Superoxide dismutase -like activity

Hirano T, Hirobe M, Kobayashi K, Odani A, Yamauchi O, Ohsawa M, Satow Y, Nagano T. (2000) Mechanism of superoxide dismutase-like activity of Fe(ll) and Fe(III) complexes of tetrakis-N,N,N ,N (2-pyridylmethyl)ethylenedi-amine. Chemioal and Pharmaoeutieal Bulletin 48 223-230. 

Marttila, R.J., Lorentz, H. and Rinne, U.K. (1988) Oxygen toxicity protecting enzymes in Parkinson s disease. Increase of superoxide dismutase-like activity in the substantia nigra and basal nucleus. ]. Neurol. Sci. 86 321-331... 

Superoxide dismutase-like activity Angiogenesis inhibition... 

Eyles, A., N. W. Davies, T. Mitsunaga, R. Mihara, and C. Mohammed. 2004. Role of Eucalyptus globulus wound wood extractives Evidence of superoxide dismutase-like activity. Forest Pathol. 34 225-232. 

The synthesis, structure, and superoxide dismutase mimetic activity in vitro and the protection against reactive oxygen species in vivo of mononuclear copper complexes with 2-(4-methylphenylsulfamoyl)-6-nitrobenzothiazole have been reported [602], Like 1,2,3-benzoxadiazoles, nitroderivatives of 1,2,3-benzothiadiazoles were obtained on diazotization of the corresponding or/Zzo-aminothiophcnolcs [213, 218, 583], The initial or/Zzo-thiophcnols for this reaction were synthesized by nucleophilic substitution of halogen in ort/zo-halogenoanilines. It turned out that 4-nitro- and... 

Low-dose irradiation with 50 cGy of X-ray induced in vivo production of superoxide dismutase-like substances and accelerated antioxidant activity in liver, brain and bone marrow of male C57BL/6 mice (Yamaoka et al. 1999). 

The solution produced in the cathodic con artment by electrolyzing a dilute solution of NaCl exhibits low dissolved oxygen and high dissolved hydrogen (i). These properties of the cathodic solution suggest that it is potentially usefiil for preventing the oxidation of polyunsaturated lipids and their related compounds in an aqueous systems. Furthermore, this solution is reported to have superoxide dismutase-like and catalase-Uke activities (7). However, this data has not yet been confirmed. 

Water soluble protein with a relative molecular mass of ca. 32600, which particularly contains copper and zinc bound like chelate (ca. 4 gram atoms) and has superoxide-dismutase-activity. It is isolated from bovine liver or from hemolyzed, plasma free erythrocytes obtained from bovine blood. Purification by manyfold fractionated precipitation and solvolyse methods and definitive separation of the residual foreign proteins by denaturizing heating of the orgotein concentrate in buffer solution to ca. 65-70 C and gel filtration and/or dialysis. 

The mitochondrial dysfunctionality seen in manganese neurotoxicity might be related to the accumulation of reactive oxygen species (Verity, 1999). Mitochondrial Mn superoxide dismutase (MnSOD) is found to be low or absent in tumour cells and may act as a tumour suppressor. It is induced by inflammatory cytokines like TNF, presumably to protect host cells. In a rat model, iron-rich diets were found to decrease MnSOD activity, although a recent study reported that in rat epithelial cell cultures iron supplementation increased MnSOD protein levels and activity, but did not compromise the ability of inflammatory mediators like TNF to further increase the enzyme activity (Kuratko, 1999). 

Peroxynitrite reacts with the active site of superoxide dismutase (SOD) to form a nitronium-like species (Fig. 37), analogous to the Fe EDTA reactions described earlier. However, copper in the active site of superoxide dismutase was necessary for the formation of the adduct. Removing copper from the active site by reduction with borohydride and dialysis against 50 mM KCN resulted in no adduct being formed, while restoration of copper to the active site gave back full enzyme activity. To account for the essential role of copper in the active site and the subsequent formation of 3-nitrotyrosine located 18-21 A distal from the active site, we proposed that peroxynitrite is attracted by the same electrostatic force field that draws superoxide into the active site (Beckman et al., 1992 Ischiropoulos et al., 1992b). Peroxynitrite appears to bind to copper in the active site to form a transient cuprous adduct as shown. 

Little information about the mechanism of action of flavonoids is anticipated from in vivo studies. The mechanism of catechin and morin seems to be related to an increase of the activity of detoxifying enzymes like glutathione-S-transferase and NADPH quinone reductase [198, 211]. Similarly, EGCG effect at the colonic level is associated to an increase in tissue superoxide dismutase levels, suggesting that it may act through a potentiation of the antioxidative defense [210]. 

Plasma malondialdehyde-like material, an indicator of lipid peroxidation, is increased in conditions of ischaemia, such as stroke [83, 84] and myocardial infarction [85]. Mitochondria extracted from hearts of vitamin-E-deficient rabbits showed a decreased mitochondrial function and an increased formation of oxygen radicals associated with a reduced superoxide dismutase activity. This was partially reversed by addition of vitamin E in vitro [86]. Measurement of in vitro susceptibility to lipid peroxidation in cardiac muscle from vitamin-E-deficient mice showed a highly significant negative correlation between the concentration of vitamin E and in vitro lipid peroxidation. The results indicate that short-term vitamin E deficiency may expose cardiac muscle to peroxidation injuries [ 87 ]. In rats, treatment for 2 days with isoprenaline increased lipid peroxide activity, as measured by malondialdehyde levels, in the myocardium. Vitamin-E-deficient animals were even more sensitive to this effect, and pretreatment with a-tocopheryl acetate for 2 weeks prevented the effect induced by isoprenaline. The authors [88] propose that free-radical-mediated increases in lipid peroxide activity may have a role in catecholamine-induced heart disease. 

Zini, A., de Lamirande, E., and Gagnon, C. 1993. Reactive oxygen species in semen of infertile patients Levels of superoxide dismutase and catalase-like activities in seminal plasma and spermatozoa. Int. J. Androl. 16, 183-188. 

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