摘要
丝裂原活化蛋白激酶(MAPK)信号通路对重症急性胰腺炎(SAP)继发严重并发症起早期关键介导作用,相应抑制剂可改善SAP的病情。活化蛋白C(APC)具有改善SAP病情的作用,其具体机制尚未阐明。目的:观察APC对SAP大鼠MAPK信号通路中主要激酶的影响以及后续炎症介质的变化,为临床用药提供理论依据。方法:Sprague- Dawley大鼠诱导SAP模型后即刻静咏注射APC 10μg/kg或50μg/k。以基因芯片检测胰腺组织MAPK信号通路相关基因。以实时定量聚合酶链反应(real-time PCR)和蛋白质印迹法检测胰腺组织该通路中p38MAPK、c-Jun氨基端激酶/应激活化蛋白激酶(JNK/SAPK)、细胞外信号调节激酶(ERK)1/2 tuRNA、蛋白和磷酸化蛋白水平的表达,同时检测肿瘤坏死因子(TNF)-α和白细胞介素(IL)-1β蛋白的表达。结果:与APC治疗组和正常对照组相比,SAP组胰腺组织p38MAPK和JNK2 mRNA呈高表达与SAP组相比,50μg/kg APC治疗组p38MAPK、JNK/SAPK蛋白/磷酸化蛋白表达水平显著降低,ERK1/2蛋白/磷酸化蛋白表达水平显著升高,TNF-α和IL-1β蛋白表达水平显著降低(P均<0.05)。APC治疗组p38MAPK、磷酸化ERK1/2和TNF-α蛋白表达水平旱剂量依赖性(P均<0.05)。结论:APC可抑制SAP大鼠胰腺组织MAPK信号通路内p38MAPK和JNK/SAPK的表达和活化,进而抑制TNF-α和IL-1β的释放,同时上调ERK1/2的表达和活化,从而减轻膜腺组织损伤。
Background：Recent evidence indicates that mitogen-activated protein kinases （MAPK） act as an important signal transducer early in the pathogenesis of severe acute pancreatitis （SAP） associated with critical complications, and inhibitors of MAPK pathway can ameliorate the severity of SAP. Activated protein C （APC） administration may diminish the severity of SAP, but its mechanisms remain uncertain. Aims： To investigate the effects of APC on the major kinases in MAPK signal pathway, and the sequential changes of inflammatory mediators in SAP rats, thus providing evidences for clinical treatment of SAP by using APC. Methods： Sprague-Dawley rats were intravenously injected with 10 and 50μg/kg APC, respectively after induction of SAP. Genes involved in the pancreatic MAPK pathway were evaluated by cDNA microarray. The expression of p38MAPK, c-Jun-NH2-terminal kinase/stress activated protein kinase （JNK/SAPK） and extracellular signalregulated kinase （ERK） 1/2 at mRNA, protein and phosphorylated protein levels, and the protein levels of tumor necrosis factor （TNF）-α and interleukin （IL）-I[3 in pancreatic tissue were determined by real-time polymerase chain reaction （real-time PCR） or Western blot. Results： The mRNA levels of p38MAPK and JNK2 in pancreatic tissue increased in SAP group when compared with those in the APC-treated groups and normal control group. The protein/phosphorylated protein levels of p38MAPK and JNK/SAPK down-regulated and the protein/phosphorylated protein levels of ERKl/2 up-regulated in 50 μg/kg APC-treated group when compared with those in the SAP group （P〈0.05）, while the protein levels of TNF-α and IL-1β decreased （P〈0.01）. The protein levels of p38MAPK, phosphorylated ERK1/2 and TNF-α in APC-treated groups changed in a dose-dependent manner （P〈0.05）. Conclusions： Inhibition of pancreatic p38MAPK, JNK/SAPK, up-regulation of ERK1/2 and sequential suppression of TNF-α and IL-1β by APC can protect against pancreatic injury in SAP rats.
出处
《胃肠病学》
2007年第10期603-608,共6页
Chinese Journal of Gastroenterology
