应用圆二色谱法验证银杏内酯的绝对构型及银杏提取物的化学成分

目的验证银杏内酯A、B的绝对构型,并对银杏提取物的化学成分进行研究。方法应用圆二色谱法并依据Klyne内酯八区-扇形区律对银杏内酯A、B的绝对构型进行分析讨论;采用反复硅胶柱色谱、聚酰胺柱色谱、Sephadex LH-20柱色谱、高效液相色谱、重结晶等方法分离化学成分,1H-NMR1、3C-NMR等方法进行结构鉴定。结果从银杏提取物中分离得到11个化合物,分别鉴定为:芫花素(genkwanin,1)、异鼠李素(isorhamnetin,2)、山奈酚(kaempferol,3)、槲皮素(quercetin,4)、白果内酯(bilobalide,5)、银杏内酯A(ginkgolide A,6)、银杏内酯B(ginkgolide B,7)、银杏内酯C(ginkgolide C,8)、芦丁(rutin,9)、β-谷甾醇(-βsitosterol,10)、胡萝卜苷(daucosterol,11)。结论银杏内酯A、B的绝对构型与文献报道相符。     

高速逆流色谱法分离纯化银杏叶中白果内酯和银杏内酯A、B、C

目的从银杏叶中分离纯化白果内酯和银杏内酯A、B、C。方法银杏叶提取液经醋酸乙酯萃取、D-101大孔吸附树脂柱和Al2O3柱纯化后得到总内酯提取物,提取物再经两次高速逆流色谱分离制备4种内酯单体。结果25%乙醇热提取、醋酸乙酯萃取、D-101柱、pH4.0的Al2O3柱对总内酯的提纯最终使总内酯质量分数达到44.98%。经高速逆流色谱制备得到的白果内酯和银杏内酯A、B、C最高质量分数分别为98.3%、98.9%、98.8%、98.4%。结论本法简便快速、回收率高,为银杏叶中内酯单体的制备提供了一种新方法     

银杏萜内酯类注射液治疗缺血性脑卒中疗效及安全性的系统评价

目的 系统性评价银杏萜内酯类注射液治疗缺血性脑卒中的疗效及安全性。方法 检索中国期刊全文数据库（CNKI）、维普中文科技期刊全文数据库（VIP）、中国生物医学文献数据库（CBM）、万方数据库、EMBASE、Pubmed和The Cochrane Library,检索截止日期为2017年12月。纳入银杏萜内酯类注射液治疗缺血性脑卒中的随机对照试验研究,采用RevMan5.2软件对临床疗效及神经功能缺损评分进行Meta-分析。结果 最终纳入临床研究13项,涉及患者1 330例。Meta-分析结果显示,银杏内酯注射液治疗缺血性脑卒中患者的临床疗效优于对照组[RR=1.14,95%CI（1.03,1.25）,Z=2.59,P=0.009];银杏内酯B注射液治疗缺血性脑卒中患者的临床疗效与对照组相当[RR=1.13,95%CI（0.95,1.33）,Z=1.36,P=0.17];银杏二萜内酯葡胺注射液治疗缺血性脑卒中患者的临床疗效优于对照组[RR=1.17,95%CI（1.08,1.27）,Z=3.69,P=0.0002];银杏内酯注射液改善缺血性脑卒中患者的神经功能缺损评分与对照组相当[MD=-0.43,95%CI（-4.32,3.46）,Z=0.22,P=0.83];银杏内酯B注射液改善缺血性脑卒中患者的神经功能缺损评分与对照组相当[[MD=-0.87,95%CI（-2.64,0.91）,Z=0.96,P=0.34];银杏二萜内酯葡胺注射液改善缺血性脑卒中患者的神经功能缺损评分优于对照组[MD=-1.62,95%CI（-2.63,-0.60）,Z=3.13,P=0.002];纳入研究均未报道银杏萜内酯类注射液引起严重不良反应。结论 银杏萜内酯类注射液治疗缺血性脑卒中患者可提高临床疗效、减少神经功能缺损,但缺乏临床意义证据。尚需更多高质量研究以增加证据的强度。     

Pharmacokinetics of bilobalide,ginkgolide A and B after administration of three different Ginkgo biloba L. preparations in humans

A sensitive LC‐ESI‐MS method with a solid‐phase extraction was established for the determination of bilobalide, ginkgolide A and ginkgolide B in human plasma; bioavailability and pharmacokinetics of three different Ginkgo biloba L. preparations have been investigated. The preparations used in the present single‐dose pharmacokinetic study were different formulations of Ginkgo biloba L. extracts (Geriaforce? tincture, new Ginkgo fresh plant extract tablets and EGb 761?) with various excipients. The analysis of Ginkgo terpene lactones was performed by LC‐MS on a Zorbax^® SB‐C18 column. The mobile phase consisted of water + 0.1% acetic acid and methanol 68/32 (v/v) to 49/51 (v/v) at a flow rate of 200 μL/min. Bilobalide, ginkgolide A and ginkgolide B were monitored using the selected‐ion monitoring (SIM) mode at m/z of 325, 453 and 423, respectively. The amounts of the active compounds (terpene lactones) in the administered products were in the low‐mg range per dose. The assay method was successfully applied to the study of the pharmacokinetics and bioavailability of bilobalide, gingkolide A and ginkgolide B in humans. The resulting maximum concentrations (median) of bilobalide, ginkgolide A and ginkgolide B in plasma after administration of the maximum daily dose of the different Ginkgo products were 3.53, 3.62, and 1.38 ng/mL respectively after administration of Geriaforce? tincture; 11.68, 7.36, and 4.18 ng/mL, respectively after taking Ginkgo fresh plant extract tablets; and 26.85, 16.44, 9.99 ng/mL, respectively after administration of EGb 761? tablets. These data are relevant to demonstrate relative bioavailabilities of different Ginkgo biloba L. preparations (Geriaforce? tincture, new Ginkgo fresh plant extract tablets and EGb 761?). Copyright © 2009 John Wiley & Sons, Ltd.     

白果内酯治疗实验大鼠肺孢子虫肺炎电镜观察

目的　观察白果内酯对卡氏肺孢子虫超微结构的影响。方法　地塞米松连续皮下注射Wistar大鼠 6周 ,建立大鼠卡氏肺孢子虫肺炎动物模型 ,腹腔内注射白果内酯 30mg/(kg·d)× 8d。停药 1周后取大鼠肺组织作超薄切片 ,透射电镜观察。结果　白果内酯作用后的卡氏肺孢子虫虫体有大量空泡形成 ,细胞器肿胀破坏 ,髓样结构形成 ,胞膜破坏 ,胞质内出现电子密度较高颗粒。结论　白果内酯可破坏卡氏肺孢子虫的超微结构 ,从而引起虫体死亡。     

The effects of Ginkgo biloba on metabolic syndrome: A review

The Ginkgo biloba (G. biloba), commonly known as ginkgo, brings considerable benefit to common medicine, including weight loss effects, as well as antidiabetic, antihypertensive, and antilipidemic properties that could be effective in the treatment of Metabolic syndrome (MetS ) associated with increased risk of cardiovascular disease events. Major compounds of G. biloba are terpene lactones (bilobalide and ginkgolides A, B, and C) and flavone glycosides (isorhamnetin, quercetin, and kaempferol). We evaluated the most relevant original articles to indicate the effects of G. biloba on different components of MetS, including obesity, high blood pressure, dyslipidemia, and hyperglycemia. Several electronic databases (Scopus, PubMed, Web of Science and Google Scholar) were searched and the articles that included Ginkgo's effect on one or more of the criteria for MetS were selected. This review indicated that G. biloba might be efficient in the improvement of MetS; however, more studies especially clinical trials are needed to evaluate safety and efficacy of G. biloba.     

Effects of Ginkgo biloba extract (EGb 761) on gene expression: Possible relevance to neurological disorders and age‐associated cognitive impairment

Ginkgo biloba leaf extract (EGb 761), which contains many constituents, including flavonoid glycosides and terpenoids (ginkgolides, bilobalide), is used to treat cerebrovascular and peripheral vascular insufficiency, as well as cognitive impairment and other symptoms of dementia. Recent studies have indicated that these therapeutic effects of EGb 761 probably involve modification of the expression of many genes by actions involving several of its active constituents. As examples: EGb 761 and its ginkgolide B constituent inhibit the expression of the peripheral benzodiazepine receptor in the adrenal cortex and decrease circulating levels of corticosterone in the rat, effects that provide a mechanism for explaining the “antistress” action of the extract. Both the flavonoid and terpenoid constituents of EGb 761 decrease the expression of inducible nitric oxide synthase (iNOS), supporting an action of the extract of opposing the deleterious effects of excessive formation of NO. EGb 761 upregulates several genes that encode vital antioxidant enzymes, including heme oxygenase‐1 and the regulatory and catalytic subunits of γ‐glutamyl‐cysteinyl synthetase. Dietary treatment of mice with EGb 761 upregulates the expression of genes encoding neuronal tyrosine/threonine phosphatase 1 and microtubule‐associated tau in the cerebral cortex, findings that are of interest since these proteins are associated with the intracellular neurofibrillary tangles found in the brain in Alzheimer's disease. Bilobalide upregulates two mitochondrial‐DNA‐encoded genes, subunit III of cytochrome c oxidase and subunit ND1 of NADH dehydrogenase, indicating a fundamental mechanism that may underlie EGb 761‐induced neuroprotection. Collectively, such results indicate that the therapeutic effects of EGb 761 on cognitive impairment (dementia) may involve its action of altering gene expression. Drug Dev. Res. 57:214–235, 2002. 2003 Wiley‐Liss, Inc.     

银杏内酯注射液及其组分对大鼠缺血性脑卒中模型作用比较及对突触后致密物95表达的影响

目的 研究银杏内酯注射液（GIs）及其主要组分银杏内酯B（GB）和白果内酯（BB）对急性缺血性脑损伤的改善作用,以及GIs对突触后致密物95（PSD95）蛋白表达的影响。方法 ①采用Longa法制备大鼠大脑中动脉阻塞（tMCAO）模型,于缺血再灌注1 h后给予GIs（2.5、5.0 mg/kg）、GB（1.25、2.50 mg/kg）、BB（1.25、2.50 mg/kg）,每天给药2次,连续给药3 d。于术后24、48、72 h各进行神经功能评分1次;TTC染色法测定脑梗死体积;称大鼠干湿质量,测定脑组织含水量。②大鼠随机分为假手术组、GIs单给药（2.5 mg/kg）组、模型组和GIs治疗（tMCAO+GIs 2.5 mg/kg）组,制备tMCAO模型,再灌1 h后开始ip给药,3 d内每天给药2次。分别于再灌注后24、72 h取脑,Western blotting法检测缺血半影区PSD 95蛋白表达水平。结果 ①与模型组比较,GIs及其主要组分GB、BB均显著改善tMCAO模型大鼠神经运动功能障碍,减少脑梗死体积,降低脑水肿（P<0.05、0.01）;同等剂量下（2.5 mg/kg）,GIs治疗效应优于单组份GB、BB。②GIs组给药后胞浆PSD95蛋白水平均较模型组显著升高（P<0.05、0.01）。结论 GIs及其有效组分GB、BB均具有改善tMCAO大鼠急性缺血性损伤的作用,GIs的作用优于GB、BB单独用药,作用机制可能与上调PSD95蛋白表达相关。     

HPLC法测定银杏叶粉针中总黄酮醇苷和萜类内酯

目的采用高效液相色谱法测定银杏叶粉针中总黄酮醇苷和总萜类内酯。方法黄酮醇苷水解后,采用HPLC-UV法测定;萜类内酯用醋酸乙酯萃取后采用HPLC-ELSD法测定。结果槲皮素、山柰素、异鼠李素分别在5.104～51.04、5.000～50.00、1.38～13.8μg/mL呈良好线性关系,平均回收率分别为99.34%、99.25%、101.2%(n=5);银杏内酯A、B、C及白果内酯分别在0.415～2.075、0.402～2.010、0.426～2.130、0.803～4.015mg/mL呈良好线性关系,平均回收率分别为99.28%、100.1%、101.0%、99.31%(n=5)。结论本实验采用的方法简便快速,结果准确,重现性好,可用于银杏叶粉针中黄酮和内酯类成分的质量控制。     

白果内酯在PC12细胞中对NO诱导的细胞毒性的保护作用(英文)

目的:研究白果内酯在PC12细胞中对NO诱导的细胞毒性的保护作用。方法:以MTT法及LDH法检测细胞存活率;同时检测细胞的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性及脂质过氧化水平。结果:NO供体SIN-1(50-300μmol·L~(-1))可导致PC12细胞死亡,可使PC12细胞脂质过氧化水平升高。白果内酯预孵育可减少NO诱导的细胞死亡;可抑制脂质过氧化水平升高。白果内酯预孵育本身可使SOD及CAT酶活性升高。结论:白果内酯对NO诱导的细胞毒性作用具保护作用,该保护作用可能与白果内酯升高细胞内SOD和CAT的活性有关。