Skeletal muscle atrophy increases cell proliferation in mice gastrocnemius during the first week of hindlimb suspension

• Tipo: Artigo em Revista Científica Internacional
• Data: 2006

Autores

ferreira, r (Autor) Outra; neuparth, mj (Autor) Outra; ascensao, a (Autor) FADEUP; magalhaes, j (Autor) FADEUP; vitorino, r (Autor) Outra; duarte, ja (Autor) FADEUP; amado, f (Autor) Outra

Revista

Título: European Journal of Applied Physiology

Vol. 97 Nº 3

Páginas: 340-346

ISSN: 1439-6319

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 32 Citações

Scopus - 32 Citações

Pubmed / Medline

Classificação Científica

FOS: Ciências médicas e da saúde > Medicina básica

Outras Informações

ID Authenticus: P-004-KCR

DOI: 10.1007/s00421-006-0197-6

Abstract (EN): The comprehension of the cellular mechanisms underlying skeletal muscle atrophy has been the aim of several experimental studies. However, the majority of them focused on alterations of the myocytes induced by different experimental conditions yet disregarding the contribution of other cells such as endothelial cells and fibroblasts. In this sense, 70 Charles River CD1 male mice were randomly assigned to seven groups (n = 10 per group): control and 6, 12, 24, 48, 72 h and 1 week with respect to the period of hindlimb suspension. Forty-eight hours before sacrifice, the animals were injected with bromodeoxyuridine (BrdU) in order to identify proliferating cells. Immunohistochemistry and south-western blotting techniques were used to evaluate across the whole gastrocnemius muscle BrdU incorporation into the different proliferating cells. The contribution of the apoptotic response was also measured in order to ascertain whether the balance between cell survival and death was preserved. The results observed during 1 week of unloading-induced atrophy evidenced an intense peak of proliferating activity only after 6 h, mainly due to the duplication of satellite cells. Consequently to this unexpected activation of satellite cells, the addition of nuclei to the fibre syncytium was recognized at 12 h of unloading. After 48 h of weightlessness, the proliferating activity observed was largely due to an interstitial fibrosis. According to the apoptotic index profile observed during the analysed unloading period, this general proliferative activity was balanced by apoptosis, which strongly suggests the existence of a regulatory feedback response between anabolic and catabolic events in unloading-induced skeletal muscle atrophy.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7