Effects of Nd3+ and Sm3+ on the proliferation, differentiation and mineralization function of primary osteoblasts in vitro

A series of experimental methods including 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide (MTT) test, alkaline phosphatase (ALP) activity measurement, Oil Red O stain and measurement, mineralized function expression and quantitive real time RT-PCR (qRT-PCR) were employed to assess the effect of Nd3+ and Sm3+ on the proliferation, differentiation and mineralization function of primary osteoblasts (OBs) in vitro at cell and molecular levels. The experimental results suggest that concentration, culture time and ion species are pivotal factors for switching the biological effects of rare earth ions from toxicity to activity, from damage to protection, or from down-regulation to up-regulation.