Reactive oxygen and nitrogen species (ROS/RNS) have been widely implicated in the ageing process and various approaches exist for monitoring these species in biological tissues. These approaches at present are limited to monitoring either a single pro-oxidant species or total pro-oxidant levels and therefore provide limited insight into the range of pro-oxidant species and their relative propor...

In the presence of transition metal ions and peroxides, polyphenols, well-known dietary antioxidants, can act as pro-oxidants. We investigated the effect of 13 polyphenols and their metabolites on oxidative degradation of deoxyribose by an •OH generating Fenton system (Fe2+-ethylenediaminetetraacetic acid (EDTA)-H₂O₂). The relationship between phenolics pro-oxidant/anti-oxidant effects and thei...

The objective of the study was to evaluate oxidative stress (OS) status in subjects with different cardiovascular risk factors. With this in mind, we have studied three models of high cardiovascular risk: hypertension (HT) with and without metabolic syndrome, familial hypercholesterolemia (FH) and familial combined hyperlipidemia (FCH) with and without insulin resistance. Oxidative stress marke...

We have analyzed the anti- or pro-oxidant effects of the flavonoid quercetin (QU) by evaluating, in U937 cell line, hydrogen peroxide (H(2)O(2)), superoxide anion reduced glutathione (GSH) content, mitochondrial membrane potential, DNA content, phosphatidylserine exposure on the outer face of the plasma membrane and cell viability. Polychromatic flow cytometry was used to evaluate in the same c...

Immune system functioning and maintenance entails costs which may limit investment into other processes such as reproduction. Yet, the proximate mechanisms and 'currencies' mediating the costs of immune responses remain elusive. In vertebrates, up-regulation of the innate immune system is associated with rapid phagocytic production of pro-oxidant molecules (so-called 'oxidative burst' responses...

Haem oxygenase-1 (HO-1) is a highly inducible stress protein that removes haem from cells with the release of biliverdin, carbon monoxide and low-molecular-mass iron (LMrFe). Several antioxidant functions have been ascribed to HO; its induction is considered to be a protective event. However, LMrFe produced during haem catabolism might elicit a pro-oxidant response, with deleterious consequence...