title: Increased nerve growth factor serum levels in top athletes.
abstract: OBJECTIVE
  The nerve growth factor (NGF) is the main neurotrophin, which, besides being an important growth factor for nerves, plays an important role as a mediator of inflammation. Nerve growth factor has been shown to increase in relation to stress stimuli and in allergic diseases in humans as well as after physical exercise in animal models. This study aims at evaluating NGF serum levels in top athletes, a population sample in which allergic and neuro-immune diseases are reported with a significantly increased prevalence.
  
  
  METHODS
  Observational, cross-sectional, multicenter study.
  
  
  METHODS
  Institutional, tertiary care.
  
  
  METHODS
  Ninety-six Italian pre-Olympic athletes (44 allergic and 52 nonallergic) and 49 matched controls selected within the Italian National Olympic delegation (n = 435).
  
  
  METHODS
  Nerve growth factor serum levels determined through an enzyme-linked immunosorbent assay.
  
  
  METHODS
  Parametric or nonparametric tests were used for comparing NGF serum levels among different study groups depending on value distributions.
  
  
  RESULTS
  Nerve growth factor serum levels were significantly higher in athletes than in controls independently from the presence of allergy. Nerve growth factor mean values were 368.3 ± 776.3 pg/mL in the sample of athletes and 174.1 ± 483.7 pg/mL in the control group (P < 0.001).
  
  
  CONCLUSIONS
  This is the first study showing that intense and prolonged physical exercise is associated with an increase of NGF serum levels in athletes. Whether the increased NGF production might be linked to the prevalent Th2 response observed in allergic diseases and after physical exercise and whether it might be related to the patophysiology of neuro-immune disorders as such amyotrophic lateral sclerosis, reported with a higher prevalence in athletes, should deserve further investigations.
authors.affiliation: Department of Medicine, Lung Function Unit, Sapienza University of Rome, Rome, Italy. matteo.bonini@uniroma1.it
authors.forename: Matteo
authors.initials: M
authors.lastname: Bonini
authors.forename: Daniela
authors.initials: D
authors.lastname: Fioretti
authors.forename: Vittorio
authors.initials: V
authors.lastname: Sargentini
authors.forename: Stefano
authors.initials: S
authors.lastname: Del Giacco
authors.forename: Monica
authors.initials: M
authors.lastname: Rinaldi
authors.forename: Carlo
authors.initials: C
authors.lastname: Tranquilli
authors.forename: Sergio
authors.initials: S
authors.lastname: Bonini
mesh_terms: D000328:Adult; D056352:Athletes; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000097:blood*; D007558:Italy; D008297:Male; D020932:Nerve Growth Factor / Q000097:blood*; D055815:Young Adult
chemical_list: D020932:Nerve Growth Factor