Department of Pediatric Surgery, University Medical Center Hamburg-Eppendorf, Martini Strasse 52, 20246 Hamburg, Germany.
Department of Pediatric Surgery, University Medical Center Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
Int J Mol Sci. 2024 Mar 28;25(7):3787. doi: 10.3390/ijms25073787.
A better understanding of the function of neutrophil extracellular traps (NETs) may facilitate the development of interventions for sepsis. The study aims to investigate the formation and degradation of NETs in three murine sepsis models and to analyze the production of reactive oxygen species (ROS) during NET formation. Murine sepsis was induced by midgut volvulus (720° for 15 min), cecal ligation and puncture (CLP), or the application of lipopolysaccharide (LPS) (10 mg/kg body weight i.p.). NET formation and degradation was modulated using mice that were genetically deficient for -KO) or and -DKO). After 48 h, mice were killed. Plasma levels of circulating free DNA (cfDNA) and neutrophil elastase (NE) were quantified to assess NET formation and degradation. Plasma deoxyribonuclease1 (DNase1) protein levels, as well as tissue malondialdehyde (MDA) activity and glutathione peroxidase (GPx) activity, were quantified. DNase1 and DNase1L3 in liver, intestine, spleen, and lung tissues were assessed. The applied sepsis models resulted in a simultaneous increase in NET formation and oxidative stress. NET formation and survival differed in the three models. In contrast to LPS and Volvulus, CLP-induced sepsis showed a decreased and increased 48 h survival in -KO and -DKO mice, when compared to WT mice, respectively. -KO mice showed decreased formation of NETs and ROS, while -DKO mice with impaired NET degradation accumulated ROS and chronicled the septic state. The findings indicate a dual role for NET formation and degradation in sepsis and ischemia-reperfusion (I/R) injury: NETs seem to exhibit a protective capacity in certain sepsis paradigms (CLP model), whereas, collectively, they seem to contribute adversely to scenarios where sepsis is combined with ischemia-reperfusion (volvulus).
更好地了解中性粒细胞胞外诱捕网(NETs)的功能可能有助于开发脓毒症的干预措施。本研究旨在研究三种小鼠脓毒症模型中 NETs 的形成和降解,并分析 NET 形成过程中活性氧(ROS)的产生。通过中肠扭转(15 分钟 720°)、盲肠结扎和穿刺(CLP)或脂多糖(LPS)(10 mg/kg 体重腹腔注射)诱导小鼠脓毒症。使用基因缺陷型小鼠(-/-)或 -/-)来调节 NET 的形成和降解。48 小时后,处死小鼠。定量检测循环游离 DNA(cfDNA)和中性粒细胞弹性蛋白酶(NE)的血浆水平,以评估 NET 的形成和降解。定量检测血浆脱氧核糖核酸酶 1(DNase1)蛋白水平以及组织丙二醛(MDA)活性和谷胱甘肽过氧化物酶(GPx)活性。评估肝、肠、脾和肺组织中的 DNase1 和 DNase1L3。应用的脓毒症模型导致 NET 形成和氧化应激的同时增加。三种模型中的 NET 形成和存活不同。与 LPS 和 Volvulus 相反,CLP 诱导的脓毒症中 -/-和 -/-小鼠的 48 小时存活率分别较 WT 小鼠降低和升高。-/-小鼠的 NET 形成和 ROS 减少,而 NET 降解受损的 -DKO 小鼠积累 ROS 并记录脓毒症状态。研究结果表明 NET 形成和降解在脓毒症和缺血再灌注(I/R)损伤中具有双重作用:NETs 在某些脓毒症模型(CLP 模型)中似乎具有保护作用,而它们共同作用则可能对脓毒症与缺血再灌注相结合的情况产生不利影响(Volvulus)。