A1AR保护糖尿病肾小管周微环境的非管球反馈机制

糖尿病肾病（DN）是ESRD的重要原因，目前还没有有效的方法遏制其进展，因此探讨DN发病机制,寻找新的干预位点有重要的现实意义。而肾小管周毛细血管（PTC）损伤被认为是DN和非DN进展的共同途径和预测肾脏结局的独立危险因素。本研究在DN患者、已经建立的腺苷1型受体（A1AR）基因敲除的1型和2型DM（Akita,db/db）小鼠模型和体外实验中，从分子、细胞、组织和器官水平,①观察A1AR缺失对DN肾小管周微环境（肾小管、间质和肾小管周毛细血管）非依赖于管球反馈的损伤，与GFR和蛋白尿的关系; ②观察A1AR与Adora2b受体的协同作用；③确定DN，A1AR活化在上调Treg细胞抑制活性、保护刷状缘转运蛋白Megalin与细胞间紧密连接的稳定性3方面的核心地位，观察A1AR下游Rho/Rho 激酶及NF-kB活化的调节机制，进而为DN防治提供新的思路和潜在的干预位点。

Diabetic nephropathy(DN) is the leading cause of End Stage Renal Disease(ESRD). But there is still no effective interventions to slow the progression of diabetes-induced CKD. Therefore, studies to identify novel therapeutic interventions to prevent DN or slow its progression are urgently needed. It has been reasonable to infer that peritubular capillary (PTC) failure is common pathway and an independent risk factor of kidney survival in both non-diabetic and DN. In the present study, we try to investigate the functional roles of A1AR during renal peritubular microenvironment protection of DN, by combining genetic and pharmacologic approaches.First in DN patients and A1AR-/-Akita Diabetes mice and A1AR-/-db/db mice , the relationship between renal peritubular microenvironment ( RPM, including tubular, interstitial and PTC,) injury and the proteuria or GFR will be evaluated.Then the Adora2b receptor antagonist will be used to observe the co-operation of A1AR. To identify the core of extracellular adenosine generation and signaling through tubular-expressed A1AR in RPM protection, the megalin, cubilin mediated endocytosis, Treg cells infiltration and tight junction changes will be studied in vivo and vitro. Rho/Rho kinase pathway and activation of NF-kB will be studied by antagonist and agonist in vitro cultured tubular cells with high glucose. claudin-1 target siRNA will be used to identify the cooperation of transmembrane protein and scaffolding protein in tubular tight junction.Take together, the present study would like to indentify the protect effect and mechanism of A1AR independent Tubulo-glomerular feedback pathway, implicate a new idea of DN theraphy.