Respir Res. 2024 Apr 24;25(1):176. doi: 10.1186/s12931-024-02816-z.

ABSTRACT

BACKGROUND: Abnormal lipid metabolism has recently been reported as a crucial signature of idiopathic pulmonary fibrosis (IPF). However, the origin and biological function of the lipid and possible mechanisms of increased lipid content in the pathogenesis of IPF remains undetermined.

METHODS: Oil-red staining and immunofluorescence analysis were used to detect lipid accumulation in mouse lung fibrosis frozen sections, Bleomycin-treated human type II alveolar epithelial cells (AECIIs) and lung fibroblast. Untargeted Lipid omics analysis was applied to investigate differential lipid species and identified LysoPC was utilized to treat human lung fibroblasts and mice. Microarray and single-cell RNA expression data sets identified lipid metabolism-related differentially expressed genes. Gain of function experiment was used to study the function of 3-hydroxy-3-methylglutaryl-Coa Synthase 2 (HMGCS2) in regulating AECIIs lipid metabolism. Mice with AECII-HMGCS2 high were established by intratracheally delivering HBAAV2/6-SFTPC- HMGCS2 adeno-associated virus. Western blot, Co-immunoprecipitation, immunofluorescence, site-directed mutation and flow cytometry were utilized to investigate the mechanisms of HMGCS2-mediated lipid metabolism in AECIIs.

RESULTS: Injured AECIIs were the primary source of accumulated lipids in response to Bleomycin stimulation. LysoPCs released by injured AECIIs could activate lung fibroblasts, thus promoting the progression of pulmonary fibrosis. Mechanistically, HMGCS2 was decreased explicitly in AECIIs and ectopic expression of HMGCS2 in AECIIs using the AAV system significantly alleviated experimental mouse lung fibrosis progression via modulating lipid degradation in AECIIs through promoting CPT1A and CPT2 expression by interacting with PPARα.

CONCLUSIONS: These data unveiled a novel etiological mechanism of HMGCS2-mediated AECII lipid metabolism in the genesis and development of pulmonary fibrosis and provided a novel target for clinical intervention.

PMID:38658970 | DOI:10.1186/s12931-024-02816-z

Sheng Li Xue Bao. 2024 Apr 25;76(2):346-352.

ABSTRACT

Programmed death-ligand 1 (PD-L1) is important in maintaining central and peripheral immune tolerance in normal tissues, mediating tumor immune escape and keeping the balance between anti- and pro-inflammatory responses. Inflammation plays an important role in inflammatory lung diseases. This article reviews the research progress and potential clinical value of PD-L1 in inflammatory lung diseases, including acute lung injury, chronic obstructive pulmonary disease, asthma and idiopathic pulmonary fibrosis.

PMID:38658383

Biomed J. 2024 Apr 22:100729. doi: 10.1016/j.bj.2024.100729. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) diagnosis is still the diagnosis of exclusion. Differentiating from other forms of interstitial lung diseases (ILDs) is essential, given the various therapeutic approaches. The IPF course is now unpredictable for individual patients, although some genetic factors and several biomarkers have already been associated with various IPF prognoses. Since its early stages, IPF may be asymptomatic, leading to a delayed diagnosis. The present review critically examines the recent literature on molecular biomarkers potentially useful in IPF diagnostics. The examined biomarkers are grouped into breath and sputum biomarkers, serologically assessed extracellular matrix neoepitope markers, and oxidative stress biomarkers in lung tissue. Fibroblasts and complete blood count have also gained recent interest in that respect. Although several biomarker candidates have been profiled, there has yet to be a single biomarker that proved specific to the IPF disease. Nevertheless, various IPF biomarkers have been used in preclinical and clinical trials to verify their predictive and monitoring potential.

PMID:38657859 | DOI:10.1016/j.bj.2024.100729

Am J Respir Cell Mol Biol. 2024 Apr 24. doi: 10.1165/rcmb.2023-0290OC. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is an aging-associated interstitial lung disease resulting from repeated epithelial injury and inadequate epithelial repair. Alveolar type II cells (AEC2) are progenitor cells that maintain epithelial homeostasis and repair the lung after injury. In the current study, we assessed lipid metabolism in AEC2s from human lungs of IPF patients and healthy donors, as well as AEC2s from bleomycin-injured young and old mice. Through single cell RNA sequencing (scRNA-seq), we observed that lipid metabolism-related genes were downregulated in IPF AEC2s and bleomycin-injured mouse AEC2s. Aging aggravated this decrease and hindered recovery of lipid metabolism gene expression in AEC2s after bleomycin injury. Pathway analyses revealed down-regulation of genes related to lipid biosynthesis and fatty acid -oxidation in AEC2s from IPF lungs and bleomycin-injured, aged mouse lungs compared to the respective controls. We confirmed decreased cellular lipid content in AEC2s from IPF lungs and bleomycin-injured, aged mouse lungs using immunofluorescence staining and flow cytometry. We further show that lipid metabolism was associated with AEC2 progenitor function. Lipid supplementation and peroxisome proliferator activated receptor gamma (PPARγ) activation promoted progenitor renewal capacity of both human and mouse AEC2s in 3D organoid cultures. Lipid supplementation also increased AEC2 proliferation and expression of SFTPC in AEC2s. In summary, we identified a lipid metabolism deficiency in AEC2s from lungs of patients with IPF and bleomycin-injured aged mice. Restoration of lipid metabolism homeostasis in AEC2s might promote AEC2 progenitor function and offer new opportunities for therapeutic approaches to IPF.

PMID:38657143 | DOI:10.1165/rcmb.2023-0290OC

Ther Umsch. 2024 Feb;81(1):12-15.

ABSTRACT

Progressive pulmonary Fibrosis Abstract: Cough and dyspnea on excertion are common and early symptoms of interstitial lung diseases (ILD). Thoracic imaging (particularly computed tomography) detects such lung structural alterations early in the disease course. Knowledge of these diseases and their management is necessary in the daily business. The term "progressive pulmonary fibrosis" subsumes a heterogene group of interstitial lung diseases with a similar course of progressive fibrosis. The management of these diseases should be discussed interdisciplinary, similar to the management of the Idiopathic pulmonary fibrosis (IPF). Antifibrotic drugs are new therapeutic options.

PMID:38655828

Heliyon. 2024 Apr 15;10(8):e29266. doi: 10.1016/j.heliyon.2024.e29266. eCollection 2024 Apr 30.

ABSTRACT

BACKGROUND: At the beginning of 21st century, reclassification of fibrosing interstitial lung diseases (ILD) scored academic concerning, and then propelled development. Decade before, pifenidone and nintedanib were approved for idiopathic pulmonary fibrosis, but no more drugs are yet available. To evaluate the development traits of pirfenidone and nintedanib in fibrosing ILD, including the influential country, institution, authors, keywords, and the major problems or the priorities of the field emerge and evolve, bibliometric analysis was used to summarize and draw scientific knowledge maps.

METHODS: We confined the words to "pirfenidone", "nintedanib", "pulmonary fibrosis", and "lung disease, interstitial". Publications were retrieved from the Web of Science Core Collection on February 24, 2024 with the search strategies. Citespace and VOSviewer were adopted for bibliometric analysis.

RESULTS: For the knowledge map of pirfenidone, a total of 4359 authors from 279 institutions in 58 countries/regions contributed to 538 studies. The United States and Italy are way ahead. Genentech Inc and the University of Turin are the institutions with the strongest influence. AM J RESP CRIT CARE is the maximized influential periodical. Raghu G was the most frequently co-cited scholar. keywords cluster demonstrated that vital capacity, safety, outcome, effectiveness, acute exacerbation, pathway, cell, collagen were the hotspots. The burst timeline of hotspots and references revealed academic transitions of pirfenidone-related studies. About the knowledge map of nintedanib, 3297 authors from 238 institutions in 47 countries/regions published 374 studies. Japan, the United States, and Italy are the most productive countries. Boehringer Ingelheim is the overriding productive institution. New ENGL J MED have important roles in reporting milestones of nintedanib. Richeldi L carried numerous capital publications to support the anti-fibrotic effect of nintedanib. From the network of co-occurrence keywords, idiopathic pulmonary fibrosis, efficacy, and safety were the hotspots. Nintedanib for systemic sclerosis-related ILD and progressive pulmonary fibrosis is the hotspot with sharp evolution recently.

CONCLUSIONS: We summarized and showed developmental alterations of pirfenidone and nintedanib in fibrosing ILD through bibliographic index-based analysis. Our findings showed just dozen years sharp development period of pirfenidone and nintedanib in ILD, and identifies potential partners for interested researchers. The burst of hotspots demonstrated the evolvement of research priorities and major problems, and we observed the transition of keywords from experimental terms like mouse, bleomycin, cell, pathway, collagen, gene expression, to clinical terms including efficacy, safety, survival, acute exacerbation, and progressive pulmonary fibrosis. In the future, exploration about disparity models of drug administration, differences between early and later initiate anti-fibrotic therapy, both short-term and long-term efficacy of pirfenidone and nintedanib in fibrosing ILD, specifically in connective disease associate ILD would be emphatically concerned by pulmonologists.

PMID:38655311 | PMC:PMC11036012 | DOI:10.1016/j.heliyon.2024.e29266

bioRxiv [Preprint]. 2024 Jan 16:2023.12.01.569608. doi: 10.1101/2023.12.01.569608.

ABSTRACT

RATIONALE: The role of the innate immune system in Idiopathic Pulmonary Fibrosis (IPF) remains poorly understood. However, a functional myeloid compartment is required to remove dying cells and cellular debris, and to mediate innate immune responses against pathogens. Aberrant macrophage activity has been described in patients with Post-acute sequelae of COVID fibrosis (PASC-F). Therefore, we examined the functional and synthetic properties of myeloid cells isolated from normal donor lung and lung explant tissue from both IPF and PASC-F patients and explored the effect of LTI-2355, a Caveolin Scaffolding Domain (CSD) peptide, on these cells.

METHODS & RESULTS: CD45 + myeloid cells isolated from lung explant tissue from IPF and PASC-F patients exhibited an impaired capacity to clear autologous dead cells and cellular debris. Uptake of pathogen-coated bioparticles was impaired in myeloid cells from both fibrotic patient groups independent of type of pathogen highlighting a cell intrinsic functional impairment. LTI-2355 improved the phagocytic activity of both IPF and PASC-F myeloid cells, and this improvement was paired with decreased pro-inflammatory and pro-fibrotic synthetic activity. LTI-2355 was also shown to primarily target CD206-expressing IPF and PASC-F myeloid cells.

CONCLUSIONS: Primary myeloid cells from IPF and PASC-F patients exhibit dysfunctional phagocytic and synthetic properties that are reversed by LTI-2355. Thus, these studies highlight an additional mechanism of action of a CSD peptide in the treatment of IPF and progressive fibrotic lung disease.

PMID:38654821 | PMC:PMC11037873 | DOI:10.1101/2023.12.01.569608

Sci Prog. 2024 Apr-Jun;107(2):368504241247402. doi: 10.1177/00368504241247402.

ABSTRACT

Idiopathic pulmonary fibrosis is a chronic and progressive interstitial lung disease with a poor prognosis. Idiopathic pulmonary fibrosis is characterized by repeated alveolar epithelial damage leading to abnormal repair. The intercellular microenvironment is disturbed, leading to continuous activation of fibroblasts and myofibroblasts, deposition of extracellular matrix, and ultimately fibrosis. Moreover, pulmonary fibrosis was also found as a COVID-19 complication. Currently, two drugs, pirfenidone and nintedanib, are approved for clinical therapy worldwide. However, they can merely slow the disease's progression rather than rescue it. These two drugs have other limitations, such as lack of efficacy, adverse effects, and poor pharmacokinetics. Consequently, a growing number of molecular therapies have been actively developed. Treatment options for IPF are becoming increasingly available. This article reviews the research platform, including cell and animal models involved in molecular therapy studies of idiopathic pulmonary fibrosis as well as the promising therapeutic targets and their development progress during clinical trials. The former includes patient case/control studies, cell models, and animal models. The latter includes transforming growth factor-beta, vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factor, lysophosphatidic acid, interleukin-13, Rho-associated coiled-coil forming protein kinase family, and Janus kinases/signal transducers and activators of transcription pathway. We mainly focused on the therapeutic targets that have not only entered clinical trials but were publicly published with their clinical outcomes. Moreover, this work provides an outlook on some promising targets for further validation of their possibilities to cure the disease.

PMID:38651330 | DOI:10.1177/00368504241247402

Clin Pharmacol Drug Dev. 2024 Apr 23. doi: 10.1002/cpdd.1403. Online ahead of print.

ABSTRACT

Zinpentraxin alfa is a recombinant form of the human pentraxin-2 that was studied in idiopathic pulmonary fibrosis (IPF). To improve the purity and yield of the drug material, a 2nd-generation drug product was developed. To characterize and compare the pharmacokinetic (PK) properties of the 1st- and 2nd-generation zinpentraxin alfa, PK studies were conducted in healthy volunteers (HVs). In a phase 1 randomized, double-blind, 2-sequence crossover, sequential 2-stage study (ISRCTN59409907), single intravenous (IV) doses of 1st- and 2nd-generation zinpentraxin alfa at 10 mg/kg were studied with a blinded interim analysis (IA) at the end of stage 1. Bioequivalence (BE) was achieved for the maximum observed plasma concentration (Cmax), but the overall exposure was higher for the 2nd- compared to the 1st-generation zinpentraxin alfa. The study was stopped after stage 1 as the gating criteria were met based on the result of the blinded IA. Safety profiles were similar for the 1st- and 2nd-generation drug products, and antidrug antibody (ADA) was not observed in this study.

PMID:38651245 | DOI:10.1002/cpdd.1403

Cureus. 2024 Mar 20;16(3):e56599. doi: 10.7759/cureus.56599. eCollection 2024 Mar.

ABSTRACT

Tension pneumomediastinum with hemodynamic failure is a rare but life-threatening condition. Rapid decompression of the mediastinum by drainage is essential to save the patient's life. This report presents a case of tension pneumomediastinum that developed during conservative management of a pneumomediastinum associated with idiopathic pulmonary fibrosis. Endoscopically guided mediastinal drainage was successfully performed in the emergency situation of tension pneumomediastinum. Using the semi-flexible fiberscope inserted through a subxiphoid approach, the drainage catheter was easily and safely placed at the appropriate site in the mediastinum. Good mediastinal decompression was achieved, and the patient was out of this critical condition.

PMID:38650778 | PMC:PMC11034704 | DOI:10.7759/cureus.56599

Thorax. 2024 Apr 22:thorax-2023-220856. doi: 10.1136/thorax-2023-220856. Online ahead of print.

ABSTRACT

BACKGROUND: A usual interstitial pneumonia (UIP) pattern of lung injury is a key feature of idiopathic pulmonary fibrosis (IPF) and is also observed in up to 40% of individuals with rheumatoid arthritis (RA)-associated interstitial lung disease (RA-ILD). The RA-UIP phenotype could result from either a causal relationship of RA on UIP or vice versa, or from a simple co-occurrence of RA and IPF due to shared demographic, genetic or environmental risk factors.

METHODS: We used two-sample bidirectional Mendelian randomisation (MR) to test the hypothesis of a causal effect of RA on UIP and of UIP on RA, using variants from genome-wide association studies (GWAS) of RA (separately for seropositive (18 019 cases and 991 604 controls) and seronegative (8515 cases and 1 015 471 controls) RA) and of IPF (4125 cases and 20 464 controls) as genetic instruments. Sensitivity analyses were conducted to assess the robustness of the results to violations of the MR assumptions.

FINDINGS: IPF showed a significant causal effect on seropositive RA, with developing IPF increasing the risk of seropositive RA (OR=1.06, 95% CI: 1.04 to 1.08, p<0.001) which was robust under all models. For the MR in the other direction, seropositive RA showed a significant protective effect on IPF (OR=0.93; 95% CI: 0.87 to 0.99; p=0.032), but the effect was not significant when sensitivity analyses were applied. This was likely because of bias due to exclusion of patients with RA from among the cases in the IPF GWAS, or possibly because our genetic instruments did not fully capture the effect of the complex human leucocyte antigen region, the strongest RA genetic risk factor.

INTERPRETATION: Our findings support the hypothesis that RA-UIP may be due to a cause-effect relationship between UIP and RA, rather than due to a coincidental occurrence of IPF in patients with RA. The significant causal effect of IPF on seropositive RA suggests that pathomechanisms involved in the development of UIP may promote RA, and this may help inform future guidelines on screening for ILD in patients with RA.

PMID:38649271 | DOI:10.1136/thorax-2023-220856

JAMA. 2024 Apr 22. doi: 10.1001/jama.2024.3669. Online ahead of print.

ABSTRACT

IMPORTANCE: Interstitial lung disease (ILD) consists of a group of pulmonary disorders characterized by inflammation and/or fibrosis of the lung parenchyma associated with progressive dyspnea that frequently results in end-stage respiratory failure. In the US, ILD affects approximately 650 000 people and causes approximately 25 000 to 30 000 deaths per year.

OBSERVATIONS: The most common forms of ILD are idiopathic pulmonary fibrosis (IPF), which accounts for approximately one-third of all cases of ILD, hypersensitivity pneumonitis, accounting for 15% of ILD cases, and connective tissue disease (CTD), accounting for 25% of ILD cases. ILD typically presents with dyspnea on exertion. Approximately 30% of patients with ILD report cough. Thoracic computed tomography is approximately 91% sensitive and 71% specific for diagnosing subtypes of ILDs such as IPF. Physiologic assessment provides important prognostic information. A 5% decline in forced vital capacity (FVC) over 12 months is associated with an approximately 2-fold increase in mortality compared with no change in FVC. Antifibrotic therapy with nintedanib or pirfenidone slows annual FVC decline by approximately 44% to 57% in individuals with IPF, scleroderma associated ILD, and in those with progressive pulmonary fibrosis of any cause. For connective tissue disease-associated ILD, immunomodulatory therapy, such as tocilizumab, rituximab, and mycophenolate mofetil, may slow decline or even improve FVC at 12-month follow-up. Structured exercise therapy reduces symptoms and improves 6-minute walk test distance in individuals with dyspnea. Oxygen reduces symptoms and improves quality of life in individuals with ILD who desaturate below 88% on a 6-minute walk test. Lung transplant may improve symptoms and resolve respiratory failure in patients with end-stage ILD. After lung transplant, patients with ILD have a median survival of 5.2 to 6.7 years compared with a median survival of less than 2 years in patients with advanced ILD who do not undergo lung transplant. Up to 85% of individuals with end-stage fibrotic ILD develop pulmonary hypertension. In these patients, treatment with inhaled treprostinil improves walking distance and respiratory symptoms.

CONCLUSIONS AND RELEVANCE: Interstitial lung disease typically presents with dyspnea on exertion and can progress to respiratory failure. First-line therapy includes nintedanib or pirfenidone for IPF and mycophenolate mofetil for ILD due to connective tissue disease. Lung transplant should be considered for patients with advanced ILD. In patients with ILD, exercise training improves 6-minute walk test distance and quality of life.

PMID:38648021 | DOI:10.1001/jama.2024.3669

Am J Physiol Cell Physiol. 2024 Apr 22. doi: 10.1152/ajpcell.00681.2023. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is marked by the activation of fibroblasts, leading to excessive production and deposition of extracellular matrix (ECM) within the lung parenchyma. Despite the pivotal role of ECM overexpression in IPF, potential negative regulators of ECM production in fibroblasts have yet to be identified. Semaphorin class 3B (SEMA3B), a secreted protein highly expressed in lung tissues, has established roles in axonal guidance and tumor suppression. However, the role of SEMA3B in ECM production by fibroblasts in the pathogenesis of IPF remains unexplored. Here, we show the downregulation of SEMA3B and its cognate binding receptor, neuropilin 1 (NRP1) in IPF lungs compared with healthy controls. Notably, the reduced expression of SEMA3B and NRP1 is associated with a decline in lung function in IPF. The downregulation of SEMA3B and NRP1 transcripts was validated in the lung tissues of patients with IPF, and two alternative mouse models of pulmonary fibrosis. In addition, we show that TGFβ functions as a negative regulator of SEMA3B and NRP1 expression in lung fibroblasts. Furthermore, we demonstrate the anti-fibrotic effects of SEMA3B against TGFβ-induced ECM production in IPF lung fibroblasts. Overall, our findings uncovered a novel role of SEMA3B in the pathogenesis of pulmonary fibrosis and provided novel insights into modulating the SEMA3B-NRP1 axis to attenuate pulmonary fibrosis.

PMID:38646784 | DOI:10.1152/ajpcell.00681.2023

Toxicol Appl Pharmacol. 2024 Apr 19:116939. doi: 10.1016/j.taap.2024.116939. Online ahead of print.

ABSTRACT

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 suppresses 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.

PMID:38643951 | DOI:10.1016/j.taap.2024.116939

Eur J Radiol. 2024 Apr 18;175:111473. doi: 10.1016/j.ejrad.2024.111473. Online ahead of print.

ABSTRACT

PURPOSE: To investigate the clinical utility, reproducibility, and radiologists' acceptance of the Interstitial Lung Disease Imaging-Reporting and Data System (ILD-RADS).

METHOD: In this single-institutional retrospective study, three radiologists independently reviewed the chest high-resolution CT (HRCT) scans of 111 consecutive patients diagnosed with ILDs. They assessed the HRCT pulmonary features using the ILD-RADS template and assigned an ILD-RADS category (1-4) to each scan based on the identified imaging pattern. Patients were classified into idiopathic pulmonary fibrosis (IPF) (n = 14) and non-IPF ILD (n = 97) groups based on clinical diagnoses determined by multidisciplinary discussion. Association between ILD-RADS categories and clinical diagnoses was assessed using the Chi-square test for trend. Reproducibility was evaluated using kappa (k) scores, and radiologists' acceptance of the ILD-RADS was evaluated with a questionnaire.

RESULTS: We found a significant association between the ILD-RADS categories and patients' clinical diagnoses (P ≤ 0.0001) for the three readers, with a trend toward increased assignment of ILD-RADS-1 to IPF patients (50 %-57.1 %), and ILD-RADS-4 to non-IPF patients (46.4 %-49.5 %). The ILD-RADS categories showed excellent intra-reader agreement (k = 0.873) and moderate inter-reader agreement (k = 0.440). ILD-RADS-1 and -4 categories showed the highest inter-reader agreement (k = 0.681 and 0.481, respectively). Radiologists gave a positive response to using the ILD-RADS in daily practice.

CONCLUSIONS: The clinical utility of the ILD-RADS was demonstrated by the significant association between the ILD-RADS categories and patients' clinical diagnoses, particularly the ILD-RADS-1 and -4 categories. Excellent intra-reader and moderate inter-reader reproducibility was observed. ILD-RADS has the potential to be widely accepted for standardized HRCT reporting among radiologists.

PMID:38643528 | DOI:10.1016/j.ejrad.2024.111473

Hum Mol Genet. 2024 Apr 18;33(9):818-834. doi: 10.1093/hmg/ddae015.

ABSTRACT

Telomeres are nucleoprotein structures at the end of chromosomes that maintain their integrity. Mutations in genes coding for proteins involved in telomere protection and elongation produce diseases such as dyskeratosis congenita or idiopathic pulmonary fibrosis known as telomeropathies. These diseases are characterized by premature telomere shortening, increased DNA damage and oxidative stress. Genetic diagnosis of telomeropathy patients has identified mutations in the genes TERT and TERC coding for telomerase components but the functional consequences of many of these mutations still have to be experimentally demonstrated. The activity of twelve TERT and five TERC mutants, five of them identified in Spanish patients, has been analyzed. TERT and TERC mutants were expressed in VA-13 human cells that express low telomerase levels and the activity induced was analyzed. The production of reactive oxygen species, DNA oxidation and TRF2 association at telomeres, DNA damage response and cell apoptosis were determined. Most mutations presented decreased telomerase activity, as compared to wild-type TERT and TERC. In addition, the expression of several TERT and TERC mutants induced oxidative stress, DNA oxidation, DNA damage, decreased recruitment of the shelterin component TRF2 to telomeres and increased apoptosis. These observations might indicate that the increase in DNA damage and oxidative stress observed in cells from telomeropathy patients is dependent on their TERT or TERC mutations. Therefore, analysis of the effect of TERT and TERC mutations of unknown function on DNA damage and oxidative stress could be of great utility to determine the possible pathogenicity of these variants.

PMID:38641551 | PMC:PMC11031360 | DOI:10.1093/hmg/ddae015

J Biol Chem. 2024 Apr 17:107300. doi: 10.1016/j.jbc.2024.107300. Online ahead of print.

ABSTRACT

Integrin-mediated activation of the pro-fibrotic mediator transforming growth factor-β1 (TGF-β1), plays a critical role in idiopathic pulmonary fibrosis (IPF) pathogenesis. Galectin-3 is believed to contribute to the pathological wound healing seen in IPF, although its mechanism of action is not precisely defined. We hypothesised that galectin-3 potentiates TGF-β1 activation and/or signaling in the lung to promote fibrogenesis. We show that galectin-3 induces TGF-β1 activation in human lung fibroblasts (HLFs) and specifically that extracellular galectin-3 promotes oleoyl-L-α-lysophosphatidic acid sodium salt (LPA)-induced integrin-mediated TGF-β1 activation. Surface plasmon resonance (SPR) analysis confirmed that galectin-3 binds to αv integrins, αvβ1, αvβ5 and αvβ6 and to the TGFβRII subunit in a glycosylation-dependent manner. This binding is heterogeneous and not a 1:1 binding stoichiometry. Binding interactions were blocked by small molecule inhibitors of galectin-3 which target the carbohydrate recognition domain. Galectin-3 binding to β1 integrin was validated in vitro by co-immunoprecipitation in HLFs. Proximity ligation assays indicated galectin-3 and β1 integrin colocalize closely (≤40 nm) on the cell surface, that colocalization is increased by TGF-β1 treatment and blocked by galectin-3 inhibitors. In the absence of TGF-β1 stimulation, colocalization was detectable only in HLFs from IPF patients suggesting the proteins are inherently more closely associated in the disease state. Galectin-3 inhibitor treatment of precision cut lung slices from IPF patients reduced Col1a1, TIMP1 and HA secretion to a similar degree as TGF-β type I receptor inhibitor. These data suggest galectin-3 promotes TGF-β1 signaling and may induce fibrogenesis by interacting directly with components of the TGF-β1 signaling cascade.

PMID:38641066 | DOI:10.1016/j.jbc.2024.107300

Medicine (Baltimore). 2024 Apr 19;103(16):e37808. doi: 10.1097/MD.0000000000037808.

ABSTRACT

Immune checkpoint inhibitor pneumonitis (ICIP) is thought to be a self-limiting disease; however, an effective treatment option does not currently exist. This study aimed to determine the clinical efficacy of combination therapy with glucocorticoids and pirfenidone for ICIP related to programmed cell death protein-1 (PD-1) inhibitors. We conducted a retrospective analysis of 45 patients with advanced non-small cell lung cancer who developed ICIP following PD-1 inhibitor and albumin-bound paclitaxel or carboplatin treatment at our hospital. The PD-1 inhibitor was discontinued, and glucocorticoids were used alone or in combination with pirfenidone to treat ICIP. The relevant clinical data of these patients were collected and analyzed. Compared with the glucocorticoid alone group, the glucocorticoid-pirfenidone group showed significant improvement in forced vital capacity (FVC), carbon monoxide diffusing capacity [%], peripheral capillary oxygen saturation, and 6-minute walk distance (P < .05). There were benefits with respect to the St. George's Respiratory Questionnaire score and the recurrence rate of ICIP, but there was no significant difference between the 2 groups (P > .05). Adding pirfenidone to glucocorticoid treatment was shown to be safe and may be more beneficial than glucocorticoids alone for improving pulmonary interstitial lesions, reversing ICIP, and preventing its recurrence.

PMID:38640289 | PMC:PMC11029951 | DOI:10.1097/MD.0000000000037808

Bioorg Chem. 2024 Apr 16;147:107374. doi: 10.1016/j.bioorg.2024.107374. Online ahead of print.

ABSTRACT

The incidence of idiopathic pulmonary fibrosis (IPF) has been steadily increasing each year, posing significant challenges in its treatment. In this study, we conducted the design and synthesis of 23 new inhibitors that specifically target the TGF-β1/Smad3 pathway. Initially, we employed a cell model of TGF-β-induced pulmonary fibrosis, using cell survival rate and HYP expression as indicators to identify the potent ingredient 5aa, which demonstrated significant anti-pulmonary fibrosis activity. Subsequently, we induced mice with bleomycin (BLM) to establish an experimental animal model of pulmonary fibrosis, and evaluated the pharmacodynamics of 5aa in vivo against pulmonary fibrosis. The alterations in HYP and collagen levels in BLM-induced pulmonary fibrosis mice were analyzed using ELISA and immunohistochemistry techniques. The results indicated that compound 5aa effectively suppressed the fibrotic response induced by TGF-β1, inhibited the expression of the fibrotic marker α-SMA, and hindered the EMT process in NIH3T3 cells. Additionally, oral administration of 5aa demonstrated significant therapeutic effects in a mouse model of IPF, comparable to the established drug Nintedanib. Moreover, compound 5aa exhibited higher bioavailability in vivo compared to Nintedanib. These collective outcomes suggest that 5aa holds promise as a potential inhibitor of TGF-β1/Smad3 signaling for the treatment of IPF.

PMID:38636433 | DOI:10.1016/j.bioorg.2024.107374

Cell Mol Life Sci. 2024 Apr 18;81(1):187. doi: 10.1007/s00018-024-05219-x.

ABSTRACT

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.

PMID:38635081 | DOI:10.1007/s00018-024-05219-x