title: Oral Coenzyme Q10 supplementation does not prevent cardiac alterations during a high altitude trek to everest base cAMP.
abstract: Exposure to high altitude is associated with sustained, but reversible, changes in cardiac mass, diastolic function, and high-energy phosphate metabolism. Whilst the underlying mechanisms remain elusive, tissue hypoxia increases generation of reactive oxygen species (ROS), which can stabilize hypoxia-inducible factor (HIF) transcription factors, bringing about transcriptional changes that suppress oxidative phosphorylation and activate autophagy. We therefore investigated whether oral supplementation with an antioxidant, Coenzyme Q10, prevented the cardiac perturbations associated with altitude exposure. Twenty-three volunteers (10 male, 13 female, 46±3 years) were recruited from the 2009 Caudwell Xtreme Everest Research Treks and studied before, and within 48 h of return from, a 17-day trek to Everest Base Camp, with subjects receiving either no intervention (controls) or 300 mg Coenzyme Q10 per day throughout altitude exposure. Cardiac magnetic resonance imaging and echocardiography were used to assess cardiac morphology and function. Following altitude exposure, body mass fell by 3 kg in all subjects (p<0.001), associated with a loss of body fat and a fall in BMI. Post-trek, left ventricular mass had decreased by 11% in controls (p<0.05) and by 16% in Coenzyme Q10-treated subjects (p<0.001), whereas mitral inflow E/A had decreased by 18% in controls (p<0.05) and by 21% in Coenzyme Q10-treated subjects (p<0.05). Coenzyme Q10 supplementation did not, therefore, prevent the loss of left ventricular mass or change in diastolic function that occurred following a trek to Everest Base Camp.
authors.affiliation: 1 Department of Physiology, Anatomy and Genetics, University of Oxford , United Kingdom .
authors.forename: Cameron J
authors.initials: CJ
authors.lastname: Holloway
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Murray
authors.forename: Kay
authors.initials: K
authors.lastname: Mitchell
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Martin
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Johnson
authors.forename: Lowri E
authors.initials: LE
authors.lastname: Cochlin
authors.forename: Ion
authors.initials: I
authors.lastname: Codreanu
authors.forename: Sundeep
authors.initials: S
authors.lastname: Dhillon
authors.forename: George W
authors.initials: GW
authors.lastname: Rodway
authors.forename: Tom
authors.initials: T
authors.lastname: Ashmore
authors.forename: Denny Z H
authors.initials: DZ
authors.lastname: Levett
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
authors.forename: Hugh E
authors.initials: HE
authors.lastname: Montgomery
authors.forename: Michael P W
authors.initials: MP
authors.lastname: Grocott
authors.forename: Kieran
authors.initials: K
authors.lastname: Clarke
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology; D000284:Administration, Oral; D000328:Adult; D000975:Antioxidants / Q000494:pharmacology; D001794:Blood Pressure / Q000502:physiology; D015992:Body Mass Index; D002306:Cardiac Volume / Q000187:drug effects*; D015687:Cell Hypoxia / Q000502:physiology; D003971:Diastole / Q000187:drug effects; D019587:Dietary Supplements; D004452:Echocardiography; D005260:Female; D006352:Heart Ventricles / Q000187:drug effects; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009051:Mountaineering / Q000502:physiology*; D010710:Phosphates / Q000378:metabolism; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000494:pharmacology; D014815:Vitamins / Q000494:pharmacology*
chemical_list: D000975:Antioxidants; D010710:Phosphates; D014815:Vitamins; D014451:Ubiquinone; C024989:coenzyme Q10
keywords: Coenzyme Q10; altitude; cardiac metabolism; heart function; hypoxia