title: Wide-ranging alterations in the brain fatty acid complement of subjects with late Alzheimer's disease as detected by GC-MS.
abstract: Disturbed lipid metabolism is a well-established feature of human Alzheimer's disease (AD). The present study used gas chromatography-mass spectrometry (GC-MS) analysis of fatty acid methyl esters (FAMES) to profile all detectable fatty acid (FA) species present in post-mortem neocortical tissue (Brodmann 7 region). Quantitative targeted analysis was undertaken from 29 subjects (n=15 age-matched controls; n=14 late-stage AD). GC-MS analysis of FAMES detected a total of 24 FAs and of these, 20 were fully quantifiable. The results showed significant and wide ranging elevations in AD brain FA concentrations. A total of 9 FAs were elevated in AD with cis-13,16-docosenoic acid increased most (170%; P=0.033). Intriguingly, docosahexanoic acid (DHA; C22:6) concentrations were elevated (47%; P=0.018) which conflicts with the findings of others (unaltered or decreased) in some brain regions after the onset of AD. Furthermore, our results appear to indicate that subject gender influences brain FA levels in AD subjects (but not in age-matched control subjects). Among AD subjects 7 FA species were significantly higher in males than in females. These preliminary findings pinpoint FA disturbances as potentially important in the pathology of AD. Further work is required to determine if such changes are influenced by disease severity or different types of dementia.
authors.affiliation: Institute for Global Food Security (IGFS), Queen's University Belfast Stranmillis Road, Belfast Northern Ireland, BT9 6AG, UK.
authors.forename: Muhammad Luqman
authors.initials: ML
authors.lastname: Nasaruddin
authors.affiliation: Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University Lancaster LA1 4YQ, UK.
authors.forename: Christian
authors.initials: C
authors.lastname: Hölscher
authors.affiliation: Dementia Research Group, Institute of Clinical Neurosciences, School of Clinical Sciences, University of Bristol, Frenchay Hospital Bristol, UK.
authors.forename: Patrick
authors.initials: P
authors.lastname: Kehoe
authors.affiliation: Beaumont Research Institute, Beaumont Health 3811 West 13 Mile Road, Royal Oak, Michigan 48073, USA.
authors.forename: Stewart Francis
authors.initials: SF
authors.lastname: Graham
authors.affiliation: Institute for Global Food Security (IGFS), Queen's University Belfast Stranmillis Road, Belfast Northern Ireland, BT9 6AG, UK.
authors.forename: Brian Desmond
authors.initials: BD
authors.lastname: Green
keywords: AD; DHA; Fatty acid; GC-MS; brain tissues