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1.
Transplant Cell Ther ; 30(1): 105.e1-105.e10, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37806448

ABSTRACT

Juvenile myelomonocytic leukemia (JMML), which is classified as a myelodysplastic/myeloproliferative neoplasm, is a rare hematologic malignancy of childhood. Most patients with JMML require allogeneic hematopoietic cell transplantation (HCT) as a curative therapy. A Japanese retrospective analysis demonstrated favorable outcomes for a busulfan (BU) + fludarabine (FLU) + melphalan (MEL) regimen, with an overall survival (OS) of 72% and an event-free survival (EFS) of 53%. To further validate the efficacy and safety of this regimen, the Japan Pediatric Leukemia/Lymphoma Study Group (JPLSG) conducted a nationwide prospective study, JMML-11. Between July 2011 and June 2017, 28 patients with newly diagnosed JMML were enrolled in JMML11. Low-dose chemotherapy for tumor control before HCT was recommended, and patients treated with AML-type chemotherapy and azacitidine were excluded. The conditioning regimen comprised i.v. BU, 16 doses administered every 6 h, with dose adjustment based on pharmacokinetic (PK) studies on days -11 to -8; FLU, 30 mg/m2/day or 1 mg/kg/day for patients <10 kg or age <1 year on days -7 to -4; and MEL, 90 mg/m2/day or 3 mg/kg/day for patients <10 kg or <1 year on days -3 to -2. The donor was selected by the physician in charge. A family donor was available for 7 patients (3 HLA-matched siblings, 3 HLA-1-antigen mismatched parents, and 1 haploidentical father). Overall, 21 patients received grafts from unrelated donors, including 8 HLA-matched donors and 13 HLA-mismatched donors. The graft source was related bone marrow (BM) for 7 patients, unrelated BM for 14 patients, and unrelated cord blood for 7 patients. Neutrophil engraftment was achieved in 21 of 28 patients (75%), with a median of 20.5 days (range, 11 to 39 days) after transplantation. The 3-year OS, 3-year EFS, 3-year relapse rate, and 3-year transplantation-related mortality were 63% (95% confidence interval [CI], 42% to 78%), 52% (95% CI, 32% to 69%), 18% (95% CI, 6% to 34%), and 21% (95% CI, 9% to 38%), respectively. WBC count before the conditioning regimen (≥7.0 × 109/L) was significantly associated with inferior EFS and OS. Body surface area ≥.5 m2, spleen size <4 cm before conditioning, and HLA-matched unrelated BM donors were significantly associated with better OS. Adverse effects related to the conditioning regimen included febrile neutropenia (86%), diarrhea (39%), hypoxemia (21%), and mucositis (18%). BU-associated toxicity, including sinusoidal obstruction syndrome (SOS) and thrombotic microangiopathy (TMA), occurred in 7 patients (25%; SOS, n = 6; TMA, n = 2). Retrospective analysis of PK data after the first BU dose in 23 patients, including 6 with SOS and 17 without SOS, did not show significant differences between groups. The JMML-11 study confirms the positive results of previous retrospective analyses. BU+FLU+MEL might become a standard conditioning regimen for patients with JMML.


Subject(s)
Hematopoietic Stem Cell Transplantation , Leukemia, Myelomonocytic, Juvenile , Lymphoma , Child , Humans , Busulfan/therapeutic use , Hematopoietic Stem Cell Transplantation/adverse effects , Japan , Leukemia, Myelomonocytic, Juvenile/drug therapy , Leukemia, Myelomonocytic, Juvenile/complications , Lymphoma/complications , Lymphoma/drug therapy , Melphalan/therapeutic use , Prospective Studies , Retrospective Studies , Transplantation, Homologous
2.
Blood Adv ; 5(19): 3891-3899, 2021 10 12.
Article in English | MEDLINE | ID: mdl-34500465

ABSTRACT

The role of allogeneic hematopoietic stem cell transplantation (HSCT) for infants with acute lymphoblastic leukemia (ALL) and KMT2A gene rearrangement (KMT2A-r) is controversial in terms of both its efficacy and potential for acute and late toxicities. In Japanese Pediatric Leukemia/Lymphoma Study Group trial MLL-10, by introducing intensive chemotherapy, indication of HSCT was restricted to patients with high-risk (HR) features only (KMT2A-r and either age <180 days or presence of central nervous system leukemia). Of the 56 HR patients, 49 achieved complete remission. Forty-three patients received HSCT in first remission including 38 patients receiving protocol-specified HSCT with conditioning consisting of individualized targeted doses of busulfan, etoposide, and cyclophosphamide. Three-year event-free survival (EFS) of 56.8% (95% confidence interval [CI], 42.4% to 68.8%) and overall survival of 80.2% (95% CI, 67.1% to 88.5%) were accomplished. Univariable analysis showed that Interfant-HR criteria and flow cytometric minimal residual disease (MRD; ≥0.01%), both at the end of induction and at the end of consolidation (EOC), were significantly associated with poorer EFS. In the multivariable analysis, positive MRD at EOC was solely associated with poor EFS (P < .001). Rapid pretransplant MRD clearance and tailored HSCT strategy in the MLL-10 trial resulted in a favorable outcome for infants with HR KMT2A-r ALL. However, considering the high rate of potentially life-threatening toxicities and the risk of late effects, its indication should be further restricted or even eliminated in the future by introducing more effective therapeutic modalities with minimal toxicities. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.


Subject(s)
Hematopoietic Stem Cell Transplantation , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Histone-Lysine N-Methyltransferase/genetics , Humans , Myeloid-Lymphoid Leukemia Protein/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Prognosis
3.
Drug Metab Pharmacokinet ; 36: 100364, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33341662

ABSTRACT

The inhibition of CYP2C9-mediated warfarin metabolism by acid or lactone forms of statin converted in the body and effects of CYP2C9 genetic variants on their inhibition are not fully understood. Here, the effects of acid and lactone forms of statins on S-warfarin 7-hydroxylation were investigated in vitro. S-Warfarin 7-hydroxylase activities of human liver microsomes (HLMs), recombinant CYP2C9.1 (rCYP2C9.1), and rCYP2C9.3 (Ile359Leu variant) in the presence of statins were determined by high-performance liquid chromatography. Lactone forms of atorvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin, and simvastatin inhibited the activity of HLMs more potently than the corresponding acid forms, whereas fluvastatin acid showed stronger inhibition than fluvastatin lactone. When the effects of statins on rCYP2C9 variants were examined, inhibition profiles of acid versus lactone forms of statins except for fluvastatin were similar between rCYP2C9.1 and rCYP2C9.3. However, the degrees of inhibition by atorvastatin lactone, fluvastatin acid, fluvastatin lactone, lovastatin lactone, and pitavastatin lactone (Ki values) were significantly different between these variants. These results indicated that lactone forms of statins other than fluvastatin showed more potent inhibition of CYP2C9-catalyzed S-warfarin 7-hydroxylation than the corresponding acid forms. Furthermore, our results indicated that Ile359Leu substitution in CYP2C9 affected the inhibitory potencies of statins.


Subject(s)
Cytochrome P-450 CYP2C9/genetics , Cytochrome P-450 CYP2C9/metabolism , Hydroxymethylglutaryl-CoA Reductase Inhibitors/metabolism , Microsomes, Liver/metabolism , Pharmacogenomic Variants/physiology , Warfarin/metabolism , Acids/metabolism , Catalysis , Dose-Response Relationship, Drug , Drug Interactions/physiology , Female , Humans , Hydroxylation/physiology , Hydroxymethylglutaryl-CoA Reductase Inhibitors/chemistry , Lactones/metabolism , Male , Microsomes, Liver/drug effects , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Warfarin/pharmacology
4.
Blood ; 136(16): 1813-1823, 2020 10 15.
Article in English | MEDLINE | ID: mdl-32845001

ABSTRACT

The prognosis for infants with acute lymphoblastic leukemia (ALL), particularly those with KMT2A gene rearrangement (KMT2A-r), is dismal. Continuous efforts have been made in Japan to investigate the role of hematopoietic stem cell transplantation (HSCT) for infants with KMT2A-r ALL, but improvement in outcome was modest. In the Japanese Pediatric Leukemia/Lymphoma Study Group MLL-10 trial, infants with ALL were stratified into 3 risk groups (low risk [LR], intermediate risk [IR], and high risk [HR]) according to KMT2A status, age, and presence of central nervous system leukemia. Children's Oncology Group AALL0631 modified chemotherapy with the addition of high-dose cytarabine in early intensification was introduced to KMT2A-r patients, and the option of HSCT was restricted to HR patients only. The role of minimal residual disease (MRD) was also evaluated. Ninety eligible infants were stratified into LR (n = 15), IR (n = 19), or HR (n = 56) risk groups. The 3-year event-free survival (EFS) rate for patients with KMT2A-r ALL (IR + HR) was 66.2% (standard error [SE], 5.6%), and for those with germline KMT2A (KMT2A-g) ALL (LR), the 3-year EFS rate was 93.3% (SE, 6.4%). The 3-year EFS rate was 94.4% (SE, 5.4%) for IR patients and 56.6% (SE, 6.8%) for HR patients. In multivariable analysis, female sex and MRD ≥0.01% at the end of early consolidation were significant factors for poor prognosis. Risk stratification and introduction of intensive chemotherapy in this study were effective and were able to eliminate HSCT for a subset of infants with KMT2A-r ALL. Early clearance of MRD seems to have translated into favorable outcomes and should be incorporated into risk stratifications in future trials. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.


Subject(s)
Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/therapy , Age Factors , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Clinical Decision-Making , Clinical Trials as Topic , Disease Management , Female , Hematopoietic Stem Cell Transplantation , Humans , Infant , Japan , Male , Multicenter Studies as Topic , Neoplasm, Residual , Precursor Cell Lymphoblastic Leukemia-Lymphoma/etiology , Prognosis , Treatment Outcome
5.
Life Sci ; 258: 118140, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32730838

ABSTRACT

AIMS: This study was performed to investigate the expression profile of cytochrome P450 (CYP) isoforms and effects of polycyclic aromatic hydrocarbons (PAHs) and antiepileptic drugs on CYP1 expression in human astrocytoma MOG-G-CCM cells. MAIN METHODS: CYP1A1 and CYP1B1 expression were determined by quantitative real-time polymerase chain reaction, Western blotting, and immunocytochemistry. KEY FINDINGS: MOG-G-CCM cells expressed various CYP isoforms. Among the CYP isoforms analyzed, CYP1B1 showed the highest expression level, followed by CYP1A1. Furthermore, CYP1B1 was localized in both the endoplasmic reticulum and mitochondria. 3-Methylcholanthrene (3-MC), benz[a]anthracene (B[a]A), benzo[a]pyrene (B[a]P), and valproic acid (VPA) increased the expression of CYP1B1 and CYP1A1. The potent aryl hydrocarbon receptor antagonist GNF351 significantly suppressed the 3-MC- and VPA-mediated upregulation of CYP1B1 and CYP1A1. In addition, VPA potentiated the induction of CYP1B1 and CYP1A1 by 3-MC, B[a]A, and B[a]P, although the augmentation of CYP1A1 was more remarkable than that of CYP1B1. In contrast, other antiepileptic drugs (carbamazepine, lamotrigine, levetiracetam, phenytoin) did not affect the 3-MC-mediated upregulation of CYP1B1 and CYP1A1. VPA is known to act as a histone deacetylase (HDAC) inhibitor. Therefore, the effects of trichostatin A, a representative HDAC inhibitor, on CYP1 induction by 3-MC were examined. Trichostatin A enhanced the 3-MC-mediated upregulation of CYP1A1 but not CYP1B1. SIGNIFICANCE: These results partially indicated that VPA may augment the PAH-mediated induction of CYP1B1 and CYP1A1 through the activation of transcription by HDAC inhibition.


Subject(s)
Anticonvulsants/pharmacology , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP1B1/genetics , Polycyclic Aromatic Hydrocarbons/pharmacology , Up-Regulation/drug effects , Valproic Acid/pharmacology , Astrocytes/drug effects , Astrocytes/metabolism , Cell Line, Tumor , Humans , Transcriptome/drug effects
6.
Biol Pharm Bull ; 43(4): 688-692, 2020.
Article in English | MEDLINE | ID: mdl-32238710

ABSTRACT

Sesamin is a major lignan in sesame seeds, and a recent meta-analysis of controlled trials indicated that sesamin intake decreases blood pressure. The antihypertensive effect of sesamin has been suggested to be due to sesamin-mediated suppression of 20-hydroxyeicosatetraenoic acid production catalyzed by CYP4F2. However, the detailed mechanism underlying inhibition of CYP4F2 function by sesamin remains unclear. In this study, the effects of sesamin on catalytic activity of CYP4F2 were investigated in vitro. Sesamin inhibited luciferin-4F2/3 O-dealkylase activity of recombinant human CYP4F2 with an IC50 value of 0.381 µM. When preincubated in the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH) for 20 min, sesamin potentiated the inhibition of CYP4F2 activity. Moreover, kinetic analysis of the inactivation revealed that sesamin showed a preincubation time- and concentration-dependent inhibition of CYP4F2 activity yielding a maximal inactivation rate constant (kinact) value of 0.354 min-1 and half-maximal inhibitory concentration (KI) value of 1.12 µM. The inactivation of CYP4F2 by sesamin required NADPH. These results indicated that sesamin is a mechanism-based inactivator of human CYP4F2.


Subject(s)
Cytochrome P450 Family 4/antagonists & inhibitors , Dioxoles/pharmacology , Lignans/pharmacology , Animals , Baculoviridae , Cytochrome P450 Family 4/genetics , Cytochrome P450 Family 4/metabolism , Insecta , Microsomes/metabolism , NADP/metabolism , Recombinant Proteins/metabolism
7.
Gan To Kagaku Ryoho ; 46(5): 961-963, 2019 May.
Article in Japanese | MEDLINE | ID: mdl-31189826

ABSTRACT

We encountered 2 cases of T790M-positive non-small cell lung cancer in patients who developed toxic erythema within a week after initiation of osimertinib(80mg/day)therapy. Since osimertinib was regarded as the suspected drug, we adminis- tered desensitization therapy for osimertinib at an initial dose of 10mg/day. During the process of dose escalation, slight eruption and flare were observed, but we were able to provide appropriate treatment. Osimertinib therapy was continued and conferred tumor reduction in both cases. We report the clinical course and suggest that desensitization therapy is an alternative therapy for patients who present with drug-induced allergic reaction.


Subject(s)
Acrylamides/adverse effects , Aniline Compounds/adverse effects , Carcinoma, Non-Small-Cell Lung , Erythema/chemically induced , Lung Neoplasms , Antineoplastic Agents , Carcinoma, Non-Small-Cell Lung/drug therapy , ErbB Receptors , Humans , Lung Neoplasms/drug therapy , Mutation , Protein Kinase Inhibitors
8.
Chem Biol Interact ; 306: 1-9, 2019 Jun 01.
Article in English | MEDLINE | ID: mdl-30965050

ABSTRACT

The inhibitory effects of antihypertensive drugs (dihydropyridine calcium channel blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors) on cytochrome P450 2J2 (CYP2J2) activity were examined. Amlodipine, azelnidipine, barnidipine, benidipine, cilnidipine, efonidipine, felodipine, manidipine, nicardipine, nifedipine, nilvadipine, nisoldipine, nitrendipine, telmisartan, delapril, and quinapril inhibited luciferin-2J2/4F12 O-dealkylase activity of recombinant human CYP2J2 in a concentration-dependent manner (IC50 = 0.116-9.19 µM). Kinetic analyses of the inhibition indicated that azelnidipine, barnidipine, benidipine, cilnidipine, efonidipine, manidipine, nicardipine, telmisartan, delapril, and quinapril competitively inhibited CYP2J2 activity, while amlodipine, felodipine, nifedipine, nilvadipine, nisoldipine, and nitrendipine showed mixed inhibition. Among these drugs, manidipine showed the strongest reversible inhibition with Ki value of 0.0294 µM. The docking simulation data supported the potent inhibition of CYP2J2 by these drugs. Next, the effect of preincubation on CYP2J2 inhibition was investigated to determine whether these antihypertensive drugs inhibited CYP2J2 activity in a metabolism-dependent manner. A 20-min preincubation of azelnidipine and felodipine in the presence of NADPH potentiated the inhibition of CYP2J2. Furthermore, kinetic analysis of the inactivation showed that azelnidipine caused a preincubation time- and concentration-dependent decrease in CYP2J2 activity yielding kinact/KI value of 105 l/mmol/min, although felodipine showed no preincubation time-dependent inhibition. The azelnidipine-mediated inactivation required NADPH. These results indicated that manidipine is a potent competitive reversible inhibitor while azelnidipine is a potent mechanism-based inactivator of human CYP2J2.


Subject(s)
Antihypertensive Agents/pharmacology , Azetidinecarboxylic Acid/analogs & derivatives , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Cytochrome P-450 Enzyme System/metabolism , Dihydropyridines/pharmacology , Animals , Antihypertensive Agents/chemistry , Azetidinecarboxylic Acid/chemistry , Azetidinecarboxylic Acid/pharmacology , Cytochrome P-450 CYP2J2 , Cytochrome P-450 Enzyme Inhibitors/chemistry , Dihydropyridines/chemistry , Dose-Response Relationship, Drug , Humans , Molecular Docking Simulation , Nitrobenzenes , Piperazines , Recombinant Proteins/metabolism , Structure-Activity Relationship
9.
J Clin Pharm Ther ; 44(4): 565-571, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30950099

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: Azole antifungal drugs are often co-administered with tacrolimus after allogeneic hematopoietic stem cell transplantation (HSCT). However, the influence of azole antifungal drugs on variation in tacrolimus pharmacokinetics when switching from intravenous tacrolimus (Tac-iv) to once-daily modified release tacrolimus (Tac-MR) remains to be elucidated. This study was performed to evaluate the effects of oral azole antifungal drugs on variation in tacrolimus pharmacokinetics after conversion to Tac-MR in HSCT patients. METHODS: Patients concomitantly receiving fluconazole (FLCZ) or voriconazole (VRCZ) along with tacrolimus were evaluated retrospectively. Blood tacrolimus concentrations before and after changing to oral administration were compared between FLCZ and VRCZ groups. RESULTS AND DISCUSSION: A total of 52 patients (34 FLCZ and 18 VRCZ) were included in the analysis. There were no significant differences in the most recent daily dose (Div ) and blood level (Civ ) of Tac-iv, Civ /Div , and ratio of daily dose of tacrolimus on the first to second day after changing to Tac-MR (Dpo1-2 ) to Div between FLCZ and VRCZ groups (P > 0.2). The trough levels of tacrolimus on the first to second day after switching to Tac-MR (Cpo1-2 ) and on the third to fifth day after the switch (Cpo3-5 ) were significantly higher in the VRCZ group than the FLCZ group (P < 0.05). The values of (Civ /Div )/(Cpo1-2 /Dpo1-2 ) and (Civ /Div )/(Cpo3-5 /Dpo3-5 ) in the VRCZ group were significantly lower compared with those in the FLCZ group (P < 0.05). Furthermore, individual values of (Civ /Div )/(Cpo3-5 /Dpo3-5 ) in the FLCZ group varied widely. WHAT IS NEW AND CONCLUSION: Voriconazole increased blood tacrolimus level more markedly than FLCZ after switching to Tac-MR, whereas FLCZ caused a large variation in tacrolimus blood level. These results suggest that therapeutic monitoring of tacrolimus after the switch may need to be performed carefully considering that orally co-administered VRCZ and FLCZ exhibit different change in blood tacrolimus level just after the switch.


Subject(s)
Antifungal Agents/therapeutic use , Azoles/therapeutic use , Tacrolimus/blood , Administration, Intravenous , Adult , Female , Fluconazole/therapeutic use , Hematopoietic Stem Cell Transplantation/methods , Humans , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/blood , Immunosuppressive Agents/pharmacokinetics , Male , Middle Aged , Retrospective Studies , Tacrolimus/administration & dosage , Tacrolimus/pharmacokinetics , Voriconazole/therapeutic use , Young Adult
10.
Hepatol Res ; 49(9): 1003-1014, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31026368

ABSTRACT

AIM: To evaluate the clinical and molecular characteristics of hepatitis E virus (HEV) infection in Mie Prefecture, Japan, from 2004 through 2018. METHODS: The clinical information of hepatitis E cases was collected from 21 medical institutions in Mie Prefecture. The nucleotide sequences of infecting HEV strains were determined for cases with available serum samples. The origins or transmission routes were inferred from phylogenetic analyses of the nucleotide sequences. RESULTS: Fifty-three patients were diagnosed with HEV infection. The number of cases increased each year through 2012 and then decreased. Analyses of the clinical characteristics of the cases indicated that even mild cases were detected in the latter 10 years of the study. Nucleotide sequence analyses were undertaken on 38 of the 53 cases. The HEV subtype 3e (HEV-3e) strains identified for 13 cases were closely related to a swine HEV-3e strain that was isolated from the liver of a pig bred in Mie Prefecture. The number of cases infected with the indigenous Mie HEV-3e strains increased until 2012 but have not been reported since 2014. In the latter half of the study, cases involving various HEV strains of different genotypes and subtypes emerged. CONCLUSIONS: The disappearance of indigenous Mie HEV-3e strains appeared to be the primary cause for the decrease in hepatitis E cases in Mie Prefecture. The disappearance might have been associated with improved hygienic conditions on pig farms or the closure of contaminated farms. The results suggest that indigenous HEV strains can be eradicated by appropriate management.

11.
J Pharmacol Exp Ther ; 366(3): 446-457, 2018 09.
Article in English | MEDLINE | ID: mdl-29976573

ABSTRACT

The specificity of cytochrome P450 4A11 (CYP4A11) against luciferin-4A O-demethylation in human liver microsomes (HLMs) and human renal microsomes (HRMs) and selectivity of CYP4A11 inhibition by epalrestat were investigated. Kinetic analysis of luciferin-4A O-demethylation yielded Vmax and S50 values of 39.7 pmol/min per milligram protein and 43.2 µM for HLMs (Hill coefficient 1.24) and 39.4 pmol/min per milligram protein and 33.8 µM for HRMs (Hill coefficient 1.34), respectively. Among the selective CYP inhibitors tested, HET0016 (CYP4 inhibitor) exclusively inhibited luciferin-4A O-demethylation by HLMs and HRMs. Furthermore, anti-CYP4A11 antibody nearly abolished the activity of both tissue microsomes. Luciferin-4A O-demethylase activity of HLMs was significantly correlated with lauric acid ω-hydroxylase activity, a marker of CYP4A11 activity (r = 0.904, P < 0.0001). Next, effects of epalrestat on CYP-mediated drug oxidations were examined. Epalrestat showed the most potent inhibition against CYP4A11 (IC50 = 1.82 µM) among the 17 recombinant enzymes tested. The inhibitory effect of epalrestat on CYP4A11 was at least 10-fold stronger than those on CYP4F2, CYP4F3B, and CYP4F12. For known CYP4 inhibitors, in contrast, HET0016 inhibited the activities of CYP4A11 and CYP4F2 (IC50 = 0.0137-0.0182 µM); 17-octadecynoic acid reduced activities of CYP4A11, CYP4F2, CYP4F3B, and CYP4F12 to a similar extent (IC50 = 5.70-17.7 µM). Epalrestat selectively and effectively inhibited the CYP4A11 activity of HLMs (IC50 = 0.913 µM) and HRMs (IC50 = 0.659 µM). These results indicated that luciferin-4A O-demethylase activity is a good CYP4A11 marker of HLMs and HRMs, and that epalrestat is a more selective CYP4A11 inhibitor compared with known CYP4 inhibitors.


Subject(s)
Cytochrome P-450 CYP4A/antagonists & inhibitors , Cytochrome P-450 CYP4A/metabolism , Cytochrome P-450 Enzyme Inhibitors/pharmacology , Microsomes/enzymology , Molecular Probes/metabolism , Quinolines/pharmacology , Rhodanine/analogs & derivatives , Thiazoles/pharmacology , Thiazolidines/pharmacology , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Kidney/cytology , Kinetics , Liver/cytology , Rhodanine/pharmacology
12.
Biol Pharm Bull ; 38(3): 441-7, 2015.
Article in English | MEDLINE | ID: mdl-25757926

ABSTRACT

Iguratimod is a novel disease-modifying antirheumatic drug. A blue letter (safety advisory) for drug interaction between iguratimod and warfarin was issued by the Ministry of Health, Labour and Welfare of Japan in May 2013. Iguratimod may affect warfarin metabolism catalyzed by CYP. However, it is not clear whether iguratimod inhibits warfarin oxidation. This study was performed to investigate the effects of iguratimod on warfarin 7-hydroxylation with human liver microsomes (HLMs) and recombinant CYP enzymes. Iguratimod concentration-dependently inhibited R,S-warfarin 7-hydroxylase activity of HLMs with an IC50 value of 15.2 µM. The inhibitory effect was examined with S-warfarin and R-warfarin to determine which enantiomer was more potently inhibited by iguratimod. Iguratimod potently inhibited the S-warfarin 7-hydroxylase activity of HLMs with an IC50 value of 14.1 µM, but showed only slight inhibition of R-warfarin 7-hydroxylation. Furthermore, iguratimod inhibited the S-warfarin 7-hydroxylase activity of recombinant CYP2C9.1 (rCYP2C9.1) and rCYP2C9.3 in a concentration-dependent manner with IC50 values of 10.8 and 20.1 µM, respectively. Kinetic analysis of the inhibition of S-warfarin 7-hydroxylation by iguratimod indicated competitive-type inhibition for HLMs and rCYP2C9.1 but mixed-type inhibition for rCYP2C9.3. The Ki values for HLMs, rCYP2C9.1, and rCYP2C9.3 were 6.74, 4.23, and 14.2 µM, respectively. Iguratimod did not exert metabolism-dependent inhibition of S-warfarin 7-hydroxylation. These results indicated that iguratimod is a potent direct inhibitor of CYP2C9-mediated warfarin 7-hydroxylation and that its inhibitory effect on CYP2C9.1 was more sensitive than that on CYP2C9.3.


Subject(s)
Chromones/pharmacology , Cytochrome P-450 CYP2C9/metabolism , Drug Interactions , Liver/drug effects , Sulfonamides/pharmacology , Warfarin/pharmacokinetics , Aged , Antirheumatic Agents/pharmacology , Humans , Hydroxylation , Immunosuppressive Agents/pharmacology , Inhibitory Concentration 50 , Kinetics , Liver/metabolism , Microsomes, Liver/drug effects , Microsomes, Liver/metabolism , Stereoisomerism , Warfarin/metabolism
14.
PLoS One ; 9(8): e104010, 2014.
Article in English | MEDLINE | ID: mdl-25084468

ABSTRACT

In this study, we aimed to elucidate the effects and mechanism of action of valproic acid on hepatic differentiation from human induced pluripotent stem cell-derived hepatic progenitor cells. Human induced pluripotent stem cells were differentiated into endodermal cells in the presence of activin A and then into hepatic progenitor cells using dimethyl sulfoxide. Hepatic progenitor cells were matured in the presence of hepatocyte growth factor, oncostatin M, and dexamethasone with valproic acid that was added during the maturation process. After 25 days of differentiation, cells expressed hepatic marker genes and drug-metabolizing enzymes and exhibited drug-metabolizing enzyme activities. These expression levels and activities were increased by treatment with valproic acid, the timing and duration of which were important parameters to promote differentiation from human induced pluripotent stem cell-derived hepatic progenitor cells into hepatocytes. Valproic acid inhibited histone deacetylase activity during differentiation of human induced pluripotent stem cells, and other histone deacetylase inhibitors also enhanced differentiation into hepatocytes. In conclusion, histone deacetylase inhibitors such as valproic acid can be used to promote hepatic differentiation from human induced pluripotent stem cell-derived hepatic progenitor cells.


Subject(s)
Cell Differentiation/drug effects , Hepatocytes/cytology , Histone Deacetylase Inhibitors/pharmacology , Induced Pluripotent Stem Cells/cytology , Valproic Acid/pharmacology , Adult , Aged , Albumins/metabolism , Biomarkers/metabolism , Cell Line , Cell Shape/drug effects , Cytochrome P-450 CYP3A/biosynthesis , Cytochrome P-450 CYP3A/genetics , Enzyme Induction/drug effects , Fluorescent Antibody Technique , Hepatocytes/drug effects , Humans , Inactivation, Metabolic/drug effects , Induced Pluripotent Stem Cells/drug effects , Induced Pluripotent Stem Cells/enzymology , Middle Aged , RNA, Messenger/genetics , RNA, Messenger/metabolism , Small Molecule Libraries/pharmacology , Staining and Labeling , Substrate Specificity/drug effects
16.
Drug Metab Pharmacokinet ; 29(3): 237-43, 2014.
Article in English | MEDLINE | ID: mdl-24334537

ABSTRACT

The use of human induced pluripotent stem (iPS) cells would be of great value for a variety of applications involving drug development studies. Several reports have been published on the differentiation of human iPS cells into hepatocyte-like cells; however, the cells were insufficient for application in drug metabolism studies. In this study, we aimed to establish effective methods for differentiation of human iPS cells into hepatocytes. Two human iPS cell lines were differentiated by addition of activin A, dimethyl sulfoxide, hepatocyte growth factor, oncostatin M, and dexamethasone. The differentiated cells expressed hepatocyte markers and drug-metabolizing enzymes, revealing that the human iPS cells were differentiated into hepatocyte-like cells. Expression of CYP3A4 and UGT1A1 mRNAs increased with treatment with typical inducers of the enzymes, and the response of the cells against the inducers was similar to that of human hepatocytes. Furthermore, the drug-metabolizing activity of CYP3A4, as monitored by testosterone 6ß-hydroxylase activity, was elevated by these inducers. In conclusion, we established methods for differentiation of hepatocyte-like cells expressing drug metabolizing activity from human iPS cells. The hepatocyte-like cells derived from human iPS cells will be useful for drug metabolism studies.


Subject(s)
Cell Differentiation/physiology , Hepatocytes/metabolism , Hepatocytes/physiology , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/physiology , Activins/metabolism , Cell Differentiation/genetics , Cell Line , Cytochrome P-450 CYP3A/genetics , Cytochrome P-450 CYP3A/metabolism , Dexamethasone/metabolism , Dimethyl Sulfoxide/metabolism , Glucuronosyltransferase/genetics , Glucuronosyltransferase/metabolism , Hepatocyte Growth Factor/metabolism , Humans , Inactivation, Metabolic/genetics , Inactivation, Metabolic/physiology , Oncostatin M/metabolism , RNA, Messenger/genetics , Steroid Hydroxylases/metabolism
17.
Hepatol Res ; 44(10): E63-E76, 2014 Oct.
Article in English | MEDLINE | ID: mdl-23927634

ABSTRACT

AIM: To characterize hepatitis E in Mie prefecture and to investigate whether raw pig liver sold as food in Mie is contaminated with hepatitis E virus (HEV) strains similar to those recovered from patients. METHODS: Seventeen patients with sporadic acute hepatitis E treated from 2004 to 2012 were studied. A total of 243 packages of raw pig liver from regional grocery stores were tested for the presence of HEV RNA. The partial genomic sequences of human and swine HEV isolates were determined and subjected to the phylogenetic analyses. RESULTS: The HEV isolates recovered from the 17 patients segregated into genotype 3 (n = 15) and genotype 4 (n = 2), and 15 genotype 3 isolates further segregated into 3e (n = 11) and 3b (n = 4). Pig liver specimens from 12 (4.9%) of the 243 packages had detectable HEV RNA. All 12 swine HEV isolates were grouped into genotype 3 (3a or 3b). Although no 3e strains were isolated from pig liver specimens, two 3b swine strains were 99.5-100% identical to two HEV strains recovered from hepatitis patients, within 412-nt partial sequences. CONCLUSION: The 3e HEV was prevalent among hepatitis E patients. HEV RNA was detected in approximately 5% of pig liver sold as food. The presence of identical HEV strains between hepatitis patients and pig liver indicated that pigs play an important role as reservoirs for HEV in humans in Mie. Further studies are needed to clarify the source of 3e HEV in the animal and environmental reservoirs.

18.
Drug Metab Pharmacokinet ; 28(3): 250-9, 2013.
Article in English | MEDLINE | ID: mdl-23291635

ABSTRACT

Human induced pluripotent stem cells (iPSCs) are a valuable source of hepatocytes for applications in drug metabolism studies. However, the current protocols for generating iPSC-derived hepatocyte-like cells (iPSHCs) are still very inefficient, and iPSHCs do not have sufficient hepatocyte-specific features, which include expression of a series of hepatocyte-specific genes, such as those encoding cytochrome P450 (CYP). In this study, we investigated whether introduction of human hepatocyte nuclear factor 6 (HNF6) could modulate the expression of CYP3A4 and other CYP genes in iPSHCs as well as in HepG2 cells, a fetal liver cell line (HFL cells), and in hepatocytes. CYP3A4 mRNA could be detected in iPSHCs, but the expression level was very low compared with those in HepG2 cells and hepatocytes. However, the CYP3A4 mRNA levels markedly increased on introduction of HNF6 and reached one-tenth of those in hepatocytes. We also found that HNF6 introduction increased CYP3A4 gene transcription in HFL cells and HepG2 cells, which have features similar to those of fetal hepatocyte-like cells; however, it did not affect CYP3A4 mRNA expression in hepatocytes. These results suggest that HNF6 plays an important role in the gene regulation of CYP3A4 during development from the fetal period to the postnatal period.


Subject(s)
Cytochrome P-450 CYP3A/biosynthesis , Hepatocyte Nuclear Factor 6/pharmacology , Cell Differentiation , Cell Line , Hep G2 Cells , Hepatocytes/drug effects , Hepatocytes/metabolism , Humans , Induced Pluripotent Stem Cells , RNA, Messenger/metabolism , Transcriptional Activation/drug effects
19.
Drug Metab Pharmacokinet ; 28(1): 38-43, 2013.
Article in English | MEDLINE | ID: mdl-23165864

ABSTRACT

The teratogenic effects of thalidomide have been studied for more than 50 years. However, there have been few studies of the pharmacokinetic changes occurring during thalidomide therapy. Thalidomide was originally developed as a sedative. However, thalidomide induces multiple birth defects when used in pregnant women. Thalidomide is now used in the treatment of multiple myeloma (MM) and erythema nodosum leprosum (ENL) in Japan. Rational use of thalidomide is problematic due to a lack of basic research regarding its mechanism of action and serum concentration/effect relationships. There are a number of hypotheses for pharmacokinetic changes in thalidomide therapy. Genetic factors including single nucleotide polymorphisms (SNPs) that change cytochrome P450 (CYP) activity and epigenetic regulation that modifies CYP expression levels may contribute to the changes in pharmacokinetics and adverse drug reactions (ADRs) of thalidomide. Environmental factors include the pharmacological context of drug-drug interactions and the physiological context of liver diseases. Liver and kidney diseases do not play important roles in pharmacokinetic changes or ADRs in thalidomide therapy. To date, most research has focused on teratogenic activity, while the impact of polymorphisms in genes encoding drug metabolic enzymes and drug-drug interactions could mediate ADRs. Here, we discuss clinical evidence of pharmacokinetic changes in thalidomide therapy.


Subject(s)
Thalidomide/pharmacokinetics , Aryl Hydrocarbon Hydroxylases/genetics , Cytochrome P-450 CYP2C19 , Female , Food-Drug Interactions , Humans , Kidney Diseases/metabolism , Liver Diseases/metabolism , Male , Sex Characteristics , Thalidomide/adverse effects
20.
Dig Dis Sci ; 58(5): 1383-9, 2013 May.
Article in English | MEDLINE | ID: mdl-23179158

ABSTRACT

BACKGROUND: Effective and safe sedation for patients with liver cirrhosis is problematic. AIM: To examine the safety and effectiveness of low-dose propofol sedation during and after esophagogastroduodenoscopy (EGD) in cirrhotic patients. METHODS: Study 1 was a prospective study in cirrhotic patients who underwent diagnostic EGD under propofol sedation. Propofol was given by bolus injection with an age-adjusted standard protocol consisting of 40 mg for patients <70 years, 30 mg for patients aged 70-89 years; additional injections of 20 mg propofol were given up to a maximum of 120 mg. The principal parameter was the occurrence of adverse events within 24 h after EGD. Secondary parameters included successful procedures, complications, and full recovery within 60 min. In Study 2, the residual effects of propofol were evaluated using a driving simulator and blood propofol concentrations in a subset of cirrhotic patients undergoing EGD and compared with healthy individuals. The principal parameter was driving ability. RESULTS: Study 1: Consecutive cirrhotic patients were entered and all 163 successfully completed EGD. The mean dose of propofol was 46 mg (range 30-120 mg). No complications occurred. Full recovery had occurred in 100 % 60 min after the procedure. No adverse events occurred within 24 h after EGD. Study 2: There were no significant differences in blood propofol levels between cirrhotic patients (n = 21) and healthy individuals (n = 20) after sedation. In cirrhotic patients, there was no deterioration in driving ability as compared with healthy individuals. CONCLUSION: Low-dose propofol sedation provided safe and effective sedation for EGD in cirrhotic patients with rapid recovery.


Subject(s)
Endoscopy, Gastrointestinal , Hypnotics and Sedatives/adverse effects , Liver Cirrhosis/complications , Propofol/adverse effects , Adult , Aged , Aged, 80 and over , Automobile Driving , Case-Control Studies , Female , Humans , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/blood , Male , Middle Aged , Propofol/administration & dosage , Propofol/blood , Prospective Studies
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