脓毒症大鼠高迁移率族蛋白-1对组织Toll样受体2基因表达的影响

Effect of tissue high mobility group box-1 protein on Toll-like receptor 2 gene expression in septic rats

目的 探讨高迁移率族蛋白 - 1(HMGB - 1)对组织Toll样受体 2 (TLR2 )基因表达的影响及其与机体炎症反应平衡的关系。 方法 采用大鼠盲肠结扎穿孔 (CLP)模型造成脓毒症。5 0只大鼠随机分为正常对照组 (10只 )、CLP组 (2 0只 )及HMGB - 1抑制剂正丁酸钠治疗组 (2 0只 )。分别检测肝、肺、肾组织HMGB - 1 TLR2mRNA表达、TNF -α 白细胞介素 - 10 (IL - 10 )蛋白水平。 结果 正丁酸钠治疗组CLP后 12及 2 4h肝、肺、肾组织TLR2mRNA表达均较CLP组显著下调 (P <0 .0 5～ 0 .0 1) ,且肝、肺、肾组织HMGB - 1mRNA表达与相应组织TLR2mRNA表达均呈显著正相关 (分别为r=0 .5 5 6 ,P =0 .0 0 0 ;r=0 .46 2 ,P =0 .0 0 0 ;r=0 .40 2 ,P =0 .0 0 1)。同时 ,CLP术后给予正丁酸钠治疗 2 4h肺、肾组织TNF -α蛋白表达显著降低 (P <0 .0 5～ 0 .0 1) ,而肝、肺、肾组织IL - 10水平则呈现不同程度的升高 (P <0 .0 5～ 0 .0 1)。 结论 严重腹腔感染后组织HMGB - 1可显著促进TLR2mRNA表达 ,应用HMGB - 1合成抑制剂干预有助于调节体内致炎 抗炎反应平衡。

Objective To investigate the effect of tissue high mobility group box-1 protein (HMGB-1) on Toll-like receptor 2 (TLR2) gene expression in septic rats and its relation to inflammatory response balance. Methods Cecal ligation puncture (CLP) model was used to produce sepsis in rats. A total of 50 Wistar rats were randomly divided into normal control group (n=10), CLP group (n=20) and CLP plus sodium butyrate treatment group (n=20). Tissue samples from the liver and the lungs as well as the kidneys were harvested to determine the expressions of HMGB-1 and TLR-2 mRNA by reverse-transcription PCR and the tissue TNF-α/interleukin-10 (IL-10) protein levels by ELISA. Results Compared with CLP group, treatment with CLP plus sodium butyrate could significantly down-regulate TLR2 mRNA expression in the liver, the lungs and the kidneys at the 12th and 24th hours following CLP (P<0.05～0.01). Meanwhile, HMGB-1 expressions in the liver, the lungs and the kidneys were positively correlated with TLR2 mRNA expression (liver: r=0.556, P=0.000; lungs: r=0.462, P=0.000; kidneys: r=0.402, P=0.001). Posterior to CLP, in animals treated with sodium butyrate, TNF-α protein levels were significantly decreased in the lungs and the kidneys (P<0.05～0.01), while IL-10 levels were markedly increased in these tissues at the 24th hour (P<0.05～0.01). Conclusions HMGB-1 induction in vital organs may be critically involved in the up-regulation of TLR2 mRNA expression in sepsis induced by CLP. Treatment with synthetic inhibitor HMGB-1 can improve the balance between pro- and anti-inflammatory responses in various tissues in septic rats.