title: Decreased immunoreactive beta-endorphin in mononuclear leucocytes from patients with chronic fatigue syndrome.
abstract: OBJECTIVE
  To investigate beta-endorphin concentrations in the peripheral blood mononuclear cells (PBMC) of patients with chronic fatigue syndrome (CFS).
  
  
  METHODS
  Sixteen patients with CFS were enrolled in this study. Ten healthy subjects were studied as controls. Beta-endorphin concentrations were measured in PBMC by radioimmunoassay performed with antibodies specific for the C-terminal portion of human beta-endorphin.
  
  
  RESULTS
  Beta-endorphin concentrations in the PBMC of chronic fatigue patients were significantly lower (p < 0.001) than in healthy subjects (mean +/- SD: 8.5 +/- 7.0 vs. 42.6 +/- 22.6).
  
  
  CONCLUSIONS
  Patients with CFS were found to have low levels of PBMC beta-endorphin. This finding may reflect the condition of chronic immune activation in CFS that has been reported in previous investigations. Beta-endorphin concentrations in PBMC seem to mirror the central nervous system homeostasis of the opioid. Therefore, we would postulate that the fatigue and weakness typical of CFS could be related to low beta-endorphin concentrations at the central nervous system level.
authors.affiliation: Istituto di Clinica Medica I, Università degli Studi di Roma La Sapienza, Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Conti
authors.forename: V
authors.initials: V
authors.lastname: Pittoni
authors.forename: P
authors.initials: P
authors.lastname: Sacerdote
authors.forename: R
authors.initials: R
authors.lastname: Priori
authors.forename: P L
authors.initials: PL
authors.lastname: Meroni
authors.forename: G
authors.initials: G
authors.lastname: Valesini
mesh_terms: D000293:Adolescent; D000328:Adult; D015673:Fatigue Syndrome, Chronic / Q000378:metabolism*; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011863:Radioimmunoassay; D001615:beta-Endorphin / Q000276:immunology / Q000378:metabolism*
chemical_list: D001615:beta-Endorphin