Some Biochemical Functions of Selenium in Animals and Man
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Thus there is considerable evidence for an essential role of selenium in many processes in the cell and a major challenge is to relate this biochemical knowledge to a potential for low dietary selenium to be involved in the development of diseases.It is difficult to relate determination of single,selenium-containing enzyme activities or total selenium content of blood to the many selenoenzymes in tissues of humans.However,in animal studies selenoenzyme activities in different tissues are very consistent and show some correlation with blood selenium concentrations.Thus in animals it is possible to correlate a particular blood selenium concentration with metabolic effects in specific tissues.Diets consumed by humans are much more variable than those consumed by animals in investigations of selenium status and there is little data to relate particular blood selenium concentrations to activities of selenoproteins in different organs.Thus, there is much circumstantial evidence,which relates to inadequate supply of dietary selenium to optimal health in human subjects.Further experiments are needed to relate to different dietary selenium intakes to health problems such as cancer and impaired immune function.This work is critically facilitated by detailed studies of selenium biochemistry and function in cell culture and experimental animals.
JRA is grateful to the Scottish Office Agriculture,Environment and Fisheries Department for financial support.We are grateful to our collaborators whose work has been extensively cited in the reference list.
KeywordsBrown Adipose Tissue Iodine Deficiency Selenium Deficiency Selenium Supplementation Selenium Status
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