Effect of vitamin A on the CD44 expression in the small intestine of rats with obstructive jaundice

Abstract

Hypothesis: In this study, the influence of obstructive jaundice on the CD44 expression in the rat small intestine and the alterations of this CD44 expression by vitamin A given intraperitoneally (200 IU/g/day) are evaluated.

Materials and methods: In a prospective animal model study, 32 Sprague-Dawley rats were randomized into four groups: group A rats (n = 8) underwent sham operation and were given daily saline intraperitoneally for 2 weeks (sham + saline); group B animals (n = 8) underwent sham operation and were given daily vitamin A intraperitoneally for 2 weeks (sham + vitamin A); group C rats (n = 8) underwent common bile duct ligation and were given daily saline intraperitoneally for 2 weeks (obstructive jaundice + saline), and group D animals (n = 8) underwent common bile duct ligation and were given daily vitamin A intraperitoneally for 2 weeks (obstructive jaundice + vitamin A). After 2 weeks, standardized jejunum and ileum segments were harvested from all animals. The expression of CD44 on the cell surface was evaluated immunohistochemically. Comparisons among the four groups were done.

Results: The plasma bilirubin, aspartate transaminase, alanine transaminase, alkaline phospatase, and gamma-glutamyltransferase levels in groups C and D (obstructive jaundice groups) were higher than those in groups A and B (sham groups; p < 0.05). There was no difference between groups A and B (sham groups) with regard to the number of cells expressing surface CD44 in jejunum and ileum. When groups A and B were compared with group C (obstructive jaundice + saline) animals, the number of cells expressing surface CD44 was significantly decreased in both jejunum and ileum in group C. The difference between sham groups (A and B) and group C was found to be significant (p < 0.05). When group D (obstructive jaundice + vitamin A) was compared with group C (obstructive jaundice + saline), the number of cells expressing surface CD44 was significantly increased in jejunum and ileum in group D animals (p < 0.05), higher than in the sham groups (A and B). The difference between group D and sham groups (A and B) was found to be significant (p < 0.05).

Conclusion: Obstructive jaundice for 2 weeks significantly decreased the CD44 expression in the rat small intestine. We found that daily intraperitoneal administration of vitamin A in rats with obstructive jaundice for 2 weeks significantly restored the impaired CD44 expression.