Novel role of glial syntaxin-1B in supporting neuronal survival

2014 ◽  
Vol 130 (4) ◽  
pp. 469-471
Author(s):  
Seungmee Park ◽  
Na-Ryum Bin ◽  
Shuzo Sugita
Keyword(s):  
Neuronal Survival ◽  
Syntaxin 1B

Role of Nogo-A in neuronal survival in the reperfused ischaemic brain

2009 ◽  
Vol 36 (S 02) ◽  
Author(s):  
A El Ali ◽  
E Kilic ◽  
Ü Kilic ◽  
Z Guo ◽  
CL Bassetti ◽  
...  
Keyword(s):  
Neuronal Survival ◽  
Ischaemic Brain

scholarly journals Stoichiometric Analysis of Shifting in Subcellular Compartmentalization of HSP70 within Ischemic Penumbra

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3578
Author(s):  
Federica Mastroiacovo ◽  
Francesca Biagioni ◽  
Paola Lenzi ◽  
Larisa Ryskalin ◽  
Stefano Puglisi-Allegra ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Neuronal Survival ◽  
Hsp 70 ◽  
Preclinical Models ◽  
Brain Areas ◽  
Cell Compartments ◽  
Control Brain ◽  
Disease Modifier ◽  
Subcellular Compartmentalization

The heat shock protein (HSP) 70 is considered the main hallmark in preclinical studies to stain the peri-infarct region defined area penumbra in preclinical models of brain ischemia. This protein is also considered as a potential disease modifier, which may improve the outcome of ischemic damage. In fact, the molecule HSP70 acts as a chaperonine being able to impact at several level the homeostasis of neurons. Despite being used routinely to stain area penumbra in light microscopy, the subcellular placement of this protein within area penumbra neurons, to our knowledge, remains undefined. This is key mostly when considering studies aimed at deciphering the functional role of this protein as a determinant of neuronal survival. The general subcellular placement of HSP70 was grossly reported in studies using confocal microscopy, although no direct visualization of this molecule at electron microscopy was carried out. The present study aims to provide a direct evidence of HSP70 within various subcellular compartments. In detail, by using ultrastructural morphometry to quantify HSP70 stoichiometrically detected by immuno-gold within specific organelles we could compare the compartmentalization of the molecule within area penumbra compared with control brain areas. The study indicates that two cell compartments in control conditions own a high density of HSP70, cytosolic vacuoles and mitochondria. In these organelles, HSP70 is present in amount exceeding several-fold the presence in the cytosol. Remarkably, within area penumbra a loss of such a specific polarization is documented. This leads to the depletion of HSP70 from mitochondria and mostly cell vacuoles. Such an effect is expected to lead to significant variations in the ability of HSP70 to exert its physiological roles. The present findings, beyond defining the neuronal compartmentalization of HSP70 within area penumbra may lead to a better comprehension of its beneficial/detrimental role in promoting neuronal survival.

Neuroprotection by propofol in acute mechanical injury: role of GABAergic inhibition

1996 ◽  
Vol 76 (4) ◽  
pp. 2412-2422 ◽  
Author(s):  
G. S. Hollrigel ◽  
K. Toth ◽  
I. Soltesz
Keyword(s):  
Cell Death ◽  
Gabaa Receptor ◽  
Granule Cells ◽  
Neuronal Survival ◽  
Brain Slices ◽  
Mechanical Injury ◽  
Protective Effects ◽  
General Anesthetic ◽  
Gabaa Receptor Antagonist

1. Whole cell patch-clamp and extracellular field recordings were obtained from granule cells of the dentate gyrus in 400-microns-thick brain slices of the adult rat to determine the actions of the intravenous general anesthetic 2,6-diisopropylphenol (propofol) on acute neuronal survival and preservation of synaptic integrity after amputation of dendrites (dendrotomy), and to determine the role of gamma-aminobutyric acid-A (GABAA)-receptor-mediated inhibition in the neuroprotective effects of propofol. The actions of propofol were compared with those exerted by another widely used intravenous general anesthetic, 5-ethyl-5-[1-methylbutyl]-2-thiobarbituric acid (thiopental). 2. Propofol (10 microM) increased the frequency (control: 5.9 +/- 0.9 Hz, mean +/- SE; propofol: 10.5 +/- 1.3 Hz) and the single-exponential decay time constant (tau D) (control: 4.5 +/- 0.2 ms; propofol: 15.3 +/- 1.5 ms) of miniature inhibitory postsynaptic currents (mIPSCs) recorded in control neurons. Thiopental (25 microM) also increased the tau D (14.3 +/- 0.9 ms) of mISPCs, but had no effect on mIPSC frequency. Both anesthetics potentiated mIPSCs at low concentrations (propofol: 5 microM; thiopental: 1 microM). Propofol and thiopental did not change the peak amplitude and rise times of mIPSCs. 3. Propofol (10 microM) was able to depress the excitability of control granule cells, as determined by the reduction in the amplitude of the orthodromic population spikes. This depression could be prevented by the GABAA receptor antagonist bicuculline (50 microM), indicating that propofol reduces excitability via GABAA receptor functions. 4. Propofol and thiopental were neuroprotectant (assessed by antidromic population responses 2-5 h after injury) if present before and during the amputation of the granule cell dendrites. The protective actions were dose dependent, and at high doses (propofol: 200 microM; thiopental: 400 microM) the anesthetics were as neuroprotective against dendrotomy-induced cell death as 2-amino 5-phosphovaleric acid (APV) and 6-cyano-7-nitroquinoxaline-2,3 dione (CNQX). The protective effects of the anesthetics were completely blocked with the GABAA receptor antagonists picrotoxin or bicuculline, and were mimicked by the GABAA receptor agonist muscimol (100 microM). 5. Propofol, in contrast to APV and CNQX, could not prevent the dendrotomy-induced Ca(2+)-dependent and long-lasting changes in mIPSC decay kinetics (appearance of a double-exponential, prolonged decay). 6. The protective effects of the anesthetics and those of APV and CNQX on neuronal survival were not significant when the drugs were applied after dendrotomy, indicating that dendrotomy carried out 150-200 microns from the soma without neuroprotective agents rapidly induces irreversible acute degeneration in most injured neurons. The failure to rescue cells from dendrotomy-induced injury did not result from a decreased sensitivity of the GABAA receptors to the anesthetics, because the potentiating effects of the anesthetics on mIPSCs from control and dendrotomized neurons were not different. 7. These data indicate that propofol potentiates synaptic inhibition pre- and postsynaptically, and, when present during dendrotomy, it can protect neurons from acute mechanical-injury induced cell death via potentiation of GABAA receptor functions. However, propofol fails to provide neuroprotection against dendrotomy-induced changes in synaptic physiology.

scholarly journals HPC-1/syntaxin 1A and syntaxin 1B play distinct roles in neuronal survival

2014 ◽  
Vol 130 (4) ◽  
pp. 514-525 ◽  
Author(s):  
Takefumi Kofuji ◽  
Tomonori Fujiwara ◽  
Masumi Sanada ◽  
Tatsuya Mishima ◽  
Kimio Akagawa
Keyword(s):  
Neuronal Survival ◽  
Syntaxin 1A ◽  
Syntaxin 1B

Senescence marker protein 30 confers neuroprotection in oxygen-glucose deprivation/reoxygenation-injured neurons through modulation of Keap1/Nrf2 signaling: Role of SMP30 in OGD/R-induced neuronal injury

2020 ◽  
pp. 096032712095424
Author(s):  
Wenxiong Liu ◽  
Haikang Zhao ◽  
Yuqiang Su ◽  
Kefeng Wang ◽  
Jing Li ◽  
...  
Keyword(s):  
Cerebral Ischemia ◽  
Ischemia Reperfusion Injury ◽  
Neuronal Survival ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
Oxygen Glucose Deprivation ◽  
Marker Protein ◽  
Cerebral Ischemia Reperfusion ◽  
Cerebral Ischemia Reperfusion Injury

Senescence marker protein 30 (SMP30) is a senescence marker molecule and identified as a calcium regulatory protein. Currently, SMP30 has emerged as a cytoprotective protein in a wide range of cell types. However, the role of SMP30 in regulating neuronal survival during cerebral ischemia/reperfusion injury remains unclear. In the present study, we aimed to investigate the biological function and regulatory mechanism of SMP30 on neuronal survival using a cellular model induced by oxygen-glucose deprivation/reoxygenation (OGD/R). The results showed that SMP30 expression was significantly decreased by OGD/R exposure in neurons. Functional experiments demonstrated that SMP30 overexpression significantly rescued the decreased cell viability and attenuated the apoptosis and reactive oxygen species generation in OGD/R-exposed neurons. By contrast, SMP30 knockdown exhibited the opposite effect. Mechanism research revealed that SMP30 overexpression contributed to the activation of nuclear factor erythroid 2-related factor (Nrf2)/antioxidant response element (ARE) signaling associated with downregulation of Kelch-like ECH-associated protein (Keap1). Keap1 overexpression or Nrf2 silencing significantly reversed SMP30-mediated neuroprotection against OGD/R-induced injury. Overall, these findings demonstrate that SMP30 overexpression protects neurons from OGD/R-induced apoptosis and oxidative stress by enhancing Nrf2/ARE antioxidant signaling via inhibition of Keap1. These data highlight the importance of the SMP30/Keap1/Nrf2/ARE signaling axis in regulating neuronal survival during cerebral ischemia/reperfusion injury.

Role of Oxidative Insult and Neuronal Survival in Alzheimer’s and Parkinson’s Diseases

2007 ◽  
pp. 133-148
Author(s):  
Akihiko Nunomura ◽  
Paula I. Moreira ◽  
Xiongwei Zhu ◽  
Adam D. Cash ◽  
Mark A. Smith ◽  
...  
Keyword(s):  
Neuronal Survival ◽  
Parkinson’S Diseases ◽  
Oxidative Insult

scholarly journals Role of Nogo-A in Neuronal Survival in the Reperfused Ischemic Brain

2010 ◽  
Vol 30 (5) ◽  
pp. 969-984 ◽  
Author(s):  
Ertugrul Kilic ◽  
Ayman ElAli ◽  
Ülkan Kilic ◽  
Zeyun Guo ◽  
Milas Ugur ◽  
...  
Keyword(s):  
P38 Mapk ◽  
Brain Plasticity ◽  
Focal Cerebral Ischemia ◽  
Neuronal Survival ◽  
Coiled Coil ◽  
Direct Interaction ◽  
Neutralizing Antibody ◽  
Neurologic Recovery ◽  
Tensin Homolog

Nogo-A is an oligodendroglial neurite outgrowth inhibitor, the deactivation of which enhances brain plasticity and functional recovery in animal models of stroke. Nogo-A's role in the reperfused brain tissue was still unknown. By using Nogo-A−/− mice and mice in which Nogo-A was blocked with a neutralizing antibody (11C7) that was infused into the lateral ventricle or striatum, we show that Nogo-A inhibition goes along with decreased neuronal survival and more protracted neurologic recovery, when deactivation is constitutive or induced 24 h before, but not after focal cerebral ischemia. We show that in the presence of Nogo-A, RhoA is activated and Rac1 and RhoB are deactivated, maintaining stress kinases p38/MAPK, SAPK/JNK1/2 and phosphatase-and-tensin homolog (PTEN) activities low. Nogo-A blockade leads to RhoA deactivation, thus overactivating Rac1 and RhoB, the former of which activates p38/MAPK and SAPK/JNK1/2 via direct interaction. RhoA and its effector Rho-associated coiled-coil protein kinase2 deactivation in turn stimulates PTEN, thus inhibiting Akt and ERK1/2, and initiating p53-dependent cell death. Our data suggest a novel role of Nogo-A in promoting neuronal survival by controlling Rac1/RhoA balance. Clinical trials should be aware of injurious effects of axonal growth-promoting therapies. Thus, Nogo-A antibodies should not be used in the very acute stroke phase.

NMDA receptor activity determines neuronal fate: location or number?

2015 ◽  
Vol 26 (1) ◽  
Author(s):  
Xianju Zhou ◽  
Zhouyou Chen ◽  
Wenwei Yun ◽  
Hongbing Wang
Keyword(s):  
Neuronal Death ◽  
Neuronal Damage ◽  
Neuronal Survival ◽  
Neurological Diseases ◽  
Synaptic Activity ◽  
Neuronal Fate ◽  
Mutual Antagonism ◽  
Nmdar Activation ◽  
Excessive Activation

AbstractIt is widely believed that the proper activation of N-methyl-D-aspartate (NMDA) receptors (NMDARs) promotes neuronal survival, whereas an excessive activation of NMDARs leads to neuronal damage. NMDARs are found at both synaptic and extrasynaptic sites. One current prevailing theory proposes the dichotomy of NMDAR activity. The role of the two population receptors is mutual antagonism. The activation of synaptic NMDARs, such as synaptic activity at physiological levels, promotes neuronal survival. However, the activation of extrasynaptic NMDARs occurring during stroke, brain injury, and chronic neurological diseases contributes to neuronal death. Thus, the location of NMDARs determines the neuronal fate. However, the theory is greatly challenged. Several studies suggested that synaptic NMDARs are involved in neuronal death. Recently, our work further showed that the coactivation of synaptic and extrasynaptic NMDARs contributes to neuronal death under neuronal insults. Therefore, we propose that the magnitude and duration of NMDAR activation determines the neuronal fate. More interestingly, there appears to be some subtle differences in the affinity between synaptic and extrasynaptic NMDARs, shedding light on the development of selective drugs to block extrasynaptic NMDARs.

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