GRK2 promotes activation of lung fibroblast cells and contributes to pathogenesis of pulmonary fibrosis through increasing Smad3 expression

2021 ◽  
Author(s):  
Yanhui Li ◽  
Ying Sun ◽  
Nan Wu ◽  
Haichun Ma
Keyword(s):  
Pulmonary Fibrosis ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Fibroblast Cell ◽  
Cell Types ◽  
Lung Fibroblast ◽  
Lung Fibroblasts ◽  
Fibroblast Cells ◽  
Smad3 Expression ◽  
Tgf Β1

Pulmonary fibrosis is a chronic, progressive, and irreversible interstitial lung disease. Transforming growth factor beta1 (TGF-β1) plays a major role in lung fibroblast cell differentiation to myofibroblast cells and production of extracellular matrix, which are hallmarks of pulmonary fibrosis. G protein-coupled receptor kinase-2 (GRK2) has been shown to play controversial roles in TGF-β1-induced signal transduction in different cell types; however, the roles of GRK2 in TGF-β1-induced activation of lung fibroblast cells and development of pulmonary fibrosis have not been revealed. In this study, we found that GRK2 levels were induced in lungs and isolated fibroblast cells in a murine model of pulmonary fibrosis, as well as TGF-β1-treated lung fibroblasts. GRK2 levels were not changed in lungs in the injury phase of pulmonary fibrosis. Post-treatment with GRK2 inhibitor reduced ECM accumulation in lungs in bleomycin-challenged mice, suggesting that GRK2 activation contributes to the progressive phase of pulmonary fibrosis. Inhibition or downregulation of GRK2 attenuates fibronectin, collagen, and α-smooth muscle actin expression in TGF-β1-induced lung fibroblast cells or myofibroblast cells isolated from pulmonary fibrosis patients. Further, we showed that GRK2 regulates Smad3 expression, indicating that inhibition of GRK2 attenuates ECM accumulation through downregulation of Smad3 expression. This study reveals that GRK2 is a therapeutic target in treating pulmonary fibrosis and inhibition of GRK2 dampens pulmonary fibrosis by suppression of Smad3 expression, eventually attenuating TGF-β1 signal pathway and ECM accumulation.

Inhibition of miR-182-5p attenuates pulmonary fibrosis via TGF-β/Smad pathway

2019 ◽  
Vol 39 (5) ◽  
pp. 683-695 ◽  
Author(s):  
Y Chen ◽  
Q Zhang ◽  
Y Zhou ◽  
Z Yang ◽  
M Tan
Keyword(s):  
Pulmonary Fibrosis ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Lung Fibroblasts ◽  
In Vitro Assays ◽  
Luciferase Reporter ◽  
High Morbidity ◽  
Human Embryonic Lung ◽  
Promising Therapeutic Approach ◽  
Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive lung disease with high morbidity and mortality. miR-182-5p is overexpressed in several fibrosis-related diseases but its effect in pulmonary fibrosis has not been reported yet. To investigate the function of miR-182-5p in pulmonary fibrosis, we established bleomycin (BLM)-induced fibrotic mice model and transforming growth factor-β1 (TGF-β1)-treated human embryonic lung fibroblasts model. In this study, miR-182-5p was highly expressed in pulmonary tissues of BLM-induced fibrotic mice. The content of hydroxyproline and TGF-β1 was decreased by downregulating the expression of miR-182-5p, indicating that fibrosis was alleviated in mice treated with Lentivirus-anti-miR-182-5p.Quantification of fibrosis-related proteins demonstrated that downregulation of miR-182-5p inhibited the expression of profibrotic proteins (fibronectin, α-smooth muscle actin, p-Smad2/p-Smad3) as well as enhanced the level of Smad7. In vitro assays validated that miR-182-5p was induced by TGF-β1 with the function of promoting fibrosis. In dual-luciferase reporter assay, Smad7 was demonstrated to be negatively regulated by miR-182-5p. Moreover, the effect of knocking down miR-182-5p on inhibiting fibrosis was achieved by upregulating the expression of Smad7. Therefore, miR-182-5p can be regarded as a biomarker of IPF and its inhibition may be a promising therapeutic approach in treating IPF.

scholarly journals Cereblon contributes to the development of pulmonary fibrosis via inactivation of adenosine monophosphate-activated protein kinase α1

2021 ◽  
Author(s):  
Hyo Jae Kang ◽  
Kyung Jin Lee ◽  
Jisu Woo ◽  
Jiyeon Kim ◽  
Yun Kyu Kim ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Pulmonary Fibrosis ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Adenosine Monophosphate ◽  
Lavage Fluid ◽  
Lung Fibroblasts ◽  
Proliferation And Differentiation ◽  
Tgf Β1

AbstractPulmonary fibrosis is a progressive and lethal lung disease characterized by the proliferation and differentiation of lung fibroblasts and the accumulation of extracellular matrices. Since pulmonary fibrosis was reported to be associated with adenosine monophosphate-activated protein kinase (AMPK) activation, which is negatively regulated by cereblon (CRBN), we aimed to determine whether CRBN is involved in the development of pulmonary fibrosis. Therefore, we evaluated the role of CRBN in bleomycin (BLM)-induced pulmonary fibrosis in mice and in transforming growth factor-beta 1 (TGF-β1)-induced differentiation of human lung fibroblasts. BLM-induced fibrosis and the mRNA expression of collagen and fibronectin were increased in the lung tissues of wild-type (WT) mice; however, they were significantly suppressed in Crbn knockout (KO) mice. While the concentrations of TGF-β1/2 in bronchoalveolar lavage fluid were increased via BLM treatment, they were similar between BLM-treated WT and Crbn KO mice. Knockdown of CRBN suppressed TGF-β1-induced activation of small mothers against decapentaplegic 3 (SMAD3), and overexpression of CRBN increased it. TGF-β1-induced activation of SMAD3 increased α-smooth muscle actin (α-SMA) and collagen levels. CRBN was found to be colocalized with AMPKα1 in lung fibroblasts. CRBN overexpression inactivated AMPKα1. When cells were treated with metformin (an AMPK activator), the CRBN-induced activation of SMAD3 and upregulation of α-SMA and collagen expression were significantly suppressed, suggesting that increased TGF-β1-induced activation of SMAD3 via CRBN overexpression is associated with AMPKα1 inactivation. Taken together, these data suggest that CRBN is a profibrotic regulator and maybe a potential target for treating lung fibrosis.

Sodium Arsenite Inhibits Lung Fibroblast Differentiation and Pulmonary Fibrosis

Pharmacology ◽  
2019 ◽  
Vol 104 (5-6) ◽  
pp. 368-376 ◽  
Author(s):  
Hao Jiao ◽  
Jieqiong Song ◽  
Xia Sun ◽  
Dong Sun ◽  
Ming Zhong
Keyword(s):  
Pulmonary Fibrosis ◽  
Sodium Arsenite ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Lavage Fluid ◽  
Lung Fibroblast ◽  
Lung Fibroblasts ◽  
Nadph Oxidase 4 ◽  
Normal Human

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease with a high mortality and poor prognosis. Transforming growth factor (TGF)-β plays crucial roles in the pathogenesis of IPF. To investigate the role of sodium arsenite (SA) on fibroblast differentiation and pulmonary fibrosis, we checked the effects of SA on TGF-β-induced normal human lung fibroblasts (NHLFs) differentiation, and the anti-fibrotic effect of SA on bleomycin (BLM)-induced pulmonary fibrosis in mouse. SA treatment significantly inhibits α-smooth muscle actin and fibronectin (FN) expression in TGF-β treated NHLFs; and SA also inhibits TGF-β stimulated expression of NADPH oxidase 4 and accumulation of intracellular reactive oxygen species. TGF-β-induced the phosphorylation of ERK and Smad3 were also blocked by SA. The administration of SA (IP) suppressed BLM-induced lung fibrosis characterized as the inhibition of collagen deposition, TGF-β accumulation in bronchoalveolar lavage fluid, and the expression of FN and collagen 1a2 in lung tissue. This study revealed that SA inhibits TGF-β-induced lung fibroblast differentiation and BLM-induced pulmonary fibrosis in mice, suggesting that SA could be a potential therapeutic approach to IPF.

scholarly journals Butyrate Prevents TGF-β1-Induced Alveolar Myofibroblast Differentiation and Modulates Energy Metabolism

Metabolites ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 258
Author(s):  
Hyo Yeong Lee ◽  
Somi Nam ◽  
Mi Jeong Kim ◽  
Su Jung Kim ◽  
Sung Hoon Back ◽  
...  
Keyword(s):  
Energy Metabolism ◽  
Pulmonary Fibrosis ◽  
Transforming Growth Factor ◽  
Mitochondrial Dynamics ◽  
Tca Cycle ◽  
Lung Fibroblasts ◽  
Myofibroblast Differentiation ◽  
Pulmonary Fibroblasts ◽  
Matrix Deposition ◽  
Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is a serious lung disease characterized by excessive collagen matrix deposition and extracellular remodeling. Signaling pathways mediated by fibrotic cytokine transforming growth factor β1 (TGF-β1) make important contributions to pulmonary fibrosis, but it remains unclear how TGF-β1 alters metabolism and modulates the activation and differentiation of pulmonary fibroblasts. We found that TGF-β1 lowers NADH and NADH/NAD levels, possibly due to changes in the TCA cycle, resulting in reductions in the ATP level and oxidative phosphorylation in pulmonary fibroblasts. In addition, we showed that butyrate (C4), a short chain fatty acid (SCFA), exhibits potent antifibrotic activity by inhibiting expression of fibrosis markers. Butyrate treatment inhibited mitochondrial elongation in TGF-β1-treated lung fibroblasts and increased the mitochondrial membrane potential (MMP). Consistent with the mitochondrial observations, butyrate significantly increased ADP, ATP, NADH, and NADH/NAD levels in TGF-β1-treated pulmonary fibroblasts. Collectively, our findings indicate that TGF-β1 induces changes in mitochondrial dynamics and energy metabolism during myofibroblast differentiation, and that these changes can be modulated by butyrate, which enhances mitochondrial function.

scholarly journals P-Rex1 Cooperates With TGFβR2 to Drive Lung Fibroblast Migration in Pulmonary Fibrosis

2021 ◽  
Vol 12 ◽  
Author(s):  
Qing Liang ◽  
Yanhua Chang ◽  
Jing Liu ◽  
Yan Yu ◽  
Wancheng Qiu ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Lung Fibroblast ◽  
Alveolar Epithelial Cells ◽  
Lung Fibroblasts ◽  
Mouse Lung ◽  
Nucleotide Exchange ◽  
Alveolar Epithelial ◽  
Fibroblast Migration ◽  
Overexpression System ◽  
Tgf Β1

Pulmonary fibrosis is a kind of interstitial lung disease with progressive pulmonary scar formation, leading to irreversible loss of lung functions. The TGF-β1/Smad signaling pathway plays a key role in fibrogenic processes. It is associated with the increased synthesis of extracellular matrix, enhanced proliferation of fibroblasts, and transformation of alveolar epithelial cells into interstitial cells. We investigated P-Rex1, a PIP3-Gβγ–dependent guanine nucleotide exchange factor (GEF) for Rac, for its potential role in TGF-β1–induced pulmonary fibrosis. A high expression level of P-Rex1 was identified in the lung tissue of patients with pulmonary fibrosis than that from healthy donors. Using the P-Rex1 knockdown and overexpression system, we established a novel player of P-Rex1 in mouse lung fibroblast migration. P-Rex1 contributed to fibrogenic processes in lung fibroblasts by targeting the TGF-β type Ⅱ receptor (TGFβR2). The RNA-seq analysis for expression profiling confirmed the modulation of P-Rex1 in cell migration and the involvement of P-Rex1 in TGF-β1 signaling. These results identified P-Rex1 as a signaling molecule involved in TGF-β1–induced pulmonary fibrosis, suggesting that P-Rex1 may be a potential target for pulmonary fibrosis treatment.

scholarly journals HDAC8 inhibition ameliorates pulmonary fibrosis

2019 ◽  
Vol 316 (1) ◽  
pp. L175-L186 ◽  
Author(s):  
Shigeki Saito ◽  
Yan Zhuang ◽  
Takayoshi Suzuki ◽  
Yosuke Ota ◽  
Marjorie E. Bateman ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Pulmonary Fibrosis ◽  
Transforming Growth Factor ◽  
Therapeutic Potential ◽  
Smooth Muscle Actin ◽  
Lung Fibroblasts ◽  
Peroxisome Proliferator ◽  
Collagen Gels ◽  
Cell Contractility

Idiopathic pulmonary fibrosis (IPF) is a fibroproliferative lung disease, and fibroblast-myofibroblast differentiation (FMD) is thought to be a key event in the pathogenesis of IPF. Histone deacetylase-8 (HDAC8) has been shown to associate with α-smooth muscle actin (α-SMA; a marker of FMD) and regulates cell contractility in vascular smooth muscle cells. However, the role of HDAC8 in FMD or pulmonary fibrosis has never been reported. This study investigated the role of HDAC8 in pulmonary fibrosis with a focus on FMD. We observed that HDAC8 expression was increased in IPF lung tissue as well as transforming growth factor (TGF)β1-treated normal human lung fibroblasts (NHLFs). Immunoprecipitation experiments revealed that HDAC8 was associated with α-SMA in TGFβ1-treated NHLFs. HDAC8 inhibition with NCC170 (HDAC8-selective inhibitor) repressed TGFβ1-induced fibroblast contraction and α-SMA protein expression in NHLFs cultured in collagen gels. HDAC8 inhibition with HDAC8 siRNA also repressed TGFβ1-induced expression of profibrotic molecules such as fibronectin and increased expression of antifibrotic molecules such as peroxisome proliferator-activated receptor-γ (PPARγ). Chromatin immunoprecipitation quantitative PCR using an antibody against H3K27ac (histone H3 acetylated at lysine 27; a known HDAC8 substrate and a marker for active enhancers) suggested that HDAC8 inhibition with NCC170 ameliorated TGFβ1-induced loss of H3K27ac at the PPARγ gene enhancer. Furthermore, NCC170 treatment significantly decreased fibrosis measured by Ashcroft score as well as expression of type 1 collagen and fibronectin in bleomycin-treated mouse lungs. These data suggest that HDAC8 contributes to pulmonary fibrosis and that there is a therapeutic potential for HDAC8 inhibitors to treat IPF as well as other fibrotic lung diseases.

scholarly journals LTBP2 is secreted from lung myofibroblasts and is a potential biomarker for idiopathic pulmonary fibrosis

2018 ◽  
Vol 132 (14) ◽  
pp. 1565-1580 ◽  
Author(s):  
Yasunori Enomoto ◽  
Sayomi Matsushima ◽  
Kiyoshi Shibata ◽  
Yoichiro Aoshima ◽  
Haruna Yagi ◽  
...  
Keyword(s):  
Idiopathic Pulmonary Fibrosis ◽  
Pulmonary Fibrosis ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Bootstrap Method ◽  
Transforming Growth Factor Β ◽  
Lung Fibroblasts ◽  
Potential Biomarker ◽  
Fibrotic Process ◽  
Mouse Lungs

Although differentiation of lung fibroblasts into α-smooth muscle actin (αSMA)-positive myofibroblasts is important in the progression of idiopathic pulmonary fibrosis (IPF), few biomarkers reflecting the fibrotic process have been discovered. We performed microarray analyses between FACS-sorted steady-state fibroblasts (lineage (CD45, TER-119, CD324, CD31, LYVE-1, and CD146)-negative and PDGFRα-positive cells) from untreated mouse lungs and myofibroblasts (lineage-negative, Sca-1-negative, and CD49e-positive cells) from bleomycin-treated mouse lungs. Amongst several genes up-regulated in the FACS-sorted myofibroblasts, we focussed on Ltbp2, the gene encoding latent transforming growth factor-β (TGF-β) binding protein-2 (LTBP2), because of the signal similarity to Acta2, which encodes αSMA, in the clustering analysis. The up-regulation was reproduced at the mRNA and protein levels in human lung myofibroblasts induced by TGF-β1. LTBP2 staining in IPF lungs was broadly positive in the fibrotic interstitium, mainly as an extracellular matrix (ECM) protein; however, some of the αSMA-positive myofibroblasts were also stained. Serum LTBP2 concentrations, evaluated using ELISA, in IPF patients were significantly higher than those in healthy volunteers (mean: 21.4 compared with 12.4 ng/ml) and showed a negative correlation with % predicted forced vital capacity (r = −0.369). The Cox hazard model demonstrated that serum LTBP2 could predict the prognosis of IPF patients (hazard ratio for death by respiratory events: 1.040, 95% confidence interval: 1.026–1.054), which was validated using the bootstrap method with 1000-fold replication. LTBP2 is a potential prognostic blood biomarker that may reflect the level of differentiation of lung fibroblasts into myofibroblasts in IPF.

scholarly journals Anlotinib Inhibits PFKFB3-Driven Glycolysis in Myofibroblasts to Reverse Pulmonary Fibrosis

2021 ◽  
Vol 12 ◽  
Author(s):  
Weimou Chen ◽  
Jinming Zhang ◽  
Wenshan Zhong ◽  
Yuanyuan Liu ◽  
Ye Lu ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Lung Fibroblasts ◽  
Current Evidence ◽  
Extracellular Acidification ◽  
Fatal Disease ◽  
Growth Factor Beta ◽  
Lactate Levels ◽  
Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is a fatal disease in which the normal alveolar network is gradually replaced by fibrotic scars. Current evidence suggests that metabolic alterations correlate with myofibroblast activation in IPF. Anlotinib has been proposed to have antifibrotic effects, but the efficacy and mechanisms of anlotinib against lung fibrosis have not been systematically evaluated. The antifibrotic effects of anlotinib were evaluated in bleomycin-induced mouse models and transforming growth factor-beta 1 (TGF-β1)-stimulated lung fibroblasts. We measured lactate levels, 2-NBDG glucose uptake and the extracellular acidification rate (ECAR) to assess glycolysis in fibroblasts. RNA-protein coimmunoprecipitation (RIP) and polysome analyses were performed to investigate novel mechanisms of glycolytic reprogramming in pulmonary fibrosis. We found that anlotinib diminished myofibroblast activation and inhibited the augmentation of glycolysis. Moreover, we show that PCBP3 posttranscriptionally increases PFKFB3 expression by promoting its translation during myofibroblast activation, thus promoting glycolysis in myofibroblasts. Regarding mechanism, anlotinib exerts potent antifibrotic effects by downregulating PCBP3, reducing PFKFB3 translation and inhibiting glycolysis in myofibroblasts. Furthermore, we observed that anlotinib had preventative and therapeutic antifibrotic effects on bleomycin-induced pulmonary fibrosis. Therefore, we identify PCBP3 as a protein involved in the regulation of glycolysis reprogramming and lung fibrogenesis and propose it as a therapeutic target for pulmonary fibrosis. Our data suggest that anlotinib has antifibrotic effects on the lungs, and we provide a novel mechanism for this effect. Anlotinib may constitute a novel and potent candidate for the treatment of pulmonary fibrosis.

scholarly journals TGF-β1/SMOC2/AKT and ERK axis regulates proliferation, migration, and fibroblast to myofibroblast transformation in lung fibroblast, contributing with the asthma progression

Hereditas ◽  
2021 ◽  
Vol 158 (1) ◽  
Author(s):  
Yuebin Wang ◽  
Huike Yang ◽  
Xian Su ◽  
Anqiang Cao ◽  
Feng Chen ◽  
...  
Keyword(s):  
Calcium Binding ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Transforming Growth Factor Β ◽  
Chronic Respiratory Disease ◽  
Lung Fibroblasts ◽  
Promoting Effect ◽  
And Migration ◽  
Tgf Β1 ◽  
Proliferation And Migration

Abstract Background Asthma is a common chronic respiratory disease that influences 300 million people all over the world. However, the pathogenesis of asthma has not been fully elucidated. It has been reported that transforming growth factor-β (TGF-β) can activate myofibroblasts. Moreover, the fibroblast to myofibroblast transformation (FMT) can be triggered by TGF-β, which is a major mediator of subepithelial fibrosis. Secreted modular calcium-binding protein 2 (SMOC2) is a member of cysteine (SPARC) family and is involved in the progression of multiple diseases. However, its role in asthma remains poorly understood. RT-qPCR evaluated the expression of SMOC2. Bromodeoxyuridine assay and wound-healing assay detected the proliferation and migration of lung fibroblasts, respectively. IF staining was performed to assess the expression of α-smooth muscle actin (α-SMA). Western blot analysis detected the levels of proteins. Flow cytometry was utilized for determination of the number of myofibroblasts. Results We found the expression of SMOC2 was upregulated by the treatment of TGF-β1 in lung fibroblasts. In addition, SMOC2 promoted the proliferation and migration of lung fibroblasts. More importantly, SMOC2 accelerated FMT of lung fibroblasts. Furthermore, SMOC2 was verified to control the activation of AKT and ERK. Rescue assays showed that the inhibition of AKT and ERK pathway reversed the promoting effect of SMOC2 overexpression on proliferation, migration and FMT in lung fibroblasts. Conclusions This work demonstrated that SMOC2 modulated TGF-β1-induced proliferation, migration and FMT in lung fibroblasts and may promote asthma, which potentially provided a novel therapeutic target for the management of asthma.

scholarly journals NADPH oxidase DUOX1 sustains TGF-β1 signalling and promotes lung fibrosis

2020 ◽  
pp. 1901949
Author(s):  
Ruy Andrade Louzada ◽  
Raphaël Corre ◽  
Rabii Ameziane El Hassani ◽  
Lydia Meziani ◽  
Madeleine Jaillet ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Pulmonary Fibrosis ◽  
Nadph Oxidase ◽  
Lung Fibrosis ◽  
Transforming Growth Factor ◽  
Lung Fibroblasts ◽  
Mouse Lung ◽  
Epithelial Surface ◽  
Tgf Β1

Interstitial lung fibroblast activation coupled with extracellular matrix production is a pathological signature of pulmonary fibrosis, and is governed by transforming growth factor (TGF-β1)/Smad signalling. TGF-β1 and oxidative stress cooperate to drive fibrosis. Cells can produce reactive oxygen species (ROS) through activation and/or induction of NADPH oxidases, such as dual oxidase (DUOX1/2). Since DUOX enzymes, as extracellular H2O2-generating systems, are involved in extracellular matrix formation and in wound healing in different experimental models, we hypothesised that DUOX-based NADPH oxidase plays a role in the pathophysiology of pulmonary fibrosis.Our in vivo data (IPF patients and mouse models of lung fibrosis) showed that the NADPH oxidase DUOX1 is induced in response to lung injury. DUOX1-deficient mice (DUOX1+/- and DUOX1-/-) had an attenuated fibrotic phenotype. In addition to being highly expressed at the epithelial surface of airways, DUOX1 appears to be also well expressed in the fibroblastic foci of remodelled lungs. By using primary human and mouse lung fibroblasts, we showed that TGF-β1 upregulates DUOX1 and its maturation factor DUOXA1 and that DUOX1-derived H2O2 promoted the duration of TGF-β1-activated Smad3 phosphorylation by preventing phospho-Smad3 degradation. Analysis of the mechanism revealed that DUOX1 inhibited the interaction between phospho-Smad3 and the ubiquitin ligase NEDD4L, preventing NEDD4L-mediated ubiquitination of phospho-Smad3 and its targeting for degradation.These findings highlight a role for DUOX1-derived H2O2 in a positive feedback that amplifies the signalling output of the TGF-β1 pathway and identify DUOX1 as a new therapeutic target in pulmonary fibrosis.

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