COULD THE INTESTINAL EPITHELIAL ALTERATIONS PROMOTED BY ROUX-EN-Y GASTRIC BYPASS EXPLAIN HIGHER TENDENCY FOR COLONIC DISEASES IN BARIATRIC PATIENTS?

Ki-67 in ascending colon: A) experiment and B) control

ABSTRACT

Background:  Intestinal diversions have revolutionized the treatment of morbid obesity due to its viability and sustained response. However, experimental studies suggest, after these derivations, a higher risk of colon cancer.

Aim:  To analyze the histological and immunohistological changes that the jejunojejunal shunt can produce in the jejunum, ileum and ascending colon.

Method:  Twenty-four male Wistar rats were randomly divided into two groups, control (n=12) and experiment (n=12) and subdivided into groups of four. Nine weeks after the jejunojejunal shunt, segmental resection of the excluded jejunum, terminal ileum and ascending colon was performed. Histological analysis focused on the thickness of the mucosa, height of the villi, depth of the crypts and immunohistochemistry in the expression of Ki-67 and p53.

Results:  Significant differences were found between the experiment and control groups in relation to the thickness of the mucosa in the jejunum (p=0.011), in the ileum (p<0.001) and in the colon (p=0.027). There was also a significant difference in relation to the height of the villus in the ileum (p<0.001) and the depth of the crypts in the jejunum (p0.001). The results indicated that there is a significant difference between the groups regarding the expression of Ki-67 in the colon (p<0.001). No significant differences were found between the groups regarding the expression of Ki-67 in the jejunum and ileum. In the P53 evaluation, negative nuclear staining was found in all cases.

Conclusion:  The jejunojejunal deviation performed in the Roux-in-Y gastrojejunal bypass, predispose epithelial proliferative effects, causing an increase in the thickness of the mucosa, height of the villi and depth of the crypts of the jejunum, ileum and ascending colon.

HEADINGS: Jejunoileal bypass; Tumor suppressor protein p53; Ki-67 antigen; Obesity