Hormones and dentistry: a two-way relationship.

Stem cells of dental pulp (SCDPs) are multipotent stem cells with the potential to differentiate into various cell types. For this reason, they have been proposed as an alternative source for mesenchymal stem cells. Somatostatin (ST) is a peptide hormone with an inhibitory effect on several endogenous hormones. The aim of our study is to investigate whether somatostatin can promote or inhibit differentiation of SCDPs in osteoblasts and bone tissue. SCDPs were extracted from third molars of healthy subjects and were treated with ST at the concentration of 100 ng/ml for 24 and 48 h. Gene expression in treated SCDPs was compared with untreated cells (control) to check the effect of somatostatin on stem cell differentiation. After 24 h of treatment many genes investigated were downregulated in treated SCDPs vs untreated SCDPs. Significantly up-regulated gene (Fold change >2) was the Bone Morphogenetic Protein BMP4. On the contrary ST induced the over-expression of bone related genes after 48 h of treatment. TGFB family genes and their receptors were also significantly upregulated after 48 h of treatment. ST demonstrated to promote the self-renewal of SCDPs: in our experiments somatostatin mainly acted on TGFB family genes. Further studies are needed to explore this new way of creating bone tissue.