Bleomycin-induced Pulmonary Fibrosis Research Articles

Supramolecular Nanofibers Ameliorate Bleomycin-Induced Pulmonary Fibrosis by Restoring Autophagy.

Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal interstitial lung disease, with limited therapeutic options available. Impaired autophagy resulting from aberrant TRB3/p62 protein-protein interactions (PPIs) contributes to the progression of IPF. Restoration of autophagy by modulating the TRB3/p62 PPIs has rarely been reported for the treatment of IPF. Herein, peptide nanofibers are developed that specifically bind to TRB3 protein and explored their potential as a therapeutic approach for IPF. By conjugating with the self-assembling fragment (Ac-GFFY), a TRB3-binding peptide motif A2 allows for the formation of nanofibers with a stable α-helix secondary structure. The resulting peptide (Ac-GFFY-A2) nanofibers exhibit specific high-affinity binding to TRB3 protein in saline buffer and better capacity of cellular uptake to A2 peptide. Furthermore, the TRB3-targeting peptide nanofibers efficiently interfere with the aberrant TRB3/p62 PPIs in activated fibroblasts and fibrotic lung tissue of mice, thereby restoring autophagy dysfunction. The TRB3-targeting peptide nanofibers inhibit myofibroblast differentiation, collagen production, and fibroblast migration in vitro is demonstrated, as well as bleomycin-induced pulmonary fibrosis in vivo. This study provides a supramolecular method to modulate PPIs and highlights a promising strategy for treating IPF diseases by restoring autophagy.

Kefir peptides mitigate bleomycin-induced pulmonary fibrosis in mice through modulating oxidative stress, inflammation and gut microbiota

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive and life-threatening lung disease with high mortality rates. The limited availability of effective drugs for IPF treatment, coupled with concerns regarding adverse effects and restricted responsiveness, underscores the need for alternative approaches. Kefir peptides (KPs) have demonstrated antioxidative, anti-inflammatory, and antifibrotic properties, along with the capability to modulate gut microbiota. This study aims to investigate the impact of KPs on bleomycin-induced pulmonary fibrosis. MethodsMice were treated with KPs for four days, followed by intratracheal injection of bleomycin for 21 days. Comprehensive assessments included pulmonary functional tests, micro-computed tomography (µ-CT), in vivo image analysis using MMPsense750, evaluation of inflammation- and fibrosis-related gene expression in lung tissue, and histopathological examinations. Furthermore, a detailed investigation of the gut microbiota community was performed using full-length 16 S rRNA sequencing in control mice, bleomycin-induced fibrotic mice, and KPs-pretreated fibrotic mice. ResultsIn KPs-pretreated bleomycin-induced lung fibrotic mice, notable outcomes included the absence of significant bodyweight loss, enhanced pulmonary functions, restored lung tissue architecture, and diminished thickening of inter-alveolar septa, as elucidated by morphological and histopathological analyses. Concurrently, a reduction in the expression levels of oxidative biomarkers, inflammatory factors, and fibrotic indicators was observed. Moreover, 16 S rRNA sequencing demonstrated that KPs pretreatment induced alterations in the relative abundances of gut microbiota, notably affecting Barnesiella_intestinihominis, Kineothrix_alysoides, and Clostridium_viride. ConclusionsKefir peptides exerted preventive effects, protecting mice against bleomycin-induced lung oxidative stress, inflammation, and fibrosis. These effects are likely linked to modifications in the gut microbiota community. The findings highlight the therapeutic potential of KPs in mitigating pulmonary fibrosis and advocate for additional exploration in clinical settings.

Elucidating the Mechanism of Buyanghuanwu Decoction Acting on Pulmonary Fibrosis based on Network Pharmacology and Animal Studies.

Buyanghuanwu Decoction (BYHWD) is a clinically proven prescription effective in treating pulmonary fibrosis (PF), but the molecular mechanism underlying its action remains unclear. The network pharmacology analysis was performed to elucidate the acting substances and related pathways of BYHWD in treating bleomycin (BLM) induced PF mouse. First, the pharmacologically active components and corresponding targets in BYHWD were identified through the TCMSP database and literature review. Second, PF¬-related targets were identified through the DisGeNet database. Then, the components-targets network of BYHWD in PF treatment was constructed using Cytoscape. The DAVID database was used for the enrichment analysis of GO terms and KEGG pathways. At last, the therapeutic effect of BYHWD on BLM-induced PF mice were verified, and the mRNA and protein expression of related targets was determined through RT-PCR and western blotting, respectively. The core component-target network contained 58 active components and 147 targets. Thirty-nine core targets were mainly involved in the regulation of biological functions and KEGG pathways, such as the positive regulation of nitric oxide biosynthesis and the TNF signaling pathway. These core targets were obtained through enrichment analysis. Moreover, animal studies revealed that BYHWD down-regulated the mRNA expression levels of TNF, IL-6, IL-1β, and NOS2 and inhibited NF-κB and p38 phosphorylation. The effects of BYHWD on PF mice are therapeutic, and its anti-PF mechanism mainly involves the effects on inflammatory factors and the NF-κB/p38 pathway.

Pirfenidone and nintedanib exert additive antifibrotic effects by the SPP1-AKT pathway in macrophages and fibroblasts

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease with high mortality rates. It has been shown that pirfenidone (PFD) and nintedanib (Ofev) can slow down the decline in lung function of IPF patients, but their efficacy remains suboptimal. Some studies have suggested that the combination of PFD and Ofev may yield promising results. However, there is a lack of research on the combined application of these two medications in the treatment of IPF. A mouse model of bleomycin-induced (BLM) pulmonary fibrosis was established to investigate the impact of combination therapy on pulmonary fibrosis of mice. The findings demonstrated a significant reduction in lung tissue damage in mice treated with the combination therapy. Subsequent transcriptome analysis identified the differential gene secreted phosphoprotein 1 (SPP1), which was found to be associated with macrophages and fibroblasts based on multiple immunofluorescence staining results. Analysis of a phosphorylated protein microarray indicated that SPP1 plays a regulatory role in macrophages and fibroblasts via the AKT pathway. Consequently, the regulation of macrophages and fibroblasts in pulmonary fibrosis by the combination of PFD and Ofev is mediated by SPP1 through the AKT pathway, potentially offering a novel therapeutic option for IPF patients. Further investigation into the targeting of SPP1 for the treatment of pulmonary fibrosis is warranted.

Sinomenine attenuates bleomycin-induced pulmonary fibrosis, inflammation, and oxidative stress by inhibiting TLR4/NLRP3/TGFβ signaling

Objective The present work concentrated on validating whether sinomenine alleviates bleomycin (BLM)-induced pulmonary fibrosis, inflammation, and oxidative stress. Methods A rat model of pulmonary fibrosis was constructed through intratracheal injection with 5 mg/kg BLM, and the effects of 30 mg/kg sinomenine on pulmonary inflammation, fibrosis, apoptosis, and 4-hydroxynonenal density were evaluated by hematoxylin and eosin staining, Masson’s trichrome staining, TUNEL staining, and immunohistochemistry. Hydroxyproline content and concentrations of inflammatory cytokines and oxidative stress markers were detected using corresponding kits. MRC-5 cells were treated with 10 ng/ml PDGF, and the effects of 1 mM sinomenine on cell proliferation were assessed by EdU assays. The mRNA expression of inflammatory cytokines and the protein levels of collagens, fibrosis markers, and key markers involved in the TLR4/NLRP3/TGFβ signaling were tested with RT-qPCR and immunoblotting analysis. Results Sinomenine attenuated pulmonary fibrosis and inflammation while reducing hydroxyproline content and the protein expression of collagens and fibrosis markers in BLM-induced pulmonary fibrosis rats. Sinomenine reduced apoptosis in lung samples of BLM-challenged rats by increasing Bcl-2 and reducing Bax and cleaved caspase-3 protein expression. In addition, sinomenine alleviated inflammatory response and oxidative stress in rats with pulmonary fibrosis induced by BLM. Moreover, sinomenine inhibited the TLR4/NLRP3/TGFβ signaling pathway in lung tissues of BLM-stimulated rats. Furthermore, TLR4 inhibitor, TAK-242, attenuated PDGF-induced fibroblast proliferation and collagen synthesis in MRC-5 cells. Conclusion Sinomenine attenuates BLM-caused pulmonary fibrosis, inflammation, and oxidative stress by inhibiting the TLR4/NLRP3/TGFβ signaling, indicating that sinomenine might become a therapeutic candidate to treat pulmonary fibrosis.

Mimosa pudica L. extract ameliorates pulmonary fibrosis via modulation of MAPK signaling pathways and FOXO3 stabilization

Ethnopharmacological relevanceIdiopathic pulmonary fibrosis (IPF) is a progressive fibrosing pulmonary disorder that has a poor prognosis and high mortality. Although there has been extensive effort to introduce several new anti-fibrotic agents in the past decade, IPF remains an incurable disease. Mimosa pudica L., an indigenous Vietnamese plant, has been empirically used to treat respiratory disorders. Nevertheless, the therapeutic effects of M. pudica (MP) on lung fibrosis and the mechanisms underlying those effects remain unclear. Aim of the studyThis study investigated the protective effect of a crude ethanol extract of the above-ground parts of MP against pulmonary fibrogenesis. Materials and methodsInflammatory responses triggered by TNFα in structural lung cells were examined in normal human lung fibroblasts and A549 alveolar epithelial cells using Western blot analysis, reverse transcription–quantitative polymerase chain reaction assays, and immunocytochemistry. The epithelial-to-mesenchymal transition (EMT) was examined via cell morphology observations, F-actin fluorescent staining, gene and protein expression measurements, and a wound-healing assay. Anti-fibrotic assays including collagen release, differentiation, and measurements of fibrosis-related gene and protein expression levels were performed on TGFβ-stimulated human lung fibroblasts and lung fibroblasts derived from mice with fibrotic lungs. Finally, in vitro anti-fibrotic activities were validated using a mouse model of bleomycin-induced pulmonary fibrosis. ResultsMP alleviated the inflammatory responses of A549 alveolar epithelial cells and lung fibroblasts, as revealed by inhibition of TNFα-induced chemotactic cytokine and chemokine expression, along with inactivation of the MAPK and NFκB signalling pathways. MP also partially reversed the TGFβ-promoted EMT via downregulation of mesenchymal markers in A549 cells. Importantly, MP decreased the expression levels of fibrosis-related genes/proteins including collagen I, fibronectin, and αSMA; moreover, it suppressed collagen secretion and prevented myofibroblast differentiation in lung fibroblasts. These effects were mediated by FOXO3 stabilization through suppression of TGFβ-induced ERK1/2 phosphorylation. MP consistently protected mice from the onset and progression of bleomycin-induced pulmonary fibrosis. ConclusionThis study explored the multifaceted roles of MP in counteracting the pathobiological processes of lung fibrosis. The results suggest that further evaluation of MP could yield candidate therapies for IPF.

Protective effects of microbial biosurfactants produced by Bacillus halotolerans and Candida parapsilosis on bleomycin-induced pulmonary fibrosis in mice: Impact of antioxidant, anti-inflammatory and anti-fibrotic properties via TGF-β1/Smad-3 pathway and miRNA-326

Idiopathic pulmonary fibrosis (IPF) is an irreversible disease which considered the most fatal pulmonary fibrosis. Pulmonary toxicity including IPF is the most severe adverse effect of bleomycin, the chemotherapeutic agent. Based on the fact that, exogenous surfactants could induce alveolar stabilization in many lung diseases, the aim of this study was to explore the effects of low cost biosurfactants, surfactin (SUR) and sophorolipids (SLs), against bleomycin-induced pulmonary fibrosis in mice due to their antioxidant, and anti-inflammatory properties. Surfactin and sophorolipids were produced by microbial conversion of frying oil and potato peel wastes using Bacillus halotolerans and Candida parapsilosis respectively. These biosurfactants were identified by FTIR, 1H NMR, and LC-MS/MS spectra. C57BL/6 mice were administered the produced biosurfactants daily at oral dose of 200 mg kg−1 one day after the first bleomycin dose (35 U/kg). We evaluated four study groups: Control, Bleomycin, Bleomycin+SUR, Bleomycin+SLs. After 30 days, lungs from each mouse were sampled for oxidative stress, ELISA, Western blot, histopathological, immunohistochemical analyses. Our results showed that the produced SUR and SLs reduced pulmonary oxidative stress and inflammatory response in the lungs of bleomycin induced mice as they suppressed SOD, CAT, and GST activities also reduced NF-κβ, TNF-α, and CD68 levels. Furthermore, biosurfactants suppressed the expression of TGF-β1, Smad-3, and p-JNK fibrotic signaling pathway in pulmonary tissues. Histologically, SUR and SLs protected against lung ECM deposition caused by bleomycin administration. Biosurfactants produced from microbial sources can inhibit the induced inflammatory and fibrotic responses in bleomycin-induced pulmonary fibrosis.

Role of transient receptor potential ankyrin 1 in idiopathic pulmonary fibrosis: modulation of M2 macrophage polarization

Idiopathic pulmonary fibrosis (IPF) poses significant challenges due to limited treatment options despite its complex pathogenesis involving cellular and molecular mechanisms. This study investigated the role of transient receptor potential ankyrin 1 (TRPA1) channels in regulating M2 macrophage polarization in IPF progression, potentially offering novel therapeutic targets. Using a bleomycin-induced pulmonary fibrosis model in C57BL/6J mice, we assessed the therapeutic potential of the TRPA1 inhibitor HC-030031. TRPA1 upregulation was observed in fibrotic lungs, correlating with worsened lung function and reduced survival. TRPA1 inhibition mitigated fibrosis severity, evidenced by decreased collagen deposition and restored lung tissue stiffness. Furthermore, TRPA1 blockade reversed aberrant M2 macrophage polarization induced by bleomycin, associated with reduced Smad2 phosphorylation in the TGF-β1-Smad2 pathway. In vitro studies with THP-1 cells treated with bleomycin and HC-030031 corroborated these findings, highlighting TRPA1's involvement in fibrotic modulation and macrophage polarization control. Overall, targeting TRPA1 channels presents promising therapeutic potential in managing pulmonary fibrosis by reducing pro-fibrotic marker expression, inhibiting M2 macrophage polarization, and diminishing collagen deposition. This study sheds light on a novel avenue for therapeutic intervention in IPF, addressing a critical need in the management of this challenging disease.Graphical abstract

Aging of alveolar type 2 cells induced by Lonp1 deficiency exacerbates pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a progressive and chronic disease that significantly impacts patient quality of life, and its incidence is on the rise. The pathogenesis of IPF remains poorly understood. Alveolar type 2 (AT2) cells are crucial in the onset and progression of IPF, yet the specific mechanisms involved are not well defined. Lon protease 1 (LONP1), known for its critical roles in various diseases, has an unclear function in IPF. Our research investigated the impact of Lonp1 gene deletion on AT2 cell functionality and its subsequent effect on IPF development. We generated a bleomycin-induced pulmonary fibrosis mouse model with a targeted Lonp1 knockout in AT2 cells and assessed the consequences on AT2 cell function and fibrosis progression. Additionally, we constructed the MLE12 cells with stable Lonp1 knockdown and utilized transcriptome sequencing to identify pathways altered by the Lonp1 knockdown. Our results indicated that mice with AT2 cell-specific Lonp1 knockout exhibited more severe fibrosis compared to controls. These mice exhibited a reduction in AT2 and AT1 cell populations, along with an increase in p53- and p21-positive AT2 cells. Lonp1 knockdown in MLE12 cells led to the upregulation of aging-associated pathways, with fibroblast growth factor 2 (Fgf2) gene emerging as a central gene interconnecting these pathways. Therefore, loss of Lonp1 appears to promote AT2 cell aging and exacerbate bleomycin-induced pulmonary fibrosis. Fgf2 emerges as a pivotal downstream gene associated with cellular senescence. This study uncovers the role of the Lonp1 gene in pulmonary fibrosis, presenting a novel target for investigating the pathological mechanisms and potential therapeutic approaches for IPF.

Loss of ZNF451 mediates fibroblast activation and promotes lung fibrosis

BackgroundNo effective therapies for pulmonary fibrosis (PF) exist because of the unclear molecular pathogenesis and the lack of effective therapeutic targets. Zinc finger protein 451 (ZNF451), a transcriptional regulator, plays crucial roles in the pathogenesis of several diseases. However, its expression pattern and function in PF remain unknown. This study was designed to investigate the role of ZNF451 in the pathogenesis of lung fibrosis.MethodsGEO dataset analysis, RT‒PCR, and immunoblot assays were used to examine the expression of ZNF451 in PF; ZNF451 knockout mice and ZNF451-overexpressing lentivirus were used to determine the importance of ZNF451 in PF progression; and migration assays, immunofluorescence staining, and RNA-seq analysis were used for mechanistic studies.ResultsZNF451 is downregulated and negatively associated with disease severity in PF. Compared with wild-type (WT) mice, ZNF451 knockout mice exhibited much more serious PF changes. However, ZNF451 overexpression protects mice from BLM-induced pulmonary fibrosis. Mechanistically, ZNF451 downregulation triggers fibroblast activation by increasing the expression of PDGFB and subsequently activating PI3K/Akt signaling.ConclusionThese findings uncover a critical role of ZNF451 in PF progression and introduce a novel regulatory mechanism of ZNF451 in fibroblast activation. Our study suggests that ZNF451 serves as a potential therapeutic target for PF and that strategies aimed at increasing ZNF451 expression may be promising therapeutic approaches for PF.

Shengxian decoction improves lung function in rats with bleomycin-induced idiopathic pulmonary fibrosis through the inhibition of PANoptosis

Ethnopharmacological relevanceShengxian decoction (SXD) is a classic Chinese medicinal formula that can effectively improve clinical symptoms and quality of life and delay disease progression in idiopathic pulmonary fibrosis (IPF) patients; however, the underlying mechanisms remain unclear. Aim of the studyThis study aimed to observe PANoptosis in bleomycin-induced IPF and to assess the efficacy and mechanism of action of SXD in the treatment of IPF. Materials and methodsFifty SD rats were randomly divided into the sham, IPF, IPF + pirfenidone (PFD), IPF + SXD-medium dose (SXD-M), and IPF + SXD-low dose (SXD-L) groups. Lung function analysis and microcomputed tomography imaging of the rats with IPF treated with oral pirfenidone or oral SXD for 28 days were performed. Hematoxylin and eosin (HE) staining and Masson's trichrome staining were used to observe pathological lung damage. Enzyme-linked immunosorbent assays (ELISAs) were used to determine the serum levels of IL-1β, IL-18, TNF-α, and IFN-γ. Pyroptosis, apoptosis, and necroptosis were assessed using TUNEL, TUNEL/caspase-1, and PI fluorescence staining, respectively. GSDMD, caspase-3, and MLKL were examined by immunohistochemistry. The expression of fibrin-, ZBP1-, pyroptosis-, apoptosis-, and necroptosis-related proteins in the lung tissue was determined by western blotting. ResultsSXD normalized lung function in rats with bleomycin-induced IPF and reduced serum inflammatory factor levels and lung tissue fibrosis. The underlying mechanism of action involves the inhibition of pyroptosis pathway proteins, such as NLRP3, caspase-1, cleaved caspase-1, and GSDMD; apoptotic pathway proteins, such as Bax, Bcl-2, cleaved caspase-3, and caspase-3; and necroptosis pathway proteins, such as RIPK1, RIPK3, p-MLKL and MLKL. These pathways are modulated by the PANoptosis initiator ZBP1. Notably, the efficacy of SXD is concentration dependent, with a medium dose exhibiting superior effectiveness compared to a low dose. ConclusionBleomycin induced PANoptosis in the lung tissue of rats with IPF. Additionally, SXD effectively delayed or reversed the early pathological changes in bleomycin-induced pulmonary fibrosis by inhibiting PANoptosis.

Selenite selectively kills lung fibroblasts to treat bleomycin-induced pulmonary fibrosis

BackgroundInterstitial lung disease (ILD) treatment is a critical unmet need. Selenium is an essential trace element for human life and an antioxidant that activates glutathione, but the gap between its necessity and its toxicity is small and requires special attention. Whether selenium can be used in the treatment of ILD remains unclear. MethodsWe investigated the prophylactic and therapeutic effects of selenite, a selenium derivative, in ILD using a murine model of bleomycin-induced idiopathic pulmonary fibrosis (IPF). We further elucidated the underlying mechanism using in vitro cell models and examined their relevance in human tissue specimens. The therapeutic effect of selenite in bleomycin-administered mice was assessed by respiratory function and histochemical changes. Selenite-induced apoptosis and reactive oxygen species (ROS) production in murine lung fibroblasts were measured. ResultsSelenite, administered 1 day (inflammation phase) or 8 days (fibrotic phase) after bleomycin, prevented and treated deterioration of lung function and pulmonary fibrosis in mice. Mechanistically, selenite inhibited the proliferation and induced apoptosis of murine lung fibroblasts after bleomycin treatment both in vitro and in vivo. In addition, selenite upregulated glutathione reductase (GR) and thioredoxin reductase (TrxR) in murine lung fibroblasts, but not in lung epithelial cells, upon bleomycin treatment. GR and TrxR inhibition eliminates the therapeutic effects of selenite. Furthermore, we found that GR and TrxR were upregulated in the human lung fibroblasts of IPF patient samples. ConclusionsSelenite induces ROS production and apoptosis in murine lung fibroblasts through GR and TrxR upregulation, thereby providing a therapeutic effect in bleomycin-induced IPF.

Geneticin ameliorates pulmonary fibrosis by attenuating the TGF-β/Smad via modulating AMPK/SIRT1 signaling

AimIdiopathic pulmonary fibrosis (IPF) is a chronic, progressive condition with unknown aetiology that causes the lung parenchyma to scar incessantly, lowering the quality of life and hastening death. In this investigation, we studied the anti-fibrotic activity of Geneticin (a derivative of gentamycin) using in vitro and in vivo models. Main methodsThe TGF-β-mediated differentiation model was adopted to investigate (fibrotic marker's levels/expression) the anti-fibrotic activity of geneticin (GNC) in in-vitro scenarios (Ll29 and DHLF cells). In vivo, the bleomycin (BLM)-induced pulmonary fibrosis model was employed by administering BLM intratracheally. Post 14 days of BLM administration, animals were treated with geneticin (6.25, 12.5, and 25 mg·kg−1) for another 14 days, and their therapeutic effect was investigated using a spectrum of techniques. Key findingsRTqPCR and western-blot results revealed that geneticin treatment significantly attenuated the TGF-β mediated fibrotic cascade of markers in both in-vitro and in-vivo models. Further, the BLM-induced pulmonary fibrosis model revealed, that geneticin dose-dependently reduced the BLM-induced inflammatory cell infiltrations, and thickness of the alveoli walls, improved the structural distortion of the lung, and aided in improving the survival rate of the rats. Picrosirus and Masson's trichrome staining indicated that geneticin therapy reduced collagen deposition and, as a result, lung functional characteristics were improved as assessed by flexivent. Mechanistic studies have shown that geneticin reduced fibrosis by attenuating the TGF-β/Smad through modulating the AMPK/SIRT1 signaling. SignificanceThese findings suggest that geneticin may be a promising therapeutic agent for the treatment of pulmonary fibrosis in clinical settings.

Ailanthone ameliorates pulmonary fibrosis by suppressing JUN-dependent MEOX1 activation

Pulmonary fibrosis poses a significant health threat with very limited therapeutic options available. In this study, we reported the enhanced expression of mesenchymal homobox 1 (MEOX1) in pulmonary fibrosis patients, especially in their fibroblasts and endothelial cells, and confirmed MEOX1 as a central orchestrator in the activation of profibrotic genes. By high-throughput screening, we identified Ailanthone (AIL) from a natural compound library as the first small molecule capable of directly targeting and suppressing MEOX1. AIL demonstrated the ability to inhibit both the activation of fibroblasts and endothelial-to-mesenchymal transition of endothelial cells when challenged by transforming growth factor-β1 (TGF-β1). In an animal model of bleomycin-induced pulmonary fibrosis, AIL effectively mitigated the fibrotic process and restored respiratory functions. Mechanistically, AIL acted as a suppressor of MEOX1 by disrupting the interaction between the transcription factor JUN and the promoter of MEOX1, thereby inhibiting MEOX1 expression and activity. In summary, our findings pinpointed MEOX1 as a cell-specific and clinically translatable target in fibrosis. Moreover, we demonstrated the potent anti-fibrotic effect of AIL in pulmonary fibrosis, specifically through the suppression of JUN-dependent MEOX1 activation.

407 The OGT/O-GlcNAc Axis Regulates Fibrosis Resolution in Idiopathic Pulmonary Fibrosis

OBJECTIVES/GOALS: Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease characterized by dysregulated collagen accumulation in the lung parenchyma. Our goal is to investigate the role of O-linked N-Acetylglucosamine (O-GlcNAc) transferase (OGT) in pulmonary fibrosis to ultimately discover novel therapies for fibrosis resolution. METHODS/STUDY POPULATION: Lung tissue from IPF and non-IPF donors was subjected to immunohistochemistry (IHC) to assess O-GlcNAc levels. Primary human lung fibroblasts were treated with OGT or O-GlcNAcase (OGA) inhibitors followed by transforming growth factor-beta 1 (TGF-β1) stimulation to assess O-GlcNAc regulation of fibroblast-to-myofibroblast transition (FMT) markers [alpha smooth muscle actin (α-SMA) and type 1 and type 3 collagen (COL1α1, COL3α1)] In Drosophila melanogaster, OGT knockdown (KD)/overexpression (OE) was conditionally induced to assess pericardin, a type IV collagen-like protein, regulation by immunofluorescence. Lastly, a mouse model of bleomycin-induced pulmonary fibrosis was examined following OGT KD and assessed for fibrosis resolution via histology, hydroxyproline assay, and western blotting. RESULTS/ANTICIPATED RESULTS: O-GlcNAc staining was increased in IPF lung tissue compared to non-IPF control lungs. In primary human lung fibroblasts, TGF-α1 administration resulted in increased FMT markers (α-SMA, COL1α1, and COL3α1), which were reduced or increased by OGT or OGA inhibition, respectively. Genetic manipulation in the Drosophila models showed decreased pericardin expression with OGT KD compared to the wild-type, whereas OGT OE increased pericardin compared to control. Additionally, OGT KD in bleomycin treated aged mice resulted in reduced collagen levels at the transcript and protein level and concurrent fibrosis resolution as assessed by Masson’s trichrome staining and total hydroxyproline analysis. Collectively, showing OGT/O-GlcNAc regulating collagen in fibrosis resolution. DISCUSSION/SIGNIFICANCE: These data suggest that the OGT/O-GlcNAc axis regulates collagen deposition in pulmonary fibrosis, and we show that O-GlcNAc is implicated in the pathogenesis of IPF. We identified OGT as a therapeutic target to overcome current drug limitations, opening new horizons for biomedical treatment.

Antrodia cinnamomea extract alleviates bleomycin-induced pulmonary fibrosis in mice by inhibiting the mTOR pathway

BackgroundPulmonary fibrosis is a progressive diffuse parenchymal lung disorder with a high mortality rate. Studies have indicated that injured lung tissues release various pro-inflammatory factors, and produce a large amount of nitric oxide. There is also accumulation of collagen and oxidative stress-induced injury, collectively leading to pulmonary fibrosis. Antrodia cinnamomea is an endemic fungal growth in Taiwan, and its fermented extracts exert anti-inflammatory effects to alleviate liver damages. Hence, we hypothesized and tested the feasibility of using A. cinnamomea extracts for treatment of pulmonary fibrosis. MethodsThe TGF-β1-induced human lung fibroblast cells (MRC-5) in vitro cell assay were used to evaluate the effects of A. cinnamomea extracts on the collagen production in MRC-5. Eight-week-old ICR mice were intratracheally administered bleomycin and then fed with an A. cinnamomea extract on day 3 post-administration of bleomycin. At day 21 post-bleomycin administration, the pulmonary functional test, the expression level of inflammation- and fibrosis-related genes in the lung tissue, and the histopathological change were examined. ResultsThe A. cinnamomea extract significantly attenuated the expression level of collagen in the TGF-β1-induced MRC-5 cells. In the A. cinnamome-treated bleomycin-induced lung fibrotic mice, the bodyweight increased, pulmonary functions improved, the lung tissues expression level of inflammatory factor and the fibrotic indicator were decreased, and the histopathological results showed the reduction of thickening of the inter-alveolar septa. ConclusionsThe Antrodia cinnamomea extract significant protects mice against bleomycin-induced lung injuries through improvement of body weight gain and lung functions, and attenuation of expression of inflammatory and fibrotic indicators.

IL20Rb aggravates pulmonary fibrosis through enhancing bone marrow derived profibrotic macrophage activation

Idiopathic pulmonary fibrosis (IPF) is one of the most fatal chronic interstitial lung diseases with unknown pathogenesis, current treatments cannot truly reverse the progression of the disease. Pulmonary macrophages, especially bone marrow derived pro-fibrotic macrophages, secrete multiple kinds of profibrotic mediators (SPP1, CD206, CD163, IL-10, CCL18…), thus further promote myofibroblast activation and fibrosis procession. IL20Rb is a cell-surface receptor that belongs to IL-20 family. The role of IL20Rb in macrophage activation and pulmonary fibrosis remains unclear. In this study, we established a bleomycin-induced pulmonary fibrosis model, used IL4/13-inducing THP1 cells to induce profibrotic macrophage (M2-like phenotype) polarization models. We found that IL20Rb is upregulated in the progression of pulmonary fibrosis, and its absence can alleviate the progression of pulmonary fibrosis. In addition, we demonstrated that IL20Rb promote the activation of bone marrow derived profibrotic macrophages by regulating the Jak2/Stat3 and Pi3k/Akt signaling pathways. In terms of therapeutic strategy, we used IL20Rb neutralizing antibodies for animal administration, which was found to alleviate the progression of IPF. Our results suggest that IL20Rb plays a profibrotic role by promoting profibrotic macrophage polarization, and IL20Rb may become a potential therapeutic target for IPF. Neutralizing antibodies against IL20Rb may become a potential drug for the clinical treatment of IPF.

Pazopanib attenuated bleomycin-induced pulmonary fibrosis via suppressing TGF-β1 signaling pathway.

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease with a high mortality rate and limited treatment efficacy. Nintedanib, a tyrosine kinase inhibitor, is clinically used to treat pulmonary fibrosis. At present, only nintedanib is on the market for the treatment of pulmonary fibrosis. Pazopanib is a drug for the treatment of renal cell carcinoma and advanced soft tissue sarcoma. In this study, we explored whether pazopanib can attenuate bleomycin (BLM)-induced pulmonary fibrosis and explored its antifibrotic mechanism. In vivo and in vitro investigations were carried out to investigate the efficacy and mechanism of action of pazopanib in pulmonary fibrosis. In vivo experiments showed that pazopanib can alleviate pulmonary fibrosis caused by BLM, reduce the degree of collagen deposition and improve lung function. In vitro experiments showed that pazopanib suppressed transforming growth factor-β1 (TGF-β1)-induced myofibroblast activation and promoted apoptosis and autophagy in myofibroblasts. Further mechanistic studies demonstrated that pazopanib inhibited the TGF-β1/Smad and non-Smad signaling pathways during fibroblast activation. In conclusion, pazopanib attenuated BLM-induced pulmonary fibrosis by suppressing the TGF-β1 signaling pathway. Pazopanib inhibits myofibroblast activation, migration, autophagy, apoptosis, and extracellular matrix (ECM) buildup by downregulating the TGF-β1/Smad signal route and the TGF-β1/non-Smad signal pathway. It has the same target as nintedanib and is a tyrosine kinase inhibitor.

Curculigoside Attenuates Endoplasmic Reticulum Stress-Induced Epithelial Cell and Fibroblast Senescence by Regulating the SIRT1-P300 Signaling Pathway.

The senescence of alveolar epithelial cells (AECs) and fibroblasts plays a pivotal role in the pathogenesis of idiopathic pulmonary fibrosis (IPF), a condition lacking specific therapeutic interventions. Curculigoside (CCG), a prominent bioactive constituent of Curculigo, exhibits anti-osteoporotic and antioxidant activities. Our investigation aimed to elucidate the anti-senescence and anti-fibrotic effects of CCG in experimental pulmonary fibrosis and delineate its underlying molecular mechanisms. Our findings demonstrate that CCG attenuates bleomycin-induced pulmonary fibrosis and lung senescence in murine models, concomitantly ameliorating lung function impairment. Immunofluorescence staining for senescence marker p21, alongside SPC or α-SMA, suggested that CCG's mitigation of lung senescence correlates closely with the deceleration of senescence in AECs and fibroblasts. In vitro, CCG mitigated H2O2-induced senescence in AECs and the natural senescence of primary mouse fibroblasts. Mechanistically, CCG can upregulate SIRT1 expression, downregulating P300 expression, enhancing Trim72 expression to facilitate P300 ubiquitination and degradation, reducing the acetylation levels of antioxidant enzymes, and upregulating their expression levels. These actions collectively inhibited endoplasmic reticulum stress (ERS) and alleviated senescence. Furthermore, the anti-senescence effects and mechanisms of CCG were validated in a D-galactose (D-gal)-induced progeroid model. This study provides novel insights into the mechanisms underlying the action of CCG in cellular senescence and chronic diseases, offering potential avenues for the development of innovative drugs or therapeutic strategies.

Study on miRNA expression and regulatory network of Amygdalus mongolica oil and amygdalin in the treatment of pulmonary fibrosis

IntroductionAmygdalus mongolica (Maxim.) Ricker is a traditional Chinese medicine known for its ability to relieve cough and expectorate phlegm and is commonly used to treat dry throat, dry cough, and bronchitis. A. mongolica oil and amygdalin were the active components isolated from the seed kernel seeds of A. mongolica. The main objective of this study was to investigate the effects of A. mongolica oil and amygdalin on bleomycin-induced pulmonary fibrosis (PF) in rats by integrating pharmacodynamic, transcriptomics, and bioinformatics, to determine the changes of miRNAs in both against PF, and to explore the underlying mechanisms. MethodsA rat model of PF was induced by administering bleomycin through the trachea. The rats were randomized into several groups: a control group (CON), an untreated model group (MOD), an active control group treated with pirfenidone (PFD), and groups receiving different doses of A. mongolica oil (5 g/kg [OIL-L], 10 g/kg [OIL-M], and 15 g/kg [OIL-H]), or amygdalin (20 mg/kg [AMY-L], 40 mg/kg [AMY-M], and 80 mg/kg [AMY-H]). After 28 days, samples were collected for subsequent pharmacodynamic and transcriptomic analyses. ResultsThe results demonstrated that A. mongolica oil and amygdalin effectively reduced the abnormally elevated levels of IL-1β, IL-6, HA, LN and COL-IV in PF rats and alleviated bleomycin-induced pulmonary fibrotic changes. Furthermore, compared to the MOD group, the expression levels of 27 miRNAs were up-regulated and 23 miRNAs were down-regulated in the OIL 10 g/kg group. Among the up-regulated miRNAs, two novel differentially expressed miRNAs (DE-miRNAs) were identified. In the AMY 20 mg/kg group, 12 miRNAs were up-regulated and 10 were down-regulated when compared to the MOD group. These DE-miRNAs were found to be enriched in pathways such as the PI3K-Akt signalling pathway, MAPK signalling pathway, and calcium signalling pathway. The microRNAs miR-301b-3p, miR-667-5p, miR-363-3p, and miR-540-3p may be associated with both the anti-PF mechanism of A. mongolica oil and the anti-PF mechanism of amygdalin. DiscussionNumerous studies have demonstrated the significance of various pathways, including PI3K-Akt, MAPK, and calcium signalling pathways, in the mechanism of PF and the development of anti-PF medications. Meanwhile, multiple miRNAs, including miR-301b-3p, miR-667-5p, miR-363-3p, and miR-540-3p, have been found to be associated with lung disease and fibrosis. ConclusionsThe present experiments confirmed the effectiveness of A. mongolica oil and amygdalin in reducing inflammation and fibrosis in bleomycin-induced PF rats, with particularly favorable outcomes observed in the A. mongolica oil 10 g/kg versus amygdalin 20 mg/kg. Meanwhile, miRNAs miR-301b-3p, miR-667-5p, miR-363-3p and miR-540-3p were found to be potentially associated with both A. mongolica oil and amygdalin anti-PF mechanisms. Based on our findings, we suggest that these miRNAs might play key roles in the anti-PF mechanism of A. mongolica. The individual miRNAs require further investigation.