Review
Copyright ©The Author(s) 2019.
World J Stomatol. Jan 15, 2019; 7(1): 1-19
Published online Jan 15, 2019. doi: 10.5321/wjs.v7.i1.1
Table 1 Studies retrieved from PubMed database evaluating the effect of DPSCs on peripheral nerve repair or regeneration both in-vivo and in-vitro
Author (publication year)Source of stem cellsTarget tissueStudy modelObjectiveOutcome
Carnevale et al[14], 2018In-vivoHuman STRO-1+ /c-Kit+ /CD34+DPSCs expressing P75NTR, nestin and SOX-10Sciatic nerve defectAnimal rat modelTo demonstrate the ability of human STRO-1+ /c-Kit+ /CD34+ DPSCs expressing P75NTR, nestin and SOX-10 to promote axonal regeneration.The cells promoted regeneration and functional recovery of sciatic nerve defects after injury.
In-vitroHuman STRO-1+ /c-Kit+ /CD34+DPSCs expressing P75NTR, nestin and SOX-10To differentiate into SC-like cellsIn-vitro culturing of DPSCs and their differentiation to SCsTo demonstrate the ability of Human STRO-1+ /c-Kit+ /CD34+ DPSCs expressing P75NTR, nestin and SOX-10 to differentiate into SC-like cells.Under appropriate conditions, the cells differentiated into SC-like cells
Kolar et al[75], 2017In-vivoAdult rat SCs; Human SCAP, DPSCs and PDLSC10 mm nerve gap defect in a rat sciatic nerveSciatic nerve injury modelTo demonstrate the ability of human SCAP, DPSCs and PDLSC to promote axonal regeneration using nerve guidance conduit of 14 mm length.All the stem cell types significantly enhanced axon regeneration after two weeks. SCAP are the optimal dental stem cell type for peripheral nerve repair.
In-vitroCM from unstimulated or stimulated human SCAP, DPSCs and PDLSCDifferentiated human neuroblastoma SH-SY5Y cell lineIn-vitro neurite outgrowth assayTo examine the biological activity of the conditioned medium for unstimulated and stimulated human SCAP, DPSC and PDLSC.Quantification of the neurite outgrowth showed that unstimulated and stimulated human SCAP, DPSCs and PDLSC increased both the percentage of cells producing neurites and the total neurite outgrowth length.
Omi et al[76], 2017In-vivoDPSCs isolated from the incisor teeth of 6-wk-old male ratsSciatic nerve; Sensory nerve fibers; Sural nervesStreptozotocin-induced diabetic rats.Investigated whether the transplantation of DPSCs ameliorated long-term diabetic polyneuropathy in streptozotocin-induced diabetic rats.Significant reductions in the sciatic motor/sensory nerve conduction velocity, increases in the current perception threshold, and decreases in capillary density in skeletal muscles and intra-epidermal nerve fiber density. Sural nerve morphometrical analysis revealed that the transplantation of DPSCs significantly increased the myelin thickness.
In-vitroDPSCs isolated from the incisor teeth of 6-wk-old male ratsDorsal root ganglion neuron were cultured for use in neurite outgrowth with DPSC-CM; Immortalized adult Fischer rat SCs were cultured with DPSC-CMIn-vitro neurite outgrowth assay; Cell viability assayEvaluation of neurite outgrowth. Analysis of myelin-related protein formation in immortalized adult Fischer rat SCs.DPSCs-CM promoted the neurite outgrowth of dorsal root ganglion neurons. Increased the viability and myelin-related protein expression of SCs.
Sanen et al[77], 2017In-vivoSCs derived from differentiated human DPSCs15-mm rat sciatic nerve defectsSciatic nerve injury modelEvaluated the performance of SCs derived from differentiated human DPSCs in a rat model of PNI.Immunohistochemistry and ultrastructural analysis revealed in-growing neurites, myelinated nerve fibres and blood vessels along the construct.
In-vitroSCs derived from differentiated human DPSCsHuman microvascular endothelial cell line (HMEC-1)Alamar Blue cell proliferation assay; Transwell migration assay; Tube formation assayInvestigated the neuroregenerative and the proangiogenic capacities of SCs derived from differentiated human DPSCs.The endothelial cell line HMEC-1 had proliferated significantly more in the presence of conditioned medium from human DPSCs and differentiated human DPSCs compared with those in control medium.
Hei et al[78], 2016In-vivoSchwann-like cells were derived from human DPSCs; Human DPSCs3 mm - wide crush injury was inflicted at a distance of approximately 10 mm from the mental foramenMale Sprague-Dawley rats crush-injury siteTo investigate the effect of Schwann-like cells combined with pulsed electromagnetic field on peripheral nerve regeneration.Schwann-like cells, human DPSCs with or without pulsed electromagnetic field, and pulsed electromagnetic field only improved peripheral nerve regeneration.
In-vitroSchwann-like cells were derived from human DPSCs; Human DPSCsSchwann CellsCell culture dishesTo demonstrate the ability of hDPSCs to differentiate into Schwann - like cells and demonstrate glial character with expression of CD104, S100, GFAP, laminin and p75NTR.Successful morphological differentiation of hDPSCs toward Schwann - like cells.
Yamamoto et al[79], 2016In-vivoHuman mobilized DPSCs5-mm gap of the left sciatic nerveRat sciatic nerve defect modelTo investigate the effects of human mobilized DPSC transplantation on peripheral nerve regeneration using 9-mm collagen conduit.Human mobilized DPSCs promote axon regeneration through trophic functions, acting on SCs and promote angiogenesis.
In-vitroCM of human mobilized DPSCsRat SCs (RT4-D6P2T)Migration, proliferation, and anti-apoptotic assaysTo investigate the trophic effects of mobilized human DPSCs on proliferation, migration and anti-apoptosis in SCsThe human mobilized DPSCs-CM significantly enhanced proliferation and migratory activity and decreased apoptosis of RT4-D6P2T cells.
Askari et al[80], 2014In-vivoHuman DPSCs transfected with a tetracycline-inducible system expressing oligodendrocyte lineage transcription factor 2 geneSciatic nerve demyelination experimentMouse model of local sciatic demyelination damage by lysolecithinTo investigate if the tetracycline-regulated expression of oligodendrocyte lineage transcription factor 2 gene transfected in human DPSCs can lead to mouse sciatic nerve regeneration upon transplantation.Human DPSCs-derived oligodendrocyte progenitor cells have relevant therapeutic potential in the animal model of sciatic nerve injury.
In-vitroHuman DPSCsOligodendrocyteIn-vitro plasmid construct and transfectionDPSCs were transfected with oligodendrocyte transcription factor 2 which play important role in differentiation of DPSCs to oligodendrocyte progenitor cells.Exogenous expression of the oligodendrocyte lineage transcription factor 2 gene by a tetracycline-regulated system could be used as an efficient way to induce the differentiation of DPSCs into functional oligodendrocytes.
Dai et al[81], 2013In-vivoSCs, AMSCs, DPSCs, and the combination of SCs with AMSCs or DPSCs15-mm-long critical gap defect of rat sciatic nerveSciatic nerve injury modelTo test their efficacy in repairing PNI 17-mm nerve conduit.Co-culture of SCs with AMSCs or DPSCs in a conduit promoted peripheral nerve regeneration over a critical gap defect.
In-vitroSCs, AMSCs, DPSCs, and the combination of SCs with AMSCs or DPSCsNeuronal cellsRT-PCR analysis of the coculture in-vitroTo verify if the combination of cells led to synergistic neurotrophic effects NGF, BDNF, and GDNF.Results confirmed the synergistic NGF production from the co-culture of SCs and ASCs.
Table 2 Studies retrieved from PubMed database evaluating the effect of DPSCs on nerve repair or regeneration in-vivo
AuthorPublication yearSource of stem cellsTarget nervesStudy modelObjectiveOutcome
Ullah et al[82], 20172017Human DPSCs; Differentiated neuronal cells from DPSCs5-mm gap sciatic nerve transectionAnimal rat modelTo evaluate the in-vivo peripheral nerve regeneration potential of human DPSCs and differentiated neuronal cells from DPSCs.In-vivo transplantation of the undifferentiated hDPSCs could exhibit sufficient and excellent peripheral nerve regeneration potential.
Spyridopoulos et al[83], 20152015DPSCs isolated from second lateral incisor pigsTransected fifth and sixth intercostal nervesAnimal pig modelExamined the potential of DPSCs for peripheral nerve regeneration, using biodegradable collagen conduits.The nerves where DPSCs were injected exhibited morphological and functional recovery.
Table 3 Studies retrieved from PubMed database evaluating the effect of DPSCs on nerve repair or regeneration in-vitro
AuthorPublication yearSource of stem cellsTarget tissuesObjectiveOutcome
Geng et al[84], 20172017Human DPSCsDifferentiation of hDPSCs.To demonstrate the differentiating ability of resveratrol on DPSCs.Resveratrol induced DPSCs differentiation into neuroprogenitor cells. DPSCs might be an important cell population for neurological disease treatment.
Hafner et al[85], 20172017Human DPSCsSpider dragline silk fibersTo evaluating adhesion and alignment of dental pulp stem cells to a spider silk substrate for tissue engineering applications.Natural drawn spider silk acted as an effective substrate for cellular adhesion and alignment of DPSCs and could be used in neural differentiation applications.
Chang et al[86], 20142014Human DPSCsMedium preparation for the induction of spinal motor neuronal differentiation; Medium preparation for the induction of dopaminergic neuronal differentiationTo evaluate the efficacy of dopaminergic and motor neuronal inductive media on transdifferentiation of human DPSCs (hDPSCs) into neuron-like cells.Human DPSCs-derived dopaminergic and spinal motor neuron cells after induction expressed a higher density of neuron cell markers than those before induction.
Mead et al[60], 20142014Human DPSC, human BMSCs human AMSCsAxotomised adult rat retinal ganglion cellsTo evaluate the therapeutic potential for neurodegenerative conditions of retinal ganglion cells.Human DPSCs promoted significant multi-factorial paracrine-mediated retinal ganglion cell survival and neurite outgrowth compared with Human BMSCs/Human AMSCs.
Martens et al[23], 20142014Human DPSCsDorsal root gangliaEvaluated the differentiation potential of human DPSCs toward SCs, together with their functional capacity with regard to myelination and support of neurite outgrowth.Human DPSCs are able to undergo SCs differentiation and support neural outgrowth.