Idiopathic pulmonary fibrosis

Single-cell transcriptome analysis revealing mechanotransduction via the Hippo/YAP pathway in promoting fibroblast-to-myofibroblast transition and idiopathic pulmonary fibrosis development

OBJECTIVE

Idiopathic pulmonary fibrosis (IPF) is an irreversible and fatal interstitial lung disease, characterized by excessive extracellular matrix (ECM) secretion that disrupts normal alveolar structure. This study aims to explore the potential molecular mechanisms underlying the promotion of IPF development.

METHODS

Firstly, we compared the transcriptome and single-cell sequencing data from lung tissue samples of patients with IPF and healthy individuals. Subsequently, we conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses on the differentially expressed genes (DEGs). Furthermore, we employed sodium alginate hydrogels with varying degrees of crosslinking to provide differential mechanical stress, mimicking the mechanical microenvironment in vivo during lung fibrosis. On this basis, we examined cytoskeletal remodeling in fibroblasts MRC-5, mRNA expression of multiple related genes, immunofluorescence localization, and cellular proliferation capacity.

RESULTS

Bioinformatics analysis revealed a series of DEGs associated with IPF. Further functional and pathway enrichment analyses indicated that these DEGs were primarily enriched in ECM-related biological processes. Single-cell sequencing data revealed that fibroblasts and myofibroblasts are the main contributors to excessive ECM secretion and suggested activation of mechanotransduction and the Hippo/YAP signaling pathway in myofibroblasts. Cellular experiments demonstrated that sodium alginate hydrogels with different stiffness can simulate different mechanical stress environments, thereby affecting cytoskeletal rearrangement and Hippo/YAP pathway activity in MRC-5 lung fibroblasts. Notably, high levels of mechanical stress promoted YAP nuclear translocation, increased expression of type I collagen and α-SMA, and enhanced proliferative capacity. Additionally, we also found that fibroblasts primarily participate in mechanotransduction through the Rho/ROCK and Integrin/FAK pathways under high mechanical stress conditions, ultimately upregulating the gene expression of CCNE1/2, CTGF, and FGF1.

CONCLUSION

Our study uncovers the crucial role of cytoskeletal mechanotransduction in myofibroblast transformation and IPF development through activation of the Hippo/YAP pathway, providing new insights into understanding the pathogenesis of IPF.

The dual missions of FoxO3a in inflammatory diseases: Regulation of antioxidant enzymes and involvement in programmed cell death

The transcription factor FoxO3a plays a crucial role in the process of cells adapting to various stress conditions. Multiple post - translational modifications and epigenetic mechanisms work together to precisely regulate the activity of FoxO3a, influencing its subcellular localization, stability, interactions with other proteins, DNA - binding affinity, and transcriptional regulatory capacity. Under different chemical signal stimuli and subcellular environments, the activation of FoxO3a triggered by oxidative stress can initiate diverse transcriptional programs, which are essential for the body to resist oxidative damage. In the development and progression of inflammatory diseases, FoxO3a exerts an important function by regulating the expression levels of antioxidant enzymes and participating in key physiological processes such as programmed cell death. This article comprehensively reviews the structural characteristics, mechanism of action of FoxO3a, as well as its functions in regulating antioxidant enzymes and programmed cell death. The aim is to deeply explore the potential of FoxO3a as a potential therapeutic target for preventing and treating damages such as inflammatory diseases caused by cellular stress.

Nintedanib improves bleomycin-induced pulmonary fibrosis by inhibiting the Clec7a/SPP1 pathway in interstitial macrophages

Idiopathic pulmonary fibrosis (IPF) is a terminal lung disease with high mortality rate. Although Nintedanib (Nin) is an effective treatment for IPF, its precise mechanism of action remains unclear. In this study, we performed an integrated analysis of single-cell sequencing and RNA-seq data from lung tissues of both fibrotic and Nin-treated fibrotic mice to uncover new therapeutic mechanisms of Nin in IPF. Our results revealed an increase in interstitial macrophages following bleomycin (BLM) treatment. We used Monocle2, Cellchat, and in vivo experiments to demonstrate that Nin can inhibit Clec7a in interstitial macrophages, thereby suppressing the SPP1-mediated profibrotic pathway. Additionally, we utilized Scenic to predict transcription factors and identified NFκB as a major transcription factor in interstitial macrophages. In the in vitro experiments, we found that inhibiting Clec7a improved the secretion of SPP1 by M2 macrophages through the NFκB pathway. In subsequent in vivo experiments, we found that inhibiting of Clec7a improves pulmonary fibrosis through the NFκB/SPP1 pathway, and Nin alleviated BLM-induced pulmonary fibrosis by inhibiting Clec7a in interstitial macrophages. In summary, our study indicates that interstitial macrophages are upregulated in pulmonary fibrosis, and Nin reduces fibrosis by inhibiting Clec7a in interstitial macrophages, which in turn diminishes the NFκB /SPP1 pathway. These findings provided a new perspective on the mechanism of action of Nin in treating pulmonary fibrosis.

Intranasal delivery of extracellular vesicles: A promising new approach for treating neurological and respiratory disorders

BACKGROUND

Extracellular vesicles (EVs) are membrane vesicles secreted by all types of cells, including bacteria, animals, and plants. These vesicles contain proteins, nucleic acids, and lipids from their parent cells and can transfer these components between cells. EVs have attracted attention for their potential use in diagnosis and therapy due to their natural properties, such as low immunogenicity, high biocompatibility, and ability to cross the blood-brain barrier. They can also be engineered to carry therapeutic molecules. EVs can be delivered via various routes. The intranasal route is particularly advantageous for delivering them to the central nervous system, making it a promising approach for treating neurological disorders.

SCOPE OF REVIEW

This review delves into the promising potential of intranasally administered EVs-based therapies for various medical conditions, with a particular focus on those affecting the brain and central nervous system. Additionally, the potential use of these therapies for pulmonary conditions, cancer, and allergies is examined, offering a hopeful outlook for the future of medical treatments.

MAJOR CONCLUSIONS

The intranasal administration of EVs offers significant advantages over other delivery methods. By directly delivering EVs to the brain, specifically targeting areas that have been injured, this administration proves to be highly efficient and effective, providing reassurance about the progress in medical treatments. Intranasal delivery is not limited to brain-related conditions. It can also benefit other organs like the lungs and stimulate a mucosal immune response against various pathogens due to the highly vascularized nature of the nasal cavity and airways. Moreover, it has the added benefit of minimizing toxicity to non-targeted organs and allows the EVs to remain longer in the body. As a result, there is a growing emphasis on conducting clinical trials for intranasal administration of EVs, particularly in treating respiratory tract pathologies such as coronavirus disease.

Design, synthesis, and biological evaluation of a potent and orally bioavailable FGFRs inhibitor for fibrotic treatment

Organ fibrosis, such as lung fibrosis and liver fibrosis, is a progressive and fatal disease. Fibroblast growth factor receptors (FGFRs) play an important role in the development and progression of fibrosis. Through scaffold hopping, bioisosteric replacement design, and structure-activity relationship optimization, we developed a series of highly potent FGFRs inhibitors, and the indazole-containing candidate compound A16 showed potent kinase activity comparable to that of AZD4547. In addition, A16 effectively suppressed the activation of lung fibroblasts and hepatic stellate cells (HSCs) induced by TGF-β1, leading to a reduction in collagen deposition. Notably, A16 exhibited potent anti-fibrotic effects through the inhibition of the FGFR pathway in vitro. Compound A16 also showed reasonable pharmacokinetic properties (F = 21.84 %) and favorable cardiac safety (hERG IC50 > 20 μM). Moreover, in models of pulmonary fibrosis, A16 ameliorated (in the prevention model) and reversed (in the treatment model) bleomycin-induced lung fibrosis, as well as mitigated inflammatory immune response in the lung. Furthermore, in the CCl4-induced liver fibrosis model, when A16 was administrated orally at a dose of 30 mg/kg/day for 3 weeks, it effectively improved liver function, restored damaged liver structures, and reduced collagen deposition. Taken together, these results suggest that A16 could be a potential drug candidate for the treatment of organ fibrosis.

Decreased Complex I Activity in Blood lymphocytes Correlates with Idiopathic Pulmonary Fibrosis Severity

Idiopathic pulmonary fibrosis (IPF) is a progressive interstitial lung disease linked to aging. Mitochondrial dysfunction in circulating T cells, often caused by disruption of mitochondrial DNA (mtDNA), may play a role in age-related conditions like IPF. In our previous study, we found high mtDNA mutational loads in blood lymphocytes from IPF patients, especially in regions critical for mtDNA expression. Since Complex I of the electron transport chain, partly encoded by mtDNA, is essential for energy production, we conducted a preliminary study on its activity. We found significantly reduced Complex I activity (p < 0.001) in lymphocytes from 40 IPF patients compared to 40 controls, which was positively correlated with lung function decline, specifically in functional vital capacity and diffusing capacity for carbon monoxide. These findings indicate that T cell mitochondrial dysfunction is associated with disease progression in IPF. Future work will explore the mechanisms linking T cell mitochondrial disruption with fibrosis, potentially uncovering new therapeutic targets.

Btbd8 deficiency exacerbates bleomycin-induced pulmonary fibrosis in mice by enhancing myofibroblast accumulation and inflammatory responses

BTBD8 contributes to the pathogenesis of inflammatory bowel disease through regulating intestinal barrier integrity and inflammation. However, its role in idiopathic pulmonary fibrosis (IPF) remains unknown. Here we investigated whether BTBD8 plays a role in bleomycin-induced pulmonary fibrosis. Pulmonary fibrosis was induced in wild-type (WT) and Btbd8 knockout (KO) mice by intratracheal instillation of bleomycin. The mice were sacrificed on day 7 or 12. Subsequently, the progression of bleomycin-induced pulmonary fibrosis was assessed. We found that Btbd8 KO mice are more susceptible to bleomycin-induced pulmonary fibrosis, with more severe body weight loss and pulmonary injury, increased collagen deposition and myofibroblast accumulation. We further demonstrated that BTBD8 functions in pulmonary fibroblasts to suppress the conversion of fibroblasts to myofibroblasts. Moreover, Btbd8 deficiency promotes the infiltration of inflammatory cells and the secretion of pro-inflammatory cytokines in IPF mouse model. These results highlight the critical role of BTBD8 in the pathogenesis of bleomycin-induced pulmonary fibrosis in mice, and suggest that BTBD8 may alleviate bleomycin-induced fibrosis by suppressing the differentiation of fibroblasts to myofibroblast, as well as inflammatory responses.

Effect of Alpinia officinarum Rhizome extract on experimentally induced lung fibrosis: The pertinent role of Sirt1 and Nrf2 antioxidant pathways

BACKGROUND

Pulmonary fibrosis (PF) is a frequently reported COVID-19 sequela. It is a progressive disorder characterized by respiratory failure and death. The properties of Alpinia officinarum Rhizomes (AO) make it a highly potent antioxidant, anti-inflammatory, and antifibrotic agent. This study has evaluated AO's protective effects on bleomycin-induced PF in rats and investigated the underlying mechanisms.

MATERIAL AND METHODS

Bleomycin (5mg/kg, intratracheally) was used to induce PF in albino rats, and then, AO extract (200mg/kg/daily, orally) was administrated for 28days post-bleomycin-instillation. After euthanizing the rats, the biochemical, quantitative real-time polymerase chain reaction (qPCR) and histopathological examination of lung tissue were determined.

RESULTS

Findings have revealed that bleomycin significantly increased the tissue level of malondialdehyde, tumor necrosis factor-alpha, and interleukin-6, Silent information regulator 1 (Sirt1), and nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA levels. Furthermore, the total antioxidant capacity level decreased in the lungs of bleomycin-instilled rats. However, AO extract significantly decreased histopathological injuries in hematoxylin & eosin, Masson's trichrome-stained sections, inducible nitric oxide synthase and α-smooth muscle actin, transforming growth factor beta 1 immunoexpression.

CONCLUSION

Alpinia officinarum Rhizomes extract appears to protect against bleomycin-induced PF, possibly due to its antioxidant, anti-inflammatory, and antifibrotic properties.

Structural optimization and biological evaluation of indolin-2-one derivatives as novel CDK8 inhibitors for idiopathic pulmonary fibrosis

Cyclin-dependent kinase 8 (CDK8) plays a crucial role in the transforming growth factor beta (TGF-β) signaling pathway, which is critical to the pathology of idiopathic pulmonary fibrosis (IPF). CDK8 promotes the epithelial-mesenchymal transition (EMT) and excessive extracellular matrix (ECM) deposition, making it a promising target for IPF treatment. This study focused on optimizing F059-1017, a previously identified CDK8 inhibitor, to enhance its potency. Through integrated structure-based modifications, a series of compounds was synthesized, and their inhibitory effects on CDK8 were tested. Results indicated that substituting with cyclopentanone significantly improved the inhibitory activity, and compound 4j demonstrated the best potency (IC50 = 16 nM). Notably, compared to F059-1017, its potency increased 35-fold, and kinase profiling revealed that the compound was selective for CDK8. Compound 4j inhibited the TGF-β1-induced EMT, cell migration, and morphological changes in A549 cells at a concentration of 0.1 μM and inhibited ECM and EMT protein expressions. In addition, the compound blocked TGF-β1-induced transcriptional changes and inhibited Smad3 and RNA polymerase II phosphorylation. These results highlight the potential of the optimized CDK8 inhibitor as a prospective drug for IPF treatment.

Specnuezhenide: Comprehensive review of pharmacology, pharmacokinetics and ethnomedicinal uses

BACKGROUND

Specnuezhenide (SPN) is a bioactive iridoid terpenoid compound mainly found in Ligustri Lucidi Fructus (LLF), that has a broad spectrum of pharmacological effects, including anti-neoplastic, hepatoprotective, anti-aging, anti-inflammatory, immune-modulatory properties.

PURPOSE

The present review provides a comprehensive summary of natural medicinal plants, traditional Chinese medicine compounds containing SPN, and their corresponding pharmacological mechanisms.

METHODS

Using several globally recognized databases such as Web of Science, Google Scholar, PubMed, ScienceDirect, Wiley, ACS, Springer, and CNKI until December 2024, A comprehensive literature search and analysis was carried out with the keywords "Specnuezhenide", " Pharmacology ", "Pharmacokinetics" and " Chinese herbal compound".

RESULTS

The results indicated that SPN is present in a diverse range of plants, including LLF, Osmanthus fragrans seeds and Naked barley. SPN plays an anti-inflammatory role by regulating the NF-κB and MAPK signaling pathways, down-regulating the expression of TNF-α, IL-1β, IL-6 and other cytokines. Furthermore, many Chinese herbal compounds have been found to contain SPN, such as treatment of spleen and kidney deficiency of compound Shenhua tablet, treatment of liver-kidney Yin deficiency of Er Zhi Wan, treatment of pulmonray abscess of Qidongning and treatment of stagnation of QI due to depression of the liver of Shuganzhi Tablet. SPN is primarily distributed in the stomach, intestine, and liver. However, due to its limited absorption in the gastrointestinal tract and low blood concentration, its bioavailability is significantly reduced.

CONCLUSIONS

Thereby, SPN holds immense potential in the prevention and treatment of liver, lung and kidney complications. This review intends to provide a novel insight for further development of SPN, hoping to reveal the potential of SPN and necessity of further studies in this field.

PCR array analysis reveals a novel expression profile of ferroptosis-related genes in idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a chronic, irreversible, and fatal disease characterized by progressive interstitial lung fibrosis. Given its insidious onset and poor outcome, there is an urgent need to elucidate the molecular mechanisms underlying IPF and identify effective therapeutic targets and diagnosis and prognosis biomarkers. Ferroptosis is an iron-dependent form of programmed cell death that occurs as lipid peroxides accumulate. Growing evidence suggests that ferroptosis is important in IPF.

METHODS

Human ferroptosis PCR array was performed on IPF and control lung tissue. The differentially expressed ferroptosis-related genes (DE-FRGs) were identified, underwent functional enrichment analyses, protein-protein interaction network construction, and potential drug target prediction. The DE-FRGs were validated and their value as diagnostic and prognostic blood biomarkers were evaluated using the Gene Expression Omnibus dataset GSE28042.

RESULTS

The array identified 13 DE-FRGs. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that the DE-FRGs were mainly related to iron ion transport, blood microparticles, and oxidoreductase activity, and were involved in porphyrin metabolism, necroptosis, and the p53 signaling pathway in addition to ferroptosis. The 13 DE-FRGs were analyzed using the Drug-Gene Interaction Database to explore novel IPF therapeutic agents, yielding 42 potential drugs. Four DE-FRGs (BBC3, STEAP3, EPRS, SLC39A8) in the peripheral blood of IPF patients from the GSE28042 dataset demonstrated the same expression pattern as that observed in the lung tissue array. The receiver operating characteristic analysis demonstrated that the area under the curve of STEAP3 and EPRS were > 0.75. The survival analysis demonstrated that STEAP3 and EPRS were significantly different between the IPF and control groups.

CONCLUSIONS

The FRG expression profiles in IPF and control lung tissue were characterized. The findings provided valuable ideas to elucidate the role of ferroptosis in IPF and aided the identification of novel IPF therapeutic targets and biomarkers.

A micro-lung chip with macrophages for targeted anti-fibrotic therapy

Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease of unknown etiology. Macrophages are implicated in the fibrotic process, but exhibit remarkable plasticity in the activated immune environmentin vivo, presenting significant challenges as therapeutic targets. To explore the influence of macrophages on IPF and develop macrophage-targeted therapies, we engineered a micro-lung chip with a lung epithelium-interstitium tissue unit to establish a controlled immune environment containing only macrophages. We discovered that macrophages exacerbated inflammation and fibrosis by comparing microchips treated with bleomycin (BLM) in the presence and absence of macrophages. Based on the duration of BLM treatment, we established pathological models corresponding to inflammation and fibrosis stages. Transcriptome analysis revealed that activation of the PI3K-AKT signalling pathway facilitates the transition from inflammation to fibrosis. However, LY294002, a PI3K inhibitor, not only suppressed fibrosis and decreased the accumulation of M2 macrophages but also intensified the severity of inflammation. These findings suggest that macrophages play a pivotal role in the potential development at the tissue level. The micro-lung chip co-cultured with macrophages holds significant potential for exploring the pathological progression of IPF and elucidating the mechanisms of anti-fibrotic drugs.

A small interfering RNA inhibits lung fibroblast-myofibroblast differentiation via simultaneously knockingdown CELF1 and activating RIG-I signalling

Fibroblast-myofibroblast differentiation plays a key role in the pathogenesis of pulmonary fibrosis. Integrating RNA interference and RNA immunostimulation functions to treat diseases is a promising new potential therapy. Here, we report that an elevated expression of CUGBP Elav-Like Family Member 1 (CELF1), an RNA-binding protein, positively correlates with lung fibroblast-myofibroblast differentiation in fibrotic lung tissues. Knockdown of CELF1 expression by siRNA-17834 or siRNA-116447 inhibited lung fibroblast-myofibroblast differentiation via promoting the anti-fibrotic IL7 mRNA stability. Interestingly, siRNA-17834 but not siRNA-116447 unexpectedly induced Retinoic Acid-inducible Gene I (RIG-I) dependent IFN-β production, which also inhibited lung fibroblast-myofibroblast differentiation. In conclusion, siRNA-17834 has dual functions of RNA interference and RNA immunostimulation to control lung fibroblast-myofibroblast differentiation, which suggests a novel strategy for the treatment of pulmonary fibrosis.

Phosphorylation of FOXN3 by NEK6 promotes pulmonary fibrosis through Smad signaling

The transcriptional repressor FOXN3 plays a key role in regulating pulmonary inflammatory responses, which are crucial in the development of pulmonary fibrosis. However, its specific regulatory function in lung fibrosis remains unclear. Here, we show that FOXN3 suppresses pulmonary fibrosis by inhibiting Smad transcriptional activity. FOXN3 targets a substantial number of Smad response gene promoters, facilitating Smad4 ubiquitination, which disrupts the association of the Smad2/3/4 complex with chromatin and abolishes its transcriptional response. In response to pro-fibrotic stimuli, NEK6 phosphorylates FOXN3 at S412 and S416, leading to its degradation. The loss of FOXN3 inhibits β-TrCP-mediated ubiquitination of Smad4, stabilizing the Smad complex's association with its responsive elements and promoting transcriptional activation, thus contributing to the development of pulmonary fibrosis. Notably, we found a significant inverse expression pattern between FOXN3 and Smad4 in clinical pulmonary fibrosis cases, underscoring the importance of the NEK6-FOXN3-Smad axis in the pathological process of pulmonary fibrosis.

S1PR1-biased activation drives the resolution of endothelial dysfunction-associated inflammatory diseases by maintaining endothelial integrity

G protein-coupled sphingosine-1-phosphate receptor 1 (S1PR1), a drug target for inflammatory bowel disease (IBD), enables immune cells to egress from lymph nodes, but the treatment increases the risk of immunosuppression. The functional signaling pathway triggered by S1PR1 activation in endothelial cells and its therapeutic application remains unclear. Here, we showed that S1PR1 is highly expressed in endothelial cells of IBD patients and positively correlated with endothelial markers. Gi-biased agonist-SAR247799 activated S1PR1 and reversed pathology in male mouse and organoid IBD models by protecting the integrity of the endothelial barrier without affecting immune cell egress. Cryo-electron microscopy structure of S1PR1-Gi signaling complex bound to SAR247799 with a resolution of 3.47 Å revealed the recognition mode for the biased ligand. With the efficacy of SAR247799 in treating other endothelial dysfunction-associated inflammatory diseases, our study offers mechanistic insights into the Gi-biased S1PR1 agonist and represents a strategy for endothelial dysfunction-associated disease treatment.

Modulating NLRP3 Inflammasomes in Idiopathic Pulmonary Fibrosis: A Comprehensive Review on Flavonoid-Based Interventions

Idiopathic Pulmonary Fibrosis (IPF) is a severe, rapidly advancing disease that drastically diminishes life expectancy. Without treatment, it can progress to lung cancer. The precise etiology of IPF remains unknown, but inflammation and damage to the alveolar epithelium are widely thought to be pivotal in its development. Research has indicated that activating the NLRP3 inflammasome is a crucial mechanism in IPF pathogenesis, as it triggers the release of pro-inflammatory cytokines such as IL-1β, IL-18, and TGF-β. These cytokines contribute to the myofibroblast differentiation and extracellular matrix (ECM) accumulation. Currently, treatment options for IPF are limited. Only two FDA-approved medications, pirfenidone and nintedanib, are available. While these drugs can decelerate disease progression, they come with a range of side effects and do not cure the disease. Additional treatment strategies primarily involve supportive care and therapy. Emerging research has highlighted that numerous flavonoids derived from traditional medicines can inhibit the critical regulators responsible for activating the NLRP3 inflammasome. These flavonoids show promise as potential therapeutic agents for managing IPF, offering a new avenue for treatment that targets the core inflammatory processes of this debilitating condition.

Non-Pharmacological Management of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a relatively common progressive fibrotic interstitial lung disease associated with significant morbidity and mortality. The available medications for IPF only slow down the disease process, with lung transplantation the only option for a cure. Non-pharmacological therapies are significant adjuncts that can improve symptom burden and quality of life with minimal or no side effects. Supplemental oxygen can improve exercise capacity and the sensation of dyspnea in a significant portion of patients with resting or exertional hypoxemia and has been supported by several professional societies. Pulmonary rehabilitation is a comprehensive program that includes education and therapeutic exercises to improve patient stamina and strength. It is one of the few interventions that have been shown to produce a meaningful increase in a patient's exercise capacity, but its wide adoption is limited by availability, especially in rural areas. Sleep optimization with supplemental oxygen and positive airway pressure therapy should actively be investigated for all patients diagnosed with IPF. Although gastroesophageal reflux control with non-pharmacological means is still controversial as an intervention to reduce the rate of lung function decline, it can help control reflux symptoms and improve cough intensity. IPF patients should be educated on the importance of balanced nutrition and the potential benefits of screening for lung transplantation. Palliative medicine can help with symptom control and should be considered for all patients regardless severity, but especially in those in the later stages of disease.

Pathophysiology of small airways in idiopathic pulmonary fibrosis (IPF): the silent zone

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by distorted alveolar structure and reduced lung compliance, and impaired ventilation-perfusion. Small airway disease (SAD) is  often termed a 'quietzone' due to its asymptomatic nature. Around 30-40% of IPF patients exhibit SAD, which is associated with worse prognosis, higher fibrosis and emphysema scores, and elevated mortality risk. We used PubMed and Google Scholar for literature search.

AREAS COVERED

This review explores the pathophysiology of small airways in IPF, focusing on 1. Risk factors, including age, gender, smoking and occupational dust exposure, and ozone. 2. Diagnostic challenges: SAD is difficult to detect through traditional spirometry or high-resolution computed tomography  imaging due to resolution limitations.  3. Early physiological changes of small airways include airway wall thickening, lumen distortion, and reduced terminal bronchioles, preceding microscopic fibrosis, occurs in the early process of IPF. 4. Pathological mechanisms: The review examines the underlying mechanisms driving small airway disease in IPF.

EXPERT OPINION

A comprehensive approach is essential to improve the understanding and management of SAD in IPF. Priorities include identifying therapeutic targets, advanced imaging and functional assessments. Forced oscillation technique should be introduced for early detection for small airway abnormalities in IPF.

Biomaterial-based 3D human lung models replicate pathological characteristics of early pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and incurable lung disease characterized by tissue scarring that disrupts gas exchange. Epithelial cell dysfunction, fibroblast activation, and excessive extracellular matrix deposition drive this pathology that ultimately leads to respiratory failure. Mechanistic studies have shown that repeated injury to alveolar epithelial cells initiates an aberrant wound-healing response in surrounding fibroblasts through secretion of mediators like transforming growth factor-β, yet the precise biological pathways contributing to disease progression are not fully understood. To better study these interactions there is a critical need for lung models that replicate the cellular heterogeneity, geometry, and biomechanics of the distal lung microenvironment. In this study, induced pluripotent stem cell-derived alveolar epithelial type II (iATII) cells and human pulmonary fibroblasts were arranged to replicate human lung micro-architecture and embedded in soft or stiff poly(ethylene glycol) norbornene (PEG-NB) hydrogels that recapitulated the mechanical properties of healthy and fibrotic lung tissue, respectively. The co-cultured cells were then exposed to pro-fibrotic biochemical cues, including inflammatory cytokines and growth factors. iATIIs and fibroblasts exhibited differentiation pathways and gene expression patterns consistent with trends observed during IPF progression in vivo. A design of experiments statistical analysis identified stiff hydrogels combined with pro-fibrotic biochemical cue exposure as the most effective condition for modeling fibrosis in vitro. Finally, treatment with Nintedanib, one of only two Food and Drug Administration (FDA)-approved drugs for IPF, was assessed. Treatment reduced fibroblast activation, as indicated by downregulation of key activation genes, and upregulated several epithelial genes. These findings demonstrate that human 3D co-culture models hold tremendous potential for advancing our understanding of IPF and identifying novel therapeutic targets.

Air pollution, metabolic signatures, and the risk of idiopathic pulmonary fibrosis

Air pollution has been associated with a higher incidence of idiopathic pulmonary fibrosis (IPF), yet this metabolic mechanism remains unclear. 185,865 participants were included in the UK Biobank. We estimated air pollution exposure using the bilinear interpolation approach, including fine particle matter with diameter < 2.5 μm (PM2.5), particle matter with diameter < 10 μm (PM10), nitrogen dioxide (NO2), and nitrogen oxides (NOx). We identified metabolites and established the metabolic signature with air pollutants using an elastic net regularized regression. Cox proportional hazards models combined with generalized propensity score (GPS) were conducted to evaluate the relationships between metabolic signatures and incident IPF, and mediation analysis was performed to evaluate potential mediators. During a median follow-up of 12.3 years, 1239 IPF cases were ascertained. We identified multi-metabolite profiles comprising 87 metabolites for PM2.5, 65 metabolites for PM10, 71 metabolites for NO2, and 76 metabolites for NOx. Metabolic signatures were associated with incident IPF, with HRs of 1.20 (95 % CI: 1.13, 1.27), 1.09 (95 % CI: 1.03, 1.15), 1.23 (95 % CI: 1.16, 1.31), and 1.24 (95 % CI: 1.17, 1.31) per standard deviation (SD) increase in metabolic profiles associated with PM2.5, PM10, NO2, and NOx, respectively. Furthermore, metabolic signatures of PM2.5, PM10, NO2 and NOx significantly mediated 5.71 %, 3.98 %, 4.21 %, and 4.58 % of air pollution on IPF. Long-term air pollution was associated with a higher risk of IPF, with metabolites potentially playing a mediating role. The findings emphasize the significance of improving metabolic status for the prevention of IPF.

Contribution of cuproptosis and immune-related genes to idiopathic pulmonary fibrosis disease

Background

Idiopathic pulmonary fibrosis (IPF) is a degenerative respiratory condition characterized by significant mortality rates and a scarcity of available treatment alternatives. Cuproptosis, a novel form of copper-induced cell death, has garnered attention for its potential implications. The study aimed to explore the diagnostic value of cuproptosis-related hub genes in patients with IPF. Additionally, multiple bioinformatics analyses were employed to identify immune-related biomarkers associated with the diagnosis of IPF, offering valuable insights for future treatment strategies.

Methods

Four microarray datasets were selected from the Gene Expression Omnibus (GEO) collection for screening. Differentially expressed genes (DEGs) associated with IPF were analyzed. Additionally, weighted gene coexpression network analysis (WGCNA) was employed to identify the DEGs most associated with IPF. Ultimately, we analyzed five cuproptosis-related hub genes and assessed their diagnostic value for IPF in both the training and validation sets. Additionally, four immune-related hub genes were screened using a protein-protein interaction (PPI) network and evaluated through the receiver operating characteristic (ROC) curve. Lastly, single-cell RNA-seq was employed to further investigate differential gene distribution.

Results

We identified a total of 92 DEGs. Bioinformatics analysis highlighted five cuproptosis-related genes as candidate biomarkers, including three upregulated genes (CFH, STEAP1, and HDC) and two downregulated genes (NUDT16 and FMO5). The diagnostic accuracy of these five genes in the cohort was confirmed to be reliable. Additionally, we identified four immune-related hub genes that demonstrated strong diagnostic performance for IPF, with CXCL12 showing an AUROC of 0.90. We also examined the relationship between these four genes and immune cells. CXCL12 was significantly negatively associated with neutrophils, while CXCR2 was associated exclusively with neutrophils, consistent with our single-cell sequencing results. CTSG showed a primarily positive association with follicular helper T, and SPP1 was most strongly associated with macrophages. Finally, our single-cell sequencing data revealed that in patients with IPF, CXCL12 was highly expressed in the endothelial cell subset (ECs), while SPP1 exhibited high expression in multiple cellular populations. The expression of the CTSG showed statistically significant differences in monocyte macrophages.

Conclusion

The research methodically depicted the intricate interplay among five cuproptosis-related genes, four immune-related hub genes, and IPF, offering new ideas for diagnosing and treating patients with IPF.

CD109, a master regulator of inflammatory responses

Inflammation is a complex response to harmful stimuli, crucial for immunity, and linked to chronic diseases and cancer, with TGF-β and NF-κB pathways as key regulators. CD109 is a glycosylphosphatidylinositol (GPI)-anchored protein, that our group has originally identified as a TGF-β co-receptor and inhibitor of TGF-β signaling. CD109 modulates TGF-β and NF-κB pathways, to influence immune responses and inflammation. CD109's multifaceted role in inflammation spans various tissue types, including the skin, lung, bone and bone-related tissues, and various types of cancers. CD109 exerts its effects by modulating processes such as cytokine secretion, immune cell recruitment, macrophage polarization, T helper cell function and cancer cell phenotype and function. Here, we review CD109's regulatory functions in inflammatory responses in these various tissues and cell types. Exploration of CD109's mechanisms of action will enhance our understanding of its contributions to disease pathology and its potential for therapeutic applications.

Comparison of the Effects of Nintedanib and Pirfenidone on Pulmonary Function Test Parameters and Radiological Findings in Patients with Idiopathic Pulmonary Fibrosis: A Real-Life Study

Background and Objectives: The aim of our study is to compare the effects of pirfenidone and nintedanib on lung function and radiologic findings in Idiopathic Pulmonary Fibrosis and to identify which drug is more appropriate for which patient group. Materials and Methods: The data of patients who were treated in our department for at least one year between 1 January 2010 and 31 December 2022 and who were started on pirfenidone or nintedanib treatment with the diagnosis of Idiopathic Pulmonary Fibrosis were retrospectively reviewed. The patients were divided into two groups-the nintedanib and pirfenidone groups-and both groups were compared in terms of progression in lung function tests (changes in FEV1, FVC, 6 MWT and DLCO values at the 3rd, 6th, 9th and 12th months compared to baseline values) and radiological findings (the presence of progression in findings such as ground-glass opacity, reticulation, honeycomb and traction bronchiectasis) within 1 year after diagnosis. Results: The study included 109 patients. The number of patients treated with pirfenidone (IPF patients) was 82 (75.2%) and the number of patients treated with nintedanib was 27 (24.8%). When the PFT values at 3, 6, 9 and 12 months were compared with the baseline values in both groups, there was no statistically significant difference in any parameter between the two groups. No significant difference was found in terms of radiological progression at the end of 1 year in both groups. Conclusions: The results of our study show that pirfenidone and nintedanib are equivalent in their effectiveness in preventing disease progression in patients with IPF.

The role of natural products targeting macrophage polarization in sepsis-induced lung injury

Sepsis-induced acute lung injury (SALI) is characterized by a dysregulated inflammatory and immune response. As a key component of the innate immune system, macrophages play a vital role in SALI, in which a macrophage phenotype imbalance caused by an increase in M1 macrophages or a decrease in M2 macrophages is common. Despite significant advances in SALI research, effective drug therapies are still lacking. Therefore, the development of new treatments for SALI is urgently needed. An increasing number of studies suggest that natural products (NPs) can alleviate SALI by modulating macrophage polarization through various targets and pathways. This review examines the regulatory mechanisms of macrophage polarization and their involvement in the progression of SALI. It highlights how NPs mitigate macrophage imbalances to alleviate SALI, focusing on key signaling pathways such as PI3K/AKT, TLR4/NF-κB, JAK/STAT, IRF, HIF, NRF2, HMGB1, TREM2, PKM2, and exosome-mediated signaling. NPs influencing macrophage polarization are classified into five groups: terpenoids, polyphenols, alkaloids, flavonoids, and others. This work provides valuable insights into the therapeutic potential of NPs in targeting macrophage polarization to treat SALI.

Idiopathic Pulmonary Fibrosis: In Silico Therapeutic Potential of Doxycycline, Pirfenidone, and Nintedanib, and the Role of Next-Generation Phenomics in Drug Discovery

Innovation in drug discovery for human diseases stands to benefit from systems science and next-generation phenomics approaches. An example is idiopathic pulmonary fibrosis (IPF) that is a chronic pulmonary disorder leading to respiratory failure and for which preventive and therapeutic medicines are sorely needed. Matrix metalloproteinases (MMPs), particularly MMP1 and MMP7, have been associated with IPF pathogenesis and are thus relevant to IPF drug discovery. This study evaluates the comparative therapeutic potentials of doxycycline, pirfenidone, and nintedanib in relation to MMP1 and MMP7 using molecular docking, molecular dynamics simulations, and a next-generation phenomics approach. Adsorption, distribution, metabolism, excretion, and toxicity analysis revealed that doxycycline and nintedanib adhered to Lipinski's rule of five, while pirfenidone exhibited no violations. The toxicity analysis revealed favorable safety profiles, with lethal dose 50 values of doxycycline, pirfenidone, and nintedanib being 2240kg, 580, and 500 mg/kg, respectively. Homology modeling validated the accuracy of the structures of the target proteins, that is, MMP1 and MMP7. The Protein Contacts Atlas tool, a next-generation phenomics platform that broadens the scope of phenomics research, was employed to visualize protein contacts at atomic levels, revealing interaction surfaces in MMP1 and MMP7. Docking studies revealed that nintedanib exhibited superior binding affinities with the candidate proteins (-6.9 kcal/mol for MMP1 and -7.9 kcal/mol for MMP7) compared with doxycycline and pirfenidone. Molecular dynamics simulations further demonstrated the stability of protein-ligand complexes. These findings highlight the notable potential of nintedanib in relation to future IPF therapeutics innovation. By integrating in silico and a next-generation phenomics approach, this study opens up new avenues for drug discovery and development for IPF and possibly, for precision/personalized medicines that consider the molecular signatures of therapeutic candidates for each patient.

Epithelial stem cells from human small bronchi offer a potential for therapy of idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a fibrosing interstitial pneumonia with restrictive ventilation. Recently, the structural and functional defects of small airways have received attention in the early pathogenesis of IPF. This study aimed to elucidate the characteristics of small airway epithelial dysfunction in patients with IPF and explore novel therapeutic interventions to impede IPF progression by targeting the dysfunctional small airways.

METHODS

Airway trees spanning the proximal-distal axis were harvested from control lungs and explanted lungs with end-stage IPF undergoing transplant. Qualified basal cells (BCs, p63/Krt5/ITGA6/NGFR) were expanded, and their cellular functions, feasibility, safety and efficacy for transplantation therapy in IPF were validated with experiments in vitro and mouse model. Single-cell RNA-sequencing was employed to elucidate the underlying mechanisms governing the BCs based therapy. Based upon these evidences, three patients with advanced IPF and small airway dysfunction received autologous-BCs transplantation. Post-transplantation assessments included lung function, exercise capacity and high resolution computed tomography (HRCT) scans were analyzed to quantify the clinical benefits conferred by the BCs transplantation.

FINDINGS

An overall landscape of senescent phenotype in airway epithelial cells and airway stem/progenitor cells along the proximal-distal axis of the airway tree in IPF were outlined. In contrast to the cells situated in distal airways, BCs located in small bronchi in IPF displayed a non-senescent phenotype, with comparable proliferative, differentiative capabilities, and similar transcriptomic profiles to normal controls. In a mouse model of pulmonary fibrosis, BCs exhibited promising protective efficacy and safety for transplantation therapy. Autologous BCs transplantation in three advanced IPF patients with small airway dysfunction yielded significant clinical improvements in pulmonary function, particularly evidence in lung volume and small airway function.

INTERPRETATION

Epithelia of small bronchi in IPF contain functional and expandable basal stem cells, which exert therapeutic benefits via bronchoscopic implantation. Our findings offer a potential for IPF treatment by targeting small airways.

FUNDING

National Natural Science Foundation of China (82430001, 81930001, and 81900059), Shanghai Shenkang Hospital Development Center (SHDC2020CR3063B), Department of Science and Technology of Shandong Province (2024HWYQ-058).

Pharmacokinetics and safety of pirfenidone in individuals with chronic kidney disease stage G2 and G3a: A single-dose, Phase I, bridging study

BACKGROUND AND OBJECTIVE

Pirfenidone is an inhibitor of transforming growth factor-beta 1 (TGF-β1) and is being developed for the treatment of diabetic kidney disease (DKD). We assessed the pharmacokinetics (PK) and safety of a single dose of pirfenidone in individuals with CKD stages G2/G3a.

METHODS

In this phase I bridging study, patients with CKD stages G2 or G3a, aged 18-70 years, with a body mass index of 18-26 kg/m2, and glomerular filtration rate (eGFR) ranging from 45 to 89 ml/min/1.73 m2, received a single oral dose of 400 mg pirfenidone capsules 30 min after a standard breakfast. The pharmacokinetic parameters of the two groups were measured and compared after blood and urine collection. The co-primary endpoints were the area under the plasma concentration-time curve from time zero to 36 h (AUC0-36) and the maximum observed plasma concentration (Cmax) of pirfenidone. Safety was a secondary endpoint. The trial has been registered on ClinicalTrials.gov (ChiCTR2300077297).

RESULTS

A total of 20 subjects participated in this study. There were no significant differences between the control group and the patient group (CKD stages G2/G3a) in terms of plasma Cmax, the time to reach the maximum observed concentration (Tmax), and elimination half-life(t1/2). However, the Vz/F of the patient group (CKD G2 stage) was significantly higher than that of the control group. Renal accumulation rate, renal clearance rate (CLr), and urine drug concentration also showed no significant differences. No severe adverse events occurred during the trial.

CONCLUSIONS

These results indicate that the PK and safety of pirfenidone are not influenced by renal function. Individuals with renal impairment may not require dose adjustments.

Single Cell RNA-Seq Identifies Cell Subpopulations Contributing to Idiopathic Pulmonary Fibrosis in Humans

The cell populations, particularly subpopulations, involved in the onset and progression of idiopathic pulmonary fibrosis (IPF) remain incompletely understood. This study employed single-cell RNA-seq to identify cell populations and subpopulations with significantly altered proportions in the lungs of patients with IPF. In IPF lungs, endothelial cell proportions were significantly increased, while alveolar epithelial cell proportions were markedly decreased. Among the three identified fibroblast subpopulations, the proportion of myofibroblasts was significantly increased, while the proportions of the other two fibroblast subtypes were reduced. Similarly, within the three macrophage subpopulations, the macrophage_SPP1 subpopulation, localised to fibroblastic foci, showed a significant increase in proportion, while the alveolar macrophage subpopulation was significantly reduced. Trajectory analysis revealed that fibroblasts in IPF lungs could differentiate into myofibroblasts, and alveolar macrophages could transition into the macrophage_SPP1 subpopulation. Among T-cell subpopulations, only the CD4 T_FOXP3 subpopulation exhibited a significant change, whereas all four B-cell subpopulations showed significant proportional shifts. These findings provide a comprehensive view of the cellular alterations contributing to IPF pathogenesis. Extensive interactions among various cell populations and subpopulations were identified. The proportions of various cell populations and subpopulations in IPF lungs, including endothelial cells, fibroblasts, macrophages and B cells, were significantly altered. Further in-depth investigation into the roles of cell subpopulations with significantly altered proportions in the onset and progression of IPF will provide valuable insights into the pathological mechanisms underlying the disease. This understanding could facilitate the development of novel therapeutic strategies and medications for IPF treatment.

Material-driven immunomodulation and ECM remodeling reverse pulmonary fibrosis by local delivery of stem cell-laden microcapsules

Recent progress in stem cell therapy has demonstrated the therapeutic potential of intravenous stem cell infusions for treating the life-threatening lung disease of pulmonary fibrosis (PF). However, it is confronted with limitations, such as a lack of control over cellular function and rapid clearance by the host after implantation. In this study, we developed an innovative PF therapy through tracheal administration of microfluidic-templated stem cell-laden microcapsules, which effectively reversed the progression of inflammation and fibrotic injury. Our findings highlight that hydrogel microencapsulation can enhance the persistence of donor mesenchymal stem cells (MSCs) in the host while driving MSCs to substantially augment their therapeutic functions, including immunoregulation and matrix metalloproteinase (MMP)-mediated extracellular matrix (ECM) remodeling. We revealed that microencapsulation activates the MAPK signaling pathway in MSCs to increase MMP expression, thereby degrading overexpressed collagen accumulated in fibrotic lungs. Our research demonstrates the potential of hydrogel microcapsules to enhance the therapeutic efficacy of MSCs through cell-material interactions, presenting a promising yet straightforward strategy for designing advanced stem cell therapies for fibrotic diseases.

Interstitial lung disease in rheumatic diseases: an update of the 2018 review

INTRODUCTION

Interstitial lung disease (ILD) is a potential severe complication of various rheumatic diseases, typically connective tissue diseases (CTD), associated with significant morbidity and mortality. ILD may occur during the course of the disease but may also be its first manifestation. Several cell types are involved in ILD's pathogenesis, and if not controlled, pulmonary inflammation may lead to pulmonary fibrosis.

AREAS COVERED

We searched PubMed, Medline, and the Cochrane Library for papers published between 1995 and February 2017 in the first version, and between 2017 and April 2023 using combinations of words. The most frequent systemic rheumatic diseases associated with ILD are systemic sclerosis (SSc), rheumatoid arthritis (RA), and idiopathic inflammatory myositis. Treatment and monitoring guidelines are still lacking, and current treatment strategies have been extrapolated from the literature on SSc and established treatments for non-pulmonary systemic rheumatic manifestations.

EXPERT OPINION

Given the complexity of diagnosis and the paucity of treatment trials, managing CTD patients with ILD is challenging. It requires the skills of multidisciplinary CTD-ILD clinics including at least rheumatologists and lung specialists.

Muribaculum intestinale-derived 3-hydroxybutyric acid from Heterophyllin B attenuated pulmonary fibrosis through IDO1-mediated ferroptosis

Pulmonary fibrosis (PF) is a fatal disease with increasing incidence, poor prognosis, and unclear pathogenesis. Our previous research demonstrated the beneficial effects of the natural cyclopeptide Heterophyllin B (HB) in PF. However, the precise mechanism by which HB exerts its effects in PF remains unclear. Our study revealed HB's beneficial effects in alleviating PF symptoms and restoring the intestinal mucosal barrier. Subsequently, the microbiota-dependent antifibrotic efficacy of HB was verified using various delivery routes, antibiotic treatments, and faecal microbiota transplantation. Functionally, 16S rRNA sequencing, untargeted metabolomics, and co-incubation experiments revealed that the antifibrotic efficacy of HB was primarily contingent on the enrichment of Muribaculum intestinale and its metabolite, 3-hydroxybutyric acid. Mechanistically, indoleamine 2,3- dioxygenase 1 (IDO1)-mediated ferroptosis was identified as a pivotal process in initiating PF, and the anti-fibrotic efficacy of HB relies on suppressing IDO1-mediated ferroptosis. Conversely, IDO1 deficiency alleviated the symptoms of bleomycin-induced PF and ferroptosis in mice. Coincidentally, both IDO1 overexpression and ferroptosis were observed in the pulmonary tissue of patients with idiopathic PF. Collectively, this study revealed that HB alleviates PF by eliminating intestinal microecology and metabolism and highlights the feasibility of targeting IDO1 for PF treatment.

Cell therapy: A beacon of hope in the battle against pulmonary fibrosis

Pulmonary fibrosis (PF) is a chronic and progressive interstitial lung disease characterized by abnormal activation of myofibroblasts and pathological remodeling of the extracellular matrix, with a poor prognosis and limited treatment options. Lung transplantation is currently the only approach that can extend the life expectancy of patients; however, its applicability is severely restricted due to donor shortages and patient-specific limitations. Therefore, the search for novel therapeutic strategies is imperative. In recent years, stem cells have shown great promise in the field of regenerative medicine due to their self-renewal capacity and multidirectional differentiation potential, and a growing body of literature supports the efficacy of stem cell therapy in PF treatment. This paper systematically summarizes the research progress of various stem cell types in the treatment of PF. Furthermore, it discusses the primary methods and clinical outcomes of stem cell therapy in PF, based on both preclinical and clinical data. Finally, the current challenges and key factors to consider in stem cell therapy for PF are objectively analyzed, and future directions for improving this therapy are proposed, providing new insights and references for the clinical treatment of PF patients.

The Multifaceted Roles of BACH1 in Disease: Implications for Biological Functions and Therapeutic Applications

BTB domain and CNC homolog 1 (BACH1) belongs to the family of basic leucine zipper proteins and is expressed in most mammalian tissues. It can regulate its own expression and play a role in transcriptionally activating or inhibiting downstream target genes. It has a crucial role in various biological processes, such as oxidative stress, cell cycle, heme homeostasis, and immune regulation. Recent research highlights BACH1's significant regulatory roles in a series of conditions, including stem cell pluripotency maintenance and differentiation, growth, senescence, and apoptosis. BACH1 is closely associated with cardiovascular diseases and contributes to angiogenesis, atherosclerosis, restenosis, pathological cardiac hypertrophy, myocardial infarction, and ischemia/reperfusion (I/R) injury. BACH1 promotes tumor cell proliferation and metastasis by altering tumor metabolism and the epithelial-mesenchymal transition phenotype. Moreover, BACH1 appears to show an adverse role in diseases such as neurodegenerative diseases, gastrointestinal disorders, leukemia, pulmonary fibrosis, and skin diseases. Inhibiting BACH1 may be beneficial for treating these diseases. This review summarizes the role of BACH1 and its regulatory mechanism in different cell types and diseases, proposing that precise targeted intervention of BACH1 may provide new strategies for human disease prevention and treatment.

Exploring TβRI inhibitors from Arenaria kansuensis based on 3D-QSAR, molecular docking and molecular dynamics simulation methods and its anti-pulmonary fibrosis molecular mechanism validation

ETHNOPHARMACOLOGICAL RELEVANCE

Pulmonary fibrosis (PF) is a kind of interstitial lung disease that seriously threatens human life and health. Up to now, there is no specifically therapeutic drug. Arenaria kansuensis, a typical Tibetan medicine, has been previously proved to have anti-PF pharmacological activity by our group. However, the specific target and molecular mechanism of pharmacological active ingredients from it are still unknown.

AIM OF THE STUDY

This study aimed to explore the molecular mechanism and specific target of pharmacological active ingredients from A. kansuensis for treating PF.

MATERIALS AND METHODS

Virtual screening including 3D-QSAR, molecular docking and molecular dynamics simulation were used to screen TβRI inhibitor. CETSA experiment was used to verify the interaction between GAK (a β-carboline alkaloid isolated from A. kansuensis) and TβRI. Cell and molecular experiments including observation of cell morphology and Western blot were applied to investigate the molecular mechanism of action of GAK for treating PF. Animal experiments including physiological index, immunohistochemistry and ELISA were used to comprehensively evaluate the anti-PF effect of GAK and explore the corresponding mechanism of action.

RESULTS

Results of 3D-QSAR experiment indicated that GAK is a much stronger potential TβRI inhibitor, molecular mechanism study showed that 30 μM GAK could significantly keep TβRI more stable which indicated that the direct binding interaction between GAK and TβRI, it targetedly inhibited TβRI through forming hydrogen bonds with LYS232, SER280 and ASP351 and the binding energies is -56.05 kcal/mol. In vitro experiment showed GAK could suppress downstream signal pathways of TβRI including MAPK, PI3K/AKT and NF-κB pathways during EMT process. In vivo experiment showed that GAK could improve the survival rate and body weight of PF mice, alleviate the symptoms of histopathological severity, inflammatory cell infiltration and collagen deposition in lung tissue of PF mice through inhibiting EMT process of PF.

CONCLUSIONS

This work not only provided evidence to support GAK as a novel TβRI inhibitor for treating PF through multiple pathways, but also reveal the specific target and molecular mechanism of β-carboline alkaloids from A. kansuensis for treating PF.

The Relationship Between Differential Expression of Non-coding RNAs (TP53TG1, LINC00342, MALAT1, DNM3OS, miR-126-3p, miR-200a-3p, miR-18a-5p) and Protein-Coding Genes (PTEN, FOXO3) and Risk of Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a rapidly progressive interstitial lung disease of unknown pathogenesis with no effective treatment currently available. Given the regulatory roles of lncRNAs (TP53TG1, LINC00342, H19, MALAT1, DNM3OS, MEG3), miRNAs (miR-218-5p, miR-126-3p, miR-200a-3p, miR-18a-5p, miR-29a-3p), and their target protein-coding genes (PTEN, TGFB2, FOXO3, KEAP1) in the TGF-β/SMAD3, Wnt/β-catenin, focal adhesion, and PI3K/AKT signaling pathways, we investigated the expression levels of selected genes in peripheral blood mononuclear cells (PBMCs) and lung tissue from patients with IPF. Lung tissue and blood samples were collected from 33 newly diagnosed, treatment-naive patients and 70 healthy controls. Gene expression levels were analyzed by RT-qPCR. TaqMan assays and TaqMan MicroRNA assay were employed to quantify the expression of target lncRNAs, mRNAs, and miRNAs. Our study identified significant differential expression in PBMCs from IPF patients compared to healthy controls, including lncRNAs MALAT1 (Fold Change = 3.809, P = 0.0001), TP53TG1 (Fold Change = 0.4261, P = 0.0021), and LINC00342 (Fold Change = 1.837, P = 0.0448); miRNAs miR-126-3p (Fold Change = 0.102, P = 0.0028), miR-200a-3p (Fold Change = 0.442, P = 0.0055), and miR-18a-5p (Fold Change = 0.154, P = 0.0034); and mRNAs FOXO3 (Fold Change = 4.604, P = 0.0032) and PTEN (Fold Change = 2.22, P = 0.0011). In lung tissue from IPF patients, significant expression changes were observed in TP53TG1 (Fold Change = 0.2091, P = 0.0305) and DNM3OS (Fold Change = 4.759, P = 0.05). Combined analysis of PBMCs expression levels for TP53TG1, MALAT1, miRNA miR-126-3p, and PTEN distinguished IPF patients from healthy controls with an AUC = 0.971, sensitivity = 0.80, and specificity = 0.955 (P = 6 × 10-8). These findings suggest a potential involvement of the identified ncRNAs and mRNAs in IPF pathogenesis. However, additional functional validation studies are needed to elucidate the precise molecular mechanisms by which these lncRNAs, miRNAs, and their targets contribute to PF.

Inhibition of HIF-1α ameliorates pulmonary fibrosis by suppressing M2 macrophage polarization through PRMT1/STAT6 signals

OBJECTIVE

Pulmonary fibrosis (PF) is a chronic, progressive, and irreversible lung interstitial disease of unknown etiology with a fatal outcome. M2 macrophages have been recognized to play a significant role in PF pathogenesis. The role of protein hypoxia-inducible factor 1-α (HIF-1α) in M2 macrophage polarization in PF is largely unknown. This study aimed to investigate the role of macrophage HIF-1α in the regulation of PF.

METHODS

PF was induced in C57BL/6 mice by the intratracheal injection of bleomycin (BLM), and small hairpin RNA (shRNA) lentiviral construct specifically targeting HIF-1α were designed for in vitro and in vivo experiments. In the in vitro experiment, bone marrow-derived macrophages (BMDMs) were used to explore molecular mechanism analysis. In the in vivo experiment, mice were administered BLM intratracheally on day 0, treated with shRNA on day 7, and sacrificed on day 21. Histopathological techniques (H&E and Masson's trichrome staining) were used to evaluate PF severity. Western blot, immunofluorescence, quantitative real-time PCR, and flow cytometry were performed to explore the underlying mechanisms.

RESULTS

HIF-1α was upregulated and macrophages polarized toward M2 phenotype in BLM-induced mouse pulmonary fibrosis models. By constructing HIF-1α knockdown shRNA lentiviral construct, we found that the knockdown of HIF-1α in macrophages significantly suppressed M2-type polarization in vitro, hence alleviating fibrosis in lung epithelial cells. Further results revealed that HIF-1α in macrophages promoted M2-type polarization by mediating the signal transducer and activator of transcription 6 (STAT6) arginine methylation. Meanwhile, its arginine methylation modification site is at position Arg27. Further experiments indicated that the regulation of STAT6 arginine methylation by HIF-1α mainly depended on the protein arginine methyltransferase 1 (PRMT1). Finally, animal experiments demonstrated that Knockdown of HIF-1α, PRMT1, and STAT6 relieved the BLM-induced pulmonary fibrosis of mice.

CONCLUSION

HIF-1α may act as a novel factor to promote macrophage of the M2 program. Therapeutic approaches to target macrophage HIF-1α may act as a new therapeutic strategy to combat PF in the future.

Special Issue "Molecular Advances and Perspectives of Lung Disease"

Respiratory diseases represent a significant global public health challenge, contributing to high mortality and morbidity rates worldwide [...].

Nitazoxanide alleviates experimental pulmonary fibrosis by inhibiting the development of cellular senescence

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease characterized by irreversible lung scarring with a poor prognosis. Emerging evidence has revealed that IPF is an aging-related disease, and the development of cellular senescence plays a pivotal role in persistent remodeling and fibrotic scarring, acting as a key mechanism in the pathophysiology of IPF. Exploring therapeutic strategies for modulating cellular senescence can provide crucial insights into unraveling IPF processes. Here, we have identified Nitazoxanide (NTZ), an FDA-approved antiprotozoal agent, has specific effects on inhibiting cellular senescence development. In the bleomycin and D-galactose-induced senescence model, NTZ effectively inhibits senescence associated-β-gal staining and preserves cell proliferation ability. We also found that NTZ effectively impedes senescence progression in the bleomycin-induced pulmonary fibrosis model, while mitigating the release of senescence-associated secretory phenotype and alleviating pulmonary fibrosis. The anti-senescence effect of NTZ is mechanistically dependent on the preservation of nuclear SIRT1 expression. We observed that PI3K induces a WIPI1-mediated nucleophagic degradation of SIRT1, while NTZ effectively inhibits PI3K and suppresses WIPI1 expression, thereby maintaining SIRT1 expression in the nucleus and exerting its anti-senescence function. Collectively, our research has shown that NTZ can inhibit PI3K in senescence progression, leading to the inhibition of WIPI1-mediated SIRT1 nucleophagic degradation. As a result, NTZ alleviates fibrosis by inhibiting senescence development.

Advances in Selenium and Related Compounds Inhibiting Multi-Organ Fibrosis

Selenium (Se), a critically essential trace element, plays a crucial role in diverse physiological processes within the human body, such as oxidative stress response, inflammation regulation, apoptosis, and lipid metabolism. Organ fibrosis, a pathological condition caused by various factors, has become a significant global health issue. Numerous studies have demonstrated the substantial impact of Se on fibrotic diseases. This review delves into the latest research advancements in Se and Se-related biological agents for alleviating fibrosis in the heart, liver, lungs, and kidneys, detailing their mechanisms of action within fibrotic pathways. Additionally, the article summa-rizes some of the anti-fibrotic drugs currently in clinical trials for the aforementioned organ fibroses.

PLAC8 attenuates pulmonary fibrosis and inhibits apoptosis of alveolar epithelial cells via facilitating autophagy

Idiopathic pulmonary fibrosis (IPF) is an irreversible lung condition that progresses over time, which ultimately results in respiratory failure and mortality. In this study, we found that PLAC8 was downregulated in the lungs of IPF patients based on GEO data, in bleomycin (BLM)-induced lungs of mice, and in primary murine alveolar epithelial type II (pmATII) cells and human lung epithelial cell A549 cells. Overexpression of PLAC8 facilitated autophagy and inhibited apoptosis of pmATII cells and A549 cells in vitro. Moreover, inhibition of autophagy or overexpression of p53 partially abolished the effects of PLAC8 on cell apoptosis. ATII cell-specific overexpression of PLAC8 alleviated BLM-induced pulmonary fibrosis in mice. Mechanistically, PLAC8 interacts with VCP-UFD1-NPLOC4 complex to promote p53 degradation and facilitate autophagy, resulting in inhibiting apoptosis of alveolar epithelial cells and attenuating pulmonary fibrosis. In summary, these findings indicate that PLAC8 may be a key target for therapeutic interventions in pulmonary fibrosis.

The bronchoalveolar lavage fluid CD44 as a marker for pulmonary fibrosis in diffuse parenchymal lung diseases

Introduction

Diffuse parenchymal lung diseases (DPLD) cover heterogeneous types of lung disorders. Among many pathological phenotypes, pulmonary fibrosis is the most devastating and represents a characteristic sign of idiopathic pulmonary fibrosis (IPF). Despite a poor prognosis brought by pulmonary fibrosis, there are no specific diagnostic biomarkers for the initial development of this fatal condition. The major hallmark of lung fibrosis is uncontrolled activation of lung fibroblasts to myofibroblasts associated with extracellular matrix deposition and the loss of both lung structure and function.

Methods

Here, we used this peculiar feature in order to identify specific biomarkers of pulmonary fibrosis in bronchoalveolar lavage fluids (BALF). The primary MRC-5 human fibroblasts were activated with BALF collected from patients with clinically diagnosed lung fibrosis; the activated fibroblasts were then washed rigorously, and further incubated to allow secretion. Afterwards, the secretomes were analysed by mass spectrometry.

Results

In this way, the CD44 protein was identified; consequently, BALF of all DPLD patients were positively tested for the presence of CD44 by ELISA. Finally, biochemical and biophysical characterizations revealed an exosomal origin of CD44. Receiver operating characteristics curve analysis confirmed CD44 in BALF as a specific and reliable biomarker of IPF and other types of DPLD accompanied with pulmonary fibrosis.

An FGF2-Derived Short Peptide Attenuates Bleomycin-Induced Pulmonary Fibrosis by Inhibiting Collagen Deposition and Epithelial-Mesenchymal Transition via the FGFR/MAPK Signaling Pathway

Following the COVID-19 pandemic, the prevalence of pulmonary fibrosis has increased significantly, placing patients at higher risk and presenting new therapeutic challenges. Current anti-fibrotic drugs, such as Nintedanib, can slow the decline in lung function, but their severe side effects highlight the urgent need for safer and more targeted alternatives. This study explores the anti-fibrotic potential and underlying mechanisms of an endogenous peptide (P5) derived from fibroblast growth factor 2 (FGF2), developed by our research team. Using a bleomycin-induced pulmonary fibrosis mouse model, we observed that P5 alleviated fibrosis by inhibiting collagen deposition, as confirmed by CT scans and histological staining. In TGF-β-induced cell models, P5 effectively suppressed collagen deposition and epithelial-mesenchymal transition (EMT). Transcriptome analysis highlighted pathways related to receptor binding, extracellular matrix organization, and cell adhesion, with KEGG analysis confirming FGFR/MAPK signaling inhibition as the primary mechanism underlying its anti-fibrotic effects. In summary, our study demonstrates that P5 significantly attenuates pulmonary fibrosis through the inhibition of EMT, collagen deposition, and FGFR/MAPK signaling, providing a promising therapeutic approach for fibrosis.

Comprehensive analyses of immune activity in COVID-19-vaccinated idiopathic pulmonary fibrosis patients

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease, characterized by impaired wound repair, tissue remodeling and fibrosis. Immune system may participate in the development and progression of the disease as indicated by altered activity in IPF sufferers. This study investigates the immune response to the BNT162b2 COVID-19 vaccine in patients with IPF compared to healthy controls, with a particular focus on evaluation of antibody responses, interferon-gamma release, cytokine profiling and a broad panel of immune cell subpopulations. IPF patients without prior exposure to SARS-CoV-2 had undetectable levels of anti-N IgG antibodies, highlighting their lack of previous infection. After vaccination, IPF patients showed a significant increase in anti-S1 IgG and IgA antibodies, though their levels were lower compared to healthy controls and convalescent IPF patients. Additionally, IPF patients exhibited altered proportions of regulatory T cells (Tregs) and effector T lymphocytes (Teffs) before and after vaccination. Specifically, IPF patients had higher percentages of Tregs with a Th2 phenotype and Th17 Tregs, along with reduced proportions of Th1/17 Tregs. Teffs in IPF patients showed a decrease in Th1-like and Th2-like populations after vaccination. Moreover, IPF patients demonstrated elevated populations of cytotoxic T lymphocytes (Tc) before vaccination and increased levels of γδ Tc cells throughout the study. Alterations in cytokine profiles were also observed, IPF patients showed higher levels of IL-6 and IL-22 compared to healthy controls. These findings suggest a distinct immune response in IPF patients to the COVID-19 vaccine, characterized by differences in antibody production, T cell differentiation and cytokine secretion compared to healthy individuals.

Human Umbilical Cord-Mesenchymal Stem Cells Combined With Low Dosage Nintedanib Rather Than Using Alone Mitigates Pulmonary Fibrosis in Mice

Pulmonary fibrosis (PF) is a lethal pathological change of fibrotic interstitial lung diseases (ILDs) with abundant fibroblasts proliferation after severely or continually alveolar epithelial cells (AECs) injury. Barely therapies are helpful for PF. Here we use bleomycin intratracheally injection to model PF with or without human umbilical cord-mesenchymal stem cells (hUC-MSCs) and/or nintedanib intervention. RNA-Seq followed with real-time PCR and western blot were used to find out the specific possible mechanisms of the effects of hUC-MSC and nintedanib on PF. Immunostaining, cell counting kit-8 (CCK-8), and 5-bromo-2'-deoxyuridine (BrdU) incorporation assay were used to detect the cell proliferation in vivo or in vitro separately. We found that hUC-MSCs alone had prophylactic, but not therapeutic effects on bleomycin induced mouse PF. Nevertheless, the combination therapy of hUC-MSCs and low-dose nintedanib significantly improved survival and reversed lung fibrosis in PF model mice. The factors secreted by hUC-MSCs have promotional effects on the proliferation both of fibroblasts and AECs. Nintedanib could hamper the facilitation of fibroblasts caused by hUC-MSCs without influence on AECs proliferation, which might be related with the inhibition on FGFR, PDGFR, and VEGFR activities. Our study indicated that the combination therapy of hUC-MSCs and nintedanib should be a promising strategy for PF.

Health-related quality of life and health state utility value in idiopathic pulmonary fibrosis: a systematic review and meta-analysis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is associated with high mortality, heavy economic burden, limited treatment options and poor prognosis, and seriously affects the health-related quality of life (HRQoL) and life expectancy of patients. This systematic review and meta-analysis of HRQoL and health state utility value (HSUV) in IPF patients and the instruments used in this assessment aimed to provide information sources and data support for the future research on IPF HRQoL and HSUV.

METHODS

We searched the PubMed, EMBASE, Web of Science and Cochrane Library databases for studies reporting the HRQoL or HSUV of IPF patients, with the retrieval time from the establishment of each database to April 2024. After two researchers independently screened the literature, extracted the data, and evaluated the risk of bias in the included studies, pooled analysis was performed on the measurement tools adopted in more than two studies. Subgroup analysis was employed to explore the source of heterogeneity, and sensitivity analysis was used to assess the robustness of the results. Funnel-plot directed evaluation combined with Egger's test quantitative evaluation was conducted to detect publication bias.

RESULTS

Sixty-nine studies were ultimately included, covering eighteen measurement tools. The literature quality was generally excellent. The St. George's Respiratory Questionnaire (SGRQ), EuroQoL Five Dimensions Questionnaire (EQ-5D), Short Form-36 (SF-36) and the King's Brief Interstitial Lung Disease (KBILD) were the most common instruments, among which the EQ-5D included the HSUV and the visual analog scale (VAS). The results of the meta-analysis revealed that the pooled SGRQ total score was 45.28 (95% confidence interval [CI] 41.10-49.47), the mean EQ-5D utility score was 0.75 (95% CI: 0.72-0.79), the total EQ-5D VAS score was 66.88 (95% CI: 63.75-70.01), and the pooled SF-36 physical component summary (PCS) and mental component summary (MCS) score were 36.70 (95% CI: 32.98-40.41) and 48.99 (95% CI: 47.44-50.55), respectively. The total KBILD score was 58.31 (95% CI: 55.43-61.19), the IPF specific version of the SGRQ (SGRQ-I) was 40.38 (95% CI: 28.81-51.96) and the Leicester Cough Questionnaire (LCQ) score was 16.09 (95% CI: 15.45-16.74). The pooled result of the University of California San Diego Shortness of Breath Questionnaire (USCD-SOBQ) was 45.05 (95% CI: 41.56-48.55). The results of other instruments, such as the tool to assess quality of life in IPF (ATAQ-IPF), the World Health Organization Quality of Life assessment 100 (WHOQoL-100) and the 12-item short-form health survey (SF-12) were similar to those of the above measurement tools. Regretfully, subgroup analyses did not identify the source of heterogeneity, but sensitivity analyses demonstrated robustness of our results. Except for the SGRQ total, our results showed little possibility of publication bias.

CONCLUSIONS

HRQoL in IPF patients is generally poor, and all domains are severely affected. With the aggravation of disease, HRQoL and HSUV shows a relatively downward trend, and income level is also an important factor affecting HRQoL and HSUV. At present, the published studies on IPF HRQoL and HSUV have applied many measurement tools with high interstudy heterogeneity, and future research on the optimal disease measurement tools should be strengthened. Our study provides high-quality comprehensive evidence for IPF HRQoL and HSUV, which can be used to guide clinical and economic evaluation in the future.

Ultrasonic Microfluidic Method Used for siHSP47 Loaded in Human Embryonic Kidney Cell-Derived Exosomes for Inhibiting TGF-β1 Induced Fibroblast Differentiation and Migration

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and devastating lung disorder. In response to transforming growth factor-β (TGF-β), normal lung cells proliferate and differentiate into myofibroblasts, which are instrumental in promoting disease progression. Small interfering RNA (siRNA) targeting heat shock protein 47 (HSP47) has been demonstrated to alleviate IPF by blocking collagen synthesis and secretion. Exosomes (EXOs) have been investigated for drug delivery due to their superior carrier properties. However, their loading efficiency has been a limiting factor in widely application as drug carriers. In this study, an ultrasonic microfluidic method was employed to enhance the loading efficiency of siHSP47 into EXOs, achieving 31.1% efficiency rate. EXOs were isolated from human embryonic kidney cells (293F) and loaded with siHSP47 (EXO-siHSP47). The findings indicated that EXO-siHSP47 penetrated the collagen barrier and effectively silenced HSP47 expression in activated fibroblasts in vitro. Western blotting and immunofluorescence analyses confirmed that EXO-siHSP47 significantly reduced the secretion and deposition of extracellular matrix (ECM) proteins. Wound healing and Transwell migration assays demonstrated that EXO-siHSP47 inhibited fibroblast differentiation and migration. In conclusion, 293F-derived EXOs loaded with siHSP47 present a promising therapeutic strategy for IPF.

Maternal nutrition and offspring lung health: sex-specific pathway modulation in fibrosis, metabolism, and immunity

Background

Maternal nutrition profoundly influences offspring health, impacting both prenatal and early postnatal development. Previous studies have demonstrated that maternal dietary habits can affect key developmental pathways in the offsprings, including those related to lung function and disease susceptibility. However, the sex-specific impact of a maternal high-salt diet (HSD) on offspring lung injury remains poorly understood.

Objective

This study aimed to investigate the sex-specific effects of maternal HSD on lung injury in mouse offsprings, focusing on pathways related to fibrosis, metabolism, immunity, and apoptosis.

Design

Pregnant C57BL/6J mice were subjected to either normal or HSD conditions during gestation. Lung tissues from the male and female offsprings were analyzed using high-throughput RNA sequencing and bioinformatics tools to examine transcriptomic changes. Wet-lab validation, including Masson trichrome staining, immunofluorescence for α-SMA, and qRT-PCR for fibrotic markers (α-SMA, collagen I, Fn1, and TGF-β), was conducted to confirm fibrosis and other injury markers. Lung structure and weight were also evaluated to assess physical alterations due to maternal diet.

Results

Maternal HSD significantly altered lung transcriptomes in a sex-specific manner. Male offsprings showed increased susceptibility to fibrosis, as confirmed by histological and molecular analyses, including elevated expression of α-SMA, collagen I, Fn1, and TGF-β. In contrast, female offsprings exhibited distinct changes in metabolic and immune pathways. These findings highlight the differential regulation of pulmonary injury mechanisms between male and female offsprings exposed to HSD.

Conclusions

Maternal HSD induces sex-specific lung injury in offsprings by disrupting critical pathways involved in fibrosis, metabolism, immunity, and apoptosis. The combination of transcriptomic and orthogonal data underscores the need for balanced maternal nutrition during pregnancy to promote long-term respiratory health in offsprings. These results provide new insights into the sex-specific vulnerabilities to lung disease arising from maternal diet.

Effect of ethyl acetate extract of the whole plant Clerodendrum phlomidis on improving bleomycin (BLM)-induced idiopathic pulmonary fibrosis (IPF) in Rats: In vitro and in vivo research

Idiopathic pulmonary fibrosis (IPF) is a prevalent chronic lung condition of unknown etiology characterized by fibrosis and inflammation. Lung scarring progresses owing to cytokines and immune cells that promote inflammation and fibrosis in idiopathic pulmonary fibrosis (IPF). The anti-inflammatory and anti-fibrotic properties of the ethyl acetate extract of Clerodendrum phlomidis (CPEA), derived from the Indian plant "agnimantha," are recognized in traditional Ayurvedic medicine. This study investigated the potential protective mechanisms of Clerodendrum phlomidis (CPEA), which have not been previously examined, and demonstrated how CPEA affects bleomycin (BLM)-induced lung fibrosis. Phytometabolomic analysis of Clerodendrum phlomidis was performed using UPLC-ESI-Q/TOF-MS. Free radical scavenging assays were also used to evaluate the antioxidant capacity of the plants using ABTS, DPPH, FRAP, and NO assays. Using ELISA and Griess reagent assays, we assessed the anti-inflammatory effects of CPEA in LPS-induced Jurkat, THP-1, and LL-29 cell lines. This study compared intratracheal injection of BLM-induced IPF in Wistar rats with oral administration of CPEA extract for its anti-fibrotic and anti-inflammatory properties. Multiple techniques were employed, including enzyme-linked immunosorbent assay (ELISA), hydroxyproline, histopathological, biochemical, antioxidant enzyme profiling, and hematological analyses. Polyphenolic compounds were identified using qualitative CPEA. Plant extracts demonstrated free radical-scavenging activity in vitro and exhibited antioxidant properties. CPEA extract reduced TNF-α, IL-1β, and NO levels in LPS-stimulated Jurkat, THP-1, and LL-29 cells. In response to BLM-induced lung and serum conditions in Wistar rats, the CPEA extract significantly reduced (p < 0.05) markers of inflammation and fibrosis (ALP, LDH, TNF-α, CXCL8-MIP2, MMP7, SP-A, SP-D, NO, TBARS, and MPO) and significantly restored antioxidant enzymes (p < 0.05) (GSH, GPx, and GST) and anti-inflammatory cytokines (IL10). Oral CPEA extract attenuates fibrosis, inflammation, oxidative stress, nitrosative stress, and lipid peroxidation in BLM-induced idiopathic pulmonary fibrosis (IPF). CPEA extract improved lung function and increased survival rates. Clinical trials are necessary, as this study indicated that the dietary flavonoid-rich component of CPEA extracts possesses anti-inflammatory and antioxidant properties. CPEA extract restored antioxidant enzyme levels and exerted anti-fibrotic and anti-inflammatory effects in rats with idiopathic lung fibrosis induced by BLM. CPEAs protect against lipopolysaccharide (LPS)-induced inflammation in vitro and bleomycin-induced idiopathic pulmonary fibrosis (IPF) in vivo. The findings of our investigation indicate that CPEA demonstrates therapeutic potential for IPF in human subjects, as evidenced by its capacity to enhance antioxidant, anti-inflammatory, and anti-fibrotic markers in preclinical disease models.

Deciphering the cellular and molecular landscape of pulmonary fibrosis through single-cell sequencing and machine learning

Pulmonary fibrosis is characterized by progressive lung scarring, leading to a decline in lung function and an increase in morbidity and mortality. This study leverages single-cell sequencing and machine learning to unravel the complex cellular and molecular mechanisms underlying pulmonary fibrosis, aiming to improve diagnostic accuracy and uncover potential therapeutic targets. By analyzing lung tissue samples from pulmonary fibrosis patients, we identified distinct cellular phenotypes and gene expression patterns that contribute to the fibrotic process. Notably, our findings revealed a significant enrichment of activated B cells, CD4 T cells, macrophages, and specific fibroblast subpopulations in fibrotic versus normal lung tissue. Machine learning analysis further refined these observations, resulting in the development of a diagnostic model with enhanced precision, based on key gene signatures including TMEM52B, PHACTR1, and BLVRB. Comparative analysis with existing diagnostic models demonstrates the superior accuracy and specificity of our approach. Through In vitro experiments involving the knockdown of PHACTR1, TMEM52B, and BLVRB genes demonstrated that these genes play crucial roles in inhibiting the expression of α-SMA and collagen in lung fibroblasts induced by TGF-β. Additionally, knockout of the PHACTR1 gene reduced inflammation and collagen deposition in a bleomycin-induced mouse model of pulmonary fibrosis in vivo. Additionally, our study highlights novel gene signatures and immune cell profiles associated with pulmonary fibrosis, offering insights into potential therapeutic targets. This research underscores the importance of integrating advanced technologies like single-cell sequencing and machine learning to deepen our understanding of pulmonary fibrosis and pave the way for personalized therapeutic strategies.