Title
A Ginkgo biloba extract (EGb 761) prevents mitochondrial aging by protecting against
oxidative stress.
Author
Sastre J; Millán A; García de la Asunción J; Plá R; Juan G; Pallardó; OConnor E; Martin
JA; Droy Lefaix MT; Viña J
Source
Free Radic Biol Med, 1998 Jan, 24:2, 298-304
Abstract
The effect of aging on indices of oxidative damage in rat mitochondria and the protective
effect of the Ginkgo biloba extract EGb 761 was investigated. Mitochondrial DNA from
brain and liver of old rats exhibited oxidative damage that is significantly higher than that
from young rats. Mitochondrial glutathione is also more oxidized in old than in young rats.
Peroxide formation in mitochondria from old animals was higher than in those from young
ones. According to morphological parameters (size and complexity), there are two
populations of mitochondria. One is composed of large, highly complex mitochondria, and
the other population is smaller and less complex. Brain and liver from old animals had a
higher proportion of the large, highly complex mitochondria than seen in organs from
young animals. Treatment with the Ginkgo biloba extract EGb 761 partially prevented these
morphological changes as well as the indices of oxidative damage observed in brain and
liver mitochondria from old animals.

Title
Effects of flavonoids of Ginkgo biloba on proliferation of human skin fibroblast.
Author
Kim SJ; Lim MH; Chun IK; Won YH
Source
Skin Pharmacol, 1997, 10:4, 200-5
Abstract
Ginkgo biloba studies have focused on the anti-inflammatory effects of the major
components, ginkgolide and bilobalide, whereas little is known about their effect on
fibroblasts. This study demonstrated the enhancing effects of Ginkgo L. extracts, especially
the flavonoid fractions: quercetin, kaempferol, sciadopitysin, ginkgetin, isoginkgetin, on the
proliferation of normal human skin fibroblast in vitro measured by MTT
(3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide) assay and direct
hemocytometer cell count. Furthermore, increased production of collagen and extracellular
fibronectin were documented by radioisotope (2,3-3H-proline) incorporated collagen assay,
procollagen type I C-peptide assay and by immunoturbidimetric assay. These proliferative
effects suggest another useful pharmacologic application of Ginkgo L. extracts in addition to
their well-known anti-inflammatory effect.

Title
Chemistry and biology of alkylphenols from Ginkgo biloba L.
Author
Jaggy H; Koch E
Source
Pharmazie, 1997 Oct, 52:10, 735-8
Abstract
Ginkgolic acid and related alkylphenols constitute major components of the lipid fraction of
the fruit pods of Ginkgo biloba L. In addition, this class of substances is present in Ginkgo
leaves which are widely used to prepare extracts for the treatment of peripheral or cerebral
circulatory disorders, as well as vascular and Alzheimer type dementia. The present paper
reviews the literature on chemical and biological aspects of alkylphenols from Ginkgo with
special reference to their allergic and other undesired properties. As these compounds are
present in crude leaf extracts, their completest possible removal has therefore to be
guaranteed for therapeutically used extracts by the production process. Technically this does
not imply any problem and most preparations available on the market fulfil the requirements
of the Monograph of the Commission E of the former Federal German Health Authority
(Bundesgesundheitsamt, BGA) requesting a maximal concentration of 5 ppm ginkgolic
acids.

Title
Ginkgo biloba attenuates oxidative stress in macrophages and endothelial cells.
Author
Rong Y; Geng Z; Lau BH
Source
Free Radic Biol Med, 1996, 20:1, 121-7
Abstract
The action of Ginkgo biloba extract (GBE) as an antioxidant was studied using various
models of oxidative stress in macrophages and vascular endothelial cells. GBE was
incubated with murine macrophages (J774) at 37 degrees C and 5% CO2 for 1 h; oxidative
burst was triggered by zymosan. The intensity of fluorescence was measured directly in
96-well plates using a computerized microplate fluorometer at 485 nm excitation and 530
nm emission. GBE exhibited both time- and concentration-dependent suppression of
oxidative burst. Confluent monolayers of bovine pulmonary artery endothelial cells (PAEC)
were preincubated with different concentrations of GBE for 16 h, washed, and then exposed
to an organic oxidant tert-butyl hydroperoxide (tBHP) for 2 h. Lipid peroxidation products
of PAEC were determined by measuring thiobarbituric acid-reactive substances (TBARS).
Cell injury was assessed by measuring the release of intracellular lactate dehydrogenase
(LDH), and cell viability was determined by the methylthiazol tetrazolium (MTT) assay.
tBHP increased production of TBARS in PAEC. Preincubation with GBE inhibited the
increase of TBARS induced by tBHP. GBE protected biomembranes from oxidative injury
by decreasing intracellular LDH leakage from PAEC. MTT assay showed that GBE
minimized loss of cell viability induced by oxidative injury. The extensive antioxidant effect
of GBE may be valuable to the prevention and treatment of various disorders related to free
radical-induced pathology.

Title
Ginkgo biloba extract for the treatment of tinnitus.
Author
Holgers KM; Axelsson A; Pringle I
Source
Audiology, 1994 Mar, 33:2, 85-92
Abstract
Previous studies have shown contradictory results of Ginkgo biloba extract (GBE)
treatment of tinnitus. The present study was divided into two parts: first an open part,
without placebo control (n = 80), followed by a double-blind placebo-controlled study (n =
20). The patients included in the open study were patients who had been referred to the
Department of Audiology, Sahlgren's Hospital, Göteborg, Sweden, due to persistent severe
tinnitus. Patients reporting a positive effect on tinnitus in the open study were included in the
double-blind placebo-controlled study (20 out of 21 patients participated). 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.

Title
Effects of Ginkgo biloba extract (EGb 761) on learning and possible actions on aging.
Author
Cohen Salmon C; Venault P; Martin B; Raffalli Sébille MJ; Barkats M; Clostre F; Pardon
MC; Christen Y; Chapouthier G
Source
J Physiol Paris, 1997 Dec, 91:6, 291-300
Abstract
A study of the effect of Ginkgo biloba extract (EGb 761) has shown enhancing effects on
training in adult and aged Swiss mice. An analysis of inbred mice has confirmed this
sensitivity to EGb 761, but depending on the strains, with different effects at different ages.
The most interesting results are related to improvements in performances observed with
aged mice of the DBA/2J strain. The results obtained with inbred strains in the study of the
mossy fibers of the hippocampus make it possible to suggest a link between the
improvements in training and the histological structure of the hippocampus. This possibility,
which can be confirmed by further studies, is presented here.

Title
Ginkgo biloba extract (EGb 761): inhibitory effect on nitric oxide production in the
macrophage cell line RAW 264.7.
Author
Kobuchi H; Droy Lefaix MT; Christen Y; Packer L
Source
Biochem Pharmacol, 1997 Mar, 53:6, 897-903
Abstract
The present study was conducted to evaluate the effect of Ginkgo biloba extract (EGb 761)
on the synthesis of nitric oxide (NO) induced by lipopolysaccharide (LPS) plus
interferon-gamma (IFN-gamma) in the mouse macrophage cell line RAW 264.7. EGb 761
inhibited nitrite and nitrate production, taken as an index for NO, in a
concentration-dependent fashion. The IC50 for inhibition of nitrite production by activated
macrophages was about 100 micrograms/mL EGb 761. The inducible NO synthase (iNOS)
enzyme activity of cytosolic preparations from activated RAW 264.7 cells was inhibited by
treatment with EGb 761. In addition, reverse transcription-polymerase chain reaction
(RT-PCR) analysis revealed that the expression of iNOS mRNA in activated macrophages
was suppressed by high concentrations of EGb 761. However, NF-kappa B DNA binding
activity induced by activation with LPS/IFN-gamma was not inhibited by EGb 761. These
findings indicate that not only does EGb 761 directly act as an NO scavenger but also that it
inhibits NO production in LPS/IFN-gamma-activated macrophages by concomitant
inhibition of induction of iNOS mRNA and the enzyme activity of iNOS. Thus, EGb 761
may act as a potent inhibitor of NO production under tissue-damaging inflammatory
conditions.

Title
The bioavailability of ginkgolides in Ginkgo biloba extracts.
Author
Li CL; Wong YY
Source
Planta Med, 1997 Dec, 63:6, 563-5
Abstract
A new Ginkgo biloba leaf extract, BioGinkgo 27/7, was prepared using a method that
enriches ginkgolide B. The bioavailability of ginkgolides in these extracts was assessed in
rabbits in comparison with a commercially available standardized 24/6 extract. It was found
that, after a single dose, a higher concentration of ginkgolides was maintained for a longer
period of time with these extracts than was found with commercial extract prepared by
existing methods.

Title
Inhibition of human sperm motility by specific herbs used in alternative medicine.
Author
Ondrizek RR; Chan PJ; Patton WC; King A
Source
J Assist Reprod Genet, 1999 Feb, 16:2, 87-91
Abstract
PURPOSE: Our purpose was to analyze sperm motility parameters in the presence of
herbs. METHODS: Washed sperm were incubated in either saw-palmetto (Serenoa repens,
Permixon Sabal serrulatum), echinacea purpura, ginkgo biloba, St. John's wort (Hypericum
perforatum), or control medium. Parameters were measured on a Hamilton-Thorn analyzer
after 1, 4, 24, and 48 hr at 37 degrees C. RESULTS: Sperm motility was inhibited at the
high concentration (0.6 mg/mL) of St. John's wort. Curvilinear velocities and beat cross
frequencies also decreased, but not hyperactivation. High-concentration saw-palmetto,
echinacea, or gikgo inhibited motility at 24 and 48 hr. CONCLUSIONS: A potent inhibition
of sperm motility was seen in St. John's wort unrelated to changes in pH. Furthermore,
sperm viability was compromised in St. John's wort, suggesting a spermicidal effect.
Metabolic changes were observed in saw-palmetto-treated sperm. High-concentration
echinacea purpura interfered with sperm enzymes. Ginkgo did not have an antioxidant effect
on sperm motility.