Many of these effects are due to proteins that contain Se as selenocysteine, a very effective redox catalyst at physiological pH. J.R. Arthur reviewed some of the more recently discovered functions of Se and effects of Se deficiency and how these may have implications for animal and human health. Se deficiency and disease Se deficiency, generally combined with vitamin E deficiency, is the cause of several degenerative diseases in animals. The most widely recognized problems are skeletal and cardiac myopathies, and liver necrosis.
Se deficiency can cause both male and female infertility, poor growth and exudative diathesis.
The exact relationship between this disease and Se has not been established and other factors must also be involved in its etiology. Along with these diseases, Se has been associated with fertility, immune function, thyroid hormone metabolism, drug metabolizing enzymes, heart disease, cancer and effects on mood and well being. These latter diseases and potential biological functions have been the topics of much current Se-related research. Subsequently, many attempts were made to associate Se deficiency disease with loss of cGSHPx activity. In particular, when combined with vitamin E deficiency, loss of cGSHPx activity would allow increased production of reactive oxygen species, with consequent damage to polyunsaturated fatty acids in membranes and essential proteins throughout the cell.