核因子κB"诱饵"寡核苷酸对小鼠葡聚糖硫酸钠结肠炎的影响

目的 探讨核因子κB“诱饵”寡核苷酸（NF-κB Decoy ODN）对葡聚糖硫酸钠（DSS）结肠炎的影响,为寻找一种治疗溃疡性结肠炎（UC）的新药提供实验依据.方法36只BALB/C小鼠按编号抽签随机分为：正常对照组;DSS＋NF-κB“诱饵”ODN组;DSS＋错配物ODN组;DSS＋生理盐水组,每组9只.方法（1）测定各组小鼠血清中尿素氮、肌酐、随机血糖、丙氨酸氨基转移酶、天冬氨酸氨基转移酶浓度.（2）取小鼠结肠组织进行大体及组织形态学观察.（3）免疫组织化学染色观察NF-κB p65在结肠黏膜细胞内的表达.（4）酶联免疫吸附法（ELISA）测定结肠黏膜组织中肿瘤坏死因子α（TNF-α）的含量.（5）共聚焦显微镜观测NF-κB“诱饵”ODN在小鼠结肠黏膜内的分布.结果（1）5%DSS处理的3组小鼠的DAI评分和组织学评分及肠黏膜组织内TNF-α表达均明显高于正常对照组（均P＜0.05）;而NF-κB“诱饵”ODN组的上述指标均明显低于错义NF-κB“诱饵”ODN组和生理盐水组（均P＜0.01）.（2）5%DSS处理的3组小鼠其肠黏膜组织NF-κB p65的表达以胞核为主,而且这3组间NF-κB p65胞核表达差异无统计学意义.相反,正常对照组小鼠NF-κB p65以胞质表达为主.（3）NF-κB诱饵ODN可有效进入小鼠结肠黏膜层和黏膜下层组织.（4）各实验组小鼠肝、肾功能及血糖比较差异无统计学意义.结论NF-κB“诱饵’ODN对小鼠DSS结肠炎有较好的保护作用.

The effects of nuclear factor-kappaB decoy oligonucleotides on dextran sulphate sodium-induced colitis: experiment with mice

OBJECTIVE: To investigate the effects of nuclear factor-kappaB (NF-kappaB) decoy oligonucleotide (ODN) on dextran sulphate sodium (DSS)-induced colitis. METHODS: Nine female BABL/C mice underwent infusion of 0.15 ml normal saline into the distant colon and used as controls (Group 1). Twenty-seven female BABL/C mice were made into DSS-induced colitis models and then randomly divided into 3 groups: Group 2 (underwent infusion of 0.15 ml normal saline into the distant colon), Group 3 (infused with NF-kappaB decoy ODN 25 nmol solved in 0.15 ml), and Group 4 (infused with NF-kappaB scrambled decoy ODN 25 nmol solved in 0.15 ml). Disease active index (DAI) was observed every day. Nine days later the mice were killed and their colons were taken out to undergo histological examination. The tumor necrosis factor (TNF)-alpha level of the colon mucosa was measured by enzyme linked immunosorbent assay (ELISA). NF-kappaB expression was determined by immunohistochemical staining. The distribution of NF-kappaB decoy ODN was investigated by confocal laser microscopy. RESULTS: (1) The DAI scores, histological scores and TNF-a level in the colon mucosa of Groups 2 - 4 were all significantly higher than those of Group 1 (all P < 0.05). The DAI scores, histological scores and TNF-a level in the colon mucosa of Group 3 were all significantly lower than those of Groups 2 and 4 (all P < 0.01). (2) In the tissue sections NF-kappaB p65 was positive mainly in the nucleus in the 3 DSS-treated groups without significant differences among these 3 groups, and was mainly positive in the cytoplasm in the control group. (3) Confocal laser microscopy showed that NF-kappaB decoy ODN could be ingested efficiently into the mucosa and submucous layer of colon. (4) There were no significant differences in the liver function, kidney function, and blood glucose among all groups. CONCLUSION: NF-kappaB pathway is associated with the pathogenesis of DSS-induced colitis which is very similar to human UC. Blockade of NF-kappaB pathway by NF-kappaB decoy ODN shows protective effect on the mice with DSS-induced colitis.