Differentiation of mesenchymal stem cells into adipocyte lineage: Role of cytoskeleton-associated proteins

Abstract

Mesenchymal stem cells (MSCs) are a heterogeneous population of stem/progenitor cells that can differentiate into a variety of cell types, including osteoblasts, adipocytes, chondrocytes, and myocytes. Commitment of stem cells to these different lineages is regulated by many cues in the local tissue microenvironment. Recently, it has been demonstrated that cell shape might regulate commitment of human mesenchymal stem cells (hMSCs) to adipocyte, i.e. unspread/round hMSCs are allowed to develop into adipocytes. Evidences indicate that MSC with changes in cytoskeletal tension and disorganizing the actin cytoskeleton, or microtubule depolymerization enforcing cell rounding promotes adipogenesis. Members of the evolutionarily conserved Rho family of small GTPases are essential regulatory components of signaling pathways that direct the organization of the cytoskeleton. The apparent role of cell shape in MSC lineage commitment or adipogenic-osteogenic switch in hMSC is mediated through the RhoA-ROCK signaling pathway, and the proteins which affect the stability of cytoskeleton also contribute to the commitment of adipocyte lineage.