Alkaline phosphatase inactivation by mixed function oxidation systems

Mordente, Alvaro; Miggiano, Giacinto Abele Donato; Martorana, Giuseppe; Meucci, Elisabetta; Santini, Stefano Angelo; Castelli, A

doi:10.1016/0003-9861(87)90334-1

Cited by 31 publications

(12 citation statements)

References 48 publications

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“…Nevertheless, the hydroxyl radical is known to oxidize amino acids in proteins resulting in a decrease of their biological activity. As recently reported, L-glutamine synthetase and alkaline phosphatase are readily inactivated by the xanthine oxidase system in the presence of 02 and of a suitable donor (xanthine or acetaldehyde) when Fe(II1) ions are available [39,40]. In both enzymes, a site-specific attack of the reactive oxygen species at or near the active center is assumed to be responsible for loss of enzyme activity.…”

Section: Discussionmentioning

confidence: 92%

Different selectivities of oxidants during oxidation of methionine residues in the α‐1‐proteinase inhibitor

Maier¹,

Matějková²,

Hinze³

et al. 1989

FEBS Letters

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myeloperoxidase/H,O,/chloride system and the related compound NH,CI. With taurine monochloramine, another myeloperoxidase-related oxidant, 1.05 mol Met(O) were generated per mol a-l-PI during inactivation. These oxidants attack preferentially one Met residue in a-l-PI, which is identical with Met 358, as concluded from the parallelism of loss of elastase inhibitory activity and oxidation of Met. A similar high specificity for Met oxidation was determined for the xanthine oxidase-derived oxidants. In contrast, the ratio found for ozone and m-chloroperoxybenzoic acid was 6.0 and 5.0, respectively, indicating oxidation of additional Met residues besides the reactive site Met in a-l-PI, i.e. unselective action of these oxidants. Further studies were performed on the efficiency of oxidants for total depletion of the elastase inhibitory capacity of a-l-PI. Ozone and m-chloroperoxybenzoic acid were IO-fold less effective and the superoxide anion/hydroxyl radicals were 3&50-fold less effective to inactivate the elastase inhibitory activity as compared to the myeloperoxidase-derived oxidants. The myeloperoxidase-related oxidants are discussed as important regulators of a-l-PI activity in vivo.

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Section: Discussionmentioning

confidence: 92%

Different selectivities of oxidants during oxidation of methionine residues in the α‐1‐proteinase inhibitor

Maier¹,

Matějková²,

Hinze³

et al. 1989

FEBS Letters

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“…We showed that the addition of deferoxamine plus DTI" could not normalize the impaired ATPasc activity, if the treatment was delayed for some time; the enzyme activity remained depressed, whether deferoxamine plus DTT was added or catalase was added to the ATPase preparation, in agreement with the above suggestion. Likewise, changes by other oxidants in glutamate synthetase, alkaline phosphatase, Ca 2+ ATPase and acetylcholine esterase were reported by several invcstigators to be irreversible (19,22,27,28). Therefore, in situations where rcperfusion risks are expected, e.g., organ transplantation, thrombolysis and coronary recanalization, preventive maneuvers or early interventions are essential.…”

Section: Discussionmentioning

confidence: 94%

“…The effective antagonism by superoxide dismutase, which converts superoxide anions to H202, indicates that depletion of superoxide anions restricts reduction of the chelated iron required for the generation of hydroxyl radicals (see formula above). ATP was effective in preventing the oxy radical-induced enzyme inhibition; the presence of substrate of an enzyme reaction is known to impede the advance of oxidative modification of the enzyme (7,22). The action of DTT on oxy radical-induced ATPase inhibition was biphasic in that low concentrations (0.01-10 mM) of DTI" significantly potentiated inhibition of ATPase activity by acting as a redox catalyst, Fe 3+ + DTF = Fe z+ + oxidized DTF Fe z+ + H202 -'-Fe 3+ + OH-+ OH', while high concentrations (> 100 mM) neither potentiated nor diminished H202 effccts (Fig.…”

Section: Resultsmentioning

confidence: 99%

Effect of oxidants on Na,K,ATPase and its reversal

1990

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Ischemia-reperfusion heart cell injury may be mediated, at least in part, through the generation of oxy radicals. Therefore, mechanisms of action of two oxidants on a membrane model, partially purified Na,K,ATPase, were investigated. Effects of H2O2, an oxygen intermediate postulated to play a primary role in reperfusion injury, on the function of the enzyme were time-dependent and potentiated by Fe ions. The inhibition of enzyme activity was prevented by chelators, but not by hydroxyl radical scavengers. The results support the view that the possible mode of enzyme modification involves H2O2-derived, Fe ion-catalyzed, localized ("site-specific") hydroxyl radical formation. The action of hypochlorous acid (HOCl), a powerful oxidant postulated to be produced by activated neutrophils, was quantitatively similar to that of H2O2 plus Fe ions in causing enzyme dysfunction. This is partly because relatively large doses of oxidants were required, due to the presence of physiological anti-oxidant defense mechanisms in the membrane. Although a combination of deferoxamine (Fe ion chelator) and dithiothreitol (DTT) (sulfhydryl reducing agent) was most effective in preventing the enzyme modification, once enzyme inactivation by oxidants is in progress, deferoxamine plus DTT could only arrest further deterioration of the enzyme function. Therefore, the oxidant-induced change in membrane dysfunction advances with time; the advance can be stalled, but the enzyme activity cannot be restored to normal.

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“…It is well documented that the lipid peroxidation by superoxide radicals or hydrogen peroxide in vivo depends upon a conversion of these peroxides into more reactive species, such as hydroxyl radicals [29,30]. In fact, Dudeja and Brastitus [31] demonstrated that hydroxyl radicals play an important role in lipid peroxidation induced by the Fe 2+ /ascorbate system in tissue homogenate.…”

Section: Nonsteroidal Anti-inflammatory Drugs Andmentioning

confidence: 99%

Effects of Zinc Acexamate (NAS-501) on Superoxide Radicals and Lipid Peroxidation of Rat Gastric Mucosa

Tsutsui

Nakamura²,

Yamaguchi³

et al. 1999

Pharmacology

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Zinc acexamate (NAS-501), an anti-ulcer agent, has been reported to prevent various acute experimental gastric mucosal lesions and duodenal ulcers in rats. In order to clarify the mechanisms by which NAS-501 exhibits the anti-ulcer effects, we investigated the anti-oxidative effects of NAS-501 in vitro and in vivo. NAS-501 significantly reduced the superoxide radical-dependent chemiluminescence, generated by hypoxanthine-xanthine oxidase, rat neutrophils and guinea-pig macrophages in vitro. These in vitro effects were also confirmed by electron spin resonance using a 5,5-dimethyl-1-pyrroline-N-oxide spin-trapping method. In addition, NAS-501 significantly inhibited lipid peroxidation induced by increasing concentrations of Fe²⁺/ascorbate in rat gastric mucosal homogenate in vitro. Oral administration of NAS-501 (30 mg/kg) significantly inhibited production of thiobarbituric acid-reactive substance in rat gastric mucosa following per os instillation of 60% ethanol in 150 mmol/l HCl in vivo. These results suggest that NAS-501 exhibits the preventive effect from acute gastric mucosal lesions by the anti-oxidative activity.

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Alkaline phosphatase inactivation by mixed function oxidation systems

Cited by 31 publications

References 48 publications

Different selectivities of oxidants during oxidation of methionine residues in the α‐1‐proteinase inhibitor

Different selectivities of oxidants during oxidation of methionine residues in the α‐1‐proteinase inhibitor

Effect of oxidants on Na,K,ATPase and its reversal

Effects of Zinc Acexamate (NAS-501) on Superoxide Radicals and Lipid Peroxidation of Rat Gastric Mucosa

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