Role of Ca2+ in α-Amino-3-Hydroxy-5-Methyl-4-Isoxazolepropionic Acid-Mediated Polyphosphoinositide Turnover in Primary Neuronal Cultures

Tau protein is largely responsible for tauopathies, including Alzheimer’s disease (AD), where it accumulates in the brain as insoluble aggregates. Tau mRNA is regulated by alternative splicing, and inclusion or exclusion of exon 10 gives rise to the 3R and 4R isoforms respectively, whose balance is physiologically regulated. In this sense, one of the several factors that regulate alternative splicing of tau is GSK3β, whose activity is inhibited by the cellular prion protein (PrPC), which has different physiological functions in neuroprotection and neuronal differentiation. Moreover, a relationship between PrPC and tau expression levels has been reported during AD evolution. For this reason, in this study we aimed to analyze the role of PrPC and the implication of GSK3β in the regulation of tau exon 10 alternative splicing. We used AD human samples and mouse models of PrPC ablation and tau overexpression. In addition, we used primary neuronal cultures to develop functional studies. Our results revealed a paralleled association between PrPC expression and tau 4R isoforms in all models analyzed. In this sense, reduction or ablation of PrPC levels induces an increase in tau 3R/4R balance. More relevantly, our data points to GSK3β activity downstream from PrPC in this phenomenon. Our results indicate that PrPC plays a role in tau exon 10 inclusion through the inhibitory capacity of GSK3β.

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Validation of long-term primary neuronal cultures and network activity through the integration of reversibly bonded microbioreactors and MEA substrates

Biotechnology and Bioengineering ◽

10.1002/bit.23310 ◽

2011 ◽

Vol 109 (1) ◽

pp. 166-175 ◽

Cited By ~ 16

Author(s):

Emilia Biffi ◽

Andrea Menegon ◽

Francesco Piraino ◽

Alessandra Pedrocchi ◽

Gianfranco B. Fiore ◽

...

Keyword(s):

Network Activity ◽

Neuronal Cultures ◽

Primary Neuronal Cultures

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Difluoroboron β-diketonate polylactic acid oxygen nanosensors for intracellular neuronal imaging

Scientific Reports ◽

10.1038/s41598-020-80172-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Meng Zhuang ◽

Suchitra Joshi ◽

Huayu Sun ◽

Tamal Batabyal ◽

Cassandra L. Fraser ◽

...

Keyword(s):

Neuronal Activity ◽

Oxygen Sensing ◽

Brain Slices ◽

Neuronal Cell ◽

Quantum Yields ◽

Poly Lactic Acid ◽

Neuronal Cultures ◽

Primary Neuronal Cultures ◽

Non Invasive ◽

Mitotracker Red

AbstractCritical for metabolism, oxygen plays an essential role in maintaining the structure and function of neurons. Oxygen sensing is important in common neurological disorders such as strokes, seizures, or neonatal hypoxic–ischemic injuries, which result from an imbalance between metabolic demand and oxygen supply. Phosphorescence quenching by oxygen provides a non-invasive optical method to measure oxygen levels within cells and tissues. Difluoroboron β-diketonates are a family of luminophores with high quantum yields and tunable fluorescence and phosphorescence when embedded in certain rigid matrices such as poly (lactic acid) (PLA). Boron nanoparticles (BNPs) can be fabricated from dye-PLA materials for oxygen mapping in a variety of biological milieu. These dual-emissive nanoparticles have oxygen-insensitive fluorescence, oxygen-sensitive phosphorescence, and rigid matrix all in one, enabling real-time ratiometric oxygen sensing at micron-level spatial and millisecond-level temporal resolution. In this study, BNPs are applied in mouse brain slices to investigate oxygen distributions and neuronal activity. The optical properties and physical stability of BNPs in a biologically relevant buffer were stable. Primary neuronal cultures were labeled by BNPs and the mitochondria membrane probe MitoTracker Red FM. BNPs were taken up by neuronal cell bodies, at dendrites, and at synapses, and the localization of BNPs was consistent with that of MitoTracker Red FM. The brain slices were stained with the BNPs, and the BNPs did not significantly affect the electrophysiological properties of neurons. Oxygen maps were generated in living brain slices where oxygen is found to be mostly consumed by mitochondria near synapses. Finally, the BNPs exhibited excellent response when the conditions varied from normoxic to hypoxic and when the neuronal activity was increased by increasing K+ concentration. This work demonstrates the capability of BNPs as a non-invasive tool in oxygen sensing and could provide fundamental insight into neuronal mechanisms and excitability research.

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Oxidative Stress Induces Dephosphorylation of τ in Rat Brain Primary Neuronal Cultures

Journal of Neurochemistry ◽

10.1046/j.1471-4159.1997.68041590.x ◽

2002 ◽

Vol 68 (4) ◽

pp. 1590-1597 ◽

Cited By ~ 30

Author(s):

Daniel R. Davis ◽

Brian H. Anderton ◽

Jean-Pierre Brion ◽

C. Hugh Reynolds ◽

Diane P. Hanger

Keyword(s):

Oxidative Stress ◽

Rat Brain ◽

Neuronal Cultures ◽

Primary Neuronal Cultures

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Ketamine decreases neuronally released glutamate via retrograde stimulation of presynaptic adenosine A1 receptors

Molecular Psychiatry ◽

10.1038/s41380-021-01246-3 ◽

2021 ◽

Author(s):

Vesna Lazarevic ◽

Yunting Yang ◽

Ivana Flais ◽

Per Svenningsson

Keyword(s):

Cortical Neurons ◽

Intracellular Signaling ◽

Ex Vivo ◽

Forced Swim Test ◽

Glutamate Release ◽

Neuronal Cultures ◽

Extracellular Glutamate ◽

Primary Neuronal Cultures ◽

Adenosine A1 Receptors ◽

Adenosine A1

AbstractKetamine produces a rapid antidepressant response in patients with major depressive disorder (MDD), but the underlying mechanisms appear multifaceted. One hypothesis, proposes that by antagonizing NMDA receptors on GABAergic interneurons, ketamine disinhibits afferens to glutamatergic principal neurons and increases extracellular glutamate levels. However, ketamine seems also to reduce rapid glutamate release at some synapses. Therefore, clinical studies in MDD patients have stressed the need to identify mechanisms whereby ketamine decreases presynaptic activity and glutamate release. In the present study, the effect of ketamine and its antidepressant metabolite, (2R,6R)-HNK, on neuronally derived glutamate release was examined in rodents. We used FAST methodology to measure depolarization-evoked extracellular glutamate levels in vivo in freely moving or anesthetized animals, synaptosomes to detect synaptic recycling ex vivo and primary cortical neurons to perform functional imaging and to examine intracellular signaling in vitro. In all these versatile approaches, ketamine and (2R,6R)-HNK reduced glutamate release in a manner which could be blocked by AMPA receptor antagonism. Antagonism of adenosine A1 receptors, which are almost exclusively expressed at nerve terminals, also counteracted ketamine’s effect on glutamate release and presynaptic activity. Signal transduction studies in primary neuronal cultures demonstrated that ketamine reduced P-T286-CamKII and P-S9-Synapsin, which correlated with decreased synaptic vesicle recycling. Moreover, systemic administration of A1R antagonist counteracted the antidepressant-like actions of ketamine and (2R,6R)-HNK in the forced swim test. To conclude, by studying neuronally released glutamate, we identified a novel retrograde adenosinergic feedback mechanism that mediate inhibitory actions of ketamine on glutamate release that may contribute to its rapid antidepressant action.

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Regulation of Cholesterol Homeostasis by the Liver X Receptors in the Central Nervous System

Molecular Endocrinology ◽

10.1210/mend.16.6.0835 ◽

2002 ◽

Vol 16 (6) ◽

pp. 1378-1385 ◽

Cited By ~ 78

Author(s):

Karl D. Whitney ◽

Michael A. Watson ◽

Jon L. Collins ◽

William G. Benson ◽

Tammy M. Stone ◽

...

Keyword(s):

Gene Expression ◽

Central Nervous System ◽

Nervous System ◽

Cholesterol Efflux ◽

Target Genes ◽

Cholesterol Homeostasis ◽

Neuronal Cultures ◽

Primary Neuronal Cultures ◽

The Central Nervous System ◽

Lxr Agonists

Abstract The nuclear oxysterol receptors liver X receptor-α [LXRα (NR1H3)] and LXRβ (NR1H2) coordinately regulate genes involved in cholesterol homeostasis. Although both LXR subtypes are expressed in the brain, their roles in this tissue remain largely unexplored. In this report, we show that LXR agonists have marked effects on gene expression in murine brain tissue both in vitro and in vivo. In primary astrocyte cultures, LXR agonists regulated several established LXR target genes, including ATP binding cassette transporter A1, and enhanced cholesterol efflux. In contrast, little or no effect on gene expression or cholesterol efflux was detected in primary neuronal cultures. Treatment of mice with a selective LXR agonist resulted in the induction of several LXR target genes related to cholesterol homeostasis in the cerebellum and hippocampus. These data provide the first evidence that the LXRs regulate cholesterol homeostasis in the central nervous system. Because dysregulation of cholesterol balance is implicated in central nervous system diseases such as Alzheimer’s and Niemann-Pick disease, pharmacological manipulation of the LXRs may prove beneficial in the treatment of these disorders.

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Medicinal Leech CNS as a Model for Exosome Studies in the Crosstalk between Microglia and Neurons

International Journal of Molecular Sciences ◽

10.3390/ijms19124124 ◽

2018 ◽

Vol 19 (12) ◽

pp. 4124 ◽

Cited By ~ 6

Author(s):

Antonella Raffo-Romero ◽

Tanina Arab ◽

Issa Al-Amri ◽

Francoise Le Marrec-Croq ◽

Christelle Van Camp ◽

...

Keyword(s):

Transforming Growth Factor Beta ◽

Transforming Growth Factor ◽

Ex Vivo ◽

Present Report ◽

Primary Cultures ◽

Cell Communication ◽

Medicinal Leech ◽

Neuronal Cultures ◽

Primary Neuronal Cultures ◽

A Cell

In healthy or pathological brains, the neuroinflammatory state is supported by a strong communication involving microglia and neurons. Recent studies indicate that extracellular vesicles (EVs), including exosomes and microvesicles, play a key role in the physiological interactions between cells allowing central nervous system (CNS) development and/or integrity. The present report used medicinal leech CNS to investigate microglia/neuron crosstalk from ex vivo approaches as well as primary cultures. The results demonstrated a large production of exosomes from microglia. Their incubation to primary neuronal cultures showed a strong interaction with neurites. In addition, neurite outgrowth assays demonstrated microglia exosomes to exhibit significant neurotrophic activities using at least a Transforming Growth Factor beta (TGF-β) family member, called nGDF (nervous Growth/Differentiation Factor). Of interest, the results also showed an EV-mediated dialog between leech microglia and rat cells highlighting this communication to be more a matter of molecules than of species. Taken together, the present report brings a new insight into the microglia/neuron crosstalk in CNS and would help deciphering the molecular evolution of such a cell communication in brain.

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