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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 IC 50 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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Objectives: To compare the characteristics and prognosis of patients with nontuberculous mycobacterial (NTM) pulmonary disease (PD) with pleuroparenchymal fibroelastosis (PPFE) with those of patients with nodular/bronchiectatic (NB) and fibrocavitary (FC) NTM-PD., Methods: This multicenter, retrospective, observational study enrolled 32 patients with NTM-PPFE (median age: 70.5 years, 15 females) from six institutions in Japan from January 2003 to December 2018. Their clinical characteristics and response to therapy were compared with age- and sex-matched cohorts of patients with noncavitary NB and cavitary NB/FC NTM-PD., Results: Patients with NTM-PPFE had a lower body mass index and a higher standard NTM-PD therapy initiation rate than patients with other NTM-PD types. Sputum culture conversion rates were comparable between groups; however, patients with NTM-PPFE had a higher incidence of treatment-related adverse events, including optic neuropathy associated with high-dose ethambutol therapy, lower percent predicted forced vital capacity values, higher serum Krebs von den Lungen-6 (KL-6) levels, and poorer treatment outcomes than the other groups. Cox regression revealed that NTM-PPFE was an independent risk factor for death/pneumothorax (adjusted hazard ratio: 35.3, 95% confidence interval: 3.90-4692)., Conclusion: NTM-PPFE is a unique NTM-PD phenotype with a poorer prognosis than the NB and FC phenotypes., Competing Interests: Declarations of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Pulmonary fibrosis, a disabling lung disease, results from the fibrotic transformation of lung tissue. This fibrotic transformation leads to a deterioration of lung capacity, resulting in significant respiratory distress and a reduction in overall quality of life. Currently, the frontline treatment of pulmonary fibrosis remains limited, focusing primarily on symptom relief and slowing disease progression. Bacterial infections with Pseudomonas aeruginosa are contributing to a severe progression of idiopathic pulmonary fibrosis. Phytic acid, a natural chelator of zinc, which is essential for the activation of metalloproteinase enzymes involved in pulmonary fibrosis, shows potential inhibition of LasB, a virulence factor in P. aeruginosa, and mammalian metalloproteases (MMPs). In addition, phytic acid has anti-inflammatory properties believed to result from its ability to capture free radicals, inhibit certain inflammatory enzymes and proteins, and reduce the production of inflammatory cytokines, key signaling molecules that promote inflammation. To achieve higher local concentrations in the deep lung, phytic acid was spray dried into an inhalable powder. Challenges due to its hygroscopic and low melting (25 °C) nature were mitigated by converting it to sodium phytate to improve crystallinity and powder characteristics. The addition of leucine improved aerodynamic properties and reduced agglomeration, while mannitol served as carrier matrix. Size variation was achieved by modifying process parameters and were evaluated by tools such as the Next Generation Impactor (NGI), light diffraction methods, and scanning electron microscopy (SEM). An inhibition assay for human MMP-1 (collagenase-1) and MMP-2 (gelatinase A) allowed estimation of the biological effect on tissue remodeling enzymes. The activity was also assessed with respect to inhibition of bacterial LasB. The formulated phytic acid demonstrated an IC50 of 109.7 µg/mL for LasB with viabilities > 80 % up to 188 µg/mL on A549 cells. Therefore, inhalation therapy with phytic acid-based powder shows promise as a treatment for early-stage Pseudomonas-induced pulmonary fibrosis., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Background and Purpose: Fibrotic lung remodelling after a respiratory viral infection represents a debilitating clinical sequela. Studying or managing viral-fibrotic sequela remains challenging, due to limited therapeutic options and lack of understanding of mechanisms. This study determined whether protein disulfide isomerase A3 (PDIA3) and secreted phosphoprotein 1 (SPP1), which are associated with pulmonary fibrosis, can promote influenza-induced lung fibrotic remodelling and whether inhibition of PDIA3 or SPP1 can resolve viral-mediated fibrotic remodelling., Experimental Approach: A retrospective analysis of TriNetX data sets was conducted. Serum from healthy controls and influenza A virus (IAV)-infected patients was analysed. An inhibitor of PDIA3, punicalagin, and a neutralizing antibody for SPP1 were administered in mice. Macrophage cells treated with macrophage colony-stimulating factor (M-CSF) were used as a cell culture model., Key Results: The TriNetX data set showed an increase in lung fibrosis and decline in lung function in flu-infected acute respiratory distress syndrome (ARDS) patients compared with non-ARDS patients. Serum samples revealed a significant increase in SPP1 and PDIA3 in influenza-infected patients. Lung PDIA3 and SPP1 expression increased following viral infection in mouse models. Punicalagin administration 2 weeks after IAV infection in mice caused a significant decrease in lung fibrosis and improved oxygen saturation. Administration of neutralizing SPP1 antibody decreased lung fibrosis. Inhibition of PDIA3 decreased SPP1secretion from macrophages, in association with diminished disulfide bonds in SPP1., Conclusion and Implications: The PDIA3-SPP1 axis promotes post-influenza lung fibrosis in mice and that pharmacological inhibition of PDIA3 or SPP1 can treat virus-induced lung fibrotic sequela., (© 2024 The Author(s). British Journal of Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Pulmonary fibrosis (PF) is a persistent interstitial lung condition for which effective treatment options are currently lacking. Zerumbone (zerum), a humulane sesquiterpenoid extracted from Zingiber zerumbet Smith, has been documented in previous studies to possess various pharmacological benefits. The aim of this study was to observe and investigate the therapeutic effects and mechanisms of zerum on pulmonary fibrosis. We utilized a transforming growth factor (TGF)-β1-induced human lung fibroblast (MRC-5) activation model and a bleomycin-induced pulmonary fibrosis mouse model. Cell counting kit 8 (CCK8) and cell migration assays were performed to assess the effects of zerum on MRC-5 cells. Masson's trichrome, Hematoxylin and Eosin (HE), and Sirius Red staining were conducted for pathological evaluation of lung tissue. Western blot experiments were conducted to measure the protein expression levels of Collagen I, α-SMA, Nrf2, and SIRT1. Immunofluorescence and immunohistochemistry assays were used to detect the expression of reactive oxygen species (ROS), Nrf2, and α-SMA. ELISA was employed to measure the levels of MDA, SOD, and GSH-Px. Our findings from in vitro and in vivo studies demonstrated that zerum significantly inhibited the migration ability of TGF-β1-induced MRC-5 cells, reduced ROS production in TGF-β1-induced MRC-5 cells and pulmonary fibrosis mice, and decreased the expression of Collagen I and α-SMA proteins. Additionally, zerum activated the SIRT1/Nrf2 signaling pathway in TGF-β1-induced MRC-5 cells and pulmonary fibrosis mice. Knockdown of SIRT1 abolished the anti-fibrotic effects of zerum. These results suggest that zerum inhibits TGF-β1 and BLM-induced cell and mouse pulmonary fibrosis by activating the SIRT1/Nrf2 pathway., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Idiopathic Pulmonary Fibrosis (IPF), prevalently affecting individuals over 60 years of age, has been mainly studied in young mouse models. The limited efficacy of current treatments underscores the need for animal models that better mimic an aged patient population. We addressed this by inducing pulmonary fibrosis in aged mice, using longitudinal micro-CT imaging as primary readout, with special attention to animal welfare., Methods: A double bleomycin dose was administered to 18-24 months-old male C57Bl/6j mice to induce pulmonary fibrosis. Bleomycin dosage was reduced to as low as 75% compared to that commonly administered to young (8-12 weeks-old) mice, resulting in long-term lung fibrosis without mortality, complying with animal welfare guidelines. After fibrosis induction, animals received Nintedanib once-daily for two weeks and longitudinally monitored by micro-CT, which provided structural and functional biomarkers, followed by post-mortem histological analysis as terminal endpoint., Results: Compared to young mice, aged animals displayed increased volume, reduced tissue density and function, and marked inflammation. This increased vulnerability imposed a bleomycin dosage reduction to the lowest tested level (2.5 µg/mouse), inducing a milder, yet persistent, fibrosis, while preserving animal welfare. Nintedanib treatment reduced fibrotic lesions and improved pulmonary function., Conclusions: Our data identify a downsized bleomycin treatment that allows to achieve the best trade-off between fibrosis induction and animal welfare, a requirement for antifibrotic drug testing in aged lungs. Nintedanib displayed significant efficacy in this lower-severity disease model, suggesting potential patient stratification strategies. Lung pathology was quantitatively assessed by micro-CT, pointing to the value of longitudinal endpoints in clinical trials., (© 2024. The Author(s).)

Recurring lung injury, chronic inflammation, aberrant tissue repair and impaired tissue remodelling contribute to the pathogenesis of pulmonary fibrosis (PF). Neutrophil extracellular traps (NETs) are released by activated neutrophils to trap, immobilise and kill invading pathogen and is facilitated by peptidyl arginine deiminase-4 (PAD-4). Dysregulated NETs release and abnormal PAD-4 activation plays a crucial role in activating pro-fibrotic events in PF. Developmental endothelial locus-1 (Del-1), expressed by the endothelial cells of lungs and brain acts as an endogenous inhibitor of inflammation and fibrosis. We have hypothesised that PAD-4 inhibitor exerts anti-inflammatory and anti-fibrotic effects in mice model of PF. We have also hypothesised by PAD-4 regulated the transcription of Del-1 through co-repression and its inhibition potentiates anti-fibrotic effects of Del-1. In our study, the PAD-4 inhibitor chloro-amidine (CLA) demonstrated anti-NETotic and anti-inflammatory effects in vitro in differentiated HL-60 cells. In a bleomycin-induced PF mice model, CLA administration in two doses (3 mg/kg, I.P and 10 mg/kg, I.P) improved lung function, normalized bronchoalveolar lavage fluid parameters, and attenuated fibrotic events, including markers of extracellular matrix and epithelial-mesenchymal transition. Histological analyses confirmed the restoration of lung architecture and collagen deposition with CLA treatment. ELISA, IHC, IF, RT-PCR, and immunoblot analysis supported the anti-NETotic effects of CLA. Furthermore, BLM-induced PF reduced Del-1 and p53 expression, which was normalized by CLA treatment. These findings suggest that inhibition of PAD-4 results in amelioration of PF in animal model and may involve modulation of Del-1 and p53 pathways, warranting further investigation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Pulmonary fibrosis is a serious interstitial lung disease with no viable treatment except for lung transplantation. Glucagon-like peptide-1 receptor (GLP-1R), commonly regarded as an antidiabetic target, exerts antifibrotic effects on various types of organ fibrosis. However, whether GLP-1R modulates the development and progression of pulmonary fibrosis remains unclear. In this study, we investigated the antifibrotic effect of GLP-1R using in vitro and in vivo models of pulmonary fibrosis., Methods: A silica-induced pulmonary fibrosis mouse model was established to evaluate the protective effects of activating GLP-1R with liraglutide in vivo. Primary cultured lung fibroblasts treated with TGF-β1 combined with IL-1β (TGF-β1 + IL-1β) were used to explore the specific effects of liraglutide, MCC950, and 3PO on fibroblast activation in vitro. Cell metabolism assay was performed to determine the glycolytic rate and mitochondrial respiration. RNA sequencing was utilized to analyse the underlying molecular mechanisms by which liraglutide affects fibroblast activation. ChIP‒qPCR was used to evaluate histone lactylation at the promoters of profibrotic genes in TGF-β1 + IL-1β- or exogenous lactate-stimulated lung fibroblasts., Results: Activating GLP-1R with liraglutide attenuated pulmonary inflammation and fibrosis in mice exposed to silica. Pharmacological inhibition of the NLRP3 inflammasome suppressed PFKFB3-driven glycolysis and vice versa, resulting in decreased lactate production in TGF-β1 + IL-1β-stimulated lung fibroblasts. Activating GLP-1R inhibited TGF-β1 + IL-1β-induced fibroblast activation by disrupting the interaction between the NLRP3 inflammasome and PFKFB3-driven glycolysis and subsequently prevented lactate-mediated histone lactylation to reduce pro-fibrotic gene expression. In addition, activating GLP-1R protected mitochondria against the TGF-β1 + IL-1β-induced increase in oxidative phosphorylation in fibroblasts. In exogenous lactate-treated lung fibroblasts, activating GLP-1R not only repressed NLRP3 inflammasome activation but also alleviated p300-mediated histone lactylation. Finally, GLP-1R activation blocked silica-treated macrophage-conditioned media-induced lung fibroblast activation., Conclusions: The antifibrotic effects of GLP-1R activation on pulmonary fibrosis could be attributed to the inhibition of the interaction between NLRP3 inflammasome and PFKFB3-driven glycolysis, and histone lactylation in lung fibroblasts. Thus, GLP-1R is a specific therapeutic target for the treatment of pulmonary fibrosis., (© 2024. The Author(s).)

Silicosis is an occupational disease caused by exposure to silica characterized by pulmonary inflammation and fibrosis, for which there is a lack of effective drugs. Glycyrrhetinic acid 3-O-β-D-glucuronide (GAMG) can treat silicosis due to its anti-inflammatory and anti-fibrotic properties. Here, the effect of therapeutic interventions of GAMG was evaluated in early-stage and advanced silicosis mouse models. GAMG significantly improved fibrotic pathological changes and collagen deposition in the lungs, alleviated lung inflammation in the BALF, reduced the expression of TNF-α, IL-6, NLRP3, TGF-β1, vimentin, Col-Ⅰ, N-cadherin, and inhibited epithelial-mesenchymal transition (EMT), thereby ameliorating pulmonary fibrosis. Moreover, the dose of 100 mg/kg GAMG can effectively prevent early-stage silicosis, while that of 200 mg/kg was recommended for advanced silicosis. In vitro and in vivo study verified that GAMG can suppress EMT through the NLRP3/TGF-β1/Smad2/3 signaling pathway. Therefore, GAMG could be a promising preventive (early-stage silicosis) and therapeutic (advanced silicosis) strategy, which provides a new idea for formulating prevention and treatment strategies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Idiopathic pulmonary fibrosis (IPF) is a fatal respiratory disease characterized by chronic, progressive scarring of the lung parenchyma, leading to an irreversible decline in lung function. Apart from supportive care, there is currently no specific treatment available to reverse the disease. Based on the fact that tanshinone IIA (TAN) had an effect on protecting against TGF-β1-induced fibrosis through the inhibition of Smad and non-Smad signal pathways to avoid myofibroblasts activation, this study reported the development of the inhalable tanshinone IIA-loaded chitosan-oligosaccharides-coated poly(lactic- co -glycolic acid) (PLGA) nanoparticles (CPN@TAN) for enhancing the pulmonary delivery of tanshinone IIA to treat pulmonary fibrosis. The CPN@TAN with a size of 206.5 nm exhibited excellent in vitro aerosol delivery characteristics, featuring a mass median aerodynamic diameter (MMAD) of 3.967 ± 0.025 μm and a fine particle fraction (FPF) of 70.516 ± 0.929%. Moreover, the nanoparticles showed good stability during atomization and enhanced the mucosal penetration capabilities. The results of confocal spectroscopy confirmed the potential of the nanoparticles as carriers that facilitated the uptake of drugs by NIH3T3, A549, and MH-S cells. Additionally, the nanoparticles demonstrated good in vitro biocompatibility. In a mouse model of bleomycin-induced pulmonary fibrosis, noninvasive inhalation of aerosol CPN@TAN greatly suppressed collagen formation and facilitated re-epithelialization of the destroyed alveolar epithelium without causing systemic toxicity compared with intravenous administration. Consequently, our noninvasive inhalation drug delivery technology based on polymers may represent a promising paradigm and open the door to overcoming the difficulties associated with managing pulmonary fibrosis.

The accumulation of monocyte-derived macrophages in the lung tissue during inflammation is important for the pathogenesis of fibrotic lung disease. Deficiencies in chemokine receptors CCR2 and CCR5 and their ligands, which mediate monocyte/macrophage migration, ameliorate bleomycin (BLM)-induced lung fibrosis. Disulfiram (DSF), which is used to treat alcoholism because of its aldehyde dehydrogenase (ALDH)-inhibiting effect, inhibits monocyte/macrophage migration by inhibiting FROUNT, an intracellular regulator of CCR2/CCR5 signalling. Here, we investigated the antifibrotic effect of oral DSF administration in a mouse model of BLM-induced lung fibrosis, focusing on macrophage response and fibrosis progression. The direct inhibitory activity of DSF on monocyte migration was measured using the Boyden chamber assay and compared with that of DSF-related inhibitors with different FROUNT-inhibition activities. Quantitative PCR was used to determine the expression of fibrosis-promoting genes in the lung tissue. DSF significantly suppressed macrophage infiltration into lung tissues and attenuated BLM-induced lung fibrosis. DSF and its metabolites, diethyldithiocarbamate (DDC) and copper diethyldithiocarbamate (Cu(DDC) 2 ), inhibited monocyte migration toward the culture supernatant of primary mouse lung cells mainly comprising CCL2, whereas cyanamide, another ALDH inhibitor, did not. DSF, with higher inhibitory activity against FROUNT than DDC and Cu(DDC) 2 , inhibited monocyte migration most strongly. In BLM-induced fibrotic lung tissues, profibrotic factors were highly expressed but were reduced by DSF treatment. These results suggest DSF inhibits macrophage infiltration, which might be attributed to its inhibitory effect on FROUNT, and attenuates BLM-induced lung fibrosis. In addition, multiplex immunofluorescence imaging revealed reduced infiltration of S100A4 + macrophages into the lungs in DSF-treated mice and high expression of FROUNT in S100A4 + macrophages in idiopathic pulmonary fibrosis (IPF). These findings underscore the potential of macrophage-targeted therapy with DSF as a promising drug repositioning approach for treating fibrotic lung diseases, including IPF., (© 2024. The Author(s).)

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic and lethal lung disorder for which effective treatments remain limited. Recent investigations revealed a potential link between altered glucose metabolism and the activation of fibroblasts, the key cells responsible for generating and depositing extracellular matrix proteins within the lung interstitium during IPF development., Method: In this study, we aimed to investigate the potential therapeutic impact of albendazole on fibroblast to myofibroblast transition in IPF. We assess albendazole's effectiveness in attenuating the activation of fibroblasts. We focused on elucidating the mechanism underlying albendazole's impact on TGF-β1-induced aerobic glycolysis in both lung tissues and fibroblasts obtained from patients with IPF and other lung fibrosis types. Furthermore, the antifibrotic effects of oral administration of albendazole were investigated in mouse models of pulmonary fibrosis induced by BLM or SiO2. Human precision-cut lung slices were employed to evaluate the impact of albendazole following TGF-β1 stimulation., Result: In this work, we demonstrated that albendazole, a first-line broad-spectrum anthelmintic drug, effectively attenuated fibroblast to myofibroblast transition through alleviating TGF-β1-induced aerobic glycolysis dependent on the LRRN3/PFKFB3 signaling pathway. Additionally, LRRN3 expression was downregulated in both lung tissues and fibroblasts from patients with IPF and other types of lung fibrosis. Importantly, the levels of LRRN3 correlated with the progression of the disease. Notably, oral administration of albendazole exerted potent antifibrotic effects in mouse models of pulmonary fibrosis induced by BLM or SiO2, and in human precision-cut lung slices after TGF-β1 stimulation, as evidenced by improvements in lung morphology, reduced myofibroblast formation, and downregulation of α-SMA, collagen type 1 and Fibronectin expression in the lungs., Conclusion: Our study implies that albendazole can act as a potent agonist of LRRN3 during fibroblast to myofibroblast differentiation and its oral administration shows potential as a viable therapeutic approach for managing IPF., (© 2024. The Author(s).)

Idiopathic pulmonary fibrosis (IPF) is a fatal disease characterized by unpredictable progression and limited therapeutic options. Current diagnosis relies on high resolution computed tomography (HRCT), which may not adequately capture early signs of deterioration. The enzyme autotaxin (ATX) emerges as a prominently expressed extracellular secretory enzyme in the lungs of IPF patients. The objective of this study was to evaluate the effectiveness of 18 F-labeled ATX-targeted tracer [ 18 F]ATX-1905, in comparison with [ 18 F]FDG, for early fibrosis diagnosis, disease evolution monitoring, and treatment efficacy assessment in bleomycin-induced pulmonary fibrosis (BPF) models. To assess treatment efficacy, mice were treated with two commonly used drugs for IPF, pirfenidone or nintedanib, from Day 9 to Day 23 postbleomycin administration. Lung tissue assessments encompassed inflammation severity via H&E staining, and Ashcroft scoring via Masson staining, alongside quantification of ATX expression through ELISA. Positron emission tomography (PET) imaging employing [ 18 F]FDG and [ 18 F]ATX-1905 tracked disease progression pre- and post-treatment. The extent of pulmonary fibrosis corresponded to changes in ATX expression levels in the BPF mouse model. Notably, [ 18 F]ATX-1905 exhibited elevated uptake in BPF lungs during the progression of the disease, particularly evident at the early stage (Day 9). This uptake was inhibited by an ATX inhibitor, PF-8380, underscoring the specificity of the radiotracer. Conversely, [ 18 F]FDG uptake, peaking at Day 15, decreased subsequently, likely reflective of diminished inflammation. A 2-week treatment regimen using either pirfenidone or nintedanib resulted in notable reductions of ATX expression levels and fibrosis degrees within lung tissues, based on ELISA and Masson staining, as evidenced by PET imaging with [ 18 F]ATX-1905. [ 18 F]FDG uptake also decreased following the treatment period. Additionally, PET/CT imaging extended to a nonhuman primate (NHP) BPF model. The uptake of [ 18 F]ATX-1905 (SUV max = 2.2) was significantly higher than that of [ 18 F]FDG (SUV max = 0.7) in fibrotic lung tissue. Using our novel ATX-specific radiotracer [ 18 F]ATX-1905 and PET/CT imaging, we demonstrated excellent ability in early fibrosis detection, disease monitoring, and treatment assessment within lungs of the BPF mouse models. [ 18 F]ATX-1905 displayed remarkable specificity for ATX expression and high sensitivity for ATX alterations, suggesting its potential for monitoring varying ATX expression in lungs of IPF patients.

To evaluate the therapeutic effect and mechanism of rapamycin (RAPA) on pulmonary fibrosis induced by chlormethine in C57BL/6N mice. Based on body weight, the 18-20 g C57BL/6N mice were randomly divided into five groups: control group, chlormethine group, chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, with ten mice in each group. Mice were put to death on the 21st day after the first administration of chlormethine. HE staining and Masson staining were used to observe the pathological changes and degree of fibrosis in the lung tissue of mice, and RT-PCR was used to detect collagen Ⅰ, E-cadherin, vimentin, and α-SMA mRNA expression. After 21 days of administration of chlormethine to mice, significant pulmonary fibrosis characteristics were observed in the lung tissue of the mice. Compared with the chlormethine group, the weight of mice in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, significantly increased ( P <0.05). Compared with the chlormethine group, the expression of pulmonary fibrosis-related indicators (collagen Ⅰ, E-cadherin, vimentin, and α-SMA) significantly improved ( P <0.05) in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group. Compared with the chlormethine group, the pathological changes and collagen deposition in the lung tissue of mice in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, were significantly improved. Transcriptome analysis of the lung tissue of mice revealed that RAPA treatment of chlormethine-induced pulmonary fibrosis might be related to NF-kappa B signaling pathway. Compared with the chlormethine group, the mRNA expression of p65 in the lung tissue of mice in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, significantly decreased ( P <0.01). RAPA has a protective effect on pulmonary fibrosis induced by chlormethine in mice. Its efficacy is comparable to that of dexamethasone, which is currently being used in clinical practice. It is a new alternative therapy, and its mechanism may be related to inhibiting the activation of the NF-kappa B signaling pathway.

Ethnopharmacological Relevance: Pueraria lobata (Willd.) Ohwi is a typical medicinal and edible plant with a long application history in China and Southeast Asia. As a widely used traditional medicine, P. lobata exhibits the properties of anti-inflammatory, antipyretic, antioxidant, relieving cough and asthma. Particularly, the increasing evidence indicates that the P. lobata has the therapeutic effect on fibrotic-related diseases in terms of metabolic regulation. However, the mechanisms of P. lobata on pulmonary fibrosis (PF) has not been thoroughly explored., Aim of the Study: This study aimed to explore the effect of arginine metabolites of P. lobata against PF model by integrating metabolomics and network pharmacology analysis. It might provide a new idea for the target finding of P. lobata anti-pulmonary fibrosis., Materials and Methods: In this study, the Sprague Dawley (SD) rats were randomly divided into five experimental groups: saline-treated control group, bleomycin-induced fibrosis group, prednisolone acetate group, P. lobata 3.2 g/kg group and P. lobata 6.4 g/kg group. The therapeutic effect of P. lobata on bleomycin-induced PF in rats was evaluated by clinical symptoms such as lung function, body weight, hematoxylin eosin staining (HE), Masson staining and hydroxyproline assay. Next, the plasma metabolomics analysis was carried out by LC-MS to explore the pathological differences between the group of control, PF and P. lobata-treated rats. Then, the network pharmacology study coupled with experimental validation was conducted to analysis the results of metabolic research. We constructed the "component-target-disease" network of P. lobata in the treatment of PF. In addition, the molecular docking method was used to verify the interaction between potential active ingredients and core targets of P. lobata. Finally, we tested NOS2 and L-OT in arginine-related metabolic pathway in plasma of the rats by enzyme-linked immunosorbent assay (ELISA). Real-time PCR was performed to observe the level of TNF-α mRNA and MMP9 mRNA. And we tested the expression of TNF-α and MMP9 by Western blot analysis., Results: Our findings revealed that P. lobata improved lung function and ameliorated the pathological symptoms, such as pathological damage, collagen deposition, and body weight loss in PF rats. Otherwise, the plasma metabolomics were employed to screen the differential metabolites of amino acids, lipids, flavonoids, arachidonic acid metabolites, glycoside, etc. Finally, we found that the arginine metabolism signaling mainly involved in the regulating of P. lobata on the treatment of PF rats. Furtherly, the network pharmacology predicted that the arginine metabolism pathway was contained in the top 20 pathways. Next, we integrated metabolomics and network pharmacology that identified NOS2, MMP9 and TNF-α as the P. lobata regulated hub genes by molecular docking. Importantly, it indicated a strong affinity between the puerarin and the NOS2. P. lobata attenuated TNF-α, MMP-9 and NOS2 levels, suppressed TNF-α and MMP-9 protein expression, and decreased L-OT and NOS2 content in PF rats. These results indicated that the effects of P. lobata may ameliorated PF via the arginine metabolism pathway in rats. Therefore, P. lobata may be a potential therapeutic agent to ameliorated PF., Conclusion: In this work, we used metabolomics and network pharmacology to explore the mechanisms of P. lobata in the treatment of PF. Finally, we confirmed that P. lobata alleviated BLM-induced PF in rats by regulating arginine metabolism pathway based on reducing the L-OT and NOS2-related signal molecular. The search for the biomarkers finding of arginine metabolism pathway revealed a new strategy for P. lobata in the treatment of PF., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Purpose: Idiopathic pulmonary fibrosis (IPF) is a fatal progressive condition often requiring lung transplantation. Accelerated senescence of type II alveolar epithelial cells (AECII) plays a crucial role in pulmonary fibrosis progression through the secretion of the senescence-associated secretory phenotype (SASP). Low-dose carbon monoxide (CO) possesses anti-inflammatory, anti-oxidative, and anti-aging properties. This study aims to explore the preventive effects of CO-releasing molecule 2 (CORM2) in a bleomycin-induced pulmonary fibrosis model., Methods: We established an pulmonary fibrosis model in C57BL/6J mice and evaluated the impact of CORM2 on fibrosis pathology using Masson's trichrome staining, fluorescence staining, and pulmonary function tests. Fibrogenic marker expression and SASP secretion in tissues and AECII cells were analyzed using qRT-PCR, Western blot, and ELISA assays both in vivo and in vitro. Additionally, we investigated DNA damage and cellular senescence through immunofluorescence and SA-β-gal staining., Results: CORM2 showed a preventive effect on bleomycin-induced lung fibrosis by improving pulmonary function and reducing the expression of fibrosis-related genes, such as TGF-β, α-SMA, Collagen I/III. CORM2 decreased the DNA damage response by inhibiting γ-H2AX, p53, and p21. We identified PAI-1 as a new target gene that was downregulated by CORM2, and which was associated with cellular senescence and fibrosis. CORM2 effectively inhibited cellular senescence and delayed EMT occurrence in AECII cells., Conclusion: Our study highlights the potential of CORM2 in preventing DNA damage-induced cellular senescence in bleomycin-induced pulmonary fibrosis through modulation of the p53/PAI-1 signaling pathway. These findings underscore the promising prospects of CORM2 in targeting cellular senescence and the p53/PAI-1 pathway as a potential preventive strategy for IPF., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: Acute respiratory distress syndrome (ARDS) patients currently have relatively high mortality, which is associated with early lung fibrosis. This study aimed to investigate whether miR-17 suppression could alleviate ARDS-associated lung fibrosis by regulating Mfn2., Methods: A mouse model of ARDS-related lung fibrosis was constructed via intratracheal instillation of bleomycin. The expression level of miR-17 in lung tissues was detected via quantitative real time polymerase chain reaction (qRT-PCR). In the ARDS mouse model of lung fibrosis, the mitigating effects of miR-17 interference were evaluated via tail vein injection of the miR negative control or the miR-17 antagomir. The pathological changes in the lung tissue were examined via HE staining and Masson's trichrome staining, and the underlying molecular mechanism was investigated via ELISA, qRT-PCR and Western blotting., Results: Bleomycin-induced pulmonary fibrosis significantly increased collagen deposition and the levels of hydroxyproline (HYP) and miR-17. Interfering with miR-17 significantly reduced the levels of HYP and miR-17 and upregulated the expression of Mfn2. The intravenous injection of the miR-17 antagomir alleviated lung inflammation and reduced collagen deposition. In addition, interference with miR-17 could upregulate LC3B expression, downregulate p62 expression, and improve mitochondrial structure., Conclusion: Interfering with miR-17 can improve pulmonary fibrosis in mice by promoting mitochondrial autophagy via Mfn2., (© 2024. Huazhong University of Science and Technology.)

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal fibrotic lung disease. While recent studies have suggested the potential efficacy of tyrosine kinase inhibitors in managing IPF, masitinib, a clinically used tyrosine kinase inhibitor, has not yet been investigated for its efficacy in fibrotic lung diseases. In a previous study on an in vitro neurodegenerative model, we demonstrated the synergistic antitoxic and antioxidant effects of masitinib combined with cromolyn sodium, an FDA-approved mast cell stabilizer. This study aims to investigate the anti-fibrotic and antioxidant effects of the masitinib-cromolyn sodium combination in an in vitro model of pulmonary fibrosis. Fibroblast cell cultures treated with bleomycin and/or hydrogen peroxide (H 2 O 2 ) were subjected to masitinib and/or cromolyn sodium, followed by assessments of cell viability, morphological and apoptotic nuclear changes, triple-immunofluorescence labeling, and total oxidant/antioxidant capacities, besides ratio of Bax and Bcl-2 mRNA expressions as an indication of apoptosis. The combined treatment of masitinib and cromolyn sodium effectively prevented the fibroblast myofibroblast transition, a hallmark of fibrosis, and significantly reduced bleomycin / H 2 O 2 -induced apoptosis and oxidative stress. This study is the first to demonstrate the additive anti-fibrotic, cell-protective, and antioxidant effects of the masitinib-cromolyn sodium combination in an in vitro fibrosis model, suggesting its potential as an innovative therapeutic approach for pulmonary fibrosis. Combination therapy may be more advantageous in that both drugs could be administered in lower doses, exerting less side effects, and at the same time providing diverse mechanisms of action simultaneously., (© 2024 The Author(s). Pharmacology Research & Perspectives published by British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics and John Wiley & Sons Ltd.)

Scope: Titanium dioxide nanoparticles (TiO 2 NPs) are air pollutants that exacerbate chronic respiratory diseases such as asthma and Chronic Obstructive Pulmonary Disease (COPD) However, little is known about the mechanism underlying the antipollutant effects of green tea extract (GTE). This study evaluates the efficacy and mechanism of GTE on lung inflammation and fibrosis in mice exposed to TiO 2 NPs., Methods and Results: The TiO 2 NPs model is induced by having mice inhale TiO 2 NPs, while controls receive an equivalent volume of saline. Treatment with oral GTE is initiated after TiO 2 NPs inhalation and is given once daily for 4 weeks. Airway resistance and pulmonary inflammation are increased in mice exposed to TiO 2 NPs. GTE treatment reduces the airway inflammation and airway resistance, and attenuates the pathological changes including lung fibrosis compared to the mice exposed to TiO 2 NPs. With GTE, there are no significant increases in cytokines and immunoglobulin E (IgE) in mice exposed to TiO 2 NPs. GTE inhibits matrix metalloproteinases (MMPs) and apoptotic factors induced by TiO 2 NPs exposure, and these protective effects of GTE are closely related to the mitogen-activated protein kinase (MAPK) signaling pathway., Conclusion: GTE modulates pulmonary inflammation in mice exposed to air pollutants, suggesting that GTE may be beneficial in respiratory diseases exacerbated by such pollutants., (© 2024 Wiley‐VCH GmbH.)

Background: Pulmonary fibrosis (PF) is a progressive lung disease caused by previous acute lung injury (ALI), but there is currently no satisfactory therapy available. Aerosol inhalation of medicine is an effective way for treating PF. Total ginsenosides (TG) shows potential for the treatment of ALI and PF, but the effects of inhaled TG remain unclear., Purpose: To determine the therapeutic effects of TG in ALI and PF, to assess the superiority of the inhaled form of TG over the routine form, and to clarify the mechanism of action of inhaled TG., Methods: Ultrahigh-performance liquid chromatography coupled with Q-Exactive Orbitrap mass spectrometry (UPLC-QE-MS) was applied to determine the chemoprofile of TG. A mouse model of ALI and PF was established to evaluate the effects of inhaled TG by using bronchoalveolar lavage fluid (BALF) analysis, histopathological observation, hydroxyproline assay, and immunohistochemical analysis. Primary mouse lung fibroblasts (MLF) and human lung fibroblast cell line (HFL1) were applied to determine the in vitro effects and mechanism of TG by using cell viability assay, quantitative real time PCR (qPCR) assay, and western blot (WB) analysis., Results: The UPLC-QE-MS results revealed the main types of ginsenosides in TG, including Re (14.15 ± 0.42%), Rd (8.42 ± 0.49%), Rg1 (6.22 ± 0.42%), Rb3 (3.28 ± 0.01%), Rb2 (3.09 ± 0.00%), Rc (2.33 ± 0.01%), Rg2 (2.09 ± 0.04%), Rb1 (1.43 ± 0.24%), and Rf (0.13 ± 0.06%). Inhaled TG, at dosages of 10, 20, and 30 mg/kg significantly alleviated both ALI and PF in mice. Analyses of BALF and HE staining revealed that TG modulated the levels of IFN-γ, IL-1β, and TGF-β1, reduced inflammatory cell infiltration, and restored the alveolar architecture of the lung tissues. Furthermore, HE and Masson's trichrome staining demonstrated that TG markedly decreased fibroblastic foci and collagen fiber deposition, evidenced by the reduction of blue-stained collagen fibers. Hydroxyproline assay and immunohistochemical analyses indicated that TG significantly decreased hydroxyproline level and down-regulated the expression of Col1a1, Col3a1, and α-sma. The inhaled administration of TG demonstrated enhanced efficacy over the oral route when comparable doses were used. Additionally, inhaled TG showed superior safety and therapeutic profiles compared to pirfenidone, as evidenced by a CCK8 assay, which confirmed that TG concentrations ranging from 20 to 120 μg/ml were non-cytotoxic. qPCR and WB analyses revealed that TG, at concentrations of 25, 50, and 100 μg/ml, significantly suppressed the phosphorylation of smad2 induced by TGF-β1 and down-regulated the expression of fibrotic genes and proteins, including α-sma, Col1a1, Col3a1, and FN1, suggesting an anti-fibrotic mechanism mediated by the smad2 signaling pathway. In vitro, TG's safety and efficacy were also found to be superior to those of pirfenidone., Conclusions: This study demonstrates, for the first time, the therapeutic efficacy of inhaled TG in treating ALI and PF. Inhaled TG effectively inhibits inflammation and reduces collagen deposition, with a particular emphasis on its role in modulating the Smad2 signaling pathway, which is implicated in the anti-fibrotic mechanism of TG. The study also highlights the superiority of inhaled TG over the oral route and its favorable safety profile in comparison to pirfenidone, positioning it as an ideal alternative for ALI and PF therapy., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Background: Pulmonary fibrosis (PF) is a progressive and severe respiratory disease for which there is still a lack of satisfactory treatment methods other than lung transplantation. Evening primrose (EP) is widely used in Chinese folk medicinal herbs, especially for the treatment of lung-related diseases. However, the protective effect of evening primrose against PF has yet to be reported., Purpose: This study explores the pharmacological effect of EP and its possible active components against PF from the perspectives of lung function, histopathological staining, and molecular biology assays., Methods: Establishing a rat pulmonary fibrosis model using bleomycin to detect lung function, pathological changes, and collagen deposition. TGF-β1 was used to establish an in vitro model of PF in BEAS-2B cells, and the active ingredients in evening primrose were screened. Then, the therapeutic effects of 1-Oxohederagenin (C1) and remangilone C (C2) derived from EP were observed in an in vivo model of bleomycin-induced PF, and the differentially expressed genes between the C1 and C2 treatment groups and the model group were screened with transcriptome sequencing. Finally, TGF-β1-induced damage to HFL1 cell was used to explore the specific mechanisms by which C1 and C2 alleviate PF and the involvement of β-catenin signaling., Results: Evening primrose extract showed some ameliorative effects on bleomycin-induced PF in rats, manifested as reduced pathological damage and reduced collagen deposition. The chemical components of C1 and C2 potently ameliorated BLM-induced PF in animals and effectively inhibited fibroblast activation by interfering with β-catenin signaling., Conclusion: Evening primrose extract has certain ameliorative effects on PF. In addation, C1 and C2 might be related with the suppression of fibroblast activation by inhibiting β-catenin signaling., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024 Elsevier GmbH. All rights reserved.)

Background: Nintedanib is used to treat both idiopathic and progressive pulmonary fibrosis (IPF/PPF). Evidence of both an exposure-response relationship and an exposure-toxicity relationship has been found, suggesting the potential value of therapeutic drug monitoring (TDM). We aimed to define the therapeutic window of nintedanib in a real-world cohort., Methods: Data from two clinical studies were pooled for this analysis. To quantify exposure to nintedanib, a population-pharmacokinetic (PK) model was developed. Associations between PK and decline in forced vital capacity (FVC) and diffusing capacity (DLCO) were performed using linear-mixed-effect models (LMEM). The exposure-toxicity relationship was evaluated using a Cox proportional hazards model., Results: In total, 911 PK samples from 99 patients were used to develop the PK model. The LMEM with random slopes and intercepts included 517 pulmonary function tests (PFT) from 81 patients. The average administered nintedanib dose was associated with the rate of FVC decline (p=0.002). Per 50 mg decrease of daily dosage, the rate of FVC decline increased by 53.5 mL/year. Neither nintedanib exposure nor dose significantly affected DLCO decline and they were also not significantly associated with the occurrence of a dose-limiting toxicity (DLT). This may be explained by a large inter- and intrapatient variability in nintedanib PK., Conclusion: Nintedanib dose was significantly associated with FVC loss. However, no significant relationship between nintedanib exposure and the occurrence of DLTs was found in this real-world population, and no therapeutic window could be established. The findings in this study indicate that nintedanib is an unsuitable candidate for performing TDM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Silicosis is a systemic disease with predominantly diffuse fibrosis of the lungs due to prolonged inhalation of free SiO 2 dust during the manufacturing process, for which there is no effective treatment. In this study, we used a combined epigenetic and transcriptomic approach to reveal the chromatin-opening features of silicosis and identify the key transcription factor activator protein 1 (AP-1) that responds to silicosis fibrosis. Therapeutic administration of an AP-1 inhibitor inhibits the PI3K/AKT signaling pathway, reduces fibrosis marker proteins, and significantly ameliorates lung fibrosis in a mouse model of silicosis. In addition, it was observed that the expression of Jun and JunB was significantly up-regulated in a TGF-β1-induced in vitro transdifferentiation model of NIH/3T3 cells, and Co-IP confirmed that a protein complex could be formed between Jun and JunB. Mechanistically, silencing of Jun and JunB expression reversed the activation of the PI3K/AKT signaling pathway and the upregulation of fibrosis marker proteins in NIH/3 T3 cells after TGF-β1 stimulation. Taken together, Jun/JunB is expected to be a potential therapeutic target for silicosis fibrosis., Competing Interests: Declaration of competing interest The authors report no conflicts of interest in this work. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background/objectives: Sepsis-induced acute lung injury (ALI) is the typical complications of sepsis with a high global incidence and mortality. Inhibition of inflammatory response is a crucial and effective strategy for sepsis-induced ALI. Pedunculoside (PE) has been shown to have an anti-inflammatory effect on various diseases. However, the effect and mechanism of PE on sepsis-induced ALI remain unknown., Materials/methods: A mice model of sepsis-induced ALI was constructed by cecal ligation and puncture (CLP). The effect of PE on the CLP-induced mice were assessed using pathological staining, terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL), reverse transcription quantitative polymerase chain reaction (RT-qPCR), enzyme-linked immunosorbent assay (ELISA) and western blot assays., Results: PE reduced pathological symptoms and scores, apoptosis and the W/D ratio of lung tissues in CLP-induced mice. Besides, PE decreased the level of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α), pulmonary fibrosis and the expression of fibrosis markers. Mechanically, PE inhibited AKT/NF-κB signaling in CLP-induced mice. Activation of AKT/NF-κB pathway abolished the ameliorative effect of PE on the pathological symptoms, the release of inflammatory factors and pulmonary fibrosis of CLP-induced mice., Conclusion: PE improved inflammation and pulmonary fibrosis by inhibiting AKT/NF-κB pathway in CLP-induced mice., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Idiopathic pulmonary fibrosis (IPF) is a chronic lung disease that leads to respiratory decline caused by scarring and thickening of lung tissues. Multiple pathways contribute to the fibrotic process in this disease, such as inflammation, epithelial-to-mesenchymal transition, and oxidative stress. The Rho-associated coiled-coil forming protein kinase (ROCK) signaling pathway is a key regulator of profibrotic signaling, as it affects the organization of actin-myosin and the remodeling of the extracellular matrix. ROCK1/2, a downstream effector of RhoA, is overexpressed in patients with IPF and is a promising target for IPF therapy. However, because of the hypotensive side effects of ROCK1/2 inhibitors, selective ROCK2 compounds are being explored. In this study, we report the discovery of GNS-3595, a potent and selective ROCK2 inhibitor that has ∼80-fold selectivity over ROCK1 at physiological concentrations of ATP. GNS-3595 effectively inhibited ROCK2-mediated phosphorylation of myosin light chain and reduced the expression of fibrosis-related proteins (e.g., collagen, fibronectin, and α-smooth muscle actin) in various in vitro cellular models. GNS-3595 also prevented transforming growth factor β-induced fibroblast-to-myofibroblast transition. In addition, in a bleomycin-induced mouse model of pulmonary fibrosis, therapeutic exposure to GNS-3595, suppressed lung fibrosis, stabilized body weight loss, and prevented fibrosis-induced lung weight gain. Transcriptome and protein expression analysis from lung tissues showed that GNS-3595 can revert the fibrosis-related gene expression induced by bleomycin. These results indicate that GNS-3595 is a highly potent, selective, and orally active ROCK2 inhibitor with promising therapeutic efficacy against pulmonary fibrosis.

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.

One of the main efforts of scientists to study drug development is the discovery of novel antiviral agents that could be beneficial in the struggle against viruses that cause diseases in humans. Natural products are complex metabolites that are designed and synthesised by different sources in an attempt to optimise nature. Recently, natural products are still a source of biologically active molecules, facilitating drug discovery. A p21-activating kinase PAK1 is a key regulator of cytoskeletal actin assembly, phenotypic signalling, and transcription process which affects a wide range of cellular processes such as cell motility, invasion, metastasis, cell growth, angiogenesis, and cell cycle progression. Most recently, PAK1 was shown to be involved in the progression of coronavirus-caused pulmonary inflammation (lung fibrosis), but clinical data is not currently available yet. This review highlights the naturally occurring compounds that inhibit the oncogenic, melanogenic, and ageing kinase PAK1. Additionally, the potent anti-inflammatory effects of natural products in an attempt to prevent pulmonary fibrosis in COVID-19 have also been discussed.

Objectives: The impact of anti-fibrotic medications on pulmonary fibrosis caused by COVID-19 remains inconclusive and lacks systematic investigation. This study assessed the efficacy of anti-fibrotic drugs in addressing post-COVID-19 lung fibrosis., Methods: We searched PubMed, Web of Science, Embase, and the Cochrane Library until June 15, 2024. The meta-analysis was performed using Review Manager. Heterogeneity was evaluated utilizing I 2 statistic, and publication bias was assessed via funnel plots., Results: The study (CRD42024552847) included 7 trials with 496 participants. No significant differences were observed in chest CT score (SMD = -0.60, 95% CI: -1.33 to 0.12, P = 0.10), length of hospital stay (MD = -1.34, 95% CI: -4.39 to 1.70, P = 0.39), and mortality (OR = 0.91, 95% CI: 0.50 to 1.64, P = 0.75) between anti-fibrosis and standard treatment groups. Notable improvements in pulmonary function were observed with anti-fibrotic drugs, as indicated by FEV1%pred (MD = 23.95, 95% CI: 12.24 to 35.67, P < 0.0001) and FEV1/FVC (MD = 18.17, 95% CI: 11.96 to 24.38, P < 0.00001)., Conclusions: Anti-fibrotic medications may help reduce fibrotic lesions and improve pulmonary function in post-COVID-19 pulmonary fibrosis, but their practical use is currently based more on theory than on solid medical evidence. Currently, in clinical practice, the use of anti-fibrotic drugs in these patients primarily relies on empirical treatment. Further clinical studies are imperative to bolster its credibility for future applications., Competing Interests: Declarations of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Radiation-induced pulmonary fibrosis (RIPF) is a frequently encountered late complication in patients undergoing radiation therapy, presenting a substantial risk to patient mortality and quality of life. The pathogenesis of RIPF remains unclear, and current treatment options are limited in efficacy. High-dose vitamin C has demonstrated potential when used in conjunction with other adjuvant therapies due to potent anticancer properties. However, the potential relationship between high-dose vitamin C and RIPF has not yet been explored in existing literature. In our study, the RIPF model and the LLC tumor model were used as two animal models to explore how high-dose vitamin C can improve RIPF without hampering the antitumour efficacy of radiotherapy. The impact of high-dose vitamin C on RIPF was assessed through various assays, including micro-CT, HE staining, Masson staining, and immunohistochemistry. Our results indicated that administering high-dose vitamin C 2 days before radiation and continuing for a duration of 6 weeks significantly inhibited the progression of RIPF. In order to explore the mechanism by which high-dose vitamin C attenuates RIPF, we utilized RNA-seq analysis of mouse lung tissue in conjunction with publicly available databases. Our findings indicated that high-dose vitamin C inhibits the differentiation of fibroblasts into myofibroblasts by targeting S100A8 and S100A9 derived from neutrophils. Additionally, the combination of high-dose vitamin C and radiation demonstrated enhanced inhibition of tumor growth in a murine LLC tumor model. These results revealed that the combination of radiotherapy and high-dose vitamin C may offer a promising therapeutic approach for the clinical management of thoracic tumors and the prevention of RIPF., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Two new prenylated flavonol glycosides, namely Desmethylicaritin-3- O - β -D-glucopyranosyl-(1→3)- α -L(4″- O -acetyl) rhamnopyranosyl-7- O - β -D(6''''- O -acetyl)-glucopyranoside ( 1 ) and 5,7,3',4'-tetrahydroxyl-8-(3,3-dimethylallyl)-flavonol-3- O - α -L-rhamnopyranoside ( 2 ), and one with no NMR spectral data reported ( 3 ) were isolated from Epimedium koreanum Nakai. Their structures were elucidated by 1D, 2D NMR and HRESIMS analysis. The identification of the sugar moieties was carried out by means of acid hydrolysis and HPLC analysis of their derivatives. The anti-pulmonary fibrosis activities result showed that compound 2 had significant inhibitory effects on A549 cell fibrosis, which was similar to that of the positive control drug, pirfenidone.

Nobiletin (NOB), a polymethoxylated flavone isolated from citrus peels, is a promising dietary treatment for lung diseases, such as pulmonary fiborsis. In this work, the underlying mechanisms of NOB's preventative effect on pulmonary fibrosis were explored using bleomycin-exposed mice and IL-4-induced M2 polarization of the macrophages. Results showed that NOB treatment could significantly ameliorate lung fibrosis by suppressing pathological damages, collagen deposition, and fibroblat activation. Moreover, NOB obviously reduced the M2 macrophage-related proteins, including CD206, Arg1, and pro-fibrotic mediators such as TGF-β and CTGF, which might contribute to the antifibrosis effect of NOB. Network analysis of the differentially expressed genes in NOB-treated M2 macrophages showed that autophagy, mTOR signaling pathway, and AMPK signaling pathway might be involved in the effects of NOB. Further exploration illustrated that autophagy was enhanced in NOB-treated lung and M2 macrophages.The addition of 3MA, an autophagy inhibitor, could significantly weaken the effect of NOB on lung fibrosis and macrophage M2 polarization. Additionally, NOB also markedly decreased the expression of p-AMPK, p-mTOR, and p-P70S6K in the M2 macrophages and lung tissues of BLM-exposed mice. Compound C, an AMPK agonist, significantly suppressed NOB-induced activation of AMPK and mTOR signals, as well as its inhibitory effect on autophagy, M2 macrophages and lung fibrosis both in vitro and in vivo, supporting the requirement of AMPK-mTOR-mediated autophagy for the NOB's antifibrosis activity. Taken together, this study suggests that NOB ameliorates pulmonary fibrosis likely involving the inhibition of M2 macrophage via activating AMPK-mTOR-mediated autophagy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Background: Nintedanib is a primary antifibrosing medication available for idiopathic pulmonary fibrosis, systemic sclerosis-interstitial lung disease, and progressive pulmonary fibrosis, with scattered report of drug-induced thrombocytopenia., Case Report: A 60-year-old Asian male with no history of thrombocytopenia was administered with nintedanib to treat progressive pulmonary fibrosis. The platelet count dropped rapidly after introduction of nintedanib and resolved gradually by withdrawal of the medication along with thrombopoietin receptor agonist., Conclusion: Based on experience from the limited reports, nintedanib-induced thrombocytopenia is typically reversible and manageable. Close monitoring of platelet counts in patients receiving this medication should be warranted., (© 2024. The Author(s).)

The objective of this study was to employ bioinformatics and network pharmacology methodologies to investigate the targets and molecular mechanisms of remdesivir in the treatment of coronavirus disease 2019 (COVID-19)-associated pulmonary fibrosis (PF). Several open-source databases were utilized to confirm the shared targets of remdesivir, COVID-19, and PF. Following this, a comprehensive analysis incorporating function enrichment, protein-protein interaction (PPI), transcription factor (TF), and molecular docking was conducted to investigate the potential mechanisms underlying the effectiveness of remdesivir in the treatment of COVID-19-associated PF. The initial validation of these findings was performed using publicly available histological and single-cell sequencing databases. The functional enrichment analysis revealed a strong association between remdesivir and viral defense, inflammatory response, and immune response. The key pathways identified in the study were transforming growth factor (TGF-β), PI3K-Akt, mTOR, MAPK, epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor resistance, HIF-1, and Toll-like receptor signaling pathways. Additionally, the PPI analysis demonstrated the network relationships of 13 important targets, while the TF analysis provided valuable insights into the regulatory networks of these targets. Among the identified TFs, RELA was found to be the most significant. To validate our findings, we utilized publicly available histological and single-cell sequencing databases, successfully confirming the involvement of 8 key targets, including AKT1, EGFR, RHOA, MAPK1, PIK3R1, MAPK8, MAPK14, and MTOR. Furthermore, molecular docking studies were conducted to assess the interaction between remdesivir and the identified key targets, thus confirming its effective targeting effects. Remdesivir has the potential to exert antiviral, anti-inflammatory, and immunomodulatory effects in the context of COVID-19-associated PF., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 the Author(s). Published by Wolters Kluwer Health, Inc.)

Objective: A mouse silicosis model was constructed by injecting silicon dioxide (SiO(2)) particles into the trachea to explore the effect and mechanism of Cordyceps cicadae polysaccharides (CCP) on ameliorating pulmonary fibrosis in silicosis mice. Methods: In May 2023, CCP were extracted and isolated, the monosaccharide composition and functional group composition were analyzed by high performance liquid chromatography and Fourier transform infrared spectroscopy. C57BL/6J mice were injected with 50 μl 50 mg/ml SiO(2) suspension to construct silicosis mouse model, which were then randomly divided into model group, CCP intervention groups [low dose group (LCCP group), medium dose group (MCCP group) and high dose group (HCCP group) ], the control group was administered by physiological saline, 8 mice in each group. Mice in the CCP intervention groups received oral gavage administration once daily with CCP solution (100, 200 and 400 mg/kg), while control group and model group received physiological saline, lasted for 30 days. The body weight of mice was recorded and the lung coefficient was calculated. The pathomorphological changes of mouse lung tissue were determined by HE and Masson staining. The contents of fibrosis indexes [hydroxyproline acid (HYP), connective tissue growth factor (CTGF) and matrix metallopeptidase 2 (MMP-2) ] of lung tissue and the pro-inflammatory factors[tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) ] of lung tissue and alveolar lavage fluid were determined by ELISA. The expression level of Collagen Ⅰ was determined by immunohistochemistry. The relative protein expression levels of transforming growth factor-β1 (TGF-β1), P-Smad2, α-smooth muscle actin (α-SMA), Toll-like receptor 4 (TLR4), nuclear factor kappa-B p65 (NF-κBp65) and myeloid differentiation primary response gene 88 (MyD88) in lung tissue were determined by Western blot. Results: The total sugar content of the CCP was 86.78%, composed of D-mannose, D-rhamnose, D-glucose and D-galactose, with a molar ratio of 12.71∶1.53∶1.00∶12.64. The infrared spectrum indicated the characteristic groups of its polysaccharides. Compared with the control group, the body weight of mice in the model group was decreased, lung coefficient was increased, the contents of HYP, CTGF and MMP-2 in lung tissue were increased, and the contents of TNF-α, IL-1β and IL-6 in lung tissue and alveolar lavage fluid were increased ( P <0.05). The mice lung showed massive inflammatory cell infiltration and collagen fiber deposition, and the silicosis fibrosis was severe. The expression of CollagenⅠin lung tissue of model group was increased, and the proteins expression levels of TGF-β1, P-Smad2/Smad2, α-SMA, TLR4, NF-κBp65 and MyD88 were increased in mouse lung tissue ( P <0.05). Compared with the model group, the body weights of mice in the MCCP and HCCP groups were increased, the lung coefficients were decreased, the contents of HYP, CTGF and MMP-2 in lung tissue were decreased, and the contents of TNF-α, IL-1β and IL-6 in lung tissue and alveolar lavage fluid were decreased ( P <0.05). The inflammatory cell infiltration in the lung was reduced, and the degree of fibrosis was improved to varying degrees. The expression level of CollagenⅠwas down-regulated in the lung tissue of MCCP and HCCP groups, and the protein expression levels of TGF-β1, P-Smad2/Smad2, α-SMA, TLR4, NF-κBp65 and MyD88 were decreased in lung tissue ( P <0.05) . Conclusion: The CCP could reduce the levels of fibrosis-related indicators and pro-inflammatory factors in lung tissue, ameliorating mouse lung inflammation and silicosis fibrosis caused by SiO(2) particles by inhibiting the activation of TGF-β1/Smad pathway and TLR4/nuclear factor kappa-B (NF-κB) pathway.

Pulmonary fibrosis is a lethal interstitial lung disease, for which current treatments are inadequate in halting its progression. A significant factor contributing to the development of fibrosis is insufficient autophagy, which leads to increased fibroblast proliferation and collagen deposition. However, treatments aimed at upregulating autophagy often cause further lung pathology due to the disruption of epithelial cell balance. In response, we have developed a novel macrophage delivery system loaded with an epithelial-to-mesenchymal transition inhibitor, hyperoside (HYP), and an autophagy inducer, rapamycin (RAP). This system targets the fibrotic areas of the lung through chemotaxis, releases liposomes via macrophage extracellular traps, and effectively inhibits fibroblast proliferation while restoring the alveolar structure through the combined effects of RAP and HYP, ultimately reducing lung pathology without causing systemic toxicity. Our findings not only highlight a promising method to enhance autophagy-based treatments for pulmonary fibrosis but also demonstrate the potential of macrophages as effective nanocarriers for drug delivery.

Epigallocatechin gallate (EGCG) is a polyphenol plant metabolite abundant in tea that has demonstrated antifibrotic properties in the lung. In this issue of the JCI, Cohen, Brumwell, and colleagues interrogated the mechanistic action of EGCG by investigating lung biopsies of patients with mild interstitial lung disease (ILD) who had undergone EGCG treatment. EGCG targeted the WNT inhibitor SFRP2, which was enriched in fibrotic fibroblasts and acted as a TGF-β target, with paracrine effects leading to pathologic basal metaplasia of alveolar epithelial type 2 cells. This study emphasizes the epithelial-mesenchymal trophic unit as a central signaling hub in lung fibrosis. Understanding and simultaneous targeting of interlinked signaling pathways, such as TGF-β and WNT, paves the road for future treatment options for pulmonary fibrosis.

N-acetylcysteine (NAC) is a commonly used mucolytic agent and antidote for acetaminophen overdose. For pulmonary diseases, NAC exhibits antioxidative properties, regulates cytokine production, reduces apoptosis of lung epithelial cells, and facilitates the resolution of inflammation. However, the efficacy of NAC in clinical trials targeting different pathological conditions is constrained by its short half-life and low bioavailability. In the present study, a series of NAC derivatives were designed and synthesized to further enhance its pharmacological activity. Structure-activity relationship (SAR) studies were conducted to optimize the activating groups. In vitro evaluations revealed that compounds 4 r, 4 t, 4 w, and 4 x exhibited superior antioxidative and anti-inflammatory activities compared to the positive controls of NAC and fudosteine. The ADME prediction analysis indicated that these compounds exhibited a favorable pharmacological profile. In-vivo experiments with compound 4 r demonstrated that the high-dose group (80 mg/kg) exhibited improved therapeutic effects in reversing the HPY level in mice with pulmonary fibrosis compared to the NAC group (500 mg/kg), further proving its superior oral bioavailability and therapeutic effect compared to NAC., (© 2024 Wiley-VCH GmbH.)

Background: Idiopathic pulmonary fibrosis (IPF) is a group of chronic interstitial pulmonary diseases characterized by myofibroblast proliferation and extracellular matrix (ECM) deposition. However, current treatments are not satisfactory. Therefore, more effective therapies need to be explored. Cepharanthine (CEP) is a naturally occurring alkaloid that has recently been reported to have multiple pharmacological effects, particularly in chronic inflammation., Methods: For in vivo experiments, first, a pulmonary fibrosis murine model was generated via tracheal injection of bleomycin (BLM). Second, the clinical manifestations and histopathological changes of the mice were used to verify that treatment with CEP might significantly reduce BLM-induced fibrosis. Furthermore, flow cytometric analysis was used to analyze the changes in the number of M2 macrophages in the lung tissues before and after treatment with CEP to explore the relationship between macrophage M2 polarization and pulmonary fibrosis. In vitro, we constructed two co-culture systems (THP-1 and MRC5 cells, RAW264.7 and NIH 3T3 cells), and measured the expression of fibrosis-related proteins to explore whether CEP could reduce pulmonary fibrosis by regulating macrophage M2 polarization and fibroblast activation., Results: The results showed that the intranasal treatment of CEP significantly attenuated the symptoms of pulmonary fibrosis induced by BLM in a murine model. Our findings also indicated that CEP treatment markedly reduced the expression of fibrosis markers, including TGF-β1, collagen I, fibronectin and α-SMA, in the mouse lung. Furthermore, in vitro studies demonstrated that CEP attenuated pulmonary fibrosis by inhibiting fibroblast activation through modulating macrophage M2 polarization and reducing TGF-β1 expression., Conclusions: This study demonstrated the potential and efficacy of CEP in the treatment of pulmonary fibrosis. In particular, this study revealed a novel mechanism of CEP in inhibiting fibroblast activation by regulating macrophage M2 polarization and reducing the expression of fibrosis-associated factors. Our findings open a new direction for future research into the treatment of pulmonary fibrosis., (© 2024. The Author(s).)

Silicosis is a progressive disease characterized by interstitial fibrosis resulting from inhalation of silica particles, and currently lacks specific treatment. Hydrogen (H 2 ) has demonstrated antioxidative, anti-inflammatory, and anti-fibrotic properties, yet its efficacy in treating silicosis remains unexplored. In this study, rats exposed to silica were administered interventions of H 2 combined with tetrandrine, and euthanized at 14, 28, and 56 days post-intervention. Lung tissues and serum samples were collected for analysis. Histological examination, MDA assay, enzyme-linked immunosorbent assay, hydroxyproline assay, and Western blotting were employed to assess the impact of H 2 combined with tetrandrine on pulmonary fibrosis. The results revealed that this combination significantly alleviated inflammation in silicosis-afflicted rats, effectively suppressed levels of MDA, TNF-α, and IL-1β expression, and inhibited epithelial-mesenchymal transition (EMT), thereby ameliorating pulmonary fibrosis. Notably, protein expression level of E-cadherin was increased，however protein expression levels of vimentin and α-SMA were reduced, and TGF-β were reduced, alongside a significant decrease in hydroxyproline content. Furthermore, H 2 combined with tetrandrine downregulated protein expression of NF-κB p65, NF-κB p-p65, Caspase-1, ASC, and NLRP3. These findings substantiate the hypothesis that H 2 combined with tetrandrine mitigates inflammation associated with silicosis and suppresses the EMT process to ameliorate fibrosis via the NF-κB/NLRP3 signaling pathway. However, the pressure of airway opening was not assessed in this study and dynamic readings of lung physiological function were not obtained, which is a major limitation of this study., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: Harmine has many pharmacological activities and has been found to significantly inhibit the fibrosis of keloid fibroblasts. DNA damage repair (DDR) is essential to prevent fibrosis. This study aimed to investigate the effects of harmine on pulmonary fibrosis and its underlying mechanisms., Methods: Bleomycin and TGF-β1 were used to construct pulmonary fibrosis models in vivo and in vitro, then treated with harmine to explore harmine's effects in treating experimental pulmonary fibrosis and its related mechanisms. Then, RNA sequencing was applied to investigate further the crucial DDR-related genes and drug targets of harmine against pulmonary fibrosis. Finally, the expression levels of DDR-related genes were verified by real-time quantitative PCR (RT-qPCR) and western blot., Results: Our in vivo experiments showed that harmine treatment could improve weight loss and lung function and reduce tissue fibrosis in mice with pulmonary fibrosis. The results confirmed that harmine could inhibit the viability and migration of TGF-β1-induced MRC-5 cells, induce their apoptosis, and suppress the F-actin expression, suggesting that harmine could suppress the phenotypic transition from lung fibroblasts to lung myoblasts. In addition, RNA sequencing identified 1692 differential expressed genes (DEGs), and 10 DDR-related genes were screened as critical DDR-related genes. RT-qPCR and western blotting showed that harmine could down-regulate the expression of CHEK1, ERCC1, ERCC4, POLD1, RAD51, RPA1, TOP1, and TP53, while up-regulate FEN1, H2AX and GADD45α expression., Conclusions: Harmine may inhibit pulmonary fibrosis by regulating DDR-related genes and activating the TP53-Gadd45α pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Pulmonary fibrosis (PF) is an interstitial lung disease characterized by inflammation and fibrotic changes, with an unknown cause. In the early stages of PF, severe inflammation leads to the destruction of lung tissue, followed by upregulation of fibrotic factors like Transforming growth factor-β (TGF-β) and connective tissue growth factor (CTGF), which disrupt normal tissue repair. Geniposide, a natural iridoid glycoside primarily derived from the fruits of Gardenia jasminoides Ellis, possesses various pharmacological activities, including liver protection, choleretic effects, and anti-inflammatory properties. In this study, we investigated the effects of Geniposide on chronic inflammation and fibrosis induced by bleomycin (BLM) in mice with pulmonary fibrosis (PF). PF was induced by intratracheal instillation of bleomycin, and Geniposide(100/50/25mg•kg-1) was orally administered to the mice once a day until euthanasia(14 day/28 day). The Raw264.7 cell inflammation induced by LPS was used to evaluate the effect of Geniposide on the activation of macrophage. Our results demonstrated that Geniposide reduced lung coefficients, decreased the content of Hydroxyproline, and improved pathological changes in lung tissue. It also reduced the number of inflammatory cells and levels of pro-inflammatory cytokines in bronchoalveolar lavage fluid (BALF) of bleomycin-induced PF mice. At the molecular level, Geniposide significantly down-regulated the expression of TGF-β1, Smad2/3, p38, and CTGF in lung tissues of PF mice induced by bleomycin. Molecular docking results revealed that Geniposide exhibited good binding activity with TGF-β1, Smad2, Smad3, and p38. In vitro study showed Geniposide directly inhibited the activation of macrophage induced by LPS. In conclusion, our findings suggest that Geniposide can ameliorate bleomycin-induced pulmonary fibrosis in mice by inhibiting the TGF-β/Smad and p38MAPK signaling pathways., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Yin et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Pulmonary fibrosis (PF) and tissue remodeling can greatly impair pulmonary function and often lead to fatal outcomes., Methodology: In the present study, we explored a novel molecular interplay of long noncoding (Lnc) RNA CBR3-AS1/ miRNA-29/ FIZZ1 axis in moderating the inflammatory processes, immunological responses, and oxidative stress pathways in bleomycin (BLM)-induced lung fibrosis. Furthermore, we investigated the pharmacological potential of Trimetazidine (TMZ) in ameliorating lung fibrosis., Results: Our results revealed that the BLM-treated group exhibited a significant upregulation in the expression of epigenetic regulators, lncRNA CBR3-AS1 and FIZZ1, compared to the control group (P<0.0001), along with the downregulation of miRNA-29 expression. Furthermore, Correlation analysis showed a significant positive association between lnc CBR3-AS1 and FIZZ1 (R=0.7723, p<0.05) and a significant negative association between miRNA-29 and FIZZ1 (R=-0.7535, p<0.05), suggesting lnc CBR3-AS1 as an epigenetic regulator of FIZZ1 in lung fibrosis. BLM treatment significantly increased the expression of Notch, Jagged1, Smad3, TGFB1, and hydroxyproline. Interestingly, the administration of TMZ demonstrated the ability to attenuate the deterioration effects caused by BLM treatment, as indicated by biochemical and histological analyses. Our investigations revealed that the therapeutic potential of TMZ as an antifibrotic drug could be ascribed to its ability to directly target the epigenetic regulators lncRNA CBR3-AS1/ miRNA-29/ FIZZ1, which in turn resulted in the mitigation of lung fibrosis. Histological and immunohistochemical analyses further validated the potential antifibrotic effects of TMZ by mitigating the structural damage associated with fibrosis., Discussion: Taken together, our study showed for the first time the interplay between epigenetic lncRNAs CBR3-AS1 and miRNA-29 in lung fibrosis and demonstrated that FIZZ1 could be a downregulatory gene for lncRNA CBR3-AS1 and miRNA-29. Our key findings demonstrate that TMZ significantly reduces the expression of fibrotic, oxidative stress, immunomodulatory, and inflammatory markers, along with epigenetic regulators associated with lung fibrosis. This validates its potential as an effective antifibrotic agent by targeting the CBR3-AS1/miRNA-29/FIZZ1 axis., Competing Interests: The authors declare that this research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest., (© 2024 Alzahrani et al.)

Peimisine has therapeutic effects on cough, asthma, acute lung injury and liver fibrosis. However, it has not been reported whether peimisine has an inhibitory effect on pulmonary fibrosis. In current study, a mouse pulmonary interstitial fibrosis model was established to investigate the efficacy of peimisine. Mice were categorized into six groups: Control, model, pirfenidone and three peimisine multi-dose groups. After the modelling, each group was given drugs for 21 days. Mice were euthanized and the histopathology changes of the lung were compared. The contents of cytokines in serum were determined. The mRNA expression levels of related genes in the lung tissue were detected. The contents of macrophages and neutrophils in the bronchoalveolar lavage fluid (BALF) were detected. The antifibrotic effect of peimisine was validated by using MRC-5 cells. The results demonstrated that peimisine could alleviate the destruction of alveolar structure and reduce the aggregation of inflammatory cells. Peimisine could reduce the protein expression levels of cytokines in serum. The mRNA levels of related genes were regulated. The contents of macrophages and neutrophils were decreased. Peimisine had a regulatory effect on the abnormal proliferation of MRC-5 cells. The mechanism was related to regulating extra cellular matrix (ECM) and epithelial-mesenchymal transition (EMT).

Pulmonary fibrosis (PF) is a horrible lung disease that causes pulmonary ventilation dysfunction and respiratory failure, severely impacting sufferers' physical and mental health. Existing drugs can only partially control the condition and are prone to toxic side effects. Anti-inflammatory treatment is the committed step to alleviate PF. Celastrol (CLT) has significant anti-inflammatory effects and can reverse M1-type transformation of macrophages. In this study, we have developed liposomes loaded with CLT, modified with folate (FA), designated FA-CLT-Lips, which facilitate drug delivery by targeting macrophages. FA-CLT-Lips were shown to be more readily absorbed by macrophages in vitro and to encourage the transition of M1 macrophages into M2 macrophages. In addition, FA-CLT-Lips can inhibit the phosphorylation of Smad2/3, effectively reducing the deposition of extracellular matrix (ECM) and the production of inflammatory factors. This showed that FA-CLT-Lips can ameliorate early lung fibrosis by lowering inflammation. In vivo studies have shown that FA-CLT-Lips accumulate in lung tissue to better attenuate lung injury and collagen deposition, with less toxicity compared to free CLT. In summary, FA receptor-targeting liposomes loaded with CLT provide a secure and reliable PF therapy., (© 2024. Controlled Release Society.)

Pulmonary toxicity is a serious side effect of some specific anticancer drugs. Bleomycin is a well-known anticancer drug that triggers severe reactions in the lungs. It is an approved drug that may be prescribed for the treatment of testicular cancers, Hodgkin's and non-Hodgkin's lymphomas, ovarian cancer, head and neck cancers, and cervical cancer. A large number of experimental studies and clinical findings show that bleomycin can concentrate in lung tissue, leading to massive oxidative stress, alveolar epithelial cell death, the proliferation of fibroblasts, and finally the infiltration of immune cells. Chronic release of pro-inflammatory and pro-fibrotic molecules by immune cells and fibroblasts leads to pneumonitis and fibrosis. Both fibrosis and pneumonitis are serious concerns for patients who receive bleomycin and may lead to death. Therefore, the management of lung toxicity following cancer therapy with bleomycin is a critical issue. This review explains the cellular and molecular mechanisms of pulmonary injury following treatment with bleomycin. Furthermore, we review therapeutic targets and possible promising strategies for ameliorating bleomycin-induced lung injury., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Silicosis is an occupational disease of the lungs brought in by repeated silica dust exposures. Inhalation of crystalline silica leads to persistent lung inflammation characterized by lung lesions due to granuloma formation. The specific molecular mechanism has not yet been identified, though. The Present study investigated the impact of silica-exposed lung fibrosis and probable molecular mechanisms. Here, Curcumin, derived from Curcuma longa shown to be an effective anti-inflammatory and anti-fibrotic molecule has been taken to investigate its therapeutic efficacy in silica-induced lung fibrosis. An experimental model of silicosis was established in mice where curcumin was administered an hour before intranasal silica exposure every alternate day for 35 days. Intranasal Curcumin treatment reduced silica-induced oxidative stress, inflammation marked by inflammatory cell recruitment, and prominent granuloma nodules along with aberrant collagen repair. Its protective benefits were confirmed by reduced MMP9 activities along with EMT markers (Vimentin and α-SMA). It has restored autophagy and suppressed the deposition of damaged mitochondria after silica exposure. Intranasal Curcumin also inhibited oxidative stress by boosting antioxidant enzyme activities and enhanced Nrf2-Keap1 expressions. Higher levels of PINK1, PARKIN, Cyt-c, P62/SQSTM, and damaged mitochondria in the silicosis group were significantly lowered after curcumin and dexamethasone treatments. Curcumin-induced autophagy resulted in reduced silica-induced mitochondria-dependent apoptosis. We report that intranasal curcumin treatment showed protective properties on pathological features prompted by silica particles, suggesting that the compound may constitute a promising strategy for the treatment of silicosis in the near future., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Idiopathic pulmonary fibrosis is a progressive lung disease characterized by excessive extracellular matrix accumulation and myofibroblast proliferation with limited treatment options available. M2 macrophages are pivotal in pulmonary fibrosis, where they induce the epithelial-to-mesenchymal and fibroblast-to-myofibroblast transitions. In this study, we evaluated whether MEL-dKLA, a hybrid peptide that can eliminate M2 macrophages, could attenuate pulmonary fibrosis in a cell co-culture system and in a bleomycin-induced mouse model. Our findings demonstrated that the removal of M2 macrophages using MEL-dKLA stimulated reprogramming to an antifibrotic environment, which effectively suppressed epithelial-to-mesenchymal and fibroblast-to-myofibroblast transition responses in lung epithelial and fibroblast cells and reduced extracellular matrix accumulation both in vivo and in vitro. Moreover, MEL-dKLA exhibited antifibrotic efficacy without damaging tissue-resident macrophages in the bleomycin-induced mouse model. Collectively, our findings suggest that MEL-dKLA may be a new therapeutic option for the treatment of idiopathic pulmonary fibrosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Background: The efficacy of flavonoid supplementation in animal models of pulmonary fibrosis has been demonstrated., Purpose: We conducted a systematic review and meta-analysis to evaluate the efficacy and underlying mechanisms of flavonoids in animal models of bleomycin-induced pulmonary fibrosis., Study Design: Relevant studies (n = 45) were identified from English- and Chinese-language databases from the inception of the database until October 2023., Methods: Methodological quality was evaluated using the SYRCLE risk of bias tool. Statistical analyses were conducted using RevMan 5.3 and Stata 17.0. Lung inflammation and fibrosis score were the primary outcome indicators., Results: Flavonoids can alleviate pathological changes in the lungs. The beneficial effects of flavonoids on pulmonary fibrosis likely relate to their inhibition of inflammatory responses, restoration of oxidative and antioxidant homeostasis, and regulation of fibroblast proliferation, migration, and activation by transforming growth factor β1/mothers against the decapentaplegic homologue/AMP-activated protein kinase (TGF-β1/Smad3/AMPK), inhibitor kappa B alpha/nuclear factor-kappa B (IκBα/NF-κB), phosphatidylinositol 3-kinase (PI3K)/AKT, interleukin 6/signal transducer/activator of transcription 3 (IL6/STAT3), and nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2-Keap1) pathways., Conclusion: Flavonoids are potential candidate compounds for the prevention and treatment of pulmonary fibrosis. However, extensive preclinical research is necessary to confirm the antifibrotic properties of natural flavonoids., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Pulmonary fibrosis is a fatal and chronic lung disease that is characterized by accumulation of thickened scar in the lungs and impairment of gas exchange. The cases with unknown etiology are referred as idiopathic pulmonary fibrosis (IPF). There are currently no effective therapeutics to cure the disease; thus, the investigation of the pathogenesis of IPF is of great importance. Recent studies on bone morphogenic proteins (BMPs) and their receptors have indicated that reduction of BMP signaling in lungs may play a significant role in the development of lung fibrosis. BMPs are members of TGF-β superfamily, and they have been shown to play an anti-fibrotic role in combating TGF-β-mediated pathways. The impact of BMP receptors, in particular BMPR2, on pulmonary fibrosis is growing attraction to researchers. Previous studies on BMPR2 have often focused on pulmonary arterial hypertension (PAH). Given the strong clinical association between PAH and lung fibrosis, understanding BMPs/BMPR2-mediated signaling pathway is important for development of therapeutic strategies to treat IPF. In this review, we comprehensively review recent studies regarding the biological functions of BMPs and their receptors in lungs, especially focusing on their roles in the pathogenesis of pulmonary fibrosis and fibrosis resolution., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with an unknown underlying cause. There is no complete cure for IPF; however, two anti-fibrotic agents (Nintedanib and pirfenidone) are approved by the USFDA to extend the patient's life span. Therefore, alternative therapies supporting the survival of fibrotic patients have been studied in recent literature. The abundance of phenolic compounds, particularly flavonoids, has gathered attention due to their potential health benefits. Various flavonoids, like naringin, quercetin, baicalin, baicalein, puerarin, silymarin, and kaempferol, exhibit anti-inflammatory and anti-oxidant properties, which help decrease lung fibrosis. Various databases, including PubMed, EBSCO, ProQuest, and Scopus, as well as particular websites, such as the World Health Organisation and the National Institutes of Health, were used to conduct a literature search. Several mechanisms of action of flavonoids are reported with the help of in vivo and cell line studies emphasizing their ability to modulate oxidative stress, inflammation, and fibrotic processes in the lungs. They are reported for the restoration of biomarkers like hydroxyproline, cytokines, superoxide dismutase, malondialdehyde and others associated with IPF and for modulating various pathways responsible for the progression of pulmonary fibrosis. Yet, flavonoids have some drawbacks, such as poor solubility, challenging drug loading, stability issues, and scarce bioavailability. Therefore, novel formulations of flavonoids are explored, including liposomes, solid lipid microparticles, polymeric nanoparticles, nanogels, and nanocrystals, to enhance the therapeutic efficacy of flavonoids in pulmonary fibrosis. This review focuses on the role of flavonoids in mitigating idiopathic pulmonary fibrosis, their mode of action and novel formulations., (© 2024 John Wiley & Sons Ltd.)