title: The effects of moderate exercise on chronic stress-induced intestinal barrier dysfunction and antimicrobial defense.
abstract: The purpose of this study was to examine the effect of moderate exercise on repeated restraint stress (RRS)-induced intestinal barrier dysfunction and explore possible mechanisms in a mouse model. Male Balb/c mice (6weeks) were randomized into 7 groups: CON functioned as controls with no intervention; RRS was subjected to 6h per day RRS for 7 consecutive days; RRS+SWIM received 30min per day of swimming prior to RRS; CON+SWIM only received 30min per day of swimming; and the other groups received one session of 30min swimming prior to sacrifice at 1-, 3- and 6h recovery. Intestinal permeability was quantified with FITC-dextran. Bacterial translocation was determined by quantification of bacterial colony forming units (CFUs) in cultured mesenteric lymph nodes (MLN), and with fluorescence in situ hybridization (FISH). Antimicrobial related gene expression at baseline and 1h after one session of 30min swimming was tested by quantitative real-time polymerase chain reaction (Q-PCR) in small intestinal segments. Protein expression of 5 genes with statistically significant increase was measured at baseline, and 1-, 3- and 6h post-swimming using enzyme-linked immunosorbent assay (ELISA). Thirty minutes per day of swimming before RRS attenuated bacterial translocations and maintained intestinal permeability. Gene expression and protein levels for four antimicrobial peptides (α-defensin 5, β-defensin 1, RegIIIβ and RegIIIγ) were significantly increased after one 30min swimming session. In conclusion, moderate exercise attenuated chronic stress-induced intestinal barrier dysfunction in mice, possibly due to augmentation of antimicrobial responses in the small intestine.
authors.affiliation: Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China.
authors.forename: Beibei
authors.initials: B
authors.lastname: Luo
authors.affiliation: Department of Diving Medicine, Naval Medical Research Institute, Shanghai, China; Department of Cell Biology, Second Military Medical University, Shanghai, China.
authors.forename: Dao
authors.initials: D
authors.lastname: Xiang
authors.affiliation: Human Performance Laboratory, Appalachian State University, North Carolina Research Campus, Kannapolis, NC, United States.
authors.forename: David C
authors.initials: DC
authors.lastname: Nieman
authors.affiliation: Key Laboratory of Exercise and Health Sciences of Ministry of Education, Shanghai University of Sport, Shanghai, China. Electronic address: chenpeijie@sus.edu.cn.
authors.forename: Peijie
authors.initials: P
authors.lastname: Chen
mesh_terms: D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics*; D018407:Bacterial Physiological Phenomena; D015870:Gene Expression; D007413:Intestinal Mucosa / Q000378:metabolism*; D007422:Intestines / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010539:Permeability; D010805:Physical Conditioning, Animal / Q000502:physiology*; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000378:metabolism*; D013550:Swimming / Q000502:physiology
chemical_list: D023181:Antimicrobial Cationic Peptides
keywords: Antimicrobial peptides; Chronic stress; Intestinal barrier; Moderate exercise; Mucosal immunity; Small intestine; Swimming