Cancer- and endotoxin-induced cachexia require intact glucocorticoid signaling in skeletal muscle.
FASEB J
; 27(9): 3572-82, 2013 Sep.
Article
em En
| MEDLINE
| ID: mdl-23733748
ABSTRACT
Cachexia is a wasting condition defined by skeletal muscle atrophy in the setting of systemic inflammation. To explore the site at which inflammatory mediators act to produce atrophy in vivo, we utilized mice with a conditional deletion of the inflammatory adaptor protein myeloid differentiation factor 88 (MyD88). Although whole-body MyD88-knockout (wbMyD88KO) mice resist skeletal muscle atrophy in response to LPS, muscle-specific deletion of MyD88 is not protective. Furthermore, selective reexpression of MyD88 in the muscle of wbMyD88KO mice via electroporation fails to restore atrophy gene induction by LPS. To evaluate the role of glucocorticoids as the inflammation-induced mediator of atrophy in vivo, we generated mice with targeted deletion of the glucocorticoid receptor in muscle (mGRKO mice). Muscle-specific deletion of the glucocorticoid receptor affords a 71% protection against LPS-induced atrophy compared to control animals. Furthermore, mGRKO mice exhibit 77% less skeletal muscle atrophy than control animals in response to tumor growth. These data demonstrate that glucocorticoids are a major determinant of inflammation-induced atrophy in vivo and play a critical role in the pathogenesis of endotoxemic and cancer cachexia.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Caquexia
/
Atrofia Muscular
/
Músculo Esquelético
/
Carcinoma Pulmonar de Lewis
/
Fator 88 de Diferenciação Mieloide
/
Glucocorticoides
Limite:
Animals
Idioma:
En
Revista:
FASEB J
Assunto da revista:
BIOLOGIA
/
FISIOLOGIA
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Estados Unidos