scholarly journals Polymorphonuclear Leukocytes or Hydrogen Peroxide Enhance Biofilm Development of MucoidPseudomonas aeruginosa

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Qi Tan ◽  
Qing Ai ◽  
Qi Xu ◽  
Fang Li ◽  
Jialin Yu
Keyword(s):  
Polymorphonuclear Leukocytes ◽  
Free Oxygen Radicals ◽  
Free Oxygen ◽  
Alginate Production ◽  
Mucoid Conversion ◽  
Key Enzyme ◽  
Opportunistic Pathogenic ◽  
Biofilm Development ◽  
Human Infections ◽  
Chronic Lung Infection

Pseudomonas aeruginosais an opportunistic pathogenic bacterium involved in many human infections, including pneumonia, diabetic foot ulcers, and ventilator-associated pneumonia.P. aeruginosacells usually undergo mucoid conversion during chronic lung infection in patients with cystic fibrosis (CF) and resist destruction by polymorphonuclear leukocytes (PMNs), which release free oxygen radicals (ROS), such as H2O2. PMNs are the main leucocytes in the CF sputum of patients who are infected withP. aeruginosa, which usually forms biofilms. Here, we report that PMNs or H2O2can promote biofilm formation by mucoidP. aeruginosaFRD1 with the use of the hanging-peg method. The mucoid strain infecting CF patients overproduces alginate. In this study, PMNs and H2O2promoted alginate production, and biofilms treated with PMNs or H2O2exhibited higher expression of alginate genes. Additionally, PMNs increased the activity of GDP-mannose dehydrogenase, which is the key enzyme in alginate biosynthesis. Our results demonstrate that PMNs or H2O2can enhance mucoidP. aeruginosabiofilms.

The Dinitrophenol and Potassium Iodate Influence on Hordeum Vulgare Seedlings Viability\

2018 ◽  
Vol 69 (8) ◽  
pp. 2160-2166
Author(s):  
Elena Todirascu Ciornea ◽  
Gabriela Dumitru ◽  
Ion Sandu
Keyword(s):  
Oxidative Stress ◽  
Hordeum Vulgare ◽  
Antioxidant Enzyme ◽  
Oxygen Radicals ◽  
Free Oxygen Radicals ◽  
Potassium Iodate ◽  
Free Oxygen ◽  
Oxidative Stress Enzymes ◽  
Stress Enzymes ◽  
Seeds Germination

The using of the pesticides of dinitrophenol type in agriculture has as consequence the major pollution of the environment, the plants taking these substances from the soil and once with these ones they reach in the human and animal organism where they product disequilibrium that are interpreted through the accumulation of free oxygen radicals with direct repercussions on the antioxidant enzyme�s synthesis intensification and on their activity�s increase. The apply of treatments on the barley seeds had significant effects regarding the seeds� germination, the young plants� growth, the oxidative stress enzymes� activity, but also regarding the content of photoassimilators and carotenoids pigments.

scholarly journals Role of Oxidative Stress in the Pathogenesis of Amyotrophic Lateral Sclerosis: Antioxidant Metalloenzymes and Therapeutic Strategies

Biomolecules ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 437
Author(s):  
Pavlína Hemerková ◽  
Martin Vališ
Keyword(s):  
Oxidative Stress ◽  
Amyotrophic Lateral Sclerosis ◽  
Antioxidant Enzymes ◽  
Oxygen Radicals ◽  
Clinical Symptoms ◽  
Free Oxygen Radicals ◽  
Free Oxygen ◽  
Sporadic Als ◽  
Familial Form ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) affects motor neurons in the cerebral cortex, brainstem and spinal cord and leads to death due to respiratory failure within three to five years. Although the clinical symptoms of this disease were first described in 1869 and it is the most common motor neuron disease and the most common neurodegenerative disease in middle-aged individuals, the exact etiopathogenesis of ALS remains unclear and it remains incurable. However, free oxygen radicals (i.e., molecules containing one or more free electrons) are known to contribute to the pathogenesis of this disease as they very readily bind intracellular structures, leading to functional impairment. Antioxidant enzymes, which are often metalloenzymes, inactivate free oxygen radicals by converting them into a less harmful substance. One of the most important antioxidant enzymes is Cu2+Zn2+ superoxide dismutase (SOD1), which is mutated in 20% of cases of the familial form of ALS (fALS) and up to 7% of sporadic ALS (sALS) cases. In addition, the proper functioning of catalase and glutathione peroxidase (GPx) is essential for antioxidant protection. In this review article, we focus on the mechanisms through which these enzymes are involved in the antioxidant response to oxidative stress and thus the pathogenesis of ALS and their potential as therapeutic targets.

scholarly journals The Pseudomonas aeruginosa Sensor Kinase KinB Negatively Controls Alginate Production through AlgW-Dependent MucA Proteolysis

2009 ◽  
Vol 191 (7) ◽  
pp. 2285-2295 ◽  
Author(s):  
F. Heath Damron ◽  
Dongru Qiu ◽  
Hongwei D. Yu
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Response Regulator ◽  
Negative Regulator ◽  
Loss Of Function ◽  
Cystic Fibrosis Mutation ◽  
Strain Pao1 ◽  
Alginate Production ◽  
Mucoid Conversion ◽  
Σ Factor ◽  
Lung Infections

ABSTRACT Mucoidy, or overproduction of the exopolysaccharide known as alginate, in Pseudomonas aeruginosa is a poor prognosticator for lung infections in cystic fibrosis. Mutation of the anti-σ factor MucA is a well-accepted mechanism for mucoid conversion. However, certain clinical mucoid strains of P. aeruginosa have a wild-type (wt) mucA. Here, we describe a loss-of-function mutation in kinB that causes overproduction of alginate in the wt mucA strain PAO1. KinB is the cognate histidine kinase for the transcriptional activator AlgB. Increased alginate production due to inactivation of kinB was correlated with high expression at the alginate-related promoters P algU and P algD . Deletion of alternative σ factor RpoN (σ54) or the response regulator AlgB in kinB mutants decreased alginate production to wt nonmucoid levels. Mucoidy was restored in the kinB algB double mutant by expression of wt AlgB or phosphorylation-defective AlgB.D59N, indicating that phosphorylation of AlgB was not required for alginate overproduction when kinB was inactivated. The inactivation of the DegS-like protease AlgW in the kinB mutant caused loss of alginate production and an accumulation of the hemagglutinin (HA)-tagged MucA. Furthermore, we observed that the kinB mutation increased the rate of HA-MucA degradation. Our results also indicate that AlgW-mediated MucA degradation required algB and rpoN in the kinB mutant. Collectively, these studies indicate that KinB is a negative regulator of alginate production in wt mucA strain PAO1.

Participation of Free Oxygen Radicals in Damage of Porcine Erythrocytes

1981 ◽  
Vol 88 (1) ◽  
pp. 11 ◽  
Author(s):  
Z. Jóźwiak ◽  
Z. Helszer ◽  
Z. Jozwiak
Keyword(s):  
Oxygen Radicals ◽  
Free Oxygen Radicals ◽  
Free Oxygen

Oleuropein multicompartment nanovesicles enriched with collagen as a natural strategy for the treatment of skin wounds connected with oxidative stress

Nanomedicine ◽  
2021 ◽  
Author(s):  
Mohamad Allaw ◽  
Maria Letizia Manca ◽  
Juan Carmelo Gómez-Fernández ◽  
Josè Luis Pedraz ◽  
Maria Carmen Terencio ◽  
...  
Keyword(s):  
Cell Monolayer ◽  
Free Oxygen Radicals ◽  
Technological Properties ◽  
Free Oxygen ◽  
Skin Delivery ◽  
Low Toxicity ◽  
And Migration ◽  
Wounded Area ◽  
Proliferation And Migration

Aim: Collagen-enriched transfersomes, glycerosomes and glytransfersomes were specifically tailored for skin delivery of oleuropein. Methods: Vesicles were prepared by direct sonication and their main physicochemical and technological properties were measured. Biocompatibility, protective effect and promotion of the healing of a wounded cell monolayer were tested in vitro using fibroblasts. Results: Vesicles were mainly multicompartment, small (∼108 nm), slightly polydispersed (approximately 0.27) and negatively charged (~-49 mV). Oleuropein was incorporated in high amounts (approximately 87%) and vesicles were stable during four months of storage. In vitro studies confirmed the low toxicity of formulations (viability ≥95%), their effectiveness in counteracting nitric oxide generation and damages caused by free oxygen radicals, especially when collagen glytransfersomes were used (viability ~100%). These vesicles also promoted the regeneration of a wounded area by promoting the proliferation and migration of fibroblasts. Conclusion: Collagen-enriched vesicles are promising formulations capable of speeding up the healing of the wounded skin.

Markers of Neuroinflammation in the Serum of Prepubertal Children with Fetal Alcohol Spectrum Disorders

2021 ◽  
Vol 20 ◽  
Author(s):  
Marco Fiore ◽  
Carla Petrella ◽  
Giovanna Coriale ◽  
Pamela Rosso ◽  
Elena Fico ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Oxygen Radicals ◽  
Fetal Alcohol Spectrum Disorders ◽  
Serum Levels ◽  
Free Oxygen Radicals ◽  
Fetal Alcohol ◽  
Free Oxygen ◽  
Tnf Α ◽  
Spectrum Disorders ◽  
Fetal Alcohol Spectrum

Background: Fetal Alcohol Spectrum Disorders (FASD) are the manifestation of the damage caused by alcohol consumption during pregnancy. Children with Fetal Alcohol Syndrome (FAS), the extreme FASD manifestation, show both facial dysmorphology and mental retardation. Alcohol consumed during gestational age prejudices brain development by reducing, among others, the synthesis and release of neurotrophic factors and neuroinflammatory markers. Alcohol drinking induces also oxidative stress. Hypothesis/Objective : The present study aims at investigating the potential association between neurotrophins, neuroinflammation and oxidative stress in 12 prepubertal male and female FASD children diagnosed as FAS or partial FAS (pFAS). Methods: Accordingly, we analyzed, in the serum, the level of BDNF and NGF and the oxidative stress, as free oxygen radicals test (FORT) and free oxygen radicals defense (FORD). Moreover, serum levels of inflammatory mediators (IL-1α, IL-2, IL-6, IL-10, IL-12, MCP-1, TGF-β and TNF-α) involved in neuroinflammatory and oxidative processes have been investigated. Results: We demonstrated in pre-pubertal FASD children low serum levels of NGF and BDNF, respect to healthy controls. These changes were associated with higher serum presence of TNF-α and IL-1α. Quite interestingly, an elevation in the FORD was also found despite normal FORT levels. Moreover, we found a potentiation of IL-1α, IL-2, IL-10 and IL-1α1 in the analyzed female compared to male children. Conclusion: The present investigation shows an imbalance in the peripheral neuroimmune pathways that could be used in children as early biomarkers of the deficits observed in FASD.

scholarly journals Phosphatidylinositide 3-kinase localizes to cytoplasmic lipid bodies in human polymorphonuclear leukocytes and other myeloid-derived cells

Blood ◽  
2000 ◽  
Vol 95 (3) ◽  
pp. 1078-1085 ◽  
Author(s):  
Wengui Yu ◽  
Jessica Cassara ◽  
Peter F. Weller
Keyword(s):  
Intracellular Signaling ◽  
Polymorphonuclear Leukocytes ◽  
Membrane Receptors ◽  
Lipid Bodies ◽  
Catalytic Subunits ◽  
Lyn Kinase ◽  
Key Enzyme ◽  
Intracellular Vesicles ◽  
Plasma Membrane Receptors ◽  
Human Polymorphonuclear Leukocytes

Phosphatidylinositide 3-kinase (PI3K) is a key enzyme implicated in intracellular signaling of diverse cellular responses including receptor-mediated responses and neutrophil activation. Several PI3K subunits have been cloned and shown to be localized to plasma membrane receptors, the cytosol, or intracellular vesicles or caveolae. We report the localization of PI3K to a distinct intracellular site, cytoplasmic lipid bodies, in leukocytes. In U937 monocyte cells, PI3K p85 regulatory and p110β catalytic subunits were localized to lipid bodies by immunocytochemistry and/or immunoblotting and enzyme assays of subcellular fractions. In RAW murine macrophages, p55, p85, and p85β PI3K subunits were present at isolated lipid bodies. PI3K p85 was also shown to colocalize and, by co-immunoprecipitation, to be physically associated with phosphorylated Lyn kinase in lipid bodies induced to form in human polymorphonuclear leukocytes. These findings, therefore, indicate a novel site for PI3K compartmentalization and suggest that PI3K-mediated signaling is active within cytoplasmic lipid bodies in leukocytes.

scholarly journals Neuroinflammatory Markers in the Serum of Prepubertal Children with Down Syndrome

2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Luigi Tarani ◽  
Valentina Carito ◽  
Giampiero Ferraguti ◽  
Carla Petrella ◽  
Antonio Greco ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Oxygen Radicals ◽  
Serum Levels ◽  
Free Oxygen Radicals ◽  
Immune Functions ◽  
Free Oxygen ◽  
Prepubertal Children ◽  
Chromosomal Disorder ◽  
Oxidative Processes ◽  
Physical Features

Down Syndrome (DS) is the most common chromosomal disorder. Although DS individuals are mostly perceived as characterized by some distinct physical features, cognitive disabilities, and cardiac defects, they also show important dysregulations of immune functions. While critical information is available for adults with DS, little literature is available on the neuroinflammation in prepubertal DS children. We aimed to evaluate in prepubertal DS children the serum levels of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), oxidative stress as free oxygen radicals defense (FORD), free oxygen radicals test (FORT), and cytokines playing key roles in neuroinflammation and oxidative processes as TNF-α, TGF-β, MCP-1, IL-1α, IL-2, IL-6, IL-10, and IL-12. No differences were found in NGF between DS children and controls. However, BDNF was higher in DS subjects compared to controls. We also did not reveal changes in FORD and FORT. Quite interestingly, the serum of DS children disclosed a marked decrease in all analyzed cytokines with evident differences in serum cytokine presence between male and female DS children. In conclusion, the present study evidences in DS prepubertal children a disruption in the neurotrophins and immune system pathways.

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