Seizure-like activity leads to the release of BAD from 14-3-3 protein and cell death in hippocampal neurons in vitro

Abstract Background: Anesthetic neurotoxicity in the developing brain of rodents and primates has raised concern. Xenon may be a nonneurotoxic alternative to halogenated anesthetics, but its toxicity has only been studied at low concentrations, where neuroprotective effects predominate in animal models. An equipotent comparison of xenon and halogenated anesthetics with respect to neurotoxicity in developing neurons has not been made. Methods: Organotypic hippocampal cultures from 7-day-old rats were exposed to 0.75, 1, and 2 minimum alveolar concentrations (MAC) partial pressures (60% xenon at 1.2, 2.67, and 3.67 atm; isoflurane at 1.4, 1.9, and 3.8%; and sevoflurane at 3.4 and 6.8%) for 6 h, at atmospheric pressure or in a pressure chamber. Cell death was assessed 24 h later with fluorojade and fluorescent dye exclusion techniques. Results: Xenon caused death of hippocampal neurons in CA1, CA3, and dentate regions after 1 and 2 MAC exposures, but not at 0.75 MAC. At 1 MAC, xenon increased cell death 40% above baseline (P < 0.01; ANOVA with Dunnett test). Both isoflurane and sevoflurane increased neuron death at 1 but not 2 MAC. At 1 MAC, the increase in cell death compared with controls was 63% with isoflurane and 90% with sevoflurane (both P < 0.001). Pretreatment of cultures with isoflurane (0.75 MAC) reduced neuron death after 1 MAC xenon, isoflurane, and sevoflurane. Conclusion: Xenon causes neuronal cell death in an in vitro model of the developing rodent brain at 1 MAC, as does isoflurane and sevoflurane at similarly potent concentrations. Preconditioning with a subtoxic dose of isoflurane eliminates this toxicity.

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Remodeling of Intracellular Ca2+ Homeostasis in Rat Hippocampal Neurons Aged In Vitro

International Journal of Molecular Sciences ◽

10.3390/ijms21041549 ◽

2020 ◽

Vol 21 (4) ◽

pp. 1549 ◽

Cited By ~ 5

Author(s):

Maria Calvo-Rodriguez ◽

Elena Hernando-Pérez ◽

Sara López-Vázquez ◽

Javier Núñez ◽

Carlos Villalobos ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Cell Death ◽

Neurodegenerative Disorders ◽

Hippocampal Neurons ◽

Molecular Mechanisms ◽

Neuronal Damage ◽

Amyloid Β ◽

Memory Storage ◽

Amyloid Β Peptide

Aging is often associated with a cognitive decline and a susceptibility to neuronal damage. It is also the most important risk factor for neurodegenerative disorders, particularly Alzheimer’s disease (AD). AD is related to an excess of neurotoxic oligomers of amyloid β peptide (Aβo); however, the molecular mechanisms are still highly controversial. Intracellular Ca2+ homeostasis plays an important role in the control of neuronal activity, including neurotransmitter release, synaptic plasticity, and memory storage, as well as neuron cell death. Recent evidence indicates that long-term cultures of rat hippocampal neurons, resembling aged neurons, undergo cell death after treatment with Aβo, whereas short-term cultures, resembling young neurons, do not. These in vitro changes are associated with the remodeling of intracellular Ca2+ homeostasis with aging, thus providing a simplistic model for investigating Ca2+ remodeling in aging. In vitro aged neurons show increased resting cytosolic Ca2+ concentration, enhanced Ca2+ store content, and Ca2+ release from the endoplasmic reticulum (ER). Ca2+ transfer from the endoplasmic reticulum (ER) to mitochondria is also enhanced. Aged neurons also show decreased store-operated Ca2+ entry (SOCE), a Ca2+ entry pathway related to memory storage. At the molecular level, in vitro remodeling is associated with changes in the expression of Ca2+ channels resembling in vivo aging, including changes in N-methyl-D-aspartate NMDA receptor and inositol 1,4,5-trisphosphate (IP3) receptor isoforms, increased expression of the mitochondrial calcium uniporter (MCU), and decreased expression of Orai1/Stim1, the molecular players involved in SOCE. Additionally, Aβo treatment exacerbates most of the changes observed in aged neurons and enhances susceptibility to cell death. Conversely, the solely effect of Aβo in young neurons is to increase ER–mitochondria colocalization and enhance Ca2+ transfer from ER to mitochondria without inducing neuronal damage. We propose that cultured rat hippocampal neurons may be a useful model to investigate Ca2+ remodeling in aging and in age-related neurodegenerative disorders.

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Neurotoxicity Mediated by Aberrant Patterns of Synaptic Activity Between Rat Hippocampal Neurons in Culture

Journal of Neurophysiology ◽

10.1152/jn.1998.80.5.2688 ◽

1998 ◽

Vol 80 (5) ◽

pp. 2688-2698 ◽

Cited By ~ 24

Author(s):

John R. McLeod ◽

Maoxing Shen ◽

Daniel J. Kim ◽

Stanley A. Thayer

Keyword(s):

Cell Death ◽

Nmda Receptor ◽

Receptor Antagonist ◽

Hippocampal Neurons ◽

Cell Voltage ◽

Nmda Receptor Antagonist ◽

Synaptic Activity ◽

Slow Inward Current ◽

Inward Current

McLeod, John R., Jr., Maoxing Shen, Daniel J. Kim, and Stanley A. Thayer. Neurotoxicity mediated by aberrant patterns of synaptic activity between rat hippocampal neurons in culture. J. Neurophysiol. 80: 2688–2698, 1998. Reducing the extracellular Mg2+ concentration ([Mg2+]o) to 0.1 mM evoked an aberrant pattern of glutamatergic activity in the synaptic network formed by rat hippocampal neurons grown in primary culture. This treatment resulted in a significant increase in neuronal death when maintained for 20–24 h; 0.1 mM [Mg2+]o elicited a stable and repetitive series of intracellular Ca2+ concentration ([Ca2+]i) spikes as indicated by indo-1-based microfluorimetry. Fura-2-based digital imaging experiments found that the [Ca2+]i spikes were synchronized for all the neurons in a given field. Thus electrophysiological recordings from individual cells were reasonable representations of the field as a whole, enabling correlation of electrical activity to viability. Underlying each [Ca2+]i spike was an intense burst of action potentials. Whole cell voltage-clamp experiments showed that a burst was composed of fast action currents superimposed on a slow inward current. The N-methyl-d-aspartate (NMDA) receptor antagonist CGS19755 (10 μM) blocked [Ca2+]i spiking, the slow inward current, and the cell death induced by low [Mg2+]o. The L-type Ca2+ channel antagonist nimodipine (10 μM) blocked [Ca2+]i spiking, all synaptic activity, and the cell death induced by low [Mg2+]o. The non-NMDA receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 10 μM) exerted variable effects on [Ca2+]i spiking and blocked the slow inward current only when the cells were held at a relatively negative holding potential. CNQX did not afford any protection from 0.1 mM [Mg2+]o-induced neurotoxicity. [Ca2+]i imaging experiments showed that CNQX inhibited [Ca2+]i spiking in a subset of neurons within an active network. Thus, the neurons that were insensitive to CNQX appear to be those that were destined to die. We characterized an in vitro model that allowed us to correlate specific electrophysiological components of glutamatergic synaptic activity to the subsequent viability of the network. A slow NMDA receptor-mediated inward current was required to elicit [Ca2+]i spiking and neurotoxicity. Non-NMDA receptors did not contribute to synaptically mediated cell death in this model. An L-type Ca2+ channel antagonist was neuroprotective when used at concentrations that blocked synaptic activity, suggesting that dendritic L-type Ca2+ channels present a useful target for neuroprotective drugs.

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In vitro Model of Hypoxia: Basic Fibroblast Growth Factor Can Rescue Cultured CNS Neurons from Oxygen-Deprived Cell Death

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1993.130 ◽

1993 ◽

Vol 13 (6) ◽

pp. 1029-1032 ◽

Cited By ~ 27

Author(s):

Yukio Akaneya ◽

Yasushi Enokido ◽

Mitsuo Takahashi ◽

Hiroshi Hatanaka

Keyword(s):

Cell Death ◽

Growth Factor ◽

Fibroblast Growth Factor ◽

Basic Fibroblast Growth Factor ◽

Hippocampal Neurons ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Dependent Manner ◽

Fibroblast Growth

We established an in vitro hypoxia model and investigated the protective effect of basic fibroblast growth factor (bFGF) against neuronal cell death caused by hypoxia. Hippocampal neurons obtained from rats on embryonic day (E) 17 and 20 and on postnatal day (P) 4 were cultured for 6–24 h in an oxygen-deprived state. This in vitro hypoxia study showed that the cultured neurons were sensitive to the oxygen deprivation. The cultured P4 rat hippocampal neurons seemed to be weaker in the hypoxia condition than those of E17 and E20 rats, suggesting that the cultured postnatal cells might be sensitive to hypoxia. bFGF, but not nerve growth factor, prevented the neuronal cell death caused by hypoxia in a dose-dependent manner.

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In vitro status epilepticus but not spontaneous recurrent seizures cause cell death in cultured hippocampal neurons

Epilepsy Research ◽

10.1016/j.eplepsyres.2007.05.011 ◽

2007 ◽

Vol 75 (2-3) ◽

pp. 171-179 ◽

Cited By ~ 19

Author(s):

Laxmikant S. Deshpande ◽

Jeffrey K. Lou ◽

Ali Mian ◽

Robert E. Blair ◽

Sompong Sombati ◽

...

Keyword(s):

Cell Death ◽

Status Epilepticus ◽

Hippocampal Neurons ◽

Spontaneous Recurrent Seizures ◽

Cultured Hippocampal Neurons

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The P-MAPA immunomodulator partially prevents apoptosis induced by Zika virus infection in THP-1 cells

Current Pharmaceutical Biotechnology ◽

10.2174/1389201021666200602140005 ◽

2020 ◽

Vol 21 ◽

Cited By ~ 1

Author(s):

Morganna C. Lima ◽

Elisa A. N. Azevedo ◽

Clarice N. L. de Morais ◽

Larissa I. O. de Sousa ◽

Bruno M. Carvalho ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Death ◽

Virus Infection ◽

Virus Replication ◽

Zika Virus ◽

Mammalian Cells ◽

Caspase 3 ◽

Neurological Complications ◽

Zika Virus Infection

Background: Zika virus is an emerging arbovirus of global importance. ZIKV infection is associated with a range of neurological complications such as the Congenital Zika Syndrome and Guillain Barré Syndrome. Despite the magnitude of recent outbreaks, there is no specific therapy to prevent or to alleviate disease pathology. Objective: To investigate the role of P-MAPA immunomodulator in Zika-infected THP-1 cells. Methods: THP-1 cells were subjected at Zika virus infection (Multiplicity of Infection = 0.5) followed by treatment with P-MAPA for until 96 hours post-infection. After that, the cell death was analyzed by annexin+/ PI+ and caspase 3/ 7+ staining by flow cytometry. In addition, the virus replication and cell proliferation were accessed by RT-qPCR and Ki67 staining, respectively. Results: We demonstrate that P-MAPA in vitro treatment significantly reduces Zika virus-induced cell death and caspase-3/7 activation on THP-1 infected cells, albeit it has no role in virus replication and cell proliferation. Conclusions: Our study reveals that P-MAPA seems to be a satisfactory alternative to inhibits the effects of Zika virus infection in mammalian cells.

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Stew in its Own Juice: Protein Homeostasis Machinery Inhibition Reduces Cell Viability in Multiple Myeloma Cell Lines

Current Molecular Medicine ◽

10.2174/1566524019666190305134441 ◽

2019 ◽

Vol 19 (2) ◽

pp. 112-119 ◽

Cited By ~ 1

Author(s):

Mariana B. de Oliveira ◽

Luiz F.G. Sanson ◽

Angela I.P. Eugenio ◽

Rebecca S.S. Barbosa-Dantas ◽

Gisele W.B. Colleoni

Keyword(s):

Multiple Myeloma ◽

Cell Death ◽

Cell Viability ◽

Cell Lines ◽

Treatment Options ◽

Compensatory Mechanism ◽

Protein Homeostasis ◽

Protein Response ◽

Rpmi 8226

Introduction:Multiple myeloma (MM) cells accumulate in the bone marrow and produce enormous quantities of immunoglobulins, causing endoplasmatic reticulum stress and activation of protein handling machinery, such as heat shock protein response, autophagy and unfolded protein response (UPR).Methods:We evaluated cell lines viability after treatment with bortezomib (B) in combination with HSP70 (VER-15508) and autophagy (SBI-0206965) or UPR (STF- 083010) inhibitors.Results:For RPMI-8226, after 72 hours of treatment with B+VER+STF or B+VER+SBI, we observed 15% of viable cells, but treatment with B alone was better (90% of cell death). For U266, treatment with B+VER+STF or with B+VER+SBI for 72 hours resulted in 20% of cell viability and both treatments were better than treatment with B alone (40% of cell death). After both triplet combinations, RPMI-8226 and U266 presented the overexpression of XBP-1 UPR protein, suggesting that it is acting as a compensatory mechanism, in an attempt of the cell to handle the otherwise lethal large amount of immunoglobulin overload.Conclusion:Our in vitro results provide additional evidence that combinations of protein homeostasis inhibitors might be explored as treatment options for MM.

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Astrocytic Expression of the Immunoreceptor CD300f Protects Hippocampal Neurons from Amyloid-β Oligomer Toxicity In Vitro

Current Alzheimer Research ◽

10.2174/1567205014666170202121709 ◽

2017 ◽

Vol 14 (7) ◽

Cited By ~ 1

Author(s):

Thiago Zaqueu Lima ◽

Luis Roberto Sardinha ◽

Joan Sayos ◽

Luiz Eugenio Mello ◽

Hugo Peluffo

Keyword(s):

Hippocampal Neurons ◽

Amyloid Β ◽

Toxicity In Vitro

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Computational and In-Vitro Validation of Natural Molecules as Potential Acetylcholinesterase Inhibitors and Neuroprotective Agents

Current Alzheimer Research ◽

10.2174/1567205016666181212155147 ◽

2019 ◽

Vol 16 (2) ◽

pp. 116-127 ◽

Cited By ~ 2

Author(s):

Ashwani Kumar ◽

Vineet Mehta ◽

Utkarsh Raj ◽

Pritish Kumar Varadwaj ◽

Malairaman Udayabanu ◽

...

Keyword(s):

In Silico ◽

Hippocampal Neurons ◽

Symptomatic Relief ◽

In Vitro Assays ◽

Disease Modifying Drugs ◽

In Silico Docking ◽

Ache Inhibitors ◽

Significant Difference ◽

Disease Modifying

Background: Cholinesterase inhibitors are the first line of therapy for the management of Alzheimer’s disease (AD), however, it is now established that they provide only temporary and symptomatic relief, besides, having several inherited side-effects. Therefore, an alternative drug discovery method is used to identify new and safer ‘disease-modifying drugs’. Methods: Herein, we screened 646 small molecules of natural origin having reported pharmacological and functional values through in-silico docking studies to predict safer neuromodulatory molecules with potential to modulate acetylcholine metabolism. Further, the potential of the predicted molecules to inhibit acetylcholinesterase (AChE) activity and their ability to protect neurons from degeneration was determined through in-vitro assays. Results: Based on in-silico AChE interaction studies, we predicted quercetin, caffeine, ascorbic acid and gallic acid to be potential AChE inhibitors. We confirmed the AChE inhibitory potential of these molecules through in-vitro AChE inhibition assay and compared results with donepezil and begacestat. Herbal molecules significantly inhibited enzyme activity and inhibition for quercetin and caffeine did not show any significant difference from donepezil. Further, the tested molecules did not show any neurotoxicity against primary (E18) hippocampal neurons. We observed that quercetin and caffeine significantly improved neuronal survival and efficiently protected hippocampal neurons from HgCl2 induced neurodegeneration, which other molecules, including donepezil and begacestat, failed to do. Conclusion: Quercetin and caffeine have the potential as “disease-modifying drugs” and may find application in the management of neurological disorders such as AD.

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Single-chain Antibody Against Reg4 Suppresses Gastric Cancer Cell Growth and Enhances 5-FU-induced Cell Death in vitro

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520619666181122104720 ◽

2019 ◽

Vol 19 (5) ◽

pp. 610-619 ◽

Cited By ~ 3

Author(s):

Xue-Qing Zhang ◽

Lu-Ting Yu ◽

Pei Du ◽

Tian-Qi Yin ◽

Zhi-Yuan Zhang ◽

...

Keyword(s):

Gastric Cancer ◽

Cell Proliferation ◽

Cell Death ◽

Cancer Cell ◽

Gastric Cancer Cell ◽

Single Chain ◽

Single Chain Antibody ◽

Ags Cells ◽

Thiazolyl Blue Tetrazolium Bromide

Background:Regenerating islet-derived gene family member 4 (Reg4), a well-investigated growth factor in the regenerative pancreas, has recently been reported to be highly associated with a majority of gastrointestinal cancers. Pathological hyper-expression or artificial over-expression of Reg4 causes acceleration of tumor growth, migration, and resistance to chemotherapeutic 5-Fluorouracil (5-FU). Until now, no method has been successfully established for eliminating the effects of Reg4 protein.Methods:This study reports the production of an engineered immunoglobin, a single-chain variable fragment (scFv-Reg4), to specifically bind Reg4 and block the bioactivity. The complementary-determining regions (CDRs) against Reg4 were assigned using MOE and ZDOCK servers. The binding affinity (KD) was determined by bio-layer interferometry (BLI). MKN45 and AGS cell proliferation was determined by Thiazolyl blue tetrazolium bromide (MTT) method and the cell apoptosis was detected by flow cytometry assay.Results:The KD of scFv-Reg4 to Reg4 was determined to be 1.91×10-8. In MKN45 and AGS cell lines, scFv- Reg4 depressed Reg4-stimulated cell proliferation and the inhibitory rates were 27.7±1.5% and 17.3±2.6%, respectively. Furthermore, scFv significantly enhanced 5-FU-induced cell death, from 23.0±1.0% to 28.4±1.2% in MKN45 and 28.2±0.7% to 36.6±0.6% in AGS cells. Treatment with scFv alone could lyse cancer cells to a certain extent, but no significance has been observed.Conclusion:The single-chain antibody (scFv-Reg4) significantly inhibited gastric cancer cell proliferation and synergistically enhanced the lethal effect of 5-FU. Thus, traditional chemo-/radio- therapeutics supplemented with scFv-Reg4 may provide advances in the strategy for gastrointestinal cancer treatment.

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