scholarly journals Glutathione and Catalase Provide Overlapping Defenses for Protection against Respiration-Generated Hydrogen Peroxide in Haemophilus influenzae

2003 ◽  
Vol 185 (18) ◽  
pp. 5555-5562 ◽  
Author(s):  
Bjorn Vergauwen ◽  
Frederik Pauwels ◽  
Jozef J. Van Beeumen
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Haemophilus Influenzae ◽  
Growth Medium ◽  
Primary System ◽  
Aerobic Growth ◽  
Cellular Processes ◽  
Defense Systems ◽  
And Oxidative Stress

ABSTRACT Glutathione is an abundant and ubiquitous low-molecular-weight thiol that may play a role in many cellular processes, including protection against the deleterious effects of reactive oxygen species. We address here the role of glutathione in protection against hydrogen peroxide (H2O2) in Haemophilus influenzae and show that glutathione and catalase provide overlapping defense systems. H. influenzae is naturally glutathione deficient and imports glutathione from the growth medium. Mutant H. influenzae lacking catalase and cultured in glutathione-deficient minimal medium is completely devoid of H2O2 scavenging activity and, accordingly, substantial amounts of H2O2 accumulate in the growth medium. H. influenzae generates H2O2 at rates similar to those reported for Escherichia coli, but the toxicity of this harmful metabolite is averted by glutathione-based H2O2 removal, which appears to be the primary system for protection against H2O2 endogenously generated during aerobic respiration. When H2O2 concentrations exceed low micromolar levels, the hktE gene-encoded catalase becomes the predominant scavenger. The requirement for glutathione in protection against oxidative stress is analogous to that in higher and lower eukaryotes but is unlike the situation in other bacteria in which glutathione is dispensable for aerobic growth during both normal and oxidative stress conditions.

scholarly journals The Golgi apparatus in neurorestoration

2019 ◽  
Vol 7 (3) ◽  
pp. 116-128
Author(s):  
Jianyang Liu ◽  
Jialin He ◽  
Yan Huang ◽  
Han Xiao ◽  
Zheng Jiang ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Golgi Apparatus ◽  
Neurodegenerative Diseases ◽  
Disease Progression ◽  
Neurological Recovery ◽  
Cellular Processes ◽  
Wide Range ◽  
And Oxidative Stress

The central role of the Golgi apparatus in critical cellular processes such as the transport, processing, and sorting of proteins and lipids has placed it at the forefront of cell science. Golgi apparatus dysfunction caused by primary defects within the Golgi or pharmacological and oxidative stress has been implicated in a wide range of neurodegenerative diseases. In addition to participating in disease progression, the Golgi apparatus plays pivotal roles in angiogenesis, neurogenesis, and synaptogenesis, thereby promoting neurological recovery. In this review, we focus on the functions of the Golgi apparatus and its mediated events during neurorestoration.

ROLE OF PREGNAN-X-RECEPTOR IN CELL RESISTANCE TO NITROSATIVE AND OXIDATIVE STRESS

2021 ◽  
Author(s):  
Yulia Abalenikhina ◽  
◽  
Elena A. Sudakova ◽  
Pelageya Erokhina ◽  
Aleksey Shchulkin ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Cell Viability ◽  
Nitrosative Stress ◽  
Pregnane X Receptor ◽  
Cell Resistance ◽  
Oxidative And Nitrosative Stress ◽  
High Concentrations ◽  
And Oxidative Stress

The article discusses the new role of pregnane X receptor (PXR) under conditions of oxidative and nitrosative stress. The results showed that the effect of hydrogen peroxide and S-nitrosoglu-tathione in high concentrations on Caco-2 cells leads to a decrease in cell viability, which is accompanied by an increase in the amount of PXR. These changes are offset by the addition of ketoconazole (inhibitor of PXR) to the medium.

Role of hydrogen peroxide and oxidative stress in healing responses

2002 ◽  
Vol 59 (11) ◽  
pp. 1872-1891 ◽  
Author(s):  
M. Rojkind ◽  
J.-A. Domínguez-Rosales ◽  
N. Nieto ◽  
P. Greenwel
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
And Oxidative Stress

The Effect of Resveratrol on Neurodegenerative Disorders: Possible Protective Actions Against Autophagy, Apoptosis, Inflammation and Oxidative Stress

2019 ◽  
Vol 25 (19) ◽  
pp. 2178-2191 ◽  
Author(s):  
Mohammad H. Pourhanifeh ◽  
Rana Shafabakhsh ◽  
Russel J. Reiter ◽  
Zatollah Asemi
Keyword(s):  
Oxidative Stress ◽  
Neurodegenerative Disorders ◽  
Cell Damage ◽  
Current Evidence ◽  
Therapeutic Effects ◽  
Neuronal Function ◽  
Beneficial Effects ◽  
Cellular Processes ◽  
And Oxidative Stress

The prevalence of neurodegenerative disorders characterized by the loss of neuronal function is rapidly increasing. The pathogenesis of the majority of these diseases is not entirely clear, but current evidence has shown the possibility that autophagy, apoptosis, inflammation and oxidative stress are involved. The present review summarizes the therapeutic effects of resveratrol on neurodegenerative disorders, based on the especially molecular biology of these diseases. The PubMed, Cochrane, Web of Science and Scopus databases were searched for studies published in English until March 30th, 2019 that contained data for the role of inflammation, oxidative stress, angiogenesis and apoptosis in the neurodegenerative disorders. There are also studies documenting the role of molecular processes in the progression of central nervous system diseases. Based on current evidence, resveratrol has potential properties that may reduce cell damage due to inflammation. This polyphenol affects cellular processes, including autophagy and the apoptosis cascade under stressful conditions. Current evidence supports the beneficial effects of resveratrol on the therapy of neurodegenerative disorders.

Evaluation of the role of enzymatic and nonenzymatic antioxidant systems in the radiation resistance of Deinococcus

2010 ◽  
Vol 56 (3) ◽  
pp. 195-201 ◽  
Author(s):  
Ravindranath Shashidhar ◽  
Sanjukta A. Kumar ◽  
Hari S. Misra ◽  
Jayant R. Bandekar
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Stress Resistance ◽  
Radiation Resistance ◽  
Resistant Bacteria ◽  
Antioxidant Systems ◽  
Defense Systems ◽  
Antioxidant Metabolites ◽  
Radiation Resistant

Antioxidant enzymes and antioxidant metabolites appear to have different roles in the oxidative stress resistance responses of radiation-resistant bacteria belonging to the Deinococcus – Thermus group. Twelve distinct strains belonging to 7 Deinococcus species were characterized for their responses to hydrogen peroxide, ciprofloxacin, and ionizing radiation. The levels of catalase and peroxidase activities in these strains showed a positive correlation with resistance to hydrogen peroxide and ciprofloxacin. However, the levels of these enzymes and carotenoids did not appear to contribute significantly to radiation resistance. Our findings support the idea that enzymatic defense systems are not sufficient to account for the extreme radiation resistance of Deinococcus species. Consistent with previously published reports, the Deinococcus strains had high intracellular manganese/iron ratios. No significant correlation was found between intracellular manganese/iron ratios and radiation resistance within different Deinococcus species, suggesting that other components are involved in conferring radiation resistance.

Inhibition of microRNA-155 Alleviates Neurological Dysfunction Following Transient Global Ischemia and Contribution of Neuroinflammation and Oxidative Stress in the Hippocampus

2020 ◽  
Vol 25 (40) ◽  
pp. 4310-4317 ◽  
Author(s):  
Lichao Sun ◽  
Shouqin Ji ◽  
Jihong Xing
Keyword(s):  
Oxidative Stress ◽  
Brain Edema ◽  
Severity Score ◽  
Global Ischemia ◽  
Signal Pathways ◽  
Neurological Severity Score ◽  
Tnf Α ◽  
Transient Global Ischemia ◽  
And Oxidative Stress

Background/Aims: Central pro-inflammatory cytokine (PIC) signal is involved in neurological deficits after transient global ischemia induced by cardiac arrest (CA). The present study was to examine the role of microRNA- 155 (miR-155) in regulating IL-1β, IL-6 and TNF-α in the hippocampus of rats with induction of CA. We further examined the levels of products of oxidative stress 8-isoprostaglandin F2α (8-iso PGF2α, indication of oxidative stress); and 8-hydroxy-2’-deoxyguanosine (8-OHdG, indication of protein oxidation) after cerebral inhibition of miR-155. Methods: CA was induced by asphyxia and followed by cardiopulmonary resuscitation in rats. ELISA and western blot analysis were used to determine the levels of PICs and products of oxidative stress; and the protein expression of NADPH oxidase (NOXs) in the hippocampus. In addition, neurological severity score and brain edema were examined to assess neurological functions. Results: We observed amplification of IL-1β, IL-6 and TNF-α along with 8-iso PGF2α and 8-OHdG in the hippocampus of CA rats. Cerebral administration of miR-155 inhibitor diminished upregulation of PICs in the hippocampus. This also attenuated products of oxidative stress and upregulation of NOX4. Notably, inhibition of miR-155 improved neurological severity score and brain edema and this was linked to signal pathways of PIC and oxidative stress. Conclusion: We showed the significant role of blocking miR-155 signal in improving the neurological function in CA rats likely via inhibition of signal pathways of neuroinflammation and oxidative stress, suggesting that miR-155 may be a target in preventing and/or alleviating development of the impaired neurological functions during CA-evoked global cerebral ischemia.

LncRNA SNHG12 Improves Cerebral Ischemic-reperfusion Injury by Activating SIRT1/FOXO3a Pathway through I nhibition of Autophagy and Oxidative Stress

2020 ◽  
Vol 17 (4) ◽  
pp. 394-401
Author(s):  
Yuanhua Wu ◽  
Yuan Huang ◽  
Jing Cai ◽  
Donglan Zhang ◽  
Shixi Liu ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Molecular Mechanisms ◽  
Ischemia Reperfusion ◽  
Critical Role ◽  
Cell Activity ◽  
Ht22 Cells ◽  
Cerebral Ischemic ◽  
Cerebral Ischemic Reperfusion ◽  
And Oxidative Stress

Background: Ischemia/reperfusion (I/R) injury involves complex biological processes and molecular mechanisms such as autophagy. Oxidative stress plays a critical role in the pathogenesis of I/R injury. LncRNAs are the regulatory factor of cerebral I/R injury. Methods: This study constructs cerebral I/R model to investigate role of autophagy and oxidative stress in cerebral I/R injury and the underline regulatory mechanism of SIRT1/ FOXO3a pathway. In this study, lncRNA SNHG12 and FOXO3a expression was up-regulated and SIRT1 expression was down-regulated in HT22 cells of I/R model. Results: Overexpression of lncRNA SNHG12 significantly increased the cell viability and inhibited cerebral ischemicreperfusion injury induced by I/Rthrough inhibition of autophagy. In addition, the transfected p-SIRT1 significantly suppressed the release of LDH and SOD compared with cells co-transfected with SIRT1 and FOXO3a group and cells induced by I/R and transfected with p-SNHG12 group and overexpression of cells co-transfected with SIRT1 and FOXO3 further decreased the I/R induced release of ROS and MDA. Conclusion: In conclusion, lncRNA SNHG12 increased cell activity and inhibited oxidative stress through inhibition of SIRT1/FOXO3a signaling-mediated autophagy in HT22 cells of I/R model. This study might provide new potential therapeutic targets for further investigating the mechanisms in cerebral I/R injury and provide.

The Concomitance of Hypertension and Diabetes Exacerbating Retinopathy: The Role of Inflammation and Oxidative Stress.

2013 ◽  
Vol 8 (4) ◽  
pp. 266-277 ◽  
Author(s):  
Diego Duarte ◽  
Kamila Silva ◽  
Mariana Rosales ◽  
José Lopes de Faria ◽  
Jacqueline Lopes de Faria
Keyword(s):  
Oxidative Stress ◽  
And Oxidative Stress

Hydrogen peroxide and quercetin induced changes on cell viability, apoptosis and oxidative stress in HepG2 cells

2020 ◽  
Vol 01 ◽  
Author(s):  
Ayşe Mine Yılmaz ◽  
Gökhan Biçim ◽  
Kübra Toprak ◽  
Betül Karademir Yılmaz ◽  
Irina Milisav ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Cycle ◽  
Hydrogen Peroxide ◽  
Cell Viability ◽  
Hepg2 Cells ◽  
Proteasome Activity ◽  
Cell Cycle Phases ◽  
Induced Changes ◽  
And Oxidative Stress ◽  
Quercetin Treatment

Background: Different cellular responses influence the progress of cancer. In this study, we have investigated the effect of hydrogen peroxide and quercetin induced changes on cell viability, apoptosis and oxidative stress in human hepatocellular carcinoma (HepG2) cells. Methods: The effects of hydrogen peroxide and quercetin on cell viability, cell cycle phases and oxidative stress related cellular changes were investigated. Cell viability was assessed by WST-1 assay. Apoptosis rate, cell cycle phase changes and oxidative stress were measured by flow cytometry. Protein expressions of p21, p27, p53, NF-Kβ-p50 and proteasome activity were determined by Western blot and fluorometry, respectively. Results: Hydrogen peroxide and quercetin treatment resulted in decreased cell viability and increased apoptosis in HepG2 cells. Proteasome activity was increased by hydrogen peroxide but decreased by quercetin treatment. Conclusion: Both agents resulted in decreased p53 protein expression and increased cell death by different mechanisms regarding proteostasis and cell cycle phases.

scholarly journals Molecular Mechanisms of Obesity-Linked Cardiac Dysfunction: An Up-Date on Current Knowledge

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 629
Author(s):  
Jorge Gutiérrez-Cuevas ◽  
Ana Sandoval-Rodriguez ◽  
Alejandra Meza-Rios ◽  
Hugo Christian Monroy-Ramírez ◽  
Marina Galicia-Moreno ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cardiac Dysfunction ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Peroxisome Proliferator ◽  
White Adipocyte ◽  
Peroxisome Proliferator Activated Receptors ◽  
And Oxidative Stress

Obesity is defined as excessive body fat accumulation, and worldwide obesity has nearly tripled since 1975. Excess of free fatty acids (FFAs) and triglycerides in obese individuals promote ectopic lipid accumulation in the liver, skeletal muscle tissue, and heart, among others, inducing insulin resistance, hypertension, metabolic syndrome, type 2 diabetes (T2D), atherosclerosis, and cardiovascular disease (CVD). These diseases are promoted by visceral white adipocyte tissue (WAT) dysfunction through an increase in pro-inflammatory adipokines, oxidative stress, activation of the renin-angiotensin-aldosterone system (RAAS), and adverse changes in the gut microbiome. In the heart, obesity and T2D induce changes in substrate utilization, tissue metabolism, oxidative stress, and inflammation, leading to myocardial fibrosis and ultimately cardiac dysfunction. Peroxisome proliferator-activated receptors (PPARs) are involved in the regulation of carbohydrate and lipid metabolism, also improve insulin sensitivity, triglyceride levels, inflammation, and oxidative stress. The purpose of this review is to provide an update on the molecular mechanisms involved in obesity-linked CVD pathophysiology, considering pro-inflammatory cytokines, adipokines, and hormones, as well as the role of oxidative stress, inflammation, and PPARs. In addition, cell lines and animal models, biomarkers, gut microbiota dysbiosis, epigenetic modifications, and current therapeutic treatments in CVD associated with obesity are outlined in this paper.

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