Nutrition selenium

Levander, O.A. 1983. Recent developments in selenium nutrition. Pages 147-162 in J. Weininger and C. Briggs (eds.). Nutrition Update, Vol. 1. John Wiley, New York. 

Although in humans only MsrBl is a selenoprotein, the depletion of selenium from the diet of mice led to increases in both R and S stereoisomers. This was not initially explained, yet a subsequent study has shown that small molecule selenols (organic selenocysteine homologues) could act as efficient electron donors in vitro for MsrA enzymes. ° This effect has only been shown in vitro, but the possibility that small molecular selenium reductants, or more likely that some selenoproteins that contain reduced selenols (in redox-active motifs) is quite intriguing. Several small selenoproteins do not have real roles and reside in nearly all subcompartments of the cell (mitochondria, ER) where electron donors for Msr enzymes are probably critical to maintain protein stability. Low selenium nutritional status would then have a significant impact on all methionine oxidation, as Future studies to address selenium nutrition and methionine oxidation could prove to be... 

Alexander, J. and Aaseth, J. (1985) Excretion of arsenic in rat bile A role of complexing ligands containing sulphur and selenium. Nutrition Research, 5(Suppl 1), S-515-S-519. 

Reddy, C.C. (1985) Effects of Inadequate Vitamin E and/or Selenium nutrition on enzymes associated with Hydroperoxide Metabolism. This Volume. 

Table II. Microsomal Heme Peroxidase Activity in Rats Fed Diets with Altered Vitamin E and/or Selenium Nutrition for 5 Weeks...

J. Zheng, W. Goessler, W. Kosmus, The chemical forms of selenium in selenium nutritional supplements an investigation by using HPLC/ICP MS and GF/AAS, Trace Elem. Electrol., 15 (1998), 70D75. 

K. L. Sutton, C. A. Ponce de Leon, K. L. Ackley, R. M. C. Sutton, A. M. Stalcup, J. A. Caruso, Development of chiral HPLC for selenoamino acids with ICP-MS detection application to selenium nutritional supplements, Analyst, 125 (2000), 281-286. 

Selenium has been recognized as an essential trace element in the diets of man and animals for many years (1) Another strong indication of its essentiality is the fact that it is an essential component of the enzyme glutathione peroxidase (2) Recently, scientists from the People s Republic of China demonstrated that Keshan disease (a cardiomyopathy in children) was correlated with low dietary selenium Intakes ( ) and could largely be prevented with supplementation Similarly, poor selenium nutrition in patients receiving total parenteral nutrition has been linked to muscular discomfort (4) and cardiomyopathy ( ) ... 

Levander, O. A. (1987). A global view of human selenium nutrition, Annu. Reit Nulr. 7, 227-250... 

Selenium-Requiring Enzymes Glutathione and Cancer Glutati ione and Aldehyde Metabolism Glutathione in the Glomerular Filtrate Selenium Nutrition Otiier Inoiganic Nutrients References Bibliography... 

Dietary levels of selenium and the individual s selenium nutritional status are the most important factors that influence the route and rate of selenium excretion. Selenium excretion in expired air is only significant when exposures to selenium are high. Rats injected subcutaneously with sodium selenite at doses of 2.2-5.4 mg selenium/kg excreted 41-62% of the administered selenium in exhaled air, whereas rats injected with sodium selenite at doses of 0.005-0.9 mg selenium/kg excreted only 0.2-11% of the administered selenium in expired air (McConnell and Roth 1966 Olson et al. 1963). As the amount of administered sodium selenite increased, the percent of the administered selenium excreted in the urine decreased (from approximately 22-33% of the administered selenium at doses of 0.005-0.9 mg selenium/kg to 3-14% of the administered selenium at doses of 3.1-5.4 mg selenium/kg) (McConnel and Roth 1966). Selenium in the feces was not measured in this study. Burk et al. (1972) found that as the dietary level of sodium selenite was increased, a larger proportion of an injected tracer dose of selenium (as sodium selenite) was excreted. At a dietary level of 0.005 mg selenium/kg, approximately 60% of the injected selenium had been excreted in the first 35 days following administration. At a dietary level of 0.05 mg selenium/kg, over 94% of the injected selenium had been excreted over the same period of time. 

Populations living in the western United States in areas eating produce grown in highly seleniferous soils could be at greater risk of adverse health effects from additional environmental exposure to selenium if their selenium nutritional status is already high (see Section 6.6). 

Gonzalez MJ, Rodriguez JR. 1988. Inhibition of sarcoma tumorigenesis in Balb/C mice by supplemented selenium. Nutrition Reports International 37(l) 41-46. 

Olson, R.E. Introductory remarks Interrelationships among vitamin E, coenzyme Q, and selenium. Nutrition Symp. Fed. Proc. 24, 55-57 (1965)... 

Mercury Toxicity Reduced by Selenium," Nutrition Reviews, Vol. 31,1973, p. 25. 

DEFICIENCY SYMPTOMS. There are no clear-cut signs or symptoms which indicate when people are mildly to moderately deficient in selenium. However, many tests on diverse species of animals and man have shown that blood and tissue levels of selenium are in most cases accurate reflections of the selenium nutritional status. But the interpretation of laboratory findings and the diagnosis of selenium deficiency are strictly jobs for health professionals, even though certain laboratories may analyze specimens for lay persons. Henc e, the information which follows is presented so that the patient and his or her doctor might consider whether such tests are advisable. 

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