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1.
Rev. lab. clín ; 7(3): 96-103, jul.-sept. 2014.
Article in Spanish | IBECS | ID: ibc-128922

ABSTRACT

Fundamento. Situaciones estresantes conducen a la formación de un exceso de radicales libres, que constituyen la mayor amenaza para la homeostasis celular de organismos aerobios. El burnout es un síndrome de estrés crónico laboral. Objetivos. 1. Determinar tanto el estrés oxidativo como el estrés laboral al que se encuentran sometidos profesionales sanitarios de un servicio de urgencias. 2. Analizar la influencia que la práctica de ejercicio físico puede ejercer tanto sobre el estrés oxidativo como sobre el estrés laboral de estos profesionales. Material y métodos. Se han analizado 70 profesionales de un servicio de urgencias hospitalarias y un grupo control de 80 individuos sanos y edades similares. En todos se determinó la actividad de superóxido dismutasa (SOD) y catalasa (CAT), los niveles de malondialdehído (MDA) y del burnout y sus componentes. Resultados. No se han observado diferencias significativas entre varones y mujeres ni en la actividad de SOD y CAT, ni en los niveles de MDA ni en los niveles del burnout. Los niveles de MDA aumentan con la edad en profesionales sanitarios y en el grupo control, con diferencias significativas entre distintos grupos de edad. El estado civil no influye en las variables analizadas. Conclusiones. La peroxidación lipídica y el estrés laboral (niveles de burnout) disminuyen con la práctica de ejercicio físico, siendo los niveles más bajos para los que hacen ejercicio diariamente. Hacer deporte habitualmente, sobre todo cuando no es agotador, resulta una práctica beneficiosa para la prevención tanto del estrés oxidativo como del estrés laboral (AU)


Background. Stressful conditions lead to the formation of excessive free radicals which represents the greatest threat to cellular homeostasis of aerobic organisms. Burnout is a syndrome of chronic occupational stress. Objectives. This work focuses on the determination of both oxidative stress and occupational stress in a medical emergency service staff, and to analyze the effect that performing physical exercise can have on oxidative and occupational stress in these professionals. Material and methods. The study sample consisted of 70 professionals working in a medical emergency service and a control group of 80 age-matched healthy individuals. Superoxide dismutase (SOD) and catalase (CAT) activities, and malondialdehyde (MDA) were determined, as well as burnout with its components. Results. No significant variations were observed in SOD, CAT, MDA, or burnout levels as regards to gender. MDA levels increased with age in both the medical emergency service staff and the control group, with significant differences between the medical emergency service staff and the control group for all age groups. Marital status does not influence the variables analyzed. Conclusions. Lipid peroxidation and occupational stress (burnout levels) decrease with physical exercise, being lower levels for those who practice it daily. Playing sports regularly, especially when it is not exhausting, is a beneficial practice for preventing both oxidative stress and occupational stress (AU)


Subject(s)
Humans , Male , Female , Exercise/physiology , Burnout, Professional/physiopathology , Burnout, Professional/therapy , Oxidative Stress/physiology , Enzymes , Lipid Peroxidation , Malondialdehyde/isolation & purification , Exercise/psychology , Burnout, Professional/complications , Burnout, Professional/diagnosis , Health Personnel/psychology , Health Personnel/trends , Superoxide Dismutase/chemical synthesis , Superoxide Dismutase
2.
Inorg Chem ; 52(7): 3653-62, 2013 Apr 01.
Article in English | MEDLINE | ID: mdl-23480026

ABSTRACT

Antioxidant therapies have been considered for a wide variety of disorders associated with oxidative stress, and synthetic catalytic scavengers of reactive oxygen species would be clinically superior to stoichiometric ones. Among them, salen-manganese complexes (Mn(Salen)) seem promising, because they exhibit dual functions, i.e. superoxide dismutase- and catalase-mimetic activities. We have been developing enzyme-mimetic Mn(Salen) complexes bearing a functional group that enhances their catalytic activity. Here, we describe the design and synthesis of novel Mn(Salen) complexes with general acid-base catalytic functionality, inspired by the reaction mechanism of catalase. As expected, these Mn(Salen) complexes showed superior catalase-like activity and selectivity, while retaining moderate SOD-like activity. An unsubstituted pyridyl group worked well as a functionality to promote catalase-like activity. The introduced functionality did not alter the redox potential suggesting that the auxiliary-modified complex acted as an acid-base catalyst analogous to catalase. We believe that our approach provides a new design principle for sophisticated catalyst design. Further, the compounds described here appear to be good candidates for use in antioxidant therapy.


Subject(s)
Antioxidants/chemical synthesis , Catalase/chemical synthesis , Ethylenediamines/chemical synthesis , Hydrogen Peroxide/chemistry , Organometallic Compounds/chemical synthesis , Superoxide Dismutase/chemical synthesis , Superoxides/chemistry , Antioxidants/chemistry , Catalase/chemistry , Catalysis , Cytochromes c/chemistry , Enzyme Assays , Ethylenediamines/chemistry , Hydrogen-Ion Concentration , Molecular Mimicry , Organometallic Compounds/chemistry , Structure-Activity Relationship , Superoxide Dismutase/chemistry
3.
Eur J Med Chem ; 46(3): 961-5, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21288604

ABSTRACT

The approach of non-covalent conjugation has recently been used and a number of metal complexes have been encaged in a protein scaffold to form functional metallo proteins. Here we investigate a novel artificial superoxide dismutase enzyme based on the non-covalent conjugation of bovine serum albumin and the manganese(III) complex of N,N'-bis(salicylidene)-3,4-diaminobenzoic acid. We report the intriguing ability of the albumin environment to increase the SOD activity of the inorganic complex. We also determined the binding constant with BSA by CD spectroscopy.


Subject(s)
Biomimetic Materials/chemistry , Manganese/chemistry , Salicylates/chemistry , Serum Albumin, Bovine/chemistry , Superoxide Dismutase/chemistry , Animals , Biomimetic Materials/chemical synthesis , Biomimetic Materials/metabolism , Cattle , Models, Molecular , Organometallic Compounds/chemistry , Spectrum Analysis , Superoxide Dismutase/chemical synthesis , Superoxide Dismutase/metabolism
4.
Int J Biol Macromol ; 47(5): 603-13, 2010 Dec 01.
Article in English | MEDLINE | ID: mdl-20723561

ABSTRACT

Hemoglobin (Hb) conjugated with the antioxidant enzymes (SOD and CAT), by employing dicarboxymethylated poly(ethylene glycol), was designed for protection of hemoglobin against free radicals. In this study, the conjugation process was confirmed by employing SDS-PAGE and SEC techniques. The average molecular weight of the conjugates was estimated to be around 1000 kDa. The enzymatic activities of the SOD and CAT in the conjugates (Hb-SOD-CAT) after conjugation were found to retain greater than 70% and 90% of the original bioactivity. Results show that antioxidant enzymes helped minimize methemoglobin (non-carrier of oxygen) formation during the conjugation process and also during storage at 4°C over a period of 1 month. In summary, the optimized (1:10 Hb/PEG) crosslinked conjugates with antioxidant enzymes showed protective properties from severe free radical stresses when incubated with hydrogen peroxide (0.1 and 1 mM) and xanthine (1 mM)/xanthine oxidase (10 and 20 mU/ml) system.


Subject(s)
Antioxidants/metabolism , Catalase/metabolism , Cross-Linking Reagents/metabolism , Free Radicals/toxicity , Hemoglobins/metabolism , Stress, Physiological/drug effects , Superoxide Dismutase/chemical synthesis , Animals , Cattle , Chromatography, Gel , Electrophoresis, Polyacrylamide Gel , Hydrogen Peroxide/toxicity , Methemoglobin/analysis , Polyethylene Glycols , Protective Agents/metabolism , Spectrum Analysis , Superoxide Dismutase/metabolism , Superoxides/toxicity
5.
Bioorg Chem ; 38(4): 159-64, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20363012

ABSTRACT

For constructing a bifunctional antioxidative enzyme with both superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities, a supramolecular artificial enzyme was successfully constructed by the self-assembly of the Mn(III)meso-tetra[1-(1-adamantyl methyl ketone)-4-pyridyl] porphyrin (MnTPyP-M-Ad) and cyclodextrin-based telluronic acid (2-CD-TeO(3)H) through host-guest interaction in aqueous solution. The self-assembly of the adamantyl moieties of Mn(III) porphyrin and the beta-CD cavities of 2-CD-TeO(3)H was demonstrated by the NMR spectra. In this supramolecular enzyme model, the Mn(III) porphyrin center acted as an efficient active site of SOD and tellurol moiety endowed GPx activity. The SOD-like activity (IC(50)) of the new catalyst was found to be 0.116 microM and equals to 2.56% of the activity of the native SOD. Besides this, supramolecular enzyme model also showed a high GPx activity, and a remarkable rate enhancement of 27-fold compared to the well-known GPx mimic ebselen was observed. More importantly, the supramolecular artificial enzyme showed good thermal stability.


Subject(s)
Adamantane/chemistry , Glutathione Peroxidase/chemistry , Porphyrins/chemistry , Superoxide Dismutase/chemistry , beta-Cyclodextrins/chemistry , Adamantane/chemical synthesis , Adamantane/metabolism , Catalytic Domain , Glutathione Peroxidase/chemical synthesis , Glutathione Peroxidase/metabolism , Kinetics , Manganese/chemistry , Manganese/metabolism , Porphyrins/chemical synthesis , Porphyrins/metabolism , Superoxide Dismutase/chemical synthesis , Superoxide Dismutase/metabolism , beta-Cyclodextrins/chemical synthesis , beta-Cyclodextrins/metabolism
6.
J Microbiol Biotechnol ; 20(1): 88-93, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20134238

ABSTRACT

Superoxide dismutase (SOD), glutathione peroxidase (GPX) and catalase (CAT) play crucial roles in balancing the production and decomposition of reactive oxygen species (ROS) in living organisms. These enzymes act cooperatively and synergistically to scavenge ROS. In order to imitate the synergism of these enzymes, we designed and synthesized a novel 32-mer peptide (32P) on the basis of the previous 15-mer peptide with GPX activity and a 17-mer peptide with SOD activity. Upon the selenation and chelation of copper, the 32-mer peptide is converted to a new Se- and Cu-containing 32-mer peptide (Se-Cu-32P) and displays both SOD and GPX activities and its kinetics was studied. Moreover, the novel peptide was demonstrated to be able to better protect vero cells from the injury induced by xanthine oxidase (XOD)/xanthine/Fe2+ damage system than its parents. Thus, this bifunctional enzyme imitated the synergism of SOD and GPX and could be a better candidate of therapeutic medicine.


Subject(s)
Glutathione Peroxidase/chemistry , Peptides/chemistry , Superoxide Dismutase/chemistry , Animals , Chlorocebus aethiops , Copper/chemistry , Glutathione Peroxidase/chemical synthesis , Glutathione Peroxidase/pharmacology , Kinetics , Oxidative Stress/drug effects , Peptides/chemical synthesis , Peptides/pharmacology , Selenium/chemistry , Superoxide Dismutase/chemical synthesis , Superoxide Dismutase/pharmacology , Vero Cells
7.
J Inorg Biochem ; 103(3): 381-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19135258

ABSTRACT

Mimetics of antioxidant enzymes such as superoxide dismutases (SOD) or catalases are reported as potential new drugs able to reduce oxidative stress damage. In particular, manganese(III) complexes of salen-type ligands have been studied as both SOD and catalase mimetics. In this paper, we report the synthesis of two novel conjugates of salen-type ligands with the beta-cyclodextrin, the 6-deoxy-6-[(S-cysteamidopropyl(1,2-diamino)N,N'-bis(salicylidene))]-beta-cyclodextrin and the 6-deoxy-6-[(S-cysteamidopropyl(1,2-diamino)N,N'-bis(3-methoxysalicylidene))]-beta-cyclodextrin, their spectroscopic characterization, and the synthesis and the characterization of their manganese(III) complexes. The SOD-like activity of the metal complexes was investigated by the indirect Fridovich method. The catalase like activity was tested using a Clark-type oxygen electrode. The peroxidase activity was tested using the ABTS (2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid)) assay. The glycoconjugation of salen-manganese(III) complexes yields compounds with enhanced SOD activity. These complexes also show catalase and peroxidase activities higher than the simple salen complexes (EUK 113 and EUK 108).


Subject(s)
Biomimetic Materials/chemistry , Catalase/chemistry , Copper/chemistry , Manganese/chemistry , Superoxide Dismutase/chemistry , beta-Cyclodextrins/chemistry , Biomimetic Materials/chemical synthesis , Catalase/chemical synthesis , Oxidative Stress , Peroxidase/chemical synthesis , Peroxidase/chemistry , Superoxide Dismutase/chemical synthesis , beta-Cyclodextrins/chemical synthesis
8.
J Inorg Biochem ; 103(2): 219-26, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19026447

ABSTRACT

The coordination behavior of copper(II) with tricarballylic acid (H(3)TCA) and imidazole (Imz) is described. Speciation in aqueous solution has been determined at 25 degrees C and 0.15M NaCl ionic strength by potentiometric measurements and EPR characterization of the species. Two new compounds CuTCAH.3H(2)O and CuTCAHImz.2H(2)O were obtained and characterized by elemental analysis diffuse reflectance, FTIR (Fourier transform infrared spectroscopy), EPR and thermal behavior. Their in vitro superoxide dismutase-mimetic activities have been tested.


Subject(s)
Copper/chemistry , Imidazoles/chemistry , Organometallic Compounds/chemistry , Superoxide Dismutase/chemistry , Tricarboxylic Acids/chemistry , Organometallic Compounds/chemical synthesis , Superoxide Dismutase/chemical synthesis
9.
Neurobiol Aging ; 29(1): 117-28, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17079053

ABSTRACT

In lower organisms, such as Caenorhabditis elegans and Drosophila, many genes identified as key regulators of aging are involved in either detoxification of reactive oxygen species or the cellular response to oxidatively-damaged macromolecules. Transgenic mice have been generated to study these genes in mammalian aging, but have not in general exhibited the expected lifespan extension or beneficial behavioral effects, possibly reflecting compensatory changes during development. We administered a small-molecule synthetic enzyme superoxide dismutase (SOD) mimetic to wild-type (i.e. non-transgenic, non-senescence accelerated) mice starting at middle age. Chronic treatment not only reduced age-associated oxidative stress and mitochondrial radical production, but significantly extended lifespan. Treated mice also exhibited improved performance on the Morris water maze learning and memory task. This is to our knowledge the first demonstration that an administered antioxidant with mitochondrial activity and nervous system penetration not only increases lifespan, but rescues age-related cognitive impairment in mammals. SOD mimetics with such characteristics may provide unique complements to genetic strategies to study the contribution of oxidative processes to nervous system aging.


Subject(s)
Aging/drug effects , Cognition/drug effects , Fullerenes/pharmacology , Superoxide Dismutase/pharmacology , Age Factors , Analysis of Variance , Animals , Behavior, Animal/drug effects , Body Weight/drug effects , Brain/ultrastructure , Ethidium/analogs & derivatives , Ethidium/metabolism , Female , Male , Maze Learning/drug effects , Mice , Mice, Inbred C57BL , Mitochondria/drug effects , Oxidative Stress/drug effects , Oxygen Consumption/drug effects , Sex Factors , Superoxide Dismutase/chemical synthesis
10.
J Inorg Biochem ; 100(7): 1167-75, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16584779

ABSTRACT

The synthesis, characterization and comparative biological study of a series of antibacterial copper complexes with heterocyclic sulfonamides were reported. Two kinds of complexes were obtained with the stoichiometries [Cu(L)2] . H2O and [Cu(L)2(H2O)4] . nH2O. They were characterized by infrared and electronic spectroscopies and the crystal structure of [Cu(sulfisoxazole)2(H2O)4] . 2H2O was determined by single crystal X-ray diffraction. It crystallized in the C2/c with Z = 8 monoclinic space group C2/c with Z = 8. The Cu(II) is in a slightly tetragonal distorted octahedron formed by four oxygen atoms from water molecules and two nitrogen atoms from two isoxazole rings. The antimicrobial activity was evaluated for all the synthesized complexes and ligands using the agar dilution test. The results showed that the complexes with five-membered heterocyclic rings were more active than the free sulfonamides while the pyrimidine, pyridine and pyridazine complexes had similar or less activity than the free ligands. In order to find an explanation for this behavior lipophilicity and superoxide dismutase-like activity were tested, showing that the [Cu(sulfamethoxazol)2(H2O)4] . 3H2O presented the highest antimicrobial potency and a superoxide dismutase-like activity comparable with pharmacological active compounds.


Subject(s)
Copper/chemistry , Heterocyclic Compounds/chemistry , Organometallic Compounds/chemistry , Sulfacetamide/analogs & derivatives , Sulfonamides/chemistry , Superoxide Dismutase/chemical synthesis , Crystallography, X-Ray , Escherichia coli/drug effects , Microbial Sensitivity Tests , Models, Molecular , Spectrophotometry, Infrared , Staphylococcus aureus/drug effects , Sulfacetamide/chemistry , Superoxide Dismutase/chemistry , Superoxide Dismutase/pharmacology , Water/chemistry
11.
Drug Deliv ; 10(4): 283-8, 2003.
Article in English | MEDLINE | ID: mdl-14612345

ABSTRACT

The aim of this work was to encapsulate superoxide dismutase (SOD) in poly(epsilon-caprolactone) (PCL) microparticles by reverse micelle solvent evaporation. The concentration of PCL, the hydrophile-lipophile balance (HLB), and concentration of the sucrose ester used as surfactant in the organic phase were investigated as formulation variables. Relatively higher encapsulation efficiency (approximately 48%) and retained enzymatic activity (>90%) were obtained with microparticle formulation made from the 20% (w/v) PCL and 0.05% (w/v) sucrose ester of HLB = 6. This formulation allowed the in vitro release of SOD for at least 72 hr. These results showed that reverse micelle solvent evaporation can be used to efficiently encapsulate SOD in PCL microparticles. Such formulations may improve the bioavailability of SOD.


Subject(s)
Drug Compounding/methods , Micelles , Polyesters/chemical synthesis , Solvents/chemical synthesis , Superoxide Dismutase/chemical synthesis , Capsules , Polyesters/pharmacokinetics , Solvents/pharmacokinetics , Superoxide Dismutase/pharmacokinetics
12.
Free Radic Biol Med ; 24(6): 906-12, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9607600

ABSTRACT

Crosslinking hemoglobin with superoxide dismutase and catalase (PolyHb-SOD-CAT) helps to limit free radical reactivity of modified hemoglobin red blood cell substitutes. In the present study, in vitro oxidant challenge experiments were performed with exogenous hydrogen peroxide (H2O2) and xanthine oxidase-derived superoxide (O2.-). PolyHb-SOD-CAT was compared to PolyHb for the presence of secondary hemoprotein-free radical events. PolyHb-SOD-CAT prevents ferrylhemoglobin formation, measured as Na2S-induced absorbance at 620 nm. Similarly, PolyHb-SOD-CAT inhibited ferrozine-detectable iron release at high oxidant-heme ratios. The formation of oxygen radicals, monitored by salicylate hydroxylation, was prevented at high oxidant-heme ratios with PolyHb-SOD-CAT. The peroxidation of liposomal membranes was also inhibited in PolyHb-SOD-CAT mixtures subject to oxidant challenge. These results show that PolyHb-SOD-CAT prevents secondary hemoprotein-associated free radical events. This new type of modified hemoglobin oxygen carrier with antioxidant activity may reduce the potential toxicity of hemoglobin-based substitutes in certain applications, especially during reperfusion of ischemic tissues.


Subject(s)
Catalase/drug effects , Hemoglobins/drug effects , Hemoglobins/metabolism , Superoxide Dismutase/drug effects , Animals , Blood Substitutes , Catalase/chemical synthesis , Catalase/chemistry , Cattle , Cross-Linking Reagents/chemistry , Ferrozine/metabolism , Free Radical Scavengers/antagonists & inhibitors , Free Radical Scavengers/metabolism , Glutaral/chemistry , Hemoglobins/chemical synthesis , Hemoglobins/chemistry , Hydrogen Peroxide/pharmacology , Hydroxylation , Iron/analysis , Iron/metabolism , Lipid Peroxidation/drug effects , Liposomes/chemistry , Models, Biological , Oxidation-Reduction/drug effects , Phospholipids/chemistry , Salicylic Acid/analysis , Salicylic Acid/metabolism , Superoxide Dismutase/chemical synthesis , Superoxide Dismutase/chemistry , Superoxides/chemical synthesis , Superoxides/pharmacology , Xanthine Oxidase/chemistry
13.
Biochim Biophys Acta ; 998(1): 14-20, 1989 Sep 14.
Article in English | MEDLINE | ID: mdl-2790051

ABSTRACT

Three cobalt derivatives of bovine erythrocyte superoxide dismutase (superoxide:superoxide oxidoreductase, EC 1.15.1.1) have been prepared under different pH conditions using a cobalt-thiocyanate complex which has already proved to yield specific substitutions on other copper proteins. The cobalt-protein derivatives have been characterized by optical, circular dichroism and fluorescence spectroscopies. One derivative, referred to as Co2Co2-protein, contains Co(II) ions specifically bound at both Zn(II) and Cu(II) sites. On the basis of their spectroscopic properties, the other two derivatives can be referred as E2Co2- and Co2E2-superoxide dismutase, with cobalt substituting, respectively, at the zinc and the copper sites leaving the contiguous site empty (E). The Co2E2-protein complex represents a novel derivative, since it has never been described in literature. The optical spectrum in the visible region of Co2-Co2-protein well corresponds to the sum of the spectra of the other two derivatives. The circular dichroism spectrum of Co2Co2-derivative, however, is not the sum of individual E2Co2- and Co2E2-proteins, suggesting that the presence of Co(II) in one site strongly affects the geometry of the neighbouring site. Some discrepancies between our spectroscopic data and those reported in literature are discussed. The results obtained from fluorescence experiments indicate that Co(II) ions exert a different quenching effect on the tyrosine emission, depending on whether they are located in the Zn(II) or in the Cu(II) site. The fluorescence quenching can be attributed to a 'heavy atom' and 'paramagnetic ion' effect by Co(II) ions.


Subject(s)
Cobalt/blood , Erythrocytes/enzymology , Superoxide Dismutase/blood , Animals , Binding Sites , Cattle , Circular Dichroism , Copper/blood , Hydrogen-Ion Concentration , Molecular Structure , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Superoxide Dismutase/chemical synthesis , Tyrosine , Zinc/blood
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