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Neuroinflammation and A? accumulation linked to systemic inflammation are decreased by genetic PKR down-regulation.

ABSTRACT: Alzheimer's disease (AD) is a neurodegenerative disorder, marked by senile plaques composed of amyloid-? (A?) peptide, neurofibrillary tangles, neuronal loss and neuroinflammation. Previous works have suggested that systemic inflammation could contribute to neuroinflammation and enhanced A? cerebral concentrations. The molecular pathways leading to these events are not fully understood. PKR is a pro-apoptotic kinase that can trigger inflammation and accumulates in the brain and cerebrospinal fluid of AD patients. The goal of the present study was to assess if LPS-induced neuroinflammation and A? production could be altered by genetic PKR down regulation. The results show that, in the hippocampus of LPS-injected wild type mice, neuroinflammation, cytokine release and A? production are significantly increased and not in LPS-treated PKR knock-out mice. In addition BACE1 and activated STAT3 levels, a putative transcriptional regulator of BACE1, were not found increased in the brain of PKR knock-out mice as observed in wild type mice. Using PET imaging, the decrease of hippocampal metabolism induced by systemic LPS was not observed in LPS-treated PKR knock-out mice. Altogether, these findings demonstrate that PKR plays a major role in brain changes induced by LPS and could be a valid target to modulate neuroinflammation and A? production.

SUBMITTER: Carret-Rebillat AS

PROVIDER: S-EPMC4330547 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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Neuroinflammation and Aβ accumulation linked to systemic inflammation are decreased by genetic PKR down-regulation.

Carret-Rebillat Anne-Sophie AS Pace Clarisse C Gourmaud Sarah S Ravasi Laura L Montagne-Stora Samantha S Longueville Sophie S Tible Marion M Sudol Erika E Chang Raymond Chuen-Chung RC Paquet Claire C Mouton-Liger François F Hugon Jacques J

Scientific reports 20150217

Alzheimer's disease (AD) is a neurodegenerative disorder, marked by senile plaques composed of amyloid-β (Aβ) peptide, neurofibrillary tangles, neuronal loss and neuroinflammation. Previous works have suggested that systemic inflammation could contribute to neuroinflammation and enhanced Aβ cerebral concentrations. The molecular pathways leading to these events are not fully understood. PKR is a pro-apoptotic kinase that can trigger inflammation and accumulates in the brain and cerebrospinal flu ...[more]

PMID: 25687824

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Neuroinflammation and A? accumulation linked to systemic inflammation are decreased by genetic PKR down-regulation.

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Neuroinflammation and Aβ accumulation linked to systemic inflammation are decreased by genetic PKR down-regulation.

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