title: MicroRNAs as Biomarkers for Acute Atrial Remodeling in Marathon Runners (The miRathon Study--A Sub-Study of the Munich Marathon Study).
abstract: BACKGROUND
  Physical activity is beneficial for individual health, but endurance sport is associated with the development of arrhythmias like atrial fibrillation. The underlying mechanisms leading to this increased risk are still not fully understood. MicroRNAs are important mediators of proarrhythmogenic remodeling and have potential value as biomarkers in cardiovascular diseases. Therefore, the objective of our study was to determine the value of circulating microRNAs as potential biomarkers for atrial remodeling in marathon runners (miRathon study).
  
  
  METHODS
  30 marathon runners were recruited into our study and were divided into two age-matched groups depending on the training status: elite (ER, ≥55 km/week, n = 15) and non-elite runners (NER, ≤40 km/week, n = 15). All runners participated in a 10 week training program before the marathon. MiRNA plasma levels were measured at 4 time points: at baseline (V1), after a 10 week training period (V2), immediately after the marathon (V3) and 24h later (V4). Additionally, we obtained clinical data including serum chemistry and echocardiography at each time point.
  
  
  RESULTS
  MiRNA plasma levels were similar in both groups over time with more pronounced changes in ER. After the marathon miR-30a plasma levels increased significantly in both groups. MiR-1 and miR-133a plasma levels also increased but showed significant changes in ER only. 24h after the marathon plasma levels returned to baseline. MiR-26a decreased significantly after the marathon in elite runners only and miR-29b showed a non-significant decrease over time in both groups. In ER miRNA plasma levels showed a significant correlation with LA diameter, in NER miRNA plasma levels did not correlate with echocardiographic parameters.
  
  
  CONCLUSIONS
  MiRNAs were differentially expressed in the plasma of marathon runners with more pronounced changes in ER. Plasma levels in ER correlate with left atrial diameter suggesting that circulating miRNAs could potentially serve as biomarkers of atrial remodeling in athletes.
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.|DZHK (German Centre for Cardiovascular Research), Partner site Munich, Munich Heart Alliance, Munich, Germany.|Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, MA, United States of America.
authors: Sebastian
authors: S
authors: Clauss
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.|DZHK (German Centre for Cardiovascular Research), Partner site Munich, Munich Heart Alliance, Munich, Germany.
authors: Reza
authors: R
authors: Wakili
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.
authors: Bianca
authors: B
authors: Hildebrand
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.|DZHK (German Centre for Cardiovascular Research), Partner site Munich, Munich Heart Alliance, Munich, Germany.
authors: Stefan
authors: S
authors: Kääb
authors: Institute for Medical Informatics Biometry and Epidemiology, Ludwig-Maximilians-UniversitätMünchen, Munich, Germany.
authors: Eva
authors: E
authors: Hoster
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.
authors: Ina
authors: I
authors: Klier
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.
authors: Eimo
authors: E
authors: Martens
authors: Cardiovascular Research Center, Massachusetts General Hospital, Charlestown, MA, United States of America.
authors: Alan
authors: A
authors: Hanley
authors: Department of Prevention and Sports Medicine, TechnischeUniversitätMünchen, Klinikumrechts der Isar (MRI), Munich, Germany.|Sports Medicine, Institute of Exercise and Health Sciences, University Basel, Basel, Switzerland.
authors: Henner
authors: H
authors: Hanssen
authors: DZHK (German Centre for Cardiovascular Research), Partner site Munich, Munich Heart Alliance, Munich, Germany.|Department of Prevention and Sports Medicine, TechnischeUniversitätMünchen, Klinikumrechts der Isar (MRI), Munich, Germany.
authors: Martin
authors: M
authors: Halle
authors: Medizinische Klinik und Poliklinik 1, Campus Grosshadern, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.
authors: Thomas
authors: T
authors: Nickel
mesh_terms: D000328:Adult; D001281:Atrial Fibrillation / Q000097:blood / Q000209:etiology / Q000235:genetics; D064752:Atrial Remodeling / Q000235:genetics* / Q000502:physiology*; D015415:Biomarkers / Q000097:blood; D052279:Creatine Kinase, MB Form / Q000097:blood; D004452:Echocardiography; D005819:Genetic Markers; D005858:Germany; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006461:Hemolysis; D006801:Humans; D008297:Male; D035683:MicroRNAs / Q000097:blood* / Q000235:genetics*; D008875:Middle Aged; D010807:Physical Endurance / Q000235:genetics / Q000502:physiology; D012420:Running / Q000502:physiology*; D013997:Time Factors; D020107:Troponin T / Q000097:blood
chemical_list: D015415:Biomarkers; D005819:Genetic Markers; D035683:MicroRNAs; D020107:Troponin T; D052279:Creatine Kinase, MB Form