Insulin activity on dental pulp stem cell differentiation: An in vitro study

Insulin is a powerful and important hormone involved in the proliferation and differentiation of osteoblasts. Dental pulp stem cells (DPSCs) have the ability to self-expand and differentiate in preosteoblast, producing in vitro autologous bone tissue. The aim of our study is to investigate whether insulin can influence differentiation of DPSCs in osteoblast and bone tissue. Dental germ pulp was extracted from third molars of healthy subjects, following informed consent. DPSCs were treated with insulin at the concentration of 100 ng/μl for 24 and 48 h. Gene expression in treated DPSCs was compared with untreated cells (control) in order to check the effect of insulin on stem cell differentiation. After 24 h, significant up-regulated genes (Fold change > 2) in DPSCs were the Bone Morphogenetic Proteins BMP3, BMP4 and their receptor BMPR1A. BMP1 results over-expressed after 48 h of treatment. Significantly down-regulated genes were BMP4, BMP7 and TGFBR2 after 24 h of treatment and BMP5 and BMP7 after 48 h. Insulin was demonstrated to influence proliferation of DPSC, differentiation and expansion in osteoblasts. Further studies are needed to explore this new way of creating bone tissue.