Oxidant stress during inflammation: anti-inflammatory effects of antioxidants

Abstract

Local oxidative changes have been investigated during granulomatous inflammation in the rat. Lipid peroxidation occurred independently of the prostaglandin biosynthetic pathways in the kaolin granuloma pouch model. Elevated levels of malonaldehyde, The monitor of lipid peroxidation, were found in the plasma and livers of rats with a remote localized inflammation. The hepatic antioxidant capacity of these rats was markedly reduced, while aminopyrine metabolism was impaired, as reflected by the increased half-life of this drug. The aminopyrine half-life was longer in rats with a stronger inflammatory response. Local administration of free radical scavengers and antioxidants inhibited granuloma formation depending on the type of scavenger used. Thus scavengers of superoxide and hydroxyl radicals were ineffective as anti-inflammatory agents, whereas a scavenger of hydrogen peroxide and two lipid antioxidants markedly inhibited granuloma formation. The results indicate that several states of reduced oxygen and lipid peroxides are involved in the inflammatory response, and that the oxidative events are not limited to the inflamed site.

Hormone-mediated down-regulation of hepatic glutathione synthesis in the rat.

“…Hepatic GSH levels fall after stressful conditions such as shock, fasting, inflammation, and exhaustive exercise (3)(4)(5)(6)(7)(8)(9). Increased hepatic GSH efflux is at least partly responsible for the fall in liver GSH in fasting and exhaustive exercise (6,7).…”

Bioactive compounds in Magnifera indica demonstrates dose-dependent anti- inflammatory effects

“…The inhibitory effect of these compounds on the cellular phases of inflammation was attributed to the suppression of migration of leukocyte to the site of injury [23] .This effect may have resulted from the reduction in the release of chemoattractants or in the ability of white blood cells to respond to these chemical substances [23][24][25] .Therefore, the ability of MI to reduce the acute inflammation induced by carrageenin, suggest that it possesses phytochemical active compounds that could inhibit the migration of white blood cells to the site of inflammation by majorly by preventing leukocyte adherence, which is therate limiting step to the triggering actions of mediators of acute inflammation. It is well established in the literature that redness, loss of function and oedema formation are some of the cardinal signs of inflammation [26] .…”

The essentiality of sulfur is closely related to nitrogen metabolism: a clue to hyperhomocysteinaemia

“…There is no doubt that GSH is centrally involved in the adaptive responses to stressful stimuli. GSH is indeed implicated in the synthesis of leucotrienes (Anderson et al 1982), contributes to promote lymphocyte (Dröge et al 1991) and anti-inflammatory (Bragt & Bonta, 1980) activities, to neutralise hydrogen organic peroxides (Uhlig & Wendel, 1992) and to scavenge potentially toxic heterologous products (Meister & Anderson, 1983;Beutler, 1989). Assuming that an unaltered level of any metabolite results from the balance between synthesis and consumption rates, the increased demand for molecules mediating the adaptive responses to inflammation implies increased rates of production.…”