Plasma gamma-glutamyltransferase, cysteinyl-glycine, and oxidized low-density lipoprotein: a pathway associated with myocardial infarction risk?
OBJECTIVE
To investigate the interrelation between plasma γ-glutamyltransferase (GGT) activity, cysteinyl-glycine (Cys-Gly) (ie, a thiol originating from GGT-mediated cleavage of glutathione), and oxidized low-density lipoprotein (oxLDL) with regard to myocardial infarction (MI) risk in a prospective study.


RESULTS
Incident cases of MI were identified among European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam participants without prior MI during 6.0 years of follow-up. Baseline levels of Cys-Gly and oxLDL and GGT activity in plasma were measured in a case-cohort study comprising 837 subjects without incident MI and 116 subjects with incident MI. The relation of GGT, Cys-Gly and oxLDL to MI risk was assessed using Cox proportional hazards regression analysis. After adjustment for established risk factors, hazard ratios associated with a 1-SD unit increase in the log-transformed biomarker were 1.63 (95% CI, 1.30 to 2.05) for GGT, 1.36 (95% CI, 1.07 to 1.72) for Cys-Gly, and 1.37 (95% CI, 1.00 to 1.86) for oxLDL. Cys-Gly and oxLDL accounted for 2.3% of the relation between GGT and MI risk.


CONCLUSIONS
The positive association between GGT activity and MI risk appears to be independent of circulating Cys-Gly and oxLDL levels. With Cys-Gly, we found a potential new predictor of MI risk whose impact needs to be further elucidated.
Drogan
Dagmar
D
Department of Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany. drogan@dife.de
Weikert
Cornelia
C
Dierkes
Jutta
J
Klipstein-Grobusch
Kerstin
K
Buijsse
Brian
B
Möhlig
Matthias
M
Pfeiffer
Andreas F H
AF
Pischon
Tobias
T
Spranger
Joachim
J
Boeing
Heiner
H
D000328:Adult; D000368:Aged; D015331:Cohort Studies; D004151:Dipeptides / Q000097:blood*; D005260:Female; D005858:Germany; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000209:etiology*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D005723:gamma-Glutamyltransferase / Q000097:blood*
D004151:Dipeptides; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; C028505:cysteinylglycine; D005723:gamma-Glutamyltransferase