Chen Tingfang, Zheng Li Yang, Xiao Wenzhen, Gui Dingkun, Wang Xiaoxia, Wang Niansong
Department of Medicine, Soochow University, Suzhou, PR China.
Cell Physiol Biochem. 2015;35(4):1425-36. doi: 10.1159/000373963. Epub 2015 Mar 12.
Epithelial-to-mesenchymal transition (EMT) is a potential pathway leading to podocyte depletion and proteinuria in diabetic kidney disease (DKD). Here, we investigated the protective effects of Emodin (EMO) on high glucose (HG) induced-podocyte EMT in-vitro and in-vivo.
Conditionally immortalized mouse podocytes were exposed to HG with 30 μg /ml of EMO and 1 μmol/ml of integrin-linked kinase (ILK) inhibitor QLT0267 for 24 h. Streptozotocin (STZ)-induced diabetic rats were treated with EMO at 20 mg· kg(-1)· d(-1) and QLT0267 at 10 mg· kg(-1)· w(-1) p.o., for 12 weeks. Albuminuria and blood glucose level were measured. Immunohistochemistry, immunofluorescence, western blotting and real-time PCR were used to detect expression of ILK, the epithelial marker of nephrin and the mesenchymal marker of desmin in-vitro and in-vivo.
HG increased podocyte ILK and desmin expression while decreased nephrin expression. However, EMO significantly inhibited ILK and desmin expression and partially restored nephrin expression in HG-stimulated podocytes. These in-vitro observations were further confirmed in-vivo. Treatment with EMO for 12 weeks attenuated albuminuria, renal histopathology and podocyte foot process effacement in diabetic rats. EMO also repressed renal ILK and desmin expression, preserved nephrin expression, as well as ameliorated albuminuria in STZ-induced diabetic rats.
EMO ameliorated glucose-induced EMT and subsequent podocyte dysfunction partly through ILK and desmin inhibition as well as nephrin upregulatiotion, which might provide a potential novel therapeutic option for DKD.
上皮-间质转化（EMT）是导致糖尿病肾病（DKD）足细胞耗竭和蛋白尿的潜在途径。在此，我们研究了大黄素（EMO）在体外和体内对高糖（HG）诱导的足细胞EMT的保护作用。
将条件永生化小鼠足细胞暴露于含有30μg/ml EMO和1μmol/ml整合素连接激酶（ILK）抑制剂QLT0267的HG中24小时。链脲佐菌素（STZ）诱导的糖尿病大鼠口服给予20mg·kg⁻¹·d⁻¹的EMO和10mg·kg⁻¹·w⁻¹的QLT0267，持续12周。测量蛋白尿和血糖水平。采用免疫组织化学、免疫荧光、蛋白质印迹和实时PCR检测体外和体内ILK、足细胞上皮标志物nephrin和间充质标志物desmin的表达。
HG增加了足细胞ILK和desmin的表达，同时降低了nephrin的表达。然而，EMO显著抑制了HG刺激的足细胞中ILK和desmin的表达，并部分恢复了nephrin的表达。这些体外观察结果在体内得到了进一步证实。用EMO治疗12周可减轻糖尿病大鼠的蛋白尿、肾脏组织病理学改变和足细胞足突消失。EMO还抑制了糖尿病大鼠肾脏中ILK和desmin的表达，保留了nephrin的表达，并改善了蛋白尿。
EMO部分通过抑制ILK和desmin以及上调nephrin改善了葡萄糖诱导的EMT和随后的足细胞功能障碍，这可能为DKD提供一种潜在的新治疗选择。
