scholarly journals Habitat of In Vivo Transformation Influences the Levels of Free Radical Scavengers in Clinostomum complanatum: Implications for Free Radical Scavenger Based Vaccines against Trematode Infections

PLoS ONE ◽  
2014 ◽  
Vol 9 (4) ◽  
pp. e95858
Author(s):  
Atif Zafar ◽  
Asim Rizvi ◽  
Irshad Ahmad ◽  
Masood Ahmad
Keyword(s):  
Free Radical ◽  
Free Radical Scavenger ◽  
Free Radical Scavengers ◽  
Radical Scavenger ◽  
Radical Scavengers ◽  
Trematode Infections ◽  
Clinostomum Complanatum

Ultrastructural Evaluation of Ischemic Skeletal Muscle Reperfused with Oxygen Free Radical Scavengers

1988 ◽  
Vol 46 ◽  
pp. 262-263
Author(s):  
A. Mathur ◽  
R.C. Russell ◽  
A.C. Roth ◽  
D. Wagahoff
Keyword(s):  
Skeletal Muscle ◽  
Free Radical ◽  
White Male ◽  
Oxygen Free Radical ◽  
Free Radical Scavenger ◽  
Free Radical Scavengers ◽  
Radical Scavenger ◽  
Radical Scavengers ◽  
Tibialis Muscle ◽  
The Right

Skeletal muscle is very sensitive to ischemia. A prolonged preoperative ischemic interval decreases the chances for successful replantation of an amputated limb. Recent experimental work has implicated toxic oxygen free radicals produced during reperfusion of ischemic tissue to be responsible for some of the observed deleterious cellular changes. Selected oxygen free radical scavengers have been used to increase skeletal muscle survival following total ischemia. This study examined the effect of systemic administration of a superoxide free radical scavenger, superoxide dismutase (SOD), and a hydroxyl radical scavenger, dimethylsulfoxide (DMSO) just prior to reperfusion, on the ultrastructure and function of ischemic rabbit anterior tibialis muscle.White male New Zealand rabbits were used for this study. The right hind limb of each rabbit was made ischemic by dissecting and clamping the femoral artery and vein proximal to the bifurcation of the profundus artery and vein. A penrose tourniquet was also placed around the knee. The animals were divided into groups subjected to either 5 or 8 hours of ischemia.

Free Radical Scavengers, Antioxidants and Aldose Reductase Inhibitors from Camptosorus sibiricus Rupr.

2008 ◽  
Vol 63 (1-2) ◽  
pp. 66-68 ◽  
Author(s):  
Ning Li ◽  
Xian Li ◽  
Yi Zhang ◽  
Tao Wang ◽  
Wan Xiao
Keyword(s):  
Free Radical ◽  
Aldose Reductase ◽  
Free Radical Scavenger ◽  
Free Radical Scavengers ◽  
Radical Scavenger ◽  
Scavenging Activity ◽  
Radical Scavengers ◽  
Reductase Inhibitors ◽  
Dpph Scavenging Activity ◽  
Dpph Scavenging

Flavonoids and organic acids were recommended in the literature as the main active constituents of Camptosorus sibiricus Rupr. Assay-guided fractionation led to the isolation of 9 flavonoids and 8 phenolic acids. All compounds were tested for DPPH scavenging activity, SOD-like and aldose reductase inhibition. Among them, compounds 1, 2, 3, 5, 6, 7, 8, 9, 11, 15 showed activities. The most active free radical scavenger and antioxidant was compound 8, while compound 1 exhibited strong inhibiting activity of aldose reductase. The structureactivity relation was dicussed briefly.

scholarly journals Bioimmunological responses to Schistosoma mansoni and Fasciola gigantica worm homogenates either with or without saponin

2010 ◽  
Vol 4 (05) ◽  
pp. 334-344
Author(s):  
Amany Sayed Maghraby ◽  
Manal Abdel-Aziz Hamed ◽  
Sanaa Ahmed Ali
Keyword(s):  
Free Radical ◽  
Liver Function ◽  
Schistosoma Mansoni ◽  
Subcutaneous Administration ◽  
Free Radical Scavenger ◽  
Fasciola Gigantica ◽  
Free Radical Scavengers ◽  
Radical Scavenger ◽  
Immune Mediated ◽  
Mice Liver

Background: In this study, we evaluated the biochemical, immunological, histopathological and antischistosomal activities of Schistosoma mansoni or Fasciola gigantica worm homogenates mixed either with or without saponin that was extracted from Atriplex nummularia. Methodology: The immunization schedule was based on subcutaneous administration of two doses (50 μg /100 μl PBS) of each homogenate with time intervals of 15 days. After 15 days of the last homogenate inoculation, all mice were challenged with 100 Schistosoma mansoni cercariae and sacrificed after two months. Free radical scavengers and liver function enzymes were determined in mice liver. Worm counting and the histopathological picture of the liver were also done. Results: Immunization with Schistosoma or Fasciola worm homogenates, mixed either with or without saponin, recorded an amelioration of the free radical scavenger levels, liver function enzymes and reduction in worm burden, as well as improvement of the histological feature of the liver, the number and size of granuloma, evidence of increased immune reaction manifested by a lymphocytic cuff surrounding the granuloma, diminution of its fibrotic and collagen content, and destruction of Schistosoma ova. Conclusion: Fasciola or Schistosoma worm antigens mixed with or without saponin succeeded to eliminate the product of oxidative stress and assistance in immune-mediated destruction of eggs that ameliorate the histopathological picture of the liver cells and preserve its function.

scholarly journals Hydroxyl radical induced structural changes of collagen

2007 ◽  
Vol 21 (2) ◽  
pp. 91-103 ◽  
Author(s):  
Helan Xiao ◽  
Guoping Cai ◽  
Mingyao Liu
Keyword(s):  
Free Radical ◽  
Hydroxyl Radicals ◽  
Structural Changes ◽  
Type I Collagen ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Type I ◽  
Dependent Manner ◽  
First Time

Extracellular matrix (ECM) plays an important role in cell differentiation, growth, migration and apoptosis. Collagen is the most abundant protein familyin vivo, but its function has still not been clearly defined yet. Reactive oxygen species (ROS) have a central role in oxidative cell stress. Electron spin resonance (ESR) spectroscopy indicates that type I collagen could uniquely scavenge hydroxyl radicals in dose- and time-dependent manner; whereas BSA and gelatin (a denatured collagen) have no such an effect. However, the mechanism by which type I collagen scavenges hydroxyl radicals is different from that of GSH, a well-known free radical scavenger. Using a new method, two-dimensional FTIR correlation analysis, for the first time, we show that the order of functional group changes of type I collagen in this process is amide I earlier than amide II than amide III than –CH– thanν(C=O). The results indicates that the structure of the main chain of collagen changed first, followed by more residue groupν(C=O) exposed to hydroxyl radicals. The reaction with the carbonyl group in collagen causes the hydroxyl free radicals to be scavenged. Therefore, ECM can effectively scavenge ROS under normal physiological conditions. When the proteins of ECM were denatured in the same way as gelatin, they lost their function as a free radical scavenger. All of these results provide new insight into therapy or prevention of oxidative stress, apoptosis and ageing.

scholarly journals Induction of heme oxygenase-1 by hypoxia and free radicals in human dermal fibroblasts

2000 ◽  
Vol 278 (1) ◽  
pp. C92-C101 ◽  
Author(s):  
Maria V. Panchenko ◽  
Harrison W. Farber ◽  
Joseph H. Korn
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Heme Oxygenase ◽  
Iron Homeostasis ◽  
Dermal Fibroblasts ◽  
Skin Fibroblasts ◽  
Free Radical Scavengers ◽  
Radical Scavenger ◽  
Heme Oxygenase 1

Heme oxygenase-1 (HO-1) catalyzes the rate-limiting step in heme catabolism and presumably is involved in cellular iron homeostasis. It is induced by a variety of cellular stresses, including oxygen deprivation and free radical-mediated stress. We examined induction of HO-1 mRNA in skin fibroblasts and investigated the mechanism by which it occurs. Hypoxia did not appear to act via induction of oxygen free radicals: induction of HO-1 was not sensitive to the free radical scavenger GSH or other antioxidants. Moreover, hypoxia did not increase steady-state levels of free radicals generated by fibroblasts. In contrast, HO-1 induction by the oxidants, H2O2and carbonyl cyanide m-chlorophenylhydrazone (CCCP) was significantly attenuated in the presence of free radical scavengers. This correlated with increased levels of free radical production in fibroblasts treated with these oxidants. Iron depletion by desferrioxamine mesylate, a specific iron complexon, completely inhibited hypoxic stimulation of HO-1 but did not attenuate the effect of H2O2and CCCP on HO-1 mRNA. Addition of Fe2+, Fe3+, or holo-transferrin to fibroblasts increased levels of HO-1 mRNA. Treatment of cells with hypoxia, but not H2O2or an exogenous source of iron, significantly increased the half-life of HO-1 mRNA. The data suggest hypoxia regulates HO-1 gene expression by a specific posttranscriptional mechanism: stabilization of mRNA. Hypoxia has previously been shown to increase fibroblast collagen synthesis and is thought to play a role in pathogenesis of systemic sclerosis (SSc). Skin fibroblasts isolated from patients with SSc demonstrated significantly stronger induction of HO-1 by hypoxia than did fibroblasts from normal controls. We hypothesize that exposure of SSc fibroblasts to hypoxic conditions leads to in vivo selective proliferation of cells that adapt to hypoxia.

Ceria-Zirconia Antioxidant Nanoparticles Attenuate Hypoxia-Induced Acute Kidney Injury by Restoring Autophagy Flux and Alleviating Mitochondrial Damage

2020 ◽  
Vol 16 (7) ◽  
pp. 1144-1159
Author(s):  
Sang-Eun Hong ◽  
Jong Hun An ◽  
Seong-Lan Yu ◽  
Jaeku Kang ◽  
Chang Gyo Park ◽  
...  
Keyword(s):  
Acute Kidney Injury ◽  
Free Radical ◽  
Antioxidant Activities ◽  
Kidney Injury ◽  
Mitochondrial Damage ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Autophagy Flux ◽  
Novel Approach

Oxidative stress is one of the principal causes of hypoxia-induced kidney injury. The ceria nanoparticle (CNP) is known to exhibit free radical scavenger and catalytic activities. When zirconia is attached to CNPs (CZNPs), the ceria atom tends to remain in a Ce3+ form and its efficacy as a free radical scavenger thus increases. We determined the effectiveness of CNP and CZNP antioxidant activities against hypoxia-induced acute kidney injury (AKI) and observed that these nanoparticles suppress the apoptosis of hypoxic HK-2 cells by restoring autophagy flux and alleviating mitochondrial damage. In vivo experiments revealed that CZNPs effectively attenuate hypoxia-induced AKI by preserving renal structures and glomerulus function. These nanoparticles can successfully diffuse into HK-2 cells and effectively counteract reactive oxygen species (ROS) to block hypoxia-induced AKI. This suggests that these particles represent a novel approach to controlling this condition.

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