Correct timing of neurogenesis is critical for generating the correct number and subtypes of glia and neurons in the embryo, and for preventing tumours and stem cell depletion in the adults. Here we analyse how the midbrain dopamine neuron (mDA) progenitors transition into cell cycle arrest (G0) and begin to mature into ependymal cells. The comparison of mDA progenitors from different embryonic stages revealed the upregulation of Nfi and Sox9 transcription factors during development.
View Article and Find Full Text PDFMidbrain dopamine (mDA) neurons comprise diverse cells with unique innervation targets and functions. This is illustrated by the selective sensitivity of mDA neurons of the substantia nigra compacta (SNc) in patients with Parkinson's disease, while those in the ventral tegmental area (VTA) are relatively spared. Here, we used single nuclei RNA sequencing (snRNA-seq) of approximately 70,000 mouse midbrain cells to build a high-resolution atlas of mouse mDA neuron diversity at the molecular level.
View Article and Find Full Text PDFHow neurons can maintain cellular identity over an entire life span remains largely unknown. Here, we show that maintenance of identity in differentiated dopaminergic and serotonergic neurons is critically reliant on the Polycomb repressive complex 2 (PRC2). Deletion of the obligate PRC2 component, , in these neurons resulted in global loss of H3K27me3, followed by a gradual activation of genes harboring both H3K27me3 and H3K9me3 modifications.
View Article and Find Full Text PDFAnalyses of gene expression in cells affected by neurodegenerative disease can provide important insights into disease mechanisms and relevant stress response pathways. Major symptoms in Parkinson's disease (PD) are caused by the degeneration of midbrain dopamine (mDA) neurons within the substantia nigra. Here we isolated neuromelanin-positive dopamine neurons by laser capture microdissection from human substantia nigra samples recovered at both early and advanced stages of PD.
View Article and Find Full Text PDFDopamine (DA) neurons of the midbrain are at risk to become affected by mitochondrial damage over time and mitochondrial defects have been frequently reported in Parkinson's disease (PD) patients. However, the causal contribution of adult-onset mitochondrial dysfunction to PD remains uncertain. Here, we developed a mouse model lacking Mitofusin 2 (MFN2), a key regulator of mitochondrial network homeostasis, in adult midbrain DA neurons.
View Article and Find Full Text PDFAn amendment to this paper has been published and can be accessed via a link at the top of the paper.
View Article and Find Full Text PDFCell replacement is a long-standing and realistic goal for the treatment of Parkinson's disease (PD). Cells for transplantation can be obtained from fetal brain tissue or from stem cells. However, after transplantation, dopamine (DA) neurons are seen to be a minor component of grafts, and it has remained difficult to determine the identity of other cell types.
View Article and Find Full Text PDFMidbrain dopamine (mDA) neurons constitute a heterogenous group of cells that have been intensely studied, not least because their degeneration causes major symptoms in Parkinson's disease. Understanding the diversity of mDA neurons - previously well characterized anatomically - requires a systematic molecular classification at the genome-wide gene expression level. Here, we use single cell RNA sequencing of isolated mouse neurons expressing the transcription factor Pitx3, a marker for mDA neurons.
View Article and Find Full Text PDFStem cell engineering and grafting of mesencephalic dopamine (mesDA) neurons is a promising strategy for brain repair in Parkinson's disease (PD). Refinement of differentiation protocols to optimize this approach will require deeper understanding of mesDA neuron development. Here, we studied this process using transcriptome-wide single-cell RNA sequencing of mouse neural progenitors expressing the mesDA neuron determinant Lmx1a.
View Article and Find Full Text PDFUnlabelled: α-synuclein, a protein enriched in Lewy bodies and highly implicated in neurotoxicity in Parkinson's disease, is distributed both at nerve terminals and in the cell nucleus. Here we show that a nuclear derivative of α-synuclein induces more pronounced changes at the gene expression level in mouse primary dopamine (DA) neurons compared to a derivative that is excluded from the nucleus. Moreover, by RNA sequencing we analyzed the extent of genome-wide effects on gene expression resulting from expression of human α-synuclein in primary mouse DA neurons.
View Article and Find Full Text PDFAm J Physiol Gastrointest Liver Physiol
October 2015
Neuropeptide S (NPS) receptor (NPSR1) polymorphisms are associated with enteral dysmotility and inflammatory bowel disease (IBD). This study investigated the role of NPS in conjunction with nitrergic mechanisms in the regulation of intestinal motility and mucosal permeability. In rats, small intestinal myoelectric activity and luminal pressure changes in small intestine and colon, along with duodenal permeability, were studied.
View Article and Find Full Text PDFYF476 differs from the proton pump inhibitor (PPI) esomeprazole in mode of action by antagonizing the type 2 receptor of cholecystokinin/gastrin (CCK-2R). YF476 protection against diclofenac-induced gastric ulcers was compared to esomeprazole and correlated with plasma levels of hormones related to gastric pH (gastrin, ghrelin, and somatostatin), gastric gene expression of these hormones, their receptors, and inducible nitric oxide synthase (iNOS). YF476 or esomeprazole pretreatments were followed by diclofenac.
View Article and Find Full Text PDFScand J Gastroenterol
November 2012
Objective: To reveal specific gene activation in nitric oxide (NO)-related inflammation we studied differential gene expression in inflammatory bowel disease (IBD).
Methods: Total RNA was isolated from 20 biopsies of inflamed mucosa from Crohn's disease (CD) and ulcerative colitis (UC) patients each as well as from six controls, labeled with (32)P-dCTP and hybridized to a human NO gene array. Significant genes were analyzed for functional gene interactions and heatmaps generated by hierarchical clustering.
Neuronal networks originating in the hypothalamic arcuate nucleus play fundamental roles in the control of energy balance. Neuropeptide Y (NPY)-producing neurons in the arcuate nucleus stimulate food intake, whereas arcuate nucleus neurons that release the proopiomelanocortin (POMC)-derived peptide alpha-melanocyte-stimulating hormone (alpha-MSH) potently reduce food intake. Relatively little attention has been focused on classical neurotransmitters in regulation of food intake.
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