基于KDM3A-SP1去甲基化调控探索肾康丸干预糖尿病肾脏疾病肾小管间质纤维化的机制和物质基础

肾小管间质纤维化（TIF）是糖尿病肾脏疾病（DKD）进展的重要机制。我们前期研究已证实，肾康丸能有效降低肾小管纤维化因子的表达并改善TIF，但具体机制尚不清楚。进一步研究发现，去甲基化酶KDM3A在DKD小鼠肾小管高表达，在HK2细胞中过表达KDM3A，可激活TGFβ1等纤维化因子，共转染SP1能显著增强KDM3A该调控作用。而肾康丸可显著降低DKD小鼠KDM3A、SP1、TGFβ1的表达，进一步对肾康丸有效成分与靶点分析，发现槲皮素等8个有效成分能与KDM3A靶向结合。据此我们提出假说：肾康丸可通过下调KDM3A-SP1表达，抑制其对TGFβ1的去甲基化作用进而改善TIF，槲皮素等8个有效成分可能是肾康丸抗TIF的物质基础。本项目拟用基因敲除小鼠模型及细胞模型，探讨KDM3A/SP1介导去甲基化调控在TIF中的作用以及肾康丸对此过程的影响，并探索其作用的物质基础，为其临床应用提供依据。

Tubulointerstitial fibrosis (TIF) plays a significant role in the progressions of Diabetic Kidney Disease (DKD). Our previous studies found that Shenkang Pills can effectively decrease the expression of renal tubular fibrosis factor and reduce TIF, but the specific mechanism is not clear. Further studies revealed that demethylase KDM3A was highly expressed in renal tubules of DKD mice, overexpression of KDM3A in HK2 cells can activate fibrosis factors such as TGFβ1 via demethylation, and co-transfection with sp1 can significantly enhance the regulatory effect. Shenkang Pills can also dramatically reduce the expression of KDM3A, SP1, TGFβ1 in DKD mice. Further analysis of the active components and target sites of Shenkang Pills showed that eight candidate compounds such as quercetin can bind to KDM3A. Therefore, from the results of this analysis we can suggest that Shenkang Pills could down-regulate the expression of KDM3A/SP1, inhibit the demethylation of TGFβ1 and reduce TIF. Besides, those eight active ingredients including quercetin might be the anti-TIF chemical basis of Shenkang Pills. In this study, KDM3A-knockout mouse model and gene silencing cell model were used to explore the role of KDM3A/SP1-mediated demethylation regulation in TIF and the effect of Shenkang Pills on this process, and explore the chemical basis of Shenkang Pills. This research will provide evidences for clinical application of Shenkang Pills.