Comparative analysis of uninduced and neuronally-induced human dental pulp stromal cells in a 6-OHDA model of Parkinson's disease.

BACKGROUND: In recent years, dental pulp stromal cells (DPSCs) have emerged as a promising therapeutic approach for Parkinson's disease (PD), owing to their inherent neurogenic potential and the lack of neuroprotective treatments for this condition. However, uncertainties persist regarding the efficacy of these cells in an undifferentiated state versus a neuronally-induced state. This study aims to delineate the distinct therapeutic potential of uninduced and neuronally-induced DPSCs in a rodent model of PD induced by 6-Hydroxydopamine (6-OHDA). METHODS: DPSCs were isolated from human teeth, characterized as mesenchymal stromal cells, and induced to neuronal differentiation. Neuronal markers were assessed before and after induction. DPSCs were transplanted into the substantia nigra pars compacta (SNpc) of rats 7 days following the 6-OHDA lesion. In vivo tracking of the cells, evaluation of locomotor behavior, dopaminergic neuron survival, and the expression of essential proteins within the dopaminergic system were conducted 7 days postgrafting. RESULTS: Isolated DPSCs exhibited typical characteristics of mesenchymal stromal cells and maintained a normal karyotype. DPSCs consistently expressed neuronal markers, exhibiting elevated expression of ßIII-tubulin following neuronal induction. Results from the animal model showed that both DPSC types promoted substantial recovery in dopaminergic neurons, correlating with enhanced locomotion. Additionally, neuronally-induced DPSCs prevented GFAP elevation, while altering DARPP-32 phosphorylation states. Conversely, uninduced DPSCs reduced JUN levels. Both DPSC types mitigated the elevation of glycosylated DAT. CONCLUSIONS: Our results suggested that uninduced DPSCs and neuronally-induced DPSCs exhibit potential in reducing dopaminergic neuron loss and improving locomotor behavior, but their underlying mechanisms differ.

Dental Pulp from Human Exfoliated Deciduous Teeth-derived Stromal Cells Demonstrated Neuronal Potential: In Vivo and In Vitro Studies.

BACKGROUND: Mesenchymal Stromal Cells (MSC) have the potential for self-renewal and differentiation in different tissues, characteristics that encourage their use in regenerative medicine. Dental tissue MSCs are easy to collect, have the same embryonic origin as neurons and have neuronal markers that allow their use in treating neurodegenerative diseases. Human Exfoliated Deciduous teeth (SHED)-derived stromal cells are considered immature and present positive expression of pluripotency and neuronal markers. Studies have shown that after the induction of neuronal differentiation in vitro, SHED increased the expression of neuronal markers, such as ßIIItubulin, nestin, GFAP, NeuN, and NFM, demonstrating the potential use of these cells in preclinical studies. The results of this review reflect the consensus that in diseases such as spinal cord injury, cerebral ischaemia, and Alzheimer's and Parkinson's disease, SHED could function in the suppression of the inflammatory response, neuroprotection, and neuronal replacement. CONCLUSION: For these cells to be used in large-scale clinical trials, standardization of the isolation techniques and theneuronal induction medium are necessary. The potential of SHED to induce neuronal differentiation is evident, demonstrating that this resource is promising and shows great potential for use in future preclinical and clinical trials of neurodegenerative diseases.