白术内酯类在人源Caco-2细胞单层模型中的肠吸收研究(英文)

采用人源Caco-2细胞单层模型,研究了倍半萜内酯类的白术内酯Ⅰ、Ⅱ和Ⅲ的肠渗透性。研究了它们从顶端到基底侧以及从基底侧到顶端的双向渗透性。HPLC法测定其浓度。白术内酯Ⅰ、Ⅱ、Ⅲ的P_app值皆在10^-5cm/s水平,表明其具有高肠渗透率和良好吸收的特性。它们的双向转运具有时间和浓度依赖性,提示其吸收转运的主要机制为被动扩散。此外,白术内酯Ⅰ的吸收转运可能部分存在主动转运机制。     

Studies of intestinal permeability of 36 flavonoids using Caco-2 cell monolayer model

Quinine is the first line treatment in severe P. falciparum malaria and nocturnal leg cramps and a fast, convenient delivery method of this drug quinine is needed. The purpose of this study was to investigate in vitro the sublingual route for the delivery of quinine. Permeation studies were carried out with Franz diffusion cells containing sublingual mucosa membranes with PBS receptor phase and dosed with solutions of quinine hydrochloride or quinine/2-hydroxypropyl-beta-cyclodextrin complexes. Receptor phase samples were taken 2 hourly over a 12h period and quinine was determined by reverse-phase HPLC analysis. The ventral surface of the tongue was significantly more permeable than porcine floor of the mouth (p<0.05) and there was no significant effect of freezing on the ventral surface of the tongue (p 0.2444). The presence of saliva caused a decrease in the permeation of quinine across the ventral surface of the tongue by up to 68%. Inclusion complexation between quinine and 2-HP-beta-CD was supported by (1)H NMR spectral data, and an ethanol vehicle provided the highest quinine flux from the inclusion complex solutions compared to deionised water and PEG. Overall, the data support further investigations into the clinical use of sublingual quinine, particularly for children with falciparum malaria or patients with nocturnal leg cramps. Use of quinine/cyclodextrin inclusion complexes may circumvent compliance issues due to bitter taste.     

Intestinal transport of pure diester-type alkaloids from an aconite extract across the Caco-2 cell monolayer model

Aconitine (AC), mesaconitine (MA), and hypaconitine (HA) are the active alkaloids identified in aconite tuber, an important traditional Chinese medicine. The study is aimed to investigate their intestinal transport profiles and potential interaction during the intestinal absorption using the Caco-2 cell monolayer model. All three alkaloids had good permeability with P(app) values greater than 1 × 10 (-6) cm · s (-1). However, AC, MA, and HA in a mixture and as an extract, in both cases with the same content of alkaloids, showed higher transport efficiency in the apical to basolateral, and lower transport efficiency in the basolateral to apical directions. Digoxin, as a P-glycoprotein (P-gp) substrate, was substantially effluxed in the basolateral to apical direction but inhibited by the three alkaloids. Furthermore, the backwards transport of MA and HA was inhibited by the P-gp inhibitor verapamil. These observations indicated that the three alkaloids may not only be P-gp inhibitors but also its substrates; they interact with each other and can potentially enhance their own bioavailability when taken concomitantly.     

Intestinal efflux transport kinetics of green tea catechins in Caco-2 monolayer model

The bioavailability of green tea catechins (GTCs), including epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG) and epicatechin (EC) is low in both animals and humans. The contribution of intestinal efflux to this low bioavailability has been suggested by previous studies. The objective of the present study was to investigate the kinetics of efflux transport of the four major GTCs in Caco-2 cell lines, to provide comparison on the efflux transport between each GTC. The basal-to-apical transport of each GTC at concentrations ranging from 15 to 265 microM was examined using the Caco-2 cell monolayer model. Transported amount of GTC was measured by high-performance liquid chromatography with electrochemical detection. Kinetic parameters, V(max), K(m) and V(max)/K(m) were determined and compared among the four studied GTCs. The extent of basal-to-apical transport was, in descending order, EC > EGC > ECG approximately EGCG. Kinetic studies indicated that active and saturable efflux transport of EC took place in Caco-2 cells, with a K(m) of 131 microM, a V(max) of 0.0249 nmol min cm(-2) and an intrinsic clearance (V(max)/K(m)) of 0.19 microL min cm(-2). No saturation could be observed for the efflux transport of EGC, ECG and EGCG even at concentrations up to about 200 microM, which may be due to their low affinity towards the transporters at the concentration range studied. In conclusion, the extent of efflux transport of GTCs in Caco-2 cells was, in descending order, EC > EGC > ECG approximately EGCG, which may reflect the order of elimination occurring in the intestine. The kinetic studies showed the importance of efflux transporters in basal-to-apical transport of EC and suggests their role in the limited oral bioavailability of EC.     

千层纸素A在Caco-2细胞模型中的吸收机制研究

目的研究千层纸素A在Caco-2细胞模型中的吸收机制。方法 MTT实验考察千层纸素A在Caco-2细胞中的安全浓度范围,再利用Caco-2细胞单层模型研究千层纸素A的双向转运机制,以转运量及表观渗透系数(Papp)为指标,考察时间、浓度、pH和P-gp抑制药维拉帕米对其吸收的影响。结果千层纸素A在Caco-2细胞模型中的转运与时间和浓度呈正相关;并受pH值影响,P-gp抑制药维拉帕米对其转运无影响,从单层细胞层顶端(AP)到基底端(BL)的转运与基底端到顶端的转运大致相同。结论千层纸素A在Caco-2细胞模型中的吸收是被动转运。     

Evaluation of an accelerated Caco-2 cell permeability model

An accelerated 3-7-day Caco-2 cell permeability model was examined and compared to the traditional 21-25-day model. Caco-2 cell permeability coefficients (P(Caco-2)) of 33 structurally diverse small molecular weight compounds from apical to basolateral (AP-->BL) direction in the accelerated model were approximately twice those in the traditional model. As observed with microscopy and transepithelial electrical resistance measurements, this difference was attributed to less confluent and differentiated Caco-2 cell monolayers in the accelerated model. However, there were no significant differences in rank ordering of the compounds. The expression of P-glycoprotein in the accelerated model was shown to be significantly less than that in the traditional model. This resulted in lower permeability directional ratios defined as the ratio between permeability coefficients from BL-->AP and from AP-->BL for compounds that were cellular efflux pump substrates. The accelerated model may not be suitable for studying cellular efflux pumps such as P-glycoproteins. However, it is a feasible alternative to the traditional model for rank ordering of compounds in the process of drug discovery and development by significantly improving the turnover time and labor efficiency. This makes it an excellent Caco-2 cell permeability model for high throughput screening.     

Effects of capsaicin on cellular damage and monolayer permeability in human intestinal Caco-2 cells

Recent studies suggest that capsaicin (Cap), a major constituent of hot pepper, may affect the function and permeability of the intestinal mucosa in vitro. However, the relationships between the dose of Cap and the barrier and/or transporter functions on intestinal epithelial cells are unknown. The aim of this study was to investigate whether Cap initiates cellular injury and alter epithelial permeability in Caco-2 cells. Cellular toxicity, as measured using a lactate dehydrogenase release assay, was not observed at high concentrations of Cap (up to 300 microM). When cell viability was measured by a WST-1 assay (tetrazolium salt-based assay), damage to Caco-2 monolayers was observed at doses of 200 and 300 microM of Cap. The barrier function of tight junctions was assessed by measuring transepithelial electrical resistance (TEER) in Caco-2 cells. Treatment of Caco-2 cells with Cap at doses above 100 microM significantly decreased the TEER compared to treatment with buffer alone for 2 h (p<0.05). We next examined the effects of Cap on the activity of P-glycoprotein (P-gp) found on transcellular transporters. At doses of 100 and 200 microM, Cap inhibited the transport of rhodamine 123 by P-gp-mediated efflux in Caco-2 cells. Cap thus exhibited inhibitory effects on P-gp. The results of this study indicate that Cap, a dietary phytochemical, causes functional and structural changes in Caco-2 cell monolayers at noncytotoxic doses (less than 100 microM of Cap). The concomitant administration of Cap with drugs that are substrates of P-gp might increase the plasma concentrations of such drugs.     

Characterization of metabolites in Saposhnikovia divaricata root from Mongolia

Journal of Natural Medicines - Saposhnikoviae Radix (SR), derived from the dried root and rhizome of Saposhnikovia divaricata, is a popular crude drug used in traditional Chinese and Japanese...     

Intestinal absorption of Stemona alkaloids in a Caco-2 cell model

The intestinal absorption of neotuberostemonine and neostenine, two major bioactive alkaloids of the commonly used antitussive traditional Chinese medicine Stemona tuberosa Lour, was investigated using a Caco-2 monolayer model. Both alkaloids exhibited a high absorptive permeability which was higher for neostenine [P(app(AB)) = 12.03 +/- 1.14 x 10 (-6) cm/s] than for neotuberostemonine [P(app(AB)) = 9.27 +/- 0.79 x 10 (-6) cm/s], indicating that they are likely to be well absorbed and orally active. Furthermore, both alkaloids were identified to be the substrates of P-glycoprotein and have a transport preference from the basolateral to apical direction with efflux ratios between 2 and 3. Cyclosporin A dose-dependently inhibited the secretory permeability of these alkaloids and abolished their active efflux transport.     

肠道转运Caco-2细胞单层模型的建立及验证评价

目的建立Caco-2细胞单层模型用于药物转运研究。方法按照常规的细胞培养方法,将Caco-2细胞接种到Millicell小室内(接种密度1×10⁶个·mL^-1),培养21 d。定期用细胞电位仪监测跨上皮细胞电阻（TEER）,评价细胞单层的紧密性与完整性;通过荧光黄转运实验检查Caco-2细胞单层模型细胞旁路转运通透性;通过普萘洛尔转运实验验证Caco-2细胞单层模型跨细胞被动转运通透性。结果培养21 d后,TEER值达到（981±123）Ω·cm²,荧光黄和普萘洛尔的表观通透系数分别为0.33×10及16.7×10^-6cm·s^-1。结论本研究建立的Caco-2细胞单层模型紧密、完整,具有良好通透性,可用于药物转运研究。     

赤芍提取物中两种主要成分在Caco-2细胞中的摄取特性研究

<正>赤芍为毛莫科植物川赤芍Paeonin veitchii Lynch的干燥根,具有清热凉血、散癖止痛等功效。现代药理研究表明,赤芍具有扩张血管、解热解痉、抗血栓形成等药理作用。芍药苷是芍药总苷的主要成分~([1]),具有赤芍上述的药理功效,但研究发现芍药苷的胃肠吸收很差,生物利用度低~([2]),限制了其临床应用。本研究利用Caco-2细胞模型~([3-4])对赤芍主要成分芍药苷、苯甲酰芍药苷进行体外吸收特性的初步研究,     

高效液相色谱法考察更昔洛韦在Caco-2细胞上的转运特征

目的:建立更昔洛韦的高效液相色谱测定法,研究其在Caccr2细胞上的转运特征.方法:采用Eurospher-100 C18(250 mm×4.6 mm,5μm)色谱柱,流动相为甲醇-水(8∶92),流速为1.0 mL·min-1,检测波长为254 nm,考察介质pH、药物浓度、P-gp抑制剂对更昔洛韦在Caco-2细胞上转运的影响.结果:更昔洛韦在Caco-2细胞单层膜上的转运量具有一定的浓度和时间依赖性,但介质pH对其跨膜转运无显著影响;更昔洛韦在50 mg·L-1质量浓度下AP→BL、B→AP方向转运表现渗透系数分别为(0.59±0.11)×10-6和(2.0±0.4)×10-6cm·s-1.P-gp抑制剂维拉帕米能够增加更昔洛韦跨膜转运量.结论:更昔洛韦在Caco-2细胞上转运表现为被动扩散且有外转运蛋白参与更昔洛韦跨膜转运.     

阿立哌唑在Caco-2细胞单层模型中的跨膜转运

本文研究了阿立哌唑（aripiprazole）在Caco-2细胞模型中的跨膜转运特征。一种体外培养的人小肠上皮细胞模型 —— Caco-2细胞模型应用于阿立哌唑的跨膜转运研究。评价了时间、供给液浓度、pH值、温度及P-糖蛋白抑制剂对阿立哌唑跨膜转运的影响。采用高效液相色谱法检测药物浓度。结果表明阿立哌唑主要通过被动扩散的机制转运,同时兼有载体介导转运。阿立哌唑的转运量与时间、pH值、温度成正相关。表观渗透系数P_app值随供给液浓度升高而增大,10 μg·mL^-1时趋向饱和,之后随阿立哌唑浓度的增加而逐渐减小。P-糖蛋白抑制剂环孢菌素-A显著增加阿立哌唑的跨膜转运。     

Estimation of the human intestinal permeability of butyltin species using the Caco-2 cell line model.

The main objective of the work was the setup of the Caco-2 human intestinal cell-line model for the study of the intestinal permeation of monobutyltin (MBT), dibutyltin (DBT) and tributyltin (TBT). The study was focused in gathering information on (a) the relative permeability of butyltins, (b) their possible permeation routes (paracellular/transcellular) and (c) the eventual interactions between the different butyltins when occurring as a mixture. The presence of basolateral serum protein greatly influenced the permeability, causing a large net clearance, but the apparent permeability (Papp) values were comparable to that of phenolred, suggesting a low in vivo permeability of the butyltins. The found permeability pattern correlates well with the general in vivo toxicity pattern (trialkyltin>dialkyltin>monoalkyltin). The accumulation pattern (DBT>TBT>MBT) was different from that of permeability and may be an important element regarding the elucidation of some specific strong toxic effects caused by the dialkyltins in several species. The transport of MBT and DBT was found to be dependent on the paracellular route status. An interaction between the butyltin compounds in a mixture was found for the accumulation results (the accumulation was significantly higher for the three compounds when in a mixture). A set of useful information about the butyltin accumulation and transport by the epithelial Caco-2 cell line was, thus, achieved, constituting a starting point for future research on the permeability of butyltins from contaminated food and beverages.     

噻吩诺啡在Caco-2细胞上的转运特征

目的探讨噻吩诺啡在Caco-2细胞上的转运特征及其对P-糖蛋白(P-gp)功能和表达的影响。方法采用高效液相色谱-质谱-质谱法测定噻吩诺啡浓度,研究噻吩诺啡在单层细胞中的双向转运,考察时间及转运蛋白抑制剂对噻吩诺啡在Caco-2细胞上转运的影响;流式细胞仪检测胞内钙黄绿素-AM浓度,评价噻吩诺啡对P-gp的抑制作用;采用Western蛋白印迹法检测P-gp表达。结果噻吩诺啡通过Caco-2单层细胞的转运量在1.5h内随时间延长呈线性增加,表观渗透系数(Papp)2.338×10-6cm.s-1;加入P-gp及多药耐药相关蛋白2(MRP2)抑制剂环孢素A和MK571后分别提高2.8和2.3倍;在噻吩诺啡作用下,胞内钙黄绿素-AM浓度无显著变化,P-gp表达无显著增加。结论噻吩诺啡在Caco-2细胞吸收中等偏差,是P-gp和MRP2的共同底物,噻吩诺啡对P-gp无诱导或抑制作用。     

以Caco-2细胞模型研究远志皂苷水解物的肠吸收特性

目的 通过研究远志皂苷水解物主要活性成分3,4,5-三甲氧基肉桂酸(TMCA)、对甲氧基肉桂酸(PMCA)和细叶远志皂苷(TF)的肠转运特性,预测其口服生物利用度.方法 利用Caco-2细胞模型,以及所建立的LC-MS/MS分析方法,研究上述3个成分在不同浓度下从顶侧(AP)到基底侧(BL)以及从BL到AP2个方向的转运特性.结果 TMCA和PMCA 2个酚酸化合物具有较好的膜通透性,在不同浓度下从AP到BL的表观渗透系数(Papp)均＞10×10-6cm·s-1,而三萜皂苷TF的通透性较差,Papp值均＜1×10-6cm· s-1.3个化合物的转运量均随浓度的增加而增加,但Papp值保持基本一致,且各自2个方向的Papp值无明显差异.结论 TMCA和PMCA具有良好的肠通透性,属吸收较好的化合物,而TF则通透性较差,口服吸收可能很有限;3个化合物均以被动扩散形式转运,且无外排转运机制.     

灯盏细辛提取物中3种活性成分在Caco-2细胞模型吸收机制的研究

目的研究灯盏细辛提取物(erigeron breviscapus extract,Ebe)中3种活性成分灯盏甲素、咖啡酸和绿原酸的吸收机制。方法建立人结肠腺癌细胞系(the human colon carcinoma cell line,Caco-2细胞)模型;利用该模型研究Ebe的细胞摄取规律,通过UPLC-MS/MS法测定Caco-2细胞中灯盏甲素、咖啡酸和绿原酸的浓度,研究pH、时间以及药物浓度对3种活性成分的转运影响;考察在P-糖蛋白抑制剂(维拉帕米、环孢素A)存在与否时3种活性成分在Caco-2细胞模型中的转运情况。结果受试物Ebe在所设置的浓度范围内(0.1~25.0 g·L~(-1))对Caco-2细胞无毒副作用。灯盏甲素和绿原酸在Caco-2细胞摄取实验中具有浓度、时间依赖性,呈正相关,渗透系数维持在一个平衡状态。咖啡酸具有浓度饱和性,且加入P-糖蛋白抑制剂后咖啡酸的细胞摄取量明显增加。结论 Ebe中灯盏甲素和绿原酸主要表现为被动转运,P-糖蛋白参与了咖啡酸的摄取过程,咖啡酸的吸收主要由载体媒介转运实现。     

杜仲提取物中4种主要成分在Caco-2细胞的摄取特性研究

目的研究杜仲提取物中京尼平苷酸、原儿茶酸、松脂醇二葡萄糖苷、松脂醇单葡萄糖苷在Caco-2细胞的摄取特性。方法以Caco-2细胞单层模型研究杜仲提取物的细胞摄取规律,采用UPLC-MS/MS法测定Caco-2细胞中京尼平苷酸、原儿茶酸、松脂醇二葡萄糖苷、松脂醇单葡萄糖苷的浓度,考察时间、pH值、药物浓度、温度及抑制剂对Caco-2细胞摄取杜仲提取物的影响。结果杜仲提取物中京尼平苷酸、原儿茶酸、松脂醇二葡萄糖苷、松脂醇单葡萄糖苷4种成分在Caco-2细胞中的摄取具有一定的时间、浓度依懒性,其摄取表现为被动扩散;在pH 4条件下,杜仲提取物中上述4种成分的细胞摄取量明显高于pH 8;在4℃、25℃、37℃条件下,杜仲提取物在37℃下的摄取量最高;加入维拉帕米、环孢菌素A后,杜仲提取物中原儿茶酸的细胞摄取量有明显变化,其余3个成分没有变化。结论杜仲提取物中京尼平苷酸、原儿茶酸、松脂醇二葡萄糖苷、松脂醇单葡萄糖苷4种成分的细胞摄取机制主要是被动转运;P-糖蛋白参与其原儿茶酸的摄取过程。     

利用Caco-2细胞单层模型评价P-糖蛋白对安妥沙星转运的影响

目的 评价P-糖蛋白抑制剂酮康唑对安妥沙星转运的影响.方法 利用人源结肠腺癌系Caco-2细胞单层模型对安妥沙星进行双向转运,采用高效液相色谱法对安妥沙星进行定量分析,计算其表观渗透系数(Papp).结果 加入酮康唑后,低浓度安妥沙星(100μmol/L)Papp(B-A)/Papp(A-B)由4.12降至1.23(P＜0.01),高浓度安妥沙星(500μmol/L)Papp(B-A)/Papp(A-B)由3.54降至1.22(P＜0.01).结论 安妥沙星在Caco-2细胞单层模型中的转运机制可能以主动转运为主,P-糖蛋白参与其从细胞基底侧向管腔面的分泌.