title: Functional coupling of adenine nucleotide translocase and mitochondrial creatine kinase is enhanced after exercise training in lung transplant skeletal muscle.
abstract: Mechanisms responsible for limitation of exercise capacity in lung transplant recipients (LR) and benefits gained by exercise training were studied. Mitochondrial respiration parameters, energy transfer, and cell structure were assessed in vastus lateralis biopsies using the permeabilized fiber technique with histochemical and morphometric measurements. Twelve male controls (C) and 12 LR performed exercise training over 12 wk. Before exercise training, there were strong correlations between exercise capacity (maximal O(2) consumption and endurance time at 70% maximal power output) and cellular events, as assessed by percentage of type I fibers and apparent K(m) for exogenous ADP. Anticalcineurins were not involved in LR exercise limitation, since there were no differences in maximal mitochondrial rate of respiration before exercise training and no abnormalities in respiratory chain complexes compared with C. Training resulted in a significant increase in physiological parameters both at the cellular (apparent K(m) for exogenous ADP and stimulating effect of creatine) and integrated (maximal O(2) consumption, power output at ventilatory threshold, maximal power output, and endurance time at 70% maximal power output) levels in LR and C. After the training period, improvements in maximal O(2) consumption and in maximal mitochondrial rate of respiration were noted, as well as changes in endurance time and percentage of type I fibers. Because there were no changes in diameters and fiber types, baseline alteration of apparent K(m) for exogenous ADP and its improvement after training might be related to changes within the intracellular energetic units. After the training period, intracellular energetic units exhibited a higher control of mitochondrial respiration by creatine linked to a more efficient functional coupling adenine nucleotide translocase-mitochondrial creatine kinase, resulting in better exercise performances in C and LR.
authors: Laboratoire de Bioénergétique Fondamentale et Appliquée, Institut National de la Santé et de la Recherche Médicale E221, Université Joseph Fourier, Grenoble, France.
authors: Karen
authors: K
authors: Guerrero
authors: Bernard
authors: B
authors: Wuyam
authors: Paulette
authors: P
authors: Mezin
authors: Isabelle
authors: I
authors: Vivodtzev
authors: Marko
authors: M
authors: Vendelin
authors: Jean-Christian
authors: JC
authors: Borel
authors: Rachid
authors: R
authors: Hacini
authors: Olivier
authors: O
authors: Chavanon
authors: Sandrine
authors: S
authors: Imbeaud
authors: Valdur
authors: V
authors: Saks
authors: Christophe
authors: C
authors: Pison
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000328:Adult; D000368:Aged; D003402:Creatine Kinase / Q000378:metabolism*; D052281:Creatine Kinase, Mitochondrial Form; D015444:Exercise / Q000502:physiology*; D017079:Exercise Tolerance / Q000502:physiology*; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D016040:Lung Transplantation / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D000226:Mitochondrial ADP, ATP Translocases / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology
chemical_list: D007527:Isoenzymes; D000226:Mitochondrial ADP, ATP Translocases; D003402:Creatine Kinase; D052281:Creatine Kinase, Mitochondrial Form