Reactive Oxygen Species and Their Contribution to Pathology in Down Syndrome

Antioxidant status and glutathione metabolism in peripheral blood mononuclear cells from patients with chronic hepatitis C

“…Despite activation of GSH biosynthesis, GSH remain within or below normal values, indicating increased GSH turnover. Oxidative stress may affect the efficiency of the effector mechanisms of the immune response (39), and it has also been shown to make cells more susceptible to apoptosis (46). It is possible, therefore, that oxidative stress in lymphoid cells may impair the antiviral immune response, thus facilitating chronicity of HCV infection.…”

Contents and Uptake Rates of Mn, Fe, Co, Zn, and Se in Se-Deficient Rat Liver Cell Fractions

“…It is therefore thought that Se interrupts the formation of the hydroxyl radical (·OH) from H2O2 through Harber-Weiss and/or Fenton reactions. 3,4 In other words, Se plays numerous protective roles against oxidative injury, including the peroxidation of membrane lipids and the degeneration of DNA and/or proteins.…”

Nutritional supplementation in Down syndrome: theoretical considerations and current status

“…However, the 50% increase in activity of SOD is much higher than the percentage increase usually reported in activity of GSH-Px 6,7,16,32,33 . De Haan and colleagues 35 reported a two-fold elevation in the SOD:GSH-Px ratio measured in a number of organs of aborted fetuses with DS compared with control fetuses. These authors also showed that cells with a high SOD:GSH-Px ratio are more likely to undergo apoptosis when challenged with hydrogen peroxide, which supports the findings of Busciglio and Yankner 24 cited earlier.…”

“…De Haan and colleagues 35 have carried out several studies suggesting that increased oxidative stress could be implicated in ageing. They found (1) a significant increase in the SOD:GSH-Px ratio (p<0.005) and susceptibility to lipid peroxidation (p<0.005) in normal mouse brain during ageing, (2) that cultured murine cells which have been transfected to have an increased SOD:GSH-Px ratio showed the characteristic features of senescence, (3) that normal mouse cells exposed to hydrogen peroxide in culture also showed features of senescence, and (4) that cells derived from children with DS showed features of senescence which were not seen in cells from age-matched control children.…”