9种注射用辅料对肝脏有机阴离子转运多肽OATP1B1和OATP1B3的影响

目的 研究9种注射用辅料对HepG2细胞上OATP1B1和OATP1B3转运体的影响。方法 采用噻唑蓝法考察9种注射用辅料对HepG2细胞存活率的影响;实时荧光聚合酶链反应法以及蛋白质印迹法测定辅料对HepG2细胞中OATP1B1和OATP1B3 mRNA及蛋白表达量的影响;以匹伐他汀作为探针底物,用LC-MS/MS法检测细胞摄取实验中匹伐他汀的胞内蓄积量。结果 Tween80和大豆油能显著性下调HepG2细胞内OATP1B1 mRNA和蛋白表达,甘露醇仅能下调OATP1B1 mRNA的表达量而对蛋白表达无影响;Tween20、Tween80、蔗糖、PEG600和PEG4000能显著下调HepG2细胞内OATP1B3 mRNA和蛋白的表达;PEG600和PEG4000能显著降低HepG2细胞内匹伐他汀的蓄积量。结论 PEG600和PEG4000能通过抑制OATP1B3mRNA和蛋白表达而减少匹伐他汀在HepG2细胞上的摄取量。     

6种药物对有机阴离子转运多肽OATP1B1及其基因多态性A388G、T521C转运作用的影响

目的 研究6种药物对有机阴离子转运多肽OATP1B1及其基因多态性A388G、T521C转运作用的影响。方法 体外培养稳定高表达OATP1B1和OATP1B1基因多态性A388G、T521C的人胚肾细胞（HEK293）株,高表达空白载体（Mock）的HEK293细胞为空白对照,实时荧光定量PCR（qRT-PCR）法检测各转运体细胞中mRNA表达;放射性标记化合物³Hestrone sulfate作为转运底物、利福平作为阳性抑制剂验证各高表达细胞的转运活性;测定30 μmol·L^-1的达比加群、辛伐他汀、替格瑞洛、卡培他滨、多西他赛、依那普利对各细胞³H-estrone sulfate摄入活性的抑制作用,并依据抑制试验结果,进一步测定辛伐他汀、替格瑞洛、多西他赛对转运体细胞的半数抑制浓度（IC₅₀）。结果 HEK293细胞内导入的各种转运体基因都呈现良好的复制表达;OATP1B1、OATP1B1/A388G、OATP1B1/T521C对底物³H-estrone sulfate（5 μmol·L^-1）的转运活性分别为Mock细胞的39、49和48倍,30 μmol·L^-1利福平添加后,可将细胞的转运活性抑制到50%以下;辛伐他汀、替格瑞洛、多西他赛对OATP1B1的抑制作用较强,30 μmol·L^-1给药的转运活性分别为对照组的（40.09±1.95）%、（33.82±0.61）%、（45.08±0.22）%;辛伐他汀对OATP1B1、OATP1B1/A388G、OATP1B1/T521C的IC₅₀分别为14.2、＞100、＞100 μmol·L^-1,替格瑞洛的IC₅₀分别为19.1、68.4、＞100 μmol·L^-1,多西他赛的IC₅₀分别为17.6、22.9、19.3 μmol·L^-1。结论 OATP1B1基因多态性在一定程度上改变了抑制剂对转运体活性的影响程度。     

齐墩果酸对OATP1B1介导药物转运功能的关联性影响

目的 探讨齐墩果酸对有机阴离子转运多肽1B1（organic anion transporting polypetide1B1,OATP1B1）转运功能的关联性影响。方法 利用稳定表达人OATP1B1的人胚胎肾293（hunan embyonic kindney293,HEK293）细胞株,以氟伐他汀为底物进行OATP1B1摄取反应,观察齐墩果酸对OATP1B1摄取功能的影响。结果 齐墩果酸对OATP1B1摄取氟伐他汀的功能有竞争性抑制作用,抑制常数Ki值为（20.3±2.1）mmol·L^-1。结论 齐墩果酸对肝脏药物转运体OATP1B1转运抑制作用可诱导中西药相互作用。     

HMG—CoA还原酶抑制药与转运体OATP1B1

长期以来药物代谢一直被认为是药物分布过程中的主要决定因素。然而，近年来的研究不断证实膜转运体也具有同样重要的作用。事实上，许多外向转运体如MDR1基因编码的P糖蛋白在药物体内分布和药物效应方面的作用已被广泛而深入的加以研究。一些药物在胃肠道、肝和肾脏等许多器官的定向运动中需要内向和外向转运体来协调转运。例如，在外向转运体介导的药物代谢和经胆道排泄之前，分布在肝细胞基底膜上的内向转运体一一有机阴离子转运体超家族（organic anio-transporting polypeptides，OATPs），可促进药物在细胞内集聚。     

以OATP1B1/OATP1B3转运体为作用靶点的何首乌肝毒性成分筛选

目的 建立以有机阴离子转运多肽1B1（OATP1B1）和OATP1B3为作用靶点的何首乌肝毒性成分快速筛选方法。方法 使用Discovery Studio 2.5软件将何首乌主要单体成分（48个）与OATP1B1/OATP1B3蛋白进行分子对接,以OATP1B1和OATP1B3主要转运底物胆红素作为阳性对照,对目标化合物进行虚拟筛选;采用CCK-8法考察芦荟大黄素-8-O-β-D-葡萄糖苷（AEG）、大黄素-8-O-β-D-葡萄糖苷（EG）、大黄素甲醚-8-O-β-D-葡萄糖苷（PG）、2,3,5,4''-四羟基二苯乙烯-2-O-β-D-葡萄糖苷（TSG）处理24 h后对人源肝永生化肝细胞HepaRG的毒性强弱,并采用实时荧光定量PCR （qRT-PCR）技术测定4种化合物对HepaRG细胞的OATP1B1和OATP1B3 mRNA表达量的影响。结果 与OATP1B1对接结果显示,polygonumnolide B3、cis-emodin-physcionbianthrones、polygonumnolide B2、大黄素甲醚-8-β-D-（6''-O-乙酰基）-葡萄糖苷、trans-emodin-physcionbianthrones、大黄素-3-甲醚-8-O-β-D-葡萄糖苷、polygonumnolide B4、大黄酚-8-O-葡萄糖苷、EG、大黄素-1-O-β-D-葡萄糖苷、AEG、大黄酚-8-O-β-D-葡萄糖苷、大黄酸-8-O-葡萄糖苷高于胆红素打分值的80%,可被初步认定为潜在毒性成分;与OATP1B3对接结果显示,trans-emodin-physcionbianthrones、PG、polygonumnolide A4及虎杖苷高于胆红素打分值的80%,可被初步认定为潜在毒性成分。CCK-8实验进一步证实AEG、EG及PG均具肝细胞毒性作用,半数抑制浓度分别为16.10、49.43、69.44 μg·mL^-1,与分子对接结果一致。与对照组比较,AEG、EG均可显著下调OATP1B1的mRNA表达水平（P<0.05）;PG可显著下调OATP1B3的mRNA表达水平（P<0.05）。结论 以OATP1B1/OATP1B3分子对接技术为切入点,可有效预测何首乌潜在肝毒性成分,实现快速高效的高通量筛选,为中药安全性评价提供新思路。     

OATP1B1转运体的基因多态性与瑞舒伐他汀的关联研究

心血管疾病的发病率呈现逐年上升的趋势,其中高脂血症早已成为一种全球性的高发病[1].他汀类药物为HMG-CoA还原酶抑制剂,大量的临床资料表明:应用他汀类药物能明显调低血脂水平,同时显著降低冠心病人群和其它心、脑血管疾病的发生率及病死率,故该类药物在临床上应用非常广泛.     

药物转运体有机阴离子转运多肽1B1基因多态性的研究进展

有机阴离子转运多肽1B1(OATP1B1)是肝脏中重要的药物转运通路之一,其遗传多态性可改变药动学参数,影响多种药物在体内的分布,继而影响药效及药物不良反应. 该文对OATP1B1结构与功能,OATP1B1编码基因的结构及多态性对功能的影响,SLCO1B1多态性对他汀类药物的影响,SLCO1B1多态性对口服降糖药的影响,SLCO1B1多态性对抗肿瘤药的影响等进行综述.     

有机阴离子转运多肽1B1的遗传药理学进展

人体存在多种类型的药物转运体,对于药物的吸收、分布和排泄起重要作用。参与药物跨膜转运的转运体功能受影响,将可能导致诸多临床药物的疗效、毒副作用甚至药物相互作用的发生。在各种影响因素中,遗传多态性所起的作用最为重要,可导致基因表达和蛋白功能发生改变。目前,阐明转运体基因的多态性以及基因型与表型之间的相互关系已成为应用遗传信息指导临床个体化用药的必要步骤。本文就肝脏有机阴离子转运多肽1B1（OATP1B1[OATP-C],编码基因SLCO1B1）基因多态性对药代动力学和药效动力学的影响及其临床意义等方面的进展作一综述。     

有机阴离子转运多肽1B1（OATP1B1）基因多态性对他汀类药物影响的研究进展

有机阴离子转运多肽1B1(OATP1B1)是一种负责转运多种内外源性物质进入肝细胞发挥作用的摄入型转运蛋白。他汀类药物又称3-羟基-3-甲基戊二酸单酰辅酶A(HMG-CoA)还原酶抑制剂,临床上广泛应用于调脂及心脑血管疾病的预防,其疗效及不良反应有显著的个体化差异。研究表明OATP1B1基因多态性是导致他汀类药物个体化差异的重要因素。对OATP1B1基因多态性对他汀类药物影响的研究进展进行综述,为他汀类药物的个体化、安全化应用提供可能的理论指导。     

有机阴离子转运多肽1B1对2型糖尿病药物治疗的影响

目的:了解有机阴离子转运多肽1B1(OATP1B1)对2型糖尿病药物治疗的影响。方法:查阅近年来国内外相关文献,就OATP1B1的影响机制、对那格列奈和瑞格列奈等药物的影响、其他基因组信息进行归纳和总结。结果:OATP1B1对那格列奈和瑞格列奈的体内过程影响明显,人类OATP1B1编码基因(SLCO1B1)521T>C位点的突变对那格列奈药动学和药效学的影响与野生型对照组比较,差异有统计学意义;OATP1B1对瑞格列奈药动学影响呈剂量依赖关系。SLCO1B1 388A>G位点的突变对2型糖尿病药物的体内过程影响不明显。结论:OATP1B1作为摄入型转运体在糖尿病的药物治疗中起重要作用。患者的基因组信息将成为2型糖尿病患者临床合理用药的重要参考因素,有必要对OATP1B1进行更深入、系统的研究。     

Effects of natural products on the function of human organic anion transporting polypeptide 1B1

In this study, the effects of 136 naturally occurring products, which have been reported to play important roles in modification of Cytochrome P450 (CYP450) activities, on the uptake of estrone-3-sulfate (E3S), a typical OATP1B1 substrate, were evaluated using human embryonic kidney 293 cells stably expressing OATP1B1. At a concentration of 100 μM, 42 natural products inhibited OATP1B1-mediated [(3)H]E3S uptake by more than 50%, and five of them significantly inhibited OATP1B1-mediated [(3)H]E3S by more than 80% with the following rank order of potency: quercetin > astragaloside IV > icariin > glycyrrhizic acid > ginsenoside Rc. Inhibitory effects of these natural products on OATP1B1 activity were in a concentration-dependent manner. 11 natural compounds were found exhibiting greater than 50% inhibition at 30 μM with IC(50) values ranging from 14.6 ± 3.3 to 28.5 ± 3.0 μM. In conclusion, our data suggest that modification of OATP1B1 transport activity by these natural occurring products may be a mechanism for natural product-drug interactions in humans.     

有机阴离子转运多肽1B3的研究进展

有机阴离子转运多肽1B3(organic anion transporting polypeptide 1B3,OATP1B3)属于溶质转运体(solute carrier,SLC)超家族,主要负责将内、外源物质转运至肝细胞代谢。OATP1B3是肝脏特异性转运体,通常局限性地分布于肝细胞窦状隙侧肝细胞膜上,近期研究发现在前列腺癌、结肠癌、肺癌等肿瘤组织和细胞中也存在着高表达。溶质转运体1B3(SLCO1B3)具有明显的基因多态性,334T>G和699G>A单体型可明显影响OATP1B3的转运活性,从而介导药物-药物相互作用的发生,导致临床用药的个体差异。此外,OATP1B3可通过作用于孕烷X受体(pregnane X receptor,PXR)和组成性雄甾烷受体(constitutive androstane receptor,CAR)等核受体配体的转运,影响体内PXR和CAR的转录活性,从而调控药物代谢酶如细胞色素P450 3A4(CYP3A4)的表达。本文将对OATP1B3近年来的研究进展进行综述。     

Influence of the flavonoids apigenin, kaempferol, and quercetin on the function of organic anion transporting polypeptides 1A2 and 2B1

OATP1A2 and OATP2B1 are uptake transporters of the human organic anion transporting polypeptide (OATP) family with a broad substrate spectrum including several endogenous compounds as well as drugs such as the antihistaminic drug fexofenadine and HMG-CoA reductase inhibitors. Both transporters are localized in the apical membrane of human enterocytes. Flavonoids, abundantly occurring in plants, have previously been shown to interact with drug metabolizing enzymes and transporters. However, the impact of flavonoids on OATP1A2 and OATP2B1 transport function has not been analyzed in detail. Therefore, HEK293 cell lines stably expressing OATP1A2 and OATP2B1 were used to investigate the influence of the Ginkgo flavonoids apigenin, kaempferol, and quercetin on the transport activity of OATP1A2 and OATP2B1. K_i values of all three flavonoids determined from Dixon plot analyses using BSP as substrate indicated a competitive inhibition with quercetin as the most potent inhibitor of OATP1A2 (22.0 μM) and OATP2B1 (8.7 μM) followed by kaempferol (OATP1A2: 25.2 μM, OATP2B1: 15.1 μM) and apigenin (OATP1A2: 32.4 μM OATP2B1: 20.8 μM). Apigenin, kaempferol, and quercetin led to a concentration-dependent decrease of the OATP1A2-mediated fexofenadine transport with IC₅₀ values of 4.3 μM, 12.0 μM, and 12.6 μM, respectively. The OATP1A2- and OATP2B1-mediated transport of atorvastatin was also efficiently inhibited by apigenin (IC₅₀ for OATP1A2: 9.3 μM, OATP2B1: 13.9 μM), kaempferol (IC₅₀ for OATP1A2: 37.3 μM, OATP2B1: 20.7 μM) and quercetin (IC₅₀ for OATP1A2: 13.5 μM, OATP2B1: 14.1 μM). These data indicate that modification of OATP1A2 and OATP2B1 transport activity by apigenin, kaempferol, and quercetin may be a mechanism for food-drug or drug-drug interactions in humans.     

Stimulatory effect on the transport mediated by organic anion transporting polypeptide 2B1

Drug-drug interaction(DDI)is one of causes of adverse drug events and can result in lifethreatening consequences.Organic anion-transporting polypeptide(OATP)2B1 is a major uptake transporter in the intestine and contributes to transport various clinically used therapeutic agents.The intestine has a high risk of DDI,because it has a special propensity to be exposed to a high concentration of drugs.Thus,understanding drug interaction mediated by OATP2B1 in the absorption process is important for the prevention of adverse drug events,including decrease in the therapeutic effect of co-administered drugs.Acute drug interaction occurs through the direct inhibitory effect on transporters,including OATP2B1.Moreover,some compounds such as clinically used drugs and food components have an acute stimulatory effect on transport of co-administered drugs by OATP2B1.This review summarizes the acute stimulatory effect on the transport mediated by OATP2B1 and discusses the mechanisms of the acute stimulatory effects of compounds.There are two types of acute stimulatory effects,substrate-independent and-dependent interactions on OATP2B1 function.The facilitating translocation of OATP2B1 to the plasma membrane is one of causes for the substrate-independent acute stimulatory effect.On the contrary,the substrate-dependent effect is based on the direct binding to the substrate-binding site or allosteric progesterone-binding site of OATP2B1.     

Substrate-dependent effects of molecular-targeted anticancer agents on activity of organic anion transporting polypeptide 1B1

1. Organic anion-transporting polypeptide 1B1 (OATP1B1) plays an important role in the hepatic uptake of a broad range of substrate drugs. In vitro experiments show that molecular-targeted agents do not always have similar effects on OATP1B1 activity.

2. The purpose of this study was to clarify whether the effects of molecular-targeted agents on OATP1B1 are substrate-dependent. We used OATP1B1-transfected cells to compare the effects of molecular-targeted agents on OATP1B1-mediated uptake of fluorescein (FL), 2′,7′-dichlorofluorescein (DCF), atorvastatin, SN-38 and valsartan.

3. Cabozantinib, cediranib, neratinib, pazopanib, regorafenib, sorafenib and tivantinib did not affect or only slightly affected OATP1B1-mediated substrate uptake. Nilotinib and lenvatinib moderately and strongly inhibited OATP1B1-mediated substrate uptake, respectively. In contrast, afatinib stimulated OATP1B1-mediated uptake of FL and SN-38, ceritinib stimulated that of valsartan, and nintedanib stimulated that of FL and valsartan. In addition, the effects of afatinib, ceritinib and nintedanib on OATP1B1 activity differed markedly depending on the type of substrate. Afatinib, ceritinib and nintedanib had a substrate-dependent effect on OATP1B1 activity.

4. We conclude that the evaluation of OATP1B1 activity using only a single probe substrate for some molecular-targeted agents may lead to a faulty understanding of their mechanisms of drug interactions.     

Insulin stimulates transport of organic anion compounds mediated by organic anion transporting polypeptide 2B1 in the human intestinal cell line Caco-2

Organic anion transporting polypeptide 2B1 (OATP2B1) is the major uptake transporter in the intestine, and transports various clinically used therapeutic agents. Insulin acts through the insulin receptor in targeted cells, and Rab8A is one of the insulin signaling pathways. The small intestine in humans also expresses insulin receptor and Rab8A. It has been reported that insulin stimulates peptide transporter 1 (PEPT1) expression at the apical membrane and increases uptake of PEPT1 substrates in small intestine epithelial model cells (Caco-2 cells). However, the effect of insulin on OATP2B1 in the small intestine has not been fully investigated. We found that Rab8A was associated with OATP2B1-mediated estrone-3-sulfate (E3S) uptake. Insulin stimulated the uptake of E3S by Caco-2 cells and the enhancement was sustained for 120 min. The Vmax value of E3S uptake significantly increased upon insulin exposure. Caco-2 cells treated with insulin showed increased OATP2B1 expression at the cell surface. The apical-to-basal transport of E3S was also increased by insulin. The increase of E3S transport was inhibited by the cold condition (4 °C) or the OATP2B1 inhibitor, taurocholate. These results indicate that insulin acts on the small intestine to increase OATP2B1-mediated absorption.     

大蒜素对HL-60细胞端粒酶活性的影响

目的 研究大蒜素对人早幼白血病HL-60细胞端粒酶活性的影响。方法 不同浓度的大蒜素作用HL-60细胞后,MTT法测细胞的生长和增殖情况,TRAP-PCR-ELISA法研究细胞端粒酶活性的变化。结果 大蒜素能明显地抑制HL-60细胞的生长,且呈时间、浓度依赖性。不同浓度的大蒜素能下调HL-60细胞的端粒酶活性,且同样呈时间、浓度依赖性。结论 大蒜素可抑制HL-60细胞的端粒酶活性,可能是其诱导HL-60细胞凋亡的重要机制之一。     

Functional pleiotropy of organic anion transporting polypeptide OATP2B1 due to multiple binding sites

The purpose of this study was to examine whether the presence of multiple binding sites can explain the pleiotropy of substrate recognition by OATP2B1, using Xenopus oocytes expressing OATP2B1. OATP2B1-mediated uptake of estrone-3-sulfate apparently exhibited biphasic saturation kinetics, with Km values of 0.10 ± 0.05 and 29.9 ± 12.1 μM and Vmax values of 14.1 ± 6.4 and 995 ± 273 fmol/min/oocyte for high- and low-affinity sites, respectively. Contribution analysis revealed that transport of estrone-3-sulfate mediated by high- and low-affinity sites on OATP2B1 could be evaluated at the concentrations of 0.005 and 50 μM, respectively. pH-dependence study of OATP2B1-mediated estrone-3-sulfate uptake suggested that high- and low-affinity sites show different pH sensitivity. When the inhibitory effect of 12 compounds on estrone-3-sulfate uptake by high- and low-affinity sites on OATP2B1 was examined, 4 compounds appeared to be inhibitors of the high-affinity site on OATP2B1. Two other compounds appeared to be inhibitors for the low-affinity site and four others were inhibitory at both sites. These results indicated the presence of multiple binding sites on OATP2B1 with different affinity for drugs. Accordingly, it is likely that drug-drug and drug-beverage interactions occur only when two drugs share the same binding site on OATP2B1.     

Protein kinase C regulates the internalization and function of the human organic anion transporting polypeptide 1A2

BACKGROUND AND PURPOSE

The human organic anion transporting polypeptide 1A2 (OATP1A2) is expressed in cells from several regions of the human body, including the kidney, cholangiocytes and the blood-brain barrier, and mediates the cellular flux of various anionic substances, including drugs in clinical use. Several related mammalian transporters have been shown to be subject to post-translational regulation, including kinase-induced internalization. In the present study the role of protein kinase C (PKC) in the regulation of OATP1A2 was investigated in an in vitro cell model.

EXPERIMENTAL APPROACH

COS-7 cells in which OATP1A2 was overexpressed were treated with the PKC-specific activator (phorbol 12-myristate 13-acetate; PMA) and the PKC-specific inhibitor (Go6976). The impact of these treatments on the function and regulation of OATP1A2 was determined.

KEY RESULTS

PKC activation decreased the transport function of OATP1A2 in a time- and concentration-dependent manner. PMA (0.1 µM) decreased the V_max of oestrone-3-sulphate uptake and decreased the cell surface expression of OATP1A2 immunoreactive protein; these effects of PMA were prevented by the PKC specific inhibitor Go6976. In further studies, PMA treatment accelerated the internalization of OATP1A2 but did not affect its recycling. The disruption of clathrine-dependent endocytosis attenuated both the constitutive and PKC-modulated internalization of OATP1A2. In contrast, blocking the caveolin-dependent pathway was without effect.

CONCLUSIONS AND IMPLICATIONS

PKC regulates the transport function of OATP1A2 by modulating protein internalization; this effect of PKC is mediated in part by clathrine-dependent pathways.     

Organic anion transporting polypeptide-1B1 haplotypes in Chinese patients

Aim： To detect 388G〉A and 521T〉C variant alleles in the organic anion transporting polypeptide- 1B 1 （OATP 1B 1, encoding gene SLCOIB1） gene. Methods： One hundred and eleven healthy volunteers were screened for OATP1B 1 alleles in our study. PCR-restriction fragment length polymorphism was used to identify the 388G〉A polymorphism and a 1-step tetra-primer method was developed for the determination of 521T〉C mutation. Results： The frequencies of the 388G〉A and 521T〉C variant alleles in the Chinese population were 73.4% and 14.0%, respectively. The frequencies of the SLCO1B1＊ 1b and ＊15 haplotypes were 59.9% and 14.0%, respectively. Condusion： The SLCO1B1＊1b and SLCO1B1＊15 variants are relatively common in the Chinese population. Their frequencies are similar to that in the Japanese, but significantly different from that in Caucasians and blacks.