189 results on '"Kitagawa, Yoshinori"'
Search Results
152. Molecular cloning of rat phosphoprotein phosphatase 2Aβ cDNA and increased expressions of phosphatase 2Aα and 2Aβ in rat liver tumors
- Author
-
Kitagawa, Yoshinori, primary, Sakai, Ryuichi, additional, Tahira, Tomoko, additional, Tsuda, Hiroyuki, additional, Ito, Nobuyuki, additional, Sugimura, Takashi, additional, and Nagao, Minako, additional
- Published
- 1988
- Full Text
- View/download PDF
153. Activated K-rasin Tumorigenic and Non-tumorigenic Cell Variants from a Rat Colon Adenocarcinoma, Induced by Dimethylhydrazine
- Author
-
Caignard, Anne, primary, Kitagawa, Yoshinori, additional, Sato, Shigeaki, additional, and Nagao, Minako, additional
- Published
- 1988
- Full Text
- View/download PDF
154. Synthesis of Heterocyclic Compounds Using Diketene: On the Addition Reaction to the C=C Double Bond of Diketene
- Author
-
Kato, Tetsuzo, primary, Sato, Masayuki, additional, Katagiri, Nobuya, additional, and Kitagawa, Yoshinori, additional
- Published
- 1974
- Full Text
- View/download PDF
155. Studies on ketene and its derivatives. CV. Photoreaction of diketene with sec-alcohols.
- Author
-
KATO, TETSUZO, primary, SATO, MASAYUKI, additional, KITAGAWA, YOSHINORI, additional, and SATO, RENZO, additional
- Published
- 1981
- Full Text
- View/download PDF
156. Tetsu-to-Hagane
- Author
-
SHIMOKAWA, Yoshio, primary, FUJII, Takehiko, additional, and KITAGAWA, Yoshinori, additional
- Published
- 1962
- Full Text
- View/download PDF
157. Antibody production by a protease-deficient strain of methylotrophic yeast, Ogataea minuta.
- Author
-
Kuroda, Kousuke, Kitagawa, Yoshinori, Kobayashi, Kazuo, Tsumura, Haruhiko, Komeda, Toshihiro, Chiba, Yasunori, and Jigami, Yoshihumi
- Subjects
- *
ANTIBODY-enzyme conjugates - Abstract
An abstract of the paper "Antibody Production by a Protease-Deficient Strain of Methylotrophic Yeast, Ogataea minuta," by Kousuke Kuroda and colleagues is presented.
- Published
- 2006
- Full Text
- View/download PDF
158. In situ Metal Mask for Selective Area Growth of Thin Epitaxial Layers.
- Author
-
Ohkouchi, Shunsuke, Ozaki, Nobuhiko, Takata, Yoshiaki, Kitagawa, Yoshinori, Nakamura, Yusui, Ikeda, Naoki, Sugimoto, Yoshimasa, and Asakawa, Kiyoshi
- Abstract
We have developed an in situ metal mask that enables the selective formation of molecular beam epitaxially grown layers in narrow regions and the subsequent formation of marker layers. It can be fitted to a sample holder and removed in an ultrahigh-vacuum environment; therefore, device structures can be fabricated without exposing the sample surfaces to air. To explore the effectiveness of the mask, we used it to grow quantum dot (QD) layers in narrow regions and verified the perfect selectivity of the QD growth. The grown QDs exhibited high optical quality with a photoluminescence peak at approximately 1.29 µm and a linewidth of 30 meV at room temperature. Furthermore, on the selectively grown layers, we have fabricated waveguide structures that showed a high transmittance near 1.3 µm wavelength with a dip due to the absorption by the embedded QDs. The developed mask can be used for the integration of microstructures into optoelectronic functional devices. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
159. Annexin A1 accounts for an anti-inflammatory binding target of sesamin metabolites.
- Author
-
Kabe Y, Takemoto D, Kanai A, Hirai M, Ono Y, Akazawa S, Horikawa M, Kitagawa Y, Handa H, Rogi T, Shibata H, and Suematsu M
- Abstract
Sesamin [(7α,7'α,8α,8'α)-3,4:3',4'-bis(methylenedioxy)-7,9':7',9-diepoxylignane] is a major lignan in sesame seeds. Sesamin is converted to the catechol metabolite, SC1 [(7α,7'α,8α,8'α)-3',4'-methylenedioxy-7,9':7',9-diepoxylignane-3,4-diol] with anti-inflammatory effects after oral administration. However, its molecular target remains unknown. Analysis using high-performance affinity nanobeads led to the identification of annexin A1 (ANX A1) as an SC1-binding protein. SC1 was found to bind to the annexin repeat 3 region of ANX A1 with a high-affinity constant (Kd = 2.77 μmol L
-1 ). In U937 cells, SC1 exhibited an anti-inflammatory effect dependent on ANX A1. Furthermore, administration of sesamin or SC1 attenuated carbon tetrachloride-induced liver damage in mice and concurrently suppressed inflammatory responses dependent on ANX A1. The mechanism involved SC1-induced ANX A1 phosphorylation at serine 27 that facilitates extracellular ANX A1 release. Consequently, the ANX A1 released into the extracellular space suppressed the production of tumor necrosis factor α. This study demonstrates that ANX A1 acts as a pivotal target of sesamin metabolites to attenuate inflammatory responses., Competing Interests: Competing interestsD.T., Y.O., S.A., Y.K., T.R. and H.S. are employees of Suntory Wellness Ltd, which is a manufacturer of foods that contain sesamin. All authors declare no other competing interests., (© The Author(s) 2020.)- Published
- 2020
- Full Text
- View/download PDF
160. Oncogenic role of TYRO3 receptor tyrosine kinase in the progression of pancreatic cancer.
- Author
-
Morimoto M, Horikoshi Y, Nakaso K, Kurashiki T, Kitagawa Y, Hanaki T, Sakamoto T, Honjo S, Umekita Y, Fujiwara Y, and Matsura T
- Subjects
- Aged, Animals, Carcinogenesis, Cell Line, Tumor, Cell Proliferation, Disease Progression, Female, Gene Knockdown Techniques, Humans, Kaplan-Meier Estimate, MAP Kinase Signaling System, Male, Mice, Middle Aged, Neoplasm Invasiveness pathology, Neoplasm Staging, Pancreas pathology, Pancreatic Neoplasms mortality, Phosphorylation, Prognosis, Proto-Oncogene Proteins c-akt metabolism, RNA, Small Interfering metabolism, Receptor Protein-Tyrosine Kinases genetics, Xenograft Model Antitumor Assays, Pancreatic Neoplasms pathology, Receptor Protein-Tyrosine Kinases metabolism
- Abstract
The expression and functions of TYRO3, a member of the TAM receptor tyrosine kinase family, in pancreatic cancer (PC) have not been specifically elucidated. In this study, we confirmed TYRO3 expression in five human PC cell lines (PANC-1, MIA PaCa-2, BxPC-3, AsPC-1, and PK-9) using Western blotting. TYRO3 silencing and overexpression studies have revealed that TYRO3 promotes cell proliferation and invasion in PC via phosphorylation of protein kinase B (Akt) and extracellular signal-regulated kinase (ERK). Using a mouse xenograft model, we showed that tumor growth was significantly suppressed in mice subcutaneously inoculated with TYRO3-knockdown PC cells compared with mice inoculated with control PC cells. Furthermore, TYRO3 expression was examined in PC tissues obtained from 106 patients who underwent pancreatic resection for invasive ductal carcinoma through immunohistochemical staining. TYRO3-positive patients had poor prognoses for overall survival and disease-specific survival compared with TYRO3-negative patients. Multivariate analysis revealed that TYRO3 expression is an independent prognostic factor for overall survival. Our study demonstrates the critical role of TYRO3 in PC progression through Akt and ERK activation and suggests TYRO3 as a novel promising target for therapeutic strategies against PC., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
161. Multiple-endpoint genotoxicity assay for colon carcinogen 1,2-dimethylhydrazine.
- Author
-
Hori H, Shimoyoshi S, Tanaka Y, Momonami A, Masumura K, Yamada M, Fujii W, Kitagawa Y, and Hayashi M
- Subjects
- Animals, Bone Marrow Cells drug effects, Bone Marrow Cells metabolism, Bone Marrow Cells pathology, Colon drug effects, Colon metabolism, Colon pathology, Colonic Neoplasms chemically induced, Colonic Neoplasms genetics, Colonic Neoplasms metabolism, Hematopoietic Stem Cells drug effects, Hematopoietic Stem Cells metabolism, Hematopoietic Stem Cells pathology, Liver drug effects, Liver metabolism, Liver pathology, Male, Micronuclei, Chromosome-Defective drug effects, Mutation Rate, Organ Specificity, Rats, Rats, Inbred F344, Rats, Transgenic, 1,2-Dimethylhydrazine toxicity, Carcinogens toxicity, Chromosome Aberrations drug effects, Colonic Neoplasms diagnosis, Endpoint Determination, Mutagenicity Tests
- Abstract
Human risk assessment of the toxic potency of chemicals typically includes genotoxicity assays for predicting carcinogenicity. Gene mutation frequency and chromosomal aberration are two major genotoxicity endpoints in standardized in vitro and in vivo assays. The weight-of-evidence approach in risk assessment is more focused on in vivo assay results; however, animal welfare considerations are aimed at the reduction, replacement, and refinement (3R's) of animal experiments, including a reduction in the number of experimental animals. Proposals to reduce experimental animals in genotoxicity testing include the incorporation of genotoxicity endpoint(s) into other toxicological studies and the combination of two or more assays detecting different genotoxicity endpoints in the same animals. In this study, we used 1,2-dimethylhydrazine as a model chemical of colon carcinogen to assess gene mutation frequency and chromosomal aberration in vivo simultaneously. Specifically, a gene mutation frequency assay was combined with a multiple-organ micronucleus test (peripheral blood, bone marrow, liver, and colon) in F344 gpt delta transgenic rats. Both gpt mutant frequency and micronucleated cell frequency significantly increased in colon and liver but not in bone marrow. Interestingly, we found that the colon carcinogen induced both gene mutations and micronuclei in the targeted colon tissue. Thus, we demonstrated that the mechanism of a carcinogen could be derived from an animal experiment using a lower number of experimental animals as currently recommended. Moreover, a significant increase in mutant frequency in colon and liver was already observed on the first day after treatment completion, as well as on the third day, which is the guideline-recommended period. Thus, this endpoint is compatible with other genotoxicity assays. We confirmed that performing the micronucleus assay in combination with a gene mutation assay in F344 gpt delta transgenic rats is useful to evaluate different genotoxic endpoints simultaneously in the same animals, which reduces the number of experimental animals., Competing Interests: Declaration of Competing Interest The authors have no conflict of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
162. Domain swapping of complementarity-determining region in nanobodies produced by Pichia pastoris.
- Author
-
Miura N, Miyamoto K, Ohtani Y, Yaginuma K, Aburaya S, Kitagawa Y, Aoki W, and Ueda M
- Abstract
Easy preparation of chimeric nanobodies with various scaffolds is important for customizing abilities of nanobodies toward practical utilization. To accomplish high-throughput production of various nanobodies, utilization of microbes is an attractive option. In the present study, various chimeric nanobodies were prepared using the methylotrophic yeast Pichia pastoris. We designed chimeric nanobodies with complementarity-determining regions (CDRs) against green fluorescent protein (GFP) or cluster of differentiation 4 (CD4) based on the scaffold of GFP-nanobody. FLAG-tagged chimeric nanobodies were prepared by one-step cloning and produced using P. pastoris. Secreted chimeric nanobodies were purified from the culture media of P. pastoris transformants. Relative binding abilities of purified chimeric nanobodies to GFP and CD4 was tested using a BIACORE T-200. P. pastoris successfully produced a high yield of FLAG-tagged chimeric nanobodies. FLAG-tagged GFP- and CD4-nanobodies were shown to specifically bind to GFP and CD4, respectively. Chimeric nanobodies, in which the CDR2 or 3 of GFP-nanobody was replaced with CDRs of CD4-nanobody, acquired the ability to bind to CD4 without binding to GFP. These results demonstrate successful production of functional chimeric nanobodies using P. pastoris. These results also suggest that swapping of CDRs, especially CDRs 2 or 3, potentially enables a novel method of creating nanobodies.
- Published
- 2019
- Full Text
- View/download PDF
163. Sesame Lignans Suppress Age-Related Cognitive Decline in Senescence-Accelerated Mice.
- Author
-
Shimoyoshi S, Takemoto D, Ono Y, Kitagawa Y, Shibata H, Tomono S, Unno K, and Wakabayashi K
- Subjects
- Aging, Animals, Body Weight drug effects, Brain drug effects, Humans, Lignans administration & dosage, Male, Mice, Mice, Inbred Strains, Organ Size, Survival Analysis, Cognitive Dysfunction drug therapy, Lignans pharmacology, Sesamum chemistry
- Abstract
Sesame lignans, which are biologically active compounds present in sesame seeds and oil, are known to have neuroprotective effects in several models of brain dysfunction. However, the effects of sesame lignans on age-related brain dysfunction are not clear and were thus investigated in the present study using a senescence-accelerated mouse (SAMP10). Two-month-old male SAMP10 mice were administrated a basal diet with 0% or 0.05% sesame lignans for two months, or with 0%, 0.02%, or 0.05% sesame lignans for 10 months and subjected to step-through passive avoidance tasks and forced swim tests. Reactive carbonyl species (RCs) were evaluated as markers of oxidative stress using a recently developed comprehensive analytical method. Both learning time in passive avoidance tasks and immobile time in forced swim tests became longer with aging ( p < 0.05). However, the administration of sesame lignans significantly ameliorated age-related effects in both tests ( p < 0.05). Age-related increases in RCs such as 4-hydroxy-2-nonenal in the cerebral cortex and liver were reduced in mice fed sesame lignans. These results suggest that sesame lignans can prevent age-related brain dysfunction via anti-oxidative activity.
- Published
- 2019
- Full Text
- View/download PDF
164. System x c - in microglia is a novel therapeutic target for post-septic neurological and psychiatric illness.
- Author
-
Kitagawa Y, Nakaso K, Horikoshi Y, Morimoto M, Omotani T, Otsuki A, Inagaki Y, Sato H, and Matsura T
- Subjects
- Amino Acid Transport System y+ antagonists & inhibitors, Amino Acid Transport System y+ metabolism, Animals, Disease Models, Animal, Dizocilpine Maleate pharmacology, Excitatory Amino Acid Antagonists pharmacology, Female, Interleukin-1beta metabolism, Lipopolysaccharides toxicity, Male, Mental Disorders drug therapy, Mice, Mice, Inbred C57BL, Mice, Knockout, Nervous System Diseases drug therapy, Quinoxalines pharmacology, Sepsis psychology, Sulfasalazine pharmacology, Tumor Necrosis Factor-alpha metabolism, Amino Acid Transport System y+ genetics, Glutamic Acid metabolism, Mental Disorders etiology, Microglia metabolism, Nervous System Diseases etiology
- Abstract
Post-septic neurological and psychiatric illness (PSNPI) including dementia and depression may be observed after sepsis. However, the etiology of PSNPI and therapeutic treatment of PSNPI are unclear. We show that glutamate produced from microglia through the activity of system x
c - plays a role in PSNPI. We established a mouse model of PSNPI by lipopolysaccharide (LPS) treatment that shows a disturbance of short/working memory and depression-like hypoactivity. Glutamate receptor antagonists (MK801 and DNQX) reduced these phenotypes, and isolated microglia from LPS-treated mice released abundant glutamate. We identified system xc - as a source of the extracellular glutamate. xCT, a component of system xc - , was induced and expressed in microglia after LPS treatment. In xCT knockout mice, PSNPI were decreased compared to those in wildtype mice. Moreover, TNF-α and IL-1β expression in wildtype mice was increased after LPS treatment, but inhibited in xCT knockout mice. Thus, system xc - in microglia may be a therapeutic target for PSNPI. The administration of sulfasalazine, an inhibitor of xCT, in symptomatic and post-symptomatic mice improved PSNPI. Our results suggest that glutamate released from microglia through system xc - plays a critical role in the manifestations of PSNPI and that system xc - may be a therapeutic target for PSNPI.- Published
- 2019
- Full Text
- View/download PDF
165. Peptide barcoding for establishment of new types of genotype-phenotype linkages.
- Author
-
Miyamoto K, Aoki W, Ohtani Y, Miura N, Aburaya S, Matsuzaki Y, Kajiwara K, Kitagawa Y, and Ueda M
- Subjects
- Antibodies genetics, Antibodies immunology, Antibodies metabolism, Antigens genetics, Antigens immunology, CD4 Antigens genetics, CD4 Antigens immunology, Genotype, Humans, Peptides genetics, Peptides immunology, Phenotype, Pichia chemistry, Pichia genetics, Protein Binding immunology, Single-Domain Antibodies genetics, Single-Domain Antibodies immunology, Surface Plasmon Resonance, Nanotechnology, Peptides chemistry, Protein Binding genetics, Single-Domain Antibodies chemistry
- Abstract
Measuring binding properties of binders (e.g., antibodies) is essential for developing useful experimental reagents, diagnostics, and pharmaceuticals. Display technologies can evaluate a large number of binders in a high-throughput manner, but the immobilization effect and the avidity effect prohibit the precise evaluation of binding properties. In this paper, we propose a novel methodology, peptide barcoding, to quantitatively measure the binding properties of multiple binders without immobilization. In the experimental scheme, unique peptide barcodes are fused with each binder, and they represent genotype information. These peptide barcodes are designed to have high detectability for mass spectrometry, leading to low identification bias and a high identification rate. A mixture of different peptide-barcoded nanobodies is reacted with antigen-coated magnetic beads in one pot. Peptide barcodes of functional nanobodies are cleaved on beads by a specific protease, and identified by selected reaction monitoring using triple quadrupole mass spectrometry. To demonstrate proof-of-principle for peptide barcoding, we generated peptide-barcoded anti-CD4 nanobody and anti-GFP nanobody, and determined whether we could simultaneously quantify their binding activities. We showed that peptide barcoding did not affect the properties of the nanobodies, and succeeded in measuring the binding activities of these nanobodies in one shot. The results demonstrate the advantages of peptide barcoding, new types of genotype-phenotype linkages., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
- Full Text
- View/download PDF
166. Integration of micronucleus tests with a gene mutation assay in F344 gpt delta transgenic rats using benzo[a]pyrene.
- Author
-
Hori H, Shimoyoshi S, Tanaka Y, Momonami A, Masumura K, Yamada M, Fujii W, and Kitagawa Y
- Subjects
- Animals, Bone Marrow drug effects, Colon drug effects, Liver drug effects, Male, Rats, Rats, Inbred F344, Rats, Transgenic, Reticulocytes drug effects, Benzo(a)pyrene pharmacology, Carcinogens pharmacology, Micronuclei, Chromosome-Defective chemically induced, Micronucleus Tests methods, Mutagenicity Tests methods, Mutagens pharmacology, Transferases (Other Substituted Phosphate Groups) genetics
- Abstract
Reduction of the number of animals used in in vivo genotoxicity tests is encouraged. For this purpose, we conducted integrated toxicity tests combining gene mutation assays with multiple-organ micronucleus (MN) tests (peripheral blood, bone marrow, liver, and colon) in F344 gpt delta transgenic (Tg) rats. Seven-week-old male F344 gpt delta rats were orally administered 62.5 or 125 mg/kg/day benzo[a]pyrene (B[a]P) for 28 days. One day after the final day of treatment (day 29) and three days after the final treatment (day 31), bone marrow, liver, and colon samples were collected, and mutation assays and MN tests were performed. The gpt mutant frequency (MF) significantly increased in bone marrow, liver and colon but MN induction was only significant in bone marrow but not in liver and colon. Similarly MN induction was only observed in bone marrow in non-Tg F344 rats. In peripheral blood obtained on day 4, 15, 29, 31, a time-dependent increase was observed in reticulocyte MN frequency during the treatment. Thus, our integrated method successfully detected both gene mutations and MN induction caused by B[a]P. In addition, no significant differences were observed between sampling times (day 29 versus 31), suggesting that sampling on day 29 is also valid to evaluate gene mutations. On the other hand, MN results in bone marrow and peripheral blood were different depending on the sampling day. An appropriate sampling day should be designated according to which assays are integrated. We confirmed that integration of the MN test with a gene mutation assay using F344 gpt delta Tg rats is useful to evaluate different endpoints related to genotoxicity using the same animals and to reduce animal use., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
167. Nonstructural protein of severe fever with thrombocytopenia syndrome phlebovirus targets STAT2 and not STAT1 to inhibit type I interferon-stimulated JAK-STAT signaling.
- Author
-
Kitagawa Y, Sakai M, Shimojima M, Saijo M, Itoh M, and Gotoh B
- Subjects
- Cell Line, Cytoplasm metabolism, Host-Pathogen Interactions, Humans, Inclusion Bodies, Viral metabolism, Phlebovirus genetics, Phosphorylation, Viral Nonstructural Proteins genetics, Bunyaviridae Infections metabolism, Interferon-alpha metabolism, Phlebovirus metabolism, STAT2 Transcription Factor metabolism, Signal Transduction physiology, Viral Nonstructural Proteins metabolism
- Abstract
The nonstructural protein NSs of severe fever with thrombocytopenia syndrome phlebovirus blocks type I interferon (IFN)-stimulated JAK-STAT signaling. However, there is continuing controversy as to whether NSs targets STAT1 or STAT2 or both for this blockade. The present study was designed to gain a further understanding of the blockade mechanism. Immunoprecipitation experiments revealed a stronger interaction of NSs with STAT2 than with any other component constituting the JAK-STAT pathway. Expression of NSs resulted in the formation of cytoplasmic inclusion bodies (IBs), and affected cytoplasmic distribution of STAT2. STAT2 was relocated to NSs-induced IBs. Consequently, NSs inhibited IFN-α-stimulated tyrosine phosphorylation and nuclear translocation of STAT2. These inhibitory effects as well as the signaling blockade activity were not observed in NSs mutant proteins lacking the STAT2-binding ability. In contrast, NSs affected neither subcellular distribution nor phosphorylation of STAT1 in response to IFN-α and IFN-γ, demonstrating that NSs has little physical and functional interactions with STAT1. Taken together, these results suggest that NSs sequesters STAT2 into NSs-induced IBs, thereby blocking type I IFN JAK-STAT signaling., (Copyright © 2018 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
168. Mechanisms of chromosomal aberrations induced by sesamin metabolites in Chinese hamster lung cells.
- Author
-
Ono Y, Tomimori N, Hori H, Kitagawa Y, and Shibata H
- Subjects
- Animals, Bridged Bicyclo Compounds, Heterocyclic metabolism, Cell Culture Techniques, Cricetinae, Cyclooctanes metabolism, Dioxoles metabolism, Dose-Response Relationship, Drug, Glutathione metabolism, Hep G2 Cells, Humans, Lignans metabolism, Liver metabolism, Liver Extracts, Lung cytology, Lung drug effects, Bridged Bicyclo Compounds, Heterocyclic toxicity, Chromosome Aberrations chemically induced, Cyclooctanes toxicity, Dioxoles toxicity, Lignans toxicity
- Abstract
Sesamin is a major lignan in sesame seeds and oil. We previously demonstrated that sesamin induces chromosomal aberrations (CA) in Chinese hamster lung (CHL/IU) cells in the presence of a metabolic activation system (S9 mix), although no genotoxicity was detected in vivo. To clarify the mechanism of CA induction by sesamin, we identified its principal active metabolite. A mono-catechol derivative, [2-(3,4-methylenedioxyphenyl)-6-(3,4-dihydroxyphenyl)-3,7-dioxabi-cyclo[3.3.0]octane (SC-1)], was previously identified in culture medium when sesamin was incubated with S9 mix. In the present study, we show that SC-1 induces CA in CHL/IU cells but not in human hepatoblastoma (HepG2) cells. SC-1 was unstable in culture medium. Addition of glutathione (GSH) to the incubation mixture decreased the rate of decomposition and also suppressed induction of CA in CHL/IU cells. These results indicate that SC-1 itself may not contribute to the induction of CA. Two GSH adducts of SC-1 were identified when SC-1 was incubated with GSH, suggesting that SC-1 was converted to the semiquinone/quinone form and then conjugated with GSH in the culture medium. Sodium sulfite (a quinone-responsive compound) also suppressed CA induction by SC-1. These findings strongly suggest that SC-1 is oxidized to semiquinone/quinone derivatives extracellularly in culture medium, that these derivatives are responsible for the induction of CA in CHL/IU cells, and therefore that the positive results obtained with sesamin in in vitro CA tests using CHL/IU cells may not be relevant to the assessment of in vivo activity., (Copyright © 2017 Elsevier B.V. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
169. Induction of necroptotic cell death by viral activation of the RIG-I or STING pathway.
- Author
-
Schock SN, Chandra NV, Sun Y, Irie T, Kitagawa Y, Gotoh B, Coscoy L, and Winoto A
- Subjects
- Amino Acid Chloromethyl Ketones pharmacology, Animals, Apoptosis drug effects, Cell Line, Cysteine Endopeptidases chemistry, Cysteine Endopeptidases genetics, Cysteine Endopeptidases metabolism, DEAD Box Protein 58 antagonists & inhibitors, DEAD Box Protein 58 genetics, Deubiquitinating Enzyme CYLD, Lung metabolism, Lung pathology, Membrane Proteins antagonists & inhibitors, Membrane Proteins genetics, Mice, Mice, Inbred C57BL, Mice, Knockout, Necrosis, RNA Interference, RNA, Small Interfering metabolism, Receptor-Interacting Protein Serine-Threonine Kinases antagonists & inhibitors, Receptor-Interacting Protein Serine-Threonine Kinases genetics, Receptor-Interacting Protein Serine-Threonine Kinases metabolism, Signal Transduction drug effects, Tumor Necrosis Factor-alpha pharmacology, Ubiquitination drug effects, Viral Proteins genetics, Viral Proteins metabolism, Virus Activation, DEAD Box Protein 58 metabolism, Gammaherpesvirinae physiology, Membrane Proteins metabolism, Sendai virus physiology
- Abstract
Necroptosis is a form of necrotic cell death that requires the activity of the death domain-containing kinase RIP1 and its family member RIP3. Necroptosis occurs when RIP1 is deubiquitinated to form a complex with RIP3 in cells deficient in the death receptor adapter molecule FADD or caspase-8. Necroptosis may play a role in host defense during viral infection as viruses like vaccinia can induce necroptosis while murine cytomegalovirus encodes a viral inhibitor of necroptosis. To see how general the interplay between viruses and necroptosis is, we surveyed seven different viruses. We found that two of the viruses tested, Sendai virus (SeV) and murine gammaherpesvirus-68 (MHV68), are capable of inducing dramatic necroptosis in the fibrosarcoma L929 cell line. We show that MHV68-induced cell death occurs through the cytosolic STING sensor pathway in a TNF-dependent manner. In contrast, SeV-induced death is mostly independent of TNF. Knockdown of the RNA sensing molecule RIG-I or the RIP1 deubiquitin protein, CYLD, but not STING, rescued cells from SeV-induced necroptosis. Accompanying necroptosis, we also find that wild type but not mutant SeV lacking the viral proteins Y1 and Y2 result in the non-ubiquitinated form of RIP1. Expression of Y1 or Y2 alone can suppress RIP1 ubiquitination but CYLD is dispensable for this process. Instead, we found that Y1 and Y2 can inhibit cIAP1-mediated RIP1 ubiquitination. Interestingly, we also found that SeV infection of B6 RIP3
-/- mice results in increased inflammation in the lung and elevated SeV-specific T cells. Collectively, these data identify viruses and pathways that can trigger necroptosis and highlight the dynamic interplay between pathogen-recognition receptors and cell death induction.- Published
- 2017
- Full Text
- View/download PDF
170. Evaluation of single-dose RBC Pig-a and PIGRET assays in detecting the mutagenicity of thiotepa in rats.
- Author
-
Tsutsumi E, Momonami A, Hori H, and Kitagawa Y
- Subjects
- Animals, Body Weight drug effects, Male, Rats, Rats, Sprague-Dawley, Erythrocytes drug effects, Membrane Proteins genetics, Mutagenicity Tests methods, Mutagens toxicity, Reticulocytes drug effects, Thiotepa toxicity
- Abstract
The Pig-a assay, which uses reticulocytes (PIGRET assay) as target cells, is anticipated to detect mutagenicity at earlier time points than the RBC Pig-a assay, which uses all red blood cells as target cells. As part of a collaborative study conducted by the Mammalian Mutagenicity Study (MMS) Group, we evaluated the PIGRET and RBC Pig-a assays to detect Pig-a gene mutations induced by the carcinogen thiotepa. A single dose of thiotepa at 7.5, 15, and 30mg/kg was administered to 8-week-old male Sprague-Dawley rats by oral gavage. PIGRET and RBC Pig-a assays were performed using peripheral blood collected from rats 7, 14, and 28days after thiotepa administration (Day 0 as the day of administration), and the resulting Pig-a mutant frequencies (MFs) were compared. Increased Pig-a MF was observed from Day 7 onwards using the PIGRET assay. Pig-a MF remained fairly constant thereafter until Day 28 in the 30mg/kg group, whereas it peaked on Day 14 in the 7.5 and 15mg/kg groups. Using the RBC Pig-a assay, on the other hand, no significant increase in MF was observed at any of the dosages on Days 7, 14, or 28. These findings show that Pig-a gene mutations following a single dose of thiotepa were detected using the PIGRET assay but not the RBC Pig-a assay, which suggests that PIGRET assay is more suitable than RBC Pig-a assay for evaluating the in vivo mutagenicity by a single dose., (Copyright © 2016. Published by Elsevier B.V.)
- Published
- 2016
- Full Text
- View/download PDF
171. Nicotine enhances the malignant potential of human pancreatic cancer cells via activation of atypical protein kinase C.
- Author
-
Hanaki T, Horikoshi Y, Nakaso K, Nakasone M, Kitagawa Y, Amisaki M, Arai Y, Tokuyasu N, Sakamoto T, Honjo S, Saito H, Ikeguchi M, Yamashita K, Ohno S, and Matsura T
- Subjects
- Animals, Cell Line, Cell Line, Tumor, Cell Membrane drug effects, Cell Membrane metabolism, Cell Movement drug effects, Cell Proliferation drug effects, Humans, Male, Mice, Mice, Inbred BALB C, Neoplasm Invasiveness, Nicotine toxicity, Phosphatidylinositol 3-Kinases metabolism, Signal Transduction, Smoking adverse effects, Nicotine pharmacology, Pancreatic Neoplasms metabolism, Protein Kinase C metabolism
- Abstract
Background: Pancreatic cancer (PC) is the most lethal malignancy among solid tumors, and the most common risk factor for its development is cigarette smoking. Atypical protein kinase C (aPKC) isozymes function in cell polarity, proliferation, and survival, and have also been implicated in carcinogenesis. However, the involvement of aPKC in PC progression and the effect of nicotine, a major component of cigarette smoke, on the biological activities of aPKC remain to be fully elucidated., Methods: We investigated the effects of nicotine on the proliferation, migration and invasion of the human PC cell lines Panc1 and BxPC3. We analyzed aPKC localization and activity by immunohistochemistry and in vitro kinase assays, respectively, to assess their involvement in the regulation of PC progression. Moreover, we examined the effect of nicotine on implanted peritoneal tumors of PC cells in mice., Results: Nicotine enhanced cell proliferation, migration and invasion in Panc1 and BxPC3 cells. In nicotine-treated PC cells, the aPKC was significantly activated. We also found that nicotine induced phosphatidylinositol 3-kinase (PI3K) signal activation, and a specific inhibitor of the nicotine acetylcholine receptor (nAChR) as well as knockdown of nAChR prevented nicotine-mediated Akt phosphorylation and aPKC activation. In a peritoneal dissemination model of PC, nicotine-treated mice had larger tumors and increased numbers of nodules. Immunohistochemistry showed enhanced expression levels of aPKC and phosphorylated Akt in nodules from nicotine-treated mice., Conclusions and General Significance: Nicotine induces aberrant activation of aPKC via nAChR/PI3K signaling in PC cells, resulting in enhancement of cellular proliferation, migration and invasion., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
172. Rice Bran Dietary Supplementation Improves Neurological Symptoms and Loss of Purkinje Cells in Vitamin E-Deficient Mice.
- Author
-
Takahashi T, Nakaso K, Horikoshi Y, Hanaki T, Yamakawa M, Nakasone M, Kitagawa Y, Koike T, and Matsura T
- Abstract
Background: Vitamin E (VE, α-tocopherol) is a fat-soluble vitamin and is well known as an antioxidant. A deficiency in VE induces oxidative stress in the brain and causes motor and memory dysfunction. The consumption of a VE-rich diet has been given much attention in recent years, in regards to anti-aging and the prevention of age-related neuronal disorders., Methods: A VE-deficient mouse model was prepared by feeding the animals a diet lacking VE. In addition, to evaluate the effect of VE-containing rice bran (RB) on VE deficiency, a diet including RB was also provided. VE levels in the brain tissue, as well as in the RB, were measured using an HPLC system. Behavioral tests, including rotarod, wheel running activity, Y-maze, and elevated plus maze were performed. To clarify the effect of VE deficiency and RB, we investigated the induction of heme oxygenase-1 (HO-1). Histological studies were performed using HE staining and immunohistochemical studies were performed using antibodies against glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba1)., Results: VE in the mouse brain under a VE-deficient diet was decreased, and recovered α-tocopherol levels were observed in the brain of mice fed an RB diet. Motor behavioral scores were decreased in VE-deficient conditions, while the supplementation of RB improved motor function. HO-1, a marker of oxidative stress, was upregulated in the mouse brain under VE deficiency, however, RB supplementation inhibited the increase of HO-1. Histological analyses showed neuronal degeneration of Purkinje cells and decreased GFAP-immunoreactivity of Bergmann glia in the cerebellum. In addition, activated astrocytes and microglia were observed in mice fed the VE-deficient diet. Mice fed the RB diet showed improvement in these histological abnormalities., Conclusion: A VE-deficient diet induced motor dysfunction in mice due to the degeneration of Purkinje cells in the cerebellum. Oral supplementation of RB increases VE in the brain and improved the motor dysfunction caused by VE deficiency. Thus, RB or unpolished rice may be a promising VE supplement.
- Published
- 2016
173. Preconditioning by Low Dose LPS Prevents Subsequent LPS-Induced Severe Liver Injury via Nrf2 Activation in Mice.
- Author
-
Nakasone M, Nakaso K, Horikoshi Y, Hanaki T, Kitagawa Y, Takahashi T, Inagaki Y, and Matsura T
- Abstract
Background: Sepsis is a syndrome triggered by endotoxin lipopolysaccharide (LPS) during bacterial infection. Sepsis sometimes recurs, with the second sepsis giving rise to a different phenotype because of disease modification by the preceding sepsis. Such a protective modification is called a preconditioning (PC) effect. PC is an endogenous protective mechanism by which sublethal damage confers tolerance to a subsequent lethal load. Oxidative stress is one of the important pathogenetic mechanisms that occur in sepsis. The nuclear factor erythroid 2 (NF-E2)-related factor-2 (Nrf2) system is a key regulatory transcription factor that protects organs and cells against oxidative stress and may be associated with the PC effect in repeated sepsis., Methods: The effect of PC induced by low-dose LPS on survival rate and liver injury against subsequent high-dose LPS stimulation was examined using a mouse model of sepsis. In order to understand the detailed mechanism(s) involved in the PC effect within the liver, gene expression array was performed. As a candidate mechanism of PC, the activation of the Nrf2 system was analyzed using Nrf2 reporter mice. Furthermore, the induction of heme oxygenase-1 (HO-1), one of the main targets of Nrf2, in the liver was examined by immunoblotting and immunohistochemistry. The PC effect on liver injury induced by LPS was further examined using Nrf2-deficient mice., Results: PC by LPS (1.7 or 5.0 mg/kg body weight, intraperitoneally) increased the survival rate of mice and decreased liver injury in response to a subsequent injection of a lethal level of LPS (20 mg/kg body weight). DNA array revealed that the gene ontology term "antioxidant activity" as one of the candidate mechanisms of the PC effect by LPS. In Nrf2 reporter mice, PC immediately and intensely enhanced luminescence that indicated Nrf2 activation after subsequent LPS injection. The induction of HO-1 by LPS was also enhanced by preceding PC, and its induction was observed mainly in Kupffer cells of the liver. In Nrf2-deficient mice, the induction of HO-1 in Kupffer cells and the hepatoprotective effect of PC were decreased as compared with wild-type mice., Conclusion: Our results suggest that activation of the Nrf2 system is, at least in part, one of the mechanisms of a PC effect in the mouse liver in the case of repeated LPS stimulation.
- Published
- 2016
174. Effects of ADH1B and ALDH2 Genetic Polymorphisms on Alcohol Elimination Rates and Salivary Acetaldehyde Levels in Intoxicated Japanese Alcoholic Men.
- Author
-
Yokoyama A, Kamada Y, Imazeki H, Hayashi E, Murata S, Kinoshita K, Yokoyama T, and Kitagawa Y
- Subjects
- Asian People genetics, Genetic Predisposition to Disease genetics, Genotype, Humans, Male, Acetaldehyde metabolism, Alcohol Dehydrogenase genetics, Alcoholic Intoxication genetics, Alcoholic Intoxication metabolism, Aldehyde Dehydrogenase, Mitochondrial genetics, Ethanol metabolism, Polymorphism, Genetic, Saliva metabolism
- Abstract
Background: The genetic polymorphisms of alcohol dehydrogenase-1B (ADH1B) and aldehyde dehydrogenase-2 (ALDH2) are associated with the risk of alcoholism and upper aerodigestive tract cancer in alcoholics. Salivary ethanol (sEtOH) levels are well correlated with blood EtOH levels., Methods: To study the effects of ADH1B and ALDH2 genotypes on the alcohol elimination rate (AER) and salivary acetaldehyde (sAcH) levels, we measured the sEtOH and sAcH levels twice at a 1-hour intervals in 99 intoxicated Japanese alcoholic men who had stopped drinking for 4 or more hours., Results: The initial sEtOH levels did not differ between the ADH1B*2 group (n = 50) and the ADH1B*1/*1 group (n = 49) (median: 0.617 vs. 0.762 mg/ml). The salivary AER (sAER) increased as the sEtOH levels increased (p < 0.0001). After stratification according to the sEtOH levels (<0.4, 0.4 to 0.99, and ≥1.00 mg/ml), the median sAER of the ADH1B*2 group was 0.075, 0.188, and 0.228 mg/ml/h, respectively, and that of the ADH1B*1/*1 group was 0.037, 0.115, and 0.233 mg/ml/h, respectively. The sAER of the ADH1B*2 group was faster than that of the ADH1B*1/*1 group overall (p = 0.001) and when the sEtOH category was 0.4 to 0.99 mg/ml (p < 0.0001). The ADH1B genotype and the sEtOH levels had an interaction effect on the sAER (p = 0.036). A multiple linear regression analysis with a stepwise procedure selected the ADH1B*2 allele (p = 0.004) and the sEtOH levels (p < 0.0001) as positive predictors of sAER. The sAER did not differ according to the ALDH2 genotype. The sAcH levels were higher than the blood AcH levels reported in alcoholics, probably because of AcH production by oral microorganisms. The sAcH of the ALDH2*1/*2 group (n = 18) was higher than that of the ALDH2*1/*1 group (n = 81) overall (p = 0.0008) and when the corresponding sEtOH category was ≥1.00 mg/ml (median: 3.195 vs. 1.776 μg/ml, p = 0.009). A multiple linear regression analysis selected the ALDH2*1/*2 and the sEtOH levels as positive predictors of the sAcH levels (p < 0.0001)., Conclusions: The enhanced AER in ADH1B*2 carriers and the increased sAcH levels in ALDH2*1/*2 carriers among intoxicated alcoholics provide possible mechanisms explaining how each genetic polymorphism affects the risk of alcoholism and upper aerodigestive tract cancer., (Copyright © 2016 by the Research Society on Alcoholism.)
- Published
- 2016
- Full Text
- View/download PDF
175. Relationship between coumarin-induced hepatocellular toxicity and mitochondrial function in rats.
- Author
-
Tanaka Y, Fujii W, Hori H, Kitagawa Y, and Ozaki K
- Subjects
- Aconitate Hydratase metabolism, Animals, Coumarins administration & dosage, Dose-Response Relationship, Drug, Drug Administration Schedule, Glutathione metabolism, Male, Necrosis metabolism, Rats, Rats, Sprague-Dawley, Chemical and Drug Induced Liver Injury pathology, Coumarins toxicity, Mitochondria, Liver drug effects, Necrosis chemically induced
- Abstract
The manifestation of coumarin-induced hepatocellular toxicity may differ and depends on the frequency of administration to rats. A single coumarin dose induces hepatocellular necrosis while repeated doses induce only hepatocyte degeneration. However, the mechanism underlying these effects remains unclear. Therefore, we investigated the mechanism of coumarin-induced hepatotoxicity in rats. Coumarin was administered to male rats as a single dose or for 4 consecutive days, and samples were obtained 4 or 24 h after a single dose or 24 h after the repeated doses. A single coumarin dose significantly induced hepatocellular necrosis in rats; however, toxicity was attenuated after repeated dosing. With a single dose, hepatocellular necrosis was preceded by increased mitochondrial number and size and decreased mitochondrial function. An increased expression of granular cytochrome P450 (CYP) 2E1 protein was observed in the cytoplasm and mitochondria of coumarin-treated rats compared to the expression in the untreated controls. Nevertheless, repeated dosing showed mitochondrial function that was equivalent to that of the control while enlarged CYP2E1 protein droplets were distributed outside the mitochondria. These results suggest that mitochondrial function and CYP2E1 expression might be involved in coumarin-induced hepatocellular toxicity in rats. A reduction in mitochondrial CYP2E1 might be implicated in the acquisition of coumarin resistance after repeated doses., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
176. Estrogen receptor-mediated effect of δ-tocotrienol prevents neurotoxicity and motor deficit in the MPTP mouse model of Parkinson's disease.
- Author
-
Nakaso K, Horikoshi Y, Takahashi T, Hanaki T, Nakasone M, Kitagawa Y, Koike T, and Matsura T
- Subjects
- Animals, Estrogen Receptor alpha metabolism, Female, Male, Mice, Inbred C57BL, Motor Skills, Parkinson Disease etiology, Parkinson Disease physiopathology, Vitamin E therapeutic use, 1-Methyl-4-phenylpyridinium, Estrogen Receptor beta metabolism, Neuroprotective Agents therapeutic use, Parkinson Disease drug therapy, Vitamin E analogs & derivatives
- Abstract
Neuroprotection following signal transduction has been investigated recently as a strategy for Parkinson's disease (PD) therapy. While oxidative stress is important in the pathogenesis of PD, neuroprotection using antioxidants such as α-tocopherol have not been successful. δ-tocotrienol (δT3), a member of the vitamin E family, has received attention because of activities other than its antioxidative effects. In the present study, we examined the estrogen receptor-β (ERβ)-mediated neuroprotective effects of δT3 in a mouse model of PD. ERβ is expressed in neuronal cells, including dopaminergic neurons in the substantia nigra. Daily forced oral administration of δT3 inhibited the loss of dopaminergic neurons in the substantia nigra. In addition, the ER inhibitor tamoxifen canceled the neuroprotective effects of δT3. Moreover, δT3 administration improved the performance of the PD mice in the wheel running activity, while tamoxifen inhibited this improved performance. These results suggest that the oral administration of δT3 may be useful in the treatment of PD patients, and ERβ may be a candidate target for the neuroprotection activity of δT3., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
177. Pharmacokinetics and safety of the sesame lignans, sesamin and episesamin, in healthy subjects.
- Author
-
Tomimori N, Tanaka Y, Kitagawa Y, Fujii W, Sakakibara Y, and Shibata H
- Subjects
- Adult, Dioxoles adverse effects, Dioxoles blood, Female, Humans, Lignans adverse effects, Lignans blood, Male, Middle Aged, Young Adult, Dioxoles pharmacokinetics, Lignans pharmacokinetics, Sesamum
- Abstract
A single-blind, placebo-controlled, parallel-group and multiple oral dose study was conducted in 48 healthy subjects to investigate the pharmacokinetics and safety of multiple oral doses of sesame lignans (sesamin and episesamin). Subjects were randomly divided into two groups. Each subject was administered 50 mg of sesame lignans (sesamin/episesamin=1/1) or placebo once daily for 28 days. The pharmacokinetics of the sesame lignans were investigated using 10 of the 24 subjects in the sesame lignans group. No serious adverse events were observed in this study. Sesamin was absorbed with a peak plasma concentration at 5.0 h. The plasma concentration of the main metabolite, SC-1, reached a peak at 5.0 h and decreased rapidly with a terminal half-life of 2.4 h. Episesamin was also absorbed with a peak plasma concentration at 5.0 h and decreased with a terminal half-life of 7.1 h. The plasma concentration of the main metabolite, EC-1, reached a peak at 5.0 h and decreased rapidly with a terminal half-life of 3.4 h. The plasma concentrations of sesamin and episesamin reached a steady state by day 7. Sesame lignans were confirmed to be safe and tolerable in healthy subjects. The results of the pharmacokinetic study demonstrate that no accumulation was observed following multiple 50 mg doses of sesame lignans., (Copyright © 2013 John Wiley & Sons, Ltd.)
- Published
- 2013
- Full Text
- View/download PDF
178. Expeditious neutralization assay for human metapneumovirus based on a recombinant virus expressing Renilla luciferase.
- Author
-
Zhou M, Kitagawa Y, Yamaguchi M, Uchiyama C, Itoh M, and Gotoh B
- Subjects
- Humans, Luciferases analysis, Luciferases genetics, Metapneumovirus genetics, Antibodies, Neutralizing blood, Antibodies, Viral blood, Metapneumovirus immunology, Neutralization Tests methods
- Abstract
Background: Human metapneumovirus (HMPV) is a common cause of respiratory diseases in persons of all ages. Because of its slow replication and weak cytopathic effect in cultured cells, conventional neutralization assays for HMPV require around one week for completion., Objectives: The purpose of this study is to establish a rapid neutralization assay based on a recombinant virus expressing Renilla luciferase (Rluc)., Study Design: A recombinant HMPV expressing both Rluc and green fluorescent protein (GFP) was created by reverse genetics method. Two-fold serial dilutions of human 23 sera were made in a 96-well plate and incubated with 50 pfu/well of the recombinant virus at 4°C for 1 h. The mixtures were then transferred to LLC-MK2 cells in a 96-well plate, incubated for 2 h, and replaced with trypsin-free fresh media. After incubation at 32°C for 24 h, the cells were lysed and measured for Rluc activity. The neutralization titer was defined as the reciprocal of the highest serum dilution that resulted in 50% reduction of Rluc activity., Results: The novel assay could be completed within 24 h and eliminated the requirement of trypsin supporting multistep replication in cultured cells, as well as laborious processes including the plaque assay with immunostaining. Neutralization titers correlated well with those determined by a GFP-based assay previously developed., Conclusions: The neutralization assay based on Rluc activity is the fastest and the most straightforward of all previous assays, and may be available for high throughput screening of neutralizing antibodies., (Copyright © 2012 Elsevier B.V. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
179. Involvement of heme oxygenase-1 induction via Nrf2/ARE activation in protection against H2O2-induced PC12 cell death by a metabolite of sesamin contained in sesame seeds.
- Author
-
Hamada N, Tanaka A, Fujita Y, Itoh T, Ono Y, Kitagawa Y, Tomimori N, Kiso Y, Akao Y, Nozawa Y, and Ito M
- Subjects
- Animals, Dioxoles chemistry, Dioxoles pharmacology, Heme Oxygenase-1 chemistry, Lignans chemistry, Lignans pharmacology, PC12 Cells, Rats, Seedlings chemistry, Apoptosis, Dioxoles metabolism, Heme Oxygenase-1 metabolism, Hydrogen Peroxide metabolism, Lignans metabolism, NF-E2-Related Factor 2 metabolism, Sesamum chemistry
- Abstract
Induction of phase II antioxidant enzymes by activation of Nrf2/ARE (antioxidant response element) signaling has been considered as a promising strategy to combat with oxidative stress-related diseases. In the present study, we tested for potential effects of sesamin, a major lignan contained in sesame seeds, its stereoisomer episesamin, and their metabolites on Nrf2/ARE activation in rat pheochromocytoma PC12 cells. Luciferase reporter assays showed that primary metabolites of sesamin and episesamin, SC-1 and EC-1 were the most potent ARE activators among all tested compounds. SC-1 {(1R,2S,5R,6S)-6-(3,4-dihydroxyphenyl)-2-(3,4-methylenedioxyphenyl)-3,7-dioxabicyclo-[3,3,0]octane} enhanced nuclear translocation of Nrf2 and up-regulated expression of phase II antioxidant enzymes including heme oxygenase-1 (HO-1). Treatment with SC-1 resulted in increased phosphorylation of p38 MAP kinase and transient increase in intracellular ROS levels. N-acetylcysteine (NAC) treatment abolished p38 phosphorylation as well as HO-1 induction caused by SC-1, indicating that ROS are upstream signals of p38 in Nrf2/ARE activation by SC-1. Furthermore, preconditioning with SC-1 attenuated H(2)O(2)-induced cell death in a dose-dependent manner. Finally, treatment with a HO-1 inhibitor, Zn-protoporphyrin (ZnPP), and overexpression of a dominant-negative mutant of Nrf2 diminished SC-1-mediated neuroprotection. Our results demonstrate that SC-1 is capable of protecting against oxidative stress-induced neuronal cell death in part through induction of HO-1 via Nrf2/ARE activation, suggesting its potential to reduce oxidative stress and ameliorate oxidative stress-related neurodegenerative diseases., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
180. Genotoxicity evaluation of sesamin and episesamin.
- Author
-
Hori H, Takayanagi T, Kamada Y, Shimoyoshi S, Ono Y, Kitagawa Y, Shibata H, Nagao M, Fujii W, and Sakakibara Y
- Subjects
- Animals, Bone Marrow Cells drug effects, Bone Marrow Cells metabolism, Cells, Cultured, Chromosome Aberrations drug effects, Comet Assay, Cricetinae, Cricetulus, Dioxoles chemistry, Dioxoles toxicity, Dose-Response Relationship, Drug, Erythrocytes drug effects, Erythrocytes metabolism, Lignans chemistry, Lignans toxicity, Liver Extracts metabolism, Liver Extracts pharmacology, Male, Mice, Mice, Inbred ICR, Micronucleus Tests, Microsomes, Liver metabolism, Molecular Structure, Mutagenicity Tests, Mutation drug effects, Rats, Rats, Sprague-Dawley, Salmonella typhimurium drug effects, Salmonella typhimurium genetics, Sesame Oil chemistry, DNA Damage, Dioxoles pharmacology, Lignans pharmacology
- Abstract
Sesamin is a major lignan that is present in sesame seeds and oil. Sesamin is partially converted to its stereoisomer, episesamin, during the refining process of non-roasted sesame seed oil. We evaluated the genotoxicity of these substances through the following tests: a bacterial reverse mutation assay (Ames test), a chromosomal aberration test in cultured Chinese hamster lung cells (CHL/IU), a bone marrow micronucleus (MN) test in Crlj:CD1 (ICR) mice, and a comet assay using the liver of Sprague-Dawley (SD) rats. Episesamin showed negative results in the Ames test with and without S9 mix, in the in vitro chromosomal aberration test with and without S9 mix, and in the in vivo comet assay. Sesamin showed negative results in the Ames test with and without S9 mix. In the in vitro chromosomal aberration test, sesamin did not induce chromosomal aberrations in the absence of S9 mix, but induced structural abnormalities at cytotoxic concentrations in the presence of S9 mix. Oral administration of sesamin at doses up to 2.0g/kg did not cause a significant increase in either the percentage of micronucleated polychromatic erythrocytes in the in vivo bone marrow MN test or in the % DNA in the comet tails in the in vivo comet assay of liver cells. These findings indicate that sesamin does not damage DNA in vivo and that sesamin and episesamin have no genotoxic activity., (Copyright © 2010 Elsevier B.V. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
181. Genetic polymorphisms of the renin-angiotensin system and obesity-related metabolic changes in response to low-energy diets in obese women.
- Author
-
Hamada T, Kotani K, Nagai N, Tsuzaki K, Sano Y, Matsuoka Y, Fujibayashi M, Kiyohara N, Tanaka S, Yoshimura M, Egawa K, Kitagawa Y, Kiso Y, Moritani T, and Sakane N
- Subjects
- Adult, Caloric Restriction, Carbohydrate Metabolism genetics, Cholesterol, LDL blood, Cholesterol, LDL genetics, Female, Genotype, Humans, Lipid Peroxidation genetics, Middle Aged, Obesity diet therapy, Obesity metabolism, Renin-Angiotensin System genetics, Adipose Tissue metabolism, Blood Pressure genetics, Diet, Reducing, Obesity genetics, Peptidyl-Dipeptidase A genetics, Polymorphism, Genetic, Receptor, Angiotensin, Type 2 genetics
- Abstract
Objective: Genetic polymorphisms of the renin-angiotensin system have been implicated in cardiovascular and metabolic diseases. The purpose of this study was to investigate whether the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene and 3123C/A polymorphism of the angiotensin II type 2 receptor (AT(2)R) gene affect blood pressure and other obesity-related metabolic changes in response to low-energy diets using meal replacement shakes for weight loss., Methods: Clinical, metabolic, and biochemical profiles were measured before and after a 2-mo intervention in 32 obese women (age 49.9 ± 8.4 [SD] y; BMI 28.4 ± 3.3 kg/m²) restricted to 1200 kcal/d (5021 kJ/d). The polymorphisms were determined with an intercalater-mediated FRET probe assay system., Results: Although weight loss and nutrient intake levels did not differ among the genotypes, the reduction in body fat after weight loss was significantly less in the ACE deletion/deletion (D/D) genotype than insertion/insertion (I/I) plus I/D genotype (-2.25 ± 1.40% versus -0.80 ± 1.57%, P < 0.05). The AT₂R A/A group had significantly less improved levels of systolic blood pressure (-7.23 ± 8.50 versus 2.50 ± 12.6 mmHg, P < 0.05), low-density lipoprotein-cholesterol (-0.36 ± 0.29 versus -0.09 ± 0.25 mmol/L, P < 0.05), carbohydrate (-54.4 ± 27.2 versus -31.8 ± 16.3 mg/min, P < 0.05) and fat oxidation (8.31 ± 11.86 versus 0.05 ± 9.99 mg/min, P < 0.05) than the C/C plus C/A genotypes., Conclusion: The present findings suggest that the homozygous form of the ACE gene may hinder the improvement of body fat and that the homozygous form of the AT₂R gene may make improving systolic blood pressure and some obesity-related metabolic parameters through a dietary intervention difficult among obese women., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
182. Effect of intranasal administration of Lactobacillus pentosus S-PT84 on influenza virus infection in mice.
- Author
-
Izumo T, Maekawa T, Ida M, Noguchi A, Kitagawa Y, Shibata H, Yasui H, and Kiso Y
- Subjects
- Administration, Intranasal, Animals, Bronchoalveolar Lavage Fluid virology, Female, Interferon-gamma analysis, Interleukin-12 analysis, Killer Cells, Natural immunology, Lung immunology, Lung microbiology, Lymph Nodes immunology, Lymph Nodes virology, Mediastinum virology, Mice, Mice, Inbred BALB C, Orthomyxoviridae Infections immunology, Influenza A Virus, H1N1 Subtype, Lactobacillus immunology, Orthomyxoviridae Infections therapy, Th1 Cells immunology
- Abstract
Lactobacillus pentosus strain S-PT84 isolated from Kyoto pickles enhances splenic natural killer (NK) cell activity and exhibit anti-allergic effects by modulating the Th1/Th2 (T-helper1/T-helper2) balance. In the present study, we investigated whether the immune response could be activated by intranasal administration of S-PT84 in the respiratory immune system and protected against influenza virus infection in mice. When BALB/c mice received intranasal administration of S-PT84 once daily for 3 consecutive days, S-PT84 strongly induced interleukin-12 (IL-12) and gamma interferon (IFN-gamma) production in mediastinal lymph node (MLN) cells. At intranasal infection with influenza virus PR8 (a mouse-adapted H1N1 strain) after S-PT84 treatment, the survival rates of mice improved in a dose-dependent manner, and the titer of influenza virus in bronchoalveolar lavage fluids (BALF) was significantly decreased by S-PT84 administration. Production of IL-12 and alpha-interferon (IFN-alpha) in BALF were significantly higher in mice treated with S-PT84 compared to the control mice. Lung NK activity was also significantly augmented in S-PT84-treated mice. These results suggested that the L. pentosus strain S-PT84 showed inhibitory activity against influenza virus infection., ((c) 2010 Elsevier B.V. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
183. Covalent bonded Gag multimers in human immunodeficiency virus type-1 particles.
- Author
-
Kitagawa Y, Maeda-Sato M, Tanaka K, Tobiume M, Sawa H, Hasegawa H, Kojima A, Hall WW, Kurata T, Sata T, and Takahashi H
- Subjects
- Animals, Cell Line, Electrophoresis, Polyacrylamide Gel, HIV-1 genetics, HIV-1 physiology, Humans, Oxidation-Reduction, Protein Conformation, Protein Multimerization, RNA, Viral chemistry, Ribonuclease, Pancreatic metabolism, Virion chemistry, Virion genetics, Virus Replication, gag Gene Products, Human Immunodeficiency Virus genetics, HIV-1 chemistry, gag Gene Products, Human Immunodeficiency Virus chemistry
- Abstract
The oligomerization of HIV-1 Gag and Gag-Pol proteins, which are assembled at the plasma membrane, leads to viral budding. The budding generally places the viral components under non-reducing conditions. Here the effects of non-reducing conditions on Gag structures and viral RNA protection were examined. Using different reducing conditions and SDS-PAGE, it was shown that oligomerized Gag possesses intermolecular covalent bonds under non-reducing conditions. In addition, it was demonstrated that the mature viral core contains a large amount of covalent bonded Gag multimers, as does the immature core. Viral genomic RNA becomes sensitive to ribonuclease in reducing conditions. These results suggest that, under non-reducing conditions, covalent bonded Gag multimers are formed within the viral particles and play a role in protection of the viral genome.
- Published
- 2009
- Full Text
- View/download PDF
184. Metabolites of sesamin, a major lignan in sesame seeds, induce neuronal differentiation in PC12 cells through activation of ERK1/2 signaling pathway.
- Author
-
Hamada N, Fujita Y, Tanaka A, Naoi M, Nozawa Y, Ono Y, Kitagawa Y, Tomimori N, Kiso Y, and Ito M
- Subjects
- Animals, Antioxidants pharmacology, Cell Differentiation drug effects, Cell Differentiation physiology, Dioxoles chemistry, Dioxoles metabolism, Dose-Response Relationship, Drug, Drug Synergism, Lignans chemistry, Lignans metabolism, MAP Kinase Signaling System physiology, Mitogen-Activated Protein Kinase 3 metabolism, Nerve Growth Factor drug effects, Nerve Growth Factor metabolism, Nerve Growth Factor pharmacology, Neural Pathways drug effects, Neural Pathways growth & development, Neural Pathways metabolism, Neurogenesis drug effects, Neurogenesis physiology, Neurons metabolism, PC12 Cells, Phosphorylation drug effects, Rats, Receptor, trkA agonists, Receptor, trkA antagonists & inhibitors, Receptor, trkA metabolism, Synapses drug effects, Synapses metabolism, Synaptophysin drug effects, Synaptophysin metabolism, Dioxoles pharmacology, Lignans pharmacology, MAP Kinase Signaling System drug effects, Mitogen-Activated Protein Kinase 3 drug effects, Neurons drug effects
- Abstract
Sesamin, a major lignan in sesame seeds, exhibits various health benefits. Here, we investigated effects of sesamin, its stereoisomer episesamin, and their metabolites on neuronal differentiation in rat pheochromocytoma PC12 cells. Among all compounds tested, primary metabolites of sesamin and episesamin, SC-1 and EC-1 {S- and R-epimer of 2-(3,4-methylenedioxyphenyl)-6-(3,4-dihydroxyphenyl)-3,7-dioxabicyclo [3.3.0]octane}, were the most potent to induce neuronal differentiation. SC-1 alone induced neuronal differentiation through extracellular signal-regulated kinase (ERK) 1/2 activation that is essential for nerve growth factor (NGF)-induced neuronal differentiation, as shown by the suppression with MEK1/2 inhibitors, PD98059 and U0126. However, SC-1 did not increase phosphorylation of TrkA, a high-affinity NGF receptor, and a TrkA inhibitor, K252a, did not affect SC-1-induced neuronal differentiation. Furthermore, SC-1 potentiated neuronal differentiation in cells co-treated with NGF, which was associated with enhanced ERK1/2 activation and increased expression of neuronal differentiation markers. Interestingly, when treated with SC-1 and a high dose of NGF, formation of synaptic connections and synaptophysin accumulation at the neurite terminals were markedly enhanced. These results indicate that (1) SC-1 alone induces neuronal differentiation, (2) SC-1 potentiates neuronal differentiation in NGF-treated cells, (3) SC-1 enhances formation of synaptic connections in cells treated with a high dose of NGF, all of which are associated with ERK1/2 activation. It is therefore concluded that SC-1 may promote neuronal differentiation by tapping into the ERK1/2-MAPK (mitogen-activated protein kinase) signaling pathway downstream from the TrkA receptor in PC12 cells.
- Published
- 2009
- Full Text
- View/download PDF
185. Short-term low calorie diet intervention reduces serum advanced glycation end products in healthy overweight or obese adults.
- Author
-
Gugliucci A, Kotani K, Taing J, Matsuoka Y, Sano Y, Yoshimura M, Egawa K, Horikawa C, Kitagawa Y, Kiso Y, Kimura S, and Sakane N
- Subjects
- Adult, Blood Glucose analysis, Blood Pressure, Body Mass Index, Diet Records, Diet, Reducing, Female, Food, Formulated, Humans, Lipids blood, Male, Middle Aged, Obesity blood, Overweight blood, Statistics, Nonparametric, Waist Circumference, Weight Loss, Caloric Restriction, Glycation End Products, Advanced blood, Obesity diet therapy, Overweight diet therapy
- Abstract
Background: Obesity is a metabolic and cardiovascular risk factor. A low calorie diet (LCD) is one of the treatment modalities for weight loss. Serum advanced glycation end products (AGEs) are linked to increased atherogenicity and inflammation in diseases such as diabetes and renal failure. Obesity has an inflammatory component, but interestingly there are no studies on serum AGE levels in obesity or on the effects of LCD as a therapeutic measure on these markers of glycation., Aim: We hypothesized that weight loss by caloric restriction has a beneficial effect on serum AGE levels. We investigated the prospective effects of a sole LCD intervention for weight loss on serum AGEs in a cohort of overweight and non-morbidly obese but otherwise healthy subjects., Methods: A total of 37 Japanese subjects (30 females, 7 males, mean age 48.2 +/- 9.3 years) with a mean BMI of 28.3 +/- 3.2 participated in this study. During the intervention period of 2 months, they were placed on an LCD (Diet's; 5,023 kJ/day) with meal replacement every dinner. The following data were evaluated pre- and post-intervention: AGEs, BMI, waist circumference, blood pressure, serum glucose, cholesterol, triglycerides, HDL- and LDL- cholesterol., Results and Discussion: After the intervention, BMI levels were clearly reduced by 6.3% (p < 0.001), waist circumference by 5.7% (p < 0.002) and triglycerides by 11.9 % (p < 0.002). At baseline, AGEs levels were 63 +/- 11 AU for obese subjects and 63 +/- 14 for control subjects (not significant). After intervention, AGEs were reduced by 7.21% (range 0-35%, p < 0.001). The percent change in AGEs was significantly and positively correlated with that of triglycerides (r = 0.42, p < 0.009), waist circumference (r = 0.40, p < 0.011), and BMI (r = 0.42, p < 0.007). We show for the first time that serum AGEs can be reduced by an LCD intervention on weight loss, a change that correlates with the reduction in triglycerides. This may plausibly be a reflection of a reduction in glycation/lipoxidation due to the caloric restriction and its metabolic consequences, or it may be due to the decreased intake of food containing glycotoxins, or a combination of both., (2009 S. Karger AG, Basel.)
- Published
- 2009
- Full Text
- View/download PDF
186. [New trends in carcinogenic thresholds---International Symposium on "Thresholds for Carcinogens and Mutagens"].
- Author
-
Hori H and Kitagawa Y
- Subjects
- Congresses as Topic, Differential Threshold, Carcinogens toxicity, Mutagens toxicity
- Published
- 2006
187. 2'-benzyloxychalcone derivatives stimulate glucose uptake in 3T3-L1 adipocytes.
- Author
-
Kamei R, Kadokura M, Kitagawa Y, Hazeki O, and Oikawa S
- Subjects
- 3T3 Cells, Adipocytes metabolism, Animals, Cattle, Chalcone analogs & derivatives, Chalcone chemistry, Chalcones, Dose-Response Relationship, Drug, Glucose Transporter Type 4, Insulin pharmacology, Mice, Monosaccharide Transport Proteins metabolism, Structure-Activity Relationship, Adipocytes drug effects, Chalcone pharmacology, Glucose metabolism, Muscle Proteins
- Abstract
By a cell-based glucose uptake screening assay, a chalcone derivative, 3-nitro-2'-benzyloxychalcone (compound 1) was identified. Compound 1 stimulated glucose uptake and potentiated insulin-stimulated glucose uptake in a concentration-dependent manner in 3T3-L1 adipocytes. When cells were treated with various concentrations of insulin in the presence of compound 1, marked enhancement of insulin-stimulated glucose uptake was observed at each concentration, suggesting that the compound might function as an insulin sensitizer. Preliminary study on the structure-activity relationships revealed that two aromatic benzene rings tolerated several substituents, but substitution by acidic or highly polar groups abolished the activity. Among several chalcone derivatives, 4-chloro-2'-benzyloxychalcone (compound 8) showed the highest level of activity. Compound 8-stimulated glucose uptake was almost completely inhibited by wortmannin, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). These results suggest that the action of chalcone derivatives is mediated via a pathway involving PI3K.
- Published
- 2003
- Full Text
- View/download PDF
188. Identification of receptors for pig endogenous retrovirus.
- Author
-
Ericsson TA, Takeuchi Y, Templin C, Quinn G, Farhadian SF, Wood JC, Oldmixon BA, Suling KM, Ishii JK, Kitagawa Y, Miyazawa T, Salomon DR, Weiss RA, and Patience C
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, DNA Primers, Endogenous Retroviruses chemistry, HeLa Cells, Humans, Mice, Molecular Sequence Data, Sequence Homology, Amino Acid, Swine, Endogenous Retroviruses metabolism, Receptors, Virus metabolism
- Abstract
Xenotransplantation of porcine tissues has the potential to treat a wide variety of major health problems including organ failure and diabetes. Balanced against the potential benefits of xenotransplantation, however, is the risk of human infection with a porcine microorganism. In particular, the transmission of porcine endogenous retrovirus (PERV) is a major concern [Chapman, L. E. & Bloom, E. T. (2001) J. Am. Med. Assoc. 285, 2304-2306]. Here we report the identification of two, sequence-related, human proteins that act as receptors for PERV-A, encoded by genes located on chromosomes 8 and 17. We also describe homologs from baboon and porcine cells that also are active as receptors. Conversely, activity could not be demonstrated with a syntenic murine receptor homolog. Sequence analysis indicates that PERV-A receptors [human PERV-A receptor (HuPAR)-1, HuPAR-2, baboon PERV-A receptor 2, and porcine PERV-A receptor] are multiple membrane-spanning proteins similar to receptors for other gammaretroviruses. Expression is widespread in human tissues including peripheral blood mononuclear cells, but their biological functions are unknown. The identification of the PERV-A receptors opens avenues of research necessary for a more complete assessment of the retroviral risks of pig to human xenotransplantation.
- Published
- 2003
- Full Text
- View/download PDF
189. Shikonin stimulates glucose uptake in 3T3-L1 adipocytes via an insulin-independent tyrosine kinase pathway.
- Author
-
Kamei R, Kitagawa Y, Kadokura M, Hattori F, Hazeki O, Ebina Y, Nishihara T, and Oikawa S
- Subjects
- 3T3 Cells, Adipocytes metabolism, Androstadienes pharmacology, Animals, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Biological Transport drug effects, Drugs, Chinese Herbal pharmacology, Enzyme Inhibitors pharmacology, Genistein pharmacology, Glucose Transporter Type 4, Humans, Insulin metabolism, Male, Medicine, Chinese Traditional, Mice, Molecular Structure, Monosaccharide Transport Proteins metabolism, Myocardium cytology, Myocardium metabolism, Phosphorylation, Proto-Oncogene Proteins metabolism, Proto-Oncogene Proteins c-akt, Rats, Rats, Sprague-Dawley, Receptor, Insulin metabolism, Signal Transduction physiology, Vanadates pharmacology, Wortmannin, Adipocytes drug effects, Biological Transport physiology, Glucose metabolism, Muscle Proteins, Naphthoquinones pharmacology, Protein Serine-Threonine Kinases, Protein-Tyrosine Kinases metabolism
- Abstract
Type 2 diabetes is due to defects in both insulin action and secretion. In an attempt to discover small molecules that stimulate glucose uptake, similar to insulin, a cell-based glucose uptake screening assay was performed using 3T3-L1 adipocytes. Shikonin, a substance originally isolated from the root of the Chinese plant that has been used as an ointment for wound healing, was thus identified. Shikonin stimulated glucose uptake and potentiated insulin-stimulated glucose uptake in a concentration-dependent manner in 3T3-L1 adipocytes. Stimulation of glucose uptake was also observed in rat primary adipocytes and cardiomyocytes. Like insulin, shikonin-stimulated glucose uptake was inhibited by genistein, a tyrosine kinase inhibitor, and enhanced by vanadate, a tyrosine phosphatase inhibitor. However, in contrast to insulin, shikonin-stimulated glucose uptake was not strongly inhibited by wortmannin, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). In vitro phosphorylation analyses revealed that shikonin did not induce tyrosine phosphorylation of the insulin receptor, but significantly induced both Thr-308 and Ser-473 phosphorylation of Akt. Our results suggest that in 3T3-L1 adipocytes, shikonin action is not mediated primarily via the insulin receptor/PI3K pathway, but rather via another distinct tyrosine kinase-dependent pathway leading to glucose uptake involving Akt phosphorylation.
- Published
- 2002
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.