N(epsilon)(gamma-glutamyl)lysine in cerebrospinal fluid marks Alzheimer type and vascular dementia.
N(epsilon)(gamma-glutamyl)lysine isodipeptide is released from the breakdown of proteins cross-linked by transglutaminase enzymes. Transglutaminase activation is a marker of apoptosis and elevated isodipeptide concentrations in body fluids might correlate with the intensity of apoptotic cell turnover. The concentration of N(epsilon)(gamma-glutamyl)lysine was measured in the cerebrospinal fluid (CSF) of patients with probable Alzheimer's disease (n = 14) and vascular type dementia (n = 11) and compared with not demented surgical controls (n = 17). Baseline levels of 26-62 nM/l (mean 37.9 +/- 8.7 SD) free isodipeptide were detected in control patients. CSF isodipeptide levels showed significant elevation in vascular (mean 95.6 +/- 45.1 SD) as well as Alzheimer patients (176.6 +/- 77.1 SD). Isodipeptide concentrations above 120 nM/l were 72% specific and 77% sensitive to Alzheimer's dementia, although the difference between the two dementias was statistically insignificant (p > 0.05). Determination of CSF N(epsilon)(gamma-glutamyl)lysine isodipeptide concentration offers a novel method for measurement of neurodegeneration in primary and mixed dementias.
Nemes
Z
Z
Department of Psychiatry, University of Debrecen, Center for Medical and Health Sciences, H-4012, Debrecen, Hungary. nemes@indi.dote.hu
Fésüs
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Egerházi
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Keszthelyi
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Degrell
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IM
D000368:Aged; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid* / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D017209:Apoptosis; D015140:Dementia, Vascular / Q000134:cerebrospinal fluid* / Q000175:diagnosis* / Q000378:metabolism / Q000473:pathology; D004151:Dipeptides / Q000134:cerebrospinal fluid* / Q000378:metabolism; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male
D004151:Dipeptides; C001299:epsilon-(gamma-glutamyl)-lysine