Endocrine Abstracts

Iodine (I) and selenium (Se) are two essential trace elements for regular thyroid gland functioning and thyroid hormone metabolism. Most Europeans are only marginally supplied with both elements through their daily nutrition. The mammalian organism has developed efficient and highly complex mechanisms to control I and Se uptake, metabolism and recycling. The thyroid gland is equipped with the necessary transporters and metabolizing enzymes for I uptake and bioconversion into t...

Selenium (Se) is an essential trace element and is important for maintaining health and preventing disease. Se exhibits its biological function as the 21st proteinogenic amino acid selenocysteine (Sec). Different cis and trans acting factors are necessary for incorporation of Sec into proteins. Se can be transported and stored as Sec in selenoprotein P (SePP), a liver-derived protein which contains up to 10 Sec residues per protein in humans. Thus, SePP functions...

Many endocrine disorders bear an immunological component and involve local cytokines as paracrine signals. Moreover, certain auto-antibodies appear as causative pathological agents in some of the most common endocrine diseases e.g. in type I diabetes mellitus or different forms of autoimmune thyroid disease (AITD). Recently, selenium (Se) status and selenoproteins have emerged as important modifiers of the inflammatory response, AITD or sepsis. Notably, mortality risk of patie...

Background: Selenoproteins contain the 21st proteinogenic amino acid selenocysteine (Sec) and exert important biological functions. Selenoprotein S (SelS) has only recently been identified and appears to be implicated in type 2 diabetes and inflammation. In vitro studies have shown that SelS expression is controlled by circulating cytokine and glucose levels. Mechanistically, SelS participates in the retro-translocation during quality control in the ER and the ER-associ...

Background: Selenoproteins are involved in oxidative stress defence, cell signalling and hormone metabolism. Accordingly, impairment of selenium (Se) metabolism or transport results in a complex phenotype as exemplified in selenoprotein P knockout mice (SePP-KO). This mouse model is characterized by a disrupted metabolism of Se resulting in neurological and growth defects. Hypothesis: Se impairs regular tissue development by modifying growth signal biosynthesis, anabolic respo...

Background: Selenoproteins are playing an important role in body homeostasis and development. They control thyroid hormone metabolism and are of prime importance for intracellular redox regulation and cellular defence. The SePP knockout mouse (SePP-KO) is a model of impaired Se metabolism characterized by a disrupted distribution system for organified Se. One of the major phenotypes of the homozygote SePP-KO mice is a reduced increase in size and weight during the growth spurt...

Objectives: Deiodinase type 1 (DIO1), a selenocysteine-containing enzyme belonging to the deiodinase (DIO) family, plays an essential role in the systemic and local modulation of thyroid hormone (TH) availability. However, DIO1 plays a dual role by not only converting the prohormone thyroxine (T4) to the active triiodothyronine (T3) but also degrading T3 to the inactive 3,3’-diiodothyronine (3,3’-T2). DIO1, by acting on sulfated TH metabolites, further contributes to...

BackgroundDevelopment and application of novel drugs frequently fail due to adverse changes of TH-levels or thyroid histology in animal experiments. Such effects potentially arise from interference with thyroid gland function or key regulators of local thyroid hormone (TH) transport, metabolism and action. Deiodinases are key enzymes in TH in-/activation, with impact on development, cell differentiation and energy metabolism among other physiological pro...

Thyroid hormone (TH) homeostasis depends on the coordination of several key events to maintain proper local TH signaling, including iodide uptake, hormone synthesis, metabolism, and elimination. The three isoenzymes, Deiodinases (DIO1-3), are essential components of hormone metabolism. They catalyze iodide release the outer and/or inner ring of TH structure to convert between their active and inactive forms. The activity of DIOs has been identified as an important endpoint reg...