Autophagy fails to prevent glucose deprivation/glucose reintroduction-induced neuronal death due to calpain-mediated lysosomal dysfunction in cortical neurons

The cellular mechanisms that lead to neuronal death following glucose deprivation are not known, although it is recognized that hypoglycemia can lead to perturbations in intracellular calcium ([Ca2+]i) levels. Recently, activation of A1 adenosine receptors (A1AR) has been shown to alter [Ca2+]i and promote neuronal death. Thus, we examined if A1AR activation contributes to hypoglycemia-induced neuronal injury using rat cortical neurons. First, we observed that hypoglycemia was associated with large increases in neuronal adenosine release. Next, decreased neuronal viability was seen with progressive reduction in glucose concentration (25, 6, 3, 0.75 and 0 mM). Using the calcium-sensitive dye, Fluo-3, we observed both acute and long-term changes in relative [Ca2+]i during hypoglycemic conditions. Demonstrating a role for adenosine in this process, both the loss in neuronal viability and the early changes in [Ca2+]i were reversed by treatment with A1AR antagonists (8-cyclopentyl, 1,3-dipropylxanthine; 9-chloro-2-(2-furyl)(1,2,4)-triazolo(1,5-c)quinazolin-5-amine; and N-cyclopentyl-9-methyladenine). We also found that hypoglycemia induced the expression of the pro-apoptotic enzyme, caspase-3, and that A1AR antagonism reversed hypoglycemia-induced caspase-3 activity. Collectively, these data show that hypoglycemia induces A1ARs activation leading to alterations in [Ca2+]i, which plays a prominent role in leading to hypoglycemia-induced neuronal death.

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A Concerted Role of Na+—K+—Cl− Cotransporter and Na+/Ca2+ Exchanger in Ischemic Damage

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/sj.jcbfm.9600561 ◽

2007 ◽

Vol 28 (4) ◽

pp. 737-746 ◽

Cited By ~ 24

Author(s):

Jing Luo ◽

Yanping Wang ◽

Hai Chen ◽

Douglas B Kintner ◽

Sam W Cramer ◽

...

Keyword(s):

Cell Death ◽

Cerebral Ischemia ◽

Mortality Rate ◽

Neuronal Death ◽

Cortical Neurons ◽

Infarct Volume ◽

Glucose Deprivation ◽

Ischemic Damage ◽

Oxygen And Glucose Deprivation

Na+–K+–Cl− cotransporter isoform 1 (NKCC1) and Na+/Ca2+ exchanger isoform 1 (NCX1) were expressed in cortical neurons. Three hours of oxygen and glucose deprivation (OGD) significantly increased expression of full-length NCX1 protein (∼116 kDa), which remained elevated during 1 to 21 h reoxygenation (REOX) and was accompanied with concurrent cleavage of NCX1. Na+/Ca2+ exchanger isoform 1 heterozygous (NCX1+/−) neurons with ∼50% less of NCX1 protein exhibited ∼64% reduction in NCX-mediated Ca2+ influx. Expression of NCX1 and NKCC1 proteins was reduced in double heterozygous (NCX1+/−/NKCC1+/−) neurons. NCX-mediated Ca2+ influx was nearly abolished in these neurons. Three-hour OGD and 21-h REOX caused ∼80% mortality rate in NCX1+/+ neurons and in NCX1+/− neurons. In contrast, NKCC1+/− neurons exhibited ∼45% less cell death. The lowest mortality rate was found in NCX1+/−/NKCC1+/− neurons (∼65% less neuronal death). The increased tolerance to ischemic damage was also observed in NCX1+/−/NKCC1+/− brains after transient cerebral ischemia. NCX1+/−/NKCC1+/− mice had a significantly reduced infarct volume at 24 and 72 h reperfusion. In conclusion, these data suggest that NKCC1 in conjunction with NCX1 plays a role in reperfusion-induced brain injury after ischemia.

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Tissue-Type Plasminogen Activator is Involved in the Process of Neuronal Death Induced by Oxygen–Glucose Deprivation in Culture

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200106000-00001 ◽

2001 ◽

Vol 21 (6) ◽

pp. 631-634 ◽

Cited By ~ 44

Author(s):

Nobuo Nagai ◽

Seiji Yamamoto ◽

Takashi Tsuboi ◽

Hayato Ihara ◽

Tetsumei Urano ◽

...

Keyword(s):

Plasminogen Activator ◽

Neuronal Death ◽

Cortical Neurons ◽

Gene Knockout ◽

Glucose Deprivation ◽

Tissue Type ◽

Oxygen Glucose Deprivation ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator ◽

Cultured Cortical Neurons

Effect of tissue-type plasminogen activator (tPA) on oxygen–glucose deprivation (OGD) was studied in cultured cortical neurons prepared from tPA gene knockout (tPA-KO) and wild-type (Wt) mice. Three hours of OGD induced 45% and 23% of neuronal death in Wt and tPA-KO mice, respectively. Neuronal death in tPA-KO mice was increased to 42% by additional tPA. Six hours of OGD induced 80% and 40% of neuronal death in Wt and tPA-KO mice, respectively, whereas the addition of tPA increased to 62% in tPA-KO mice. These results suggest that tPA is directly involved in the process of neuronal death induced by ischemia-mimic stress without involving vascular or circulatory components.

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Glutamate preconditioning prevents neuronal death induced by combined oxygen–glucose deprivation in cultured cortical neurons

European Journal of Pharmacology ◽

10.1016/j.ejphar.2008.05.047 ◽

2008 ◽

Vol 589 (1-3) ◽

pp. 85-93 ◽

Cited By ~ 44

Author(s):

Chia-Ho Lin ◽

Po-See Chen ◽

Po-Wu Gean

Keyword(s):

Neuronal Death ◽

Cortical Neurons ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Cultured Cortical Neurons

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IRE1α RIDD activity induced under ER stress drives neuronal death by the degradation of 14-3-3 θ mRNA in cortical neurons during glucose deprivation

Cell Death Discovery ◽

10.1038/s41420-021-00518-9 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Juan Carlos Gómora-García ◽

Cristian Gerónimo-Olvera ◽

Xochitl Pérez-Martínez ◽

Lourdes Massieu

Keyword(s):

Cell Death ◽

Protein Synthesis ◽

Brain Injury ◽

Neuronal Death ◽

Cortical Neurons ◽

Nuclear Translocation ◽

Adaptor Protein ◽

Severe Hypoglycemia ◽

Glucose Deprivation ◽

Negative Regulator

AbstractAltered protein homeostasis is associated with neurodegenerative diseases and acute brain injury induced under energy depletion conditions such as ischemia. The accumulation of damaged or unfolded proteins triggers the unfolded protein response (UPR), which can act as a homeostatic response or lead to cell death. However, the factors involved in turning and adaptive response into a cell death mechanism are still not well understood. Several mechanisms leading to brain injury induced by severe hypoglycemia have been described but the contribution of the UPR has been poorly studied. Cell responses triggered during both the hypoglycemia and the glucose reinfusion periods can contribute to neuronal death. Therefore, we have investigated the activation dynamics of the PERK and the IRE1α branches of the UPR and their contribution to neuronal death in a model of glucose deprivation (GD) and glucose reintroduction (GR) in cortical neurons. Results show a rapid activation of the PERK/p-eIF2α/ATF4 pathway leading to protein synthesis inhibition during GD, which contributes to neuronal adaptation, however, sustained blockade of protein synthesis during GR promotes neuronal death. On the other hand, IRE1α activation occurs early during GD due to its interaction with BAK/BAX, while ASK1 is recruited to IRE1α activation complex during GR promoting the nuclear translocation of JNK and the upregulation of Chop. Most importantly, results show that IRE1α RNase activity towards its splicing target Xbp1 mRNA occurs late after GR, precluding a homeostatic role. Instead, IRE1α activity during GR drives neuronal death by positively regulating ASK1/JNK activity through the degradation of 14-3-3 θ mRNA, a negative regulator of ASK and an adaptor protein highly expressed in brain, implicated in neuroprotection. Collectively, results describe a novel regulatory mechanism of cell death in neurons, triggered by the downregulation of 14-3-3 θ mRNA induced by the IRE1α branch of the UPR.

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Nrf2 mediates the neuroprotective effect of isoflurane preconditioning in cortical neuron injury induced by oxygen-glucose deprivation

Human & Experimental Toxicology ◽

10.1177/0960327121989416 ◽

2021 ◽

pp. 096032712198941

Author(s):

X-S Liu ◽

X-L Bai ◽

Z-X Wang ◽

S-Y Xu ◽

Y Ma ◽

...

Keyword(s):

Oxidative Stress ◽

Cortical Neuron ◽

Cortical Neurons ◽

Glucose Deprivation ◽

Oxygen Glucose Deprivation ◽

Lactate Dehydrogenase Activity ◽

Primary Mouse ◽

Ldh Release ◽

Neuron Injury ◽

And Oxidative Stress

Objective: To investigate how nuclear factor-E2-related factor 2 (Nrf2) involved in the protective effect of isoflurane (Iso) preconditioning in oxygen glucose deprivation (OGD)-induced cortical neuron injury. Methods: Primary mouse cortical neurons were divided into Control, ML385 (an Nrf2 inhibitor), Iso, Iso + ML385, OGD, ML385 + OGD, Iso + OGD, and Iso + ML385 + OGD groups. Lactate dehydrogenase activity (LDH) release and oxidative stress indexes were quantified. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to detect cell viability, Annexin V-FITC/propidium iodide (PI) staining to measure cell apoptosis, dichloro-dihydro-fluorescein diacetate (DCFH-DA) method to test reactive oxygen species (ROS), and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Western blotting to evaluate genes and protein expression. Results: Iso preconditioning reduced LDH release and inhibited cell cytotoxicity in OGD-induced cortical neurons, which was abolished by ML385. Iso preconditioning increased the Nrf2 nuclear translocation in cortical neurons. Meanwhile, Iso decreased the OGD-induced apoptosis with the down-regulations of Bax and Caspase-3 and the up-regulation of Bcl-2, which was reversed by ML385. OGD enhanced the level of ROS and malondialdehyde (MDA) in cortical neurons, but reduced the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), which were aggravated in ML385 + OGD group and mitigated in Iso + OGD group. No observable difference was found between OGD group and Iso + ML385 + OGD group regarding apoptosis-related proteins and oxidative stress-related indexes. Conclusion: Iso preconditioning up-regulated Nrf2 level to play its protective role in OGD-induced mouse cortical neuron injury.

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