中文摘要：

目的：探讨c-Jun氨基末端蛋白激酶（JNK）在氢气改善重度脓毒症小鼠肠屏障功能障碍中的作用。方法将80只雄性ICR小鼠按照随机数字表法分为假手术组、氢气对照组、脓毒症组和氢气治疗组，每组20只。采用盲肠结扎穿孔术（CLP）制备重度脓毒症小鼠模型，假手术组和氢气对照组只进行开腹手术而不行盲肠结扎和穿孔。氢气对照组和氢气治疗组于制模后1h和6h分别吸入2%的氢气1h。于制模后20h时各组取10只，向胃内灌注异硫氰酸荧光素标记的右旋糖酐（FITC-右旋糖酐），4 h后经心脏穿刺取血并测定血清FITC-右旋糖酐水平。于制模后24 h各组取10只，取腹腔液进行细菌培养并计数菌落形成单位（CFU）；取中段小肠组织，采用酶联免疫吸附试验测定肠组织肿瘤坏死因子（TNF）-α、白细胞介素（IL）-1β和高迁移率族蛋白1（HMGB1）水平，采用蛋白免疫印迹法测定肠组织JNK的磷酸化水平（p-JNK）以及紧密连接蛋白ZO-1和Occludin的表达，利用光学显微镜和透射电镜分别观察肠组织病理学改变和肠上皮细胞超微结构的变化。结果假手术组和氢气对照组各指标差异均无统计学意义。与假手术组比较，脓毒症组血清FITC-右旋糖酐、腹腔液细菌培养菌CFU和小肠组织TNF-α、IL-1β和HMGB1明显增加，小肠组织p-JNK表达明显增加并伴随ZO-1和Occludin表达下调（均P〈0.05），小肠组织明显损伤伴肠上皮细胞超微结构严重受损。与脓毒症组比较，氢气治疗组制模后24 h时血清FITC-右旋糖酐、腹腔液细菌培养CFU和小肠组织TNF-α、IL-1β和HMGB1明显降低，小肠组织p-JNK表达下调并伴随ZO-1和Occludin表达增加（均P〈0.05），小肠组织损伤和肠上皮细胞超微结构受损明显减轻。结论氢气可以通过抑制JNK通路降低小肠组织炎症因子的水平并增加紧密连接蛋白的表达，从而改善重度脓毒症引起的肠?

英文摘要：

Objective To investigate the role of JNK in intestinal barrier dysfunction in severe septic mice treated by hydrogen. Methods Eighty male ICR mice were randomly divided into four groups （n=20 each）：sham operation group, hydrogen control group, sepsis group and hydrogen treatment group. Severe sepsis rat model was reproduced by cecal ligation and puncture （CLP）. Laparotomy without CLP was performed in sham operation group and hydrogen control group. The mice in hydrogen control group and hydrogen treatment group received 1-hour inhalation of 2%hydrogen at 1 hour and 6 hours after sham operation or CLP, respectively. Ten mice of each group were selected at 20 h after CLP operation and were gavaged with fluorescein-isothiocyanate-conjugated dextran （FITC-dextran）. Blood samples were obtained by cardiac puncture to measure the serum concentration of FITC-dextran 4 h after treatment with FITC-dextran . Ten mice in each group were sacrificed at 24 h after CLP operation. The colony-forming unit （CFU） numbers in the peritoneal lavage fluid were counted. The middle intestinal tissues were obtained for the measurement of tumor necrosis factor alpha （TNF-α）, interleukin （IL）-1βand high mobility group box 1（HMGB1） by ELISA. The level of phosphorylated JNK （p-JNK） and the expression of tight junction protein ZO-1 and Occludin were detected by Western blot assay. The intestinal pathological changes and epithelial ultrastructure changes were observed by light microscope and transmission electron microscope （TEM）. Results There was no statistical significance in clinical variables between sham operation group and hydrogen control group. Compared with sham operation group, the serum FITC-dextran concentration, the CFU numbers in the peritoneal lavage fluid, the levels of TNF-α, IL-1βand HMGB1 in intestine, and the expression of p-JNK were significantly increased, the expression of ZO-1 and Occludin were down-regulated in sepsis group（P 〈 0.05）. There was a significant intestinal pat