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Abstract Objective: To investigate the regeneration of rat's salivary gland diabetic defect after intraglandular transplantation of Human Dental Pulp Stem Cells (HDPSCs) on acinar cell vacuolization and Interleukin-10 (IL-10). Material and Methods: HDPSCs isolated from the dental pulp of first premolars #34. HDPSCs from the 3rd passage was characterized by immunocytochemistry of CD73, CD90, CD105 and CD45. Twenty-four male Wistar rats, 3-month-old, 250-300 grams induced with Streptozotocin 30 mg/kg body weight to create diabetes mellitus (DM) divided into 4 groups (n=6); positive control group on Day-7; positive control group on Day-14; treatment group Day-7 (DM+5.105HDPSCs); treatment group on Day-14. On Day-7 and Day-14, rats were sacrificed. Histopathological examination performed to analyze acinar cells vacuolization while Enzyme-linked Immunoabsorbent Assay to measure IL-10 serum level. Data obtained were analyzed statistically using multiple comparisons Bonferroni test, Kruskal Wallis, Shapiro-Wilk and Levene's test result Results: The highest acinar cell vacuolization found in control group Day 14 (0.239 ± 0.132), meanwhile the lowest acinar cell vacuolization found in treatment group Day 7 (0.019 ± 0.035) with significant difference (p=0.003). The highest IL-10 serum level found in treatment group Day 14 (175.583 ± 120.075) with significant difference (p=0.001) Conclusion: Transplantation of HDPSC was able to regenerate submandibular salivary gland defects in diabetic rats by decreasing acinar cell vacuolization and slightly increase IL-10 serum level.

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Introducción: los avances en el conocimiento de la biología de las células madre y los mecanismos moleculares que regulan la autorrenovación y diferenciación celular posibilitan la aparición de nuevas opciones terapéuticas para diversas enfermedades que, hasta el momento, no tienen tratamientos efectivos. Objetivo: exponer en forma estructurada información referente a las células madre, embrionarias y adultas, sus fuentes de obtención, potencialidades, versatilidad y mecanismos de acción. Método: se revisó la literatura nacional e internacional sobre el tema, publicada básicamente entre los años 2011 y 2015 en español e inglés, en formatos impreso y digital. La búsqueda en Internet abarcó las bases de datos Medline, CUMED y SciELO Cuba. Como criterios de búsqueda se emplearon células madre, células troncales, células pluripotenciales, medicina regenerativa e ingeniería de tejidos. A partir de los materiales seleccionados se elaboró una reseña estructurada. Desarrollo: las células madre tienen la capacidad de autorreplicarse indefinidamente por división celular (autorrenovación) y en condiciones microambientales adecuadas pueden diferenciarse, morfológica y funcionalmente, en otros tipos de células especializadas. Diversas investigaciones en modelos animales y observaciones en humanos muestran que las células madre adultas pueden contribuir a la regeneración de tejidos dañados. Conclusiones: las propiedades exclusivas de las células madre y su comportamiento biológico abren perspectivas alentadoras en las investigaciones básicas y clínicas con vistas a su empleo terapéutico en diversas enfermedades. No obstante, es preciso ahondar más en los mecanismos de renovación, diferenciación y acción de las células madre, consensuar resultados investigativos y establecer recomendaciones clínicas basadas en las evidencias científicas(AU)

Introduction: advances in the knowledge of stem cell biology and the molecular mechanisms that regulate self-renovation and cellular differentiation allow the emergence of new therapeutic options for various diseases that, so far, do not have effective treatments. Objective: to collect in a structured form information regarding stem cells, embryonic and adult, their sources of production, potentialities, versatility and mechanisms of action. Method: the national and international literature on the subject, published mainly between 2011 and 2015 in Spanish and English, in print and digital formats was reviewed. The Internet search included the Medline, CUMED and SciELO Cuba databases; Stem cells, pluripotential cells, regenerative medicine and tissue engineering were used as search criteria. A structured review was prepared from the selected materials.Development: stem cells have the ability to self-replicate indefinitely by cell division (self-renewal) and under appropriate microenvironmental conditions can morphologically and functionally differentiate into other specialized cell types. Various investigations in animal models and observations in humans show that adult stem cells can contribute to the regeneration of damaged tissues.Conclusions: the exclusive properties of stem cells and their biological behavior open up promising perspectives in basic and clinical research with a view to their therapeutic use in various diseases. However, there is a need to delve deeper into the mechanisms of stem cell renewal, differentiation and action, to agree on research results and to establish clinical recommendations based on scientific evidence(AU)

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La utilización de células indiferenciadas embrionarias y de células diferenciadas inducidas para que se comporten como las anteriores permite dar origen adiferentes tejidos que pueden ser usados en medicina reconstructiva en reemplazo de los deteriorados...

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Este artículo fue escrito para honrar a J.B Gurdon y S. Yamanaka, laureados con el Premio Nobel en Fisiología p Medicina 2012 "por el descubrimiento de que las células maduras pueden ser reprogramadas para volverse pluripotentes". Se presentan en forma concisa sus aportes científicos y reseñas biográficas. J.B. Gardon, en Inglaterra, demostró hace 50 años en anfibios que al trasplantar el núcleo de una célula intestinal a un huevo u ovocito enuncleado se obtiene una célula totipotente que se convierte en un embrión y se desarrolla hasta convertirse en una rana adulta, lo cual implica la conservación de genoma en el proceso de diferenciación y la resersibilidad de dicho proceso. Estos descubrimientos llevaron a que otros autores realizaran la clonación de mamiferos utilizando el núcleo de células somáticas y la obtención de células madre pluripotentes a partir de los embrines que se producen in vitro por el desarrollo de las células totipotentes. Se mencionan varias aplicaciones y las contribuciones de Gurdon para comprender el proceso de reprogramación. S. Yamanaka, en Japón, hace seis años, reprogramó al estado embrionario fibroblastos cutáneos de ratones y humanos adultos insertando mediante vectores retrovirales una combinación de los genes de cuatro factores de transcripción: Oct3/4, Sox2, Klf4 y c-Myc. Las células reprogramadas fueron denominadas células madre pluripotentes inducidas. Utilizando la técnica desarrollada por Yamanaka y otras surgidas a raiz de sus descrubrimientos, miles de personas obtienen ahora células madre pluripotentes inducidas a partir de muchas especies y tejidos, incluyendo seres humanos sanos y enfermos. Las células madre pluripotentes o sus derivadas tienen un amplio potencial de aplicación, entre ellas, estudios de embriología y fisiopatología, modelos de enfermedades, descubrimiento de drogas y terapias celulares

This paper was written to honor J.B Gurdon y S. Yamanaka, 2012 Nobel Prize laureates in Physiology or Medicine for "the discovery that mature cells can be reprogrammed to become pluripotent". Their main scientific contributions and biography are presented in a concise manner. JB Gurdon, in England, showed fifty years ago in amphibians that the transplantation of the nucleus of an intestinal cell to an enucleated egg or oocyte produces a totipotent cell that develops into an embryo and adult frog. This implies that cellular differentiation is reversible and the genome is conserved in that process. The discoveries led to the cloning of mammals by other authors using the nucleus of somatic cells and to obtain pluripotent stem cells in vitro from the embryos produced by development of the totipotent cells. Some applications are considered. Gurdon's contribution to the understanding of the reprogramming process is mentioned. S. Yamanaka six years ago in Japan reprogrammed skin fibroblastis from adult mice and humans to the embryonic state by introducing via retroviral vectors a combination of the genes of 4 transcription factors, Oct3/4. Sox2, Klf4 and c-Myc. The reprogammed cells were named induced pluripontent stem cells. Throusands of people are now producing induced pluripotent stem cells from many tissues and species, including healthy and ill humans, using Yamanaka's methods and other techniques stimulated by his work. Pluripotent stem cells or their derivatives have great potential for a wide range of applications including research in embryology and pathophysiology, disease modeling, drug discovery and cell transplantation therapies

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UNLABELLED: The direct induction of adventitious buds and somatic embryos from explants is a morphogenetic process that is under the influence of exogenous plant growth regulators and its interactions with endogenous phytohormones. We performed an in vitro histological analysis in peach palm (Bactris gasipaes Kunth) shoot apexes and determined that the positioning of competent cells and their interaction with neighboring cells, under the influence of combinations of exogenously applied growth regulators (NAA/BAP and NAA/TDZ), allows the pre-procambial cells (PPCs) to act in different morphogenic pathways to establish niche competent cells. It is likely that there has been a habituation phenomenon during the regeneration and development of the microplants. This includes promoting the tillering of primary or secondary buds due to culturing in the absence of NAA/BAP or NAA/TDZ after a period in the presence of these growth regulators. Histological analyses determined that the adventitious roots were derived from the dedifferentiation of the parenchymal cells located in the basal region of the adventitious buds, with the establishment of rooting pole, due to an auxin gradient. Furthermore, histological and histochemical analyses allowed us to characterize how the PPCs provide niches for multipotent, pluripotent and totipotent stem-like cells for vascular differentiation, organogenesis and somatic embryogenesis in the peach palm. The histological and histochemical analyses also allowed us to detect the unicellular or multicellular origin of somatic embryogenesis. Therefore, our results indicate that the use of growth regulators in microplants can lead to habituation and to different morphogenic pathways leading to potential niche establishment, depending on the positioning of the competent cells and their interaction with neighboring cells. KEY MESSAGE: Our results indicate that the use of growth regulators in microplants can lead to habituation and to different morphogenic pathways leading to potential niche establishment, depending on the positioning of the competent cells and their interaction with neighboring cells.

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Stem cells can be classified as embryonic stem (ES) cells or adult stem cells considering their origin. If plasticity is considered, stem cells can be classified as totipotent, when stem cells retain the ability to give rise to an entire new organism. When stem cells lose this capacity, cells are named pluripotent stem cells, which can give rise to almost all mature cell types that compound an organism. Totipotent and pluripotent stem cells can be obtained from developing early-stage embryos. Multipotent is the group of adult stem cells with restricted plasticity. These cells can differentiate into a defined cell type related with a specific organ or tissue. ES cells can be propagated in vitro under undifferentiated system or with a series of protocols to induce cell differentiation. On the other hand, multipotent adult stem cells cannot be maintained in vitro in an undifferentiated form, except for a special class of adherent adult stem cells named mesenchimal stem cells, which can be expanded in vitro conserving their undifferentiated characteristics. Considering the ability to generate teratomas, ES cells were not used in experimental in vivo cell transplant. On the other hand, several experimental adult stem cells transplants have been performed with controversial results

Considerando a origem de obtenção, as células-tronco podem ser classificadas como células-tronco embrionárias (ES) ou como células-tronco adultas. Mas, se a plasticidade for considerada, as células-tronco podem ser classificadas como células totipotentes, quando as células-tronco preservam a capacidade de dar origem a um novo indivíduo completo. Quando as células-tronco perdem esta capacidade, passam a ser classificadas como células-tronco pluripotentes, que podem dar origem a praticamente todos os tipos celulares maduros que compõem um organismo. Células-tronco totipotentes e pluripotentes podem ser obtidas de estágios embrionários iniciais. O grupo de células-tronco que apresenta plasticidade restrita é denominado de multipotente. Estas células podem se diferenciar em determinado tipo celular comprometido com um órgão ou tecido específico. Células ES podem ser expandidas in vitro, mantendo sua forma indiferenciada, ou podem ser submetidas a uma série de protocolos, que irão induzir diferenciação in vitro. Por outro lado, as células-tronco adultas multipotentes não podem ser mantidas in vitro na forma indiferenciada, exceto uma subpopulação de célulastronco adultas aderentes, denominadas células-tronco mesenquimais, que podem ser mantidas in vitro na forma indiferenciada. Considerando a capacidade de gerar teratomas, as células ES não foram utilizadas para transplante celular experimental in vivo. Além disso, várias cirurgias de transplantes experimentais com células-tronco adultas têm sido realizadas, porém apresentando resultados controversos

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Os autores apresentam nesse artigo uma revisão atualizada sobre aplicação clínica dos resultados obtidos nas pesquisas sobre as células-tronco. O principal objetivo é o esclarecimento a respeito da capacidade de diferenciação dessas células, bem como do potencial de utilização das mesmas na prática médica, tendo em vista o futuro promissor de uma nova linha de raciocínio terapêutico: a medicina regenerativa

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Plant cell and tissue culture in a simple fashion refers to techniques which utilize either single plant cells, groups of unorganized cells (callus) or organized tissues or organs put in culture, under controlled sterile conditions.

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