Glutathione peroxidase deficiency

P9. Perona, G., Guidi, G. C., Piga, A., Cellerino, R., Milani, G., Colautti, P., Moschini, G., and Stievano, B. M Neonatal erythrocyte glutathione peroxidase deficiency as a consequence of selenium imbalance during pregnancy. Br. J. Haematol. 42,567-574 (1979). 

Hemolytic anemia can occur in patients with glucose-6-phosphate dehydrogenase deficiency or erythrocjde glutathione peroxidase deficiency (SED-9, 128) (27-29). Whether these reports have anything more than anecdotal value (SEDA-17, 97) is not known. 

Necheles TF, Steinberg MH, Cameron D. Erythrocyte glutathione-peroxidase deficiency. Br J Haematol 1970 19(5) 605-12. 

Since glutathione peroxidase deficiency could predispose to severe reactions such as pancreatic or hepatic failure in children, screening for such deficiency might prove useful (SEDA-17, 72). 

Gondo H, Ideguchi H, Hayashi S, Shibuya T. Acute hemolysis in glutathione peroxidase deficiency. Int J Hematol 1992 55 215-18. 

Forgione, M.A.,Weiss, N., Heydrick,S., Cap,A., Klings,E.S., Bierl, C., Eherhardt, R.T., Father, H.W., and Loscalzo, J. (2002) Cellular Glutathione Peroxidase Deficiency and Endothelial Dysfunction, Am. J. Physiol. Circ. Physiol. 282, H1255-H1261. 

Stopford, W., Donovan, D. H., Abou-Donia, M. B., and Menzel, D. B., 1976, Glutathione peroxidase deficiency and mercury allergy Amelioration with selenium supplementation, in Proc. Symp. on Selenium-Tellurium in the Environ, pp. 105-112, Industrial Health Foundation Inc., 5231 Centre Ave., Pittsburg, Pennsylvania. 

In 1956 selenium was identified (123) as an essential micronutrient iu nutrition. In conjunction with vitamin E, selenium is effective iu the prevention of muscular dystrophy iu animals. Sodium selenite is adrninistered to prevent exudative diathesis iu chicks, a condition iu which fluid leaks out of the tissues white muscle disease iu sheep and infertility iu ewes (see Eeed ADDITIVES). Selenium lessens the iacidence of pneumonia iu lambs and of premature, weak, and stillborn calves controls hepatosis dietetica iu pigs and decreases muscular inflammation iu horses. White muscle disease, widespread iu sheep and cattle of the selenium-deficient areas of New Zealand and the United States, is insignificant iu high selenium soil areas. The supplementation of animal feeds with selenium was approved by the U.S. EDA iu 1974 (see Eeed additives). Much of selenium s metaboHc activity results from its involvement iu the selenoproteia enzyme, glutathione peroxidase. 

The free-radical defence mechanisms utilized by the brain are similar to those found in other tissues. The enzymes SOD, catalase, glutathione peroxidase, and the typical radical scavengers, ascorbate, vitamin E and vitamin A are present in the brain, as they are in peripheral tissues. However, the brain may actually be slightly deficient in some of these defence mechanisms when compared to the amounts present in other tissues. 

Selenium is required, but levels must fall into a narrow window. Both deficiency and toxicity symptoms occur. The element is also used therapeutically in cancer treatment. It is the co-factor of the enzyme glutathione peroxidase which is thought to play an important role in oxygen toxicity. The determination of Se in blood or serum is not easy, as many incorrect, inaccurate and imprecise methods have been published (Magee and James 1994). A suggested procedure for Se in body fluids is based on GF-AAS (Thomassen et al. 1994)- For tissues SS-AAS may be used (Fler-ber 1994a). Recent developments by Turner et al. (1999) show that LC-ICP-MS is sensitive and reproducible at low levels. 

Seleninm in this form is present in three enzymes glutathione peroxidase, iodothyronine deiodinase and thio-redoxin rednctase. Deficiency of selenium therefore decreases the activity of these three enzymes and resnlts, at least in experimental animals, in liver necrosis and mns-cnlar dystrophy. In hnmans, it is known to be a canse of a particnlar form of cardiomyopathy known as Keshan disease which affects children and women. This cardiomyopathy was first described in China in 1979. It is also considered that a deficiency of selenium is a risk factor for cancer. 

Selenium 6-12 mg 50-200 ng Glutathione peroxidase, interaction with heavy metals inhibitory effect on cancer Endemic cardiomyopathy, conditioned by Se deficiency muscle weakness Known in parts of China... 

Selenium deficiency has been described in patients receiving long-term selenium-free total parenteral nutrition. Myopathy and abnormal glutathione peroxidase concentrations are most... 

Also, selenium-dependent glutathione peroxidase activity has been shown to be reduced in selenium-deficient rats (C. Reddy, ( li). Selenium appears to inhibit both the initiation and promotion phases of carcinogenesis (Milner,... 

Table V. Effects of Vitamin E and/or Selenium Deficiency on Non-Se-Glutathione Peroxidase Activity...

Although glutathione is specifically decreased in kwashiorkor, blood levels of selenium-dependent glutathione peroxidase (a scavenger of peroxides) and vitamins A, C, and E (all members of the antioxidant machinery) are lower in both kwashiorkor and marasmus (Ashour et al., 1999). Why then are marasmic children, also deficient in some antioxidants, spared the oxidative stress Does a weakened antioxidant defense manifest as a serious threat only in the presence of pro-oxidant activities of the type encountered in kwashiorkor What is a possible trigger for the increase in free radicals, and how might this account for some of the phenotypic alterations in kwashiorkor ... 

In addition to proteins and calories, the patients with PEM must be replenished with respect to vitamins and micronutrients especially to enhance antioxidant status. Due to heavy vitamin A losses that occur during infections and PEM, vitamin A supplements are necessary to prevent blindness. Selenium, zinc, manganese, and cobalt are important micronutrients deficient in patients with PEM and therefore need to be replaced. These micronutrients play a vital role in the function of several enzymes (e.g., selenium in glutathione peroxidase). Iron must be excluded from the diet in the initial stage since early administration increases the risk of free-radical production and infection. 

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