The inhibition of SGK1 suppresses epithelial-mesenchymal transition and promotes renal tubular epithelial cell autophagy in diabetic nephropathy.
The inhibition of SGK1 suppresses epithelial-mesenchymal transition and promotes renal tubular epithelial cell autophagy in diabetic nephropathy.
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发表时间：
2019-08
影响因子：
2.2
通讯作者：
Langen Zhuang;Guoxi Jin;Xiaolei Hu;Qingqing Yang;Zhaoming Shi
中科院分区：
文献类型：
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作者：
Langen Zhuang;Guoxi Jin;Xiaolei Hu;Qingqing Yang;Zhaoming Shi
糖尿病肾病是糖尿病的常见并发症，是终末期肾病的主要原因。然而，糖尿病肾病的发病机制尚不清楚。血清和糖皮质激素诱导的蛋白激酶(SGK)1是一种普遍表达的蛋白激酶，本研究在体内和体外研究了其对糖尿病肾病的影响。实验选用雄性BALB/C小鼠和人肾小管上皮细胞系HK-2。实验选用雄性BALB/C小鼠和人肾小管上皮细胞系HK-2。HE染色观察病理改变，免疫组织化学方法检测SGK-1的表达。应用SGK1抑制剂GSK650394分析SGK1在HK-2细胞上皮-间充质转化(EMT)中的作用。用免疫印迹法检测相关蛋白的表达。此外，使用划痕伤口愈合试验测量移动性。用自噬抑制剂3-甲基腺嘌呤(3-MA)检测SGK1抑制后自噬的变化。对自噬蛋白的表达进行分析。检测PI3K、AKT、mTOR的表达及其磷酸化水平。结果表明，肾组织超微结构受损，SGK1表达明显增加。SGK1抑制后，HK-2细胞EMT受到抑制，细胞迁移减弱。此外，还促进了HK-2细胞的自噬，Beclin-1和Lc3 II的表达增加，而p62的表达降低。此外，PI3K、AKT和mTOR的磷酸化水平明显上调。结果表明，通过3-MA阻断自噬信号可抑制SGK1对HG诱导的细胞损伤的保护作用。我们的研究表明，SGK1抑制促进了糖尿病肾病的自噬，并抑制了肾小管上皮细胞的EMT，提示SGK1可能是糖尿病肾病的一个潜在的治疗靶点。
Diabetic nephropathy (DN) is a common complication of diabetes that is the dominant cause of end-stage renal disease. However, the pathological mechanism of DN is yet to be elucidated. Serum and glucocorticoid induced kinase (SGK) 1, a ubiquitously expressed kinase, was employed in the current study to assess its effect on DN in vivo and in vitro. Male BALB/C mice and a human tubular epithelial cell line (HK-2) were utilized for experimentation. Male BALB/C mice and a human tubular epithelial cell line (HK-2) were utilized for experimentation. Pathological changes were measured via HE and staining and immunohistochemistry was performed to measure the expression of SGK 1. An SGK1 inhibitor, GSK650394, was applied to analyze the role of SGK1 in HK-2 cell epithelial-mesenchymal transition (EMT). Associated protein expressions were assessed via western blotting. In addition, migration was measured using a scratch wound healing assay. 3-methyladenine (3-MA), an autophagy inhibitor, was used to determine the variation of autophagy following SGK1 inhibition. The expression of autophagy proteins were analyzed. Furthermore, the expression of PI3K, AKT, mTOR and their levels of phosphorylation were measured. The results revealed that the ultrastructure of renal tissue suffered damage and that the expression of SGK1 was markedly increased. After SGK1 inhibition, HK-2 cell EMT was suppressed and cell migration was attenuated. Furthermore, the autophagy of HK-2 cells was promoted, an increased expression of Beclin-1 and LC3 II was detected, and a decreased expression of p62 was observed. Additionally, the phosphorylation of PI3K, AKT and mTOR were markedly upregulated. The results indicated that blocking autophagy signaling via 3-MA muted SGK1-protected against HG-evoked cell injury. Our study demonstrated that SGK1 inhibition promoted autophagy and suppressed renal tubular epithelial cell EMT in DN, indicating that SGK1 may serve as a potential therapeutic target of DN.