脂多糖诱导小鼠肠组织ICAM-1表达的变化及p38MAPK在其中的作用

目的:研究脂多糖(LPS)诱导小鼠肠组织细胞间粘附分子-1(ICAM-1)表达的变化及p38丝裂原活化蛋白激酶(p38MAPK)在其中的调控作用。方法:用不同剂量的LPS或LPS加p38MAPK特异性抑制剂SB203580对小鼠进行不同时间的处理后, 分别采用Westernblot和RT-PCR检测ICAM-1蛋白和mRNA表达情况。结果:小鼠肠组织中ICAM-1蛋白和mRNA的表达在LPS剌激后显著高于对照组, LPS剌激后12-36h, ICAM-1表达增加最为显著。LPS剂量在20.0mg/kg时, 对ICAM-1的表达具有最大的剌激作用。SB203580预处理小鼠30min, 可显著抑制LPS诱导的ICAM-1蛋白和mRNA的表达。结论:LPS可诱导小鼠肠组织中ICAM-1蛋白和mRNA的表达增加, 并具有时间和剂量依赖性, p38MAPK信号转导通路可能在内毒素休克小鼠肠组织ICAM-1表达中起重要调节作用, 提示抑制p38MAPK通路可能对内毒素休克时肠损伤的防治有重要的意义。

Change of ICAM-1 expression in intestine tissue of mice induced by LPS and role of p38 MAPK in its expression

AIM: To study the change of intercellular adhesion molecule-1(ICAM-1) expression in intestine tissues of mice induced by LPS and regulatory effect of p38 mitogen-activated protein kinase (p38 MAPK) on ICAM-1 expression. METHODS: Protein and mRNA of ICAM-1 were measured using Western blotting and RT-PCR respectively in intestine tissue of BALB/c mice treated by lipopolysaccharide(LPS) or LPS plus SB203580, a specific inhibitor of p38 MAPK. RESULTS: Compared with control group, the expression of ICAM-1 protein and mRNA was increased significantly by LPS stimulation in dose- and time-dependent manner. ICAM-1 expression reached peak value at 12-36 h after LPS stimulation. 20.0 mg/kg of LPS could induce the maximum of ICAM-1 expression. Pretreatment of mice with SB203580 for 30 min could inhibit significantly LPS-induced expression of ICAM-1 protein and mRNA expression in mouse intestine tissues. CONCLUSIONS: These data highlight that LPS could up-regulate ICAM-1 protein and mRNA expression in intestine tissue of mice in dose- and time-dependent manner, and p38 MAPK signal pathway plays an important role in ICAM-1 expression induced by LPS. It suggests that inhibition of p38 MAPK might be a useful principle for the prevention and treatment of intestine damage of endotoxic shock.