NOX1/NADPH oxidase in bone marrow-derived cells modulates intestinal barrier function
NOX1/NADPH oxidase in bone marrow-derived cells modulates intestinal barrier function
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DOI：
10.1016/j.freeradbiomed.2019.12.009
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发表时间：
2020-02-01
影响因子：
7.4
通讯作者：
Yabe-Nishimura, Chihiro
中科院分区：
文献类型：
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作者：
Liu, Junjie;Iwata, Kazumi;Yabe-Nishimura, Chihiro
活性氧（ROS）参与炎症性肠病（IBD）的发展。肠屏障功能受损在IBD患者中很常见。在这里，我们报告的核心作用的NOX 1/NADPH氧化酶，在非吞噬细胞的ROS的主要来源，在肠道屏障功能障碍。通过使用L-012作为探针的体内成像，在施用脂多糖（LPS：6 mg/kg i. p.）的野生型小鼠（WT）的腹部中证实了ROS的时间依赖性增加，但在Nox 1（Nox 1-KO）或诱导型一氧化氮合酶基因（iNOS-KO）缺陷的小鼠中，它几乎完全消失。通过离体成像，增加的ROS产生主要在回肠中显示，其中在上皮的顶侧上观察到增强的NOX 1免疫染色。另一方面，在固有层中证明了3-硝基酪氨酸（过氧亚硝酸盐产生的标志物）的点状染色模式。当通过口服异硫氰酸荧光素结合葡聚糖（FD-4）评估LPS诱导的肠通透性过高时，Nox 1-KO和iNOS-KO均受到显著抑制。当用WT骨髓过继转移Nox 1-KO时，用LPS处理时，血清FD-4水平显著升高，而接受来自Nox 1-KO的骨髓的WT中FD-4水平保持不变。同时，LPS诱导的肠组织和腹腔巨噬细胞基质金属蛋白酶-9的活化也明显减轻。在Nox 1缺陷的巨噬细胞中，LPS对iNOS的上调显著抑制，说明了NOX 1/iNOS信号传导的功能层次。总之，这些发现表明，在骨髓来源的细胞，而不是上皮细胞中的NOX 1，在内毒素血症期间扰乱肠屏障的完整性。
The involvement of reactive oxygen species (ROS) has been suggested in the development of inflammatory bowel disease (IBD). An impaired intestinal barrier function is common in IBD patients. Here, we report the central role of NOX1/NADPH oxidase, a major source of ROS in nonphagocytic cells, in intestinal barrier dysfunction. By in vivo imaging using L-012 as a probe, a time-dependent increase in ROS was demonstrated in the abdomen of wild-type mice (WT) administered lipopolysaccharide (LPS: 6 mg/kg i.p.), but it was almost completely abolished in mice deficient in Nox1 (Nox1-KO) or the inducible nitric oxide synthase gene (iNOS-KO). By ex vivo imaging, increased ROS production was mainly shown in the ileum, where enhanced immunostaining of NOX1 was observed on the apical side of the epithelium. On the other hand, a punctate staining pattern of 3-nitrotyrosine, a marker of peroxynitrite production, was demonstrated in the lamina propria. When LPS-induced intestinal hyperpermeability was assessed by the oral administration of fluorescein isothiocyanate-conjugated dextran (FD-4), it was significantly suppressed in Nox1-KO as well as iNOS-KO. When Nox1-KO adoptively transferred with WT bone marrow were treated with LPS, the serum level of FD-4 was significantly elevated, whereas it remained unchanged in WT receiving bone marrow derived from Nox1-KO. Concomitantly, the activation of matrix metalloproteinase-9 induced by LPS was alleviated not only in intestinal tissue but also in peritoneal macrophages of Nox1-KO. Up-regulation of iNOS by LPS was significantly inhibited in macrophages deficient in Nox1, illustrating a functional hierarchy in NOX1/iNOS signaling. Together, these findings suggest that NOX1 in bone marrow-derived cells, but not epithelial cells, perturbs intestinal barrier integrity during endotoxemia.