Intestine of dystrophic mice presents enhanced contractile resistance to stretching despite morphological impairment

Autor(es)

Alves, Gabriel A. ^[1] ; Silva, Luisa R. ^[1] ; Rosa, Eloi F. ^[1] ; Aboulafia, Jeannine ^[1] ; Freymueller-Haapalainen, Edna ^[2] ; Souccar, Caden ^[3] ; Nouailhetas, Viviane L. A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo, Escola Paulista Med, Dept Biophys, BR-04023062 Sao Paulo - Brazil

^[2] Univ Fed Sao Paulo, Escola Paulista Med, Ctr Microscopia Eletron, BR-04023062 Sao Paulo - Brazil

^[3] Univ Fed Sao Paulo, Escola Paulista Med, Dept Pharmacol, BR-04023062 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY; v. 306, n. 3, p. G191-G199, FEB 2014.
• Citações Web of Science: 4

Resumo

Protein dystrophin is a component of the dystrophin-associated protein complex, which links the contractile machinery to the plasma membrane and to the extra-cellular matrix. Its absence leads to a condition known as Duchenne muscular dystrophy (DMD), a disease characterized by progressive skeletal muscle degeneration, motor disability, and early death. In mdx mice, the most common DMD animal model, loss of muscle cells is observed, but the overall disease alterations are less intense than in DMD patients. Alterations in gastrointestinal tissues from DMD patients and mdx mice are not yet completely understood. Thus, we investigated the possible relationships between morphological (light and electron microscopy) and contractile function (by recording the isometric contractile response) with alterations in Ca2+ handling in the ileum of mdx mice. We evidenced a 27% reduction in the ileal muscular layer thickness, a partial damage to the mucosal layer, and a partial damage to mitochondria of the intestinal myocytes. Functionally, the ileum from mdx presented an enhanced responsiveness during stretch, a mild impairment in both the electromechanical and pharmacomechanical signaling associated with altered calcium influxinduced contraction, with no alterations in the sarcoplasmic reticulum Ca2+ storage (maintenance of the caffeine and thapsigargin-induced contraction) compared with control animals. Thus, it is evidenced that the protein dystrophin plays an important role in the preservation of both the microstructure and ultrastructure of mice intestine, while exerting a minor but important role concerning the intestinal contractile responsiveness and calcium handling. (AU)

• Processo FAPESP: 07/58132-9 - Analise morfofuncional do ileo de camundongos submetidos a fatores estressantes da musculatura esqueletica: exercicio fisico e distrofia muscular de duchenne.
• Beneficiário: Viviane Louise Andree Nouailhetas
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/15716-9 - Avaliação morfofuncional e estresse oxidativo no intestino de camundongos distróficos (mdx)
• Beneficiário: Viviane Louise Andree Nouailhetas
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 07/59976-6 - Avaliação morfofuncional e estresse oxidativo no intestino de camundongos distróficos
• Beneficiário: Gabriel Andrade Alves
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto