Selenium, selenoproteins and cancer of the thyroid

Selenium, Iodine and Iron–Essential Trace Elements for Thyroid Hormone Synthesis and Metabolism

“…Thus, measures to improve nutritional I intake should be accompanied by adjusted increased nutritional Se (and Fe) supply in order to secure regular thyroid function and to avoid local adverse effects (such as oxidative damage, inflammation, fibrosis) of (too) high I availability for the angiofollicular units. Disbalances between trace element supply, local I utilization, TH synthesis and secretion have been observed under conditions of (genetically caused) congenital hypothyroidism, various autoimmune thyroid disease conditions and for thyroid cancer, both in humans but more so in appropriate animal experimental models mimicking such disease conditions [ 46 , 77 , 124 ]. The thoughtful translation of available knowledge gained from molecular, biochemical, in vitro and in vivo animal experimental studies to the human clinical practice still needs to be intensified.…”

“…TG is the main protein produced by follicles, and due to its enormous homodimer size (2 × 330,000 kDa), complex glycoprotein structure, secretion, deposition, polymerization and mobilization, processes in the follicular colloid require a battery of quality control mechanisms, including those exerted by members of the endoplasmic-reticulum-resident selenoproteins [ 76 ] typically involved in ribosomal biosynthesis and the posttranslational modification of proteins. Currently, it is not yet clear which of the selenoproteins are crucial for proper TG biosynthesis and whether their inadequate expression or function in the angio-follicular units of the thyroid gland may contribute to the development or perpetuation of autoimmune thyroid diseases or thyroid cancer [ 77 ]. In sections of ‘normal’ human thyroid tissue, adjacent to surgically resected tumor tissue GPx1, SelM, SelS are highly expressed at the protein level; pGPx (GPX3) and SELENOP were even found in the colloid lumen, while DIO2 signals were mainly located in the microvascular system and no DIO3 expression has been reported in thyroid glands.…”

The emerging role of neutrophil extracellular traps in endometritis

“…Selenium (Se) is a non-metallic trace element that has important effects on human and animal bodies. It has been reported to exhibit anti-tumor, anti-heavy metal, anti-virus, anti-oxidation, and enhancing immunity effects ( 49 , 50 ). Recent studies demonstrated selenium could inhibit LPS-induced endometritis in mice ( 51 ).…”

Evaluation of Selenomethionine Entrapped in Nanoparticles for Oral Supplementation Using In Vitro, Ex Vivo and In Vivo Models

“…Moreover, Se is a micronutrient with potential pharmaceutical application in aiding treatment or the prevention of specific diseases, including cardiovascular disorders [ 4 , 5 ], thyroid dysfunction [ 6 , 7 ] and neurodegenerative diseases [ 8 ]. Subtoxic plasma levels of selenium may also have potential in cancer therapy [ 2 , 9 , 10 , 11 ]. Taking all these potential medical applications into consideration, the range of preventative or therapeutic dose levels of SeMet following oral administration is thought to be narrow (60–70 μg/day) [ 12 ], which makes clinical oral supplementation difficult.…”

“…Regarding deficiency, low serum Se levels are linked to a higher risk of developing several cancer types, especially prostate, lung and colorectal cancers [ 10 ]. For instance, selenium levels below 60 μg/L have been associated with a higher risk of developing lung or laryngeal cancer [ 11 ]. Although recent studies in a variety of model systems have increased our understanding of the mechanisms of Se compounds in humans, efforts must still be made to develop formulation approaches for the oral administration of Se.…”