mTORC1 inhibition attenuates necroptosis through RIP1 inhibition-mediated TFEB activation.
Animals
Autophagy
/ drug effects
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
/ metabolism
Cardiotonic Agents
/ pharmacology
Cell Line
Mechanistic Target of Rapamycin Complex 1
/ antagonists & inhibitors
Myocytes, Cardiac
/ cytology
Necroptosis
/ drug effects
Protein Kinase Inhibitors
/ pharmacology
Protein Serine-Threonine Kinases
/ metabolism
Rats
Receptor-Interacting Protein Serine-Threonine Kinases
Sirolimus
/ pharmacology
Autophagy
Necroptosis
RIP1
Rapamycin
TNF-α
mTOR
Journal
Biochimica et biophysica acta. Molecular basis of disease
ISSN: 1879-260X
Titre abrégé: Biochim Biophys Acta Mol Basis Dis
Pays: Netherlands
ID NLM: 101731730
Informations de publication
Date de publication:
01 12 2019
01 12 2019
Historique:
received:
14
04
2019
revised:
22
08
2019
accepted:
04
09
2019
pubmed:
10
9
2019
medline:
30
5
2020
entrez:
10
9
2019
Statut:
ppublish
Résumé
Accumulating evidence indicates that necroptosis contributes to cardiovascular diseases. We recently reported suppression of autophagy by necroptotic signals in cardiomyocytes and protective action of rapamycin. Here we examined the mechanism by which mTORC1 inhibition protects cardiomyocytes from necroptosis. Necroptosis of H9c2 cells was induced by treatment with tumor necrotic factor-α (TNF) and z-VAD-fmk (zVAD), and the extent of necroptosis was determined as the level of LDH release (as % of total). TNF/zVAD increased RIP1-RIP3 interaction and LDH release from 3.4 ± 1.3% to 46.1 ± 2.3%. The effects of TNF/zVAD were suppressed by an mTORC1 inhibitor, rapamycin, and an mTORC1/2 inhibitor, Ku-0063794, but not by a p70s6K inhibitor, PF-4708671. Protection by rapamycin was not abolished by inhibitors of TAK1, IKKα/β, and cIAP, endogenous necroptosis suppressors upstream of RIP1. Rapamycin and Ku-0063794 suppressed TNF/zVAD-induced RIP1-Ser166 phosphorylation and increased phosphorylation of RIP1-Ser320, an inhibitory phosphorylation site, though such an effect on RIP1-Ser320 was not observed for PF-4708671. Protective effects of rapamycin on TNF/zVAD-induced RIP1-RIP3 binding and necroptosis were undetected in cells transfected with RIP1-S320A. In TNF/zVAD-treated cells, rapamycin and a RIP1 inhibitor, necrostatin-1, increased nuclear localization of transcriptional factor EB (TFEB) and promoted autolysosome formation from autophagosomes in a TFEB-dependent manner. Knockdown of TFEB expression attenuated rapamycin-induced protection from necroptosis in TNF/zVAD-treated cells. The results suggest that mTORC1 inhibition promotes autophagy and protects cardiomyocytes from necroptosis by a TFEB-dependent mechanism and that inhibition of RIP1 by increased phosphorylation at Ser320 is crucial in the cardiomyocyte protection afforded by mTORC1 inhibition.
Identifiants
pubmed: 31499159
pii: S0925-4439(19)30275-3
doi: 10.1016/j.bbadis.2019.165552
pii:
doi:
Substances chimiques
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
0
Cardiotonic Agents
0
Protein Kinase Inhibitors
0
TFEB protein, rat
0
Mechanistic Target of Rapamycin Complex 1
EC 2.7.11.1
Protein Serine-Threonine Kinases
EC 2.7.11.1
RIPK1 protein, rat
EC 2.7.11.1
Receptor-Interacting Protein Serine-Threonine Kinases
EC 2.7.11.1
Sirolimus
W36ZG6FT64
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
165552Informations de copyright
Copyright © 2019 The Author(s). Published by Elsevier B.V. All rights reserved.