TGF-beta2 prevents the impaired chondrocyte proliferation induced by unloading in growth plates of young rats.
Life Sci
; 61(24): 2397-406, 1997.
Article
en En
| MEDLINE
| ID: mdl-9399632
ABSTRACT
Growth plate width and cartilage organization are altered during skeletal unloading in growing rats. Immunohistochemical studies have identified TGF-beta in calcified cartilage, and TGF-beta is known to induce mitogenic effects on chondrocytes in vitro. On the other hand, IGF-1 was shown to be expressed in the proximal tibial growth plate and to mediate GH-induced longitudinal bone growth in rats. We therefore investigated the effect of recombinant human (rh) IGF-1 and rhTGF-beta2 infusion on the changes induced by unloading in the cellular organization of the growth plate in growing rats. Hindlimb unloading for 14 days induced a 13% reduction in growth cartilage height in the proximal tibia. This effect was mostly related to a 17% and 14% decrease in the proliferative zone height and chondrocyte number, respectively. In unloaded rats treated with a systemic infusion of rhTGF-beta2 (2microg/kg/day) the number of chondrocytes in the proliferative zone was not different from those of normal loaded animals. In contrast, rhIGF-1 treatment at a 2mg/kg/day dose was not effective in counteracting the effects of unloading on growth plate height and chondrocyte number. These results show that systemic administration of rhTGF-beta2 prevents in large part the reduced growth of chondrocytes in the proliferative zone and the reduced epiphyseal growth plate growth induced by unloading in rats.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Factor de Crecimiento Transformador beta
/
Condrocitos
/
Placa de Crecimiento
Tipo de estudio:
Prognostic_studies
Límite:
Animals
/
Humans
/
Male
Idioma:
En
Revista:
Life Sci
Año:
1997
Tipo del documento:
Article
País de afiliación:
Francia