Beclin 1-independent autophagy contributes to apoptosis in cortical neurons.

Details

Ressource 1Download: BIB_42074C89EA01.P001.pdf (25358.55 [Ko])
State: Public
Version: author
Serval ID
serval:BIB_42074C89EA01
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Beclin 1-independent autophagy contributes to apoptosis in cortical neurons.
Journal
Autophagy
Author(s)
Grishchuk Y., Ginet V., Truttmann A.C., Clarke P.G., Puyal J.
ISSN
1554-8635 (Electronic)
ISSN-L
1554-8627
Publication state
Published
Issued date
2011
Peer-reviewed
Oui
Volume
7
Number
10
Pages
1115-1131
Language
english
Abstract
Neuronal autophagy is enhanced in many neurological conditions, such as cerebral ischemia and traumatic brain injury, but its role in associated neuronal death is controversial, especially under conditions of apoptosis. We therefore investigated the role of autophagy in the apoptosis of primary cortical neurons treated with the widely used and potent pro-apoptotic agent, staurosporine (STS). Even before apoptosis, STS enhanced autophagic flux, as shown by increases in autophagosomal (LC3-II level, LC3 punctate labeling) and lysosomal (cathepsin D, LAMP1, acid phosphatase, β-hexasominidase) markers. Inhibition of autophagy by 3-methyladenine, or by lentivirally-delivered shRNAs against Atg5 and Atg7, strongly reduced the STS-induced activation of caspase-3 and nuclear translocation of AIF, and gave partial protection against neuronal death. Pan-caspase inhibition with Q-VD-OPH likewise protected partially against neuronal death, but failed to affect autophagy. Combined inhibition of both autophagy and caspases gave strong synergistic neuroprotection. The autophagy contributing to apoptosis was Beclin 1-independent, as shown by the fact that Beclin 1 knockdown failed to reduce it but efficiently reduced rapamycin-induced autophagy. Moreover the Beclin 1 knockdown sensitized neurons to STS-induced apoptosis, indicating a cytoprotective role of Beclin 1 in cortical neurons. Caspase-3 activation and pyknosis induced by two other pro-apoptotic stimuli, MK801 and etoposide, were likewise found to be associated with Beclin 1-independent autophagy and reduced by the knockdown of Atg7 but not Beclin 1. In conclusion, Beclin 1-independent autophagy is an important contributor to both the caspase-dependent and -independent components of neuronal apoptosis and may be considered as an important therapeutic target in neural conditions involving apoptosis.
Pubmed
Web of science
Open Access
Yes
Create date
21/10/2011 10:16
Last modification date
20/08/2019 13:43
Usage data