Neural Differentiation of Human Dental Mesenchymal Stem Cells Induced by ATRA and UDP-4: A Comparative Study

Abstract

Human mesenchymal stem cells (MSC) are multipotent stem cells, which are isolated from various sources. Currently, there is a worldwide interest for dental MSC to be used against neurodegenerative diseases, since they derive from the neural crest and express embryonic stem cell markers. This fact prompted us to explore their potential for neural trans-differentiation in culture. We employed all-trans-retinoic acid (ATRA) and 2-(3-ethylureido)-6-methylpyridine (UDP-4) to induce neural differentiation of human MSC from the dental apical papilla (SCAP). The SCAP were exposed to either agent separately and assessed for proliferation, viability, morphology, and gene expression of the following neural-specific markers: neuron-specific enolase (ENO2), neurofibromin 1 (NF1), choline acetyltransferase (CHAT), tyrosine hydroxylase (TH), and the vesicular GABA transporter (SLC32A1). They were also assessed for the expression of glial fibrillary acidic protein (GFAP) and neuronal nuclear antigen (NeuN) by immunofluorescence. ATRA or UDP-4 treatment inhibited the cell growth and promoted limited cell death, but to a different extent. The addition of the neuroprotective agent recombinant human erythropoietin-alpha (rhEPO-α) enhanced the UDP-4-inducing capacity for more than three weeks. ATRA or UDP-4 treatment significantly upregulated ENO2 and NF1 expression, indicating neuronal differentiation. Moreover, the ATRA treatment significantly induced the upregulation of the GABAergic-specific SLC32A1, while the UDP-4 treatment led to the significant upregulation of the adrenergic-specific TH. The UDP-4 treatment induced the expression of NeuN and GFAP after four and three weeks, respectively, while the ATRA-treatment did not. Our findings indicate that SCAP can be differentiated into neural-like cells after treatment with ATRA or UDP-4 by exhibiting a disparate pattern of differentiation. Therefore, UDP-4 is suggested here as a new potent neural-differentiation-inducing compound, which, when combined with rhEPO-α, could lay the foundation for robust stem-cell-based therapies of neurodegeneration.

Exploring the neurogenic differentiation of human dental pulp stem cells

“…The ATRA is commonly used to induce neurogenic differentiation of multiple cell lines and stem cells such as SH-SY5Y human neuroblastoma cells [107,108], P19 mouse embryonal carcinoma cell line [109,110], embryonic stem cells [111,112], and mesenchymal stem cells [113]. However, Takahashi et al [114] and Goldie et al, [74] reported that ATRA alone results in immature neural differentiation of SH-SY5Y and neural stem cells and should be supplemented in combination with neurotrophin such as BDNF to establish full neural maturation.…”

Mesenchymal Stromal Cells Derived from Dental Tissues: Immunomodulatory Properties and Clinical Potential

“…Howeve differences have been observed in other characteristics, such as the immunophenotyp where the expression of some markers may vary. In addition, although they have simil multipotentialities for differentiation toward chondrocytes and osteoblasts, the adipogenic capacity is lower than that of other tissues, such as BM [58,60,61,62,63,64 Moreover, D-MSCs derived from neural crest cells possess an increased potential f differentiation into neural cells [65,66,67,68]. Taken together, these findings indicate th The most common methods used to obtain MSCs are explant and enzymatic digestion.…”

“…In addition, although they have similar multipotentialities for differentiation toward chondrocytes and osteoblasts, their adipogenic capacity is lower than that of other tissues, such as BM [58,[60][61][62][63][64]. Moreover, D-MSCs derived from neural crest cells possess an increased potential for differentiation into neural cells [65][66][67][68]. Taken together, these findings indicate that although all of these sources originate in related anatomical regions, the biological properties of each can vary, and of particular importance is their immunosuppressive capacity due to their relevance in clinical protocols.…”

Advancements in Spinal Cord Injury Repair: Insights from Dental-Derived Stem Cells

“…Derived from the neural crest, dental MSCs uniquely express neural markers, secrete neurotrophic factors, and combine MSC-like characteristics with immunomodulation and neural features [ 73 ]. With their neural crest lineage, neuronal markers, and expression of neurotrophic factors, along with the potential for neurogenic differentiation, these cells are actively researched for their applications in treating neuronal diseases and injuries [ 74 , 75 ]. Recent studies highlight their promising role in neural tissue engineering for nerve regeneration, particularly in the treatment of SCI.…”