Mesenchymal Stem Cells In Terms Research Articles

Osteogenic differentiation of adipose-derived mesenchymal stem cells using 3D-Printed PDLLA/ β-TCP nanocomposite scaffolds

Designing bone scaffolds containing both organic and inorganic composites simulating the architecture of the bone is the most important principle in bone tissue engineering. The objective of this study was to fabricate a composite scaffold containing poly (D, l)-lactide (PDLLA) and β-tricalcium phosphate (β-TCP) as a platform for osteogenic differentiation of adipose-derived mesenchymal stem cells. In this study, PDLLA/β-TCP scaffolds were fabricated using three-dimensional printing (3D) technology through melt excursion technique. The physicomechanical characteristics, including microstructure, mechanical properties, of the customized scaffolds were investigated. Further, the in vitro biological characteristics of manufactured scaffolds were evaluated in conjugation with buccal fat pad derived mesenchymal stem cells in terms of cell attachment, viability, proliferation, and osteogenic differentiation capacity. The 3D printed customized scaffold in this study showed proper pore size, porosity, mechanical strength, material composition, biocompatibility, and osteogenic differentiation capacity. The obtained results converge to reveal the promising features of the nanocomposite 3D printed platform for personalized bone tissue engineering.

Cellular toxicity of silicon carbide nanomaterials as a function of morphology

Silicon carbide has been shown to be biocompatible and is used as a coating material for implanted medical devices to prevent biofilms. Silicon carbide nanomaterials are also promising in cell tracking due to their stable and strong luminescence, but more comprehensive studies of this material on the nanoscale are needed. Here, we studied the toxicity of silicon carbide nanomaterials on human mesenchymal stem cells in terms of metabolism, viability, adhesion, proliferation, migration, oxidative stress, and differentiation ability. We compared two different shapes and found that silicon carbide nanowires are toxic to human mesenchymal stem cells but not to cancer cell lines at the concentration of 0.1 mg/mL. Control silicon carbide nanoparticles were biocompatible to human mesenchymal stem cells at 0.1 mg/mL. We studied the potential mechanistic effect of silicon carbide nanowires on human mesenchymal stem cells’ phenotype, cytokine secretion, and gene expression. These findings suggest that the toxic effect of silicon carbide nanomaterials to human mesenchymal stem cells are dependent on morphology.

Cardiotrophin-1 stimulates the neural differentiation of human umbilical cord blood-derived mesenchymal stem cells and survival of differentiated cells through PI3K/Akt-dependent signaling pathways.

Cardiotrophin-1 (CT1) plays an important role in the differentiation, development, and survival of neural stem cells. In this study, we analyzed its effects on the stimulation of human umbilical cord blood-derived mesenchymal stem cells in terms of their potential to differentiate into neuron-like cells, their survival characteristics, and the molecular mechanisms involved. The treatment of cells with neural induction medium (NIM) and CT1 generated more cells that were neuron-like and produced stronger expression of neural-lineage markers than cells treated with NIM and without CT1. Bcl-2 and Akt phosphorylation (p-Akt) expression levels increased significantly in cells treated with both NIM and CT1. This treatment also effectively blocked cell death following neural induction and decreased Bax, Bak and cleaved-caspase 3 expression compared with cells treated with NIM without CT1. In addition, the inhibition of phosphatidylinositol 3-kinase (PI3K) abrogated p-Akt and Bcl-2 expression. Thus, PI3K/Akt contribute to CT1-stimulated neural differentiation and to the survival of differentiated cells.

Isolation and Characterization of Meniscus Derived Stem Cells from Rabbit as a Possible Treatment for Damaged Meniscus

The successful surgical restoration of damaged meniscus has been a challenge, largely owing to a lack of characterization of meniscus cells and their precursors. Numerous strategies to repair or replace meniscus have achieved only limited success. Several recent studies have shown beneficial effect of mesenchymal stem cells in meniscus repair. The objective of our study was to characterize meniscus derived mesenchymal stem cells in terms of, colony formation, proliferation, multi potency and self-renewal capacity. Mesenchymal stem cells were isolated from menisci, patellar tendon and bone marrow of rabbits. The multi differentiating potential, colony, morphology and proliferation were studied in vitro. The expression of differential markers was studied by immunocytochemistry, qPCR and western blotting. Three groups of cells appeared similar in colony formation and morphology. All of them were found to express high levels of stem cell markers including SSEA-4, Nanog and nucleostemin. High level of collagen II expression was detected in meniscus derived stem cells. Moreover, these cells appeared to have a pronounced tendency to chondrogenic differentiation under specialized culture conditions. Meniscus-derived mesenchymal stem cells (MMSCs) possessed all the necessary criteria of stem cells, including clonogenicity, self-renewal and multipotent differentiation capacity and possessed a tendency to differentiate into chondrocytes. Our results offer new insights into the biology of meniscus cells, and may assist in future strategies to treat damaged meniscus.

Lung fibroblasts share mesenchymal stem cell features which are altered in chronic obstructive pulmonary disease via the overactivation of the Hedgehog signaling pathway.

BackgroundAlteration of functional regenerative properties of parenchymal lung fibroblasts is widely proposed as a pathogenic mechanism for chronic obstructive pulmonary disease (COPD). However, what these functions are and how they are impaired in COPD remain poorly understood. Apart from the role of fibroblasts in producing extracellular matrix, recent studies in organs different from the lung suggest that such cells might contribute to repair processes by acting like mesenchymal stem cells. In addition, several reports sustain that the Hedgehog pathway is altered in COPD patients thus aggravating the disease. Nevertheless, whether this pathway is dysregulated in COPD fibroblasts remains unknown.Objectives and MethodsWe investigated the stem cell features and the expression of Hedgehog components in human lung fibroblasts isolated from histologically-normal parenchymal tissue from 25 patients—8 non-smokers/non-COPD, 8 smokers-non COPD and 9 smokers with COPD—who were undergoing surgery for lung tumor resection.ResultsWe found that lung fibroblasts resemble mesenchymal stem cells in terms of cell surface marker expression, differentiation ability and immunosuppressive potential and that these properties were altered in lung fibroblasts from smokers and even more in COPD patients. Furthermore, we showed that some of these phenotypic changes can be explained by an over activation of the Hedgehog signaling in smoker and COPD fibroblasts.ConclusionsOur study reveals that lung fibroblasts possess mesenchymal stem cell-features which are impaired in COPD via the contribution of an abnormal Hedgehog signaling. These processes should constitute a novel pathomechanism accounting for disease occurrence and progression.

Chitosan and Chitin Hexamers affect expansion and differentiation of mesenchymal stem cells differently

Chitooligosaccharides are of interest as potential drugs due to their bioactivity and water solubility. We compared the effect of acetylated and deacetylated chitooligomers (Hexamers) on short-term expansion (7 days) and osteogenic differentiation of bone-marrow derived, human mesenchymal stem cells in terms of gene expression, cytokine secretion and quality of osteogenic differentiation. We show that chitooligomers affect hMSC gene expression and cytokine secretion, but not mineralization. The effect of chitooligomers was shown to be dependent on the acetylation degree, with significantly stronger effects when cells are stimulated with chitin-derived Hexamers (N-Acetyl Chitohexaose) than with Chitosan Hexamers (Chitohexaose).

Expression of Transcriptional Factor Genes (Oct-4, Nanog, and Sox-2) and Embryonic Stem Cell-Like Characters in Placental Membrane of Buffalo (Bubalus bubalis)

The aim of the study was to assess the expression of transcriptional factor genes and embryonic stem cell-like characters in the placental membrane of buffalo (Bubalus bubalis). Along with the placenta, amniotic fluid, maternal peripheral blood, and umbilical cord blood samples were taken for the future study. The isolation and culture of cells from the placental membrane was followed by the determination of RT-PCR-based markers (Oct-4, Nanog, Sox-2, alkaline phosphatase, stem cell factor, and Nestin) of these cells. Placental membrane cells also positively expressed alkaline phosphatase staining. We isolated adherent cells from trypsin-EDTA-digested placentas and examined these cells for morphology, surface markers, and differentiation potential and found that they expressed several stem cell markers. They also showed neurogenic and adipogenic differentiation potentials under appropriate guided conditions. We suggest that placenta-derived cells have multilineage differentiation potential similar to mesenchymal stem cells in terms of morphology and cell-surface antigen expression. The placenta may prove to be a useful source of mesenchymal stem cells.

Brain‐derived neurotrophic factor stimulates the neural differentiation of human umbilical cord blood‐derived mesenchymal stem cells and survival of differentiated cells through MAPK/ERK and PI3K/Akt‐dependent signaling pathways

Brain-derived neurotrophic factor (BDNF) plays an important role in the differentiation, development, and survival of neural stem cells. In this study, we analyzed its effects on the stimulation of human umbilical cord blood-derived mesenchymal stem cells in terms of their potential to differentiate into neuron-like cells, their survival characteristics, and the molecular mechanisms involved. The treatment of cells with neural induction medium (NIM) and BDNF generated more cells that were neuron-like and produced stronger expression of neural-lineage markers than cells treated with NIM and without BDNF. Raf-1 and ERK phosphorylation and p35 expression levels increased significantly in cells treated with both NIM and BDNF. This treatment also effectively blocked cell death following neural induction and increased Akt phosphorylation and Bcl2 expression compared with cells treated with NIM without BDNF. Inhibition of ERKs inhibited the BDNF-stimulated up-regulation of p35 and Bcl2. In addition, the inhibition of PI3K abrogated Akt phosphorylation and Bcl2 expression, but not p35 expression. Thus, MAPK/ERK-dependent p35 up-regulation and MAPK/ERK-dependent and PI3K/Akt-dependent Bcl2 up-regulation contribute to BDNF-stimulated neural differentiation and to the survival of differentiated cells.