Stimulation of neutrophils with membrane perturbing agents causes an increase in oxygen consumption concomitant with the production of superoxide and hydroxyl radicals and hydrogen peroxide (HzOz). A plasma membrane-bound NADPH oxidase which is inactive in resting neutrophils has been implicated in the production of these radicals [ 1,2]. Purified NADPH oxidase has recently been shown to produc...

The discovery that macrophages metabolize ethanol to acetate in vitro may be of importance in understanding the pathogenesis of ethanol-induced tissue damage (1) . When expressed per unit wet weight, the rate of metabolism ofethanol by these cells is comparable to that by hepatocytes (2) . Studies of human and murine macrophages derived from various tissues have revealed that ethanol oxidation ...

The aim of this study was to assess the ability of different wines – a sweet red, a dry red, a sweet white, and a dry white – to scavenge the stable 1,1’-diphenyl-2-picryl-hydrazyl radical (DPPH.) and to determine their phenolic composition. Both red wines contained, apart from anthocyanins, also higher concentration of total phenolics, tartaric esters, and flavonols than the two white wines. A...

Mitochondria were isolated from skin fibroblast cultures derived from healthy individuals (controls) and from a group patients with complex I (NADH-CoQ reductase) deficiency of the mitochondrial respiratory chain. The complex I deficient patients included those with fatal infantile lactic acidosis (FILA), cardiomyopathy with cataracts (CC), hepatopathy with tubulopathy (HT), Leigh’s disease (LD...

There has been considerable controversy regarding the role of oxygen free radicals as important mediators of cell damage in reperfused myocardium. This controversy regards whether superoxide and hydroxyl free radicals are generated on reperfusion and if these radicals actually cause impaired contractile function. In this study, EPR studies using the spin trap 5,5-dimethyl-1-pyroline-n-oxide (DM...

The alcoholic extract of the shoot of H. perforatum shows strong antioxidant property. It possesses the iron chelation property with more affinity to the ferrous form. It has scavenging property for both superoxide and for hydroxyl radicals but the response is more towards the superoxide radicals. Thus in addition to the anti-depressant property it has strong antioxidant property also.

1. Oxygen radicals in biological systems and the importance of iron Oxygen radicals can be either organic or inorganic. The organic radicals such as the peroxy (ROO') and alkoxy (RO') are those derived from complex molecules like the polyunsaturated fatty acids. The inorganic oxygen radicals are the superoxide radical (O,-*) and the hydroxyl radical (OH'). Formation of the highly reactive hydro...

The mechanism of tissue and cell injury in ischaemic bowel necrosis is unclear. The present study investigated the role of oxygen derived free radicals in the development of bowel necrosis using injections of platelet activating factor (PAF) into the mesenteric vasculature. Animals were pretreated with allopurinol or superoxide dismutase together with catalase, before administration of PAF. Sup...

Superoxide production by stimulated neutrophils and by preparations of NADPH oxidase has consistently been measured by an indirect method utilising the reduction of cytochrome c by superoxide radicals [4]. This reduction is inhibited by superoxide dismutase. EPR spectroscopy using the technique of spin trapping has been used to identify superoxide radicals formed by photo-irradiated spinach chl...