Idiopathic Pulmonary Fibrosis

Association study of human leukocyte antigen variants and idiopathic pulmonary fibrosis

Tue, 2024-02-20 06:00

ERJ Open Res. 2024 Feb 19;10(1):00553-2023. doi: 10.1183/23120541.00553-2023. eCollection 2024 Jan.

ABSTRACT

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF, and a prior association of the HLA-DQB1 gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Owing to the important role that the human leukocyte antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk.

METHODS: We performed a meta-analysis of associations of the HLA region with IPF risk in individuals of European ancestry from seven independent case-control studies of IPF (comprising 5159 cases and 27 459 controls, including a prior study of fibrotic interstitial pneumonia). Single nucleotide polymorphisms, classical HLA alleles and amino acids were analysed and signals meeting a region-wide association threshold of p<4.5×10-4 and a posterior probability of replication >90% were considered significant. We sought to replicate the previously reported HLA-DQB1 association in the subset of studies independent of the original report.

RESULTS: The meta-analysis of all seven studies identified four significant independent single nucleotide polymorphisms associated with IPF risk. However, none met the posterior probability for replication criterion. The HLA-DQB1 association was not replicated in the independent IPF studies.

CONCLUSION: Variation in the HLA region was not consistently associated with risk in studies of IPF. However, this does not preclude the possibility that other genomic regions linked to the immune response may be involved in the aetiology of IPF.

PMID:38375425 | PMC:PMC10875457 | DOI:10.1183/23120541.00553-2023

Categories: Literature Watch

SLC15A3 plays a crucial role in pulmonary fibrosis by regulating macrophage oxidative stress

Mon, 2024-02-19 06:00

Cell Death Differ. 2024 Feb 19. doi: 10.1038/s41418-024-01266-w. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a fatal and irreversible disease with few effective treatments. Alveolar macrophages (AMs) are involved in the development of IPF from the initial stages due to direct exposure to air and respond to external oxidative damage (a major inducement of pulmonary fibrosis). Oxidative stress in AMs plays an indispensable role in promoting fibrosis development. The oligopeptide histidine transporter SLC15A3, mainly expressed on the lysosomal membrane of macrophages and highly expressed in the lung, has proved to be involved in innate immune and antiviral signaling pathways. In this study, we demonstrated that during bleomycin (BLM)- or radiation-induced pulmonary fibrosis, the recruitment of macrophages induced an increase of SLC15A3 in the lung, and the deficiency of SLC15A3 protected mice from pulmonary fibrosis and maintained the homeostasis of the pulmonary microenvironment. Mechanistically, deficiency of SLC15A3 resisted oxidative stress in macrophages, and SLC15A3 interacted with the scaffold protein p62 to regulate its expression and phosphorylation activation, thereby regulating p62-nuclear factor erythroid 2-related factor 2 (NRF2) antioxidant stress pathway protein, which is related to the production of reactive oxygen species (ROS). Overall, our data provided a novel mechanism for targeting SLC15A3 to regulate oxidative stress in macrophages, supporting the therapeutic potential of inhibiting or silencing SLC15A3 for the precautions and treatment of pulmonary fibrosis.

PMID:38374230 | DOI:10.1038/s41418-024-01266-w

Categories: Literature Watch

The gene expression of CALD1, CDH2, and POSTN in fibroblast are related to idiopathic pulmonary fibrosis

Mon, 2024-02-19 06:00

Front Immunol. 2024 Feb 2;15:1275064. doi: 10.3389/fimmu.2024.1275064. eCollection 2024.

ABSTRACT

INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is characterized by progressive lung dysfunction due to excessive collagen production and tissue scarring. Despite recent advancements, the molecular mechanisms remain unclear.

METHODS: RNA sequencing identified 475 differentially expressed genes (DEGs) in the TGF-β1-induced primary lung fibrosis model. Gene expression chips GSE101286 and GSE110147 from NCBI gene expression omnibus (GEO) database were analyzed using GEO2R, revealing 94 DEGs in IPF lung tissue samples. The gene ontology (GO) and pathway enrichment, Protein-protein interaction (PPI) network construction, and Maximal Clique Centrality (MCC) scoring were performed. Experimental validation included RT-qPCR, Immunohistochemistry (IHC), and Western Blot, with siRNA used for gene knockdown. A co-expression network was constructed by GeneMANIA.

RESULTS: GO enrichment highlighted significant enrichment of DEGs in TGF-β cellular response, connective tissue development, extracellular matrix components, and signaling pathways such as the AGE-RAGE signaling pathway and ECM-receptor interaction. PPI network analysis identified hub genes, including FN1, COL1A1, POSTN, KIF11, and ECT2. CALD1 (Caldesmon 1), CDH2 (Cadherin 2), and POSTN (Periostin) were identified as dysregulated hub genes in both the RNA sequencing and GEO datasets. Validation experiments confirmed the upregulation of CALD1, CDH2, and POSTN in TGF-β1-treated fibroblasts and IPF lung tissue samples. IHC experiments probed tissue-level expression patterns of these three molecules. Knockdown of CALD1, CDH2, and POSTN attenuated the expression of fibrotic markers (collagen I and α-SMA) in response to TGF-β1 stimulation in primary fibroblasts. Co-expression analysis revealed interactions between hub genes and predicted genes involved in actin cytoskeleton regulation and cell-cell junction organization.

CONCLUSIONS: CALD1, CDH2, and POSTN, identified as potential contributors to pulmonary fibrosis, present promising therapeutic targets for IPF patients.

PMID:38370408 | PMC:PMC10869495 | DOI:10.3389/fimmu.2024.1275064

Categories: Literature Watch

Pirfenidone alleviates chronic pancreatitis via suppressing the activation of pancreatic stellate cells and the M1 polarization of macrophages

Sat, 2024-02-17 06:00

Int Immunopharmacol. 2024 Feb 16;130:111691. doi: 10.1016/j.intimp.2024.111691. Online ahead of print.

ABSTRACT

In the realm of fibroinflammatory conditions, chronic pancreatitis (CP) stands out as a particularly challenging ailment, lacking a dedicated, approved treatment. The potential of Pirfenidone (PFD), a drug originally used for treating idiopathic pulmonary fibrosis (IPF), in addressing CP's fibrotic aspects has sparked new interest. This investigation focused on the role of PFD in diminishing fibrosis and immune response in CP, using a mouse model induced by caerulein. The research extended to in vitro studies examining the influence of PFD on pancreatic stellate cells' (PSCs) behavior and the polarization of macrophages into M1 and M2 types. Advanced techniques like RNA sequencing and comprehensive data analyses were employed to decode the molecular interactions of PFD with PSCs. Supplementary experiments using techniques such as quantitative real-time PCR, western blotting, and immunofluorescence were also implemented. Results showed a notable reduction in pancreatic damage in PFD-treated mice, manifested through decreased acinar cell atrophy, lower collagen deposition, and a reduction in macrophage presence. Further investigation revealed PFD's capacity to hinder PSCs' migration, growth, and activation, alongside a reduction in the production and secretion of extracellular matrix proteins. This effect is primarily achieved by interfering with signaling pathways such as TGF-β/Smad, Wnt/β-catenin, and JAK/STAT. Additionally, PFD selectively hampers M1 macrophage polarization through the STAT3 pathway, without impacting M2 polarization. These outcomes highlight PFD's dual mechanism in moderating PSC activity and M1 macrophage polarization, positioning it as a promising candidate for CP therapy.

PMID:38367466 | DOI:10.1016/j.intimp.2024.111691

Categories: Literature Watch

Nintedanib plus Chemotherapy for Small Cell Lung Cancer with Comorbid Idiopathic Pulmonary Fibrosis

Fri, 2024-02-16 06:00

Ann Am Thorac Soc. 2024 Feb 16. doi: 10.1513/AnnalsATS.202311-941OC. Online ahead of print.

ABSTRACT

Rationale: A fatal acute exacerbation (AE) occasionally develops during chemotherapy for small-cell lung cancer (SCLC) with comorbid idiopathic pulmonary fibrosis (IPF). Objectives: This study aimed to assess the safety and efficacy of carboplatin, etoposide, and nintedanib combination therapy for unresectable SCLC with comorbid IPF. Methods: The NEXT-SHIP study is a multicenter, single-arm, phase 2 trial for unresectable SCLC with IPF (registry number: jRCTs031190119). The patients received carboplatin, etoposide, and nintedanib (150 mg BID). The primary endpoint was the incidence of IPF-AE at 28 days after last administration of cytotoxic chemotherapy, and the sample size was set at 33 (5.0% expected, 20.0% threshold). Measurements and Main Results: A total of 33 patients were registered; 87.9% were male, the median age was 73 years, the median %FVC was 85.2 %, and 51.5% had honeycomb lungs. The median observation period was 10.5 months. The incidence of IPF-AE at 28 days after last administration of cytotoxic chemotherapy was 3.0% (90% confidence interval [CI]: 0.2-13.6). The objective response rate was 68.8% (95% CI: 50.0-83.9). The median progression free survival and overall survival times were 4.2 months (95% CI: 4.2-5.5) and 13.4 months (95% CI 8.1-21.6), respectively. The most common adverse event ≥ grade 3 was neutropenia (81.8%), followed by leukopenia (39.4%) and thrombocytopenia (30.3%). Conclusions: This study met its primary endpoint regarding the incidence of IPF-AEs with promising results for efficacy. Carboplatin, etoposide, and nintedanib combination therapy may be one of the standard treatment options for SCLC with comorbid IPF. Clinical Trial Registration: jRCTs031190119.

PMID:38364204 | DOI:10.1513/AnnalsATS.202311-941OC

Categories: Literature Watch

A Test to Comprehensively Capture the Known Genetic Component of Familial Pulmonary Fibrosis

Fri, 2024-02-16 06:00

Am J Respir Cell Mol Biol. 2024 Feb 16. doi: 10.1165/rcmb.2024-0009MA. Online ahead of print.

ABSTRACT

The recent European Respiratory Society statement on familial pulmonary fibrosis (FPF) supports the need of genetic testing in the care of patients and their relatives. However, no solution (i.e., a concrete test) was provided to implemented genetic testing in daily practice. Herein, we tabulated and standardized the nomenclature of 128 genetic variants in 20 genes implicated in adult-onset pulmonary fibrosis. The objective was to develop a laboratory developed test (LDT) based on standard Sanger sequencing in order to capture all known FPF-associated variants. Targeted DNA fragments were amplified with harmonized PCR conditions to perform the LDT in a single 96-well plate. The new genetic test was evaluated in 62 sporadic cases of idiopathic pulmonary fibrosis (IPF). As expected in this population, we observed a low yield of disease-causing mutations. More importantly, 100% of targeted variants by the LDT were successfully evaluated. Furthermore, four variants of uncertain significance with in silico-predicted deleterious scores were identified in three patients, suggesting novel pathogenic variants in genes known to cause IPF. Finally, the MUC5B promoter variant rs35705950 was strongly enriched in these patients with a minor allele frequency of 41.1% compared to 10.6% in a matched population-based cohort (n=29,060), leading to an estimation that this variant may explain up to 35% of the population-attributable risk. This LDT provides a solution for rapid clinical translation. Technical laboratory details are provided so that specialised pulmonary centers can implement the LDT in-house in order to expedite the clinical recommendations of experts' panel.

PMID:38363828 | DOI:10.1165/rcmb.2024-0009MA

Categories: Literature Watch

e-Lung CT Biomarker Stratifies Patients at Risk of IPF Progression in a 52-Week Clinical Trial

Fri, 2024-02-16 06:00

Am J Respir Crit Care Med. 2024 Feb 16. doi: 10.1164/rccm.202312-2274LE. Online ahead of print.

NO ABSTRACT

PMID:38363798 | DOI:10.1164/rccm.202312-2274LE

Categories: Literature Watch

Qingfei Tongluo Mixture Attenuates Bleomycin-Induced Pulmonary Inflammation and Fibrosis through mTOR-Dependent Autophagy in Rats

Fri, 2024-02-16 06:00

Mediators Inflamm. 2024 Feb 8;2024:5573353. doi: 10.1155/2024/5573353. eCollection 2024.

ABSTRACT

As an interstitial fibrosis disease characterized by diffuse alveolitis and structural alveolar disorders, idiopathic pulmonary fibrosis (IPF) has high lethality but lacks limited therapeutic drugs. A hospital preparation used for the treatment of viral pneumonia, Qingfei Tongluo mixture (QFTL), is rumored to have protective effects against inflammatory and respiratory disease. This study aims to confirm whether it has a therapeutic effect on bleomycin-induced IPF in rats and to elucidate its mechanism of action. Male SD rats were randomly divided into the following groups: control, model, CQ + QFTL (84 mg/kg chloroquine (CQ) + 3.64 g/kg QFTL), QFTL-L, M, H (3.64, 7.28, and 14.56 g/kg, respectively) and pirfenidone (PFD 420 mg/kg). After induction modeling and drug intervention, blood samples and lung tissue were collected for further detection. Body weight and lung coefficient were examined, combined with hematoxylin and eosin (H&E) and Masson staining to observe lung tissue lesions. The enzyme-linked immunosorbent assay (ELISA) and the hydroxyproline (HYP) assay kit were used to detect changes in proinflammatory factors (transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β)) and HYP. Immunohistochemistry and Western blotting were performed to observe changes in proteins related to pulmonary fibrosis (α-smooth muscle actin (α-SMA) and matrix metalloproteinase 12 (MMP12)) and autophagy (P62 and mechanistic target of rapamycin (mTOR)). Treatment with QFTL significantly improved the adverse effects of bleomycin on body weight, lung coefficient, and pathological changes. Then, QFTL reduced bleomycin-induced increases in proinflammatory mediators and HYP. The expression changes of pulmonary fibrosis and autophagy marker proteins are attenuated by QFTL. Furthermore, the autophagy inhibitor CQ significantly reversed the downward trend in HYP levels and α-SMA protein expression, which QFTL improved in BLM-induced pulmonary fibrosis rats. In conclusion, QFTL could effectively attenuate bleomycin-induced inflammation and pulmonary fibrosis through mTOR-dependent autophagy in rats. Therefore, QFTL has the potential to be an alternative treatment for IPF in clinical practice.

PMID:38361765 | PMC:PMC10869187 | DOI:10.1155/2024/5573353

Categories: Literature Watch

Repositioning of ezetimibe for the treatment of idiopathic pulmonary fibrosis

Thu, 2024-02-15 06:00

Eur Respir J. 2024 Feb 15:2300580. doi: 10.1183/13993003.00580-2023. Online ahead of print.

ABSTRACT

We previously identified ezetimibe, an inhibitor of Niemann-Pick C1-like intracellular cholesterol transporter 1 and European Medicines Agency-approved lipid-lowering agent, as a potent autophagy activator. However, its efficacy against pulmonary fibrosis has not yet been evaluated. This study aimed to determine whether ezetimibe has therapeutic potential against idiopathic pulmonary fibrosis. Primary lung fibroblasts isolated from both humans and mice were employed for mechanistic in vitro experiments. mRNA sequencing of human lung fibroblasts and gene set enrichment analysis were performed to explore the therapeutic mechanism of ezetimibe. A bleomycin-induced pulmonary fibrosis mouse model was used to examine in vivo efficacy of the drug. Tandem fluorescent-tagged microtubule-associated protein 1 light chain 3 transgenic mice were used to measure autophagic flux. Finally, the medical records of patients with idiopathic pulmonary fibrosis from three different hospitals were retrospectively reviewed, and analyses on survival and lung function were conducted to determine the benefits of ezetimibe. Ezetimibe inhibited myofibroblast differentiation by restoring the mechanistic target of rapamycin complex 1-autophagy axis with fine control of intracellular cholesterol distribution. Serum response factor, a potential autophagic substrate, was identified as a primary downstream effector in this process. Similarly, ezetimibe ameliorated bleomycin-induced pulmonary fibrosis in mice by inhibiting mechanistic target of rapamycin complex 1 activity and increasing autophagic flux, as observed in mouse lung samples. Patients with idiopathic pulmonary fibrosis who regularly used ezetimibe showed decreased rates of all-cause mortality and lung function decline. In conclusion, our study presents ezetimibe as a potential novel therapeutic for idiopathic pulmonary fibrosis.

PMID:38359963 | DOI:10.1183/13993003.00580-2023

Categories: Literature Watch

Thin-Section CT in the Categorization and Management of Pulmonary Fibrosis including Recently Defined Progressive Pulmonary Fibrosis

Thu, 2024-02-15 06:00

Radiol Cardiothorac Imaging. 2024 Feb;6(1):e230135. doi: 10.1148/ryct.230135.

ABSTRACT

While idiopathic pulmonary fibrosis (IPF) is the most common type of fibrotic lung disease, there are numerous other causes of pulmonary fibrosis that are often characterized by lung injury and inflammation. Although often gradually progressive and responsive to immune modulation, some cases may progress rapidly with reduced survival rates (similar to IPF) and with imaging features that overlap with IPF, including usual interstitial pneumonia (UIP)-pattern disease characterized by peripheral and basilar predominant reticulation, honeycombing, and traction bronchiectasis or bronchiolectasis. Recently, the term progressive pulmonary fibrosis has been used to describe non-IPF lung disease that over the course of a year demonstrates clinical, physiologic, and/or radiologic progression and may be treated with antifibrotic therapy. As such, appropriate categorization of the patient with fibrosis has implications for therapy and prognosis and may be facilitated by considering the following categories: (a) radiologic UIP pattern and IPF diagnosis, (b) radiologic UIP pattern and non-IPF diagnosis, and (c) radiologic non-UIP pattern and non-IPF diagnosis. By noting increasing fibrosis, the radiologist contributes to the selection of patients in which therapy with antifibrotics can improve survival. As the radiologist may be first to identify developing fibrosis and overall progression, this article reviews imaging features of pulmonary fibrosis and their significance in non-IPF-pattern fibrosis, progressive pulmonary fibrosis, and implications for therapy. Keywords: Idiopathic Pulmonary Fibrosis, Progressive Pulmonary Fibrosis, Thin-Section CT, Usual Interstitial Pneumonia © RSNA, 2024.

PMID:38358328 | DOI:10.1148/ryct.230135

Categories: Literature Watch

Erratum: Idiopathic Pulmonary Fibrosis Is Associated with Common Genetic Variants and Limited Rare Variants

Thu, 2024-02-15 06:00

Am J Respir Crit Care Med. 2024 Feb 15;209(4):462. doi: 10.1164/rccm.v209erratum2.

NO ABSTRACT

PMID:38358128 | DOI:10.1164/rccm.v209erratum2

Categories: Literature Watch

A scoping review of the unmet needs of patients diagnosed with idiopathic pulmonary fibrosis (IPF)

Wed, 2024-02-14 06:00

PLoS One. 2024 Feb 14;19(2):e0297832. doi: 10.1371/journal.pone.0297832. eCollection 2024.

ABSTRACT

AIMS: Patients diagnosed with idiopathic pulmonary fibrosis (IPF) have a high symptom burden and numerous needs that remain largely unaddressed despite advances in available treatment options. There is a need to comprehensively identify patients' needs and create opportunities to address them. This scoping review aimed to synthesise the available evidence and identify gaps in the literature regarding the unmet needs of patients diagnosed with IPF.

METHODS: The protocol for the review was registered with Open Science Framework (DOI 10.17605/OSF.IO/SY4KM). A systematic search was performed in March 2022, in CINAHL, MEDLINE, Embase, PsychInfo, Web of Science Core Collection and ASSIA Applied Social Science Index. A comprehensive review of grey literature was also completed. Inclusion criteria included patients diagnosed with IPF and date range 2011-2022. A range of review types were included. Data was extracted using a data extraction form. Data was analysed using descriptive and thematic analysis. A total of 884 citations were reviewed. Ethical approval was not required.

RESULTS: 52 citations were selected for final inclusion. Five themes were identified: 1.) psychological impact of an IPF diagnosis. 2.) adequate information and education: at the right time and in the right way. 3.) high symptom burden support needs. 4.) referral to palliative care and advance care planning (ACP). 5.) health service provision-a systems approach.

CONCLUSION: This review highlights the myriad of needs patients with IPF have and highlights the urgent need for a systems approach to care, underpinned by an appropriately resourced multi-disciplinary team. The range of needs experienced by patients with IPF are broad and varied and require a holistic approach to care including targeted research, coupled with the continuing development of patient-focused services and establishment of clinical care programmes.

PMID:38354191 | DOI:10.1371/journal.pone.0297832

Categories: Literature Watch

Zinpentraxin Alfa for Idiopathic Pulmonary Fibrosis: The Randomized Phase III STARSCAPE Trial

Wed, 2024-02-14 06:00

Am J Respir Crit Care Med. 2024 Feb 14. doi: 10.1164/rccm.202401-0116OC. Online ahead of print.

ABSTRACT

RATIONALE: A phase II trial reported clinical benefit over 28 weeks in patients with idiopathic pulmonary fibrosis who received zinpentraxin alfa.

OBJECTIVES: To investigate the efficacy and safety of zinpentraxin alfa in patients with idiopathic pulmonary fibrosis in a phase III trial.

METHODS: This 52-week phase III, double-blind, placebo-controlled, pivotal trial was conducted at 275 sites in 29 countries. Patients with idiopathic pulmonary fibrosis were randomized 1:1 to intravenous placebo or zinpentraxin alfa 10 mg/kg every four weeks. The primary endpoint was absolute change from baseline to Week 52 in forced vital capacity. Secondary endpoints included absolute change from baseline to Week 52 in percent predicted forced vital capacity and six-minute walking distance. Safety was monitored via adverse events. Post-hoc analysis of the phase II and phase III data explored changes in forced vital capacity and their impact on the efficacy results.

MEASUREMENTS AND MAIN RESULTS: Of 664 randomized patients, 333 were assigned to placebo and 331 to zinpentraxin alfa. Four of the 664 randomized patients were never administered study drug. The trial was terminated early following a pre-specified futility analysis that demonstrated no treatment benefit of zinpentraxin alfa over placebo. In the final analysis, absolute change from baseline to Week 52 in forced vital capacity was similar between placebo and zinpentraxin alfa (‒214.89 mL and ‒235.72 mL; P = 0.5420); there were no apparent treatment effects on secondary endpoints. Overall, 72.3% and 74.6% of patients receiving placebo and zinpentraxin alfa, respectively, experienced ≥1 adverse event. Post-hoc analysis revealed that extreme forced vital capacity decline in two placebo-treated patients resulted in the clinical benefit of zinpentraxin alfa reported by phase II.

CONCLUSIONS: Zinpentraxin alfa treatment did not benefit patients with idiopathic pulmonary fibrosis over placebo. Learnings from this program may help improve decision-making around trials in idiopathic pulmonary fibrosis. Clinical trial registration available at www.

CLINICALTRIALS: gov, ID: NCT04552899.

PMID:38354066 | DOI:10.1164/rccm.202401-0116OC

Categories: Literature Watch

Fibrotic lung diseases in children

Wed, 2024-02-14 06:00

Pediatr Pulmonol. 2024 Feb 14. doi: 10.1002/ppul.26905. Online ahead of print.

ABSTRACT

In children, pulmonary fibrosis (PF) is an extremely unusual entity that can be observed in some types of interstitial lung disease (ILD). Defining whether ILD is accompanied by PF is important for targeted therapy. Algorithm for the diagnosis of PF in children is not clearly established. Besides, the clinical, radiological, and histological definitions commonly used to diagnose particularly the cases of idiopathic PF in adult patients, is not applicable to pediatric cases. However, a few studies conducted in children offer good exemplary diagnostic approach to fibrosing ILD. Thorax high resonance computed tomography and/or lung biopsy scanning can provide valuable information about PF. Another issue that has not been clearly established is when to start antifibrotic treatment in pediatric patients with PF. The objective of this current review is to provide a comprehensive overview of pediatric PF by drawing upon adult research, particularly focusing on the areas of uncertainty.

PMID:38353393 | DOI:10.1002/ppul.26905

Categories: Literature Watch

Stimuli-specific senescence of primary human lung fibroblasts modulates alveolar stem cell function

Wed, 2024-02-14 06:00

Res Sq. 2024 Jan 29:rs.3.rs-3879423. doi: 10.21203/rs.3.rs-3879423/v1. Preprint.

ABSTRACT

Aging is the main risk factor for chronic lung diseases (CLDs) including idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD). Accordingly, hallmarks of aging such as cellular senescence are present in different lung cell types such as fibroblasts in these patients. However, whether the senescent phenotype of fibroblasts derived from IPF or COPD patients differs is still unknown. Therefore, we characterized senescence at baseline and after exposure to disease-relevant insults (H 2 O 2 , bleomycin, and TGF-β1) in cultured primary human lung fibroblasts (phLF) from control donors, IPF, or COPD patients. We found that phLF from different disease-origins have a low baseline senescence. H 2 O 2 and bleomycin treatment induced a senescent phenotype in phLF, whereas TGF-β1 had primarily a pro-fibrotic effect. Notably, we did not observe any differences in susceptibility to senescence induction in phLF based on disease origin, while exposure to different stimuli resulted in distinct senescence programs in phLF. Moreover, senescent phLF reduced colony formation efficiency of distal alveolar epithelial progenitor cells in a stimuli-dependent manner. In conclusion, the senescent phenotype of phLF is mainly determined by the senescence inducer and impairs alveolar epithelial progenitor capacity in vitro .

PMID:38352619 | PMC:PMC10862971 | DOI:10.21203/rs.3.rs-3879423/v1

Categories: Literature Watch

Three dimensional fibrotic extracellular matrix directs microenvironment fiber remodeling by fibroblasts

Tue, 2024-02-13 06:00

Acta Biomater. 2024 Feb 11:S1742-7061(24)00066-7. doi: 10.1016/j.actbio.2024.02.008. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF), for which effective treatments are limited, results in excessive and disorganized deposition of aberrant extracellular matrix (ECM). An altered ECM microenvironment is postulated to contribute to disease progression through inducing profibrotic behavior of lung fibroblasts, the main producers and regulators of ECM. Here, we examined this hypothesis in a 3D in vitro model system by growing primary human lung fibroblasts in ECM-derived hydrogels from non-fibrotic (control) or IPF lung tissue. Using this model, we compared how control and IPF lung-derived fibroblasts responded in control and fibrotic microenvironments in a combinatorial manner. Culture of fibroblasts in fibrotic hydrogels did not alter in the overall amount of collagen or glycosaminoglycans but did cause a drastic change in fiber organization compared to culture in control hydrogels. High-density collagen percentage was increased by control fibroblasts in IPF hydrogels at day 7, but decreased at day 14. In contrast, IPF fibroblasts only decreased the high-density collagen percentage at day 14, which was accompanied by enhanced fiber alignment in IPF hydrogels. Similarly, stiffness of fibrotic hydrogels was increased only by control fibroblasts by day 14 while those of control hydrogels were not altered by fibroblasts. These data highlight how the ECM-remodeling responses of fibroblasts are influenced by the origin of both the cells and the ECM. Moreover, by showing how the 3D microenvironment plays a crucial role in directing cells, our study paves the way in guiding future investigations examining fibrotic processes with respect to ECM remodeling responses of fibroblasts. STATEMENT OF SIGNIFICANCE: In this study, we investigated the influence of the altered extracellular matrix (ECM) in Idiopathic Pulmonary Fibrosis (IPF), using a 3D in vitro model system composed of ECM-derived hydrogels from both IPF and control lungs, seeded with human IPF and control lung fibroblasts. While our results indicated that fibrotic microenvironment did not change the overall collagen or glycosaminoglycan content, it resulted in a dramatically alteration of fiber organization and mechanical properties. Control fibroblasts responded differently from IPF fibroblasts, highlighting the unique instructive role of the fibrotic ECM and the interplay with fibroblast origin. These results underscore the importance of 3D microenvironments in guiding pro-fibrotic responses, offering potential insights for future IPF therapies as well as other fibrotic diseases and cancer.

PMID:38350556 | DOI:10.1016/j.actbio.2024.02.008

Categories: Literature Watch

Transcriptomic and network analysis identifies shared and unique pathways and immune changes across fibrotic interstitial lung diseases

Tue, 2024-02-13 06:00

Aging (Albany NY). 2024 Feb 12;16. doi: 10.18632/aging.205530. Online ahead of print.

ABSTRACT

BACKGROUND: Interstitial lung disease (ILD) encompasses a diverse group of disorders characterized by chronic inflammation and fibrosis of the pulmonary interstitium. Three ILDs, namely idiopathic pulmonary fibrosis (IPF), fibrotic hypersensitivity pneumonitis (fHP), and connective tissue disease-associated ILD (CTD-ILD), exhibit similar progressive fibrosis phenotypes, yet possess distinct etiologies, encouraging us to explore their different underlying mechanisms.

METHODS: Transcriptome data of fibrotic lung tissues from patients with IPF, fHP, and CTD-ILD were subjected to functional annotation, network, and pathway analyses. Additionally, we employed the xCell deconvolution algorithm to predict immune cell infiltration in patients with fibrotic ILDs and healthy controls.

RESULTS: We identified a shared progressive fibrosis-related module in these diseases which was related to extracellular matrix (ECM) degradation and production and potentially regulated by the p53 family transcription factors. In IPF, neuron-related processes emerged as a critical specific mechanism in functional enrichment. In fHP, we observed that B cell signaling and immunoglobulin A (IgA) production may act as predominant processes, which was further verified by B cell infiltration and the central role of CD19 gene. In CTD-ILD, active chemokine processes were enriched, and active dendritic cells (aDCs) were predicted to infiltrate the lung tissues.

CONCLUSIONS: This study revealed shared and specific molecular and cellular pathways among IPF, fHP, and CTD-ILD, providing a basis for understanding their pathogenesis and identifying potential therapeutic targets.

PMID:38349858 | DOI:10.18632/aging.205530

Categories: Literature Watch

Standigm ASK™: knowledge graph and artificial intelligence platform applied to target discovery in idiopathic pulmonary fibrosis

Tue, 2024-02-13 06:00

Brief Bioinform. 2024 Jan 22;25(2):bbae035. doi: 10.1093/bib/bbae035.

ABSTRACT

Standigm ASK™ revolutionizes healthcare by addressing the critical challenge of identifying pivotal target genes in disease mechanisms-a fundamental aspect of drug development success. Standigm ASK™ integrates a unique combination of a heterogeneous knowledge graph (KG) database and an attention-based neural network model, providing interpretable subgraph evidence. Empowering users through an interactive interface, Standigm ASK™ facilitates the exploration of predicted results. Applying Standigm ASK™ to idiopathic pulmonary fibrosis (IPF), a complex lung disease, we focused on genes (AMFR, MDFIC and NR5A2) identified through KG evidence. In vitro experiments demonstrated their relevance, as TGFβ treatment induced gene expression changes associated with epithelial-mesenchymal transition characteristics. Gene knockdown reversed these changes, identifying AMFR, MDFIC and NR5A2 as potential therapeutic targets for IPF. In summary, Standigm ASK™ emerges as an innovative KG and artificial intelligence platform driving insights in drug target discovery, exemplified by the identification and validation of therapeutic targets for IPF.

PMID:38349059 | PMC:PMC10862655 | DOI:10.1093/bib/bbae035

Categories: Literature Watch

Single‑agent nintedanib suppresses metastatic osteosarcoma growth by inhibiting tumor vascular formation

Tue, 2024-02-13 06:00

Oncol Lett. 2024 Jan 25;27(3):123. doi: 10.3892/ol.2024.14254. eCollection 2024 Mar.

ABSTRACT

New therapeutic approaches are needed for osteosarcoma, which is the most common malignancy of the bone, especially for metastatic cases. Nintedanib is a potent, oral tyrosine kinase inhibitor approved for treating idiopathic pulmonary fibrosis, which blocks a variety of receptor signals, including fibroblast growth factor receptors, vascular endothelial growth factor receptors and platelet-derived growth factor receptors. The present study assessed the effect of nintedanib on previously developed mouse AXT osteosarcoma cells, and on AXT-derived osteosarcoma developed in C57BL/6 mice, which displays lethal tumors with osteoid formation and lung metastatic lesions that mimics human disease. In vitro analysis, including flow cytometry and immunoblotting, revealed that nintedanib inhibited AXT cell proliferation and cell cycle progression, induced apoptosis, and inactivated AKT and ERK1/2. Immunoblot analysis using tumor lysates demonstrated that nintedanib inhibited its target molecules in vivo. As a single agent, nintedanib decreased the size of primary AXT-derived osteosarcoma, and reduced circulating tumor cells and lung metastasis. Immunohistochemical findings indicated that nintedanib exerted antitumor activity mainly by inhibiting the formation of CD31-positive tumor vasculature, while αSMA-positive cells were still enriched in tumors after nintedanib treatment. In addition, nintedanib exhibited an anti-osteosarcoma effect on C57BL/6 severe combined immunodeficient mice in which T- and B-cell function is obsolete, suggesting that the antitumor effect of nintedanib was not attributable to antitumor immunity. Collectively, these findings indicated that nintedanib holds potential for treating osteosarcoma.

PMID:38348384 | PMC:PMC10859826 | DOI:10.3892/ol.2024.14254

Categories: Literature Watch

Overnight desaturation in interstitial lung diseases: links to pulmonary vasculopathy and mortality

Tue, 2024-02-13 06:00

ERJ Open Res. 2024 Feb 12;10(1):00740-2023. doi: 10.1183/23120541.00740-2023. eCollection 2024 Jan.

ABSTRACT

BACKGROUND: Overnight desaturation predicts poor prognosis across interstitial lung diseases (ILDs). The aim of the present study was to investigate whether nocturnal desaturation is associated with pulmonary vasculopathy and mortality.

METHODS: A retrospective single centre study of 397 new ILD patients was carried out including patients with idiopathic pulmonary fibrosis (IPF) (n=107) and patients with non-IPF fibrotic ILD (n=290). This is the largest study to date of the effect of significant nocturnal desaturation (SND) (≥10% of total sleep time with oxygen saturation ≤90% measured by pulse oximetry).

RESULTS: The prevalence of SND was 28/107 (26.2%) in IPF and 80/290 (27.6%) in non-IPF ILD. The prevalence of SND was higher in non-IPF ILDs than in IPF (p=0.025) in multivariate analysis. SND was associated with noninvasive markers of pulmonary hypertension (PH): tricuspid regurgitation velocity (TRV) (p<0.0001), brain natriuretic peptide (p<0.007), carbon monoxide transfer coefficient (p<0.0001), A-a gradient (p<0.0001), desaturation >4% in 6-min walking test (p<0.03) and pulmonary artery diameter (p<0.005). SND was independently associated with high echocardiographic PH probability in the entire cohort (OR 2.865, 95% CI 1.486-5.522, p<0.002) and in non-IPF fibrotic ILD (OR 3.492, 95% CI 1.597-7.636, p<0.002) in multivariate analysis. In multivariate analysis, SND was associated with mortality in the entire cohort (OR 1.734, 95% CI 1.202-2.499, p=0.003) and in IPF (OR 1.908, 95% CI 1.120-3.251, p=0.017) and non-IPF fibrotic ILD (OR 1.663, 95% CI 1.000-2.819, p=0.041). Separate models with exclusion of each one of the diagnostic subgroups showed that no subgroup was responsible for this finding in non-IPF ILDs. SND was a stronger marker of 5-year mortality than markers of PH.

CONCLUSION: SND was associated with high echocardiographic probability and mortality and was a stronger predictor of mortality in IPF and non-IPF ILDs grouped together to power the study.

PMID:38348245 | PMC:PMC10860199 | DOI:10.1183/23120541.00740-2023

Categories: Literature Watch

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