CELL-AUTONOMOUS HEDGEHOG SIGNALING CONTROLS TH17 DIFFERENTIATION TO DRIVE INTESTINAL INFLAMMATION AND IS A DRUGGABLE TARGET FOR THE TREATMENT OF INFLAMMATORY BOWEL DISEASE
CELL-AUTONOMOUS HEDGEHOG SIGNALING CONTROLS TH17 DIFFERENTIATION TO DRIVE INTESTINAL INFLAMMATION AND IS A DRUGGABLE TARGET FOR THE TREATMENT OF INFLAMMATORY BOWEL DISEASE
复制标题
细胞自主 HEDGEHOG 信号传导控制 TH17 分化以驱动肠道炎症，是治疗炎症性肠病的药物靶标
DOI：
10.1093/ibd/izac015.004
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发表时间：
2022
影响因子：
4.9
通讯作者：
Hanna J
中科院分区：
文献类型：
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作者：
Hanna J
背景：粘膜修复是IBD药物治疗的目标。前瞻性队列儿科研究表明，抑制线粒体基因会导致溃疡性结肠炎（UC）和克罗恩病（CD）的不利临床结果。我们假设上皮线粒体呼吸恢复的无能损害了IBD溃疡愈合。在目前的研究中，我们测试了一种改善线粒体功能的新化合物（AuPhos）是否能促进IBD溃疡愈合。方法C57/BL/6 （WT）小鼠单次口服（25mg/kg） AuPhos后（6h、12h、24h）进行生物分布和药代动力学（PK）研究。采用石墨炉原子吸收光谱法测定正常结落细胞（NCM460）中的金含量，测定线粒体对AuPhos的摄取。采用高分辨率呼吸仪检测auphos喂养的WT小鼠离体隐窝iecs的耗氧量（OCR）。在DSS (2%; 7d) WT （B6）小鼠中检测了AuPhos对结肠炎的作用。在21d的时间过程中，测定疾病活动指数（DAI）（体重减轻、腹泻和便血）、肠通透性（fitc -葡聚糖）、组织学评分和隐窝裂变频率。采用RT-qPCR检测组织中线粒体酶、细胞因子、趋化因子和肠干细胞（ISC）标记基因的mRNA水平。结果生物分布和PK研究表明，口服AuPhos在小肠和结肠组织中含量较高，全身吸收有限。AuPhos在IEC中表现出剂量依赖的线粒体摄取，在体内口服给药后，呼吸测量显示OCR增加了约30%。AuPhos治疗降低DSS结肠炎小鼠DAI （**; p<0.01）、结肠炎组织学评分D11-15 （*; p<0.05）和fitc -葡聚糖通透性。值得注意的是，AuPhos增加了dss -结肠炎小鼠愈合溃疡附近的裂变隐窝数量（**;p<0.01），同时降低了促炎细胞因子/趋化因子（IL-1β、IL-6、IFN-γ、IP10）的mRNA表达。AuPhos诱导ISC标记物[Lgr4 （*; p<0.05）、Lgr5、Lrig1 (***; p<0.001)]和线粒体复合物[mtCO1 （**; p<0.01）和COX2 (***; p<0.001)]的mRNA表达。这些发现表明，auphos诱导的线粒体呼吸驱动参与结肠炎溃疡愈合的IEC基因的转录组调控。结论AuPhos化合物通过增加粘膜OxPHOS代谢促进急性结肠炎溃疡愈合。具体来说，我们发现AuPhos增加了线粒体呼吸诱导的隐窝裂变和溃疡愈合，这与减少粘膜炎症和增加屏障完整性有关。总之，AuPhos可能是一种重要的“一流”口服治疗药物，用于纠正IBD发病机制的核心代谢功能障碍。
BACKGROUNDMucosal repair is the goal of medical therapy in IBD. Prospective inception cohort pediatric studies suggest that suppression of mitochondrial genes lead to unfavorable clinical outcomes in ulcerative colitis (UC) and Crohn’s disease (CD). We posit that the inability to restore epithelial mitochondrial respiration impairs ulcer healing in IBD. In the current study, we tested whether a novel compound (AuPhos) that improves mitochondrial function promotes ulcer healing in IBD.METHODSBiodistribution and pharmacokinectic (PK) studies were performed (6h, 12h, 24h) after single oral dose (25mg/kg) of AuPhos using C57/BL/6 (WT) mice. Mitochondrial uptake of AuPhos was determined by measuring gold content in normal colonocytes (NCM460) using graphite furnace atomic absorption spectroscopy. Oxygen consumption rate (OCR) in isolated crypt-IECs from AuPhos-fed WT mice were examined using high-resolution respirometry. The effect of AuPhos in colitis was tested in DSS (2%; 7d) WT (B6) mice. Disease activity index (DAI) (weight loss, diarrhea, and hematochezia), intestinal permeability (FITC-dextran), histological scoring and the frequency of fissioning crypts were determined throughout the 21d time course. Tissue mRNA levels for mitochondrial enzyme, cytokine, chemokine and intestinal stem cell (ISC) marker genes were assessed by RT-qPCR.RESULTSBiodistribution and PK studies revealed that higher levels of orally administered AuPhos in small intestine and colon tissue, with limited systemic absorption. AuPhos displayed a dose-dependent mitochondrial uptake in IEC where respirometry showed >30% increase in OCR after oral dosing in vivo. AuPhos treatment decreased DAI (**; p<0.01), histologic colitis scores D11-15 (*; p<0.05) and FITC-dextran permeability in DSS colitis mice. Notably, AuPhos increased fissioning crypt numbers near healing ulcers in DSS-colitis mice (**; p<0.01) while it reduced mRNA for pro-inflammatory cytokines/chemokines (IL-1β, IL-6, IFN-γ, IP10). AuPhos induced mRNA for ISC markers [Lgr4 (*; p<0.05), Lgr5, Lrig1 (***; p<0.001)] and mitochondrial complexes [mtCO1 (**; p<0.01) and COX2 (***; p<0.001)]. These findings suggest that AuPhos-induced mitochondrial respiration drives transcriptomic regulation of IEC genes involved in colitis ulcer healing.CONCLUSIONOur data suggests that AuPhos compound improves ulcer healing under acute colitis conditions by increasing mucosal OxPHOS metabolism. Specifically, we find that AuPhos increases mitochondrial respiration-induced crypt fissioning and ulcer healing associated with reduced mucosal inflammation and increased barrier integrity. Overall, AuPhos may be an important “first-in class” oral therapeutic for correcting the metabolic dysfunction central to IBD pathogenesis.