Search results for "differentiation"
showing 10 items of 1605 documents
The effects of shock wave stimulation of mesenchymal stem cells on proliferation, migration, and differentiation in an injectable gelatin matrix for …
2020
The treatment of a variety of defects in bony sites could benefit from mitogenic stimulation of osteoprogenitor cells, including endogenous bone marrow-derived mesenchymal stem cells (bMSCs), and from provision of such cells with a matrix permissive of their migration, proliferation, and osteogenic differentiation. That such MSC stimulation could result from treatment with noninvasive (extracorporeal) shock waves (ESWs), and the matrix delivered by injection could enable this therapeutic approach to be employed for applications in which preformed scaffolds and growth factor therapy are difficult to deploy. The objectives of the present study were to investigate focused ESWs for their effect…
The stem cell concept in sponges (Porifera): Metazoan traits.
2006
Sponges are considered the oldest living animal group and provide important insights into the earliest evolutionary processes in the Metazoa. This paper reviews the evidence that sponge stem cells have essential roles in cellular specialization, embryogenesis and Bauplan formation. Data indicate that sponge archaeocytes not only represent germ cells but also totipotent stem cells. Marker genes have been identified which are expressed in totipotent stem cells and gemmule cells. Furthermore, genes are described for the three main cell lineages in sponge, which share a common origin from archaeocytes and result in the differentiation of skeletal, epithelial, and contractile cells.
Vascular niche factor PEDF modulates Notch-dependent stemness in the adult subependymal zone.
2009
We sought to address the fundamental question of how stem cell microenvironments can regulate self-renewal. We found that Notch was active in astroglia-like neural stem cells (NSCs), but not in transit-amplifying progenitors of the murine subependymal zone, and that the level of Notch transcriptional activity correlated with self-renewal and multipotency. Moreover, dividing NSCs appeared to balance renewal with commitment via controlled segregation of Notch activity, leading to biased expression of known (Hes1) and previously unknown (Egfr) Notch target genes in daughter cells. Pigment epithelium-derived factor (PEDF) enhanced Notch-dependent transcription in cells with low Notch signaling,…
Cellular physiology of the neonatal rat cerebral cortex.
2003
The early development of the cerebral cortex is characterized by neurogenesis, neuronal migration, cellular differentiation and programmed cell death. Cajal-Retzius cells, developing cortical plate neurons and subplate cells form a transient synaptic circuit which may serve as a template for the formation of cortical layers and columns. These three neuronal cell types show distinct electrophysiological properties and synaptic inputs. Endogenous or exogenous harmful disturbances during this developmental period may lead to the preservation of early cortical circuits, which may act as trigger zones for the initiation of pathophysiological activity.
Heat shock protein 10 and signal transduction: a “capsula eburnea” of carcinogenesis?
2006
To date, little is known either about the physical interactions of heat shock protein 10 (Hsp10) with other proteins within the cell or its involvement in signal transduction pathways. Hsp10 has been considered mainly as a partner of Hsp60 in the Hsp60/10 protein folding machine. Only recently, Hsp10 was reported to interact with proteins involved in deoxyribonucleic acid checkpoint inactivation, termination of M-phase, messenger ribonucleic acid export, import of nuclear proteins, nucleocytoplasmic transport, and pheromone signaling pathways. At the same time, Hsp10 expression can be up-regulated in cancer cells, because it accumulates as the cell transformation progresses. Recent data sug…
A natural-like synthetic small molecule impairs bcr-abl signaling cascades and induces megakaryocyte differentiation in erythroleukemia cells
2013
Over the past years, we synthesized a series of new molecules that are hybrids of spirocyclic ketones as complexity-bearing cores with bi- and ter-phenyls as privileged fragments. Some of these newly-shaped small molecules showed antiproliferative, pro-apoptotic and differentiating activity in leukemia cell lines. In the present study, to investigate more in depth the mechanisms of action of these molecules, the protein expression profiles of K562 cells treated with or without the compounds IND_S1, MEL_T1, IND_S7 and MEL_S3 were analyzed using two-dimensional gel electrophoresis coupled with mass spectrometry. Proteome comparisons revealed several differentially expressed proteins, mainly r…
TGF-β superfamily signaling is essential for tooth and hair morphogenesis and differentiation
2007
Members of the transforming growth factor beta (TGF-beta) superfamily of signaling molecules are involved in the regulation of many developmental processes that involve the interaction between mesenchymal and epithelial tissues. Smad7 is a potent inhibitor of many members of the TGF-beta family, notably TGF-beta and activin. In this study, we show that embryonic overexpression of Smad7 in stratified epithelia using a keratin 5 promoter, results in severe morphogenetic defects in skin and teeth and leads to embryonic and perinatal lethality. To further analyze the functions of Smad7 in epithelial tissues of adult mice, we used an expression system that allowed a controlled overexpression of …
Systems Biology and Stem Cell Pluripotency: Revisiting the Discovery of Induced Pluripotent Stem Cell
2016
Recent breakthroughs in stem cell biology have accelerated research in the area of regenerative medicine. Over the past years, it has become possible to derive patient-specific stem cells which can be used to generate different cell populations for potential cell therapy. Systems biological modeling of stem cell pluripotency and differentiation have largely been based on prior knowledge of signaling pathways, gene regulatory networks, and epigenetic factors. However, there is a great need to extend the complexity of the modeling and to integrate different types of data, which would further improve systems biology and its uses in the field. In this chapter, we first give a general background…
Alternative splicing products of the tenascin gene distinguish rat liver fat storing cells from arterial smooth muscle cells and skin fibroblasts
1992
Abstract Fat storing-(Ito-)cells (FSC) transform into a myofibroblast-like cell type during liver fibrogenesis. A similar development can be observed in cell culture. At the moment, a definite marker to differentiate transformed FSC from smooth muscle cells (SMC) is not available. We recently found that FSC, SMC and skin fibroblasts (SF) synthesize tenascin, a novel matrix protein. As it is reported that various tissues express different tenascin forms by the mechanism of alternative pre-mRNA splicing, we analyzed the tenascin transcripts in these cell types. Total RNA extracted from cultured FSC, SMC and SF, analyzed by Northern blot hybridization, showed a 7.2 kb transcript in FSC, a 8.7 …
Loss of input from the mossy cells blocks maturation of newly generated granule cells.
2007
The objective of this work is to check whether the input from the mossy cells to the inner molecular layer is necessary for the integration and maturation of the newly generated granule cells of the dentate gyrus (DG) in mice, and if after status epilepticus the sprouting of the mossy fibers can substitute for this projection. Newly generated cells were labeled by administration of 5-bromo-deoxyuridine either before or after pilocarpine administration. The neuronal loss in the hippocampus after administration of pilocarpine combined with scopolamine and diazepam seemed restricted to the hilar mossy cells. The maturation of the granule cells was studied using immunohistochemistry for calreti…