title: Simulated microgravity disrupts intestinal homeostasis and increases colitis susceptibility.
abstract: The immune systems can be altered by spaceflight in many aspects, but microgravity-related mucosal immune changes and its clinical significance have not been well studied. The purpose of this study was to investigate whether simulated microgravity influences the intestinal homeostasis and increases the susceptibility to colon inflammation. The hindlimb unloading (HU) mouse model was used to simulate the microgravity condition. Three percent dextran sulfate sodium (DSS) was given to mice to induce colitis. Compared to ground control (Ctrl) mice, the HU ones revealed an impaired intestinal homeostasis and increased susceptibility to DSS-induced colitis. This includes an early-onset, 4-fold expansion of segmented filamentous bacteria (SFB), more than 2-fold decrease in regulatory T (Treg) cell numbers and IL-10 production, ∼2-fold increase in colonic IL-1β expression, 2-fold increase in circulating neutrophils, and colonic neutrophil infiltration. The application of antibiotics ameliorated the Treg and IL-10 reductions but did not significantly dampen neutrophilia and elevated expression of colonic IL-1β. These results indicate that the intestinal microflora and innate immune system both respond to simulated microgravity and together, contribute to the proinflammatory shift in the gut microenvironment. The data also emphasize the necessity for evaluating the susceptibility to inflammatory bowel diseases (IBDs) in distant space travels.
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Pingping
authors: P
authors: Li
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Junxiu
authors: J
authors: Shi
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Peng
authors: P
authors: Zhang
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Ke
authors: K
authors: Wang
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Jinglong
authors: J
authors: Li
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Hongju
authors: H
authors: Liu
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Yu
authors: Y
authors: Zhou
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Xi
authors: X
authors: Xu
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Jie
authors: J
authors: Hao
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Xiuyuan
authors: X
authors: Sun
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Xuewen
authors: X
authors: Pang
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Yan
authors: Y
authors: Li
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China.
authors: Hounan
authors: H
authors: Wu
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China qingge@bjmu.edu.cn xpchen2009@163.com.
authors: Xiaoping
authors: X
authors: Chen
authors: *Key Laboratory of Medical Immunology, Ministry of Health, Department of Immunology, School of Basic Medical Sciences, and Peking University Medical and Health Analytical Center, Peking University Health Sciences Center, Beijing, China; State Key Laboratory of Space Medicine Fundamentals and Application, Chinese Astronaut Research and Training Center, Beijing, China; and College of Life Sciences and Key Laboratory of Modern Teaching Technology, Shaanxi Normal University, Xian, China qingge@bjmu.edu.cn xpchen2009@163.com.
authors: Qing
authors: Q
authors: Ge
mesh_terms: D000818:Animals; D003092:Colitis / Q000209:etiology* / Q000378:metabolism; D004195:Disease Models, Animal; D004198:Disease Susceptibility / Q000209:etiology* / Q000378:metabolism; D005260:Female; D006706:Homeostasis / Q000502:physiology*; D007249:Inflammation / Q000209:etiology / Q000378:metabolism; D016753:Interleukin-10 / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000502:physiology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000378:metabolism; D018474:Weightlessness Simulation / Q000379:methods
chemical_list: D053583:Interleukin-1beta; D016753:Interleukin-10
keywords: IL-10; microbiota; neutrophil