title: Potential neurobiological benefits of exercise in chronic pain and posttraumatic stress disorder: Pilot study.
abstract: This pilot study assessed the effects of cardiopulmonary exercise testing and cardiorespiratory fitness on plasma neuropeptide Y (NPY), allopregnanolone and pregnanolone (ALLO), cortisol, and dehydroepiandrosterone (DHEA), and their association with pain sensitivity. Medication-free trauma-exposed participants were either healthy (n = 7) or experiencing comorbid chronic pain/posttraumatic stress disorder (PTSD) (n = 5). Peak oxygen consumption (VO2) during exercise testing was used to characterize cardiorespiratory fitness. Peak VO2 correlated with baseline and peak NPY levels (r = 0.66, p < 0.05 and r = 0.69, p < 0.05, respectively), as well as exercise-induced changes in ALLO (r = 0.89, p < 0.001) and peak ALLO levels (r = 0.71, p < 0.01). NPY levels at the peak of exercise correlated with pain threshold 30 min after exercise (r = 0.65, p < 0.05), while exercise-induced increases in ALLO correlated with pain tolerance 30 min after exercise (r = 0.64, p < 0.05). In contrast, exercise-induced changes in cortisol and DHEA levels were inversely correlated with pain tolerance after exercise (r = -0.69, p < 0.05 and r = -0.58, p < 0.05, respectively). These data suggest that cardiorespiratory fitness is associated with higher plasma NPY levels and increased ALLO responses to exercise, which in turn relate to pain sensitivity. Future work will examine whether progressive exercise training increases cardiorespiratory fitness in association with increases in NPY and ALLO and reductions in pain sensitivity in chronic pain patients with PTSD.
authors.forename: Erica
authors.initials: E
authors.lastname: Scioli-Salter
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Forman
authors.forename: John D
authors.initials: JD
authors.lastname: Otis
authors.forename: Carlos
authors.initials: C
authors.lastname: Tun
authors.forename: Kelly
authors.initials: K
authors.lastname: Allsup
authors.forename: Christine E
authors.initials: CE
authors.lastname: Marx
authors.forename: Richard L
authors.initials: RL
authors.lastname: Hauger
authors.forename: Jillian C
authors.initials: JC
authors.lastname: Shipherd
authors.forename: Diana
authors.initials: D
authors.lastname: Higgins
authors.forename: Anna
authors.initials: A
authors.lastname: Tyzik
authors.forename: Ann M
authors.initials: AM
authors.lastname: Rasmusson
mesh_terms: D000328:Adult; D059350:Chronic Pain / Q000503:physiopathology / Q000534:rehabilitation*; D004185:Disability Evaluation; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D017288:Pain Threshold; D010865:Pilot Projects; D013313:Stress Disorders, Post-Traumatic / Q000503:physiopathology / Q000534:rehabilitation*
keywords: ALLO; NPY; PTSD; VO2; biomarkers; cardiorespiratory fitness; chronic pain; exercise; neurosteroids; pain sensitivity