Ann Palliat Med. 2021 Aug 12:apm-21-1836. doi: 10.21037/apm-21-1836. Online ahead of print.

ABSTRACT

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a life-threatening disease, the progression of which current drug therapy cannot reverse. This study analyzed current research hotspots and future research trends in IPF through bibliometric methods, with the aim of providing a reference for new therapeutic strategies.

METHODS: Publications on IPF obtained from the Web of Science Core Collection database, The Literature Metrology Online Analysis Platform, and CiteSpace were used to analyze publication characteristics. VOSviewer was used to conduct keywords co-occurrence analysis and analyze research hotspots.

RESULTS: A total of 7,016 publications related to IPF were identified from 2011 to 2020. The most contributions were from the USA and the five research institutions with the largest number of publications were all from that country. The American Journal of Respiratory and Critical Care Medicine was the most cited journal and had an incontrovertible academic impact with five of the top 10 high-cited references published in this journal. G Raghu was the academic authority in this domain in terms of both the number of publications and the most citations. By analyzing keywords, we identified three IPF research hotspot clusters, which are "clinical research", "pathogenesis research" and "diagnosis research" respectively.

DISCUSSION: We evaluated all publications concerning IPF research in the past decade through bibliometric analysis. The current research hotspot in this field is drug therapy for the condition using nintedanib and pirfenidone. Future research will focus on conducting multi-center randomized controlled trials to explore and evaluate new therapeutic drugs for IPF. It is hoped that this study can provide information and data support for further research and the development of new therapeutic drugs.

PMID:34455797 | DOI:10.21037/apm-21-1836

Respir Med. 2021 Aug 21;187:106581. doi: 10.1016/j.rmed.2021.106581. Online ahead of print.

ABSTRACT

OBJECTIVES: The detection of myositis autoantibodies (MA) in patients with interstitial lung disease (ILD) has major implications for diagnosis and management, especially amyopathic and forme frustes of idiopathic inflammatory myositis-associated ILD (IIM-ILD). Use of the MA line immunoblot assay (MA-LIA) in non-rheumatological cohorts remains unvalidated. We assessed the diagnostic performance of the MA-LIA and explored combined models with clinical variables to improve identification of patients with IIM-ILD.

METHODS: Consecutive patients referred to a specialist ILD clinic, with ILD-diagnosis confirmed at multidisciplinary meeting, and MA-LIA performed within six months of baseline were included. Pre-specified MA-LIA thresholds were evaluated for IIM-ILD diagnosis.

RESULTS: A total 247 ILD patients were included (IIM-ILD n = 12, non-IIM connective tissue disease-associated ILD [CTD-ILD] n = 52, idiopathic interstitial pneumonia [IIP] n = 115, other-ILD n = 68). Mean age was 64.8 years, with 45.3% female, mean FVC 75.5% and DLCO 59.2% predicted. MA were present in 13.8% overall and 83.3% of IIM-ILD patients. The most common MA in IIM-ILD and non-IIM ILD patients were anti-Jo-1 (prevalence 40%) and anti-PMScl (29.2%) autoantibodies respectively. The pre-specified low-positive threshold (>10 signal intensity) had the highest discriminative capacity for IIM-ILD (AUC 0.86). Combining MA-LIA with age, gender, clinical CTD-manifestations and an overlap non-specific interstitial pneumonia/organising pneumonia pattern on HRCT improved discrimination for IIM-ILD (AUC 0.96).

CONCLUSION: The MA-LIA is useful to support a diagnosis of IIM-ILD as a complement to multi-disciplinary ILD assessment. Clinical interpretation is optimised by consideration of the strength of the MA-LIA result together with clinical and radiological features of IIM-ILD.

PMID:34454312 | DOI:10.1016/j.rmed.2021.106581

Medicina (B Aires). 2021;81(4):671-673.

NO ABSTRACT

PMID:34453820

Interact Cardiovasc Thorac Surg. 2021 Aug 28:ivab237. doi: 10.1093/icvts/ivab237. Online ahead of print.

ABSTRACT

A best evidence topic was written according to a structured protocol. The question addressed was: 'Does continuation of antifibrotics before lung transplantation (LTx) influence post-transplant outcomes in patients with idiopathic pulmonary fibrosis (IPF) with regard to mortality, bronchial anastomotic dehiscence, reoperation for bleeding and wound complications, primary graft dysfunction or longer-term survival and allograft rejection?' A total of 261 articles were found using the reported search strategy, of which 7 represented the best evidence to answer the clinical question. Six out of 7 studies demonstrated equivalent post-transplant survival among IPF patients on antifibrotics before LTx compared with controls. Five out of 6 studies showed no increase in the risk of major bleeding, wound or bronchial anastomotic complications. One bi-institutional study found a higher incidence of early bronchial anastomotic dehiscence, but this difference was not statistically significant after longer term follow-up. In a study that only included IPF patients who underwent single LTx, a lower incidence of grade 3 primary graft dysfunction was reported in the antifibrotic group compared with controls. Overall, to date, only small (N < 40 in the antifibrotic group), non-risk-adjusted, retrospective observational studies have been published. Notwithstanding, the summation of available evidence suggests that, in IPF patients, continuation of antifibrotic therapy before LTx is likely safe, and the rates of perioperative bleeding, wound or bronchial anastomotic complications, as well as 30-day and 1-year survival, are similar to patients not on antifibrotics before LTx.

PMID:34453531 | DOI:10.1093/icvts/ivab237

Pharmaceuticals (Basel). 2021 Aug 20;14(8):819. doi: 10.3390/ph14080819.

ABSTRACT

The discovery of antifibrotic agents have resulted in advances in the therapeutic management of idiopathic pulmonary fibrosis (IPF). Currently, nintedanib and pirfenidone have become the basis of IPF therapy based on the results of large randomized clinical trials showing their safety and efficacy in reducing disease advancement. However, the goal of completely halting disease progress has not been reached yet. Administering nintedanib with add-on pirfenidone is supposed to enhance the therapeutic benefit by simultaneously acting on two different pathogenic pathways. All this becomes more important in the context of the ongoing global pandemic of coronavirus disease 2019 (COVID-19) because of the fibrotic consequences following SARS-CoV-2 infection in some patients. However, little information is available about their drug-drug interaction, which is important mainly in polymedicated patients. The aim of this review is to describe the current management of progressive fibrosing interstitial lung diseases (PF-ILDs) in general and of IPF in particular, focusing on the pharmacokinetic drug-drug interactions between these two drugs and their relationship with other medications in patients with IPF.

PMID:34451916 | DOI:10.3390/ph14080819

Pharmaceuticals (Basel). 2021 Aug 17;14(8):807. doi: 10.3390/ph14080807.

ABSTRACT

At the end of 2019, a highly contagious infection began its ominous conquest of the world. It was soon discovered that the disease was caused by a novel coronavirus designated as SARS-CoV-2, and the disease was thus abbreviated to COVID-19 (COVID). The global medical community has directed its efforts not only to find effective therapies against the deadly pathogen but also to combat the concomitant complications. Two of the most common respiratory manifestations of COVID are a significant reduction in the diffusing capacity of the lungs (DLCO) and the associated pulmonary interstitial damage. One year after moderate COVID, the incidence rate of impaired DLCO and persistent lung damage still exceeds 30%, and one-third of the patients have severe DLCO impairment and fibrotic lung damage. The persistent respiratory complications may cause substantial population morbidity, long-term disability, and even death due to the lung fibrosis progression. The incidence of COVID-induced pulmonary fibrosis caused by COVID can be estimated based on a 15-year observational study of lung pathology after SARS. Most SARS patients with fibrotic lung damage recovered within the first year and then remained healthy; however, in 20% of the cases, significant fibrosis progression was found in 5-10 years. Based on these data, the incidence rate of post-COVID lung fibrosis can be estimated at 2-6% after moderate illness. What is worse, there are reasons to believe that fibrosis may become one of the major long-term complications of COVID, even in asymptomatic individuals. Currently, despite the best efforts of the global medical community, there are no treatments for COVID-induced pulmonary fibrosis. In this review, we analyze the latest data from ongoing clinical trials aimed at treating post-COVID lung fibrosis and analyze the rationale for the current drug candidates. We discuss the use of antifibrotic therapy for idiopathic pulmonary fibrosis, the IN01 vaccine, glucocorticosteroids as well as the stromal vascular fraction for the treatment and rehabilitation of patients with COVID-associated pulmonary damage.

PMID:34451904 | DOI:10.3390/ph14080807

Pharmaceuticals (Basel). 2021 Jul 31;14(8):755. doi: 10.3390/ph14080755.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a disease characterized by extensive fibrosis of the lung tissue. Wnt5a expression was observed to be upregulated in IPF and suggested to be involved in the progression of the disease. Interestingly, smooth muscle cells (SMC) are a major source of Wnt5a in IPF patients. However, no study has been conducted until now to investigate the precise role of smooth muscle-derived Wnt5a in IPF. Here, we used the bleomycin-induced lung fibrosis model in a conditional gene-deficient mouse, where the Wnt5a gene was excised from SMC. We show here that the excision of the Wnt5a gene in SMC led to significantly improved health conditions with minimized weight loss and improved lung function. This improvement was based on a significantly lower deposition of collagen in the lung with a reduced number of fibrotic foci in lung parenchyma. Furthermore, the bleomycin-induced cellular infiltration into the airways was not altered in the gene-deficient mice compared with wild-type mice. Thus, we demonstrate that the Wnt5a expression of SMC of the airways leads to aggravated fibrosis of the lung with poor clinical conditions. This aggravation was not an influence in the bleomycin-induced inflammatory processes but on the development of fibrotic foci in lung parenchyma and the deposition of collagen.

PMID:34451852 | DOI:10.3390/ph14080755

Respirology. 2021 Aug 26. doi: 10.1111/resp.14137. Online ahead of print.

ABSTRACT

BACKGROUND AND OBJECTIVE: Patients with idiopathic pulmonary fibrosis (IPF) have reduced levels of daily physical activity (DPA); however, little is known about how DPA changes as disease progresses. We aimed to (i) describe change in DPA over 12 months, (ii) analyse its association with conventional markers of disease severity and quality of life and (iii) assess DPA as a prognostic tool.

METHODS: A total of 54 patients with IPF had DPA monitored at baseline and at 6 and 12 months with a SenseWear armband for 7 consecutive days. Participants completed the Hospital Anxiety and Depression scale, St George's Respiratory Questionnaire and Leicester Cough Questionnaire at each time point and provided clinical data including forced vital capacity (FVC), diffusion capacity of carbon monoxide and 6-min walk distance (6MWD).

RESULTS: Baseline and 12-month daily step count (DSC) were 3887 (395) and 3326 (419), respectively. A significant reduction in DSC (mean = 645 [260], p = 0.02) and total energy expenditure (mean = 486 kJ [188], p = 0.01) was demonstrated at 12 months. The decline in DSC over 12 months was proportionally larger than decline in lung function. Annual change in DPA had weak to moderate correlation with annual change in FVC % predicted and 6MWD (range r = 0.34-0.45). Change in physical activity was not associated with long-term survival.

CONCLUSION: In IPF, decline in DPA over 12 months is significant and disproportionate to decline in pulmonary physiology and may be a useful tool for assessment of disease progression.

PMID:34448321 | DOI:10.1111/resp.14137

Int J Mol Sci. 2021 Aug 19;22(16):8952. doi: 10.3390/ijms22168952.

ABSTRACT

Interstitial lung diseases (ILDs) that are known as diffuse parenchymal lung diseases (DPLDs) lead to the damage of alveolar epithelium and lung parenchyma, culminating in inflammation and widespread fibrosis. ILDs that account for more than 200 different pathologies can be divided into two groups: ILDs that have a known cause and those where the cause is unknown, classified as idiopathic interstitial pneumonia (IIP). IIPs include idiopathic pulmonary fibrosis (IPF), non-specific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP) known also as bronchiolitis obliterans organizing pneumonia (BOOP), acute interstitial pneumonia (AIP), desquamative interstitial pneumonia (DIP), respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), and lymphocytic interstitial pneumonia (LIP). In this review, our aim is to describe the pathogenic mechanisms that lead to the onset and progression of the different IIPs, starting from IPF as the most studied, in order to find both the common and standalone molecular and cellular key players among them. Finally, a deeper molecular and cellular characterization of different interstitial lung diseases without a known cause would contribute to giving a more accurate diagnosis to the patients, which would translate to a more effective treatment decision.

PMID:34445658 | DOI:10.3390/ijms22168952

Int J Mol Sci. 2021 Aug 9;22(16):8536. doi: 10.3390/ijms22168536.

ABSTRACT

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, and usually lethal lung disease and it has been widely accepted that fibroblast proliferation is one of the key characteristics of IPF. Long noncoding RNAs (lncRNAs) play vital roles in the pathogenesis of many diseases. In this study, we investigated the role of lncRNA FENDRR on fibroblast proliferation. Human lung fibroblasts stably overexpressing FENDRR showed a reduced cell proliferation compared to those expressing the control vector. On the other hand, FENDRR silencing increased fibroblast proliferation. FENDRR bound serine-arginine rich splicing factor 9 (SRSF9) and inhibited the phosphorylation of p70 ribosomal S6 kinase 1 (PS6K), a downstream protein of the mammalian target of rapamycin (mTOR) signaling. Silencing SRSF9 reduced fibroblast proliferation. FENDRR reduced β-catenin protein, but not mRNA levels. The reduction of β-catenin protein levels in lung fibroblasts by gene silencing or chemical inhibitor decreased fibroblast proliferation. Adenovirus-mediated FENDRR transfer to the lungs of mice reduced asbestos-induced fibrotic lesions and collagen deposition. RNA sequencing of lung tissues identified 7 cell proliferation-related genes that were up-regulated by asbestos but reversed by FENDRR. In conclusion, FENDRR inhibits fibroblast proliferation and functions as an anti-fibrotic lncRNA.

PMID:34445242 | DOI:10.3390/ijms22168536

Int J Mol Sci. 2021 Aug 5;22(16):8406. doi: 10.3390/ijms22168406.

ABSTRACT

Nuclear factor erythroid 2-related factor (Nrf2) is a transcriptional activator of the cell protection gene that binds to the antioxidant response element (ARE). Therefore, Nrf2 protects cells and tissues from oxidative stress. Normally, Kelch-like ECH-associated protein 1 (Keap1) inhibits the activation of Nrf2 by binding to Nrf2 and contributes to Nrf2 break down by ubiquitin proteasomes. In moderate oxidative stress, Keap1 is inhibited, allowing Nrf2 to be translocated to the nucleus, which acts as an antioxidant. However, under unusually severe oxidative stress, the Keap1-Nrf2 mechanism becomes disrupted and results in cell and tissue damage. Oxide-containing atmospheric environment generally contributes to the development of respiratory diseases, possibly leading to the failure of the Keap1-Nrf2 pathway. Until now, several studies have identified changes in Keap1-Nrf2 signaling in models of respiratory diseases, such as acute respiratory distress syndrome (ARDS)/acute lung injury (ALI), chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF), and asthma. These studies have confirmed that several Nrf2 activators can alleviate symptoms of respiratory diseases. Thus, this review describes how the expression of Keap1-Nrf2 functions in different respiratory diseases and explains the protective effects of reversing this expression.

PMID:34445113 | DOI:10.3390/ijms22168406

Int J Mol Sci. 2021 Aug 4;22(16):8388. doi: 10.3390/ijms22168388.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a refractory interstitial lung disease for which there is no effective treatment. Although the pathogenesis of IPF is not fully understood, TGF-β and epithelial-mesenchymal transition (EMT) have been shown to be involved in the fibrotic changes of lung tissues. Kurarinone is a prenylated flavonoid isolated from Sophora Flavescens with antioxidant and anti-inflammatory properties. In this study, we investigated the effect of kurarinone on pulmonary fibrosis. Kurarinone suppressed the TGF-β-induced EMT of lung epithelial cells. To assess the therapeutic effects of kurarinone in bleomycin (BLM)-induced pulmonary fibrosis, mice were treated with kurarinone daily for 2 weeks starting 7 days after BLM instillation. Oral administration of kurarinone attenuated the fibrotic changes of lung tissues, including accumulation of collagen and improved mechanical pulmonary functions. Mechanistically, kurarinone suppressed phosphorylation of Smad2/3 and AKT induced by TGF-β1 in lung epithelial cells, as well as in lung tissues treated with BLM. Taken together, these results suggest that kurarinone has a therapeutic effect on pulmonary fibrosis via suppressing TGF-β signaling pathways and may be a novel drug candidate for pulmonary fibrosis.

PMID:34445094 | DOI:10.3390/ijms22168388

J Clin Med. 2021 Aug 6;10(16):3474. doi: 10.3390/jcm10163474.

ABSTRACT

(1) Background: To assess sex differences in the incidence, characteristics, procedures and outcomes of patients admitted with idiopathic pulmonary fibrosis (IPF); and to analyze variables associated with in-hospital mortality (IHM). (2) Methods: We analyzed data collected by the Spanish National Hospital Discharge Database, 2016-2019. (3) Results: We identified 13,278 hospital discharges (66.4% men) of IPF (primary diagnosis 32.33%; secondary diagnosis: 67.67%). Regardless of the diagnosis position, IPF incidence was higher among men than women, increasing with age. Men had 2.74 times higher IPF incidence than women. Comorbidity was higher for men in either primary or secondary diagnosis. After matching, men had higher prevalence of pulmonary embolism and pneumonia, and women of congestive heart failure, dementia, rheumatoid disease and pulmonary hypertension. Invasive ventilation, bronchoscopy and lung transplantation were received more often by men than women. IHM was higher among men with IPF as primary diagnosis than among women and increased with age in both sexes and among those who suffered cancer, pneumonia or required mechanical ventilation. (4) Conclusions: Incidence of IPF was higher among men than women, as well as comorbidity and use of bronchoscopy, ventilation and lung transplantation. IHM was worse among men than women with IPF as primary diagnosis, increasing with age, cancer, pneumonia or mechanical ventilation use.

PMID:34441772 | DOI:10.3390/jcm10163474

Diagnostics (Basel). 2021 Jul 28;11(8):1359. doi: 10.3390/diagnostics11081359.

ABSTRACT

OBJECTIVES: to evaluate the number of cases of idiopathic pulmonary fibrosis (IPF) that included histological features of connective tissue disease (CTD) and to check whether they demonstrated the clinical features of CTD, using a previously reported CTD-interstitial pneumonia (IP) index that histologically differentiates CTD-associated and idiopathic IP.

METHODS: patients diagnosed with IPF following video-assisted thoracoscopic biopsy through multidisciplinary team diagnosis between 2014 and 2017 were selected. Pathological observation was made by four pathologists who scored eight observational items needed for the CTD-IP index. Cases determined as CTD, by the CTD-IP index, were extracted, and their clinical features were compared.

RESULTS: a total of 94 cases of IPF were identified, of which 20 were classified into the CTD group using the CTD-IP index with reasonable interobserver agreement (k = 0.76). Cases pathologically classified into the CTD group were significantly associated with female sex, non-smoking history, autoantibody positivity, and CTD symptoms (p = 0.01, 0.03, 0.01, and 0.04, respectively).

CONCLUSIONS: patients with IPF with pathological findings of CTD showed clinical characteristics similar to those of patients with CTD.

PMID:34441294 | DOI:10.3390/diagnostics11081359

Biomedicines. 2021 Aug 20;9(8):1058. doi: 10.3390/biomedicines9081058.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible, and highly fatal disease. It is characterized by the increased activation of both fibroblast and myofibroblast that results in excessive extracellular matrix (ECM) deposition. Extracellular vesicles (EVs) have been described as key mediators of intercellular communication in various pathologies. However, the role of EVs in the development of IPF remains poorly understood. This study aimed to characterize the differentially expressed proteins contained within EVs cargo derived from the fibroblast cell lines LL97A (IPF-1) and LL29 (IPF-2) isolated from lungs bearing IPF as compared to those derived from the fibroblast cell lines CCD8Lu (NL-1) and CCD19Lu (NL-2) isolated from healthy donors. Isolated EVs were subjected to label-free quantitative proteomic analysis by LC-MS/MS, and as a result, 331 proteins were identified. Differentially expressed proteins were obtained after the pairwise comparison, including all experimental groups. A total of 86 differentially expressed proteins were identified in either one or more comparison groups. Of note, proteins involved in fibrogenic processes, such as tenascin-c (TNC), insulin-like-growth-factor-binding protein 7 (IGFBP7), fibrillin-1 (FBN1), alpha-2 collagen chain (I) (COL1A2), alpha-1 collagen chain (I) (COL1A1), and lysyl oxidase homolog 1 (LOXL1), were identified in EVs cargo isolated from IPF cell lines. Additionally, KEGG pathway enrichment analysis revealed that differentially expressed proteins participate in focal adhesion, PI3K-Akt, and ECM-receptor interaction signaling pathways. In conclusion, our findings reveal that proteins contained within EVs cargo might play key roles during IPF pathogenesis.

PMID:34440261 | DOI:10.3390/biomedicines9081058

Biomolecules. 2021 Jul 22;11(8):1084. doi: 10.3390/biom11081084.

ABSTRACT

Periostin is known to be a useful biomarker for various diseases. In this article, we focus on allergic diseases and pulmonary fibrosis, for which we and others are now developing detection systems for periostin as a biomarker. Biomarker-based precision medicine in the management of type 2 inflammation and fibrotic diseases since heterogeneity is of utmost importance. Periostin expression is induced by type 2 cytokines (interleukin-4/-13) or transforming growth factor-β, and plays a vital role in the pathogenesis of allergic inflammation or interstitial lung disease, respectively, andits serum levels are correlated disease severity, prognosis and responsiveness to the treatment. We first summarise the importance of type 2 biomarker and then describe the pathological role of periostin in the development and progression of type 2 allergic inflammation and pulmonary fibrosis. In addition, then, we summarise the recent development of assay methods for periostin detection, and analyse the diseases in which periostin concentration is elevated in serum and local biological fluids and its usefulness as a biomarker. Furthermore, we describe recent findings of periostin as a biomarker in the use of biologics or anti-fibrotic therapy. Finally, we describe the factors that influence the change in periostin concentration under the healthy conditions.

PMID:34439751 | DOI:10.3390/biom11081084

Cancers (Basel). 2021 Aug 6;13(16):3979. doi: 10.3390/cancers13163979.

ABSTRACT

Of patients with advanced non-small-cell lung cancer (NSCLC), 5-10% have interstitial pneumonia (IP) at the time of diagnosis. To avoid fatal acute exacerbations of pre-existing IP, appropriate patient selection and low-risk treatment choices are warranted. Risk factors for acute exacerbation of pre-existing IP with cytotoxic drugs include honeycomb lungs on computed tomography (CT) and low forced vital capacity, but risk factors with immune checkpoint inhibitors (ICIs) have not been fully investigated. For advanced or recurrent NSCLC with comorbid IP, carboplatin plus nanoparticle albumin-bound paclitaxel is the standard of care for first-line treatment, but second-line or later treatment has not been established. ICI holds great promise for long-term survival, but many challenges remain, including safety and appropriate patient selection. Since the indications for pharmacotherapy and radiotherapy for NSCLC with comorbid IP are quite limited, surgical resection should be considered as much as possible for patients with operable stages. A scoring system has been reported to predict the risk of postoperative acute exacerbation of pre-existing IP, but perioperative treatment has not been established. In the future, it is necessary to accumulate more cases and conduct further research, not only in Japan but also worldwide.

PMID:34439135 | DOI:10.3390/cancers13163979

R I Med J (2013). 2021 Sep 1;104(7):26-29.

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is the most common of the idiopathic interstitial pneumonias. Its signs and symptoms are relatively non-specific, and patients often present with chronic cough, progressive dyspnea, resting or exertional hypoxemia, and inspiratory crackles on lung auscultation. Definitive diagnosis requires the exclusion of known causes of pulmonary fibrosis and identification of the usual interstitial pneumonia (UIP) pattern of disease either on high-resolution computed tomography (HRCT) scan of the chest or on surgical lung biopsy. Multidisciplinary discussion involving pulmonologists, radiologists, and pathologists with expertise in the diagnosis of IPF and other forms of interstitial lung disease is recommended and often required. Management focuses on anti-fibrotic therapy and early referral to lung transplant centers for those who are candidates. This review will discuss the current recommendations for the diagnosis, prognostication, and management of patients with IPF.

PMID:34437662

Int Immunopharmacol. 2021 Aug 17;99:108075. doi: 10.1016/j.intimp.2021.108075. Online ahead of print.

ABSTRACT

Idiopathic pulmonary fibrosis (PF) is a type of chronic lung disease. Here, we investigated the effect of induced pluripotent stem cell (iPSC)-derived exosomes (iPSC-exosomes) on M2-type macrophages which play a critical role in pulmonary fibrosis. Exosomes were purified from the conditioned medium of iPSCs. Mice models of pulmonary fibrosis were established by intratracheal instillation with 5 mg/kg bleomycin. Thereafter, the histopathological changes and collagen deposition were detected by HE and masson staining. Meanwhile the level of M2-type macrophages was elevated by immunofluorescence staining with F4/80 and Arg-1. Luciferase reporter assay was conducted to verify the binding of miR-302a-3p to ten-eleven translocation 1 (TET1). Our results showed that, after treatment with iPSC-exosomes, the pulmonary fibrosis induced by bleomycin was relieved, with less collagen deposition. In addition, the increased M2-type macrophages in PF mice were reduced upon treatment with iPSC-exosomes. Moreover, we found that the iPSC-exosomes showed higher level of miR-302a-3p. Interestingly, the level of miR-302a-3p in the lungs of PF mice was increased upon treatment with iPSC-exosomes. Furthermore, we verified that TET1 was a direct target of miR-302a-3p. Up-regulation of miR-302a-3p or TET1 silencing repressed M2-type macrophages. Down-regulation of miR-302a-3p abolished the beneficial effects of iPSC-exosomes on pulmonary fibrosis. Collectively, our study revealed that iPSC-exosomes delivered miR-302a-3p to suppress the M2-type macrophages via targeting TET1, thus mitigating pulmonary fibrosis. This study indicates that iPSC-exosomes may become a potential therapeutic agent for pulmonary fibrosis.

PMID:34435585 | DOI:10.1016/j.intimp.2021.108075

Matrix Biol Plus. 2021 Apr 20;11:100062. doi: 10.1016/j.mbplus.2021.100062. eCollection 2021 Aug.

ABSTRACT

The correct balance between collagen synthesis and degradation is essential for almost every aspect of life, from development to healthy aging, reproduction and wound healing. When this balance is compromised by external or internal stress signals, it very often leads to disease as is the case in fibrotic conditions. Fibrosis occurs in the context of defective tissue repair and is characterized by the excessive, aberrant and debilitating deposition of fibril-forming collagens. Therefore, the numerous proteins involved in the biosynthesis of fibrillar collagens represent a potential and still underexploited source of therapeutic targets to prevent fibrosis. One such target is procollagen C-proteinase enhancer-1 (PCPE-1) which has the unique ability to accelerate procollagen maturation by BMP-1/tolloid-like proteinases (BTPs) and contributes to trigger collagen fibrillogenesis, without interfering with other BTP functions or the activities of other extracellular metalloproteinases. This role is achieved through a fine-tuned mechanism of action that is close to being elucidated and offers promising perspectives for drug design. Finally, the in vivo data accumulated in recent years also confirm that PCPE-1 overexpression is a general feature and early marker of fibrosis. In this review, we describe the results which presently support the driving role of PCPE-1 in fibrosis and discuss the questions that remain to be solved to validate its use as a biomarker or therapeutic target.

PMID:34435180 | PMC:PMC8377038 | DOI:10.1016/j.mbplus.2021.100062