Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P36957 (
KGDHC
)
17
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We measured the activity of the alpha-ketoglutarate dehydrogenase complex (alpha-KGDHC), a rate-limiting Krebs cycle enzyme, in postmortem brain samples from 38 controls and 30 neuropathologically confirmed Alzheimer's disease (AD) cases, in both the presence and absence of thiamine pyrophosphate (TPP), the enzyme's cofactor. Statistically significant correlations between brain pH and lactate levels and alpha-
KGDHC
activity in the controls were observed, suggesting an influence of agonal status on the activity of alpha-
KGDHC
. As compared with the controls, mean alpha-
KGDHC
activity, with added TPP, was significantly (p < 0.005) reduced in AD brain in frontal (-56%), temporal (-60%), and parietal (-68%) cortices, with the reductions (-25 to -53%) in the occipital cortex, hippocampus, amygdala, and caudate failing to reach statistical significance. In the absence of exogenously administered TPP, mean alpha-
KGDHC
activity was reduced to a slightly greater extent in all seven AD brain areas (-39 to -83%), with the reductions now reaching statistical significance in the four cerebral cortical areas and hippocampus. A statistically significant negative correlation was observed between alpha-
KGDHC
activity and neurofibrillary tangle count in AD parietal cortex, the brain area exhibiting the most marked reduction in enzyme activity; this suggests that the enzyme activity reduction in AD brain may be related to the disease process and severity. In each brain area examined, TPP produced a greater stimulatory effect on alpha-
KGDHC
activity in the AD group (23-280% mean stimulation) as compared with the controls (-4 to +50%); this TPP effect could be explained by reduced endogenous TPP levels in AD brain.(ABSTRACT TRUNCATED AT 250 WORDS)
J Neurochem 1993
Dec
PMID:Brain alpha-ketoglutarate dehydrogenase complex activity in Alzheimer's disease. 824 57