General Practice Department of Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Emergency Department of Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
Int Arch Allergy Immunol. 2022;183(9):997-1006. doi: 10.1159/000524272. Epub 2022 May 6.
Vascular endothelial hyperpermeability and barrier disruption are involved in the initiation and development of sepsis. M1 macrophages promote inflammation in sepsis by releasing pro-inflammatory cytokines and chemokines. This study was designed to investigate the functional relationships between M1 macrophages and human umbilical vein endothelial cells (HUVECs), as well as the underlying molecular mechanisms.
HUVECs were co-cultured with THP-1-derived M1 macrophages pretreated with or without rosiglitazone (RSG), a peroxisome proliferator-activated receptor (PPAR)-γ agonist. C-X-C chemokine receptor type (CXCR)5 was knocked down by short hairpin RNA lentivirus. Cecal ligation and puncture were used to induce sepsis in a mouse model. Endothelial permeability was evaluated using transendothelial electrical resistance and fluorescein isothiocyanate (FITC)-dextran assays.
Chemokine ligand (CXCL)13 was upregulated in M1 macrophages than M0 macrophages, as well as in the culture medium. In HUVECs co-cultured with M1 macrophages, transendothelial electrical resistance decreased, FITC-dextran flux increased, p38 phosphorylation was strengthened, and the expression of tight junction proteins (zonula occludens protein-1, occludin, and claudin-4) decreased. CXCR5 RNA interference or RSG pretreatment partially reversed these effects. A luciferase reporter assay revealed that CXCL13 was a direct target of PPAR-γ. RSG treatment decreased serum levels of creatinine, blood urea nitrogen, CXCL13, tumor necrosis factor-α, and interleukin-6, downregulated CXCL13 in peritoneal macrophages, and enhanced the survival rate of sepsis mice.
M1 macrophages induced endothelial hyperpermeability and promoted p38 phosphorylation in sepsis by inhibiting PPAR-γ to increase CXCL13 production. PPAR-γ/CXCL13-CXCR5 signaling could be a promising novel therapeutic target for sepsis.
血管内皮通透性增加和屏障破坏参与了脓毒症的发生和发展。M1 巨噬细胞通过释放促炎细胞因子和趋化因子促进脓毒症中的炎症反应。本研究旨在探讨 M1 巨噬细胞与人类脐静脉内皮细胞（HUVEC）之间的功能关系及其潜在的分子机制。
将 HUVEC 与经过罗格列酮（RSG）预处理或未预处理的 THP-1 衍生的 M1 巨噬细胞共培养，RSG 是一种过氧化物酶体增殖物激活受体（PPAR）-γ激动剂。用短发夹 RNA 慢病毒敲低 C-X-C 趋化因子受体类型（CXCR）5。使用盲肠结扎和穿孔法在小鼠模型中诱导脓毒症。通过跨内皮电阻和荧光素异硫氰酸酯（FITC）-葡聚糖测定评估内皮通透性。
与 M0 巨噬细胞相比，M1 巨噬细胞中趋化因子配体（CXCL）13 的表达上调，且在培养上清液中也上调。在与 M1 巨噬细胞共培养的 HUVEC 中，跨内皮电阻降低，FITC-葡聚糖通量增加，p38 磷酸化增强，紧密连接蛋白（闭锁蛋白-1、occludin 和 claudin-4）的表达减少。CXCR5 RNA 干扰或 RSG 预处理部分逆转了这些作用。荧光素酶报告基因检测显示，CXCL13 是 PPAR-γ 的直接靶标。RSG 处理降低了血清肌酐、尿素氮、CXCL13、肿瘤坏死因子-α和白细胞介素-6 的水平，下调了腹腔巨噬细胞中的 CXCL13，并提高了脓毒症小鼠的存活率。
M1 巨噬细胞通过抑制 PPAR-γ 抑制 CXCL13 的产生，导致内皮通透性增加，并促进 p38 磷酸化，从而在脓毒症中诱导内皮通透性增加。PPAR-γ/CXCL13-CXCR5 信号通路可能是脓毒症的一种有前途的新治疗靶点。
