Prevention of Chronic Experimental Colitis Induced by Dextran Sulphate Sodium (DSS) in Mice Treated with FR91
Figure 2
Histological sections of three different portions of the experimental mice colon to show histopathological lesions identified by hematoxylin and eosin staining. (a–c) Transverse sections at three different colorectal levels (proximal, middle, and distal) of mice group 1 treated with FR91 (10%). Note the absence of colonic lesions and the similar epithelial structures observed in normal control mice. (d–f) Transverse sections at three different colorectal levels of mice group 2 treated with DSS (2%) for 5 weeks. In each studied level, multiple histopathological lesions were observed, being particularly clear the severe-grade dysplasia (arrowheads in (d) and (e)) developed in the colon of mice from this group, together with aberrant crypts (arrow in (d)), adenomatous polyps (arrowhead in (f)), and incipient ulcerations (arrow in (f)). (g–I) Transverse sections at three different colorectal levels of mice group 3, with the administration of DSS (2%) for 5 weeks and treated with FR-91 (5%). Although these three colonic levels show a low-grade dysplasia and some scattered mucosal ulcerations, the structural histological pattern in general is functional. (j–l) Transverse sections at three different colorectal levels of mice group 4, with the administration of DSS (2%) for 5 weeks and treated with FR-91 (10%). This group showed a better colorectal histological organization than that observed in group 3 although there are some mild-grade dysplastic crypts mainly at the distal segments. (m–o) Transverse sections at three different colorectal levels of mice group 5, with the administration of DSS (2%) for 5 weeks and treated with FR-91 (20%). These sections show a normal epithelial organization, with well-differentiated cryptal cells and no atypical lesion features. Scale bar: 100 μm.
