MicroRNA-140-5p Mediates Renal Fibrosis Through TGF-β1/Smad Signaling Pathway by Directly Targeting TGFBR1

Abstract

Renal tubulointerstitial fibrosis is usually the final outcome of various end-stage renal diseases. Recent studies have reported that microRNAs (miRNAs) play an important role in renal fibrosis. However, the biological function of microRNAs in renal fibrosis is complicated and remains unclear. In this study, our results show that miR-140-5p expression is significantly down-regulated in mice with unilateral ureteral obstruction and human proximal tubule epithelial cells (HK2) treated with TGF-β1. The knockdown of miR-140-5p upregulates the expression levels of collagen I, collagen IV, and α-SMA, decreases E-cadherin expression, and increases Smad-2/3 phosphorylation. In contrast, the overexpression of miR-140-5p decreases the expression levels of collagen I, collagen IV, and α-SMA, enhances E-cadherin expression, and inhibits the phosphorylation of Smad-2/3 in HK2 cells treated with TGF-β1. The dual-luciferase reporter assay revealed that TGFBR1 is a direct target gene of miR-140-5p. The enforced expression of miR-140-5p significantly inhibited the expression of TGFBR1 in HK2 cells. Furthermore, the knockdown of TGFBR1 has a similar effect of miR-140-5p overexpression on blocking the TGF-β1/smad signal pathway activation. In contrast, the overexpression of TGFBR1 reverses the effect of miR-140-5p inhibition on the activation of the TGF-β1/smad signal pathway. This study demonstrates that miR-140-5p regulates the TGF-β1/smad signaling pathway by suppressing the expression of TGFBR1. Therefore, miR-140-5p may have a therapeutic potential for preventing fibrotic kidney diseases through inhibiting the TGF-β1/Smad signaling pathway by directly targeting TGFBR1.

Inhibition of transforming growth factor β1 signaling in resident interstitial cells attenuates profibrotic gene expression and preserves erythropoietin production during experimental kidney fibrosis in mice

“…2,[11][12][13][14]29,58 It has been reported that renal interstitial PDGFR-β + cells acquire α-SMA expression during UUO, therefore we used α-SMA as a marker for myofibroblast formation. 31,59 Although profibrotic gene expression was reduced in TGFβ-R2ko mice, myofibroblast formation (as measured by α-SMA) and ECM deposition ( fig. 6 and 7) were unchanged compared to control animals in both fibrosis models.…”

MicroRNAs as Potential Biomarkers for the Diagnosis of Chronic Kidney Disease: A Systematic Review and Meta-Analysis

“…Bao et al (46) found that the inhibition of miR-21 activation by blocking the PTEN/Akt pathway in IgAN prevented the fibrogenic activation in podocytes and renal tubular cells. Liao et al (47) showed that miR-140-5p can protect HK2 cells from TGF-β-induced renal fibrosis by directly targeting TGFBR1. In a word, we cannot ignore the fact that miRNA as a biomarker of CKD should be put into more research.…”

microRNA‐145‐5p attenuates acute lung injury via targeting ETS2

“…The protein sample was separated by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, transferred to a polyvinylidene fluoride membrane (Millipore, Burlington, MA), and blocked. Primary antibodies against ETS2 (1:200, Santa Cruz Biotechnology, Santa Cruz, CA), TGF‐β1 (1:1000, R&D Systems, Minneapolis, MN), Smad2/3 (1:1000, CST, Danvers, MA), and β‐actin (1:1000, Santa Cruz Biotechnology) were incubated with the blots overnight, as were secondary antibody for 2 h. Finally, the blots were developed with enhanced chemiluminescence reagents and analyzed by ImageJ (NIH, Bethesda, MD) 26 …”