Abstract：
Diabetic nephropathy (DN) threatens the survival quality of patients, with complex pathogenesis. Circular RNA (circRNA) dysregulation occurs in DN development. This work aimed to investigate the role of circ-Luc7l in DN cell models and related molecular mechanisms. The expression of circ-Luc7l, microRNA (miR)-205-5p, and transforming growth factor-beta receptor 1 (Tgfbr1) was examined by real-time quantitative PCR (RT-qPCR). Cell viability and proliferation were detected by Cell Counting Kit-8 (CCK-8) assay and EdU assay. The expression of extracellular matrix (ECM)-related markers and Tgrbr1 protein was measured by Western blot. The binding between miR-205-5p and circ-Luc7l or Tgfbr1 was validated by dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay, or RNA pull-down assay. Experimental animal models were established to elucidate the function of circ-Luc7l in vivo. Circ-Luc7l expression was notably enhanced in high glucose (HG)-treated mesangial cells. Knockdown of circ-Luc7l attenuated HG-induced cell proliferation, inflammation, and ECM accumulation in vitro and relieved inflammation and ECM accumulation of kidneys of diabetic mice in vivo. Circ-Luc7l targeted miR-205-5p, and miR-205-5p inhibition rescued the depletion effects of circ-Luc7l knockdown on cell proliferation, inflammation, and ECM accumulation. MiR-205-5p bound to Tgfbr1 whose expression was negatively regulated by circ-Luc7l. Tgfbr1 overexpression also rescued the depletion effects of circ-Luc7l knockdown on cell proliferation, inflammation, and ECM accumulation. In HG conditions, increased circ-Luc7l upregulated Tgfbr1 expression via targeting miR-205-5p to induce DN progression.
摘要：
糖尿病肾病(DN)威胁着患者的生存质量,具有复杂的发病机制。环状RNA(circularRNA,circRNA)失调发生在DN发育中。本研究旨在探讨circ-Luc7l在DN细胞模型中的作用及相关分子机制。circ-Luc7l的表达，microRNA(miR)-205-5p,通过实时定量PCR（RT-qPCR）检测转化生长因子β受体1（Tgfbr1）。通过细胞计数试剂盒-8(CCK-8)测定和EdU测定检测细胞活力和增殖。Westernblot检测细胞外基质（ECM）相关标志物和Tgrbr1蛋白的表达。miR-205-5p与circ-Luc7l或Tgfbrl之间的结合通过双荧光素酶报告基因测定来验证,RNA免疫沉淀（RIP）测定，或RNA下拉测定。建立实验动物模型以阐明circ-Luc7l在体内的功能。Circ-Luc7l表达在高葡萄糖(HG)处理的肾小球系膜细胞中显著增强。敲除circ-Luc7l减弱HG诱导的细胞增殖，炎症,并在体内减轻糖尿病小鼠肾脏的炎症和ECM积累。Circ-Luc7l靶向miR-205-5p,和miR-205-5p抑制拯救了circ-Luc7l敲低对细胞增殖的耗尽效应，炎症,和ECM积累。MiR-205-5p与Tgfbr1结合,其表达被circ-Luc7l负调控。Tgfbr1过表达还挽救了circ-Luc7l敲低对细胞增殖的耗竭作用，炎症,和ECM积累。在HG条件下，增加的circ-Luc7l通过靶向miR-205-5p上调Tgfbrl表达以诱导DN进展。
