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An Unexpected Alteration Colonic Mucus Appearance in the Constipation Model via an Intestinal Microenvironment

Published online by Cambridge University Press:  30 May 2022

Han Gao
Department of Physiology and Pathophysiology, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Chen-chen Gao
Department of Physiology and Pathophysiology, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Tian-tian Wang
Department of Physiology and Pathophysiology, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Lei Gao
Department of Biomedical Informatics, School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
Guang-wen Li
Department of Physiology and Pathophysiology, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Liang-yun Jin
Experimental Center for Morphological Research Platform, Capital Medical University, Beijing 100069, China
Cheng-wei He
Department of Physiology and Pathophysiology, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Bo-ya Wang
Undergraduate Student of 2018 Eight Program of Clinical Medicine, Peking University Health Science Center, Beijing 100069, China
Lucia Zhang
Class of 2025, Loomis Chaffee School, 4 Batchelder Road, Windsor, CT 06095, USA
Yue-xin Guo
Oral Medicine “5+3” process, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Rong-xuan Hua
Department of Clinical Medicine, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
Hong-wei Shang
Experimental Center for Morphological Research Platform, Capital Medical University, Beijing 100069, China
Jing-dong Xu*
Department of Physiology and Pathophysiology, School of Basic Medical Science, Capital Medical University, Beijing 100069, China
*Corresponding author: Jing-dong Xu, E-mail:
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Due to the lack of research between the inner layers in the structure of colonic mucous and the metabolism of fatty acid in the constipation model, we aim to determine the changes in the mucous phenotype of the colonic glycocalyx and the microbial community structure following treatment with Rhubarb extract in our research. The constipation and treatment models are generated using adult male C57BL/6N mice. We perform light microscopy and transmission electron microscopy (TEM) to detect a Muc2-rich inner mucus layer attached to mice colon under different conditions. In addition, 16S rDNA sequencing is performed to examine the intestinal flora. According to TEM images, we demonstrate that Rhubarb can promote mucin secretion and find direct evidence of dendritic structure-linked mucus structures with its assembly into a lamellar network in a pore size distribution in the isolated colon section. Moreover, the diversity of intestinal flora has noticeable changes in constipated mice. The present study characterizes a dendritic structure and persistent cross-links have significant changes accompanied by the alteration of intestinal flora in feces in models of constipation and pretreatment with Rhubarb extract.

Biological Applications
Copyright © The Author(s), 2022. Published by Cambridge University Press on behalf of the Microscopy Society of America

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These authors have contributed equally to this work and share the first authorship.


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