Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P30044 (antioxidant enzyme)
 8,037 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Animal models and human studies have shown that conjugated dienes rise in the plasma after thermal injury. These dienes may serve as a marker of oxygen radical-mediated tissue injury. Twelve burn patients were randomized to receive the antioxidant enzyme polyethylene glycol-conjugated superoxide dismutase (PEG-SOD). Patients received either 500 or 1000 units per kilogram of PEG-SOD intravenously within 6 h of injury. Plasma samples were collected and conjugated diene levels were compared to diene levels of burn patients not treated and to diene levels from normal volunteers. Conjugated diene levels were increased in burn patients. PEG-SOD in either dose initially decreased conjugated diene levels in the plasma of both treatment groups. By 72 h, the diene levels increased in the 500 unit/kg group, but remained at near control levels in the 1000 unit/kg group for up to 200 h after injury. These data suggest that PEG-SOD is capable of preventing conjugated dienes formed as the result of oxygen radical production. It appears that 1000 units/kg is more effective than 500 units/kg in preventing conjugated diene formation.
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PMID:Superoxide dismutase prevents lipid peroxidation in burned patients. 207 36

The 27-day-old rat exposed to 100% oxygen (O2) for 8 days will have predictable lung vascular and parenchymal changes at 60 days of age. Using this model, the goals of this study are (1) to measure the lung antioxidant enzyme activities serially following intratracheal PEG antioxidant therapy during the 8-day O2 exposure; and (2) to assess chronic cardiopulmonary changes in the O2-exposed rats treated with PEG-CAT and/or PEG-CuZn SOD given intraperitoneally (IP) and/or intratracheally (IT). The study encompassed 202 male rats exposed to room air or oxygen. CuZn SOD doses were 300 U IT and 2000 U IP. The CAT dose was 500 or 4000 U IT and 10,000 U IP. At 60 days of age, the right ventricular systolic pressure (RVP), RV weight, % acinar wall arterial thickness, and parenchymal air space were significantly increased in O2-exposed rats compared to RA rats. The RVP, RV weight, and parenchymal changes were prevented by daily IT PEG-CAT 4000 U + CuZn SOD 300 U but the increased small artery muscularization was not. Three hours after the initial dose of IT PEG-CAT 4000 U, lung CAT activity was more than doubled and remained constant throughout the 8-day daily treatment course. This dose of CAT depressed the induction response to O2 of CuZn and MnSOD. It is concluded that daily intratracheal administration of PEG-CAT 4000 U + CuZn SOD 300 U can significantly ameliorate some of the chronic parenchymal and vascular lung O2 toxic changes. However, it appears that high-dose exogenous PEG-CAT suppresses the endogenous enzyme induction to hyperoxia of both CuZn and Mn-SOD.
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PMID:Lung antioxidant enzymes and cardiopulmonary responses in young rats exposed to hyperoxia and treated intratracheally with PEG catalase and superoxide dismutase. 846 59

We investigated the effect of hemorrhagic shock and reinfusion on the cardiac function and contractility, plasma CK and CK-MB activity and lactate concentration, oxyradical-producing activity of polymorphonuclear leukocytes (PMNL-CL), cardiac chemiluminescence (LV-CL), antioxidant enzyme activity [superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-PX)] and malondialdehyde (MDA) concentration in anesthetized dogs to determine the role of oxyradicals in cardiac depression and cellular injury in hemorrhagic shock and reinfusion. The dogs were assigned into three groups: I (sham), 4 h duration; II (S + R), 2 h of shock followed by reinfusion for 2 h; III (SOD + S + R), as II but pretreated with PEG-SOD. Hemorrhagic shock was produced by withdrawal of blood to maintain the mean arterial pressure at 50 +/- 5 mm Hg. Cardiac function and contractility were depressed during hemorrhagic shock. Plasma CK, CK-MB and lactate increased during shock. Following reinfusion after 2 h of shock hemodynamic parameters and plasma lactate tended to return towards control values. Plasma CK and CK-MB, PMNL-CL and cardiac MDA, total-, Mn- and CuZn-SOD activity increased while LV-CL decreased. In spite of the increase in the antioxidant reserve, there was oxidative damage. Pretreatment with SOD attenuated the deleterious effects of shock and reinfusion on the cardiovascular function, plasma CK, and CK-MB, PMNL-CL, cardiac MDA, SOD, and LV-CL. Protection was incomplete for cardiovascular function and plasma CK and CK-MB. These results suggest that oxyradicals may partly be involved in the deterioration of cardiovascular function and cellular injury during hemorrhagic shock and reinfusion.
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PMID:Cardiac depression and cellular injury in hemorrhagic shock and reinfusion: role of free radicals. 940 75

HORF6 is a member of the novel antioxidant enzyme family found in humans. A recombinant form of hORF6 expressed and purified from E. coli has been crystallized by the hanging-drop method using various PEG's as precipitating agents. HORF6 crystallizes in two different monoclinic space groups, P21 and C2. The P21 crystals have unit-cell dimensions of a = 47.85, b = 75.17, c = 63.30 A and beta = 110.21 degrees and contain two monomers per asymmetric unit, while the C2 crystals have unit-cell dimensions of a = 165.27, b = 95.44, c = 166.44 A and beta = 128.97 degrees and contain more than six monomers per asymmetric unit. The P21 crystals with the smaller unit cell diffract X-rays better and behave well for the X-ray analysis. A native data set from a single crystal of the P21 space group gas been collected to 2.0 A resolution.
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PMID:Crystallization and preliminary X-ray studies of hORF6, a novel human antioxidant enzyme. 976 20

Mycobacterium tuberculosis (H37Rv), the causative agent of the dreaded disease tuberculosis, contains three thioredoxins and a single thioredoxin reductase. Thioredoxin reductase is a member of the pyridine-nucleotide disulfide oxidoreductase family of flavoenzymes. The thioredoxin reductase gene with a His tag at the C-terminus was expressed in Escherichia coli and purified. The dimeric (70 kDa) protein was incubated with 10 mM DTT for 30 min and then crystallized using the hanging-drop vapour-diffusion method in the presence of 15% PEG 3350 and phosphate-citrate buffer pH 5 at room temperature (298 K). A diffraction data set complete to 3 A resolution has been collected under cryoconditions and the space group was determined to be P4(1)2(1)2, with unit-cell parameters a = 107.4, c = 118.2 A. Matthews coefficient calculations revealed the presence of two monomers in the asymmetric unit.
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PMID:Expression, purification, crystallization and preliminary X-ray crystallographic studies of Mycobacterium tuberculosis thioredoxin reductase. 1503 84

Polymeric nanocarriers (PNCs), proposed as an attractive vehicle for vascular drug delivery, remain an orphan technology for enzyme therapies due to poor loading and inactivation of protein cargoes. To unite enzyme delivery by PNC with a clinically relevant goal of containment of vascular oxidative stress, a novel freeze-thaw encapsulation strategy was designed and provides approximately 20% efficiency loading of an active large antioxidant enzyme, catalase, into PNC (200-300 nm) composed of biodegradable block copolymers poly(ethylene glycol)-b-poly(lactic-glycolic acid). Catalase's substrate, H(2)O(2), was freely diffusible in the PNC polymer. Furthermore, PNC-loaded catalase stably retained 25-30% of H(2)O(2)-degrading activity for at least 18 h in a proteolytic environment, while free catalase lost activity within 1 h. Delivery and protection of catalase from lysosomal degradation afforded by PNC nanotechnology may advance effectiveness and duration of treatment of diverse disease conditions associated with vascular oxidative stress.
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PMID:Polymer nanocarriers protecting active enzyme cargo against proteolysis. 1565 62

The aim of this study was to test the effect of L: -arginine methyl ester (L-Arg) on indices of free radical involvement in a rat model of experimental nephrocalcinosis. Twenty-eight Sprague-Dawley rats were randomized into four groups of seven. The first group (G1), the sham-control group received pure distilled drinking water. The second group (G2) received drinking water containing 0.7% ethylene glycol (EG) in distilled water for 3 weeks. The third group (G3) received drinking water containing 0.7% EG in distilled water for 3 weeks and L-Arg was administered for 3 weeks. The fourth group (G4) received drinking water containing 0.7% EG in distilled water for 3 weeks and L-NAME was administered for 3 weeks. Urine and aortic blood was collected to determine some parameters. The kidneys were also removed for histological examination. The increase in blood urea nitrogen, serum creatinine, K(+), Mg(2+ )and uric acid were mild in group 3 compared with the groups 2 and 4. The urinary concentrations of Na(+), K(+), Mg(2+) and uric acid were noticed to be similar among the groups. However, Ca(2+ )and oxalate excretion were significantly higher in groups 2, 3 and 4 than in group 1. The mean values of SOD, CAT and GSH-Px values were significantly increased in group 3 when compared to groups 2 and 4. Presence of aggregated urinary crystals was clearer in experimental groups compared to group 1. The tubular dilatation, epithelial degeneration and lymphocytic infiltration were significantly found in groups 2 and 4. Mild tissue damage was observed in L-Arg-pretreated rats. Under polarized light microscope intense crystals in the cortex and medulla were observed in the kidney of group 2 and 4 and moderate crystals were noticed in group 3. In conclusion, L-Arg supplementation may decrease free radicals and tubulary membrane injury in nephrocalcinosis due to infiltrating leukocytes and decreased antioxidant enzyme activities in rats fed with EG diet.
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PMID:The effect of L-arginine methyl ester on indices of free radical involvement in a rat model of experimental nephrocalcinosis. 1682 49

Deinococcus radiodurans, a Gram-positive bacterium capable of withstanding extreme ionizing radiation, contains two thioredoxins (Trx and Trx1) and a single thioredoxin reductase (TrxR) as part of its response to oxidative stress. Thioredoxin reductase is a member of the family of pyridine nucleotide-disulfide oxidoreductase flavoenzymes. Recombinant D. radiodurans TrxR with a His tag at the N-terminus was expressed in Escherichia coli and purified by metal-affinity chromatography. The protein was crystallized using the sitting-drop vapour-diffusion method in the presence of 35% PEG 4000, 0.2 M ammonium acetate and citric acid buffer pH 5.1 at 293 K. X-ray diffraction data were collected on a cryocooled crystal to a resolution of 1.9 angstroms using a synchrotron-radiation source. The space group was determined to be P3(2)21, with unit-cell parameters a = b = 84.33, c = 159.88 angstroms. The structure of the enzyme has been solved by molecular-replacement methods and structure refinement is in progress.
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PMID:Expression, purification, crystallization and preliminary X-ray crystallographic studies of Deinococcus radiodurans thioredoxin reductase. 1688 May 49

Superoxide dismutase (SOD) is the most potent antioxidant enzyme. In this study, SOD was encapsulated in chitosan microspheres to obtain suitable sustained protein delivery. Protein-loaded chitosan microspheres with various formulations were prepared based on complex coacervation process. Due to the inherent characteristic of SOD, high encapsulation efficiency could not be obtained with simple preparation method. The pH of chitosan solution is 3.0; when the chitosan microspheres were prepared with this solution, encapsulation was low. Therefore, several strategies have been tested to increase the encapsulation efficiency and good results have been obtained. 70-80% protein encapsulation efficiency was obtained. The addition of PEG to the protein solution enhanced the encapsulation efficiency also. Mean sizes of microspheres were between 1.38 and 1.94 microm. Factors affecting the release behaviour of SOD from microspheres have been studied. They included pH values of chitosan solution (the pH of chitosan solution is 3.0), addition of PEG to the protein solution and the use of adsorption technique. In general, biphasic release profiles were obtained with these formulations. The protein activity changed between 70 and 100% during the release. In general, the protein activity remained in acceptable limits. The SOD encapsulated chitosan microspheres can be prepared by changing the pH or addition of PEG, allowing the safe incorporation of protein for controlled release.
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PMID:Preparation of superoxide dismutase loaded chitosan microspheres: characterization and release studies. 1705 12

Rapid clearance and proteolysis limit delivery and efficacy of protein therapeutics. Loading into biodegradable polymer nanocarriers (PNC) might protect proteins, extending therapeutic duration, but loading can be complicated by protein unfolding and inactivation. We encapsulated active enzymes into methoxy-poly(ethylene glycol- block-lactic acid) (mPEG-PLA) PNC with a freeze-thaw double emulsion ( J. Controlled Release 2005, 102 (2), 427-439). On the basis of concepts of amphiphile self-assembly, we hypothesized that the copolymer block ratio that controls spontaneous curvature would influence PNC morphology and loading. We examined PNC yield, shape, stability, loading, activity, and protease resistance of the antioxidant enzyme, catalase. PNC transitioned from spherical to filamentous shapes with increasing hydrophobic polymer fraction, consistent with trends for self-assembly of lower MW amphiphiles. Importantly, one diblock copolymer formed filamentous particles loaded with significant levels of protease-resistant enzyme, demonstrating for the first time encapsulation of an active therapeutic enzyme into filamentous carriers. PNC morphology also greatly influenced its degradation, offering a new means of controlled delivery.
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PMID:Effect of polymer amphiphilicity on loading of a therapeutic enzyme into protective filamentous and spherical polymer nanocarriers. 1803 99


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