Project description:Purkinje cells (PC) of the cerebellum degenerate in adult mice with mutations in the Niemann-Pick type C (NPC) disease 1 (Npc1) gene. We subjected BALB/c Npc1+/+ and Npc1-/- mouse cerebella from an early and a later time point of PC degeneration to a genome-wide microarray gene expression analysis. We found general underrepresentation of PC-specific transcripts, consistent with PC loss, and elevated markers of microglia activation at the later time point. Keywords: Niemann-Pick type C, Purkinje cell degeneration
Project description:Macrophage inflammatory protein 1alpha/CCL3 protein is a known pro-inflammatory cytokine that can mediate chemotaxis of monocytes and promote cell degranulation. Ccl3 gene expression is elevated in the CNS and visceral tissue of many lysosomal storage disorders. The deletion of Ccl3 in a mouse model of Sandhoff disease was reported to result in reduced monocyte-associated pathology in the brain, delayed neurodegeneration, and prolonged health. However, deletion of Ccl3 in a mouse model of Niemann-Pick C disease was dentrimental or neutral instead of beneficial. Prevention of neuronal loss was instead mediated by providing NPC1 to neurons. We used microarrays to detail the global change in gene expression of the cerebellum in Niemann-Pick C disease animals, Niemann-Pick C disease animals with Ccl3 gene deletion, and Niemann-Pick C disease animals with Purkinje neuron-specific NPC1-YFP rescue.
Project description:Macrophage inflammatory protein 1alpha/CCL3 protein is a known pro-inflammatory cytokine that can mediate chemotaxis of monocytes and promote cell degranulation. Ccl3 gene expression is elevated in the CNS and visceral tissue of many lysosomal storage disorders. The deletion of Ccl3 in a mouse model of Sandhoff disease was reported to result in reduced monocyte-associated pathology in the brain, delayed neurodegeneration, and prolonged health. However, deletion of Ccl3 in a mouse model of Niemann-Pick C disease was dentrimental or neutral instead of beneficial. Prevention of neuronal loss was instead mediated by providing NPC1 to neurons. We used microarrays to detail the global change in gene expression of the cerebellum in Niemann-Pick C disease animals, Niemann-Pick C disease animals with Ccl3 gene deletion, and Niemann-Pick C disease animals with Purkinje neuron-specific NPC1-YFP rescue. To identify the top ~50 genes elevated in NPC disease Npc1-/- (NPC) and Npc1+/- (WT) mice were compared at age P50; To profile changes in gene expression as a result of Ccl3 gene deletion Ccl3-/-;Npc1-/- mice were compared against Npc1-/- mice across various ages; To profile changes in gene expression as a result of Purkinje neuron-sepcific NPC1 rescue P;N;Npc1-/- mice were compared against Npc1-/- mice across various ages.
Project description:Purkinje cells (PC) of the cerebellum degenerate in adult mice with mutations in the Niemann-Pick type C (NPC) disease 1 (Npc1) gene. We subjected BALB/c Npc1+/+ and Npc1-/- mouse cerebella from an early and a later time point of PC degeneration to a genome-wide microarray gene expression analysis. We found general underrepresentation of PC-specific transcripts, consistent with PC loss, and elevated markers of microglia activation at the later time point. Experiment Overall Design: 12 BALB/c Npc1 mice of the two ages P21 and P49 and the two genotypes Npc1+/+ and Npc1-/- were used, 3 replicates for each age and genotype. The animals were of the same breed and lived under identical housing conditions. All except one animal were female. The animals were not further treated, but only sacrificed at P21 or P49.
Project description:Quantitative, Label-Free Proteomics in the Symptomatic Niemann-Pick, Type C1 Mouse Model Using Standard Flow Liquid Chromatography and Thermal Focusing Electrospray Ionization
Project description:Superparamagnetic iron oxide nanoparticles (SPIONs) have so far mainly been used as cellular carriers for genes and therapeutic products, while their use in subcellular organelle isolation remains largely underexploited. We engineered surface functionalized SPIONs (Ø 10 nm) that target very distinct subcellular compartments. Anionic dimercaptosuccinic acid-coated SPIONs are efficiently internalized and accumulate time-dependently in late endosomes and lysosomes, while cationic aminolipid-coated SPIONs surprisingly strongly reside considerably at the plasma membrane. These features allowed us to establish standardized magnetic isolation procedures for late endosomes/lysosomes and plasma membranes with as consolidated by biochemical, ultrastructural analyses, and to a yield and purity allowing subsequent proteomic and lipidomic profiling. We validated the strength of our approach by comparing the biomolecular compositions of lysosomes and plasma membranes isolated from wild-type and HeLa to those of HeLa cells deficient in Niemann-Pick disease type C1 (NPC1) deficient HeLa cells expression. While the plasma membrane composition remaineds largely unaltered, pronounced alterations in several protein and lipid species including cholesterol wereare observed in isolated lysosomes reflecting vesicular transport obstruction jamming and deficient lysosomal turnover resulting from NPC1 deficiency. The technology thus allows high-resolution analysis of proteins and lipids. It also, and provides a major advance step forward in fingerprinting subcellular compartments, with an increased potential to identify subtle alterations in biomolecular compositions of lysosomes and/or plasma membranes.
Project description:Niemann-Pick Type C disease is an autosomal recessive neurodegenerative disorder with abnormal lipid storage as the major cellular pathologic hallmark. Genetic analyses have identified mutations in NPC1 gene in the great majority of cases, while mutations in NPC2 account for the remainders. Yet, little is known regarding the cellular mechanisms responsible for NPC pathogenesis, especially for neurodegeneration, which is the usual cause of death. To identify critical steps that could account for the pathological manifestations of the disease in one of the most affected brain structures, we performed global gene expression analysis in the cerebellum from three-week old Npc1+/+ and Npc1-/- mice with two different microarray platforms (Agilent and Illumina). Our results provide novel molecular insight regarding the mechanisms of pathogenesis in NPC disease and reveal potential new therapeutic targets.