Idiopathic Pulmonary Fibrosis Research Articles

Deciphering the Underlying Mechanisms of Sanleng-Ezhu for the Treatment of Idiopathic Pulmonary Fibrosis Based on Network Pharmacology and Single-cell RNA Sequencing Data.

To decipher the underlying mechanisms of Sanleng-Ezhu for the treatment of idiopathic pulmonary fibrosis based on network pharmacology and single-cell RNA sequencing data. Idiopathic Pulmonary Fibrosis (IPF) is the most common type of interstitial lung disease. Although the combination of herbs Sanleng (SL) and Ezhu (EZ) has shown reliable efficacy in the management of IPF, its underlying mechanisms remain unknown. Based on LC-MS/MS analysis and the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database, we identified the bioactive components of SL-EZ. After obtaining the IPF-related dataset GSE53845 from the Gene Expression Omnibus (GEO) database, we performed the differential expression analysis and the weighted gene co-expression network analysis (WGCNA), respectively. We obtained lowly and highly expressed IPF subtype gene sets by comparing Differentially Expressed Genes (DEGs) with the most significantly negatively and positively related IPF modules in WGCNA. Subsequently, we performed Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on IPF subtype gene sets. The low- and highexpression MCODE subgroup feature genes were identified by the MCODE plug-in and were adopted for Disease Ontology (DO), GO, and KEGG enrichment analyses. Next, we performed the immune cell infiltration analysis of the MCODE subgroup feature genes. Single-cell RNA sequencing analysis demonstrated the cell types which expressed different MCODE subgroup feature genes. Molecular docking and animal experiments validated the effectiveness of SL-EZ in delaying the progression of pulmonary fibrosis. We obtained 5 bioactive components of SL-EZ as well as their corresponding 66 candidate targets. After normalizing the samples of the GSE53845 dataset from the GEO database source, we obtained 1907 DEGs of IPF. Next, we performed a WGCNA analysis on the dataset and got 11 modules. Notably, we obtained 2 IPF subgroups by contrasting the most significantly up- and down-regulated modular genes in IPF with DEGs, respectively. The different IPF subgroups were compared with drugcandidate targets to obtain direct targets of action. After constructing the protein interaction networks between IPF subgroup genes and drug candidate targets, we applied the MCODE plug-in to filter the highest-scoring MCODE components. DO, GO, and KEGG enrichment analyses were applied to drug targets, IPF subgroup genes, and MCODE component signature genes. In addition, we downloaded the single-cell dataset GSE157376 from the GEO database. By performing quality control and dimensionality reduction, we clustered the scattered primary sample cells into 11 clusters and annotated them into 2 cell subtypes. Drug sensitivity analysis suggested that SL-EZ acts on different cell subtypes in IPF subgroups. Molecular docking revealed the mode of interaction between targets and their corresponding components. Animal experiments confirmed the efficacy of SL-EZ. We found SL-EZ acted on epithelial cells mainly through the calcium signaling pathway in the lowly-expressed IPF subtype, while in the highly-expressed IPF subtype, SL-EZ acted on smooth muscle cells mainly through the viral infection, apoptosis, and p53 signaling pathway.

Protection of Qingfei Xieding prescription from idiopathic pulmonary fibrosis by regulating renin-angiotensin and ferroptosis in MLE-12 cells.

Idiopathic pulmonary fibrosis (IPF) is a lifelong lung disease, but there is no specific drug for treatment. Qingfei Xieding prescription (QF) is active in the treatment of lung diseases. More comprehensive mechanisms over how QF exhibits anti-pulmonary fibrosis need to be elucidated. TGF-β was used to construct a pulmonary fibrosis cell model in vitro. Bleomycin was applied to induce a lung tissue fibrosis model in mice in vivo. Flow cytometry was used to detect cellular ROS and lipid oxidation levels. Cell substructure was observed by Transmission Electron Microscopy. ELISA was used to determine the levels of inflammatory factors. HE staining, Masson staining and immunohistochemistry were performed to evaluate the degree of fibrosis. Western Blot assay was used to determine the protein expressions of different molecules. In TGF-β-exposed lung epithelial MLE-12 cell model, α-SMA and Collagen I were significantly elevated and cell viability was reduced. QF treatment restored the cell viability decreased by exogenous TGF-β. Ferroptosis inducer Erastin administration could reverse the beneficial effects such as lipid oxidation and ROS reduction caused by QF treatment. QF was proven to inhibit ferroptosis and alleviated the process of IPF by activating ACE2 signal axis. In bleomycin induced IPF mice model, QF altered lung coefficient, body weight and the expression of inflammatory factors, which were prevented by ferroptosis activator Erastin. QF was demonstrated to affect the ACE2-ERK signaling axis in vivo. QF alleviated idiopathic pulmonary fibrosis by regulating renin-angiotensin through blocking ferroptosis. This research offers evidence for the potentiality of QF in clinical application for IPF therapy.

"Lipid Nanoparticles for Pulmonary Fibrosis: A Comprehensive Review".

Idiopathic pulmonary fibrosis (IPF) is a fatal progressive and irreversible ailment associated with the proliferation of fibroblast and accumulation of extracellular matrix (ECM) with gradual scarring of lung tissue. Despite several research studies, the treatments available are not efficient enough for the reversal of the disease and are constantly in progress. No drugs other than Pirfenidone and Nintedanib have been approved for the treatment of IPF, necessitating the exploration of novel therapeutic strategies. Recently, lipid-based nanoparticles (LNPs) have drawn more attention because of their potential to enhance the solubility of drugs, cross biological barriers of the lungs and specifically target lung fibrotic tissues, overcoming various challenges in treating IPF. LNPs offer a versatile platform to encapsulate a wide range of drugs, both hydrophilic and lipophilic, improving their bioavailability, allowing sustained release and reducing toxicity, which radiates their significant role in addressing the complexities of IPF. This review summarizes the pathogenesis and conventional treatment of idiopathic pulmonary fibrosis, along with their drawbacks. The review focuses on different types of lipid-based nanoparticles that have been tested in the treatment of idiopathic pulmonary fibrosis, including nanoemulsions, liposomes, solid lipid nanoparticles, nanostructured lipid carriers, niosomes and lipid-polymer hybrid nanoparticles. The review also highlights the future prospects that can offer a potential approach for developing novel strategies to treat idiopathic pulmonary fibrosis.

Yohimbine treatment improves pulmonary fibrosis by attenuating the inflammation and oxidative stress via modulating the MAPK pathway

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disorder characterized by the accumulation of extracellular matrix and collagen, resulting in significant parenchymal scarring and respiratory failure that leads to mortality. Yohimbine (YBH) is an α-2 adrenergic receptor antagonist with anti-oxidant and anti-inflammatory properties. In the current study, we aimed to investigate the anti-inflammatory, anti-oxidant and anti-fibrotic activity of YBH against LPS/TGF-β-induced differentiation in BEAS-2B/LL29 cells and bleomycin (BLMN) induced pulmonary fibrosis model in rats. Network pharmacology, gene expression, Western-blot analysis, immune-cytochemistry/immunohistochemistry, lung function and histology techniques were used to assess the fibrotic marker expression/levels in cells or rat lung tissues. YBH treatment significantly attenuated the LPS-induced pro-inflammatory (identified through a network-pharmacology approach) and oxidative stress markers expression in lung epithelial cells. TGF-β stimulation significantly elevated the fibrotic cascade of markers and treatment with YBH attenuated these markers’ expression/levels. Intra-tracheal administration of BLMN caused a significant elevation of various inflammatory/oxidative stress and fibrotic markers expression in lung tissues and treatment with YBH significantly mitigated the same. Ashcroft score analysis revealed that BLMN exhibited severe distortion of the lungs, elevation of thickness of the alveolar walls and accumulation of collagen in tissues, further treatment with YBH significantly suppressed these events and improved the lung architecture. Lung functional parameters demonstrated that BLMN-induced stiffness and resistance were reduced considerably upon YBH treatment and restored lung function dose-dependently. Overall, this study reveals that YBH treatment significantly attenuated the BLMN-induced fibrosis by regulating the MAPK pathway and provided insightful information for progressing towards translational outcomes.

Differences Between Patients with Probable UIP and Definite UIP on HRCT in Idiopathic Pulmonary Fibrosis: A Real-World Cohort Study

Background: Both a probable usual interstitial pneumonia (UIP) pattern (p-UIP) and a definite UIP pattern (d-UIP) on high-resolution computed tomography (HRCT) are sufficient to establish a diagnosis of idiopathic pulmonary fibrosis (IPF) without the need for a surgical lung biopsy, according to the 2022 IPF guidelines. However, it remains unknown whether patients with p-UIP and d-UIP have similar disease behaviors and clinical courses. Material and Methods: We retrospectively collected clinical data of patients with IPF and divided the patients into two groups according to their HRCT patterns: a p-UIP group and a d-UIP group. The baseline characteristics, survival rates, and pulmonary function tests were compared between the two groups. The risk factors for mortality were determined by Cox regression in p-UIP and d-UIP separately. Results: There were 304 patients in the p-UIP group and 480 patients in the d-UIP group. Patients in the d-UIP group were more likely to have smoking histories (p < 0.001) and had lower baseline FVC% (74% vs. 77%, p = 0.021) and DLCO% (50% vs. 58%, p < 0.001). Survival rates were higher in p-UIP compared with d-UIP (p = 0.004). There were no differences in changes in FVC% or DLCO% between the two groups. Baseline DLCO% was the only independent risk factor for mortality in p-UIP. Baseline FVC% was independently associated with mortality in d-UIP. Symptom of cough was a risk factor for disease progression (OR = 1.2, p = 0.002) in p-UIP, while symptom of dyspnea might be associated with disease progression in d-UIP (OR = 2.7, p = 0.065). Male patients (OR = 1.88, p = 0.002) with a smoking history (OR = 1.16, p = 0.002) were at higher risk of developing d-UIP. Conclusions: We observed the different disease trajectories between p-UIP and d-UIP. P-UIP on HRCT might identify a subgroup of IPF patients who are in the early stage with a better prognosis.

Acute exacerbation of progressive pulmonary fibrosis: incidence and outcomes.

Few data are available on acute exacerbation (AE) in patients with progressive pulmonary fibrosis (PPF) besides idiopathic pulmonary fibrosis (IPF). This study aimed to investigate the AE incidence and outcomes among patients with PPF. Clinical data of patients with PPF (n = 133) were retrospectively collected at a single center. PPF was defined based on the criteria used in the INBUILD trial. AE was defined as a worsening of dyspnea typically within 30 days with new bilateral lung infiltration and no evidence of cardiac failure or fluid overload. Among patients with PPF, the mean age was 60.6 years old, 57.1% were females, and the most common etiology was connective tissue disease-related ILDs (63%). During the follow-up (median: 38.0 months) after PPF diagnosis, 42 patients (31.6%) experienced AE. The 1-, 3-, and 5-year AE incidences were 12.5%, 30.3%, and 38.0%, respectively. Older age, rheumatoid arthritis associated ILD, fibrotic hypersensitivity pneumonitis, and lower lung diffusing capacity for carbon monoxide were AE risk factors. Patients with AE demonstrated worse survival (median survival: 30 months vs. not reached; p < 0.001) after PPF diagnosis than those without. AE was independently associated with mortality in patients with PPF (hazard ratio [HR], 2.194; 95% confidence interval [CI], 1.285-3.747; p = 0.004) in the multivariable Cox analysis, along with older age, lower lung diffusing capacity for carbon monoxide, and the usual interstitial pneumonia-like pattern on high-resolution computed tomography. Our results suggest AE is not uncommon and significantly impacts on survival in patients with PPF.

Co-culture of human AT2 cells with fibroblasts reveals a MUC5B phenotype: insights from an organoid model

Impaired interaction of fibroblasts with pneumocytes contributes to the progression of chronic lung disease such as idiopathic pulmonary fibrosis (IPF). Mucin 5B (MUC5B) is associated with IPF. Here we analyzed the interaction of primary fibroblasts and alveolar type 2 (AT2) pneumocytes in the organoid model. Single-cell analysis, histology, and qRT-PCR revealed that fibroblasts expressing high levels of fibrosis markers regulate STAT3 signaling in AT2 cells, which is accompanied by cystic organoid growth and MUC5B expression. Cystic growth and MUC5B expression were also caused by the cytokine IL-6. The PI3K-Akt signaling pathway was activated in fibroblasts. The drug dasatinib prevented the formation of MUC5B-expressing cystic organoids. MUC5B associated with AT2 cells in samples obtained from IPF patients. Our model shows that fibrotic primary fibroblasts induce impaired differentiation of AT2 cells via STAT3 signaling pathways, as observed in IPF patients. It can be used for mechanistic studies and drug development.

Inhaled exogenous thymosin beta 4 suppresses bleomycin-induced pulmonary fibrosis in mice via TGF-β1 signalling pathway.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fibrotic interstitial lung disease. The two drugs indicated for IPF have limited efficacy and there is an urgent need to develop new drugs. Thymosin β4 (Tβ4) is a natural endogenous repair factor whose antifibrotic effects have been reported. This study aimed to evaluate the effect of exogenous recombinant human thymosin beta 4 (rhTβ4) on pulmonary fibrosis. Pulmonary fibrosis was induced in mice with bleomycin, and rhTβ4 was administrated by nebulization following three strategies: early dosing, mid-term dosing, and late dosing. The rhTβ4 efficacy was assessed by hydroxyproline, lung function, and lung histopathology. In vitro, the effects of rhTβ4 on fibroblast and lung epithelial cell phenotypes, as well as the TGF-β1 pathway, were evaluated. Aerosol administration of rhTβ4 could alleviate bleomycin-induced pulmonary fibrosis in mice at different stages of fibrosis. Studies conducted in vitro suggested that rhTβ4 could suppress lung fibroblasts from proliferating, migrating, and activation via regulating the TGF-β1 signalling pathway. In vitro, rhTβ4 also inhibited the epithelial-mesenchymal transition-like process of pulmonary epithelial cells. This study suggests that nebulized rhTβ4 is a potential treatment for IPF.

Ficolin-1 ameliorates pulmonary fibrosis via directly binding to TGF-β1

BackgroundFicolins were originally identified as proteins that bind to transforming growth factor-β1 (TGF-β1). They are capable of activating the complement system through lectin pathway for immune system protection. Ficolin-2 and 3 have been identified in patients with interstitial lung diseases (ILD) and their function in these diseases is currently being explored. In contrast, the functional role of ficolin-1 in pulmonary fibrosis is still elusive and remains to be elucidated.MethodsThe expression of ficolin-1 in the plasma of idiopathic pulmonary fibrosis (IPF) and connective tissue disease (CTD)-ILD patients was first determined. As the orthologue of human ficolin-1, ficolin-B knockout and ficolin-B overexpression were used to establish bleomycin (BLM)-induced pulmonary fibrosis mouse model. Co-immunoprecipitation, immunofluorescence and RNA sequencing were utilized to explore and expound on the expression and the functional mechanism of ficolin-1 in pulmonary fibrosis.ResultsCompared with healthy controls, plasma ficolin-1 was significantly decreased in patients with IPF and CTD-ILD. In the bleomycin (BLM)-induced mice model, ficolin-B deficiency aggravated lung injury and fibrosis. There was also observed increase in TGF-β1 levels and enhanced downstream signaling. However, the overexpression of ficolin-B showed preventative and therapeutic efficacy against lung fibrosis. Furthermore, coimmunoprecipitation studies revealed the direct interaction between ficolin-1 and TGF-β1 in human plasma, which was further confirmed by the colocalization of ficolin-1 and TGF-β1 in lung tissues.ConclusionsFicolin-1 inhibits pulmonary fibrosis by directly binding to the key profibrogenic factor TGF-β1, marking it as a potential target for therapy in the treatment of fibrotic lung diseases.

A Ramped Treadmlll Protocol Exercise Test Identifies Higher Ambulatory Oxygen Needs in IPF and COPD.

In the United States (U.S.), ambulatory oxygen is recommended for patients with idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) who experience symptomatic exertional hypoxemia. Ambulatory oxygen need is often determined by submaximal hall walk testing; however, this may fail to accurately characterize exertional hypoxemia in some patients. Assess for differences in ambulatory oxygen needs between IPF and COPD patients who completed a ramped treadmill protocol exercise test (RTPET) and correlate oxygen flow rates determined at highest level exertion with lung function and exercise parameters. Oxygen "need" is defined as flow rate needed to maintain oxygen saturation >90% in patients who desaturate to <88%. We conducted a retrospective review of RTPET results for IPF and COPD patients who also recently completed spirometry. The RTPET has three phases: rest, submaximal usual pace walking at 0% treadmill grade for 3 minutes, and highest level walking at the UP walk speed with increasing treadmill grade by 2% every 2 minutes. IPF patients were part of a clinical registry while COPD patients were identified based on diagnosis coding and spirometry (FEV1/FVC <0.70). The RTPET for both groups was completed based on a pulmonologist's referral. We included 329 IPF and 2,343 COPD patients. A greater proportion of IPF patients required ambulatory oxygen to maintain saturation >90%. After adjusting for demographic covariates and exercise parameters, IPF patients required higher ambulatory oxygen flow rates compared to COPD subjects with similar DLCO values. Of patients who did not require oxygen with submaximal usual pace testing, 49% with IPF and 24% with COPD required oxygen at highest level exertion. The RTPET identified higher oxygen flow needs at highest level exertion in IPF versus COPD patients; however, in both diseases, there was a significant proportion of patients who were only found to have exertional desaturation at highest level exertion. Current oxygen policies and reliance on submaximal testing may fail to meet the needs of patients with IPF and COPD. Further studies are needed to determine if oxygen prescriptions targeting highest level desaturation improve clinical outcomes, symptoms, or quality-of-life.

Triangle correlations of lung microbiome, host physiology and gut microbiome in a rat model of idiopathic pulmonary fibrosis

Changes in lung and gut microbial communities have been associated with idiopathic pulmonary fibrosis (IPF). This study aimed to investigate correlations between microbial changes in the lung and gut and host physiological indices in an IPF model, exploring potential mechanisms of the lung-gut axis in IPF pathogenesis. IPF model rats were established via trans-tracheal injection of bleomycin, with assessments of hematological indices, serum cytokines, lung histopathology, and microbiome alterations. Significant differences in microbial structure and composition were observed in the IPF model compared to controls, with 14 lung and 7 gut microbial genera showing significant abundance changes. Further analysis revealed 20 significant correlations between pulmonary and gut genera. Notably, 11 pairs of correlated genera were linked to the same IPF-related physiological indices, such as hydroxyproline, mean corpuscular volume (MCV), and red cell distribution width-standard deviation (RDW-SD). We identified 24 instances where a lung and a gut genus were each associated with the same physiological index, forming "lung genus—index—gut genus" relationships. Mediation analysis showed that indices like hydroxyproline, MCV, and RDW-SD mediated correlations between 10 lung genera (e.g., Cetobacterium, Clostridium XVIII ) and the gut genus Allobaculum. This study first describes gut-lung microbial interactions in pulmonary fibrosis. Mediation analysis suggests pathways underlying "lung genus—host index—gut genus" and "gut genus—host index—lung genus" correlations, thus providing clues to further elucidate the mechanisms of the “gut-lung axis” in IPF pathogenesis.

Quantification of Interstitial Lung Diseases, From the AJR Special Series on Quantitative Imaging.

High-resolution CT (HRCT) plays an important role in diagnosing and monitoring interstitial lung diseases (ILDs). Despite advances, predicting disease progression and treatment response remains challenging. HRCT enables noninvasive visualization and classification of patterns of lung injury and assessment of disease extent. Visual estimation of CT extent of fibrotic lung disease is an independent predictor of mortality and progression, but is subjective, with only modest interobserver agreement for radiologic interpretation of ILD. Machine learning-based textural analysis of fibrosis extent on baseline and serial HRCT scans shows robust correlations with physiologic measures and strong association with risk of disease progression or mortality across various fibrosing ILDs. In idiopathic pulmonary fibrosis, quantitative CT (QCT) assessment is associated with physiologic impairment and risk of progression and death, and increasing severity of fibrosis on longitudinal evaluation is associated with increased risk of progression and death. Similar results have been noted for fibrotic hypersensitivity pneumonitis and connective tissue disease. This review focuses on QCT techniques for ILDs. We describe the clinical need for quantification of lung disease and illustrate the role of conventional visual evaluation and of QCT approaches in defining disease severity, prognosis, and longitudinal progression, both in established disease and in preclinical interstitial abnormality.

Perioperative Anti-Fibrotic Treatment Prevents Acute Exacerbation of Idiopathic Pulmonary Fibrosis After Lung Cancer Surgery.

The surgical treatment of concomitant lung cancer in patients with idiopathic pulmonary fibrosis is challenging due to the risk of life-threatening complications such as acute exacerbation development in the perioperative period. Few studies have investigated the role of anti-fibrotic drugs in this setting. The aim of this multicenter retrospective study was to evaluate the incidence of acute exacerbation, according to Collard, after lung resection in patients affected by concomitant idiopathic pulmonary fibrosis and lung cancer who were or were not on antifibrotic treatment. Secondary outcomes included: 30 and 90-day mortality and an estimation of overall and disease-free survival. The study population consisted of patients affected by idiopathic pulmonary fibrosis who received curative-intent lung surgery in three Italian academic centers between 2015 and 2022. Patients were divided into two groups based on whether they were on perioperative treatment with anti-fibrotic drugs (chronical or prophylactic use) or not. To define predictors of acute exacerbation, univariate and multivariable exact logistic regression analysis were performed. The Kaplan-Meier method with log-rank test was used to estimate survival. During the study period, n = 55 patients underwent lung resection for lung cancer, including 29 patients who were treated with antifibrotic agents. Although the sample size was small and few events were studied, the incidence of acute exacerbation was significantly lower among patient on anti-fibrotic therapy (3.4% vs. 23.1%, p = 0.044); in addition, anti-fibrotic treatment was the strong factor preventing acute exacerbation at the multivariable analysis (OR 0.089, p = 0.038). Post-operative 30- and 90-day mortality rates were not significantly lower in the anti-fibrotic treatment group (0% and 0% vs. 7.7% and 11.5%, p = 0.21 and p = 0.099, respectively). Overall and disease-free survival rates were similar. Considering the limitations of this retrospective study with a small sample size, anti-fibrotic perioperative treatment was associated with reduced incidence of acute exacerbation. Based on these real-world data, this pathway could be proposed as a prophylactic treatment in patients with concomitant idiopathic pulmonary fibrosis and cancer undergoing lung resection.

Allium sativum nanovesicles exhibit anti-inflammatory and antifibrotic activity in a bleomycin-induced lung fibrosis model.

Idiopathic pulmonary fibrosis (IPF) is a chronic and highly fatal disease characterized by excessive accumulation of extracellular matrix (ECM), foci of myofibroblasts, and a usual pattern of interstitial pneumonia. As suggested by international guidelines, the treatment for this disease involves supportive therapies, as there is currently no effective treatment. Plant-derived nanovesicles have emerged as a new treatment for various diseases and have been tested in cellular and murine models. This research aimed to test the use of Allium sativum nanovesicles (AS-NV) in a murine model of IPF induced by bleomycin. AS-NV reduced the amount of collagen and restored lung architecture in the mouse model. AS-NV was tested on human lung fibroblasts, which do not affect the viability of healthy cells. AS-NV treatment decreases the mRNA levels of genes related to fibrosis, inflammation, and ECM deposition (Mmp2,Timp-2,Vegf,Pcna,Col1a1,Tgf-β,α-Sma,IL-1β,and Hif1a) in bleomycin-induced idiopathic pulmonary fibrosis. This research highlights the anti-inflammatory and antifibrotic activity of AS-NV, which contributes to plant nanovesicle mechanisms in IPF; however, more AS-NV studies are needed to identify alternative treatments for idiopathic pulmonary fibrosis.

Identification of potential mechanisms of Schisandrin B in the treatment of idiopathic pulmonary fibrosis by integrating network pharmacology and experimental validation.

Idiopathic pulmonary fibrosis (IPF) is a worsening fibrotic condition characterized by a short survival rate and limited treatment options. This study evaluates the potential anti-fibrotic properties of Schisandrin B (Sch B) through network pharmacology and experimental validation. A mouse model of bleomycin-induced pulmonary fibrosis was established, and the modeled mice were treated with Sch B at three doses (20 mg/kg/day, 40 mg/kg/day, and 80 mg/kg/day). A fibrotic model was developed in NIH/3T3 cells by treating them with TGF-β (10 ng/mL) and administering Sch B at various concentrations (10, 20, and 40 µM). The results revealed that Sch B treatment delayed the development of bleomycin-induced pulmonary fibrosis and substantially decreased the transcription levels of collagen I and α-SMA in TGF-β-induced fibroblasts. Core targets were screened with protein-protein interaction network analysis, molecular complex detection (MCODE), and CytoHubba plugin. The application of Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, and molecular docking highlighted the significance of the HIF-1α signaling pathway in the potential mechanism of Sch B in IPF therapy. Western blot, PCR, and immunofluorescence were performed to validate the effects of Sch B on HIF-1α. In vivo and in vitro, Sch B administration reduced HIF-1α expression. These outcomes provide valuable insights into the potential mechanism by which Sch B delays IPF development, with HIF-1α potentially serving as a key target. However, further investigation is warranted to assess the safety and efficacy of Sch B in clinical settings.

Discovery of Selective PDE1 Inhibitors with Anti-pulmonary Fibrosis Effects by Targeting the Metal Pocket.

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease with no ideal drugs. Our previous research demonstrated that phosphodiesterase 1 (PDE1) could be a promising target for the treatment of IPF. However, only a few selective PDE1 inhibitors are available, and the mechanism of recognition between inhibitors and the PDE1 protein is not fully understood. This study carried out a step-by-step optimization of a dihydropyrimidine hit Z94555858. By targeting the metal pocket of PDE1, a lead compound 3f was obtained, exhibiting an IC50 value of 11 nM against PDE1, moderate selectivity over other PDEs, and significant anti-fibrotic effects in bleomycin-induced pulmonary fibrosis rats. The structure-activity relationship study aided by molecular docking revealed that forming halogen bonds with water in the metal pocket greatly enhanced the PDE1 inhibition, providing a novel strategy for further rational design of PDE1 inhibitors.

Combined therapy with pirfenidone and nintedanib counteracts fibrotic silicosis in mice.

Pneumoconiosis, especially silicosis, is a prevalent occupational disease with substantial global economic implications and lacks a definitive cure. Both pneumoconiosis and idiopathic pulmonary fibrosis (IPF) are interstitial lung diseases, which share many common physiological characteristics. Because pirfenidone and nintedanib are approved to treat IPF, their potential efficacy as antifibrotic agents in advanced silicosis deserves further exploration. Thus, we aimed to evaluate the individual and combined effects of pirfenidone and nintedanib in treating advanced silicosis mice and elucidate the underlying mechanisms of their therapeutic actions via multiomics. We administered monotherapy or combined therapy of pirfenidone and nintedanib, with low and high doses, in silicosis established after 6weeks and evaluated lung function, inflammatory responses and fibrotic status. Additionally, we employed transcriptomic and metabolomic analyses to uncover the mechanisms underlying different therapeutic strategies. Both pirfenidone and nintedanib were effective in treating advanced silicosis, with superior outcomes observed in combination therapy. Transcriptomic and metabolomic analyses revealed that pirfenidone and nintedanib primarily exerted their therapeutic effects by modulating immune responses, signalling cascades and metabolic processes involving lipids, nucleotides and carbohydrates. Furthermore, we experimentally validated both monotherapy and combined therapy yielded therapeutic benefits through two common signalling pathways: steroid biosynthesis and purine metabolism. In conclusion, pirfenidone and nintedanib, either individually or in combination, demonstrate substantial potential in advanced silicosis. Furthermore, combined therapy outperformed monotherapy, even at low doses. These therapeutic benefits are attributed to their influence on diverse signalling pathways and metabolic processes.

The Discovery of MORF-627, a Highly Selective Conformationally-Biased Zwitterionic Integrin αvβ6 Inhibitor for Fibrosis.

Inhibition of integrin αvβ6 is a promising approach to the treatment of fibrotic disease such as idiopathic pulmonary fibrosis. Screening a small library combining head groups that stabilize the bent-closed conformation of integrin αIIbβ3 with αv integrin binding motifs resulted in the identification of hit compounds that bind the bent-closed conformation of αvβ6. Crystal structures of these compounds bound to αvβ6 and related integrins revealed opportunities to increase potency and selectivity, and these efforts were accelerated using accurate free energy perturbation (FEP+) calculations. Optimization of PK parameters including permeability, bioavailability, clearance, and half-life resulted in the discovery of development candidate MORF-627, a highly selective inhibitor of αvβ6 that stabilizes the bent-closed conformation and has good oral PK. Unfortunately, the compound showed toxicity in a 28-day NHP safety study, precluding further development. Nevertheless, MORF-627 is a useful tool compound for studying the biology of integrin αvβ6.

Air Pollution and Interstitial Lung Disease.

This review article explores the multifaceted relationship between air pollution and interstitial lung diseases (ILDs), particularly focusing on idiopathic pulmonary fibrosis (IPF), the most severe form of fibrotic ILD. Air pollutants are mainly composed of particulate matter (PM), ozone (O3), nitrogen dioxide (NO2), carbon monoxide (CO), and sulfur dioxide (SO2). They are recognized as risk factors for several respiratory diseases. However, their specific effects on ILDs and related mechanisms have not been thoroughly studied yet. Emerging evidence suggests that air pollutants may contribute to the development and acute exacerbation of ILDs. Longitudinal studies have indicated that air pollution can adversely affect the prognosis of disease by decreasing lung function and increasing mortality. Lots of in vitro, in vivo, and epidemiologic studies have proposed possible mechanisms linking ILDs to air pollution, including inflammation and oxidative stress induced by exposure to air pollutants, which may induce mitochondrial dysfunction, promote cellular senescence, and disrupt normal epithelial repair processes. Despite these findings, effective interventions to mitigate effects of air pollution on ILD are not well established yet. This review emphasizes the urgent need to address air pollution as a key environmental risk factor for ILDs and calls for further studies to clarify its effects and develop preventive and therapeutic strategies.

CD206+ macrophages are relevant non-invasive imaging biomarkers and therapeutic targets in experimental lung fibrosis

BackgroundInterstitial lung diseases (ILDs) include a large number of diseases associated with progressive pulmonary fibrosis (PPF), including idiopathic pulmonary fibrosis (IPF). Despite the rarity of each of the fibrotic ILDs...