Spironolactone promotes autophagy via inhibiting PI3K/AKT/mTOR signalling pathway and reduce adhesive capacity damage in podocytes under mechanical stress.
Spironolactone promotes autophagy via inhibiting PI3K/AKT/mTOR signalling pathway and reduce adhesive capacity damage in podocytes under mechanical stress.
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DOI：
10.1042/bsr20160086
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发表时间：
2016-08
影响因子：
4
通讯作者：
Yan T
中科院分区：
文献类型：
--
作者：
Li D;Lu Z;Xu Z;Ji J;Zheng Z;Lin S;Yan T
机械应力会对足细胞产生有害的粘附作用，被认为是糖尿病肾病（DN）早期进展的主要原因。我们以前的研究表明螺内酯可以改善糖尿病大鼠足细胞粘附能力。据报道，自噬对肾损伤具有保护作用。本研究探讨了机械应力下螺内酯降低足细胞粘附能力损伤的潜在机制，重点关注自噬的参与。将暴露于机械应力的人条件永生化足细胞用螺内酯、LY 294002或雷帕霉素处理48小时。通过免疫荧光染色检测LC 3斑点的积累。Western blotting检测足细胞盐皮质激素受体（MR）、整合素β1、LC 3、Atg 5、p85-PI 3 K、p-Akt、p-mTOR的表达。还用分光光度法进行足细胞与IV型胶原的粘附。免疫荧光染色显示，机械应力下足细胞自噬水平降低。在机械应力下，足细胞中还检测到整合素β1、LC 3、Atg 5的减少和PI 3 K/Akt/mTOR通路的异常激活。螺内酯上调整合素β1、LC 3、Atg 5的表达，下调p85-PI 3 K、p-Akt、p-mTOR的表达，减轻足细胞粘附能力的损伤。我们的数据表明螺内酯通过阻断PI 3 K/Akt/mTOR通路和恢复自噬活性来抑制机械应激诱导的足细胞粘附能力损伤。
Mechanical stress which would cause deleterious adhesive effects on podocytes is considered a major contributor to the early progress of diabetic nephropathy (DN). Our previous study has shown that spironolactone could ameliorate podocytic adhesive capacity in diabetic rats. Autophagy has been reported to have a protective role against renal injury. The present study investigated the underlying mechanisms by which spironolactone reduced adhesive capacity damage in podocytes under mechanical stress, focusing on the involvement of autophagy. Human conditional immortalized podocytes exposed to mechanical stress were treated with spironolactone, LY294002 or rapamycin for 48 h. The accumulation of LC3 puncta was detected by immunofluorescence staining. Podocyte expression of mineralocorticoid receptor (MR), integrin β1, LC3, Atg5, p85-PI3K, p-Akt, p-mTOR were detected by Western blotting. Podocyte adhesion to collagen type IV was also performed with spectrophotometry. Immunofluorescence staining showed that the normal level of autophagy was reduced in podocytes under mechanical stress. Decreased integrin β1, LC3, Atg5 and abnormal activation of the PI3K/Akt/mTOR pathway were also detected in podocytes under mechanical stress. Spironolactone up-regulated integrin β1, LC3, Atg5 expression, down-regulated p85-PI3K, p-Akt, p-mTOR expression and reduced podocytic adhesive capacity damage. Our data demonstrated that spironolactone inhibited mechanical-stress-induced podocytic adhesive capacity damage through blocking PI3K/Akt/mTOR pathway and restoring autophagy activity.