Autophagy in mineralizing tissues: microenvironmental perspectives.
Cell Cycle
; 8(3): 391-3, 2009 Feb 01.
Article
en En
| MEDLINE
| ID: mdl-19177014
Chondrocytes in the growth plate and articular cartilage and osteocytes subsumed in Haversian bone exist in environmental niches that are characterized by a limited oxygen supply. In these tissues, cells display a hitherto unrecognized state in which there is evidence of autophagy. The autophagic condition serves to promote cell survival. When the response is triggered, the cell cannibalizes itself to generate energy; if extended, then it can activate Type II apoptosis. We opine that survival is dependent on niche conditions and regulated by crosstalk between mTOR, AMPK and HIF-1 and HIF-2. Recent studies suggest that HIF-2 is a potent regulator of chondrocyte autophagy and that this protein acts as a brake to the stimulatory function of HIF-1. Accordingly, the oxemic state of the tissue, its nutrient supply as well as the energetic state of the cells regulates autophagic flux. From a clinical viewpoint, it may be possible to enhance skeletal cell survival through drugs that modulate the autophagic state and prevent the induction of apoptosis.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Autofagia
/
Calcificación Fisiológica
/
Condrocitos
/
Ambiente
Idioma:
En
Revista:
Cell Cycle
Año:
2009
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Estados Unidos