Reactive oxygen species scavenger

Fullerene Cgo also functions efficiently as an antioxidant, actually being better than other lipid-soluble antioxidants at scavenging reactive oxygen species (ROS) (Wang et al., 1999). Water-soluble derivatives of C o, such as a poly-hydroxyl form, are able to function in the same respect in aqueous environments. 

The possibility to employ C60 as cytoprotective agents can be considered both one of the most promising applications and one of the most studied since the publication of the fundamental works of Dugan and coworkers, who analyzed fullerene capability of scavenging reactive oxygen species (ROS) (Dugan et al., 1996, 1997, 2000 Quick and Dugan, 2004 Ah et al., 2004). 

Leonard SS, Xia C, Jiang BH, Stinefelt B, Klandorf H, Harris GK, Shi X. 2003. Resveratrol scavenges reactive oxygen species and effects radical-induced cellular responses. Biochem Biophys Res Commun 309 1017-1026. 

Tea polyphenols have been shown to scavenge reactive oxygen species, such as superoxide radical, singlet oxygen, hydroxyl radical, nitric oxide, nitrogen dioxide, and peroxynitrite, which may play important roles in carcinogenesis. 

Amifostine is an organic thiophosphate cytoprotective agent that can reduce the toxicity of cisplatin. It binds to and thereby detoxifies reactive metabolites of cisplatin. It scavenges reactive oxygen species generated by exposure to cisplatin radiation. 

Factors scavenging reactive oxygen species Enzymes. Two types of enzymes exist to remove H2O2 within cells (Fig. 2) the haem protein CAT, present in most aerobic cells, which catalyses the degradation of H2O2 to triplet O2 and water (Eq. 

Ascorbic acid is able to scavenge reactive oxygen species as Oj " (Nishikimi 1975), HO (Bielski et al. 1975) and O2 (Bodannes and Chan 1979). On the... 

This category of antioxidants can be subdivided into water soluble and lipid soluble antioxidants. Nevertheless, they all act in a similar manner when scavenging reactive oxygen species. Radicals usually react with these antioxidants as a redox system, hence, the difference in reduction potentials of the species involved is a factor in determining how efficiently the reaction proceeds. An antioxidant can either react by donating an electron or a hydrogen atom to the radical, thus producing a stable compound and an antioxidant-derived radical (non-redox reactions can also occur, such as addition). 

Metallothioneins are implicated in scavenging reactive oxygen species. A relevant reaction is the oxidation of a Zn(Cys)2 domain which releases Zn ". Write a half-equation to show what happens during this transformation. 

More recently, non-sulfur fructosyl arginine, a Maillard reaction product, was isolated from AGE and was found to inhibit LDL oxidation (18), inhibit oxidized LDL-induced endothelial cell injury (18) and directly scavenging reactive oxygen species in cells and cell free systems (18, 19). 

The composition and content of the different tocopherol components in plant tissue vary considerably, ranging from extremely low levels found in potato tubers to high levels found in oil seeds. a-Tocopherol is the predominant form in photosynthetic tissues and is mainly localized in plastids. The particular enrichment in the chloroplast membranes is probably related to the ability of tocopherols to quench or to scavenge reactive oxygen species and lipid peroxy radicals by physical or chemical means. In this way, the photosynthetic apparatus can be protected from oxygen toxicity and lipid peroxidation. In nonphotosynthetic tissues, 7-tocopherol frequently predominates and can be involved in the prevention of autoxidation of polyunsaturated fatty acids. 

To scavenge reactive oxygen species, a well-known endogenous antioxidant, glutathione (GSH), was examined. 

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