Histological and ultrastructural changes of the colon in dextran sodium sulfate‑induced mouse colitis

Abstract

Ulcerative colitis (UC) is a complex disease that results from a dysregulated immune response in the gastrointestinal tract. A mouse model orally administered with dextran sodium sulfate (DSS) is the most widely used experimental animal model of UC. However, the ultrastructure of the colon in mouse colitis is poorly understood. In the present study, colonic specimens from DSS-induced UC mice underwent hematoxylin and eosin staining, Masson's trichrome staining and Verhoeff's elastic staining. In addition, the ultrastructure of samples was examined by transmission electron microscopy. UC was successfully induced by 7 consecutive days of DSS oral administration. The goblet cell architecture of the UC tissue was damaged in the mucosa. Additionally, a significant number of inflammatory cells infiltrated into the stroma and the structure of the intestinal gland was destroyed. The tissue in the submucosa showed significant edema. Hyperplasia was also identified in the submucosa, promoting a disorganized microstructure within the colon wall. Numerous collagen fibers in the muscular layer were disrupted, and the fiber bundles were thinner compared with those in the normal control group. Furthermore, in the DSS-induced UC group, the smooth muscle cell showed edema, the cell membrane structure was unclear and the shape of the nucleus was irregular. In conclusion, the present study revealed important histological and ultrastructural changes in the colon of DSS-induced UC mice. These features may contribute to improved understanding of the pathogenesis and mechanism of UC.

Identification of the Molecular Basis of Nanocurcumin-Induced Telocyte Preservation within the Colon of Ulcerative Colitis Rat Model

“…Analysis of the submucosa revealed significant edema and inflammatory cell infiltration. Our results were in line with previous work [ 24 , 25 ].…”

Fermented Maillard Reaction Products by Lactobacillus gasseri 4M13 Alters the Intestinal Microbiota and Improves Dysfunction in Type 2 Diabetic Mice with Colitis

“…Through the evaluation of colonic histomorphometry and antioxidant enzyme activity, we observed that treatment with FMRP improved IBD in the present study. In part, inflammatory cell infiltration has led to submucosal edema and collagen fiber disruption [ 45 ]. Oxidative stress contributes to the initial stage of the progression of colorectal diseases, and antioxidant enzymes such as CAT, SOD, and Gpx play important roles in IBD.…”

Single Donor FMT Reverses Microbial/Immune Dysbiosis and Induces Clinical Remission in a Rat Model of Acute Colitis

“…Histological/ultrastructural changes of the colon in DSS-induced colitis is represented mainly by the presence of damaged goblet cell architecture in the mucosa, a significant infiltration of inflammatory cells into the stroma as well as destruction of the intestinal gland structure. Moreover, the tissue in the submucosa very often shows significant signs of oedema and hyperplasia [ 65 ]. In terms of immune cells, the infiltration of neutrophils and macrophages is observed as early as on the first day after chemical stimulation, and it is increased over time [ 66 ].…”

“…In our study, mucosal changes of the large intestine involving the rectum were localised especially in the distal colon with decreasing severity towards the proximal part. Histological examination of colonic sections revealed an altered architecture of colon mucosa with typical inflammatory changes in DSS group [ 65 ] whereas faecal transplant had protective effects and was able to restore histopathological changes in the colon possibly due to rebalanced intestinal microbiota. Similar results were obtained in human studies where FMT improved the scores for diarrhoea and mucous membrane lesions in patients with UC [ 67 , 68 ].…”