Thyroxine increases Serca2 and Ryr2 gene expression in heart failure rats with euthyroid sick syndrome

• Autor(a) principal: Campanha, Fábio V.G. [UNESP]
• Data de Publicação: 2016
• Outros Autores: Perone, Denise [UNESP], de Campos, Dijon H.S. [UNESP], de Luvizotto, Renata A. M., de Síbio, Maria T. [UNESP], de Oliveira, Miriane [UNESP], Olimpio, Regiane M. C. [UNESP], Moretto, Fernanda C. F. [UNESP], Padovani, Carlos R. [UNESP], Mazeto, Gláucia M.F.S. [UNESP], Cicogna, Antonio C. [UNESP], Nogueira, Célia R. [UNESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1590/2359-3997000000208; http://hdl.handle.net/11449/173914
• topic: Calcium channels; Heart failure; Reverse triiodothyronine; Therapeutic use; Triiodothyronine

Objective: The current study was aimed at analyzing sarcoplasmic reticulum Ca2+ ATPase (Serca2) and ryanodine receptor type 2 (Ryr2) gene expression in rats subjected to surgery that induced HF and were subsequently treated with T4 using physiological doses. Materials and methods: HF was induced in 18 male Wistar rats by clipping the ascending thoracic aorta to generate aortic stenosis (HFS group), while the control group (9-sham) underwent thoracotomy. After 21 weeks, the HFS group was subdivided into two subgroups. One group (9 Wistar rats) with HF received 1.0 µg of T4/100 g of body weight for five consecutive days (HFS/T4); the other group (9 Wistar rats) received isotonic saline solution (HFS/S). The animals were sacrificed after this treatment and examined for signs of HF. Samples from the left ventricles of these animals were analyzed by RT-qPCR for the expression of Serca2 and Ryr2 genes. Results: Rats with HF developed euthyroid sick syndrome (ESS) and treatment with T4 restored the T3 values to the Sham level and increased Serca2 and Ryr2 gene expression, thereby demonstrating a possible benefit of T4 treatment for heart function in ESS associated with HF. Conclusion: The T4 treatment can potentially normalize the levels of T3 as well elevated Serca2 and Ryr2 gene expression in the myocardium in heart failure rats with euthyroid sick syndrome.