Modulation of dendritic cells phenotype by Astragalus polysaccharides in experimental colitis in rats / 中华临床营养杂志

ABSTRACT

Objective To investigate the effect of Astragalus polysaccharides (APS) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats and on dendritic cells (DCs) in mesenteric lymph nodes.Methods Forty-four male Sprague-Dawley rats were randomly divided into four groups (n = 11) using simple random sampling normal control group, TNBS group, APS group, and 5-aminosalicylic acid (5-ASA) group.Experimental colitis was induced in rats by TNBS enema in the last three groups.Rats in APS and 5-ASA groups were treated by gavage with APS (0.75 g ? kg-1 ? d-1) and 5-ASA (100 mg ? kg-1 ? d-1) on the 10 consecutive days following TNBS administration.The rats were then sacrificed and the colonic inflammatory scores of rats were measured, including the scores of disease activity index ( DAI) , macroscopic lesions, and histological damages,as well as the activity of myeloperoxidase (MPO).The expressions of major histocompatibility complex class Ⅱ(MHC Ⅱ ) and costimulatory molecule CD86 on DCs were determined by flow cytometry.Results Compared with the TNBS group, APS group had significantly decreased scores of DAI ( P = 0.007 ) , macroscopic lesions (P =0.017), and histological damages (P = 0.016).Moreover, its level of the activity of MPO dropped but without statistical significance (P =0.183).TNBS group had significantly higher expressions of MHC Ⅱand CD86 molecules on DCs than the normal control group (P = 0.005, P = 0.008), APS group (P = 0.023, P = 0.018), and 5-ASA group (P = 0.017, P=0.013).Conclusion APS may attenuate TNBS-induced colitis in rats and downregulate the activation of DCs in mesenteric lymph nodes.