著者

Takeshi AKIYOSHI Marie ITO Saori MURASE Mitsue MIYAZAKI F. Peter GUENGERICH Katsunori NAKAMURA Koujirou YAMAMOTO Hisakazu OHTANI

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.5, pp.411-415, 2013 (Released:2013-10-25)

参考文献数

31

被引用文献数

21

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Inhibition of cytochrome P450 (CYP) 3A4 is the major cause of drug-drug interactions (DDI). We have previously reported that the genetic variation of CYP3A4 significantly affected the inhibitory profiles of typical competitive inhibitors. In addition to competitive inhibition, some clinically significant DDI are attributable to mechanism-based inhibition (MBI). However, the differences in the MBI kinetics among CYP3A4 genetic variants remain to be characterized. In this study, we quantitatively investigated the inhibition kinetics of MBI inhibitors, erythromycin and clarithromycin, on the CYP3A4 variants CYP3A4.1, 4.2, 4.7, 4.16, and 4.18. The activity of CYP3A4 was assessed using testosterone 6β-hydroxylation with recombinant CYP3A4. Both erythromycin and clarithromycin decreased the activity of CYP3A4 in a time-dependent manner. The maximum inactivation rate constants, kinact,max, of erythromycin for CYP3A4.2 and CYP3A4.7 were 0.5-fold that for CYP3A4.1, while that for CYP3A4.16 and CYP3A4.18 were similar to that for CYP3A4.1. The KI values of erythromycin for CYP3A4.2, 4.7, 4.16, and 4.18 were 1.2-, 0.4-, 2.2- and 0.72-fold those of CYP3A4.1, respectively. Similar results were obtained for clarithromycin. In conclusion, the inhibitory profiles of MBI inhibitors, as well as competitive inhibitors, may possibly differ among CYP3A4 variants. This difference may contribute to interindividual differences in the extent of DDI based on MBI.

著者

Kiyoshi FUKUHARA Akiko OHNO Yosuke ANDO Takashi YAMOTO Haruhiro OKUDA

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.26, no.4, pp.399-406, 2011 (Released:2011-09-02)

参考文献数

23

被引用文献数

18

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The widely used analgesic-antipyretic drug acetaminophen (APAP) is known to cause serious liver necrosis at high doses in man and experimental animals. For studies of toxic processes, 1H NMR spectroscopy of biofluids allows monitoring of endogenous metabolite profiles that alter characteristically in response to changes in physiological status. Herein, a 1H NMR metabolomics approach was applied to the investigation of APAP toxicity in rats and the effect of phenobarbital (PB) on APAP-induced hepatotoxicity. Metabolite differences due to hepatotoxicity were observed in 1H NMR spectra of serum and urine, and enhanced APAP hepatotoxicity by pretreatment with PB was clearly shown by a principal components analysis of the spectral data. NMR spectra of APAP-dosed rat urine provided profiles of APAP-related compounds together with endogenous metabolites. By comparison of endogenous and APAP-related metabolite spectra with those from rats pretreated with PB, it was possible to show the importance of oxidative metabolism of APAP to N-acetyl-p-benzoquinone, an essential step in APAP hepatotoxicity.

著者

David C. GAZE

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.24, no.4, pp.333-341, 2009 (Released:2009-09-10)

参考文献数

70

被引用文献数

84

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The diagnosis of cardiac ischemia remains a challenge in contemporary emergency medicine. A blood-borne biomarker is an attractive alternative to cardiac imaging or stress testing as it would be cheaper and logistically faster to obtain. A number of candidate biomarkers have been proposed for the detection of cardiac ischemia; however, only Ischemia Modified Albumin (IMA) has been released for clinical use. IMA is a good discriminator between ischemic and non-ischemic patients. Changes in IMA concentration have shown to occur during coronary angioplasty-induced ischemia. Clinical studies indicate that IMA appears to offer on admission an early test which can be combined with electrocardiographic findings and cardiac troponin measurements for the early exclusion of acute coronary syndrome. IMA is an independent predictor of short and long term adverse outcomes in patients with acute chest pain. However, this test is relatively new and uncertainties remain. Elevations of IMA occur in conditions other than chest pain, thus questioning its specificity. The mechanism of IMA formation and the precise entity being measured are not fully known. Nevertheless, IMA measurement remains the only current clinical biomarker which may be used for the diagnosis of patients suspected of cardiac ischemia.

著者

Kyoko FUKUMOTO Takashi KOBAYASHI Kazuo KOMAMURA Shiro KAMAKURA Masafumi KITAKAZE Kazuyuki UENO

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.20, no.6, pp.423-427, 2005 (Released:2006-01-11)

参考文献数

30

被引用文献数

13 11

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We investigated whether there was a stereoselective effect of amiodarone on the pharmacokinetics of carvedilol. Among a series of 106 inpatients with heart failure, 52 received carvedilol monotherapy (carvedilol group) and 54 received carvedilol plus amiodarone (carvedilol+amiodarone group). The serum carvedilol concentration administered/dose ratio was compared between the two groups based on HPLC measurement of the serum levels of carvedilol, amiodarone, and desethylamiodarone. In 6 patients from the carvedilol group, serum carvedilol levels were compared before and after coadministration of amiodarone. There was no significant between-group difference of the serum concentration to dose (C/D ratio) for the R-enantiomer carvedilol, however, the C/D ratio for the S-enantiomer and the serum S-carvedilol to R-carvedilol (S/R) ratio were both significantly lower in the carvedilol group than in the carvedilol+amiodarone group(47.8±56.7 versus 95.3±105 ng/mg/kg, P=0.0048 and 0.460±0.207 versus 0.879±0.377 ng/mg/kg, P<0.001), respectively. Furthermore, the mean S-carvedilol concentration over 14 days of coadministration with amiodarone was higher than that before coadministration (6.54±1.73 ng/mL versus 3.03±0.670 ng/mL, P<0.001). These results suggest that metabolism of S-carvedilol was markedly inhibited by coadministration of amiodarone.

著者

Yuki Kondo Sachimi Yoshihashi Kayo Mimori Ruri Ogihara Yoshinori Kanehama Yoshiyuki Maki Shin Enosawa Kouichi Kurose Takahiro Iwao Katsunori Nakamura Tamihide Matsunaga

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-14-RG-022, (Released:2014-04-29)

参考文献数

22

被引用文献数

9

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This study aimed to establish culture conditions which are able to give the differentiation of induced pluripotent (iPS) cells to the hepatocytes. To this end, we examined the usefulness of culture medium containing the components involved in the intermediary metabolism in the liver. More specifically, we examined the effect of the 'modified L-15 medium' containing galactose, phenylalanine and ornitine, but deprived of glucose, tyrosine, arginine and pyruvic acid. The medium was altered according to changes in the expression of enzymes that participate in liver-specific pathways. After 25 days of differentiation, the differentiated cells expressed hepatocyte markers and drug-metabolizing enzymes. These expression levels were increased using modified L-15 medium. The survival of human fetal liver cells and the death of human fibroblasts were observed during culture in modified L-15 medium. Most of the cells that differentiated from human iPS cells using modified L-15 medium were stained by anti-human albumin antibody. These results suggest that iPS cells can be converted to high purity-differentiated hepatocytes by cultivating them in modified L-15 medium.

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

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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

Ikumi TAMAI

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.6, pp.451-452, 2013 (Released:2013-12-25)

参考文献数

13

被引用文献数

1

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

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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

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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

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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

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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

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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.