Bax siRNA promotes survival of cultured and allografted granule cell precursors through blockade of caspase-3 cleavage.
Transplantation of neuronal precursor cells (NPCs) into the central nervous system could represent a powerful therapeutical tool against neurodegenerative diseases. Unfortunately, numerous NPCs die shortly after transplantation, predominantly due to caspase-dependent apoptosis. Using a culture of cerebellar neuronal precursors, we have previously demonstrated protective effect of the neuropeptide PACAP, which suppresses ceramide-induced apoptosis by blockade of the mitochondrial apoptotic pathway. The main objective of this study was to determine whether Bax repression can promote survival of NPCs allotransplanted into a host animal. In vivo and ex vivo experiments revealed that C2-ceramide increases Bax expression, while PACAP reverses this effect. In vitro tests using cerebellar NPCs demonstrated that the Bax-specific small interfering RNA (siRNA) could reduce their death and caspase-3 cleavage within the first 24 h. BrdU-labelled NPCs were subjected to transfection procedure with or without siRNA introduction before using for in vivo transplantation. Twenty-four hours after, the allografted NPCs containing siRNA showed significantly reduced level of caspase-3 cleavage, and the volume of their implants was almost twofold higher than in the case of empty-transfected precursors. These data evidence an important role of Bax in life/death decision of grafted NPCs and suggest that RNA interference strategy may be applicable for maintaining NPCs survival within the critical first hours after their transplantation.
Zhokhov
S S
SS
INSERM U413, Laboratory of Cellular and Molecular Neuroendocrinology, Laboratoire International Associé Samuel de Champlain, European Institute for Peptide Research (IFRMP 23), University of Rouen, Mont-Saint-Aignan, France.
Desfeux
A
A
Aubert
N
N
Falluel-Morel
A
A
Fournier
A
A
Laudenbach
V
V
Vaudry
H
H
Gonzalez
B J
BJ
D000818:Animals; D053148:Caspase 3 / Q000378:metabolism; D061945:Caspase Inhibitors; D002470:Cell Survival; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology*; D009474:Neurons / Q000166:cytology*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000494:pharmacology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013110:Sphingosine / Q000031:analogs & derivatives / Q000494:pharmacology; D033581:Stem Cell Transplantation; D013234:Stem Cells / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D014184:Transplantation, Homologous; D051028:bcl-2-Associated X Protein / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism
D061945:Caspase Inhibitors; C064769:N-acetylsphingosine; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D034741:RNA, Small Interfering; D051028:bcl-2-Associated X Protein; D053148:Caspase 3; D013110:Sphingosine