Project description:Niemann-Pick type C (NPC) disease is a fatal neurodegenerative disorder characterized by the accumulation of unesterified cholesterol in the late endosomal/lysosomal compartments. Mutations in the NPC1 protein are implicated in 95% of patients with NPC disease. The most prevalent mutation is the missense mutation I1061T that occurs in approximately 15–20% of disease alleles. In this study, we have performed an isobaric labeling based quantitative analysis of proteome of NPC1-I1061T versus wild-type primary fibroblasts.
Project description:Niemann-Pick type C disease is a rare neurodegenerative disorder mainly caused by mutations in Npc1, resulting in abnormal late endosomal/lysosomal lipid storage. Although microgliosis is a prominent pathological feature, direct consequences of NPC1 loss on microglial function remain uncharacterized. Previously, we have characterized microglial proteome alterations in the NPC1 KO mouse model (PXD019447). In order to investigate similar changes in humans, we have cultured monocyte derived macrophages of NPC1 patients and control donors.
Project description:Recent studies on developing three-dimensional (3D) brain organoids from stem cells have allowed the generation of in vitro models of neural disease and have enabled the screening of drugs because these organoids mimic the complexity of neural tissue. Niemann-Pick disease, type C (NPC) is a neurodegenerative lysosomal storage disorder caused by mutations in the NPC1 protein. The pathological features underlying NPC are characterized by the abnormal accumulation of cholesterol in acidic compartments, including late endosomes and lysosomes. Due to the inaccessibility of brain tissues from human NPC patients, we developed NPC brain organoids with induced neural stem cells from NPC patient-derived fibroblasts. NPC organoids exhibit significantly reduced size and proliferative ability, which are accompanied by accumulation of cholesterol, impairment in neuronal differentiation and autophagic flux and dysfunction of lysosomes; therefore, NPC organoids can recapitulate the main phenotypes of NPC patients. Furthermore, these pathological phenotypes observed in NPC organoids were reversed by treatment with valproic acid, which is known to be an effective treatment for several neurodegenerative diseases. Our data present patient-specific phenotypes in 3D organoid-based models of NPC and highlight the application of this model to drug screening in vitro.
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.