scholarly journals An Abnormal Nitric Oxide Metabolism Contributes to Brain Oxidative Stress in the Mouse Model for the Fragile X Syndrome, a Possible Role in Intellectual Disability

2016 ◽  
Vol 2016 ◽  
pp. 1-12 ◽  
Author(s):  
Elena Lima-Cabello ◽  
Francisco Garcia-Guirado ◽  
Rocio Calvo-Medina ◽  
Rajaa el Bekay ◽  
Lucia Perez-Costillas ◽  
...  

Background.Fragile X syndrome is the most common genetic cause of mental disability. Although many research has been performed, the mechanism underlying the pathogenesis is unclear and needs further investigation. Oxidative stress played major roles in the syndrome. The aim was to investigate the nitric oxide metabolism, protein nitration level, the expression of NOS isoforms, and furthermore the activation of the nuclear factor NF-κB-p65 subunit in different brain areas on the fragile X mouse model.Methods.This study involved adult male Fmr1-knockout and wild-type mice as controls. We detected nitric oxide metabolism and the activation of the nuclear factor NF-κBp65 subunit, comparing the mRNA expression and protein content of the three NOS isoforms in different brain areas.Results.Fmr1-KO mice showed an abnormal nitric oxide metabolism and increased levels of protein tyrosine nitrosylation. Besides that, nuclear factor NF-κB-p65 and inducible nitric oxide synthase appeared significantly increased in the Fmr1-knockout mice. mRNA and protein levels of the neuronal nitric oxide synthase appeared significantly decreased in the knockout mice. However, the epithelial nitric oxide synthase isoform displayed no significant changes.Conclusions.These data suggest the potential involvement of an abnormal nitric oxide metabolism in the pathogenesis of the fragile X syndrome.

2007 ◽  
Vol 102 (1) ◽  
pp. 157-162 ◽  
Author(s):  
Darin Van Gammeren ◽  
Darin J. Falk ◽  
Melissa A. Deering ◽  
Keith C. DeRuisseau ◽  
Scott K. Powers

Mechanical ventilation (MV) is associated with diaphragmatic oxidative stress that contributes to both diaphragmatic atrophy and contractile dysfunction. However, the pathways responsible for oxidant production in the diaphragm during MV remain unknown. To address this issue, we tested the hypothesis that diaphragmatic nitric oxide synthase (NOS) activity is elevated during MV, resulting in nitration of diaphragmatic proteins. Rats were mechanically ventilated for 18 h, and time-matched, anesthetized but spontaneously breathing animals served as controls. Protein levels of endothelial NOS, inducible NOS, and neuronal NOS were measured in diaphragms from all animals. 3-Nitrotyrosine levels were also measured as an index of protein nitration, and S-nitrosothiol levels were measured as a marker of nitric oxide reactions with molecules containing sulfhydryl groups. Levels of nitrates and nitrites were measured as markers of stable end products of nitric oxide metabolism. Finally, as a marker of oxidative stress, diaphragmatic levels of reduced GSH were also analyzed. MV did not promote an increase in diaphragmatic protein levels of endothelial NOS or neuronal NOS. Moreover, inducible NOS was not detected in the diaphragms of either experimental group. Consistent with these findings, MV did not elevate diaphragmatic 3-nitrotyrosine levels in any subcellular fraction of the diaphragm, including the cytosolic, mitochondrial, membrane, and insoluble protein fractions. Moreover, prolonged MV did not elevate diaphragmatic levels of S-nitrosothiols, nitrate, or nitrite. Finally, prolonged MV significantly reduced diaphragmatic levels of GSH, which is consistent with diaphragmatic oxidative stress. Collectively, these data reveal that MV-induced oxidative stress in the diaphragm is not due to increases in nitric oxide production by NOS.


2021 ◽  
pp. 096032712199944
Author(s):  
Mohamed IA Hassan ◽  
Fares EM Ali ◽  
Abdel-Gawad S Shalkami

Aim: Hepatic ischemia/reperfusion (I/R) injury is a syndrome involved in allograft dysfunction. This work aimed to elucidate carvedilol (CAR) role in hepatic I/R injury. Methods: Male rats were allocated to Sham group, CAR group, I/R group and CAR plus I/R group. Rats subjected to hepatic ischemia for 30 minutes then reperfused for 60 minutes. Oxidative stress markers, inflammatory cytokines and nitric oxide synthases were measured in hepatic tissues. Results: Hepatocyte injury following I/R was confirmed by a marked increase in liver enzymes. Also, hepatic I/R increased the contents of malondialdehyde however decreased glutathione contents and activities of antioxidant enzymes. Furthermore, hepatic I/R caused elevation of toll-like receptor-4 (TLR-4) expression and inflammatory mediators levels such as tumor necrosis factor-α, interleukin-6 and cyclooxygenase-II. Hepatic I/R caused down-regulation of endothelial nitric oxide synthase and upregulation of inducible nitric oxide synthase expressions. CAR treatment before hepatic I/R resulted in the restoration of liver enzymes. Administration of CAR caused a significant correction of oxidative stress and inflammation markers as well as modulates the expression of endothelial and inducible nitric oxide synthase. Conclusions: CAR protects liver from I/R injury through reduction of the oxidative stress and inflammation, and modulates endothelial and inducible nitric oxide synthase expressions.


2016 ◽  
Vol 310 (1) ◽  
pp. H39-H48 ◽  
Author(s):  
Masashi Mukohda ◽  
Madeliene Stump ◽  
Pimonrat Ketsawatsomkron ◽  
Chunyan Hu ◽  
Frederick W. Quelle ◽  
...  

Loss of peroxisome proliferator-activated receptor (PPAR)-γ function in the vascular endothelium enhances atherosclerosis and NF-κB target gene expression in high-fat diet-fed apolipoprotein E-deficient mice. The mechanisms by which endothelial PPAR-γ regulates inflammatory responses and protects against atherosclerosis remain unclear. To assess functional interactions between PPAR-γ and inflammation, we used a model of IL-1β-induced aortic dysfunction in transgenic mice with endothelium-specific overexpression of either wild-type (E-WT) or dominant negative PPAR-γ (E-V290M). IL-1β dose dependently decreased IκB-α, increased phospho-p65, and increased luciferase activity in the aorta of NF-κB-LUC transgenic mice. IL-1β also dose dependently reduced endothelial-dependent relaxation by ACh. The loss of ACh responsiveness was partially improved by pretreatment of the vessels with the PPAR-γ agonist rosiglitazone or in E-WT. Conversely, IL-1β-induced endothelial dysfunction was worsened in the aorta from E-V290M mice. Although IL-1β increased the expression of NF-κB target genes, NF-κB p65 inhibitor did not alleviate endothelial dysfunction induced by IL-1β. Tempol, a SOD mimetic, partially restored ACh responsiveness in the IL-1β-treated aorta. Notably, tempol only modestly improved protection in the E-WT aorta but had an increased protective effect in the E-V290M aorta compared with the aorta from nontransgenic mice, suggesting that PPAR-γ-mediated protection involves antioxidant effects. IL-1β increased ROS and decreased the phospho-endothelial nitric oxide synthase (Ser1177)-to-endothelial nitric oxide synthase ratio in the nontransgenic aorta. These effects were completely abolished in the aorta with endothelial overexpression of WT PPAR-γ but were worsened in the aorta with E-V290M even in the absence of IL-1β. We conclude that PPAR-γ protects against IL-1β-mediated endothelial dysfunction through a reduction of oxidative stress responses but not by blunting IL-1β-mediated NF-κB activity.


2000 ◽  
Vol 68 (12) ◽  
pp. 7087-7093 ◽  
Author(s):  
Y.-H. Li ◽  
Z.-Q. Yan ◽  
J. Skov Jensen ◽  
K. Tullus ◽  
A. Brauner

ABSTRACT Chronic lung disease (CLD) of prematurity is an inflammatory disease with a multifactorial etiology. The importance ofUreaplasma urealyticum in the development of CLD is debated, and steroids produce some improvement in neonates with this disease. In the present study, the capability of U. urealyticum to stimulate rat alveolar macrophages to produce nitric oxide (NO), express inducible nitric oxide synthase (iNOS), and activate nuclear factor κB (NF-κB) in vitro was characterized. The effect of NO on the growth of U. urealyticum was also investigated. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticum antigen (≥4 × 107 color-changing units/ml) stimulated alveolar macrophages to produce NO in a dose- and time-dependent manner (P < 0.05). This effect was further enhanced by gamma interferon (100 IU/ml; P < 0.05) but was attenuated by budesonide and dexamethasone (10−4 to 10−6 M) (P < 0.05). The mRNA and protein levels of iNOS were also induced in response to U. urealyticum and inhibited by steroids.U. urealyticum antigen triggered NF-κB activation, a possible mechanism for the induced iNOS expression, which also was inhibited by steroids. NO induced by U. urealyticum caused a sixfold reduction of its own growth after infection for 10 h. Our findings imply that U. urealyticum may be an important factor in the development of CLD. The host defense response againstU. urealyticum infection may also be influenced by NO. The down-regulatory effect of steroids on NF-κB activation, iNOS expression, and NO production might partly explain the beneficial effect of steroids in neonates with CLD.


Nitric Oxide ◽  
2007 ◽  
Vol 16 (3) ◽  
pp. 331-338 ◽  
Author(s):  
Roberto M. Saraiva ◽  
Khalid M. Minhas ◽  
Meizi Zheng ◽  
Eleanor Pitz ◽  
Adriana Treuer ◽  
...  

2014 ◽  
Vol 289 (40) ◽  
pp. 27540-27550 ◽  
Author(s):  
Sabine Kossmann ◽  
Hanhan Hu ◽  
Sebastian Steven ◽  
Tanja Schönfelder ◽  
Daniela Fraccarollo ◽  
...  

Neurosignals ◽  
2001 ◽  
Vol 10 (1-2) ◽  
pp. 57-65 ◽  
Author(s):  
Pedram Ghafourifar ◽  
Urs Bringold ◽  
Sabine D. Klein ◽  
Christoph Richter

2003 ◽  
Vol 94 (6) ◽  
pp. 2534-2544 ◽  
Author(s):  
Wieslaw Kozak ◽  
Anna Kozak

Male C57BL/6J mice deficient in nitric oxide synthase (NOS) genes (knockout) and control (wild-type) mice were implanted intra-abdominally with battery-operated miniature biotelemeters (model VMFH MiniMitter, Sunriver, OR) to monitor changes in body temperature. Intravenous injection of lipopolysaccharide (LPS; 50 μg/kg) was used to trigger fever in response to systemic inflammation in mice. To induce a febrile response to localized inflammation, the mice were injected subcutaneously with pure turpentine oil (30 μl/animal) into the left hindlimb. Oral administration (gavage) of N G-monomethyl-l-arginine (l-NMMA) for 3 days (80 mg · kg−1 · day−1in corn oil) before injection of pyrogens was used to inhibit all three NOSs ( N G-monomethyl-d-arginine acetate salt and corn oil were used as control). In normal male C57BL/6J mice, l-NMMA inhibited the LPS-induced fever by ∼60%, whereas it augmented fever by ∼65% in mice injected with turpentine. Challenging the respective NOS knockout mice with LPS and with l-NMMA revealed that inducible NOS and neuronal NOS isoforms are responsible for the induction of fever to LPS, whereas endothelial NOS (eNOS) is not involved. In contrast, none of the NOS isoforms appeared to trigger fever to turpentine. Inhibition of eNOS, however, exacerbates fever in mice treated with l-NMMA and turpentine, indicating that eNOS participates in the antipyretic mechanism. These data support the hypothesis that nitric oxide is a regulator of fever. Its action differs, however, depending on the pyrogen used and the NOS isoform.


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