IGFBP-2 directly stimulates osteoblast differentiation.

ABSTRACT: Insulin-like growth factor binding protein 2 (IGFBP-2) is important for acquisition of normal bone mass in mice; however, the mechanism by which IGFBP-2 functions is not defined. These studies investigated the role of IGFBP-2 in stimulating osteoblast differentiation. MC-3T3 preosteoblasts expressed IGFBP-2, and IGFBP-2 knockdown resulted in a substantial delay in osteoblast differentiation, reduced osteocalcin expression and Alizarin red staining. These findings were replicated in primary calvarial osteoblasts obtained from IGFBP-2(-/-) mice, and addition of IGFBP-2 rescued the differentiation program. In contrast, overexpression of IGFBP-2 accelerated the time course of differentiation as well as increasing the total number of differentiating cells. By day 6, IGFBP-2-overexpressing cells

SUBMITTER: Xi G 

PROVIDER: S-EPMC5117190 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature