title: Plasma gamma-glutamyltransferase, cysteinyl-glycine, and oxidized low-density lipoprotein: a pathway associated with myocardial infarction risk?
abstract: 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.
authors.affiliation: Department of Epidemiology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany. drogan@dife.de
authors.forename: Dagmar
authors.initials: D
authors.lastname: Drogan
authors.forename: Cornelia
authors.initials: C
authors.lastname: Weikert
authors.forename: Jutta
authors.initials: J
authors.lastname: Dierkes
authors.forename: Kerstin
authors.initials: K
authors.lastname: Klipstein-Grobusch
authors.forename: Brian
authors.initials: B
authors.lastname: Buijsse
authors.forename: Matthias
authors.initials: M
authors.lastname: Möhlig
authors.forename: Andreas F H
authors.initials: AF
authors.lastname: Pfeiffer
authors.forename: Tobias
authors.initials: T
authors.lastname: Pischon
authors.forename: Joachim
authors.initials: J
authors.lastname: Spranger
authors.forename: Heiner
authors.initials: H
authors.lastname: Boeing
mesh_terms: 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*
chemical_list: D004151:Dipeptides; D008077:Lipoproteins, LDL; C099252:oxidized low density lipoprotein; C028505:cysteinylglycine; D005723:gamma-Glutamyltransferase