幽门螺杆菌和非甾体消炎药对胃上皮细胞动力学的影响

Effects of Helicobacter pylori and NSAIDs on cytokinetics of gastric epithelium

目的:观察幽门螺杆菌(H pylori)和非甾体消炎药(NSAID)对胃上皮细胞增生凋亡的影响. 方法:胃癌细胞株AGS与H pylori和/或消炎痛,阿司匹林体外共培养,通过MTT比色法,增生细胞核抗原(PCNA) 的Western Blotting检测技术,观察细胞增生情况,FITC- Annexin-V/PI双染色流式细胞仪检测,DNA凝胶电泳, 透射电镜方法等检测细胞凋亡. 结果:MTT比色法和蛋白质印迹检测细胞PCNA表达结果表明细胞毒素相关基因A(CagA)阳性的H pylori菌株NCTC11637能够促进细胞增生,此外,低密度(3.2 ×107-4×109CFU/L)NCTC11637能促进细胞的增生,而高浓度(>2 ×1010CFU/L)则抑制细胞的增生.消炎痛和阿司匹林能抑制细胞的活力.当AGS细胞与H pylori和NSAID共同孵育时,细胞的生长亦明显受到抑制.FITC-Annexin- V/PI双染色流式细胞仪检测表明消炎痛和阿司匹林可诱导细胞凋亡明显增强,而H pylori组则未见凋亡的增强,当二者共同作用于AGS细胞时,细胞凋亡率明显升高,但与非甾体消炎药单独作用组相比,则有所下降.透射电镜和DNA琼脂糖凝胶电泳进一步证实了FITC-Annexin-V/PI双染色流式细胞仪检测的结果. 结论:CagA阳性H Hpylori更加容易促进胃上皮细胞的增生.H pylori对细胞生长的影响与H pylori的密度有关. H pylori和NSAID间的作用是相互拮抗的.

AIM: To investigate the effects of Helicobacter pylori (H pylori) and (NSAID) indomethacin and aspirin on the proliferation and apoptosis of gastric epithelial cells METHODS: Gastric cancer cell line AGS cells were co-cultured with H pyloriand/or NSAID, and then proliferation of AGS was examined by MTT assay, Western blotting and detection of proliferating cell nuclear antigen (PCNA). At the same time, cell apoptosis was detected with the FITC-Annexin-V/PI double staining, DNA gel eletrophoresis and transmission electron microscopy were used to confirm the results. RESULTS: The CagA-positive H pylori strain NCTC11637 could enhance cell proliferation. Besides, low concentrations (range from 3.2×107 CFU/L to 4×109 CFU/L) of H pylori could promote proliferation (P<0.05) of AGS cell line while high concentrations (>2×1010 CFU/L) could inhibit the growth of AGS cells (P<0.05). When incubated with H pylori and NSAID together, proliferation of AGS cells was inhibited. Indomethacin and aspirin increased apoptosis of AGS cells significantly (P <0.05). No obvious apoptosis was observed in the H pylori-infected cells. When cells were co-cultured with H py/ori and NSAID, the percentage of apoptosis also increased significantly (P <0.05), but the percentage was lower than that of cells incubated with NSAID alone. These results were confirmed by transmission electron microscopy and DNA gel electrophoresis. CONCLUSION: CagA(+)H pylori strains are more prone to enhance the proliferation of gastric epithelial cells than cagA(-) H pylori strains. The effects of H pylori on the cell growth are associated with the concentrations of H pylori. NSAID can inhibit the gastric epithelial cell proliferation.