Effects of repeated potassium iodide administration on genes involved in synthesis and secretion of thyroid hormone in adult male rat

Dalila Lebsir (1) , Line Manens (1) , Stephane Grison (1) , Philippe Lestaevel (2) , Teni Ebrahimian Chiusa (1) , David Suhard (3) , Guillaume Phan (3) , Isabelle Dublineau (4) , Karine Tack (1) , Marc Benderitter (5) , Annick Pech (6) , Jean Rene Jourdain (7) , Maamar Souidi (8)

1 IRSN/PSE-SANTE/SESANE/LRTOX - Laboratoire de radiotoxicologie et radiobiologie expérimentale
2 IRSN/PSE-SANTE/SER/BASEP - Bureau d'analyse et de suivi des expositions professionnelles
3 IRSN/PSE-SANTE/SESANE/LRSI - Laboratoire de recherche en Radiochimie, Spéciation et Imagerie
4 IRSN/PSE-ENV/SEDRE/USDR - Unité d'expertise des sites et des déchets radioactifs
5 IRSN/PSE-SANTE/SERAMED/LRMed - Laboratoire de Radiobiologie des expositions médicales
6 Pharmacie centrale des armées, Direction des Approvisionnement en produits de Santé des Armées
7 IRSN/DAEI - Direction des Affaires Européennes et Internationales
8 IRSN/PSE-SANTE/SERAMED/LRAcc - Laboratoire de Radiobiologie des expositions accidentelles

Background A single dose of potassium iodide (KI) is recommended to reduce the risk of thyroid cancer during nuclear accidents. However in case of prolonged radioiodine exposure, more than one dose of KI may be necessary. This work aims to evaluate the potential toxic effect of repeated administration of KI. Methods Adult Wistar rats received an optimal dose of KI 1 mg/kg over a period of 1, 4 or 8 days. Results hormonal status (TSH, FT4) of treated rats was unaffected. Contrariwise, a sequential Wolff-Chaikoff effect was observed, resulting in a prompt decrease of NIS and MCT8 mRNA expression (−58% and −26% respectively), followed by a delayed decrease of TPO mRNA expression (−33%) in conjunction with a stimulation of PDS mRNA expression (+62%). Conclusion we show for the first time that repeated administration of KI at 1 mg/kg/24h doesn't cause modification of thyroid hormones level, but leads to a reversible modification of the expression of genes involved in the synthesis and secretion of thyroid hormones.

Domaines: Sciences du Vivant [q-bio]

Dalila Lebsir, Line Manens, Stephane Grison, Philippe Lestaevel, Teni Ebrahimian Chiusa, et al.. Effects of repeated potassium iodide administration on genes involved in synthesis and secretion of thyroid hormone in adult male rat. Molecular and Cellular Endocrinology, 2018, 474, pp.119-126. ⟨10.1016/j.mce.2018.02.017⟩. ⟨hal-02457220⟩