Makoto Ojika

Nagoya University, Nagoya, Aichi, Japan

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Publications (187)503.26 Total impact

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    ABSTRACT: In order to elucidate the chemical structure of black to brown pigments, neuromelanins (NMs), in the substantia nigra (SN) and the locus coeruleus (LC) in the central nervous system of humans and other mammalian species during aging, chemical degradative methods are powerful tools. HPLC analysis after hydroiodic acid hydrolysis detected aminohydroxyphenylethylamines, aminohydroxyphenylacetic acids, and aminohydroxyethylbenzenes, which confirmed that SN-NM and LC-NM contain melanin derived not only from dopamine and norepinephrine (NE) but also from several other catecholic metabolites, such as 3,4-dihydroxyphenylalanine, 3,4-dihydroxyphenylacetic acid, 3,4-dihydroxymandelic acid, 3,4-dihydroxyphenylethanol, and 3,4-dihydroxyphenylethylene glycol, in addition to the corresponding Cys-derivatives in varying degrees. However, hydroiodic acid hydrolysis showed that LCNM produced the same degradation products as were detected in SN-NM. Thus, we needed to develop a new chemical detection method to validate the existence of NE in LC-NM. In the present study, we report that HCl hydrolysis of LC-NM in the presence of thioglycolic acid yields new products arising from substitution of the hydroxyl group by thioglycolic acid at the benzyl position of NE and cysteinyl-NE. This is the first chemical evidence showing that NE and cysteinyl-NE are incorporated into LC-NM.
    Journal of Neurochemistry 11/2015; 135(4):768-76. DOI:10.1111/jnc.13237 · 4.28 Impact Factor
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    ABSTRACT: Pradimicin A (PRM-A) is a unique antibiotic with a lectin-like ability to bind d-mannose (d-Man) in the presence of Ca(2+) ion. Although accumulated evidences suggest that PRM-A recognizes the 2-, 3-, and 4-hydroxyl groups of d-Man, BMY-28864, an artificial PRM-A derivative, was shown not to bind l-fucose (l-Fuc) and l-galactose (l-Gal), both of which share the characteristic array of the three hydroxyl groups with d-Man. To obtain a plausible explanation for this inconsistency, we performed co-precipitation experiments of PRM-A with l-Fuc, l-Gal, and their methyl pyranosides (l-Fuc-OMe, l-Gal-OMe) by taking advantage of aggregate-forming propensity of the binary [PRM-A/Ca(2+)] complex. While l-Fuc and l-Gal were hardly incorporated into the aggregate, l-Fuc-OMe and l-Gal-OMe were found to exhibit significant binding to PRM-A. However, increased Ca(2+) concentration abolished this binding, raising the possibility that poor binding of l-Fuc and l-Gal to PRM-A is attributed to their chelation with Ca(2+) ion. This possibility was partly supported by (1)H NMR analysis that detected interaction of l-Fuc and l-Gal with Ca(2+) ion in aqueous solution. These results collectively indicate that PRM-A binds pyranosides of l-Fuc and l-Gal when Ca(2+) concentration is not excessive to trap these sugars by chelation but sufficient to form the [PRM-A/Ca(2+)] complex. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Bioorganic & medicinal chemistry letters 05/2015; 25(15). DOI:10.1016/j.bmcl.2015.05.021 · 2.42 Impact Factor
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    ABSTRACT: Four maleic anhydride derivatives, tricladolides A-D (1-4), and three alkylidene succinic acid derivatives, tricladic acids A-C (5-7), were isolated from the aquatic hyphomycete Tricladium castaneicola. The structures of these compounds were determined by spectroscopic analysis, and all were found to be novel. The compounds exhibited inhibitory activity against fungi, particularly Phytophthora sp., a plant pathogen of oomycetes. The inhibitory activity of these metabolites revealed the importance of the cyclic anhydride structure and the lipophilicity of the alkyl side chain. On the other hand, the cytotoxicity of the compounds against B16 melanoma cells indicated that the cyclic anhydride structure was not essential.
    Journal of Natural Products 04/2015; 78(4). DOI:10.1021/np500773s · 3.80 Impact Factor
  • Lei Dong · Xiangyuan Zhu · Haichen Cui · Makoto Ojika · Ruigang Wang · Huirong Liu ·
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    ABSTRACT: Phytophthora infestans is the most devastating pathogen of potato. For the biology study of P. infestans at the molecular level, one of the difficulties is the technique for the genetic transformation. In this study, the straightforward electro-transformation system was established for P. infestans with a green fluorescent protein expression vector and compared with the improved PEG/CaCl2 mediated protoplast transformation system. The results showed that the straightforward electro-transformation could work in P. infestans and 32 positive transformants were obtained per about 1.10×10(6) zoospores. The transformants per μg of vector DNA was 1.08. The transformation efficiency of the straightforward electro-transformation was approximately 2 times higher than that of the improved PEG/CaCl2 mediated protoplast transformation (17 positive transformants per about 1.05×10(6) protoplasts, 0.58 transformants per μg of vector DNA) according to the reported procedures. Furthermore, compared with the improved PEG/CaCl2 transformation, the straightforward electroporation is simpler and requires less starting materials and operating time from collecting material to obtaining the resistant transformants. Our work will lay a foundation for the biology study of P. infestans in the future. Copyright © 2015. Published by Elsevier B.V.
    Journal of microbiological methods 03/2015; 112. DOI:10.1016/j.mimet.2015.03.013 · 2.03 Impact Factor
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    ABSTRACT: RS-4-(4-Hydroxyphenyl)-2-butanol (rhododendrol, RD) was reported to induce leukoderma of the skin. To explore the mechanism underlying that effect, we previously showed that oxidation of RD with mushroom tyrosinase produces RD-quinone, which is converted to secondary quinone products, and we suggested that those quinones are cytotoxic since they bind to cellular proteins and produce reactive oxygen species. We then confirmed that human tyrosinase can oxidize both enantiomers of RD. In this study, we examined the metabolism of RD in B16F1 melanoma cells in vitro. Using 4-amino-3-hydroxy-n-butylbenzene as a specific indicator, we detected moderate levels of RD-pheomelanin in B16F1 cells exposed to 0.3 to 0.5 mM RD for 72 h. We also confirmed the covalent binding of RD-quinone to non-protein thiols and proteins through cysteinyl residues. The covalent binding of RD-quinone to proteins was 20 to 30-fold greater than dopaquinone. These results suggest that the tyrosinase-induced metabolism of RD causes melanocyte toxicity. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
    Pigment Cell & Melanoma Research 02/2015; 28(3). DOI:10.1111/pcmr.12363 · 4.62 Impact Factor
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    ABSTRACT: Plants recognize certain microbial compounds as elicitors in their active defence mechanisms. It has been shown that a series of defence reactions are induced in potato plant cells after treatment with water-soluble hyphal wall components prepared from Phytophthora infestans. In this study, a methanol extract from mycelia of P. infestans (MEM), which contains lipophilic compounds, was used as another elicitor for the induction of the defence reactions in potato. MEM elicitor induced reactive oxygen species (ROS), especially O2(-) and H2O2 production, and nitric oxide (NO) generation in potato leaves and suspension-cultured cells. Hypersensitive cell death was detected in potato leaves within 6-8h after MEM elicitor treatment. The accumulation of phytoalexins was detected by MEM elicitor treatment in potato tubers. In potato suspension-cultured cells, several defence-related genes were induced by MEM elicitors, namely Strboh, Sthsr203J, StPVS3, StPR1, and StNR5, which regulate various defence-related functions. Enhanced resistance against P. infestans was found in MEM-treated potato plants. These results suggested that MEM elicitor is recognized by host and enhances defence activities to produce substances inhibitory to pathogens. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.
    Comptes Rendus Biologies 02/2015; 338(3). DOI:10.1016/j.crvi.2015.01.004 · 0.98 Impact Factor
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    ABSTRACT: Mature Nicotiana benthamiana shows stable resistance to the oomycete pathogen Phytophthora infestans. Induction of phytoalexin (capsidiol) production is essential for the resistance, which is up-regulated via a MAPK cascade (NbMEK2-WIPK/SIPK) followed by ethylene signaling. In this study, NbNup75 (encodes a nuclear pore protein Nucleoporin75) was identified as an essential gene for resistance of N. benthamiana to P. infestans. In NbNup75-silenced plants, initial events of elicitor-induced responses such as phosphorylation of MAPKs and expression of defense-related genes were not affected, while induction of later defense responses such as capsidiol production and cell death induction was suppressed or delayed. Ethylene production induced by either INF1 or NbMEK2 was reduced in NbNup75-silenced plants, whereas the expression of NbEAS (a gene for capsidiol biosynthesis) induced by ethylene was not affected, indicating that Nup75 is required for the induction of ethylene production, but not for ethylene signaling. Given that nuclear accumulation of polyA RNA was increased in NbNup75-silenced plants, efficient export of mRNA from nuclei via nuclear pores would be important for the timely up-regulation of defense responses. Collectively, Nup75 is involved in the induction of later stage of defense responses including the ethylene-mediated production of phytoalexin for the resistance of N. benthamiana to P. infestans.
    Molecular Plant-Microbe Interactions 08/2014; 27(12). DOI:10.1094/MPMI-06-14-0181-R · 3.94 Impact Factor
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    ABSTRACT: One of the current obstacles to stem cell therapy is the tumorigenic potential of residual undifferentiated stem cells. The present study reports rediscovery of a synthetic derivative of okadaic acid, a marine polyether toxin, as a reagent that selectively induces the death of human pluripotent stem cells. Cell-based screening of 333 cytotoxic compounds identified methyl 27-deoxy-27-oxookadaate (molecule 1) as a substrate of two ATP-binding cassette (ABC) transporters, ABCB1 (MDR1) and ABCG2 (BCRP), whose expression is repressed in human embryonic stem cells and induced pluripotent stem cells. The results demonstrate that selective elimination of human pluripotent stem cells can be achieved by designing cytotoxic small molecules with appropriate ABC-transporter selectivity.
    Journal of the American Chemical Society 07/2014; 136(28). DOI:10.1021/ja501795c · 12.11 Impact Factor
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    ABSTRACT: Racemic RS-4-(4-hydroxyphenyl)-2-butanol (rhododendrol, RD) was used as a topical skin whitening agent until it was recently reported to induce leukoderma. We then showed that oxidation of RD with mushroom tyrosinase rapidly produces RD-quinone, which is quickly converted to RD-cyclic quinone and RD-hydroxy-p-quinone. In this study, we examined whether either or both of the enantiomers of RD can be oxidized by human tyrosinase. Using a chiral HPLC column, racemic RD was resolved optically to R(-)-RD and S(+)-RD enantiomers. In the presence of a catalytic amount of L-dopa, human tyrosinase, which can oxidize L-tyrosine but not D-tyrosine, was found to oxidize both R(-)- and S(+)-RD to give RD-catechol and its oxidation products. S(+)-RD was more effectively oxidized than L-tyrosine while R(-)-RD was less effective. These results support the notion that the melanocyte toxicity of RD depends on its tyrosinase-catalyzed conversion to toxic quinones and the concomitant production of reactive oxygen species.This article is protected by copyright. All rights reserved.
    Pigment Cell & Melanoma Research 07/2014; 27(6). DOI:10.1111/pcmr.12300 · 4.62 Impact Factor
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    ABSTRACT: Neuromelanin (NM) is produced in dopaminergic neurons of the substantia nigra (SN) and in noradrenergic neurons of the locus coeruleus (LC). The synthesis of NM in those neurons is a component of brain aging and there is the evidence that this pigment can be involved in the pathogenesis of neurodegenerative diseases such as Parkinson's disease. NM is believed to derive from the oxidative polymerization of dopamine (DA) or norepinephrine (NE) with the participation of cysteine, dolichols and proteins. However, there are still unknown aspects in the chemical structure of NM from SN (SN-NM) and LC (LC-NM). In this study, we designed a new method to synthesize o-aminophenol compounds as putative degradation products of catecholamines and their metabolites which may be incorporated into NM. Those compounds are aminohydroxyphenylethylamine (AHPEA) isomers, aminohydroxyphenylacetic acid (AHPAA) isomers and aminohydroxyethylbenzene (AHEB) isomers, which are expected to arise from DA or NE, 3,4-dihydroxyphenylacetic acid (DOPAC) or 3,4-dihydroxyphenylmandelic acid (DOMA) and 3,4-dihydroxyphenylethanol (DOPE) or 3,4-dihydroxyphenylethyleneglycol (DOPEG), respectively. These o-aminophenol compounds were synthesized by the nitration of phenol derivatives followed by reduction with hydroiodic acid (HI), and they could be identified by HPLC in HI hydrolysates of SN-NM and LC-NM. This degradative approach by HI hydrolysis allows the identification of catecholic precursors unique to SN-NM and LC-NM, which are present in catecholaminergic neurons.
    Molecules 06/2014; 19(6):8039-50. DOI:10.3390/molecules19068039 · 2.42 Impact Factor
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    ABSTRACT: RS-4-(4-Hydroxyphenyl)-2-butanol (rhododendrol, RD) was used as a skin whitening agent until it was reported to induce leukoderma in July, 2013. To explore the mechanism underlying its melanocyte toxicity, we characterized the tyrosinase-catalyzed oxidation of RD using spectrophotometry and HPLC. Oxidation of RD with mushroom tyrosinase rapidly produced RD-quinone, which was quickly converted to 2-methylchromane-6,7-dione (RD-cyclic quinone) and RD-hydroxy-p-quinone through cyclization and addition of water molecule, respectively. RD-quinone and RD-cyclic quinone were identified as RD-catechol and RD-cyclic catechol after NaBH4 reduction. Autoxidation of RD-cyclic catechol produced superoxide radical. RD-quinone and RD-cyclic quinone quantitatively bound to thiols such as cysteine and GSH. These results suggest that the melanocyte toxicity of RD is caused by its tyrosinase-catalyzed oxidation through production of RD-cyclic quinone which depletes cytosolic GSH and then binds to essential cellular proteins through their sulfhydryl groups. The production of ROS through autoxidation of RD-cyclic catechol may augment the toxicity. (148 words) This article is protected by copyright. All rights reserved.
    Pigment Cell & Melanoma Research 06/2014; 27(5). DOI:10.1111/pcmr.12275 · 4.62 Impact Factor
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    Yuichi Oba · Naoki Yoshida · Shusei Kanie · Makoto Ojika · Satoshi Inouye ·
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    ABSTRACT: Bioluminescence in fireflies and click beetles is produced by a luciferase-luciferin reaction. The luminescence property and protein structure of firefly luciferase have been investigated, and its cDNA has been used for various assay systems. The chemical structure of firefly luciferin was identified as the D-form in 1963 and studies on the biosynthesis of firefly luciferin began early in the 1970's. Incorporation experiments using (14)C-labeled compounds were performed, and cysteine and benzoquinone/hydroquinone were proposed to be biosynthetic component for firefly luciferin. However, there have been no clear conclusions regarding the biosynthetic components of firefly luciferin over 30 years. Incorporation studies were performed by injecting stable isotope-labeled compounds, including L-[U-(13)C3]-cysteine, L-[1-(13)C]-cysteine, L-[3-(13)C]-cysteine, 1,4-[D6]-hydroquinone, and p-[2,3,5,6-D]-benzoquinone, into the adult lantern of the living Japanese firefly Luciola lateralis. After extracting firefly luciferin from the lantern, the incorporation of stable isotope-labeled compounds into firefly luciferin was identified by LC/ESI-TOF-MS. The positions of the stable isotope atoms in firefly luciferin were determined by the mass fragmentation of firefly luciferin. We demonstrated for the first time that D- and L-firefly luciferins are biosynthesized in the lantern of the adult firefly from two L-cysteine molecules with p-benzoquinone/1,4-hydroquinone, accompanied by the decarboxylation of L-cysteine.
    PLoS ONE 12/2013; 8(12):e84023. DOI:10.1371/journal.pone.0084023 · 3.23 Impact Factor
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    ABSTRACT: Using B16 melanoma cells for screening, we found that a marine sponge extract has a potent anti-pigmenting effect and identified arenarol as its major active compound. In normal human melanocytes (NHMs), arenarol significantly abrogated the endothelin 1 (EDN1) stimulated expression of tyrosinase, tyrosinase-related protein 1 and dopachrome tautomerase at the transcriptional, translational and enzymatic activity (only for tyrosinase) levels. That effect was accompanied by the attenuation of the increased expression level of microphthalmia-associated transcription factor (MITF) protein at the transcriptional and translational levels. Analysis of EDN1 signaling demonstrated that arenarol significantly suppressed the EDN1-induced phosphorylation of MEK, ERK, MITF and CREB but not of Raf-1s. In contrast, the forskolin-induced phosphorylation of CREB was not down-regulated by arenarol. As for the mode of action of the suppressed phosphorylation of MEK, Raf-1 activity was not directly inhibited by arenarol in vitro and pretreatment with the protein phosphatase inhibitor okadaic acid did not affect the down-regulated phosphorylation of MEK that was induced by arenarol in NHMs. The sum of these findings suggests that arenarol abrogates the EDN1-stimulated expression of melanocyte-specific proteins by interrupting MEK phosphorylation in an as yet unknown Raf-1 inactivation mechanism.
    Cytotechnology 05/2013; 65(6). DOI:10.1007/s10616-013-9555-5 · 1.75 Impact Factor
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    ABSTRACT: Mature Nicotiana benthamiana shows strong resistance to the potato late blight pathogen Phytophthora infestans. By screening using virus-induced random gene silencing, we isolated a gene for plant-specific calreticulin NbCRT3a as a required gene for resistance of N. benthamiana against P. infestans. NbCRT3a encodes an ER quality-control (ERQC) chaperone for the maturation of glycoproteins, including glycosylated cell-surface receptors. NbCRT3a-silenced plants showed no detectable growth defects, but resistance to P. infestans was significantly compromised. Defense responses induced by the treatment with INF1 (a secretory protein of P. infestans), such as production of reactive oxygen species (ROS) and accumulation of phytoalexins, were suppressed in NbCRT3a-silenced N. benthamiana. Expression of an ethylene-regulated gene for phytoalexin biosynthesis, NbEAS, was reduced in NbCRT3a-silenced plants, whereas the expression of salicylic acid-regulated NbPR-1a was not affected. Consistently, induction of ethylene production by INF1 was suppressed in NbCRT3a-silenced plants. Resistance reactions induced by hyphal wall components (HWC) elicitor prepared from P. infestans were also impaired in NbCRT3a-silenced plants. However, cell death induced by active MAPKK (NbMEK2(DD)) was not affected by the silencing of NbCRT3a. NbCRT3a is thus required for the initiation of resistance reactions of N. benthamiana in response to elicitor molecules derived from P. infestans.
    Molecular Plant-Microbe Interactions 04/2013; 26(8). DOI:10.1094/MPMI-12-12-0301-R · 3.94 Impact Factor
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    ABSTRACT: Platelet-derived growth factor (PDGF) induces the proliferation and migration of vascular smooth muscle cells (VSMCs), leading to the development of various vascular disorders such as restenosis and atherosclerosis. Therefore, inhibitors of PDGF-induced cellular events would be candidate agents for treating these diseases. During the search for such inhibitors from marine sources, we isolated petrosiols A-D (1-4) and related compounds from the marine sponge Petrosia strongylata. These metabolites, which we previously reported as neurotrophic substances, showed an inhibitory effect on PDGF-induced DNA synthesis at IC(50) values of 0.69-2.2μM. Petrosiol A (1) inhibited PDGF-induced cell proliferation without remarkable cytotoxicity and arrested cell cycle progression from the G0/G1 to S phase by inducing the downregulation of the expression of G1 checkpoint proteins cyclin D1, cyclin E, cyclin-dependent kinases (CDK)2, and CDK4 and the upregulation of the expression of p21 and p27. In addition, petrosiol A (1) inhibited the phosphorylation of PDGF receptor-β and its downstream proteins such as phospholipase C (PLC)-γ1, Akt, and extracellular signal-regulated kinase (ERK)1/2. These results suggest that 1 inhibited PDGF-induced VSMC proliferation by interrupting the phosphorylation of PDGF receptor-β followed by downstream signal transduction. Furthermore, petrosiol A (1) suppressed PDGF-induced actin filament dissociation and cell migration, suggesting that 1 and its derivatives may be used for the prevention and treatment of vascular diseases.
    Bioorganic & medicinal chemistry 01/2013; 21(7). DOI:10.1016/j.bmc.2013.01.039 · 2.79 Impact Factor
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    ABSTRACT: From an extract of the Okinawan sponge Petrosia strongylata, five novel acetylenic metabolites, petrosiols A (1)–E (5), were isolated and chemically characterized. These compounds induced nerve growth factor (NGF)-like neuronal differentiation of PC12 cells. The structure–activity relationships of the petrosiols, their derivatives, and some related known compounds suggest the importance of the rare 2,4-diyne-1,6,7,8-tetraol fragment for the neurotrophic activity of the petrosiols.
    Tetrahedron 01/2013; 69(1):101–106. DOI:10.1016/j.tet.2012.10.063 · 2.64 Impact Factor
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    ABSTRACT: The novel cerebroside, termitomycesphin I (1), and two known cerebrosides (2 and 3) were isolated from the edible mushroom, Termitomyces titanicus. The structures of 1-3 were determined and identified by interpreting the spectroscopic data.
    Bioscience Biotechnology and Biochemistry 07/2012; 76(7):1407-9. DOI:10.1271/bbb.120130 · 1.06 Impact Factor
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    ABSTRACT: Metastatic melanoma is resistant to conventional therapies. N-propionyl-4-S-cysteaminylphenol (NPrCAP), an N-protected sulfur-amine analog of tyrosine, is a good substrate for tyrosinase and is selectively incorporated into melanoma cells, causing cytotoxicity in vitro and in vivo. We have recently shown that intratumoral injections of NPrCAP suppress not only the growth of primary B16F1 melanoma tumors but also of secondary, re-challenged tumors. The participation of CD8(+) T cells has been suggested for the NPrCAP-mediated anti-B16 melanoma immunity. In this study, the molecular mechanism of the NPrCAP cytotoxicity and immunogenicity was examined. The phenol NPrCAP was shown to be activated by mushroom tyrosinase to the ortho-quinone N-propionyl-4-S-cysteaminyl-1,2-benzoquinone (NPrCAQ), and the structure was confirmed by reducing it to the corresponding catechol. NPrCAQ reacted rapidly with biologically relevant sulfhydryl compounds such as cysteine, glutathione and bovine serum albumin. The NPrCAQ-thiol adduct formation was proven with a model thiol N-acetylcysteine by spectroscopic methods. The production and release of NPrCAQ-protein adducts was verified in B16F1 melanoma cells in vitro and in B16F1 melanoma-bearing mice in vivo through the detection of 5-S-cysteaminyl-3-S-cysteinylcatechol after acid hydrolysis of the protein fraction. These results suggest that the phenol NPrCAP, acting as a prohapten, can be activated in melanoma cells by tyrosinase to the quinone-hapten NPrCAQ, which binds to melanosomal proteins through their cysteine residues to form possible neo-antigens, thus triggering the immunological response. NPrCAP thus represents a potential new approach to immunotherapy against metastatic melanoma.
    Biochemical pharmacology 06/2012; 84(5):646-53. DOI:10.1016/j.bcp.2012.06.015 · 5.01 Impact Factor
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    ABSTRACT: A library of extracts established from hundreds of marine organisms was screened by a cytotoxicity test. The active organic extract of an Okinawan marine sponge of the genus Dysidea was subjected to bioassay-guided fractionation to give three new polyoxygenated steroids dysideasterols F-H (1-3), together with two known related compounds (4 and 5). Their structures were confirmed by NMR and mass spectroscopic analyses. A characteristic structural feature of 2, 4 and 5 is an allylic epoxide, whereas this epoxide undergoes ring-opening by a neighbouring hydroxyl group to give a tetrahydrofuran ring in 1 and 3. All compounds 1-5 exhibited a similar cytotoxic effect with IC50 values of 0.15-0.3 µM against human epidermoid carcinoma A431 cells, demonstrating that the allylic epoxide moiety was not responsible for this cytotoxic effect.
    Bioscience Biotechnology and Biochemistry 05/2012; 76(5):999-1002. DOI:10.1271/bbb.120017 · 1.06 Impact Factor
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    ABSTRACT: Two new cerebrosides, termitomycesphins G and H, were isolated from the edible Chinese mushroom, Termitomyces albuminosus (Berk.) Herm., and exhibited neuritogenic activity against PC12 cells. Their structures and absolute stereochemistry were elucidated by spectroscopic methods and by a comparison of the specific rotation of the hydrogenated products from termitomycesphins H and C. These cerebrosides possessed a unique modification by a hydroxyl group at the middle of the long-chain base, like earlier congeners termitomycesphins A-F. Termitomycesphin G with a 16-carbon-chain fatty acid showed higher neuritogenic activity than that of termitomycesphin H with an 18-carbon-chain fatty acid. This effect was observed within the termitomycesphins, suggesting that the chain length of the fatty acyl moiety played a key role in the neuritogenic activity.
    Bioscience Biotechnology and Biochemistry 04/2012; 76(4):791-3. DOI:10.1271/bbb.110918 · 1.06 Impact Factor

Publication Stats

3k Citations
503.26 Total Impact Points


  • 1981-2015
    • Nagoya University
      • • Graduate School of Bio-Agricultural Sciences
      • • Department of Applied Molecular Biosciences
      • • Department of Chemistry
      Nagoya, Aichi, Japan
  • 2010
      Edo, Tōkyō, Japan
  • 2007
    • Kumamoto University
      Kumamoto, Kumamoto Prefecture, Japan
  • 1984
    • The University of Tokyo
      • Institute of Medical Science
      白山, Tōkyō, Japan