Respuesta de preosteoblastos a compuestos de estroncio o calcio: proliferación, diferenciación, mineralización y respuesta génica global

Summary Background: The mechanisms which trigger osteogenesis are not yet clear. The objective of this study was to evaluate the role of strontium and calcium, provided in different molecular forms, as inductors of different mechanisms of osteoblast stimulus, including proliferation, differentiation and mineralisation of preosteoblast cells. The whole genomic response was also investigated using the microarray technique. Methods: An experimental study was designed with murine preosteoblast cells MC3T3-E1, which were stimulated for 3 hours and 7 days. Biochemical and genome gene expression studies of mouse (Affymetrix) were carried out. Results: Strontium bonded with ranelate (SrRn) was the most powerful inductor of the capacity of mineralisation in comparison with the other compounds used (2.55 times that of the control). The studies of whole gene expression showed that after 3 hours 2030 genes change, of which 1644 are specific to this phase. On the other hand, after 7 days of treatment only 329 genes change, of which 147 are specific. The biological processes most enriched after 3 hours are those involved in the regulation of transcription (147 genes), metabolic processes (140 genes) and protein phosphorylation (44 genes) among others, while at 7 days these are changes relating to the cell cycle (18 genes) and carbohydrate metabolism in general (12 genes). Conclusion: Strontium bonded with the ranelate anion performed as the most powerful inductor of osteogenesis compared with other anions such as chloride or the hydroxides. The stimulation for 3 hours showed greater changes in gene expression in comparison with 7 days. The biological processes affected may be useful in speculating on the signalling cascades involved in the activation of the osteoblast, and on new molecular targets for therapeutic purposes.