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Hideaki Morita,
Ichiro Nomura,
Kanami Orihara,
Koichi Yoshida,
Akira Akasawa,
Hiroshi Tachimoto, Yoshikazu Ohtsuka,
Yoshiyuki Namai,
Masaki Futamura,
Tetsuo Shoda,
Akio Matsuda,
Norio Kamemura,
Hiroshi Kido,
Takao Takahashi,
Yukihiro Ohya,
Hirohisa Saito,
Kenji Matsumoto
The Journal of allergy and clinical immunology 10/2012; · 9.17 Impact Factor
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Yosuke Baba,
Keiko Maeda,
Takuya Yashiro,
Eisuke Inage,
Kazumi Kasakura,
Ryuyo Suzuki,
François Niyonsaba,
Mutsuko Hara,
Atsushi Tanabe,
Hideoki Ogawa,
Ko Okumura, Yoshikazu Ohtsuka,
Toshiaki Shimizu,
Chiharu Nishiyama
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ABSTRACT: The IL1RL1/ST2 gene encodes a receptor for IL-33. Signaling from IL1RL1/ST2 induced by IL-33 binding was recently identified as a modulator of the Th2 response. The target cells for IL-33 are restricted in some hematopoietic lineages, including mast cells, basophils, eosinophils, Th2 cells, natural killer cells, and dendritic cells. To clarify the molecular mechanisms of cell type-specific IL1RL1/ST2 expression in mast cells and basophils, transcriptional regulation of the human IL1RL1/ST2 promoter was investigated using the mast cell line LAD2 and the basophilic cell line KU812. Reporter assays suggested that two GATA motifs just upstream of the transcription start site in the ST2 promoter are critical for transcriptional activity. These two GATA motifs possess the capacity to bind GATA1 and GATA2 in EMSA. ChIP assay showed that GATA2, but not GATA1, bound to the ST2 promoter in LAD2 cells and that histone H3 at the ST2 promoter was acetylated in LAD2 cells, whereas binding of GATA1 and GATA2 to the ST2 promoter was detected in KU812 cells. Knockdown of GATA2 mRNA by siRNA reduced ST2 mRNA levels in KU812 and LAD2 cells and ST2 protein levels in LAD2 cells; in contrast, GATA1 siRNA transfection up-regulated ST2 mRNA levels in KU812 cells. The ST2 promoter was transactivated by GATA2 and repressed by GATA1 in coexpression analysis. When these siRNAs were introduced into human peripheral blood basophils, GATA2 siRNA reduced ST2 mRNA, whereas GATA1 siRNA up-regulated ST2 mRNA. These results indicate that GATA2 and GATA1 positively and negatively control human ST2 gene transcription, respectively.
Journal of Biological Chemistry 08/2012; 287(39):32689-96. · 4.77 Impact Factor
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Yosuke Baba,
Keiko Maeda,
Takuya Yashiro,
Eisuke Inage,
François Niyonsaba,
Mutsuko Hara,
Ryuyo Suzuki, Yoshikazu Ohtsuka,
Toshiaki Shimizu,
Hideoki Ogawa,
Ko Okumura,
Chiharu Nishiyama
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ABSTRACT: The human IL1RL1/ST2 gene encodes IL33 receptor. Recently, IL33 has been recognized as a key molecule for the development of Th2 response. Although mast cells and basophils are major targets of IL33 and play important roles in IL33-mediated Th2-type immune responses, the expression mechanism of ST2 in mast cells and basophils is largely unknown. In the present study, we analyzed regulation mechanism of the human ST2 promoter in the human mast cell line LAD2 and basophilic cell line KU812.
Promoter activity was determined by reporter assay with plasmids carrying the wild-type ST2 promoter obtained from human genomic DNA and its mutant. The transcription factor binding to the identified cis-element was identified by an electrophoretic mobility shift assay (EMSA). The effect of candidate transcription factor on ST2 expression was confirmed by analyzing ST2 mRNA level in siRNA-introduced cells.
Reporter assay demonstrated that a cis-element of typical Ets-family binding sequence was critical for promoter activity in LAD2 and KU812. An Ets-family transcription factor PU.1 bound to this element in an EMSA. When PU.1 expression was suppressed by siRNA, ST2 mRNA level was significantly reduced in KU812.
These observations indicated that PU.1 positively regulates the ST2 promoter as a transcription factor that directly transactivates the ST2 promoter via Ets-family-related cis-element in mast cells and basophils.
Allergology International 07/2012; 61(3):461-7.
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ABSTRACT: Ribavirin-related anemia is a serious side-effect of the pegylated interferon and ribavirin therapy used for hepatitis C, and may be cause for a reduction in ribavirin dose or even cessation of treatment. The aim of this study was to evaluate the prophylactic effects of oral eicosapentaenoic acid (EPA) supplementation on ribavirin-induced hemolytic anemia in pediatric and young adult patients.
Twelve chronic hepatitis C patients ranging in age from 3 to 21 years (mean, 13.9 ± 5.1 years) who received pegylated interferon α-2b and ribavirin combination therapy were randomized to either the control group (n = 6) or EPA group (n = 6). Blood samples were collected before, and at 4, 8, and 16 weeks after treatment to measure clinical laboratory parameters.
The reduction in hemoglobin levels of the EPA group was significantly ameliorated at 8 and 16 weeks when compared to the control group (P < 0.05). There was no significant difference in plasma ribavirin concentrations between the two groups during the treatment. However, one patient in the control group had a reduction in ribavirin dose.
EPA supplementation prevented ribavirin-induced hemolytic anemia during combination therapy with pegylated interferon α-2b and ribavirin in pediatric and young adult patients.
Pediatrics International 02/2012; 54(4):528-31. · 0.63 Impact Factor
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The Journal of allergy and clinical immunology 02/2012; 129(6):1676-8. · 9.17 Impact Factor
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ABSTRACT: Although initial infection with Helicobacter pylori may occur before 5 years of age, the pediatric mucosal immune response against H. pylori is not clear. The aim of the present study was to evaluate immune responses in the H. pylori-infected gastric mucosa of children using microarray and real-time polymerase chain reaction (PCR) analysis of pediatric gastric samples.
Gastric samples were obtained from 12 patients undergoing routine endoscopy of chronic abdominal complaints. Six patients (three boys, three girls) aged 10.1-14.6 years had evidence of H. pylori infection, and the remaining six (three boys, three girls) aged 10.3-15.5 years had no evidence of infection and presented no histological changes associated with gastritis. Microarray and real-time PCR analyses were performed, and the changes in gene expression-related immune response were also analyzed.
Using microarray analysis, the total number of significantly upregulated and downregulated genes (fold change >5, P < 0.01) was 21 in the antrum and 16 in the corpus when comparing patients with or without infection. Using real-time PCR, the expression of lipocalin-2 (Lcn2), C-C motif chemokine ligand (CCL) 18, C-X-C motif chemokine ligand (CXCL) 9 and CXCL11 was upregulated, while the expression of pepsinogen (PG) I and PGII was downregulated when comparing patients with or without infection.
Lcn2, CCL18, CXCL9, CXCL11, PGI and PGII play important roles in childhood H. pylori infection.
Pediatrics International 02/2012; 54(3):319-24. · 0.63 Impact Factor
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ABSTRACT: To examine the immune-modulatory effects of probiotics during early infancy, Bifidobacterium breve M-16V (B. breve) was administered to rat pups during the newborn or weaning period, and the expression of inflammatory genes was investigated using a cDNA microarray and real-time PCR.
After B. breve administration, significant increases in the numbers of Bifidobacterium in both the cecum and colon were confirmed during the newborn period. The numbers of upregulated and downregulated genes were greater during the weaning period than in the newborn period and were greatest in the colon, with fewer genes altered in the small intestine and the fewest in the spleen. The expression of inflammation-related genes, including lipoprotein lipase (Lpl), glutathione peroxidase 2 (Gpx2), and lipopolysaccharide-binding protein (Lbp), was significantly reduced in the colon during the newborn period. In weaning rat pups, the expression of CD3d, a cell surface receptor-linked signaling molecule, was significantly enhanced in the colon; however, the expression of co-stimulatory molecules was not enhanced.
Our findings support a possible role for B. breve in mediating anti-inflammatory and antiallergic reactions by modulating the expression of inflammatory molecules during the newborn period and by regulating the expression of co-stimulatory molecules during the weaning period.
Gene expression in the intestine was investigated after feeding 5 × 10(8) cfu of B. breve every day to the F344/Du rat from days 1 to 14 (newborn group) and from days 21 to 34 (weaning group). mRNA was extracted from intestine, and the expression of inflammatory gene was analyzed by microarray and real-time PCR.
Pediatric Research 01/2012; 71(1):46-53. · 2.70 Impact Factor
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ABSTRACT: Corticosteroids therapy, classically the first-line treatment for ulcerative colitis (UC), often causes serious side-effects. Theoretically, pulse steroid therapy where high doses are given for a shorter period may have maximal beneficial effects and minimal side-effects as induction therapy for UC. We have therefore retrospectively compared induction therapy using pulse steroids with conventional steroid treatment for children and adolescents with moderate-to-severe UC.
We utilized conventional steroid treatment (prednisolone 1-1.5 mg/kg/day) as an induction treatment in 17 UC patients between 1985 and 2006. Alternatively we used a 3-day megadose pulse steroid therapy (methylprednisolone intravenously 20-30 mg/kg/day, max. 1000 mg/day) in 20 UC patients from 1993 to 2006.
Pulse steroid therapy successfully induced rapid remission in UC patients with moderate-to-severe disease compared with conventional treatment (13.2 days vs 25.1 days; P < 0.05). The amelioration of Pediatric Ulcerative Colitis Activity Index score between before and 1 week after pulse steroid therapy was significantly more than that of conventional treatment (P < 0.01). No serious adverse effects were observed in the patients treated with pulse steroid therapy. However, the rate of the relapse episodes during the next 12 months after pulse steroid therapy was not significantly different from that after conventional treatment.
These findings suggest that pulse steroid therapy is an option to be considered in children with moderate-to-severe UC.
Pediatrics International 05/2011; 53(6):974-9. · 0.63 Impact Factor
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Ichiro Nomura,
Hideaki Morita,
Shinichi Hosokawa,
Hiroaki Hoshina,
Tatsuki Fukuie,
Misa Watanabe, Yoshikazu Ohtsuka,
Tetsuo Shoda,
Akihiko Terada,
Tetsuya Takamasu,
Katsuhiro Arai,
Yushi Ito,
Yukihiro Ohya,
Hirohisa Saito,
Kenji Matsumoto
The Journal of allergy and clinical immunology 03/2011; 127(3):685-8.e1-8. · 9.17 Impact Factor
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Yoshikazu Ohtsuka,
Kyo Okada,
Yoko Yamakawa,
Tamaki Ikuse,
Yosuke Baba,
Eisuke Inage,
Tohru Fujii,
Hirohisa Izumi,
Kyoichi Oshida,
Satoru Nagata,
Yuichiro Yamashiro,
Toshiaki Shimizu
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ABSTRACT: Necrotizing enterocolitis (NEC) is a devastating intestinal disease of premature infants. Although ω-3 fatty acids are known to have antiinflammatory effects, their effect against NEC remains unclear.
Mother rats fed a soybean-based, docosahexaenoic acid (DHA)- or eicosapentaenoic acid (EPA)-enriched diet from days 7 to 20 of gestation were examined. On day 20, the rat pups were delivered by abdominal incision, their intestines were removed, and messenger RNA was extracted. A rat NEC model was used to confirm the effects of ω-3 fatty acids on the inflamed intestine (n = 20-28). The expression of inflammatory molecules was analyzed by real-time polymerase chain reaction (n = 11-14).
The concentrations of DHA and EPA in the intestine were significantly increased in the DHA and EPA groups (P < .01). The expression of the antiinflammatory prostaglandin E2 receptor EP3 was increased in the DHA (P < .05) and EPA groups (P < .01). In the NEC model, the reduced incidence of colitis was confirmed in the DHA and EPA groups. The expression of peroxisome proliferator-activated receptor γ was increased (P < .05), and the inhibitor of nuclear factor-κB α/β decreased in both the DHA (P < .01) and EPA groups (P < .05).
Our findings indicate that ω-3 fatty acids are beneficial for protecting the premature intestine from inflammation by regulating eicosanoid- and nuclear factor-κB-related metabolite expression.
Journal of Pediatric Surgery 03/2011; 46(3):489-95. · 1.45 Impact Factor
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ABSTRACT: The objective of this study was to compare the gastric acidity patterns of patients with duodenal ulcers and| normal children. Eight patients with duodenal ulcer had their intragastric pH monitored for two consecutive 24 h periods using intragastric glass electrodes. The first 24 h period elucidated pH patterns in the absence of treatment and the second period evaluated the acid suppressive effect of 15 mg/kg of cimetidine when given in three divided doses. Results showed that the ulcer patients were hyperacidic, particularly at midnight. This finding was in marked contrast to the results obtained in the study of normal controls. The mean pH of normal children was above 3 around midnight. This phenomenon is known as intragastric pH inversion. The mean pH 3 time (the cumulative duration of the time for which gastric pH is maintained at ≥ pH 3) was significantly shorter in patients with ulcers. However, pH 3 time of these patients significantly increased throughout the 24 h recording period during the daytime and at night after the introduction of cimetidine. This resulted in an induction of apparent nocturnal intragastric pH inversion for the ulcer patients. This study demonstrates the usefulness of 24 h continuous intragastric pH monitoring in children. The data showed that there was a pattern of gastric hyperacidity in pediatric ulcer patients which is clearly distinct from that of normal children, particularly in the patterns occurring at midnight. Cimetidine at 15 mg/kg per day in three divided doses was effective in suppressing secretion even at night.
Pediatrics International 01/2011; 37(5):557 - 561. · 0.63 Impact Factor
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ABSTRACT: Although cyclosporine (CsA) therapy is effective in the management of children with steroid-dependent nephrotic syndrome (SDNS), a recent study has revealed that the use of CsA itself was a significant predictor of NS relapse in adulthood. The efficacy of single daily high-dose mizoribine (MZR) therapy was assessed in 10 children with SDNS (mean age, 6.2 years) who had never been treated with CsA previously. MZR was started at 5 mg/kg, administered as a single daily dose after breakfast, and the dose was adjusted to achieve 2-h post-dose MZR levels (C2) of approximately 3 μg/ml. In 9 of the 10 patients, treatment with a single daily dose of MZR (mean dose, 8.4 mg/kg/day) over a period of 22 months (median) resulted in significant reduction of the mean prednisolone dose from 0.39 to 0.15 mg/kg/day and the median 12-month relapse rate from 3.0 to 0.4 episodes/12 months. Although cyclophosphamide was initiated in one patient because of treatment failure, none of the 10 patients required treatment with CsA during the observation period (median, 33 months). These data indicate that single daily high-dose MZR therapy is possibly useful in treating children with SDNS and that it may also eliminate the need for CsA in some patients.
Pediatric Nephrology 12/2010; 26(3):479-83. · 2.52 Impact Factor
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ABSTRACT: Previous studies suggest the homeostasis between acquisition of tolerance to the indigenous microflora and protective immune responses appears to be disrupted in inflammatory bowel disease (IBD). Some experimental studies indicate peroxisome proliferator-activated receptor γ (PPARγ) has been implicated as a regulator of intestinal inflammatory responses. In addition, the toll-like receptor (TLR)-4 can regulate expression of PPARγ in colonic epithelial cells. We attempted to demonstrate whether the functional imbalance between TLRs and PPARγ could lead to the onset and some polymorphisms of those genes could contribute to susceptibility to IBD.
RT-PCR analysis were performed to detect TLR4 and PPARγ mRNA associated with those of P65 of NFκB, TNFα, MyD88, NOD2/CARD15, TLR-2,5,9, in the diseased colonic mucosa in ulcerative colitis (UC; n = 13) and Crohn's disease (CD; n = 7) compared with normal controls (n = 18). Consequently, we genotyped UC (n = 29) and CD (n = 10) compared with normal controls (n = 134) for the prevalence of suspicious mutations.
In a subset of UC patients who were revealed to carry PPARγ Pro12Ala mutation later, impaired expression of normal PPARγ mRNA was noted in the diseased mucosa accompanied with upregulations of MyD88 TLR-4, 5, 9, P65 and TNFα in mRNA levels. The prevalence of PPARγ Pro12Ala mutation was more frequently found in UC patients compared with CD patients and normal controls (P < 0.05).
These findings suggested that imbalances between TLRs and PPARγ in response to luminal bacteria could lead to colonic inflammation in some UC patients. Alternative explanations will be needed for the onset of the rest of UC and CD.
Pediatrics International 10/2010; 52(5):729-34. · 0.63 Impact Factor
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Yoshikazu Ohtsuka,
Katsuhiro Arai,
Yo Aoyagi,
Tohru Fujii,
Yoko Yamakawa,
Kiyotaka Ohtani,
Tamaki Ikuse,
Yosuke Baba,
Eisuke Inage,
Takahiro Kudo,
Ryuyo Suzuki,
Satoru Nagata,
Toshiaki Shimizu
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ABSTRACT: 6-Mercaptopurine (6-MP) and azathioprine (AZA) are widely used as maintenance therapy in children with inflammatory bowel disease (IBD). However, proper 6-thioguanine nucleotide (6-TGN) concentrations in Japanese children with IBD have not been reported.
This retrospective review examines 32 ulcerative colitis (UC) patients and 19 Crohn's disease (CD) patients (12.87 ± 3.56 years) who required 6-MP or AZA to maintain disease remission. All patients were treated with 6-MP or AZA for at least 3 weeks prior to this study in addition to previous treatment. 6-MP dose, 6-TGN levels, assayed by high-performance liquid chromatography, as well as laboratory data were evaluated.
Thirty-five children were successfully kept in remission with 6-MP and AZA therapy after weaning off corticosteroids. Overall, 123 measurements (59 active disease, 64 in remission) were analyzed. The mean 6-TGN concentration of the entire study population was 499.61 ± 249.35 pmol/8 × 10(8) red blood cell. The mean 6-MP dose in patients with active disease (0.910 ± 0.326 mg/kg per day) was significantly higher than for patients in remission (0.749 ± 0.225) (P = 0.0016). A significant inverse correlation was found between white blood cell counts and 6-TGN concentrations (r = 0.275, P < 0.002). Two patients experienced leukopenia with alopecia, and four transiently experienced increased serum levels of pancreatic enzymes, although no thiopurine S-methyl transferase mutations were confirmed.
The doses of 6-MP or AZA needed to maintain remission in Japanese children with IBD are lower than those reported in Western countries. However, 6-TGN concentrations in this population are higher than previously reported.
Journal of Gastroenterology and Hepatology 10/2010; 25(10):1626-30. · 2.87 Impact Factor
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ABSTRACT: It remains controversial whether Kawasaki disease (KD) is a risk factor for the onset of atherosclerosis. An imbalance of peroxisome proliferator-activated receptor γ (PPARγ) and adiponectin appears to play a role in the onset of atherosclerosis in adults, and we therefore examined PPARγ mRNA expression and adiponectin profiles in the peripheral white blood cells obtained from KD patients.
A total of 50 subjects were studied: nine patients with acute KD, 20 patients with convalescent KD, and 21 age-matched controls. The gene expression of PPARγ, monocyte chemoattractant protein-1, and CC chemokine receptor 2 present in the blood were quantified. The relative gene expression, adiponectin levels, and the three adiponectin isoforms were compared among the subjects.
The abundance of PPARγ and CC chemokine receptor 2 mRNA was significantly increased in convalescent KD patients. The monocyte chemoattractant protein-1 level was also increased in convalescent KD patients. The level of high-molecular-weight adiponectin was significantly lower in convalescent patients compared to controls. The PPARγ transcription levels negatively correlated with apolipoprotein A-I levels in acute KD patients.
The transcript abundance of PPARγ and low levels of high-molecular-weight adiponectin in KD patients may have important clinical implications on the development of premature atherosclerosis. Because the potential risk for developing atherosclerosis has not yet been verified, long-term observation is important, even in convalescent KD patients without coronary artery lesions.
Pediatrics International 10/2010; 52(5):795-800. · 0.63 Impact Factor
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ABSTRACT: Serum pro-inflammatory cytokine levels are frequently elevated in the acute phase of pediatric inflammatory bowel disease (IBD). Because the role of pro-inflammatory cytokine in the acute phase of pediatric IBD has not been well investigated, the serum levels of pro-inflammatory cytokines and the expression of Th1 and Th2 signaling molecules in mucosa from the acute phase of pediatric IBD were examined.
Twenty children with ulcerative colitis (UC; mean age, 9.95 ± 4.10 years) and 12 with Crohn's disease (CD; mean age, 10.0 ± 4.90 years) were enrolled for the serum cytokine (interleukin [IL]-4, IL-5, IL-6, tumor necrosis factor-α, tumor growth factor-β1, and interferon-γ) assay. Expression of T-helper cell 1 (Th1) (T-box expressed in T cells: T-bet and signal transducer and activator of transcription-4: STAT-4) and Th2 (GATA-3 and STAT-6) signaling molecules was examined on real-time polymerase chain reaction using mucosal samples from eight children in the acute phase of UC, eight with CD and eight controls.
Significant elevation of serum IL-4 and IL-6 levels was detected at the acute phase of pediatric UC and CD compared with levels at remission (P < 0.05 in each). The mucosal expression of GATA-3 and STAT-4 was significantly enhanced in the acute phase of pediatric UC compared with normal mucosa. No significant difference was observed in the expression of all examined molecules in the acute phase of pediatric CD.
IL-4 and its signaling molecule GATA-3, as well as the Th1 signaling molecule STAT-4, are involved in the pathogenesis of acute phase of pediatric UC.
Pediatrics International 08/2010; 52(4):584-9. · 0.63 Impact Factor
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Journal of pediatric gastroenterology and nutrition 07/2010; 51(1):96-9. · 2.18 Impact Factor
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Pediatrics International 04/2010; 52(2):335-6. · 0.63 Impact Factor
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Pediatrics International 02/2010; 52(1):e43-5. · 0.63 Impact Factor
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Pediatrics International 02/2010; 52(1):e57-9. · 0.63 Impact Factor
