title: Coenzyme Q10 therapy before cardiac surgery improves mitochondrial function and in vitro contractility of myocardial tissue.
abstract: OBJECTIVE
  Previous clinical trials suggest that coenzyme Q(10) might afford myocardial protection during cardiac surgery. We sought to measure the effect of coenzyme Q(10) therapy on coenzyme Q(10) levels in serum, atrial trabeculae, and mitochondria; to assess the effect of coenzyme Q(10) on mitochondrial function; to test the effect of coenzyme Q(10) in protecting cardiac myocardium against a standard hypoxia-reoxygentation stress in vitro; and to determine whether coenzyme Q(10) therapy improves recovery of the heart after cardiac surgery.
  
  
  METHODS
  Patients undergoing elective cardiac surgery were randomized to receive oral coenzyme Q(10) (300 mg/d) or placebo for 2 weeks preoperatively. Pectinate trabeculae from right atrial appendages were excised, and mitochondria were isolated and studied. Trabeculae were subjected to 30 minutes of hypoxia, and contractile recovery was measured. Postoperative cardiac function and troponin I release were assessed.
  
  
  RESULTS
  Patients receiving coenzyme Q(10) (n = 62) had increased coenzyme Q(10) levels in serum (P = .001), atrial trabeculae (P = .0001), and isolated mitochondria (P = .0002) compared with levels seen in patients receiving placebo (n = 59). Mitochondrial respiration (adenosine diphosphate/oxygen ratio) was more efficient (P = .012), and mitochondrial malondialdehyde content was lower (P = .002) with coenzyme Q(10) than with placebo. After 30 minutes of hypoxia in vitro, pectinate trabeculae isolated from patients receiving coenzyme Q(10) exhibited a greater recovery of developed force compared with those in patients receiving placebo (46.3% +/- 4.3% vs 64.0% +/- 2.9%, P = .001). There was no between-treatment difference in preoperative or postoperative hemodynamics or in release of troponin I.
  
  
  CONCLUSIONS
  Preoperative oral coenzyme Q(10) therapy in patients undergoing cardiac surgery increases myocardial and cardiac mitochondrial coenzyme Q(10) levels, improves mitochondrial efficiency, and increases myocardial tolerance to in vitro hypoxia-reoxygenation stress.
authors.affiliation: The Cardiac Surgical Research Unit, Department of Cardiothoracic Surgery, Alfred Hospital, Baker Heart Research Institute, Melbourne, Australia.
authors.forename: Franklin
authors.initials: F
authors.lastname: Rosenfeldt
authors.forename: Silvana
authors.initials: S
authors.lastname: Marasco
authors.forename: William
authors.initials: W
authors.lastname: Lyon
authors.forename: Michelle
authors.initials: M
authors.lastname: Wowk
authors.forename: Freya
authors.initials: F
authors.lastname: Sheeran
authors.forename: Michael
authors.initials: M
authors.lastname: Bailey
authors.forename: Donald
authors.initials: D
authors.lastname: Esmore
authors.forename: Bruce
authors.initials: B
authors.lastname: Davis
authors.forename: Adrian
authors.initials: A
authors.lastname: Pick
authors.forename: Mark
authors.initials: M
authors.lastname: Rabinov
authors.forename: Julian
authors.initials: J
authors.lastname: Smith
authors.forename: Phillip
authors.initials: P
authors.lastname: Nagley
authors.forename: Salvatore
authors.initials: S
authors.lastname: Pepe
mesh_terms: D000284:Administration, Oral; D000368:Aged; D000704:Analysis of Variance; D015415:Biomarkers / Q000032:analysis; D003067:Coenzymes; D001026:Coronary Artery Bypass / Q000379:methods; D003327:Coronary Disease / Q000473:pathology / Q000601:surgery*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D017558:Elective Surgical Procedures; D005260:Female; D006334:Heart Function Tests; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D008929:Mitochondria, Heart / Q000187:drug effects*; D009200:Myocardial Contraction / Q000187:drug effects*; D011300:Preoperative Care / Q000379:methods*; D011336:Probability; D012016:Reference Values; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D019210:Troponin I / Q000032:analysis*; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000627:therapeutic use*
chemical_list: D015415:Biomarkers; D003067:Coenzymes; D019210:Troponin I; D014451:Ubiquinone; C024989:coenzyme Q10