脂多糖对肠上皮细胞Syndecan-1表达的影响

Effect of Lipopolysaccharide on Expression of Syndecan-1 in Intestinal Epithelial Cells

背景：Syndecan-1是表达于肠上皮细胞的跨膜糖蛋白，与炎症密切相关，但其在肠道非特异性炎症中的机制未明。脂多糖（LPS）在感染和炎症中均起重要作用。目前关于两者在肠道炎症中关系的研究尚少。目的：探讨LPS对肠上皮细胞Syndecan-1表达的影响。方法：体外培养人结直肠癌细胞株SW480、LoVo和HT-29．以流式细胞仪检测Syndecan-1表达，以细胞免疫荧光观察不同剂量LPS（0-10^4ng／ml）对SW480细胞Syndecan-1表达的影响。结果：SW480细胞中Syndecan—1表达显著高于其余两种细胞株。随着LPS剂量增高，Syndecan-1表达降低，作用呈剂量依赖性。结论：LPS可能通过抑制Syndecan-1表达而参与肠道炎症的过程。

Background：Syndecan-1 is a transmembrane proteoglycan mainly expressed on the surface of intestinal epithelial cells, and is closely related with inflammation, but its mechanism in the pathogenesis of nonspecific intestinal inflammation is unclear. Lipopolysaccharide （LPS） plays an important role in the infection and inflammation, but there are few studies on the relationship between Syndecan-1 and LPS in intestinal inflammation. Aims： To appraise the effect of LPS on expression of Syndecan-1 in intestinal epithelial cells. Methods： Human colorectal carcinoma cell lines SW480, LoVo and HT-29 were cultured in vitro, and the expression of Syndecan-1 in their colorectal carcinoma epithelial cell lines was measured by flow cytometry. The influence of different doses of LPS （from 0 ng/ml to 10^4 ng/ml） on the expression of Syndecan-1 in SW480 cells were observed by immunofluorescence. Results： The expression of Syndecan-1 in SW480 cells was significantly higher than that in the other two cell lines. The expression of Syndecan-1 decreased significantly in the presence of different doses of LPS in a dose-dependent manner. Conclusions： LPS may participate in the process of intestinal inflammation via the down-regulation of expression of Syndecan-1.