Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
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Target Concepts:
Gene/Protein
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Query: EC:1.6.3.1 (
NADPH oxidase
)
11,281
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
A degree of brain inflammation is required for repair of damaged tissue, but excessive inflammation causes neuronal cell death. Here, we observe that IL-10 is expressed in LPS-injected rat cerebral cortex, contributing to neuronal survival. Cells immunopositive for IL-10 were detected as early as 8 h post-injection and persisted for up to 3 d, in parallel with the expression of IL-1beta,
TNF-alpha
, and iNOS. Double immunofluorescence staining showed that IL-10 expression was localized mainly in activated microglia. Next, we examined the neuroprotective effects of IL-10 using IL-10 neutralizing antibody (IL-10NA). Blockade of IL-10 action caused a significant loss of neurons both 3 d and 7 d after LPS injection. Further, the induction of mRNA species encoding IL-1beta,
TNF-alpha
, and iNOS, reactive oxygen species (ROS) production, and
NADPH oxidase
activation, increased after co-injection of LPS and IL-10NA, compared to the levels seen after injection of LPS alone. Taken together, these results clearly suggest that LPS-induced endogenous expression of IL-10 in microglia contributes to neuronal survival by inhibiting brain inflammation.
...
PMID:Interleukin-10 endogenously expressed in microglia prevents lipopolysaccharide-induced neurodegeneration in the rat cerebral cortex in vivo. 1816 Aug 52
Mammalian sterile 20-kinase 1 (Mst1), a member of the sterile-20 family protein kinase, plays an important role in the induction of apoptosis. However, little is know about the physiological activator of Mst1 and the role of Mst1 in endothelial cells (ECs). We examined whether Mst1 is involved in the tumor necrosis factor (TNF)-alpha-induced apoptosis of ECs. Western blot analysis revealed that
TNF-alpha
induced activation of caspase 3 and Mst1 in a time- and dose-dependent manner.
TNF-alpha
-induced Mst1 activation is almost completely prevented by pretreatment with Z-DEVD-FMK, a caspase 3 inhibitor. Nuclear staining with Hoechst 33258 and fluorescence-activated cell sorting of propidium iodide-stained cells showed that
TNF-alpha
induced apoptosis of EC. Diphenyleneiodonium, an inhibitor of
NADPH oxidase
, and N-acetylcysteine, a potent antioxidant, also inhibited
TNF-alpha
-induced activation of Mst1 and caspase 3, as well as apoptosis. Knockdown of Mst1 expression by short interfering RNA attenuated
TNF-alpha
-induced apoptosis but not cleavage of caspase 3. These results suggest that Mst1 plays an important role in the induction of
TNF-alpha
-induced apoptosis of EC. However, positive feedback mechanism between Mst1 and caspase 3, which was shown in the previous studies, was not observed. Inhibition of Mst1 function may be beneficial for maintaining the endothelial integrity and inhibition of atherogenesis.
...
PMID:Involvement of Mst1 in tumor necrosis factor-alpha-induced apoptosis of endothelial cells. 1818 60
Previously we have shown that both Rac1 and c-Jun NH(2)-terminal kinase (JNK1/2) are key proapoptotic molecules in tumor necrosis factor (TNF)-alpha/cycloheximide (CHX)-induced apoptosis in intestinal epithelial cells, whereas the role of reactive oxygen species (ROS) in apoptosis is unclear. The present studies tested the hypothesis that Rac1-mediated ROS production is involved in
TNF-alpha
-induced apoptosis. In this study, we showed that
TNF-alpha
/CHX-induced ROS production and hydrogen peroxide (H(2)O(2))-induced oxidative stress increased apoptosis. Inhibition of Rac1 by a specific inhibitor NSC23766 prevented
TNF-alpha
-induced ROS production. The antioxidant, N-acetylcysteine (NAC), or rotenone (Rot), the mitochondrial electron transport chain inhibitor, attenuated mitochondrial ROS production and apoptosis. Rot also prevented JNK1/2 activation during apoptosis. Inhibition of Rac1 by expression of dominant negative Rac1 decreased
TNF-alpha
-induced mitochondrial ROS production. Moreover,
TNF-alpha
-induced cytosolic ROS production was inhibited by Rac1 inhibition, diphenyleneiodonium (DPI, an inhibitor of
NADPH oxidase
), and NAC. In addition, DPI inhibited
TNF-alpha
-induced apoptosis as judged by morphological changes, DNA fragmentation, and JNK1/2 activation. Mitochondrial membrane potential change is Rac1 or cytosolic ROS dependent. Lastly, all ROS inhibitors inhibited caspase-3 activity. Thus these results indicate that
TNF-alpha
-induced apoptosis requires Rac1-dependent ROS production in intestinal epithelial cells.
...
PMID:TNF-alpha/cycloheximide-induced apoptosis in intestinal epithelial cells requires Rac1-regulated reactive oxygen species. 1821 73
In this paper we report that diphenyliodonium (DPI), a
NADPH oxidase
inhibitor, shows potent anti-inflammatory and neuroprotective effects at femtomolar concentrations (10(-13) to 10(-14) M) in primary midbrain cultures. Mechanistic studies revealed that DPI-elicited effects were mediated by the inhibition of LPS-induced microglial ROS production and the subsequent release of pro-inflammatory cytokine
TNFa
, and the production of nitric oxide. Further studies showed that 10(-14) M DPI significantly reduced LPS-induced ERK phosphorylation. Taken together, our results demonstrate that femtomolar concentrations of DPI exert potent anti-inflammatory and neuroprotective effects by inhibiting microglial activation through the inhibition of ERK-regulated PHOX activity.
...
PMID:NADPH oxidase inhibitor DPI is neuroprotective at femtomolar concentrations through inhibition of microglia over-activation. 1826 57
Oxidative stress and inflammation processes are key components of atherosclerosis, from fatty streak formation to plaque rupture and thrombosis. Evidence has revealed that calcium-channel blockers (CCB) could retard atherogenesis, but the exact mechanisms have not been fully elucidated. The present study was undertaken to investigate the potential effects and molecular mechanisms of the CCB felodipine on the process of atherosclerosis in high-cholesterol-diet (HCD) apolipoprotein E-knockout (ApoE KO) mice. Adult male ApoE KO mice were given a normal diet (ND) or HCD and were randomized to no treatment or felodipine (5 mg / kg per day for 12 weeks). The ApoE KO mice with HCD were associated with a marked increase in plasma lipid levels, atherosclerotic lesion area, and the expressions of
NADPH oxidase
subunits (p47 and Rac-1), nuclear factor-kappaB (NF-kappaB) in nucleus, phosphor-inhibitors of kappaB (p-IkappaB), tumor necrosis-alpha (
TNF-alpha
), monocyte chemoattractant protein-1 (MCP-1), and vascular cell-adhesion molecule-1 (VCAM-1). These changes were suppressed in mice that were treated with felodipine (5 mg/kg per day for 12 weeks) concomitant with HCD administration, with no significant change in systolic blood pressure and plasma lipid levels. The results suggest that felodipine can attenuate atherosclerosis, and this effect is partly related to inhibition of oxidative stress and inflammatory signal-transduction pathways, which lead to decreases in the expression of inflammatory cytokines.
...
PMID:Molecular mechanisms of felodipine suppressing atherosclerosis in high-cholesterol-diet apolipoprotein E-knockout mice. 1828 87
Recent studies have reported that the cholinergic anti-inflammatory pathway regulates peripheral inflammatory responses via alpha7 nicotinic acetylcholine receptors (alpha7 nAChRs) and that acetylcholine and nicotine regulate the expression of proinflammatory mediators such as
TNF-alpha
and prostaglandin E2 in microglial cultures. In a previous study we showed that ATP released by beta-amyloid-stimulated microglia induced reactive oxygen species (ROS) production, in a process involving the P2X(7) receptor (P2X(7)R), in an autocrine fashion. These observations led us to investigate whether stimulation by nicotine could regulate fibrillar beta amyloid peptide (1-42) (fAbeta1-42)-induced ROS production by modulating ATP efflux-mediated Ca(2+) influx through P2X(7)R. Nicotine inhibited ROS generation in fAbeta(1-42)-stimulated microglial cells, and this inhibition was blocked by mecamylamine, a non-selective nAChR antagonist, and a-bungarotoxin, a selective alpha7 nAChR antagonist. Nicotine inhibited
NADPH oxidase
activation and completely blocked Ca(2+) influx in fAbeta(1-42)-stimulated microglia. Moreover, ATP release from fAbeta(1-42)-stimulated microglia was significantly suppressed by nicotine treatment. In contrast, nicotine did not inhibit 2',3'-O-(4-benzoyl)-benzoyl ATP (BzATP)-induced Ca(2+) influx, but inhibited ROS generation in BzATP-stimulated microglia, indicating an inhibitory effect of nicotine on a signaling process downstream of P2X(7)R. Taken together, these results suggest that the inhibitory effect of nicotine on ROS production in fAbeta1-42-stimulated microglia is mediated by indirect blockage of ATP release and by directly altering the signaling process downstream from P2X(7)R.
...
PMID:Activation of nicotinic acetylcholine receptor prevents the production of reactive oxygen species in fibrillar beta amyloid peptide (1-42)-stimulated microglia. 1830 93
A growing body of evidence suggests oxidative stress involvement in neurodegenerative diseases; however, it remains to be determined whether oxidative stress is a cause, result, or epiphenomenon of the pathological processes. This review concerns the current issue, focusing on Alzheimer disease (AD), Parkinson disease (PD), and amyotrophic lateral sclerosis (ALS). Several studies have indicated that oxidative stress initially occurs in the disease-specific, site-restricted sources such as amyloid-beta in the cerebral cortex of AD brain, alpha-synuclein in the brain stem of PD brain, and glutamate receptor-coupled Ca2+ channel in the motor system of ALS spinal cord. Subsequent events in the neurons common to these diseases are glutamate-induced neurotoxicity and increased cytosolic Ca2+ levels, resulting in activation of Ca2+ -dependent enzymes including
NADPH oxidase
, cytosolic phospholipase A2, xanthine oxidase, and neuronal nitric oxide synthase (NOS). These enzymes produce reactive oxygen and nitrogen species (ROS/RNS), which oxidatively modify nucleic acid, lipid, sugar, and protein, leading to nuclear damage, mitochondrial damage, proteasome inhibition, and endoplasmic reticulum (ER) stress. Mitochondrial damage results in both ROS leakage from the electron transport system and Ca2+ release. Nuclear damage induces p53 activation, and proteasome inhibition reduces p53 degradation. The resultant increased p53 levels in the nucleus induce Bax activation and Bcl-2 inhibition, followed by a release of cytochrome c into the cytosol that truncates procaspase-9. ER stress triggers activation of caspase-12 as well as caspase-9 via the tumor necrosis factor (TNF) receptor-associated factor-2 / apoptosis-signaling kinase-1 / c-Jun N-terminal kinase pathway. Oxidative stress also stimulates astrocytes and microglia to yield and secrete cytokines such as
TNFa
and FasL that cause not only neuronal caspase-8 activation but also glial inflammatory response through induction of nuclear factor-kappaB-mediated, proinflammatory gene products including cytokines, chemokines, growth factors, cell adhesion molecules, and ROS/RNS-producing enzymes. The activated caspases truncate procaspase-3 to exert classical apoptosis. Moreover, oxidative DNA damage leads to the release and nuclear truncation of mitochondrial apoptosis-inducing kinase, which triggers apoptosis-like programmed cell death via cyclophilin A. These observations could indicate crucial implications for oxidative stress in several steps of the pathomechanisms of neurodegenerative diseases.
...
PMID:[The role for oxidative stress in neurodegenerative diseases]. 1830 64
Intermittent hypoxia due to sleep apnea syndrome is associated with cardiovascular diseases. However, the precise mechanisms by which intermittent hypoxic stress accelerates cardiovascular diseases are largely unclear. The aim of this study was to investigate the role of gp91(phox)-containing
NADPH oxidase
in the development of left ventricular (LV) remodeling induced by intermittent hypoxic stress in mice. Male gp91(phox)-deficient (gp91(-/-)) mice (n = 26) and wild-type (n = 39) mice at 7-12 wk of age were exposed to intermittent hypoxia (30 s of 4.5-5.5% O(2) followed by 30 s of 21% O(2) for 8 h/day during daytime) or normoxia for 10 days. Mean blood pressure and LV systolic and diastolic function were not changed by intermittent hypoxia in wild-type or gp91(-/-) mice, although right ventricular systolic pressure tended to be increased. In wild-type mice, intermittent hypoxic stress significantly increased the diameter of cardiomyocytes and interstitial fibrosis in LV myocardium. Furthermore, intermittent hypoxic stress increased superoxide production, 4-hydroxy-2-nonenal protein,
TNF-alpha
and transforming growth factor-beta mRNA, and NF-kappaB binding activity in wild-type, but not gp91(-/-), mice. These results suggest that gp91(phox)-containing
NADPH oxidase
plays a crucial role in the pathophysiology of intermittent hypoxia-induced LV remodeling through an increase of oxidative stress.
...
PMID:Role of gp91phox-containing NADPH oxidase in left ventricular remodeling induced by intermittent hypoxic stress. 1832 95
Vascular endothelial cell activation by cytokines and other pro-inflammatory mediators is an initial event in atherosclerosis and in other vascular diseases. Simvastatin, a HMG-CoA reductase inhibitor, suppressed both tumor necrosis factor (TNF)-alpha- and angiotensin (Ang) II-induced monocyte adhesion to endothelial cells (an initial step in vascular inflammation) and reactive oxygen species (ROS) production. Diphenyleneiodonium and apocynin, both
NADPH oxidase
inhibitors, also suppressed
TNF-alpha
-induced ROS and monocyte-endothelial cell adhesion, demonstrating that
TNF-alpha
-induced monocyte adhesion is mediated through ROS produced by
NADPH oxidase
activation. Furthermore, exogenously applied mevalonate or geranylgeranylpyrophosphate in combination with simvastatin completely prevented the inhibitory effects of simvastatin on ROS generation and monocyte-endothelial cell adhesion by TNFalpha and Ang II. These results suggest that monocyte adhesion to endothelial cells induced by
TNF-alpha
or Ang II is mediated via the geranylgeranyl isoprenoid-dependent generation of ROS, and that this is inhibited by simvastatin.
...
PMID:Inhibitory effect of simvastatin on the TNF-alpha- and angiotensin II-induced monocyte adhesion to endothelial cells is mediated through the suppression of geranylgeranyl isoprenoid-dependent ROS generation. 1836 90
Dendritic cells (DC) express a functional
NADPH oxidase
and produce reactive oxygen species (ROS) upon interaction with microbes and T cells. Exposure to ROS leads to DC activation and maturation, as evidenced by phenotypic and functional changes. We have evaluated how endogenous ROS production affects the cytokine secretion pattern and T cell-activating capacity of bone marrow-derived murine DC. DC treated with ROS scavengers, as well as DC from mice that lack a functional
NADPH oxidase
(and thereby inherently deficient in ROS production) produced significantly increased levels of IL-1beta, IL-6,
TNF-alpha
and TGF-beta in response to microbial activation. DC deficient in ROS production induced high levels of IFN-gamma and IL-17 in responding T cells after Ag-specific or superantigen-induced activation. Finally, we show that ROS deficiency affected the induction of a T cell-dependent inflammatory condition, collagen-induced arthritis (CIA). C57BL/6 mice that lack a functional
NADPH oxidase
developed a severe and erosive CD4-dependent CIA, whereas the majority of the congenic wild-type animals remained healthy. These data suggest that ROS act as immunomodulators in DC-driven T cell activation and perhaps also in T cell-dependent immunopathology.
...
PMID:Th17 development and autoimmune arthritis in the absence of reactive oxygen species. 1838 34
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