Linked Life Data

19606063

Source:http://linkedlifedata.com/resource/pubmed/id/19606063

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2009-7-31
pubmed:abstractText
Experimental reduction of neprilysin (NEP) or insulin-degrading enzyme (IDE) in vivo exacerbates beta-amyloid accumulation in the brain. The level of these enzymes is reportedly reduced during aging and in postmortem brains of patients with sporadic Alzheimer disease (AD). To distinguish between primary decreases in NEP and IDE activity that might contribute to beta-amyloid accumulation and decreases secondary to neurodegenerative changes in AD, we measured NEP and IDE levels by indirect sandwich ELISA and enzyme activities by immunocapture-based fluorogenic assays in postmortem frontal cortex from patients of different ages and at different pathological stages of AD, as indicated by Braak tangle stage. The ELISA measurements of neuron-specific enolase were used to adjust for neuronal loss. Both unadjusted and neuron-specific enolase-adjusted NEP levels and activity were significantly increased in AD and positively correlated with Braak stage but negatively with age in AD patients. Insulin-degrading enzyme activity was higher in AD than controls; this was significant after adjustment for neuron-specific enolase level; unadjusted IDE protein level was decreased in AD but not after adjustment. Our findings suggest that reduction in NEP and IDE activity is not the primary cause of beta-amyloid accumulation in AD, but rather a late-stage phenomenon secondary to neurodegeneration.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-3069
pubmed:author
pubmed:issnType
Print
pubmed:volume
68
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
902-14
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Neprilysin and insulin-degrading enzyme levels are increased in Alzheimer disease in relation to disease severity.
pubmed:affiliation
Dementia Research Group, Clinical Science at North Bristol, University of Bristol, Frenchay Hospital, Frenchay, Bristol, United Kingdom. scott.miners@bristol.ac.uk
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't