著者
Qubo Zhu Zhifang Liu Pei Li Zeneng Cheng
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
pp.DMPK-13-RG-123, (Released:2014-02-11)
参考文献数
30
被引用文献数
9

Hypothesis: Simotinib Hydrochloride (SIM6802), which is a new epidermal growth factor receptor-tyrosine kinases inhibitor (EGFR-TKI), is often prescribed for cancer patients with comorbidities and has serious adverse effects gastrointestinal physiology. The drug-drug interactions (DDI) between simotinib and other drugs in combination and the underlying mechanism of its gastrointestinal toxicity remains unclear. We hypothesized that the DDI and the gastrointestinal toxicity of simotinib was related to its effects on the permeability of intestine. Methods: To determine the intestinal absorption ability, pharmacokinetic studies and in situ loop assay were used. The intestinal permeability was measured by Caco-2 transwell model. Real time PCR and western blots were applied to detecting the expression changes of cell junction genes. Results: Our research demonstrated that simotinib upregulated the absorption of cefaclor, valaciclovir and acyclovir. The increase of non-selective absorption was caused by the low expression of cell junction gene afadin-6 and the increasing of paracellular permeability in intestinal epithelial cells after simotinib treatment. Conclusion: These findings revealed that simotinib upregulated intestinal absorption by increasing the paracellular permeability of intestinal epithelial cells. Our research provides theoretical bases for better formulation of EGFR-TKIs to alleviate adverse gastrointestinal effects and also provides guidance for clinical administration of simotinib.
著者
Kaoru KOBAYASHI Eri KAJIWARA Masayuki ISHIKAWA Hanaka MIMURA Hidenobu OKA Yoko EJIRI Masaya HOSODA Kan CHIBA
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.28, no.3, pp.265-268, 2013 (Released:2013-06-25)
参考文献数
18
被引用文献数
14

Treatment with benzbromarone (BBR), a potent uricosuric drug, can be associated with liver injury. Recently, we reported that culture of human hepatocellular carcinoma FLC-4 cells on micro-space cell culture plates could increase the functional expression of drug-metabolizing enzymes including CYP3A4 and CYP2C9, which are involved in 1′-hydroxylation and 6-hydroxylation of BBR, respectively. Therefore, we examined whether BBR and its two metabolites (1′-hydroxy BBR and 6-hydroxy BBR) have cytotoxic effects in FLC4 cells cultured on micro-space cell culture plates. The present study showed that BBR and 1′-hydroxy BBR, but not 6-hydroxy BBR, have cytotoxic effects in cells cultured on micro-space cell culture plates. BBR-induced cytotoxicity was decreased by CYP3A inhibitors (itraconazole and ketoconazole), an Nrf2 activator (tert-butylhydroquinone) and a GSH precursor (N-acetyl-L-cystein). In contrast, BBR-induced cytotoxicity was increased by a GSH biosynthesis inhibitor (buthionine sulfoximine) and an inhibitor of NAD(P)H quinone oxidoreductase 1 (dicoumarol). These results suggested that metabolic activation of 1′-hydroxy BBR via CYP3A, formation of quinone metabolites and the decrease in GSH levels were involved in the BBR-induced cytotoxicity observed in FLC4 cells cultured on micro-space cell culture plates.
著者
Nathalie TOUBLANC Brigitte D LACROIX Junichi YAMAMOTO
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
pp.DMPK-13-RG-045, (Released:2013-07-23)
参考文献数
32
被引用文献数
20

Levetiracetam [E Keppra®] is a second generation antiepileptic drug for different types of epilepsy in adults and children ≥1 month. The objective is to develop a population pharmacokinetic model to describe the pharmacokinetics of levetiracetam in Japanese children and adults as well as North American children, the purpose being to explore potential dosing recommendations in Japanese children. Levetiracetam plasma concentration-time data were obtained from Japanese adult and paediatric clinical studies. The data were analysed through non-linear mixed effects modelling. The model was used to perform simulations and compare the exposure in Japanese children and adults. It was subsequently extended to North American children through an external validation. A one-compartment model with first-order absorption and first-order elimination adequately described the data. The exposure parameters determined based on the simulations in children were well within the adult range. The external validation against historical data from North American children was successful. The integrated population pharmacokinetic model provided a good description of the data, confirming the similarity of levetiracetam pharmacokinetics in these various populations. In Japanese children, a target dose of 10 to 30 mg/kg twice daily ensures the same exposure as the recommended dose in Japanese adults of 500 to 1500 mg twice daily.
著者
Kaoru KOBAYASHI Akane YOSHIDA Yoko EJIRI Sachiko TAKAGI Hanaka MIMURA Masaya HOSODA Tomokazu MATSUURA Kan CHIBA
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.27, no.5, pp.478-485, 2012 (Released:2012-10-26)
参考文献数
21
被引用文献数
18

Human hepatocellular carcinoma cell lines cultured in a monolayer show negligible activities of drug-metabolizing enzymes such as cytochrome P450s (CYPs) and UDP-glucuronosyltransferases (UGTs). Here, we show that culture of human hepatocellular carcinoma FLC-4 cells on 24-well plates arrayed with uniform micro-sized compartments on the bottom of the plates (micro-space cell culture plates) resulted in increased expression of drug-metabolizing enzymes (CYP1A2, CYP2C9, CYP3A4, UGT1A1, etc.) and nuclear receptors (pregnane X receptor, constitutive androstane receptor, etc.). When cells were treated with a typical CYP3A substrate (triazolam), CYP2C9 substrate (diclofenac) or UGT1A1 substrate (SN-38), large amounts of their metabolites were detected in the medium of cells cultured on micro-space cell culture plates. The formation of metabolites from triazolam, diclofenac and SN-38 was strongly inhibited by co-treatment with a CYP3A inhibitor (ketoconazole), CYP2C9 inhibitor (sulfaphenazole) and UGT1A1 inhibitor (ketoconazole), respectively. On the other hand, formation of metabolites was not observed in the medium of cells cultured in a monolayer. Finally, the cytotoxic effect of aflatoxin B1 was more potent in cells cultured on micro-space cell culture plates than in cells cultured in a monolayer. The results suggest that FLC-4 cells cultured on micro-space cell culture plates are useful for studying drug metabolism and drug-induced hepatotoxicity.
著者
Shinya Endo Yasuyuki Toyoda Tatsuki Fukami Miki Nakajima Tsuyoshi Yokoi
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
pp.DMPK-12-RG-019, (Released:2012-06-12)
参考文献数
44
被引用文献数
14

Drug-induced liver injury (DILI) is thought to be involved in the participation of drugs that either directly affect the cell viability or elicit an immune response. However, there is limited information about the immune responses induced by drugs, including those drugs that are metabolically activated. In this study, we constructed an in vitro assay system to assess the involvement of immune-related factors induced by metabolic activation of drugs. To investigate whether CYP3A4-mediated metabolism of 10 hepatotoxic drugs are associated with immune-related responses, human monocytic leukemia THP-1 cells were co-incubated with CYP3A4 Supersomes. Cluster of differentiation (CD) 86 and CD54 expression levels on THP-1 cells were upregulated by treatment with albendazole and amiodarone (AMD), respectively, in the presence of CYP3A4. Additionally, N-desethylamiodarone (DEA), a major metabolite of AMD, upregulated the CD54 expression of THP-1 cells with CYP3A4. The release of interleukin (IL) -8 and tumor necrosis factor (TNF) α from THP-1 cells was significantly increased by the treatment of AMD or DEA with CYP3A4. Similarly, IL-8 and TNFα were also upregulated by the treatment of AMD and DEA with human liver microsomes, but were inhibited by adding ketoconazole to the cell culture. In this study, we first report that albendazole, AMD and DEA activate immune reaction when metabolically activated.
著者
Hiroyuki TSUDA Yutaka OHSHIMA Hiroshi NOMOTO Ken-ichi FUJITA Eiji MATSUDA Masaaki IIGO Nobuo TAKASUKA Malcolm A. MOORE
出版者
日本薬物動態学会 会長/日本薬物動態学会 DMPK編集委員長
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.19, no.4, pp.245-263, 2004 (Released:2004-09-29)
参考文献数
152
被引用文献数
132 154

Increasing attention is being paid to the possibility of applying cancer chemopreventive agents for individuals at high risk of neoplastic development. For this purpose by natural compounds have practical advantages with regard to availability, suitability for oral application, regulatory approval and mechanisms of action. Candidate substances such as phytochemicals present in foods and their derivatives have been identified by a combination of epidemiological and experimental studies. Plant constituents include vitamin derivatives, phenolic and flavonoid agents, organic sulfur compounds, isothiocyanates, curcumins, fatty acids and d-limonene. Examples of compounds from animals are unsaturated fatty acids and lactoferrin. Recent studies have indicated that mechanisms underlying chemopreventive potential may be combinations of anti-oxidant, anti-inflammatory, immune-enhancing, and anti-hormone effects, with modification of drug-metabolizing enzymes, influence on the cell cycle and cell differentiation, induction of apoptosis and suppression of proliferation and angiogenesis playing roles in the initiation and secondary modification stages of neoplastic development. Accordingly, natural agents are advantageous for application to humans because of their combined mild mechanism. Here we review naturally occurring compounds useful for cancer chemprevention based on in vivo studies with reference to their structures, sources and mechanisms of action.
著者
Stephen CURRY
出版者
The Japanese Society for the Study of Xenobiotics
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.24, no.4, pp.342-357, 2009 (Released:2009-09-10)
参考文献数
100
被引用文献数
237 92

Human serum albumin (HSA) is an abundant and highly soluble plasma protein with the capacity to bind a remarkably diverse set of lipophilic anionic compounds so that it fulfils important roles in the transport of nutrients, hormones and toxins. The protein attracts great interest from the pharmaceutical industry since it can also bind a variety of drug molecules, impacting their delivery and efficacy. Our understanding of the binding and transport properties of albumin has been transformed by structural studies of the protein, in which crystallographic analysis has played a leading role. This review summarises the main insights to have accrued from this work, highlighting the significant advances that have been made but also pointing out some of the challenges ahead. Since further progress is likely to benefit from increased structural scrutiny of HSA, methodological developments instrumental to the success of crystallographic analysis of the protein are discussed in some detail.
著者
Yune-Fang UENG Ching-Chin TSAI Wei-Sheng LO Chul-Ho YUN
出版者
The Japanese Society for the Study of Xenobiotics
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.25, no.6, pp.560-567, 2010 (Released:2011-01-14)
参考文献数
40
被引用文献数
13

The roots of Sophora flavescens (Sf) have been widely used as a herbal medicine for the treatment of diarrhea, gastrointestinal hemorrhage, and eczema. Cytochrome P450 (P450) forms including CYP1A2, CYP2B, CYP2E1, and CYP3A participate in the oxidative metabolism of theophylline, which is an important bronchodilation agent with a narrow therapeutic index. To assess the interaction of Sf with theophylline, the effects of Sf extract on theophylline-metabolizing P450s and on the pharmacokinetic profile of theophylline were investigated in male Sprague-Dawley rats. Oral treatment of rats with the Sf extract caused dose-dependent increases of liver microsomal oxidation activities toward 7-ethoxyresorufin, 7-pentoxyresorufin, and nifedipine. However, nitrosodimethylamine N-demethylation activity was not affected. The ingestion of Sf extract stimulated theophylline 8-oxidation and N-demethylation activities. The increases of oxidative activities were in consensus with the elevation of the protein levels of CYP1A2, CYP2B1/2, CYP2C11, and CYP3A. Sf-treatment increased the clearance of theophylline and decreased the area under the concentration-time curve (AUC) and the area under the moment curve (AUMC). These results demonstrate that Sf reduces blood theophylline concentration through facilitating the elimination of theophylline. In patients taking Sf, possible P450 induction-induced drug interaction should be noted to decrease the risk of therapeutic failure or adverse effects resulting from the use of additional therapeutic agents.
著者
Thomas A. BAILLIE Allan E. RETTIE
出版者
The Japanese Society for the Study of Xenobiotics
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.26, no.1, pp.15-29, 2011 (Released:2011-03-03)
参考文献数
91
被引用文献数
111

It is now widely appreciated that drug metabolites, in addition to the parent drugs themselves, can mediate the serious adverse effects exhibited by some new therapeutic agents, and as a result, there has been heightened interest in the field of drug metabolism from researchers in academia, the pharmaceutical industry, and regulatory agencies. Much progress has been made in recent years in understanding mechanisms of toxicities caused by drug metabolites, and in understanding the numerous factors that influence individual exposure to products of drug biotransformation. This review addresses some of these factors, including the role of drug-drug interactions, reactive metabolite formation, individual susceptibility, and species differences in drug disposition caused by genetic polymorphisms in drug-metabolizing enzymes. Examples are provided of adverse reactions that are linked to drug metabolism, and the mechanisms underlying variability in toxic response are discussed. Finally, some future directions for research in this field are highlighted in the context of the discovery and development of new therapeutic agents.