83 results on '"Shunsaku Nakagawa"'
Search Results
52. Identification of Biomarkers for Tubular Injury and Interstitial Fibrosis in Chronic Kidney Disease
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Shunsaku Nakagawa
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0301 basic medicine ,Inflammasomes ,Interleukin-1beta ,030232 urology & nephrology ,Gene Expression ,Pharmaceutical Science ,Nephron ,Kidney ,Proinflammatory cytokine ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Renal Insufficiency, Chronic ,Myofibroblasts ,Pharmacology ,urogenital system ,business.industry ,Interleukin-18 ,medicine.disease ,IRAK4 ,Fibrosis ,Toll-Like Receptor 2 ,Up-Regulation ,Toll-Like Receptor 4 ,Interleukin-1 Receptor-Associated Kinases ,Kidney Tubules ,030104 developmental biology ,medicine.anatomical_structure ,Myeloid Differentiation Factor 88 ,Cancer research ,Tubulointerstitial fibrosis ,Pericyte ,Pericytes ,business ,Myofibroblast ,Biomarkers ,Signal Transduction ,Kidney disease - Abstract
In chronic kidney disease (CKD), progressive nephron loss causes tubulointerstitial fibrosis and progressive tubular injury. Recent identification of the major cell populations of myofibroblast precursors in the kidney has enabled us to dissect the fibrogenic process after tubular injury. Kidney pericytes are a possible precursor of myofibroblasts, and may be promising targets for treating fibrogenesis. Our recent studies have shown that pericytes activate Toll-like receptor (TLR) 2/4- and myeloid differentiation primary response 88 (MyD88)-dependent proinflammatory signaling in response to renal tubular injury. We also found active roles of inflammasomes in kidney pericytes, leading to interleukin (IL)-1β and IL-18 secretion. Genetic ablation of MyD88 in pericytes, or pharmacological inhibition of MyD88 signaling by an IL-1 receptor-associated kinase 4 (IRAK4) inhibitor, halted interstitial fibrosis after renal tubular injury. Our data indicate that pericytes not only contribute to interstitial fibrosis by aberrant wound-healing responses, but also serve as innate immune surveillance cells that regulate the inflammatory process, exacerbating tubular injury by the release of cytokines and chemokines. On the other hand, our recent study using a microarray analysis aimed to identify molecular changes that reflected the histopathological progression of renal tubulointerstitial fibrosis and tubular cell damage in patients with CKD. The results indicated that 5 genes were up-regulated in the kidney of CKD patients, and that their expression levels correlated with the extent of tubulointerstitial fibrosis and tubular cell injury. These findings provide important information for the development of diagnostic tools and therapeutic agents for predicting and preventing progressive renal disease.
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- 2017
53. Taxanes and platinum derivatives impair Schwann cells via distinct mechanisms
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Shuji Wakatsuki, Takashi Ogihara, Tomohiro Omura, Atsushi Yonezawa, Yui Nakazato, Mayuna Matsumoto, Satoshi Imai, Shunsaku Nakagawa, Kazuo Matsubara, Madoka Koyanagi, Takayuki Nakagawa, Ziauddin Azimi, Shuji Kaneko, and Toshiyuki Araki
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0301 basic medicine ,Galectin 3 ,Receptor, Nerve Growth Factor ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Dorsal root ganglion ,Ganglia, Spinal ,Cells, Cultured ,Myelin Sheath ,Neurons ,Multidisciplinary ,biology ,Chemistry ,Anatomy ,Sciatic Nerve ,Schwann cell ,Cell biology ,Mitochondria ,Oxaliplatin ,medicine.anatomical_structure ,Paclitaxel ,Medicine ,Taxoids ,Sciatic nerve ,medicine.drug ,Cell Survival ,Science ,Antineoplastic Agents ,Article ,03 medical and health sciences ,medicine ,Animals ,Cell Shape ,Platinum ,Cisplatin ,Neurotoxicity ,Cell Dedifferentiation ,medicine.disease ,Coculture Techniques ,Myelin basic protein ,Rats ,030104 developmental biology ,Peripheral neuropathy ,nervous system ,biology.protein ,Schwann Cells ,Somatic system ,030217 neurology & neurosurgery - Abstract
Impairment of peripheral neurons by anti-cancer agents, including taxanes and platinum derivatives, has been considered to be a major cause of chemotherapy-induced peripheral neuropathy (CIPN), however, the precise underlying mechanisms are not fully understood. Here, we examined the direct effects of anti-cancer agents on Schwann cells. Exposure of primary cultured rat Schwann cells to paclitaxel (0.01 μM), cisplatin (1 μM), or oxaliplatin (3 μM) for 48 h induced cytotoxicity and reduced myelin basic protein expression at concentrations lower than those required to induce neurotoxicity in cultured rat dorsal root ganglion (DRG) neurons. Similarly, these anti-cancer drugs disrupted myelin formation in Schwann cell/DRG neuron co-cultures without affecting nerve axons. Cisplatin and oxaliplatin, but not paclitaxel, caused mitochondrial dysfunction in cultured Schwann cells. By contrast, paclitaxel led to dedifferentiation of Schwann cells into an immature state, characterized by increased expression of p75 and galectin-3. Consistent with in vitro findings, repeated injection of paclitaxel increased expression of p75 and galectin-3 in Schwann cells within the mouse sciatic nerve. These results suggest that taxanes and platinum derivatives impair Schwan cells by inducing dedifferentiation and mitochondrial dysfunction, respectively, which may be important in the development of CIPN in conjunction with their direct impairment in peripheral neurons.
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- 2017
54. Pericyte MyD88 and IRAK4 control inflammatory and fibrotic responses to tissue injury
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Jeremy S. Duffield, Jin Joo Cha, Irina A. Leaf, Ivan G. Gomez, Kristen Mittelsteadt, Bryce G. Johnson, William A. Altemeier, Kevin Guckian, and Shunsaku Nakagawa
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0301 basic medicine ,Interleukin-1beta ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,Fibrosis ,medicine ,Animals ,Humans ,Myofibroblasts ,Cells, Cultured ,Mice, Knockout ,Chemistry ,Regeneration (biology) ,Inflammasome ,General Medicine ,Acute Kidney Injury ,medicine.disease ,IRAK4 ,Cell biology ,TLR2 ,Interleukin-1 Receptor-Associated Kinases ,030104 developmental biology ,medicine.anatomical_structure ,Myeloid Differentiation Factor 88 ,Pericyte ,Pericytes ,Myofibroblast ,Signal Transduction ,medicine.drug - Abstract
Fibrotic disease is associated with matrix deposition that results in the loss of organ function. Pericytes, the precursors of myofibroblasts, are a source of pathological matrix collagens and may be promising targets for treating fibrogenesis. Here, we have shown that pericytes activate a TLR2/4- and MyD88-dependent proinflammatory program in response to tissue injury. Similarly to classic immune cells, pericytes activate the NLRP3 inflammasome, leading to IL-1β and IL-18 secretion. Released IL-1β signals through pericyte MyD88 to amplify this response. Unexpectedly, we found that MyD88 and its downstream effector kinase IRAK4 intrinsically control pericyte migration and conversion to myofibroblasts. Specific ablation of MyD88 in pericytes or pharmacological inhibition of MyD88 signaling by an IRAK4 inhibitor in vivo protected against kidney injury by profoundly attenuating tissue injury, activation, and differentiation of myofibroblasts. Our data show that in pericytes, MyD88 and IRAK4 are key regulators of 2 major injury responses: inflammatory and fibrogenic. Moreover, these findings suggest that disruption of this MyD88-dependent pathway in pericytes might be a potential therapeutic approach to inhibit fibrogenesis and promote regeneration.
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- 2016
55. Concentration and Glycoform of Rituximab in Plasma of Patients with B Cell Non-Hodgkin’s Lymphoma
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Kazuo Matsubara, Sho Masui, Yuki Otani, Masaya Denda, Masahiro Tsuda, Tomohiro Omura, Toshiyuki Kitano, Atushi Yonezawa, Mayuko Mori, Ikuko Yano, Shunsaku Nakagawa, Yuki Sato, Takayuki Nakagawa, Makoto Hayakari, Yasuaki Ikemi, Akifumi Takaori-Kondo, Yui Isomoto, and Satoshi Imai
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Adult ,Male ,Protein Conformation ,Pharmaceutical Science ,Antineoplastic Agents ,02 engineering and technology ,Pharmacology ,030226 pharmacology & pharmacy ,Plasma ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,immune system diseases ,hemic and lymphatic diseases ,Humans ,Medicine ,Pharmacology (medical) ,B cell ,Aged ,Glycoproteins ,B-Lymphocytes ,biology ,business.industry ,Lymphoma, Non-Hodgkin ,Organic Chemistry ,Middle Aged ,021001 nanoscience & nanotechnology ,medicine.disease ,Lymphoma ,Non-Hodgkin's lymphoma ,medicine.anatomical_structure ,Pharmacodynamics ,Plasma concentration ,biology.protein ,Molecular Medicine ,Female ,Rituximab ,Antibody ,0210 nano-technology ,business ,Biotechnology ,medicine.drug - Abstract
Therapeutic antibodies have heterogeneities in their structures, although its structural alteration in the body is unclear. Here, we analyzed the change of amino acid modifications and carbohydrate chains of rituximab after administration to patients. Twenty B cell non-Hodgkin’s lymphoma patients who were treated with rituximab for the first time or after more than one year’s abstinence were recruited. Structural analysis of rituximab was carried out at 1 h after administration and at the trough by using liquid chromatography/time-of-flight-mass spectrometry. Plasma rituximab concentration and pharmacodynamic markers were also determined. Of recruited twenty, 3 patients exhibited rapid rituximab clearance. Nine types of carbohydrate chains were detected in rituximab isolated from the blood. The composition ratios in some glycoforms were significantly different between at 1 h after administration and at the trough, although consisted amino acids remained unchanged. The patients with high clearance showed extensive alterations of glycoform composition ratios. However, pharmacodynamics makers were not different. Inter-individual variations in plasma concentrations of rituximab were found in some B-NHL patients. We could analyze a change in glycoforms of rituximab in the patients, and this finding may affect the pharmacokinetics of rituximab.
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- 2019
56. Qualitative Component Analysis of Filgrastim Biosimilars by LC/QTOF-MS
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Kengo Matsumura, Tomohiro Omura, Takayuki Nakagawa, Yasuaki Ikemi, Atsushi Yonezawa, Yuki Otani, Satoshi Imai, Kazuo Matsubara, Ikuko Yano, Tatsuhiro Yoshiki, Masahiro Tsuda, and Shunsaku Nakagawa
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0301 basic medicine ,03 medical and health sciences ,030104 developmental biology ,Qualitative analysis ,Chromatography ,Chemistry ,medicine ,Biosimilar ,Filgrastim ,medicine.drug - Published
- 2016
57. Ubiquitin ligase HMG-CoA reductase degradation 1 (HRD1) prevents cell death in a cellular model of Parkinson's disease
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Tomohiro Omura, Hiroki Matsuda, Kazuo Matsubara, Luna Nomura, Ikuko Yano, Masaya Denda, Satoshi Imai, Takayuki Nakagawa, Shunsaku Nakagawa, and Atsushi Yonezawa
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0301 basic medicine ,Programmed cell death ,Cell Survival ,Ubiquitin-Protein Ligases ,Biophysics ,Biochemistry ,Models, Biological ,Parkin ,03 medical and health sciences ,0302 clinical medicine ,Cell Line, Tumor ,Humans ,RNA, Small Interfering ,Oxidopamine ,Molecular Biology ,Gene knockdown ,biology ,Cell Death ,Chemistry ,Endoplasmic reticulum ,Proteins ,Parkinson Disease ,Cell Biology ,Endoplasmic Reticulum Stress ,Ubiquitin ligase ,Cell biology ,030104 developmental biology ,biology.protein ,Unfolded protein response ,Cellular model ,030217 neurology & neurosurgery ,Intracellular - Abstract
Endoplasmic reticulum (ER) stress may play a role in the etiology of Parkinson's disease (PD). We have previously reported that ubiquitin ligase 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase degradation 1 (HRD1) involved in ER stress degrades unfolded protein that accumulates in the ER due to loss of function of Parkin, which is a causative factor in familial PD. We have also demonstrated that cell death is suppressed by the degradation of unfolded proteins. These findings indicate that HRD1 may serve as a compensatory mechanism for the loss of function of Parkin in familial PD patients. However, the role of HRD1 in sporadic PD has not yet been identified. This study aimed to reveal the roles of HRD1 and associated molecules in a cellular model of PD. We demonstrated that expressions of HRD1 and Suppressor/Enhancer Lin12 1-like (SEL1L: a HRD1 stabilizer) increased in SH-SY5Y human neuroblastoma cells upon exposure to 6-hydroxydopamine (6-OHDA). The 6-OHDA-induced cell death was suppressed in cells overexpressing wt-HRD1, whereas cell death was enhanced in cells with knockdown of HRD1 expression. These results suggest that HRD1 is a key molecule involved in 6-OHDA-induced cell death. By contrast, suppression of SEL1L expression decreased the amount of HRD1 protein. As a result, 6-OHDA-induced cell death was enhanced in cells suppressing SEL1L expression, and this cell death was much more evident than that in cells with suppression of HRD1 expression. These findings strongly indicate that SEL1L is necessary for maintaining and stabilizing the amount of HRD1 protein, and stabilizing the amount of HRD1 protein through SEL1L may serve to protect against 6-OHDA-induced cell death. Furthermore, the expression of Parkin was reinforced when HRD1 mRNA had been suppressed in cells, but was not observed when SEL1L mRNA had been restrained. It is possible that Parkin expression is induced as a compensatory mechanism when HRD1 mRNA decreases. This intracellular transduction may suppress the enhancement of 6-OHDA-induced cell death caused by the loss of HRD1. Taken together with these results, it is suggested that HRD1 and its stabilizer (SEL1L) are key molecules for elucidating the pathogenesis and treatment of PD.
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- 2018
58. Effect of medication adherence on disease activity among Japanese patients with rheumatoid arthritis
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Tsuneyo Mimori, Takao Fujii, Kazuo Matsubara, Mayumi Nakaishi, Hirohisa Imai, Atsushi Yonezawa, Takayuki Nakagawa, Satoshi Imai, Shunsaku Nakagawa, Masao Tanaka, Tomohiro Omura, Hiromu Ito, Wataru Yamamoto, Ran Nakashima, and Motomu Hashimoto
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Male ,Questionnaires ,Physical disability ,Arthritis ,lcsh:Medicine ,Aminotransferases ,Disease ,Severity of Illness Index ,Biochemistry ,Arthritis, Rheumatoid ,Cohort Studies ,Disability Evaluation ,0302 clinical medicine ,Medicine and Health Sciences ,030212 general & internal medicine ,lcsh:Science ,skin and connective tissue diseases ,Multidisciplinary ,Pharmaceutics ,Middle Aged ,Hospitals ,Enzymes ,Treatment Outcome ,Research Design ,Rheumatoid arthritis ,Antirheumatic Agents ,Cohort ,Disease Progression ,Female ,Cohort study ,Research Article ,musculoskeletal diseases ,Adult ,medicine.medical_specialty ,Patients ,Immunology ,Rheumatoid Arthritis ,Research and Analysis Methods ,Medication Adherence ,Autoimmune Diseases ,03 medical and health sciences ,Rheumatology ,Adverse Reactions ,Drug Therapy ,Transferases ,Internal medicine ,Severity of illness ,medicine ,Humans ,Aged ,030203 arthritis & rheumatology ,Pharmacology ,Survey Research ,business.industry ,lcsh:R ,Biology and Life Sciences ,Proteins ,medicine.disease ,Health Care ,Health Care Facilities ,Enzymology ,lcsh:Q ,Clinical Immunology ,Clinical Medicine ,business - Abstract
For the optimum efficacy of disease-modifying anti-rheumatic drugs (DMARDs), patients need to be adherent to their medication regimen. To clarify the effects of medication adherence on disease activity in Japanese patients with rheumatoid arthritis (RA), we conducted a cohort study in patients with various stages of RA. Patients were enrolled from the Kyoto University RA Management Alliance cohort, and followed up prospectively for 12 months. In this study, a total of 475 patients were analyzed and divided into 9 groups according to their medication adherence and the RA disease duration. The primary outcomes were based on the rate of a disease flare. The secondary outcomes were the changes in disease activity score using 28 joints (DAS28-ESR), simplified disease activity index (SDAI) and physical disability by health assessment questionnaire-disability index (HAQ). The changes in DAS28-ESR, HAQ, and the risk of disease flare in the highly adherent patients were significantly lower than those of the less adherent patients among the groups with RA ≤ 4.6 years but not those among the other groups. Taken together, this study identified a significant association between medication adherence and the disease flare during early-stage RA or short disease duration. These results emphasize the need to pay more attention to medication adherence in preventing the disease progression of RA.
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- 2018
59. Oxicam-derived non-steroidal anti-inflammatory drugs suppress 1-methyl-4-phenyl pyridinium-induced cell death via repression of endoplasmic reticulum stress response and mitochondrial dysfunction in SH-SY5Y cells
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Joe Yamamoto, Kazuo Matsubara, Satoshi Imai, Shunsaku Nakagawa, Atsushi Yonezawa, Tomohiro Omura, Gaia Hashimoto, Yuki Sato, Takayuki Nakagawa, Ikuko Yano, Yoshikazu Tasaki, and Miwa Sasaoka
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0301 basic medicine ,Programmed cell death ,1-Methyl-4-phenylpyridinium ,Mitochondrial Diseases ,Eukaryotic Initiation Factor-2 ,Biophysics ,Meloxicam ,Biochemistry ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cell Line, Tumor ,Humans ,Phosphorylation ,Molecular Biology ,Protein kinase B ,Cell Death ,Endoplasmic reticulum ,Anti-Inflammatory Agents, Non-Steroidal ,Cell Biology ,Tunicamycin ,Endoplasmic Reticulum Stress ,Cell biology ,030104 developmental biology ,chemistry ,Apoptosis ,Unfolded protein response ,Signal transduction ,Proto-Oncogene Proteins c-akt ,030217 neurology & neurosurgery - Abstract
We have previously reported that oxicam-derived non-steroidal anti-inflammatory drugs (oxicam-NSAIDs), including meloxicam, piroxicam and tenoxicam, elicit protective effects against 1-methyl-4-phenyl pyridinium (MPP+)-induced cell death in a fashion independent of cyclooxygenase (COX) inhibition. We have also demonstrated that oxicam-NSAIDs suppress the decrease in phosphorylation of Akt caused by MPP+. The molecular mechanism through which oxicam-NSAIDs provide cytoprotection remains unclear. In this study, we speculated a possibility that endoplasmic reticulum (ER) stress and/or mitochondrial dysfunction, which are both causative factors of Parkinson's disease (PD), may be involved in the neuroprotective mechanism of oxicam-NSAIDs. We demonstrated here that oxicam-NSAIDs suppressed the activation of caspase-3 and cell death caused by MPP+ or ER stress-inducer, tunicamycin, in SH-SY5Y cells. Furthermore, oxicam-NSAIDs suppressed the increases in the ER stress marker CHOP (apoptosis mediator) caused by MPP+ or tunicamycin, beside suppressing eukaryotic initiation factor 2α (eIF2α) phosphorylation and the increase in ATF4 caused by MPP+. Taken together, these results suggest that oxicam-NSAIDs suppress the eIF2α-ATF4-CHOP pathway, one of the three signaling pathways in the ER stress response. Oxicam-NSAIDs suppressed the decrease in mitochondrial membrane potential depolarization caused by MPP+, indicating they also rescue cells from mitochondrial dysfunction. Akt phosphorylation levels were suppressed after the incubation with MPP+, whereas phosphorylation of eIF2α was enhanced. These results suggest that oxicam-NSAIDs prevented eIF2α phosphorylation and mitochondrial dysfunction by maintaining Akt phosphorylation (reduced by MPP+), thereby preventing cell death.
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- 2018
60. Effects of fasting on warfarin sensitivity index in patients undergoing cardiovascular surgery
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Akiko Nishimura, Kenji Minatoya, Hiromi Taue, Shunsaku Nakagawa, Kazuo Matsubara, Atsushi Yonezawa, Kenji Minakata, Satoshi Imai, Tomohiro Omura, Ikuko Yano, Takayuki Nakagawa, Kazuhiro Yamazaki, Yuki Sato, Yoshiki Katada, and Katsuyuki Matsumura
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medicine.drug_class ,Drug Resistance ,Hemorrhage ,030226 pharmacology & pharmacy ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,medicine ,Humans ,heterocyclic compounds ,Pharmacology (medical) ,In patient ,cardiovascular diseases ,030212 general & internal medicine ,International Normalized Ratio ,Adverse effect ,Blood Coagulation ,Aged ,Retrospective Studies ,Pharmacology ,Prothrombin time ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Dietary intake ,Anticoagulant ,Warfarin ,Anticoagulants ,Retrospective cohort study ,General Medicine ,Fasting ,Middle Aged ,Anesthesia ,Prothrombin Time ,Blood Coagulation Tests ,business ,Metabolism, Inborn Errors ,medicine.drug - Abstract
Warfarin shows large inter- and intra-individual variabilities in its pharmacokinetics and pharmacodynamics. Sufficient understanding of factors affecting the response to warfarin is necessary to achieve improved outcomes for warfarin therapy. In this study, we evaluated effects of fasting on the anticoagulant properties of warfarin. We conducted a retrospective observational study involving a total of 58 patients, who received cardiovascular surgeries and subsequent warfarin therapy. The effect of dietary intake on the anticoagulant properties with warfarin was assessed by measurement of the international normalized ratio of prothrombin time (PT-INR): the anticoagulant activities of warfarin were expressed as the warfarin sensitivity index (WSI). Additionally, fluctuations in WSI during the study period were obtained as differences between the maximum and minimum WSI. The maximum PT-INR and WSI values were significantly higher for patients who were fasting for different reasons during the postoperative period than those in the group without reduced dietary intake. The differences between maximum and minimum WSI in the fasting group significantly increased compared with those in the groups with moderate or no reduced dietary intake. Meanwhile, effects of other markers of clinical conditions including the baseline Child-Pugh score and Charlson Comorbidity Index on WSI were not significant. Our results indicate that postoperative fasting was significantly associated with the anticoagulation activity of warfarin. In patients fasting for different reasons during the postoperative period, closer control of PT-INR values and warfarin adjustments may be required to avoid adverse effects such as bleeding in warfarin treatment.
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- 2018
61. FRI0331 Trough concentration of mycophenolic acid correlates with renal function and serum albumin level in japanese patients with sle
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Shuji Akizuki, Ryosuke Hiwa, Ran Nakashima, Motomu Hashimoto, Masato Mori, Tsuneyo Mimori, Koichiro Ohmura, Kosaku Murakami, Masaaki Tanaka, Shunsaku Nakagawa, Nobuo Kuramoto, and Hajime Yoshifuji
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medicine.medical_specialty ,biology ,medicine.diagnostic_test ,business.industry ,Serum albumin ,Renal function ,Mycophenolate ,Trough (economics) ,Gastroenterology ,Mycophenolic acid ,Therapeutic drug monitoring ,Internal medicine ,medicine ,biology.protein ,Prednisolone ,Trough Concentration ,business ,medicine.drug - Abstract
Background Mycophenolate mofetil (MMF) is an immunosuppressant used for treatment of lupus nephritis. MMF is converted to mycophenolic acid (MPA) by esterases, which is the active metabolite with pharmacological activities. A fixed dose of 2–3 g/day is administered as remission induction therapy.1 The usefulness of therapeutic drug monitoring (TDM) of MMF has not been elucidated. Moreover, little is known about the factor that affects the concentration of MPA in Asian patients. Objectives The aim of this study is to investigate the factor that affects the trough concentration of MPA in Japanese patients with SLE. Methods We recruited the SLE cases whose trough concentrations of MPA were measured from 2014 to 2017 at Kyoto University Hospital. When trough concentrations were measured multiple times in each patient with the same dose of MMF, median concentration was used for the analyses. Linear regression analysis was performed to identify the factor that affects the trough concentration of MPA. The association of trough concentration of MPA and adverse effects of MMF was investigated as well. Results Total of 20 cases were recruited and 43 trough concentrations were included for the analyses. The median daily dose of MMF (g) was 1.5 (range; 0.25–3.0) and the median trough concentration of MPA (μg/ml) was 2.0 (range; 0.4–15.0). Linear regression analysis (table 1) revealed that trough concentration of MPA was correlated with daily dose of MMF (p=0.0081, r=0.40, figure 1A), serum albumin level (p=3.3x10–4, r=0.52, figure 1B) and creatinine clearance (p=1.8x10–5, r=−0.60, figure 1C). Daily dose of prednisolone and serum C4 level were correlated with trough concentration of MPA as well, though multicollinearity was found in these two variables and serum albumin or creatinine clearance. Multivariate analysis (table 2) revealed that serum albumin and creatinine clearance were independently associated with trough concentration of MPA (p=6.2x10–4 and 1.6 × 10–5, respectively). Adverse effects of MMF, such as diarrhoea and cytopenia, were not associated with trough concentration of MPA. Conclusions Trough concentration of MPA was correlated with daily dose of MMF, serum albumin level and creatinine clearance. Reference [1] Ann Rheum Dis2012;71:1771–82. Disclosure of Interest None declared
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- 2018
62. Riboflavin Transporters RFVT/SLC52A Mediate Translocation of Riboflavin, Rather than FMN or FAD, across Plasma Membrane
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Atsushi Yonezawa, Satoshi Imai, Hiroki Yoshimatsu, Shunsaku Nakagawa, Yuki Otani, Tomohiro Omura, Kazuo Matsubara, Yoshiaki Yao, Takayuki Nakagawa, and Congyun Jin
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0301 basic medicine ,animal structures ,Flavin Mononucleotide ,Riboflavin ,Pharmaceutical Science ,Flavin mononucleotide ,Flavoprotein ,Flavin group ,Transporter ,Riboflavin kinase ,Transfection ,Receptors, G-Protein-Coupled ,03 medical and health sciences ,chemistry.chemical_compound ,Humans ,heterocyclic compounds ,Pharmacology ,ATP synthase ,biology ,FAD ,digestive, oral, and skin physiology ,Cell Membrane ,food and beverages ,Membrane Transport Proteins ,General Medicine ,Protein Transport ,030104 developmental biology ,HEK293 Cells ,Biochemistry ,chemistry ,biology.protein ,Flavin-Adenine Dinucleotide ,Efflux ,human activities ,Vitamin B2 - Abstract
Riboflavin (vitamin B2) plays a role in various biochemical oxidation-reduction reactions. Flavin mononucleotide (FMN) and FAD, the biologically active forms, are made from riboflavin. Riboflavin transporters (RFVTs), RFVT1-3/Slc52a1-3, have been identified. However, the roles of human (h)RFVTs in FMN and FAD homeostasis have not yet been fully clarified. In this study, we assessed the contribution of each hRFVT to riboflavin, FMN and FAD uptake and efflux using in vitro studies. The transfection of hRFVTs increased cellular riboflavin concentrations. The uptake of riboflavin by human embryonic kidney cells transfected with hRFVTs was significantly increased, and the efflux was accelerated in a time-dependent manner. However, the uptake and efflux of FMN and FAD hardly changed. These results strongly suggest that riboflavin, rather than FMN or FAD, passes through plasma membranes via hRFVTs. Our findings could suggest that hRFVTs are involved in riboflavin homeostasis in the cells, and that FMN and FAD concentrations are regulated by riboflavin kinase and FAD synthase.
- Published
- 2017
63. Chemotherapy for primary mediastinal yolk sac tumor in a patient undergoing chronic hemodialysis: a case report
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Haruki Hirakawa, Shinya Kimura, Kazuo Matsubara, Naoko Sueoka-Aragane, Tomomi Nakamura, Chiho Nakashima, Taro Funakoshi, Takahiro Horimatsu, Shunsaku Nakagawa, Manabu Muto, and Masanori Masuda
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Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,medicine.medical_treatment ,Urology ,Case Report ,Antineoplastic Agents ,Mediastinal yolk sac tumor ,Mediastinal Neoplasms ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,Renal Dialysis ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,Renal insufficiency ,Etoposide ,Medicine(all) ,Chemotherapy ,business.industry ,Endodermal Sinus Tumor ,Mediastinum ,Area under the curve ,General Medicine ,Surgery ,Regimen ,030104 developmental biology ,Hemodialysis ,030220 oncology & carcinogenesis ,Pharmacodynamics ,Concomitant ,Cisplatin ,Tomography, X-Ray Computed ,business ,medicine.drug - Abstract
Background: The safety and efficacy of chemotherapy for patients undergoing concomitant hemodialysis have not been fully established and optimal doses of anti-cancer drugs and best timing of hemodialysis remains unclear. Although chemosensitive cancers, such as germ cell tumors, treated with chemotherapy should have sufficient dose intensity maintained to achieve the desired effect, many patients with cancer undergoing hemodialysis might be under-treated because the pharmacokinetics of anti-cancer drugs in such patients remains unknown. Case presentation: We describe a 31-year-old Japanese man with a mediastinal yolk sac tumor treated with surgery followed by five cycles of chemotherapy containing cisplatin and etoposide while concomitantly undergoing hemodialysis. The doses of these agents used in the first cycle were 50% of the standard dose of cisplatin (10 mg/m2) and 60% of the standard dose of etoposide (60 mg/m2) on days 1 through to 5; the doses were subsequently escalated to 75% with both agents. Hemodialysis was started 1 hour after infusions of these agents. Severe hematological toxicities were observed despite successful treatment. During treatment with concurrent hemodialysis, pharmacokinetic analysis of cisplatin was performed and its relationship with adverse effects was assessed. Compared with patients with normal renal function, the maximum drug concentration was higher, and concentration increased in the interval between hemodialysis and the subsequent cisplatin infusion, resulting in a higher area under the curve despite a reduction in the dose to 75% of the standard regimen. Conclusions: Because of the altered pharmacokinetics pharmacodynamics status of patients with renal dysfunction undergoing hemodialysis, pharmacokinetics pharmacodynamics analysis is deemed to be helpful for effective and safe management of chemotherapy in patients undergoing hemodialysis.
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- 2017
64. Efficacy of protocol-based pharmacotherapy management on anticoagulation with warfarin for patients with cardiovascular surgery
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Yoshiki Katada, Kazuhisa Sakamoto, Taro Nakatsu, Yuki Sato, Hiromi Taue, Mizuho Odaka, Kazuhiro Yamazaki, Kazuo Matsubara, Hisashi Sakaguchi, Kenji Minakata, Kyokun Uehara, Ryuzo Sakata, Kenji Minatoya, Shunsaku Nakagawa, Ikuko Yano, Atsushi Yonezawa, and Y. Kayano
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Male ,medicine.medical_specialty ,Time Factors ,Medication Therapy Management ,medicine.medical_treatment ,Hemorrhage ,030204 cardiovascular system & hematology ,Pharmacists ,Cohort Studies ,03 medical and health sciences ,0302 clinical medicine ,Pharmacotherapy ,Aortic valve replacement ,Mitral valve ,Thromboembolism ,medicine ,Humans ,Pharmacology (medical) ,cardiovascular diseases ,030212 general & internal medicine ,International Normalized Ratio ,Cardiac Surgical Procedures ,Aged ,Retrospective Studies ,Pharmacology ,Aged, 80 and over ,Dose-Response Relationship, Drug ,business.industry ,Mitral valve replacement ,Warfarin ,Anticoagulants ,Atrial fibrillation ,Middle Aged ,medicine.disease ,Surgery ,medicine.anatomical_structure ,Cohort ,Prothrombin Time ,Female ,Drug Monitoring ,business ,Pharmacy Service, Hospital ,Algorithms ,medicine.drug ,Blood sampling - Abstract
SummaryWhat is known and objective Anticoagulation therapy with warfarin requires periodic monitoring of prothrombin time-international normalized ratio (PT-INR) and adequate dose adjustments based on the data to minimize the risk of bleeding and thromboembolic events. In our hospital, we have developed protocol-based pharmaceutical care, which we called protocol-based pharmacotherapy management (PBPM), for warfarin therapy. The protocol requires pharmacists to manage timing of blood sampling for measuring PT-INR and warfarin dosage determination based on an algorithm. This study evaluated the efficacy of PBPM in warfarin therapy by comparing to conventional pharmaceutical care. METHODS From October 2013 to June 2015, a total of 134 hospitalized patients who underwent cardiovascular surgeries received post-operative warfarin therapy. The early series of patients received warfarin therapy as the conventional care (control group, n=77), whereas the latter received warfarin therapy based on the PBPM (PBPM group, n=68). These patients formed the cohort of the present study and were retrospectively analysed. RESULTS The indications for warfarin included aortic valve replacement (n=56), mitral valve replacement (n=4), mitral valve plasty (n=22) and atrial fibrillation (n=29). There were no differences in patients' characteristics between both groups. The percentage time in therapeutic range in the first 10 days was significantly higher in the PBPM group (47.1%) than that in the control group (34.4%, P
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- 2017
65. Accumulation of alpha-fluoro-beta-alanine and fluoro mono acetate in a patient with 5-fluorouracil-associated hyperammonemia
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Kazuo Matsubara, Yoshitaka Nishikawa, Taro Funakoshi, Manabu Muto, Shin'ichi Miyamoto, Takeshi Matsubara, Atsushi Yonezawa, Motoko Yanagita, Takahiro Horimatsu, and Shunsaku Nakagawa
- Subjects
0301 basic medicine ,Male ,Cancer Research ,medicine.medical_specialty ,Antimetabolites, Antineoplastic ,medicine.medical_treatment ,Fluoroacetates ,Pharmacology toxicology ,Toxicology ,Gastroenterology ,End stage renal disease ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,Ammonia ,Renal Dialysis ,Internal medicine ,Antineoplastic Combined Chemotherapy Protocols ,medicine ,Humans ,Hyperammonemia ,Pharmacology (medical) ,Recurrent Colorectal Cancer ,Diabetic Nephropathies ,Alpha-fluoro-beta-alanine ,Aged ,Pharmacology ,Chemotherapy ,business.industry ,medicine.disease ,Combined Modality Therapy ,030104 developmental biology ,Endocrinology ,Oncology ,Fluorouracil ,030220 oncology & carcinogenesis ,beta-Alanine ,business ,Colorectal Neoplasms ,medicine.drug - Abstract
High-dose 5-fluorouracil (5-FU) containing chemotherapy occasionally causes hyperammonemia and can be lethal. However, the mechanism of 5FU-associated hyperammonemia has not been known. The aim of this study was to reveal the pharmacokinetics of 5-FU-associated hyperammonemia in a recurrent colorectal cancer patient with end-stage renal disease (ESRD).We experienced a case of hyperammonemia during mFOLFOX6 plus bevacizumab therapy for recurrent colorectal cancer. He was a dialyzed patient due to diabetic nephropathy and was registered to prospective blood sampling for pharmacokinetics analysis during chemotherapy. Blood concentrations of 5-FU and its catabolites were determined by inductively coupled plasma-mass spectrometry.The patient developed hyperammonemia encephalopathy 41 h after the initiation of continuous 5-FU infusion (on the third day). Before onset of hyperammonemia encephalopathy, serum alpha-fluoro-beta-alanine (FBAL, 59.2 µg/ml) and fluoro mono acetate (FMA, 905.8 ng/ml) were gradually increased. After hemodialysis for hyperammonemia, FBAL and FMA were collaterally decreased and his symptom was improved. Other intermediate catabolites of 5-FU, dihydrofluorouracil, and alpha-fluoro-beta-ureidopropionic acid were not changed.We found increases of serum FBAL and FMA under the condition of hyperammonemia in the patient with ESRD during mFOLFOX6 plus bevacizumab therapy. This research supported the hypothesis that impairment of tricarboxylic acid (TCA) cycle by FMA would cause 5-FU-associated hyperammonemia.
- Published
- 2017
66. Functional involvement of RFVT3/SLC52A3 in intestinal riboflavin absorption
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Kazuo Matsubara, Yoshiaki Yao, Tomohiro Omura, Atsushi Yonezawa, Hiroki Yoshimatsu, Kumiko Sugano, and Shunsaku Nakagawa
- Subjects
Physiology ,Riboflavin ,Biological Transport, Active ,Absorption (skin) ,Biology ,Real-Time Polymerase Chain Reaction ,Transfection ,Mice ,Ileum ,Physiology (medical) ,medicine ,Animals ,Humans ,RNA, Messenger ,Intestinal Mucosa ,Cells, Cultured ,In Situ Hybridization ,Hepatology ,digestive, oral, and skin physiology ,Gastroenterology ,Membrane Transport Proteins ,Transporter ,Biological membrane ,Small intestine ,Methylene Blue ,HEK293 Cells ,Jejunum ,medicine.anatomical_structure ,Intestinal Absorption ,Biochemistry ,Vitamin b2 - Abstract
Riboflavin, also known as vitamin B2, is transported across the biological membrane into various organs by transport systems. Riboflavin transporter RFVT3 is expressed in the small intestine and has been suggested to localize in the apical membranes of the intestinal epithelial cells. In this study, we investigated the functional involvement of RFVT3 in riboflavin absorption using intestinal epithelial T84 cells and mouse small intestine. T84 cells expressed RFVT3 and conserved unidirectional riboflavin transport corresponding to intestinal absorption. Apical [3H]riboflavin uptake was pH-dependent in T84 cells. This uptake was not affected by Na+ depletion at apical pH 6.0, although it was significantly decreased at apical pH 7.4. The [3H]riboflavin uptake from the apical side of T84 cells was prominently inhibited by the RFVT3 selective inhibitor methylene blue and significantly decreased by transfection of RFVT3-small-interfering RNA. In the gastrointestinal tract, RFVT3 was expressed in the jejunum and ileum. Mouse jejunal and ileal permeabilities of [3H]riboflavin were measured by the in situ closed-loop method and were significantly reduced by methylene blue. These results strongly suggest that RFVT3 would functionally be involved in riboflavin absorption in the apical membranes of intestinal epithelial cells.
- Published
- 2014
67. Urinary chemokine (C-C motif) ligand 2 (monocyte chemotactic protein-1) as a tubular injury marker for early detection of cisplatin-induced nephrotoxicity
- Author
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Aiko Ozawa, Kumiko Nishihara, Takaharu Ichimura, Shunsaku Nakagawa, Kazuo Matsubara, Joseph V. Bonventre, Haruka Shinke, Ken-ichi Inui, Satohiro Masuda, and Atsushi Yonezawa
- Subjects
Male ,Chemokine ,medicine.medical_specialty ,Urinary system ,Protein Array Analysis ,Antineoplastic Agents ,Biology ,Biochemistry ,Article ,Nephrotoxicity ,Kidney Tubules, Proximal ,Monocyte chemotactic protein-1 ,Internal medicine ,medicine ,CXCL10 ,Animals ,RNA, Messenger ,Rats, Wistar ,KIM-1 ,Chemokine CCL2 ,Pharmacology ,Cisplatin ,Kidney ,Acute kidney injury ,Microarray analysis ,Renal proximal tubule cells ,medicine.disease ,Kidney injury molecule-1 ,Rats ,CCL20 ,Endocrinology ,medicine.anatomical_structure ,Gene Expression Regulation ,biology.protein ,Kidney Diseases ,Transcriptome ,Cell Adhesion Molecules ,Biomarkers ,medicine.drug ,Signal Transduction ,MCP-1 - Abstract
Because of the difficulty in detecting segment-specific response in the kidney, we investigated the molecular events underlying acute kidney injury in the proximal tubules of rats with cisplatin (cis-diamminedichloroplatinum II)-induced nephrotoxicity. Microarray analysis revealed that mRNA levels of several cytokines and chemokines, such as interleukin-1beta, chemokine (C-C motif) ligand (CCL) 2, CCL20, chemokine (C-X-C motif) ligand (CXCL) 1, and CXCL10 were significantly increased after cisplatin treatment in both isolated proximal tubules and whole kidney. Interestingly, tubular CCL2 mRNA levels increased soon after cisplatin administration, whereas CCL2 mRNA levels in whole kidney first decreased and then increased. Levels of both CCL2 and kidney injury molecule-1 (KIM-1) in the whole kidney increased after cisplatin administration. Immunofluorescence analysis revealed CCL2 changes in the proximal tubular cells initially and then in the medullary interstitium. Urinary CCL2 excretion significantly increased approximately 3-fold compared with controls the day after cisplatin administration (5 mg/kg), when no changes were observed plasma creatinine and blood urea nitrogen levels. Urinary levels of KIM-1 also increased 3-fold after cisplatin administration. In addition, urinary CCL2 rather than KIM-1 increased in chronic renal failure rats after administration of low-dose cisplatin (2 mg/kg), suggesting that urinary CCL2 was selective for cisplatin-induced nephrotoxicity in renal impairment. These results indicated that the increase in cytokine and chemokine expression in renal epithelial cells might be responsible for kidney deterioration in cisplatin-induced nephrotoxicity, and that urinary CCL2 is associated with tubular injury and serves as a sensitive and noninvasive marker for the early detection of cisplatin-induced tubular injury.
- Published
- 2013
68. Involvement of autophagy in the pharmacological effects of the mTOR inhibitor everolimus in acute kidney injury
- Author
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Satohiro Masuda, Ken-ichi Inui, Shunsaku Nakagawa, and Kumiko Nishihara
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Biology ,Pharmacology ,Kidney ,Cell Line ,Dogs ,medicine ,Autophagy ,Animals ,Humans ,Proximal tubule ,Everolimus ,Rats, Wistar ,Muscle, Skeletal ,PI3K/AKT/mTOR pathway ,Cisplatin ,Sirolimus ,Mammalian target of rapamycin ,TOR Serine-Threonine Kinases ,Acute kidney injury ,Kidney metabolism ,Biomarker ,medicine.disease ,Rats ,medicine.anatomical_structure ,biological phenomena, cell phenomena, and immunity ,Microtubule-Associated Proteins ,Biomarkers ,Immunosuppressive Agents ,medicine.drug ,Kidney disease - Abstract
Inhibitors of mammalian target of rapamycin (mTOR) have immunosuppressive and anti-cancer effects, but their effects on the progression of kidney disease are not fully understood. Using cells from normal kidney epithelial cell lines, we found that the antiproliferative effects of mTOR inhibitor everolimus accompanied the accumulation of a marker for cellular autophagic activity, the phosphatidylethanolamine-conjugated form of microtubule-associated protein 1 light chain 3 (LC3-II) in cells. We also showed that the primary autophagy factor UNC-51-like kinase 1 was involved in the antiproliferative effects of everolimus. Levels of LC3-II decreased in the kidneys of rats treated with ischemia-reperfusion or cisplatin; however, renal LC3-II levels increased after administration of everolimus to rats subjected to ischemia-reperfusion or cisplatin treatment. Simultaneously, increased signals for kidney injury molecule-1 and single-stranded DNA and decreased signals for Ki-67 in the proximal tubules were observed after treatment with everolimus, indicating that everolimus diminished renal function after acute tubular injury. We also found leakage of LC3 protein into rat urine after treatment with everolimus, and urinary LC3 protein was successfully measured between 0.1 and 500 ng/mL by using an enzyme-linked immunosorbent assay. Urinary LC3 levels were increased after administration of everolimus to rats subjected to ischemia-reperfusion or cisplatin treatment, suggesting that renal LC3-II and urinary LC3 protein are new biomarkers for autophagy in acute kidney injury. Taken together, our results demonstrated that the induction of autophagy by everolimus aggravates tubular dysfunction during recovery from kidney injury.
- Published
- 2012
69. Disruption of Slc52a3 gene causes neonatal lethality with riboflavin deficiency in mice
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Tomohiro Omura, Kumiko Sugano, Atsushi Yonezawa, Kazuo Matsubara, Ikuko Yano, Kaori Yamanishi, Hiroki Yoshimatsu, Yoshiaki Yao, Takayuki Nakagawa, Shunsaku Nakagawa, Satoshi Imai, Satohiro Masuda, and Ken-ichi Inui
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Placenta ,Riboflavin ,Hyperlipidemias ,Hypoglycemia ,Biology ,Article ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Riboflavin Deficiency ,In vivo ,Pregnancy ,Internal medicine ,Hyperlipidemia ,medicine ,Animals ,Humans ,heterocyclic compounds ,Mice, Knockout ,Fetus ,Multidisciplinary ,digestive, oral, and skin physiology ,Membrane Transport Proteins ,food and beverages ,Transporter ,medicine.disease ,030104 developmental biology ,Endocrinology ,Biochemistry ,Animals, Newborn ,Riboflavin transport ,Female ,human activities ,030217 neurology & neurosurgery ,Homeostasis - Abstract
Homeostasis of riboflavin should be maintained by transporters. Previous in vitro studies have elucidated basic information about riboflavin transporter RFVT3 encoded by SLC52A3 gene. However, the contribution of RFVT3 to the maintenance of riboflavin homeostasis and the significance in vivo remain unclear. Here, we investigated the physiological role of RFVT3 using Slc52a3 knockout (Slc52a3−/−) mice. Most Slc52a3−/− mice died with hyperlipidemia and hypoglycemia within 48 hr after birth. The plasma and tissue riboflavin concentrations in Slc52a3−/− mice at postnatal day 0 were dramatically lower than those in wild-type (WT) littermates. Slc52a3−/− fetuses showed a lower capacity of placental riboflavin transport compared with WT fetuses. Riboflavin supplement during pregnancy and after birth reduced neonatal death and metabolic disorders. To our knowledge, this is the first report to indicate that Rfvt3 contributes to placental riboflavin transport, and that disruption of Slc52a3 gene caused neonatal mortality with hyperlipidemia and hypoglycemia owing to riboflavin deficiency.
- Published
- 2016
70. Impact of Cyclin B2 and Cell division cycle 2 on tubular hyperplasia in progressive chronic renal failure rats
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Satohiro Masuda, Atsushi Yonezawa, Joseph V. Bonventre, Ken-ichi Inui, Takaharu Ichimura, Shunsaku Nakagawa, and Kumiko Nishihara
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Male ,medicine.medical_specialty ,Cell division ,Physiology ,Protein Array Analysis ,Mitosis ,Cell Cycle Proteins ,Protein Serine-Threonine Kinases ,Muscle hypertrophy ,Cyclin-dependent kinase ,Internal medicine ,CDC2 Protein Kinase ,medicine ,Animals ,Cyclin B2 ,Everolimus ,Rats, Wistar ,Cyclin ,Sirolimus ,Kidney ,Cyclin-dependent kinase 1 ,Hyperplasia ,biology ,TOR Serine-Threonine Kinases ,Cell Cycle ,Intracellular Signaling Peptides and Proteins ,Reproducibility of Results ,Articles ,Cell cycle ,medicine.disease ,Cyclin-Dependent Kinases ,Rats ,Up-Regulation ,Kidney Tubules ,Endocrinology ,medicine.anatomical_structure ,biology.protein ,Kidney Failure, Chronic ,Immunosuppressive Agents - Abstract
To clarify the specific molecular events of progressive tubular damage in chronic renal failure (CRF), we conducted microarray analyses using isolated proximal tubules from subtotally nephrectomized (Nx) rats as a model of CRF. Our results clearly demonstrated time-dependent changes in gene expression profiles localized to proximal tubules. The expression of mitosis-specific genes Cyclin B2 and Cell division cycle 2 (Cdc2) was significantly and selectively increased in the proximal tubules during the compensated period but decreased to basal level in the end-stage period. Administration of everolimus, a potent inhibitor of mammalian target of rapamycin, markedly reduced compensatory hypertrophy and hyperplasia of epithelial cells, which was accompanied by complete abolishment of the expression of Cyclin B2 and Cdc2 enhancement; renal function was then severely decreased. Treatment with the Cdc2 inhibitor 2-cyanoethyl alsterpaullone clearly decreased epithelial cell hyperplasia, based on staining of phosphorylated histone H3 and Ki-67, while hypertrophy was not inhibited. In conclusion, we have demonstrated roles of Cyclin B2 and Cdc2 in the epithelial hyperplasia in response to Nx. These results advance the knowledge of the contribution of cell cycle regulators, especially M phase, in pathophysiology of tubular restoration and/or degeneration, and these two molecules are suggested to be a marker for the proliferation of proximal tubular cells in CRF.
- Published
- 2010
71. Role of ubiquitin ligase HRD1 in a cellular model of Parkinson's disease
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Masato Naito, Kazuo Matsubara, Luna Nomura, Atsushi Yonezawa, Satoshi Imai, Tomohiro Omura, Hiroki Matsuda, Takayuki Nakagawa, and Shunsaku Nakagawa
- Subjects
Parkinson's disease ,Applied Mathematics ,General Mathematics ,biology.protein ,medicine ,Cellular model ,Biology ,medicine.disease ,Ubiquitin ligase ,Cell biology - Published
- 2018
72. Pharmacokinetics and safety of FOLFOX therapy in patients undergoing hemodialysis
- Author
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Shunsaku Nakagawa, Takahiro Horimatsu, Motoko Yanagita, Yohei Harada, Taro Funakoshi, Manabu Muto, Masami Nakajima, Shigeki Kataoka, Toshihiko Kirishima, and Shina Sueki
- Subjects
medicine.medical_specialty ,Oncology ,FOLFOX ,business.industry ,medicine.medical_treatment ,medicine ,In patient ,Hematology ,Hemodialysis ,business ,medicine.drug ,Surgery - Published
- 2017
73. Pharmacokinetics and pharmacodynamics of mycophenolic acid in Nagase analbuminemic rats: Evaluation of protein binding effects using the modeling and simulation approach
- Author
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Atsushi Yonezawa, Kazuo Matsubara, Shunsaku Nakagawa, Ikuko Yano, Misaki Kawanishi, and Kazuaki Yoshimura
- Subjects
Pharmaceutical Science ,Pharmacology ,Models, Biological ,Mycophenolic acid ,Glucuronides ,IMP Dehydrogenase ,Pharmacokinetics ,IMP dehydrogenase ,Acetylglucosaminidase ,medicine ,Animals ,Pharmacology (medical) ,Computer Simulation ,Genetic Predisposition to Disease ,Volume of distribution ,Chemistry ,Mycophenolic Acid ,NONMEM ,stomatognathic diseases ,Disease Models, Animal ,Phenotype ,Liver ,Nonlinear Dynamics ,Free fraction ,Pharmacodynamics ,Drug Monitoring ,Rats, Transgenic ,Glucuronide ,Hypoalbuminemia ,Immunosuppressive Agents ,medicine.drug ,Protein Binding - Abstract
This study aimed to examine the pharmacokinetics and pharmacodynamics of mycophenolic acid (MPA) in Nagase analbuminemic rats (NARs) to evaluate the effect of protein binding on the associated inosine-5'-monophosphate dehydrogenase (IMPDH) activity. Free fractions of MPA in the control rats and NARs were 2.09 and 24.8%, respectively. Pharmacokinetic and pharmacodynamic parameters simultaneously obtained by the nonlinear mixed effects modeling program NONMEM explained reasonably well the concentrations of MPA and MPA glucuronide as well as IMPDH activity in both rats. NARs showed a higher clearance and a smaller volume of distribution based on the free MPA concentration than the controls did, besides the increase in free fraction. The half-maximal inhibitory concentration based on free MPA was estimated as 163 ng/mL for both rats. Simulations based on the obtained pharmacokinetic and pharmacodynamic parameters showed that the area under the IMPDH activity-time curve decreased non-linearly according to the increase in free fraction of MPA. In conclusion, the experimental data obtained from NARs followed by the modeling and simulation approach quantitatively clarified that the free MPA concentration was suitable for the biomarker of immunosuppressive effect of MPA. Dose adjustments based on the total MPA may cause unnecessary overexposure to MPA in patients with hypoalbuminemia.
- Published
- 2015
74. [The Contribution of GMP-grade Hospital Preparation to Translational Research]
- Author
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Tomohiro Omura, Shunsaku Nakagawa, Kazuo Matsubara, Atsushi Yonezawa, Ikuko Minami, and Moto Kajiwara
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Quality Control ,medicine.medical_specialty ,media_common.quotation_subject ,International Cooperation ,MEDLINE ,Pharmaceutical Science ,Pharmacy ,Translational research ,Translational Research, Biomedical ,Patient safety ,Japan ,Medicine ,Quality (business) ,Medical physics ,media_common ,Pharmacology ,Clinical Trials as Topic ,business.industry ,Sterilization ,Drugs, Investigational ,University hospital ,Clinical trial ,Clinical research ,Pharmaceutical Preparations ,Family medicine ,Patient Safety ,business ,Pharmacy Service, Hospital - Abstract
Translational research is important for applying the outcomes of basic research studies to practical medical treatments. In exploratory early-phase clinical trials for an innovative therapy, researchers should generally manufacture investigational agents by themselves. To provide investigational agents with safety and high quality in clinical studies, appropriate production management and quality control are essential. In the Department of Pharmacy of Kyoto University Hospital, a manufacturing facility for sterile drugs was established, independent of existing manufacturing facilities. Manuals on production management and quality control were developed according to Good Manufacturing Practices (GMP) for Investigational New Drugs (INDs). Advanced clinical research has been carried out using investigational agents manufactured in our facility. These achievements contribute to both the safety of patients and the reliability of clinical studies. In addition, we are able to do licensing-out of our technique for the manufacture of investigational drugs. In this symposium, we will introduce our GMP grade manufacturing facility for sterile drugs and discuss the role of GMP grade hospital preparation in translational research.
- Published
- 2015
75. Novel 5-fluorouracil-resistant human esophageal squamous cell carcinoma cells with dihydropyrimidine dehydrogenase overexpression
- Author
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Osamu, Kikuchi, Shinya, Ohashi, Yukie, Nakai, Shunsaku, Nakagawa, Kazuaki, Matsuoka, Takashi, Kobunai, Teiji, Takechi, Yusuke, Amanuma, Masahiro, Yoshioka, Tomomi, Ida, Yoshihiro, Yamamoto, Yasushi, Okuno, Shin'ichi, Miyamoto, Hiroshi, Nakagawa, Kazuo, Matsubara, Tsutomu, Chiba, and Manabu, Muto
- Subjects
Original Article - Abstract
5-Fluorouracil (5-FU) is a key drug for the treatment of esophageal squamous cell carcinoma (ESCC); however, resistance to it remains a critical limitation to its clinical use. To clarify the mechanisms of 5-FU resistance of ESCC, we originally established 5-FU-resistant ESCC cells, TE-5R, by step-wise treatment with continuously increasing concentrations of 5-FU. The half maximal inhibitory concentration of 5-FU showed that TE-5R cells were 15.6-fold more resistant to 5-FU in comparison with parental TE-5 cells. TE-5R cells showed regional copy number amplification of chromosome 1p including the DPYD gene, as well as high mRNA and protein expressions of dihydropyrimidine dehydrogenase (DPD), an enzyme involved in 5-FU degradation. 5-FU treatment resulted in a significant decrease of the intracellular 5-FU concentration and increase of the concentration of α-fluoro-ureidopropionic acid (FUPA), a metabolite of 5-FU, in TE-5R compared with TE-5 cells in vitro. Conversely, gimeracil, a DPD inhibitor, markedly increased the intracellular 5-FU concentration, decreased the intracellular FUPA concentration, and attenuated 5-FU resistance of TE-5R cells. These results indicate that 5-FU resistance of TE-5R cells is due to the rapid degradation of 5-FU by DPD overexpression. The investigation of 5-FU-resistant ESCC with DPYD gene copy number amplification and consequent DPD overexpression may generate novel biological evidence to explore strategies against ESCC with 5-FU resistance.
- Published
- 2015
76. Extracellular nucleotides from dying cells act as molecular signals to promote wound repair in renal tubular injury
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Tomohiro Omura, Kazuo Matsubara, Shunsaku Nakagawa, Ikuko Yano, Takayuki Nakagawa, and Atsushi Yonezawa
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Poor prognosis ,Time Factors ,Physiology ,Cell Communication ,Biology ,Severity of Illness Index ,Cell Line ,Adenosine Triphosphate ,Cell to cell communication ,Cell Movement ,medicine ,Extracellular ,Purinergic P2 Receptor Antagonists ,Animals ,Nucleotide ,Rats, Wistar ,Cell Proliferation ,chemistry.chemical_classification ,Wound Healing ,Cell Death ,urogenital system ,Receptors, Purinergic P2 ,Acute kidney injury ,Acute Kidney Injury ,medicine.disease ,Pathophysiology ,Disease Models, Animal ,Ki-67 Antigen ,Kidney Tubules ,chemistry ,Cisplatin ,Biomarkers ,Signal Transduction - Abstract
Acute kidney injury (AKI) often correlates with poor prognosis and is followed by various severe unfavorable systemic outcomes. It is important to understand the pathophysiology of AKI for the development of novel therapeutic approaches toward promoting renal regeneration after injury. Recent studies have indicated that AKI-induced tubular cell death plays an active role in the onset of tissue regeneration; however, the mechanisms underlying renal tubular repair after injury have yet to be understood. In the present study, we explored molecules that might serve as “danger” signals in mediating tubular regeneration. Kidneys of rats systemically administered the nephrotoxicant cisplatin (to induce AKI) exhibited massive cell proliferation. The proportion of proliferating cells in the total cell distribution was highest in the outer stripe of the outer medulla coincided with where the tubular damage was the most severe in this study. This finding suggests that soluble factors may have been released from damaged cells to stimulate the proliferation of neighboring tubular epithelial cells. In elucidating the mechanism of dying cell-to-surviving cell communication using normal rat kidney NRK-52E epithelial cells, we found a significant increase in ATP levels in supernatants of these cells after the induction of cell death using ultraviolet irradiation. Furthermore, treatment of conditioned supernatants with apyrase or suramin, which inhibits purinergic signaling, resulted in significant decreases in cell proliferation and migration activities. These results demonstrate a novel role for extracellular nucleotides, probably as danger signals in aggravating tubular regeneration after AKI.
- Published
- 2014
77. Pharmacokinetics and Pharmacodynamics of Once-Daily Tacrolimus Compared With Twice-Daily Tacrolimus in the Early Stage After Living Donor Liver Transplantation.
- Author
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Mami Iwasaki, Ikuko Yano, Sachio Fukatsu, Sachiyo Hashi, Yuki Yamamoto, Mitsuhiro Sugimoto, Masahide Fukudo, Satohiro Masuda, Shunsaku Nakagawa, Atsushi Yonezawa, Toshimi Kaido, Shinji Uemoto, and Kazuo Matsubara
- Published
- 2018
- Full Text
- View/download PDF
78. Time-Dependent Structural Alteration of Rituximab Analyzed by LC/TOF-MS after a Systemic Administration to Rats
- Author
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Masahiro Tsuda, Ikuko Yano, Yuki Otani, Kazuo Matsubara, Atushi Yonezawa, Takayuki Nakagawa, Yasuaki Ikemi, Tomohiro Omura, Shunsaku Nakagawa, and Satoshi Imai
- Subjects
0301 basic medicine ,Time Factors ,Physiology ,lcsh:Medicine ,Endogeny ,Pharmacology ,Biochemistry ,Mass Spectrometry ,Analytical Chemistry ,Spectrum Analysis Techniques ,Cysteine Proteases ,Medicine and Health Sciences ,Enzyme-Linked Immunoassays ,Post-Translational Modification ,lcsh:Science ,chemistry.chemical_classification ,Multidisciplinary ,Organic Compounds ,Mass Spectra ,Hematology ,Proteases ,Body Fluids ,Enzymes ,Amino acid ,Chemistry ,Blood ,Physical Sciences ,Systemic administration ,Rituximab ,Anatomy ,Research Article ,medicine.drug ,medicine.medical_specialty ,medicine.drug_class ,Carbohydrates ,Research and Analysis Methods ,Monoclonal antibody ,Blood Plasma ,03 medical and health sciences ,Pharmacokinetics ,Affinity chromatography ,Internal medicine ,medicine ,Animals ,Rats, Wistar ,Immunoassays ,Organic Chemistry ,lcsh:R ,Antibody-Dependent Cell Cytotoxicity ,Chemical Compounds ,Biology and Life Sciences ,Proteins ,Inductively Coupled Plasma Emission Spectroscopy ,Complement System Proteins ,030104 developmental biology ,Endocrinology ,Enzyme ,chemistry ,Enzymology ,Immunologic Techniques ,lcsh:Q ,Chromatography, Liquid - Abstract
Therapeutic monoclonal antibodies (mAbs) have heterogeneities in their structures. Multiple studies have reported that the variety of post-translational modifications could affect the pharmacokinetic profiles or pharmacological potencies of therapeutic mAbs. Taking into the account that the structural modification of mAbs would affect the efficacy, it is worth investigating the structural alteration of therapeutic mAbs in the blood and the relationship between their structures and pharmacological effects. Herein, we have developed the method to isolate rituximab from plasma in which endogenous IgGs interfere the detection of rituximab, and successfully developed the analytical method with a liquid chromatograph time-of-flight mass spectrometer to detect the structure of rituximab in plasma with errors less than 30 parts per millions. Eight types of carbohydrate chains in rituximab were detected by this method. Interestingly, time-dependent changes in carbohydrate chains such as AAF (G2F) and GnGn (G0) were observed in rats, although the amino acids were stable. Additionally, these structural changes were observed via incubation in plasma as in the rat experiment, suggesting that a certain type of enzyme in plasma caused the alterations of the carbohydrate chains. The present analytical methods could clarify the actual pharmacokinetics of therapeutic mAbs, and help to evaluate the interindividual variations in pharmacokinetics and efficacy.
- Published
- 2017
79. mTOR inhibitor everolimus ameliorates progressive tubular dysfunction in chronic renal failure rats
- Author
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Satohiro Masuda, Shunsaku Nakagawa, Kumiko Nishihara, and Ken-ichi Inui
- Subjects
Male ,medicine.medical_specialty ,Urinary system ,Biochemistry ,Lesion ,Internal medicine ,medicine ,Animals ,Everolimus ,Rats, Wistar ,Protein Kinase Inhibitors ,PI3K/AKT/mTOR pathway ,Pharmacology ,Sirolimus ,Kidney ,Protein synthesis inhibitor ,business.industry ,TOR Serine-Threonine Kinases ,medicine.disease ,Rats ,Endocrinology ,medicine.anatomical_structure ,Kidney Tubules ,Renal physiology ,Disease Progression ,Kidney Failure, Chronic ,medicine.symptom ,business ,Protein Kinases ,medicine.drug ,Kidney disease - Abstract
Responsible factors in progressive tubular dysfunction in chronic renal failure have not been fully identified. In the present study, we hypothesized that the mammalian target of rapamycin, mTOR, was a key molecule in the degenerative and progressive tubular damage in chronic renal failure. Everolimus, an mTOR inhibitor, was administered for 14 days in 5/6 nephrectomized (Nx) rats at 2 and 8 weeks after renal ablation. Marked activation of the mTOR pathway was found at glomeruli and proximal tubules in remnant kidneys of Nx rats. The reduced expression levels of the phosphorylated S6 indicated the satisfactory pharmacological effects of treatment with everolimus for 14 days. Everolimus suppressed the accumulation of smooth muscle alpha actin, infiltration of macrophages and expression of kidney injury molecule-1 in the proximal tubules. In addition, everolimus-treatment restored the tubular reabsorption of albumin, and had a restorative effect on the expression levels of membrane transporters in the polarized proximal tubular epithelium, when its administration was started at 8 weeks after Nx. These results indicate that the constitutively activated mTOR pathway in proximal tubules has an important role in the progressive tubular dysfunction, and that mTOR inhibitors have renoprotective effects to improve the proximal tubular functions in end-stage renal disease.
- Published
- 2009
80. Gefitinib and Erlotinib Lead to Phosphorylation of Eukaryotic Initiation Factor 2 Alpha Independent of Epidermal Growth Factor Receptor in A549 Cells
- Author
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Shunsaku Nakagawa, Satoshi Imai, Kazuo Matsubara, Satoshi Koyama, Tomohiro Omura, Ikuko Yano, Takayuki Nakagawa, and Atsushi Yonezawa
- Subjects
Eukaryotic Initiation Factor-2 ,lcsh:Medicine ,Antineoplastic Agents ,Biology ,Cell Line ,Taurochenodeoxycholic Acid ,Erlotinib Hydrochloride ,Gefitinib ,medicine ,Humans ,Cyclin D1 ,Epidermal growth factor receptor ,Phosphorylation ,lcsh:Science ,Cell Proliferation ,EGFR inhibitors ,A549 cell ,Multidisciplinary ,lcsh:R ,Endoplasmic Reticulum Stress ,respiratory tract diseases ,ErbB Receptors ,Pulmonary Alveoli ,Quinazolines ,Cancer research ,biology.protein ,lcsh:Q ,Erlotinib ,Signal transduction ,Lung Diseases, Interstitial ,Tyrosine kinase ,Research Article ,Signal Transduction ,medicine.drug - Abstract
Gefitinib and erlotinib are anticancer agents, which inhibit epidermal growth factor receptor (EGFR) tyrosine kinase. Interstitial lung disease (ILD) occurs in patients with non-small cell lung cancer receiving EGFR inhibitors. In the present study, we examined whether gefitinib- and erlotinib-induced lung injury related to ILD through endoplasmic reticulum (ER) stress, which is a causative intracellular mechanism in cytotoxicity caused by various chemicals in adenocarcinomic human alveolar basal epithelial cells. These two EGFR inhibitors increased Parkinson juvenile disease protein 2 and C/EBP homologous protein mRNA expressions, and activated the eukaryotic initiation factor (eIF) 2α/activating transcription factor 4 pathway without protein kinase R-like ER kinase activation in A549 cells. Gefitinib and erlotinib caused neither ER stress nor cell death; however, these agents inhibited cell growth via the reduction of cyclin-D1 expression. Tauroursodeoxycholic acid, which is known to suppress eIF2α phosphorylation, cancelled the effects of EGFR inhibitors on cyclin-D1 expression and cell proliferation in a concentration-dependent manner. The results of an EGFR-silencing study using siRNA showed that gefitinib and erlotinib affected eIF2α phosphorylation and cyclin-D1 expression independent of EGFR inhibition. Therefore, the inhibition of cell growth by these EGFR inhibitors might equate to impairment of the alveolar epithelial cell repair system via eIF2α phosphorylation and reduced cyclin-D1 expression.
- Published
- 2015
81. Pericyte MyD88 and IRAK4 control inflammatory and fibrotic responses to tissue injury.
- Author
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Leaf, Irina A., Shunsaku Nakagawa, Johnson, Bryce G., Jin Joo Cha, Mittelsteadt, Kristen, Cuckian, Kevin M., Gomez, Ivan C., Altemeier, William A., Duffield, Jeremy S., Nakagawa, Shunsaku, Cha, Jin Joo, Guckian, Kevin M, and Gomez, Ivan G
- Subjects
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INTERLEUKIN-1 receptors , *FIBROSIS , *PERICYTES , *INFLAMMATION , *CELLULAR signal transduction , *THERAPEUTICS - Abstract
Fibrotic disease is associated with matrix deposition that results in the loss of organ function. Pericytes, the precursors of myofibroblasts, are a source of pathological matrix collagens and may be promising targets for treating fibrogenesis. Here, we have shown that pericytes activate a TLR2/4- and MyD88-dependent proinflammatory program in response to tissue injury. Similarly to classic immune cells, pericytes activate the NLRP3 inflammasome, leading to IL-1β and IL-18 secretion. Released IL-1β signals through pericyte MyD88 to amplify this response. Unexpectedly, we found that MyD88 and its downstream effector kinase IRAK4 intrinsically control pericyte migration and conversion to myofibroblasts. Specific ablation of MyD88 in pericytes or pharmacological inhibition of MyD88 signaling by an IRAK4 inhibitor in vivo protected against kidney injury by profoundly attenuating tissue injury, activation, and differentiation of myofibroblasts. Our data show that in pericytes, MyD88 and IRAK4 are key regulators of 2 major injury responses: inflammatory and fibrogenic. Moreover, these findings suggest that disruption of this MyD88-dependent pathway in pericytes might be a potential therapeutic approach to inhibit fibrogenesis and promote regeneration. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
82. Extracellular nucleotides from dying cells act as molecular signals to promote wound repair in renal tubular injury.
- Author
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Shunsaku Nakagawa, Tomohiro Omura, Atsushi Yonezawa, Ikuko Yano, Takayuki Nakagawa, and Kazuo Matsubara
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NUCLEOTIDES , *RENAL tubular transport disorders , *ACUTE kidney failure , *PATHOLOGICAL physiology , *CELL death , *EPITHELIAL cells - Abstract
Acute kidney injury (AKI) often correlates with poor prognosis and is followed by various severe unfavorable systemic outcomes. It is important to understand the pathophysiology of AKI for the development of novel therapeutic approaches toward promoting renal regeneration after injury. Recent studies have indicated that AKI-induced tubular cell death plays an active role in the onset of tissue regeneration; however, the mechanisms underlying renal tubular repair after injury have yet to be understood. In the present study, we explored molecules that might serve as "danger" signals in mediating tubular regeneration. Kidneys of rats systemically administered the nephrotoxicant cisplatin (to induce AKI) exhibited massive cell proliferation. The proportion of proliferating cells in the total cell distribution was highest in the outer stripe of the outer medulla coincided with where the tubular damage was the most severe in this study. This finding suggests that soluble factors may have been released from damaged cells to stimulate the proliferation of neighboring tubular epithelial cells. In elucidating the mechanism of dying cell-to-surviving cell communication using normal rat kidney NRK-52E epithelial cells, we found a significant increase in ATP levels in supernatants of these cells after the induction of cell death using ultraviolet irradiation. Furthermore, treatment of conditioned supernatants with apyrase or suramin, which inhibits purinergic signaling, resulted in significant decreases in cell proliferation and migration activities. These results demonstrate a novel role for extracellular nucleotides, probably as danger signals in aggravating tubular regeneration after AKI. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
83. Functional involvement of RFVT3/SLC52A3 in intestinal riboflavin absorption.
- Author
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Hiroki Yoshimatsu, Atsushi Yonezawa, Yoshiaki Yao, Kumiko Sugano, Shunsaku Nakagawa, Tomohiro Omura, and Kazuo Matsubara
- Abstract
Riboflavin, also known as vitamin B2, is transported across the biological membrane into various organs by transport systems. Riboflavin transporter RFVT3 is expressed in the small intestine and has been suggested to localize in the apical membranes of the intestinal epithelial cells. In this study, we investigated the functional involvement of RFVT3 in riboflavin absorption using intestinal epithelial T84 cells and mouse small intestine. T84 cells expressed RFVT3 and conserved unidirectional riboflavin transport corresponding to intestinal absorption. Apical [ 3 H]riboflavin uptake was pH-dependent in T84 cells. This uptake was not affected by Na depletion at apical pH 6.0, although it was significantly decreased at apical pH 7.4. The [3 H]riboflavin uptake from the apical side of T84 cells was prominently inhibited by the RFVT3 selective inhibitor methylene blue and significantly decreased by transfection of RFVT3-small-interfering RNA. In the gastrointestinal tract, RFVT3 was expressed in the jejunum and ileum. Mouse jejunal and ileal permeabilities of [3 H]riboflavin were measured by the in situ closed-loop method and were significantly reduced by methylene blue. These results strongly suggest that RFVT3 would functionally be involved in riboflavin absorption in the apical membranes of intestinal epithelial cells. [ABSTRACT FROM AUTHOR]
- Published
- 2014
- Full Text
- View/download PDF
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