Intestinal glutaminase activity is increased in liver cirrhosis and correlates with minimal hepatic encephalopathy.
OBJECTIVE
We performed the current study to assess the intestinal activity of enterocyte phosphate-activated glutaminase (PAG) in cirrhosis.


METHODS
Forty-nine cirrhotic patients and 36 control subjects underwent endoscopic duodenal biopsies. Minimal hepatic encephalopathy (MHE) was evaluated using three psychometric tests. Oral glutamine challenge (OGC) was performed and MELD, Child-Pugh and the presence of esophageal varices were recorded. PAG was measured by enzymatic methods. Cerebral magnetic resonance spectroscopy was performed in 10 cirrhotics.


RESULTS
PAG was found to be higher in cirrhotics than control subjects 2.4+/-1.51 vs. 0.68+/-0.57IU/mg protein (P<0.001). PAG was also increased in patients with MHE and correlated with MELD, INR, esophageal varices and serum bile acids. A negative correlation was observed between PAG activity and intra-cerebral choline/creatine ratio (r=-0.67; P=0.035) and a positive correlation with glutamine plus glutamate/creatine ratio (r=0.78; P=0.007). In multivariate analysis using backward logistic regression, presence of MHE was the only variable independently related to altered enterocyte PAG.


CONCLUSIONS
Enterocyte PAG is increased in cirrhotic patients and correlates with MHE. These data support a possible role for intestinal glutaminase in the pathogenesis of hepatic encephalopathy (HE) and could be a new target for future therapies.
Romero-Gómez
Manuel
M
Hepatology Unit, Hospital Universitario de Valme, Ctra Cádiz s/n, 41014 Sevilla, Spain. mromerog@supercable.es
Ramos-Guerrero
Rosa
R
Grande
Lourdes
L
de Terán
Laura Collantes
LC
Corpas
Raquel
R
Camacho
Inés
I
Bautista
Juan D
JD
D000328:Adult; D005260:Female; D005972:Glutaminase / Q000378:metabolism*; D006501:Hepatic Encephalopathy / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007422:Intestines / Q000201:enzymology*; D008103:Liver Cirrhosis / Q000378:metabolism* / Q000473:pathology / Q000503:physiopathology; D016015:Logistic Models; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011168:Portal System / Q000503:physiopathology; D011594:Psychometrics; D012720:Severity of Illness Index
D005972:Glutaminase