title: A cytochrome c-enhanced peroxidation reaction with potential use in screening dietary antioxidants.
abstract: Reactive oxygen species (ROS) that result from events such as cellular respiration can cause damage to biological molecules and tissues. A variety of endogenous and dietary antioxidants function in moderating the extent of oxidative damage in the body. In this report, a pro-oxidant system is presented as an assay for screening possible antioxidant activities of dietary factors. The assay reaction involves peroxidatic oxidation of the redox indicator N,N,N',N'-tetramethyl-1,4-phenylenediamine (TMPD). It is shown that the reaction rate is enhanced by up to 10-fold in the presence of cytochrome c (cyt c), a mitochondrial electron transport protein. The extent to which selected dietary antioxidant factors inhibit the cytochrome c-enhanced peroxidatic oxidation of TMPD is also reported. Considering the known pathological consequences of mitochondrial membrane disruption and cytochrome c release in the cell, this reaction and assay may be of pathological and therapeutic relevance.
authors.affiliation: Laboratory for Metabolic and Endocrine Research, K9600 Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6.
authors.forename: Suiping
authors.initials: S
authors.lastname: Zhou
authors.forename: Yu
authors.initials: Y
authors.lastname: Yao
authors.forename: Allan
authors.initials: A
authors.lastname: Davison
authors.forename: Amandio
authors.initials: A
authors.lastname: Vieira
mesh_terms: D000975:Antioxidants / Q000032:analysis* / Q000378:metabolism*; D045304:Cytochromes c / Q000032:analysis* / Q000378:metabolism*; D004032:Diet; D005638:Fruit / Q000378:metabolism*; D015227:Lipid Peroxidation / Q000502:physiology; D010084:Oxidation-Reduction; D010936:Plant Extracts / Q000032:analysis / Q000378:metabolism; D012639:Seeds / Q000378:metabolism; D013772:Tetramethylphenylenediamine / Q000032:analysis / Q000378:metabolism
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D045304:Cytochromes c; D013772:Tetramethylphenylenediamine