title: Voluntary wheel running does not affect lipopolysaccharide-induced depressive-like behavior in young adult and aged mice.
abstract: OBJECTIVE
  Peripheral stimulation of the innate immune system with lipopolysaccharide (LPS) causes prolonged depressive-like behavior in aged mice that is dependent on indoleamine 2,3 dioxygenase (IDO) activation. Regular moderate-intensity exercise training has been shown to exert neuroprotective effects that might reduce depressive-like behavior in aged mice. The purpose of this study was to test the hypothesis that voluntary wheel running (VWR) would attenuate LPS-induced depressive-like behavior and brain IDO gene expression in 4- and 22-month-old C57BL/6J mice.
  
  
  METHODS
  Mice were housed with a running wheel (VWR) or no wheel (standard) for 30 (young adult mice) or 70 days (aged mice), after which they were intraperitoneally injected with LPS (young adult mice: 0.83 mg/kg; aged mice: 0.33 mg/kg).
  
  
  RESULTS
  Young adult VWR mice ran on average 6.9 km/day, while aged VWR mice ran on average 3.4 km/day. Both young adult and aged VWR mice increased their forced exercise tolerance compared to their respective standard control groups. VWR had no effect on LPS-induced anorexia, weight loss, increased immobility in the tail suspension test and decreased sucrose preference in either young adult or aged mice. Four (young adult mice) and 24 h (aged mice) after injection of LPS, mRNA transcripts for TNF-α, IL-1β, IL-6, and IDO were upregulated in the whole brain independently of VWR.
  
  
  CONCLUSIONS
  Prolonged physical exercise has no effect on the neuroinflammatory response to LPS and its behavioral consequences in young adult and aged mice.
authors.affiliation: Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign, Urbana, Ill., USA.
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Martin
authors.forename: Robert
authors.initials: R
authors.lastname: Dantzer
authors.forename: Keith W
authors.initials: KW
authors.lastname: Kelley
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Woods
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D003863:Depression / Q000139:chemically induced* / Q000534:rehabilitation*; D004195:Disease Models, Animal; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods*; D005221:Fatigue / Q000139:chemically induced; D005518:Food Preferences / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D019417:Hindlimb Suspension; D008070:Lipopolysaccharides / Q000633:toxicity*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D012420:Running; D018434:Sickness Impact Profile
chemical_list: D016207:Cytokines; D008070:Lipopolysaccharides