Idiopathic Pulmonary Fibrosis
Plasticity towards Rigidity: A Macrophage Conundrum in Pulmonary Fibrosis
Int J Mol Sci. 2022 Sep 28;23(19):11443. doi: 10.3390/ijms231911443.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a progressive, chronic, and ultimately fatal diffuse parenchymal lung disease. The molecular mechanisms of fibrosis in IPF patients are not fully understood and there is a lack of effective treatments. For decades, different types of drugs such as immunosuppressants and antioxidants have been tested, usually with unsuccessful results. Although two antifibrotic drugs (Nintedanib and Pirfenidone) are approved and used for the treatment of IPF, side effects are common, and they only slow down disease progression without improving patients' survival. Macrophages are central to lung homeostasis, wound healing, and injury. Depending on the stimulus in the microenvironment, macrophages may contribute to fibrosis, but also, they may play a role in the amelioration of fibrosis. In this review, we explore the role of macrophages in IPF in relation to the fibrotic processes, epithelial-mesenchymal transition (EMT), and their crosstalk with resident and recruited cells and we emphasized the importance of macrophages in finding new treatments.
PMID:36232756 | DOI:10.3390/ijms231911443
Role of Mesenchymal Stem Cells and Extracellular Vesicles in Idiopathic Pulmonary Fibrosis
Int J Mol Sci. 2022 Sep 23;23(19):11212. doi: 10.3390/ijms231911212.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial fibrotic disease that leads to disability and death within 5 years of diagnosis. Pulmonary fibrosis is a disease with a multifactorial etiology. The concept of aberrant regeneration of the pulmonary epithelium reveals the pathogenesis of IPF, according to which repeated damage and death of alveolar epithelial cells is the main mechanism leading to the development of progressive IPF. Cell death provokes the migration, proliferation and activation of fibroblasts, which overproduce extracellular matrix, resulting in fibrotic deformity of the lung tissue. Mesenchymal stem cells (MSCs) and extracellular vesicles (EVs) are promising therapies for pulmonary fibrosis. MSCs, and EVs derived from MSCs, modulate the activity of immune cells, inhibit the expression of profibrotic genes, reduce collagen deposition and promote the repair of damaged lung tissue. This review considers the molecular mechanisms of the development of IPF and the multifaceted role of MSCs in the therapy of IPF. Currently, EVs-MSCs are regarded as a promising cell-free therapy tool, so in this review we discuss the results available to date of the use of EVs-MSCs for lung tissue repair.
PMID:36232511 | DOI:10.3390/ijms231911212
Exosomal Micro-RNAs as Intercellular Communicators in Idiopathic Pulmonary Fibrosis
Int J Mol Sci. 2022 Sep 20;23(19):11047. doi: 10.3390/ijms231911047.
ABSTRACT
Communication between neighboring or distant cells is made through a complex network that includes extracellular vesicles (EVs). Exosomes, which are a subgroup of EVs, are released from most cell types and have been found in biological fluids such as urine, plasma, and airway secretions like bronchoalveolar lavage (BAL), nasal lavage, saliva, and sputum. Mainly, the cargo exosomes are enriched with mRNAs and microRNAs (miRNAs), which can be transferred to a recipient cell consequently modifying and redirecting its biological function. The effects of miRNAs derive from their role as gene expression regulators by repressing or degrading their target mRNAs. Nowadays, various types of research are focused on evaluating the potential of exosomal miRNAs as biomarkers for the prognosis and diagnosis of different pathologies. Nevertheless, there are few reports on their role in the pathophysiology of idiopathic pulmonary fibrosis (IPF), a chronic lung disease characterized by progressive lung scarring with no cure. In this review, we focus on the role and effect of exosomal miRNAs as intercellular communicators in the onset and progression of IPF, as well as discussing their potential utility as therapeutic agents for the treatment of this disease.
PMID:36232350 | DOI:10.3390/ijms231911047
Effect of Hypoxia in the Transcriptomic Profile of Lung Fibroblasts from Idiopathic Pulmonary Fibrosis
Cells. 2022 Sep 27;11(19):3014. doi: 10.3390/cells11193014.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is an aging-associated disease characterized by exacerbated extracellular matrix deposition that disrupts oxygen exchange. Hypoxia and its transcription factors (HIF-1α and 2α) influence numerous circuits that could perpetuate fibrosis by increasing myofibroblasts differentiation and by promoting extracellular matrix accumulation. Therefore, this work aimed to elucidate the signature of hypoxia in the transcriptomic circuitry of IPF-derived fibroblasts. To determine this transcriptomic signature, a gene expression analysis with six lines of lung fibroblasts under normoxia or hypoxia was performed: three cell lines were derived from patients with IPF, and three were from healthy donors, a total of 36 replicates. We used the Clariom D platform, which allows us to evaluate a huge number of transcripts, to analyze the response to hypoxia in both controls and IPF. The control's response is greater by the number of genes and complexity. In the search for specific genes responsible for the IPF fibroblast phenotype, nineteen dysregulated genes were found in lung fibroblasts from IPF patients in hypoxia (nine upregulated and ten downregulated). In this sense, the signaling pathways revealed to be affected in the pulmonary fibroblasts of patients with IPF may represent an adaptation to chronic hypoxia.
PMID:36230977 | DOI:10.3390/cells11193014
Functional Repercussions of Hypoxia-Inducible Factor-2α in Idiopathic Pulmonary Fibrosis
Cells. 2022 Sep 20;11(19):2938. doi: 10.3390/cells11192938.
ABSTRACT
Hypoxia and hypoxia-inducible factors (HIFs) are essential in regulating several cellular processes, such as survival, differentiation, and the cell cycle; this adaptation is orchestrated in a complex way. In this review, we focused on the impact of hypoxia in the physiopathology of idiopathic pulmonary fibrosis (IPF) related to lung development, regeneration, and repair. There is robust evidence that the responses of HIF-1α and -2α differ; HIF-1α participates mainly in the acute phase of the response to hypoxia, and HIF-2α in the chronic phase. The analysis of their structure and of different studies showed a high specificity according to the tissue and the process involved. We propose that hypoxia-inducible transcription factor 2a (HIF-2α) is part of the persistent aberrant regeneration associated with developing IPF.
PMID:36230900 | DOI:10.3390/cells11192938
Anti-Fibrotic Drug Nintedanib Inhibits CSF1R to Promote IL-4-associated Tissue Repair Macrophages
Am J Respir Cell Mol Biol. 2022 Oct 13. doi: 10.1165/rcmb.2022-0021OC. Online ahead of print.
ABSTRACT
Pro-fibrotic and pro-homeostatic macrophage phenotypes remain ill-defined, both in vivo and in vitro impeding successful development of drugs that reprogram macrophages as an attractive therapeutic approach to manage fibrotic disease. The goal to of this study was to reveal pro-fibrotic and pro-homeostatic macrophage phenotypes which could guide the design of new therapeutic approaches targeting macrophages to treat fibrotic disease. We used nintedanib, a broad kinase inhibitor, approved for idiopathic pulmonary fibrosis (IPF) to dissect lung macrophage phenotypes during fibrosis-linked inflammation by combining in vivo and in vitro bulk and single cell RNA sequencing approaches. In the bleomycin model, nintedanib drove expression of IL-4/IL-13 associated genes important for tissue regeneration and repair at early and late time points in lung macrophages. These findings were replicated in vitro in mouse primary bone marrow derived macrophages exposed to IL-4/IL-13 and nintedanib. In addition, nintedanib promoted expression of IL-4/IL-13 pathway genes in human macrophages in vitro. The molecular mechanism was connected to inhibition of the CSF1 receptor (CSF1R) in both human and mouse macrophages. Moreover, nintedanib counterbalanced the effects of TNF on IL-4/IL-13 in macrophages to promote expression of IL-4/IL-13 regulated tissue repair genes in fibrotic contexts in vivo and in vitro. Our study demonstrates the one of nintedanib's anti-fibrotic mechanisms is to increase IL-4 signaling in macrophages through inhibition of CSF1 receptor resulting in promotion of tissue repair phenotypes.
PMID:36227799 | DOI:10.1165/rcmb.2022-0021OC
Acute toxicological study: EZY-1 with potent therapeutic effects of idiopathic pulmonary fibrosis and its mechanisms
J Food Biochem. 2022 Oct 13:e14483. doi: 10.1111/jfbc.14483. Online ahead of print.
ABSTRACT
EZY-1 is an antifibrosis peptide purified from Eucheuma. In this study, we explored the acute toxicology of EZY-1 and the signaling pathways involved in its antifibrotic role. The mouse model of pulmonary fibrosis was induced by bleomycin. Pathological changes in lung tissue could be effectively inhibited by EZY-1. Acute toxicity and cell proliferation tests indicated that EZY-1 had no apparent toxicity to mice and cells. We identified proteins that could bind directly to EZY-1 in vitro on the basis of liquid chromatography-tandem mass spectrometry and bioinformatics analysis. EZY-1 inhibited pulmonary fibrosis via Wnt/β-catenin, transforming growth factor (TGF)-β/Smad, phosphoinositide 3-kinase/protein kinase B/ mammalian target of rapamycin, and activator of transcription 3 and Janus kinase 2/signal transducer pathways. A transwell micropore experiment showed that EZY-1 could inhibit cell migration and invasion. Western blotting analysis on transforming growth factor-β1 (TGF-β1)-induced A549 pulmonary fibrosis cell model suggested that EZY-1 could downregulate p-Smad3 (Ser423/Ser425), Smad4, β-catenin, vimentin, and N-cadherin expression. ELISA showed that EZY-1 could inhibit collagen-I secretion. EZY-1 alleviated idiopathic pulmonary fibrosis (IPF) through regulating TGF-β/Smad pathways, epithelial-mesenchymal transition processes, and collagen secretion, which provides a potential foundation for theoretical development of EZY-1 as a potential drug against IPF. PRACTICAL APPLICATIONS: We isolated a new 16-amino-acid peptide derived from the polypeptide extract of Eucheuma, named EZY-1. In vitro and in vivo assays show peptide EZY-1 is safe. The EZY-1 peptide alleviates IPF at lower doses than pirfenidone. EZY-1 alleviated idiopathic pulmonary fibrosis (IPF) through regulating TGF-β/Smad pathways, epithelial-mesenchymal transition (EMT) processes, and collagen secretion, which provides a theoretical basis for the development of EZY-1 as a potential drug against IPF.
PMID:36226766 | DOI:10.1111/jfbc.14483
Pulmonary hypertension in patients with interstitial lung disease: a tool for early detection
Pulm Circ. 2022 Oct 1;12(4):e12141. doi: 10.1002/pul2.12141. eCollection 2022 Oct.
ABSTRACT
Pulmonary hypertension (PH) complicates the treatment of interstitial lung disease (ILD) patients resulting in poor functional status and worse outcomes. Early recognition of PH in ILD is important for initiating therapy and considering lung transplantation. However, no standard exists regarding which patients to screen for PH-ILD or the optimal method to do so. The aim of this study was to create a risk assessment tool that could reliably predict PH in ILD patients. We developed a PH-ILD Detection tool that incorporated history, exam, 6-min walk distance, diffusion capacity for carbon monoxide, chest imaging, and cardiac biomarkers to create an eight-component score. This tool was analyzed retrospectively in 154 ILD patients where each patient was given a score ranging from 0 to 12. The sensitivity (SN) and specificity (SP) of the PH-ILD Detection tool and an area-under-the-curve (AUC) were calculated. In this cohort, 74 patients (48.1%) had PH-ILD. A score of ≥6 on the PH-ILD Detection tool was associated with a diagnosis of PH-ILD (SN: 86.5%; SP: 86.3%; area-under-the-curve: 0.920, p < 0.001). The PH-ILD Detection tool provides high SN and SP for detecting PH in ILD patients. With confirmation in larger cohorts, this tool could improve the diagnosis of PH in ILD and may suggest further testing with right heart catheterization and earlier intervention with inhaled treprostinil and/or lung transplant evaluation.
PMID:36225536 | PMC:PMC9531548 | DOI:10.1002/pul2.12141
Pim-1 Kinase is a Positive Feedback Regulator of the Senescent Lung Fibroblast Inflammatory Secretome
Am J Physiol Lung Cell Mol Physiol. 2022 Oct 12. doi: 10.1152/ajplung.00023.2022. Online ahead of print.
ABSTRACT
Cellular senescence is emerging as a driver of idiopathic pulmonary fibrosis (IPF), a progressive and fatal disease with limited effective therapies. The senescence-associated secretory phenotype (SASP), involving the release of inflammatory cytokines and profibrotic growth factors by senescent cells, is thought to be a product of multiple cell types in IPF, including lung fibroblasts. NF-κB is a master regulator of the SASP, and its activity depends on the phosphorylation of p65/RelA. The purpose of this study was to assess the role of Pim-1 kinase as a driver of NF-κB-induced production of inflammatory cytokines from low-passage IPF fibroblast cultures displaying markers of senescence. Our results demonstrate that Pim-1 kinase phosphorylates p65/RelA, activating NF-κB activity and enhancing IL-6 production, which in turn amplifies expression of PIM1, generating a positive feedback loop. Additionally, targeting Pim-1 kinase with a small molecule inhibitor dramatically inhibited the expression of a broad array of cytokines and chemokines in IPF-derived fibroblasts. Furthermore, we provide evidence that Pim-1 overexpression in low-passage human lung fibroblasts is sufficient to drive premature senescence, in vitro. These findings highlight the therapeutic potential of targeting Pim-1 kinase to reprogram the secretome of senescent fibroblasts and halt IPF progression.
PMID:36223640 | DOI:10.1152/ajplung.00023.2022
Oil Red O Staining of Pulmonary Macrophages in Bronchoalveolar Lavage Specimens Is Not Specific for Vaping-Associated Lung Injury
Am J Clin Pathol. 2022 Oct 5:aqac118. doi: 10.1093/ajcp/aqac118. Online ahead of print.
ABSTRACT
OBJECTIVES: Oil Red O (ORO) positivity in bronchoalveolar lavage (BAL) fluid macrophages in the setting of e-cigarette, or vaping, product use-associated acute lung injury (EVALI) has been frequently requested by clinicians based on rare reports and subsequent US Centers for Disease Control and Prevention guidelines. The aim of this study was to determine the specificity of ORO staining in BAL specimens with disease states other than EVALI.
METHODS: Consecutive BAL specimens (October-December 2019) were stained with ORO. The lipid-laden macrophage index (LLMI) was calculated for each case.
RESULTS: We studied BAL samples from 50 patients. Indications for BAL were surveillance bronchoscopy for lung transplantation (27/50), suspected infection (12/50), sarcoidosis/suspected sarcoidosis (3/50), nodules or ground-glass opacities (3/50), hemoptysis (2/50), asthma or eosinophilic pneumonia (2/50), and idiopathic pulmonary fibrosis (1/50). ORO staining was seen in BAL fluid macrophages in 45 of 50 cases (focal in 18, moderate in 23, diffuse in 4); LLMI ranged from 0 to 218. Using a threshold of LLMI of 85 or higher as positive, ORO was positive in 7 of 50 (14%) cases (range, 85-218).
CONCLUSIONS: ORO staining in BAL fluid macrophages is not specific for EVALI. Even when an LLMI of 85 or higher is used as a threshold for positivity, ORO positivity occurs in a significant subset of non-vaping-related cases.
PMID:36222561 | DOI:10.1093/ajcp/aqac118
Increased frequency of angiotensin converting enzyme D allele in Chinese Han patients with idiopathic pulmonary fibrosis: A systematic review and meta-analysis
Medicine (Baltimore). 2022 Oct 7;101(40):e30942. doi: 10.1097/MD.0000000000030942.
ABSTRACT
BACKGROUND: To explore the association between Angiotensin Converting Enzyme (ACE) insert(I)/defect(D) gene polymorphism and the susceptibility to idiopathic pulmonary fibrosis (IPF).
METHODS: Searching PubMed, EMbase, CENTRAL, MEDLINE, CBM, China National Knowledge Infrastructure, WanFang Database and VIP Chinese Science database through a computer and collect the literature from China and foreign countries published before January 22, 2022. Screen the literatures and extract data such as first author, year of publication, diagnostic criteria and gene frequency, and draw a funnel chart and perform Begg's Test and Egger's test to evaluate publication bias. The influence analysis was performed for heterogeneous results and at the same time, the trial sequential analysis (TSA) was also conducted to confirm the robustness of the meta-analysis results. Registration number: CRD42021259341.
RESULTS: There were a total of 4 literatures (4 studies conducted in the Chinese Han population), and a total of 292 IPF patients and 351 healthy controls were included in this study. The results showed that in the Chinese Han population, the ACE I/D gene polymorphism was associated with the susceptibility of IPF (D vs I: [odds ratio, OR] = 0.53, 95% confidence interval [95%CI] [0.42, 0.67], P < .00001; DD vs II: [OR] = 0.37, 95%CI [0.24, 0.57], P < .00001; DD vs II + ID:[OR] = 0.30, 95%CI [0.21, 0.43], P < .00001), and the angiotensin II (Ang Ⅱ) level of IPF patients was higher than that of the control group (mean difference [MD] = 14.29, 95%CI [11.20,17.37], P < .00001).The TSA also confirmed that D allele was closely related to the susceptibility of IPF.
CONCLUSION: In the Chinese Han population, the D allele of the ACE I/D gene polymorphism is associated with the susceptibility of IPF.
PMID:36221416 | DOI:10.1097/MD.0000000000030942
The potential benefit of endothelin receptor antagonists' therapy in idiopathic pulmonary fibrosis: A meta-analysis of results from randomized controlled trials
Medicine (Baltimore). 2022 Oct 7;101(40):e29981. doi: 10.1097/MD.0000000000029981.
ABSTRACT
BACKGROUND: Fibrotic diseases take a very heavy toll in terms of morbidity and mortality equal to or even greater than that caused by metastatic cancer. This meta-analysis aimed to evaluate the effect of endothelin receptor antagonists on idiopathic pulmonary fibrosis.
METHOD: A systematic search of the clinical trials from the Medline, Google Scholar, Cochrane Library, and PubMed electronic databases was performed. Stata version 12.0 statistical software (Stata Crop LP, College Station, TX) was adopted as statistical software.
RESULT: A total of 5 studies, which included 1500 participants. Our analysis found there is no significant difference between using the endothelin receptor antagonists' group and placebo groups regarding the lung function via estimating both the change of forced vital capacity from baseline and DLco index. Exercise capacity and serious adverse effects are taken into consideration as well; however, there is still no significant change between the 2 groups.
CONCLUSION: This meta-analysis provides insufficient evidence to support that endothelin receptor antagonists' administration provides a benefit among included participants who encounter idiopathic pulmonary fibrosis.
PMID:36221345 | DOI:10.1097/MD.0000000000029981
The FoxP1 gene regulates lung function, production of matrix metalloproteinases and inflammatory mediators, and viability of lung epithelia
Respir Res. 2022 Oct 11;23(1):281. doi: 10.1186/s12931-022-02213-4.
ABSTRACT
BACKGROUND: Genes involved in lung development may become dysregulated in adult life and contribute to the pathogenesis of lung diseases. Multiple genes regulate lung development, including Forkhead box protein P1-4 (FoxP1-4).
METHODS: We examined the association between variants in the FoxP1-4 genes and lung function using data from a GWAS that included close to 400,000 individuals and 20 million SNPs.
RESULTS: More than 100 variants in the FoxP1 gene, but none in the FoxP2-4 genes, are associated with lung function. The sentinel variant in the FoxP1 gene associated with FEV1 was rs1499894 (C > T), while the sentinel variant in the FoxP1 gene associated with FVC was rs35480566 (A > G). Those with the T allele instead of the C allele for rs1499894, or the G allele instead of the A allele for rs35480566 had increased FoxP1 mRNA levels in transcriptomic data, higher FEV1 and FVC, and reduced odds of being diagnosed with idiopathic pulmonary fibrosis. Further, knockdown of FoxP1 in lung epithelial cells by RNA interference led to increased mRNA levels for matrix metalloproteinases 1, 2, 3 and pro-inflammatory cytokines IL-6 & IL-8, as well as reduced cell viability after exposure to cigarette smoke-all processes implicated in the pathogenesis of COPD and IPF.
CONCLUSIONS: Our results suggest that the protein encoded by the FoxP1 gene may protect against the development of COPD and IPF. A causal role for FoxP1 in the pathogenesis of COPD and IPF may warrant further investigation, and FoxP1 may be a novel therapeutic target for these lung disorders.
PMID:36221131 | DOI:10.1186/s12931-022-02213-4
Idiopathic pulmonary fibrosis: Diagnosis, biomarkers and newer treatment protocols
Dis Mon. 2022 Oct 8:101484. doi: 10.1016/j.disamonth.2022.101484. Online ahead of print.
ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung condition marked by lung scarring that progresses over time and with usual interstitial pneumonia histology (UIP). It is linked to a worsening cough, dyspnea, and a worse quality of life. Around 3 million persons worldwide suffer from IPF, and the prevalence rises sharply with advancing age. The detection of the UIP pattern, generally using high-resolution CT; lung biopsy may be necessary in certain individuals; the diagnostic approach also includes the elimination of other interstitial lung illnesses or overlapping problems. The UIP pattern is mostly bilateral, peripheral, and basal, with clusters of subpleural cystic airspaces and reticular alterations linked to traction bronchiectasis. Although there are still many uncertainties about how to define susceptibility, it is believed that the molecular mechanisms causing IPF reflect an abnormal reparative response to repeated alveolar epithelial damage in an aging genetically sensitive individual. With the availability of two pharmacotherapeutic drugs, pirfenidone and nintedanib, that slow physiological advancement and potentially increase progression-free survival, significant progress has been made in our knowledge of the clinical treatment of IPF. The goal of current research is to develop early biomarkers for IPF that may include circulating variables, demographic information, and imaging data.
PMID:36220705 | DOI:10.1016/j.disamonth.2022.101484
Antifibrotic therapy and its indications for interstitial pulmonary fibrosis
Vnitr Lek. 2022 Fall;68(4):212-215.
ABSTRACT
Idiopathic pulmonary fibrosis and chronic fibrotic interstitial lung disease with progressive phenotype are characterized by fibrotic lung parenchyma. Current antifibrotic treatment does not affect pre-existing lung parenchyma fibrosis, but prevents fibrosis progression and reduces mortality by reducing fibrotization. This work summarizes fibrotic lung processes and their treatment options.
PMID:36220417
Integrative analyses for the identification of idiopathic pulmonary fibrosis-associated genes and shared loci with other diseases
Thorax. 2022 Oct 10:thoraxjnl-2021-217703. doi: 10.1136/thorax-2021-217703. Online ahead of print.
ABSTRACT
BACKGROUND: Although genome-wide association studies (GWAS) have identified many genomic regions associated with idiopathic pulmonary fibrosis (IPF), the causal genes and functions remain largely unknown. Many single-cell expression data have become available for IPF, and there is increasing evidence suggesting a shared genetic basis between IPF and other diseases.
METHODS: We conducted integrative analyses to improve the power of GWAS. First, we calculated global and local genetic correlations to identify IPF genetically associated traits and local regions. Then, we prioritised candidate genes contributing to local genetic correlation. Second, we performed transcriptome-wide association analysis (TWAS) of 44 tissues to identify candidate genes whose genetically predicted expression level is associated with IPF. To replicate our findings and investigate the regulatory role of the transcription factors (TF) in identified candidate genes, we first conducted the heritability enrichment analysis in TF binding sites. Then, we examined the enrichment of the TF target genes in cell-type-specific differentially expressed genes (DEGs) identified from single-cell expression data of IPF and healthy lung samples.
FINDINGS: We identified 12 candidate genes across 13 genomic regions using local genetic correlation, including the POT1 locus (p value=0.00041), which contained variants with protective effects on lung cancer but increasing IPF risk. We identified another 13 novel genes using TWAS. Two TFs, MAFK and SMAD2, showed significant enrichment in both partitioned heritability and cell-type-specific DEGs.
INTERPRETATION: Our integrative analysis identified new genes for IPF susceptibility and expanded the understanding of the complex genetic architecture and disease mechanism of IPF.
PMID:36216496 | DOI:10.1136/thorax-2021-217703
Identification and immune characteristics of molecular subtypes related to fatty acid metabolism in idiopathic pulmonary fibrosis
Front Nutr. 2022 Sep 23;9:992331. doi: 10.3389/fnut.2022.992331. eCollection 2022.
ABSTRACT
BACKGROUND: Although fatty acid metabolism has been confirmed to be involved in the pathological process of idiopathic pulmonary fibrosis (IPF), systematic analyses on the immune process mediated by fatty acid metabolism-related genes (FAMRGs) in IPF remain lacking.
METHODS: The gene expression data of 315 patients with IPF were obtained from Gene Expression Omnibus database and were divided into the training and verification sets. The core FAMRGs of the training set were identified through weighted gene co-expression network analysis. Then, the fatty acid metabolism-related subtypes in IPF were identified on the basis of k-means unsupervised clustering. The scores of fatty acid metabolism and the expression of the fibrosis biomarkers in different subtypes were compared, and functional enrichment analysis was carried out on the differentially expressed genes between subtypes. A random forest model was used to select important FAMRGs as diagnostic markers for distinguishing between subtypes, and a line chart model was constructed and verified by using other datasets and rat models with different degrees of pulmonary fibrosis. The difference in immune cell infiltration among subtypes was evaluated with CIBERSORT, and the correlation between core diagnostic markers and immune cells were analyzed.
RESULTS: Twenty-four core FAMRGs were differentially expressed between the training set and normal samples, and IPF was divided into two subtypes. Significant differences were observed between the two subtypes in biological processes, such as linoleic acid metabolism, cilium movement, and natural killer (NK) cell activation. The subtype with high fatty acid metabolism had more severe pulmonary fibrosis than the other subtype. A reliable construction line chart model based on six diagnostic markers was constructed, and ABCA3 and CYP24A1 were identified as core diagnostic markers. Significant differences in immune cell infiltration were found between the two subtypes, and ABCA3 and CYP24A1 were closely related to NK cells.
CONCLUSION: Fatty acid metabolism and the immune process that it mediates play an important role in the occurrence and development of IPF. The analysis of the role of FAMRGs in IPF may provide a new potential therapeutic target for IPF.
PMID:36211517 | PMC:PMC9537386 | DOI:10.3389/fnut.2022.992331
Identification and validation of autophagy-related gene expression for predicting prognosis in patients with idiopathic pulmonary fibrosis
Front Immunol. 2022 Sep 20;13:997138. doi: 10.3389/fimmu.2022.997138. eCollection 2022.
ABSTRACT
BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fatal fibrotic pulmonary disease with unknow etiology. Owing to lack of reliable prognostic biomarkers and effective treatment measures, patients with IPF usually exhibit poor prognosis. The aim of this study is to establish a risk score prognostic model for predicting the prognosis of patients with IPF based on autophagy-related genes.
METHODS: The GSE70866 dataset was obtained from the gene expression omnibus (GEO) database. The autophagy-related genes were collected from the Molecular Signatures Database (MSigDB). Gene enrichment analysis for differentially expressed genes (DEGs) was performed to explore the function of DEGs. Univariate, least absolute shrinkage and selection operator (LASSO), as well as multivariate Cox regression analyses were conducted to identify a multi-gene prognostic model. Receiver operating characteristic (ROC) curve was applied to assess the prediction accuracy of the model. The expression of genes screened from the prognostic model was validated in clinical samples and human lung fibroblasts by qPCR and western blot assays.
RESULTS: Among the 514 autophagy-related genes, a total of 165 genes were identified as DEGs. These DEGs were enriched in autophagy-related processes and pathways. Based on the univariate, LASSO, and multivariate Cox regression analyses, two genes (MET and SH3BP4) were included for establishing the risk score prognostic model. According to the median value of the risk score, patients with IPF were stratified into high-risk and low-risk groups. Patients in high-risk group had shorter overall survival (OS) than low-risk group in both training and test cohorts. Multivariate regression analysis indicated that prognostic model can act as an independent prognostic indicator for IPF. ROC curve analysis confirmed the reliable predictive value of prognostic model. In the validation experiments, upregulated MET expression and downregulated SH3BP4 expression were observed in IPF lung tissues and TGF-β1-activated human lung fibroblasts, which is consistent with results from microarray data analysis.
CONCLUSION: These findings indicated that the risk score prognostic model based on two autophagy-related genes can effectively predict the prognosis of patients with IPF.
PMID:36211385 | PMC:PMC9533718 | DOI:10.3389/fimmu.2022.997138
Beyond What Meets the Eye: Artificial Intelligence in the Diagnosis of Idiopathic Pulmonary Fibrosis
Chest. 2022 Oct;162(4):734-735. doi: 10.1016/j.chest.2022.04.152.
NO ABSTRACT
PMID:36210098 | DOI:10.1016/j.chest.2022.04.152
Clinical features and survival analysis of microscopic polyangiitis-associated interstitial lung disease:a retrospective study of 28 patients
Zhonghua Jie He He Hu Xi Za Zhi. 2022 Oct 12;45(10):1022-1030. doi: 10.3760/cma.j.cn112147-20220208-00097.
ABSTRACT
Objective: To explore the clinical features, laboratory examination and imaging features of microscopic polyangiitis (MPA)-associated interstitial lung disease (ILD), and to perform survival analysis. Methods: The records of 28 patients with MPA-ILD who were treated at the Affiliated Hospital of Medical School of Ningbo University were reviewed retrospectively from August 2014 to November 2021. The patients' clinical features, laboratory parameters, pulmonary function test, echocardiography, chest CT scan findings and therapeutic regimen were analyzed, and the relevant data were statistically analyzed. Results: There were 18 males and 10 females, with an average age of (70.1±9.3) years. Among them, 13 patients had a history of smoking. The main clinical manifestations were cough (14/28), fever (12/28), chest tightness, shortness of breath (12/28) and hemoptysis (3/28). Sixteen patients had renal involvement, and 78.57% (22/28) and 89.28% (25/28) of the patients had elevated C-reactive protein (CRP) and ESR respectively. Sixteen (16/28) patients had increased rheumatoid factor (RF), and the positive rate of myeloperoxidase antineutrophil cytoplasmic antibodies (MPO-ANCA) was 82.12% (23/28). 96.43% (27/28) of ILDs were diagnosed before or at the same time as MPA. The chest radiological pattern was mainly usual interstitial pneumonia (UIP) or UIP-like (15/28), followed by nonspecific interstitial pneumonia (NSIP) (8/28). Compared with non-UIP-like patients, UIP or UIP-like patients were older (P=0.018), and had higher serum LDH level (P=0.041), but serum creatinine level was significantly lower (P=0.041). Univariate and multivariate survival analysis showed that inappropriate treatment (HR=9.81, 95%CI: 1.68-57.29, P=0.011) and elevated serum LDH (HR=4.11, 95%CI: 0.99-17.00, P=0.051) were independent risk factors for shortened survival of MPA-ILD, while elevated RF (HR=0.22, 95%CI: 0.06-0.91, P=0.037) was a protective factor for prolonged survival. Conclusions: MPA-ILD patients had fewer systemic vasculitis symptoms. Most of the ILD patients were diagnosed before or at the same time as MPA. The chest radiological pattern was mainly UIP or UIP-like, followed by NSIP. Early use of glucocorticoids combined with immunosuppressant or rituximab could improve the survival rate of MPA-ILD. The elevated serum LDH was an independent risk factor for shortened survival of MPA-ILD, while elevated RF was a protective factor for prolonged survival.
PMID:36207959 | DOI:10.3760/cma.j.cn112147-20220208-00097