Resumen de Dose-Dependent Effects of Platelet Gel Releasate on Activities of Human Osteoblasts
Jacopo Uggeri, Silvana Belletti, Stefano Guizzardi, Rita Gatti
Background: Platelet-rich plasma is used in oral and maxillofacial surgery; however, its real efficacy is debated. Also, the in vitro effects on bone-specific functions are contradictory. Understanding the mechanisms of action of platelet-derived factors could be the basis for their proper use in clinical applications.
Methods: The functional parameters of osteoblasts (proliferation, alkaline phosphatase, collagen synthesis, and calcium deposition) were analyzed in vitro for 14 days in the presence of different concentrations (100%, 33%, and 11%) of platelet gel releasate (PGR).
Results: Concentrations of 100% PGR and 33% PGR stimulated cells to proliferate more than 10% fetal calf serum. The effect on cell proliferation was dose dependent, and the addition of dexamethasone (dex) and β-glycerophosphate (β-GP) reduced the proliferative effects. Alkaline phosphatase activity was stimulated by 33% PGR and 11% PGR after 7 days and was induced further by dex and β-GP. Also, collagen synthesis, measured on day 11, was stimulated by 33% PGR and 11% PGR. Calcium deposition, evaluated after 7 and 14 days, was greatest in cells treated with PGR supplemented with dex and GP. The mineralization process increased with time; on day 14, calcium aggregates were observed in all cultures treated with PGR (100%, 33%, and 11%).
Conclusions: PGR stimulated osteoblast proliferation in a dose dependent manner and, when used at 33% and 11%, induced maximum levels of alkaline phosphatase and collagen synthesis. Moreover, in the presence of dex and β-GP, PGR stimulated the end maturative status of cells as expressed by the deposition of calcium nodules.
