野葛根和银杏叶提取物配伍复方制剂的抗氧化实验研究

目的 观察银杏叶复方制剂对老龄小鼠的抗氧化作用.方法 老龄小鼠40只,随机分成老龄对照组,银杏叶单方制剂组,银杏叶复方制剂高、低剂量组,每组10只.另10只标准体重小鼠作青年对照组.老龄对照组和青年对照组均给予等体积蒸馏水,各用药组连续灌胃给药10 d.末次给药后1 h,采血分离血清,检测超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量.结果 与老龄对照组比较,银杏叶复方制剂高、低剂量组和单方制剂组均可明显提高老龄小鼠血清中SOD活性,降低MDA含量.银杏叶复方制剂高剂量组提高SOD活性的强度大于低剂量组和单方制剂组(P<0.05).结论 银杏叶复方制剂具有抗氧化作用且呈现一定的量-效关系,处方中的银杏叶提取物与野葛根提取物成分具有一定的协同药效作用.     

银杏叶提取物抗兔氧化损伤作用实验研究

目的:进行银杏叶提取物对四氯化碳致兔氧化损伤的保护作用研究。方法:实验动物分为正常对照组(A)、损伤模型组(B)、药物Ⅰ组(C)、药物Ⅱ组(D),分别先静脉注射生理盐水(A、B),银杏叶提取物(C、D),再腹腔注射生理盐水(A)、四氯化碳(B、S、D);在4h(A、B、C)、24h(D)心脏去血液测定血清SOD、GSH-PX、GSH、活性氧、XOD等水平。结果:(1)与对照组比较,损伤模型组血活性氧、XOD等水平明显升高(P(0.05)。SOD、CAT、GSH-PX等酶水平明显降低(P(0.01),GSH无明显变化(P(0.05)。(2)药物Ⅰ组、药物Ⅱ组血活性氧、XOD等水平明显低于损伤模型组(P(0.05),药物Ⅱ组SOD、GSH-PX明显高于损伤模型组(P(0.05),血GSH无明显变化(P(0.05)。结论:银杏叶提取物具有消除自由基抗氧化损伤作用,其重要途径之一是降低血活性氧、XOD等水平和升高SOD、CAT、GSH-PX酶活性。     

银杏叶提取物对辐射损伤小鼠的保护作用

目的研究银杏叶提取物对60Co-γ射线辐射损伤小鼠的保护作用。方法采用健康小鼠作为实验对象,银杏叶提取物ig给药,使用60Co-γ作为辐射源制备辐射损伤模型,眼眶取血计数外周血白细胞和淋巴细胞数;取肝组织测定其蛋白质、MDA及SOD、GSH活性。结果银杏叶提取物能增加辐射小鼠白细胞、淋巴细胞数量,减轻辐射对肝脏合成功能的损伤,增加SOD、GSH活性,降低MDA量。结论银杏叶提取物对辐射损伤的小鼠具有保护作用,其保护机制与其抗氧化作用以及免疫影响有关。     

银杏叶提取物及其主要成分抗氧化作用的比较

目的:比较银杏叶提取物(EGb)及其主要成分(银杏黄酮,银杏帖内酯)的抗氧化作用.方法:用EGb、银杏黄酮和银杏帖内酯作用于细胞,Western-blot检测其对抗氧化酶GCLC的诱导作用;用相应的功能检测法测定EGb、银杏黄酮和银杏帖内酯在体外直接清除超氧阴离子及羟自由基、抑制大鼠红细胞溶血及大鼠肝组织的脂质过氧化的作用.结果:EGb和银杏黄酮可诱导抗氧化酶GCLC的表达,并能直接清除超氧阴离子及羟自由基、抑制大鼠红细胞溶血及大鼠肝组织的脂质过氧化,而银杏帖内酯无明显的抗氧化作用.EGb的这些抗氧化作用均强于银杏黄酮.结论:EGb抗氧化作用强于银杏黄酮,而银杏帖内酯没有明显的抗氧化作用.     

银杏叶提取物降血糖作用的实验研究

目的观察银杏叶提取物对糖尿病小鼠的降血糖作用。方法给断乳的小鼠饲喂高脂饲料,制备糖尿病模型,造模成功的小鼠随机分为给药组和模型组,外加空白对照组;给药组分别给予0.3,0.6,1.2 g/kg剂量的银杏叶提取物,模型组和空白组给予等体积的蒸馏水,给药1个月后测定小鼠的空腹血糖值,糖耐量以及血清MDA和SOD的含量。结果银杏叶提取物可以显著降低高血糖小鼠的空腹血糖值(P(0.01),降低血清MDA的含量,但是对高血糖小鼠的糖耐量的影响不大。结论银杏叶提取物可以降低糖尿病小鼠的血糖值。     

金鸡菊提取物体外抗氧化活性

目的:探讨金鸡菊提取物体外抗氧化活性。方法:采用分光光度法,测定金鸡菊提取物对羟基(OH)自由基、超氧阴离子(O 2-.)自由基及1,1-二苯基-2-苦肼基自由基(DPPH)的清除能力,通过多元线性回归分析,考察金鸡菊提取物含量及其体外抗氧化活性的相关性,并同维生素(VC)进行了比较。结果:金鸡菊提取物对.OH自由基,O 2-.自由基,DPPH自由基均有较好的清除作用,在供试质量浓度范围内(0.2～1.0 g.L-1)对各自由基的清除效率与金鸡菊提取物浓度有一定量效关系,当质量浓度达1.0 g.L-1,其中50%乙醇洗脱物对OH自由基、O 2-.自由基和DPPH自由基的清除率可达86.19%,97.90%和71.85%,且清除能力与Vc相当。结论:金鸡菊提取物具有显著的体外抗氧化作用。     

银杏叶和山楂叶的抗氧化作用

 目的：研究银杏叶、山楂叶提取物的抗氧化作用。方法：采用荧光法测定过氧化作用的产物丙二醛含量；分光光度法测定银杏叶、山楂叶提取物对氧自由基(H₂O₂，O₂)的抑制作用。结果：银杏叶(G)、山楂叶(H)的提取物能抑制小鼠肝匀浆在37℃温育下生成的丙二醛，抑制率G为68.5%，H为76.9%。抑制由邻苯三酚在pH8.4自氧化产生的O₂(与对照组相比,G:P＜0.01、H:P＜0.05)，并能降低由H2O2所致的血红蛋白氧化和红细胞的溶血作用(溶血率H₂O₂为10.9%，经G和H抗氧化作用后分别为5.7%和9.2%)。结论：银杏叶、山楂叶提取物对氧自由基具有强的抑制作用。     

近年银杏叶提取物研究进展

银杏叶提取物（ｇｉｎｋｇｏ ｂｉｌｏｂａ ｅｘｔｒａｃｔ,ＥＧｂ）是一种作用广泛、不良反应较少的天然药物。其有效成分主要为银杏黄酮和萜类,具有清除氧自由基、拮抗血小板活化因子（ＰＡＦ）、降血脂、增强中枢神经系统功能、调节神经递质和激素水平、改善血液流变学状态、抗炎、抗过敏等作用。本文对ＥＧｂ的化学成分和药理作用研究新进展作了综述。     

银杏叶提取物的胃粘膜保护作用

采用大鼠束缚－冷冻应激模型和小鼠无水乙醇损伤模型观察银杏叶提取物对胃摹员伤指数的影响;采用幽门结扎法收集胃液,观察ＧｂＥ对胃液分泌量,胃液酸度和胃蛋白酶活性的影响;采用硫代巴比妥酸法测定胃粘膜及血清中丙二醛的含量。结果表明,ＧｂＥ可剂量依赖性地抑制束缚－冷冻应激和无水乙醇引起的胃粘膜损伤。     

荞麦花叶提取物抗氧化活性与抑瘤作用的实验研究

目的:研究荞麦花叶提取物(extraction of buckwheat flower and leaf,EBFL)对肿瘤的抑制作用及其对荷瘤鼠体内抗氧化能力的影响。方法:建立S180小鼠实体瘤和腹水瘤模型,80只昆明种小鼠随机分为4组:模型组、EBFL 200,400 mg·kg-1剂量组ig给药、环磷酰胺(CTX,25 mg·kg-1)ip组。所有动物每日给药1次,连续给药20 d,测定EBFL给药后各处理组小鼠实体瘤重,腹水瘤小鼠体重和腹围增长速度,治疗组和对照组观察时间结点为25 d,计算各组平均生存率,以及全血谷胱甘肽过氧化物酶(GSH-Px)及血浆超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量。结果:EBFL处理15 d,荷瘤小鼠腹水增长、体重增长明显减慢,与模型组比较P<0.05。EBFL处理组腹水瘤小鼠生存率达25%。EBFL对肿瘤的生长有一定的抑制作用,但仍未达到CTX的水平。与对照组相比,EBFL(L,H)均可升高荷瘤小鼠血清中GSH-Px活性(P<0.05,P<0.01);EBFL(H)组小鼠血清SOD活性与对照组相比显著升高(P<0.05),作用效果与CTX相似;与对照组相比,EBFL(L,H)处理均可以显著降低小鼠血清MDA水平(P<0.05)。结论:荞麦花叶提取物对S180荷瘤小鼠有一定的抑制作用,能抑制荷瘤小鼠腹水生长,延长荷瘤小鼠生存率,这可能与提高实验小鼠体内的GSH-Px和SOD的活性,降低MDA含量有关。     

银杏叶提取物的毛细管电泳指纹图谱研究

目的 建立银杏叶提取韧的毛细管电泳指纹图谱。方法 EGb761为对照，芦丁为内参比物，采用毛细管电泳法分析银杏黄酮苷。结果 利用指纹图谱相似度计算软件，计算出各厂家样品与EGb761的相似度指数，建立银沓叶提取物的指纹图谱.结论 该研究有助于银杏叶提取物的质量控制。     

银杏叶提取物磷脂酰胆碱复合物对缺血大鼠学习记忆障碍的影响

 目的 观察银杏叶提取物磷脂酰胆碱复合物(Gb-PC)对血管性痴呆(VD)大鼠学习记忆功能的影响,并探讨其相关机制。方法 制备VD模型,采用避暗法及水迷宫法评价Gb-PC对VD模型大鼠学习记忆的影响,并测定大鼠海马组织中单胺氧化酶(MAO)及超氧化物歧化酶(SOD)活性,丙二醛(MDA)含量。结果Gb-PC可以明显改善VD大鼠的学习记忆功能,同时可不同程度抑制海马组织中MAO活性,增强SOD活性,减少MDA含量。结论 Gb-PC对VD大鼠学习记忆功能有一定的改善作用,其机制可能与提高脑组织中抗氧化酶活性,减轻生物膜脂质过氧化损伤以及抑制单胺氧化酶活性有关。     

Antimutagenic in vitro activity of plant polyphenols: Pycnogenol and Ginkgo biloba extract (EGb 761)

Ofloxacin (15 microg/mL) and acridine orange (5 microg/mL) induce mutagenicity by different mechanisms in the photosynthetic flagellate Euglena gracilis. The present study examined whether Pycnogenol (PYC; 5-100 microg/mL) or Ginkgo biloba extract (EGb 761; 5-100 microg/mL) could protect against the mutagenic effects of each of the mutagens and the potential mechanisms underlying such protection. The highest concentration of PYC and EGb 761 effectively reduced the mutagenic activity of both ofloxacin and acridine orange by more than 99% (p < 0.001). Using luminol-dependent photochemical methodology it was demonstrated that EGb 761 and PYC were effective antioxidants. In addition, as determined by spectrophotometry, PYC and EGb 761 bound acridine orange. Both PYC and EGb 761 have been shown to produce dual antimutagenic effects, as evidenced by both antioxidant and physicochemical properties. The findings suggest that EGb 761 and PYC would thus be suitable for future study, not only as antioxidants, but also as antimutagenic agents.     

The effects of Ginkgo biloba extract (LI 1370) supplementation and discontinuation on activities of daily living and mood in free living older volunteers

The aim of the study was to investigate the effects of continuing treatment with Ginkgo biloba extract (GBE) 120 mg/day on the activities of daily living (ADLs) and mood in healthy older volunteers who had immediately previously participated in a survey of the effects of a 4 month treatment with the drug.Following a prior postal survey investigating the effects of 4 months supplementation with GBE on ADLs and various aspects of mood and sleep, 1570 volunteers continued onto a 6 month follow-up postal survey. Subjects selected their own treatment option for the follow-up survey, which effectively created four groups: a continuation group who received GBE in the initial 4 month study and during the 6 month follow-up (GBE-GBE), a discontinuation group who received GBE in the initial study but not during the follow-up (GBE-NT), a new treatment group who did not receive GBE in the initial 4 month study but who did receive GBE during the 6 month follow-up (NT-GBE), and a no treatment group who received no treatment in either survey (NT-NT). At the end of the 6 month follow-up period each subject completed a line analogue rating scale (LARS) and a self-rating activities of daily living scale (SR-ADL).There were signi fi cant differences in the mean overall LARS and SR-ADL scores between the four treatment combination groups at the end of the follow-up period. A factor analysis of the LARS revealed two factors, 'mood' and 'alertness'. When scores from each of the treatment groups were examined over the whole 10 month period it was evident that the ratings of overall competence in the SR-ADL and both factors of the LARS were diminished on cessation of treatment with GBE, and improved when GBE treatment was initiated. The magnitude of the improvements on all scales was related to the overall duration of GBE supplementation.Signi fi cant differences between the groups of subjects treated with GBE for different periods of time (4-10 months) suggests that the extract has a demonstrable effect in improving mood and the self-assessed performance of the tasks of everyday living.     

银杏叶提取物在大鼠脑缺血再灌注损伤中的保护作用

目的：研究银杏叶提取物(GbE)对大鼠脑缺血再灌注损伤皮质内自由基、氨基酸动态平衡的影响及其对原代培养的大鼠海马神经元内游离钙离子浓度([Ca2+〕i)的影响和特征。方法：采用高压液相色谱仪测量大鼠大脑皮质中氨基酸(G1u、Asp,GABA、G1y)的浓度;MDA和GSH-Px采用TBA法测量,SOD采用嘌呤法测量。使用显微荧光检测系统检测单个原代培养的海马神经元内游离钙离子浓度([Ca2+)i)的变化和特征。结果：与非治疗组比较,GbE各浓度治疗组的缺血大脑皮质内G1u、Asp和MDA含量在各时间观察点(缺血3h、缺血再灌注lh和缺血再灌注2h)均明显降低(P＜0．0l或P＜0．05),而SOD和GSH-Px含量则在各时间观察点均明显升高(P＜0．0l或P＜0．05);GbE l0mg／kg、15mg／kg治疗组缺血大脑皮质内的GAGB和G1y含量在各时间观察点均有所降低(P＜0．05)。与GbE 5mg/kg治疗组比较,GbE l0mg/kg,15mg／kg治疗组大脑皮质内的G1u、Asp和MDA含量在各时间观察点较低(P＜0．05),而GABA,Gly,SOD和GSH=Px含量则较高(P＜0．05);GbE l0mg/kg治疗组与15mg／kg治疗组之间差异无显著性。当向原代培养的神经元同时给予谷氨酸l×l0—5mol／L和GbE 25μg／m120s时所诱导的[Ca2+]i明显低于单独使用谷氨酸l×l0—5mol／L所诱导的[Ca2+]i变化,其峰值明显下降,且在上升阶段其升高速度减慢,下降阶段的时间也有所缩短,二者之间的平台期相对延长,当其返回基线后,再次给予谷氨酸l×l0-5mol／L时,其反应可恢复。结论：GbE在大鼠脑再灌注损伤中可通过保持抑制性氨基酸／兴奋性氨基酸、自由基系统的平衡,及快速抑制谷氨酸诱导大鼠海马神经元内[Ca2+]i浓度升高,从而保护受损的神经元。     

Ginkgo biloba extract prevents glucose‐induced accumulation of ECM in rat mesangial cells

Pathological remodeling characterized by extracellular matrix (ECM) accumulation contributes to diabetic nephropathy (DN). This study evaluated the effects of Ginkgo biloba extract (GbE) on the metabolism of the ECM in rat mesangial cells cultured in hyperglycemic conditions. The cultured mesangial cells in high glucose conditions were allotted into six groups: normal control group, high glucose group, low concentration of GbE group, moderate concentration of GbE group, high concentration of GbE group, and captopril group. In the presence of high glucose, the levels of matrix metalloproteinase‐2 (MMP‐2), matrix metalloproteinase‐9 (MMP‐9) and extracellular matrix metalloproteinase inducer (EMMPRIN) were decreased significantly, and the levels of tissue inhibitor of metalloproteinase‐2 (TIMP‐2), tissue inhibitor of metalloproteinase‐1 (TIMP‐1) and plasminogen activator inhibitor‐1 (PAI‐1) were increased significantly. These changes were reversed by GbE. GbE lowered the levels of transforming growth factor‐β₁ (TGF‐β₁), insulin‐like growth factor‐1 (IGF‐1) and connective tissue growth factor (CTGF) of the high glucose group. Furthermore, GbE also decreased the expressions of collagen IV and laminin of the high glucose group. In summary, the results suggest that GbE postpones the extracellular matrix accumulation by inhibiting the synthesis of ECM and promoting the degradation of ECM, and therefore, is a potential drug for the prevention and treatment of DN. Copyright © 2008 John Wiley & Sons, Ltd.     

The antioxidant activity of standardized extract of Ginkgo biloba (EGb 761) in rats

The standardized extract of Ginkgo biloba (EGb 761) has been widely employed for its significant benefit in neurodegenerative disorders. Although antioxidative actions have been attributed to this extract, the mechanisms of the multiple principles involved in this pharmacological activity are not completely established. Parkinson's and Alzheimer's diseases are frequently associated with oxidative stress and defects in the cellular protective mechanisms. In this study, the lipid peroxidation (LPO) and the activity of the antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD) were evaluated in the hippocampus, striatum and substantia nigra (SN) of rats treated with EGb 761. An increase in the CAT and SOD activities in the hippocampus, striatum and SN, and a decrease of the LPO in the hippocampus were observed. These data are additional to the antioxidant properties of EGb 761 reported in the literature and indicate a possible role for the extract in the treatment of diseases involving free radicals and oxidative damage.     

银杏叶提取物改善L-甲状腺素诱导的大鼠心肌缺血/再灌注损伤

目的 研究银杏叶提取物对L-甲状腺素诱导的心肌肥厚合并缺血/灌注引起的心律失常的保护作用.方法 SD大鼠分为5个组,分别为正常组,模型组,倍他乐克(10mg/kg·d-1)组,银杏叶提取物高、低(100、50 mg/kg·d-1)剂量组,按0.4 mg/g·d-1皮下注射L-甲状腺素10d造模,同时灌胃给药治疗.在第1...     

银杏叶提取物注射液联合神经节苷脂治疗缺血性脑血管病的疗效观察研究

目的:观察银杏叶提取物注射液联合神经节苷脂治疗缺血性脑血管病的临床疗效。方法:根据患者的情况选择治疗方法,对不能溶栓的患者采取抗凝治疗,其他患者3 h内均采用溶栓治疗,在此基础上,A组患者中采用神经节苷脂静脉滴注,B组患者则在A组的基础上联合银杏叶提取物注射液,对比两组患者的总临床疗效率、血流动力学指标、治疗后的总不良反应率以及治疗前后的美国国立卫生院卒中量表(National Institutes of Health Stroke Scale,NIHSS)评分。结果:B组患者总临床疗效率高于A组,B组患者的全血低切粘度、全血高切粘度、纤维蛋白原、红细胞比容均低于A组,B组患者的总不良反应率低于A组,B组患者的NIHSS评分在降低幅度上明显优于A组,差异符合统计学意义(P<0.05)。结论:银杏叶提取物注射液联合神经节苷脂治疗缺血性脑血管病临床疗效更佳,能有效改善患者的脑循环,促进神经血管的恢复情况,应用前景广阔。