title: Endurance Exercise Improves Molecular Pathways of Aerobic Metabolism in Patients With Myositis.
abstract: Endurance exercise demonstrates beneficial effects in polymyositis/dermatomyositis (PM/DM); however, the molecular effects of exercise on skeletal muscle are incompletely understood. We undertook this controlled pilot study to investigate the effects of a 12-week endurance exercise training program on the molecular profile of skeletal muscle in patients with established PM/DM compared to a nonexercised control group of patients with established PM/DM.
  
  
  
  Fifteen patients (7 in the exercise group and 8 in the control group) with paired baseline and 12-week follow-up muscle biopsy samples were included. Messenger RNA expression profiling, mass spectrometry-based quantitative proteomics, and immunohistochemical analyses were performed on muscle biopsy samples to determine molecular adaptations associated with changes in clinical measurements induced by endurance exercise.
  
  
  
  Compared to the control group, the exercise group improved in minutes of cycling time (P < 0.01) and Vo2 max (P < 0.05). The exercise group also had reduced disease activity (P < 0.05) and reduced lactate levels at exhaustion (P < 0.05). Genes related to capillary growth, mitochondrial biogenesis, protein synthesis, cytoskeletal remodeling, and muscle hypertrophy were up-regulated in the exercise group, while genes related to inflammation/immune response and endoplasmic reticulum stress were down-regulated. Mitochondrial pathways including the oxidative phosphorylation metabolic pathway were most affected by the endurance exercise, as demonstrated by proteomics analysis. The exercise group also showed a higher number of capillaries per mm(2) in follow-up biopsy samples (P < 0.05).
  
  
  
  Our data indicate that endurance exercise in patients with established PM and DM may activate an aerobic phenotype and promote muscle growth and simultaneously suppress the inflammatory response in these patients' muscles, as supported by a combination of data on gene expression, proteomics, and capillary density in repeated muscle biopsies.
authors: Vanderbilt University, Nashville, Tennessee, and Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Li Alemo
authors: LA
authors: Munters
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Ingela
authors: I
authors: Loell
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Elena
authors: E
authors: Ossipova
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Joan
authors: J
authors: Raouf
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Maryam
authors: M
authors: Dastmalchi
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Eva
authors: E
authors: Lindroos
authors: George Washington University and Children's National Medical Center, Washington, DC.
authors: Yi-Wen
authors: YW
authors: Chen
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Mona
authors: M
authors: Esbjörnsson
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Marina
authors: M
authors: Korotkova
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Helene
authors: H
authors: Alexanderson
authors: George Washington University and Children's National Medical Center, Washington, DC.
authors: Kanneboyina
authors: K
authors: Nagaraju
authors: Vanderbilt University, Nashville, Tennessee.
authors: Leslie J
authors: LJ
authors: Crofford
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Per-Johan
authors: PJ
authors: Jakobsson
authors: Karolinska Institutet and Karolinska University Hospital, Solna, Stockholm, Sweden.
authors: Ingrid E
authors: IE
authors: Lundberg
mesh_terms: D003882:Dermatomyositis / Q000378:metabolism* / Q000503:physiopathology / Q000628:therapy*; D005081:Exercise Therapy; D006801:Humans; D053858:Metabolic Networks and Pathways; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000503:physiopathology*; D010807:Physical Endurance; D010865:Pilot Projects