論文 - 榊原 陽一
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Yamasaki M., Iwase M., Kawano K., Sakakibara Y., Suiko M., Ikeda M., Nishiyama K.
Journal of Clinical Biochemistry and Nutrition 54 ( 1 ) 18 - 25 2014年1月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Clinical Biochemistry and Nutrition
Our previous study showed α-lipoic and (LA) downregulated cell surface β1-integrin expression of v-H-ras-transformed derivative of rat fibroblast with amelioration of their malignant phenotype. Here, we evaluated the ameliorating effect of LA on the malignant characters in H-ras-transformed bladder cancer cells. H-ras mutated bladder cancer line, T24 cells were incubated with LA to evaluate the inhibitory effect on proliferation, migration, invasion and β1-integrin expression. Fluorescence staining of F-actin and western blotting analyses of the related signaling pathways were also performed. LA inhibited the proliferation of T24 cells. Cell adhesion to collagen IV and fibronectin was strikingly inhibited by LA treatment accompanied by downregulation of cell surface but not whole cell β1-integrin expression. LA clearly inhibited cell migration and invasion of T24 cells, which were mimicked by extra-cellular signal-regulated kinase (ERK) and Akt pathway inhibition. Actually, LA significantly downregulated the phosphorylated ERK and Akt levels. Moreover, LA downregulated phosphorylated focal adhesion kinase level with disappearance of stress fiber formation. Finally, although LA induced the internalization of cell surface β1-integrin, disruption of the raft did not affect the action of LA. Taken together, LA is a promising agent to improve malignant character of bladder cancer cells through regulation of cellular β1-integrin localization. ©2014 JCBN.
DOI： 10.3164/jcbn.13-57
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Nagahama K., Eto N., Sakakibara Y., Matsusita Y., Sugamoto K., Morishita K., Suiko M.
Journal of Functional Foods 6 ( 1 ) 356 - 366 2014年
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Functional Foods
Adult T-cell leukemia/lymphoma (ATLL) is an aggressive disease caused by human T-cell lymphotropic virus type 1 (HTLV-1). As ATLL develops over many years, daily diet may play an important role in its occurrence. In this study, we investigated the growth inhibitory effect of extracts of blueberry leaf fractions on HTLV-1-associated cell lines. The most effective fraction contained highly oligomeric proanthocyanidins (OPA) with a mean degree of polymerization of 3.1. Cell growth inhibition by the OPA fraction was higher in all HTLV-1-associated cell lines than in the MOLT-4 HTLV-1-negative T-cells. It inhibited growth of the HTLV-1-infected T-cell line MT2 and ATLL-derived cell line Su9T01 by inducing apoptosis and G2/M cell cycle arrest. OPA fraction-induced apoptosis of HTLV-1-associated cells required death receptor-mediated caspase-dependent pathways. Treatment-induced G2/M arrest resulted from down-regulation of cyclin B1 and cdc2. The blueberry leaf OPA fraction may be a source of novel compounds for reducing the risk of developing ATLL. © 2013 Elsevier Ltd.
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Yamasaki M., Soda S., Sakakibara Y., Suiko M., Nishiyama K.
Bioscience, Biotechnology and Biochemistry 78 ( 11 ) 1939 - 1942 2014年
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Bioscience, Biotechnology and Biochemistry
© 2014 Japan Society for Bioscience, Biotechnology, and Agrochemistry.Here, we show that cell surface β1-integrin expression, cell adhesion to fibronectin, migration, and invasion were all significantly inhibited by α-lipoic acid. These effects were not observed when cells were treated with dihydrolipoic acid or caprylic acid. These data reveal that the 1,2-dithiolane structure plays an important role in the action of α-lipoic acid.
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Induction of apoptotic cell death in HL-60 cells by jacaranda seed oil derived fatty acids 査読あり
Yamasaki M., Motonaga C., Yokoyama M., Ikezaki A., Kakihara T., Hayasegawa R., Yamasaki K., Sakono M., Sakakibara Y., Suiko M., Nishiyama K.
Journal of Oleo Science 62 ( 11 ) 925 - 932 2013年11月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Oleo Science
Various fatty acids are attracting considerable interest for their anticancer effects. Among them, fatty acids containing conjugated double bonds show one of the most potent cytotoxic effects on cancer cells. Here, we focused on the cancer cell killing activity of jacaranda seed oil. The seed oil of jacaranda harvested from Miyazaki in Japan contained 30.9% cis-8, trans-10, cis-12 octadecatrienoic acid, called jacaric acid (JA). Fatty acid prepared from this oil (JFA) and JA strongly induced cell death in human leukemia HL-60 cells. On the other hand, linoleic acid and trans-10, cis-12 conjugated linoleic acid (<10 μM) did not affect cell proliferation and viability. An increase in the sub-G1 population and internucleosomal fragmentation of DNA was observed in JA- and JFA-treated cells, indicating induction of apoptotic cell death. Finally, the cytotoxic effects of JA and JFA were completely abolished by α-tocopherol. Taken together, these data suggest that jacaranda seed oil has potent apoptotic activity in HL-60 cells through induction of oxidative stress. © 2013 by Japan Oil Chemists' Society.
DOI： 10.5650/jos.62.925
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Kurogi K., Kurogi K., Liu T., Sakakibara Y., Suiko M., Liu M.
Drug Metabolism Reviews 45 ( 4 ) 431 - 440 2013年11月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Drug Metabolism Reviews
In recent years, zebrafish has emerged as a useful animal model for biomedical research. The deciphering of the zebrafish genome has revealed that many of the enzymes involved in the metabolism of endogenous compounds and xenobiotics are conserved between zebrafish and humans. This review summarizes the information currently available concerning the zebrafish cytosolic sulfotransferases (SULTs), a group of phase II enzymes that have been proposed to be involved in the regulation and homeostasis of key endogenous compounds and the detoxification of xenobiotics. To date, 20 zebrafish SULTs that fall into six major SULT gene families have been identified. Of the 20 SULTs 18 have been cloned, expressed, purified and characterized. These zebrafish SULTs were shown to exhibit differential substrate specificities for endogenous compounds such as monoamine transmitters, steroid/thyroid hormones and bile salts, as well as xenobiotics including environmental toxicants and drugs. These findings provide a foundation for using zebrafish as a model for investigating further the physiological, pharmacological, and toxicological involvement of the SULTs. © 2013 Informa Healthcare USA, Inc.
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Yamasaki M., Mine Y., Nishimura M., Fujita S., Sakakibara Y., Suiko M., Morishita K., Nishiyama K.
Cell Biology International 37 ( 7 ) 742 - 747 2013年7月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Cell Biology International
We have shown that genistein inhibits the growth of adult T-cell leukemia (ATL) cells in vitro and in vivo, and this leads to pronounced G2/M arrest. This report shows that genistein induces apoptotic death in ATL cells. Although the pan-caspase inhibitor, Z-VAD-fmk, did not inhibit genistein-induced apoptosis, release of apoptosis-inducing factor (AIF) into the cytosol occurred. Poly-ADP ribose polymerase inhibition also abrogated genistein-induced apoptosis. Genistein decreased nuclear p65 translocation and IkBα phosphorylation, and downregulated the anti-apoptotic proteins, XIAP, cIAP and survivin, NF-kBresponsive gene products. Thus, genistein is a promising agent for ATL that induces caspase-independent apoptosis through inhibition of the NF-kB pathway. © 2013 International Federation for Cell Biology.
DOI： 10.1002/cbin.10104
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Identification and characterization of a novel kaempferol sulfotransferase from Arabidopsis thaliana 査読あり
Hashiguchi T., Hashiguchi T., Sakakibara Y., Sakakibara Y., Hara Y., Shimohira T., Kurogi K., Kurogi K., Akashi R., Akashi R., Liu M., Suiko M., Suiko M.
Biochemical and Biophysical Research Communications 434 ( 4 ) 829 - 835 2013年5月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Biochemical and Biophysical Research Communications
In plants, flavonoids have been shown to be subjected to conjugation modifications such as glycosylation, methylation, and sulfation. Among these modifications, sulfation is known as an important pathway in the regulation of the levels of endogenous compounds such as steroids. Although a large variety of flavonoid sulfates also exist in plants, the detailed biochemical characterization of Arabidopsis thaliana sulfotransferases (AtSULTs) remains to be fully clarified. We report here that uncharacterized AtSULT202E1 (AGI code: At2g03770), a SULT202E subfamily member, shows the sulfating activity toward flavonoids. The general characteristics of the enzyme were studied on the optimum temperature and pH, the effect of divalent cations, and the thermal stability with kaempferol as substrate. A comparative analysis of the sulfation of flavonoids by AtSULT202E1, AtSULT202B1 and AtSULT202A1 revealed that three AtSULTs have differential substrate specificities. Surprisingly, 3-hydroxyflavone was sulfated only by AtSULT202A1 while 7-hydroxyflavone was highly sulfated by AtSULT202E1 and AtSULT202B1. These results indicate that flavonols might be sulfated in a position specific manner. In conclusion, our studies indicate that a novel AtSULT202E1 has the sulfating activity toward flavonoids together with AtSULT202B1 and AtSULT202A1. The existence of three flavonoid sulfotransferases in A. thaliana suggests that sulfation of flavonoids have an important role in regulation of their functions. © 2013 Elsevier Inc.
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Teramoto T., Fujikawa Y., Kawaguchi Y., Kurogi K., Soejima M., Adachi R., Nakanishi Y., Mishiro-Sato E., Liu M., Sakakibara Y., Suiko M., Kimura M., Kakuta Y.
Nature Communications 4 2013年4月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Nature Communications
Post-translational protein modification by tyrosine sulfation has an important role in extracellular protein-protein interactions. The protein tyrosine sulfation reaction is catalysed by the Golgi enzyme called the tyrosylprotein sulfotransferase. To date, no crystal structure is available for tyrosylprotein sulfotransferase. Detailed mechanism of protein tyrosine sulfation reaction has thus remained unclear. Here we present the first crystal structure of the human tyrosylprotein sulfotransferase isoform 2 complexed with a substrate peptide (C4P5Y3) derived from complement C4 and 3′- phosphoadenosine-5′-phosphate at 1.9 Å resolution. Structural and complementary mutational analyses revealed the molecular basis for catalysis being an S N 2-like in-line displacement mechanism. Tyrosylprotein sulfotransferase isoform 2 appeared to recognize the C4 peptide in a deep cleft by using a short parallel β-sheet type interaction, and the bound C4P5Y3 forms an L-shaped structure. Surprisingly, the mode of substrate peptide recognition observed in the tyrosylprotein sulfotransferase isoform 2 structure resembles that observed for the receptor type tyrosine kinases. © 2013 Macmillan Publishers Limited. All rights reserved.
DOI： 10.1038/ncomms2593
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Ethanol sulfation by the human cytosolic sulfotransferases: a systematic analysis. 査読あり
Kurogi K, Davidson G, Mohammed YI, Williams FE, Liu MY, Sakakibara Y, Suiko M, Liu MC.
Biol Pharm Bull. 35 ( 12 ) 2180 - 2185 2012年12月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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Yamasaki M., Nagatomo T., Matsuyama T., Ikeho Y., Kato E., Nishiyama K., Sakakibara Y., Suiko M., Nishiyama K.
Journal of Oleo Science 61 ( 9 ) 491 - 496 2012年11月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Oleo Science
The anti-cancer effects of various fatty acids are drawing a lot of attention. To determine whether different fatty acids affect the hypoxic response of liver cancer cells, we examined the effects of various fatty acids on the stabilization of the hypoxia-inducible factor (HIF)-1α protein in the HepG2 human hepatocellular carcinoma (HCC) cell line under condition containing 1% O 2. Of the fatty acids examined, only 9cis, 11trans (c9, t11)-conjugated linoleic acid (CLA) and 10trans, 12cis (t10, c12)-CLA inhibited hypoxia-induced HIF-1α stabilization. In addition, HIF-1α prolyl hydroxylase or proteasome inhibition abrogated the effects of c9, t11- and t10, c12-CLA. Moreover, c9, t11- and t10, c12-CLA significantly inhibited cell proliferation and induced apoptotic cell death under hypoxia. This is the first study showing that c9, t11- and t10, c12-CLA inhibit the hypoxic response in HCC cells. ©2012 by Japan Oil Chemists' Society.
DOI： 10.5650/jos.61.491
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Kurogi K., Alazizi A., Liu M., Sakakibara Y., Suiko M., Sugahara T., Liu M.
Biochemical Pharmacology 84 ( 9 ) 1186 - 1195 2012年11月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Biochemical Pharmacology
Catecholic drugs had been reported to be metabolized through conjugation reactions, particularly methylation and sulfation. Whether and how these two Phase II conjugation reactions may occur in a concerted manner, however, remained unclear. The current study was designed to investigate the methylation and/or sulfation of five catecholic drugs. Analysis of the spent media of HepG2 cells metabolically labeled with [35S]sulfate in the presence of individual catecholic drugs revealed the presence of two [35S] sulfated metabolites for dopamine, epinephrine, isoproterenol, and isoetharine, but only one [35S]sulfated metabolite for apomorphine. Further analyses using tropolone, a catechol O-methyltransferase (COMT) inhibitor, indicated that one of the two [35S]sulfated metabolites of dopamine, epinephrine, isoproterenol, and isoetharine was a doubly conjugated (methylated and sulfated) product, since its level decreased proportionately with increasing concentrations of tropolone added to the labeling media. Moreover, while the inhibition of methylation resulted in a decrease of the total amount of [ 35S]sulfated metabolites, sulfation appeared to be capable of compensating the suppressed methylation in the metabolism of these four catecholic drugs. A two-stage enzymatic assay showed the sequential methylation and sulfation of dopamine, epinephrine, isoproterenol, and isoetharine mediated by, respectively, the COMT and the cytosolic sulfotransferase SULT1A3. Collectively, the results from the present study implied the concerted actions of the COMT and SULT1A3 in the metabolism of catecholic drugs. © 2012 Elsevier Inc. All rights reserved.
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Sulfation of ractopamine and salbutamol by the human cytosolic sulfotransferases. 査読あり
Ko K, Kurogi K, Davidson G, Liu MY, Sakakibara Y, Suiko M, Liu MC.
J Biochem. 152 ( 3 ) 275 - 283 2012年9月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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Uchida A., Sassa H., Takenaka S., Takenaka S., Sakakibara Y., Suiko M., Kunitake H.
Plant OMICS 5 ( 4 ) 320 - 325 2012年7月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Plant OMICS
The differences between stylar protein of the Japanese pear (Pyrus pyrifolia (Burm.f.)) cultivars 'Kosui' (S4S5) and 'Kikusui' (S2S4) were compared by two-dimensional difference gel electrophoresis (2-D DIGE), and were labelled and visualized with different fluorescent dyes (IC3-OSu, IC5-OSu) on a single 2-D gel. The individual different expressed proteins spots were subjected to identification. The proteins were analyzed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF/MS) to identify proteins related to gametophytic self-incompatibility (GSI). S4-RNase and thaumatin-like protein 1 were successfully detected as expected in the pistils of 'Kosui' and 'Kikusui'. S5-RNase was also detected in the pistils of 'Kosui'. However, we could not detect S2-RNase in 'Kikusui' in this study, possibly because the level of expression of S2-RNase might be minuscule, or the estimated isoelectric point (pI) of S2-RNase (pI:9.26) was more basic than S4-RNase (pI: 9.17) and S5-RNase (pI: 9.01). These results indicate that proteomic studies are effective tools for detection of the expected proteins and might be helpful for finding the unknown key proteins related to the mechanism of self-incompatibility (SI) in many other SI plants.
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Yamasaki M., Iwase M., Kawano K., Sakakibara Y., Suiko M., Nishiyama K.
Bioscience, Biotechnology and Biochemistry 76 ( 6 ) 1177 - 1181 2012年6月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Bioscience, Biotechnology and Biochemistry
We determined the effects of apocynin, a representative inhibitor of NADPH oxidase, on the proliferative and adhesive properties of 3Y1 rat fibroblasts and the 3Y1 v-H-ras-transformed derivative, HR-3Y1-2. Apocynin inhibited the proliferation of HR-3Y1-2 but not 3Y1 cells at 10μM and 100μM. Apocynin also decreased the intracellular reactive oxygen species (ROS) level in HR-3Y1-2 but not 3Y1 cells. We also evaluated the effects of apocynin on cell adhesion to fibronectin and found decreased adhesion of HR-3Y1-2 cells to fibronectincoated plates. Our results indicate that apocynin selectively down-regulated β1-integrin cell surface expression on the HR-3Y1-2 cells. It also inhibited the migration and invasion of these cells. These data suggest that reducing the production of NADPH oxidasemediated ROS could be an effective means for ameliorating the abnormal growth, adhesion and motility of v-H-ras-transformed cells.
DOI： 10.1271/bbb.120061
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Apocynin Selectively Inhibits Proliferation, Adhesion to Fibronectin of v-H-ras-transformed 3Y1 Cells. 査読あり
4) Yamasaki, M., Iwase, M., Kawano, K., Sakakibara, Y., Suiko, M., and K. Nishiyama.
Biosci. Biotechnol. Biochem. 76 1177 - 1181 2012年6月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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Sulfation of Buprenorphine, Pentazocine, and Naloxone by Human Cytosolic Sulfotransferases 査読あり
Kurogi, K., Chen, M., Lee, Y., Shi, B., Yang, T., Liu, M.-Y., Sakakibara, Y., Suiko, M., Liu, M.-C.
Drug Metab. Lett. 6 109 - 115 2012年6月
記述言語：英語 掲載種別：研究論文（学術雑誌）
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Identification and characterization of zebrafish SULT1 ST9, SULT3 ST4, and SULT3 ST5 査読あり
Mohammed Y., Kurogi K., Shaban A., Xu Z., Liu M., Williams F., Sakakibara Y., Suiko M., Bhuiyan S., Liu M.
Aquatic Toxicology 112-113 11 - 18 2012年5月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Aquatic Toxicology
By searching the GenBank database, we identified sequences encoding three new zebrafish cytosolic sulfotransferases (SULTs). These three new zebrafish SULTs, designated SULT1 ST9, SULT3 ST4, and SULT3 ST5, were cloned, expressed, purified, and characterized. SULT1 ST9 appeared to be mostly involved in the metabolism and detoxification of xenobiotics such as β-naphthol, β-naphthylamine, caffeic acid and gallic acid. SULT3 ST4 showed strong activity toward endogenous compounds such as dehydroepiandrosterone (DHEA), pregnenolone, and 17β-estradiol. SULT3 ST5 showed weaker, but significant, activities toward endogenous compounds such as DHEA and corticosterone, as well as xenobiotics including mestranol, β-naphthylamine, β-naphthol, and butylated hydroxyl anisole (BHA). pH-dependency and kinetic constants of these three enzymes were determined with DHEA, β-naphthol, and 17β-estradiol as substrates. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to examine the expression of these three new zebrafish SULTs at different developmental stages during embryogenesis, through larval development, and on to maturity. © 2012 Elsevier B.V..
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Yamasaki M., Iwase M., Kawano K., Sakakibara Y., Suiko M., Nishiyama K.
Journal of Clinical Biochemistry and Nutrition 50 ( 3 ) 234 - 240 2012年5月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of Clinical Biochemistry and Nutrition
Here, we focused on the effects of racemic α-lipoic acid on pro-liferation and adhesion properties of 3Y1 rat fibroblasts and the v-H-ras-transformed derivative, HR-3Y1-2 cells. Racemic α-lipoic acid inhibited proliferation of HR-3Y1-2 but not 3Y1 cells at 0.3 and 1.0 mM. R-(+)-α-lipoic acid also inhibited proliferation of HR-3Y1-2 cells equivalent to that of racemic α-lipoic acid. In addition, racemic α-lipoic acid decreased intracellular reactive oxygen species levels in HR-3Y1 cells but not 3Y1 cells. Next, we evaluated the effects of racemic α-lipoic acid on cell adhesion to fibronectin. The results indicated that racemic α-lipoic acid decreased adhesive ability of HR-3Y1-2 cells to fibronectin-coated plates. As blocking antibody experiment revealed that β1-integrin plays a key role in cell adhesion in this experimental system, the effects of racemic α-lipoic acid on the expression of β1-integrin were examined. The results indicated that racemic α-lipoic acid selectively downregulated the expression of cell surface β1-integrin expression in HR-3Y1-2 cells. Intriguingly, exogenous hydrogen peroxide upregulated cell surface β1-integrin expression in 3Y1 cells. Taken together, these data suggest that reduction of intracellular reactive oxygen species levels by α-lipoic acid could be an effective means of ameliorating abnormal growth and adhesive properties in v-H-ras transformed cells. ©2012 JCBN.
DOI： 10.3164/jcbn.11-67
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Uchida A., Takenaka S., Takenaka S., Sakakibara Y., Kurogi S., Honsho C., Sassa H., Suiko M., Kunitake H.
Journal of the Japanese Society for Horticultural Science 81 ( 2 ) 150 - 158 2012年4月
記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Journal of the Japanese Society for Horticultural Science
In Citrus, self-incompatibility (SI) regulation is gametophytic, and this phenomenon is an economically critical problem for some Citrus cultivars without high parthenocarpic ability. Few molecular biological studies of SI in Citrus have been performed, and the molecular mechanism of SI has not been clarified. To investigate the effect of different stages of style development on pollen tube behavior, flower buds of self-incompatible 'Hyuganatsu' (Citrus tamurana hort. ex Tanaka) were histologically assayed. When the flower buds were observed 168 hours after pollination, pollen tubes in the self-pollinated flower buds 1 and 3 days before anthesis (DBA) were arrested in the upper part of the styles, while those in flower buds self-pollinated 5 DBA reached the base of the styles. These results revealed that SI in 'Hyuganatsu' has not yet occurred in the flower buds 5 DBA, but generated in the flower buds 3 DBA. To search SI-related pistil proteins in Citrus, we profiled a number of protein expressions in 'Hyuganatsu' styles of 1, 3, and 5 DBA by two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. One-hundred thirty-eight protein spots were significantly different in abundance among the three stages, and 17 up-regulated and 26 down-regulated protein spots could be identified. Among the 17 up-regulated proteins, nine up-regulated proteins exhibited the expression pattern of 1 DBA ≥ 3 DBA > 5 DBA, a pattern which reflected the transmission from SC to SI, evaluated by pollen tube growth. BLASTP homology search against the peptide sequences of these proteins was carried out and predicted the proteins related to the maintenance of cell shape, the signaling of pollen tube growth, the flavonol biosynthesis, the responses to various stresses, photosynthesis, and the methionine metabolic process. Among the nine proteins, some may be the SI-related pistil proteins; however, it was not possible to determine the SI-related key protein of the style in Citrus. © 2012.
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Conjugated linoleic acids inhibit hypoxia inducible factor-1alpha stabilization under hypoxic condition in human hepatocellular carcinoma cells. 査読あり
Yamasaki, M., Nagatomo, T., Matsuyama, T., Ikeho, Y., Kato, E., Nishiyama, K., Sakakibara, Y., Suiko, M., Nishiyama, N.
J. Oleo Sci. 61 ( 9 ) 491 - 496 2012年4月
記述言語：英語 掲載種別：研究論文（学術雑誌）