Ginkgo biloba extract alleviates fatty liver hemorrhagic syndrome in laying hens via reshaping gut microbiota

Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver disease.However,the role of GBE in alleviating fatty liver hemorrhagic syndrome(FLHS)in laying hens and the underlying mechanisms remain to be elucidated.Here,we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut microbiota.Results The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet(HFD)-induced FLHS laying hen model by decreasing the levels of TG,TC,ALT and ALP.The lipid accumulation and pathological score of liver were also relieved after GBE treatment.Moreover,GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH,SOD,T-AOC,GSH-PX and reducing MDA,and downregulated the expression of genes related to lipid synthesis(FAS,LXRα,GPAT1,PPARγand Ch REBP1)and inflammatory cytokines(TNF-α,IL-6,TLR4 and NF-κB)in the liver.Microbial profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota,particularly elevated the abundance of Megasphaera in the cecum.Meanwhile,targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs,acetate and propionate,which were positively correlated with the GBE-enriched gut microbiota.Finally,we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation(FMT).Conclusions We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut microbiota.Our findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.

Efficacy and Safety of Ginkgo Biloba Tincture(银杏叶酊) Combined with Conventional Medication in the Treatment of Cerebral Infarction: Systematic Review and Meta-analysis

Objective:To analyze the efficacy and safety of Ginkgo biloba tincture combined with conventional medication in the treatment of cerebral infarction by systematic evaluation.Methods:Searched the randomized controlled trials of Ginkgo biloba tincture in treating cerebral infarction.English literatures were searched from PubMed,EMbase,Cochrane Library and Web of Science,and Chinese literatures were searched from Chinese Biomedical Literature Database(CBM),China National Knowledge Infrastructure(CNKI),China Science and Technology Journal Database(VIP)and Wanfang Medical Database.At the same time,we searched dissertations,conference papers,and found relevant unpublished research results reports.Literature quality was evaluated using a"bias risk assessment tool"and Meta-analysis using RevMan 5.4 software(from the Cochrane Collaboration).A total of 29 literatures were retrieved,and finally 4 literatures meeting the standards were included.There were 455 samples involved,including 244 cases in the experimental group and 211 cases in the control group.Results:①Effectiveness analysis:The total effective rate of Ginkgo biloba tincture combined with routine treatment was better than that of the control group[RR=1.26,95%CI(1.07,1.47),P=0.005].The hematocrit of Ginkgo biloba tincture combined with conventional treatment was significantly better than that of conventional treatment alone(P<0.05),The neurological deficits of Ginkgo biloba tincture combined with routine therapy was significantly improved(P<0.05).After Ginkgo biloba tincture combined with conventional therapy,the scores of mini-mental state examination(MMSE),activity daily living scale(ADL)and MOSSF-36 quality of life scale were significantly better than those of the control group(P<0.05).②Safety analysis:3 articles reported the safety of medication.There was no obvious change in blood routine,liver and kidney function results and no adverse reactions in the experimental group and the control group.Conclusion:The above results indicated that Ginkgo biloba tincture combined with conventional treatment can improve the total effective rate of patients with cerebral infarction,and it is safe and has no adverse reactions.However,the number of literatures included in this study is small,and the quality of controlled trials is not good.It is still necessary to adopt clinical controlled trials with reasonable design,outcome indicators in line with international social norms and large sample content to further improve the evidence level of clinical research.

孑遗植物银杏(Ginkgo biloba L.)伴性光合生理特征与进化生态

银杏类是一类古老的雌雄异株植物,目前仅存单科单属。由于银杏在系统发育等方面的独特地位,吸引了科学家从不同方面进行了广泛的研究。在适宜的条件下,测定了生长在野外环境下的成年银杏的雌雄个体的光合特性。研究结果表明,银杏的雌雄植株对光具有相同的表现趋势,光饱和点,光补偿点,光下呼吸速率等均没有明显差异。但是雌性银杏的净光合速率明显大于雄性银杏的净光合速率。这种差异可能与雌性个体在繁衍后代时需要投入更多的能量有关。研究也表明,在与其它的裸子植物和被子植物比较时,银杏的光合能力并没有明显的弱势,因此光合能力可能并不是银杏在第三纪分布受限的直接原因.

CO_2浓度倍增对城市银杏(Ginkgo biloba)叶片膜脂过氧化与抗氧化酶活性的影响

以生长在沈阳市区内的银杏为试材,使用开顶箱模拟法对倍增CO2浓度(700μmolmol-1)和正常空气CO2浓度(≈350μmolmol-1)条件下银杏生长参数,超氧阴离子自由基(O2-.)产生速率,丙二醛(MDA)含量,抗坏血酸(ASA)含量,超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)及谷胱甘肽还原酶(GR)活性动态变化进行分析,探讨高浓度CO2对银杏膜脂过氧化与抗氧化酶活性的影响。结果表明,在短期(60d)内CO2浓度倍增使银杏细胞内O2-.产生速率与H2O2含量减少,而ASA含量与SOD、APX、GR活性升高。与对照相比,大多数测定显示出显著差别。但较长期(70d以上)CO2浓度倍增处理则使试验结果发生逆转,活性氧O2-.产生速率略有升高,SOD、APX、GR活性略有下降,ASA含量仍略高于对照(但与对照相比差异并不显著),长期CO2浓度倍增处理可能使试验结果发生逆转。

银杏(Ginkgo biloba)叶表皮特征及其气孔的发育

通过光学显微镜和扫描电子显微镜 ,对离析和未离析的、成熟的和刚开始发育的银杏叶表皮进行了研究。表皮基本特征 :两面生气孔型 ,但气孔主要分布在下表皮 ,上表皮气孔的数目和分布因个体而异 ;气孔器为单唇单环式 ,围绕每个气孔的副卫细胞数目多为 5～ 6个 ;副卫细胞的平周壁明显加厚 ,具乳突状突起 ,拱盖着下陷的保卫细胞 ;偶有双气孔发生 ;上表皮厚于下表皮 ;表皮细胞可明显分为叶脉区和脉间区。角质外蜡质层 :在高倍扫描电子显微镜下 ,管状的蜡质晶体交错覆盖在叶片的外表面 ,还观察到有些管状的蜡质晶体呈分叉状态。气孔的发育 :通过我们的观察 ,认为银杏气孔的发生属于典型的周源型 ,即副卫细胞与保卫细胞各自发生于不同的母细胞 ,而不是前人报道的中———周型起源。

孑遗植物银杏(Ginkgo biloba L.)雌雄株水分生理特征初步研究

[目的]研究银杏雌雄株在水分生理上的差异，探讨其水分利用策略，以及在进化过程中的重要作用。[方法]对银杏雌雄株的树干液流（sap flow）、气孔导度（Gs）、蒸腾速率（Tr）以及水分利用效率（WUE）进行对比研究。[结果]雌雄银杏的液流昼夜进程具有相似的规律，且白天雌雄株液流基本相同，夜间雄株液流大于雌株；不同性别银杏的丹和岱同样呈现为早晚高、午间低的曲线趋势，早晚雌株有比雄株更高的Tr和Gs，但中午11：00-14：00之间雌株的值低于雄株；雌雄银杏的WUE曲线变化趋势相似，但雌株的平均水分利用效率略小于雄株。[结论]与其他伴性植物比较分析得知，不同性别银杏的水分生理有较强的趋同特征。这可能是在长期进化的压力下，雌雄异株植物的一种生存策略。

A ginkgo biloba extract promotes proliferation of endogenous neural stem cells in vascular dementia rats

The ginkgo biloba extract EGb761 improves memory loss and cognitive impairments in patients with senile dementia. It also promotes proliferation of neural stem cells in the subventricular zone in Parkinson＇s disease model mice and in the hippocampal zone of young epileptic rats. However, it remains unclear whether EGb761 enhances proliferation of endogenous neural stem cells in the brain of rats with vascular dementia. In this study, a vascular dementia model was established by repeatedly clipping and reperfusing the bilateral common carotid arteries of rats in combination with an intraperitoneal injection of a sodium nitroprusside solution. Seven days after establishing the model, rats were intragastrically given EGb761 at 50 mg/kg per day. Learning and memory abilities were assessed using the Morris water maze and proliferation of endogenous neural stem cells in the subventricular zone and dentate gyrus were labeled by 5-bromo-2-deoxyuridine immunofluorescence in all rats at 15 days, and 1, 2, and 4 months after model establishment. The escape latencies in Morris water maze tests of rats with vascular dementia after EGb761 treatment were significantly shorter than the model group. Immunofluorescence staining showed that the number and proliferation of 5-bromo-2-deoxyuridine-positive cells in the subventricular zone and dentate gyrus of the EGb761-treated group were significantly higher than in the model group. These experimental findings suggest that EGb761 enhances proliferation of neural stem cells in the subventricular zone and dentate gyrus, and significantly improves learning and memory in rats with vascular dementia.

Experimental Study on Inhibition of Neuronal Toxical Effect of Levodopa by Ginkgo Biloba Extract on Parkinson Disease in Rats

In order to observe neuronal toxical effect of Levodopa and investigate if using Levodopa together with Ginkgo Bilobar Extract (EGb) would be an workable method to treat Parkinson disease, rat models of Parkinson disease (PD) were made by injecting 6-OHDA stereotaxically to right side of the mesencephic ventral tegmental area (VTA) and substantia nigra pars compacta (SNc). Rotational behavioral observation, TUNEL, immunocytochemistry, Nissl's body staining were performed to measure the difference between group treated by Levodopa (50 mg/kg every day for 3 days, 5 days, 7 days, L-dopa group) and group treated by Levodopa combined with EGb (100 mg/ kg every day, E-D group). The results showed that in the L-dopa group, the numbers of apoptosis of substantial nigra, rings of rotational behavior were more than those in the E-D group (P<0. 05). The numbers of Nissl's cells in L-dopa group were fewer than in E-D group (P<0. 05). The results suggested that Levodopa had neur toxic effect and EGb may decrease the toxicity of levodopa. The combined use of EGb with Levodopa may be a workable method to treat PD and may be better than using Levodopa alone.

Changes of main secondary metabolites in leaves of Ginkgo biloba in response to ozone fumigation

To investigate the effect of elevated 03 on the accumulation of main secondary metabolites in leaves of Ginkgo biloba L., four-year- old trees were exposed in open-top chambers with ambient air and the air with twice ambient 03 concentration in Shenyang in 2006. Elevated 03 increased the concentrations of terpenes, but decreased the concentrations of phenolics in G. biloba leaves. The results showed that secondary compounds from G. biloba leaves responded to the elevated 03 exposure in a different way when compared to previous studies which showed elevated 03 increased the concentrations of phenolics but had no effect on the terpenes in leaves of other deciduous trees. Furthermore, reduced synthesis of phenolics may decrease the resistance of G. biloba to 03 and other environmental factors. On the other hand, the induced synthesis of terpenes may enhance the antioxidant abilities in G. biloba leaves at the end of 03 fumigation.

Identification and Purification of an Allergic Glycoprotein from Ginkgo biloba Kernel

Glycoprotein from Ginkgo biloba kernel may be allergic. In this paper, the allergic proteins were identified with Western blotting, and the 32 kDa glycoprotein was purified with ion exchange chromatography and gel chromatography. With Western blotting, there were 3 allergic proteins with molecular weight 21, 32, and 36 kDa. With SDS-PAGE analysis and measurements of the protein and sugar contents, the isolation and purification technology of 32 kDa was confirmed. Ginkgo crude protein extract was precipitated with ammonium sulphate （saturation gradient： 40-80%）. The precipitate was purified by chromatography with DEAE-cellulose 52, then chromatography with Sephadex G-200 and the target glycoprotein was finally obtained. The analysis results showed the molecule of the glycoprotein was 32.12 kDa and the ratio of protein to sugar was 20.56：1. In conclusion, the purification method could be used in preparation of the glycoprotein, and the study could provide a basis for the further research of the glycoprotein.

Extract of Ginkgo biloba promotes neuronal regeneration in the hippocampus after exposure to acrylamide

Previous studies have demonstrated a neuroprotective effect of extract of Ginkgo biloba against neuronal damage, but have mainly focused on antioxidation of extract of Ginkgo biloba. To date, limited studies have determined whether extrasct of Ginkgo biloba has a protective effect on neuronal damage. In the present study, acrylamide and 30, 60, and 120 mg/kg extract of Ginkgo biloba were administered for 4 weeks by gavage to establish mouse models. Our results showed that 30, 60, and 120 mg/kg extract of Ginkgo biloba effectively alleviated the abnormal gait of poisoned mice, and up-regulated protein expression levels of doublecortin（DCX）, brain-derived neurotrophic factor, and growth associated protein-43（GAP-43） in the hippocampus. Simultaneously, DCX-and GAP-43-immunoreactive cells increased. These findings suggest that extract of Ginkgo biloba can mitigate neurotoxicity induced by acrylamide, and thereby promote neuronal regeneration in the hippocampus of acrylamide-treated mice.

Ginkgo biloba leaf extract improves the cognitive abilities of rats with D-galactose induced dementia

Standardized Ginkgo biloba leaf extract has been used in clinical trials for its beneficial effects on brain func- tions, particularly in dementia. Substantial experimental evidences indicated that Ginkgo biloba leaf extract （EGB） protected neuronal cells from a variety of insults. We investigated the effect of EGB on cognitive ability and protein kinase B （PKB） activity in hippocampal neuronal cells of dementia model rats. Rats received an intra- peritoneal injection of D-galactose to induce dementia. Forty-eight Spraque-Dawley rats were randomly divided into six groups, including the control group, D-galactose group （Gal）, low-dose EGB group （EGB-L）, mid-dose EGB group （EGB-M）, high-dose EGB group （EGB-H） and treatment group. The EGB-L, EGB-M and EGB-H groups were administered with EGB and D-galactose simultaneously. Y-maze, cresyl violet staining, TUNEL assays and immunohistochemistry staining were performed to detect learning and memory abilities, morpho- logical changes in the hippocampus, neuronal apoptosis and the expressing level of phospho-PKB, respectively. Rats in the Gal group showed decreased abilities of learning and memory, and hippocampal pyramidal cell layer was damaged, while EGB administration improved learning and memory abilities. The Gal group exhibited many stained, condensed nuclei and micronuclei, either isolated or within the cytoplasm of cells （39.5 ± 1.4）. Apoptotic cells decreased in the groups of EGB-L （35.9±0.9）, EGB-M （16.8± 1.0） and EGB-H （10.1±0.8）, and there were statistical significances compared with the Gal group. Immunoreactivity of phospho-PKB was localized diffusely throughout the cytosol of cells in all groups, while the immunoreactivity of the Gal group was weak. EGB signifi- cantly attenuated learning and memory impairment in a dose-dependent manner, while it could decrease the nmber of TUNEL-positive cells, and increase the activity of PKB. Our results demonstrated that EGB attenuated memory impairment and cell apoptosis in galactose-induced dementia model rats by activating PKB.

CTAB-silica Method for DNA Extraction and Purification from Castanea mollissima and Ginkgo biloba

A new method CTAB-silica for DNA extraction and purification from the leaves and buds of Castanea mollissima and Ginkgo biloba was tested. The method is based on the silica-based purification protocol developed by Boom et al. (1990). By modifying the protocol, plant genome DNA could be extracted easily from dormant buds, mature leaves, and other parts of plant. Our results showed that the purified DNA was of high purity and could be analyzed by PCR. Furthermore, this CTAB-silica method took much less time for a successful DNA purification process compared to the traditional methods (CTAB and SDS). By our method, the suitable DNA can be extracted and purified from over 10 plant samples by one person in an hour.

The Effect of 2,5-hexanedione on Myelin Protein Zero Expression,and Its Mitigation Using Ginkgo Biloba Extract

Objective To investigate the role of myelin protein zero （P 0） in 2,5-hexanedione （2,5-HD）-induced peripheral nerve injury,and the protective effect of Ginkgo biloba extract （Egb761） on 2,5-HD-induced toxic peripheral neuropathy.Methods After 4 weeks of treatment with 2,5-HD at different doses （50,100,200,400 mg/kg） in rats,changes in the levels of P 0 in rat sciatic nerves was investigated,and the effect of Egb761 on 2,5-HD-induced toxic peripheral neuropathy was studied.Results The blood-nerve barrier （BNB） permeability of the sciatic nerve increased,and the expression of P 0 mRNA and P 0 protein decreased in a dose-dependent manner after treatment with 2,5-HD for 4 weeks.Pretreatment with Egb761 protected against BNB interruption,and inhibited P 0 mRNA and protein reduction during 2,5-HD treatment.Pretreatment with Egb761 significantly reduced loss of body weight （P0.01） and mitigated gait abnormalities （2.85±0.22） induced by 400 mg/kg 2,5-HD （P0.01）.It also reduced the signs of neurotoxicity induced by 2,5-HD.Conclusion 2,5-HD inhibited the expression of P 0 in a dose-dependent manner,and this may be an important mechanism by which toxic peripheral neuropathy is induced by 2,5-HD.Egb761 has a protective effect against 2,5-HD-induced peripheral neurotoxicity in rats.

Protective Effect of Ginkgo Biloba Leaf Extract on Learning and Memory Deficit Induced by Aluminum in Model Rats

Objective： To examine the protective effect of Ginkgo biloba leaf extract （GbE） on learning and memory deficit induced by aluminum chloride （AlCl3）, and explore its mechanisms. Methods： The rat models with learning and memory deficit were induced by administering via gastrogavage and drinking of AlCl3 solution. And the model rats were treated with GbE at the dose of 50, 100, 200 mg/kg every day for 2 months accompanied with drinking of AlCl3 solution, respectively. Their abilities of spatial learning and memory were tested by Morris water maze, and the acetylcholinesterase （ACHE） activity in serum was assayed with chemical method, the AChE expression in hippocampus was observed by immunohistochemistry assay, and then quantitative analysis was done by BI 2000 image analysis system. Results： Learning and memory deficit of rats could be induced by AlCl3 solution （P〈0.01）, and AChE expressions in rats hippocampus were increased （P〈0.01）; GbE ameliorated learning and memory deficit and reduced AChE expression in rats hippocampus in a dose-dependent manner, while GbE significantly increased serum AChE activity at the dose of 200 mg/kg each day （P〈0.05）. Conclusion： GbE can ameliorate learning and memory deficit induced by AlCl3, which may be due to its inhibition of the AChE expression in hippocampus.

Female Plant Types of Ginkgo biloba L. in China

Ginkgo biloba is a dioecious and unique species within Ginkgo family and Ginkgo genus, but it shows a big variability. From 1950s, resources of female plants in China were investigated and collected, and the seed anatomical structure and morphological characters at different development stages were observed. According to the shape, length, width and thickness of ovule bracket and seed stone, as well as the characteristics of both sides and top of the stone, the female plants of Ginkgo biloba have been divided into five types, long-stone, Buddha-finger, horse-bell, mume-stone and round-stone. In addition, the important cultivars belonging to different types were also determined. The stone weight, index of stone shape, and contents of dry matter, amylose, amylopectin, starch, rough protein, soluble sugar and hydrocyanic acid in seed kernel of each type were measured, and the qualities of seed stone were appraised, which lays a foundation for the improvement and utilization of female plant resources in Ginkgo biloba.

Protective effects of ginkgo biloba leaves extract on peroxide-induced oxidative stress damage in PC12 cells

BACKGROUND： Extracts of ginkgo biloba leaves （EGB） and its metabolites have been reported to enhance brain function and nerve behavior. It has also been hypothesized that they can protect neurons from oxidative stress. OBJECTIVE： To investigate protective effects of EGB on peroxide （H2O2）-induced oxidative stress damage in PC12 cells. DESIGN： Observational contrast study. SETTING： Department ofPathophysiology, Guangdong Pharmacological College. MATERIALS： EGB was provided by Xi＇an Fujie Biotechnological Development Company; 1640 culture medium, methylthiazolyl tetrazolium （MTT）, trypsin and dimathyl sulfoxide （DMSO） by Sigma Company; PC12 cell strain by Cell Center of Medical College of Zhongshan University; calf serum by Hangzhou Sijiqing Bioengineering Company; lactate dehydrogenase （LDH） kit by Nanjing Jiancheng Bioengineering Research Institute. METHODS： The experiment was carried out in Department of Cell Biology of Guangdong Pharmacological College from June to December 2005. ①Cell culture： PC12 cells were cultured in 1640 medium containing 200 g/L fetal calf serum. The cells were diluted to 1 × 10^7 L^-1 and washed every two days. Those cells were used to experiment until they grew in logarithm on solid wall. ② Grouping and intervention： PC12 cells （1 × 10^8L^-1） were plated in 96-well plates with the density of 200 μ L/hole and divided into three groups： normal control group （routinely adding media）, H2O2 group （treating with media and H2O2 for 20 hours） and EGB group （adding media, 100μmol/L EGB and 100 μmol/L H2O2）. ③ MTT assay： PC12 cells （1 × 10^8L^-1） were plated in 96-well plates and divided into three groups with 8 holes for each group. Under sterile condition, cells were added with 5 g/L MTT （100μL） and cultured for 4 hours. And then, 200 μ L DMSO fluid was added and shaken for 30 minutes until blue crystal products formed were dissolved soundly ④ Experimental evaluation： Absorbance （A） at 630 nm was measured and LDH activity was measured at the same time. MAIN OUTCOME MEASURES： Results of MTT assay and LDH activity. RESULTS： ① Results of MTT assay： A value was lower in the H2O2 group than that in the normal control group （P 〈 0.01）, while A value was higher in the EGB group than that in the H2O2 group （P 〈 0.01）. ② LDH activity： LDH activity was higher in the H2O2 group than that in the normal control group （P 〈 0.01 ）, while LDH activity was lower in the EGB group than that in the H2O2 group （P 〈 0.01）. CONCLUSION： EGB can inhibit H2O2-induced oxidative stress damage in PC12 cells possibly by preventing damage to the cell membrane.

Determination of the Flavonoids from Ginkgo Biloba Extract by High Performance Liquid Chromatography

HPLC method for analysis of the flavonoids from ginkgo biloba extract (GBE) was studied. By suitable selection of columns, symmetrical chromatographic peaks were obtained without using acidic modifier in the mobile phase, which can eliminate the time for cleaning the chromatographic system and simplify the analystic method for GBE. Experimental conditions: column: Hypersil BDS C18,5mm×4×250 mm; column temperature: 35C; mobile phase: 46% methanol-54% water; flow rate: 0.7 mL/min; detection wavelength: 360nm.

Neuroprotective effects of Ginkgo biloba dropping pills in Parkinson's disease

Parkinson's disease(PD) is the second most common neurodegenerative disease in the world;however,it lacks effective and safe treatments. Ginkgo biloba dropping pill(GBDP), a unique Chinese G. biloba leaf extract preparation, exhibits antioxidant and neuroprotective effects and has a potential as an alternative therapy for PD. Thus, the aims of this study were to evaluate the effects of GBDP in in vitro and in vivo PD models and to compare the chemical constituents and pharmacological activities of GBDP and the G. biloba extract EGb 761. Using liquid chromatography tandem-mass spectrometry, 46 GBDP constituents were identified. Principal component analysis identified differences in the chemical profiles of GBDP and EGb 761. A quantitative analysis of 12 constituents showed that GBDP had higher levels of several flavonoids and terpene trilactones than EGb 761, whereas EGb 761 had higher levels of organic acids.Moreover, we found that GBDP prevented 6-hydroxydopamine-induced dopaminergic neuron loss in zebrafish and improved cognitive impairment and neuronal damage in methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced PD mice. Although similar effects were observed after EGb 761 treatment,the neuroprotective effects were greater after GBDP treatment on several endpoints. In addition, in vitro results suggested that the Akt/GSK3β pathway may be involved in the neuroprotective effects of GBDP.These findings demonstrated that GBDP have potential neuroprotective effects in the treatment of PD.

Activity of Ginkgo biloba Extract and Quercetin on Thrombomodulin Expression and Tissue-type Plasminogen Activator Secretion by Human Umbilical Vein Endothelial Cells

Objective In order to investigate the pharmacological properties of Ginkgo biloba extract （GBE） on improving blood circulation, the regulating action of GBE and quercetin （a main flavonoid ingredient in GBE） on thrombomodulin （TM） expression and tissue-type plasminogen activator （t-PA） secretion was studied. Methods Using flow cytometer and gel image system respectively, we evaluated the TM expression and the t-PA secretion by human umbilical vein endothelial cells （HUVECs） in vitro. Results The increase of TM expression on HUVECs surface was induced by GBE rather than quercetin in a dose- and time-dependent manner. Both GBE and quercetin increased the t-PA release significantly. Conclusion The effect of GBE on improving blood circulation may be partly attributed to its promoting TM expression and t-PA secretion by endothelial ceils, and quercetin participated in the effect of GBE on t-PA secretion. However, the action of GBE on increasing TM expression needs further study.