地黄多糖对DSS诱导的小鼠溃疡性结肠炎的治疗作用OACSTPCD

Objective To investigate the effect and mechanism of raw rehmannia root polysaccharides(RRP),prepared rehmannia root polysaccharides(PRP),raw rehmannia root extract(RR),and prepared rehmannia root extract(PR)on dextran sodium sulfate(DSS)-induced ulcerative colitis(UC)in mice.Methods RR,PR,RRP and PRP were prepared,and the molecular weight and the monosaccharide composition of RRP and PRP were determined.Seventy ICR mice were randomly divided into control group,model group(DSS group),metharazine group(5-ASA group),RR group,PR group,RRP group,and PRP group,with 10 mice in each group.At days 1-7,all the mice drank 3％DSS except the mice in control group.At days 8-14,the mice in control group and DSS group drank sterile water,and the mice in 5-ASA group,RR group,RRP group,PR group and PRP group were given mesalazine,raw rehmannia root extract,raw rehmannia root polysaccharide,prepared rehmannia root extract and prepared rehmannia root polysaccha-ride at a dose of 200 mg/kg,respectively.During the experiment,the body weight,the fecal hardness and the rectal bleeding(disease activity index,DAI)of mice were recorded daily,and the colon length of mice was measured.HE staining was used to observe the pathological changes of colon tissue.And MPO activity and LPS level in colon tissue were determined by ELISA.Results The molecular weight of RRP and PRP included two kinds of about 200 kD and 4 kD.The polysaccharide of RRP was composed of glucose,galactose,galacturonic acid,mannose,rhamnose,xylose and fucose.And the PRP was composed of glucose,galactose,galacturonic acid,mannose,xylose and fucose.Compared with control group,the body weight was significantly decreased in DSS group(P＜0.000 1),the DAI score was significantly increased(P＜0.000 1),the colon length was shortened(P＜0.05),the spleen weight was increased(P＜0.000 1),and the MPO enzyme activity in colon tissue and the serum LPS content in the serum were increased(P＜0.05).Compared with DSS group,the DAI score was decreased in 5-ASA group,RR group,RRP group,PR group and PRP group(P＜0.05),especially in PRP group(P＜0.000 1).Compared with DSS group,the colon length was significantly increased in PR group(P＜0.05).Compared with DSS group,the spleen index was significantly decreased in 5-ASA group,RR group,PR group,RRP group and PRP group(P＜0.01),especially in RRP group and PRP group(P＜0.001).Compared with DSS group,the activity of MPO enzyme in colon was significantly decreased in RR group,RRP group,PR group and PRP group(P＜0.05),and the content of LPS in serum was significantly decreased in PR group(P＜0.05).Conclusion RR,RRP,PR and PRP can improve the pathological tissue of colon,and PRP and PR have a better therapeutic effect on UC in mice.