Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P04040 (Catalase)
 3,577 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Diabetes is a multifactorial disease that has now been recognized to involve overproduction of reactive oxygen species and pro-inflammatory cytokines. Peroxisomes are subcellular organelles with several important metabolic functions, and their role in the regulation of cellular oxidative stress is now well established. Despite having their own antioxidant system, peroxisomes undergo functional alterations during various conditions that are associated with free radical production such as inflammation, ischemia-reperfusion, carcinogenesis and diabetes. In this study we investigated the effect of diabetes on peroxisomal functions in rat kidneys and show for the first time that experimental diabetes induces redox-sensitive enhancement of peroxisomal activities. Streptozotocin-induced diabetes significantly increased (p < 0.01) beta-oxidation of lignoceric acid and the enzymic activity of acyl coenzyme A oxidase. Catalase activity was significantly reduced (p < 0.01) in the kidneys of diabetic rats, whereas the enzymic activity of DHAPATase (dihydroxyacetone phosphate acyltransferase) was not markedly affected by diabetes. Treatment of diabetic rats with antioxidants, thiocetic acid and vitamin C attenuated the diabetes-induced modulation of peroxisomal functions. The present study shows that the diabetes-induced effects on kidney peroxisomal functions are redox sensitive, and antioxidants might prove useful tools to alleviate nephropathy in diabetes.
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PMID:Antioxidants attenuate diabetes-induced activation of peroxisomal functions in the rat kidney. 1531 30

Polymorphonuclear neutrophils (PMN) are thought to play a role in reperfusion injury and ischemia. These effects are partly mediated by toxic oxygen species (superoxide anion, hydrogen peroxide and hydroxyl radical) acting at the level of the endothelium. It was demonstrated recently that the superoxide anion reacts with nitric oxide (NO) and that interaction leads to the generation of highly toxic peroxynitrite. Several drugs were tested so far in order to affect PMN function. It was demonstrated that dipyridamole (2,6-bis-diethanolamino-4,8-dipiperidinopyrimido-(5,4-d)-pyrimidine) can influence neutrophil function by inhibiting adenosine uptake. However, this action can not fully explain all of the observed effects of dipyridamole action on PMN metabolism. The aim of our study was to evaluate the influence of dipyridamole on nitric oxide production by activated polymorphonuclear neutrophils. Incubation of PMNs with hydroxylamine (HA) and phorbol myristate acetate (PMA) generated nitrite (36.4+/-4.2 nmol/h 2x10(6) PMN), dipyridamole at 100 micromol/l, 50 micromol/l and 10 micromol/l caused a considerable drop in nitrite production (11.8+/-1.8, 19.7+/-2.7 and 27.4+/-3.2 nmol/h, respectively). Neither adenosine nor the adenosine analogue could mimic the dipyridamole effect. Moreover theophylline, an adenosine inhibitor could not reverse the dipirydamole action on PMN metabolism. We also found that dipyridamole inhibited hydrogen peroxide release from neutrophils. Catalase that scavenges hydrogen peroxide also largely abolished nitric oxide release from PMN. It is evident that dipyridamole inhibits hydroxylamine-augmented nitric oxide production by activated polymorphonuclear neutrophils through an adenosine-independent mechanism.
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PMID:Dipyridamole inhibits hydroxylamine augmented nitric oxide (NO) production by activated polymorphonuclear neutrophils through an adenosine-independent mechanism. 1558 33

Gene expression in frontal, occipital, and hippocampal regions of rat brains at 15 min of ischemic injury was studied in a rat model by producing focal cerebral ischemia through middle cerebral artery (MCA) occlusion without reperfusion. Catalase, epithelial glycoprotein (EGP-314), cytochrome C oxidase-subunit 1, ribosomal L31 protein, and ceruloplasmin were found to be differentially expressed. Specific primers were designed to study this newly reported brain EGP-314, a cellular adhesion molecule involved in cell-cell and cell-extracellular matrix interactions and related with cytoskeletal organization, differentiation, and proliferation. In the frontal and occipital lobes, EGP-314 expression was low in control and ischemic conditions and increased in sham injured conditions, whereas in the hippocampal region its expression was induced only by ischemia. In situ hybridization and immunohistochemistry revealed that EGP-314 mRNA and the protein were present in the ischemic hippocampus pyramidal neurons. DNA fragmentation was demonstrated by TUNEL and LM-PCR analysis in hippocampus region. TUNEL positive pyramidal neurons were observed at 15 min of ischemia. DNA ladder was found at 12 and 15 min of ischemia.
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PMID:EGP-314 is expressed differentially in three brain zones at an early time in an experimentally induced ischemia rat model. 1595 Jul 61

Reactive oxygen species (ROS) have pathogenic effects on ischemic-reperfusion injury of heart. Hence, it is important to identify natural antioxidative agents to mitigate such effects. Recently, it has been reported that Clerodendron colebrookianum (CC) leaf extract has antioxidant and hypolipidemic effects in experimental animals. The aim of this study was to examine whether acute treatment with CC extract offers protection against ischemic-reperfusion injury (IRI) and IRI-induced changes in endogenous antioxidant enzyme activities of rat heart. Isolated rat hearts were perfused using the Langendorff's technique, and 20 min of global ischemia was followed by 40 min of reperfusion. Lipid peroxidation after the ischemic-reperfusion episode was significantly reduced in the CC extract-treated heart compared to the control group and suppressed the leakage of lactate dehydrogenase (LDH) during reperfusion. Moreover, CC extract diminished the depletion of myocardial antioxidant enzymes (SOD, Catalase, GSH and GPx) after ischemia-reperfusion. Furthermore, IRI-induced cellular damage was significantly less in CC extract treated myocytes. These results indicate that CC leaf extract protects against oxidative stress and cellular injury associated with ischemic-reperfusion injury of rat heart and suggests that the protective effects of CC extract depend on its antioxidant properties.
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PMID:Extract from Clerodendron colebrookianum Walp protects rat heart against oxidative stress induced by ischemic-reperfusion injury (IRI). 1603 42

Acute cessation of flow (ischemia) leads to depolarization of the endothelial cell (EC) membrane mediated by K(ATP) channels and followed by production of reactive oxygen species (ROS) from NADPH oxidase. We postulated that ROS are a signal for initiating EC proliferation associated with the loss of shear stress. Flow cytometry was used to identify proliferating CD31-positive pulmonary microvascular endothelial cells (mPMVECs) from wild-type, Kir6.2-/-, and gp91phox-/- mice. mPMVECs were labeled with PKH26 and cultured in artificial capillaries for 72 h at 5 dyn/cm2 (flow adaptation), followed by 24 h of stop flow or continued flow. ROS production during the first hour of ischemia was markedly diminished compared with wild-type mice in both types of gene-targeted mPMVECs. Cell proliferation was defined as the proliferation index (PI). After 72 h of flow, >98% of PKH26-labeled wild-type mPMVECs were at a single peak (PI 1.0) and the proportion of cells in the S+G2/M phases were at 5.8% on the basis of cell cycle analysis. With ischemia (24 h), PI increased to 2.5 and the ratio of cells in S+G2/M phases were at 35%. Catalase, diphenyleneiodonium, and cromakalim markedly inhibited ROS production and cell proliferation in flow-adapted wild-type mPMVECs. Significant effects of ischemia were not observed in Kir6.2-/- and gp91phox-/- cells. ANG II activation of NADPH oxidase was unaffected by KATP gene deletion. Thus loss of shear stress in flow-adapted mPMVECs results in cell division associated with ROS generated by NADPH oxidase. This effect requires a functioning cell membrane KATP channel.
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PMID:Lung endothelial cell proliferation with decreased shear stress is mediated by reactive oxygen species. 1633 78

Oxygen radicals have roles in the renal ischemia-reperfusion (IR) injury usually encountered in several conditions such as renal transplantation. The aim of this study was to investigate the effects of erdosteine and N-acetylcysteine (NAC) on the oxidant/antioxidant status and microscopy of renal tissues after IR injury. Male Sprague-Dawley rats were randomly assigned to four groups: control untreated rats, IR (30 min ischemia and 120 min reperfusion), IR + NAC (i.p.; 180 mg/kg) and IR + erdosteine (oral; 50 mg/kg/day for 2 days before experiments) groups. After unilateral renal IR, the right kidney was rapidly excised and sectioned vertically into two pieces for microscopic examination and biochemical analysis. Erdosteine and NAC treatment did not cause any significant change in the activity of superoxide dismutase (SOD) in comparison with the IR group, even if the SOD activity increased in IR groups than in the control group. Catalase (CAT) activity was decreased in the IR group in comparison with control and IR + erdosteine groups (P<0.05), whereas it was higher in the IR + erdosteine group than in the IR + NAC group (P<0.05). Xanthine oxidase (XO) activity was higher in all the IR-performed groups than in the control group (P<0.05). Thiobarbituric acid-reactive substances (TBARS) level and protein carbonyl (PC) content were increased after IR injury (P<0.05). Erdosteine or NAC treatments ameliorated these increased TBARS and PC contents in comparison with the IR group (P<0.05). Light microscopy of the IR group showed tubular dilatation, tubular necrosis and vacuole formation in epithelial cells. Erdosteine but not NAC apparently reduced the renal tissue damage. The pathological damage score after IR was significantly reduced after erdosteine treatment (P<0.05), but not after NAC treatment. In conclusion, renal IR resulted in oxidative damage as seen in biochemical lipid peroxidation and protein oxidation results with aggravated tubular necrosis. Erdosteine and NAC treatments improved the biochemical results of IR injury. However, on microscopic evaluations, animals receiving erdosteine showed a great reduction in renal damage when compared with the NAC group.
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PMID:Protein oxidation and lipid peroxidation after renal ischemia-reperfusion injury: protective effects of erdosteine and N-acetylcysteine. 1642

We have recently demonstrated that endogenous H2O2 plays an important role in coronary autoregulation in vivo. However, the role of H2O2 during coronary ischemia-reperfusion (I/R) injury remains to be examined. In this study, we examined whether endogenous H2O2 also plays a protective role in coronary I/R injury in dogs in vivo. Canine subepicardial small coronary arteries (>or=100 microm) and arterioles (<100 microm) were continuously observed by an intravital microscope during coronary I/R (90/60 min) under cyclooxygenase blockade (n=50). Coronary vascular responses to endothelium-dependent vasodilators (ACh) were examined before and after I/R under the following seven conditions: control, nitric oxide (NO) synthase (NOS) inhibitor NG-monomethyl-L-arginine (L-NMMA), catalase (a decomposer of H2O2), 8-sulfophenyltheophylline (8-SPT, an adenosine receptor blocker), L-NMMA+catalase, L-NMMA+tetraethylammonium (TEA, an inhibitor of large-conductance Ca2+-sensitive potassium channels), and L-NMMA+catalase+8-SPT. Coronary I/R significantly impaired the coronary vasodilatation to ACh in both sized arteries (both P<0.01); L-NMMA reduced the small arterial vasodilatation (both P<0.01), whereas it increased (P<0.05) the ACh-induced coronary arteriolar vasodilatation associated with fluorescent H2O2 production after I/R. Catalase increased the small arterial vasodilatation (P<0.01) associated with fluorescent NO production and increased endothelial NOS expression, whereas it decreased the arteriolar response after I/R (P<0.01). L-NMMA+catalase, L-NMMA+TEA, or L-NMMA+catalase+8-SPT further decreased the coronary vasodilatation in both sized arteries (both, P<0.01). L-NMMA+catalase, L-NMMA+TEA, and L-NMMA+catalase+8-SPT significantly increased myocardial infarct area compared with the other four groups (control, L-NMMA, catalase, and 8-SPT; all, P<0.01). These results indicate that endogenous H2O2, in cooperation with NO, plays an important cardioprotective role in coronary I/R injury in vivo.
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PMID:Cardioprotective role of endogenous hydrogen peroxide during ischemia-reperfusion injury in canine coronary microcirculation in vivo. 1664 91

Ischemia-reperfusion (I/R) injury induces an inflammatory response and production of oxygen-derived reactive species which affect many organs including heart, brain, kidney and gastrointestinal tract. The aim of this study was to assess the hepatic changes after renal I/R injury. Male Sprague Dawley rats were subjected to either sham operation or treatment with L-NAME, L-arginine and BQ-123 during 30 min renal ischemia and 2 h reperfusion injury. Hepatic superoxide dismutase (SOD), catalase, glutathione peroxidase (GSH-Px) activities, and thiobarbituric acid-reactive substances (TBARS) and nitric oxide (NO) levels were evaluated to show hepatic response to renal I/R injury. Catalase and SOD activities showed significant differences between the control and the other groups after I/R. On the other hand, GSH-Px activity did not show any significant changes between the control and the other experimental groups mentioned under above conditions. Meanwhile, levels of TBARS were not different between the control and the other experimental groups, whereas NO level showed changes between the control and experimental groups except the one to which endothelin receptor antagonist agent (BQ-123) subjected. Experimental period may not be enough to determine the changes in GSH-Px activity and level of TBARS. However, catalase and SOD activities decreased in experimental groups treated by chemical agents. NO level decreased in chemicalagent-applied experimental groups but not in the group to which endothelin receptor antagonist BQ-123 was applied alone.
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PMID:Effect of BQ-123 and nitric oxide inhibition on liver in rats after renal ischemia-reperfusion injury. 1691 32

Exercise provides cardioprotection against ischemia-reperfusion injury, a process involving mitochondrial reactive oxygen species (ROS) generation and calcium overload. This study tested the hypotheses that isolated mitochondria from hearts of endurance-trained rats have decreased ROS production and improved tolerance against Ca(2+)-induced dysfunction. Male Fischer 344 rats were either sedentary (Sed, n = 8) or endurance exercise trained (ET, n = 11) by running on a treadmill for 16 wk (5 days/wk, 60 min/day, 25 m/min, 6 degrees grade). Mitochondrial oxidative phosphorylation measures were determined with glutamate-malate or succinate as substrates, and H(2)O(2) production and permeability transition pore (PTP) opening were determined with succinate. All assays were carried out in the absence and presence of calcium. In response to 25 and 50 microM CaCl(2), Sed and ET displayed similar decreases in state 3 respiration, respiratory control ratio, and ADP:O ratio. Ca(2+)-induced PTP opening was also similar. However, H(2)O(2) production by ET was lower than Sed (P < 0.05) in the absence of calcium (323 +/- 12 vs. 362 +/- 11 pmol.min(-1).mg protein(-1)) and the presence of 50 microM CaCl(2) (154 +/- 3 vs. 197 +/- 7 pmol.min(-1).mg protein(-1)). Rotenone, which blocks electron flow from succinate to complex 1, reduced H(2)O(2) production and eliminated differences between ET and Sed. Mitochondrial superoxide dismutase and glutathione peroxidase were not affected by exercise. Catalase activity was extremely low but increased 49% in ET (P < 0.05). In conclusion, exercise reduces ROS production in myocardial mitochondria through adaptations specific to complex 1 but does not improve mitochondrial tolerance to calcium overload.
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PMID:Exercise training decreases rat heart mitochondria free radical generation but does not prevent Ca2+-induced dysfunction. 1730 8

Excessive generation of free radicals and decreased levels of the antioxidant enzymes such as superoxide dismutase (SOD) and catalase have been observed after brain ischemic reperfusion injury. In the present study, we have investigated the neuroprotective potential of MnTMPyP (Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin pentachloride), a SOD/Catalase mimetic in bilateral carotid artery occlusion model of global cerebral ischemia in Mongolian gerbils. Five minutes of bilateral carotid artery occlusion produced global cerebral ischemia, which was evident from the neurological deficits, spontaneous motor activity and the decrease in the number of viable hippocampal CA1 neurons. Global ischemia was also associated with increased levels of malondialdehyde, decreased levels of SOD and catalase, and increased TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) positive cells, indicating oxidative stress and DNA fragmentation. Administration of a single dose of MnTMPyP, 1 mg/kg i.p. (30 min before occlusion), produced no significant neuroprotection; however, 3 mg/kg i.p. (30 min before to occlusion) produced significant reduction in neurological score, spontaneous motor activity and CA1 pyramidal neuronal damage. MnTMPyP also attenuated the increased levels of malondialdehyde and improved the levels of SOD and catalase, and inhibited DNA fragmentation in the ischemic animals. Multiple administration of MnTMPyP, 3 mg/kg i.p. (three times: 30 min before, 1 h and 3 h after occlusion), produced better neuroprotection as compared to single dose administration. This study demonstrates that the neuroprotective effect of MnTMPyP in global ischemia is mediated through reduction in oxidative stress and DNA fragmentation.
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PMID:Neuroprotective effect of MnTMPyP, a superoxide dismutase/catalase mimetic in global cerebral ischemia is mediated through reduction of oxidative stress and DNA fragmentation. 1732 Aug 58


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