Effects of exercise intensity on soleus muscle myostatin and follistatin levels of hyperglycaemic rats (Efectos de la intensidad del ejercicio sobre la miostatina y folistatina del músculo sóleo de ratas hiperglicémicas)

Abstract


 Background: Hyperglycaemia induces dysregulations in skeletal muscle mass and function. Myostatin (Mstn) and follistatin (Fs) are two key regulators of muscle mass, which are known to be dysregulated in people with hyperglycaemia. Exercise is frequently prescribed to counteract these changes; however, the influence of exercise intensity is unknown. The purpose of this study was to compare two training programs, moderate-intensity constant (MICT) and high-intensity interval training (HIIT), on soleus mRNA levels of Mstn and Fs in an animal model of hyperglycaemia. Material and Methods: 36 male Wistar rats, were divided into control (n=18) and hyperglycaemic (HG, n=18; induced by a single intraperitoneal dose of Streptozotocin) groups. Subsequently, these groups were randomly subdivided into control untrained, control+moderate-intensity constant training (MICT), control+high-intensity interval training (HIIT), HG untrained, HG+MICT, and HG+HIIT (n=6 each subgroup). Training programs were performed for 8 weeks, with a frequency of 5 sessions per week. The total distance covered per session in MICT and HIIT was equal. 48 hours following the last training session, rats were anesthetized and soleus muscles were excised. Results: HIIT reduced and increased significantly the Mstn and Fs mRNA levels respectively, irrespective of hyperglycaemia (p<0.05). When Mstn:Fs ratio was analysed, only HIIT induced a significant increase in hyperglycaemic rats (p<0.05). Conclusion: HIIT over MICT, changed the Mstn and Fs soleus mRNA levels, irrespective of hyperglycaemia. This could indicate that the regulation of these genes is exercise intensity-dependent, whereas hyperglycaemia seems to not blunt this response. 
 Resumen. Antecedentes: La hiperglicemia induce alteraciones en la masa y fuerza del músculo esquelético. La miostatina (Mstn) y folistatina (Fs) son reguladores de masa muscular, los cuales son alterados por hiperglicemia. El ejercicio es utilizado para neutralizar estos cambios; sin embargo, la influencia de la intensidad del mismo no está aclarada. Este estudio comparó dos programas de ejercicio, intensidad moderada y constante (MICT) e interválico de alta intensidad (HIIT), sobre los niveles de ARN mensajero (ARNm) muscular de Mstn y Fs en ratas hiperglicémicas. Material y Métodos: 36 ratas Wistar fueron divididas en controles (n=18) y con hiperglicemia (HG, n=18; inducida con Streptozotocina intraperitoneal). Además, estos grupos fueron subdivididos aleatoriamente en: control no-entrenado, control+entrenamiento moderado constante (MICT), control+entrenamiento interválico de alta intensidad (HIIT), HG no-entrados, HG+MICT y HG+HIIT (cada subgrupo n=6). El entrenamiento duró 8 semanas, con 5 sesiones por semana. La distancia total recorrida por sesión en cada programa de entrenamiento fue igual. 48 horas posterior a la última sesión, las ratas fueron anestesiadas y los músculos sóleos fueron extraídos. Resultados: El entrenamiento HIIT redujo e incrementó significativamente los niveles de Mstn y Fs respectivamente, independiente de la presencia de hiperglicemia (p<0.05). Además, la razón Mstn:Fs se incrementó significativamente sólo en el grupo de ratas hiperglicémicas entrenadas con HIIT (p<0.05). Conclusión: El entrenamiento HIIT, no MICT, cambió los niveles de ARNm de Mstn y Fs en el músculo sóleo, independiente de la presencia de hiperglicemia. Esto sugiere que la regulación de estos genes es dependiente de la intensidad del ejercicio, en donde la hiperglicemia parece no aminorar esta respuesta.

Acute effects of moderate-intensity constant training on circulatory fibroblast growth factor 21, resis-tin, and adiponectin of physically inactive young adults

“…Therefore, the aim of this study was to investigate the effects of one session of moderate-intensity continuous (MICT) training on the circulatory levels of FGF-21, resistin and adiponectin in physically inactive young adults. We selected MICT as exercise program given its previously described benefits in different contexts of health and disease (Collados-Gutiérrez & Gutiérrez Vilahú, 2023;Farhani et al, 2022;Sari et al, 2023).…”