上皮来源miR-586介导巨噬细胞IDO相关代谢激活及M1极化参与结晶肾损伤的机制研究

泌尿系结石的关键病理基础为草酸钙结晶诱导的巨噬细胞相关的小管间质炎症，但是其中巨噬细胞炎性活化与结晶刺激小管上皮细胞损伤之间的关联及细胞间通讯机制并不清楚。前期研究发现1.色氨酸代谢关键酶IDO及其产物KYN诱导的抗炎作用对于小鼠结晶肾损伤组织中的巨噬细胞M1极化具有重要意义；2.高通量筛选发现结晶刺激后上皮来源外泌体高表达miR-586；3.miR-586可抑制巨噬细胞IDO的表达。为此，课题组提出假说：结晶肾损伤中，上皮细胞在结晶刺激下miR-586表达上调，通过外泌体转运作用于巨噬细胞，促进其IDO表达下调，KYN-AhR-TSG-6通路受到抑制，巨噬细胞M1极化，小管间质损伤加重。本项目拟运用体内外模型，证实：结晶刺激上皮细胞miR-586转录活化的分子机制，外泌体miR-586在上皮-巨噬细胞间通讯中的作用，IDO促进巨噬细胞活化的具体通路，从而为防治结晶肾损伤提供新的理论参考。

The key pathological basis of urolithiasis is macrophage related tubulointerstitial inflammation induced by calcium oxalate crystals, but it’s still unclear about the relationship between inflammatory activation of macrophages and crystal-induced tubule epithelial cells injury couple with the intercellular communication mechanism. Previous studies of us found that: 1. the anti-inflammatory effect induced by the tryptophan metabolic enzyme IDO and its product KYN is of great significance to the polarization of M1 macrophages in kidney tissue in mice with crystal kidney injury; 2. high-throughput screens found that tubule-derived exosomes highly expressed miR-586 after crystal stimulation; 3. miR-586 could suppress IDO expression in macrophages. To this end, we proposed the hypothesis: crystal induces the upregulation of miR-586 in epithelial cells, and then miR-586 is transported to macrophages by exosomes, promoting the downregulation of macrophage IDO expression, resulting in the inhibition of KYN-AhR-TSG-6 pathway, causing M1 polarization of macrophages, eventually increasing tubulointerstitial damage. This study intends to use in vivo and in vitro models to confirm the molecular mechanism of crystal-induced transcriptional activation of miR-586 in epithelial cells, the role of exosome miR-586 in epithelial-macrophage communication, and the specific pathway by which IDO promotes macrophage activation, which may provide a new theoretical reference for the prevention and treatment of crystal-induced kidney injury.