Review article                                                                                         UDC: 616.441-085:546.23                                                                                                            doi:10.5633/amm.2015.0109

  

 

SELENIUM SUBSTITUTION – EFFECT ON THYROID FUNCTION

Milica Pešić^1,2, Danijela Radojković^1,2

Clinic of Endocrinology, Clinical Center Niš, Serbia¹

University of Niš, Faculty of Medicine, Niš, Serbia²

 

                         Contact: Milica Pešić
                        Clinic of Endocrinology, Clinical Center Niš, Serbia
                        Bul. Zorana Đinđića 48, 18000 Niš
                        E mail: mimapesic@gmail.com

The understanding of the essential role of selenium (Se) in thyroid hormone synthesis, metabolism and action, as well as normal thyroid function, increased during the past decades. The thyroid gland is among the human tissues with the highest Se content per mas unit, similar to other endocrine organs and brain.

 Biological actions of Se are mediated, in most cases, through the expression of at least 30 selenoproteins coded by 25 selenoprotein genes in the human. Via the selenoproteins, selenium can influence the cell function through antioxidant activites, modifying redox status and thyroid hormone synthesis and metabolism. Selenoproteins iodothyronine deiodinases are present in most tissues and have a role to increase the production of bioactive tri-iodothyronine.

Futhermore, Se has been shown to be important in the regulation of immune function. Se deficiency is accompained by the loss of immune competence. The links between Se deficiency, altered immune function and inflamation have prompted studies in humans to examine if Se suplementation can modify auto-antibodies production in patients with chronic autoimmune thyroiditis. Until now, several randomised prospective clinical trials have been performed in patients with established chronic autoimmune thyrioditis. The clinical endpoint of each study was the decrease in TPO antibodies concentration after 3-12 months of treatment. Ussualy, the dosage of daily Se supplementation was 200µg. Selenium suplemetation had no significant effect on the concentration of TSH or thyroid hormone concentrations. These studies indicate that Se treatment result in reduced inflammatory activity, but it does not cure chronc autoimmune process. Acta Medica Medianae 2015;54(1): 56-59.

 

Key words: thyroid gland, trace element, selenium