Efecto diferencial del síndrome metabólico sobre el metabolismo energético y composición de fibras en los músculos EDL y sóleo de ratas alimentadas con sacarosa en respuesta al ejercicio.

Rodríguez Correa, Eduardo; Carvajal Aguilera, Karla

BACKGROUND: Metabolic syndrome (MetS) severely affects population including children, predisposing them to the development of chronic diseases at early age, such as type II diabetes and cardiovascular diseases. Skeletal muscle acts as regulator of glucose and energy production and is affected during MetS. AIMS: To assess the molecular mechanisms associated to improvement of MetS during exercise, metabolic and gene expression remodeling that may be involved. METHODS: MetS was induced in 250 g male Wistar rats by 30% sucrose in drinking water. Animals receiving tap water were controls, both groups received solid standard diet. After 14 weeks, an endurance exercised group, and a sedentary one were formed in control and MetS animals. After eight weeks of training, the soleus and Extensor digitorum longus (EDL) muscles were dissected to asses contractile performance in an isolated organ device. Gene expression of myosin heavy chain (MyHC) isoforms, PGC1a, AMPKa2, NFATC1, MEF2a, SIX1, EYA1, FOXO1 and key metabolic enzymes activities were evaluated. RESULTS AND DISCUSSION: Exercise mildly improved MetS biochemical markers. MetS altered the contractile performance of the muscles, along with a mild-shift to a slow MyHC profile in EDL. FOXO1 increased in Soleus from MetS, whereas MEF2a and NFATC1 augmented under exercise, however PGC1a and SIX1 were unchange. NFATC1 decreased in EDL from MetS. Altered oxidative and glycolytic enzyme activities in MetS were partially reverted by exercise on the EDL. Soleus oxidative enzymes were enhanced by exercise on MetS as control. CONCLUSION: These results showed that MetS mostly affects EDL, exercise only partially reverts this. Soleus seems more resilient to MetS although it modifies the metabolic remodeling induced by exercise in EDL. We highlight the importance of studying both muscles during MetS, and their metabolic remodeling on the development of new therapies for MetS by exercise.

Acta Pediatrica de Mexico, 2024, Vol 45, Issue 2, pS16

0186-2391

Academic Journal