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      • GROWTH INHIBITION OF Acanthamoeba BY HYDROPEROXYNAPHTALIMIDES UPON PHOTOIRRADIATION

        Matsugo, Seiichi,Takeuchi, Rie,Takehara, Yoshimi,Tsuruhara, Takashi Korean Society of Photoscience 1997 Journal of Photosciences Vol.4 No.3

        Acanthamoeba strains were photoirradiated in the presence of light-sensitive organic peroxides (hydroperoxynaphthalimide derivatives) including a Photo-Fenton reagent at 366 nm. The survival rates of Acantharnoeba strains determined after 20 h culture showed a significant decrease only upon photoirradiated conditions. The most effective hydroperoxynaphthalimides among these compounds was the bromohydroperoxynaphthalimide (Br-HPO II). The minimum inhibitory concentration (MIC) of Br-HPO II is 100 times lower than that of hydrogen peroxide.

      • Artificial Radical Generating and Scavenging Systems: Synthesis and Utilization of Photo-Fenton Regent in Biological Systems

        Matsugo, Seiichi Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

        A photo-labile compound which is bioinactive but, upon irradiation with light, yields bioactive species is called as "caged compound". Photolysis of caged compounds generating bioactive species, has become a general method to produce a desired amounts of bioactive species in the specific time interval at the desired place or area of the target biological systems. For this purpose, we designed and synthesized caged hydroxyl radical., "Photo-Fenton Reagent" NP-IIl. NP-IIl has a strong absorption maximum at 377 nm and yields hydroxyl radicals upon UV light irradiation. The antioxidant activity of the ${\alpha}$ -lipoic acid and other naturally occurring compounds has been examined by using NP-IIl as a molecular probe. For example, upon photoirradiation of NP-lII with BSA or apolipoprotein of human low density (LDL), the significant oxidative modifications were observed in both cases. The oxidation was completely suppressed in the presence of ${\alpha}$-lipoic acid, which clearly demonstrates the strong hydroxyl radical scavenging activity of ${\alpha}$-lipoic acid. Other applications of NP-lII will also be described

      • Component analysis of the lipid hydroperoxide in the brain and peripheral organs of Senescence-Accelerated Mouse (SAM) model

        Matsugo, Seiichi,Yasui, Fumihiko,Sasaki, Kazuo Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

        We measured previously the lipid hydroperoxides level in the brain and peripheral organs such as heart, liver, lung and kidney of senescence acceIerated-prone (SAMP8) and -resistant(SAMR1) mice at 3,6 and 9 months of age. It was found that the lipid hydroperoxide leve1s in the brain did not show any age-dependent change, and that they Were significantly higher in SAMP8 than in SAMR1 over the defined periods. In contrast, the lipid hydroperoxide leve1s in the peripheral organs, including liver, Were increased with aging in both substrain, and they were significantly higher in SAMP8 than in SAMR1 at 3 and 6 months of age. In addition, the lipid hydroperoxide levels in the peripheral organs were higher than those in the brain in both substrains. To elucidate the difference of lipid hydroperoxide levels between the brain and the peripheral organs, we further carried out lipid component analysis in the brain and liver, one of the peripheral organs, of SAMP8 and SAMR1 at 6 months of age.

      • Research in the antioxidant of Phellinus linteus mycelia

        Nakamura, Tomoyuki,Akiyama, Yukihito,Matsugo, Seiichi,Shibata, Keiji,Kawagishi, Hirokazu Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

        Phellinus linteus mycelia have many pharmacological effects, although their pharmacological efficacy principles have not been known yet. In the course of screening for biological activity of the extracts of Phellinus linteus mycelia, we found strong antioxidative activity in some fraction of water-insoluble. Therefore, we tried to isolate the active principle(s) from the extract. The isolation of the active compound was guided by superoxide anion radical scavenging activity. As a result, caffeic acid was isolated as an active compound. The IC$\_$50/ of the compound was 3.05 $\mu$g/ml (16.9$\mu$M).

      • KCI등재

        Cancer Cell Cytotoxicity of Extracts and Small Phenolic Compounds from Chaga [Inonotus obliquus (persoon) Pilat]

        Nakajima, Yuki,Nishida, Hiroshi,Matsugo, Seiichi,Konishi, Tetsuya The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.3

        Previously, we studied the antioxidant potential of Chaga mushroom [Inonotus obliquus (persoon) Pilat] extracts and isolated several small (poly)phenolic compounds as the major antioxidant components in the 80% methanol (MeOH) extract. In the present study, these isolated phenolic ingredients together with several other types of Chaga extracts were examined for cytotoxic effects against normal (IMR90) and cancer (A549, PA-1, U937, and HL-60) cell lines. Results revealed decoctions from both the fruiting body (FB) and sclerotium (ST) parts of Chaga, especially the ST part, showed considerable cytotoxicity toward tumor cells, but the cytotoxicity appeared to be stronger against normal cells than cancer cells. The 80% MeOH ST extract also showed the same trend. On the other hand, the 80% MeOH extract of FB showed significant cytotoxicity towards tumor cell lines without affecting normal cells, for example, the 50% lethal dose was $49.4\;{\pm}\;2.9\;{\mu}g/mL$ for PA-1 cells versus $123.6\;{\pm}\;13.8\;{\mu}g/mL$ for normal cells. The phenolic components isolated from the 80% MeOH extracts had markedly greater cancer cell toxicity than the extracts themselves. In particular, two out of seven compounds showed strong cytotoxicity towards several tumor cell lines without giving rise to significant cell toxicity toward normal cells. For example, the 50% lethal dose for 3,4-dihydroxybenzalacetone was $12.2\;{\mu}mmol/L$ in PA-1 cells but was $272.8\;{\mu}mmol/L$ in IMR90 cells. Fluorescence-activated cell sorting analysis further revealed these phenolic ingredients have high potentiality for apoptosis induction in PA-1 cells.

      • The Effects of Visible Light on Iron Release from Ferritin Related to Lipid Peroxidation in the Retina

        Ohishi, Kentaro,Hiramitsu, Tadahisa,Matsugo, Seiichi Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

        We studied iron release from ferritin by irradiating the visible light, and then followed ferritin-mediated lipid peroxidation in the rod outer segment (ROS) fraction of the porcine retina. In the presence of several phosphorus compounds such as ADP and ATP, iron release from ferritin at pH 7.0 could be induced by irradiation of the visible light to the reaction mixtures. Furthermore, iron release from ferritin in the presence of ADP depended on the incubation time and the visible light irradiation. Moreover, we investigated lipid peroxidation level in the ROS fraction by two independent assay systems including the thiobarbituric acid (TBA) and ferrous oxidation/xylenol orange (FOX) methods. The visible light induced ferritin-mediated lipid peroxidation in the ROS fraction in time- and irradiance-dependent manners. In the dark condition, iron release and lipid peroxidation were not observed. Iron release from ferritin by irradiating the visible light may play an important role in the etiology of phototoxic injuries in vivo.

      • Structural Determination of Oxidation Products of Flavonoids in Alcoholic Aqueous Solution with Reactive Oxygen Species

        Hirose, Yuko,Kakita, Mitsuko,Washizu, Toshiyuki,Matsugo, Seiichi Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

        Recently, much attention has been paid to the physiological functions of flavonoids associated with their antioxidant properties. However, there was a lack of information on the molecular mechanism at which flavonoids play the antioxidative role. We have already studied on the oxidation of quercetin with hydrogen peroxide and sodium hypochlorite in alcoholic aqueous solution and determined the oxidation products. Through the structural analysis of the oxidation products, it was clarified that the hydroxyl group at C-3 in the C ring plays the important role in the antioxidative action of quercetin. Successively, rutin and (+)-catechin were oxidized with sodium hypochlorite and their mono- and di-chlorinated derivatives were obtained. These facts indicate that these flavonoids can directly scavenge hypochlorous acid and the active site in this scavenging reaction is not the hydroxyl group at C-3.

      • KCI등재

        Cancer Cell Cytotoxicity of Extracts and Small Phenolic Compounds from Chaga [Inonotus obliquus (persoon) Pilat]

        Yuki Nakajima,Hiroshi Nishida,Seiichi Matsugo,Tetsuya Konishi 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.3

        Previously, we studied the antioxidant potential of Chaga mushroom [Inonotus obliquus (persoon) Pilat] extracts and isolated several small (poly)phenolic compounds as the major antioxidant components in the 80% methanol (MeOH) extract. In the present study, these isolated phenolic ingredients together with several other types of Chaga extracts were examined for cytotoxic effects against normal (IMR90) and cancer (A549, PA-1, U937, and HL-60) cell lines. Results revealed decoctions from both the fruiting body (FB) and sclerotium (ST) parts of Chaga, especially the ST part, showed considerable cytotoxicity toward tumor cells, but the cytotoxicity appeared to be stronger against normal cells than cancer cells. The 80% MeOH ST extract also showed the same trend. On the other hand, the 80% MeOH extract of FB showed significant cytotoxicity towards tumor cell lines without affecting normal cells, for example, the 50% lethal dose was 49.4±2.9μg/mL for PA-1 cells versus 123.6±13.8μg/mL for normal cells. The phenolic components isolated from the 80% MeOH extracts had markedly greater cancer cell toxicity than the extracts themselves. In particular, two out of seven compounds showed strong cytotoxicity towards several tumor cell lines without giving rise to significant cell toxicity toward normal cells. For example, the 50% lethal dose for 3,4-dihydroxybenzalacetone was 12.2μmol/L in PA-1 cells but was 272.8μmol/L in IMR90 cells. Fluorescence-activated cell sorting analysis further revealed these phenolic ingredients have high potentiality for apoptosis induction in PA-1 cells.

      • PREVENTION OF HYDROXYL RADICAL-INDUCED ERYTHROCYTE HEMOLYSIS BY PROTEIN THIOLS

        Youn, Hong-Duk,Packer, Lester,Matsugo, Seiichi Korean Society of Photoscience 1997 Journal of Photosciences Vol.4 No.3

        A system for studying oxidative hemolysis has been used by controling UV-irradiation and concentration of a novel molecular probe, N,N'-bis(2-hydroperoxy-2-methoxyethyl)-1,4,5,8-naphthalenetetra-carboxylic diimide (NP-III), which generates hydroxyl radical upon longer wavelength photoirradiation (> 350 nm). NP-III induces 25~30% of hemolysis at low concentration (50 $\mu$M) for 3h-irradiation of UVA. The simultaneous treatment of N-ethylmaleimide (NEM) with NP-IH completely hemotyzed erythrocytes under the same conditions as NP-III alone by both decreasing thiol group and increasing lipid peroxidation in erythrocyte membrane. However. thiol-reducing agents prevented the protein-crosslinking and lipid peroxidation on the NEM-synergistic hemolysis by partially scavenging hydroxyl radical and maintaining the thiol group of erythrocyte membrane in the reduced state. In addition, erythrocytes pretreated with 2,2,5,7,8-pentamethyl-6-hydroxychromane (PMC), vitamin E homologue was able to delay and decrease the lipid peroxidation when compared to cells pretreated with both NEM and PMC. We suggest that the presence of reduced thiols in inner membrane protein by GSH can prevent the protein-crosslinking and the lipid peroxidation, and eventually prevent the oxidative hemolysis of erythrocyte.

      • Detection of Superoxide Anion and Singlet Oxygen in the Decomposition of Several Peroxovanadium(V) Complexes

        Kanamori, Kan,Hata, Kaori,Shimoyama, Toshiyuki,Hayakawa, Shingo,Tajima, Hirotaka,Matsugo, Seiichi Korean Society of Photoscience 2002 Journal of Photosciences Vol.9 No.2

        Several peroxovanadium(V) complexes with an organic chelate ligand decompose spontaneously, depending on the nature of the chelate ligand. The self-decomposition reactions of the dinuclear peroxovanadium(V) complex with 2-oxo-l,3-diaminopropane-N,N,N',N'-tetraacetate (dpot) and the peroxovanadium(V) complexes with N-carboxymethylhistidinate (cmhist) and histamine-N,N-diacetate (histada) accompany the reduction of vanadium(V) to vanadium(IV). This implies that the peroxide anion acts as a reducing agent and thus the peroxide is oxidized in the decomposition process of the peroxovanadium(V) complexes. The oxidized dioxygen species have been characterized spectrophotometrically. Superoxide anion has been detected in 2-3 % yields using the reduction of cytochrome c method and chemiluminescence method utilized MCLA as a fluorescer. Singlet oxygen has also been detected in higher yields on the basis of chemiluminescence of tryptophan.

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