English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/62812
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:


Molecular reorganization of endocannabinoid signalling in Alzheimer's disease.

AuthorsMulder, J.; Zilberter, M.; Pasquaré, S. J.; Alpár, A.; Ferreira, S. G.; Köfalvi, A.; Martín-Moreno, Ana María; Keimpema, E.; Tanila, H.; Watanabe, M.; Mackie, K.; Hortobágyi, T.; Ceballos, María L. de ; Harkany, T.; Schulte, Gunnar
Issue Date2011
PublisherOxford University Press
CitationBrain 134(4): 1041-1060 (2011)
AbstractRetrograde messengers adjust the precise timing of neurotransmitter release from the presynapse, thus modulating synaptic efficacy and neuronal activity. 2-Arachidonoyl glycerol (2-AG), an endocannabinoid, is one such messenger produced in the postsynapse that inhibits neurotransmitter release upon activating presynaptic CB1 cannabinoid receptors (CB1Rs). Cognitive impairment in Alzheimer¿s disease (AD) is due to synaptic failure in hippocampal neuronal networks. We hypothesized that errant retrograde 2-AG signalling impairs synaptic neurotransmission in AD. Comparative protein profiling and quantitative morphometry showed that overall CB1R protein levels in the hippocampi of AD patients remain unchanged relative to age-matched controls, and CB1R+ presynapses engulf ¿-amyloid (A¿)-containing senile plaques. Hippocampal protein concentrations for sn-1-diacylglycerol lipases ¿ and ß (DAGL¿/¿), synthesizing 2-AG, significantly increase in definite AD (Braak stage VI), with ectopic DAGL¿ expression found in microglia accumulating near senile plaques and apposing CB1R+ presynapses. We find that microglia expressing two 2-AG-degrading enzymes, serine hydrolase ¿/¿-hydrolase domain-containing 6 (ABHD6) and monoacylglycerol lipase (MGL), begin to surround senile plaques in probable AD (Braak stage III). However, AD pathology differentially impacts ABHD6 and MGL in hippocampal neurons: ABHD6 expression ceases in neurofibrillary tangle-bearing pyramidal cells. In contrast, pyramidal cells containing hyperphosphorylated tau retain MGL expression, although at levels significantly lower than in neurons lacking neurofibrillary pathology. Here, MGL accumulates in CB1R+ presynapses. Subcellular fractionation revealed impaired MGL recruitment to biological membranes in post-mortem AD tissues, suggesting AD-related modifications to terminating 2-AG signalling. We have experimentally confirmed that altered 2-AG signalling could contribute to synapse silencing in AD by demonstrating significantly prolonged depolarization-induced suppression of inhibition when superfusing mouse hippocampi with A¿. We propose that the temporal dynamics and cellular specificity of molecular rearrangements impairing 2-AG availability and actions differ from those of anandamide. Thus, enhanced endocannabinoid signalling, particularly around senile plaques, can exacerbate synaptic failure in AD.
Publisher version (URL)http://dx.doi.org/10.1093/brain/awr046
Identifiersissn: 0006-8950
Appears in Collections:(IC) Artículos
Files in This Item:
File Description SizeFormat 
DeCeballos,2011,Brain,134,1041-.pdf3,41 MBAdobe PDFThumbnail
Show full item record
Review this work

Related articles:

WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.