Interaction between Overtraining and the Interindividual Variability May (Not) Trigger Muscle Oxidative Stress and Cardiomyocyte Apoptosis in Rats

Autor(es)

Perroni Ferraresso, Rodrigo Luiz ; de Oliveira, Renato Buscariolli ; Macedo, Denise Vaz ; Soares Nunes, Lazaro Alessandro ; Brenzikofer, Rene ; Damas, Danilo ; Hohl, Rodrigo

• Tipo de documento: Artigo Científico
• Fonte: OXIDATIVE MEDICINE AND CELLULAR LONGEVITY; v. 2012, p. 11-pg., 2012-01-01.

Resumo

Severe endurance training (overtraining) may cause underperformance related to muscle oxidative stress and cardiomyocyte alterations. Currently, such relationship has not been empirically established. In this study, Wistar rats (n = 19) underwent eight weeks of daily exercise sessions followed by three overtraining weeks in which the daily frequency of exercise sessions increased. After the 11th training week, eight rats exhibited a reduction of 38% in performance (nonfunctional overreaching group (NFOR)), whereas eleven rats exhibited an increase of 18% in performance (functional overreaching group (FOR)). The red gastrocnemius of NFOR presented significantly lower citrate synthase activity compared to FOR, but similar to that of the control. The activity of mitochondrial complex IV in NFOR was lower than that of the control and FOR. This impaired mitochondrial adaptation in NFOR was associated with increased antioxidant enzyme activities and increased lipid peroxidation (in muscle and plasma) relative to FOR and control. Cardiomyocyte apoptosis was higher in NFOR. Plasma creatine kinase levels were unchanged. We observed that some rats that presented evidence of muscle oxidative stress are also subject to cardiomyocyte apoptosis under endurance overtraining. Blood lipid peroxides may be a suitable biomarker for muscle oxidative stress that is unrelated to severe muscle damage. (AU)

• Processo FAPESP: 07/57511-6 - Acompanhamento de parametros cardiovasculares ao longo de um protocolo de inducao ao overtraining em ratos wistar.
• Beneficiário: Renato Buscariolli de Oliveira
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 09/51125-2 - Aplicação de um modelo animal de indução ao overtraining para consolidação de linha de apesquisa e estabelecimento de valores de referência da razão glutamina/glutamato par prevenção do overreaching não funcional
• Beneficiário: Rodrigo Hohl
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 07/57512-2 - Estudo da relacao entre ataque oxidativo, sistema de defesa antioxidante e atividade mitocondrial em ratos submetidos a um protocolo de inducao ao overtraining em esteira.
• Beneficiário: Rodrigo Luiz Perroni Ferraresso
• Modalidade de apoio: Bolsas no Brasil - Mestrado