Current Issue : April - June Volume : 2017 Issue Number : 2 Articles : 5 Articles
Background: Human embryonic stem cells (hESCs) partially recapitulate early embryonic three germ layer\ndevelopment, allowing testing of potential teratogenic hazards. Because use of hESCs is ethically debated, we\ninvestigated the potential for human induced pluripotent stem cells (hiPSCs) to replace hESCs in such tests.\nMethods: Three cell lines, comprising hiPSCs (foreskin and IMR90) and hESCs (H9) were differentiated for 14 days.\nTheir transcriptome profiles were obtained on day 0 and day 14 and analyzed by comprehensive bioinformatics tools.\nResults: The transcriptomes on day 14 showed that more than 70% of the ââ?¬Å?developmental genesââ?¬Â (regulated genes\nwith > 2-fold change on day 14 compared to day 0) exhibited variability among cell lines. The developmental genes\nbelonging to all three cell lines captured biological processes and KEGG pathways related to all three germ layer\nembryonic development. In addition, transcriptome profiles were obtained after 14 days of exposure to teratogenic\nvalproic acid (VPA) during differentiation. Although the differentially regulated genes between treated and untreated\nsamples showed more than 90% variability among cell lines, VPA clearly antagonized the expression of developmental\ngenes in all cell lines: suppressing upregulated developmental genes, while inducing downregulated ones. To quantify\nVPA-disturbed development based on developmental genes, we estimated the ââ?¬Å?developmental potencyââ?¬Â (Dp) and\nââ?¬Å?developmental indexââ?¬Â (Di).\nConclusions: Despite differences in genes deregulated by VPA, uniform Di values were obtained for all three cell lines.\nGiven that the Di values for VPA were similar for hESCs and hiPSCs, Di can be used for robust hazard identification,\nirrespective of whether hESCs or hiPSCs are used in the test systems....
The Charcot-Marie-Tooth disease 2F (CMT2F) and distal hereditary motor neuropathy 2B (dHMN2B) are caused by autosomal\ndominantly inherited mutations of the heat shock 27 kDa protein 1 (HSPB1) gene and there are no specific therapies available yet.\nHere, we assessed the potential therapeutic effect of HDAC6 inhibitors on peripheral neuropathy with HSPB1 mutation using in\nvitro model of motor neurons derived from induced pluripotent stem cells (iPSCs) of CMT2F and dHMN2B patients. The absolute\nvelocity of mitochondrial movements and the percentage of moving mitochondria in axons were lower both in CMT2F-motor\nneurons and in dHMN2B-motor neurons than those in controls, and the severity of the defective mitochondrial movement was\ndifferent between the two disease models. CMT2F-motor neurons and dHMN2B-motor neurons also showed reduced...
The recent advent of induced pluripotent stem cells (iPSCs) and gene therapy tools has raised the possibility of autologous cell therapy\nfor rare genetic diseases.However, cellular reprogramming is inefficient in certain diseases such as ataxia telangiectasia, Fanconi\nanemia, LIG4 syndrome, and fibrodysplasia ossificans progressiva syndrome, owing to interference of the disease-related genes. To\novercome these therapeutic limitations, it is necessary to fundamentally correct the abnormal gene during or prior to the reprogramming\nprocess. In addition, as genetic etiology of Parkinson�s disease, it has been well known that induced neural stem cells (iNSCs)\nwere progressively depleted by LRRK2 gene mutation, LRRK2 (G2019S).Thus, to maintain the induced NSCs directly derived from\nPD patient cells harboring LRRK2 (G2019S), it would be ideal to simultaneously treat the LRRK2 (G2019S) fibroblast during the process\nof TD. Therefore, simultaneous reprogramming (or TD) and gene therapy would provide the solution for therapeutic limitation\ncaused by vulnerability of reprogramming or TD, in addition to being suitable for general application to the generation of autologous\ncell-therapy products for patients with genetic defects, thereby obviating the need for the arduous processes currently required....
Background: Nitric oxide (NO) plays a role in a number of physiological processes including stem cell differentiation\nand osteogenesis. Endothelial nitric oxide synthase (eNOS), one of three NO-producing enzymes, is located in a close\nconformation with the caveolin-1 (CAV-1WT) membrane protein which is inhibitory to NO production. Modification of\nthis interaction through mutation of the caveolin scaffold domain can increase NO release. In this study, we genetically\nmodified equine adipose-derived stem cells (eASCs) with eNOS, CAV-1WT, and a CAV-1F92A (CAV-1WT mutant) and\nassessed NO-mediated osteogenic differentiation and the relationship with the Wnt signaling pathway.\nMethods: NO production was enhanced by lentiviral vector co-delivery of eNOS and CAV-1F92A to eASCs, and\nosteogenesis and Wnt signaling was assessed by gene expression analysis and activity of a novel Runx2-GFP reporter.\nCells were also exposed to a NO donor (NONOate) and the eNOS inhibitor, L-NAME.\nResults: NO production as measured by nitrite was significantly increased in eNOS and CAV-1F92A transduced eASCs\n+(5.59 �± 0.22 �¼M) compared to eNOS alone (4.81 �± 0.59 �¼M) and un-transduced control cells (0.91 �± 0.23 �¼M) (p < 0.05).\nDuring osteogenic differentiation, higher NO correlated with increased calcium deposition, Runx2, and alkaline\nphosphatase (ALP) gene expression and the activity of a Runx2-eGFP reporter. Co-expression of eNOS and CAV-1WT\ntransgenes resulted in lower NO production. Canonical Wnt signaling pathway-associated Wnt3a and Wnt8a gene\nexpressions were increased in eNOS-CAV-1F92A cells undergoing osteogenesis whilst non-canonical Wnt5a was\ndecreased and similar results were seen with NONOate treatment. Treatment of osteogenic cultures with 2 mMLNAME\nresulted in reduced Runx2, ALP, and Wnt3a expressions, whilst Wnt5a expression was increased in eNOSdelivered\ncells. Co-transduction of eASCs with a Wnt pathway responsive lenti-TCF/LEF-dGFP reporter only showed\nactivity in osteogenic cultures co-transduced with a doxycycline inducible eNOS. Lentiviral vector expression of\ncanonical Wnt3a and non-canonical Wnt5a in eASCs was associated with induced and suppressed osteogenic\ndifferentiation, respectively, whilst treatment of eNOS-osteogenic cells with the Wnt inhibitor Dkk-1 significantly\nreduced expressions of Runx2 and ALP.\nConclusions: This study identifies NO as a regulator of canonical Wnt/�²-catenin signaling to promote osteogenesis in\neASCs which may contribute to novel bone regeneration strategies....
Muse cells are a novel population of nontumorigenic pluripotent stem cells, highly resistant to cellular stress. These cells are present\nin every connective tissue and intrinsically express pluripotent stemmarkers such asNanog,Oct3/4, Sox2, and TRA1-60.Muse cells\nare able to differentiate into cells from all three embryonic germ layers both spontaneously and under media-specific induction.\nUnlike ESCs and iPSCs, Muse cells exhibit low telomerase activity and asymmetric division and do not undergo tumorigenesis or\nteratoma formation when transplanted into a host organism. Muse cells have a high capacity for homing into damaged tissue and\nspontaneous differentiation into cells of compatible tissue, leading to tissue repair and functional restoration.The ability of Muse\ncells to restore tissue function may demonstrate the role of Muse cells in a highly conserved cellular mechanism related to cell\nsurvival and regeneration, in response to cellular stress and acute injury. From an evolutionary standpoint, genes pertaining to the\nregenerative capacity of an organism have been lost in higher mammals from more primitive species. Therefore, Muse cells may\noffer insight into the molecular and evolutionary bases of autonomous tissue regeneration and elucidate the molecular and cellular\nmechanisms that prevent mammals from regenerating limbs and organs, as planarians, newts, zebrafish, and salamanders do....
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