Progressive Pulmonary Disease Research Articles

Mechanisms of Lung Endothelial Cell Injury and Survival in Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is a progressive, chronic, and incurable inflammatory pulmonary vascular disease characterized by significant sex bias and largely unexplored microbial-associated molecular mechanisms that may influence its development and sex prevalence across various subgroups. PAH can be subclassified as idiopathic, heritable, or associated with conditions such as connective tissue diseases, congenital heart defects, liver disease, infections, and chronic exposure to drugs or toxins. During PAH progression, lung vascular endothelial cells (ECs) undergo dramatic morphofunctional transformations in response to acute and chronic inflammation. These transformations include the appearance and expansion of abnormal vascular cell phenotypes such as those derived from apoptosis-resistant cell growth and endothelial-to-mesenchymal transition (EndoMT). Compelling evidence indicates that these endothelial phenotypes seem to be triggered by chronic lung vascular injury and dysfunction, often characterized by reduced secretion of vasoactive molecules like nitric oxide (NO) and exacerbated response to vasoconstrictors such as Endothelin-1 (ET-1); both long-term known contributors of PAH pathogenesis. This review sheds light on the mechanisms of EC dysfunction, apoptosis, and EndoMT in PAH, aiming to unravel the intricate interactions between ECs, pathogens, and other cell types that drive the onset and progression of this devastating disease. Ultimately, we hope to provide an overview of the complex functions of lung vascular ECs in PAH, inspiring novel therapeutic strategies that target these dysfunctional cells to improve the treatment landscape for PAH, particularly in the face of current and emerging global pathogenic threats.

Pulmonary fibrosis insights and therapy targets from disease models and administration of the lipophilic diterpene, sodium tanshinone IIA sulfonate: Review and meta-analysis.

Pulmonary fibrosis (PF) is a chronic and progressive pulmonary interstitial disease of unknown etiology and is also a sequela in severe patients with the Coronavirus Disease 2019 (COVID-19). Seven databases were systematically searched to evaluate the preclinical evidence of Tanshinone IIA (Tan IIA) on PF. The quality of the included studies was assessed using a 10-item risk of bias tool, and data were analyzed using RevMan 5.3 software. 22 experiments from 12 studies on a total of 248 animals were included. The results showed that PF phenotype, such as fibrotic score, collagen I (Col-I), collagen III (Col-III), hydroxyproline (Hyp), in the group treated with Tan IIA were significantly lower than those in the model group (p<0.00001). The potential mechanisms of Tan IIA improvement of PF involve reducing inflammation, antioxidation, and suppressing activation of transforming growth factor beta 1 (TGF-β1). The subgroup analysis of different models, different rat species, and different dosage time showed significant reduction in fibrotic scores and Hyp levels with Tan IIA. The preclinical evidence indicated that Tan IIA might be a potent and promising agent for PF, but this conclusion should be further confirmed with more research.

Design, synthesis, and evaluation of a novel TRAIL-activated HDAC6 inhibitor for the treatment of pulmonary fibrosis

Pulmonary fibrosis (PF) is a common, severe, chronic, and progressive pulmonary interstitial disease characterized by rapid disease progression and high mortality. Despite the Food and Drug Administration (FDA)’s approval of two antifibrotic drugs, nintedanib and pirfenidone, effectively halting the progression of pulmonary fibrosis remains challenging. Histone deacetylase (HDAC) inhibitors have indeed emerged as an important class of antitumour drugs. However, their application in the treatment of fibrotic diseases is still relatively limited. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) has the potential to inhibit fibrotic processes by inducing fibroblast apoptosis. In this study, we designed and synthesized a series of histone deacetylase 6 (HDAC6) inhibitors that activate TRAIL, among which compound 7e exhibited potent inhibitory activity against HDAC6, with an IC50 of 42.90 ± 4.96 nM and superior antiproliferative effects on fibroblasts. Therefore, we further investigated its anti-pulmonary fibrosis effect in mouse models of both idiopathic pulmonary fibrosis (IPF) and silicosis. Our results suggest that compound 7e is a promising candidate for the treatment of pulmonary fibrosis.

Anomalous Origin of the Right Pulmonary Artery from the Ascending Aorta in a 10-Day-Old Boy: A Case Report

Anomalous origin of the right pulmonary artery from the ascending aorta is a rare anomaly, comprising approximately 0.1% of all congenital heart diseases. Patients suffered congestive heart failure in infancy, and some patients will experience progressive pulmonary vascular disease without surgical repair. In patients of this disease, early surgical intervention is generally advised and has demonstrated a high level of safety and efficacy, yielding excellent outcomes. We report a unique case involving a 10-day-old boy, characterized by the rare anomalous origination of the right pulmonary artery from the ascending aorta. This case is further complicated by the presence of a patent ductus arteriosus (PDA) and a right descending aorta. The ligation of the PDA and reimplantation of the right pulmonary artery (RPA) were successfully performed. The patient exhibited a favorable recovery trajectory postoperatively.

Pulmonary fibroblast-specific delivery of siRNA exploiting exosomes-based nanoscaffolds for IPF treatment

Idiopathic pulmonary fibrosis (IPF) is a progressive pulmonary disease that leads to interstitial inflammation, lung damage, and eventually life-threatening complications. Among various pathologic factors, Smad4 is a pivotal molecule involved in the progression and exacerbation of IPF. It mediates nuclear transfer of Smad2/Smad3 complexes and initiates the transcription of fibrosis-promoting genes. Thus, the inhibition of Smad4 expression in pulmonary fibroblasts by small interfering RNAs (siRNAs) might be a promising therapeutic strategy for IPF. Herein, we engineered exosome membranes (EM) by cationic lipid (i.e., DOTAP) to load siRNAs against Smad4 (DOTAP/siSmad4@EM), and investigated their specific delivery to pulmonary fibroblasts for treating IPF in a mouse model via pulmonary administration. As reference nanoscaffolds, undecorated DOTAP/siSmad4 complexes (lipoplexes, consisting of cationic lipid DOTAP and siRNAs) and siSmad4-loaded lipid nanoparticles (DOTAP/siSmad4@lipo, consisting of lipoplexes fused with DPPCChol liposomes) were also prepared. The results showed that DOTAP/siSmad4@EM exhibited a higher cellular uptake and gene silencing efficacies in mouse pulmonary fibroblasts (viz., MLg2908) as compared to the two reference nanoscaffolds. Furthermore, the outcomes of the in vivo experiments illustrated that DOTAP/siSmad4@EM could significantly down-regulate the Smad4 expression with augmented anti-fibrosis efficiency. Additionally, the DOTAP/siSmad4@EM conferred excellent biocompatibility with low cytokine levels in bronchoalveolar lavage fluid and proinflammatory responses in the pulmonary area. Taken together, the outcomes of our investigation imply that specific inhibition of Smad4 expression in pulmonary fibroblasts by pulmonary administrated DOTAP/siSmad4@EM is a promising therapeutic strategy for IPF, which could safely and effectively deliver siRNA drugs to the targeted site of action.

Exploring the Role of Trial Occlusion Test in Patent Ductus Arteriosus (PDA) Closure: A Serial Case

Background: Patent ductus arteriosus occurs in around 1 in 2000 full-term live newborns, making up 10-15% of cases of congenital heart disease. Percutaneous device closure is largely regarded as the preferred therapy for people diagnosed with PDA. Nevertheless, the closure of the PDA with a device is still a difficult task in patients with severe PAH. The trial occlusion strategy is used to evaluate the response of patients with severe pulmonary hypertension after closing the defect by briefly blocking it. This test has the potential to serve as a reliable predictor of the future progression of pulmonary hypertension. Case Presentation: We provide a report on three instances that underwent percutaneous closure of patent ductus arteriosus (PDA) in the presence of pulmonary hypertension. A 24-year-old adult patient arrived at our hospital with symptoms of intermittent dyspnea, easy fatigability, and occasional non-productive cough. The examination detected a persistent murmur located at the upper left sternal boundary. The patient received a diagnosis of patent ductus aorta and pulmonary hypertension. Discussion: The condition was successfully treated with transcatheter closure, which included a trial occlusion test. In the second instance, a toddler aged 2 was diagnosed with patent ductus aorta and pulmonary hypertension. The procedure of percutaneous PDA closure was scheduled. Following the trial occlusion test using the device occluder, we observed an elevation in pulmonary pressure which persisted and led to a pulmonary crisis. Conclusion: The trial occlusion test aids in identifying individuals who are prone to experiencing long-term regression of pulmonary hypertension and those who may deteriorate due to progressive pulmonary vascular disease (PVD) and right heart failure, therefore determining their suitability for PDA closure.

Low circulating lysophosphatidylcholine and phosphatidylcholine are linked to pulmonary hypertension severity

Background: Pulmonary hypertension (PH) is a progressive pulmonary vascular disease. Given the mechanistic role of lipids in peripheral vascular diseases, we hypothesized that PH is also associated with pathologic circulating lipid metabolites. To test this, lipid metabolites of patients with PH were evaluated in association with clinical severity, including right ventricle systolic pressure (RVSP), pulmonary vascular resistance (PVR), right ventricular size and function, and plasma endothelin-1. Methods and Results: Participants were recruited as a part of a small site clinical trial (Clinicaltrials.gov, # NCT01586156). Comprehensive lipidomes were determined using unbiased nontargeted lipidomics (Metabolon Inc., Durham, NC) in 30 PH patients and 12 healthy controls. RVSP, right ventricular end diastolic (RVED) and end systolic (RVES) area were measured by echocardiogram and PVR was calculated. Plasma endothelin-1 was measured by Elisa. Nontargeted analysis detected 1099 lipid-related metabolites of which 83 and 60 metabolites were upregulated and downregulated in PH ( p&lt;0.05), respectively. Pathway enrichment analysis identified abnormalities of lipid metabolic pathways including choline-related, acylcarnitine, and sphingolipid metabolism. Targeted measures of lysophosphatidylcholine (lysoPC) and phosphatidylcholine (PC) confirmed these findings. Total circulating lysoPC and PC were downregulated [Healthy vs. PH, mean ± SD, mM; LysoPC, 786±102 vs. 586±139, p&lt;0.01; PC, 1855±389 vs. 1495±282, p&lt;0.01]. Sixteen out of the 25 lysoPC detected, and 25 out of 39 PC detected, were lower in PH, including the most abundant lysoPC-16:0 [226±31 vs. 186±39, p&lt;0.01] and PC-34:2 [436±91 vs. 360±75, p&lt;0.01]. RVSP, PVR, RVED area, RVES area and endothelin-1 were all higher in PH (all, p&lt;0.01). Lipid metabolites were inversely related to clinical measures of PH severity. For example, lysoPC-20:3 was related to RVSP [ r=−0.63, p&lt;0.01], PVR [ r=−0.50, p&lt;0.01], and endothelin-1 [ r=−0.51, p&lt;0.01], and PC-36:5 was inversely related to RVSP [ r=−0.36, p=0.02], PVR [ r=−0.43, p&lt;0.01], and endothelin-1 [ r=−0.50, p&lt;0.01]. Additionally, both lysoPC-20:3 and PC36:5 metabolites were inversely associated with right ventricular size, measured as RVED area [lysoPC-20:3, r=−0.62, p&lt;0.01; PC-36:5, r=−0.69, p&lt;0.01], RVES area [lysoPC-20:3, r=−0.66, p&lt;0.01; PC-36:5, r=−0.71, p&lt;0.01] and related with RV systolic function, measured as RV fractional area change [lysoPC-20:3, r=0.57, p&lt;0.01; PC-36:5, r=0.50, p&lt;0.01). Conclusion: Plasma phosphatidylcholine is low in PH and is associated with disease severity, suggesting disturbances in PC metabolism are important in pulmonary vascular disease. NIH NHLBI R37HL60917, R01HL115008 CTSA UL1TR000439; UL1TR002548. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Stacking learning based on micro-CT radiomics for outcome prediction in the early-stage of silica-induced pulmonary fibrosis model

Silicosis is a progressive pulmonary fibrosis disease caused by long-term inhalation of silica. The early diagnosis and timely implementation of intervention measures are crucial in preventing silicosis deterioration further. However, the lack of screening and diagnostic measures for early-stage silicosis remains a significant challenge. In this study, silicosis models of varying severity were established through a single exposure to silica with different doses (2.5mg/mice or 5mg/mice) and durations (4 weeks or 12 weeks). The diagnostic performance of computed tomography (CT) quantitative analysis was assessed using lung density biomarkers and the lung density distribution histogram, with a particular focus on non-aerated lung volume. Subsequently, we developed and evaluated a stacking learning model for early diagnosis of silicosis after extracting and selecting features from CT images. The CT quantitative analysis reveals that while the lung densitometric biomarkers and lung density distribution histogram, as traditional indicators, effectively differentiate severe fibrosis models, they are unable to distinguish early-stage silicosis. Furthermore, these findings remained consistent even when employing non-aerated areas, which is a more sensitive indicator. By establishing a radiomics stacking learning model based on non-aerated areas, we can achieve remarkable diagnostic performance to distinguish early-stage silicosis, which can provide a valuable tool for clinical assistant diagnosis. This study reveals the potential of using non-aerated lung areas as a region of interest in stacking learning for early diagnosis of silicosis, providing new insights into early detection of this disease.

SHIFTing goals in cystic fibrosis—managing extrapulmonary disease in the era of CFTR modulator therapy; Proceedings of the International Shaping Initiatives and Future Trends (SHIFT) Symposium

AbstractBackgroundCystic fibrosis (CF) is a life‐shortening multisystem genetic disease. Although progressive pulmonary disease is the predominant cause of morbidity and mortality, improvements in treatment for CF‐related lung disease, with associated increase in longevity, have increased the prevalence of extrapulmonary manifestations1.MethodsTo discuss these issues, a multidisciplinary meeting of international leaders and experts in the field was convened in November 2021 at the Shaping Initiatives and Future Trends Symposium with the goal of highlighting shifting management paradigms in CF. The main topics covered were: (1) nutrition and obesity, (2) exocrine pancreas, (3) CF‐related diabetes, (4) CF liver disease, (5) CF‐related bone disease, and (6) post‐lung transplant care. This document summarizes the proceedings, highlighting the key priorities and important research questions that were discussed.ResultsImproved life expectancy, the advent of cystic fibrosis transmembrane conductance regulator modulators, and the increasing appreciation of the heterogeneity or spectrum of disease are leading to a shift in management for patients with cystic fibrosis. Care should be individualized to ensure that increased longevity is accompanied by improved extra‐pulmonary care and reduced morbidity.

Pulmonary manifestations and prognosis of a cohort of patients with interstitial lung disease and positive to anti-Th/To autoantibodies

IntroductionTh/To autoantibody may be relevant in evaluating patients with interstitial lung disease (ILD) because the clinical diagnosis of systemic sclerosis (SSc) may not be evident. The study's objective was to describe manifestations and evolution of pulmonary function in a cohort of ILD patients positive for Th/To autoantibodies. MethodsILD patients positive for anti-Th/To autoantibody were enrolled in this protocol. Baseline clinical features were registered, and survival analysis was performed to identify risk factors associated with worse survival. ResultsFifty-two patients positive for anti-Th/To autoantibodies with ILD were included. Only 21% of the patients fulfilled the ACR/EULAR 2013 systemic sclerosis classification criteria, and 63.4% fulfilled the IPAF ATS/ERS 2015 criteria. Twenty-five percent of the patients died during follow-up. Respiratory failure was the principal cause of death. Twenty-nine patients (56%) were positive for other hallmark SSc autoantibodies. The most frequent HRCT pattern was nonspecific interstitial pneumonia (NISP). Survival was strongly associated to the systolic pulmonary arterial pressure (sPAP), male sex and the extent of fibrosis in HRCT; besides, patients positive for other hallmark SSc autoantibodies had worse survival compared to those positive only to anti-Th/To. Seventy-six percent of them behaved as fibrotic progressive pulmonary disease, with an absolute decline of the FVC of at least 5%. ConclusionsOnly a small proportion of ILD patients positive for Th/To meet the criteria to be classified as SSc; however, most met criteria for IPAF. A high proportion of patients behave as progressive fibrotic pulmonary disease. Survival is associated with sPAP, the extent of lung disease, and the presence of other hallmark SSc autoantibodies.

Role and targeting of the AGC kinase family in pulmonary fibrosis (Review).

Pulmonary fibrosis (PF) is a progressive and irreversible pulmonary disease with a high mortality rate and limited treatment options. The cAMP-dependent protein kinase A, cGMP-dependent protein kinase G and phospholipid-dependent protein kinase C, collectively known as AGC kinases, are evolutionarily conserved protein kinases that are widely distributed among eukaryotes. AGC kinases serve a crucial role in a variety of cellular functions and pathological processes, including cancer, diabetes, inflammation and viral infections, where they have been implicated the pathogenesis of PF. The present review summarizes the evidence for the involvement of specific AGC kinases in the pathogenesis of PF, and provides a theoretical basis for the development of targeted AGC kinase small molecule inhibitors or targeted drugs, offering more effective treatment options and strategies for patients with PF.

Multiple genetic loci influence vaccine-induced protection against Mycobacterium tuberculosis in genetically diverse mice.

Mycobacterium tuberculosis (M.tb.) infection leads to over 1.5 million deaths annually, despite widespread vaccination with BCG at birth. Causes for the ongoing tuberculosis endemic are complex and include the failure of BCG to protect many against progressive pulmonary disease. Host genetics is one of the known factors implicated in susceptibility to primary tuberculosis, but less is known about the role that host genetics plays in controlling host responses to vaccination against M.tb. Here, we addressed this gap by utilizing Diversity Outbred (DO) mice as a small animal model to query genetic drivers of vaccine-induced protection against M.tb. DO mice are a highly genetically and phenotypically diverse outbred population that is well suited for fine genetic mapping. Similar to outcomes in people, our previous studies demonstrated that DO mice have a wide range of disease outcomes following BCG vaccination and M.tb. challenge. In the current study, we used a large population of BCG-vaccinated/M.tb.-challenged mice to perform quantitative trait loci mapping of complex infection traits; these included lung and spleen M.tb. burdens, as well as lung cytokines measured at necropsy. We found sixteen chromosomal loci associated with complex infection traits and cytokine production. QTL associated with bacterial burdens included a region encoding major histocompatibility antigens that are known to affect susceptibility to tuberculosis, supporting validity of the approach. Most of the other QTL represent novel associations with immune responses to M.tb. and novel pathways of cytokine regulation. Most importantly, we discovered that protection induced by BCG is a multigenic trait, in which genetic loci harboring functionally-distinct candidate genes influence different aspects of immune responses that are crucial collectively for successful protection. These data provide exciting new avenues to explore and exploit in developing new vaccines against M.tb.

Oral Prostacyclin Pathway Agents Used in PAH: A Targeted Literature Review.

Pulmonary arterial hypertension (PAH) is a rare and progressive pulmonary vascular disease that can result in right heart failure and death. Oral prostacyclins play an important role in the management of intermediate-low risk PAH. This targeted literature review (TLR) aimed to identify and compare evidence supporting use of oral prostacyclin pathway agents (PPAs: selexipag and oral treprostinil) in intermediate-low risk PAH. A targeted literature review was conducted. Literature databases (MEDLINE, Embase, and Cochrane reviews) were searched for studies describing clinical practice and treatment outcomes for oral treprostinil and selexipag globally, published in English (2012 to 2022). Electronic searches were supplemented by manual-searches of targeted conferences (2020 to 2022), and reference lists of identified publications were reviewed. One reviewer assessed studies for eligibility. In total, 95 publications met inclusion criteria: 47 full-text articles (selexipag n = 22; oral treprostinil n = 16; selexipag and oral treprostinil n = 9) and 48 conference materials. Selexipag and oral treprostinil target the prostacyclin pathway differently; their label-supporting trials had different primary endpoints (disease progression and hospitalization vs exercise capacity and disease progression), differing baseline therapy (0, 1 or 2 vs 0 or 1 baseline treatments), titration duration and dosing (personalized dose capped at 1600 ug twice daily (BID) vs increasing doses over time with no maximum dose), respectively. While both oral PPAs have demonstrated reduced risk of disease progression, only selexipag showed reduction in hospitalization rates. Oral PPAs have been shown to reduce healthcare costs in real-world clinical practice. This difference is reflected in labeled indications. Given differences in trial- and real-world outcomes, number of prior therapies, and dosing, personalizing the choice of oral PPA is critical to maximizing the benefit for individual patients.

The Correlation between Lung Ultrasound and Pathology in Rat Model of Monocrotaline-Induced Pulmonary Hypertension.

Pulmonary hypertension (PH) is a progressive and complex pulmonary vascular disease with poor prognosis. The aim of this study was to provide a new understanding of the lung pathology of disease and a noninvasive method in monitoring the establishment of animal models for basic and clinical studies of PH, indeed to explore clinical application value of lung ultrasound for patients with PH. Totally 32 male SD rats were randomly divided into control group, MCT (monocrotaline) group, PDTC (pyrrolidine dithiocarbamate) group, and NS (normal saline) group. Rats in the MCT group, PDTC group, and NS group received single intraperitoneal injection of MCT, while the control group received the same dose of NS. Then, PDTC group and NS group received PDTC and NS daily for treatment at the end of the model. Each group received lung ultrasound examination and measurement of pulmonary arterial pressure (PAP). Then, the rats were sacrificed to take the lung specimens to being observed. The ultrasound and pathological results were analyzed with a semiquantitative score. With the pulmonary artery pressure increases, the MCT group had a higher pulmonary ultrasound score and pathological score compared with the control group (p < 0.05). After PDTC treatment, the pulmonary ultrasound score and the pathological score decline (p < 0.05). We investigated both lung ultrasound scores, and the pathological scores were positively correlated with mean pulmonary artery pressure (mPAP) (both r > 0.8, p < 0.0001). Moreover, lung ultrasound scores were positively correlated with pathological scores (r > 0.8, p < 0.0001). We elucidated lung ultrasound evaluation providing more evidence for the management of PH in the rat model. Moreover, lung ultrasound provided a noninvasive method in monitoring the establishment of animal models for basic and clinical studies of PH.

USP7 Promotes TGF-β1 Signaling by De-Ubiquitinating Smad2/Smad3 in Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a long-term, progressive, and irreversible pulmonary interstitial disease. The activation of Smad family member 2 (Smad2) and Smad3 transcription factors by transforming growth factor β-1 (TGF-β1) is a critical event in the pathogenesis of IPF. However, there is still a lack of understanding regarding the molecular mechanisms governing Smad2 and Smad3 proteins. Ubiquitin-specific protease 7 (USP7) is a deubiquitinase that plays a vital role in regulating protein stability within cells. However, its regulation of the TGF-β signaling pathway and its significance in IPF remain undiscovered. This study aims to clarify the function of USP7 in the TGF-β signaling pathway, while simultaneously exploring the specific molecular mechanisms involved. Additionally, this study seeks to evaluate the therapeutic potential of targeted USP7 inhibitors in IPF, thereby providing novel insights for the diagnosis and management of IPF. We first detected the expression of USP7 in lung tissues of mice with Bleomycin (BLM)-induced pulmonary fibrosis and in Beas-2B cells treated with or without TGF-β1 through Western blot analysis. Subsequently, we explored the influence of USP7 on fibrotic processes and the TGF-β1 signaling pathway, utilizing in vitro and in vivo studies. Finally, we assessed the effectiveness of USP7-specific inhibitors in an IPF murine model. In the present study, USP7 was found to de-ubiquitinate Smad2 and Smad3, consequently increasing their stability and promoting the TGF-β1-induced production of profibrotic proteins including α-smooth muscle actin (α-SMA) and fibronectin 1 (FN-1). Inhibition or knockdown of USP7 resulted in decreased levels of Smad2 and Smad3 proteins, leading to reduced expression of FN-1, Collagen Type I Alpha 1 Chain (Col1A1), and α-SMA induced by TGF-β1 in human pulmonary epithelial cells. These findings demonstrate that overexpression of USP7 reduces Smad2/3 ubiquitination, whereas inhibition or knockdown of USP7 enhances their ubiquitination. USP7 is abundantly expressed in IPF lungs. The expressions of USP7, Smad2, and Smad3 were upregulated in bleomycin-induced lung injury. The USP7 inhibitor P22077 reduced the expression of FN-1 and type I collagen as well as Smad2/3 and collagen deposition in lung tissue in a model of pulmonary fibrosis induced by bleomycin. This study demonstrates that USP7 promotes TGF-β1 signaling by stabilizing Smad2 and Smad3. The contribution of USP7 to the progression of IPF indicates it may be a viable treatment target.

Lung Organoid on a Chip: A New Ensemble Model for Preclinical Studies.

The lung is a complex organ comprising a branched airway that connects the large airway and millions of terminal gas-exchange units. Traditional pulmonary biomedical research by using cell line model system have limitations such as lack of cellular heterogeneity, animal models also have limitations including ethical concern, race-to-race variations, and physiological differences found in vivo. Organoids and on-a-chip models offer viable solutions for these issues. Organoids are three-dimensional, self-organized construct composed of numerous cells derived from stem cells cultured with growth factors required for the maintenance of stem cells. On-a-chip models are biomimetic microsystems which are able to customize to use microfluidic systems to simulate blood flow in blood channels or vacuum to simulate human breathing. This review summarizes the key components and previous biomedical studies conducted on lung organoids and lung-on-a-chip models, and introduces potential future applications. Considering the importance and benefits of these model systems, we believe that the system will offer better platform to biomedical researchers on pulmonary diseases, such as emerging viral infection, progressive fibrotic pulmonary diseases, or primary or metastatic lung cancer.

Pulmonary sarcoidosis: A comprehensive review: Past to present

Sarcoidosis is a sterile non-necrotizing granulomatous disease without known causes that can involve multiple organs with a predilection for the lung and thoracic lymph nodes. Worldwide it is estimated to affect 2–160/100,000 people and has a mortality rate over 5 years of approximately 7%. For sarcoidosis patients, the cause of death is due to sarcoid in 60% of the cases, of which up to 80% are from advanced cardiopulmonary failure (pulmonary hypertension and respiratory microbial infections) in all races except in Japan were greater than 70% of the sarcoidosis deaths are due to cardiac sarcoidosis.Scadding stages for pulmonary sarcoidosis associates with clinical outcomes. Stages I and II have radiographic remission in approximately 30%–80% of cases. Stage III only has a 10%–40% chance of resolution, while stage IV has no change of resolution. Up to 40% of pulmonary sarcoidosis patients progress to stage IV disease with lung parenchyma fibroplasia, bronchiectasis with hilar retraction and fibrocystic disease. These patients are at highest risk for the development of precapillary pulmonary hypertension, which may occur in up to 70% of these patients. Sarcoid patients with pre-capillary pulmonary hypertension can respond to targeted pulmonary arterial hypertension medications. Stage IV fibrocytic sarcoidosis with significant pulmonary physiologic impairment, >20% fibrosis on HRCT or pre-capillary pulmonary hypertension have the highest risk of mortality, which can be >40% at 5-years.First line treatment for patients who are symptomatic (cough and dyspnea) with parenchymal infiltrates and abnormal pulmonary function testing (PFT) is oral glucocorticoids, such as prednisone with a typical starting dose of 20–40 mg daily for 2 weeks to 2 months. Prednisone can be tapered over 6–18 months if symptoms, spirometry, PFTs, and radiographs improve. Prolonged prednisone may be required to stabilize disease. Patients requiring prolonged prednisone ≥10 mg/day or those with adverse effects due to glucocorticoids may be prescribed second and third line treatements. Second and third line treatments include immunosuppressive agents (e.g., methotrexate and azathioprine) and anti-tumor necrosis factor (TNF) medication; respectively. Effective treatments for advanced fibrocystic pulmonary disease are being explored. Despite different treatments, relapse rates range from 13% to 75% depending on the stage of sarcoid, number of organs involved, socioeconomic status, and geography. ConclusionThe mortality rate for sarcoidosis over a 5 year follow up is approximately 7%. Unfortunately, 10%–40% of patients with sarcoidosis develop progressive pulmonary disease, and >60% of deaths resulting from sarcoidosis are due to advance cardiopulmonary disease. Oral glucocorticoids are the first line treatment, while methotrexate and azathioprine are considered second and anti-TNF agents are third line treatments that are used solely or as glucocorticoid sparing agents for symptomatic extrapulmonary or pulmonary sarcoidosis with infiltrates on chest radiographs and abnormal PFT. Relapse rates have ranged from 13% to 75% depending on the population studied.

OA19 A complex case of bilateral pneumothoraces due to probable certolizumab driven rheumatoid lung nodules

OA19 A complex case of bilateral pneumothoraces due to probable certolizumab driven rheumatoid lung nodules

Dexmedetomidine alleviates pulmonary fibrosis through the ADORA2B-Mediated MAPK signaling pathway

BackgroundIdiopathic pulmonary fibrosis (IPF) is a chronically progressive fibrotic pulmonary disease characterized by an uncertain etiology, a poor prognosis, and a paucity of efficacious treatment options. Dexmedetomidine (Dex), an anesthetic-sparing alpha-2 adrenoceptor (α2AR) agonist, plays a crucial role in organ injury and fibrosis. However, the underlying mechanisms of IPF remain unknown.MethodsIn our study, the role of Dex in murine pulmonary fibrosis models was determined by Dex injection intraperitoneally in vivo. Fibroblast activation and myofibroblast differentiation were assessed after Dex treatment in vitro. The activation of MAPK pathway and the expression of Adenosine A2B receptor (ADORA2B) were examined in lung myofibroblasts. Moreover, the role of ADORA2B in Dex suppressing myofibroblast differentiation and pulmonary fibrosis was determined using the ADORA2B agonist BAY60-6583.ResultsThe results revealed that Dex could inhibit Bleo-induced pulmonary fibrosis in mice. In vitro studies revealed that Dex suppressed TGF-β-mediated MAPK pathway activation and myofibroblast differentiation. Furthermore, Dex inhibits myofibroblast differentiation and pulmonary fibrosis via downregulating ADORA2B expression.ConclusionsOur findings suggest Dex as a potential therapeutic agent for pulmonary fibrosis. Dex may alleviate lung fibrosis and myofibroblast differentiation through the ADORA2B-mediated MAPK signaling pathway.

Grape Seed Proanthocyanidin Ameliorates LPS-induced Acute Lung Injury By Modulating M2a Macrophage Polarization Via the TREM2/PI3K/Akt Pathway

Acute lung injury (ALI) is an acute and progressive pulmonary inflammatory disease that is difficult to cure and has a poor prognosis. Macrophages, which have various phenotypes and diverse functions, play an essential role in the pathogenesis of ALI. Grape seed proanthocyanidin (GSP) has received much attention over several decades, and many biological activities such as anti-apoptotic, antioxidant, and anti-inflammatory have been identified. This study aimed to determine the effect of GSP on lipopolysaccharide (LPS)-induced ALI. In this study, we established an ALI mouse model by tracheal instillation of LPS, and by pre-injection of GSP into mice to examine the effect of GSP on the ALI mouse model. Using H&E staining, flow cytometry, and ELISA, we found that GSP attenuated LPS-induced lung pathological changes and decreased inflammatory cytokine expression in ALI mice. In addition, GSP reduced the recruitment of monocyte-derived macrophages to the lung and significantly promoted the polarization of primary mouse lung macrophages from M1 to M2a induced by LPS. In vitro, GSP also decreased the expression levels of inflammatory cytokines such as TNF-α, IL-6, IL-1β, and M1 macrophage marker iNOS induced by LPS in MH-S cells, while increasing the expression levels of M2a macrophage marker CD206. Bioinformatics analysis identified TREM2 and the PI3K/Akt pathway as candidate targets and signaling pathways that regulate M1/M2a macrophage polarization in ALI, respectively. Furthermore, GSP activated PI3K/Akt and increased TREM2 expression in vivo and in vitro. Meanwhile, GSP's impact on M2a polarization and inflammation suppression was attenuated by the PI3K inhibitor LY294002 or siRNA knockdown TREM2. In addition, GSP-enhanced PI3K/Akt activity was prevented by TREM2 siRNA. In conclusion, this study demonstrated that GSP could ameliorate LPS-induced ALI by modulating macrophage polarization from M1 to M2a via the TREM2/PI3K/Akt pathway.