title: Profile of cerebrospinal microRNAs in fibromyalgia.
abstract: BACKGROUND
  Fibromyalgia (FM) is characterized by chronic pain and reduced pain threshold. The pathophysiology involves disturbed neuroendocrine function, including impaired function of the growth hormone/insulin-like growth factor-1 axis. Recently, microRNAs have been shown to be important regulatory factors in a number of diseases. The aim of this study was to try to identify cerebrospinal microRNAs with expression specific for FM and to determine their correlation to pain and fatigue.
  
  
  METHODS
  The genome-wide profile of microRNAs in cerebrospinal fluid was assessed in ten women with FM and eight healthy controls using real-time quantitative PCR. Pain thresholds were examined by algometry. Levels of pain (FIQ pain) were rated on a 0-100 mm scale (fibromyalgia impact questionnaire, FIQ). Levels of fatigue (FIQ fatigue) were rated on a 0-100 mm scale using FIQ and by multidimensional fatigue inventory (MFI-20) general fatigue (MFIGF).
  
  
  RESULTS
  Expression levels of nine microRNAs were significantly lower in patients with FM patients compared to healthy controls. The microRNAs identified were miR-21-5p, miR-145-5p, miR-29a-3p, miR-99b-5p, miR-125b-5p, miR-23a-3p, 23b-3p, miR-195-5p, miR-223-3p. The identified microRNAs with significantly lower expression in FM were assessed with regard to pain and fatigue. miR-145-5p correlated positively with FIQ pain (r=0.709, p=0.022, n=10) and with FIQ fatigue (r=0.687, p=0.028, n=10).
  
  
  CONCLUSIONS
  To our knowledge, this is the first study to show a disease-specific pattern of cerebrospinal microRNAs in FM. We have identified nine microRNAs in cerebrospinal fluid that differed between FM patients and healthy controls. One of the identified microRNAs, miR-145 was associated with the cardinal symptoms of FM, pain and fatigue.
authors.affiliation: Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Göteborg, Sweden.
authors.forename: Jan L
authors.initials: JL
authors.lastname: Bjersing
authors.forename: Christopher
authors.initials: C
authors.lastname: Lundborg
authors.forename: Maria I
authors.initials: MI
authors.lastname: Bokarewa
authors.forename: Kaisa
authors.initials: K
authors.lastname: Mannerkorpi
mesh_terms: D016022:Case-Control Studies; D005221:Fatigue / Q000150:complications; D005260:Female; D005356:Fibromyalgia / Q000134:cerebrospinal fluid* / Q000150:complications / Q000235:genetics*; D055106:Genome-Wide Association Study; D006801:Humans; D035683:MicroRNAs / Q000134:cerebrospinal fluid* / Q000235:genetics; D008875:Middle Aged; D010146:Pain / Q000150:complications; D059467:Transcriptome
chemical_list: D035683:MicroRNAs