Artículos Científicos 2017

Stem Cells from Dental Pulp: What Epigenetics Can Do with Your Tooth. Rodas-Junco BA, Canul-Chan M, Rojas-Herrera RA, De-la-Peña C, Nic-Can GI. Front Physiol. 2017 Dec 6;8:999

Abstract

Adult stem cells have attracted scientific attention because they are able to self-renew and differentiate into several specialized cell types. In this context, human dental tissue-derived mesenchymal stem cells (hDT-MSCs) have emerged as a possible solution for repairing or regenerating damaged tissues. These cells can be isolated from primary teeth that are naturally replaced, third molars, or other dental tissues and exhibit self-renewal, a high proliferative rate and a great multilineage potential. However, the cellular and molecular mechanisms that determine lineage specification are still largely unknown. It is known that a change in cell fate requires the deletion of existing transcriptional programs, followed by the establishment of a new developmental program to give rise to a new cell lineage. Increasing evidence indicates that chromatin structure conformation can influence cell fate. In this way, reversible chemical modifications at the DNA or histone level, and combinations thereof can activate or inactivate cell-type-specific gene sequences, giving rise to an alternative cell fates. On the other hand, miRNAs are starting to emerge as a possible player in establishing particular somatic lineages. In this review, we discuss two new and promising research fields in medicine and biology, epigenetics and stem cells, by summarizing the properties of hDT-MSCs and highlighting the recent findings on epigenetic contributions to the regulation of cellular differentiation.

https://www.ncbi.nlm.nih.gov/pubmed/29270128

How has dental pulp stem cells isolation been conducted? A scoping review Ferrúa CP, Centeno EGZ, Rosa LCD, Amaral CCD, Severo RF, Sarkis-Onofre R, Nascimento GG, Cordenonzi G, Bast RK, Demarco FF, Nedel F. Braz Oral Res. 2017 Dec 18;31:

Abstract

The objective of this study was to realize a scoping review the literature in order to identify the profile of DPSCs isolation and analyze the possible risk factors that could change the native behavior of these cells. An initial search was conducted using the following MeSH terms: "(dental pulp stem cell [MeSH])"; "(dental pulp [MeSH])" AND "(stem cell [MeSH])"; "("dental pulp stem cell" [MeSH]")". The electronic search was done without date restriction up to and including April 2014, in PubMed, Scopus, Scielo and ISI Web of Knowledge databases. Studies were submitted to inclusion and exclusion criteria and 222 articles were included. Data showed that over the past 15 years many studies have been conducted using DPSCs. However this is the first systematic review regarding the isolation of stem cell, and more specifically of dental pulp stem cells. The isolation of dental pulp stem cells showed great variability, hampering the development of standard protocols to achieve in vitro dental pulp stem cells with similar characteristics. This scoping review combined, for the first time, the methodologies used for dental pulp stem isolation, highlighting the most frequently used.

https://www.ncbi.nlm.nih.gov/pubmed/29267658

The Differentiation Potential of Human Natal Dental Pulp Stem Cells into Insulin-Producing Cells Suchanek J, Nasry SA, Soukup T. Folia Biol (Praha). 2017;63(4):132-138.

Abstract

Mesenchymal stem cells have the ability to differentiate into insulin-producing cells, raising the hope for diabetes mellitus treatment. The aim of this research was to study the ability of stem cells from discarded natal teeth to differentiate into insulinproducing cells. Two vital human natal teeth were obtained from a healthy 2-day-old female. Stem cells from the dental pulp were isolated, cultured under xenogenic-free conditions, propagated and characterized. Proliferative activity, population doubling time and viability were measured, and the multipotent differentiation ability was investigated. A twostep protocol was used to induce the human natal dental pulp stem cells to differentiate into insulinproducing cells. Phenotypic analysis was done using flow cytometry. Immunohistochemistry was performed to detect insulin and C-peptide. PDX1, HES1 and Glut2 gene expression analysis was performed by quantitative reverse transcription-polymerase chain reaction. Human natal dental pulp stem cells were able to undergo osteogenic, chondrogenic and adipogenic differentiation upon exposure to the specific differentiation media for each lineage. Their differentiation into insulin-producing cells was confirmed by expression of C-peptide and insulin, as well as by 975.4 % higher expression of PDX-1 and 469.5 % higher expression of HES1 in comparison to the cells cultivated in standard cultivation media. Glut2 transporter mRNA was absent in the non-differentiated cells, and differentiation of the stem cells into insulin-producing cells induced appearance of the mRNA of this transporter. We were the first to demonstrate that stem cells obtained from the pulp of natal teeth could be differentiated into insulinproducing cells, which might prove useful in the stem cell therapy for type 1 diabetes.

https://www.ncbi.nlm.nih.gov/pubmed/29256855

Stem Cells from Cryopreserved Human Dental Pulp Tissues Sequentially Differentiate into Definitive Endoderm and Hepatocyte-Like Cells in vitro Han YJ, Kang YH, Shivakumar SB, Bharti D, Son YB, Choi YH, Park WU, Byun JH, Rho GJ, Park BW¹. Int J Med Sci. 2017 Nov 2;14(13):1418-1429.

Abstract

We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro. Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro, the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro. Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering.

https://www.ncbi.nlm.nih.gov/pubmed/29200956