ABSTRACT
Stem cells from Human Exfoliated Deciduous teeth [SHED] have the capability to differentiate into neural cells. Neurotrophins including Nerve Growth Factor [NGF], Brain-Derived Neurotrophic Factor [BDNF], neurotrophin-3 [NT-3], and neurotrophin-4 [NT-4] have neurogenesis, neurotrophic, or neuroprotective effects and are expressed in developing teeth. The aim of this study was to measure quantitative changes in mRNA expression levels of neurotrophins in neural-like cells differentiated from dental pulp stem cells. Isolated total RNA from SHED, dental pulp and neural-like cells [n=3] were transcribed into cDNA. Then real time PCR was done. Expression levels of mRNA for NGF, BDNF, NT-3, and NT-4 genes were compared in these three cells. In neural like cells, BDNF mRNA increased [372.1 +/- 113.5] significantly [p<0.01] after differentiation. NGF mRNA increased to more than 266 times the dental pulp level after differentiation. A similar pattern was seen for the expression of NT3 after differentiation. NT4 mRNA enhancement was 1344 +/- 630.8 and 30.7 +/- 7.9 fold in neural like cells and SHED cells, respectively. Results show alterations with different degrees and direction in neurotrophins mRNA expression levels in these cells. Our results suggest that neurotrophins dental pulp cells, SHED cells and neural like cells derived from SHED cells produce neurotrophic factors. Since the large amounts of neurotrophins are expressed in SHED and neural like cells they may have important role in survival and differentiation of dental pulp stem cells and obtained information may lead to a novel method for tooth regeneration