Glutamate dehydrogenase activity in leukocytes and ageing.
BACKGROUND
Glutamate dehydrogenase (GLDH) is an intracellular enzyme normally located in mitochondria and the rough endoplasmic reticulum. The metabolism of neuroexcitotoxic glutamate is lowered in many neurodegenerative disorders.


OBJECTIVE
Defining the GLDH activity in leukocytes can provide indirect data about neurodegenerative processes in the brain.


METHODS
We have developed our own method of defining the GLDH activity in leukocytes.


RESULTS
The GLDH activity was researched in the leukocytes of 130 healthy subjects (45 females, 85 males). The mean catalytic activity was 0.618 +/- 0.380 mu kat/g. The highest values were discovered in <30-year-old persons: 0.772 +/- 0.434 mu kat/g (0.712 +/- 0.406 mu kat/g in men, 0.934 +/- 0.5 mu kat/g in women). The GLDH activity decreases more slowly in the 30- to 60-year age group, yet evidently more rapidly afterwards, particularly in men, where the activity drops to 0.333 mu kat/g and in women to 0.414 mu kat/g. The older persons had a lower leukocyte GLDH activity than the younger ones (ANOVA, p = 0.000).


CONCLUSIONS
Gradual decrease in GLDH activity may be one of the key factors for neurodegenerative ageing processes.
Kravos
Matej
M
Ormoz Psychiatric Hospital, Ormoz, Slovenia. mk4@siol.net
Malesic
Ivan
I
D000328:Adult; D000375:Aging / Q000378:metabolism*; D001921:Brain / Q000201:enzymology / Q000502:physiology / Q000503:physiopathology; D002384:Catalysis; D002478:Cells, Cultured; D004789:Enzyme Activation / Q000502:physiology; D057075:Enzyme Assays / Q000379:methods*; D005260:Female; D005969:Glutamate Dehydrogenase / Q000378:metabolism*; D006801:Humans; D007962:Leukocytes / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D019636:Neurodegenerative Diseases / Q000175:diagnosis / Q000201:enzymology / Q000503:physiopathology; D012727:Sex Characteristics; D055815:Young Adult
D005969:Glutamate Dehydrogenase