nQuant Enables Precise Quantitative N-Glycomics.

N-glycosylation is a highly heterogeneous post-translational modification that modulates protein function. Defects in N-glycosylation are directly linked to various human diseases. Despite the importance of quantifying N-glycans with high precision, existing glycoinformatics tools are limited.

Genetically Modified Mesenchymal Stromal Cells in Cartilage Regeneration.

Articular cartilage injury is common in various conditions, including osteoarthritis, rheumatic diseases, and trauma. Current treatments for cartilage injury fail to completely regenerate the damaged cartilage. Mesenchymal stromal cells (MSCs) have emerged as potential candidates for cartilage regeneration.

Systematic expression analysis of plasticity-related genes in mouse brain development brings PRG4 into play.

Background: Plasticity-related genes (Prgs/PRGs) or lipid phosphate phosphatase-related proteins (LPPRs) comprise five known members, which have been linked to neuronal differentiation processes, such as neurite outgrowth, axonal branching, or dendritic spine formation. PRGs are highly brain-specific and belong to the lipid phosphate phosphatases (LPPs) superfamily, which influence lipid metabolism by dephosphorylation of bioactive lipids. PRGs, however, do not possess enzymatic activity, but modify lipid metabolism in a way that is still under investigation.

Identification of Brain-Specific Treatment Effects in NPC1 Disease by Focusing on Cellular and Molecular Changes of Sphingosine-1-Phosphate Metabolism.

Niemann-Pick type C1 (NPC1) is a lysosomal storage disorder, inherited as an autosomal-recessive trait. Mutations in the gene result in malfunction of the NPC1 protein, leading to an accumulation of unesterified cholesterol and glycosphingolipids. Beside visceral symptoms like hepatosplenomegaly, severe neurological symptoms such as ataxia occur.

Stimulation of mGluR1/5 Improves Defective Internalization of AMPA Receptors in NPC1 Mutant Mouse.

Niemann-Pick type C1 (NPC1) disease is characterized by neurodegeneration caused by cholesterol accumulation in the late endosome/lysosome. In this study, a defective basal and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-stimulated internalization of GluR2-containing AMPA receptors in NPC1-/- cortical neurons was detected. Our results show that the amount of cholesterol and group I metabotropic glutamate receptors (mGluR1/5) in lipid rafts of NPC1-/- cortical tissue and neurons are decreased and their downstream signals of p-ERK are defective, which are restored by a rebalance of cholesterol homeostasis through β-cyclodextrin (β-CD) treatment.

Proteomics of the corpus callosum to identify novel factors involved in hypomyelinated Niemann-Pick Type C disease mice.

Hypomyelination in the central nerves system (CNS) is one of the most obviously pathological features in Niemann-Pick Type C disease (NPC), which is a rare neurodegenerative disorder caused by mutations in the NPC intracellular cholesterol transporter 1 or 2 (Npc1 or Npc2). Npc1 plays key roles in both neurons and oligodendrocytes during myelination, however, the linkage between the disturbed cholesterol transport and inhibited myelination is unrevealed. In this study, mass spectrometry (MS)-based differential quantitative proteomics was applied to compare protein composition in the corpus callosum between wild type (WT) and NPC mice.

LPA , LPA , LPA , and LPA receptor expression during mouse brain development.

Background: LPA is a small bioactive phospholipid that acts as an extracellular signaling molecule and is involved in cellular processes, including cell proliferation, migration, and differentiation. LPA acts by binding and activating at least six known G protein-coupled receptors: LPA . In recent years, LPA has been suggested to play an important role both in normal neuronal development and under pathological conditions in the nervous system.

Control of hepatic gluconeogenesis by Argonaute2.

Objective: The liver performs a central role in regulating energy homeostasis by increasing glucose output during fasting. Recent studies on Argonaute2 (Ago2), a key RNA-binding protein mediating the microRNA pathway, have illustrated its role in adaptive mechanisms according to changes in metabolic demand. Here we sought to characterize the functional role of Ago2 in the liver in the maintenance of systemic glucose homeostasis.

Altered myelination in the Niemann-Pick type C1 mutant mouse.

Niemann-Pick type C1 (NPC1) disease is a lysosomal storage disorder caused by mutation of Npc1 or Npc2 gene, resulting in various progressive pathological features. Myelin defection is a major pathological problem in Npc1 mutant mice; however, impairment of myelin proteins in the developing brain is still incompletely understood. In this study, we showed that the expression of myelin genes and proteins is strongly inhibited from postnatal day 35 onwards including reduced myelin basic protein (MBP) expression in the brain.

Improvement of impaired electrical activity in NPC1 mutant cortical neurons upon DHPG stimulation detected by micro-electrode array.

Niemann-Pick Type C1 (NPC1) disease is an autosomal recessive neurodegenerative disease characterized by an excessive accumulation of unesterified cholesterol in late endosomes/lysosomes. Patients with NPC1 disease show a series of symptoms in neuropathology, including a gradually increased loss of motor control and seizures. However, mechanism of the neurological manifestations in NPC1 disease is not fully understood yet.

Lovastatin promotes myelin formation in NPC1 mutant oligodendrocytes.

Niemann-Pick Type C (NPC) disease is a rare neurovisceral disorder caused by mutations of either NPC1 or NPC2 gene and characterized by defective intracellular transport of cholesterol and glycosphingolipids, leading to neuron loss and myelin aberration in the central nervous system. In this study, by comparing protein expression in the cortical white matter tracts from mice at different postnatal days, we identified that in the NPC1 mutant (NPC1) mice, the onset of myelination is delayed and the amount of the major myelin protein MBP and PLP, and oligodendrocyte regulatory factor Olig1 and Olig2, but not NG2 and Sox10, decreased significantly, suggesting a disruption of oligodendrocyte differentiation. Furthermore, in in vitro oligodendrocyte cultivation, NPC1 oligodendrocytes showed less response to the stimulation of neuron-conditioned medium (CdM), indicating a defect of oligodendrocyte per se.

ADAM23 promotes neuronal differentiation of human neural progenitor cells.

Background: ADAM23 is widely expressed in the embryonic central nervous system and plays an important role in tissue formation.

Results: In this study, we showed that ADAM23 contributes to cell survival and is involved in neuronal differentiation during the differentiation of human neural progenitor cells (hNPCs). Upregulation of ADAM23 in hNPCs was found to increase the number of neurons and the length of neurite, while its downregulation decreases them and triggers cell apoptosis.

Non-canonical pathway induced by Wnt3a regulates β-catenin via Pyk2 in differentiating human neural progenitor cells.

Wnt/β-catenin and Wnt/Ca pathways are involved in cellular processes during embryonic development and the interaction between them in the same cell decides the outcome of cellular functions. In this study, we showed that Wnt3a triggers the Wnt/Ca signaling pathway, indicated by an increase of cytosolic free calcium ([Ca]) and activation of calmodulin dependent kinase II (CaMKII) during the differentiation of human neuronal progenitor cells (hNPCs). Wnt3a via the increase of [Ca] activates proline-rich tyrosine kinase 2 (Pyk2), which subsequently regulates phosphorylation of glycogen synthase kinase 3β (GSK3β) and β-catenin stabilization.

Defects in the retina of Niemann-pick type C 1 mutant mice.

Background: Niemann-Pick type C1 (NPC1) disease is an inherited lysosomal storage disease caused by mutation of the Npc1 gene, resulting in a progressive accumulation of unesterified cholesterol and glycolipids in lysosomes of multiple tissues and leading to neurodegeneration and other disease. In Npc1 mutant mice, retinal degeneration including impaired visual function, lipofuscin accumulation in the pigment epithelium and ganglion cells as well as photoreceptor defects has been found. However, the pathologies of other individual cell types of the retina in Npc1 mutant mice are still not fully clear.

Aberrant expressions of delta-protocadherins in the brain of Npc1 mutant mice.

Niemann-Pick type C1 (NPC1) disease is an autosomal recessive disorder characterized by dysmyelination and neurodegeneration, which can result in the death of patients in early childhood in some cases. Members of the delta-protocadherins (Pcdhs) play important roles in neurogenesis and brain development. In this study, we compared expression profiles of Pcdhs in the brain of both wild-type and Npc1 mutant mice from postnatal day (P) 9 onwards by in situ hybridization.

Hyperactive glial cells contribute to axonal pathologies in the spinal cord of Npc1 mutant mice.

Niemann-Pick disease type C1 (NPC1) is a neurodegenerative disease with various progressive pathological features, for example, neuronal loss, dysmyelination, abnormal axon swelling, and gliosis, in the brain. Pathological activation of p38-mitogen-activated protein kinase (MAPK) results in hyperphosphorylation of tau protein, which contributes to the development of neurodegenerative diseases. In this study, axonal varicosities or spheroids and presynaptic aggregates in the spinal cord of the Npc1 mutant mice were found from postnatal day (P) 35 onwards, as indicated by the increased hyperphosphorylated neurofilament and synaptophysin immunoreactivity as well as the findings from electron microscopy.

Nanog expression in heart tissues induced by acute myocardial infarction.

Nanog is a potential stem cell marker and is considered a regeneration factor during tissue repair. In the present study, we investigated expression patterns of nanog in the rat heart after acute myocardial infarction by semi-quantitative RT-PCR, immunohistochemistry and Western blot analyses. Our results show that nanog at both mRNA and protein levels is positively expressed in myocardial cells, fibroblasts and small round cells in different myocardial zones at different stages after myocardial infarction, showing a spatio-temporal and dynamic change.

ADAM10 negatively regulates neuronal differentiation during spinal cord development.

Members of the ADAM (a disintegrin and metalloprotease) family are involved in embryogenesis and tissue formation via their proteolytic function, cell-cell and cell-matrix interactions. ADAM10 is expressed temporally and spatially in the developing chicken spinal cord, but its function remains elusive. In the present study, we address this question by electroporating ADAM10 specific morpholino antisense oligonucleotides (ADAM10-mo) or dominant-negative ADAM10 (dn-ADAM10) plasmid into the developing chicken spinal cord as well as by in vitro cell culture investigation.

Olfactory deficits in Niemann-Pick type C1 (NPC1) disease.

Background: Niemann-Pick type C disease (NPC) is a rare autosomal recessive lipid storage disease characterized by progressive neurodegeneration. As only a few studies have been conducted on the impact of NPC on sensory systems, we used a mutant mouse model (NPC1(-/-)) to examine the effects of this disorder to morphologically distinct regions of the olfactory system, namely the olfactory epithelium (OE) and olfactory bulb (OB).

Methodology/principal Findings: For structural and functional analysis immunohistochemistry, electron microscopy, western blotting, and electrophysiology have been applied.

Expression patterns of the ADAMs in early developing chicken cochlea.

Members of the ADAM (a disintegrin and metalloprotease) family are type I transmembrane proteins involved in biological processes of proteolysis, cell adhesion, cell-matrix interaction, as well as in the intracellular signaling transduction. In the present study, expression patterns of seven members of the ADAM family were investigated at the early stages of the developing cochlea by in situ hybridization. The results show that each individual ADAM is expressed and regulated in the early developing cochlea.

Anatomical expression patterns of delta-protocadherins in developing chicken cochlea.

The delta-protocadherin (δ-Pcdh) family of transmembrane proteins belongs to the cadherin superfamily, which is involved in embryogenesis mediated by a homophilic binding during the embryonic development. In the present study, expression patterns of eight members of the δ-Pcdh family were investigated in the developing chicken cochlea by in situ hybridization. Our results provide a dynamical profile to show that the δ-Pcdhs are expressed spatially and temporally in the developing chicken cochleae.

Gene transfer into older chicken embryos by ex ovo electroporation.

The chicken embryo provides an excellent model system for studying gene function and regulation during embryonic development. In ovo electroporation is a powerful method to over-express exogenous genes or down-regulate endogenous genes in vivo in chicken embryos(1). Different structures such as DNA plasmids encoding genes(2-4), small interfering RNA (siRNA) plasmids(5), small synthetic RNA oligos(6), and morpholino antisense oligonucleotides(7) can be easily transfected into chicken embryos by electroporation.

Increased excitability and compromised long-term potentiation in the neocortex of NPC1(-/-) mice.

Niemann-Pick type C1 (NPC1) disease is a neurodegenerative lysosomal storage disorder caused by mutations in the NPC1 gene which encodes a transmembrane protein of the acidic compartment. Albeit the NPC1(-/-) mouse is available serving as an appropriate animal model of the human disease, the precise function of this protein remains obscure. Here, we investigated the synaptic consequences of this disease and explored long-term potentiation (LTP) in slices taken from the hippocampal CA1 region, the dorsomedial striatum as well as the somatosensory neocortex in NPC1(-/-) mice using extracellular field potential recordings.