Basic fibroblast growth factor (FGF-2), an important modulator of cartilage and bone growth and differentiation, is expressed and regulated in osteoblastic cells. To investigate the role of FGF-2 in bone, we examined mice with a disruption of the Fgf2 gene. Measurement of trabecular bone architecture of the femoral metaphysis of Fgf2+/+ and Fgf2–/– adult mice by micro-CT revealed that the platelike trabecular structures were markedly reduced and many of the connecting rods of trabecular bone were lost in the Fgf2–/– mice. Dynamic histomorphometry confirmed a significant decrease in trabecular bone volume, mineral apposition, and bone formation rates. In addition, there was a profound decreased mineralization of bone marrow stromal cultures from Fgf2–/– mice. This study provides strong evidence that FGF-2 helps determine bone mass as well as bone formation.
Aldemar Montero, Yosuke Okada, Masato Tomita, Masako Ito, Hiroshi Tsurukami, Toshitaka Nakamura, Thomas Doetschman, J. Douglas Coffin, Marja M. Hurley
Static histomorphometric parameters of bone structure at right proximal tibia in 4.5-month-old