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cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion

We have reported that conventional protein kinase Cγ (cPKCγ)-modulated neuron-specific autophagy improved the neurological outcome of mice following ischemic stroke through the Akt-mechanistic target of rapamycin (mTOR) pathway. However, its detailed molecular mechanism remains unclear. In this stud...

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Autores principales: Hua, Rongrong, Han, Song, Zhang, Nan, Dai, Qingqing, Liu, Ting, Li, Junfa
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5983661/
https://www.ncbi.nlm.nih.gov/pubmed/29734780
http://dx.doi.org/10.3390/ijms19051380
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author Hua, Rongrong
Han, Song
Zhang, Nan
Dai, Qingqing
Liu, Ting
Li, Junfa
author_facet Hua, Rongrong
Han, Song
Zhang, Nan
Dai, Qingqing
Liu, Ting
Li, Junfa
author_sort Hua, Rongrong
collection PubMed
description We have reported that conventional protein kinase Cγ (cPKCγ)-modulated neuron-specific autophagy improved the neurological outcome of mice following ischemic stroke through the Akt-mechanistic target of rapamycin (mTOR) pathway. However, its detailed molecular mechanism remains unclear. In this study, primary cortical neurons from postnatal one-day-old C57BL/6J cPKCγ wild-type (cPKCγ(+/+)) and knockout (cPKCγ(−/−)) mice suffering oxygen glucose deprivation/reperfusion (OGD/R) were used to simulate ischemia/reperfusion injury in vitro. A block of autophagic flux was observed in cPKCγ(+/+) neurons under OGD/R exposure, characterized by accumulation of p62. Immunofluorescent results showed a decrease in colocalization between LC3 and Atg14 or Stx17 in cPKCγ(+/+) neurons when compared with cPKCγ(−/−) neurons after OGD/R. However, the colocalization between LC3 and Lamp2 was barely decreased, indicating the presence of autolysosomes. The larger lysotracker-positive structures were also significantly increased. These results suggest that cPKCγ-induced inhibition of autophagy occurred at the stages of autophagosome formation, Stx17 anchoring, and the degradation of autolysosomes in particular. In addition, cPKCγ-modulated phosphorylation of mTOR at Ser 2481 was dependent on the site of Ser 2448, which may have blocked autophagic flux. cPKCγ-modulated sequential reactivation of mTOR inhibited autophagic flux in neurons exposed to OGD/R, which may provide endogenous interventional strategies for stroke, especially ischemia/reperfusion injury.
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spelling pubmed-59836612018-06-05 cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion Hua, Rongrong Han, Song Zhang, Nan Dai, Qingqing Liu, Ting Li, Junfa Int J Mol Sci Article We have reported that conventional protein kinase Cγ (cPKCγ)-modulated neuron-specific autophagy improved the neurological outcome of mice following ischemic stroke through the Akt-mechanistic target of rapamycin (mTOR) pathway. However, its detailed molecular mechanism remains unclear. In this study, primary cortical neurons from postnatal one-day-old C57BL/6J cPKCγ wild-type (cPKCγ(+/+)) and knockout (cPKCγ(−/−)) mice suffering oxygen glucose deprivation/reperfusion (OGD/R) were used to simulate ischemia/reperfusion injury in vitro. A block of autophagic flux was observed in cPKCγ(+/+) neurons under OGD/R exposure, characterized by accumulation of p62. Immunofluorescent results showed a decrease in colocalization between LC3 and Atg14 or Stx17 in cPKCγ(+/+) neurons when compared with cPKCγ(−/−) neurons after OGD/R. However, the colocalization between LC3 and Lamp2 was barely decreased, indicating the presence of autolysosomes. The larger lysotracker-positive structures were also significantly increased. These results suggest that cPKCγ-induced inhibition of autophagy occurred at the stages of autophagosome formation, Stx17 anchoring, and the degradation of autolysosomes in particular. In addition, cPKCγ-modulated phosphorylation of mTOR at Ser 2481 was dependent on the site of Ser 2448, which may have blocked autophagic flux. cPKCγ-modulated sequential reactivation of mTOR inhibited autophagic flux in neurons exposed to OGD/R, which may provide endogenous interventional strategies for stroke, especially ischemia/reperfusion injury. MDPI 2018-05-06 /pmc/articles/PMC5983661/ /pubmed/29734780 http://dx.doi.org/10.3390/ijms19051380 Text en © 2018 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Hua, Rongrong
Han, Song
Zhang, Nan
Dai, Qingqing
Liu, Ting
Li, Junfa
cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion
title cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion
title_full cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion
title_fullStr cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion
title_full_unstemmed cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion
title_short cPKCγ-Modulated Sequential Reactivation of mTOR Inhibited Autophagic Flux in Neurons Exposed to Oxygen Glucose Deprivation/Reperfusion
title_sort cpkcγ-modulated sequential reactivation of mtor inhibited autophagic flux in neurons exposed to oxygen glucose deprivation/reperfusion
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5983661/
https://www.ncbi.nlm.nih.gov/pubmed/29734780
http://dx.doi.org/10.3390/ijms19051380
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