Osteogenic Differentiation Factors of Multipotent Mesenchymal Stromal Cells in the Current Understanding

Background: Molecular genetic mechanisms, signaling pathways, conditions, factors, and markers of the osteogenic differentiation of mesenchymal stem cells (MSCs) are being actively studied and are among the most studied areas in the field of cellular technology. This attention is largely due to the mounting contradictions in the seemingly classical knowledge and the constant updating of results in the analyzed areas. In this regard, we focus on the main classical concepts and some new factors and mechanisms that have a noticeable regulatory effect on the differentiation potential of postnatal MSCs. Results: This review considers the importance of the sources of MSCs for the realization of their differentiation potential, molecular genetic factors and signaling pathways of MSC differentiation, the role of inflammatory cytokines and chemokines in osteogenesis, biomechanical signals, and the effect of conformational changes in the cellular cytoskeleton on MSC differentiation. Conclusion: It is concluded that it is necessary to move from studies focused on the effects of local genes to those taking multiple measurements of the gene-regulatory profile and the biomolecules critical for the implementation of numerous, incompletely studied osteogenic factors of endogenous and exogenous origin. Among the cornerstones of future (epi)genetic studies, whether osteomodulatory effects are realized through specific signaling pathways and/or whether cross-signaling with known genes drives the osteogenic differentiation of MSCs remains to be determined.