High dose of radioactive iodine per se has no effect on glucose metabolism in thyroidectomized rats.
Endocrine
; 56(2): 399-407, 2017 May.
Article
em En
| MEDLINE
| ID: mdl-28283939
ABSTRACT
PURPOSE:
Thyroid concentrates radioactive iodine by sodium-iodide symporter; this is used for treating hyperthyroidism and thyroid cancer. Pancreas expresses NIS and radioactive iodine uptake may damage pancreatic beta-cells and predispose patients to type 2 diabetes. The aim of this study was to determine whether radioactive iodine is associated with glucose metabolism in thyroidectomized rats.METHODS:
Forty male Wistar rats were divided into four groups (n = 10/each); control, thyroidectomized, thyroidectomized-treated with 131-I (TX+I), and thyroidectomized-treated with 131-I and L-thyroxine (TX+I+T4). At the end of study, serum fasting glucose, insulin, thyroid-stimulating hormone, and free tetraiodothyronine were measured, intraperitoneal glucose tolerance test was performed, and homeostasis model assessment-insulin resistance was calculated. In in vitro experiments, glucose-stimulated insulin secretion from pancreatic islets and sodium-iodide symporter mRNA expression in thyroid and islets were determined.RESULTS:
Compared to control group, free tetraiodothyronine was lower by 41 and 77% and thyroid-stimulating hormone was higher by 36 and 126% in thyroidectomized and TX+I groups, respectively. Compared to controls, rats in TX+I group had glucose intolerance as assessed using the area under curve of intraperitoneal glucose tolerance test (12,376 ± 542 vs. 20,769 ± 1070, P < 0.001) and L-thyroxine replacement therapy restored the value (14,286 ± 328.24) to near normal. Fasting insulin and homeostasis model assessment-insulin resistance were comparable in all groups, however fasting glucose was higher in TX+I group. In in vitro experiments, glucose-stimulated insulin secretion from islets did not differ between groups.CONCLUSION:
Radioactive iodine therapy per se had no effect on glucose metabolism, just intensified thyroid hormone deficiency and the alterations on glucose metabolism in thyroidectomized rats. L-thyroxine therapy restored the glucose intolerance observed in radioactive iodine-treated thyroidectomized rats.Palavras-chave
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Tiroxina
/
Glicemia
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Resistência à Insulina
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Tireotropina
/
Radioisótopos do Iodo
Idioma:
En
Ano de publicação:
2017
Tipo de documento:
Article