Neutrophil Extracellular Traps Induce Trypsin Activation, Inflammation, and Tissue Damage in Mice With Severe Acute Pancreatitis
Neutrophil Extracellular Traps Induce Trypsin Activation, Inflammation, and Tissue Damage in Mice With Severe Acute Pancreatitis
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DOI：
10.1053/j.gastro.2015.08.026
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发表时间：
2015-12-01
期刊：
影响因子：
29.4
通讯作者：
Thorlacius, Henrik
中科院分区：
文献类型：
--
作者：
Merza, Mohammed;Hartman, Hannes;Thorlacius, Henrik
背景与目的：中性粒细胞参与急性胰腺炎（AP）的发生，但尚不清楚中性粒细胞诱导的组织损伤是如何调节的。除了分泌抗菌化合物外，活化的中性粒细胞还通过排出核 DNA 和组蛋白形成称为中性粒细胞胞外陷阱 (NET) 的胞外网状结构来消除入侵的微生物。然而，据报道，NETs 会导致传染病患者的器官功能障碍。我们研究了 NET 是否有助于小鼠 AP 的发生。方法：通过将牛磺胆酸盐注入胰管或腹膜内注射 L-精氨酸，在 C57BL/6 小鼠中诱导 AP。收集胰腺并通过Sytox绿染色检测细胞外DNA，还测量CXC趋化因子、组蛋白和细胞因子的水平。对血浆样品中的游离 DNA 进行定量。在分离的腺泡细胞中分析了转录3磷酸化和胰蛋白酶激活的信号转导器和激活剂。通过给小鼠注射 DNase I 来耗尽 NET。血浆取自健康个体（对照）和严重 AP 患者。结果：输注牛磺胆酸盐诱导小鼠胰腺组织中 NET 的形成，并增加血浆中游离 DNA 的水平。中性粒细胞耗竭可防止牛磺胆酸盐诱导的 NET 在胰腺中沉积。给小鼠注射 DNase I 可以减少发炎的胰腺和肺中的中性粒细胞浸润和组织损伤，并降低血液淀粉酶、巨噬细胞炎症蛋白 2、白细胞介素 6 和高迁移率族蛋白 1 的水平。在给予牛磺胆酸盐的小鼠中，注射 DNase I 还可以减少循环中性粒细胞上整合素 α M（巨噬细胞 1 抗原）的表达。在 L-精氨酸诱导的 AP 小鼠中也出现了类似的结果。向腺泡细胞中添加 NET 和组蛋白可诱导胰蛋白酶的形成以及信号转导器和转录激活剂的激活 3；这些过程被聚唾液酸阻断。与对照组相比，严重 AP 患者的血浆 NET 成分水平升高。结论：在 AP 发生过程中，小鼠胰腺中形成 NET，并且与对照组相比，AP 患者血浆中 NET 水平升高。 NETs 调节患有 AP 的小鼠的器官炎症和损伤，并且可能有针对性地减少患者的胰腺组织损伤和炎症。
BACKGROUND & AIMS: Neutrophils are involved in the development of acute pancreatitis (AP), but it is not clear how neutrophil-induced tissue damage is regulated. In addition to secreting antimicrobial compounds, activated neutrophils eliminate invading microorganisms by expelling nuclear DNA and histones to form extracellular web-like structures called neutrophil extracellular traps (NETs). However, NETs have been reported to contribute to organ dysfunction in patients with infectious diseases. We investigated whether NETs contribute to the development of AP in mice. METHODS: AP was induced in C57BL/6 mice by infusion of taurocholate into the pancreatic duct or by intraperitoneal administration of L-arginine. Pancreata were collected and extracellular DNA was detected by Sytox green staining, levels of CXC chemokines, histones, and cytokines also were measured. Cell-free DNA was quantified in plasma samples. Signal transducer and activator of transcription 3 phosphorylation and trypsin activation were analyzed in isolated acinar cells. NETs were depleted by administration of DNase I to mice. Plasma was obtained from healthy individuals (controls) and patients with severe AP. RESULTS: Infusion of taurocholate induced formation of NETs in pancreatic tissues of mice and increased levels of cell-free DNA in plasma. Neutrophil depletion prevented taurocholate-induced deposition of NETs in the pancreas. Administration of DNase I to mice reduced neutrophil infiltration and tissue damage in the inflamed pancreas and lung, and decreased levels of blood amylase, macrophage inflammatory protein-2, interleukin 6, and high-mobility groups protein 1. In mice given taurocholate, DNase I administration also reduced expression of integrin alpha M (macrophage-1 antigen) on circulating neutrophils. Similar results occurred in mice with L-arginine-induced AP. Addition of NETs and histones to acinar cells induced formation of trypsin and activation of signal transducer and activator of transcription 3; these processes were blocked by polysialic acid. Patients with severe AP had increased plasma levels of NET components compared with controls. CONCLUSIONS: NETs form in the pancreata of mice during the development of AP, and NET levels are increased in plasma from patients with AP, compared with controls. NETs regulate organ inflammation and injury in mice with AP, and might be targeted to reduce pancreatic tissue damage and inflammation in patients.