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1.
J Infect Chemother ; 24(10): 834-840, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30087007

ABSTRACT

In recent years, augmented renal clearance (ARC), in which renal function is excessively enhanced, has been reported, and its influence on ß-lactam antibiotics has been investigated. In this study, we aimed to determine the optimum population pharmacokinetic model of meropenem in patients with sepsis with ARC, and evaluated dosing regimens based on renal function. Seventeen subjects (6 with ARC and 11 without) were enrolled in this study. Predicted meropenem concentrations were evaluated for bias and precision using the Bland-Altman method. To examine the dosing regimen, Monte Carlo simulation was performed to calculate the cumulative fraction of response (CFR). In patients with ARC, the bias (average of the predicted value and measured value residuals) of models constructed by Crandon et al. (2011), Roberts et al. (2009), and Jaruratanasirikul et al. (2015) were 5.96 µg/mL, 10.91 µg/mL, and 4.41 µg/mL, respectively. Following 2 g meropenem every 8 h (180 min infusion), CFR ≥ 90%, a criterion of success for empirical therapy, was achieved, even with creatinine clearance of 130-250 mL/min. For patients with sepsis and ARC, the model of Jaruratanasirikul et al. showed the highest degree of accuracy and precision and confirmed the efficacy of the meropenem dosing regimen in this patient population.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacokinetics , Kidney/physiology , Meropenem/administration & dosage , Meropenem/pharmacokinetics , Sepsis/drug therapy , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/blood , Creatinine/blood , Creatinine/urine , Female , Hospitals, University , Humans , Intensive Care Units , Male , Meropenem/blood , Metabolic Clearance Rate , Middle Aged , Monte Carlo Method , Treatment Outcome
2.
Article in English | MEDLINE | ID: mdl-27190632

ABSTRACT

BACKGROUND: We formulated mianserin suppositories for the treatment of delirium and evaluated their pharmacokinetics by measuring plasma drug concentrations in dogs and healthy human volunteers. METHODS: Mianserin suppositories were prepared by a melting technique using Tetramide® tablets and Witepsol H-15 as the suppository base. Pharmacokinetics of this 30-mg mianserin preparation were evaluated in three beagle dogs and three healthy adult males, in line with ethics committee approval. Plasma mianserin levels were determined using gas chromatography-mass spectrometry. RESULTS: In dogs, the maximum plasma mianserin concentration (Cmax) was 1.3 ± 0.4 ng/mL, the time to Cmax (tmax) was 5.5 ± 4.3 h, and the area under the plasma concentration-time curve from 0 to 24 h (AUC0-24) was 18.9 ± 1.9 h・ng/mL. In humans, the Cmax was 14.6 ± 6.3 ng/mL, the tmax was 8 h, and the AUC0-24 was 266 ± 103 h・ng/mL. CONCLUSIONS: The current study characterized the pharmacokinetics of mianserin suppositories in dogs and humans. As compared to oral administration, the suppositories produced a lower Cmax and a delayed tmax, although AUC0-24 values were comparable. It will be necessary to identify an appropriate dose that produces an adequate plasma mianserin concentration for effective and safe clinical use. TRIAL REGISTRATION: UMIN000013853.

3.
PLoS One ; 11(3): e0151601, 2016.
Article in English | MEDLINE | ID: mdl-26978524

ABSTRACT

BACKGROUND: We aimed to identify associations between erythroferrone (ERFE), a regulator of hepcidin 25, and biomarkers of erythropoiesis and iron metabolism. We also aimed to determine the effects of erythropoiesis-stimulating agents (ESA), continuous erythropoietin receptor activator (CERA) and darbepoetin-α (DA) on ERFE production in patients on hemodialysis (HD). METHODS: Blood samples were obtained from 59 patients before HD sessions on day 0 (baseline). Twenty patients who were injected with either CERA (N = 10) or DA (N = 10) at the end of the dialysis week (day 0), who had ferritin ≥ 100 ng/mL and/or transferrin saturation ≥ 20%, and hemoglobin > 9 g/dL were selected from among the 59 patients. Blood was sampled serially before HD sessions on days 3, 5, 7 from patients on DA and on the same days plus day 14 from those on CERA. RESULTS: Levels of ERFE correlated inversely with those of hepcidin 25 and ferritin, and positively with those of soluble transferrin receptor. The hepcidin 25: ERFE ratio and hepcidin 25 levels positively correlated with ferritin levels. Levels of ERFE significantly increased from day 3 of treatment with DA and CERA and decreased by days 7 and 14, respectively. Erythropoiesis-stimulating agents concomitantly decreased levels of hepcidin 25 as those of ERFE increased. CONCLUSION: We identified a novel association between ESA and ERFE in patients on HD. Both DA and CERA increased levels of ERFE that regulated hepcidin 25 and led to iron mobilization from body stores during erythropoiesis.


Subject(s)
Anemia/prevention & control , Darbepoetin alfa/pharmacology , Erythropoiesis/physiology , Erythropoietin/pharmacology , Hematinics/pharmacology , Hepcidins/blood , Iron/blood , Peptide Hormones/physiology , Polyethylene Glycols/pharmacology , Renal Dialysis , Aged , Aged, 80 and over , Anemia/etiology , Biomarkers , Cross-Sectional Studies , Darbepoetin alfa/therapeutic use , Erythropoiesis/drug effects , Erythropoietin/therapeutic use , Female , Ferritins/blood , Hematinics/therapeutic use , Hemoglobins/analysis , Hepcidins/biosynthesis , Hepcidins/genetics , Humans , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/therapy , Male , Middle Aged , Peptide Hormones/biosynthesis , Polyethylene Glycols/therapeutic use , Prospective Studies , Receptors, Transferrin/blood , Renal Dialysis/adverse effects , Reticulocyte Count , Time Factors , Transferrin/analysis
4.
J Toxicol Sci ; 41(Special): SP89-SP103, 2016.
Article in English | MEDLINE | ID: mdl-28320986

ABSTRACT

A wide variety of drugs and chemicals have been shown to produce induction and inhibition of heme-metabolizing enzymes, and of drug-metabolizing enzymes, including cytochrome P450s (P450s, CYPs), which consist of many molecular species with lower substrate specificity. Such chemically induced enzyme alterations are coordinately or reciprocally regulated through the same and/or different signal transductions. From the toxicological point of view, these enzymatic changes sometimes exacerbate inherited diseases, such as precipitation of porphyrogenic attacks, although the induction of these enzymes is dependent on the animal species in response to the differences in the stimuli of the liver, where they are also metabolized by P450s. Since P450s are hemoproteins, their induction and/or inhibition by chemical compounds could be coordinately accompanied by heme synthesis and/or inhibition. This review will take a retrospective view of research works carried out in our department and current findings on chemical-induced changes in hepatic heme metabolism in many places, together with current knowledge. Specifically, current beneficial aspects of induction of heme oxygenase-1, a rate-limiting heme degradation enzyme, and its relation to reciprocal and coordinated changes in P450s, with special reference to CYP2A5, in the liver are discussed. Mechanistic studies are also summarized in relation to current understanding on these aspects. Emphasis is also paid to an example of a single chemical compound that could cause various changes by mediating multiple signal transduction systems. Current toxicological studies have been developing by utilizing a sophisticated "omics" technology and survey integrated changes in the tissues produced by the administration of a chemical, even in time- and dose-dependent manners. Toxicological studies are generally carried out step by step to determine and elucidate mechanisms produced by drugs and chemicals. Such approaches are correct; however, current "omics" technology can clarify overall changes occurring in the cells and tissues after treating animals with drugs and chemicals, integrate them and discuss the results. In the present review, we will discuss chemical-induced similar changes of heme synthesis and degradation, and of P450s and finally convergence to similar or different directions.


Subject(s)
Cytochrome P-450 Enzyme System/biosynthesis , Heme/metabolism , Liver/enzymology , Liver/metabolism , Organic Chemicals/pharmacology , Organic Chemicals/toxicity , Aminolevulinic Acid , Animals , Enzyme Induction , Heme/biosynthesis , Heme Oxygenase (Decyclizing) , Heme Oxygenase-1/metabolism , Humans , Rodentia , Toxicology , Transcription Factors
5.
Ther Apher Dial ; 19(6): 582-9, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26481900

ABSTRACT

Continuous erythropoietin receptor activator (CERA) and darbepoetin-α (DA) might differently affect iron metabolism and erythropoiesis in patients on hemodialysis (HD). This prospective study examined a cohort of patients on HD who had received either intravenous CERA every 2 or 4 weeks (N = 25) or DA once each week (N = 47). Blood was sampled before HD sessions on days 0, 2, 4, 7 and 14, and on days 0, 3, 5, 7 and 14 from patients who were injected with ESA at the beginning and end of the dialysis week, respectively. Changes in factors indicating erythropoiesis and biomarkers of iron metabolism were examined. Hemoglobin levels were maintained in the target range between 10.0 and 11.0 g/dL and ferritin levels at baseline and during the study period were similar between the DA and CERA groups. Levels of hepcidin 25 decreased from days 2-3 to day 5 and returned to the baseline at day 7 in the DA group, whereas those and transferrin saturation were serially suppressed from days 2-3 to day 14 in the CERA group. Levels of soluble transferrin receptor and reticulocyte counts were significantly elevated from days 4-5 to day 14 by CERA. Both DA and CERA stabilized erythropoiesis, but CERA might mobilize iron from body stores more effectively than DA in patients on HD.


Subject(s)
Darbepoetin alfa/therapeutic use , Erythropoietin/therapeutic use , Hematinics/therapeutic use , Iron/metabolism , Polyethylene Glycols/therapeutic use , Renal Dialysis , Aged , Biomarkers/blood , Female , Hepcidins/blood , Humans , Male , Middle Aged , Transferrin/metabolism
6.
J Toxicol Sci ; 39(2): 319-30, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24646714

ABSTRACT

Epithelial-mesenchymal transition (EMT) plays a pivotal event in the development of pulmonary fibrosis. We have previously reported that methotrexate (MTX)-induced alveolar epithelial cell injury followed by pulmonary fibrosis as a result of the recruitment and proliferation of myofibroblasts. However, there is no data concerning whether EMT occurs in MTX-induced pulmonary fibrosis. In the present study, therefore, we investigated the expression of EMT markers such as E-cadherin, α-SMA, and vimentin by immunofluorescence analysis in mouse lung tissues after administration of MTX. We found that vimentin and α-SMA-positive cells of the MTX-induced pulmonary fibrosis were increased; on the other hand, E-cadherin was decreased, indicating that epithelial cells act as the main source of mesenchymal expansion. These results exhibited the down-regulation of E-cadherin expression and the up-regulation of α-smooth muscle actin (α-SMA) in primary mouse alveolar epithelial cells (MAECs) and A549 cell lines. Additionally, MTX-induced A549 cells exhibited an EMT-like phenotype accompanied by the elevation of the expression of interleukin-6 (IL-6) and transforming growth factor (TGF)-ß1, as well as an enhancement of migration. All of these findings suggest that MTX-induced pulmonary fibrosis occurs via EMT.


Subject(s)
Epithelial Cells/drug effects , Epithelial Cells/pathology , Epithelial-Mesenchymal Transition/drug effects , Epithelial-Mesenchymal Transition/genetics , Methotrexate/adverse effects , Pulmonary Fibrosis/physiopathology , Actins/metabolism , Animals , Cadherins/metabolism , Cell Proliferation/drug effects , Down-Regulation , Epithelial Cells/metabolism , Humans , Interleukin-6/metabolism , Mice , Myofibroblasts/cytology , Myofibroblasts/drug effects , Myofibroblasts/pathology , Pulmonary Alveoli/cytology , Pulmonary Fibrosis/genetics , Transforming Growth Factor beta1/metabolism , Tumor Cells, Cultured , Up-Regulation , Vimentin/metabolism
7.
Meta Gene ; 2: 686-93, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25606452

ABSTRACT

Human organic solute carrier protein 1 (hOSCP1) is a Na(+)-independent multispecific organic solute transporter. To date, several studies have revealed that gene mutations of the transporters are likely to be associated with some diseases; however, there are no data concerning the genetic polymorphism of the hOSCP1 gene in Japanese patients with non-viral liver carcinoma (LC). In the present study, we isolated genomic DNA from a normal portion of LC, and analyzed 41 single nucleotide polymorphisms (SNPs) chosen from a database of SNPs (dbSNPs). We found genotype frequencies for 2 non-synonymous SNPs [rs34409118 (Thr(131) â†’ Ala) and rs1416840 (Ile(219) â†’ Thr)] and 1 synonymous SNP [rs16822954 (Ser(193) â†’ Ser)] to be statistically significant when compared with dbSNPs. No statistical significance was observed in rs2275477 (Gly(307) â†’ Arg) in the hOSCP1 gene. With respect to the allele frequency, we also observed rs34409118 to be statistically significant. Interestingly, we found that non-viral LC patients do not carry heterozygous mutations in rs1416840 (A/G) and rs16822954 (A/G), suggesting that a non-carrier of heterozygous mutations in these two SNPs might be a biomarker for susceptibility for non-viral LC in Japanese. Further analyses of patients with hOSCP1 variants may elucidate the relationship between the hOSCP1 gene and susceptibility of non-viral LC in Japanese patients.

8.
Drug Metab Dispos ; 41(11): 1883-7, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23935065

ABSTRACT

Monocarboxylate transporter (MCT) 6, encoded by SLC16A5, is a member of the monocarboxylate transporter family. Nateglinide, an oral hypoglycemic agent, quickly reaches the maximal serum concentration after its premeal administration. Although the functional existence of uptake systems for nateglinide in the intestine has been demonstrated, these transport systems have not yet been identified at the molecular level. The aim of this study was to demonstrate the localization of MCT6 in the human small intestine and characterize the transport properties of nateglinide via MCT6. Immunohistochemical analysis of the human small intestine revealed that anti-MCT6 antiserum stained the luminal side of the epithelial cells. When expressed in Xenopus laevis oocytes, MCT6-mediated uptake of [(14)C]nateglinide was sensitive to extracellular pH and membrane potential. Furthermore, the K(t) value of nateglinide (45.9 µM) for MCT6 was lower than those previously reported in Caco-2 cells and rat intestinal brush-border membrane vesicles. In addition, probenecid, fluorescein, valproic acid, and salicylic acid, which are inhibitors of nateglinide uptake in Caco-2 cells and rat intestine, did not inhibit the uptake of nateglinide via MCT6. These results suggest that MCT6 may play a role in the intestinal absorption of nateglinide, although other transporters are also likely involved.


Subject(s)
Cyclohexanes/metabolism , Hypoglycemic Agents/metabolism , Intestine, Small/metabolism , Monocarboxylic Acid Transporters/metabolism , Phenylalanine/analogs & derivatives , Animals , Biological Transport/physiology , Caco-2 Cells , Cell Line, Tumor , Female , Humans , Hydrogen-Ion Concentration , Intestinal Absorption/physiology , Membrane Potentials/physiology , Membrane Transport Proteins/metabolism , Nateglinide , Oocytes/metabolism , Phenylalanine/metabolism , Rats , Xenopus laevis/metabolism
9.
J Toxicol Sci ; 38(1): 103-14, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23358144

ABSTRACT

Drug transporters play a pivotal role in the disposition and elimination of a wide variety of organic compounds across the biological membrane of the body. Recent studies have revealed that some drug transporters are involved in drug-induced toxicity. We have previously reported that methotrexate (MTX)-induced cytotoxicity and apoptosis in primary mouse alveolar epithelial cells (MAEC) are more sensitive than primary mouse lung fibroblasts (MLF). In the present study, we investigated the mRNA expression of ABCs, Slco/Slc/Oatp transporters by RT-PCR and quantitative real-time PCR (qRT-PCR) techniques in mouse lung tissues and primary lung cells. The ABC transporters (Mdr1, Mrp1, 3, 4, 5, and Bcrp) and the Slco/Oatp transporters (Rfc, Oatp1a1, 1a4, 1a5, 1b2, 2a1, 2b1, 3a1, 4c1, and 5a1) were detected in mouse lung tissues, whereas some ABCs, Slcs/Oats, and Slco/Oatps transporters were not expressed in the mouse lung. Additionally, we found that some Abc transporters are expressed predominantly in MLF whereas Mrp3 and Oatp4c1 are expressed predominantly in MAEC. The transport activity of [(3)H]MTX mediated via MAEC was significantly higher than the MLF-mediated transport. When MLF was treated with MK571, accumulated [(3)H]MTX significantly increased when compared with MAEC. Thus, our results indicate that depending on the type of cells, several types of drug transporters are expressed in mouse lung tissues. Our results also suggest that MTX-induced fibrosis with cell dysfunction may be caused by the accumulation within the alveolar epithelial cells of MTX in the lung.


Subject(s)
ATP-Binding Cassette Transporters/genetics , Epithelial Cells/drug effects , Fibroblasts/drug effects , Methotrexate/pharmacology , Organic Anion Transporters/genetics , Animals , Antimetabolites, Antineoplastic/pharmacology , Antirheumatic Agents/pharmacology , Cells, Cultured , Epithelial Cells/metabolism , Fibroblasts/metabolism , Folic Acid Antagonists/pharmacology , Gene Expression Regulation/drug effects , Lung/cytology , Male , Mice , Mice, Inbred C57BL , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction
10.
J Toxicol Sci ; 37(4): 699-709, 2012.
Article in English | MEDLINE | ID: mdl-22863851

ABSTRACT

In the present study, we isolated and determined the pharmacological characteristics of a novel gene encoding the zinc finger-like protein (ZfLp). The isolated cDNA consisted of 1,581 base pairs that encoded a 526-amino acid protein. The amino acid sequence of ZfLp is 96% identical to that of zinc finger protein 415 isoform 5 (ZNF415-5). Reverse-transcription (RT)-polymerase chain reaction (PCR) analysis revealed that the ZfLp mRNA is expressed in the breast, lung, stomach, small intestine colon and ovary, but not in the liver. When expressed in Xenopus laevis oocytes, ZfLp mediated the high affinity transport of [(3)H]paclitaxel (taxol) in a sodium-independent manner (K(m) = 336.7 ± 190.0 nM). The uptake of [(3)H]paclitaxel (taxol) by ZfLp was trans-stimulated by glutarate and glutathione (GSH). A cis-inhibition experiment revealed that ZfLp-mediated transport of [(3)H]paclitaxel (taxol) is inhibited by several organic solutes specifically clotrimazole. Using several clotrimazole derivatives, we found that N-benzylimidazole would be a minimum unit for producing the inhibition of ZfLp-mediated drug uptake. Our results may provide insights into the novel role of soluble protein, such as ZNF, in the human body. Our results, therefore, would be expected to facilitate research on the novel role of ZNFs and on the discovery of novel drugs for targeting ZNF-related proteins such as ZfLp.


Subject(s)
Oocytes/metabolism , Transcription Factors/metabolism , Xenopus laevis/genetics , Zinc Fingers/genetics , Amino Acid Sequence , Animals , Base Sequence , Biological Transport , Cloning, Molecular , DNA, Complementary/genetics , Female , Gene Expression Regulation , Gene Library , Humans , Imidazoles/chemistry , Molecular Sequence Data , Paclitaxel/pharmacokinetics , Phylogeny , RNA, Messenger/genetics , RNA, Messenger/metabolism , Substrate Specificity , Transcription Factors/genetics , Xenopus laevis/metabolism
11.
Yakugaku Zasshi ; 131(10): 1493-501, 2011.
Article in Japanese | MEDLINE | ID: mdl-21963977

ABSTRACT

In the present study, we isolated and determined the pharmacological characteristics of a novel gene encoding the human prostaglandin carrier (hPrC). The isolated cDNA consisted of 1431 base pairs that encoded a 477-amino acid protein, and we found that isolated hPrC does not belong to any drug transporter families. RT-PCR analysis revealed that the hPrC mRNA is expressed in various human tissues ubiquitously. When expressed in Xenopus laevis oocytes, hPrC mediated the transport of [(3)H]prostaglandin E(2) (PGE(2)) in a sodium-independent manner. The uptake of [(3)H] PGE(2) was not trans-stimulated by PG analogous. Although there are several PG transporters such as multidrug resistance-associated protein 4 (MRP4), organic cation transporter 1 (OCT1) [solute carrier (SLC) 22A1], organic anion transporter 1-3 (OAT1-3) [SLC22A6-8], OAT4 [SLC11], OATP-1 (LST-1) [SLCO1B1], OATP2B1 [SLCO2B1], OATP2A1 (PGT) [SLCO2A1], OATP4A1 (OATP-E) [SLCO4A1] have been isolated and well characterized, our findings suggest that hPrC functions as a novel transport peptide responsible for PG uptake. Our results should provide insight into the novel mechanism of the PG transport in the human body.


Subject(s)
Biological Transport/genetics , Cloning, Molecular , Dinoprostone/metabolism , Organic Anion Transporters/genetics , Organic Anion Transporters/physiology , Animals , DNA, Complementary/genetics , DNA, Complementary/isolation & purification , Female , Gene Library , Humans , Organic Anion Transporters/chemistry , Placenta , Pregnancy , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence Analysis, Protein , Time Factors , Xenopus laevis
12.
J Toxicol Sci ; 35(6): 827-34, 2010 Dec.
Article in English | MEDLINE | ID: mdl-21139332

ABSTRACT

Ribosomal protein L3 (RPL3) is known to be an indispensable and essential component for the peptidyltransferase center. In the present study, we found a novel function of RPL3 using a Xenopus laevis oocyte expression system. When expressed in X. oocytes, RPL3 mediated the high affinity transport of [(3)H]digoxin (K(m) = 213.3 ± 46.8 nM) in a time-, concentration-, and sodium-dependent manners. The maximum velocity of the transport of [(3)H]digoxin via RPL3 produced at physiological pH. However, we did not observe RPL3-mediated transport of several organic solutes such as [(14)C]androstenedione, [(3)H]dexamethasone, [(3)H]dehydroepiandrosterone sulfate, [(3)H]L-tryptophan, [(14)C]L-ascorbic acid, [(14)C]α-ketoglutarate, [(14)C]glutarate, [(3)H]methotrexate, [(3)H]bumetanide, [(3)H]probenecid, [(14)C]salicylic acid, [(14)C]theophylline and [(3)H]valproate. Our results suggest that RPL3 functions as a drug carrier protein and may be involved in the digoxin toxicity in the human body.


Subject(s)
Carrier Proteins/physiology , Digoxin/metabolism , Oocytes/metabolism , Ribosomal Proteins/physiology , Animals , Biological Transport , Carrier Proteins/biosynthesis , DNA, Complementary/biosynthesis , Digoxin/pharmacokinetics , Digoxin/toxicity , Dose-Response Relationship, Drug , Humans , In Vitro Techniques , Kinetics , RNA, Complementary/biosynthesis , Ribosomal Protein L3 , Ribosomal Proteins/biosynthesis , Tritium , Xenopus laevis
13.
J Toxicol Sci ; 35(5): 653-61, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20930460

ABSTRACT

Methotrexate (MTX) has been used as the first-line disease-modifying antirheumatic drug (DMARD) in patients with early progressive rheumatoid arthritis (RA). Several severe side effects such as myelosuppression, hepato-, nephro-, and pulmonary toxicities have been reported. However, the pathogenic mechanism of MTX-induced pulmonary fibrosis is still unknown. Here, we evaluated the morphological and biological changes of the pulmonary fibrosis in mice treated with MTX. Three, four and five weeks after consecutive administration of MTX (3 mg/kg/day), hydroxyproline content in the lung tissues increased significantly to about 2 times higher that of the control level. This result closely reflected to the results of hematoxylin and eosin (HE) and Azan stains. Immunohistochemical analysis revealed that MTX treatment resulted in a decrease of alveolar epithelial cells and an increase of fibroblast cells in the mouse lung tissues. When we examined the effects of MTX on primary mouse alveolar epithelial cell (MAEC) and mouse lung fibroblast (MLF) survival in vitro, the efficiency of MTX-induced cytotoxicity and apoptosis in MAEC was more sensitive than MLF cells. Thus, our results indicate that the administration of MTX by an oral route could induce a fibrotic response with cell dysfunction of the alveolar epithelium by which MTX-induced apoptosis. Our results thus suggest that MTX could induce alveolar epithelial cell injury and resulted in the loss of integrity of the alveolar-capillary barrier basement membranes followed by the recruitment and proliferation of myofibroblasts with the deposition of collagens.


Subject(s)
Disease Models, Animal , Lung/drug effects , Methotrexate/toxicity , Pulmonary Fibrosis/chemically induced , Animals , Apoptosis/drug effects , Blood Cell Count , Bone Marrow/drug effects , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/pathology , Fibroblasts/drug effects , Fibroblasts/metabolism , Fibroblasts/pathology , Hydroxyproline/metabolism , Immunohistochemistry , In Situ Nick-End Labeling , Lung/metabolism , Lung/pathology , Male , Mice , Mice, Inbred C57BL , Pulmonary Alveoli/drug effects , Pulmonary Alveoli/metabolism , Pulmonary Alveoli/pathology , Pulmonary Fibrosis/blood , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/pathology
14.
Drug Metab Dispos ; 38(9): 1576-81, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20566696

ABSTRACT

The aim of the present study was to characterize the mechanism of erythromycin transport at the blood-placenta barrier, using TR-TBT 18d-1 cells as a model of rat syncytiotrophoblasts. [(14)C]Erythromycin was taken up by TR-TBT 18d-1 cells with a Michaelis constant of 466 microM. Although the uptake was not dependent on extracellular Na(+) or Cl(-), it was increased at weakly alkaline pH. Significant overshoot of [(14)C]erythromycin uptake by placental brush-border membrane vesicles was observed in the presence of an outwardly directed proton gradient. These results indicate that erythromycin is transferred by the H(+)-coupled transport system in syncytiotrophoblasts. To address the physiological transport of erythromycin in rat placenta, fetal-to-maternal transport clearance was estimated by means of the single placental perfusion technique. Clearance of [(14)C]erythromycin was higher than that of [(14)C]inulin, a paracellular pathway marker, and was decreased by the addition of 5 mM erythromycin, indicating that saturable efflux system from fetus to mother is involved. The effect of various transporter inhibitors on [(14)C]erythromycin efflux from TR-TBT 18d-1 cells was evaluated. cyclosporin A, fumitremorgin C, and probenecid had no effect, whereas ethylisopropylamiloride, a specific inhibitor of Na(+)/H(+) exchangers (NHEs), was significantly inhibitory. These results suggest that erythromycin efflux transport at the rat blood-placenta barrier is mediated by an erythromycin/H(+) antiport system, driven by H(+) supplied by NHEs.


Subject(s)
Erythromycin/pharmacokinetics , Maternal-Fetal Exchange , Animals , Female , Pregnancy , Protons , Rats
15.
Drug Metab Dispos ; 38(9): 1427-35, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20547965

ABSTRACT

In the present study, we isolated and determined the pharmacological characteristics of a novel gene encoding the lambda light chain of human Ig surface antigen-related gene (IgLC-rG). The isolated cDNA consisted of 693 base pairs that encoded a 232-amino acid protein. Northern blot analysis revealed that the IgLC-rG mRNA is expressed in the adult spleen and small intestine but not in fetal tissues. When expressed in Xenopus laevis oocytes, IgLC-rG mediated the high-affinity transport of [(3)H]cyclosporin A (CsA) (K(m) = 189.7 +/- 123.5 nM) in a sodium-dependent manner; however, other organic solutes such as p-aminohippuric acid and TEA were not transported via IgLC-rG. The transport of [(3)H]CsA by IgLC-rG was sensitive to pH. The uptake of [(3)H]CsA was trans-stimulated by CsA and GSH. Immunohistochemical analysis revealed that the IgLC-rG protein is localized at the brush border membrane in the human small intestine. Although the isolated IgLC-rG gene is a member of the human Ig lambda light chain surface antigen superfamily, our findings suggest that IgLC-rG functions as a novel transport peptide responsible for CsA in the human body. Our results should provide insight into the novel function of membrane-bound proteins, such as Igs.


Subject(s)
Antigens, Surface/metabolism , Cyclosporine/metabolism , Immunoglobulin lambda-Chains/metabolism , Amino Acid Sequence , Animals , Antigens, Surface/genetics , Antigens, Surface/immunology , Base Sequence , DNA, Complementary , Expressed Sequence Tags , Humans , Immunoglobulin lambda-Chains/immunology , Immunohistochemistry , Kinetics , Molecular Sequence Data , Xenopus laevis
16.
Life Sci ; 84(1-2): 45-51, 2009 Jan 02.
Article in English | MEDLINE | ID: mdl-19032958

ABSTRACT

AIMS: We isolated a novel gene encoding human nucleoside transporter 1 (hNT1), from a human breast cancer cDNA library. MAIN METHODS: A nondirectional cDNA library was screened by an EST clone (GenBanktrade mark/EMBL/DDBJ: BU944345). A Xenopus laevis oocyte expression system was used for functional characterization. Membrane localization in the human breast was determined by immunohistochemistry. KEY FINDINGS: Isolated hNT1 cDNA consisted of 246 base pairs that encoded an 82-amino acid protein. By RT-PCR analysis, hNT1 mRNA was strongly detected in the breast cancer tissues. When expressed in X. oocytes, hNT1 mediated the high affinity transport of [(3)H]5-fluorouracil (5-FU) with a K(m) value of 69.2+/-24.5 nM in time- and pH-dependent, and Na(+)-independent manners. A cis-inhibition experiment revealed that hNT1 mediated transport of [(3)H]5-FU is strongly inhibited by various nucleosides such as pyrimidine, uracil, uridine, guanosine, inosine, thymidine, adenosine, cytidine and purine suggesting that hNT1 may be involved in the trans epithelial transport of these endogenous substrates. Immunohistochemical analysis revealed that the hNT1 protein is localized in the lactiferous duct epithelium. SIGNIFICANCE: Our present results indicate that a newly isolated cDNA clone, hNT1, is a key molecule for the breast handling of 5-FU in humans.


Subject(s)
Breast Neoplasms/metabolism , Gene Library , Nucleoside Transport Proteins/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Fluorouracil/pharmacokinetics , Humans , Immunohistochemistry , Molecular Sequence Data , Nucleoside Transport Proteins/analysis , Nucleoside Transport Proteins/physiology
17.
Yakugaku Zasshi ; 128(9): 1301-9, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18758144

ABSTRACT

Over-the-counter medications are primarily for self-medication, where the seller, such as a pharmacist, provides the necessary information and the consumer uses the medication at his or her own discretion based on the information provided. A Web survey was conducted from February 8 to 13, 2006, involving 500 men and women, ranging in age from 50 to 69 years, who had purchased over-the-counter medications for the common cold within the past 3 years. Upon consultation with and purchase of a cold medication from a pharmacist, 84.2% of respondents reported "being asked my symptoms," and less frequently (12.3-21.3%) being asked about contraindications/careful administration. Most respondents (60.8%) when asked whether they confirmed "contraindications/careful administration" responded negatively, stating they "occasionally do not confirm" or "do not confirm." In addition, among men aged 50-69 years, it became clear that 6.0% had experienced aggravation of prostatic hypertrophy symptoms after taking a cold medication. It is assumed that symptoms are usually confirmed upon the sale of over-the-counter medications, but the rate of confirming whether the consumer may need to consider contraindications/careful administration is low. Urinary retention is a preventable side effect because the confirmation prior to taking the medication can be made. Accordingly, some of those side effects can be avoided by ensuring the environment for confirming whether the individual corresponds to "contraindications/careful administration" before taking the medication.


Subject(s)
Common Cold/drug therapy , Nonprescription Drugs/administration & dosage , Urologic Diseases/chemically induced , Aged , Contraindications , Female , Humans , Internet , Male , Middle Aged , Nonprescription Drugs/adverse effects , Self Medication/adverse effects , Surveys and Questionnaires , Urologic Diseases/epidemiology
18.
Life Sci ; 81(15): 1183-92, 2007 Sep 22.
Article in English | MEDLINE | ID: mdl-17884105

ABSTRACT

Rat organic solute carrier protein 1 (rOscp1) was isolated from a rat testis cDNA library. Isolated rOscp1 cDNA consisted of 1089 base pairs that encoded a 363-amino acid protein, and the amino acid sequence was 88% and 93% identical to that of human OSCP1 (hOSCP1) and mouse Oscp1 (mOscp1), respectively. The message for rOscp1 is highly detected in rat testis. When expressed in X. oocytes, rOscp1 mediated the high affinity transport of p-aminohippurate (PAH) with a Km value of 15.7+/-1.9 microM, and rOscp1-mediated organic solutes were exhibited in time- and Na+-independent manners. rOscp1 also transported various structurally heterogenous compounds such as testosterone, dehydroepiandrosterone sulfate (DHEA-S), and taurocholate with some differences in substrate specificity compared with hOSCP1. Immunohistochemical analysis revealed that the rOscp1 protein is localized in the basal membrane side of Sertoli cells as observed in mouse testis [Kobayashi et al., 2007; Kobayashi, Y., Tsuchiya, A., Hayashi, T., Kohyama, N., Ohbayashi, M., Yamamoto, T., 2007. Isolation and characterization of polyspecific mouse organic solute carrier protein 1 (mOscp1). Drug Metabolism and Disposition 35 (7), 1239-1245]. Thus, the present results indicate that a newly isolated cDNA clone, rOscp1, is a polyspecific organic solute carrier protein with some differences in substrate specificity compared with human and mouse OSCP1.


Subject(s)
Membrane Transport Proteins , Oocytes/metabolism , Testis/metabolism , p-Aminohippuric Acid/metabolism , Amino Acid Sequence , Animals , Base Sequence , Biological Transport , Blotting, Northern , Cloning, Molecular , Female , Humans , Immunohistochemistry , Kinetics , Male , Membrane Transport Proteins/genetics , Membrane Transport Proteins/isolation & purification , Membrane Transport Proteins/physiology , Mice , Molecular Sequence Data , Organ Specificity , Pharmaceutical Preparations/metabolism , Phylogeny , Rats , Sequence Homology, Amino Acid , Substrate Specificity , Xenopus laevis
19.
Yakugaku Zasshi ; 127(5): 905-17, 2007 May.
Article in Japanese | MEDLINE | ID: mdl-17473534

ABSTRACT

The aim of this study was to analyze students, achievement rate and contents of assessment judged by instructors in objective structured clinical examination (OSCE) attempted at the Faculty of Pharmaceutical Science, Showa University. The OSCE was carried out for fourth-year students in May 28, 2005. In this trial, there were two stations, i.e., counting/measurement dispensing and subsequent audit of dispensed drugs, and 218 students and 31 instructors (as evaluators) participated. We developed a checklist to test students attitudes and skills (two stages) and overall evaluation (five stages). Each student was evaluated by two instructors. Examination time was 8 minutes for drug dispensing, and 4 minutes for the audit of dispensed drug. After the OSCE trial, we analyzed validity of examination time, contents of assessment, and differences in scores between different evaluators. More than half of the students could not finish the examination within the limit of time for dispensing the liquid and cream and audit for dispensed powder. The number of items that 60% of the students achieved was 48 (82.8%). Moreover, 20% of the assessment items did not agree among the evaluators with a disagreement rate of 20% or more. Thus, we distinguished between the items based on the extent of disagreement rates. It was suggested that most of the students achieved such a level to actually perform clinical training in pharmacies. From these results, it is necessary to set up an assignment to finish the within the time limit to extent the time limit depending upon examination contents, to standardize the evaluation to increase the agreement rate among evaluators, and to more clearly identify assessment criteria.


Subject(s)
Aptitude Tests , Clinical Competence/statistics & numerical data , Education, Pharmacy/methods , Educational Measurement/methods , Educational Measurement/statistics & numerical data , Educational Status , Faculty , Schools, Pharmacy , Students, Pharmacy , Adult , Clinical Competence/standards , Humans
20.
Cell Transplant ; 16(1): 67-73, 2007.
Article in English | MEDLINE | ID: mdl-17436856

ABSTRACT

Transplantation of isolated hepatocytes has been proposed to compensate for essential functions lacking in liver failure or for genetic defects that alter a specific liver metabolic pathway. Hepatocyte utilization for these purposes would be facilitated with a reliable, reproducible, and effective method of long-term hepatocyte storage. We have recently developed a simple new system for cryopreservation of hepatocytes that encapsulates alginate microspheres and maintains liver-specific function. The aim of this study was to elucidate the transport and drug-metabolizing enzyme activities of cryopreserved microencapsulated hepatocytes stored for a long time. Morphological examinations showed there is no apparent injury of the hepatocytes during cryopreservation processes. A drug-metabolizing enzyme (testosterone 6beta-hydroxylase, a specific probe for CYP3A2) and drug transport activities [salicylate, allopurinol, and prostaglandin E2 (PGE2), typical substrates of rOat2] in cryopreserved microencapsulated hepatocytes were maintained up to 120 days. Our results thus demonstrate for the first time that cryopreservation of primary rat hepatocytes by the encapsulation technique allows long-term retention of drug metabolism and drug transport activities.


Subject(s)
Cryopreservation/methods , Cytochrome P-450 Enzyme System/metabolism , Hepatocytes , Microsomes/metabolism , Steroid Hydroxylases/metabolism , Allopurinol/metabolism , Animals , Biological Transport , Cell Transplantation , Dinoprostone/metabolism , Hepatocytes/cytology , Hepatocytes/enzymology , Hepatocytes/transplantation , Male , Rats , Rats, Sprague-Dawley , Salicylates/metabolism , Time Factors
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