title: Forced treadmill exercise training exacerbates inflammation and causes mortality while voluntary wheel training is protective in a mouse model of colitis.
abstract: The purpose of this study was to examine whether exercise training reduced inflammation and symptomology in a mouse model of colitis. We hypothesized that moderate forced treadmill running (FTR) or voluntary wheel running (VWR) would reduce colitis symptoms and colon inflammation in response to dextran sodium sulfate (DSS). Male C57Bl/6J mice were randomized to sedentary, moderate intensity FTR (8-12 m/min, 40 min, 6 weeks, 5x/week), or VWR (30 days access to wheels). DSS was given at 2% (w/v) in drinking water over 5 days. Mice discontinued exercise 24 h prior to and during DSS treatment. Colons were harvested on Days 6, 8 and 12 in FTR and Day 8 post-DSS in VWR experiments. Contrary to our hypothesis, we found that moderate FTR exacerbated colitis symptomology and inflammation as measured by significant (p<0.05) increases in diarrhea and IL-6, IL-1β, IL-17 colon gene expression. We also observed higher mortality (3/10 died vs. 0/10, p=0.07) in the FTR/DSS group. In contrast, VWR alleviated colitis symptoms and reduced inflammatory gene expression in the colons of DSS-treated mice (p<0.05). While DSS treatment reduced food/fluid intake and body weight, there was a tendency for FTR to exacerbate, and for VWR to attenuate, this effect. FTR (in the absence of DSS) increased gene expression of the chemokine and antibacterial protein CCL6 suggesting that FTR altered gut homeostasis that may be related to the exaggerated response to DSS. In conclusion, we found that FTR exacerbated, whereas VWR attenuated, symptoms and inflammation in response to DSS.
authors.affiliation: Departments of Kinesiology and Community Health, University of Illinois, Urbana-Champaign, IL, United States; Integrative Immunology and Behavior Group, University of Illinois, Urbana-Champaign, IL, United States.
authors.forename: Marc D
authors.initials: MD
authors.lastname: Cook
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Martin
authors.forename: Collette
authors.initials: C
authors.lastname: Williams
authors.forename: Keith
authors.initials: K
authors.lastname: Whitlock
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Wallig
authors.forename: Brandt D
authors.initials: BD
authors.lastname: Pence
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Woods
mesh_terms: D000818:Animals; D019742:Chemokines, CC / Q000096:biosynthesis; D003092:Colitis / Q000209:etiology / Q000276:immunology / Q000517:prevention & control*; D003911:Dextrans / Q000008:administration & dosage; D004195:Disease Models, Animal; D007249:Inflammation / Q000209:etiology* / Q000401:mortality / Q000517:prevention & control*; D008297:Male; D051379:Mice; D010805:Physical Conditioning, Animal / Q000009:adverse effects*; D011897:Random Allocation; D012420:Running / Q000523:psychology; D013315:Stress, Psychological / Q000209:etiology / Q000401:mortality / Q000473:pathology*; D013431:Sulfates / Q000008:administration & dosage; D015431:Weight Loss
chemical_list: D019742:Chemokines, CC; D003911:Dextrans; D013431:Sulfates; C012036:sodium sulfate; C070959:Ccl6 protein, mouse
keywords: Colitis; Dextran sodium sulphate; Exercise; Inflammation; Inflammatory bowel disease; Serum amyloid A; Stress; Treadmill running; Voluntary wheel running