26 research outputs found
Effect of selenium-vitamin E injection in selenium-deficient dairy goats and kids on the Mexican plateau
Effect of copper, zinc and cadmium on the promoter of selenoprotein W in glial and myoblast cells
Rat selenoprotein W (SeW) promoter activity was investigated using different concentrations of cadmium, copper, and zinc. Two fragments (404 and 1265 bp) of the SeW promoter, containing a single metal response element (MRE), were ligated into the multiple cloning site of a pGL3-Basic reporter plasmid. The constructs were transfected into cultured C6 (rat glial) and L8 (myoblast) cells and promoter activity measured by means of luciferase reporter gene fused to the SeW promoter fragments in the reporter plasmid. With post-transfection exposure of these cell lines to these metals, copper and zinc, but not cadmium, significantly increased promoter activity of the unmutated 1265 bp (not 404 bp) construct (p<0.05) only in the C6 cells. Mutation of the MRE sequence abolished promoter response to metal exposure but did not eliminate promoter activity. The results suggest that SeW expression in glial cells can be increased on exposure to copper and zinc and that this response is dependent on the MRE sequence present in the SeW promoter
Selenoprotein W, Selenium and Glutathione Peroxidase in Rat and Sheep Brains and in Brain Cell Cultures
Low Molecular Weight Cadmium and Selenium Containing Proteins unlike Metallothionein in Animals
Diversion of mercury binding in rat tissues by selenium: A possible mechanism of protection
Selenium in Seafood Materials
Research interests in studying the biochemical nature of selenium have increased and the importance of this element as an essential micronutrient in many organisms has been well recognized. Selenium occurs in proteins in the form of the 21st amino acid, selenocysteine (SeCys or Sec). In this review, we describe the speciation analysis of the fish-specific selenoproteins and non-proteinous selenium compounds, and the nutritional bioavailability of selenium from seafood materials. Selenium is essential to fish and shellfish. The selenoproteomes (sets of SeCys-containing proteins) of fish are greater in number than those of mammals (25 selenoproteins in humans); at 30-37 selenoproteins, the selenoproteomes of fish are among the largest known. The same core selenoprotein families are found in mammals and fish. In addition, fish have several species-specific selenoproteins [fish 15 kDa selenoprotein-like protein (Fep15), selenoprotein J and selenoprotein L] that are missing in mammals. Actually, not only proteinous selenium species like selenomethionine (SeMet) and SeCys derivatives, but also many non-proteinous organic ones were detected in fish and shellfish samples. Although the selenium contents in seafood are higher than in terrestrial foodstuffs, little is known about the chemical forms of organoselenium species in seafood. The nutritional bioavailability of selenium from seafood appears to be dependent on the fish and shellfish species and/or place where they are produced; some seafood gives rise to a high bioavailability of selenium, which is comparable to that of wheat and beef. Fish and shellfish materials are major dietary sources of selenium for the Japanese population (~60% of daily intake). Seafood materials appear to contain nutritionally effective organoselenium compounds that have not yet been chemically identified