Association of a salivary acetylcholinesterase with Alzheimer's disease and response to cholinesterase inhibitors.
OBJECTIVE
A decrease in cholinergic activity is a key event in the biochemistry of Alzheimer's disease (AD). The aim of the study was to investigate the expression levels of markers of cholinergic function in saliva, which is a readily accessible body fluid that can be obtained from subjects with minimal distress.


METHODS
Salivary samples were obtained from people with NINCDS-ARDRA "probable" Alzheimer's disease and age- and sex-matched controls. Salivary acetylcholinesterase enzyme (AChE) activity was determined colorometrically.


RESULTS
Robust AChE catalytic activity was detected in the saliva samples that was stable for up to 6 h at room temperature following the provision of the salivary sample. The activity of the enzyme was significantly lower in people with AD than in age-matched controls. In addition, there were significant differences in activity between those who responded to acetylcholinesterase inhibitor (AChE-I) therapy and those who did not.


CONCLUSIONS
Salivary enzyme activity may therefore prove to be a useful marker of central cholinergic activity.
Sayer
Rachel
R
Dundee Alzheimer's Disease Research Centre, Department of Psychiatry, University of Dundee Medical School, Ninewells Hospital, Dundee DD1 9SY, UK.
Law
Emma
E
Connelly
Peter J
PJ
Breen
Kieran C
KC
D000110:Acetylcholinesterase / Q000032:analysis* / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000188:drug therapy / Q000201:enzymology*; D015415:Biomarkers; D002800:Cholinesterase Inhibitors / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012463:Saliva / Q000201:enzymology*
D015415:Biomarkers; D002800:Cholinesterase Inhibitors; D000110:Acetylcholinesterase