3.2. Vit D improves Histopathological Scores of Mucositis
Light microscopic examination of the parts of the small intestine in the control mice showed normal morphology with villi, long crypts, intact lining epithelium with normal mucus-secreting cells, and normal cellularity lamina propria (Fig 2A). The administration of IL-22 alone caused a slight alteration in mucosal morphology in the small intestine. The tips of the villi were mildly blunted but the crypts were generally normal. As is seen from Figure 2A, normal mucosa and structures are monitored on the full-thickness histopathological sections of the intestine tissue of the Vit-D-treated mice. Histological studies showed that MTX treatment-induced serious damage to the intestine (Fig 2). The results revealed that MTX‑induced small intestinal injury was characterized by villous shortening, leukocyte infiltration, crypt abscess, and crypt epithelial damage in the mucosa (Fig 2A). Mild villus superficial epithelial damage, leukocyte infiltration, and protected crypt structures are seen in the intestinal tissue of the MTX+IL-22 group. Clear improvement in the intestine was noticed when the mice were treated with MTX and the Vit-D. The histopathological findings of our study revealed that Vit D ameliorated mucosal destruction and preserved the intestinal epithelium morphology, but even mild pathological changes continue such as crypt abscess.