Hippocampal glutamate-glutamine (Glx) in adults with Down syndrome: a preliminary study using in vivo proton magnetic resonance spectroscopy (1H MRS)

Hdl Handle:
http://hdl.handle.net/10147/560465
Title:
Hippocampal glutamate-glutamine (Glx) in adults with Down syndrome: a preliminary study using in vivo proton magnetic resonance spectroscopy (1H MRS)
Authors:
Tan, Giles MY; Beacher, Felix; Daly, Eileen; Horder, Jamie; Prasher, Verinder; Hanney, Maria-Luisa; Morris, Robin; Lovestone, Simon; Murphy, Kieran C; Simmons, Andrew; Murphy, Declan GM
Citation:
Journal of Neurodevelopmental Disorders. 2014 Nov 27;6(1):42
Issue Date:
27-Nov-2014
URI:
http://dx.doi.org/10.1186/1866-1955-6-42; http://hdl.handle.net/10147/560465
Abstract:
Abstract Background Down syndrome (DS), or trisomy 21, is one of the most common autosomal mutations. People with DS have intellectual disability (ID) and are at significantly increased risk of developing Alzheimer’s disease (AD). The biological associates of both ID and AD in DS are poorly understood, but glutamate has been proposed to play a key role. In non-DS populations, glutamate is essential to learning and memory and glutamate-mediated excitotoxicity has been implicated in AD. However, the concentration of hippocampal glutamate in DS individuals with and without dementia has not previously been directly investigated. Proton magnetic resonance spectroscopy (1H MRS) can be used to measure in vivo the concentrations of glutamate-glutamine (Glx). The objective of the current study was to examine the hippocampal Glx concentration in non-demented DS (DS-) and demented DS (DS+) individuals. Methods We examined 46 adults with DS (35 without dementia and 11 with dementia) and 39 healthy controls (HC) using 1H MRS and measured their hippocampal Glx concentrations. Results There was no significant difference in the hippocampal Glx concentration between DS+ and DS-, or between either of the DS groups and the healthy controls. Also, within DS, there was no significant correlation between hippocampal Glx concentration and measures of overall cognitive ability. Last, a sample size calculation based on the effect sizes from this study showed that it would have required 6,257 participants to provide 80% power to detect a significant difference between the groups which would indicate that there is a very low likelihood of a type 2 error accounting for the findings in this study. Conclusions Individuals with DS do not have clinically detectable differences in hippocampal Glx concentration. Other pathophysiological processes likely account for ID and AD in people with DS.
Language:
en
Keywords:
DOWN'S SYNDROME; DEVELOPMENTAL DISORDERS

Full metadata record

DC FieldValue Language
dc.contributor.authorTan, Giles MYen
dc.contributor.authorBeacher, Felixen
dc.contributor.authorDaly, Eileenen
dc.contributor.authorHorder, Jamieen
dc.contributor.authorPrasher, Verinderen
dc.contributor.authorHanney, Maria-Luisaen
dc.contributor.authorMorris, Robinen
dc.contributor.authorLovestone, Simonen
dc.contributor.authorMurphy, Kieran Cen
dc.contributor.authorSimmons, Andrewen
dc.contributor.authorMurphy, Declan GMen
dc.date.accessioned2015-07-15T09:25:55Zen
dc.date.available2015-07-15T09:25:55Zen
dc.date.issued2014-11-27en
dc.identifier.citationJournal of Neurodevelopmental Disorders. 2014 Nov 27;6(1):42en
dc.identifier.urihttp://dx.doi.org/10.1186/1866-1955-6-42en
dc.identifier.urihttp://hdl.handle.net/10147/560465en
dc.description.abstractAbstract Background Down syndrome (DS), or trisomy 21, is one of the most common autosomal mutations. People with DS have intellectual disability (ID) and are at significantly increased risk of developing Alzheimer’s disease (AD). The biological associates of both ID and AD in DS are poorly understood, but glutamate has been proposed to play a key role. In non-DS populations, glutamate is essential to learning and memory and glutamate-mediated excitotoxicity has been implicated in AD. However, the concentration of hippocampal glutamate in DS individuals with and without dementia has not previously been directly investigated. Proton magnetic resonance spectroscopy (1H MRS) can be used to measure in vivo the concentrations of glutamate-glutamine (Glx). The objective of the current study was to examine the hippocampal Glx concentration in non-demented DS (DS-) and demented DS (DS+) individuals. Methods We examined 46 adults with DS (35 without dementia and 11 with dementia) and 39 healthy controls (HC) using 1H MRS and measured their hippocampal Glx concentrations. Results There was no significant difference in the hippocampal Glx concentration between DS+ and DS-, or between either of the DS groups and the healthy controls. Also, within DS, there was no significant correlation between hippocampal Glx concentration and measures of overall cognitive ability. Last, a sample size calculation based on the effect sizes from this study showed that it would have required 6,257 participants to provide 80% power to detect a significant difference between the groups which would indicate that there is a very low likelihood of a type 2 error accounting for the findings in this study. Conclusions Individuals with DS do not have clinically detectable differences in hippocampal Glx concentration. Other pathophysiological processes likely account for ID and AD in people with DS.-
dc.language.isoenen
dc.subjectDOWN'S SYNDROMEen
dc.subjectDEVELOPMENTAL DISORDERSen
dc.titleHippocampal glutamate-glutamine (Glx) in adults with Down syndrome: a preliminary study using in vivo proton magnetic resonance spectroscopy (1H MRS)en
dc.language.rfc3066en-
dc.rights.holderGiles MY Tan et al.; licensee BioMed Central Ltd.-
dc.description.statusPeer Reviewed-
dc.date.updated2014-12-11T20:50:29Z-
All Items in Lenus, The Irish Health Repository are protected by copyright, with all rights reserved, unless otherwise indicated.