Mechanisms of Manganese-Induced Neurotoxicity in Primary Neuronal Cultures: The Role of Manganese Speciation and Cell Type

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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The role of CpG methylation in cell type-specific expression of the aquaporin-5 gene

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2006.12.126 ◽

2007 ◽

Vol 353 (4) ◽

pp. 1017-1022 ◽

Cited By ~ 17

Author(s):

Johji Nomura ◽

Akinori Hisatsune ◽

Takeshi Miyata ◽

Yoichiro Isohama

Keyword(s):

Cpg Methylation ◽

Cell Type ◽

Aquaporin 5 ◽

Specific Expression ◽

Cell Type Specific Expression ◽

Cell Type Specific

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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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Differential Role of Basal Keratinocytes in UV-Induced Immunosuppression and Skin Cancer

Molecular and Cellular Biology ◽

10.1128/mcb.00807-06 ◽

2006 ◽

Vol 26 (22) ◽

pp. 8515-8526 ◽

Cited By ~ 32

Author(s):

Judith Jans ◽

George A. Garinis ◽

Wouter Schul ◽

Adri van Oudenaren ◽

Michael Moorhouse ◽

...

Keyword(s):

Skin Cancer ◽

Biological Effects ◽

Mouse Skin ◽

Cell Type ◽

Cell Type Specificity ◽

Basal Keratinocytes ◽

Expression Of Genes ◽

Pyrimidine Dimers ◽

Response To Stress

ABSTRACT Cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts (6-4PPs) comprise major UV-induced photolesions. If left unrepaired, these lesions can induce mutations and skin cancer, which is facilitated by UV-induced immunosuppression. Yet the contribution of lesion and cell type specificity to the harmful biological effects of UV exposure remains currently unclear. Using a series of photolyase-transgenic mice to ubiquitously remove either CPDs or 6-4PPs from all cells in the mouse skin or selectively from basal keratinocytes, we show that the majority of UV-induced acute effects to require the presence of CPDs in basal keratinocytes in the mouse skin. At the fundamental level of gene expression, CPDs induce the expression of genes associated with repair and recombinational processing of DNA damage, as well as apoptosis and a response to stress. At the organismal level, photolyase-mediated removal of CPDs, but not 6-4PPs, from the genome of only basal keratinocytes substantially diminishes the incidence of skin tumors; however, it does not affect the UVB-mediated immunosuppression. Taken together, these findings reveal a differential role of basal keratinocytes in these processes, providing novel insights into the skin's acute and chronic responses to UV in a lesion- and cell-type-specific manner.

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