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Nobuhiko Ueda

Publications and source records attributed to Nobuhiko Ueda.

15 recordsLinked to original sources

Involvement of SULT1A3 in elevated sulfation of 4-hydroxypropranolol in Hep G2 cells pretreated with beta-naphthoflavone.

Pretreatment of Hep G2 cells with beta-naphthoflavone (BNF 1-25microM) significantly increased cytosolic sulfation activities of 4-hydroxypropranolol (4-OH-PL) racemate. The profile was similar to those of sulfations towards dopamine and triiodothyronine in the same cytosolic fractions. Kinetic studies of 4-OH-PL sulfation in Hep G2 cytosolic fractions revealed that V(max) values increased but apparent K(m) values remained unchanged following the BNF pretreatment. Among five recombinant human SULT isoforms (SULT1A1, -1A3, -1B1, -1E1 and -2A1) examined, only SULT2A1 did not show 4-OH-PL sulfation activities under the conditions used. SULT1A3 and -1E1 exhibited an enantioselectivity of 4-OH-R-PL sulfation>4-OH-S-PL sulfation, which agreed with that of BNF-pretreated Hep G2 cells as well as of nontreated cells, whereas SULT1A1 and -1B1 showed a reversed enantioselectivity (R<S). In kinetic studies of 4-OH-PL sulfations by four kinds of human SULT isoforms, apparent K(m) values for SULT1A3 were the lowest, and the parameters were close to those of Hep G2 cytosolic fractions. Real time RT-PCR using TaqMan probes demonstrated that the mRNA levels of SULT1A3 increased following BNF pretreatment, which paralleled the results from Western blotting showing the elevated levels of SULT1A3 proteins. These results suggest that the induction of SULT1A3 is mainly responsible for the elevated 4-OH-PL sulfation activities following the pretreatment of Hep G2 cells with BNF.

Arylsulfotransferase↗

Soybean oil in total parenteral nutrition maintains albumin and antioxidant enzyme mRNA levels.

Changes in albumin and antioxidant enzyme mRNA expression in infant rat liver following administration of total parenteral nutrition (TPN) with/without soybean oil emulsion were studied. Infant rats were divided into three groups: group 1=oral diet, group 2=TPN without fat, and group 3=TPN with 20% of calories from soybean oil emulsion. The period of TPN administration was 4 d. Serum aspartate aminotransferase and alanine aminotransferase levels were higher in group 2 than in the other groups, with similar levels seen in the other groups. Albumin, Cu, Zn-superoxide dismutase, and glutaredoxin 1 mRNA expression levels were lower in group 2 than in the other groups, with similar levels seen in the other groups. Catalase mRNA expression was higher in group 1 than in the other groups, with the lowest level seen in group 2. Soybean oil emulsion should be included in TPN regimens to prevent down-regulation of albumin and antioxidant enzyme mRNA expression.

Albumins↗

Soybean oil fat emulsion prevents cytochrome P450 mRNA down-regulation induced by fat-free overdose total parenteral nutrition in infant rats.

Changes in the mRNA expression of hepatic cytochrome P450 (CYP) isoenzymes associated with overdose of fat-free or fat-containing total parenteral nutrition (TPN) were investigated in infant rats. Three-week-old male Sprague-Dawley rats were divided into three groups: group 1 received an oral diet, group 2 received TPN without fat, and group 3 received TPN with 20% of calories from fat (soybean oil emulsion). After TPN administration for 4 d, serum aspartate aminotransferase (AST) levels in group 2 were significantly increased (p<0.01) compared with the other groups. The mRNA expression of hepatic CYP isoenzymes in group 2 decreased to 0.76 to 31% of that in group 1 (p<0.01), but that in group 3 was maintained at 32 to 84% of that in group 1. These results indicate the importance of including fat in TPN regimens to prevent not only hepatic dysfunction but also mRNA down-regulation of liver CYP isoenzymes.

Animals↗

Major role of soybean oil in preventing decrease in CYP4A1 mRNA content relative to PPARalpha mRNA down-regulation in infant rats.

Changes in the levels of CYP4A1, PPARalpha, and RXRalpha mRNA expression in the liver following overdose of fat-free or fat-containing total parenteral nutrition (TPN) were studied in 3-week-old male Sprague-Dawley rats. The rats were divided into three groups: group 1, oral diet; group 2, fat-free TPN; and group 3, TPN with 20% of calories from soybean oil emulsion. Levels of CYP4A1, PPARalpha, and RXRalpha mRNA in the fat-free TPN group were significantly lower than those in the other groups. Levels of CYP4A1 and PPARalpha mRNA were strongly correlated (r=0.849), and levels of CYP4A1 and RXRalpha mRNA were weakly correlated (r=0.618). This is the first report of a strong correlation between the levels of CYP4A1 and PPARalpha mRNA following overdose of fat-free or fat-containing TPN in infant rats. Our results also indicate that it is important to include fat in TPN regimens in order to prevent CYP4A1 mRNA down-regulation, which may be related to changes in PPARalpha mRNA levels in the liver.

Animals↗

Expression of multidrug resistance proteins and accumulation of cisplatin in human non-small cell lung cancer cells.

In order to understand and overcome multidrug resistance (MDR) of human non-small cell lung cancer (NSCLC), mRNA and protein expression levels of P-glycoprotein (MDR1), multidrug resistance-associated protein 1 (MRP1), and lung resistance-related protein (LRP) were investigated and compared with the chemosensitivity and the intracellular/intranuclear cisplatin accumulation of three NSCLC cell lines (Ma-10, Ma-31, and Ma-46). Ma-31 was more resistant than Ma-10 and Ma-46 to cisplatin, carboplatin, etoposide, and paclitaxel. The mRNA level of MDR1 was extremely low, and MDR1 protein was not detected in all cell lines. MRP1 mRNA expression was highest in Ma-31 and lowest in Ma-10, but there was no notable difference between the MRP1 protein expression in three cell lines. LRP mRNA/protein was equally expressed in Ma-10 and Ma-31, but was nominal in Ma-46. The intracellular/intranuclear cisplatin accumulation of the cells was determined to be Ma-31>Ma-46>Ma-10. Thus, MDR1, MRP1, and LRP mRNA and protein expression levels were not correlated with the chemosensitivity or the intracellular/intranuclear cisplatin accumulation of each cell line. The present results indicate that MDR proteins (MDR1, MRP1, and LRP) may not play an important role in the chemoresistance and drug efflux of NSCLC cells.

Antineoplastic Agents↗

Role of soybean oil fat emulsion in the prevention of hepatic xenobiotic transporter mRNA up- and down-regulation induced by overdose of fat-free total parenteral nutrition in infant rats.

Total parenteral nutrition (TPN) is associated with cholestasis and hepatic steatosis in human infants. The present study focused on the changes in hepatic xenobiotic transporters associated with overdose of fat-free or fat-containing TPN in infant rats. Three-week-old male Sprague-Dawley rats were divided into three groups: group 1 received an oral diet, group 2 received TPN without fat, and group 3 received TPN with 20% of its calories from fat (soybean oil emulsion). After TPN administration for 4 days, both serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, which are indicators of hepatic dysfunction, in group 2 were significantly higher (p<0.001) than those in the other groups, whereas there were no differences between groups 1 and 3 in either serum AST or ALT levels. The serum bilirubin concentration in group 2 was also markedly higher than that in the other groups. Mdr2, Bsep, Mrp2, Mrp6, Oct1, and Oat2 mRNA levels were decreased in group 2 (fat-free TPN) compared with those in group 1 (oral diet), whereas Mdr1b, Mrp1, and Mrp5 mRNA levels were increased. Specifically, the level of Mdr1b mRNA in group 2 was 16 times higher (p<0.001) than that in group 1. On the other hand, the changes in these mRNA expression levels in group 3 (fat-containing TPN) were smaller than those in group 2, and specifically, the expression levels of Mdr1b, Mrp1, Mrp5, Mrp6, and Oat2 mRNA in group 3 were not significantly different from those in group 1. The results of the present study indicate that including fat in the TPN regimen is very important in preventing the mRNA up- and down-regulation of xenobiotic transporters, which is considered to be the main factor responsible for the abnormal hepatic changes such as cholestasis associated with the excessive administration of fat-free TPN.

ATP-Binding Cassette Transporters↗

Overexpression of constitutive signal transducer and activator of transcription 3 mRNA in cisplatin-resistant human non-small cell lung cancer cells.

Non-small cell lung cancer (NSCLC) often shows intrinsic multidrug resistance, which is one of the most serious problems in cisplatin-based adjuvant chemotherapy. Recently, the constitutive activation of signal transducer and activator of transcription (STAT) factors has been found in a variety of human cancers. In the present study, the mRNA expression of STATs in various human NSCLC cell lines was investigated by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) to determine whether STATs can be implicated in cisplatin resistance and apoptosis inducibility. Cisplatin triggered apoptosis in Ma-46 based on biochemical and morphological findings, but not in Ma-31. The mRNA expression of STAT3 was highest in cisplatin-resistant Ma-31 and lowest in cisplatin-sensitive Ma-46. A 6-hour exposure of cancer cells to cisplatin failed to stimulate STAT3 mRNA expression. Therefore, an increased transcriptional level of constitutive STAT3 may be related to the suppressive regulation of the apoptotic pathway in intrinsically chemo-resistant NSCLC cells.

Antineoplastic Agents↗

Indocyanine green angiographic findings in a cytomegalovirus retinitis patient.

BACKGROUND: Recently, the incidence of cytomegalovirus retinitis has increased, but indocyanine green angiography for cytomegalovirus retinitis has not been reported. CASE OUTLINE: The patient, a 51-year-old male, had floaters in both eyes. White active lesions were evident in the mid-periphery of both eyes. In the left eye, an atrophic lesion was also observed. We performed fluorescein angiography and indocyanine green angiography. RESULTS: Active lesions showed hypofluorescence from the early to the late phase on both fluorescein angiography and indocyanine green angiography, suggesting chorioretinal inflammation. Tissue staining of the atrophic lesion was apparent from the early phase on fluorescein angiography and hypofluorescence till the intermediate phase, and tissue staining was evident at the late phase on indocyanine green angiography. These findings suggested inflammation or scarring of the choroid and retinal pigment epithelial injury. CONCLUSION: Indocyanine green angiographic findings in this cytomegalovirus retinitis patient suggested a cytomegalovirus retinitis lesion of the choroid. The significance of these findings is to be determined.

Angiography↗

Cloning and functional expression of a novel marmoset cytochrome P450 2D enzyme, CYP2D30: comparison with the known marmoset CYP2D19.

Using a primer set designed on the cDNA encoding the known marmoset cytochrome P450 2D19 (CYP2D19), a cDNA encoding a novel CYP2D enzyme (CYP2D30) was cloned from the liver of a female marmoset bred at Kyoto University (KYU). In addition, a cDNA encoding CYP2D19 was cloned from the liver of a female marmoset bred at Kagoshima University (KAU). CYP2D30 and CYP2D19 showed homologies of 93.6 and 93.4% in their nucleotide and amino acid sequences, respectively. Reverse transcription polymerase chain reaction (RT-PCR) and digestion with NdeI demonstrated that the KYU-marmoset liver contained mainly mRNA for CYP2D30, while the KAU-marmoset liver contained mainly mRNA for CYP2D19. Marmoset CYP2D30, like human CYP2D6, exhibited high debrisoquine (DB) 4-hydroxylase activity and relatively low DB 5-, 6-, 7- and 8-hydroxylase activities, whereas CYP2D19 lacked DB 4-hydroxylase but exhibited marked 5-, 6-, 7- and 8-hydroxylase activities. The two marmoset recombinant enzymes showed enantioselective bufuralol (BF) 1"-hydroxylase activities, similar to CYP2D6. BF 1"-hydroxylation by CYP2D30 exhibited product-enantioselectivity of (1"R-OH-BF << 1"S-OH-BF), similar to that observed with human CYP2D6, whereas CYP2D19 showed a reversed selectivity of (1"R-OH-BF > or = 1"S-OH-BF). BF 1"-hydroxylation in marmoset liver microsomes from both sources was inhibited by antibodies raised against rat CYP2D1 in a concentration-dependent manner. A known inhibitor of CYP2D6, quinidine, effectively inhibited the BF 1"-hydroxylation activities in liver microsomal fractions prepared from KYU- and KAU-marmosets. These results suggest that CYP2D19 and CYP2D30 proteins can be expressed as functional enzymes in marmoset livers, although it is unresolved whether both enzymes coexist in the same marmoset liver.

Alcohol Oxidoreductases↗

Cytochrome p450 gene expression levels in peripheral blood mononuclear cells in comparison with the liver.

Cytochromes p450 (CYPs) compose a superfamily of similar proteins involved in detoxification and elimination, as well as activation of a wide variety of compounds. Most CYP family members are localized in the liver. In order to assess whether peripheral blood leukocytes (PBL) are available as a surrogate for the determination of CYP gene expression levels in the liver, we compared CYP gene expression levels in PBL with those in liver tissues from patients with hepatocellular carcinoma (HCC). We measured CYP1A1, 1A2, 1B1, 2A6, 2B6, 2C8, 2C9, 2C18, 2C19, 2D6, 2E1, 2F1, 2J2, 3A4, 3A5, 3A7, 4A11, 4B1 and CYP27 gene expressions in PBL and in the liver by real-time reverse-transcription (RT)-PCR. We could detect expression of CYP1A1, 1A2, P1B1, 2A6, 2B6 and 2E1 genes in PBL and all the genes except for CYP2F1 in the liver. Although gene expression levels within each subfamily were closely correlated within PBL and within the liver, a clear correlation of gene expression levels between PBL and liver tissues was found only for CYP4B1. Although inter-individual variation of the expression level of each CYP gene was wide, the induced level was proportional to the basal expression level. Therefore, monitoring of CYP gene expression levels in PBL, especially those of CYP4B1, could be available as a biomarker for monitoring of exposure to environmental pollutants and assessing the associated risk. Compared with non-tumor tissue, HCC tissues tended to show overexpression of multiple CYP genes, indicating that individualized selection and more effective administration of chemotherapeutic agents could perhaps be based on the pattern of CYP overexpression.

Adult↗

Comparative analysis of ATP-binding cassette (ABC) transporter gene expression levels in peripheral blood leukocytes and in liver with hepatocellular carcinoma.

ATP-binding cassette (ABC) transporters comprise a superfamily of similar proteins involved in transmembrane transport of various substances. ABC transporter family members in the liver participate in bile formation and lipid metabolism. In order to assess whether peripheral blood leukocytes (PBL) are available as a surrogate for determination of the expression of ABC transporter genes in the liver, we compared ABC transporter gene expression levels in PBL with those in liver tissues from patients with hepatocellular carcinoma (HCC). We measured ABCA1, A2, B1-B4, C1 degrees C5, G1 and G2 gene expression levels in PBL, and cancerous and non-cancerous portions of liver from patients with hepatocellular carcinoma by means of real time reverse-transcription (RT)-PCR. We could not detect ABCC5 expression in any tissue of the liver. Close correlations between ABCA2, C1 and G1 in PBL and in non-tumor tissues of the liver were found. Compared with the non-tumor part, HCC tissue expressed lower levels of ABCA1, B4 and G2. We think monitoring of ABCA2, C1 and G1 gene expression levels in PBL will be useful for selection of anti-cancer agents and monitoring of drug resistance of HCC. Administration of chemotherapeutic agents which are substrates of ABCA1, B4 and G2 should be effective for the treatment of HCC.

ATP-Binding Cassette Transporters↗

Effect of lansoprazole and rabeprazole on tacrolimus pharmacokinetics in healthy volunteers with CYP2C19 mutations.

The aim of this study was to investigate the effects of the proton pump inhibitors (PPIs), lansoprazole and rabeprazole, on tacrolimus pharmacokinetics in healthy volunteers with mutations in the cytochrome P450 (CYP) 2C19 gene (CYP2C19). An open-label crossover study was performed with 19 healthy subjects. Tacrolimus (2 mg) was administered orally with and without lansoprazole (30 mg per day for 4 days) or rabeprazole (10 mg per day for 4 days). Blood concentrations of tacrolimus were determined before and 1, 2, 4 and 8 h after dosing. Genotyping for CYP2C19 was conducted by a polymerase chain reaction-restriction fragment length polymorphism method. Coadministration of lansoprazole significantly decreased the oral tacrolimus clearance, resulting in an increase in the area under the blood concentration-time curve (AUC0-8) (control vs with lansoprazole: 29.7 +/- 3.5 vs 44.1 +/- 5.0 ng h mL(-1), P < 0.05). Large individual variation was observed in the effects of lansoprazole on tacrolimus AUC0-8 owing to CYP2C19 genotype status. The percent change for tacrolimus AUC0-8 in subjects with and without CYP2C19 mutant alleles was 81% and 29%, respectively. Coadministration of rabeprazole also increased the mean AUC0-8 of tacrolimus, but the difference was not statistically significant. These observations suggest that drug interaction between tacrolimus and lansoprazole occurs in subjects with higher lansoprazole blood concentrations corresponding to CYP2C19 genetic status. In contrast, rabeprazole has minimal effect on tacrolimus pharmacokinetics regardless of CYP2C19 genotype status.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Effects of dimethyl sulfoxide on the gene induction of cytochrome P450 isoforms, UGT-dependent glucuronosyl transferase isoforms, and ABCB1 in primary culture of human hepatocytes.

We investigated the gene expression of GAPDH, cytochrome P450 isoforms (CYP1A1, CYP1A2, CYP1B1, CYP2A6, CYP2E1, CYP3A4, CYP3A5, and CYP3A7), UGT-dependent glucuronosyl transferase isoforms (UGT1A6 and UGT1A9), and ABC transporter (ABCB1) after exposure to 0.1, 0.5, and 2.5% dimethyl sulfoxide (DMSO). GAPDH mRNA levels after exposure were less than 2 times higher or lower than control levels at all DMSO concentrations. CYP1A1, CYP1B1, CYP2A6, CYP2E1, CYP3A4, CYP3A5, CYP3A7, and UGT1A9 mRNA levels were less than 2 times higher or lower than control levels at 0.1% and 0.5% DMSO. CYP1A2, UGT1A6, and ABCB1 mRNA levels were less than 2 times higher or lower than control levels at all DMSO concentrations. CYP2E1 and CYP3A4 mRNA levels were 2.5-3.2 times and 2.0-3.3 times higher than control levels at 2.5% DMSO, respectively. UGT1A9 mRNA levels were 0.2-0.5 times lower than control levels at 2.5% DMSO. Exposure to beta-naphthoflavone reduced CYP1A1 mRNA levels in a concentration-dependent manner for donors 1 and 2. Exposure to beta-naphthoflavone reduced CYP1A2 mRNA levels in a concentration-dependent manner for all donors. However, exposure to beta-naphthoflavone increased CYP1B1 mRNA levels for donors 2 and 3 at 2.5% DMSO. Exposure to rifampicin reduced CYP3A4 mRNA levels for all donors at 0.5% and 2.5% DMSO. Exposure to rifampicin also reduced CYP3A5 and CYP3A7 mRNA levels for donors 1 and 3 at 0.5% and 2.5% DMSO. In conclusion, a DMSO concentration of 0.1% or less may be appropriate for studying induction after drug exposure.

ATP-Binding Cassette Transporters↗

Tissue distribution of and species differences in deacetylation of N-acetyl-L-cysteine and immunohistochemical localization of acylase I in the primate kidney.

Species differences in the biotransformation of N-acetyl-L-cysteine (NAC) have been investigated to evaluate the usefulness of NAC as a constituent in parenteral nutrition solutions in place of cysteine. The activity of NAC-deacetylating enzyme (acylase) was measured in various tissues of different species (rat, rabbit, dog, monkey, and man). Acylase activity was highest in the kidney in all species studied. Enzyme activity in the liver was 10 %-22 % of that in the kidney in the rat, rabbit, monkey, and man, but almost no hepatic activity was seen in the dog. NAC-deacetylating activity was very low in other organs. The tissue distribution of acylase I was determined by Western blotting and an immunohistochemical method employing specific antibody against porcine acylase I (EC 3.5.1.14). The immunoblotting study showed a 46-kDa protein band corresponding to porcine acylase I in the kidney of all species. In liver cytosol, 46 kDa and/or 29 kDa bands were observed in the rat, rabbit, monkey, and man, but not in the dog. In the immunohistochemical study, positive staining with anti-acylase I antibody was observed clearly in the renal proximal tubules in the monkey and man. These results suggested that the kidney and liver were the main organs responsible for the biotransformation of NAC to cysteine in mammals other than the dog.

Acetylation↗

Effect of enteral nutrition of monoacetoacetin on bacterial translocation in burned rats.

BACKGROUND: Bacterial translocation (BT) occurs under stress, and enteral nutrition is said to be effective in counteracting this effect. The usefulness of i.v. nutrition of monoacetoacetine (MA) under stress has been reported previously, and we studied the effect of enteral nutrition of MA as it is related to BT. METHODS: Rats were given 13.6% MA or 15% glucose (Glu) via gastrostomy, and after 4 days a 30% full-thickness burn was made. Before and after administration of the burn, we measured serum cytokines; amounts of bacteria in the mesenteric lymph node (MLN), liver, and spleen (estimation of BT); mucosal thickness of the terminal ileum; and body weight changes. To confirm the effectiveness of MA in the small intestine, we estimated succinyl-CoA:3-oxoacid CoA-transferase (SCOT) expression in the terminal ileum by immunohistochemical staining and Western blot analysis. RESULTS: At 6 hours after burn, all cytokines were lower, and BT in the MLN was inhibited significantly in the MA group. Ileal mucosal thickness was not significantly different, but mucosa was more edematous in the Glu group. At 3 days after burn injury, BT was significantly inhibited in the MLN and liver, and the ileal mucosa was significantly thicker in the MA group. Body weight loss after burn injury was significantly smaller in the MA group. SCOT expression was the strongest at 6 hours after burn injury by Western blot analysis but not by immunohistochemical staining. CONCLUSIONS: Enteral nutrition of MA may be useful for the inhibition of intestinal mucosal atrophy and the prevention of multiple organ dysfunction syndrome caused by the inhibition of BT and subsequent overproduction of cytokines.

Acetoacetates↗