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Resilience of network activity in preconditioned neurons exposed to 'stroke-in-a-dish' insults. Neurochem Int 2021; 146:105035. [PMID: 33798645 DOI: 10.1016/j.neuint.2021.105035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 03/20/2021] [Accepted: 03/22/2021] [Indexed: 11/22/2022]
Abstract
Exposing cultured cortical neurons to stimulatory agents - the K+ channel blocker 4-aminopyridine (4-ap), and the GABAA receptor antagonist bicuculline (bic) - for 48 h induces down-regulated synaptic scaling, and preconditions neurons to withstand subsequent otherwise lethal 'stroke-in-a-dish' insults; however, the degree to which usual neuronal function remains is unknown. As a result, multi-electrode array and patch-clamp electrophysiological techniques were employed to characterize hallmarks of spontaneous synaptic activity over a 12-day preconditioning/insult experiment. Spiking frequency increased 8-fold immediately upon 4-ap/bic treatment but declined within the 48 h treatment window to sub-baseline levels that persisted long after washout. Preconditioning resulted in key markers of network activity - spiking frequency, bursting and avalanches - being impervious to an insult. Surprisingly, preconditioning resulted in higher peak NMDA mEPSC amplitudes, resulting in a decrease in the ratio of AMPA:NMDA mEPSC currents, suggesting a relative increase in synaptic NMDA receptors. An investigation of a broad mRNA panel of excitatory and inhibitory signaling mediators indicated preconditioning rapidly up-regulated GABA synthesis (GAD67) and BDNF, followed by up-regulation of neuronal activity-regulated pentraxin and down-regulation of presynaptic glutamate release (VGLUT1). Preconditioning also enhanced surface expression of GLT-1, which persisted following an insult. Overall, preconditioning resulted in a reduced spiking frequency which was impervious to subsequent exposure to 'stroke-in-a-dish' insults, a phenotype initiated predominantly by up-regulation of inhibitory neurotransmission, a lower neuronal postsynaptic AMPA: NMDA receptor ratio, and trafficking of GLT-1 to astrocyte plasma membranes.
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Meng SX, Wang B, Li WT. Intermittent hypoxia improves cognition and reduces anxiety-related behavior in APP/PS1 mice. Brain Behav 2020; 10:e01513. [PMID: 31877583 PMCID: PMC7010588 DOI: 10.1002/brb3.1513] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/20/2019] [Accepted: 11/08/2019] [Indexed: 01/09/2023] Open
Abstract
INTRODUCTION Although hypoxia can exacerbate symptoms of various neurological disorders, accumulating evidence has indicated that intermittent hypoxia (IH) may exert protective effects against brain diseases. In the present study, we aimed to determine whether exposure to IH exerts beneficial effects in a transgenic murine model of Alzheimer's disease (AD). Because comorbid anxiety is prevalent among patients with AD, we explored the effects of IH on anxiety-like behaviors and associated factors in APP/PS1 mice. METHODS APP/PS1 mice were subjected to IH for two weeks. We assessed cognitive performance and anxiety-related behavior using standard behavioral assessments. Amyloid beta (Aβ) levels in the hippocampus were assessed using immunofluorescence and enzyme-linked immunosorbent assays (ELISA). We also assessed cell morphology and brain-derived neurotrophic factor (BDNF) expression in the hippocampus. RESULTS Exposure to IH significantly increased cognitive performance and decreased anxiety-related behaviors in APP/PS1 mice. Immunofluorescence and ELISA results revealed that IH pretreatment significantly lowered Aβ levels in the cortex and hippocampus. Morphological studies validated the neuroprotective effect of IH exposure on hippocampal neurogenesis. Molecular studies revealed IH-enhanced BDNF expression and inhibition of apoptosis-related protein expression in the hippocampus of APP/PS1 mice. CONCLUSIONS Our study demonstrates that IH improves cognition and reduces anxiety in a murine model of AD. Thus, further studies are required to determine whether IH can be used as a preventive/adjuvant therapy in patients with AD.
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Affiliation(s)
- Sheng-Xi Meng
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Bing Wang
- Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China
| | - Wen-Tao Li
- Department of Vasculocardiology, Municipal Hospital of Traditional Chinese Medicine Affiliated to Shanghai University of Traditional Chinese Medicine, Shanghai, China
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Kudryashova IV. The Molecular Basis of Destabilization of Synapses as a Factor of Structural Plasticity. NEUROCHEM J+ 2019. [DOI: 10.1134/s1819712419010136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Cerebral Ischemic Postconditioning Plays a Neuroprotective Role through Regulation of Central and Peripheral Glutamate. BIOMED RESEARCH INTERNATIONAL 2018; 2018:6316059. [PMID: 30112410 PMCID: PMC6077516 DOI: 10.1155/2018/6316059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Accepted: 07/12/2018] [Indexed: 01/30/2023]
Abstract
Following cerebral ischemia/reperfusion (I/R) injury, a series of pathophysiological processes are stimulated in both the central nervous system (CNS) and the periphery, including, but not limited to, the peripheral immune and endocrine systems and underregulation of the neuroendocrine-immune network. Glutamate (Glu) is an important excitatory neurotransmitter in the CNS; its excitotoxicity following cerebral ischemia has been a focus of study for several decades. In addition, as a novel immunoregulator, Glu also regulates immune activity in both the CNS and periphery and may connect the CNS and periphery through regulation of the neuroendocrine-immune network. Ischemic postconditioning (IPostC) is powerful and activates various endogenous neuroprotective mechanisms following cerebral I/R, but only a few studies have focused on the mechanisms associated with Glu to date. Given that Glu plays an important and complex pathophysiological role, the understanding of Glu-related mechanisms of IPostC is an interesting area of research, which we review here.
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Downregulation of glutamic acid decarboxylase in Drosophila TDP-43-null brains provokes paralysis by affecting the organization of the neuromuscular synapses. Sci Rep 2018; 8:1809. [PMID: 29379112 PMCID: PMC5789004 DOI: 10.1038/s41598-018-19802-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 01/05/2018] [Indexed: 11/12/2022] Open
Abstract
Amyotrophic lateral sclerosis is a progressive neurodegenerative disease that affects the motor system, comprised of motoneurons and associated glia. Accordingly, neuronal or glial defects in TDP-43 function provoke paralysis due to the degeneration of the neuromuscular synapses in Drosophila. To identify the responsible molecules and mechanisms, we performed a genome wide proteomic analysis to determine differences in protein expression between wild-type and TDP-43-minus fly heads. The data established that mutant insects presented reduced levels of the enzyme glutamic acid decarboxylase (Gad1) and increased concentrations of extracellular glutamate. Genetic rescue of Gad1 activity in neurons or glia was sufficient to recuperate flies locomotion, synaptic organization and glutamate levels. Analogous recovery was obtained by treating TDP-43-null flies with glutamate receptor antagonists demonstrating that Gad1 promotes synapses formation and prevents excitotoxicity. Similar suppression of TDP-43 provoked the downregulation of GAD67, the Gad1 homolog protein in human neuroblastoma cell lines and analogous modifications were observed in iPSC-derived motoneurons from patients carrying mutations in TDP-43, uncovering conserved pathological mechanisms behind the disease.
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Curcio M, Salazar IL, Mele M, Canzoniero LMT, Duarte CB. Calpains and neuronal damage in the ischemic brain: The swiss knife in synaptic injury. Prog Neurobiol 2016; 143:1-35. [PMID: 27283248 DOI: 10.1016/j.pneurobio.2016.06.001] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 03/22/2016] [Accepted: 05/09/2016] [Indexed: 12/26/2022]
Abstract
The excessive extracellular accumulation of glutamate in the ischemic brain leads to an overactivation of glutamate receptors with consequent excitotoxic neuronal death. Neuronal demise is largely due to a sustained activation of NMDA receptors for glutamate, with a consequent increase in the intracellular Ca(2+) concentration and activation of calcium- dependent mechanisms. Calpains are a group of Ca(2+)-dependent proteases that truncate specific proteins, and some of the cleavage products remain in the cell, although with a distinct function. Numerous studies have shown pre- and post-synaptic effects of calpains on glutamatergic and GABAergic synapses, targeting membrane- associated proteins as well as intracellular proteins. The resulting changes in the presynaptic proteome alter neurotransmitter release, while the cleavage of postsynaptic proteins affects directly or indirectly the activity of neurotransmitter receptors and downstream mechanisms. These alterations also disturb the balance between excitatory and inhibitory neurotransmission in the brain, with an impact in neuronal demise. In this review we discuss the evidence pointing to a role for calpains in the dysregulation of excitatory and inhibitory synapses in brain ischemia, at the pre- and post-synaptic levels, as well as the functional consequences. Although targeting calpain-dependent mechanisms may constitute a good therapeutic approach for stroke, specific strategies should be developed to avoid non-specific effects given the important regulatory role played by these proteases under normal physiological conditions.
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Affiliation(s)
- Michele Curcio
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Ivan L Salazar
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; Doctoral Programme in Experimental Biology and Biomedicine, Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; Institute for Interdisciplinary Research, University of Coimbra (IIIUC), 3030-789 Coimbra, Portugal
| | - Miranda Mele
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | | | - Carlos B Duarte
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal; Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal.
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The Toxic Effect of ALLN on Primary Rat Retinal Neurons. Neurotox Res 2016; 30:392-406. [DOI: 10.1007/s12640-016-9624-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Revised: 04/04/2016] [Accepted: 04/16/2016] [Indexed: 10/21/2022]
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Kudryashova IV, Onufriev MV, Gulyaeva NV. Caspase-3 and calpain: Differently directed involvement in presynaptic long-term plasticity. NEUROCHEM J+ 2014. [DOI: 10.1134/s181971241403009x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Glutamate and GABA-Metabolizing Enzymes in Post-mortem Cerebellum in Alzheimer’s Disease: Phosphate-Activated Glutaminase and Glutamic Acid Decarboxylase. THE CEREBELLUM 2014; 13:607-15. [DOI: 10.1007/s12311-014-0573-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Dieb W, Hafidi A. Mechanism of GABA involvement in post-traumatic trigeminal neuropathic pain: activation of neuronal circuitry composed of PKCγ interneurons and pERK1/2 expressing neurons. Eur J Pain 2014; 19:85-96. [PMID: 24890317 DOI: 10.1002/ejp.525] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/04/2014] [Indexed: 01/27/2023]
Abstract
BACKGROUND GABA disinhibition within the spinal dorsal horn has been implicated in pain hypersensitivity on injury in different neuropathic models. However, GABA alteration has been explored in only one study on trigeminal neuropathic pain. METHODS The present study investigated the implication of GABA in trigeminal dynamic mechanical allodynia (DMA) obtained after chronic constriction of the infraorbital nerve (CCI-IoN), and explored the cellular and molecular mechanisms by which GABA dysfunction induced DMA. RESULTS Our data demonstrated a significant decrease in labelling in two GABA cell markers, glutamate acid decarboxylase (GAD67), and parvalbumin, in the medullary dorsal horn (MDH) of allodynic rats in comparison to sham rats. Increasing GABA by intracisternal injections of vigabatrin (VGB), a blocker of the catabolic enzyme GABA transaminase, alleviated pain behaviour and restored normal GABA cell marker expression in allodynic MDH. Interestingly, intracisternal VGB administration also significantly decreased PKCγ staining, i.e., of its phosphorylated active form and the number of pERK1/2 positive cells within the MDH. These two markers were highly expressed in allodynic MDH. CONCLUSION The circuitry composed of PKCγ and pERK1/2 cells is silent under physiological conditions but is activated after CCI-IoN, therefore, switching touch stimuli to pain sensation. The decrease of GABA transmission constituted a key factor in the activation of this neuronal circuitry, which opens the gate for non-noxious stimuli to reach nociceptive projection neurons in lamina I.
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Affiliation(s)
- W Dieb
- Neuropsycho-pharmacologie des systèmes dopaminergiques sous corticaux, Université d'Auvergne, Clermont-Ferrand, France
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Xiong B, Shi QQ, Miao CH. Dexmedetomidine renders a brain protection on hippocampal formation through inhibition of nNOS-NO signalling in endotoxin-induced shock rats. Brain Inj 2014; 28:1003-8. [DOI: 10.3109/02699052.2014.888765] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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12
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Kudryashova IV. Molecular mechanisms of short-term plasticity as a basis of frequency coding: The role of proteolytic systems. NEUROCHEM J+ 2014. [DOI: 10.1134/s1819712414010097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Buddhala C, Suarez M, Modi J, Prentice H, Ma Z, Tao R, Wu JY. Calpain cleavage of brain glutamic acid decarboxylase 65 is pathological and impairs GABA neurotransmission. PLoS One 2012; 7:e33002. [PMID: 22427928 PMCID: PMC3299728 DOI: 10.1371/journal.pone.0033002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 02/02/2012] [Indexed: 11/19/2022] Open
Abstract
Previously, we have shown that the GABA synthesizing enzyme, L-glutamic acid decarboxylase 65 (GAD65) is cleaved to form its truncated form (tGAD65) which is 2-3 times more active than the full length form (fGAD65). The enzyme responsible for cleavage was later identified as calpain. Calpain is known to cleave its substrates either under a transient physiological stimulus or upon a sustained pathological insult. However, the precise role of calpain cleavage of fGAD65 is poorly understood. In this communication, we examined the cleavage of fGAD65 under diverse pathological conditions including rats under ischemia/reperfusion insult as well as rat brain synaptosomes and primary neuronal cultures subjected to excessive stimulation with high concentration of KCl. We have shown that the formation of tGAD65 progressively increases with increasing stimulus concentration both in rat brain synaptosomes and primary rat embryo cultures. More importantly, direct cleavage of synaptic vesicle - associated fGAD65 by calpain was demonstrated and the resulting tGAD65 bearing the active site of the enzyme was detached from the synaptic vesicles. Vesicular GABA transport of the newly synthesized GABA was found to be reduced in calpain treated SVs. Furthermore, we also observed that the levels of tGAD65 in the focal cerebral ischemic rat brain tissue increased corresponding to the elevation of local glutamate as indicated by microdialysis. Moreover, the levels of tGAD65 was also proportional to the degree of cell death when the primary neuronal cultures were exposed to high KCl. Based on these observations, we conclude that calpain-mediated cleavage of fGAD65 is pathological, presumably due to decrease in the activity of synaptic vesicle - associated fGAD65 resulting in a decrease in the GABA synthesis - packaging coupling process leading to reduced GABA neurotransmission.
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Affiliation(s)
- Chandana Buddhala
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
| | - Marjorie Suarez
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
| | - Jigar Modi
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
| | - Howard Prentice
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
| | - Zhiyuan Ma
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
| | - Rui Tao
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
| | - Jang Yen Wu
- Department of Biomedical Science, Charles E Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida, United States of America,
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Monnerie H, Hsu FC, Coulter DA, Le Roux PD. Role of the NR2A/2B subunits of the N-methyl-D-aspartate receptor in glutamate-induced glutamic acid decarboxylase alteration in cortical GABAergic neurons in vitro. Neuroscience 2010; 171:1075-90. [PMID: 20923697 DOI: 10.1016/j.neuroscience.2010.09.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Revised: 09/22/2010] [Accepted: 09/23/2010] [Indexed: 12/21/2022]
Abstract
The vulnerability of brain neuronal cell subpopulations to neurologic insults varies greatly. Among cells that survive a pathological insult, for example ischemia or brain trauma, some may undergo morphological and/or biochemical changes that may compromise brain function. The present study is a follow-up of our previous studies that investigated the effect of glutamate-induced excitotoxicity on the GABA synthesizing enzyme glutamic acid decarboxylase (GAD65/67)'s expression in surviving DIV 11 cortical GABAergic neurons in vitro [Monnerie and Le Roux, (2007) Exp Neurol 205:367-382, (2008) Exp Neurol 213:145-153]. An N-methyl-D-aspartate receptor (NMDAR)-mediated decrease in GAD expression was found following glutamate exposure. Here we examined which NMDAR subtype(s) mediated the glutamate-induced change in GAD protein levels. Western blotting techniques on cortical neuron cultures showed that glutamate's effect on GAD proteins was not altered by NR2B-containing diheteromeric (NR1/NR2B) receptor blockade. By contrast, blockade of triheteromeric (NR1/NR2A/NR2B) receptors fully protected against a decrease in GAD protein levels following glutamate exposure. When receptor location on the postsynaptic membrane was examined, extrasynaptic NMDAR stimulation was observed to be sufficient to decrease GAD protein levels similar to that observed after glutamate bath application. Blocking diheteromeric receptors prevented glutamate's effect on GAD proteins after extrasynaptic NMDAR stimulation. Finally, NR2B subunit examination with site-specific antibodies demonstrated a glutamate-induced, calpain-mediated alteration in NR2B expression. These results suggest that glutamate-induced excitotoxic NMDAR stimulation in cultured GABAergic cortical neurons depends upon subunit composition and receptor location (synaptic vs. extrasynaptic) on the neuronal membrane. Biochemical alterations in surviving cortical GABAergic neurons in various disease states may contribute to the altered balance between excitation and inhibition that is often observed after injury.
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Affiliation(s)
- H Monnerie
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA
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Baptista MS, Melo CV, Armelão M, Herrmann D, Pimentel DO, Leal G, Caldeira MV, Bahr BA, Bengtson M, Almeida RD, Duarte CB. Role of the proteasome in excitotoxicity-induced cleavage of glutamic acid decarboxylase in cultured hippocampal neurons. PLoS One 2010; 5:e10139. [PMID: 20405034 PMCID: PMC2853570 DOI: 10.1371/journal.pone.0010139] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2009] [Accepted: 03/16/2010] [Indexed: 12/22/2022] Open
Abstract
Glutamic acid decarboxylase is responsible for synthesizing GABA, the major inhibitory neurotransmitter, and exists in two isoforms—GAD65 and GAD67. The enzyme is cleaved under excitotoxic conditions, but the mechanisms involved and the functional consequences are not fully elucidated. We found that excitotoxic stimulation of cultured hippocampal neurons with glutamate leads to a time-dependent cleavage of GAD65 and GAD67 in the N-terminal region of the proteins, and decrease the corresponding mRNAs. The cleavage of GAD67 was sensitive to the proteasome inhibitors MG132, YU102 and lactacystin, and was also abrogated by the E1 ubiquitin ligase inhibitor UBEI-41. In contrast, MG132 and UBEI-41 were the only inhibitors tested that showed an effect on GAD65 cleavage. Excitotoxic stimulation with glutamate also increased the amount of GAD captured in experiments where ubiquitinated proteins and their binding partners were isolated. However, no evidences were found for direct GADs ubiquitination in cultured hippocampal neurons, and recombinant GAD65 was not cleaved by purified 20S or 26S proteasome preparations. Since calpains, a group of calcium activated proteases, play a key role in GAD65/67 cleavage under excitotoxic conditions the results suggest that GADs are cleaved after ubiquitination and degradation of an unknown binding partner by the proteasome. The characteristic punctate distribution of GAD65 along neurites of differentiated cultured hippocampal neurons was significantly reduced after excitotoxic injury, and the total GAD activity measured in extracts from the cerebellum or cerebral cortex at 24h postmortem (when there is a partial cleavage of GADs) was also decreased. The results show a role of the UPS in the cleavage of GAD65/67 and point out the deregulation of GADs under excitotoxic conditions, which is likely to affect GABAergic neurotransmission. This is the first time that the UPS has been implicated in the events triggered during excitotoxicity and the first molecular target of the UPS affected in this cell death process.
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Affiliation(s)
- Márcio S. Baptista
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Carlos V. Melo
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
- * E-mail:
| | - Mário Armelão
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Dennis Herrmann
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Diogo O. Pimentel
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Graciano Leal
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Margarida V. Caldeira
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Ben A. Bahr
- Biotechnology Research and Training Center, University of North Carolina, Pembroke, North Carolina, United States of America
| | - Mário Bengtson
- Department of Cancer and Cell Biology, Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Ramiro D. Almeida
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Carlos B. Duarte
- Center for Neuroscience and Cell Biology, Department of Life Sciences, University of Coimbra, Coimbra, Portugal
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Yamashima T, Oikawa S. The role of lysosomal rupture in neuronal death. Prog Neurobiol 2009; 89:343-58. [PMID: 19772886 DOI: 10.1016/j.pneurobio.2009.09.003] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 09/11/2009] [Accepted: 09/15/2009] [Indexed: 12/19/2022]
Abstract
Apoptosis research in the past two decades has provided an enormous insight into its role in regulating cell death. However, apoptosis is only part of the story, and inhibition of neuronal necrosis may have greater impact than apoptosis, on the treatment of stroke, traumatic brain injury, and neurodegenerative diseases. Since the "calpain-cathepsin hypothesis" was first formulated, the calpain- and cathepsin-mediated regulation of necrotic cascades observed in monkeys, has been demonstrated to be a common neuronal death mechanism occurring from simpler organisms to humans. However, the detailed mechanism inducing lysosomal destabilization still remains poorly understood. Heat-shock protein-70 (Hsp70) is known to stabilize lysosomal membrane and protect cells from oxidative stress and apoptotic stimuli in many cell death pathways. Recent proteomics approach comparing pre- and post-ischemic hippocampal CA1 neurons as well as normal and glaucoma-suffered retina of primates, suggested that the substrate protein upon which activated calpain acts at the lysosomal membrane of neurons might be Hsp70. Understanding the interaction between activated calpains and Hsp70 will help to unravel the mechanism that destabilizes the lysosomal membrane, and will provide new insights into clarifying the whole cascade of neuronal necrosis. Although available evidence is circumferential, it is hypothesized that activated calpain cleaves oxidative stress-induced carbonylated Hsp70.1 (a major human Hsp70) at the lysosomal membrane, which result in lysosomal rupture/permeabilization. This review aims at highlighting the possible mechanism of lysosomal rupture in neuronal death by a modified "calpain-cathepsin hypothesis". As the autophagy-lysosomal degradation pathway is a target of oxidative stress, the implication of autophagy is also discussed.
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Affiliation(s)
- Tetsumori Yamashima
- Department of Restorative Neurosurgery, Kanazawa University Graduate School of Medical Science, Kanazawa 920-8641, Japan.
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Excitotoxic neonatal damage induced by monosodium glutamate reduces several GABAergic markers in the cerebral cortex and hippocampus in adulthood. Int J Dev Neurosci 2009; 27:845-55. [DOI: 10.1016/j.ijdevneu.2009.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 07/07/2009] [Accepted: 07/29/2009] [Indexed: 11/23/2022] Open
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