Suplementação de antioxidante ácido ascórbico na dieta de camundongos MDX (um modelo de distrofia muscular de Duchenne): repercussões morfológicas no músculo liso (estrutura primária) e no plexo mioentérico (estrutura secundária) do íleo

Abstract

The Duchenne muscular dystrophy (DMD) is a hereditary disease where there is a lack of dystrophin protein, leading to severe injury myopathy frames resulting from increased oxidative stress and Ca + influx. Lesions on intestinal smooth muscle can compromise the local motility due to changes in the very muscular layer structure as well as the morphological and functional changes in the myenteric plexus structures. This study aimed to evaluate changes in the muscular wall and myenteric cholinergic neurons of the ileum of mdx mice, and the effects of supplementation with ascorbic acid (AA) in these two components. 30 male C57BL / 10 and 30 C57BL / 10Mdx separated into groups according to age and treatment (n = 10) were control at 30 days old (C30); dystrophic 30 days of age (D30); control with 60 days of age (C60); dystrophic with 60 days of age (D60); control at 60 days of age supplemented with ascorbic acid (200mg / kg body weight) (CS60) and dystrophic 60 days of age supplemented with ascorbic acid (200mg / kg body weight) (DS60). After the trial period the animals were euthanized and ileus have been collected and processed following the histological routine and stained by Masson's technique of Masson and for immunohistochemical technique of acetylcholinesterase in total membrane prepared. The data demonstrated that the thickness of the muscularis (μm) and smooth muscle area (μm 2) of the ileum was lower in dystrophic groups, especially Group D30. In animal DS60 the thickness of the muscular layer was similar to the C60. Decreased cholinergic neuronal density of the myenteric plexus of the ileum was lower in D30 animals, but this was similar in animals 60 days without treatment (C60 and D60) and higher in DS60 animals. Cell body profile area (μm 2) was similar in animals of C30-C60 and D30-D60, but is was higher in DS60. The nuclear area ratio / cytoplasmic area was lower in D30 and DS60 and higher in D60. Thus we conclude that mdx mice occur in significant changes in the morphology of the muscular layer and, consequently, morphological and functional changes of cholinergic neurons of the myenteric plexus of the ileum and that supplementation with AA had neuroprotective effects in these animals as preventing loss Neuronal.