Selenium immune system

Selenium is an essential trace element in the human body. This nutrient is an important part of antioxidant enzymes that protect cells against the effects of free radicals that are produced during normal oxygen metabolism. Selenium is also essential for normal functioning of immune system and thyroid gland. 

Undemutrition during fetal and early life impacts upon the development of the immune organs and appears to diminish cellular immunity and increase the risk of atopic disorders during childhood (Langley-Evans and Carrington 2006). The references confirm that many food components have a beneficial impact on various elements of the immune system. Proteins, some fats, vitamins (A, B6, E, and folic acid), macro- and microelements (zinc, iron, selenium, and copper), and certain bacteria (probiotic bacteria), for example, have a considerable effect on the immune system. 

R. C. McKenzie, J. R. Arthur, S. Miller, T. S. Rafferty, G. J. Beckett, Selenium and the immune system, in H. Hill (ed.), Nutrition and Immune Function, CABI/Nutrition Society, Wallingford (2002), pp. 229D250. 

In contrast to arsenic, trace concentrations of selenium are essential for human and animal health. Until the late 1980s, the only known metabolic role for selenium in mammals was as a component of the enzyme glutathione peroxidase (GSH-Px), an anti-oxidant that prevents cell degeneration. There is now growing evidence, however, that a seleno-enzyme is involved in the synthesis of thyroid hormones (Arthur and Beckett, 1989 G. F. Combs and S. B. Combs, 1986). Selenium dehciency has been linked to cancer, AIDS, heart disease, muscular dystrophy, multiple sclerosis, osteoarthropathy, immune system and reproductive disorders in humans, and white muscle disease in animals (Levander,... 

Tmmiinostimulants are defined as substances which stimulate immunological responses and improve a weakened immune system. They include interferon, thymus factor, interleukins, extracts of microorganisms, chemically defined substances (e.g. levamisole, selenium, zinc) and plant-derived substances (extracts from Phyl-lanthus, Bupleurum, Glycyrrhiza, Schizandra, etc.), (s. pp 705, 868)... 

The development, maintenance, and optimal functioning of the immune system are dependent on balanced and adequate nutrition. However, either a deficiency or an excess of a number of nutrients can have adverse effects. The nutrients with the most pronounced effects in humans include amount and type of dietary fatty acids (FAs), protein energy malnutrition, vitamins A, B6, B12, C, and E, and minerals including zinc, copper, selenium, and iron. Multiple rather than single nutrient deficiencies... 

As selenium can enhance some immune system functions, selenium may have a normal physiological function in the immune system. This is supported by an 8-week study in which treatment of mice with selenium as sodium selenite (0.33 mg selenium/kg/day, dietary) resulted in enhanced ability of cytotoxic T-lymphocytes to destroy tumor cells (Kiremidjian-Schumacher et al. 1992). 

Spallholz JE, Boylan LM, Larsen HS. 1990. Advances in understanding selenium s role in the immune system. Ann N Y Acad Sci 587 123-139. 

Not only arsenic, cadmium, lead, mercury, nickel, aluminum, molybdenum, and bromine, but also zinc, copper and selenium are uniformly toxic to the immune system, although the ultimate effect depends on the species of animals studied and the route and mode of administration. An important feature of inorganic toxicity is the observation that in animals, some metals affect the immune system at doses that are unaccompanied by other clinical manifestations of toxicity. A similar effect also occurs in man (Chowdhury and Chandra 1991)... 

Spallholz, J.E. 1988. Selenium and glutathione peroxidase essential nutrient and antioxidant component of the immune system, in Antioxidant Nutrients and Immune Functions, Phillips, M. and Tengerdy, R.P., Eds., Plenum Press, New York, 145. 

Ethyl alcohol is found in alcoholic beverages and is a known teratogenic material, which is the reason doctors tell pregnant women not to drink alcohol. When a mother drinks, the unborn child drinks as well. Ethyl alcohol causes growth failure and impaired brain development. Unborn children exposed to alcohol may suffer the effects of Eetal Alcohol Syndrome when they are bom. Symptoms of Fetal Alcohol Syndrome include sleep disturbance, jitteriness, a higher incidence of impaired vision and hearing, lack of motor coordination, balance problems, abnormal thyroid function, and a decrease in immune system effectiveness. Additional teratogens include heavy metals, methyl mercury, mercury salts, lead, thallium, selenium, penicillin, tetracyclines, excess Vitamin A, and carbon dioxide. 

Selenium affects all components of the immune system and is necessary for its optimum performance. The immune responses in rats supplemented with Se has been studied and the oncogenic characteristics of Se examined [23]. In general, a Se deficiency appears to result in immune suppression, while low-dosage supplementation results in augmentation and/or restoration of immunological functions [24]. 

Vitamin E and selenium have roles in the immune system and protect against heavy metal toxicity. Other mutual functions and effects of deficiency in farm animals are discussed in the section on vitamin E (see pp. 81-86). 

Selenium (Se) 2 mg Used in the immune system, health of heart and pancreas... 

Scientists are now exploring the interactions between these and other factors that affect immunity. For example, there is evidence that the production of optimal immunity requires ample amounts of dietary selenium, zinc, vitamin A, and vitamin C but only moderate amounts of dietary calories and proteins. Too little or too much of the latter nutrients may impair the functioning of the body s defense system. Hence, it should be possible in the near future to promote optimal functioning of the immune system by a balanced program of dietary measures, immunizations, medical treatment, and psychological counseling. 

One way that selenium appears to act is as a non-specific stimulant of immune competent tissues and cells contributing to its anti-inflammatory, immunopotentiation and carcinostatic attributes. Additional data suggests other effects of Se upon cells of the immune system perhaps independent of GSHPx activity such as ubiquinone biosynthesis, (Coenz3one Q 10) which in turn affects host-defense mechanisms (Frost, 1975). A third possibility to explain the effects attributed to Se above is to propose that increases in levels of the selenium dependent enzyme glutathione peroxidase and perhaps other specific selenium-dependent functions in lymphocytes and macrophages is the reason for immunoenhancement. This subject has been addressed by Schauzer (1979) and is amplified here by the author. 

Human selenium supplementation (e.g., 200 pg/ day), even in apparently selenium-replete individuals receiving a diet providing >120 pg Se/day, was able to stimulate the proliferation of activated T cells of the immune system. It eHcited an enhanced response to antigen stimulation, an enhanced ability to generate cytotoxic lymphocytes, an enhanced ability to destroy tumor cells, and increased natural killer cell activity. Growth-regulatory interleukin-2 receptors on the surface of activated lymphocytes and natural killer cells became upregulated. 

Arthur JR, McKenzie RC, and Beckett GJ (2003) Selenium in the immune system. Journal of Nutrition 133 1457S-1459S. 

Selenium is a significant component of the enzymatic system of the glutafion for antioxidant protection. It is included in the composition of 200 enzymes engaged in different biochemical reactions, demonstrates the immune-tropic, antiteratogenic and anticancer properties, betters the functional state of muscles, especially myocarditis, and takes part in hormones synthesis of the thyroid gland. Selenium s deficit in soil is the cause of hearth deficiency in endemic zones. 

Phosphorus, vitamin D, and calcium are all needed for bone health (Huth et al., 2006) and selenium has a role in the immune and antioxidant systems and in DNA synthesis and repair. Zinc is necessary for DNA repair, cell growth, gene expression, and is an essential part of some enzymes and metalloproteins. Magnesium has been implicated in the prevention of CVDs (Haug et al., 2007). For example, it is known that calcium, phosphorus, and magnesium may mediate beneficial effects on... 

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