Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jun 14, 2016; 22(22): 5211-5227
Published online Jun 14, 2016. doi: 10.3748/wjg.v22.i22.5211
Visceral hypersensitive rats share common dysbiosis features with irritable bowel syndrome patients
Xiao-Yan Zhou, Ming Li, Xia Li, Xin Long, Xiu-Li Zuo, Xiao-Hua Hou, Ying-Zi Cong, Yan-Qing Li
Xiao-Yan Zhou, Ming Li, Xia Li, Xin Long, Xiu-Li Zuo, Yan-Qing Li, Department of Gastroenterology, Shandong University, Qilu Hospital, Jinan 250012, Shandong Province, China
Xiao-Hua Hou, Department of Gastroenterology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430074, Hubei Province, China
Ying-Zi Cong, Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX 77555-1070, United States
Author contributions: Zhou XY, Li M and Li YQ designed the research; Zuo Xl and Li X performed the research; Li M analyzed the data; Li M and Zhou XY wrote the paper; Zhou XY, Hou XH, Cong YZ and Li YQ made critical revisions to this manuscript; Zhou XY and Li M contributed equally to this work.
Supported by National Natural Science Foundation of China, No. 81330012 and No. 81170352.
Institutional animal care and use committee statement: All experiments were reviewed and approved by the Ethical Committee and Institutional Animal Care and Use Committee of Qilu Hospital (KYLL-2013-005), and the methods were performed in strict accordance with the Animal Management Rules of the Chinese Ministry of Health.
Conflict-of-interest statement: The authors declare no conflict of interest.
Data sharing statement: Data will be available for scientific sharing. The sra number for the sequencing data is pending.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Yan-Qing Li, MD, Department of Gastroenterology, Shandong University, Qilu Hospital, 107 Wenhuaxi Road, Jinan 250012, Shandong Province, China. liyanqing@sdu.edu.cn
Telephone: +86-531-82166090 Fax: +86-531-82166090
Received: December 21, 2015
Peer-review started: December 22, 2015
First decision: January 13, 2016
Revised: March 1, 2016
Accepted: March 18, 2016
Article in press: March 1, 2016
Published online: June 14, 2016
Processing time: 163 Days and 21.7 Hours
Abstract

AIM: To evaluate gut microbial dysbiosis in two visceral hypersensitive models in comparison with irritable bowel syndrome (IBS) patients and to explore the extent to which these models capture the dysbiosis of IBS patients.

METHODS: Visceral hypersensitivity was developed using the maternal separation (MS) rat model and post-inflammatory rat model. The visceral sensitivity of the model groups and control group was evaluated using the abdominal withdraw reflex score and electromyography in response to graded colorectal distention. The 16S ribosomal RNA gene from fecal samples was pyrosequenced and analyzed. The correlation between dysbiosis in the microbiota and visceral hypersensitivity was calculated. Positive findings were compared to sequencing data from a published human IBS cohort.

RESULTS: Dysbiosis triggered by neonatal maternal separation was lasting but not static. Both MS and post-inflammatory rat fecal microbiota deviated from that of the control rats to an extent that was larger than the co-housing effect. Two short chain fatty acid producing genera, Fusobacterium and Clostridium XI, were shared by the human IBS cohort and by the maternal separation rats and post-inflammatory rats, respectively, to different extents. Fusobacterium was significantly increased in the MS group, and its abundance positively correlated with the degree of visceral hypersensitivity. Porphyromonadaceae was a protective biomarker for both the rat control group and healthy human controls.

CONCLUSION: The dysbiosis MS rat model and the post-inflammatory rat model captured some of the dysbiosis features of IBS patients. Fusobacterium, Clostridium XI and Porphyromonadaceae were identified as targets for future mechanistic research.

Keywords: Animal model, Irritable bowel syndrome, Microbiota, Pyrosequencing, 16S rRNA gene

Core tip: Dysbiosis of the gastrointestinal microbiota and hypersensitivity to colonic distension are critical features of irritable bowel syndrome (IBS). For animal models, the correlation between dysbiosis in the microbiota and visceral hypersensitivity remains unknown. This study identified common biomarkers between the animal models and IBS patients, which may be targets for future mechanistic research.