Efeito do exercício sobre a espessura da parede do coração e sobre a fibrose do músculo cardíaco em camundongos com distrofia muscular

USA - camundongos com distrofia muscular, com 11 semanas de vida, foram submetidos a exercícios físicos; os camundongos sedentários apresentaram maior espessura do músculo cardíaco e menor fibrose do que os camundongos que foram submetidos a exercícios físicos.

O resumo em inglês pode ser lido abaixo:

(FASEB Meeting, 2010) The Effects of Exercise on Ventricular Wall Thickness and Fibrosis in Wild-Type and Dystrophin-Deficient Mice

Jeffrey H Plochocki and Jeffrey M Costas

Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ

Dystrophin is a cytoplasmic protein that connects muscle cells to the extracellular matrix. When absent, muscle degeneration and fibrosis occurs that resembles the histopathological presentation of Duchenne muscular dystrophy. In mice that lack dystrophin (Mdx mice), there is muscle degeneration and regeneration in the first few months of life, with fibrosis increasing after that. In this study, we evaluated the relationship between exercise and lateral ventricular wall thickness (LVT) in wild-type and Mdx mice aged 11 weeks. Degree of cardiac fibrosis was assessed using a trichrome stain. Sedentary Mdx mice exhibited significantly larger LVT than wild-type mice (P < 0.05). Exercise treated wild-type mice had larger LVT than sedentary wild-type mice on average, but this difference was not statistically significant. The LVT of sedentary Mdx mice was 28% larger than that of exercise treated Mdx mice (P < 0.05). Exercised treated Mdx mice were the only group that exhibited any noticeable fibrosis in the lateral aspect of the heart. Our findings suggest that exercise within the normal physiological range can accelerate degeneration and fibrosis of the lateral ventricular wall in Mdx mice.

Fonte: http://distrofiamuscular.net/noticias.htm