大鼠肠内菌转化连翘苷的代谢产物

应用液相色谱-串联质谱法研究肠内菌转化连翘苷的代谢产物.将连翘苷与大鼠肠内菌于体外厌氧温孵培养,在温孵液中检测到连翘苷及其3种代谢产物.放大制备了转化产率高的代谢物,依据1H NMR和ESI-MS数据推测代谢物结构并假设了连翘苷可能的代谢途径.     

抗焦虑新药AF-5及其代谢物在人肝微粒体体外温孵体系中代谢研究

目的研究一类抗焦虑新药AF-5及其代谢物(I,II)在人肝微粒体体外温孵体系中代谢情况.方法自制人肝微粒体,用Lowry法测定酶活性为8.79mg·mL^-1.以此配制人肝微粒体体外温孵体系,加入药物,温孵后,提取分离,GC-MS测定.结果鉴定了AF-5在人肝微粒体体外温孵体系中的两个主要代谢物,并阐明了其体外代谢途径为AF-5的4位首先氧化为羟基,然后氧化成羰基.结论AF-5在体外人肝微粒体温孵体系中,100min后完全代谢成羟基代谢物I及羰基代谢物II,以羟基代谢物为主要代谢产物.AF-5代谢物I在人肝微粒体温孵体系中,可转化为代谢物II,而代谢物II在人肝中则不再代谢.     

左旋黄皮酰胺在大鼠肝微粒体中的代谢转化研究

用大鼠肝微粒体体外温孵法进行了左旋黄皮酰胺[(-)-clausenamide]代谢转化研究,优化了温孵体系,建立了反相HPLC-DAD同时分离检测左旋黄皮酰胺及其体外代谢产物的分析方法。用硅胶低压柱色谱、制备TLC及制备HPLC分离纯化了两个代谢产物并进行了光谱鉴定。结果表明,两个代谢物分别确定为6-和5-位羟基取代的黄皮酰胺。     

大鼠和人肠道菌群对苯环喹溴铵代谢转化作用的研究

目的:研究大鼠和人肠道菌群对苯环喹溴铵(BCQB)代谢的影响。方法:采用体外肠道菌群代谢方法,将大鼠或人的粪便溶解于人工肠液中,搅拌混合后过滤,滤液加入1mg·mL-1的苯环喹溴铵溶液0.5mL,于37℃厌氧培养48h,采用高效液相色谱串联质谱法对大鼠或人肠内菌温孵液样品进行分离和定性分析,并设不加BCQB溶液的大鼠或人肠内菌温孵液为空白样品。结果:与空白样品比较,大鼠或人肠内菌温孵液样品中总离子流色谱中除BCQB峰外未见新增色谱峰,其质谱碎片信息显示只有BCQB的特征碎片离子,未检测到BCQB的代谢产物。结论:在离体条件下,BCQB不被大鼠和人的肠道菌群代谢。     

尼索地平光解动力学和pH值对稳定性影响的研究

目的：考察尼索地平光解动力学和pH值对稳定性的影响。方法：采用HPLC法测定尼索地平浓度、并考察不同浓度尼索地平光解动力学及不同pH条件下尼索地平甲醇溶液的稳定性。结果：经指数衰减非线性回归分析，低浓度尼索地平甲醇溶液的光解反应级数n=1；尼索地平在pH3．2—7．9下避光放置，未见光解产物。结论：尼索地平甲醇溶液光降解属一级动力学过程；尼索地平在pH3．2-7．9间稳定。     

间尼索地平对兔实验性动脉粥样硬化的影响

<正> 在动脉粥样硬化(AS)的发生发展中,钙几乎参与了每个环节,细胞内钙超载能诱发和加速病变的形成.新二氢吡啶类钙拮抗剂尼索地平能减轻动脉粥样硬化斑块,间尼索地平与尼索地平的药理作用基本相同.本实验观察了间尼索地平对兔实验性动脉粥样硬化的作用,并与尼索地平进行比较.     

新型钙通道拮抗剂间-尼索地平及尼索地平

<正> 尼索地平(nisoldipine)是近年西德研制的新型二氢吡啶钙通道拮抗剂。具有强效、长效、速效心血管扩张作用。对防治冠心病、高血压病、及慢性充血性心力衰竭有显著疗效,能减少因急性心肌梗塞后导致的致命性心室颤动的危险性。但其见光易分解,故本文作者等人于1985年改造其化学结构,首创间-尼索地平(m-nisoldipine)并经UV、IR、NMR、及MS四谱确证其化学结构。间-尼索地平具有与尼索地平相似的药理作用,有七项药理作用优于尼索地平(详见本文3.2段的内容)。现概述如下。     

人参皂苷Rg1的肠内菌代谢及其代谢产物吸收入血的研究

目的 :研究人参皂苷Rg1(Rg1)在人及大鼠体内经肠内菌代谢后的变化及吸收入血代谢物的确定。方法 :生物样品 (血、尿、粪便 )经处理后分别做TLC ,ESI MS及HPLC检测分析。结果 :在大鼠尿和血中有代谢物Rh1/F1存在 ;在人的尿中有Rh1存在。结论 :在大鼠和人的血内 ,Rg1主要以其代谢产物形式存在。     

氯代正丁苯酞在大鼠肝微粒体中的代谢研究

用大鼠肝微粒体体外温孵方法进行了氯代正丁苯酞(CBP)代谢转化研究,优化了温孵体系的组成,建立了反相HPLC-DAD在线同时分离检测CBP及其4个体外代谢产物的分析方法,并比较了在苯巴比妥(PB)与3-甲基胆蒽(3-MC)诱导的微粒体中代谢差别。利用TLC、柱色谱与制备HPLC分离纯化了3个主要代谢产物,并进行了NMR,MS,UV等光谱鉴定,确定了其主要代谢产物为γ-羟基氯代正丁苯酞与β-羟基氯代正丁苯酞及它们的立体异构体。     

柚皮苷的人肠内菌生物转化(英文)

柚皮苷(1)是酸橙中含量最高的二氢黄酮苷类化合物, 将其与人肠内菌丛共温孵, 从温孵物中通过色谱方法得到原形化合物1和四个转化产物 (2-5), 根据谱学数据确定它们分别为柚皮苷-6"-乙酰物(2)、柚皮素(3)、根皮酸(4)和间苯三酚(5)。在1的糖苷链葡萄糖基6位能够特异性地发生乙酰化作用。1口服难以吸收。本文结果为阐明其生物利用度低提供了实验依据, 推测表现其生物活性的物质基础主要是其肠内菌生物转化产物3。肠内菌丛所致1的生物转化的继发结果,是它的转化产物吸收进入体循环发挥生物学作用, 此结果为进一步或再评价其体内过程、作用或毒性及其生物利用度提供了有用的信息。     

刺五加苷B、苷E在体外大鼠肠道菌群中的代谢

目的：观察体外大鼠肠道菌群对刺五加苷B、苷E的代谢。方法：收集大鼠新鲜粪便在厌氧培养基37℃培养24h,分别加入刺五加苷B、刺五加苷E,培养后加甲醇提取离心,取上清液采用HPLC及UPLC/MS方法对代谢成分进行分离和定性分析。结果：刺五加苷B、苷E在大鼠粪便孵育液中代谢,24h后样本中能检测出较高浓度代谢物。在离体条件下,刺五加苷B、苷E可以被大鼠的肠道菌群代谢,经过UPLC/MS的检测,刺五加苷B代谢物的分子离子峰[M＋H]~＋为193.08,推测为刺五加苷B的苷元再脱一分子水;刺五加苷E代谢物的分子离子峰[M＋H]~＋为417.17,推测为刺五加苷B的苷元。结论：刺五加苷B、苷E可以被大鼠肠道菌群代谢。     

Characterization of metabolites of worenine in rat biological samples using liquid chromatography–tandem mass spectrometry

The in vivo and in vitro metabolites of worenine in rat were identified or characterized using a specific and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. In vivo samples including rat urine, feces, and plasma samples were collected after ingestion of 25 mg/kg worenine to healthy rats. The in vivo and in vitro samples were cleaned up by a solid-phase extraction procedure (C18 cartridges) and a liquid–liquid extraction procedure, respectively. Then these pretreated samples were injected into a reversed-phase C18 column with mobile phase of methanol–ammonium acetate (2 mM, adjusted to pH 3.5 with formic acid) (60:40, v/v) and detected by an on-line MS/MS system. As a result, at least twenty-seven metabolites and the parent medicine were found in rat urine after ingestion of worenine. Seven metabolites and the parent medicine were identified or characterized in rat feces. Three metabolites and the parent medicine were detected in rat plasma. One metabolite was found in the rat intestinal flora incubation mixture, and three metabolites were characterized in the homogenized liver incubation mixture. The main phase I metabolism of worenine in rat was dehydrogenization, hydrogenation, hydroxylation, and demethylene reactions, and that of phase II was sulfation and glucuronidation.     

Screening for metabolites of acarviostatin family aminooligosaccharides in rats using ultraperformance liquid chromatography coupled with electrospray ionization tandem mass spectrometry

An ultraperformance liquid chromatography coupled with electrospray ionization tandem mass spectrometry (UPLC/ESI–MS/MS) procedure was used to identify trace levels of metabolites after the administration of acarviostatin II03 or III03 to rats. Biosamples of the feces and urine of the treated rats as well as the intestinal sacs incubated with the drugs in vitro were pre-treated by cation-exchange extraction, and then applied to a reversed-phase C₁₈ UPLC column with acetonitrile/1.5 mM aqueous ammonia as the mobile solvent. The parent drug and the potential metabolites were identified by two independent qualitative parameters, retention time (t_R) and MS/MS spectrum. Seven metabolites were successfully characterized from the intestinal sacs infused with acarviostatin II03 or III03. The metabolic pathways within the intestine were identified including glucose hydrolysis at the reducing terminus, and cyclohexitol hydrolysis at the non-reducing terminus of the parent acarviostatins. Subsequently, we determined that lower amounts of cyclohexitol-lost metabolites compared with the cyclohexitol-containing metabolites, as well as lower amounts of the acarviostatin III03 metabolites compared with the acarviostatin II03 metabolites, could be transferred by the intestinal walls. In the rat feces samples, although the parent compounds could not be found, acarviostatin II03 and III03 both yielded one-glucose-lost and four-glucose-lost types of metabolites. In the rat urine samples, no acarviostatin metabolites could be detected.     

Identification of metabolites of tectoridin in-vivo and in-vitro by liquid chromatography-tandem mass spectrometry

In this work, liquid chromatography-electrospray ionization tandem ion-trap mass spectrometry (LC-MS(n)) was used to investigate the in-vivo and in-vitro metabolism of tectoridin. After oral administration of a single dose (100 mg kg(-1)) of tectoridin to healthy rats, faeces and urine samples were collected for 0-48 h and 0-24 h, respectively. Tectoridin was also incubated with rat intestinal flora and rat liver microsomes. Samples from in-vivo and in-vitro metabolism studies were purified using a C(18) solid-phase extraction cartridge, then separated using a reverse-phase C(18) column with methanol/ water (30:70, v/v, adjusted to pH 10.0 with ammonia water) as mobile phase and detected by an on-line MS(n) system. The structure of the metabolites was elucidated by comparing their molecular weights, retention times and full-scan MS(n) spectra with those of the parent drug. The results revealed six metabolites of tectoridin in urine (tectorigenin, hydrogenated tectorigenin, mono-hydroxylated tectorigenin, di-hydroxylated tectorigenin, glucuronide-conjugated tectorigenin and sulfate-conjugated tectorigenin); three metabolites in faeces (tectorigenin, di-hydroxylated tectorigenin and sulfateconjugated tectorigenin); one metabolite in the intestinal flora incubation mixture (tectorigenin), and four in the liver microsomal incubation mixture (tectorigenin, hydrogenated tectorigenin, mono-hydroxylated tectorigenin and di-hydroxylated tectorigenin). Except for tectorigenin, all other metabolites of tectoridin are reported for the first time.     

Structural elucidation of in vivo and in vitro metabolites of anisodine by liquid chromatography-tandem mass spectrometry

Liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESIMSn) was employed to investigate the in vivo and in vitro metabolism of anisodine. Feces, urine and plasma samples were collected after ingestion of 20 mg anisodine to healthy rats. Feces and urine samples were cleaned up by liquid-liquid extraction and solid-phase extraction procedures (C18 cartridges), respectively. Methanol was added to plasma samples to precipitate plasma proteins. Anisodine was incubated with homogenized liver and intestinal flora of rats in vitro, respectively, followed by extraction with ethyl acetate. LC-MSn was used for the separation and identification of the metabolites using C18 column with mobile phase of methanol/0.01% triethylamine solution (2 mM, adjusted to pH 3.5 with formic acid) (60:40, v/v). The results revealed that five metabolites (norscopine, scopine, alpha-hydroxytropic acid, noranisodine and hydroxyanisodine) and the parent drug existed in feces. Three new metabolites (dimethoxyanisodine, tetrahydroxyanisodine and trihydroxy-methoxyanisodine) were identified in urine. Four metabolites (norscopine, scopine, hydroxyanisodine and anisodine N-oxide) and the parent drug were detected in plasma. Two hydrolyzed metabolites (scopine and alpha-hydroxytropic acid) were found in rat intestinal flora incubation mixture, and two metabolites (aponoranisodine and anisodine N-oxide) were identified in homogenized liver incubation mixture.     

Mass spectrometric and NMR characterization of metabolites of roxifiban, a potent and selective antagonist of the platelet glycoprotein IIb/IIIa receptor

1. The methyl ester prodrug roxifiban is an orally active, potent and selective antagonist of the platelet glycoprotein GPIIb/IIIa receptor and is being developed for the prevention and treatment of arterial thrombosis. 2. Roxifiban was rapidly hydrolyzed to the zwitterion XV459 in vivo and by liver slices from the rat, mouse and human and by intestinal cores from dog. XV459 was metabolized to only a small extent in vitro and in vivo. 3. Studies with rat and dog given radiolabelled roxifiban showed limited oral absorption with the majority of the radiolabel being excreted in faeces. After i.v. doses of 14C-roxifiban, most of the radioactivity was recovered in the urine of rat whereas the dog excreted significant amounts of radioactivity in bile and urine. 4. XV459 could be metabolized extrahepatically by dog gut flora to produce an isoxazoline ring-opened metabolite. In vitro hepatic metabolism of XV459 was mainly by hydroxylation at the prochiral and chiral centres of the isoxazoline ring. These hydroxylated metabolites were not detected in the urine and plasma of human volunteers administered roxifiban. 5. Initial LC/MS identification of metabolites was achieved by dosing the rat with an equimolar mixture of d0:d4 roxifiban and detecting isotopic clusters of pseudomolecular ions. Unequivocal characterization of these metabolites was achieved by LC/MS, LC/NMR and high-field NMR techniques using synthetic standards of the metabolites. 6. The synthesis of one hydroxylated metabolite enabled the assignment of the correct stereochemistry of the substituted hydroxyl group on the isoxazoline ring.     

基于肠心轴学说探讨肠道菌群在心血管疾病中的作用

肠道内庞大的菌群之间相互依存、相互制约,协同参与机体生理代谢和营养物质的消化。肠道菌群与心血管健康相关研究已成为十分重要的研究领域,肠道菌群组成的改变、肠道菌群产生的代谢产物和毒素都能引发心血管系统的病变。心血管疾病(cardiovascular disease,CVD)因高发病率和死亡率已成为一个主要的健康问题,CVD的发生、发展中肠道特定菌群的改变已被确定为疾病发生的关键因素。然而,肠道菌群及其代谢产物如何产生及影响CVD的潜在机制仍不清楚。本文就肠道菌群通过肠心轴调节CVD的最新研究进展进行综述,重点总结肠道微生物及其代谢产物与CVD发生发展之间复杂的相互作用,以及肠道菌群失调的改变对心血管事件发生的影响,探讨肠道菌群与CVD发病机制之间的因果联系。     

Identification of in‐vivo and in‐vitro metabolites of palmatine by liquid chromatography–tandem mass spectrometry

Objectives Despite its important therapeutic value, the metabolism of palmatine is not yet clear. Our objective was to investigate its in‐vivo and in‐vitro metabolism. Methods Liquid chromatography–tandem electrospray ionization mass spectrometry (LC‐ESI/MSⁿ) was employed in this work. In‐vivo samples, including faeces, urine and plasma of rats, were collected after oral administration of palmatine (20 mg/kg) to rats. In‐vitro samples were prepared by incubating palmatine with intestinal flora and liver microsome of rats, respectively. All the samples were purified via a C₁₈ solid‐phase extraction procedure, then chromatographically separated by a reverse‐phase C₁₈ column with methanol–formic acid aqueous solution (pH 3.5, 70: 30 v/v) as mobile phase, and detected by an on‐line MSⁿ detector. The structure of each metabolite was elucidated by comparing its molecular weight, retention time and full‐scan MSⁿ spectra with those of the parent drug. Key findings The results revealed that 12 metabolites were present in rat faeces, 13 metabolites in rat urine, 7 metabolites in rat plasma, 10 metabolites in rat intestinal flora and 9 metabolites in rat liver microsomes. Except for six of the metabolites in rat urine, the other in‐vivo and in‐vitro metabolites were reported for the first time. Conclusions Seven new metabolites of palmatine (tri‐hydroxyl palmatine, di‐demethoxyl palmatine, tri‐demethyl palmatine, mono‐demethoxyl dehydrogen palmatine, di‐demethoxyl dehydrogen palmatine, mono‐demethyl dehydrogen palmatine, tri‐demethyl dehydrogen palmatine) were reported in this work.     

R,S-1-(2-甲氧基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪在大鼠血浆中代谢产物的研究

目的研究R,S-1-(2-甲氧基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪(naftopidil，NAF)在大鼠血浆中的代谢产物。方法用LC/MS法对大鼠口服NAF后的血浆样品进行分析，根据检测到的代谢产物与原形药的质谱行为及类似结构化合物的代谢规律，推测可能的代谢产物。合成对照品，通过比较代谢产物和合成对照品的色谱和质谱行为，对I相代谢物予以确认。通过质谱信息及酶水解的方法间接鉴定II相代谢物。结果大鼠血浆中发现I相代谢物：R,S-1-(2-羟基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪(DMN)、R,S-1-(2-甲氧基-4-羟基苯基)-4-［3-(萘-1-氧基)-2-羟基丙基］哌嗪(PHN)，R,S-1-(2-甲氧基苯基)-4-［3-(4-羟基萘-1-氧基)-2-羟基丙基］哌嗪(NHN)及II相代谢物：NAF和NHN与<>-D-葡糖醛酸形成的结合物。结论NAF在大鼠血浆中的主要代谢途径是苯环、萘环羟基化和苯环邻位甲氧基的脱甲基化。此外，萘羟化代谢物和原形药与内源性分子<>-D-葡糖醛酸形成结合物也是原形药的代谢方式之一。