RESUMO
BACKGROUND:Angiotensin II receptor antagonists have been found to exerct a stronger protective effect on bone than angiotensin converting enzyme inhibitors. OBJECTIVE:To investigate the effect of different concentrations of irbesartan (angiotensin II receptor antagonist) on the differentiation and mineralization of mouse preosteoblasts. METHODS:Mouse preosteoblast cel lines MC3T3-E1 in logarithmic phase were selected and cultured in the osteogenic induction medium containing 0 (control group), 0.001, 0.01, 0.1 mmol/L irbesartan, respectively. Ten days later, the cel differentiation was observed by alkaline phosphatase staining. The mineralization was observed by alizarin red staining after 21 days of culture. mRNA expressions of osteocalcin, alkaline phosphatase and Runt-associated transcription factor 2 in osteoblasts were detected by real-time PCR at 1, 4, 7, 14 and 21 days of culture. RESULTS AND CONCLUSION:The activity of alkaline phosphatase in al the irbesartan groups (0, 0.001, 0.01, 0.1) was higher than that in the control group (P<0.05), which was the most obvious in 0.01 mmol/L. The number and area of calcium nodules in each irbesartan group were significantly higher than those in the control group (P<0.05), especial y in 0.01 mmol/L. Compared with the control group, 0.01 mmol/L irbesartan significantly upregulated the mRNA expressions of osteocalcin, alkaline phosphatase and Runt-associated transcription factor 2 (P<0.05). These results suggest that 0.01 mmol/L irbesartan significantly promotes the differentiation and mineralization of osteoblasts.
