Notch-dependent activation of periodontal cells osteogenic potential

Abstract

Background and objective . Periodontal stem cells are a promising material for dentistry and maxillofacial surgery. In this work, we sought to find out how Notch signaling pathway affects the osteogenic potential of periodontal ligament stem cells (PDLSC). Design and methods . In order to verify this, we used lentiviral transduction of PDLSC, adding various amounts of the virus bearing the activated intracellular domain of the Notch1 receptor, NICD. Using real-time PCR, we analyzed the dependence of changes in the expression levels of osteo-markers ( RUNX2, COL1A1, OGN, POSTN ) on the activation strength of Notch signaling pathway, based on the expression of the target gene — HEY1 , in the early stages of differentiation, after 48 and 120 hours after induction of osteogenic differentiation. In addition, using the technique of Alizarin red extraction, we were able to quantify the intensity of mineralization of periodontal MSCs at the final stage of osteogenic differentiation. Results . We found that activation of Notch signaling pathway leads to increased expression of osteogenic markers in the early stages of osteogenic differentiation induction, which in turn leads to the development of the final stage of osteogenic differentiation, characterized by the formation of calcification. Moreover, the more intensive the initial level of Notch, the stronger and more effective were the processes of osteogenesis. Conclusion . In this work, we showed that activation of Notch signaling pathway leads to an increase in the osteogenic potential of periodontal PDLSC in a dose-dependent manner and induces in the cells processes associated with the accumulation of calcifications, the intensity of formation of which directly depends on the “strength” of Notch signal. The results obtained in this work convince us that Notch is able to modulate osteogenic differentiation, affecting its effectiveness, apparently due to the strength of the signal that is transmitted to the cells.