Search results for "Surge"

Expression of endogenous mouse APP modulates β-amyloid deposition in hAPP-transgenic mice

2017

Amyloid-β (Aβ) deposition is one of the hallmarks of the amyloid hypothesis in Alzheimer’s disease (AD). Mouse models using APP-transgene overexpression to generate amyloid plaques have shown to model only certain parts of the disease. The extent to which the data from mice can be transferred to man remains controversial. Several studies have shown convincing treatment results in reducing Aβ and enhancing cognition in mice but failed totally in human. One model-dependent factor has so far been almost completely neglected: the endogenous expression of mouse APP and its effects on the transgenic models and the readout for therapeutic approaches. Here, we report that hAPP-transgenic models of …

Oral Monosodium Glutamate Administration Causes Early Onset of Alzheimer's Disease-Like Pathophysiology in APP/PS1 Mice.

2019

Glutamate excitotoxicity has long been related to Alzheimer's disease (AD) pathophysiology, and it has been shown to affect the major AD-related hallmarks, amyloid-β peptide (Aβ) accumulation and tau phosphorylation (p-tau). We investigated whether oral administration of monosodium glutamate (MSG) has effects in a murine model of AD, the double transgenic mice APP/PS1. We found that AD pathogenic factors appear earlier in APP/PS1 when supplemented with MSG, while wildtype mice were essentially not affected. Aβ and p-tau levels were increased in the hippocampus in young APP/PS1 animals upon MSG administration. This was correlated with increased Cdk5-p25 levels. Furthermore, in these mice, we…

Cytoskeletal transgelin 2 contributes to gender-dependent adipose tissue expandability and immune function

2019

During adipogenesis, preadipocytes' cytoskeleton reorganizes in parallel with lipid accumulation. Failure to do so may impact the ability of adipose tissue (AT) to shift between lipid storage and mobilization. Here, we identify cytoskeletal transgelin 2 (TAGLN2) as a protein expressed in AT and associated with obesity and inflammation, being normalized upon weight loss. TAGLN2 was primarily found in the adipose stromovascular cell fraction, but inflammation, TGF-β, and estradiol also prompted increased expression in human adipocytes. Tagln2 knockdown revealed a key functional role, being required for proliferation and differentiation of fat cells, whereas transgenic mice overexpressing Tagl…

Polysialic Acid Acute Depletion Induces Structural Plasticity in Interneurons and Impairs the Excitation/Inhibition Balance in Medial Prefrontal Cort…

2016

The structure and function of the medial prefrontal cortex (mPFC) is affected in several neuropsychiatric disorders, including schizophrenia and major depression. Recent studies suggest that imbalances between excitatory and inhibitory activity (E/I) may be responsible for this cortical dysfunction and, therefore, may underlie the core symptoms of these diseases. This E/I imbalance seems to be correlated with alterations in the plasticity of interneurons but there is still scarce information on the mechanisms that may link these phenomena. The polysialylated form of the neural cell adhesion molecule (PSA-NCAM) is a good candidate, because it modulates the neuronal plasticity of interneurons…

Wnt-Dependent Oligodendroglial-Endothelial Interactions Regulate White Matter Vascularization and Attenuate Injury

2020

Recent studies have indicated oligodendroglial-vascular crosstalk during brain development, but the underlying mechanisms are incompletely understood. We report that oligodendrocyte precursor cells (OPCs) contact sprouting endothelial tip cells in mouse, ferret and human neonatal white matter. Using transgenic mice, we show that increased or decreased OPC density results in cognate changes in white matter vascular investment. Hypoxia promoted both increased OPC numbers and higher white matter vessel density, and endothelial cell expression of the Wnt pathway targets Apcdd1 and Axin2, suggesting paracrine OPC-endothelial signaling. Conditional knockout of OPC Wntless resulted in diminished w…

2017

AbstractWe asked if essentiality for either fertility or viability differentially affects sequence evolution of human testis proteins. Based on murine knockout data, we classified a set of 965 proteins expressed in human seminiferous tubules into three categories: proteins essential for prepubertal survival (“lethality proteins”), associated with male sub- or infertility (“male sub-/infertility proteins”), and nonessential proteins. In our testis protein dataset, lethality genes evolved significantly slower than nonessential and male sub-/infertility genes, which is in line with other authors’ findings. Using tissue specificity, connectivity in the protein-protein interaction (PPI) network,…

Mutations in PRDM15 Are a Novel Cause of Galloway-Mowat Syndrome

2021

Background Galloway-Mowat syndrome (GAMOS) is characterized by neurodevelopmental defects and a progressive nephropathy, which typically manifests as steroid-resistant nephrotic syndrome. The prognosis of GAMOS is poor, and the majority of children progress to renal failure. The discovery of monogenic causes of GAMOS has uncovered molecular pathways involved in the pathogenesis of disease. Methods Homozygosity mapping, whole-exome sequencing, and linkage analysis were used to identify mutations in four families with a GAMOS-like phenotype, and high-throughput PCR technology was applied to 91 individuals with GAMOS and 816 individuals with isolated nephrotic syndrome. In vitro and in vivo st…

m6A modulates neuronal functions and sex determination in Drosophila

2016

N6-methyladenosine RNA (m6A) is a prevalent messenger RNA modification in vertebrates. Although its functions in the regulation of post-transcriptional gene expression are beginning to be unveiled, the precise roles of m6A during development of complex organisms remain unclear. Here we carry out a comprehensive molecular and physiological characterization of the individual components of the methyltransferase complex, as well as of the YTH domain-containing nuclear reader protein in Drosophila melanogaster. We identify the member of the split ends protein family, Spenito, as a novel bona fide subunit of the methyltransferase complex. We further demonstrate important roles of this complex in …

STAG1 mutations cause a novel cohesinopathy characterised by unspecific syndromic intellectual disability

2017

Item does not contain fulltext BACKGROUND: Cohesinopathies are rare neurodevelopmental disorders arising from a dysfunction in the cohesin pathway, which enables chromosome segregation and regulates gene transcription. So far, eight genes from this pathway have been reported in human disease. STAG1 belongs to the STAG subunit of the core cohesin complex, along with five other subunits. This work aimed to identify the phenotype ascribed to STAG1 mutations. METHODS: Among patients referred for intellectual disability (ID) in genetics departments worldwide, array-comparative genomic hybridisation (CGH), gene panel, whole-exome sequencing or whole-genome sequencing were performed following the …

Transcriptional and Epigenetic Control of Astrogliogenesis

2017

Abstract Astrocytes exert pivotal functions in the brain ranging from homeostasis to plasticity and their malfunctioning may contribute to neurodegenerative diseases. With increased recognition of their importance, more efforts are being dedicated to decoding the molecular mechanisms that control the generation of astrocytes from neural stem cells, a process referred to as astrogliogenesis. In this chapter, we highlight the discoveries that have shed light on the role of transcription factors, DNA methylation, histone modifications, and microRNAs in driving the transcriptional programs that underlie astrocyte generation. We further discuss the current understanding of gene regulatory pathwa…