Isoflavones Induce BEX2-Dependent Autophagy to Prevent ATR-Induced Neurotoxicity in SH-SY5Y Cells

Background/Aims: Atrazine (ATR) is a broad-spectrum herbicide in wide use around the world. However, ATR is neurotoxic and can cause cell death in dopaminergic neurons, leading to neurodegenerative disorders. Autophagy is the basic cellular catabolic process involving the degradation of proteins and damaged organelles. Studies have shown that certain plant compounds can induce autophagy and prevent neuronal cell death. This prompted us to investigate plant compounds that might reduce the neurotoxic effects of ATR. Methods: By CCK-8 and flow cytometry, we tested the ability of five candidate compounds—isoflavones, resveratrol, quercetin, curcumin, and green tea polyphenols—to protect cells from ATR. Changes in the expression of tyrosine hydroxylase (TH) and brain-expressed X-linked 2 (BEX2), autophagy-related proteins and key factors in mTOR signaling, were detected by Western blotting. Results: Isoflavones had the strongest activity against ATR-induced neuronal apoptosis. ATR reduced the expression of TH and BEX2, whereas isoflavones increased TH and BEX2 expression. In addition, ATR inhibited autophagy, whereas isoflavones induced autophagy through the accumulation of LC3-II and decreased expression of p62; this effect was abolished by 3-methyladenine (3-MA). Furthermore, BEX2 siRNA abolished isoflavone-mediated autophagy and neuroprotection in vitro. Conclusion: Isoflavones activate BEX2-dependent autophagy, protecting against ATR-induced neuronal apoptosis.

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Cytokinin Plant Hormones Have Neuroprotective Activity in In Vitro Models of Parkinson’s Disease

Molecules ◽

10.3390/molecules26020361 ◽

2021 ◽

Vol 26 (2) ◽

pp. 361

Author(s):

Gabriel Gonzalez ◽

Jiří Grúz ◽

Cosimo Walter D’Acunto ◽

Petr Kaňovský ◽

Miroslav Strnad

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Cell Death ◽

Neuronal Cell Death ◽

Disease Model ◽

Neuronal Cell ◽

Zeatin Riboside ◽

Neuroprotective Activity ◽

Protective Activity

Cytokinins are adenine-based phytohormones that regulate key processes in plants, such as cell division and differentiation, root and shoot growth, apical dominance, branching, and seed germination. In preliminary studies, they have also shown protective activities against human neurodegenerative diseases. To extend knowledge of the protection (protective activity) they offer, we investigated activities of natural cytokinins against salsolinol (SAL)-induced toxicity (a Parkinson’s disease model) and glutamate (Glu)-induced death of neuron-like dopaminergic SH-SY5Y cells. We found that kinetin-3-glucoside, cis-zeatin riboside, and N6-isopentenyladenosine were active in the SAL-induced PD model. In addition, trans-, cis-zeatin, and kinetin along with the iron chelator deferoxamine (DFO) and the necroptosis inhibitor necrostatin 1 (NEC-1) significantly reduced cell death rates in the Glu-induced model. Lactate dehydrogenase assays revealed that the cytokinins provided lower neuroprotective activity than DFO and NEC-1. Moreover, they reduced apoptotic caspase-3/7 activities less strongly than DFO. However, the cytokinins had very similar effects to DFO and NEC-1 on superoxide radical production. Overall, they showed protective activity in the SAL-induced model of parkinsonian neuronal cell death and Glu-induced model of oxidative damage mainly by reduction of oxidative stress.

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Mesenchymal Stem Cells (MSCs) Coculture Protects [Ca2+]i Orchestrated Oxidant Mediated Damage in Differentiated Neurons In Vitro

Cells ◽

10.3390/cells7120250 ◽

2018 ◽

Vol 7 (12) ◽

pp. 250 ◽

Cited By ~ 9

Author(s):

Adel Alhazzani ◽

Prasanna Rajagopalan ◽

Zaher Albarqi ◽

Anantharam Devaraj ◽

Mohamed Hessian Mohamed ◽

...

Keyword(s):

Cell Death ◽

Transforming Growth Factor ◽

Neuronal Cells ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Apoptotic Cells ◽

Sequence Of Events ◽

Cox 2 ◽

Anti Inflammatory

Cell-therapy modalities using mesenchymal stem (MSCs) in experimental strokes are being investigated due to the role of MSCs in neuroprotection and regeneration. It is necessary to know the sequence of events that occur during stress and how MSCs complement the rescue of neuronal cell death mediated by [Ca2+]i and reactive oxygen species (ROS). In the current study, SH-SY5Y-differentiated neuronal cells were subjected to in vitro cerebral ischemia-like stress and were experimentally rescued from cell death using an MSCs/neuronal cell coculture model. Neuronal cell death was characterized by the induction of proinflammatory tumor necrosis factor (TNF)-α, interleukin (IL)-1β and -12, up to 35-fold with corresponding downregulation of anti-inflammatory cytokine transforming growth factor (TGF)-β, IL-6 and -10 by approximately 1 to 7 fold. Increased intracellular calcium [Ca2+]i and ROS clearly reaffirmed oxidative stress-mediated apoptosis, while upregulation of nuclear factor NF-B and cyclo-oxygenase (COX)-2 expressions, along with ~41% accumulation of early and late phase apoptotic cells, confirmed ischemic stress-mediated cell death. Stressed neuronal cells were rescued from death when cocultured with MSCs via increased expression of anti-inflammatory cytokines (TGF-β, 17%; IL-6, 4%; and IL-10, 13%), significantly downregulated NF-B and proinflammatory COX-2 expression. Further accumulation of early and late apoptotic cells was diminished to 23%, while corresponding cell death decreased from 40% to 17%. Low superoxide dismutase 1 (SOD1) expression at the mRNA level was rescued by MSCs coculture, while no significant changes were observed with catalase (CAT) and glutathione peroxidase (GPx). Interestingly, increased serotonin release into the culture supernatant was proportionate to the elevated [Ca2+]i and corresponding ROS, which were later rescued by the MSCs coculture to near normalcy. Taken together, all of these results primarily support MSCs-mediated modulation of stressed neuronal cell survival in vitro.

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Selective Release of Calpain Produced αII-Spectrin (α-Fodrin) Breakdown Products by Acute Neuronal Cell Death

Biological Chemistry ◽

10.1515/bc.2002.082 ◽

2002 ◽

Vol 383 (5) ◽

pp. 785-791 ◽

Cited By ~ 38

Author(s):

Satavisha Dutta ◽

Yuk Chun Chiu ◽

Albert W. Probert ◽

Kevin K.W. Wang

Keyword(s):

Cell Death ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Neuronal Injury ◽

Nmda Receptor Antagonist ◽

Breakdown Product ◽

Calpain Inhibitor ◽

Neural Cells

Abstract Activation of calpain results in the breakdown of α II spectrin (αfodrin), a neuronal cytoskeleton protein, which has previously been detected in various in vitro and in vivo neuronal injury models. In this study, a 150 kDa spectrin breakdown product (SBDP150) was found to be released into the cellconditioned media from SHSY5Y cells treated with the calcium channel opener maitotoxin (MTX). SBDP150 release can be readily quantified on immunoblot using an SBDP150- specific polyclonal antibody. Increase of SBDP150 also correlated with cell death in a timedependent manner. MDL28170, a selective calpain inhibitor, was the only protease inhibitor tested that significantly reduced MTXinduced SBDP150 release. The cellconditioned media of cerebellar granule neurons challenged with excitotoxins (NMDA and kainate) also exhibited a significant increase of SBDP150 that was attenuated by pretreatment with an NMDA receptor antagonist, R()-3-(2-carbopiperazine-4-yl)propyl-1- phosphonic acid (CPP), and MDL28170. In addition, hypoxic/hypoglycemic challenge of cerebrocortical cultures also resulted in SBDP150 liberation into the media. These results support the theory that an antibody based detection of SBDP150 in the cellconditioned media can be utilized to quantify injury to neural cells. Furthermore, SBDP150 may potentially be used as a surrogate biomarker for acute neuronal injury in clinical settings.

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The endogenous estrogen metabolite 2-methoxyestradiol induces apoptotic neuronal cell death in vitro

Life Sciences ◽

10.1016/0024-3205(96)00116-6 ◽

1996 ◽

Vol 58 (17) ◽

pp. 1461-1467 ◽

Cited By ~ 18

Author(s):

Yuzo Nakagawa-Yagi ◽

Nobuo Ogane ◽

Yutaka Inoki ◽

Naomi Kitoh

Keyword(s):

Cell Death ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Estrogen Metabolite ◽

Endogenous Estrogen

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A novel compound, RS-1178, specifically inhibits neuronal cell death mediated by β-amyloid-induced macrophage activation in vitro

Brain Research ◽

10.1016/s0006-8993(02)02898-6 ◽

2002 ◽

Vol 946 (2) ◽

pp. 298-306 ◽

Cited By ~ 16

Author(s):

Shigeko Uryu ◽

Shinya Tokuhiro ◽

Takako Murasugi ◽

Tomiichiro Oda

Keyword(s):

Cell Death ◽

Macrophage Activation ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Β Amyloid

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Cylindromatosis mediates neuronal cell death in vitro and in vivo

Cell Death and Differentiation ◽

10.1038/s41418-017-0046-7 ◽

2018 ◽

Vol 25 (8) ◽

pp. 1394-1407 ◽

Cited By ~ 6

Author(s):

Goutham K. Ganjam ◽

Nicole Angela Terpolilli ◽

Sebastian Diemert ◽

Ina Eisenbach ◽

Lena Hoffmann ◽

...

Keyword(s):

Cell Death ◽

Neuronal Cell Death ◽

Neuronal Cell

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Down-Regulation of miR-23a-3p Mediates Irradiation-Induced Neuronal Apoptosis

International Journal of Molecular Sciences ◽

10.3390/ijms21103695 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3695 ◽

Cited By ~ 2

Author(s):

Boris Sabirzhanov ◽

Oleg Makarevich ◽

James Barrett ◽

Isabel L. Jackson ◽

Alan I. Faden ◽

...

Keyword(s):

Dna Damage ◽

Cell Death ◽

Cytochrome C ◽

Neuronal Apoptosis ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Negative Regulator ◽

Down Regulation ◽

Bcl2 Family ◽

Mitochondrial Outer Membrane Permeabilization

Radiation-induced central nervous system toxicity is a significant risk factor for patients receiving cancer radiotherapy. Surprisingly, the mechanisms responsible for the DNA damage-triggered neuronal cell death following irradiation have yet to be deciphered. Using primary cortical neuronal cultures in vitro, we demonstrated that X-ray exposure induces the mitochondrial pathway of intrinsic apoptosis and that miR-23a-3p plays a significant role in the regulation of this process. Primary cortical neurons exposed to irradiation show the activation of DNA-damage response pathways, including the sequential phosphorylation of ATM kinase, histone H2AX, and p53. This is followed by the p53-dependent up-regulation of the pro-apoptotic Bcl2 family molecules, including the BH3-only molecules PUMA, Noxa, and Bim, leading to mitochondrial outer membrane permeabilization (MOMP) and the release of cytochrome c, which activates caspase-dependent apoptosis. miR-23a-3p, a negative regulator of specific pro-apoptotic Bcl-2 family molecules, is rapidly decreased after neuronal irradiation. By increasing the degradation of PUMA and Noxa mRNAs in the RNA-induced silencing complex (RISC), the administration of the miR-23a-3p mimic inhibits the irradiation-induced up-regulation of Noxa and Puma. These changes result in an attenuation of apoptotic processes such as MOMP, the release of cytochrome c and caspases activation, and a reduction in neuronal cell death. The neuroprotective effects of miR-23a-3p administration may not only involve the direct inhibition of pro-apoptotic Bcl-2 molecules downstream of p53 but also include the attenuation of secondary DNA damage upstream of p53. Importantly, we demonstrated that brain irradiation in vivo results in the down-regulation of miR-23a-3p and the elevation of pro-apoptotic Bcl2-family molecules PUMA, Noxa, and Bax, not only broadly in the cortex and hippocampus, except for Bax, which was up-regulated only in the hippocampus but also selectively in isolated neuronal populations from the irradiated brain. Overall, our data suggest that miR-23a-3p down-regulation contributes to irradiation-induced intrinsic pathways of neuronal apoptosis. These regulated pathways of neurodegeneration may be the target of effective neuroprotective strategies using miR-23a-3p mimics to block their development and increase neuronal survival after irradiation.

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Neuronal cell life, death, and axonal degeneration as regulated by the BCL-2 family proteins

Cell Death and Differentiation ◽

10.1038/s41418-020-00654-2 ◽

2020 ◽

Vol 28 (1) ◽

pp. 108-122

Author(s):

James M. Pemberton ◽

Justin P. Pogmore ◽

David W. Andrews

Keyword(s):

Cell Death ◽

Neuronal Apoptosis ◽

Axonal Degeneration ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Axon Degeneration ◽

Mitochondrial Outer Membrane ◽

Future Research ◽

System Disease ◽

Family Protein

AbstractAxonal degeneration and neuronal cell death are fundamental processes in development and contribute to the pathology of neurological disease in adults. Both processes are regulated by BCL-2 family proteins which orchestrate the permeabilization of the mitochondrial outer membrane (MOM). MOM permeabilization (MOMP) results in the activation of pro-apoptotic molecules that commit neurons to either die or degenerate. With the success of small-molecule inhibitors targeting anti-apoptotic BCL-2 proteins for the treatment of lymphoma, we can now envision the use of inhibitors of apoptosis with exquisite selectivity for BCL-2 family protein regulation of neuronal apoptosis in the treatment of nervous system disease. Critical to this development is deciphering which subset of proteins is required for neuronal apoptosis and axon degeneration, and how these two different outcomes are separately regulated. Moreover, noncanonical BCL-2 family protein functions unrelated to the regulation of MOMP, including impacting necroptosis and other modes of cell death may reveal additional potential targets and/or confounders. This review highlights our current understanding of BCL-2 family mediated neuronal cell death and axon degeneration, while identifying future research questions to be resolved to enable regulating neuronal survival pharmacologically.

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Degradation of mutant huntingtin via the ubiquitin/proteasome system is modulated by FE65

Biochemical Journal ◽

10.1042/bj20112175 ◽

2012 ◽

Vol 443 (3) ◽

pp. 681-689 ◽

Cited By ~ 15

Author(s):

Wan Ning Vanessa Chow ◽

Hon Wing Luk ◽

Ho Yin Edwin Chan ◽

Kwok-Fai Lau

Keyword(s):

Cell Death ◽

Degradation Mechanism ◽

Neuronal Cell Death ◽

Neuronal Cell ◽

Adaptor Protein ◽

Ubiquitin Proteasome System ◽

Exon 1 ◽

Ubiquitin Proteasome

An unstable expansion of the polyglutamine repeat within exon 1 of the protein Htt (huntingtin) causes HD (Huntington's disease). Mounting evidence shows that accumulation of N-terminal mutant Htt fragments is the source of disruption of normal cellular processes which ultimately leads to neuronal cell death. Understanding the degradation mechanism of mutant Htt and improving its clearance has emerged as a new direction in developing therapeutic approaches to treat HD. In the present study we show that the brain-enriched adaptor protein FE65 is a novel interacting partner of Htt. The binding is mediated through WW–polyproline interaction and is dependent on the length of the polyglutamine tract. Interestingly, a reduction in mutant Htt protein level was observed in FE65-knockdown cells, and the process requires the UPS (ubiquitin/proteasome system). Moreover, the ubiquitination level of mutant Htt was found to be enhanced when FE65 is knocked down. Immunofluroescence staining revealed that FE65 associates with mutant Htt aggregates. Additionally, we demonstrated that overexpression of FE65 increases mutant Htt-induced cell death both in vitro and in vivo. These results suggest that FE65 facilitates the accumulation of mutant Htt in cells by preventing its degradation via the UPS, and thereby enhances the toxicity of mutant Htt.

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