Effect of strontium ranelate on hydrogen peroxide-induced apoptosis of CRL-11372 cells

In vitro and in vivo studies have proven strontium to be an osteoinductive trace element. The effect of strontium ranelate (SR) on H(2)O(2)-induced apoptosis of CRL-11372 cells and optimization of its anti-apoptotic dose were the aims of this study. After 1 h of pretreatment with SR 1 microM, 50 microM, 100 microM, 500 microM, and 1,000 microM concentrations, CRL-11372 osteoblasts were exposed to 100 microM H(2)O(2) for periods of 6-12 h. The same experiments were repeated without H(2)O(2). The apoptotic index and viability of cells were assessed quantitatively with a fluorescent dye and qualitatively with agarose gel electrophoresis. Concentrations of 1-100 microM of SR with a 6-h treatment and only 1 microM concentration with a 12-h treatment inhibited the apoptotic effect of H(2)O(2) on cultured osteoblasts significantly (P < 0.05). SR was shown to inhibit H(2)O(2)-induced apoptosis of CRL-11372 cells in a dose-dependent manner.