EFFECT OF DESFERRIOXAMINE AND DEFERIPRONE (L1) ON THE PROLIFERATION OF MG-63 BONE-CELLS AND ON PHOSPHATASE ALKALINE ACTIVITY

In the present work, we studied: (i) the effect of different doses of desferrioxamine and deferiprone on the proliferation of osteoblasts an d the possible role of iron in this; and (ii) the effect of both chela tors on the metabolic activity of these cells, using the quantificatio n of alkaline phosphatase as an enzymatic marker of cellular activity or differentiation. Cellular proliferation was investigated at differe nt concentrations of deferiprone and desferrioxamine, and the effect o f the addition of iron citrate on this proliferation was measured. The production of alkaline phosphatase after incubation with deferiprone (150 and 300 mu M) and desferrioxamine (20 and 100 mu M) was also stud ied. Cellular proliferation was completely inhibited with 100 mu M of desferrioxamine and 300 mu M of deferiprone. In both cases, this effec t was corrected by means of co-incubation with iron citrate. In the se cond phase, using the same dose that inhibited the proliferation, it w as observed that after 24 h, both chelators slightly decreased alkalin e phosphatase activity, while at 48 and 96 h they increased alkaline p hosphatase activity. These results demonstrate that both desferrioxami ne and deferiprone inhibit the proliferation of the osteoblast-like ce ll line MG-63; the effect seems to be related to the chelation of some fraction of available iron. In spite of the effect on bone cell proli feration, the chelators do not impair cellular activity.