Dataset Information

The NRF2-LOC344887 signaling axis suppresses pulmonary fibrosis.

ABSTRACT: Idiopathic pulmonary fibrosis (IPF) is a progressive and irreversible disease characterized by an increase in differentiation of fibroblasts to myofibroblasts and excessive accumulation of extracellular matrix in lung tissue. Pharmacological activation of NRF2 has proved to be a valuable antifibrotic approach, however the detailed mechanisms of how NRF2 mediates antifibrotic function remain unclear. In this study, we found that the antifibrotic function of sulforaphane (SFN), an NRF2 activator, was largely dependent on LOC344887, a long noncoding RNA. Two functional AREs were identified in both the promoter and intron 1 of LOC344887, which defines LOC344887 as a novel anti-fibrotic NRF2 target gene. RNA-seq analysis revealed that LOC344887 controls genes and signaling pathways associated with fibrogenesis. Deletion or downregulation of LOC344887 enhanced expression of CDH2/N-cadherin, as well as a number of other fibrotic genes and blunted the antifibrotic effects of SFN. Furthermore, LOC344887-mediated downregulation of fibrotic genes may involve the PI3K-AKT signaling pathway, as pharmacologic inhibition of PI3K activity blocked the effects of LOC344887 knockdown. Our findings demonstrate that NRF2-mediated LOC344887 upregulation contributes to the antifibrotic potential of SFN by repressing the expression of CDH2 and other fibrotic genes, providing novel insight into how NRF2 controls the regulatory networks of IPF. This study provides a better understanding of the molecular mechanisms of NRF2 activators against pulmonary fibrosis and presents a novel therapeutic axis for prevention and intervention of fibrosis-related diseases.

SUBMITTER: Liu P

PROVIDER: S-EPMC7573654 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive fibrotic disease with pathophysiological characteristics of transforming growth factor-β (TGF-β), and reactive oxygen species (ROS)-induced excessive fibroblast-to-myofibroblast transition and extracellular matrix deposition. Macrophages are closely involved in the development of fibrosis. Nuclear factor erythroid 2 related factor 2 (Nrf2) is a key molecule regulating ROS and TGF-β expression. Therefore, Nrf2 signaling modulation might be a promising therapy for fibrosis. The inhalation-based drug delivery can reduce systemic side effects and improve therapeutic effects, and is currently receiving increasing attention, but direct inhaled drugs are easily cleared and difficult to exert their efficacy. Therefore, we aimed to design a ROS-responsive liposome for the Nrf2 agonist dimethyl fumarate (DMF) delivery in the fibrotic lung. Moreover, we explored its therapeutic effect on pulmonary fibrosis and macrophage activation.ResultsWe synthesized DMF-loaded ROS-responsive DSPE-TK-PEG@DMF liposomes (DTP@DMF NPs). DTP@DMF NPs had suitable size and negative zeta potential and excellent capability to rapidly release DMF in a high-ROS environment. We found that macrophage accumulation and polarization were closely related to fibrosis development, while DTP@DMF NPs could attenuate macrophage activity and fibrosis in mice. RAW264.7 and NIH-3T3 cells coculture revealed that DTP@DMF NPs could promote Nrf2 and downstream heme oxygenase-1 (HO-1) expression and suppress TGF-β and ROS production in macrophages, thereby reducing fibroblast-to-myofibroblast transition and collagen production by NIH-3T3 cells. In vivo experiments confirmed the above findings. Compared with direct DMF instillation, DTP@DMF NPs treatment presented enhanced antifibrotic effect. DTP@DMF NPs also had a prolonged residence time in the lung as well as excellent biocompatibility.ConclusionsDTP@DMF NPs can reduce macrophage-mediated fibroblast-to-myofibroblast transition and extracellular matrix deposition to attenuate lung fibrosis by upregulating Nrf2 signaling. This ROS-responsive liposome is clinically promising as an ideal delivery system for inhaled drug delivery.

Project description:Idiopathic pulmonary fibrosis (IPF) is the most common form of idiopathic interstitial pneumonia with an increasing incidence. In the present study, Genome Expression Omnibus (GEO) datasets (GSE10667, GSE24206 and GSE32537) were applied to identify lncRNA DLEU2 in IPF. Through prediction using starBase, TargetScan, miRTarBase and miRDB, tripartite motif containing 2 (TRIM2) and prostaglandin F2 receptor inhibitor (PTGFRN) were found to be upregulated in IPF. DLEU2 expression, the mRNA expression of TRIM2 and PTGFRN, and miR‑369‑3p expression in A549 cells and lung tissues were detected by RT‑qPCR. The protein expression of TRIM2 and PTGFRN in lung tissues and A549 cells was detected by western blot analysis. The proliferation and migration of A549 cells was respectively detected by CCK‑8 assay and wound healing assay. The expression of collagen I, α‑smooth muscle actin (SMA) and E‑cadherin was detected by immunofluorescence assay in A549 cells, and collagen I expression was detected by immunohistochemistry assay in lung tissues. The expression of collagen I, α‑SMA and E‑cadherin was also detected by western blot analysis in A549 cells and lung tissues. Dual‑luciferase reporter assay was used to confirm the association between DLEU2 and miR‑369‑3p, and miR‑369‑3p and TRIM2. As a result, DLEU2 expression was found to be upregulated in IPF and in transforming growth factor (TGF)‑β1‑stimulated A549 cells. The silencing of DLEU2 inhibited the TGF‑β1‑induced proliferation, migration and epithelial‑mesenchymal transition (EMT) of A549 cells and bleomycin (BLM)‑induced pulmonary fibrosis in mice. TRIM2 expression was increased and miR‑369‑3p expression was decreased in the lung tissues of mice with BLM‑induced fibrosis and in TGF‑β1‑stimulated A549 cells. DLEU2 directly targeted miR‑369‑3p. The effect of the silencing of DLEU2 on TGF‑β1‑stimulated A549 cells was suppressed by the silencing of miR‑369‑3p. TRIM2 was the target protein of miR‑369‑3p. On the whole, the present study demonstrates that the silencing of DLEU2 suppressed IPF by upregulating miR‑369‑3p expression and downregulating TRIM2 expression.

Project description:BackgroundIdiopathic pulmonary fibrosis is a persistent disease of the lung interstitium for which there is no efficacious pharmacological therapy. Protodioscin, a steroidal saponin, possesses diverse pharmacological properties; however, its function in pulmonary fibrosis is yet to be established. Hence, in this investigation, it was attempted to figure out the anti-pulmonary fibrosis influences of protodioscin and its pharmacological properties related to oxidative stress.MethodsA mouse lung fibrosis model was generated using tracheal injections of bleomycin, followed by intraperitoneal injection of different concentrations of protodioscin, and the levels of oxidative stress and fibrosis were detected in the lungs. Multiple fibroblasts were treated with TGF-β to induce their transition to myofibroblasts. It was attempted to quantify myofibroblast markers' expression levels and reactive oxygen species levels as well as Nrf2 activation after co-incubation of TGF-β with fibroblasts and different concentrations of protodioscin. The influence of protodioscin on the expression and phosphorylation of p62, which is associated with Nrf2 activation, were detected, and p62 related genes were predicted by STRING database. The effects of Nrf2 inhibitor or silencing of the Nrf2, p62 and NBR1 genes, respectively, on the activation of Nrf2 by protodioscin were examined. The associations between p62, NBR1, and Keap1 in the activation of Nrf2 by protodioscin was demonstrated using a co-IP assay. Nrf2 inhibitor were used when protodioscin was treated in mice with pulmonary fibrosis and lung tissue fibrosis and oxidative stress levels were detected.ResultsIn vivo, protodioscin decreased the levels of fibrosis markers and oxidative stress markers and activated Nrf2 in mice with pulmonary fibrosis, and these effects were inhibited by Nrf2 inhibitor. In vitro, protodioscin decreased the levels of myofibroblast markers and oxidative stress markers during myofibroblast transition and promoted Nrf2 downstream gene expression, with reversal of these effects after Nrf2, p62 and NBR1 genes were silenced or Nrf2 inhibitors were used, respectively. Protodioscin promoted the binding of NBR1 to p62 and Keap1, thereby reducing Keap1-Nrf2 binding.ConclusionThe NBR1-p62-Nrf2 axis is targeted by protodioscin to reduce oxidative stress and inhibit pulmonary fibrosis.

Dataset Information

The NRF2-LOC344887 signaling axis suppresses pulmonary fibrosis.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets