Effect of rhubarb polysaccharide combined with semen crotonis pulveratum on intestinal lymphocyte homing in rats with TNBS-induced colitis

This study aimed to explore the influence of the combination of rhubarb polysaccharide and semen crotonis pulveratum on lymphocyte homing in the intestinal mucosa of ulcerative colitis (UC) rats. A rat colitis model was induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS). Rats were allocated to the control group, the model group, the salazosulfapyridine group, the semen crotonis pulveratum+ rhubarb polysaccharide high dose group (B+R80 group), the moderate group (B+R60 group), and the low group (B+R40 group) (all n=10). Flow cytometry detected CD3+, CD4+, CD8+ and the CD4+/CD8+ ratio in peripheral blood and the lamina propria of the intestinal mucosa. Mucosal addressin cell adhesion molecule-1 (MAdCAM-1) mRNA in intestinal mucosal tissues was monitored with RT-PCR. Lymphocyte function-related molecule (alpha L beta 2) and intercellular adhesion molecule-1 (ICAM-1) were detected by immunohistochemistry in colon tissues. Compared with the model group, CD8+ levels in the peripheral blood from the B+R40, B+R60, and B+R80 groups increased (P<0.05), and the CD4+/CD8+ ratio decreased (P<0.01). CD4+ and CD4+/CD8+ ratio in the intestinal mucosa were increased (P<0.01), and the difference was most notable in the B+R40 group. The colon macroscopic damage index score decreased to different degrees (P<0.05), histopathologic score decreased (P<0.01), and the expression of MAdCAM-1 decreased. The expression of ICAM-1 was significantly decreased (P<0.05), but similar between groups (P>0.05). alpha L beta 2 expression was significantly decreased in the B+R80 and B+R40 groups (P<0.01). Rhubarb polysaccharide and semen crotonis pulveratum in combination decreased damage to the intestinal mucosa by regulating homing of lymphocytes in UC rats to improve the immune function of the mucosa.