Can growth hormone influence dental pulp stem cells differentiation? A puzzle that is going to complete

Abstract

Growth hormone (GH) is a powerful and important hormone secreted by the cells of the anterior pituitary gland, influenced by many physiological and pathological conditions. Dental pulp stem cells (DPSCs) may be a source of differentiated cells inducing bone formation and controlled hydrossyapatite crystal growth. These DPSCs have the ability of self-expandig and differentiating in pre-osteoblast producing in vitro autologous bone tissue. The aim of our study is to investigate if GH can influence differentation of DPSCs in osteoblats and bone tissue. Gene related to ossification (BMP1, BMP2 BMP3, BMP4, BMP5 BMP6), osteoblast differentiation (BMPR1A, BMPR1B, BMPR2), bone mineralization (TGFB1, TGFB2, TGFB3) and skeletal development (TGFBR1 AND TGFBR2) were investigated to study the potential effect of GH in osteoblast differentiation and proliferation. After 24 h of treatment all gene investigated were up-regulated in treated DPSCs vs. untreated DPSCs. Significant up-regulated genes (Fold change > 2) were the Bone Morphogenetic Protein BMP2, BMP4, BMP6 and BMP7. GH induce the over-expression of bone related genes after 48 h of treatment too. In this case the significant up-regulated genes were the Bone Morphogenetic Protein BMP3, BMP4, BMP5 and their receptor BMPR1B and BMPR2. Transforming Growth Factor Genes family (TGFB1, TGFB2, TGFB3) and their receptor (TGFBR1 and TGFBR2) are also significantly up-regulated after GH treatment. GH has demonstrated to influence this process of DPSCs differention and expansion in osteoblats. Further studies are needed to explore this new way of creating bone tissue.