Liu Qiuyuan, Wang Didi, Yang Xiaodong, Ma Fang, Han Wei, Hu Jing, Mei Qiao
Department of Gastroenterology, First Affiliated Hospital of Anhui Medical University, Hefei, China.
Key Laboratory of Digestive Diseases of Anhui Province, Hefei, China.
Inflamm Bowel Dis. 2023 Jan 5;29(1):103-115. doi: 10.1093/ibd/izac152.
Crohn's disease (CD) is an incurable chronic intestinal inflammatory disease with no recognized cause. It has been reported that the mechanosensitive ion channel PIEZO1 initiates proinflammatory responses. However, little is known about the role of PIEZO1 in CD.
Ileum biopsies were obtained from 30 patients with CD and 15 healthy volunteers. Clinical data were collected to determine the relationship between CD and PIEZO1. First, HT29 cells were incubated with Yoda1 and GsMTx4 (Grammostola spatulata mechanotoxin 4) to activate and inhibit PIEZO1, respectively. Second, PIEZO1 knockdown was performed using small interfering RNA. Third, calcium imaging, flow cytometry, and immunofluorescence were used to detect intracellular calcium and mitochondrial function. Last, real-time quantitative polymerase chain reaction, immunoblotting, and enzyme-linked immunosorbent assay were used to quantify PIEZO1, proinflammatory cytokines, and NLRP3 (NOD-like receptor 3)-related compounds.
PIEZO1 was highly expressed in the ileum of patients with CD and correlated positively with the Crohn's Disease Activity Index, platelet count, and hematocrit and fecal calprotectin levels. In HT29 cells, Yoda1 triggered calcium influx, which was inhibited by GsMTx4 treatment and small interfering RNA-mediated PIEZO1 knockdown. Increased calcium concentrations resulted in increased reactive oxygen species accumulation and decreased mitochondrial membrane potential, whereas decreased calcium concentrations caused by GsMTx4 and PIEZO1 knockdown had the opposite effect. Mechanistically, molecules in the NLRP3 pathway were activated in patients with CD and HT29 cells were stimulated by lipopolysaccharide; these effects were reversed by the knockdown of PIEZO1. Finally, PIEZO1 and NLRP3 knockdown decreased proinflammatory cytokine levels in HT29 cells.
PIEZO1 in intestinal epithelial cells caused calcium influx, which resulted in mitochondrial dysfunction and activated the NLRP3 inflammasome, mediating intestinal inflammation.
克罗恩病（CD）是一种无法治愈的慢性肠道炎症性疾病，病因不明。据报道，机械敏感离子通道PIEZO1可引发促炎反应。然而，关于PIEZO1在CD中的作用知之甚少。
从30例CD患者和15名健康志愿者中获取回肠活检组织。收集临床数据以确定CD与PIEZO1之间的关系。首先，将HT29细胞分别与Yoda1和GsMTx4（Grammostola spatulata机械毒素4）孵育，以分别激活和抑制PIEZO1。其次，使用小干扰RNA进行PIEZO1基因敲低。第三，采用钙成像、流式细胞术和免疫荧光检测细胞内钙和线粒体功能。最后，使用实时定量聚合酶链反应、免疫印迹和酶联免疫吸附测定来定量PIEZO1、促炎细胞因子和NLRP3（核苷酸结合寡聚化结构域样受体3）相关化合物。
PIEZO1在CD患者的回肠中高表达，且与克罗恩病活动指数、血小板计数、血细胞比容和粪便钙卫蛋白水平呈正相关。在HT29细胞中，Yoda1引发钙内流，而GsMTx4处理和小干扰RNA介导的PIEZO1基因敲低可抑制钙内流。钙浓度升高导致活性氧积累增加和线粒体膜电位降低，而GsMTx4和PIEZO1基因敲低引起的钙浓度降低则产生相反的效果。机制上，CD患者的NLRP3途径分子被激活，HT29细胞受到脂多糖刺激；PIEZO1基因敲低可逆转这些效应。最后，PIEZO1和NLRP3基因敲低降低了HT29细胞中的促炎细胞因子水平。
肠道上皮细胞中的PIEZO1引起钙内流，导致线粒体功能障碍并激活NLRP3炎性小体，介导肠道炎症。
