Anti-oxidant defenses

Heffner JE, Repine JE (1989) Pulmonary strategies of anti-oxidant defense. Am Rev Respir Dis 140(2) 531-554. 

Selenium is an essential element for humans and is a constituent of selenoamino acids contained in selenoenzymes, such as glutathione peroxidases. This group of enzymes catalyzes the reduction of peroxides and thereby takes part in the anti-oxidative defense of the body. A severely low Se intake may cause heart disease (Keshan s disease). Therefore, possible adverse health effects are associated with a low intake of this element and justify the focus on the low percentile Se intake in the population. The food groups that contribute the most to the Se intake are meat (including offal) followed by bread and cereals, and fish, as shown in Figure 9.8. 

Accelerated Mice (SAM) line being characterized by accelerated rate of accumulation of senescence features and essential (approximately two-fold) shortening of lifespan in relation to the animals of the control line [99]. SAM mice are characterized by multiple defects in the system of anti-oxidant defense and increased level of chromosomal aberrations in the stem cells [99,100]. Every day use of camosine by the animals of this line (100 mg/kg body weight) results in deceleration (or reversion) of senescence, increase in average lifespan (approximately by 20%) as well as favored the exterior of the animals [101-103]. 

No gene coding for a plasmodial catalase has been found in the P. falciparum genome and it is doubtful that one exists. Although Plasmodium spp. lack catalase (and GSH peroxidases) their armamentarium of anti-oxidant defense mechanisms includes ... 

Sarkar A, Mukheijee B, Chatlerjee M (1995) Inhibition of 3 -methyl-4-dimethylaminoa-zobenzene-induced hepatocarcinogenesis in rat by dietary P-carotene changes in hepatic anti-oxidant defense enzyme levels. Int J Cancer 61(6) 799-805... 

As for iron, differences in redox potentials are relatively small between the major oxidation states of copper, that is, Cu(I) and Cu(II). This gives copper its main function as a cofactor in enzymatic reactions involving electron-transfer processes. In the human body, most of the copper (about 40%) is present in muscle tissue with significant amounts also present in the liver, brain, and skeleton. About 5% of the copper can be found in serum, of which 80-90% is present as ceruloplasmin. Ceruloplasmin in serum and hephaestin at the basolateral side of the mucosa ensure oxidation of circulating Fe to Fe for iron binding to transferrin. Unbound Fe is a major source of oxidative stress through Fenton/Haber-Weiss chemistry. Copper together with zinc is also a cofactor for superoxide dismutase, a key molecule in the anti-oxidant defense system of the body ]74]. 

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