The Expression of Msi-1 and Its Significance in Small Intestinal Mucosa Severely Damaged by High-Dose 5-FU

OBJECTIVE: The purpose was to investigate the expression of musashi-1 (msi-1) and its significances in small intestinal mucosa that was severely damaged by high-dose 5-FU. METHODS: A total of 40 adult C57BL/6J mice were divided into two groups: the control group (n = 8, group A) and experimental group (n = 32). The mice in the control group were treated with PBS by intraperitoneal injection, and the other mice were treated with high-dose 5-FU (150 mg/kg body weight for 5 consecutive days) by intraperitoneal injection. At the 1st (group B), 3rd (group C) and 5th (group D) day after treatment with high-dose 5-FU, the dying mice were killed, HE staining and immunohistochemical techniques were used to detect the expression of the putative marker of intestinal epithelial stem cells, msi-1, in samples of the middle intestine from these mice, and the percentage of the msi-1-positive cells from the intestinal mucosal cells of the mice in group B was detected by FACS. RESULTS: After treatment with high-dose 5-FU, the intestinal mucosa suffered severe damage: the villi and crypts disappeared, the number of msi-1-positive cells increased greatly, the intestinal epithelial cells could be divided into two fractions by FACS, and the percentage of msi-1-positive cells was up to 67.75% in the fraction in which the value of FSC was higher. CONCLUSIONS: After treatment with high-dose 5-FU, the percentage of intestinal stem cells had increased significantly, which was useful for the further isolation and enrichment of intestinal epithelial stem cells.