Cardioprotective doses of thyroid hormones improve NO bioavailability in erythrocytes and increase HIF-1α expression in the heart of infarcted rats

Abstract

Context

Infarction leads to a decrease in NO bioavailability in the erythrocytes. Thyroid hormones (TH) present positive effects after infarction. However, there are no studies evaluating the effects of cardioprotective doses of TH in the erythrocytes after infarction.

Objective

This study aimed to evaluate the effects of TH in NO bioavailability and oxidative stress parameters in the erythrocytes of infarcted rats.

Material and methods

Wistar rats were allocated into the three groups: Sham-operated (SHAM), infarcted (AMI) and infarcted + TH (AMIT). AMIT rats received T4 and T3 for 12 days by gavage. Subsequently, the animals were evaluated by echocardiography and the LV and erythrocytes were collected.

Results

TH improved NO bioavailability and increased catalase activity in the erythrocytes. Besides that, TH increased HIF-1α in the heart.

Conclusion

TH seems to be positive for erythrocytes preventing a decrease in NO bioavailability and increasing antioxidant enzymatic defense after infarction.

Keywords:

• T3
• T4
• nitric oxide
• reactive oxygen species
• oxidative stress

Acknowledgements

This work was supported by the Brazilian Research Agencies: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenacão de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Fundação de Amparo à Pesquisa do Rio Grande do Sul (FAPERGS).

Disclosure statement

No potential conflict of interest was reported by the author(s).