Please use this identifier to cite or link to this item:
Title: Anandamide Effects in a Streptozotocin-Induced Alzheimer's Disease-Like Sporadic Dementia in Rats
Authors: Moreira-Silva, Daniel
Carrettiero, Daniel C.
Oliveira, Adriele S. A.
Rodrigues, Samanta
Dos Santos-Lopes, Joyce
Canas, Paula M. 
Cunha, Rodrigo A. 
Almeida, Maria C.
Ferreira, Tatiana L.
Keywords: endocannabinoid; CB1; HSP70; BAG2; phosphorylated tau; fear conditioning; object recognition memory; prepulse inhibition
Issue Date: 2018
Publisher: Frontiers Media S.A.
Project: São Paulo Research Foundation–FAPESP (graduate fellowship grants 2014/14661-1 and 2016/24773-7 to DM-S and research grants 2015/02991- 0 to MA and 2015/23426-9 to DC) 
CNPq (research grant 429894/2016-3 to TF and 449102/2014-9 to DC) 
Maratona da Saúde 
GAI-FMUC and Banco Santander-Totta 
Santa Casa da Misericórdia 
CENTRO-01-0145-FEDER- 000008:BrainHealth 2020 
POCI-01- 0145-FEDER-007440 
Serial title, monograph or event: Frontiers in Neuroscience
Volume: 12
Issue: SEP
Abstract: Alzheimer's disease (AD) is characterized by multiple cognitive deficits including memory and sensorimotor gating impairments as a result of neuronal and synaptic loss. The endocannabinoid system plays an important role in these deficits but little is known about its influence on the molecular mechanism regarding phosphorylated tau (p-tau) protein accumulation - one of the hallmarks of AD -, and on the density of synaptic proteins. Thus, the aim of this study was to investigate the preventive effects of anandamide (N-arachidonoylethanolamine, AEA) on multiple cognitive deficits and on the levels of synaptic proteins (syntaxin 1, synaptophysin and synaptosomal-associated protein, SNAP-25), cannabinoid receptor type 1 (CB1) and molecules related to p-tau degradation machinery (heat shock protein 70, HSP70), and Bcl2-associated athanogene (BAG2) in an AD-like sporadic dementia model in rats using intracerebroventricular (icv) injection of streptozotocin (STZ). Our hypothesis is that AEA could interact with HSP70, modulating the level of p-tau and synaptic proteins, preventing STZ-induced cognitive impairments. Thirty days after receiving bilateral icv injections of AEA or STZ or both, the cognitive performance of adult male Wistar rats was evaluated in the object recognition test, by the escape latency in the elevated plus maze (EPM), by the tone and context fear conditioning as well as in prepulse inhibition tests. Subsequently, the animals were euthanized and their brains were removed for histological analysis or for protein quantification by Western Blotting. The behavioral results showed that STZ impaired recognition, plus maze and tone fear memories but did not affect contextual fear memory and prepulse inhibition. Moreover, AEA prevented recognition and non-associative emotional memory impairments induced by STZ, but did not influence tone fear conditioning. STZ increased the brain ventricular area and this enlargement was prevented by AEA. Additionally, STZ reduced the levels of p-tau (Ser199/202) and increased p-tau (Ser396), although AEA did not affect these alterations. HSP70 was found diminished only by STZ, while BAG2 levels were decreased by STZ and AEA. Synaptophysin, syntaxin and CB1 receptor levels were reduced by STZ, but only syntaxin was recovered by AEA. Altogether, albeit AEA failed to modify some AD-like neurochemical alterations, it partially prevented STZ-induced cognitive impairments, changes in synaptic markers and ventricle enlargement. This study showed, for the first time, that the administration of an endocannabinoid can prevent AD-like effects induced by STZ, boosting further investigations about the modulation of endocannabinoid levels as a therapeutic approach for AD.
ISSN: 1662-4548
DOI: 10.3389/fnins.2018.00653
Rights: openAccess
Appears in Collections:FMUC Medicina - Artigos em Revistas Internacionais
I&D CNC - Artigos em Revistas Internacionais

Show full item record

Page view(s)

checked on Nov 28, 2023


checked on Nov 28, 2023

Google ScholarTM




This item is licensed under a Creative Commons License Creative Commons