scholarly journals Baicalein protects tert-butyl hydroperoxide-induced hepatotoxicity dependent of reactive oxygen species removal

2017 ◽  
Vol 16 (6) ◽  
pp. 8392-8398
Author(s):  
Ya-Fang Wang ◽  
Zheng-Hai Tang ◽  
Ting Li ◽  
Xiao-Huang Xu ◽  
Xiuping Chen ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Butyl Hydroperoxide ◽  
Tert Butyl ◽  
Tert Butyl Hydroperoxide ◽  
Species Removal

Induction ofPseudomonas aeruginosafhpandfhpRby reactive oxygen species

2009 ◽  
Vol 55 (6) ◽  
pp. 657-663 ◽  
Author(s):  
Taija S. Koskenkorva-Frank ◽  
Pauli T. Kallio
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Promoter Activity ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Low Oxygen ◽  
Butyl Hydroperoxide ◽  
Tert Butyl Hydroperoxide ◽  
Oxygen Conditions

In Pseudomonas aeruginosa , flavohemoglobin (Fhp) and its cognate regulator FhpR (PA2665) form a protective regulatory circuit, which responds to reactive nitrogen species and is also capable of protecting cells against nitrosative stress. Recently, it has been shown that the expression of the fhp promoter is regulated not only by FhpR, but also by two new regulators, PA0779 and PA3697. It has also been suggested that the bacterial flavohemoglobins (flavoHbs) could play a crucial role in the protection of cells against reactive oxygen species (ROS). Therefore, the role and function of the Fhp/FhpR system during oxidative stress were studied by assessing the viability and membrane integrity of P. aeruginosa cells and by analyzing the promoter activities of fhp and fhpR upon exposure to paraquat, hydrogen peroxide, and tert-butyl hydroperoxide, under both aerobic and low-oxygen conditions. The results showed that under aerobic conditions, both fhp and fhpR promoters are induced by ROS generated by the stressors. Thus, the Fhp/FhpR system is implicated in the oxidative stress response. ROS-induced fhp promoter activity was dependent on FhpR, PA0779, and PA3697 regulators. Tert-butyl hydroperoxide-induced fhpR promoter activity was found to be highly repressed by PA0779, and FhpR showed negative autoregulation of its own promoter. Under low-oxygen conditions, the activity of the fhp promoter was not inducible by ROS, but fhpR promoter activity was induced by paraquat, and hydrogen peroxide was repressed in both cases by the regulators PA0779 and PA3697.

Interaction of insulin with methyl tert -butyl ether promotes molten globule-like state and production of reactive oxygen species

2015 ◽  
Vol 80 ◽  
pp. 610-614 ◽  
Author(s):  
Masoumeh Valipour ◽  
Parvaneh Maghami ◽  
Mehran Habibi-Rezaei ◽  
Mostafa Sadeghpour ◽  
Mohamad Ali Khademian ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Molten Globule ◽  
Reactive Oxygen ◽  
Methyl Tert Butyl Ether ◽  
Oxygen Species ◽  
Butyl Ether ◽  
Tert Butyl

scholarly journals Effects of the Nitrone Radical Scavengers PBN and S-PBN on In vivo Trapping of Reactive Oxygen Species after Traumatic Brain Injury in Rats

2001 ◽  
Vol 21 (11) ◽  
pp. 1259-1267 ◽  
Author(s):  
Niklas Marklund ◽  
Tommy Lewander ◽  
Fredrik Clausen ◽  
Lars Hillered
Keyword(s):  
Reactive Oxygen Species ◽  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Brain Tissue ◽  
Reactive Oxygen ◽  
Separate Experiment ◽  
Ros Production ◽  
Oxygen Species ◽  
Tert Butyl ◽  
Drug Concentrations

In previous studies, the authors showed that the nitrone radical scavenger α-phenyl-N- tert-butyl nitrone (PBN) and its sulfo-derivative, 2-sulfo-phenyl-N- tert-butyl nitrone (S-PBN), attenuated cognitive disturbance and reduced tissue damage after traumatic brain injury (TBI) in rats. In the current study, the production of reactive oxygen species (ROS) after TBI was monitored with microdialysis and the 4-hydroxybenzoic acid (4-HBA) trapping method. A single dose of PBN (30 mg/kg) or an equimolar dose of S-PBN (47 mg/kg) was administered intravenously 30 minutes before a controlled cortical contusion injury in rats. Plasma and brain tissue drug concentrations were analyzed at the end of the microdialysis experiment (3 hours after injury) and, in a separate experiment with S-PBN, at 30 and 60 minutes after injury. Traumatic brain injury caused a significant increase in ROS formation that lasted for 60 minutes after the injury as evidenced by increased 3,4-dihydroxybenzoic acid (3,4-DHBA) concentrations in the dialysate. PBN and S-PBN equally and significantly attenuated the posttraumatic increase in 3,4-DHBA formation. High PBN concentrations were found bilaterally in brain tissue up to 3 hours after injury. In contrast, S-PBN was rapidly cleared from the circulation and was not detectable in brain at 30 minutes after injury or at any later time point. The results suggest that scavenging of ROS after TBI may contribute to the neuroprotective properties observed with nitrone spin-trapping agents. S-PBN, which remained undetectable even in traumatized brain tissue, reduced ROS production to the same extent as PBN that readily crossed the blood–brain barrier. This finding supports an important role for ROS production at the blood–endothelial interface in TBI.

scholarly journals Antioxidant Activity of Silver-containing Bionanocompositions Based on Humic Substances in Cell Culture

2021 ◽  
Vol 10 (4) ◽  
pp. 46-53
Author(s):  
E. E. Buyko ◽  
M. V. Zykova ◽  
V. V. Ivanov ◽  
K. A. Bratishko ◽  
A. A. Ufandeev ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Culture ◽  
Antioxidant Activity ◽  
Wound Healing ◽  
Silver Nanoparticles ◽  
Humic Substances ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Butyl Hydroperoxide ◽  
Purulent Wounds

Introduction. Silver nanoparticles are promising agents for suppressing resistant strains of microorganisms and accelerating the purulent wounds healing. Oxidative stress disrupts normal wound healing processes, which leads to the formation of chronic non-healing wounds. Therefore, the determination of the ability of new wound healing agents to decrease the production of reactive oxygen species is a relevant task.Aim. The aim of the current study was to investigate the effect of silver-containing bionanocompositions based on humic substances on the basal and tert-butyl hydroperoxide-stimulated production of reactive oxygen species at the normal fibroblasts 3T3-L1 cell culture in vitro.Materials and methods. The study was carried out on 7 samples of initial humic substances and biomaterials with silver nanoparticles synthesized in the Laboratory of Natural Humic Systems, Faculty of Chemistry, Moscow State University named after M. V. Lomonosov. The intracellular production of reactive oxygen species was assessed using a 2,7-dichlorodihydrofluorescein diacetate fluorescent probe. Cells were cultured with samples for 24 h; tret-butyl hydroperoxide was used to stimulate the production of reactive oxygen species. Detection was performed fluorometrically using a microplate reader.Results and discussion. The most pronounced antioxidant activity was demonstrated by three samples of biomaterials with silver nanoparticles ultradispersed in humic substances matrices (CHS-AgNPs, CHP-AgNPs and CHE-AgNPs), which allows us to consider them as the most promising pharmaceutical agents for the treatment of purulent-inflammatory processes. The most probable mechanism of the high antioxidant activity of the studied biomaterials in relation to intracellular reactive oxygen species is the intrinsic activity of humic substances to bind reactive oxygen species, while silver nanoparticles in biomaterials catalyze the reduction processes of their interaction with reactive oxygen species.Conclusion. For the studied samples of biomaterials with silver nanoparticles ultradispersed in matrices of humic substances pronounced antioxidant activity was shown. Together with antibacterial properties, it makes it possible to consider them as potential agents for purulent wounds healing accelerating.

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