Lanthanum Enhances In Vitro Osteoblast Differentiation via Pertussis Toxin-Sensitive Gi Protein and ERK Signaling Pathway

作者：Wang Xi; Yuan Lan; Huang Jian^*; Zhang Tian Lan; Wang Kui

来源：Journal of Cellular Biochemistry, 2008, 105(5): 1307-1315.

DOI：10.1002/jcb.21932

• LA(3+)
• OSTEOBLAST
• DIFFERENTIATION
• GI PROTEIN
• ERK PATHWAY

Converging lines of evidence suggest that lanthanum tends to deposit in bone. The influence of lanthanum ion (La(3+)) on osteoblast differentiation and the related mechanism are essential to understanding its effect on bone metabolism. In this study, La(3+) treatment enhanced in vitro osteoblast differentiation as evidenced by promoting alkaline phosphatase (ALP) activity, osteocalcin (OC) secretion, and matrix mineralization. The expressions of osteoblast-specific genes of Cbfa-1, osteopontin (OPN), and bone sialoprotein (BSP) were all increased in the presence of La(3+), but no change was observed in that of type I collagen (COL-I). Further studies demonstrated that La(3+) treatment enhanced phosphorylation of extracellular signal-regulated kinase (ERK). Inhibition of ERK activation by U0126 suppressed the effects of La(3+) on osteoblast activity. Moreover, pretreatment of the cells with pertussis toxin (PTx), a Gi protein inhibitor, suppressed the La(3+)-enhanced ERK phosphorylation and osteoblast differentiation. These findings suggest that La(3+) exposure enhances in vitro osteoblast differentiation and the effect depends on ERK phosphorylation via PTx-sensitive Gi protein signaling. J. Cell. Biochem. 105: 1307-1315, 2008.

• 出版日期2008-12-1
• 单位北京大学