Anti-oxidant effect of metformin through AMPK/SIRT1/PGC-1 alpha/SIRT3- independent GPx1 expression in the heart of mice with endometriosis

Autores da FMUP

• Alexandra Maria Monteiro Gouveia

  Autor

• Henrique Manuel Nunes De Almeida

  Autor

• Delminda Rosa Gamelas Neves Lopes De Magalhães

  Autor

Participantes de fora da FMUP

• Felgueiras, R
• Neto, AC
• Rodrigues, AR

Unidades de investigação

• Biomedicina

Abstract

Objectives: Endometriosis is a gynecological disease associated with an imbalance between oxidative species production and anti-oxidativedefenses. In women, endometriosis has been reported to associate with increased incidence of cardiovascular events. As such, this study aimed to analyze the oxidation-responsive AMPK/SIRT1/PGC-1 alpha/SIRT3 pathway in the heart of a mouse model of endometriosis. The effect of metformin, an insulin-sensitizing and anti-oxidative drug with already shown positive results in endometriotic tissue was studied. Methods: Thirty-six female B6CBA/F1 mice were divided into 4 groups (Control-C, Surgery-induced Endometriosis and Metformin-EM (50 mg/kg/day orally administrated for 3 months), Endometriosis-E and Metformin-M). Immunofluorescent labelling of SIRT1 and SIRT3 was performed in the heart tissue. Assessment of expression of AMPK alpha, SIRT1, PGC-1 alpha, SIRT3, SOD2, and GPx1 was performed by Western Blotting. The quantification of microRNA(miR)-34a, miR-195, miR-217, miR-155 and miR-421, involved in the regulation of expression of SIRT1 and SIRT3, was performed by Real-Time PCR. Results: Data showed an increase in phospho-AMPK alpha and in GPx1 expression in the EM group when compared to the C group, but not in the total AMPK, SIRT1, PGC-1 alpha, SIRT3 and SOD2, suggesting a GPx1 expression increase independently of the AMPK/SIRT1/PGC-1 alpha/SIRT3 pathway. MicroRNAs, excepting miR-217, showed a consistent trend of increase in the M group. Conclusions: Our study showed that endometriosis does not significantly affect the expression of the components of the AMPK/SIRT1/PGC-1 alpha/SIRT3 pathway in the heart. However, it indicates that an oxidative condition underlying endometriosis is required formetformin to evidence an increment in the expression of the anti-oxidative enzyme GPx1.

Keywords

• AMPK; cardiovascular disease; endometriosis; glutathione peroxidase 1; metformin