title: Pharmacologically dosed oral glutamine reduces myocardial injury in patients undergoing cardiac surgery: a randomized pilot feasibility trial.
abstract: OBJECTIVE
  Glutamine (GLN) has been shown to protect against in vitro and in vivo myocardial injury. In humans, perioperative ischemia/reperfusion (I/R) injury during cardiac surgery is associated with higher morbidity and mortality. The objective of this safety and feasibility pilot trial was to determine if pharmacologically dosed, preoperative oral GLN attenuates myocardial injury in cardiac surgery patients.
  
  
  METHODS
  Patients undergoing elective cardiac surgery, requiring cardiopulmonary bypass, were enrolled in a randomized, double-blind pilot trial to receive 25 g twice of oral alanyl-glutamine (GLN; n = 7) or maltodextrin (CONT; n = 7) daily for 3 days preoperatively. Serum troponin (TROP I), creatine kinase (CK-MB), and myoglobin (MG) were measured at multiple perioperative time points. Clinical outcomes were also recorded and assessed.
  
  
  RESULTS
  GLN therapy significantly decreased TROP I levels at 24, 48, and 72 hours postoperatively (all P < .05) vs CONT. GLN also reduced CK-MB at 24 and 48 hours (P < .05, P < .001) vs CONT. MG was reduced at 24 hours vs control (P = .0397). GLN also significantly reduced pooled clinical complications vs CONT (P = .03).
  
  
  CONCLUSIONS
  This pilot study showed that pharmacologically dosed oral GLN therapy prior to cardiac surgery was safe, well tolerated, and feasible. GLN therapy reduced myocardial injury and clinical complications in this small randomized, blinded feasibility trial. These data indicate that a larger trial of preoperative GLN therapy in patients undergoing cardiac surgery is needed to confirm clinical benefit.
authors.affiliation: University of Colorado School of Medicine, Aurora, Colorado, USA.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Sufit
authors.forename: Lindsay B
authors.initials: LB
authors.lastname: Weitzel
authors.forename: Christine
authors.initials: C
authors.lastname: Hamiel
authors.forename: Kelly
authors.initials: K
authors.lastname: Queensland
authors.forename: Ira
authors.initials: I
authors.lastname: Dauber
authors.forename: Olav
authors.initials: O
authors.lastname: Rooyackers
authors.forename: Paul E
authors.initials: PE
authors.lastname: Wischmeyer
mesh_terms: D000284:Administration, Oral; D000368:Aged; D006348:Cardiac Surgical Procedures / Q000009:adverse effects; D002315:Cardiopulmonary Bypass / Q000379:methods; D003402:Creatine Kinase / Q000097:blood; D004151:Dipeptides / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005240:Feasibility Studies; D005260:Female; D005973:Glutamine / Q000008:administration & dosage* / Q000097:blood; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D009211:Myoglobin / Q000097:blood; D010865:Pilot Projects; D011134:Polysaccharides / Q000008:administration & dosage; D016896:Treatment Outcome; D014336:Troponin / Q000097:blood
chemical_list: D004151:Dipeptides; D018840:HSP70 Heat-Shock Proteins; D009211:Myoglobin; D011134:Polysaccharides; D014336:Troponin; D005973:Glutamine; C008315:maltodextrin; D003402:Creatine Kinase; C054122:alanylglutamine