Excess iodide induces an acute inhibition of the sodium/iodide symporter in thyroid male rat cells by increasing reactive oxygen species

Alejandro A. Arriagada, Eduardo Albornoz, Ma Cecilia Opazo, Alvaro Becerra, Gonzalo Vidal, Carlos Fardella, Luis Michea, Nancy Carrasco, Felipe Simon, Alvaro A. Elorza, Susan M. Bueno, Alexis M. Kalergis, Claudia A. Riedel

Research output: Contribution to journalArticlepeer-review

19 Citations (Scopus)

Abstract

Na+/I- symporter (NIS) mediates iodide (I-) uptake in the thyroid gland, the first and rate-limiting step in the biosynthesis of the thyroid hormones. The expression and function of NIS in thyroid cells is mainly regulated by TSH and by the intracellular concentration of I-. High doses of I- for 1 or 2 days inhibit the synthesis of thyroid hormones, a process known as the Wolff-Chaikoff effect. The cellular mechanisms responsible for this physiological response are mediated in part by the inhibition of I- uptake through a reduction of NIS expression. Here we show that inhibition of I- uptake occurs as early as 2 hours or 5 hours after exposure to excess I- in FRTL-5 cells and the rat thyroid gland, respectively. Inhibition of I- uptake was not due to reduced NIS expression or altered localization in thyroid cells. We observed that incubation of FRTL-5 cells with excess I- for 2 hours increased H2O2 generation. Furthermore, the inhibitory effect of excess I- on NIS-mediated I- transport could be recapitulated by H2O2 and reverted by reactive derived oxygen species scavengers. The data shown here support the notion that excess I- inhibits NIS at the cell surface at early times by means of a posttranslational mechanism that involves reactive derived oxygen species.

Original languageEnglish
Pages (from-to)1540-1551
Number of pages12
JournalEndocrinology
Volume156
Issue number4
DOIs
Publication statusPublished - 1 Apr 2015

ASJC Scopus subject areas

  • Endocrinology

Fingerprint

Dive into the research topics of 'Excess iodide induces an acute inhibition of the sodium/iodide symporter in thyroid male rat cells by increasing reactive oxygen species'. Together they form a unique fingerprint.

Cite this