title: Exercise capacity and immune function in male and female patients with chronic fatigue syndrome (CFS).
abstract: Hyperactivition of an unwanted cellular cascade by the immune-related protein RNase L has been linked to reduced exercise capacity in persons with chronic fatigue syndrome (CFS). This investigation compares exercise capacities of CFS patients with deregulation of the RNase L pathway and CFS patients with normal regulation, while controlling for potentially confounding gender effects. Thirty-five male and seventy-one female CFS patients performed graded exercise tests to voluntary exhaustion. Measures of peak VO2, peak heart rate, body mass index, perceived exertion, and respiratory quotient were entered into a two-way factorial analysis with gender and immune status as independent variables. A significant multivariate main effect was found for immune status (p < 0.01), with no gender effect or interaction. Follow-up analyses identified VO2(peak) as contributing most to the difference. These results implicate abnormal immune activity in the pathology of exercise intolerance in CFS and are consistent with a channelopathy involving oxidative stress and nitric oxide-related toxicity.
authors.affiliation: University of the Pacific, Department of Sport Sciences, Stockton, CA 95211-0197, USA. snells@juno.com
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Snell
authors.forename: J Mark
authors.initials: JM
authors.lastname: Vanness
authors.forename: David R
authors.initials: DR
authors.lastname: Strayer
authors.forename: Staci R
authors.initials: SR
authors.lastname: Stevens
mesh_terms: D000328:Adult; D015992:Body Mass Index; D004722:Endoribonucleases / Q000097:blood; D015444:Exercise; D015673:Fatigue Syndrome, Chronic / Q000276:immunology* / Q000503:physiopathology*; D005260:Female; D006339:Heart Rate; D006801:Humans; D007109:Immunity; D008297:Male; D010101:Oxygen Consumption; D012737:Sex Factors
chemical_list: D004722:Endoribonucleases; C031956:2-5A-dependent ribonuclease