Abstract

This study assesses the cytoprotective effects of human dental pulp stem cells (hDPSCs) and conditioned medium from hDPSCs (CM-hDPSCs) on ischemic human astrocytes (hAs) in vitro compared with human bone marrow-derived mesenchymal stem cells (hMSCs). Ischemia of hAs was induced by oxygen-glucose deprivation (OGD). CM-hDPSCs and hMSCs were collected after 48 hr of culture. Cell death was determined by 3-[4,5-dimethylthialzol-2-yl]-2,5-diphenyltetrazolium bromide and cellular ATP assays. The expression of glial fibrillary acidic protein (GFAP) and musashi-1 as markers of reactive astrogliosis was examined with immunochemical staining. mRNA expression and reactive oxygen species (ROS) were analyzed by RT-PCR and flow cytometry, respectively. OGD increased cytotoxicity in a time-dependent manner and decreased cellular ATP content concomitantly in hAs. Pretreatment and posttreatment with hDPSCs were associated with greater recovery from OGD-induced cytotoxicity in hAs compared with hMSCs. Similarly, CM-hDPSCs had a greater effect on OGD-induced cytotoxicity in a dose-dependent manner. Pre- and posttreatment with CM-hDPSCs or CM-hMSCs attenuated OGD-induced GFAP, nestin, and musashi-1 expression in hAs. Furthermore, treatment ofcells with CM-hDPSCs and hMSCs blocked OGD-induced ROS production and interleukin-1ß upregulation. This study demonstrates for the first time that hDPSCs and CM-hDPSCs confer superior cytoprotection against cell death in an in vitro OGD model compared with hMSCs as shown by cell viability assay. Reactive gliosis, ROS production, and inflammatory mediators might contribute to this protective effect. Therefore, hDPSCs could represent an alternative source of cell therapy for ischemic stroke

http://www.ncbi.nlm.nih.gov/pubmed/25663284/

Abstract

Mesenchymal stem/stromal cells (MSCs) have a wide application in cell based therapies and tissue engineering. In the present study, the differentiation, survivin (SVV) modified effects and molecular basis of human umbilical cord derived MSCs (HUMSCs) and dental pulp derived stem cells (DPSCs) were investigated. The HUMSCs were found to differentiate into adipocytes more readily than the DPSCs and the HUMSCs and DPSCs were each able to differentiate into osteoblasts and chondroblasts. Following modification of the MSCs by SVV, the secretion of SVV in the modified HUMSCs was significantly higher compared with that in the modified DPSCs. In vivo, survival of the SVV modified DPSCs was observed at 4 and 14 days after intrastriatal transplantation, as was the expression of SVV and differentiation into astrocytes. The gene expression profiles of the control and modified HUMSCs and DPSCs were compared using RNA sequencing and an association was observed between gene expression and variability in cell line function. These findings provide novel information regarding the differences between HUMSCs and DPSCs and insight into optimal cell sources for therapeutic applications.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4368085/pdf/mmr-11-05-3269.pdf /

Abstract

Several models of tissue-engineered human skin based on three-dimensional (3D) co-culture techniques have been proposed to the date. However, normal skin biopsies are not always available, especially in patients with a high percentage of skin affected by deep burning, and the generation of large amounts of cultured keratinocytes may take very long time, with an associated risk for the patients' survival. For those reasons, the search of alternative cell sources for tissue reconstruction is a clinical need. In this context, Human Dental Pulp Stem Cells (HDPSC) have the potential to differentiate into multiple cell lineages by the appropriate differentiation conditions, but skin epidermis differentiation has not been demonstrated so far. Here, we hypothesize that HDPSC may have pluripotent differentiation capability, and may be able to differentiate into skin epithelial keratinocytes in culture using organotypic 3D models based on the interaction with the subjacent dermal fibroblasts. By using HDPSC, the problems associated to the donor site availability and the proliferation capability of the epithelial cells could be solved. The rapid accessibility to these cells could be translated to a more immediate generation of a bioengineered human skin substitute for the future clinical treatment.

http://www.ncbi.nlm.nih.gov/pubmed/25764965/

Abstract

This review summarizes the biological response of dentin-pulp complexes to a variety of stimuli and responses to current treatment therapies and reviews the role of tissue engineering and its application in regenerative endodontics. An electronic search was undertaken based on keywords using Medline/PubMed, Embase, Web of Science and Ovid database resources up to March 2012 to identify appropriate articles, supplemented by a manual search using reference lists from relevant articles. Inclusion criteria were mainly based on different combinations of keywords and restricted to articles published in English language only. Biological approaches based on tissue engineering principles were found to offer the possibility of restoring natural tooth vitality, with distinct evidence that regeneration of lost dental tissues is possible. Studies to formulate an ideal restorative material with regenerative properties, however, are still under way. Further research with supporting clinical studies is required to identify the most effective and safe treatment therapy.

http://www.ncbi.nlm.nih.gov/pubmed/23946258/

Abstract

OBJECTIVE:

The objectives of this study are to isolate, cultivate, and characterize stem cells from the pulp of carious deciduous teeth (SCCD) and compare them to those retrieved from sound deciduous teeth (SHED-stem cells from human exfoliated deciduous teeth).

MATERIAL AND METHODS:

Cells were obtained of dental pulp collected from sound (n = 10) and carious (n = 10) deciduous human teeth. Rate of isolation, proliferation assay (0, 1, 3, 5, and 7 days), STRO-1, mesenchymal (CD29, CD73, and CD90) and hematopoietic surface marker expression (CD14, CD34, CD45, HLA-DR), and differentiation capacity were evaluated.

RESULTS:

Isolation success rates were 70 and 80 % from the carious and sound groups, respectively. SCCD and SHED presented similar proliferation rate. There were no statistical differences between the groups for the tested surface markers. The cells from sound and carious deciduous teeth were positive for CD29, CD73, and CD90 and negative for CD14, CD34, CD45, and HLA-DR and were capable of differentiating into osteogenic, chondrogenic, and adipogenic lineages.

CONCLUSION:

SCCD demonstrated a similar pattern of proliferation, immunophenotypical characteristics, and differentiation ability as those obtained from sound deciduous teeth. These SCCD represent a feasible source of stem cells.

CLINICAL RELEVANCE:

Decayed deciduous teeth have been usually discarded once the pulp tissue could be damaged and the activity of stem cells compromised. These findings show that stem cells from carious deciduous teeth can be applicable source for cell-based therapies in tissue regeneration.

http://www.ncbi.nlm.nih.gov/pubmed/25898896/

Abstract

INTRODUCTION:

Successful isolation of mesenchymal stem cells from waste tissues might be extremely promising for developing stem cell-based therapies. This study aimed to explore whether cells retrieved from teeth extracted due to advanced periodontal disease present mesenchymal stem cell-like properties.

METHODS:

Pulp cells were isolated from 15 intact molars and 15 teeth with advanced periodontal disease. Cell proliferation and markers of mesenchymal stem cells were evaluated.

RESULTS:

Based on the RT-PCR and agarose gel electrophoresis, nucleostemin, Oct-4 and jmj2c, but not Nanog, were expressed in undifferentiated mesenchymal stem cells of both groups. Interestingly, diseased pulp exhibited higher gene expressions although it was not statistically significant. The average percentage of BrdU positive cells in the diseased group (84.4%, n = 5) was significantly higher than that of the control group (65.4%, n = 5) (t-test, P = 0.001).

CONCLUSION:

Our results indicate the successful isolation of mesenchymal stem cells from the pulp tissue of hopeless periodontally involved teeth.

http://www.ams.ac.ir/AIM/NEWPUB/15/18/4/004.pdf/

Abstract

Recently mesenchymal stem cells have demonstrated a potential for neurotrophy and neurodifferentiation. We have recently isolated mobilized dental pulp stem cells (MDPSCs) using granulocyte-colony stimulating factor (G-CSF) gradient which have high neurotrophic/angiogenic potential. The aim of this study is to investigate the effects of MDPSCs transplantation on peripheral nerve regeneration. Effects of MDPSCs transplantation were examined in a rat sciatic nerve defect model and compared with autografts and control conduits containing collagen scaffold. Effects of conditioned medium of MDPSCs were also evaluated in vitro. Transplantation of MDPSCs in the defect demonstrated regeneration of myelinated fibers, whose axons were significantly higher in density compared with those in autografts and control conduits only. Enhanced revascularization was also observed in the MDPSCs transplants. The MDPSCs did not directly differentiate into Schwann cell phenotype; localization of these cells near Schwann cells induced several neurotrophic factors. Immunofluorescence labelling demonstrated reduced apoptosis, and increased proliferation in resident Schwann cells in the MDPSCs transplant compared with control conduits. These trophic effects of MDPSCs on proliferation, migration and anti-apoptosis in Schwann cells were further elucidated in vitro. The results demonstrate that MDPSCs promote axon regeneration through trophic functions, acting on Schwann cells, and promoting angiogenesis.

http://www.ncbi.nlm.nih.gov/pubmed/25903498 /

Abstract

Although regenerative endodontic procedures have yielded an impressive body of favorable outcomes, the treatment of necrotic immature permanent teeth in particular remains to be a challenge. Recent advances in dental stem cell research have gained increasing insight in their regenerative potential and prospective use in the formation of viable dental tissues. Numerous studies already reported successful dental pulp regeneration following application of dental pulp stem cells, stem cells from the apical papilla or dental follicle precursor cells in different in vivo models. Next to responsive cells, dental tissue engineering also requires the support of an appropriate scaffold material, ranging from naturally occurring polymers to treated dentin matrix components. However, the routine use and banking of dental stem cells still holds some major challenges, such as culture-associated differences, patient-related variability and the effects of culture medium additives. Only in-depth evaluation of these problems and the implementation of standardized models and protocols will effectively lead to better alternatives for patients who no longer benefit from current treatment protocols.

http://www.ncbi.nlm.nih.gov/pubmed/25869156/

Abstract

Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by the loss of nigrostriatal dopaminergic (DAergic) neurons and the depletion of striatal dopamine. Here we show that DAergic-neuron-like cells could be efficiently induced from stem cells derived from human exfoliated deciduous teeth (SHEDs), and that these induced cells had therapeutic benefits in a 6-OHDA-induced Parkinsonian rat model. In our protocol, EGF and bFGF signaling activated the SHED's expression of proneural genes, Ngn2 and Mash1, and subsequent treatment with brain-derived neurotrophic factor (BDNF) promoted their maturation into DAergic neuron-like SHEDs (dSHEDs). A hypoxic DAergic differentiation protocol improved cell viability and enhanced the expression of multiple neurotrophic factors, including BDNF, GDNF, NT-3, and HGF. Engrafted dSHEDs survived in the striatum of Parkinsonian rats, improved the DA level more efficiently than engrafted undifferentiated SHEDs, and promoted the recovery from neurological deficits. Our findings further suggested that paracrine effects of dSHEDs contributed to neuroprotection against 6-OHDA-induced neurodegeneration and to nigrostriatal tract restoration. In addition, we found that the conditioned medium derived from dSHEDs protected primary neurons against 6-OHDA toxicity and accelerated neurite outgrowth in vitro. Thus, our data suggest that stem cells derived from dental pulp may have therapeutic benefits for PD.

http://www.ncbi.nlm.nih.gov/pubmed/25863132/

Abstract

BACKGROUND:

Human dental pulp represents a suitable alternative source of stem cells for the purpose of cell-based therapies in regenerative medicine, because it is relatively easy to obtain it, using low invasive procedures. This study characterized and compared two subpopulations of adult stem cells derived from human dental pulp (hDPSCs). Human DPSCs, formerly immune-selected for STRO-1 and c-Kit, were separated for negativity and positivity to CD34 expression respectively, and evaluated for cell proliferation, stemness maintenance, cell senescence and multipotency.

RESULTS:

The STRO-1(+)/c-Kit(+)/CD34(+) hDPSCs showed a slower proliferation, gradual loss of stemness, early cell senescence and apoptosis, compared to STRO-1(+)/c-Kit(+)/CD34(-) hDPSCs. Both the subpopulations demonstrated similar abilities to differentiate towards mesoderm lineages, whereas a significant difference was observed after the neurogenic induction, with a greater commitment of STRO-1(+)/c-Kit(+)/CD34(+) hDPSCs. Moreover, undifferentiated STRO-1(+)/c-Kit(+)/CD34(-) hDPSCs did not show any expression of CD271 and nestin, typical neural markers, while STRO-1(+)/c-Kit(+)/CD34(+) hDPSCs expressed both.

CONCLUSIONS:

These results suggest that STRO-1(+)/c-Kit(+)/CD34(-) hDPSCs and STRO-1(+)/c-Kit(+)/CD34(+) hDPSCs might represent two distinct stem cell populations, with different properties. These results trigger further analyses to deeply investigate the hypothesis that more than a single stem cell population resides within the dental pulp, to better define the flexibility of application of hDPSCs in regenerative medicine.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4377026/pdf/12861_2015_Artic... /

Abstract

Tissue engineering is an emerging field of science that focuses on creating suitable conditions for the regeneration of tissues. The basic components for tissue engineering involve an interactive triad of scaffolds, signaling molecules, and cells. In this context, stem cells (SCs) present the characteristics of self-renewal and differentiation capacity, which make them promising candidates for tissue engineering. Although they present some common markers, such as cluster of differentiation (CD)105, CD146 and STRO-1, SCs derived from various tissues have different patterns in relation to proliferation, clonogenicity, and differentiation abilities in vitro and in vivo. Tooth-derived tissues have been proposed as an accessible source to obtain SCs with limited morbidity, and various tooth-derived SCs (TDSCs) have been isolated and characterized, such as dental pulp SCs, SCs from human exfoliated deciduous teeth, periodontal ligament SCs, dental follicle progenitor cells, SCs from apical papilla, and periodontal ligament of deciduous teeth SCs. However, heterogeneity among these populations has been observed, and the best method to select the most appropriate TDSCs for regeneration approaches has not yet been established. The objective of this review is to outline the current knowledge concerning the various types of TDSCs, and discuss the perspectives for their use in regenerative approaches.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4369495/pdf/WJSC-7-399.pdf /

Abstract

Our aim is to investigate the cytobiological effects of autologous platelet-rich fibrin (PRF) on dental pulp stem cells (DPSCs) and to explore the ectopic and orthotopic possibilities of dental pulp revascularization and pulp-dentin complex regeneration along the root canal cavities of the tooth by using a novel tissue-engineered transplant composed of cell-sheet fragments of DPSCs and PRF granules. Canine DPSCs were isolated and characterized by assaying their colony-forming ability and by determining their cell surface markers and osteogenic/adipogenic differentiation potential. The biological effects of autologous PRF on DPSCs, including cell proliferation, alkaline phosphatase (ALP) activity and odonto-/osteogenic gene expression, were then investigated and quantified. A novel transplant consisting of cell-sheet fragments of DPSCs and PRF granules was adopted to regenerate pulp-dentin-like tissues in the root canal, both subcutaneously in nude mice and in the roots of canines. PRF promoted the proliferation of DPSCs in a dose- and time-dependent manner and induced the differentiation of DPSCs to odonto-/osteoblastic fates by increasing the expression of the Alp, Dspp, Dmp1 and Bsp genes. Transplantation of the DPSC/PRF construct led both to a favorable regeneration of homogeneous and compact pulp-like tissues with abundantly distributed blood capillaries and to the deposition of regenerated dentin along the intracanal walls at 8 weeks post-operation. Thus, the application of DPSC/PRF tissue constructs might serve as a potential therapy in regenerative endodontics for pulp revitalization or revascularization.

http://www.ncbi.nlm.nih.gov/pubmed/25797716/

Abstract

Corneal blindness afflicts millions of individuals worldwide and is currently treated by grafting with cadaveric tissues; however, there are worldwide donor tissue shortages, and many allogeneic grafts are eventually rejected. Autologous stem cells present a prospect for personalized regenerative medicine and an alternative to cadaveric tissue grafts. Dental pulp contains a population of adult stem cells and, similar to corneal stroma, develops embryonically from the cranial neural crest. We report that adult dental pulp cells (DPCs) isolated from third molars have the capability to differentiate into keratocytes, cells of the corneal stoma. After inducing differentiation in vitro, DPCs expressed molecules characteristic of keratocytes, keratocan, and keratan sulfate proteoglycans at both the gene and the protein levels. DPCs cultured on aligned nanofiber substrates generated tissue-engineered, corneal stromal-like constructs, recapitulating the tightly packed, aligned, parallel fibrillar collagen of native stromal tissue. After injection in vivo into mouse corneal stroma, human DPCs produced corneal stromal extracellular matrix containing human type I collagen and keratocan and did not affect corneal transparency or induce immunological rejection. These findings demonstrate a potential for the clinical application of DPCs in cellular or tissue engineering therapies for corneal stromal blindness.

http://www.ncbi.nlm.nih.gov/pubmed/25713466/

Abstract

This study was focused on the isolation and characterization of mesenchymal stem cells (MSCs) from human dental pulp (DPSC). Methods The study was performed in the Department for Oral and Cranio-Maxillo- Facial Surgey Hamad Medical Corporation, Doha, Qatar and Weill Cornell Medical Colleague Doha, Qatar, in period 2010-2011. Dental pulp was extracted from premolars and third molars of 19 healthy patients. The pulp was digested in a solution of 3 mg/mL collagenase type I and 4 mg/mL dispase for 1 hour at 37C. After filtration, cells were cultured in Dulbecco's Modified Eagle Medium (DMEM Low Glucoses) with 20% Fetal Bovine Serum (FBS), 2mM L-glutamine and antibiotics (100 U/mL penicillin, 100 ug/mL streptomycin) at 37 °C under 5% CO2. Cultures were treated with osteoinductive medium for differentiation MSC in to the osteoblast cell line. Staining with Alizarin red were used for the detection of the osteoblast production and calcification new formed tissue. Results On the total of three out of 19 patients it was possible to isolate DPMSCs after 2 to 3 weeks: in one patient it was not possible to expand MSCs because of infection, and in other two patients positive Alizarin red staining reaction showed osteogenic differentiation capability and strong mineralization in vitro. Conclusion The main advantage of using DPSC is absence of morbidity. MSCs could be isolated noninvasively from teeth, routinely extracted in the clinic and discarded as medical waste. Standardization of clinical and laboratory protocols for DPMSCs isolation and team work coordination could lead to significantly improved result.

http://www.ncbi.nlm.nih.gov/pubmed/25669333 /

Abstract

Recently, numerous types of human dental tissue-derived mesenchymal stem cells (MSCs) have been isolated and characterized, including dental pulp stem cells, stem cells from exfoliated deciduous teeth, periodontal ligament stem cells, dental follicle progenitor cells, alveolar bone-derived MSCs, stem cells from apical papilla, tooth germ progenitor cells, and gingival MSCs. All these MSC-like cells exhibit self-renewal, multilineage differentiation potential, and immunomodulatory properties. Several studies have demonstrated the potential advantages of dental stem cell-based approaches for regenerative treatments and immunotherapies. This review outlines the properties of various dental MSC-like populations and the progress toward their use in regenerative therapy. Several dental stem cell banks worldwide are also introduced, with a view toward future clinical application.

http://onlinelibrary.wiley.com/doi/10.1002/stem.1909/full /

Abstract

Human dental pulp stem cells (hDPSCs) hold great promise as a source of adult stem cells for utilization in regenerative medicine. Successful storage and post thaw recovery of DPSCs without loss of function is a key issue for future clinical application. Most of the cryopreservation methods use controlled rate freezing and vapor phase nitrogen to store stem cells. But these methods are both expensive and laborious. In this study, we isolated DPSCs from a patient undergoing impacted mandibular third molar extraction. We adopted eight different methods of cryopreservation at -80 °C for long term storage of the DPSC aliquots. Various parameters like proliferation, cell death, cell cycle, retention of stemness markers and differentiation potential were studied post cryopreservation period of 1 year. We observed successful recovery of stem cells in every method and a significant difference in proliferation potential and cell death between samples stored by different methods. However, post thaw, all cells retained their stemness markers. All DPSCs stored by different methods were able to differentiate into osteoblast like cells, adipocytes and neural cells. Based on these parameters we concluded that uncontrolled freezing at a temperature of -80 °C is as effective as controlled freezing using ethanol vessels and other cryopreservation methods. To the best of our knowledge, our study provides the first proof of concept that long term storage in uncontrolled freezing of cells at -80 °C in 10 % DMSO does not affect the revival capacity of hDPSCs. This implies that DPSCs may be used successfully for tissue engineering and cell based therapeutics even after long term, uncontrolled cryopreservation.

http://www.ncbi.nlm.nih.gov/pubmed/25663639/

Abstract

The loss of retinal ganglion cells (RGCs) in majority of retinal degenerative diseases is the first seen pathological event. A lot of studies aim to discover suitable cell sources to replace lost and damaged RGCs. Among them dental pulp stem cells (DPSCs) have a great potential of differentiating into neuronal lineages as well as RGCs. Moreover, three-dimensional (3D) networks and its distribution for growing and differentiation of stem cells as much as possible mimic to native tissue holds great potential in retinal tissue engineering. In this study, we isolate DPSCs from rat incisors and validate them with flow cytometry. Briefly, we differentiated cells using DMEM/F12 containing FGF2, Shh and 0.5% FBS into retinal ganglion-like cells (RGLCs) in two conditions; 3D state in biocompatible fibrin hydrogel and two-dimensional (2D) or conventional culture in polystyrene plates. Immuncytochemical and gene expression analysis revealed the expression of Pax6, Atoh7 and BRN3B increased in 3D fibrin culture compared to 2D conventional culture. In combination, these data demonstrate that using 3D networks can resemble near natural tissue properties for effective generating RGCs which used to treat neurodegenerative diseases such as glaucoma.

http://www.ncbi.nlm.nih.gov/pubmed/25543058/

Abstract

The current definitive treatment for acute or chronic liver condition, that is, cirrhosis, is liver transplantation from a limited number of donors, which might cause complications after donation. Hence, bone marrow stem cell transplantation has been developed, but the risk of carcinogenesis remains. We have recently developed a protocol for hepatic differentiation of CD117(+) stem cells from human exfoliated deciduous teeth (SHED). In the present study, we examine whether SHED hepatically differentiated (hd) in vitro could be used to treat acute liver injury (ALI) and secondary biliary cirrhosis. The CD117(+) cell fraction was magnetically separated from SHED and then differentiated into hepatocyte-like cells in vitro. Thecells were transplanted into rats with either ALI or induced secondary biliary cirrhosis. Engraftment of human liver cells was determined immunohistochemically and by in situ hybridization. Recovery of liver function was examined by means of histochemical and serological tests. Livers of transplanted animals were strongly positive for human immunohistochemical factors, and in situ hybridization confirmed engraftment of human hepatocytes. The tests for recovery of liver function confirmed the presence of human hepatic markers in the animals' blood serum and lack of fibrosis and functional integration of transplanted human cells into livers. No evidence of malignancy was found. We show that in vitro hdSHED engraft morphologically and functionally into the livers of rats having acute injury or secondary biliary cirrhosis. SHED are readily accessible adultstem cells, capable of proliferating in large numbers before differentiating in vitro. This makes SHED an appropriate and safe stem cell source for regenerative medicine.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4333255/pdf/ten.tea.2014.016...

Abstract

To investigate the behaviour of dental pulp cells under hypoxic conditions in vivo using an experimental animal model.

METHODOLOGY:

A mini-screw was inserted into the inferior dental nerve canal of rats to arrest the blood supply, which resulted in a reduced oxygen level in the dental pulps of molar teeth used for the experimental group. The decrease in blood supply was evaluated by injected India ink in transparent specimens. The hypoxia marker hypoxyprobe-1 was investigated by immunohistochemical staining. The mRNA expressions of ATP-binding cassette transporter (ABC) G2 (ABCG2) which is a marker for the capacity to excrete metabolites and for stem-like cells as well as dentine sialophosphoprotein (DSPP) and osteocalcin (OCN) which are markers for mineralization were evaluated by RT-PCR. Protein was evaluated by immunohistochemical staining using ABCG2, dentine sialoprotein (DSP) and OCN.

RESULTS:

The evaluation of India ink indicated a decreased blood supply in the transparent specimens, and hypoxyprobe-1 immunohistochemical staining showed positive expression. ABCG2, DSPP and OCN mRNA expressions increased at 7 and 14 days. Immunohistochemically, ABCG2, DSP and OCN-positive cells were localized in the odontoblastic layer.

CONCLUSIONS:

Hypoxic conditions promoted mineralization and differentiation of dental pulp cells of the odontoblastic layer.

http://www.ncbi.nlm.nih.gov/pubmed/24661255 /

Abstract

Regenerative medicine is an emerging field of biotechnology that combines various aspects of medicine, cell and molecular biology, materials science and bioengineering in order to regenerate, repair or replace tissues. The oral surgery and maxillofacial surgery have a role in the treatment of traumatic or degenerative diseases that lead to a tissue loss: frequently, to rehabilitate these minuses, you should use techniques that have been improved over time. Since 1990, we started with the use of growth factors and platelet concentrates in oral and maxillofacial surgery; in the following period we start to use biomaterials, as well as several type of scaffolds and autologous tissues. The frontier of regenerative medicine nowadays is represented by the mesenchymal stem cells (MSCs): overcoming the ethical problems thanks to the use of mesenchymal stem cells from adult patient, and with the increasingly sophisticated technology to support their manipulation, MSCs are undoubtedly the future of medicine regenerative and they are showing perspectives unimaginable just a few years ago. Most recent studies are aimed to tissues regeneration using MSCs taken from sites that are even more accessible and rich in stem cells: the oral cavity turned out to be an important source of MSCs with the advantage to be easily accessible to the surgeon, thus avoiding to increase the morbidity of the patient. The future is the regeneration of whole organs or biological systems consisting of many different tissues, starting from an initial stem cell line, perhaps using innovative scaffolds together with the nano-engineering of biological tissues.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4278878/pdf/ijmsv12p0072.pdf/

Abstract

PURPOSE:

This study aims to propose the dental pulp stem cells (DPSCs) as a model for studying two features related to neurofibromatosis type 1 (NF1), i.e. augmented proliferative capacity and altered osteogenic differentiation.

METHODS:

We isolated a DPSC from the pulp of deciduous teeth of a 6-year-old NF1 patient and two other healthy children of similar age. Cell proliferation was assayed by counting with a haemocytometer after successive cell re-plating. In order to compare osteogenic differentiation, we used osteoblast-differentiating medium and quantified alizarin stain, which relates to degree of calcification, and evaluated the expression of osteoblastic markers by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS:

The DPSCs isolated from the NF1 patient displayed a greater rate of proliferation when compared to the control cells. Osteogenic differentiation occurred as expected for both NF1 and control, which concerned cell morphology and expression of osteoblast marker genes ALP, BMP2, BMP4, OCN and SPP1. However, alizarin staining denoted a markedly lower calcification level in the cells from the NF1-diagnosed child, considering that less calcium deposits were visualized under light microscopy and a smaller amount of alizarin could be quantified by spectrophotometry after extraction from the stained cells.

CONCLUSION:

DPSCs seem to be useful as a model for studying NF1 and predicting prognosis of patients, since their in vitro behaviour seems to mimic at least two features of this disorder: higher tendency to develop bone abnormalities and neoplastic cell proliferation.

http://www.ncbi.nlm.nih.gov/pubmed/25480698/

Abstract

Although the primary cell cultures from dental pulp and other oral tissue are frequently used to study osteogenic potential and stem cell responses, few systematic and comparative studies on stemness for the dentinogenic differentiation of these cells have been conducted. In the present study, to investigate the stemness of oral primary cells during extended culture, human adult dental pulp cells (hDPCs), periodontal ligament stem cells(hPDLSCs) and gingival fibroblasts (hGFs) were obtained and cultured from pulp tissue, periodontal ligaments, and marginal and attached gingival tissue of extracted third molars, respectively. As shown by fluorescence-activated cell sorting analysis and immunophenotyping, the mesenchymalstem cell markers, CD44, CD73, CD90, CD146 and CD166, were highly expressed in early passage hDPCs, hPDLSCs and hGFs. However, when the cells were treated with osteogenic additives, mineralization markedly increased in the hDPCs and hPDLSCs, but not in the hGFs. Moreover, the expression of dentinogenic markers, such as dentin sialophosphoprotein and dentin matrix protein-1, appeared to decrease during extended culture past passage number 8 of the hDPCs and hPDLSCs. These data suggest that hDPCs and hPDLSCs may have differentiation potential during the early passages, and that their progenitor potential is diminished during extended culture. The hGFs did not show differentiation capability during culture, even though they contained general mesenchymal stem cell surface proteins. The transcriptional expression of dentinogenic markers in hDPCs was not affected by co-culture with hPDLSCs and/or hGFs.

http://www.ncbi.nlm.nih.gov/pubmed/25355399/

Abstract

Melatonin's effect on hepatic differentiation of stem cells remains unclear. The aim of this study was to investigate the action of melatonin on hepatic differentiation as well as its related signaling pathways of human dental pulp stem cells (hDPSCs) and to examine the therapeutic effects of a combination of melatonin and hDPSC transplantation on carbon tetrachloride (CCl4 )-induced liver fibrosis in mice. In vitro hepatic differentiation was assessed by periodic acid-Schiff (PAS) staining and mRNA expression for hepatocyte markers. Liver fibrosis model was established by injecting 0.5 mL/kg CCl4 followed by treatment with melatonin (5 mg/kg, twice a week) and hDPSCs. In vivo therapeutic effects were evaluated by histopathology and by means of liver function tests including measurement of alanine transaminase (ALT), aspartate transaminase (AST), and ammonia levels. Melatonin promoted hepatic differentiation based on mRNA expression of differentiation markers and PAS-stained glycogen-ladencells. In addition, melatonin increased bone morphogenic protein (BMP)-2 expression and Smad1/5/8 phosphorylation, which was blocked by the BMP antagonist noggin. Furthermore, melatonin activated p38, extracellular signal-regulated kinase (ERK), and nuclear factor-κB (NF-κB) in hDPSCs. Melatonin-induced hepatic differentiation was attenuated by inhibitors of BMP, p38, ERK, and NF-κB. Compared to treatment of CCl4 -injured mice with either melatonin or hDPSC transplantation alone, the combination of melatonin and hDPSC significantly suppressed liver fibrosis and restored ALT, AST, and ammonia levels. For the first time, this study demonstrates that melatonin promotes hepatic differentiation of hDPSCs by modulating the BMP, p38, ERK, and NF-κB pathway. Combined treatment of grafted hDPSCs and melatonin could be a viable approach for the treatment of liver cirrhosis.

http://onlinelibrary.wiley.com/doi/10.1111/jpi.12198/full/