LncRNA HOTAIR promotes renal interstitial fibrosis by regulating Notch1 pathway via the modulation of miR-124.

To understand the mechanism of long non-coding RNA (LncRNA) HOTAIR on renal interstitial fibrosis (RIF) by regulating Notch1 pathway via the modulation of miR-124. Unilateral ureteral occlusion (UUO) was used to construct the RIF rat model. HK-2 cells induced by TGF-β1 were used for the in vitro experiment, which were divided into five groups: Vehicle, TGF-β1, si-HOTAIR+TGF-β1, miR-124 inhibitor+TGF-β1, and si-HOTAIR+miR-124 inhibitor+TGF-β1 groups. Quantitative real-time PCR (qRT-PCR) and Western blot were performed to detect the expression of HOTAIR, miR-124, Notch1- and epithelial-to-mesenchymal transition (EMT)-related proteins. Significant elevated HOTAIR and reduced miR-124 were presented in UUO rats and TGF-β1-induced HK-2 cells in a time-dependent manner, with the increased Jagged1 (JAG1), Notch1, NICD, α-SMA and FN, as well as the decreased E-cadherin (all P < 0.05). Compared with the TGF-β1 group, cells in the si-HOTAIR+TGF-β1 group were remarkably declined in cell proliferation and the protein expressions of JAG1, Notch1, NICD, α-SMA, and FN, but dramatically higher in E-cadherin expression (all P < 0.05). However, in comparison with the si-HOTAIR+TGF-β1 group, cells in the si-HOTAIR+miR-124 inhibitor+TGF-β1 group were apparently improved in proliferation and the protein expression of JAG1, Notch1, NICD, α-SMA, and FN, but substantially reduced in the level of E-cadherin protein (all P < 0.05). Silencing lncRNA HOTAIR can up-regulate miR-124 to block Notch1 pathway, and thereby alleviating EMT and RIF, indicating HOTAIR as a potential target for RIF treatment.

Zhou H ，Gao L ，Yu ZH ，Hong SJ ，Zhang ZW ，Qiu ZZ ... -  《-》

Paeonol reverses promoting effect of the HOTAIR/miR-124/Notch1 axis on renal interstitial fibrosis in a rat model.

Renal interstitial fibrosis (RIF) is a common manifestation of inflammatory and noninflammatory renal diseases, which correlates to renal excretory dysfunction. Recently, the long noncoding RNAs (lncRNAs) have been demonstrated to be involved in the development of various renal diseases. Here, we aim to determine whether paeonol (PAE) affects RIF with involvement of the lncRNA HOX transcript antisense intergenic RNA (HOTAIR)/microRNA-124 (miR-124)/Notch1 axis. RIF rat models were established by performing unilateral ureteral occlusion (UUO), in which interactions between HOTAIR, Notch1, and miR-124 were determined. To identify the roles of PAE and HOTAIR in RIF, rats were injected with HOTAIR or PAE. Subsequently, to further investigate the underlying mechanism of PAE in RIF, epithelial to mesenchymal transition (EMT)- and migration-related genes in NRK-49F cells were measured. Next, rats were further treated with IMR-1 (inhibitor of the Notch1/Jagged1 signaling pathway) to determine how PAE influences the Notch1/Jagged1 signaling pathway. HOTAIR interacted with miR-124, and miR-124 directly targeted Notch1, and HOTAIR was observed to be upregulated in RIF rats. PAE was found to decrease HOTAIR and Notch1 expression but to increase the miR-124 expression in RIF rats. PAE inhibited EMT and migration of NRK-49F cells facilitated by HOTAIR. HOTAIR activated the Notch1/Jagged1 signaling pathway by downregulating miR-124, while PAE reversed these effects of HOTAIR on the Notch1/Jagged1 signaling pathway. Overall, our study demonstrates the contributory effect of lncRNA HOTAIR on RIF by activating the Notch1/Jagged1 signaling pathway via inhibition of miR-124, whereas administration of PAE can alleviate the effects of HOTAIR on RIF.

Zhou H ，Qiu ZZ ，Yu ZH ，Gao L ，He JM ，Zhang ZW ，Zheng J ... -  《-》

Total flavonoids from Smilax glabra Roxb blocks epithelial-mesenchymal transition and inhibits renal interstitial fibrosis by targeting miR-21/PTEN signaling.

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. 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-β1 (TGF-β1). 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. In vivo and in vitro experiments indicated that PTFS treatment could decrease the expression of α-smooth muscle actin (α-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-β1/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-β1-induced EMT by regulating the expression of α-SMA and E-cadherin. Furthermore, PTFS treatment inhibited TGF-β1-induced EMT progress by blocking miR-21/PTEN/PI3K/Akt signaling. 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-β1/Smad, and their downstream miR-21/PTEN signaling, leading to blocks of EMT process during RIF.

Luo Q ，Cai Z ，Tu J ，Ling Y ，Wang D ，Cai Y ... -  《-》

Silencing of the lncRNA TUG1 attenuates the epithelial-mesenchymal transition of renal tubular epithelial cells by sponging miR-141-3p via regulating β-catenin.

Zhang B ，Zhao C ，Hou L ，Wu Y ... -  《-》

The long noncoding RNA myocardial infarction-associated transcript modulates the epithelial-mesenchymal transition in renal interstitial fibrosis.

Renal interstitial fibrosis (RIF) is marked by the epithelial-mesenchymal transition (EMT) and excessive extracellular matrix deposition. The long noncoding RNA myocardial infarction-associated transcript (MIAT) facilitates RIF; however, the molecular mechanism of MIAT in RIF remains unclear. Here, we explored the possible underlying mechanisms through which MIAT modulates RIF. MIAT expression in human renal fibrotic tissues and unilateral ureteral obstruction (UUO) model mice was detected by qPCR. Transforming growth factor β1 (TGF-β1) was introduced to stimulate the EMT in human renal proximal tubular epithelial (HK-2) cells. CCK8, EdU, transwell and wound healing assays were employed to measure cell viability, proliferation, and migration respectively. RNA immunoprecipitation (RIP) assays and dual luciferase reporter assays were applied to determine the relationships among MIAT, miR-145, and EIF5A2. MIAT was upregulated in human renal fibrotic tissues and UUO model mice compared with normal tissue adjacent to renal tumors and sham operation mice, respectively. MIAT knockdown reduced cell viability, proliferation, migration, and the EMT in HK-2 cells. Additionally, MIAT served as an endogenous sponge for miR-145 in the TGF-β1-induced-EMT in HK-2 cells, as demonstrated by dual luciferase reporter assays and RIP assays. EIF5A2 was confirmed as a target of miR-145, and MIAT knockdown suppressed EIF5A2 expression by sponging miR-145. Downregulation of EIF5A2 partly reversed induction of the EMT by miR-145 inhibitor transfection. MIAT promoted cell viability, proliferation, migration, and the EMT via regulation of the miR-145/EIF5A2 axis. These data established a potential therapy for RIF.

Wang Z ，Zhang B ，Chen Z ，He Y ，Ru F ，Liu P ，Chen X ... -  《-》