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Nanae SHIMONO, Yuuki NISHIMURA, Hiroshi KAMIGUCHI, Yoshihisa NISHIKAWA
2011 Volume 75 Issue 8 Pages
1451-1455
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
Advance online publication: August 07, 2011
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We cloned a novel human mannosyltransferase-like gene, designated
Hmat-Xa, as a gene homologous to the
Drosophila GC15914 gene encoding the 9QVXN0 protein: see “Project Report for FY2002 on the ‘Construction of Libraries of Human Genes Participating in Glycosylation’ project” 43–45 (2003), New Energy and Industrial Technology Development Organization (NEDO), NEDO and Research Association for Biotechnology, Tokyo, Japan (in Japanese). After that, the GTDC1 gene, as reported by Zhao
et al.,
DNA Cell Biol.,
23, 183–187 (2004), was found to be the same as the
Hmat-Xa gene. Domain EXFGI/L/VX
2L/VE in the Hmat-Xa protein, also present in both human mannosyltransferase II/III and mannosyltransferase IV/V, which are involved in the synthesis of lipid-linked oligosaccharides, and some bacterial mannosyltransferases. A real-time PCR study of
Hmat-Xa mRNA expression in human normal and tumor multiple tissue cDNA identified its tissue-specific expression and its remarkable expression in colon adenocarcinoma as compared to the normal counterpart. Thus the elevated expression of
Hmat-Xa might serve as a candidate marker for colon adenocarcinoma.
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Dipali Rani GUPTA, Swapan Kumar PAUL, Yasuo OOWATARI, Yasuhiro MATSUO, ...
2011 Volume 75 Issue 8 Pages
1456-1465
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Nine
sam mutants that undergo sexual differentiation without requiring starvation in
Schizosaccharomyces pombe were previously isolated. In this study, we identified a nonsense mutation on the
pka1 locus in the
sam6 mutant.
pka1 encodes a catalytic subunit of protein kinase A (PKA). Replacement and overexpression of
pka1 suppressed the KCl sensitivity and hyper-mating phenotype of
sam6, confirming that
sam6 is an allele of
pka1. To characterize further the regulation of Pka1, we tested the physical interaction between Pka1 and Cgs1 (a regulatory subunit of PKA). Pka1 and Cgs1 physically interacted under glucose-limited conditions but not under glucose-rich conditions. In addition, the formation of a Pka1-Cgs1 complex was detected under glucose-limited conditions by Blue Native PAGE. Furthermore, the Pka1 protein was found to be phosphorylated under glucose-starved conditions, and at the same time its localization shifted from the nucleus towards the cytoplasm (mainly the vacuoles), suggesting a strong relationship among phosphorylation, complex formation, and the cytoplasmic distribution of Pka1.
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Takehiko YOKOYAMA, Masafumi AMANO, Masae SEKINE, Hiroshi HOMMA, Masaha ...
2011 Volume 75 Issue 8 Pages
1481-1484
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Immunohistochemical localization (cellular localization) of endogenous
D-aspartate in the marine brown alga
Sargassum fusiforme was investigated by the use of a specific polyclonal antibody raised against
D-aspartate.
D-Aspartate immunoreactivity was evident in the medullary layer in the blade of the alga, and weak staining was found in the cortical layer, whereas epidermal cells were found to lack
D-aspartate. Within the cells of the layers, immunoreactivity was confirmed only in the cytosol and not in the cell wall, chloroplast, or vacuole. These results suggest that
D-aspartate is present in
S. fusiforme cells, and excludes the possibility that it is derived from attached or symbiotic organisms such as marine bacteria. This is the first report describing the localization of free
D-aspartate in plant cells.
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Hiroyuki NAGAI, Tsuyoshi GOTO, Nobuyuki TAKAHASHI, Tatsuya KUSUDOH, Yo ...
2011 Volume 75 Issue 8 Pages
1485-1489
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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A useful method employing liquid chromatography mass spectrometry (LC/MS) and a stable isotope was developed for simultaneous examination of major metabolism in adipocytes,
de novo fatty acid synthesis, glycerol output, and glucose uptake with high sensitivity. The addition of thiazolidinediones, potent agonists of peroxisome proliferator-activated receptors-γ, for 10 d increased glucose uptake in a dose-dependent manner. Fatty acid (FA) synthesis increased at low concentrations of thiazolidinediones (TZDs) and decreased at high concentrations. It is important to assess adipocytes from various examples of metabolism, because each example of adipocyte metabolism is directly related to obesity or metabolic syndrome in various ways. The technique makes metabolic examination easier than conventional methods by means of radioisotopes and makes it possible to identify metabolites and to apply them in biomarker screening.
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Takayasu KAWASAKI, Kenji ONODERA, Shunsuke KAMIJO
2011 Volume 75 Issue 8 Pages
1496-1501
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Supplementary material
Since the soluble oligomers of 42-residue amyloid β (Aβ42) might be neurotoxins at an early stage of Alzheimer’s disease (AD), inhibition of soluble Aβ42 oligomerization should be effective in the treatment of AD. We have found by phage display that a 7-residue peptide, SRPGLRR, exhibited inhibitory activity against soluble 37/48 kDa oligomers of Aβ42. In the present study, we newly prepared 3- and 4-residue random peptides libraries and performed pannings of them against soluble Aβ42 to search for important factors in the inhibition of Aβ42 oligomerization. After the fifth round, arginine-containing peptides were enriched in both libraries. SDS–PAGE and size-exclusion chromatography indicated that the inhibitory activities of 4-residue peptides against the soluble 37/48 kDa oligomers of Aβ42 were higher than those of the 3-residue peptides, and RFRK exhibited strong inhibitory activity as well as SRPGLRR. These short peptides should be useful for the suppression of soluble Aβ42 oligomer formation.
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Eriko MATSUO, Toshihiro NAGAMINE, Shogo MATSUMOTO, Kazuhide TSUNEIZUMI
2011 Volume 75 Issue 8 Pages
1511-1515
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Nucleostemin (NS), a nucleolar guanosine triphosphate (GTP)-binding protein, plays significant roles in cell cycle progression and ribosomal biogenesis.
Drosophila Nucleostemin 2 (NS2), a member of the
Drosophila NS family, regulates early eye development and is essential to cell survival
in vivo, but the underlying mechanisms have yet to be clarified. Biochemical analysis using the recombinant NS2 protein indicated that NS2 has GTPase activity. Immunohistochemistry revealed that NS2 changes in subcellular locus from the nucleolus to the nucleoplasm during larval development, and that a mutation in the ATP/GTP-binding site motif A (p-loop) prevents nuclear localization of NS2 and results in cytoplasmic distribution. Furthermore, downregulation of NS2 altered the rRNA proportions between the nucleus and the cytoplasm. These results suggest that NS2 at least requires GTP to import into the nucleoplasm.
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Yinxia LI, Manabu ISHIDA, Hiroyuki ASHIDA, Takahiro ISHIKAWA, Hitoshi ...
2011 Volume 75 Issue 8 Pages
1524-1532
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Supplementary material
We report the molecular characterization and physiological function of a novel
L-aspartate dehydrogenase (AspDH). The purified enzyme was a 28-kDa dimeric protein, exhibiting high catalytic activity for
L-aspartate (
L-Asp) oxidation using NAD and/or NADP as cofactors. Quantitative real-time PCR analysis indicated that the genes involved in the AspDH gene cluster, poly-3-hydroxyalkanoate (PHA) biosynthesis, and the TCA cycle were substantially induced by
L-Asp in wild-type cells. In contrast, expression of the aspartase and aspartate aminotransferase genes was substantially induced in the AspDH gene knockout mutant (ΔB3576) but not in the wild type. GC-MS analyses revealed that the wild-type strain synthesized poly-3-hydroxybutyrate from fructose or
L-Asp, whereas the ΔB3576 mutant did not synthesize PHA from
L-Asp. AspDH gene cluster products might be involved in the biosynthesis of the PHA precursor, revealing that AspDH was a non-NadB type enzyme, and thus entirely different from the previously reported NadB type enzymes working in NAD biosynthesis.
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Saori YAMAWAKI, Takafumi YAMASHINO, Hanayo NAKANISHI, Takeshi MIZUNO
2011 Volume 75 Issue 8 Pages
1533-1539
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Supplementary material
The developmental programs of
Physcomitrella patens, a basal lineage of land plants, are regulated by phytohormones and light-signaling responses. In this study, our attention was focused on the HY5-family of transcription factors, which are known to play important roles immediately downstream of photoreceptors during the early photomorphogenesis of
Arabidopsis thaliana. We retrieved two HY5-homologs, named
PpHY5a and
PpHY5b, from the whole genome sequence database of
P. patens.
Arabidopsis transgenic plants overproducing the basic leucine zipper (bZIP) domain of
PpHY5a exhibited a phenotype of short hypocotyls, suggesting a functional relationship between
PpHY5 and
Arabidopsis HY5. A loss-of-function Δ
hy5a Δ
hy5b double mutant was defective in the vigorous protrusion of caulonema cells from the protonema networks of
P. patens under light and dark conditions. These results suggest that the function of HY5-homologs in
P. patens is evolutionarily conserved, and is implicated in a process of caulonema development.
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Shao-Xiang WANG, Huai-Qiang JU, Kai-Sheng LIU, Jia-Xuan ZHANG, Xiao WA ...
2011 Volume 75 Issue 8 Pages
1540-1545
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
Advance online publication: August 07, 2011
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SNX-2112 is a heat shock protein 90 (Hsp90) inhibitor with anticancer properties currently in clinical trials. This study investigated the effects of SNX-2112 on inhibition of cell growth, the cell cycle, and apoptosis in MCF-7 human breast cancer cells, in addition to the various molecular mechanisms. The results of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometric analysis suggest that SNX-2112 inhibits cell growth in a time- and dose-dependent manner more potently than 17-(allylamino)-17-demethoxygeldanmycin (17-AAG), a traditional Hsp90 inhibitor, probably as a result of cell-cycle arrest at the G2/M phase and the induction of apoptosis. Downregulation of Bcl-2 and Bcl-xL, upregulation of Bax, cleavage of caspase-9 and poly (ADP-ribose) polymerase (PARP), and degradation of the breast cancer-related Hsp90 client proteins human epidermal growth factor receptor-2 (HER2), Akt, Raf-1, and nuclear factor kappa-B kinase (IKK) were observed in SNX-2112 treated cells by Western blot assay. These findings suggest that the molecular mechanisms of cell-growth inhibition by SNX-2112 involve activation of the mitochondrial apoptotic pathway and the degradation of breast cancer-related proteins.
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Mitsuaki SANADA, Kouichi KURODA, Mitsuyoshi UEDA
2011 Volume 75 Issue 8 Pages
1546-1553
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
Advance online publication: August 07, 2011
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Supplementary material
GTS1 of
Saccharomyces cerevisiae is a pleiotropic gene. Its induction leads to a variety of biological phenomena represented by cell aggregation. The C-terminal polyglutamine sequence in Gts1p is indispensable for its pleiotropy and nuclear localization. This sequence is often observed in polyglutamine diseases, such as Huntington disease, and is believed to induce protein aggregation, leading to cell death. In this study, protein aggregates were formed in a polyglutamine-dependent manner in cells inducing
GTS1, and heat-shock protein family, translation elongation factor, and mitochondrial proteins were trapped in Gts1p-mediated protein aggregates. Moreover, the polyglutamine sequence of Gts1p was indispensable to the induction of reactive oxygen species (ROS) production and apoptosis. Deletion of the genes encoding Por1p and Yhb1p altered the profiles of ROS production and apoptosis caused by
GTS1 induction, suggesting that the trapping of these proteins in Gts1p-mediated protein aggregates inhibits the intrinsic functions of these proteins.
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Momoko KOBAYASHI, Hironori HONDOH, Haruhide MORI, Wataru SABURI, Masay ...
2011 Volume 75 Issue 8 Pages
1557-1563
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Dextran glucosidase from
Streptococcus mutans (SmDG), which belongs to glycoside hydrolase family 13 (GH13), hydrolyzes the non-reducing terminal glucosidic linkage of isomaltooligosaccharides and dextran. Thermal deactivation of SmDG did not follow the single exponential decay but rather the two-step irreversible deactivation model, which involves an active intermediate having 39% specific activity. The presence of a low concentration of CaCl
2 increased the thermostability of SmDG, mainly due to a marked reduction in the rate constant of deactivation of the intermediate. The addition of MgCl
2 also enhanced thermostability, while KCl and NaCl were not effective. Therefore, divalent cations, particularly Ca
2+, were considered to stabilize SmDG. On the other hand, CaCl
2 had no significant effect on catalytic reaction. The enhanced stability by Ca
2+ was probably related to calcium binding in the β→α loop 1 of the (β⁄α)
8 barrel of SmDG. Because similar structures and sequences are widespread in GH13, these GH13 enzymes might have been stabilized by calcium ions.
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Tomoko MIYAKE, Kiyoshi YASUKAWA, Kuniyo INOUYE
2011 Volume 75 Issue 8 Pages
1564-1569
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Green tea catechins inhibit human matrix metalloproteinase 7 (MMP-7) activity non-competitively, and the galloyl group is essential for potent inhibition (Oneda
et al.,
J. Biochem.,
133, 571–576 (2003)). In this study, we analyzed the mechanism of this inhibition. In the hydrolysis of (7-methoxycoumarin-4-yl)acetyl-
L-Pro-
L-Leu-Gly-
L-Leu-[
N3-(2,4-dinitrophenyl)-
L-2,3-diaminopropionyl]-
L-Ala-
L-Arg-NH
2, the inhibitory effects of (−)-epigallocatechin-3-gallate (EGCG), (−)-gallocatechin-3-gallate (GCG), (−)-epicatechin-3-gallate (ECG), and (−)-catechin-3-gallate (CG) increased with increasing pH levels from 7.0 to 8.5. The inhibitory effects of EGCG and GCG were more potent than those of ECG and CG, and increased with increasing CaCl
2 concentrations from 10 to 50 m
M. The fluorescence of EGCG and GCG decreased with increasing CaCl
2 concentrations and with the addition of MMP-7, while those of ECG and CG did not. Our results suggest that these differences result from that in the B ring, EGCG and GCG have phenol hydroxyl groups at the 3′, 4′, and 5′ positions, while ECG and CG have them at the 3′ and 4′ positions.
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Chiyomi NISHIDA, Takeo TOMITA, Makoto NISHIYAMA, Ryuyo SUZUKI, Mutsuko ...
2011 Volume 75 Issue 8 Pages
1570-1575
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
Advance online publication: August 07, 2011
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Supplementary material
A/B-Transferase is a glycosyltransferase that transfers a sugar substrate onto H-antigen, which is responsible for the synthesis of glycoprotein- and glycolipid-conjugates termed A/B-antigens. One polymorphism that causes the Pro234Ser substitution in B-transferase was recently found in a genotyping study, and might be
cis-AB. In the present study, we analyzed the phenotypes arising from the enzymatic specificity of B-transferase with the Pro234Ser mutation. To evaluate the effect of the P234S mutation on enzymatic specificity, we generated an expression plasmid for B-transferase with Pro234Ser as well as A-transferase with Leu266Met, which is frequently found in
cis-ABs. Transfection of B-transferase/P234S or A-transferase/L266M cDNA into HeLa cells, an O-blood group cell line, resulted in an AB-phenotype by absorption-elution testing and immunostaining, whereas A- and B-transferase-expressing HeLa cells exhibited only their own activity. Molecular simulation indicated that the P234S mutation causes a conformational change in the substrate pocket making it suitable for
N-acetylgalactosamine.
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Lingzhu MENG, Ming LI, Seung Hwan YANG, Tae-Jong KIM, Joo-Won SUH
2011 Volume 75 Issue 8 Pages
1576-1581
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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The addition of extracellular ATP (exATP) to four
Streptomyces strains had similar effects: low exATP levels stimulated antibiotic production and high levels reduced it. Compared with antibiotic production, the concentrations of intracellular ATP (inATP) in the tested strains were opposite, which suggests a role of inATP in regulating secondary metabolite production. Under inactivation of the polyphosphate kinase gene (
ppk) in
Streptomyces lividans, we observed the same results: when the inATP level in the mutant strain was lower than in the parent strain, more antibiotic was produced. Combining all the results, a strong inverse relationship between [inATP] and the secondary metabolite production is suggested by this study.
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Tomoya SAKAMOTO, Yuko YAMAGUCHI, Tsuyoshi GOTO, Nobuyuki TAKAHASHI, Te ...
2011 Volume 75 Issue 8 Pages
1582-1587
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Supplementary material
Monitoring of inflammation in adipose tissues, which causes insulin resistance, is valuable in evaluating insulin resistance. We developed an
in vitro analysis system using a fluorescence protein (FP) as a reporter gene driven by pro-inflammatory cytokine promoters such as monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNFα). In the reporter-transfected RAW264 cells, the protein expression levels of green fluorescence protein (GFP) were increased by inflammatory stimulations such as lipopolysaccharide (LPS), conditioned medium prepared using hypertrophied 3T3-L1 adipocytes, and a co-culture system. The changes in fluorescence intensity were equivalent to those of the mRNA and protein expression levels for each cytokine. Moreover, the effects of 15-deoxy-12,14Δ-prostaglandine J
2, a natural anti-inflammatory compound, were detectable in this system. These data indicate that the FP system developed here is an analysis system of low cost with simple procedures for evaluating inflammation, suggesting usability in the large-scale screening of anti-inflammatory compounds.
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Takumi CHINEN, Yu OTA, Yoko NAGUMO, Hiroshi MASUMOTO, Takeo USUI
2011 Volume 75 Issue 8 Pages
1588-1593
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Supplementary material
Budding yeast is often used in chemical genetics for screening, target identification, and compound verification, but its high-level drug resistance has made the analysis of compounds difficult. Here we report the construction of 12geneΔ0HSR, a strain that lacks eight efflux pumps located on the plasma membrane and four transcription factors involved in expression of efflux pumps, and contains the
RME1(ins-308A) mutation. This strain retained sufficient transformation, mating, and sporulation efficiency for genetic analysis in addition to hypersensitivity against several compounds. 12geneΔ0HSR is a useful tool for chemical biology, not only in chemical screening but in target identification and verification of bioactive compounds.
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Kayoko KAWAKAMI, Saiko AKETA, Hiroki SAKAI, Yusuke WATANABE, Hiroshi N ...
2011 Volume 75 Issue 8 Pages
1435-1439
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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The antihypertensive and vasorelaxant effects of water-soluble proanthocyanidins, extracted in persimmon leaf tea, were investigated in spontaneously hypertensive rats, rat aortas, and human umbilical vein endothelial cells. Oral administration of proanthocyanidins significantly decreased the systolic blood pressure of the rats after 4 h, as compared with distilled water controls. A vasorelaxant effect on rat aortas was induced by proanthocyanidins, and it was abolished by removal of the endothelium and inhibition of endothelial nitric oxide synthase and soluble guanylyl cyclase activity. The phosphorylation levels of endothelial nitric oxide synthase (Ser-1177) and the upstream kinase Akt (Ser-473) in umbilical cells also increased in a time-dependent manner after the addition of a proanthocyanidin-rich fraction. These results suggest that the antihypertensive effect of proanthocyanidins in persimmon leaf tea is due to vasorelaxation
via an endothelium-dependent nitric oxide/cGMP pathway, and that proanthocyanidins might be useful in dietary lowering of blood pressure.
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Ik-Hyun CHO, Min Jung LEE, Jong-Hyun KIM, Na Young HAN, Kyu Won SHIN, ...
2011 Volume 75 Issue 8 Pages
1440-1445
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Supplementary material
Fritillaria ussuriensis (FU, derived from the bulbs of various species of the genus
Fritillaria, including
Fritillaria thunbergii Miq.) is used in herbal medicine to treat conditions such as eczema, skin burns, and frostbite. In this study, we investigated the mechanism of the anti-allergy effect of FU. FU extract (80 mg/kg), orally administered to Sprague-Dawley (SD) rats, significantly inhibited the passive cutaneous anaphylaxis (PCA) reaction. It inhibited the compound 48/80-induced release of histamine from rat peritoneal mast cells in a concentration-dependent manner. Significant inhibitory effects of the FU extract on IL-6, IL-8, and TNF-α (1, 10, and 100 μg/mL) were observed in HMC-1 cells. Treatment with FU attenuated PMA plus A23187-induced phosphorylation of all three MAPKs, especially at concentrations of 10 and 100 μg/mL. Further, it (80 mg/kg) led to significant inhibition of mast-cell accumulation in ear tissue at the chronic phase. These results indicate that it inhibits allergic reactions.
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Jie XU, Yu-Ming WANG, Ting-Yu FENG, Bei ZHANG, Tatsuya SUGAWARA, Chang ...
2011 Volume 75 Issue 8 Pages
1466-1471
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Cerebrosides are a kind of important bioactive substance in sea cucumber. A novel cerebroside, AMC-2, was purified from the less-polar lipid fraction of the sea cucumber
Acaudina molpadioides by repeated column chromatography. The major structure of AMC-2 was analyzed by gas chromatography-mass spectra. The amide-linked fatty acid unit was confirmed to be four saturated and monounsaturated α-hydroxy fatty acids, the long-chain base was dihydroxy sphingoid base with one double bond, and the glycosyl group was glucose. We also investigated the anti-fatty liver activity of AMC-2 in rats with fatty liver induced by orotic acid. AMC-2 significantly reduced hepatic triglyceride (TG) and total cholesterol (TC) levels at a diet supplement of 0.03% and 0.006%. The indexes of stearoyl-CoA desaturase (SCD) activity and mRNA expression were significantly decreased by AMC-2. This indicates that AMC-2 ameliorated nonalcoholic fatty liver disease (NAFLD) through suppression of SCD activity and impaired the biosynthesis of monounsaturated fatty acids in the livers of the rats.
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Hye Eun MOON, Md. Nurul ISLAM, Bo Ra AHN, Sabiha Sultana CHOWDHURY, He ...
2011 Volume 75 Issue 8 Pages
1472-1480
Published: August 23, 2011
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The present work investigates protein tyrosine phosphatase 1B (PTP1B) and the α-glucosidase inhibitory activities of two edible brown algae,
Ecklonia stolonifera and
Eisenia bicyclis, as well as in their isolated phlorotannins. Since the individual extracts and fractions showed significant inhibitory activities, column chromatography was performed to isolate six phlorotannins, phloroglucinol (1), dioxinodehydroeckol (2), eckol (3), phlorofurofucoeckol-A (4), dieckol (5), and 7-phloroeckol (6). Phlorotannins 3–6 were potent and noncompetitive PTP1B inhibitors with IC
50 values ranging from 0.56 to 2.64 μ
M; 4–6 exhibited the most potent α-glucosidase inhibition with IC
50 values ranging from 1.37 to 6.13 μ
M. Interestingly, 4 and 6 were noncompetitive, while 5 exhibited competitive inhibition in an α-glucosidase assay.
E. stolonifera and
E. bicyclis as well as their isolated phlorotannins therefore possessed marked PTP1B and α-glucosidase inhibitory activities; this could lead to opportunities in the development of therapeutic agents to control the postprandial blood glucose level and thereby prevent diabetic complications.
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Toshiyuki NAKAMURA, Ryohei TANAKA, Hitoshi ASHIDA
2011 Volume 75 Issue 8 Pages
1506-1510
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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β-Glucuronidase and sulfatase are the major deconjugating enzymes used in the cleavage of the glucuronate and sulfate moieties, respectively, from certain conjugated food factors including polyphenols. In the present study, we found that compounds having the same molecular weights as catechins were present in
Helix pomatia- and/or
Abalone entrails-derived β-glucuronidase and sulfatase by liquid chromatography tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring methods. On the other hand, the same molecular weights as catechins were undetectable in
Escherichia coli-derived β-glucuronidase and
Aerobacter aerogenes-derived sulfatase. By high performance liquid chromatography, enzyme-derived catechins were not detected because of approximately 1,000-fold lower sensitivity as compared to LC-MS/MS. These results suggest that the catechins in these enzymes might be attributed to the diets of the organisms as the enzyme sources.
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Ritsuro IDETA, Tomohiro SAKUTA, Yusuke NAKANO, Taro UCHIYAMA
2011 Volume 75 Issue 8 Pages
1516-1523
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Dietary glucosylceramide improves the skin barrier function. We used a microarray system to analyze the mRNA expression in SDS-treated dorsal skin of the hairless mouse to elucidate the molecular mechanisms involved. The transepidermal water loss of mouse skin was increased by the SDS treatment, this increase being significantly reduced by a prior oral administration of glucosylceramides. The microarray-evaluated mRNA expression ratio showed a statistically significant increase in the expression of genes related to the cornified envelope and tight junction formation when compared with all genes in the glucosylceramide-fed/SDS-treated mouse skin. We then examined the contribution of glucosylceramide metabolites to the tight junction formation of cultured keratinocytes. The SDS treatment of cultured keratinocytes significantly decreased the transepidermal electrical resistance, this decrease being significantly ameliorated in the presence of sphingosine or phytosphingosine, the major metabolites of glucosylceramide. These results suggest that an oral administration of glucosylceramide improved the skin barrier function by up-regulating genes associated with both the cornified envelope and tight junction formation.
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Ken-ichiro NAKAJIMA, Ayako KOIZUMI, Kisho IIZUKA, Keisuke ITO, Yuji MO ...
2011 Volume 75 Issue 8 Pages
1600-1602
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Neoculin, a sweet protein found in the fruit of
Curculigo latifolia, has the ability to change sourness into sweetness. Neoculin turns drinking water sweet, indicating that non-acidic compounds may induce the sweetness. We report that ammonium chloride and certain amino acids elicit the intense sweetness of neoculin. Neoculin can thus sweeten amino acid-enriched foods.
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Hiroko TAKUMI, Rie MUKAI, Sawako ISHIDUKA, Takashi KOMETANI, Junji TER ...
2011 Volume 75 Issue 8 Pages
1608-1610
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Hesperetin, the aglycone of hesperidin present in citrus fruits, possesses various biological activities. We assessed the tissue distribution of hesperetin in rats fed with a 0.2% hesperetin diet for 4 weeks. Its highest concentration was found in the liver, and the second highest was in the aorta. The aorta is assumed to be one of the main target tissues of hesperetin for exerting its functions.
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Haruya TAKAHASHI, Young-Il KIM, Shizuka HIRAI, Tsuyoshi GOTO, Chie OHY ...
2011 Volume 75 Issue 8 Pages
1621-1624
Published: August 23, 2011
Released on J-STAGE: August 23, 2011
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Peroxisome proliferator-activated receptor-α (PPARα) regulates lipid metabolism. We have reported that tomato fruit contains 9-Oxo-(10
E,12
E)-octadecadienoic acid (9-Oxo-(10
E,12
E)-ODA), a PPARα agonist. In this study, we found that various tomato samples contained 9-Oxo-(10
E,12
Z)-ODA and its 13-Oxo-ODA isomers. Furthermore, several isomers showed structural stability under hot and acidic conditions.
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Jing WU, Keiji FUSHIMI, Shinji TOKUYAMA, Masato OHNO, Takaaki MIWA, To ...
2011 Volume 75 Issue 8 Pages
1631-1634
Published: August 23, 2011
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Nine compounds (
1–
9) were isolated from the fruiting bodies of
Stropharia rugosoannulata. Compounds
1–
5,
8, and
9 suppressed the formation of osteoclast. Compounds
2 and
5 showed anti-fungal activity, and their MIC were 250 μ
M and 500 μ
M respectively. Compounds
2–
6 showed inhibitory effects on thapsigargin toxicity.
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