title: Thyroid hormone treatment decreases hepatic glucose production and renal reabsorption of glucose in alloxan-induced diabetic Wistar rats.
abstract: The thyroid hormone (TH) plays an important role in glucose metabolism. Recently, we showed that the TH improves glycemia control by decreasing cytokines expression in the adipose tissue and skeletal muscle of alloxan-induced diabetic rats, which were also shown to present primary hypothyroidism. In this context, this study aims to investigate whether the chronic treatment of diabetic rats with T3 could affect other tissues that are involved in the control of glucose homeostasis, as the liver and kidney. Adult Male Wistar rats were divided into nondiabetic, diabetic, and diabetic treated with T3 (1.5 μg/100 g BW for 4 weeks). Diabetes was induced by alloxan monohydrate (150 mg/kg, BW, i.p.). Animals showing fasting blood glucose levels greater than 250 mg/dL were selected for the study. After treatment, we measured the blood glucose, serum T3, T4, TSH, and insulin concentration, hepatic glucose production by liver perfusion, liver PEPCK, GAPDH, and pAKT expression, as well as urine glucose concentration and renal expression of SGLT2 and GLUT2. T3 reduced blood glucose, hepatic glucose production, liver PEPCK, GAPDH, and pAKT content and the renal expression of SGLT2 and increased glycosuria. Results suggest that the decreased hepatic glucose output and increased glucose excretion induced by T3 treatment are important mechanisms that contribute to reduce serum concentration of glucose, accounting for the improvement of glucose homeostasis control in diabetic rats.
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Silvania da Silva
authors.initials: SD
authors.lastname: Teixeira
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Ana C
authors.initials: AC
authors.lastname: Panveloski-Costa
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Aline
authors.initials: A
authors.lastname: Carvalho
authors.affiliation: Department of Pharmacology and Therapeutics, State University of Maringa, Maringa, Parana, Brazil.
authors.forename: Fabiana P
authors.initials: FP
authors.lastname: Monteiro Schiavon
authors.affiliation: Department of Pharmacology and Therapeutics, State University of Maringa, Maringa, Parana, Brazil.
authors.forename: Any de Castro
authors.initials: AC
authors.lastname: Ruiz Marque
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Raquel S
authors.initials: RS
authors.lastname: Campello
authors.affiliation: Department of Pharmacology and Therapeutics, State University of Maringa, Maringa, Parana, Brazil.
authors.forename: Roberto B
authors.initials: RB
authors.lastname: Bazotte
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil mtnunes@icb.usp.br.
authors.forename: Maria T
authors.initials: MT
authors.lastname: Nunes
keywords: Diabetes Mellitus; SGLT2; gluconeogenesis; liver perfusion; thyroid hormone