143 research outputs found

    Specific Inhibition of Phosphodiesterase-4B Results in Anxiolysis and Facilitates Memory Acquisition

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    Cognitive dysfunction is a core feature of dementia and a prominent feature in psychiatric disease. As non-redundant regulators of intracellular cAMP gradients, phosphodiesterases (PDE) mediate fundamental aspects of brain function relevant to learning, memory, and higher cognitive functions. Phosphodiesterase-4B (PDE4B) is an important phosphodiesterase in the hippocampal formation, is a major Disrupted in Schizophrenia 1 (DISC1) binding partner and is itself a risk gene for psychiatric illness. To define the effects of specific inhibition of the PDE4B subtype, we generated mice with a catalytic domain mutant form of PDE4B (Y358C) that has decreased ability to hydrolyze cAMP. Structural modelling predictions of decreased function and impaired binding with DISC1 were confirmed in cell assays. Phenotypic characterization of the PDE4BY358C mice revealed facilitated phosphorylation of CREB, decreased binding to DISC1, and upregulation of DISC1 and β-Arrestin in hippocampus and amygdala. In behavioural assays, PDE4BY358C mice displayed decreased anxiety and increased exploration, as well as cognitive enhancement across several tests of learning and memory, consistent with synaptic changes including enhanced long-term potentiation and impaired depotentiation ex vivo. PDE4BY358C mice also demonstrated enhanced neurogenesis. Contextual fear memory, though intact at 24 hours, was decreased at 7 days in PDE4BY358C mice, an effect replicated pharmacologically with a non-selective PDE4 inhibitor, implicating cAMP signalling by PDE4B in a very late phase of consolidation. No effect of the PDE4BY358C mutation was observed in the pre-pulse inhibition and forced swim tests. Our data establish specific inhibition of PDE4B as a promising therapeutic approach for disorders of cognition and anxiety, and a putative target for pathological fear memory

    Reproducibility of molecular phenotypes after long-term differentiation to human iPSC-derived neurons: A multi-site omics study

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    Reproducibility in molecular and cellular studies is fundamental to scientific discovery. To establish the reproducibility of a well-defined long-term neuronal differentiation protocol, we repeated the cellular and molecular comparison of the same two iPSC lines across five distinct laboratories. Despite uncovering acceptable variability within individual laboratories, we detect poor cross-site reproducibility of the differential gene expression signature between these two lines. Factor analysis identifies the laboratory as the largest source of variation along with several variation-inflating confounders such as passaging effects and progenitor storage. Single-cell transcriptomics shows substantial cellular heterogeneity underlying inter-laboratory variability and being responsible for biases in differential gene expression inference. Factor analysis-based normalization of the combined dataset can remove the nuisance technical effects, enabling the execution of robust hypothesis-generating studies. Our study shows that multi-center collaborations can expose systematic biases and identify critical factors to be standardized when publishing novel protocols, contributing to increased cross-site reproducibility

    Neurite Outgrowth Mediated by Translation Elongation Factor eEF1A1: A Target for Antiplatelet Agent Cilostazol

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    Cilostazol, a type-3 phosphodiesterase (PDE3) inhibitor, has become widely used as an antiplatelet drug worldwide. A recent second Cilostazol Stroke Prevention Study demonstrated that cilostazol is superior to aspirin for prevention of stroke after an ischemic stroke. However, its precise mechanisms of action remain to be determined. Here, we report that cilostazol, but not the PDE3 inhibitors cilostamide and milrinone, significantly potentiated nerve growth factor (NGF)-induced neurite outgrowth in PC12 cells. Furthermore, specific inhibitors for the endoplasmic reticulum protein inositol 1,4,5-triphosphate (IP3) receptors and several common signaling pathways (PLC-γ, PI3K, Akt, p38 MAPK, and c-Jun N-terminal kinase (JNK), and the Ras/Raf/ERK/MAPK) significantly blocked the potentiation of NGF-induced neurite outgrowth by cilostazol. Using a proteomics analysis, we identified that levels of eukaryotic translation elongation factor eEF1A1 protein were significantly increased by treatment with cilostazol, but not cilostamide, in PC12 cells. Moreover, the potentiating effects of cilostazol on NGF-induced neurite outgrowth were significantly antagonized by treatment with eEF1A1 RNAi, but not the negative control of eEF1A1. These findings suggest that eEF1A1 and several common cellular signaling pathways might play a role in the mechanism of cilostazol-induced neurite outgrowth. Therefore, agents that can increase the eEF1A1 protein may have therapeutic relevance in diverse conditions with altered neurite outgrowth

    Molecular Imaging in Huntington's Disease

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    Huntington's disease (HD) is a rare monogenic neurodegenerative disorder caused by a trinucleotide CAG repeat expansion in the huntingtin gene resulting in the formation of intranuclear inclusions of mutated huntingtin. The accumulation of mutated huntingtin leads to loss of GABAergic medium spiny neurons (MSNs); subsequently resulting in the development of chorea, cognitive dysfunction and psychiatric symptoms. Premanifest HD gene expansion carriers, provide a unique cohort to examine very early molecular changes, occurring before the development of overt symptoms, to elucidate disease pathophysiology and identify reliable biomarkers of HD progression. Positron emission tomography (PET) is a non-invasive molecular imaging technique allowing the evaluation of specific molecular targets in vivo. Selective PET radioligands provide invaluable tools to investigate the role of the dopaminergic system, brain metabolism, microglial activation, phosphodiesterase 10A, and cannabinoid, GABA, adenosine and opioid receptors in HD. PET has been employed to monitor disease progression aiming to identify a reliable biomarker to predict phenoconversion from premanifest to manifest HD.</p

    LAKOSSÁGI INGATLAN HITELEZÉS

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    Témámnak az ingatlan hitelezést választottam, ezért fontosnak tartom a téma minden lehetséges oldalról való megközelítését. A hitelezés alapjainak bemutatásával az olvasó megtudja milyen bankrendszer található hazánkban, illetve milyen hitel fajtákat kínálnak az ügyfelek részére a pénzintézetek. Manapság nagyon sokféle hitellehetőség áll az ügyfelek rendelkezésére, amik nagyrészét valamilyen módon az állam is támogat. Az új lakás vásárlás vagy építés rengeteg pénzt emésztenek fel, amit a legtöbb fiatal család nem tud azonnal saját forrásból finanszírozni. Ezeknek a családoknak segítenek az államilag támogatott hitelkonstrukciók. Azonban nem szabad elfelejtkezni azokról sem, akik nem tudják, vagy nem akarják kihasználni az államilag támogatott hiteleket. Számukra piaci hitelek állnak rendelkezésre pénzhiányuk kielégítésére. Dolgozatomban leírok minden olyan információt, amelyre szükség lehet egy esetleges hitel felvétele során.Kereskedelem Marketing Felsőoktatási Szakképzésfelsőoktatási szakképzé

    Lakossági ingatlan hitelezés

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    Témámnak az ingatlan hitelezést választottam, ezért fontosnak tartom a téma minden lehetséges oldalról való megközelítését. A hitelezés alapjainak bemutatásával az olvasó megtudja milyen bankrendszer található hazánkban, illetve milyen hitel fajtákat kínálnak az ügyfelek részére a pénzintézetek. Manapság nagyon sokféle hitellehetőség áll az ügyfelek rendelkezésére, amik nagyrészét valamilyen módon az állam is támogat. Az új lakás vásárlás vagy építés rengeteg pénzt emésztenek fel, amit a legtöbb fiatal család nem tud azonnal saját forrásból finanszírozni. Ezeknek a családoknak segítenek az államilag támogatott hitelkonstrukciók. Azonban nem szabad elfelejtkezni azokról sem, akik nem tudják, vagy nem akarják kihasználni az államilag támogatott hiteleket. Számukra piaci hitelek állnak rendelkezésre pénzhiányuk kielégítésére. Dolgozatomban leírok minden olyan információt, amelyre szükség lehet egy esetleges hitel felvétele során.Kereskedelem és marketingfelsőoktatási szakképzé
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