804 results on '"Suzuki, Nobutaka"'
Search Results
502. Chemiluminescence Developed at An Early Stage of the Maillard Reaction
- Author
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Namiki, Mitsuo, Oka, Michiko, Otsuka, Miki, Miyazawa, Teruo, Fujimoto, Kenshiro, Namiki, Kazuko, Kanamori, Norio, and Suzuki, Nobutaka
- Published
- 1998
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503. Chemiluminescent Products of the Maillard Reaction: Studies on Model Systems
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Suzuki, Nobutaka, Hatate, Hideo, Mizumoto, Iwao, and Namiki, Mitsuo
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- 1998
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504. Comparison of protease activity in liver among several species of squid and cuttlefish.
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Hatate, Hideo, Tanaka, Ryusuke, Suzuki, Nobutaka, and Hama, Yoichiro
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PROTEOLYTIC enzymes , *SQUIDS , *CUTTLEFISH , *INDUSTRIAL enzymology - Abstract
Presents a study which compared protease activity in liver among several species of squid and cuttlefish. Industrial uses of enzyme preparations originating from micro-organisms; Effectiveness of squid proteases in food processing; Differences in the freshness of the species.
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- 2000
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505. Two chalcones, 4-hydroxyderricin and xanthoangelol, stimulate GLUT4-dependent glucose uptake through the LKB1/AMP-activated protein kinase signaling pathway in 3T3-L1 adipocytes.
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Ohta, Mitsuhiro, Fujinami, Aya, Kobayashi, Norihiro, Amano, Akiko, Ishigami, Akihito, Tokuda, Harukuni, Suzuki, Nobutaka, Ito, Fumitake, Mori, Taisuke, Sawada, Morio, Iwasa, Koichi, Kitawaki, Jo, Ohnishi, Katsunori, Tsujikawa, Muneo, and Obayashi, Hiroshi
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ADIPOSE tissue physiology , *GLUCOSE metabolism , *CELL membranes , *CELLULAR signal transduction , *ENZYMES , *MEDICINAL plants , *IN vitro studies - Abstract
4-Hydroxyderricin (4HD) and xanthoangelol (XAG) are major components of n-hexane/ethyl acetate (5:1) extract of the yellow-colored stem juice of Angelica keiskei . 4-Hydroxyderricin and XAG have been reported to increase glucose transporter 4 (GLUT4)–dependent glucose uptake in 3T3-L1 adipocytes, but the detailed mechanism of this phenomenon remains unknown. This present study was aimed at clarifying the detailed mechanism by which 4HD and XAG increase GLUT4-dependent glucose uptake in 3T3-L1 adipocytes. Both 4HD and XAG increased glucose uptake and GLUT4 translocation to the plasma membrane. 4-Hydroxyderricin and XAG also stimulated the phosphorylation of 5′ adenosine monophosphate–activated protein kinase (AMPK) and its downstream target acetyl-CoA carboxylase. In addition, phosphorylation of liver kinase B1 (LKB1), which acts upstream of AMPK, was also increased by 4HD and XAG treatment. Small interfering RNA knockdown of LKB1 attenuated 4HD- and XAG-stimulated AMPK phosphorylation and suppressed glucose uptake. These findings demonstrate that 4HD and XAG can increase GLUT4-dependent glucose uptake through the LKB1/AMPK signaling pathway in 3T3-L1 adipocytes. [ABSTRACT FROM AUTHOR]
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- 2015
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506. A-ring modified betulinic acid derivatives as potent cancer preventive agents.
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Hung, Hsin-Yi, Nakagawa-Goto, Kyoko, Tokuda, Harukuni, Iida, Akira, Suzuki, Nobutaka, Bori, Ibrahim D., Qian, Keduo, and Lee, Kuo-Hsiung
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CARCINOGENESIS , *BETULIN , *CANCER prevention , *PHORBOLS , *LABORATORY mice , *CHEMOPREVENTION - Abstract
Ten new 3,4-seco betulinic acid (BA) derivatives were designed and synthesized. Among them, compounds 7–15 exhibited enhanced chemopreventive ability in an in vitro short-term 12-O-tetradecanoylphorbol-13-acetate (TPA) induced Epstein–Barr virus early antigen (EBV-EA) activation assay in Raji cells. Specifically, analogs with a free C-28 carboxylic acid, including 7, 8, 11, and 13, inhibited EBV-EA activation significantly. The most potent compound 8 displayed 100% inhibition at 1×103 molratio/TPA and 73.4%, 35.9%, and 8.4% inhibition at 5×102, 1×102, and 1×10molratio/TPA, respectively, comparable with curcumin at high concentration and better than curcumin at low concentration. The potent chemopreventive activity of novel seco A-ring BAs (8 and 11) was further confirmed in an in vivo mouse skin carcinogenesis assay. [ABSTRACT FROM AUTHOR]
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- 2014
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507. Design, synthesis and structure–activity relationship of novel quinoxaline derivatives as cancer chemopreventive agent by inhibition of tyrosine kinase receptor.
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Galal, Shadia A., Abdelsamie, Ahmed S., Soliman, Salwa M., Mortier, Jeremie, Wolber, Gerhard, Ali, Mamdouh M., Tokuda, Harukuni, Suzuki, Nobutaka, Lida, Akira, Ramadan, Raghda A., and El Diwani, Hoda I.
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STRUCTURE-activity relationship in pharmacology , *QUINOXALINES , *CANCER chemoprevention , *ANTINEOPLASTIC agents , *PROTEIN-tyrosine kinases , *EPSTEIN-Barr virus - Abstract
Abstract: The cancer chemopreventive activity of quinoxaline derivatives 1–20 has been evaluated by studying the inhibitory effect on Epstein–Barr virus early antigen (EBV-EA) activation. The quinoxaline derivatives 1–20 showed inhibitory effect on EBV-EA activation without cytotoxicity on Raji cells. All compounds exhibited dose dependent inhibitory activities, most of them showed significant activity at 1000 mol ratio/12-O-tetradecanoylphorbol-13-acetate (TPA). Compounds 7 and 9 exhibited stronger inhibitory effects on the EBV-EA activation than that of the representative control, oleanolic acid, at the highest measured concentration. In addition, compounds 7–10 showed potent and selective inhibition of human tyrosine kinase (TRK) in liver cancer HepG2 and breast cancer MCF-7 cell lines similar to the positive control, doxorubicin. [Copyright &y& Elsevier]
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- 2013
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508. Structure–activity studies at position 27 of aplog-1, a simplified analog of debromoaplysiatoxin with anti-proliferative activity.
- Author
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Hanaki, Yusuke, Kikumori, Masayuki, Ueno, Sayo, Tokuda, Harukuni, Suzuki, Nobutaka, and Irie, Kazuhiro
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TOXINS , *PROTEIN kinase C , *TUMOR suppressor proteins , *APOPTOSIS , *STRUCTURE-activity relationships , *CANCER cell growth - Abstract
Abstract: Aplog-1, a simplified analog of debromoaplysiatoxin with anti-proliferative activity, bound to and activated protein kinase Cδ (PKCδ), that is involved in tumor suppression and apoptosis. To examine the contribution of PKCδ to the anti-proliferative activity of aplog-1, we synthesized 27-methyl and 27-methoxy derivatives that differed in the ability to activate PKCδ. Activators of PKCδ like aplog-1 and 27-(R)-Me-aplog-1 strongly inhibited the growth of several cancer cell lines. On the other hand, 27-(S)-Me-aplog-1 and 27-O-Me-aplog-1 without the ability to activate PKCδ, exhibited only weak growth inhibitory activity against these cell lines. These results suggest indirectly that the activation of PKCδ might be involved in the anti-proliferative activity of aplog-1 against aplog-sensitive cancer cell lines. [Copyright &y& Elsevier]
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- 2013
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509. Effects of the methoxy group in the side chain of debromoaplysiatoxin on its tumor-promoting and anti-proliferative activities.
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Yanagita, Ryo C., Kamachi, Hiroaki, Kikumori, Masayuki, Tokuda, Harukuni, Suzuki, Nobutaka, Suenaga, Kiyotake, Nagai, Hiroshi, and Irie, Kazuhiro
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METHOXY group , *INDOLE alkaloids , *ANTINEOPLASTIC agents , *COCARCINOGENS , *CANCER cells , *CELL lines , *PROTEIN kinase C - Abstract
Abstract: Debromoaplysiatoxin (DAT) is a tumor promoter isolated from sea hare and exhibits anti-proliferative activity against several cancer cell lines. To clarify key residues that are responsible for its tumor-promoting activity, we focused on the chiral methoxy group in the side chain, whose role had not yet been discussed or examined before. Demethoxy-DAT (8) was derived from DAT and we evaluated its tumor-promoting activity, anti-proliferative activity, and ability to bind to protein kinase C (PKC) isozymes. Compound 8 showed somewhat weaker tumor-promoting activity than that of DAT both in vitro and in vivo, but showed higher anti-proliferative activity against several cancer cell lines. Although the affinity to novel PKC isozymes of 8 was comparable to that of DAT, the affinity to conventional PKC isozymes decreased slightly. These results suggest that the methoxy group of DAT is one of the key residues critical for tumor-promoting activity but not for anti-proliferative activity. Since the methoxy group has little influence on the molecular hydrophobicity, this is the first report showing that structural factors other than hydrophobicity in the side chain of DAT affected its biological activities. [Copyright &y& Elsevier]
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- 2013
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510. Lipase-catalyzed acylation of microbial mannosylerythritol lipids (biosurfactants) and their characterization.
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Recke, Verena K., Beyrle, Catharina, Gerlitzki, Melanie, Hausmann, Rudolf, Syldatk, Christoph, Wray, Victor, Tokuda, Harukuni, Suzuki, Nobutaka, and Lang, Siegmund
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LIPASES , *CATALYSIS , *ACYLATION , *BIOSURFACTANTS , *LIPIDS , *GLYCOCONJUGATES - Abstract
Highlights: [•] In vitro enzymatic modifications of mannosylerythritol lipids. [•] Lipase-catalyzed acylations of MEL-A and MEL-B. [•] Acyl donors: uncommon fatty acids from other biosurfactants. [•] New glycoconjugates lowered the surface tension of water to 27–38mNm−1. [Copyright &y& Elsevier]
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- 2013
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511. New 6-amino-6-deoxy-glycoglycerolipids derived from 2-O-β-d-glucopyranosylglycerol: insights into the structure–activity relationship of glycoglycerolipids as anti-tumor promoters.
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Colombo, Diego, Gagliardi, Clarissa, Vetro, Maria, Ronchetti, Fiamma, Takasaki, Midori, Konoshima, Takao, Suzuki, Nobutaka, and Tokuda, Harukuni
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GLYCEROLIPIDS , *GLYCERIN , *STRUCTURE-activity relationships , *ANTINEOPLASTIC agents , *COCARCINOGENS , *ALTERNATIVE medicine - Abstract
Highlights: [•] 6-Amino-6-deoxyglycoglycerolipids based on 2-O-β-d-glucosylglycerol were synthesized. [•] Compounds were tested for their in vitro and in vivo anti-tumor-promoting activity. [•] Compounds resulted less active than previously studied glycoglycerolipids. [•] The presence of the nitrogen atom strongly reduced the activity of the compounds. [•] In general 6-position of the sugar plays a crucial role in glycoglycerolipid activity. [Copyright &y& Elsevier]
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- 2013
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512. Structure–activity studies on the side chain of a simplified analog of aplysiatoxin (aplog-1) with anti-proliferative activity.
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Kamachi, Hiroaki, Tanaka, Keisuke, Yanagita, Ryo C., Murakami, Akira, Murakami, Kazuma, Tokuda, Harukuni, Suzuki, Nobutaka, Nakagawa, Yu, and Irie, Kazuhiro
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CELL proliferation , *PROTEIN kinase C , *MOLECULAR probes , *CANCER cell growth , *EPSTEIN-Barr virus , *CYANOBACTERIAL toxins - Abstract
Abstract: We have recently developed a simplified analog of aplysiatoxin (aplog-1) as an activator of protein kinase C (PKC) with anti-proliferative activity like bryostain 1. To identify sites in aplog-1 that could be readily modified to optimize therapeutic performance and to develop a molecular probe for examining the analog’s mode of action, substituent effects on the phenol ring were systematically examined. Whereas hydrophilic acetamido derivatives were less active than aplog-1 in inhibiting cancer cell growth and binding to PKCδ, introduction of hydrophobic bromine and iodine atoms enhanced both biological activities. The anti-proliferative activity was found to correlate closely with molecular hydrophobicity, and maximal activity was observed at a log P value of 4.0–4.5. On the other hand, an induction test with Epstein–Barr virus early antigen demonstrated that these derivatives have less tumor-promoting activity in vitro than aplog-1 regardless of the hydrophobicity of their substituents. These results would facilitate rapid preparation of molecular probes to examine the mechanism of the unique biological activities of aplog-1. [Copyright &y& Elsevier]
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- 2013
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513. Enzymatic production of modified 2-dodecyl-sophorosides (biosurfactants) and their characterization.
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Recke, Verena Kerstin, Gerlitzki, Melanie, Hausmann, Rudolf, Syldatk, Christoph, Wray, Victor, Tokuda, Harukuni, Suzuki, Nobutaka, and Lang, Siegmund
- Abstract
Alkyl sophorosides, a special type of sophorolipids, can be produced using Candida bombicola cultures with glucose as main carbon source and 2-dodecanol as co-substrate. The dominating component, 2-dodecyl-sophoroside SL-E2-12, was purified via medium pressure liquid chromatography (MPLC) and used as substrate for further enzymatic modifications. Using β-glucuronidase in aqueous media the first modification gave a glycosidic cleavage of the acetyl glucose unit leading to 2-dodecyl-glucoside GL-A2-12. In a subsequent lipase-catalyzed acylation with sebacic acid in toluene this compound was functionalized regioselectively at the primary C-6′ position of glucose. Similar lipase-catalyzed reactions in toluene, but now using SL-E2-12 as acyl acceptor and unusual hydroxyl fatty acids - 3-hydroxy decanoic acid and 17-hydroxy stearic acid - as acyl donors, resulted in mono- and diacylations of primary hydroxyl positions of the sophorose unit (C-6′ and C-6′′) as shown by NMR and MS studies. In physicochemical characterization experiments the new glycoconjugates lowered the surface tension of water from 72 to 27-32 mN/m. Moreover it was observed that the new products inhibit the growth of particular Gram-positive bacteria. Additionally they indicate potential for anti-tumor promoting activity. Practical applications: According to literature data 2-alkyl-sophorosides can be produced using Candida bombicola cultures with yields of more than 20 g/L. Based on this starting material, 2-dodecyl-sophoroside, several regioselective enzymatic modifications were performed. Initially, β-glucuronidase catalysis in aqueous buffer solution gave 2-dodecyl-glucoside which was then successfully acylated at the C-6 position of glucose by lipase catalysis using a common dicarboxylic acid, sebacic acid. The resulting free carboxylic function of the acidic derivative opens up the possibility of achieving additional chemo-enzymatic reactions at this position for conversion, for instance, into polyesters. In addition lipase catalysis in organic solvents of 2-dodecyl-sophoroside allows acylation with unusual hydroxyl fatty acids of microbial origin. Physicochemical studies showed that these new glycoconjugates may be of interest for the cosmetic industry due to moisture conservation of the skin. For practical applications the conditions of the above biocatalytic reactions have been improved and scaled up. [ABSTRACT FROM AUTHOR]
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- 2013
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514. Synthesis and structure--activity studies of simplified analogues of aplysiatoxin with antiproliferative activity like bryostatin-1.
- Author
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Irie, Kazuhiro, Kikumori, Masayuki, Kamachi, Hiroaki, Tanaka, Keisuke, Murakami, Akira, Yanagita, Ryo C., Tokuda, Harukuni, Suzuki, Nobutaka, Nagai, Hiroshi, Suenaga, Kiyotake, and Nakagawa, Yu
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STRUCTURE-activity relationship in pharmacology , *MACROLIDE antibiotics , *ORGANIC synthesis , *INDOLE alkaloids , *PROTEIN kinase C , *ANTINEOPLASTIC agents , *TARGETED drug delivery , *ENZYME activation - Abstract
Protein kinase C (PKC) isozymes are promising targets for anticancer therapy. Bryostatin-1 (bryo-1), a unique PKC activator with little tumor-promoting activity, is currently in clinical trials for the treatment of cancer. However, its limited availability from natural sources and its synthetic complexity have hampered studies of its mode of action and structural optimization as a therapeutic agent. The development of synthetically more accessible compounds with bryo-1-like activities is thus needed. Recently, we developed a simple and less lipophilic analogue of tumor-promoting aplysiatoxin (ATX) (aplog-1) as a promising lead for bryo-1-like anticancer drugs. Structure--activity studies suggested that local hydro - phobicity around the spiroketal moiety of aplog-1 is a crucial determinant of its antiproliferative activity. The hydrophobic analogue (12,12-dimethyl-aplog-1) displayed more potent antiproliferative activity. Moreover, it showed little tumor-promoting activity and even suppressed the tumor promotion by 12-O-tetradecanoylphorbol 13-acetate (TPA) in vivo and in vitro. Aplog-1 and bryo-1 bound selectively to novel PKC isozymes (δ, η, and ϑ) while tumor promoters bound to both conventional and novel PKC isozymes. These results suggest that the unique biological activities of aplog-1 and bryo-1 are ascribable in part to the ability to bind to PKCδ, but weak binding to conventional PKC isozymes might also be important. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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515. Cancer preventive agents 11. Novel analogs of dimethyl dicarboxylate biphenyl as potent cancer chemopreventive agents†.
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Hung, Hsin-Yi, Nakagawa-Goto, Kyoko, Tokuda, Harukuni, Iida, Akira, Suzuki, Nobutaka, Morris-Natschke, Susan L., and Lee, Kuo-Hsiung
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CANCER prevention , *ANTINEOPLASTIC agents , *CANCER chemoprevention , *DRUG design , *PHARMACEUTICAL chemistry , *CARCINOGENESIS , *SKIN tumors , *PROMOTERS (Genetics) - Abstract
Context: Dimethyl dicarboxylate biphenyl (DDB) is a clinically used hepatoprotectant and has also been found to have chemopreventive activity. Materials and methods: Sixteen novel analogs ( 5-20) were designed, synthesized, and evaluated for their cancer preventive activity. The 2,2′-bismethyl ester ( 5-18) and ether ( 19, 20) DDB analogs were synthesized by insertion of various linear alkyl, short fatty acid, polar, and aromatic groups. All synthesized analogs were evaluated in an in vitro short-term 12- O-tetradecanoylphorbol-13-acetate (TPA)-induced Epstein Barr virus early antigen (EBA-EA) activation assay. Three of the most potent compounds were also tested for inhibitory effects on skin tumor promotion in an in vivo two-stage mouse-skin carcinogenesis test using 7,12-dimethylbenz[ a]anthracene (DMBA) as an initiator and TPA as a promoter. Results: Compound 19 with bisprenyl ethers had the most significant cancer preventive activity (100% inhibition of activation at 1 × 103 mol ratio/TPA, 78.4%, 49.7%, and 10.9% inhibition at 5 × 102, 1 × 102, 1 × 10 mol ratio/TPA, respectively) in vitro. Compound 19 also exhibited a remarkable inhibitory effect on skin tumor promotion in the in vivo two-stage mouse-skin carcinogenesis test. Discussion and conclusions: Thus, DDB analog 19 could be a valuable candidate as a cancer preventive agent or as a lead for the development of new antitumor promoter drugs. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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516. Conjugates of 3α-methoxyserrat-14-en-21β-ol (PJ-1) and 3β-methoxyserrat-14-en-21β-ol (PJ-2) as cancer chemopreventive agents
- Author
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Tanaka, Reiko, Tsujii, Hiroko, Yamada, Takeshi, Kajimoto, Tetsuya, Tokuda, Harukuni, Arai, Takanari, Suzuki, Nobutaka, Hasegawa, Junya, Hamashima, Yoshio, and Node, Manabu
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CANCER chemoprevention , *EPSTEIN-Barr virus , *ANTIGENS , *PHENOLS , *GLYCINE , *ACETIC acid , *CARCINOGENESIS - Abstract
Abstract: 3α-Methoxyserrat-14-en-21β-ol (PJ-1) and 3β-methoxyserrat-14-en-21β-ol (PJ-2) were conjugated with well-known phenolic compounds, narigenin, hesperetin, genistein, and daidzein (1–8). Other conjugates of PJ-2–3,5-dihydroxy-4-methoxybenzoic acid (9), PJ-2–pyrogallol (10), and derivatives of PJ-1, PJ-2–3,3-dimethyl-succinates (11, 12), PJ-1, PJ-2–succinates (13, 14), PJ-2–glycine (15), PJ-2–piperidine acetic acid (16), and PJ-1 epoxy–3,3-dimethyl-succinate (17) were tested for their inhibitory effects on Epstein–Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). The inhibitory effects of 11 (IC50 = 251), 12 (IC50 = 248), and 17 (IC50 = 230 mol ratio/32 pmol/TPA), were 2-fold stronger than those of the other compounds such as oleanolic acid (IC50 = 449). Compounds 10, 11, and 17 inhibited mouse skin tumor promotion in an in vivo two-stage carcinogenesis model. The in vivo two-stage mouse-skin carcinogenesis test employed 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. [Copyright &y& Elsevier]
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- 2011
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517. Part I: Synthesis, cancer chemopreventive activity and molecular docking study of novel quinoxaline derivatives
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Galal, Shadia A., Abdelsamie, Ahmed S., Tokuda, Harukuni, Suzuki, Nobutaka, Lida, Akira, ElHefnawi, Mahmoud M., Ramadan, Raghda A., Atta, Mona H.E., and El Diwani, Hoda I.
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QUINOXALINES , *PHENYLENEDIAMINES , *BENZIMIDAZOLES , *EPSTEIN-Barr virus , *CARCINOGENESIS , *PROTEIN kinases , *CELL-mediated cytotoxicity - Abstract
Abstract: The reaction of o-phenylene diamine and ethyl oxamate is reinvestigated and led to 3-aminoquinoxalin-2(1H)-one rather than benzimidazole-2-carboxamide as was previously reported. The structure of the obtained quinoxaline has been confirmed by X-ray. The anti-tumor activity of synthesized quinoxalines 1–21 has been evaluated by studying their possible inhibitory effects on Epstein–Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). Among the studied compounds 1–21, compounds 12, 8, 13, 18, 17 and 19, respectively, demonstrated strong inhibitory effects on the EBV-EA activation without showing any cytotoxicity and their effects being stronger than that of a representative control, oleanolic acid. Furthermore, compound 12 exhibited a remarkable inhibitory effect on skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test using 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. The result of the present investigation indicated that compound 12 might be valuable as a potent cancer chemopreventive agent. Moreover, the molecular docking into PTK (PDB: 1t46) has been done for lead optimization of the aforementioned compounds as potential PTK inhibitors. [Copyright &y& Elsevier]
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- 2011
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518. Apoptosis signal-regulating kinase 1 is crucial for oxidative stress-induced but not for osmotic stress-induced hepatocyte cell death
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Taki, Kenji, Shimozono, Rieko, Kusano, Hajime, Suzuki, Nobutaka, Shinjo, Katsuhiro, and Eda, Hiroyuki
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CELL death , *MITOGEN-activated protein kinases , *OXIDATIVE stress , *LIVER cells , *WESTERN immunoblotting , *REACTIVE oxygen species , *LABORATORY mice - Abstract
Abstract: Aims: In this study, we investigated the involvement of apoptosis signal-regulating kinase 1 (ASK1) in oxidative stress and osmotic stress-induced hepatocyte death. Main methods: Activation of ASK1–JNK/p38 cascade and resulting cell death induced by oxidative and osmotic stress was investigated by Western immunoblot analysis and cell toxicity assay using human hepatoma cell lines, Huh7 expressing high level of ASK1 and HepG2 cells expressing low level of ASK1. Gene knock-down of ASK1 using shRNA against ASK1 was conducted using mouse hepatocyte cell line, AML12. Key findings: Activation of ASK1–JNK/p38 cascade and cell death in Huh7 expressing high level of ASK1 was markedly induced by the oxidative stress. HepG2 expressing low level of ASK1 was resistant to oxidative stress while cell death induced by osmotic stress was comparable between Huh7 and HepG2 cells. Although the phosphorylation of ASK1 was not observed by osmotic stress, the phosphorylation of p38 and JNK and resulting cell death was induced in both cell lines. The phosphorylation of ASK1 and p38/JNK in the mouse primary hepatocyte were also increased by oxidative stress. Knock-down of ASK1 mRNA in AML12 in vitro significantly reduced oxidative stress-induced cell death, however, knock-down of ASK1 in cells did not affect the osmotic stress-induced cell death. Significance: This study revealed that ASK1 regulates oxidative stress- but not osmotic stress-induced hepatocyte death, suggesting ASK1 plays a critical role in oxidative-stress induced hepatocyte death. These results raise the possibility that an ASK1 may be a promising therapeutic target for liver diseases caused by oxidative stress. [Copyright &y& Elsevier]
- Published
- 2008
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519. Antioxidative Activities and Angiotensin I-Converting Enzyme Inhibition of Extracts Prepared from Chum Salmon (Oncorhynchus Keta) Cartilage and Skin
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Nagai, Takeshi, Nagashima, Toshio, Abe, Atushi, and Suzuki, Nobutaka
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CHUM salmon , *CARTILAGE , *SKIN , *ACE inhibitors , *ANTIOXIDANTS , *SALMON , *FOOD science , *COOKING - Abstract
The extracts from cartilage and skin of chum salmon were prepared using a pressure cooker. As a result, protein and collagen contents in extracts from cartilage and skin was higher than those only in cartilage. The inhibition activity of linoleic acid oxidation was high in extract from cartilage. The scavenging activity of cartilage extract was higher than those of cartilage and skin against all reactive oxygen species, such as superoxide anion, hydroxyl, and DPPH radicals. On the other hand, angiotensin I-converting enzyme inhibitory activity of cartilage extract was about seven times as high as that of cartilage and skin extract. The present studies indicate that the extracts, particularly from cartilage, have angiotensin I-converting enzyme inhibitory activity that functions to depress hypertension, and antioxidant activity, which acts to prevent of life-style related diseases such as cancer, cardiovascular diseases, and diabetes. The data should be useful for developing a novel type of functional seasoning. [ABSTRACT FROM AUTHOR]
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- 2006
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520. Characterization of honey from different floral sources. Its functional properties and effects of honey species on storage of meat
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Nagai, Takeshi, Inoue, Reiji, Kanamori, Norio, Suzuki, Nobutaka, and Nagashima, Toshio
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NECTAR , *REACTIVE oxygen species , *PEROXIDATION , *VITAMIN C - Abstract
Abstract: The antioxidative effects of honey species and their related products were evaluated using a lipid peroxidation model system. The antioxidant activities of honey species gradually decreased with passage of time. Buckwheat honey was as effective as 1mM α-tocopherol. Superoxide-scavenging activities of propolis and royal jelly were strongest among the honey species tested. 1,1-Diphenyl-2-picrylhydrazyl radical scavenging ability of sample species were lower than those of 1mM ascorbic acid and α-tocopherol. Hydroxyl radical scavenging activity was very high in all honeys (over 77% inhibition). From the results of the bacterial test on storage of meat and muscle, each honey exhibited the inhibition of bacterial growth. In particular, propolis and royal jelly exhibited the strongest inhibitory effects against bacterial growth. This suggests that honey species from different floral sources possess strong antioxidative and antibacterial activities and are scavengers of active oxygen species. [Copyright &y& Elsevier]
- Published
- 2006
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521. Role of a transductional -- transcriptional processor complex involving MyD88 and IRF-7 in Toll-like receptor signaling.
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Honda, Kenya, Yanai, Hideyuki, Mizutani, Tatsuaki, Negishi, Hideo, Shimada, Naoya, Suzuki, Nobutaka, Ohba, Yusuke, Takaoka, Akinori, Wen-Chen Yeh, and Taniguchi, Tadatsugu
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TRANSCRIPTION factors , *CYTOPLASM , *GENES , *GENETIC transcription , *PROTEIN kinases - Abstract
Toll-like receptor (TLR) activation is central to immunity, wherein the activation of the TLR9 subfamily members TLR9 and TLR7 results in the robust induction of type I IFNs (IFN-α/β) by means of the MyD88 adaptor protein. However, it remains unknown how the TLR signal "input" can be processed through MyD88 to "out- put" the induction of the lFN genes. Here, we demonstrate that the transcription factor IRF-7 interacts with MyD88 to form a complex in the cytoplasm. We provide evidence that this complex also involves IRAK4 and TRAF6 and provides the foundation for the TLR9-dependent activation of the IFN genes. The complex defined in this study represents an example of how the coupling of the signaling adaptor and effector kinase molecules together with the transcription factor regulate the processing of an extracellular signal to evoke its versatile downstream transcriptional events in a cell. Thus, we propose that this molecular complex may function as a cytoplasmic transductional-transcriptional processor. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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522. Effects of the traditional Japanese medicine Unkei-to on the corticotropin-releasing factor–induced increase in locomotor activity
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Terawaki, Kiyoshi, Koike, Koji, Yuzurihara, Mitsutoshi, Kase, Yoshio, Takeda, Shuichi, Aburada, Masaki, Murakami, Kouichi, Ohno, Satoshi, Suzuki, Nobutaka, and Inoue, Masaki
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HERBAL medicine , *LABORATORY rats , *HERBAL contraceptives , *MEDICINE - Abstract
The effect of Unkei-to, a traditional Japanese herbal medicine and strong in vitro releaser of cytokine-induced neutrophil chemoattractant (CINC), on the increase in locomotor activity induced by intracerebroventricular (icv) injection of corticotropin-releasing factor (CRF) in male rats in a familiar environment was investigated. Oral administration of Unkei-to (100 mg/kg) for 1 week significantly attenuated the CRF-induced increase in locomotor activity. Unkei-to also reduced the CRF-induced accumulation of hypothalamic CINC, which has a functional antagonistic action on the response to CRF; the reduction may reflect an increased release of CINC. These results suggest that Unkei-to has an alleviative effect on the action induced by brain CRF and the mechanism of this effect may partly involve CINC. [Copyright &y& Elsevier]
- Published
- 2004
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- View/download PDF
523. The MAGUK Family Protein CARD11 Is Essential for Lymphocyte Activation
- Author
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Hara, Hiromitsu, Wada, Teiji, Bakal, Chris, Kozieradzki, Ivona, Suzuki, Shinobu, Suzuki, Nobutaka, Nghiem, Mai, Griffiths, Emily K., Krawczyk, Connie, Bauer, Birgit, D'Acquisto, Fulvio, Ghosh, Sankar, Yeh, Wen-Chen, Baier, Gottfried, Rottapel, Robert, and Penninger, Josef M.
- Subjects
- *
ADRENERGIC receptors , *SYNAPSES - Abstract
Members of the MAGUK family proteins cluster receptors and intracellular signaling molecules at the neuronal synapse. We report that genetic inactivation of the MAGUK family protein CARD11/Carma1/Bimp3 results in a complete block in T and B cell immunity. CARD11 is essential for antigen receptor- and PKC-mediated proliferation and cytokine production in T and B cells due to a selective defect in JNK and NFκB activation. Moreover, B cell proliferation and JNK activation were impaired upon stimulation of TLR4 with lipopolysaccharide, indicating that CARD11 is involved in both the innate and adaptive immune systems. Our results show that the same family of molecules are critical regulators of neuronal synapses and immune receptor signaling. [Copyright &y& Elsevier]
- Published
- 2003
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- View/download PDF
524. Role of SODD in Regulation of Tumor Necrosis Factor Reponses.
- Author
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Takada, Hidetoshi, Nien-Jung Chen, Mirtsos, Christine, Suzuki, Shinobu, Suzuki, Nobutaka, Wakeham, Andrew, Mak, Tak W., and Wen-Chen Yeh
- Subjects
- *
TUMOR necrosis factors , *PROTEINS , *CYTOPLASM - Abstract
Signaling from tumor necrosis factor receptor type 1 (TNFR1) can elicit potent inflammatory and cytotoxic responses that need to be properly regulated. It was suggested that the silencer of death domains (SODD) protein constitutively associates intracellularly with TNFR1 and inhibits the recruitment of cytoplasmic signaling proteins to TNFR1 to prevent spontaneous aggregation of the cytoplasmic death domains of TNFR1 molecules that are juxtaposed in the absence of ligand stimulation. In this study, we demonstrate that mice lacking SODD produce larger amounts of cytokines in response to in vivo TNF challenge. SODD-deficient macrophages and embryonic fibroblasts also show altered responses to TNF. TNF-induced activation of NF-κB is accelerated in SODD-deficient cells, but TNF-induced c-Jun N-terminal kinase activity is slightly repressed. Interestingly, the apoptotic arm of TNF signaling is not hyperresponsive in the SODD-deficient cells. Together, these results suggest that SODD is critical for the regulation of TNF signaling. [ABSTRACT FROM AUTHOR]
- Published
- 2003
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- View/download PDF
525. Preparation and antioxidant properties of water extract of propolis
- Author
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Nagai, Takeshi, Inoue, Reiji, Inoue, Hachiro, and Suzuki, Nobutaka
- Subjects
- *
PROPOLIS , *ANTIOXIDANTS - Abstract
A water extract was prepared from fresh propolis from Brazil. Antioxidant activity was measured using a lipid peroxidation model system. The activity was very strong and, at 1 and 5 mg/ml, higher than that of 5 mM ascorbic acid. The scavenging activity against superoxide anion radical of water extract of propolis was high, and the extracts, at 50 and 100 mg/ml, completely inhibited the production of superoxide. The extracts, at 50 and 100 mg/ml, completely inhibited the hydroxyl radical. This suggests that the water extract of propolis has potential as a pharmaceutical for patients with various diseases such as cancer, cardiovascular diseases, and diabetes. [Copyright &y& Elsevier]
- Published
- 2003
- Full Text
- View/download PDF
526. Accumulation of hydroxy lipids in live fish infected with fish diseases
- Author
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Tanaka, Ryusuke, Higo, Yoshikazu, Shibata, Toshiyuki, Suzuki, Nobutaka, Hatate, Hideo, Nagayama, Koki, and Nakamura, Takashi
- Subjects
- *
FISH diseases , *LIPIDS - Abstract
Lipid hydroperoxide (LPO) and hydroxy lipid levels of diseased fishes were investigated. Although significant differences in LPO levels were not always observed between normal and diseased fish, hydroxy lipid levels in muscle and liver were significantly higher in diseased fish than in uninfected normal fish cultured with the same feed in the same cage or in wild normal fish. Hydroxy triglyceride levels of diseased yellowtails with streptococcal infection were significantly elevated in ordinary and dark muscle, and especially in the liver; 1072±78 in diseased fish compared to 632±45 (nmol/g tissue) in normal fish cultured with the same feed. In this case, the polyunsaturated fatty acid contents of the diseased fish were decreased. This was notable, especially with respect to the decrease of docosahexaenoic acid. These trends, namely, increased accumulation of hydroxy lipids in the liver of diseased fish and decreased levels of polyunsaturated fatty acids, were observed in sweetfish with ulcer disease, globefish with Heterobothrium okamotoi infection and/or emaciation disease, red sea bream infected with edwardsiellosis and/or Vibrio anguillarum, yellowtail with jaundiced disease, and carp with cold water disease. [Copyright &y& Elsevier]
- Published
- 2002
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- View/download PDF
527. Scavenging capacities of pollen extracts from cistus ladaniferus on autoxidation, superoxide radicals, hydroxyl radicals, and DPPH radicals.
- Author
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Nagai, Takeshi, Inoue, Reiji, Inoue, Hachiro, and Suzuki, Nobutaka
- Subjects
- *
POLLEN , *ANTIOXIDANTS , *REACTIVE oxygen species - Abstract
The antioxidative abilities of pollen extracts were evaluated using lipid peroxidation model system. Ethanol-soluble fraction (ESF) was most active followed by hot-water fraction (HWF). These abilities of pollen extracts were higher than that of 5 mM ascorbic acid and were similar to that of 1 mM α-tocopherol. Superoxide-scavenging capacities were decreased in the order water-soluble fraction > HWF > ESF. ESF showed the highest hydroxyl radical scavenging ability among these samples. The pollen extracts showed DPPH radical scavenging ability. Particularly the ability of ESF gradually increased with passage of the time (about 80% to 10 min). It suggests that the extracts of the pollen are good scavengers of active oxygen species. This property of the pollen seems to be important in prevention of various diseases such as cancer, cardiovascular diseases, and diabetes. [Copyright &y& Elsevier]
- Published
- 2002
- Full Text
- View/download PDF
528. Collagen of octopus Callistoctopus arakawai arm.
- Author
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Nagai, Takeshi, Nagamori, Keiko, Yamashita, Eiji, and Suzuki, Nobutaka
- Subjects
- *
COLLAGEN , *OCTOPUSES , *FOOD composition , *SEAFOOD - Abstract
In an investigation into making more effective use of underutilized fisheries resources, collagen was prepared from Callistoctopus arakawai arm. The arm was only slightly solubilized in acetic acid but on digestion with 10% pepsin (w/v), pepsin-solubilized collagen (PSC) was successfully produced. The PSC obtained was a pinkish fibre. The yields of acid-solubilized collagen (ASC) and PSC were about 10.4 and 62.9%, respectively. The PSC has a chain composition of α1α2α3 heterotrimer, different from Octopus vulgaris skin. The denaturation temperature of this collagen was lower than porcine collagen. This report indicates that C. arakawai has potential for supplementing the skin of land vertebrates as a source of collagen. [ABSTRACT FROM AUTHOR]
- Published
- 2002
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- View/download PDF
529. 4-Ketozeinoxanthin, a novel carotenoid produced in Escherichia coli through metabolic engineering using carotenogenic genes of bacterium and liverwort.
- Author
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Maoka, Takashi, Takemura, Miho, Tokuda, Harukuni, Suzuki, Nobutaka, and Misawa, Norihiko
- Subjects
- *
CAROTENOIDS , *METABOLISM , *MARINE ecology , *LYCOPENE , *HYDROXYLASES , *ESCHERICHIA coli - Abstract
In order to produce a novel keto-carotenoid in Escherichia coli , we introduced the marine bacterial carotenoid ketolase gene ( crtW ) into pathway-engineered E. coli producing carotenoids of plant origin, which carried the lycopene biosynthesis genes ( crtE , crtB , and crtI ) from soil bacterium Pantoea ananatis and the liverwort Marchantia polymorpha genes that encode lycopene β-cyclase ( MpLCYb ), lycopene ε-cyclase ( MpLCYe ), and β-carotenoid hydroxylase ( MpBHY ). A novel keto-carotenoid ( 1 ) was produced by these carotenoid biosynthesis genes in E. coli along with α-echinenone, adonirubin, and adonixanthin. The structure of 1 was determined as (3 S ,6′ R )-3-hydroxy-β,ε-caroten-4-one based on Uv–vis, MS, 1 H NMR, and CD spectral data. This compound was named 4-ketozeinoxanthin and showed anti-tumor-promoting activity. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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- View/download PDF
530. Identification and Biological Activities of Bryostatins from Japanese Bryozoan.
- Author
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Ueno, Sayo, Yanagita, Ryo C., Murakami, Kazuma, Murakami, Akira, Tokuda, Harukuni, Suzuki, Nobutaka, Fujiwara, Takeshi, and Irie, Kazuhiro
- Subjects
- *
BRYOZOA , *EPSTEIN-Barr virus , *ANTIGENS , *PROTEIN kinase C , *ESTERS , *ANTINEOPLASTIC agents , *LACTONES - Abstract
The article discusses identification and determination of biological activities of macrolide lactones bryostatins that was isolated from bryozoan moss animals species. The structural analysis of bryostatins reveals that ester group at 20th position of carbon is not necessary for binding and activation of Protein Kinase C. The anti tumor properties of bryostatins in induction tests with the epstein barr virus early antigen is also included.
- Published
- 2012
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531. Chemopreventive activities of etodolac and oxyphenbutazone against mouse skin carcinogenesis
- Author
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Kapadia, Govind J., Azuine, Magnus A., Shigeta, Yuuko, Suzuki, Nobutaka, and Tokuda, Harukuni
- Subjects
- *
SKIN cancer prevention , *CHEMOPREVENTION , *CARCINOGENESIS , *LABORATORY mice , *NONSTEROIDAL anti-inflammatory agents , *ANTHRACENE , *EPSTEIN-Barr virus , *ANTIGENS , *OXYPHENBUTAZONE - Abstract
Abstract: Previous cancer chemoprevention studies have demonstrated that the non-steroidal anti-inflammatory drugs (NSAIDs) can be effective in suppressing the development of various human malignancies. Recently we identified the possible anti-tumor promoting potentials of 14 new NSAIDs in the Epstein–Barr virus early antigen activation assay induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). In this study we report the inhibition of 7,12-dimethylbenz (a) anthracene (DMBA) induced two-stage mouse skin carcinogenesis by etodolac (ETD), one of the most potent NSAIDs identified in our in vitro cancer chemopreventive screening of this group of drugs. Topical administration of ETD at a very low dose of 85nmol showed a significant decrease in both tumor incidence and burden. This effect is also accompanied by a delay in the tumor latency period. Since ETD showed potent chemopreventive activity in both in vitro and in vivo studies, it warrants prompt consideration for trial in humans as a potential cancer chemopreventive agent. We also investigated oxyphenbutazone (OPB) another commonly used NSAID for its cancer chemopreventive effect on peroxynitrite (PN) induced-TPA promoted skin tumors in the mouse. Following tumor initiation with 390nmol of PN, the skin tumor promotion with 1.7nmol of TPA was significantly inhibited by oral administration of 0.0025% OPB. The results demonstrate that OPB is a potent cancer chemopreventive agent in the highly sensitive in vivo mouse test model we used. [Copyright &y& Elsevier]
- Published
- 2010
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- View/download PDF
532. ChemInform Abstract: Synthesis of Antineoplastic Analogues of Aplysiatoxin with Various Side Chain Structures.
- Author
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Shu, Yuki, Yanagita, Ryo C., Tokuda, Harukuni, Suzuki, Nobutaka, and Irie, Kazuhiro
- Abstract
A synthetic route to simplified analogues of aplysiatoxin (Ia-c) is developed. [ABSTRACT FROM AUTHOR]
- Published
- 2013
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- View/download PDF
533. ChemInform Abstract: Synthesis and Structure-Activity Studies of Simplified Analogues of Aplysiatoxin with Antiproliferative Activity Like Bryostatin-1.
- Author
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Irie, Kazuhiro, Kikumori, Masayuki, Kamachi, Hiroaki, Tanaka, Keisuke, Murakami, Akira, Yanagita, Ryo C., Tokuda, Harukuni, Suzuki, Nobutaka, Nagai, Hiroshi, Suenaga, Kiyotake, and et al., et al.
- Abstract
Review: 57 refs. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
534. Characterization of Collagen from Sakhalin Taimen Skin as Useful Biomass.
- Author
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Nagai T, Saito M, Tanoue Y, Kai N, and Suzuki N
- Abstract
Research Background: Animal collagen has been widely utilized in foods, cosmetics and biomedical fields. The non-edible portion, such as fish skin and bones, are obtained during cooking. Most of them are currently discarded as wastes, although the nutritional value of the skin and bones is high. The non-edible portion needs to be reused in order to reduce environmental impact, as it is one of the sources of environmental pollution., Experimental Approach: Collagen was prepared by cold acetone treatment from Sakhalin taimen skin as a waste produced during cooking. Next, the colour, SDS-polyacrylamide gel electrophoresis, ultraviolet absorption, subunit composition, amino acid composition, denaturation temperature and attenuated total reflectance-Fourier transform infrared spectroscopy analyses were conducted to explore the properties of the collagen. Lastly, we attempted to improve the functional properties of the collagen for future applications using chemical modification technique (succinylation)., Results and Conclusions: Cold acetone treatment easily removed the fats and pigments from the skin. The odourless and pure white collagen was obtained with high yield. The α3 chain did not exist in the collagen. Sakhalin taimen skin collagen had rich α-helix and low β-sheet structures. Succinylation caused the secondary structural changes of the collagen molecule. Moreover, it made it possible not only to increase the viscosity of the collagen solution but also to improve the solubility of the collagen under the physiological conditions around pH=6., Novelty and Scientific Contribution: This finding is the first report on the absence of the α3 chain from salmonid fish skin collagens. The succinylated collagen from Sakhalin taimen skins as useful biomass has potential to utilize in foods, cosmetics and related industries., Competing Interests: CONFLICT OF INTEREST The authors declare that they have no conflict of interest.
- Published
- 2020
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- View/download PDF
535. Safety Assessment of Bangle ( Zingiber purpureum Rosc.) Rhizome Extract: Acute and Chronic Studies in Rats and Clinical Studies in Human.
- Author
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Kato E, Kubo M, Okamoto Y, Matsunaga Y, Kyo H, Suzuki N, Uebaba K, and Fukuyama Y
- Abstract
Bangle ( Zingiber purpureum Rosc.) rhizome extract (BRE) contains phenylbutenoid dimers (banglenes), which exert neurotrophic effects and possess the potential capability to regenerate hippocampal neurons in mice. The acute and chronic oral toxicities of BRE powder were evaluated in Sprague-Dawley rats. A dose of BRE powder was estimated to be higher than 2000 mg/kg containing BRE 534 mg/kg as minimum lethal dose in a single-dose oral toxicity study. The no-observed-adverse-effect-level for the BRE powder was 1000 mg/kg/day (BRE 267 mg/kg) in the 90 day oral toxicity study. Four week clinical studies of BRE tablets in humans suggested that the ingestion of BRE tablets within 850 mg/man/day (BRE 227 mg/man/day) was safe for at least 1 month and in a usual manner. The C
max , tmax , and AUC of cis - and trans -( E )-3-(3,4-dimethoxyphenyl)-4-[( E )-3,4-dimethoxystyryl]cyclohex-1-enes ( c - and t -banglenes) were calculated after the ingestion of BRE tablets (BRE 227 mg) and were 17.73 and 22.61 ng/mL, 1.8 and 1.8 h, and 71.47 and 95.53 ng/mL/h, respectively., Competing Interests: The authors declare no competing financial interest.- Published
- 2018
- Full Text
- View/download PDF
536. Phenylethylchromones with In Vitro Antitumor Promoting Activity from Aquilaria filaria.
- Author
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Suzuki A, Miyake K, Saito Y, Rasyid FA, Tokuda H, Takeuchi M, Suzuki N, Ichiishi E, Fujie T, Goto M, Sasaki Y, and Nakagawa-Goto K
- Subjects
- Antigens, Viral metabolism, Antineoplastic Agents isolation & purification, Antineoplastic Agents, Phytogenic chemistry, Antineoplastic Agents, Phytogenic isolation & purification, Antineoplastic Agents, Phytogenic pharmacology, Cell Line, Tumor, Chromones isolation & purification, Drug Resistance, Neoplasm, Flavonoids chemistry, Flavonoids pharmacology, Humans, Inhibitory Concentration 50, Plant Extracts chemistry, Plant Extracts pharmacology, Tetradecanoylphorbol Acetate analogs & derivatives, Tetradecanoylphorbol Acetate pharmacology, Antineoplastic Agents chemistry, Antineoplastic Agents pharmacology, Chromones chemistry, Chromones pharmacology, Thymelaeaceae chemistry
- Abstract
A new chromone, 2-(2-hydroxy-2-phenylethyl)chromone ( 1 ), was isolated together with ten known phenylethyl chromones from MeOH extracts of agarwood ( Aquilaria filaria ). The selected compounds were evaluated in an antiproliferative assay against five human tumor cell lines, including a multidrug-resistant cell line. They were also tested for antitumor promoting activity, as mediated by 12- O -tetradecanoylphorbol-13-acetate-induced activation of the Epstein-Barr virus early antigen in Raji cells. Among all compounds, 4',7-dimethyoxy-6-hydroxychromone ( 2 ) displayed broad spectrum antiproliferative activity against all tumor cell lines tested with IC
50 values of 25-38 µM, while 8 was selectively inhibitory against multidrug-resistant cells. All tested compounds suppressed tumor promotion at noncytotoxic concentrations. 4',6-Dihydroxyphenylethylchromone ( 7 ) exhibited the most potent effect with an IC50 value of 319 mol ratio relative to 12- O -tetradecanoylphorbol-13-acetate. This study is the first to report the antitumor promoting activity of 2-(2-phenylethyl)chromone derivatives, as well as the selective antiproliferative activity of 8 against a multidrug-resistant tumor cell line., (Georg Thieme Verlag KG Stuttgart · New York.)- Published
- 2017
- Full Text
- View/download PDF
537. Total Synthesis and in Vitro Anti-Tumor-Promoting Activities of Racemic Acetophenone Monomers from Acronychia trifoliolata.
- Author
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Morita C, Kobayashi Y, Saito Y, Miyake K, Tokuda H, Suzuki N, Ichiishi E, Lee KH, and Nakagawa-Goto K
- Subjects
- Acetophenones chemistry, Antigens, Viral drug effects, Carcinogens pharmacology, Herpesvirus 4, Human drug effects, Humans, Molecular Structure, Neoplasms, Stereoisomerism, Structure-Activity Relationship, Tetradecanoylphorbol Acetate pharmacology, Acetophenones chemical synthesis, Acetophenones pharmacology, Rutaceae chemistry
- Abstract
Six acetophenone derivatives, acronyculatins I (1), J (2), K (3), L (4), N (5), and O (6), were recently isolated from Acronychia trifoliolata, and the structure of the known acronyculatin B (7) was revised. Because of the limited quantities of isolated products as well as their structure similarity, racemic acronyculatins I-L, N, O, and B (1-7) were synthesized to confirm their structures and to obtain sufficient material for biological evaluation. Trihydroxyacetophenone was converted to the target compounds by various sequences of hydroxy group protection, allylation or prenylation, and epoxidation followed by cyclization. C-Prenylations were carried out by direct addition of a prenyl group or through 1,3- or 3,3-sigmatropic rearrangement. The synthesized racemic compounds were evaluated in an anti-tumor-promoting assay using the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate in Raji cells. All tested compounds significantly inhibited EBV-EA activation. Especially, racemic acronyculatin I (1) displayed the most potent inhibitory effects, with an IC
50 value of 7.3 μM.- Published
- 2016
- Full Text
- View/download PDF
538. Anti-inflammatory and cytoprotective effects of a squalene synthase inhibitor, TAK-475 active metabolite-I, in immune cells simulating mevalonate kinase deficiency (MKD)-like condition.
- Author
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Suzuki N, Ito T, Matsui H, and Takizawa M
- Abstract
TAK-475 (lapaquistat acetate) and its active metabolite-I (TAK-475 M-I) inhibit squalene synthase, which catalyzes the conversion of farnesyl diphosphate (FPP) to squalene. FPP is a substrate for synthesis of other mevalonate-derived isoprenoids (MDIs) such as farnesol (FOH), geranlygeranyl diphosphate (GGPP), and geranylgeraniol. In patients with MKD, a rare autosomal recessive disorder, defective activity of mevalonate kinase leads to a shortage of MDIs. MDIs especially GGPP are required for prenylation of proteins, which is a posttranslation modification necessary for proper functioning of proteins like small guanosine triphosphatases. Malfunction of prenylation of proteins results in upregulation of the inflammatory cascade, leading to increased production of proinflammatory cytokines like interleukin-1β (IL-1β), eventually leading to episodic febrile attacks. In vitro, TAK-475 M-I incubation in a concentration dependent manner increased levels of FPP, GGPP, and FOH in human monocytic THP-1 cells. In subsequent experiments, THP-1 cells or human peripheral blood mononuclear cells (PBMCs) were incubated with simvastatin, which inhibits hydroxymethylglutaryl-coenzyme A reductase and thereby decreases levels of the precursors of MDIs, leading to the depletion of MDIs as expected in MKD patients. Increased levels of GGPP and FPP attenuated lipopolysaccharide (LPS)-induced IL-1β production in THP-1 cells and human PBMCs in statin-treated conditions. The MDIs also significantly reduced the damaged cell ratio in this active MKD-like condition. Moreover, TAK-475 M-I directly inhibited LPS-induced IL-1β production from statin-treated THP-1 cells. These results show anti-inflammatory and cytoprotective effects of MDIs via TAK-475 M-I treatment in statin-treated immune cells, suggesting that possible therapeutic effects of TAK-475 treatment in MKD patients.
- Published
- 2016
- Full Text
- View/download PDF
539. Characterization of collagen from emu (Dromaius novaehollandiae) skins.
- Author
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Nagai T, Tanoue Y, Kai N, and Suzuki N
- Abstract
Collagen from emu skins as a by-product was prepared. The skins were hardly solubilized in acetic acid, however were successfully solubilized on digestion with 10 % pepsin (w/w) for 4 days. The yield of pepsin-solubilized collagen (PSC) was about 27.3 %, on a raw weight basis. By SDS-PAGE and CM-Toyopearl 650 M column chromatography, the presence of a fourth subunit that was previously designated α4 was confirmed. The denaturation temperature of the PSC was 31.5 °C, about 6-7 °C lower than that from the porcine skins. ATR-FTIR analysis indicated that the helical arrangements of the PSC from emu skins existed and its structures of PSC were changed slightly due to the loss of N- and C-terminus domains in similar to that from the porcine skins. That is, the PSC from emu skins did not possess telopeptide chains as major portion of antigenic sites in collagen. The present study indicates that a large quantity of emu skins as by-products have potential as a good alternative source of high-quality collagen for industrial purposes in the foods, cosmetics, and pharmaceutical and biomedical fields.
- Published
- 2015
- Full Text
- View/download PDF
540. Synthesis and biological activities of the amide derivative of aplog-1, a simplified analog of aplysiatoxin with anti-proliferative and cytotoxic activities.
- Author
-
Hanaki Y, Yanagita RC, Sugahara T, Aida M, Tokuda H, Suzuki N, and Irie K
- Subjects
- Antineoplastic Agents chemistry, Cell Line, Tumor, Cell Proliferation drug effects, Chemistry Techniques, Synthetic, Humans, Isoenzymes antagonists & inhibitors, Lyngbya Toxins chemistry, Models, Molecular, Molecular Conformation, Protein Kinase C-delta antagonists & inhibitors, Structure-Activity Relationship, Amides chemistry, Antineoplastic Agents chemical synthesis, Antineoplastic Agents pharmacology, Lyngbya Toxins chemical synthesis, Lyngbya Toxins pharmacology
- Abstract
Aplog-1 is a simplified analog of the tumor-promoting aplysiatoxin with anti-proliferative and cytotoxic activities against several cancer cell lines. Our recent findings have suggested that protein kinase Cδ (PKCδ) could be one of the target proteins of aplog-1. In this study, we synthesized amide-aplog-1 (3), in which the C-1 ester group was replaced with an amide group, to improve chemical stability in vivo. Unfortunately, 3 exhibited seventy-fold weaker binding affinity to the C1B domain of PKCδ than that of aplog-1, and negligible anti-proliferative and cytotoxic activities even at 10(-4) M. A conformational analysis and density functional theory calculations indicated that the stable conformation of 3 differed from that of aplog-1. Since 27-methyl and 27-methoxy derivatives (1, 2) without the ability to bind to PKC isozymes exhibited marked anti-proliferative and cytotoxic activities at 10(-4) M, 3 may be an inactive control to identify the target proteins of aplogs.
- Published
- 2015
- Full Text
- View/download PDF
541. Functional properties of autolysate and enzymatic hydrolysates from yam tsukuneimo (Dioscorea opposita Thunb.) tuber mucilage tororo: antioxidative activity and antihypertensive activity.
- Author
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Nagai T, Suzuki N, Kai N, and Tanoue Y
- Abstract
Yam tsukuneimo tuber mucilage tororo hydrolysates were prepared by autolysis and three different peptic enzymes. Except for pepsin hydrolysate, tororo was perfectly digested. Each hydrolysate for 100 mg/ml significantly prolonged the induction period of auto-oxidation of linoleic acid, which was similar to 5 mM ascorbic acid. These hydrolysates also possessed high scavenging activities such as superoxide anion radicals, hydroxyl radicals, and DPPH radicals. Moreover, high antihypertensive activities were detected in these hydrolysates except for autolysate, which were similar to various fermented foods such as miso, natto, sake, cheese, and so on. Present findings suggest that yam tsukuneimo tuber mucilage tororo may be useful for preventing diseases associated with reactive oxygen species and blood pressure in the body system and it can fully absorb the useful components from it to digest using the gastrointestinal enzymes.
- Published
- 2014
- Full Text
- View/download PDF
542. A novel mouse model for Down syndrome that harbor a single copy of human artificial chromosome (HAC) carrying a limited number of genes from human chromosome 21.
- Author
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Miyamoto K, Suzuki N, Sakai K, Asakawa S, Okazaki T, Kudoh J, Ikeno M, and Shimizu N
- Subjects
- Animals, Crosses, Genetic, Embryonic Stem Cells metabolism, Gene Dosage genetics, Gene Expression Profiling, Humans, In Situ Hybridization, Fluorescence, Mice, Reverse Transcriptase Polymerase Chain Reaction, Transgenes genetics, Chromosomes, Artificial, Human genetics, Chromosomes, Human, Pair 21 genetics, Disease Models, Animal, Down Syndrome genetics
- Abstract
Down syndrome (DS), also known as Trisomy 21, is the most common chromosome aneuploidy in live-born children and displays a complicated symptom. To date, several kinds of mouse models have been generated to understand the molecular pathology of DS, yet the gene dosage effects and gene(s)-phenotype(s) correlation are not well understood. In this study, we established a novel method to generate a partial trisomy mice using the mouse ES cells that harbor a single copy of human artificial chromosome (HAC), into which a small human DNA segment containing human chromosome 21 genes cloned in a bacterial artificial chromosome (BAC) was recombined. The produced mice were found to maintain the HAC carrying human genes as a mini-chromosome, hence termed as a Trans-Mini-Chromosomal (TMC) mouse, and HAC was transmitted for more than twenty generations independent from endogenous mouse chromosomes. The three human transgenes including cystathionine β-synthase, U2 auxiliary factor and crystalline alpha A were expressed in several mouse tissues with various expression levels relative to mouse endogenous genes. The novel system is applicable to any of human and/or mouse BAC clones. Thus, the TMC mouse carrying a HAC with a limited number of genes would provide a novel tool for studying gene dosage effects involved in the DS molecular pathogenesis and the gene(s)-phenotype(s) correlation.
- Published
- 2014
- Full Text
- View/download PDF
543. Chemoprevention of skin cancer: effect of Lawsonia inermis L. (Henna) leaf powder and its pigment artifact, lawsone in the Epstein- Barr virus early antigen activation assay and in two-stage mouse skin carcinogenesis models.
- Author
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Kapadia GJ, Rao GS, Sridhar R, Ichiishi E, Takasaki M, Suzuki N, Konoshima T, Iida A, and Tokuda H
- Subjects
- 9,10-Dimethyl-1,2-benzanthracene toxicity, Administration, Cutaneous, Administration, Oral, Animals, Antigens, Viral biosynthesis, Antineoplastic Agents, Phytogenic chemistry, Antineoplastic Agents, Phytogenic isolation & purification, B-Lymphocytes drug effects, B-Lymphocytes pathology, B-Lymphocytes virology, Carcinogenesis pathology, Cell Line, Tumor, Female, Herpesvirus 4, Human drug effects, Herpesvirus 4, Human physiology, Humans, Male, Naphthoquinones chemistry, Naphthoquinones isolation & purification, Papilloma chemically induced, Papilloma pathology, Plant Extracts chemistry, Plant Extracts isolation & purification, Skin Neoplasms chemically induced, Skin Neoplasms pathology, Tetradecanoylphorbol Acetate pharmacology, Ultraviolet Rays, Antineoplastic Agents, Phytogenic administration & dosage, Carcinogenesis drug effects, Lawsonia Plant chemistry, Naphthoquinones administration & dosage, Papilloma prevention & control, Plant Extracts administration & dosage, Plant Leaves chemistry, Skin Neoplasms prevention & control
- Abstract
In continuation of our studies with chemoprevention potential of plant-derived naphthoquinone derivatives, leaf powder of the medicinal plant Lawsonia inermis L, commonly known as 'henna', was evaluated by its inhibition of the Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. Lawsone (2-hydroxy- 1,4-naphthoquinone), the reddish orange pigment artifact formed during the extraction or preparation of the dye from henna leaves and believed to be the active component, was also assessed in this in vitro assay. Both showed a profound inhibition (>88%) of EBV-EA activation. In the in vivo two-stage mouse skin carcinogenesis study using UV-B radiation for initiation and TPA for tumor promotion, oral feeding of henna (0.0025%) in drinking water ad libitum decreased tumor incidence by 66% and multiplicity by 40% when compared to the positive control at 10 weeks of treatment. Similarly, in the above mouse model, orally fed lawsone (0.0025%) decreased tumor incidence by 72% and multiplicity by 50%. The tumor inhibitory trend continued throughout the 20-week test period. Similar antitumor activities were observed when henna (0.5 mg/ml) was applied topically on the back skin in the UV-B initiated, TPA promoted and peroxynitrite initiated, TPA promoted mouse skin carcinogenesis models. Topically applied lawsone (0.015 mg/ml) also exhibited similar protection against tumor formation in the 7,12-dimtehylbenz(a)anthracene induced and TPA promoted skin cancer in mice. Also, there was a delay of 1 to 2 weeks in tumor appearance in both henna and lawsone treated groups compared to control in all three test models. This study ascertains the skin cancer chemopreventive activity of henna leaf powder and lawsone when administered by either oral (through drinking water) or topical (by application on the back skin) routes. Further, it emphasizes the need for the evaluation of these henna-derived green chemopreventive candidates in combination with currently used sunscreen agents for complementary anticancer potential against UV-induced skin carcinogenesis.
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- 2013
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544. Structure elucidation and characterization of microbial 2-tridecyl sophorosides (biosurfactants).
- Author
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Recke VK, Park JB, Gerlitzki M, Hausmann R, Syldatk C, Wray V, Tokuda H, Suzuki N, and Lang S
- Subjects
- Carbohydrate Sequence, Chromatography, Thin Layer, Mass Spectrometry, Molecular Structure, Nuclear Magnetic Resonance, Biomolecular, Candida chemistry, Glucans chemistry, Surface-Active Agents chemistry
- Abstract
To produce novel types of sophorose lipids containing an odd number of carbon atoms in the lipophilic moiety, Candida bombicola ATCC 22214 was grown in 500-ml flask cultures with glucose as main carbon source, and additionally, 2-tridecanone as co-substrate. After solvent extraction, the crude product mixture was separated into pure fractions, and each fraction was analysed via NMR and mass spectroscopy. This effective strategy generated five new glycolipids, 2-tridecyl sophorosides, which differed in the number of glucose units, and acetyl and hydroxy groups, respectively. Based on these compounds, a proposal for the possible biosynthetic pathway was deduced. Two compounds of the mixture, mono- and diacetylated 2-tridecyl sophorosides, respectively, were able to lower the surface tension of water from 72 mN m(-1) to 32 mN m(-1) and the interfacial tension between water and n-hexadecane from 43 mN m(-1) down to 4 and 3 mN m(-1). Thus, both compounds possess a very good surfactant behaviour. Moreover, it was observed that the new products inhibit the growth of particular Gram-positive bacteria, and they indicate potential for antitumour-promoting activity.
- Published
- 2013
545. Cancer chemopreventive effect of bergenin from Peltophorum pterocarpum wood.
- Author
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Zhang J, Nishimoto Y, Tokuda H, Suzuki N, Yasukawa K, Kitdamrongtham W, Akazawa H, Manosroi A, Manosroi J, and Akihisa T
- Subjects
- Animals, Anticarcinogenic Agents pharmacology, Anticarcinogenic Agents therapeutic use, Anticarcinogenic Agents toxicity, Antigens, Viral chemistry, Antigens, Viral metabolism, Apoptosis drug effects, Benzopyrans pharmacology, Benzopyrans therapeutic use, Cell Line, Tumor, Fabaceae metabolism, Free Radical Scavengers isolation & purification, Gallic Acid pharmacology, Gallic Acid therapeutic use, HL-60 Cells, Humans, Melanins antagonists & inhibitors, Melanins metabolism, Mice, Plant Extracts chemistry, Plant Extracts pharmacology, Plant Extracts therapeutic use, Skin Neoplasms drug therapy, Skin Neoplasms prevention & control, Anticarcinogenic Agents chemistry, Benzopyrans chemistry, Fabaceae chemistry, Free Radical Scavengers chemistry, Gallic Acid chemistry
- Abstract
The aqueous extract of Peltophorum pterocarpum (Fabaceae) wood exhibited potent inhibitory effects against EpsteinBarr virus early antigen (EBV-EA) activation induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells and against melanogenesis in α-melanocyte-stimulating hormone (α-MSH)-stimulated B16 melanoma cells, as well as potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging activity. Two phenolic acid derivatives, bergenin (1) and gallic acid (2), were isolated from the ethyl acetate (AcOEt)-soluble fraction obtained from the extract. Compound 1 exhibited potent inhibitory effect against EBV-EA activation and against skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter. Both compounds 1 and 2 exhibited melanogenesis-inhibitory activities in α-MSH-stimulated B16 melanoma cells, and, in addition, compound 2 showed strong DPPH radical-scavenging activity., (Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.)
- Published
- 2013
- Full Text
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546. Biological activities of phenolic compounds and triterpenoids from the galls of Terminalia chebula.
- Author
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Manosroi A, Jantrawut P, Ogihara E, Yamamoto A, Fukatsu M, Yasukawa K, Tokuda H, Suzuki N, Manosroi J, and Akihisa T
- Subjects
- Animals, Blotting, Western, Cell Line, Tumor, Cell Proliferation drug effects, Free Radical Scavengers chemistry, Free Radical Scavengers isolation & purification, Free Radical Scavengers pharmacology, HL-60 Cells, Humans, Hyperpigmentation drug therapy, Inflammation drug therapy, Melanins antagonists & inhibitors, Methanol chemistry, Mice, Molecular Structure, Neoplasms drug therapy, Phenols chemistry, Phenols pharmacology, Terminalia chemistry, Triterpenes chemistry, Triterpenes pharmacology
- Abstract
Nine phenolic compounds, including two phenolic carboxylic acids, 1 and 2, seven hydrolyzable tannins, 3-9, eight triterpenoids, including four oleanane-type triterpene acids, 10-13, and four of their glucosides, 14-17, isolated from a MeOH extract of the gall of Terminalia chebula Retz. (myrobalan tree; Combretaceae), were evaluated for their inhibitory activities against melanogenesis in B16 melanoma cells induced by α-melanocyte-stimulating hormone (α-MSH), against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells, and against TPA-induced inflammation in mice. Their 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activities and cytotoxic activities against four human cancer cell lines were also evaluated. Compounds 6-9 and 12 exhibited potent inhibitory activities against melanogenesis (39.3-66.3% melanin content) with low toxicity to the cells (74.5-105.9% cell viability) at a concentration of 10 μM. Western-blot analysis revealed that isoterchebulin (8) reduced the protein levels of MITF (=microphtalmia-associated transcription factor), tyrosinase, and TRP-1 (=tyrosine-related protein 1), mostly in a concentration-dependent manner. Eight triterpenoids, 10-17, showed potent inhibitory effects on EBV-EA induction with the IC50 values in the range of 269-363 mol ratio/32 pmol TPA, while these compounds exhibited no DPPH scavenging activities (IC50 >100 μM). On the other hand, the nine phenolic compounds, 1-9, exhibited potent radical-scavenging activities (IC50 1.4-10.9 μM) with weak inhibitory effects on EBV-EA induction (IC50 460-518 mol ratio/32 pmol TPA). The tannin 6 and seven triterpenoids, 10-16, have been shown to inhibit TPA-induced inflammation (1 μg/ear) in mice with the ID50 values in the range of 0.06-0.33 μmol/ear. Arjungenin (10) exhibited inhibitory effect on skin-tumor promotion in an in vivo two-stage mouse-skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator and with TPA as promoter. Compounds 1, 2, 4, 5, 7-9, 12, and 13, against HL60 cell line, compounds 1 and 4, against AZ521 cell line, and compounds 1, 11, and 12, against SK-BR-3 cell line, showed moderate cytotoxic activities (IC50 13.9-73.2 μM)., (Copyright © 2013 Verlag Helvetica Chimica Acta AG, Zürich.)
- Published
- 2013
- Full Text
- View/download PDF
547. Synergistic cytotoxicity of red beetroot (Beta vulgaris L.) extract with doxorubicin in human pancreatic, breast and prostate cancer cell lines.
- Author
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Kapadia GJ, Rao GS, Ramachandran C, Iida A, Suzuki N, and Tokuda H
- Subjects
- Antineoplastic Agents pharmacology, Cell Line, Tumor, Cell Survival drug effects, Doxorubicin pharmacology, Drug Combinations, Drug Synergism, Female, Herb-Drug Interactions, Humans, MCF-7 Cells, Male, Plant Extracts pharmacology, Plant Extracts therapeutic use, Antineoplastic Agents therapeutic use, Beta vulgaris, Breast Neoplasms drug therapy, Doxorubicin therapeutic use, Pancreatic Neoplasms drug therapy, Phytotherapy, Prostatic Neoplasms drug therapy
- Abstract
Although a wide variety of cytotoxic plant extracts and phytochemicals are known to act synergistically with anticancer drug doxorubicin (D), their clinical application is hindered by safety concerns of such combination therapy. Our earlier studies showed that red beetroot (Beta vulgaris L.) extract (B), approved by Food and Drug Administration and European Union as red food color E162, reduced multi-organ tumor formations in various animal models when administered in drinking water. This led us to postulate that a long-term daily exposure to low doses of B through diet might be safe and sufficient to produce cancer chemopreventive effect in humans. Further, our recent comparative cytotoxic investigation with B and D in several human cancer cell lines indicated their potential for synergistic activity. Since B is considered safe for human use with no known toxicity, we conducted the present study to evaluate its synergistic antiproliferative activity with D against pancreatic (PaCa), breast (MCF-7) and prostate (PC-3) tumor cells of human origin. Different concentrations of B and D (0.29-290 μg/ml) and in various combinations (B:D ratio = 1:0, 1:1, 5:1, 1:5 and 0:1) were tested for cytotoxic effects against the three cancer cells. The viability of cells was assessed after 72 h incubation with various combinations of B and D using the trypan-blue staining method. The cytotoxic data were analyzed by the combination index method of Chou and Talalay to establish synergy between B and D. The results indicated that an overall positive reduction in drug concentration was achieved by D when combined with B in its cytotoxicity profile in the three human cancer cells tested. The synergistic cytotoxicity was best when the B:D ratio of 1:5 was used in PaCa cells at IC50, IC75 and IC90 dose levels and in MCF-7 cells at IC90 dose level. These results warrant further studies on the potential of red beetroot extract-doxorubicin combination in treating human cancers.
- Published
- 2013
- Full Text
- View/download PDF
548. Oral chemoprevention of skin cancer in mice by benzophenone sunscreens dioxybenzone and octabenzone in drinking water.
- Author
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Rao GS, Tokuda H, Ichiishi E, Takasaki M, Iida A, Suzuki N, Konoshima T, and Kapadia GJ
- Subjects
- Animals, Anticarcinogenic Agents therapeutic use, Benzophenones therapeutic use, Cell Transformation, Neoplastic, Drinking Water, Female, Mice, Mice, Hairless, Sunscreening Agents therapeutic use, Anticarcinogenic Agents administration & dosage, Benzophenones administration & dosage, Skin Neoplasms drug therapy, Skin Neoplasms prevention & control, Sunscreening Agents administration & dosage
- Abstract
Background: Sunscreen compounds with added benefit of skin cancer prevention have both public and commercial interests. Our earlier study using the Epstein-Barr virus early antigen in vitro assay reported on skin cancer chemoprevention potential of benzophenone sunscreens. We now report the in vivo antitumor activity of two of the benzophenone sunscreens which tested positively in the in vitro assay, octabenzone (UV-1) and dioxybenzone (UV-2), in the two-stage mouse skin carcinogenesis model using (±)-(E)-4-methyl-2-[-(E)-hydroxyamino]-5-nitro-6-methoxy-3-hexanamide (NOR-1) as inducer and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) as promoter., Materials and Methods: Pathogen-free, female hairless mice of HOS:HR-1 strain, 15 animals per control and test groups, were used. Skin tumors were induced by a single dose of NOR-1 (390 nmol in 100 μl of acetone). One week later, TPA (1.7 nmol in 100 μl of acetone) was applied to skin twice weekly for 20 weeks as tumor a promoter. The test compounds UV-I or UV-2 were administered at 0.0025% to mice through drinking water ad libitum, starting one week prior to and stopping one week after tumor initiation. All animals were examined weekly for the development of skin papillomas., Results: In both UV-1- and UV-2-treated mice, a two-week delay in tumor appearance, and significant inhibition (p<0.001) of tumor incidence (50% and 60%, respectively) and tumor burden (papilloma inhibition/mouse, 50% and 70%, respectively) were observed when compared to the positive control group. UV-2 (dihydroxy derivative) was a more potent inhibitor of skin tumor than UV-1 (monohydroxy derivative), which followed their antioxidant activity ranking., Conclusion: The results affirm the skin cancer chemoprevention potential of orally-ingested benzophenone sunscreens in mice and warrant studies in humans to validate synergistic protection achievable by complementation of oral and topical sunscreen usage.
- Published
- 2013
549. Chemopreventive effect of sarcophine-diol on NOR-1-induced TPA-promoted skin carcinogenesis in female HOS:HR-1 mice.
- Author
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Szymanski PT, Ahmed SA, Khalifa S, Tokuda H, Ichiishi E, Iida A, Suzuki N, and Fahmy H
- Subjects
- Animals, Female, Mice, Mice, Hairless, Tetradecanoylphorbol Acetate, Anticarcinogenic Agents pharmacology, Diterpenes pharmacology, Hydroxylamines pharmacology, Skin Neoplasms prevention & control
- Abstract
The cancer chemopreventive potential of sarcophine-diol in a chemical carcinogen initiation-promotion experimental tumor model in mice was evaluated. Sarcophine-diol, when given orally, afforded significant protection in the mouse skin cancer model initiated by the topical administration of (+/-)-(E)-4-methyl-2-[(E)-hydroxyamino]-5-nitro-6-methoxy-3-hexanamide (NOR-1) and promoted by 12-O-tetradecanoylphorbol-13-acetate (TPA). These findings, along with our initial reports, suggest that sarcophine-diol is an effective cancer chemopreventive agent, even when administered orally and at a very low dose and thus indicating possible potential human applications in the control of malignancy.
- Published
- 2013
550. Anti-oxidative, anti-tumor-promoting, and anti-carcinogenic activities of adonirubin and adonixanthin.
- Author
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Maoka T, Yasui H, Ohmori A, Tokuda H, Suzuki N, Osawa A, Shindo K, and Ishibashi T
- Subjects
- 9,10-Dimethyl-1,2-benzanthracene antagonists & inhibitors, Animals, Anticarcinogenic Agents chemistry, Anticarcinogenic Agents metabolism, Antineoplastic Agents chemistry, Antineoplastic Agents metabolism, Antioxidants chemistry, Antioxidants metabolism, Canthaxanthin biosynthesis, Canthaxanthin chemistry, Canthaxanthin pharmacology, Carotenoids biosynthesis, Carotenoids chemistry, Cell Line, Tumor, Dose-Response Relationship, Drug, Drug Screening Assays, Antitumor, Female, Humans, Lipid Peroxidation drug effects, Mice, Mice, Inbred ICR, Molecular Structure, Paracoccus chemistry, Paracoccus metabolism, Singlet Oxygen chemistry, Skin Neoplasms chemically induced, Structure-Activity Relationship, Tetradecanoylphorbol Acetate antagonists & inhibitors, Anticarcinogenic Agents pharmacology, Antineoplastic Agents pharmacology, Antioxidants pharmacology, Canthaxanthin analogs & derivatives, Carotenoids pharmacology, Skin Neoplasms drug therapy, Viral Matrix Proteins antagonists & inhibitors
- Abstract
Anti-oxidative, anti-tumor-promoting, and anti-carcinogenic activities of adonirubin and adonixanthin, which are biosynthetic intermediates from β-carotene to astaxanthin, were investigated. Both adonirubin and adonixanthin showed almost the same activities for inhibition of lipid peroxidation and quenching of singlet oxygen as those of astaxanthin. Furthermore, adonirubin and adonixanthin exhibited an inhibitory effect on Epstein-Barr virus early antigen activation in Raji cells and carcinogensis of mouse skin tumors initiated by 7,12-dimethylbenz[a]anthracene and promoted by 12-O-tetradecanoylphorbol-13-acetate.
- Published
- 2013
- Full Text
- View/download PDF
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