scholarly journals Dynamics of reactive oxygen species generation in the presence of copper(II)-histidine complex and cysteine.

2013 ◽  
Vol 60 (4) ◽  
Author(s):  
Anna Ząbek-Adamska ◽  
Ryszard Drożdż ◽  
Jerzy W Naskalski
Keyword(s):  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Atmospheric Oxygen ◽  
Mercury Electrode ◽  
Reactive Oxygen Species Generation ◽  
Reaction Medium ◽  
Reactive Oxygen ◽  
Lag Phase ◽  
Oxygen Species ◽  
Ros Formation

Histidine-copper(II) complex (Cu-His2) is a form of bound copper necessary for cellular copper uptake. Due to the high affinity of histidine to copper(II) ions, the binding of copper(II) by histidine is considered a substantial part of plasma antioxidative defense. Also cysteine plays a role in the antioxidative system. However, we show here that in the presence of oxygen the histidine-copper(II) complex plus cysteine produces reactive oxygen species (ROS). Cysteine concentration was assayed using a thiol specific silver-mercury electrode. Hydrogen peroxide was assayed amperometrically using platinum electrode. ROS formation was followed by chemiluminescence of luminol-fluoresceine-enhanced system. Addition of cysteine to Cu-His2 solution at pH 7.4 in the presence of atmospheric oxygen initiates the synthesis of H2O2 and generation of ROS, which manifests as a burst of chemiluminescence. The reaction has two stages; in the first stage, cysteine is utilized for the synthesis of an unstable intermediary product which becomes a substrate for ROS formation. Anaerobic conditions inhibit ROS formation. Increased cysteine concentration enhances the lag phase of the oxidative burst without influencing the amount of ROS. The synthesis of ROS (measured by chemiluminescence) is proportional to the concentration of Cu-His2 employed. ROS production can be repetitively initiated by further additions of cysteine to the reaction medium. The study suggests that Cu-His2 catalyzes cysteine-dependent reduction of oxygen to superoxide employing an intermediary cysteine-copper(I) complex and enabling Fenton reaction with copper and hydrogen peroxide produced as a secondary product. In effect, Cu-His2 with cysteine may be a source of ROS in biological media.

Benzene metabolites enhance reactive oxygen species generation in HL60 human leukemia cells

1996 ◽  
Vol 15 (5) ◽  
pp. 422-427 ◽  
Author(s):  
Y. Shen ◽  
H-M. Shen ◽  
C-Y. Shi ◽  
C-N. Ong
Keyword(s):  
Reactive Oxygen Species ◽  
Lipid Peroxidation ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Leukemia Cells ◽  
Ros Generation ◽  
Human Leukemia ◽  
Ros Production ◽  
Oxygen Species ◽  
Ros Formation

Benzene is myelotoxic and leukemogenic in humans. The mechanisms leading to these effects, however have not been fully elucidated. One of the underlying mechanisms is believed to be the oxidative damage caused by its metabolites. A comparative study was undertaken to examine the relationships between reactive oxygen species (ROS) production, lipid peroxidation and subse quent cytotoxicity induced by five major benzene meta bolites. The generation of ROS by benzene metabolites was demonstrated by the significant and dose-dependent increase of intracellular ROS formation in HL60 human promyelocytic leukemia cells in vitro. 1,4-Benzoquinone (BQ) was found to be the most potent metabolite in induction of ROS formation, followed by 1,2,4-benzene triol (BT) and to a lesser extent, phenol (PH) and trans, trans-muconaldehyde (MD). No significant effect was observed when the cells were treated with trans, trans-muconic acid (MA). The enhancement of ROS production by BQ was effectively inhibited by the addition of catalase, deferoxamine (DFO) and dimethyl sulfoxide (DMSO), but unchanged by superoxide dismutase (SOD), suggest that hydrogen peroxide (H2O2) and hydroxyl radicals (OH.) are the two major forms of ROS involved. The results also demonstrate that the ability of benzene metabolites in enhancing ROS generation is closely correlated to their capacity in causing lipid peroxidation and subsequent cytotoxicity. These findings together with earlier parallel observations on DNA damage suggest that ROS play an important role in the mechanism of carcinogenesis induced by benzene metabolites.

Protocol of proceedings with Fusobacterium nucleatum and optimization of ABTS method for detection of reactive oxygen species

2020 ◽  
Vol 15 (4) ◽  
pp. 259-271
Author(s):  
Anna Kędziora ◽  
Monika Katarzyna Lesiów ◽  
Katarzyna Krupa ◽  
Agnieszka Korzeniowska-Kowal ◽  
Ryszard Adamski ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Free Radicals ◽  
Atmospheric Oxygen ◽  
Outer Membrane Proteins ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Fusobacterium Nucleatum ◽  
Oxygen Species

Aim: Characterization of the ability of Fusobacterium nucleatum DSM 15643 and DSM 20482 strains in the presence of Cu2+ and H2O2 to reactive oxygen species generation. Method: Spectrophotometric ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) method was used. Results: Determination of: MIC for Cu2+, H2O2 and ABTS; survivability of F. nucleatum under atmospheric oxygen exposure; the level and rate constants of free radicals production by the bacteria. Conclusion: F. nucleatum in the presence of Cu2+ and H2O2 is able to generate free radicals. Reactive oxygen species are produced mainly outside the bacterial cell, which suggests that outer membrane proteins may be involved in oxidative process.

Роль оксида азота в реализации антиоксидантного эффекта неопиатного аналога лей-энкефалина в сердце новорожденных белых крыс

2019 ◽  
pp. 61-64
Keyword(s):  
Reactive Oxygen Species ◽  
Reactive Oxygen Species Generation ◽  
Reactive Oxygen ◽  
Postnatal Period ◽  
Oxide System ◽  
No Synthase ◽  
Albino Rats ◽  
Oxygen Species ◽  
Control Parameters ◽  
Synthase Inhibitor

The eff ect of the non-opiate analog of leu-enkephalin (peptide NALE: Phe – D – Ala – Gly – Phe – Leu – Arg) on the reactive oxygen species generation in the heart of albino rats in the early postnatal period was studied. Peptide NALE was administered intraperitoneally in the dose of 100 μ/kg daily from 2 to 6 days of life. Reactive oxygen species generation was assessed by chemiluminescence in the heart homogenates of 7-day-old animals. Decreasing of reactive oxygen species generation nearly by 30 % and an increasing in antioxidant system activity by the 20-27 %, compared with the control parameters, were found. The antioxidant eff ect of peptide NALE is associated with the presence of the amino acid Arg in the structure of the peptide. An analogue of NALE peptide, devoid of Arg (peptide Phe – D – Ala – Gly – Phe – Leu – Gly), had a signifi cant lower antioxidant eff ect. The NO-synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) in the dose 50 mg/kg, administered with NALE peptide, reduced the severity of the NALE antioxidant eff ect. The results of the study suggest that the pronounced antioxidant eff ect of NALE peptide in the heart of albino rats, at least in part, is due to the interaction with the nitric oxide system.

Hydrogen peroxide-responsive AIE probe for imaging-guided organelle targeting and photodynamic cancer cell ablation

2021 ◽  
Author(s):  
Qian Wu ◽  
Youmei Li ◽  
Ying Li ◽  
Dong Wang ◽  
Ben Zhong Tang
Keyword(s):  
Reactive Oxygen Species ◽  
Hydrogen Peroxide ◽  
Cancer Cell ◽  
Reactive Oxygen ◽  
Living Cells ◽  
Oxygen Species ◽  
Cell Ablation ◽  
Selective Monitoring ◽  
Organelle Targeting

Hydrogen peroxide (H2O2), as one kind of key reactive oxygen species (ROS), is mainly produced endogenously primarily in the mitochondria. The selective monitoring of H2O2 in living cells is of...

Sign in / Sign up

Export Citation Format

Share Document