Hypercholest erolemia and nuerodegene ration. Comparison of hippocampal phenotypes in LDLr Knockout and APPswe/Ps1de9 MICE.

 

Authors
Camins Espuny, Antonio
Format
Article
Status
publishedVersion
Description

Previous studies suggest that Alzheimer's disease (AD) neurobiology could not be explained solely by an increase in ?-amyloid levels. Recently, it has been proposed that alterations in brain cholesterol metabolism may contribute to the pathogenesis of AD. In the present work, we focus on early changes in the hippocampal phenotypes of two mouse models in which cognitive impairments were previously described: a) the hypercholesterolemic LDL receptor knockout (LDLr -/-) and b) the APPswe/PS1dE9 (APP/PS1) transgenic model of familial AD. Our initial analysis, subsequent validation and additional experiments at the mRNA and protein levels demonstrate some parallels between the hippocampal phenotypes of these 2 mouse models, however our data suggest that the molecular mechanisms leading to cognitive decline are distinct in LDLr -/- and APP/PS1 animals. Genes related to cytokine signaling were significantly down-regulated in LDLr -/- mice when compared to both the wild-type and APP/PS1 mice, and these include prostaglandin-endoperoxide synthases 1 and 2 (ptgs1 and 2) and nerve grow factor (ngf). We have also detected reduced expression of genes related to lipid metabolism in LDLr -/- mice: peroxisome proliferator activated receptor gamma (pparg), pro-opiomelanocortin-alpha (pomc) and of protein kinase, AMP-activated, alpha 1 catalytic subunit of AMPK (prkaa1). Our array data also indicate that transcriptional activity of early genes involved in memory process, such as FBJ osteosarcoma oncogene (Fos) and the activity regulated cytoskeletal-associated protein (Arc) gene, are increased in the hippocampus of LDLr -/- mice. Several proteins like insulin degrading enzyme (IDE), PGC-1?, OXPHOS 1, NMDAR1 and cyclic AMP response element binding protein (CREB) are up-regulated in the LDLr -/- mice, while in the APP/PS1 mouse model only OXPHOS complexes 2, 3 and 5 are slightly downregulated. Further studies are necessary to understand the molecular pathways involved in memory loss in hypercholesterolemic LDLr -/- mice.
Universidad Nacional de Loja
https://www.ncbi.nlm.nih.gov/pubmed/25797218

Publication Year
2015
Language
eng
Topic
APP/PS1
ALZHEIMER'S DISEASE
CHOLESTEROL
HIPPOCAMPUS
LDLR?/?
OXPHOS
Repository
Repositorio SENESCYT
Get full text
http://repositorio.educacionsuperior.gob.ec/handle/28000/3034
Rights
openAccess
License
restrictedAccess