Research Article

Regulation of Osteogenic Differentiation of Placental-Derived Mesenchymal Stem Cells by Insulin-Like Growth Factors and Low Oxygen Tension

Figure 8

PMSC osteogenic differentiation in the presence of IGFs and low oxygen tension. Summary diagram showing stem cell differentiation model in room air versus low oxygen. PMSCs can differentiate into osteogenic lineage only in room air, while maintaining PMSCs in low oxygen tension impedes this differentiation process. (A) In low oxygen tension, nondifferentiation conditions maintain self-renewal (higher proliferation) and IGF-2 can maintain higher expression of OCT4 and SOX2. (B) In differentiation media, PMSCs show an impeded differentiation with higher OCT4 and SOX2 and lowered RUNX2, which recovers following room air exposure. (C) In room air, spontaneous differentiation occurs with lower OCT4 and SOX2 and lower RUNX2. (D) In differentiation media, PMSCs fully differentiate towards osteoblastic progenitors with higher RUNX2 and OPN, which enhanced by IGF-1. Cell morphology and alizarin red staining increase as PMSCs lose multipotency and commit to the osteogenic lineage.