83-8.

Antioxidant mechanisms have been proposed to underlie the beneficial pharmacological effects of EGb 761, an extract from Ginkgo biloba leaves used for treating peripheral vascular diseases and cerebrovascular insufficiency in the elderly. In vitro evidence has been reported that EGb 761 scavenges various reactive oxygen species, i.e. nitric oxide, and the superoxide, hydroxyl, and oxoferryl radicals.

However, the ability of EGb 761 to scavenge peroxyl radicals (reactive species mainly involved in the propagation step of lipid peroxidation) has not been investigated.

This extends the oxygen radical scavenging properties of the extract and supports the hypothesis of an antioxidant therapeutic action of EGb 761.

Peroxyl radical scavenging activity of Ginkgo biloba extract EGb 761. Maitra-1; Marcocci-L; Droy-Lefaix-MT; Packer-L. Biochem-Phannacol. 1995 May 26; 49(11): 1649-55.

Ginkgo biloba extract is known to be efficient in diseases associated with free radical generation. This study compares the in vitro effect of some constituents of Ginkgo against lipid peroxidation and cell necrosis of isolated rat hepatocytes, and against superoxide anion which is generally implicated in cell damages.

Efficiency of Ginkgo biloba extract (EGb 76 1) in antioxidant protection against myocardial ischemia and reperfusion injury. Shen-JG; Zhou-DY. Biochem-Mol-Biol-Int. 1995 Jan; 35(l): 125-34.

The cardio-protective mechanisms of EGb 761, an extract of Ginkgo biloba leaves, on myocardial ischemia-reperfusion injury were investigated using rabbits subjected to 30 minutes of regional cardiac ischernia and 120 min of reperfusion under anesthesia.

Compared to the saline perfused group, EGb 761 treatment (10 mg/kg, injected into the coronary artery) significantly inhibited the increase in lipid peroxidation and maintained total and CuZn-SOD levels in both plasma and tissue during and at the end of reperfusion. Both the decrease in tissue type plasminogen activator (t-PA) and the increase in plasminogen activator inhibitor- I (PAI-1) caused by ischemia-reperfusion were also significantly suppressed by EGb 761 treatment.

Furthermore, the ultrastructure of the myocytes of the EGb 761 treated heart was slightly damaged after ischemia-reperfusion, while the control ischemic-reperfused hearts demonstrated severe histological damages such as swelling and vacuolization of the mitochondria.

These results suggest that EGb 761 protects hearts by its antioxidant properties and by its ability to adjust fibrinolytic activity.

Inhibition of preretinal proliferation by free radical scavengers in an experimental model of tractional retinal detachment. Baudouin-C; Ettaiche-M; Imbert-F; Droy-Lefaix-MT; Gastaud-P; Lapalus-P. Exp- Eye-Res. 1994 Dec; 59(6): 697-706.

An original model of experimental proliferative vitreoretinopathy was developed in pigmented rabbits.

Results demonstrate that antioxidants may efficiently prevent preretinal proliferation, in clinicopathological entities where free radicals had not yet been shown to play a direct pathogenetic role. They are also among the first attempts for inhibiting preretinal proliferations with non-cytotoxic agents and using a non-ocular route.

Anti-stress

Anti-stress

Results indicate that EGb 761 can facilitate behavioral adaptation despite adverse environmental influences, a property that supports its clinical use in treating cognitive impairment, especially in elderly patients.

Demonstration of the "anti-stress" activity of an extract of Ginkgo biloba (EGb 761) using a discrimination learning task. Rapin-JR; Lamproglou-I; Drieu-K; DeFeudis-FV. Gen-Pharmacol. 1994 Sep; 25(5): 1009-16.

EEG

EEG

Significant amplitude increase was found in 1-2 and 2-4 Hz frequency bands in one diabetic group of rats compared with control, but no differences were found for other groups.

Agar-A; Yargicoglu-P; Apaydin-KC; Oguz-Y: The effect of ginkgo biloba extract on EEG spectra in experimental diabetes: no relation to lipid peroxidation. Int-J-Neurosci. 1994 Jun; 76(3-4): 259-66.

Flavonoids & Ginkgo

Flavonoids

Examined The antioxidant action of myricetin and quercetin, the flavonoid constituents of the extract of Ginkgo biloba (EGb), on oxidative metabolism of brain neurons.

Antioxidant action of myricetin or quercetin may be responsible for a part of the beneficial effects of EGb on brain neurons subject to ischemia.

Oyama-Y; Fuchs-PA; Katayama-N; Noda-K: Myricetin and quercetin, the flavonoid constituents of Ginkgo biloba extract, greatly reduce oxidative metabolism in both resting and Ca(2+)-loaded brain neurons. Brain-Res. 1994 Jan 28; 635(1-2): 125-9.

Ischemia

Ischemia

We studied the effect of preconditioning and Ginkgo biloba extract (EGb 76 1) in relation to the recovery of contractile fimction after global ischernia in the isolated working rat heart.

EGb 761, a free-radical scavenger, was chosen to improve myocardial contractile function in preconditioned hearts. Fifty and 100 mg/kg of EGb 761 (per os) significantly improved coronary flow, aortic flow, left ventricular developed pressure (LVDP), and the first derivative of LVDP (LVDdP/dtmax) in the four-cycle preconditioned group.

During reperfusion, the formation of free radicals was reduced by approximately 50 and 60% using 50 mg/kg and 100 mg/kg of EGb 761.

EGb 761 can improve contractile function after global ischernia in the isolated working rat heart by reducing the formation of oxygen free radicals and this protection is additive to that of ischemia-induced preconditioning.

Tosaki-A; Engelman-DT; Pali-T; Engelman-RM; Droy-Lefaix-MT: Ginkgo biloba extract (EGb 761) improves postischernic function in isolated preconditioned working rat hearts. Coron-Artery-Dis. 1994 May; 5(5): 443-50

The antiischemic effect of EGb 761 was studied by measuring the transcutaneous partial pressure of oxygen (TcPo2) during exercise. Transcutaneous oximetry during exercise provides a good, noninvasive estimation of local arterial perfusion and constitutes a real index of local and regional capillary perftision.

The first group received 320 mg per day of EGb 761 for four weeks and the second group received placebo. The treadmill walking test was performed under standardized conditions at the same time of day and by the same investigator. In a comparison of the differences before and after treatment, the areas of ischernia decreased by 38% in the EGb 761 group but remained essentially stable (+5%) in the placebo group.

This study confirmed the rapid antiischemic action of EGb 761 and its value in the management of peripheral arterial occlusive disease at the stage of intermittent claudication.

Aging (Ginkgo)

Aging

Chronic treatment with Ginkgo biloba extract did not alter binding in young rats but increased binding density significantly (33%) in aged rats, suggesting a restorative effect in aged rats, associated with decreased receptor density resulting from the protective action of Ginkgo biloba extract treatment on neuronal membrane.

Huguet-F; Drieu-K; Piriou-A: Decreased cerebral 5-HTIA receptors during ageing: reversal by Ginkgo biloba extract (EGb 761). J-Pharm-Pharmacol. 1994 Apr; 46(4): 316-8.

Mouren-X; Caillard-P; Schwartz-F: Study of the antiischernic action of Ginkgo biloba Extract [EGb 761 ] in the treatment of peripheral arterial occlusive disease by TcPo2 determination. Angiology. 1994 Jun; 45(6): 413-7.

Pancreas

Pancreas

EGb 761 (200 mg/kg/day, p.o.) protected beta cells against the toxic effects of alloxan (50 mg/kg, i.v). Since bilobalide and ginkgolide B caused opposite effects on the sensitivity of beta cells to glucose, the stimulatory effect of EGb 761 may be attributed to its content of bilobalide.

Vasseur-M; Jean-T; DeFeudis-FV; Drieu-K: Effects of repeated treatments with an extract of Ginkgo biloba (EGb 761), bilobalide and ginkgolide B on the electrical activity of pancreatic beta cells of normal or alloxan-diabetic mice: an ex vivo study with intracellular microelectrodes. Gen-Pharmacol. 1994 Jan; 25(1): 31-46.

Pharmacokinetics

Pharmacokinetics

The pharmacokinetics of Ginkgolide A, Ginkgolide B and Bilobalide, which are compounds extracted from the dried leaves of the Ginkgo biloba tree, were investigated in healthy volunteers (six men and six women.

When given orally, while fasting, the extents of bioavailability were high.

[Pharmacokinetic properties of Bilobalide and Ginkgolides A and B in healthy subjects after intravenous and oral administration of Ginkgo biloba extract (EGb 761)] Fourtillan-JB; Brisson-AM; Girault-J; Ingrand-I; Decourt-JP; Drieu-K; Jouenne-P; Biber-A. Therapie. 1995 Mar-Apr; 50(2): 137-44.

Platelets (Ginkgo)

Platelets

Ginkgo biloba special extract exerts positive effects on hemorheology and platelet aggregation, is a free radical scavenger and possesses PAD antagonistic properties, protects against hypoxia and ischernia, hampers an experimentally induced cerebral edema, has favorable properties on neurotransmitters and enhances cerebral bloodflow. Clinically, Egb has proven favorable effects on intellectual deficiency, equilibrium disturbances and peripheral artery occlusions thus being a drug with a clear-cut indication for these diseases.

Hitzenberger-G.: The effect of ginkgo biloba special extract (EGb 76 1, Tebofortan). Wien-Med-Wochenschr,1992,142(17): 371-9.

Retina

Retina

Lesions, inflammations, or degenerative insults of the human retina are accompanied by the release of proteolytic enzymes. Their deleterious effect may be enhanced by the release of free radicals. Ginkgo biloba extracts are known to exert protective influences against the action of free radicals, and this prompted us to ask whether the application of such extracts might protect retinal tissue against proteolytic damage.

There was a significant protective action of EGb 761: in an average control rabbit 5,200 cells per milligram retinal tissue were isolated; application of EGb 761 markedly reduced this number to 2,500 (terpene-free fraction; CP 205) or 3,050 (terpene-containing fraction).

It is concluded that G. biloba extracts may have a significant therapeutic value in cases of retinal damage.

Pritz-Hohmeier-S; Chao-TI; Krenzlin-J; Reichenbach-A: Effect of in vivo application of the ginkgo biloba extract EGb 761 (Rokan) on the susceptibility of mammalian retinal cells to proteolytic enzymes. Ophthalmic-Res. 1994; 26(2): 80-6

Scavenging

Scavenging

Ginkgo biloba extract EGb 761 was found to be a scavenger of nitric oxide in in vitro acellular systems, under physiological conditions. These data implicate it as a potential therapeutic agent in conditions of altered production of nitric oxide.

Marcocci-L; Maguire-JJ; Droy-Lefaix-MT; Packer-L: The nitric oxide-scavenging properties of Ginkgo biloba extract EGb 761. Biochem-Biophys-Res-Commun. 1994 Jun 15; 201(2): 748-55.

Stress

Stress

In rats, stress-induced detrimental changes in both discrimination learning and plasma hormones were suppressed by 20 days of oral treatment with an extract of Ginkgo biloba leaves (EGb 761; 50 or 100 mg/kg/day) in both young and old rats, effects that became statistically significant by the third day of learning (time of maximal acquisition rate.

These results indicate that EGb 761 can facilitate behavioral adaptation despite adverse environmental influences, a property that supports its clinical use in treating cognitive impairment, especially in elderly patients.

Rapin-JR; Lamproglou-I; Drieu-K; DeFeudis-FV: Demonstration of the "anti-stress" activity of an extract of Ginkgo biloba (EGb 761) using a discrimination learning task. Gen-Pharmacol. 1994 Sep; 25(5): 1009-16.

Tinnitus

Tinnitus

Previous studies have shown contradictory results of Ginkgo biloba extract (GBE) treatment of tinnitus. 7 patients preferred GBE to placebo, 7 placebo to GBE and 6 patients had no preference. Statistical group analysis gives no support to the hypothesis that GBE has any effect on tinnitus, although it is possible that GBE has an effect on some patients due to several reasons, e.g. the diverse etiology of tinnitus. Since there is no objective method to measure the symptom, the search for an effective drug can only be made on an individual basis.

Holgers-KM; Axelsson-A; Pringle-I: Ginkgo biloba extract for the treatment of tinnitus. Audiology. 1994 Mar-Apr; 33(2): 85-92.

Vestibular

Vestibular

Unilateral vestibular deafferentation (UVD) causes ocular motor and postural disorders, some of which disappear over time in a process of behavioral recovery known as vestibular compensation. Review the present status of drugs which enhance the vestibular compensation process either by reducing the initial symptoms of UVD or by accelerating the compensation process: melanotropic peptides, calcium antagonists and gangliosides/Ginkgo Biloba extract EGb 761.

Concluded that the evidence supporting the efficacy of the melanotropic peptides and the Ginkgo Biloba extract EGb 761 in accelerating compensation is the most convincing; by comparison, the evidence relating to the effects of calcium antagonists on vestibular compensation is more controversial.

Smith-PF; Darlington-CL: Can vestibular compensation be enhanced by drug treatment? A review of recent evidence.
J-Vestib-Res. 1994 May-Jun; 4(3): 169-79.

Equilibrium Disorders

Equilibrium disorders

Gingko biloba may help patients suffering from vertigo and/or dizziness caused by vascular vestibular disorders. In a open, controlled trial, 44 patients with symptoms of vertigo, dizziness, or both, were administered either with extract of ginkgo biloba (EGb 761) or with betahistine dihydrochloride (BI). During the first month of the clinical trial, 64.7% of the patients treated with BI, and 65% of those who received EGb 761 had fewer symptoms of vertigo and dizziness. The results showed that gingko and betahistine dihydrochloride operate at different equilibrium receptor sites, and gingko may be effective in improving oculomotor and visuovestibular function.

Cesarani A, Meloni F, Alpini D, Barozzi S, Verderio L, Boscani PF: Ginkgo biloba (EGb 761) in the treatment of equilibrium disorders, Adv Ther 1998 Sep-Oct; 15(5): 291-304

Hepatic Damage

Hepatic damage

Ginkgo biloba extract exhibits a protective effect on carbon tetrachloride induced hepatic damage in rats. In this study, the rats were firstly administered Ginkgo biloba extract orally for 10 days, and then a single dose of carbon tetrachloride was administered. Ginkgo biloba extract treatment lowered hepatic malondialdehyde levels significantly, while glutathione and hydroxyproline levels remained unchanged. Gingko biloba may act as a protective barrier against carbon tetrachloride induced liver damage.

Ozenirler S, Dincer S, Akyol G, Ozogul C, Oz E: The protective effect of Ginkgo biloba extract on CCl4-induced hepatic damage, Acta Physiol Hung 1997-98; 85(3): 277-85

Neurotoxicity

Neurotoxicity

Gingko biloba (Egb) and its active constituent ginkolide B (Gin B) may inhibit glutamate (Glu) neurotoxicity in neurons. The extract of leaves of Ginkgo biloba L (EGb) and several of its active constituents were examined. The results demonstrated that 2.5 mg of Egb, and 2 mg of its active constituent ginkgolide B (Gin B), protected the neurons from Glu-induced injury, and prevented the Glu-induced elevation in [Ca2+]. Due to its protective properties, Gingko biloba may prevent neurotoxicity induced by glutamate.

Zhu L, Wu J, Liao H, Gao J, Zhao XN, Zhang ZX: Antagonistic effects of extract from leaves of ginkgo biloba on glutamate neurotoxicity, Chung Kuo Yao Li Hsueh Pao 1997 Jul; 18(4): 344-7

Cognitive Impairment (Ginkgo)

Cognitive Impairment

In contrast to other kinds of psychotropic drugs, nootropics or cognition enhancing drugs may be indicated, not for the direct treatment of the pathology itself, but for improving or restoring the remaining brain functions. Brain functions are normally trained during various kinds of non?medical therapy, such as physiotherapy, speech therapy, occupational therapy, memory training etc... In research little attention has been paid to the combination of both kinds of therapeutic approaches, probably because of the important methodological difficulties. This combination however, offers various interesting perspectives

Interaction between psychological and pharmacological treatment in cognitive impairment. Deberdt?W. Life?Sci. 1994; 55(25?26): 2057?66.

Alzheimer's Disease (Ginkgo)

Alzheimer's disease

Gingko biloba may induce pharmacological effects in the central nervous system (CNS) of the elderly similar to anti-dementia drugs approved in the United States and Europe. In this study, the pharmacological effects of gingko biloba and tacrine (a drug used to treat Alzheimer's) on elderly subjects having possible or probable Alzheimer's were observed. Eighteen subjects (11 males, 7 females) at a median age of 67.4 years with light to moderate dementia participated in the study. Each subject was administered a single dose of either 40 mg tacrine or 240 mg gingko in two separate sessions within 3 to 7 day intervals. The results showed that while both induced pharmacological effects, gingko's effect was greater. Gingko biloba may be effective in treating Alzheimer's and dementia patients.

Itil TM, Eralp E, Ahmed I, Kunitz A, Itil KZ: The pharmacological effects of ginkgo biloba, a plant extract, on the brain of dementia patients in comparison with tacrine, Psychopharmacol Bull 1998; 34(3): 391-7

Cerebrovascular Insufficiency

Cerebrovascular Insufficiency

Eleven controlled clinical trials were evaluated in"a meta-analysis in order to prove the effectiveness of the ginkgo biloba special extract LI 1370 (Kaveri forte). All included studies were placebo controlled randomized double blind studies, using in most of the cases a daily dosage of 150 mg extract.

The analysis of the total score of clinical symptoms from all relevant studies indicated that 7 studies confirmed the effectiveness (Ginkgo biloba being better compared to placebo) while only one study was inconclusive (the medications were not different). This relation confirms the therapeutical effectiveness of ginkgo biloba regarding the clinical symptom complex.

[Evidence for a therapeutic effect of Ginkgo biloba special extract. Meta-analysis of I I clinical studies in patients with cerebrovascular insufficiency in old age] Hopfenmuller-W. Armeimittelforschung. 1994 Sep; 44(9): 1005-13.

Ginkgo Biloba in Dementia

Dementia

Natural substances and/or their synthetically developed active ingredients are frequently used in medicine. In psychiatry, two of the most well known natural compounds are reserpine and Ginkgo biloba extract (EGb). EGb is among the most popular over-the-counter medicines in Europe and is also available in the United States, primarily in health food stores. Already the European medical community has recognized EGb as an effective compound in the treatment of cerebral insufficiency.

Recent studies in which EGb 761 demonstrated therapeutic effects in the treatment of dementia have earned EGb the approval of the German BGA (Bundesgesundheit Amt) for use in the treatment of dementia.

Natural substances in psychiatry (Ginkgo biloba in dementia). Itil-T; Martorano-D. Psychopharmacol-Bull. 1995; 31(l): 147-58.

Lipoprotein Oxidation

Lipoprotein Oxidation

The antioxidant effects of Ginkgo biloba extract (EGb 76 1) on copper-mediated human low density lipoprotein (LDL) oxidative modification were evaluated.

EGb 761 has powerful antioxidant effects on copper-mediated LDL oxidative modification.

Ginkgo biloba extract (EGb 761) protects human low density lipoproteins against oxidative modification mediated by copper. Yan-LJ; Droy-Lefaix-MT; Packer-L. Biochem-Biophys-Res-Commun. 1995 Jul 17; 212(2): 360-6.

Lipoperoxidation induced by hydrogen peroxide in human erythrocyte membranes. 2. Comparison of the antioxidant effect of Ginkgo biloba extract (EGb 761) with those of water-soluble and lipid-soluble antioxidants. Kose-K; Dogan-P. J-Int-Med-Res. 1995 Jan-Feb; 23(l): 9-18.

An in vitro model using healthy human erythrocyte suspensions was used to compare the antioxidant effect of standardized Ginkgo biloba extract (EGb 761) with those of water-soluble (ascorbic acid, glutathione and uric acid) and lipid-soluble (alpha-tocopherol and retinol acetate) antioxidants. Lipid peroxidation was induced by hydrogen peroxide in the absence (control) and presence of antioxidants at low (25 micrograms/ml) and high (250 micrograms/ml) concentrations. Malondialdehyde production was determined as the indicator of lipid peroxidation during the incubation period. The results suggest that all of the antioxidants, except ascorbic acid, have antioxidant potential in this system in a concentration-dependent manner.

When the antioxidants were compared, EGb 761 was found to be more effective than water-soluble antioxidants, and as effective as lipid-soluble antioxidants.

Among the lipid-soluble antioxidants there was no significant difference in potency between alpha-tocopherol and retinol acetate, but uric acid was the most potent of the water-soluble antioxidants. The antioxidant potency of EGb 761 appears to be comparable with that of the well-known antioxidants alpha-tocopherol and retinol acetate.

Lipoperoxidation induced by hydrogen peroxide in human erythrocyte membranes. 1. Protective effect of Ginkgo biloba extract (EGb 761). Kose-K; Dogan-P. J-Int-Med-Res. 1995 Jan-Feb; 23(l): 1-8.

The antioxidant potential of Ginkgo biloba extract (EGb 761) on healthy human erythrocyte membranes was investigated. Lipoperoxidation was induced in erythrocyte suspensions using hydrogen peroxide, in the presence of EGb 761 at 37 degrees C; malondialdehyde production was determined as the indicator of lipoperoxidation during the incubation period.

The results for EGb 761 at concentrations of 0, 25, 50, 125, 250 and 500 micrograms/ml suggest that the antioxidant potential of EGb 761 in erythrocyte membranes increases with dose. Similarly, using different incubation periods (0, 15, 30, 45 or 60 min) indicated that the antioxidant effect of EGb 761 increased by the incubation time.

Comparative antilipoperoxidant, antinecrotic and scavenging properties of terpenes and biflavones from Ginkgo and some flavonoids. Joyeux-M; Lobstein-A; Anton-R; Mortier-F. Planta-Med. 1995 Apr; 61(2): 126-9.

Myocardial Ischemia

Myocardial Ischemia

Recently, it was reported that Ginkgo biloba extract (EGb 761), which is known to have antioxidant properties, also has antiarrhythmic effects on cardiac reperftision-induced arrhythmias. In the present study, effects of EGb 761 on cardiac ischemia-reperfusion injury were investigated from the point of view of recovery of mechanical function as well as the endogenous antioxidant status of ascorbate.

Isolated rat hearts were perfused using the Langendorff technique, and 40 min of global ischemia were followed by 20 min of reperfusion. EGb 761 improved cardiac mechanical recovery and suppressed the leakage of lactate dehydrogenase (LDH) during reperfusion. Furthermore, EGb 761 diminished the decrease of myocardial ascorbate content after 40 min of ischernia and 20 min of reperfusion. Interestingly, EGb 761 also suppressed the increase of dehydroascorbate.

These results indicate that EGb 761 protects against cardiac ischemia-reperfusion injury and suggest that the protective effects of EGb 761 depend on its antioxidant properties.

Haramaki-N; Aggarwal-S; Kawabata-T; Droy-Lefaix-MT; Packer-L: Effects of natural antioxidant ginkgo biloba extract (EGB 761) on myocardial ischemia-reperfusion injury. Free-Radic-Biol-Med. 1994 Jun; 16(6): 789-94.

Myth and Reality (Ginkgo)

Myth and Reality

Ginkgo biloba is one of the oldest, still existing plants. Extracts from its leaves were already used in ancient China whereas in the Western World, they have been utilized only since the Sixties when it became technically possible and feasible to isolate the essential substances of Ginkgo biloba.

Pharmacologically, there are two groups of substances which are of some significance: the flavonoids, effective as oxygen-free radical scavengers, and the terpenes (i.e. the ginkgolides) with their highly specific action as platelet activating factor (PAF) inhibitors.

Clinically important indications for Ginkgo biloba extracts are cerebral insufficiency and atherosclerotic disease of peripheral arteries of intermediate severity.

In several placebo-controlled clinical studies, symptoms of cerebral insufficiency have been effectively and significantly influenced. Most of these investigations have examined the efficacy of Ginkgo biloba extracts such as EGb 761 and LI 1370.

[Ginkgo--myth and reality] Z'Brun-A. Schweiz-Rundsch-Med-Prax. 1995 Jan 3; 84(1): 1-6.

Review Article (Ginkgo)

Review Article

Ginkgo biloba is one of the oldest, still existing plants. Extracts from its leaves were already used in ancient China whereas in the Western World, they have been utilized only since the Sixties when it became technically possible and feasible to isolate the essential substances of Ginkgo biloba. Pharmacologically, there are two groups of substances which are of some significance: the flavonoids, effective as oxygen-free radical scavengers, and the terpenes (i.e. the ginkgolides) with their highly specific action as platelet activating factor (PAF) inhibitors. Clinically important indications for Ginkgo biloba extracts are cerebral insufficiency and atherosclerotic disease of peripheral arteries of intermediate severity. In several placebo-controlled clinical studies, symptoms of cerebral insufficiency have been effectively and significantly influenced. Most of these investigations have examined the efficacy of Ginkgo biloba extracts such as EGb 761 and LI 1370.

Z'Brun-A: Ginkgo--myth and reality. Schweiz-Rundsch-Med-Prax. 1995 3; 84(l): 1-6.

Spinal Cord Injury

Spinal Cord Injury

Ischaemia-induced lipid peroxidation is one of the most important factors producing tissue damage in spinal cord injury. In our study, the protective effects of Ginkgo biloba, thyroid releasing hormone (TRH) and methylprednisolone (MP) on compression injury of the rat spinal cord were investigated.

Results suggest that MP and Ginkgo biloba may have a protective effect against ischaernic spinal cord injury by the antioxidant effect.

Lipid peroxidation in experimental spinal cord injury. Comparison of treatment with Ginkgo biloba, TRH and methylprednisolone. Koc-RK; Akdemir-H; Kurtsoy-A; Pasaoglu-H; Kavuncu-I; Pasaoglu-A; Karakucuk-I. Res-Exp-Med-Berl. 1995; 195(2): 117-23.

Stressor Adaptation

Stressor Adaptation

The effects of sub-chronic cold stress on the functioning of hippocampal 5-HT1A receptors in old isolated rats and the possible protective effects of Ginkgo biloba extract (EGb 761) were investigated.

Results clearly indicate that 5-HT1A receptors are desensitized by stress and point out the reduced capacity of old rats to cope with the adverse effects of a chronic stressor. EGb 761 appears to restore the age-related decreased capacity to adapt to a chronic stressor.

Stress-induced 5-HT1A receptor desensitization: protective effects of Ginkgo biloba extract (EGb 761). Bolanos-Jimenez-F; Manhaes-de-Castro-R; Sarhan-H; Prudhomme-N; Drieu-K; Fillion-G. Fundam-Clin-Pharmacol. 1995; 9(2): 169-74.