Inhibitory Effect and Cell Mechanism of BM210955 on Bone Resorption / 复旦学报（医学版）

ABSTRACT

PurposeTo investigate the mechanism of BM210955 (ibandronate, a new bisphosphonate drug manufactured in China)in the prevention of bone loss in vitro. MethodsThe osteoclasts isolated from the long bone of 10-day-old Rabbit were cultured on glass and bone slices in different concentration of BM210955. TRAP(tartrate resistant acid phosphonase) staining for osteoclast and TB( toluidine blue)staining for resorption lacunae were used on bone slices and Fluorescence (orange acridine) staining for apoptosis cell on glass slices was used;Multinucleated( three and more nuclei) TRAP positive cell and Apoptosis cell and Pits were counted. ResultsThe BM210955 decreased the multinucleated cell number by 73% in 10-8 mol/ L;The inhibitory rate of pit formed was correlate to concentration as 31.58%, 76.32% and 87.99% to 10-12, 10-10 and 10-8 mol/L; The apoptosis induction was shown in above 10-8 mol/L, and the apoptosis rate was 62% in 10-4 mol/L. Conclusions Induction of osteoclast apoptosis and decrease of the cell number and inhibition of resorptive ability were the major mechanism for bone loss prevention effect of BM210955 in vitro.