Total flavonoids from Smilax glabra Roxb blocks epithelial-mesenchymal transition and inhibits renal interstitial fibrosis by targeting miR-21/PTEN signaling
Total flavonoids from Smilax glabra Roxb blocks epithelial-mesenchymal transition and inhibits renal interstitial fibrosis by targeting miR-21/PTEN signaling
复制标题
土茯苓总黄酮通过靶向miR-21/PTEN信号通路阻断上皮-间充质转化并抑制肾间质纤维化
DOI：
10.1002/jcb.27668
复制
发表时间：
2019-03-01
影响因子：
4
通讯作者：
Cai, Yueqin
中科院分区：
文献类型：
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作者：
Luo, Qihan;Cai, Zhaowei;Cai, Yueqin
研究背景土茯苓是一种传统的中草药，在民间有着广泛的应用。本研究旨在探讨S.土茯苓提取物、土茯苓纯总黄酮（PTFS）对肾间质纤维化（RIF）的影响及其机制。方法首先建立大鼠单侧输尿管梗阻手术模型，诱导RIF。然后将大鼠分组，用不同浓度的PTFS处理。其次，通过添加转化生长因子-β 1（TGF-β 1），HK-2细胞经历上皮-间充质转化（EMT）。此外，诱导EMT后的HK-2细胞用microRNA-21（miR-21）模拟物或抑制剂转染。将这些HK-2细胞分组并用不同浓度的PTFS处理。最后，采用实时荧光定量PCR和Western blot方法检测PTFS作用后肾组织和HK-2细胞中可能参与RIF的信号因子的表达。结果体内外实验表明，PTFS可在mRNA和蛋白水平上降低间充质标志物α-平滑肌肌动蛋白（α-SMA）的表达，增加上皮标志物E-cadherin的表达。此外，PTFS还减弱了经历EMT的肾组织和HK-2细胞中TGF-β 1/Smad信号的表达。在HK-2细胞中，miR-21的过表达或抑制可通过靶向磷酸酶和张力同源物（PTEN）激活或阻断PI 3 K/Akt信号通路，进而通过调节α-SMA和E-cadherin的表达促进或抑制TGF-β 1诱导的EMT进程。此外，PTFS处理通过阻断miR-21/PTEN/PI 3 K/Akt信号传导抑制TGF-β 1诱导的EMT进展。结论PTFS在体内外均具有较强的抗EMT和抗纤维化作用。这些作用的潜在机制可能与抑制TGF-β 1/Smad及其下游miR-21/PTEN信号传导有关，从而导致RIF期间EMT过程的阻断。
Background Smilax glabra Roxb, a traditional Chinese herb, has been widely used in folk medicine. The current study was performed to investigate the protective effect of S. glabra Roxb extract, pure total flavonoids from Smilax glabra Roxb (PTFS), on renal interstitial fibrosis (RIF) and its underlying mechanism. Methods First, a surgical model of unilateral ureteral obstruction was established in rats to induce RIF. Then, rats were grouped and treated with PTFS at different concentration. Second, HK-2 cells underwent an epithelial-mesenchymal transition (EMT) by the addition of transforming growth factor-beta 1 (TGF-beta 1). Additionally, HK-2 cells after inducing for EMT were transfected with microRNA-21 (miR-21) mimic or inhibitor. These HK-2 cells were grouped and treated with PTFS at different concentration. Finally, real-time polymerase chain reaction and Western blot analysis were performed to detect the expression of possible signaling factor involved in RIF in renal tissues or HK-2 cells after PTFS treatment. Results In vivo and in vitro experiments indicated that PTFS treatment could decrease the expression of alpha-smooth muscle actin (alpha-SMA; mesenchymal marker) and increase the expression of E-cadherin (epithelial marker) in both messenger RNA and protein level. Moreover, PTFS also attenuated the expression of TGF-beta 1/Smad signaling in both renal tissues and HK-2 cells that underwent EMT. Overexpression or inhibition of miR-21 in HK-2 cells activated or blocked the PI3K/Akt signaling via targeting phosphatase and tension homolog (PTEN), and then promoted or suppressed the progress of TGF-beta 1-induced EMT by regulating the expression of alpha-SMA and E-cadherin. Furthermore, PTFS treatment inhibited TGF-beta 1-induced EMT progress by blocking miR-21/PTEN/PI3K/Akt signaling. Conclusion PTFS has strong anti-EMT and antifibrosis effects both in vitro and in vivo. The mechanism underlying these effects may be related to inhibition of TGF-beta 1/Smad, and their downstream miR-21/PTEN signaling, leading to blocks of EMT process during RIF.