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PubMed2005

EST analysis in Ginkgo biloba: an assessment of conserved developmental regulators and gymnosperm specific genes.

BACKGROUND: Ginkgo biloba L. is the only surviving member of one of the oldest living seed plant groups with medicinal, spiritual and horticultural importance worldwide. As an evolutionary relic, it displays many characters found in the early, extinct seed plants and extant cycads. To establish a molecular base to understand the evolution of seeds and pollen, we created a cDNA library and EST dataset from the reproductive structures of male (microsporangiate), female (megasporangiate), and vegetative organs (leaves) of Ginkgo biloba. RESULTS: RNA from newly emerged male and female reproductive organs and immature leaves was used to create three distinct cDNA libraries from which 6,434 ESTs were generated. These 6,434 ESTs from Ginkgo biloba were clustered into 3,830 unigenes. A comparison of our Ginkgo unigene set against the fully annotated genomes of rice and Arabidopsis, and all available ESTs in Genbank revealed that 256 Ginkgo unigenes match only genes among the gymnosperms and non-seed plants--many with multiple matches to genes in non-angiosperm plants. Conversely, another group of unigenes in Gingko had highly significant homology to transcription factors in angiosperms involved in development, including MADS box genes as well as post-transcriptional regulators. Several of the conserved developmental genes found in Ginkgo had top BLAST homology to cycad genes. We also note here the presence of ESTs in G. biloba similar to genes that to date have only been found in gymnosperms and an additional 22 Ginkgo genes common only to genes from cycads. CONCLUSION: Our analysis of an EST dataset from G. biloba revealed genes potentially unique to gymnosperms. Many of these genes showed homology to fully sequenced clones from our cycad EST dataset found in common only with gymnosperms. Other Ginkgo ESTs are similar to developmental regulators in higher plants. This work sets the stage for future studies on Ginkgo to better understand seed and pollen evolution, and to resolve the ambiguous phylogenetic relationship of G. biloba among the gymnosperms.

Contig Mapping↗
PubMed2003

Quantitative analysis of bilobalide and ginkgolides from Ginkgo biloba leaves and Ginkgo products using (1)H-NMR.

1H-NMR spectrometry was applied to the quantitative analysis of the bilobalide, ginkgolides A, B, and C in Ginkgo biloba leaves and six kinds of commercial Ginkgo products without any chromatographic purification. The experiment was performed by the analysis of each singlet H-12, which were well separated in the range of delta 6.0-7.0 in the (1)H-NMR spectrum. However, the H-12 protons of bilobalide and ginkgolides may have overlapped with H-6 or H-8 protons of the Ginkgo flavonoids. Therefore, the optimum (1)H-NMR solvent for the analysis of the compound was selected through the evaluation of solvent effects on the resolution of these signals from the compounds. Acetone-d(6)-benzene-d(6) (50 : 50) was found to be the best one among the solvents evaluated. The quantity of the compounds was calculated by the relative ratio of the intensity of each compound to the known amount of internal standard (25 microgram), phloroglucinol. This method allows rapid and simple quantitation of underivatized bilobalide and ginkgolides in 5 min without any pre-purification steps.

Cyclopentanes↗
PubMed2003

Hemodynamic and electrocardiographic effects of short-term Ginkgo biloba.

OBJECTIVE: To evaluate the immediate and short-term hemodynamic and electrocardiographic effects of Ginkgo biloba (ginkgo). METHODS: Healthy volunteers were randomized to receive ginkgo 120 mg or placebo twice daily for 7 days in this prospective, double blind trial. After at least a 7-day washout period, subjects were crossed over to an additional 7 days of alternate therapy. Blood pressure, heart rate, and 12-lead electrocardiograms were evaluated immediately before (baseline), and at 1, 3, and 5 hours after observed ingestion of study drug on days 1 and 7 of therapy. Electrocardiographic parameters (P wave and QRS complex duration; PR, QT, and QTc intervals) were measured in lead II by a blinded investigator. RESULTS: Ginkgo had no effect on any of the evaluated electrocardiographic parameters at any time point on days 1 or 7. Additionally, no changes in heart rate or systolic and diastolic blood pressure were found between the groups at any time point on any evaluative day. CONCLUSIONS: Commonly used doses of Ginkgo biloba do not have any immediate or short-term effects on blood pressure, heart rate, or electrocardiographic variables in young, healthy volunteers.

Adult↗
PubMed2003

Therapeutic mechanism of ginkgo biloba exocarp polysaccharides on gastric cancer.

AIM: To study the therapeutic mechanism of Ginkgo biloba exocarp polysaccharides (GBEP) on gastric cancer. METHODS: Thirty patients with gastric cancer were treated with oral GBEP capsules. The area of tumors was measured by electron gastroscope before and after treatment, then the inhibitory and effective rates were calculated. The ultrastructures of tumor cells were examined by transmissional electron microscope. Cell culture, MTT, flow cytometry were performed to observe proliferation, apoptosis and changes of relevant gene expression of human gastric cancer SGC-7901 cells. RESULTS: Compared with the statement before treatment, GBEP capsules could reduce the area of tumors, and the effective rate was 73.4%. Ultrastructural changes of the cells indicated that GBEP could induce apoptosis and differentiation in tumor cells of patients with gastric cancer. GBEP could inhibit the growth of human gastric cancer SGC-7901 cells following 24-72 h treatment in vitro at 10-320 mg/L, which was dose- and time-dependent. GBEP was able to elevate the apoptosis rate and expression of c-fos gene, but reduce the expression of c-myc and bcl-2 genes also in a dose-dependent manner. CONCLUSION: The therapeutic mechanism of GBEP on human gastric cancer may relate to its effects on the expression of c-myc, bcl-2 and c-fos genes, which can inhibit proliferation and induce apoptosis and differentiation of tumor cells.

Administration, Oral↗
PubMedDate not supplied

[Cerebrovascular and renal actions of bilobil and its effect on the metal ligand homeostasis (clinico-experimental study].

The tests on rats with common carotid artery occlusion showed that bilobil increases the cerebral blood flow and decreases brain edema, thus decreasing the loss of experimental animals. The drug also increases the blood circulation and improves the excretory function of kidneys. Under clinical conditions, bilobil increases the cerebral blood flow, normalizes the metal ligand homeostasis, and improves the antioxidant status in children with early forms of cerebrovascular disease (neurocirculate distonia) and attention deficit hyperactivity syndrome.

Adolescent↗
PubMed2003

[Ginkgo flavones in in vitro metabolism and its clinical application].

AIM: To develop a method for assaying Ginkgo flavones in rat hepatical microsome. METHODS: Quercetin, isorhamnetin and keampferol were added to microsome incubate and incubated for a given time then extracted with ether-acetone. After evaporated, the residue was reconstituted with 100 microL of phosphate buffer solution (pH 2.0)-tetrahydrofuran-methanol-isopropanol (60:15:10:20). An aliquot of 20 microL was injected into the HPLC system. According to the result of estimate by means of HPLC, the results of metabolism of Ginkgo flavones in different conditions was compared. RESULTS: The assay was linear over the rang of 0.2-8 mg.L-1 for Ginkgo flavones. The limit of quantification was 0.1 mg.L-1 (n = 3). The recoveries of three components of Ginkgo flavones were 99.9%-113.8% for quercetin (RSD < 0.8%), 100.8%-117.3% for isorhamnetin (RSD < 1.9%) and 100.7%-116.5% for keampferol (RSD < 1.03%, n = 5). CONCLUSION: The method is simple, fast and accurate. It can be used for investigation of the metabolism of Ginkgo flavones.

Animals↗
PubMed2000

Oxidase activity in lignifying xylem of a taxonomically diverse range of trees: identification of a conifer laccase.

In a diverse taxonomic range of tree species, including representative species of ancient families of angiosperms (Magnolia x soulangiana Soul.-Bod.) and gymnosperms (Ginkgo biloba L.), oxidase activity was associated with cell walls of developing xylem and was enriched in extracts of cell wall-associated glycoproteins. In all species where oxidase activity was detected histochemically, it was expressed in cell walls of lignifying, differentiating xylem cells and was absent from old wood, cambium and phloem, suggesting that oxidases have a conservative role in lignification of tree xylem. An oxidase from the developing xylem of Picea sitchensis (Bong) Carr. (Sitka spruce) was partially purified by a combination of lectin affinity and immobilized metal ion affinity chromatography. A portion of the total oxidase activity had high affinity for immobilized zinc ions and this feature allowed it to be separated from the bulk of oxidase activity. Two polypeptides that could have been responsible for the bound oxidase activity were enriched by this procedure. The smaller polypeptide of Mr approximately 73 kDa yielded an N-terminal amino-acid sequence that was homologous to laccase-like polyphenol oxidases (E.C. 1.10.3.2) from loblolly pine (Pinus taeda L.), poplar (Populus euramericana (Dode) Guinier) and Arabidopsis. The larger polypeptide (Mr approximately 77 kDa) yielded an N-terminal amino-acid sequence that was homologous with a range of plant subtilisin-like serine proteinases. The roles of oxidase and proteinase activities in developing xylem are discussed.

Cycadopsida↗
PubMed2002

Protective effect of Gingko biloba extract against doxorubicin-induced cardiotoxicity in mice.

Doxorubicin (DXR) causes dose dependent cardiotoxicity in experimental animals and in humans. In chronic doxorubicin cardiotoxicity model mice, the role of G. biloba extract (Gbe) which has an antioxidant property, was investigated. Doxorubicin treated animals showed higher mortality (68%), increased ascites, marked bradycardia, prolongation of ST and QT intervals and widening of QRS complex. Myocardial SOD and glutathione peroxidase activity were decreased and lipid peroxidation was increased. Ultrastructure of heart of DXR treated animals showed loss of myofibrils, swelling of mitochondria, vacuolization of mitochondria. G. biloba extract significantly protected the mice from cardiotoxic effects of doxorubicin as evidenced by lowered mortality, ascites, myocardial lipid peroxidation, normalization of antioxidant enzymes, reversal of ECG changes and minimal ultrastructural damage of the heart. The results indicate that administration of G. biloba extract protected mice from doxorubicin-induced cardiotoxicity.

Animals↗
PubMed2004

[HPLC fingerprint of the tablets of Ginkgo biloba L].

OBJECTIVE: To establish the method for determination of the fingerprint of tablets of Ginkgo biloba L. METHODS: HPLC-DAD was used to determine the constituents in tablets. Diamonsil C18(200 mm x 4.6 mm, 5 microm) was used as analysis column and acetonitrile/KH(2)PO(4) as mobile phase with gradient elution. The column temperature was at 24 degree. The profile of chemical constituents in control sample and tablets obtained from the chromatograms were analyzed by similarity software. RESULT: The method developed for components analysis of the standard extracts was linear within certain concentration (r>0.999). There was no difference between the fingerprints of 3 batches of products. The fingerprints of tablets and the extract showed a good similarity(>0.965). CONCLUSION: This method is accurate simple and can be used for the quality control of Ginkgo biloba L. preparations.

Chromatography, High Pressure Liquid↗
PubMed2004

Rapid analysis of 4-O-methylpyridoxine in the serum of patients with Ginkgo biloba seed poisoning by ion-pair high-performance liquid chromatography.

We have established a new method of HPLC analysis for the rapid separation from human serum and the quantification of 4-O-methylpyridoxine (MPN), which is contained in Ginkgo biloba seeds, and which, when consumed in large amounts, causes vomiting and convulsions. As a result of using IPCC-MS3 (GL Science, Tokyo, Japan), an ion-pair reagent, in the mobile phase, we succeeded in separating MPN in the deproteinized serum sample which was introduced directly onto the reverse-phase HPLC column. For the calibration curve of MPN standard solution, prepared with fluorescence detection at an excitation wavelength of 290 nm and an emission wavelength of 400 nm, a good linear relationship was obtained within the HPLC injection range of 10 ng-10 pg (in terms of the injected sample concentration, range: 1.0 microg/ml-1 ng/ml), allowing the detection of minute amounts, with the limit of detection (concentration of injected sample: 500 pg/ml) being 5 pg. In addition, when MPN solution was added to human reference serum to give a concentration of 0.002 microg/ml, the mean recovery rate was 92.5%, with RSD=7.09% (n=5). The time required for one analysis using this method is approximately 30 min, and thus it offers the advantages of greater speed and superior analytical sensitivity over the conventional methods, which require solid-phase extraction. We employed our new method to determine both the serum levels of MPN in 5 patients with Ginkgo biloba seed poisoning and the levels of free-form MPN in such seeds obtained in 8 regions of Japan.

Adult↗
PubMed2000

Electrospray characterization of selected medicinal plant extracts.

Extracts of selected medicinal plants were examined by electrospray mass spectrometry (ESI-MS). This technique allowed identification of the main components of each extract, thereby providing a typical finger-print of the examined plants. More specifically, anthocyanins (Vaccinium myrtillus), isoflavones (Glycine max, soybean), flavonol-glycosides and terpenes (Ginkgo biloba), triterpenes (Centella asiatica), caffeoyl-quinic acids (Cynara scolymus, artichoke), ginsenosides (Panax ginseng), catechins (Camellia sinensis, green tea) and flavones and flavanones (Propolis) were detected rapidly at levels in the range of 0.1-1 microg/ml, using 0.2-1 mg/ml of each medicinal plant extract.

Plant Extracts↗
PubMed1999

Therapeutic value of Ginkgo biloba in reducing symptoms of decline in mental function.

The Chinese tree Ginkgo biloba or "maiden hair tree" is extensively cultivated for the exploitation of the medicinal properties of its leaves. From these, a well-defined extract designated "EGb 761" has been developed, which was commercialized initially as Tanakan, Tebonin and Rokin; a similar product, Kaveri (LI 3170), also exists. The major therapeutic applications for these products are "cerebral insufficiency", other cerebral disorders, neurosensory problems and peripheral circulatory disturbances. Four primary concepts of action have been proposed to explain the pharmacotherapeutic benefits of EGb761; these are: vasoregulatory, cognition-enhancing, stress-alleviating, and gene-regulatory. These actions are believed to be realized through the principal active ingredients, flavonoids and the terpenoids ginkgolides and bilobalide acting simultaneously in concert, combination and synergy, so-called polyvalent action. It has been proposed that EGb761 may improve the memory of healthy volunteers, and in an assessment of [corrected] forty clinical studies, it was reported that Ginkgo was able to improve the twelve different symptoms comprising 'cerebral insufficiency', all of which are manifest in the elderly. These were supported in a second major study, using LI1370. However, in both instances, the evidence was largely based upon the results of self-assessment questionnaires. Latterly, in a large double blind study of men and women with the diagnosis of uncomplicated dementia who were administered Ginkgo for a year, a further positive outcome was claimed. In this study, patients were tested using ADAS-cog, GERRI and CGIC. It is suggested that whilst these different outcomes are compatible with (but do not affirm) a clinical benefit resulting from the use of Ginkgo, the application of a more objective system of assessment would be able to provide firm proof. It is proposed, therefore, that an objective, computer-based testing system for assessment of clinical improvement in volunteers and patients administered Ginkgo (such as CANTAB) would provide the convincing evidence currently being sought by patients, carers, physicians, legislators and the pharmaceutical industry.

Clinical Trials as Topic↗
PubMed2004

Estrogen bioassay of ginseng extract and ArginMax, a nutritional supplement for the enhancement of female sexual function.

PURPOSE: To determine whether ArginMax (The Daily Wellness Co., Sunnyvale, CA) or the Panax ginseng extract it contains has any estrogenic activity. ArginMax for Women, a nutritional supplement for optimization of sexual health, contains L-arginine, ginseng, ginkgo, damiana, multivitamins, and minerals. METHODS: A human endometrial adenocarcinoma cell line, Ishikawa, which contains an alkaline phosphatase (AP) enzyme sensitive to estrogen stimulation, was used in a bioassay to determine whether Panax ginseng or ArginMax contained estrogenic components. RESULTS: Neither ArginMax nor Panax ginseng stimulated AP at any of the concentrations tested. CONCLUSIONS: No estrogenic activity was evident in the sample of Panax ginseng extract tested or in a sample of ArginMax containing this extract in combination with other ingredients.

Adenocarcinoma↗
PubMedDate not supplied

Determination of flavonol aglycones in Ginkgo biloba dietary supplement crude materials and finished products by high-performance liquid chromatography: single laboratory validation.

A single laboratory validation (SLV) was completed for a method to determine the flavonol aglycones quercetin, kaempferol, and isorhamnetin in Ginkgo biloba products. The method calculates total glycosides based on these aglycones formed following acid hydrolysis. Nine matrixes were chosen for the study, including crude leaf material, standardized dry powder extract, single and multiple entity finished products, and ethanol and glycerol tinctures. For the 9 matrixes evaluated as part of this SLV, the method appeared to be selective and specific, with no observed interferences. The simplified 60 min oven heating hydrolysis procedure was effective for each of the matrixes studied, with no apparent or consistent differences between 60, 75, and 90 min at 90 degrees C. A Youden ruggedness trial testing 7 factors with the potential to affect quantitative results showed that 2 factors (volume hydrolyzed and test sample extraction/hydrolysis weight) were the most important parameters for control during sample preparation. The method performed well in terms of precision, with 4 matrixes tested in triplicate over a 3-day period showing an overall repeatability (relative standard deviation, RSD) of 2.3%. Analysis of variance testing at alpha = 0.05 showed no significant differences among the within- or between-group sources of variation, although comparisons of within-day (Sw), between-day (Sb), and total (St) precision showed that a majority of the standard deviation came from within-day determinations for all matrixes. Accuracy testing at 2 levels (approximately 30 and 90% of the determined concentrations in standardized dry powder extract) from 2 complex negative control matrixes showed an overall 96% recovery and RSD of 1.0% for the high spike, and 94% recovery and RSD of 2.5% for the low spike. HorRat scores were within the limits for performance acceptability, ranging from 0.4 to 1.3. Based on the performance results presented herein, it is recommended that this method progress to the collaborative laboratory trial.

Calibration↗
PubMed2004

The evaluation of nitric oxide scavenging activity of certain herbal formulations in vitro: a preliminary study.

The nitric oxide (NO) scavenging activities of traditional polyherbal drugs like abana, chyavanaprasha, geriforte, septilin, mentat and triphala were examined using sodium nitroprusside as a NO donor in vitro. All the drugs tested demonstrated direct scavenging of NO and were superior to Gingko biloba, which was used as a positive control. The extracts of various polyherbal drugs exhibited dose-dependent NO scavenging activities and the potency was in the following order: abana > chyavanaprasha > triphala > geriforte > septilin > mentat > Gingko biloba. The present results suggest that the traditional Indian polyherbal crude drugs may be potent and novel therapeutic agents for scavenging of NO, and thereby inhibit the pathological conditions caused by excessive generation of NO and its oxidation product, peroxynitrite. These findings may also help to explain, at least in part, the pharmacological activities like rejuvenating, adaptogenic, anti-infection, anti-inflammatory, cardioprotective and neuroprotective activities of these traditional, clinically used non toxic drugs.

Free Radical Scavengers↗
PubMed2004

Prolyl endopeptidase inhibitors from the leaves of Ginkgo biloba.

Prolyl endopeptidase (PEP, EC 3.4.21.26) hydrolyzes proline-containing neuropeptides, such as vasopressin, substance P, and thyrotropin-releasing hormone (TRH), and is suggested to participate in learning and memory processes. Ginkgo biloba leaves, upon examination for anti-amnestic constituents as new types of PEP inhibitors, showed significant PEP inhibition. PEP activity-guided fractionation and column chromatography of the MeOH extracts of G. biloba leaves resulted in the isolation of 6-(8'Z-pentadecenyl)salicylic acid (1) and 6-(10'Z-heptadecenyl)salicylic acid (2). The kinetic study indicated that compounds 1 and 2 are non-competitive inhibitors of prolyl endopeptidase with Ki values of 0.87 and 0.80 microM, respectively.

Dose-Response Relationship, Drug↗