An Investigation of the Succination of the Selenoproteins Thioredoxin Reductase and Glutathione Peroxidase Semantic Scholar Selenocysteine muscle pain ** **A lack of selenium cause muscle pain mechanism of action.** Selenium exerts its biological functions via molecules called selenoproteins which contain the amino acid cysteine with Glutathione and the Cofactors Selenium and male infertility Seleniumfacts.com