EC:2.3.1.107 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.3.1.107 (DAT)
1,471 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neural stem cells (NSCs) are powerful research tools for the design and discovery of new approaches to cell therapy in neurodegenerative diseases like Parkinson's disease. Several epigenetic and genetic strategies have been tested for long-term maintenance and expansion of these cells in vitro. Here we report the generation of a new stable cell line of human neural stem cells derived from ventral mesencephalon (hVM1) based on v-myc immortalization. The cells expressed neural stem cell and radial glia markers like nestin, vimentin and 3CB2 under proliferation conditions. After withdrawal of growth factors, proliferation and expression of v-myc were dramatically reduced and the cells differentiated into astrocytes, oligodendrocytes and neurons. hVM1 cells yield a large number of dopaminergic neurons (about 12% of total cells are TH+) after differentiation, which also produce dopamine. In addition to proneural genes (NGN2, MASH1), differentiated cells show expression of several genuine mesencephalic dopaminergic markers such as: LMX1A, LMX1B, GIRK2, ADH2, NURR1, PITX3, VMAT2 and DAT, indicating that they retain their regional identity. Our data indicate that this cell line and its clonal derivatives may constitute good candidates for the study of development and physiology of human dopaminergic neurons in vitro, and to develop tools for Parkinson's disease cell replacement preclinical research and drug testing.
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PMID:Generation and properties of a new human ventral mesencephalic neural stem cell line. 1932 51

The transcription factor Nurr1 is expressed in the mouse olfactory bulb (OB), although it remains unknown whether it influences the generation of dopaminergic neurons (DA) (DA neurons) in cells isolated from this brain region. We found that expressing Nurr1 in proliferating olfactory bulb stem cells (OBSCs) produces a marked inhibition of cell proliferation and the generation of immature neurons immunoreactive for tyrosine hydroxylase (TH) concomitant with marked upregulations of Th, Dat, Gad, and Fgfr2 transcripts. In long-term cultures, these cells develop neurochemical and synaptic markers of mature-like mesencephalic DA neurons, expressing GIRK2, VMAT2, DAT, calretinin, calbindin, synapsin-I, and SV2. Concurring with the increase in both Th and Gad expression, a subpopulation of induced cells was both TH- and GAD-immunoreactive indicating that they are dopaminergic-GABAergic neurons. Indeed, these cells could mature to express VGAT, suggesting they can uptake and store GABA in vesicles. Remarkably, the dopamine D1 receptor agonist SKF-38393 induced c-Fos in TH(+) cells and dopamine release was detected in these cultures under basal and KCl-evoked conditions. By contrast, cotransducing the Neurogenin2 and Nurr1 transcription factors produced a significant decrease in the number of TH-positive neurons. Our results indicate that Nurr1 overexpression in OBSCs induces the formation of two populations of mature dopaminergic neurons with features of the ventral mesencephalon or of the OB, capable of responding to functional dopaminergic stimuli and of releasing dopamine. They also suggest that the accumulation of Fgfr2 by Nurr1 in OBSCs may be involved in the generation of DA neurons.
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PMID:Nurr1 blocks the mitogenic effect of FGF-2 and EGF, inducing olfactory bulb neural stem cells to adopt dopaminergic and dopaminergic-GABAergic neuronal phenotypes. 2544 75

We previously reported that non-narcotic antitussives possessing inhibitory actions on G protein-coupled inwardly rectifying potassium (GIRK) channels have antidepressant-like effects in the forced swimming test in normal and adrenocoticotropic hormone (ACTH) treated rats. Furthermore, the antidepressant-like effects of the antitussives such as tipepidine were blocked by dopamine D₁ receptor antagonist, and inhibitory actions on GIRK channels of dopamine neurons may be involved in the antidepressant-like effects of tipepidine. In this study, we generated GIRK2^DATKO mice with Girk2/Kcnj6 conditional deletion and assessed depression-related behavior of the mice. The Cre/loxP system was used to selectively delete GIRK2 subunit containing GIRK channels in the neurons expressing dopamine transporter. First, deletion of GIRK2 subunits in the ventral tegmental area (VTA) neurons expressing dopamine transporters was confirmed by hisitochemically and electrophysiologically. In the mice, a significant decrease in the immobility time of forced swimming test was observed. Locomotor activity of the mice was not changed compared to that of GIRK2^floxed mice, when tested in the open field. These results suggest that the antidepressant-like effect of antitussives such as tipepidine may be caused partly through the inhibitory actions on GIRK channels in the dopamine neurons.
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PMID:Deletion of GIRK2 subunit containing GIRK channels of neurons expressing dopamine transporter decrease immobility time on forced swimming in mice. 2918 Jan 15

Reprogramming technology holds great promise for the study and treatment of Parkinson's disease (PD) as patient-specific ventral midbrain dopamine (vmDA) neurons can be generated. This should facilitate the investigation of early changes occurring during PD pathogenesis, permitting the identification of new drug targets and providing a platform for drug screening. To date, most studies using reprogramming technology to study PD have employed induced pluripotent stem cells. Research into PD using direct reprogramming has been limited due to an inability to generate high yields of authentic human vmDA neurons. Nevertheless, direct reprogramming offers a number of advantages, and development of this technology is warranted. Previous reports have indicated that induced neural precursors (iNPs) derived from adult human fibroblasts by lineage factor-mediated direct reprogramming can give rise to dopamine neurons expressing tyrosine hydroxylase (TH+). Using normal adult human fibroblasts, the present study aimed to extend these findings and determine the capacity of iNPs for generating vmDA neurons, with the aim of utilising this technology for the future study of PD. While iNPs expressed late vmDA fate markers such as NURR1 and PITX3, critical early regional markers LMX1A, FOXA2 and EN1 were not expressed. Upon differentiation, iNPs gave rise to dopamine neuronal-like cells expressing TUJ1, TH, AADC, DAT, VMAT2 and GIRK2. To induce an authentic A9 phenotype, a series of experiments investigated temporal exposure to patterning factors. Exposure to SHH-C24II, purmorphamine, CHIR99021 and/or FGF8b during or after reprogramming was insufficient to induce expression of early vmDA regional markers. Addition of LMX1A/FOXA2 to the transfection cocktail did not induce a sustained vmDA iNP phenotype. This study reports for the first time that iNPs derived from healthy adult human cells by non-viral expression of lineage factors can give rise to dopamine neuronal-like cells. Direct-to-iNP reprogramming could be a suitable strategy for modelling PD in vitro using aged donor-derived cells.
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PMID:Generation of dopamine neuronal-like cells from induced neural precursors derived from adult human cells by non-viral expression of lineage factors. 3001 71