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)

Bcl-2 is a gene family involved in the suppression of apoptosis in response to a wide range of cellular insults. Multiple papers have suggested a link between Bcl-2 and oxidative damage/antioxidant protection. We therefore examined parameters of antioxidant defense and oxidative damage in two different cell lines, NT-2/D1 (NT-2) and SK-N-MC, overexpressing Bcl-2 as compared with vector-only controls. Bcl-2 transfectants of both cell lines were more resistant to H(2)O(2) and showed increases in GSH level and Cu/Zn-superoxide dismutase (SOD1) activity, but not in Mn-superoxide dismutase, glutathione peroxidase, or glutathione reductase activities. Catalase activity was increased in SK-N-MC cells. Overexpression of Bcl-2 did not significantly decrease levels of oxidative DNA damage (measured as 8-hydroxyguanine) or lipid peroxidation, but it decreased levels of 3-nitrotyrosine in both cell lines and protein carbonyls in SK-N-MC cells only. It also increased proteasome activity in both cell lines. We conclude that Bcl-2 raises cellular antioxidant defense status, but this is not necessarily reflected in decreased levels of oxidative damage to DNA and lipids. The ability of Bcl-2 overexpression to decrease 3-nitrotyrosine levels suggests that it may decrease formation of peroxynitrite or other reactive nitrogen species; this was confirmed as decreased production of NO(2)(-)/NO(3)(-) in the transfected cells and a fall in the level of nNOS protein.
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PMID:Effect of overexpression of BCL-2 on cellular oxidative damage, nitric oxide production, antioxidant defenses, and the proteasome. 1174 29

Primary trauma to the spinal cord triggers a cascade of cellular and molecular events that promote continued tissue damage and expansion of the lesion for extended periods following the initial injury. Oxidative and nitrosative stresses play an important role in progression of spinal cord injury (SCI). In an attempt to explore the biochemical origin of oxidative/nitrosative stress associated with secondary SCI, we studied expression of the superoxide (O2*-)-generating enzyme, NAD(P)H oxidase, antioxidant enzymes [superoxide dismutase (CuZn SOD, Mn SOD), catalase, glutathione peroxidase (GPX)], nitric oxide synthases (NOS) and a byproduct of NO-O2*- interaction (nitrotyrosine) in the spinal cord tissues of rats 16 h and 14 days after surgical resections of a 5-mm segment of the cord below T8 or sham-operation. Immunodetectable NAD(P)H oxidase subunits (gp91phox and P67phox), Mn SOD, inducible NOS (iNOS), endothelial NOS (eNOS), and nitrotyrosine were elevated in the transected cords on day 1 and day 14. Neuronal NOS (nNOS) was unchanged on day 1 and significantly depressed on day 14. GPX was unchanged on day 1 and significantly elevated on day 14. Catalase was unchanged in the cord tissue surrounding the transection site at both points. Thus, concurrent upregulations of NAD(P)H oxidase, eNOS and iNOS (but not nNOS), work in concert to maintain oxidative and nitrosative stress in the injured cord tissue.
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PMID:NAD(P)H oxidase, superoxide dismutase, catalase, glutathione peroxidase and nitric oxide synthase expression in subacute spinal cord injury. 1464 73

Although neuronal nitric oxide synthase (nNOS) plays a substantial role in skeletal muscle physiology, nNOS-knockout mice manifest an only mild phenotypic malfunction in this tissue. To identify proteins that might be involved in adaptive responses in skeletal muscle of knockout mice lacking nNOS, 2D-PAGE with silver-staining and subsequent tandem mass spectrometry (LC-MS/MS) was performed using extracts of extensor digitorum longus muscle (EDL) derived from nNOS-knockout mice in comparison to C57Bl/6 control mice. Six proteins were significantly (P < or = 0.05) more highly expressed in EDL of nNOS-knockout mice than in that of C57 control mice, all of which are involved in the metabolism of reactive oxygen species (ROS). These included prohibitin (2.0-fold increase), peroxiredoxin-3 (1.9-fold increase), Cu(2+)/Zn(2+)-dependent superoxide dismutase (SOD; 1.9-fold increase), heat shock protein beta-1 (HSP25; 1.7-fold increase) and nucleoside diphosphate kinase B (2.6-fold increase). A significantly higher expression (4.1-fold increase) and a pI shift from 6.5 to 5.9 of peroxiredoxin-6 in the EDL of nNOS-knockout mice were confirmed by quantitative immunoblotting. The concentrations of the mRNA encoding five of these proteins (the exception being prohibitin) were likewise significantly (P < or = 0.05) higher in the EDL of nNOS-knockout mice. A higher intrinsic hydrogen peroxidase activity (P < or = 0.05) was demonstrated in EDL of nNOS-knockout mice than C57 control mice, which was related to the presence of peroxiredoxin-6. The treatment of mice with the chemical NOS inhibitor L-NAME for 3 days induced a significant 3.4-fold up-regulation of peroxiredoxin-6 in the EDL of C57 control mice (P < or = 0.05), but did not alter its expression in EDL of nNOS-knockout mice. ESR spectrometry demonstrated the levels of superoxide to be 2.5-times higher (P < or = 0.05) in EDL of nNOS-knockout mice than in C57 control mice while an in vitro assay based on the emission of 2,7-dichlorofluorescein fluorescence disclosed the concentration of ROS to be similar in both strains of mice. We suggest that the up-regulation of proteins that are implicated in the metabolism of ROS, particularly of peroxiredoxin-6, within skeletal muscles of nNOS-knockout mice functionally compensates for the absence of nNOS in scavenging of superoxide.
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PMID:Up-regulation of the peroxiredoxin-6 related metabolism of reactive oxygen species in skeletal muscle of mice lacking neuronal nitric oxide synthase. 1904

In large vessels, endothelium-dependent vasodilation is mainly attributed to endothelial nitric oxide synthase (eNOS)-derived NO production. However, we have recently shown that neuronal nitric oxide synthase (nNOS)-derived H(2)O(2) is also an endothelium-dependent relaxing factor in the mouse aorta. The relative contribution of nNOS/eNOS, H(2)O(2)/NO remains to be characterized. This work was undertaken to determine the relative contribution of NO versus H(2)O(2), and eNOS versus nNOS to endothelium-dependent vasodilation in the mouse aorta. We used carbon microsensors placed next to the lumen of the vessels to simultaneously measure NO, H(2)O(2) and vascular tone. Acetylcholine produced a concentration-dependent increase in NO and H(2)O(2) production with a good coefficient of linearity with acetylcholine-induced relaxation (R(2)=0.93 and 0.96 for NO and H(2)O(2), respectively). L-NAME, a non-selective inhibitor of nitric oxide synthase, abolished NO and H(2)O(2) production, and impaired vasodilation. Selective pharmacological inhibition of nNOS with L-Arg(NO2)-L-Dbu-NH(2) 2TFA and specific knock-down of nNOS abrogated H(2)O(2) and decreased by half acetylcholine-induced vasodilation. Catalase, which specifically decomposes H(2)O(2), did not interfere with NO, but impaired H(2)O(2) and decreased vasodilation to the same level as those obtained with nNOS inhibition or knocking down. Specific knocking down of eNOS had no effect on H(2)O(2) production but greatly reduced NO and decreased vasodilation to levels similar to those found with nNOS inhibition. In eNOS knocked-down mice, pharmacological nNOS inhibition dramatically reduced H(2)O(2) production and further reduced the residual acetylcholine-induced vasodilation. It is concluded that nNOS/eNOS and H(2)O(2)/NO both contribute in a significant way to relaxation in the mouse aorta.
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PMID:Relative contribution of eNOS and nNOS to endothelium-dependent vasodilation in the mouse aorta. 2062 83