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11.
《中医科学杂志(英文)》2020,7(3):233-244
ObjectiveThe objective of this study was to verify the lipid-lowering effect of Juhe Fang extract (JHFE) and to determine its characteristic chemical profile in vitro and in vivo.MethodsA hyperlipidemia model was established by feeding mice a high-fat diet (HFD). After treatment for 30 days, serum total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels were measured with an automatic biochemistry analyzer. The components from JHFE obtained from in vivo and in vitro experiments were investigated using an UPLC-Q Exactive-Orbitrap MS/MS.ResultsThe TC, TG, and LDL-C in the serum significantly decreased and the HDL-C significantly increased after JHFE treatment. A total of 95 compounds from JHEF including 15 phenolic acids (PA), 4 phenylethanoid glycosides (PG), 24 flavonoids (F), 14 triterpenoids (T), 10 diterpenoid glycosides (D), 18 alkaloids (A) and 10 others (O) were identified. Trigonelline was discovered for the first time in a herbal medicine of Juhe Fang. Furthermore, 68 compounds were identified in vivo including 28 prototype compounds and 40 metabolites. The metabolic characteristics of these components were revealed including identification of new metabolites of 4-hydroxyphenyl ethyl-8-O-[α-L- arabinopyranosyl-(1 → 6)]-β-D-glucopyranoside (PEG) and lirinidine. A total of 43 components from JHFE were absorbed and/or metabolized. The contribution rate of each type of chemical component from JHFE to its lipid-lowering effect from high to low were A, F, PG, PA, D and T.ConclusionThe results of this study showed that JHFE demonstrated a significant lipid-lowering effect in a high-fat diet (HFD)-induced hyperlipidemia mouse model. Specific types of PA, PG, F, D, T and A formed the pharmaceutical architecture of the lipid-lowering effect of JHFE. This study should prove useful for clarifying the components responsible for the lipid-lowering effect of JHFE and provide a basis for precision quality control research. 相似文献
12.
目的建立超高效液相色谱串联质谱法(UPLC-MS/MS)同时检测痰液中3种药物异烟肼(isoniazid,INH)、左氧氟沙星(levofloxacin,LFX)和吡嗪酰胺(pyrazinamide,PZA)浓度的方法,冒在为实现临床个体化用药提供帮助。方法痰液样品离心后经甲醇/乙腈蛋白沉淀法预处理后进样液质联用仪进行分析。实验采用的流动相A为含0.1%甲酸的水溶液,流动相B为含0.1%甲酸的乙腈;流速0.35mL·min^-1;采用ACQUITY UPLAC HSS T31.8μm column(2.1mm×100mm,Waters公司)分离;采用电喷零电离源,采用多反应监测(multiple reaction monitoring,MRM)模式对待测物进行正离子扫描检测。此外,本试验盲态收集5例患者的痰液,用该法进行定量分析。结果测得痰液中INH、PZA和LFX分别在48~6000 ng·mL^-1(r=0.9988)、480~60000 ng·mL^-1(r=0.9993)、120~15000 ng·mL^-1(r=0.9995)内表现出良好的线性关系。INH、PZA和LFX 3种药物的日内和日间精密度均低于15%,且3种药物的提取回收率均处于97.21%~107.80%之间。7例受试者体内均检测到药物INH,质量浓度分别为44.74、120.1、301.5、481、595.5、1220及1570 ng·mL^-1;PZA的质量浓度分别为104.2、6273.34和3185 ng·mL^-1;1例受试者检出LFX,质量浓度为199.86 ng·mL^-1。结论本试验建立了痰液中INH、PZA及LFX的检测方法,具有灵敏度高、测定结果准确、快速等诸多优点,可以应用于临床治疗药物的监测。 相似文献
13.
目的: 评估液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)分析人全血中环孢素的基质效应,并探究其发生机理。方法: 全血裂解物的蛋白沉淀上清液用作全血基质。分别用乙腈水溶液和全血基质配制等浓度环孢素A(CyA)、环孢素C(CyC)的质控样品。分别在添加H+、NH4+和Na+的流动相中,用LC-ESI-MS/MS的MRM模式检测质控样品中CyA,CyC的[M+H]+、[M+NH4]+和[M+Na]+(M=CyA,CyC)峰面积,以其计算基质效应因子;用MS Scan模式检查质控样品中CyA、CyC色谱流出峰的质谱离子组成情况,用于判断基质效应原因。结果: 在添加H+、NH4+和Na+的流动相中,全血基质中CyA、CyC基质效应因子分别为-76.6%~-54.0%、-86.0%~-55.3%和-42.8%~-34.1%。在加H+、加NH4+流动相中,标准液加全血基质的CyA、CyC色谱峰的质谱中出现丰度很高的[M+Na]+和[M+K]+,在加Na+流动相中它们出现丰度很高的[M+K]+,而对应的定量离子[M+H]+、[M+NH4]+或[M+Na]+的丰度显著降低。结论: 全血基质对环孢素的LC-ESI-MS/MS分析产生明显的基质效应,其原因与基质中Na+、K+同添加在流动相中用于辅助电离的H+、NH4+或Na+竞争与环孢素加合,导致定量目标加合离子丰度显著降低有关。 相似文献
14.
目的探讨川芎⁃天麻配伍对川芎中川芎嗪、阿魏酸在大鼠脑内药动学的影响。方法18只大鼠随机分成川芎组、川芎⁃天麻(1∶0.25)组、川芎⁃天麻(1∶1)组,每组6只,建立血瘀型偏头痛模型。灌胃给药后,于大鼠脑内插入微透析探针,收集不同时间点脑透析液,UPLC⁃MS/MS法检测川芎嗪、阿魏酸含有量,绘制血药浓度⁃时间曲线,计算药动学参数。结果与单味药组比较,配伍组2种成分T1/2[川芎⁃天麻(1∶1)组阿魏酸除外]、MRT0~∞、Cmax、AUC0~∞升高(P<0.05,P<0.01);川芎⁃天麻(1∶0.25)组两者T1/2、MRT0~∞、AUC0~∞高于川芎⁃天麻(1∶1)组(P<0.05,P<0.01),川芎嗪Cmax降低(P<0.05)。结论天麻可提高川芎中川芎嗪、阿魏酸脑组织吸收程度,延长作用时间,减缓消除速率,增加蓄积,其作用强度与天麻剂量有关。 相似文献
15.
《Journal of Pharmaceutical Analysis》2022,12(4):601-609
A sensitive and rapid liquid chromatography tandem mass spectrometry (LC-MS/MS) method was established for the quantification of total and unbound concentrations of LY3214996, an extracellular signal-regulated kinase inhibitor; abemaciclib, a cyclin-dependent kinase 4/6 inhibitor; and abemaciclib active metabolites, M2 and M20, in human plasma, brain tumor, and cerebrospinal fluid samples. The method was validated over a concentration range of 0.2–500 nM within a total run time of 3.8 min using isocratic elution on a Kinetex™ F5 column. Detection was performed on a Sciex QTRAP 6500+ mass spectrometer employing multiple reaction monitoring mode under positive electrospray ionization. The intra- and inter-batch accuracy as well as the precision of the method for all matrices was within ±20% and ≤20% at the lower limit of quantification, and within ±15% and ≤15% for other quality control levels for all analytes. The unbound fractions of drugs and metabolites in spiked and patient samples were determined using an optimized equilibrium dialysis. The validated method was successfully applied in a phase 0/2 clinical trial to assess the central nervous system penetration of LY3214996 and abemaciclib. 相似文献
16.
17.
Daifei Wang Weibang Yu Lin Cao Chuncao Xu Guoyao Tan Zhongxiang Zhao Min Huang Jing Jin 《Biopharmaceutics & drug disposition》2020,41(1-2):54-63
Salvia miltiorrhiza is one of the most commonly used traditional Chinese medicines in the treatment of cardiovascular and cerebrovascular diseases. Cryptotanshinone (CTS), tanshinone IIA (Tan IIA), dihydrotanshinone I (diTan I), and tanshinone I (Tan I) are the main active compounds in the liposoluble extract of Salvia miltiorrhiza. The differences in the pharmacokinetic and tissue distribution behaviors of the four tanshinones after oral administration of the liposoluble extract of Salvia miltiorrhiza and pure compounds are not clear. This study aims to compare the pharmacokinetics and tissue distribution of the four tanshinones after oral administration of pure tanshinone monomers and the liposoluble extract of Salvia miltiorrhiza. An ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) analysis method was developed for the determination of the four tanshinones. The results showed that the AUC and Cmax of tanshinones in rats receiving the extract of Salvia miltiorrhiza were significantly increased compared with those receiving the pure tanshinones. In the tissue distribution experiments, the AUC of the four tanshinones in the extract was much greater than the AUC of the monomers in the lung, heart, kidney, liver, and brain, and the coexisting constituents particularly promoted the distribution of tanshinones into tissues that the drug cannot sufficiently penetrate. These findings suggested that the coexisting constituents in the liposoluble extract of Salvia miltiorrhiza play an important role in the alteration of plasma concentration and tissue distribution of the four tanshinones. Understanding these differences could be of significance for the development and application of Salvia miltiorrhiza extract and tanshinone components. 相似文献
18.
目的:检测头孢丙烯干混悬剂中的未知杂质,并对其进行结构鉴定。方法:采用高效液相色谱-串联高分辨质谱法检测并鉴定头孢丙烯干混悬剂中的未知杂质。色谱柱为Thermo HyPURITYTMC18,流动相为乙腈-0.013%甲酸水溶液(梯度洗脱),检测波长为230 nm,流速为1.0 m L/min,柱温为40℃,进样量为20μL;以电喷雾离子源行正离子全扫描,扫描范围为质荷比(m/z)100~1500,喷雾电压为3.8 kV,金属毛细管温度为320℃,鞘气压力为60 Arb,辅助气压力为10 Arb,喷雾温度为280℃。结果:在该色谱条件下,杂质K的检测限为0.202μg/mL,精密度、重复性试验的RSD均小于4%。杂质K附近发现3个未知杂质,且互为异构体,离子保留时间为17.83~19.31 min,二级母离子均为m/z 436.1500[M+H]+,可能为头孢丙烯开环、脱水后的产物。结论:本方法检测出头孢丙烯干混悬剂中杂质K附近的3个未知杂质。 相似文献
19.
目的:降香为我国传统名贵中药材,然目前市场上降香来源品种复杂,质量差异较大,为进一步明确其药效物质基础,采用超高效液相色谱-串联四极杆飞行时间高分辨率质谱(UPLC-Q-TOF-MS/MS)技术快速分析降香甲醇提取物中的化学成分。方法:采用UPLC RRHD SB-C18色谱柱(3.0 mm×100 mm,1.8μm),以0.1%甲酸水溶液-乙腈为流动相进行梯度洗脱,流速0.3 mL·min^-1,柱温40℃;采用电喷雾离子源,负离子模式采集数据。结果:通过一级精确荷质比和二级碎片信息数据,结合文献资料,质谱裂解规律,Mass bank质谱数据库及对照品的保留时间等,从降香的甲醇提取物中初步鉴定83个化学成分,包括18个黄酮类,31个异黄酮类,10个新黄酮类,9个异黄烷类,7个其他类型黄酮和8个其他类成分。结论:UPLCQ-TOF-MS/MS技术方法可快捷、准确、较全面地鉴定降香甲醇提取物中的化学成分,降香的主要化学成分为异黄酮、黄酮、新黄酮、异黄烷等黄酮类,为降香的药效物质基础研究奠定基础,也为降香药材的质量标准提升提供理论依据和技术支持。 相似文献
20.
目的 测定不同来源的4种大宗常用中药饮片中黄曲霉毒素(AFB1、AFB2、AFG1和AFG2)的含量,比较不同基质中药饮片中黄曲霉毒素的分布状况。方法 基于免疫亲和柱净化-高效液相色谱分离-荧光检测器(IAC-HPLC-FLD)方法,分析不同产地共75批中药样品。结果 柏子仁、薏苡仁、决明子及党参共计75批中药饮片中,阳性检出:26批柏子仁(AFs 1.22-46.67 μg·kg-1,AFB1 1.22-31.40 μg·kg-1)、4批薏苡仁(AFs 1.97-41.13 μg·kg-1,AFB1 1.97-36.40 μg·kg-1)、1批决明子(AFs 13.65 μg·kg-1,AFB1 12.60 μg·kg-1),阳性率41%,超标率15%。阳性样品经 LC-MS/MS确证,排除假阳性。4种大宗常用中药饮片柏子仁、薏苡仁、决明子、党参中黄曲霉毒素的污染水平依次降低,阳性检出率分别为77%、29%、7%、0%,表明中药材中黄曲霉毒素的污染状况与药材基质密切相关。结论 针对易污染AFs的中药品种,需进一步加强其污染状况的全面检测分析,为黄曲霉毒素的有效防控以及完善中药的质量标准提供科学依据,从而保障中药用药安全。 相似文献