A Lung-Targeted Carrier of Carbon Monoxide for Idiopathic Pulmonary Fibrosis Therapy.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive respiratory disease. Arguably, the complex interplay between immune cell subsets, coupled with an incomplete understanding of disease pathophysiology, has hindered the development of successful therapies. Despite efforts to understand its pathophysiology and develop effective treatments, IPF remains a fatal disease, necessitating the exploration of new treatment options. Mesenchymal stromal/stem cell (MSC) therapy has shown promise in experimental models of IPF, but further investigation is needed to understand its therapeutic effect. This study aimed to assess the therapeutic effect of adipose-derived mesenchymal stem cells in a bleomycin-induced pulmonary fibrosis model. First, MSC cells were obtained from mice and characterized using flow cytometry and cell differentiation culture methods. Then adult C57BL/6 mice were exposed to endotracheal instillation of bleomycin and concurrently treated with MSCs for reversal models on day 14. Experimental groups were evaluated on days 14, 21, or 28. Additionally, lung fibroblasts challenged with TGF-β1 were treated with MSCs supernatant or MSCs to explore the mechanisms underlying of pulmonary fibrosis reversal. Mesenchymal stem cells were successfully isolated from mouse adipose tissue and characterized based on their differentiation ability and cell phenotype. The presence of MSCs or their supernatant stimulated the proliferation and migration of lung fibrotic cells. MSCs supernatant reduced lung collagen deposition, improved the Ashcroft score and reduced the gene and protein expression of lung fibrosis-related substances. Bleomycin-challenged mice exhibited severe septal thickening and prominent fibrosis, which was effectively reversed by MSCs treatment. MSC supernatant could suppress the TGF-β1/Smad signaling pathway and supernatant promotes fibroblast autophagy. In summary, this study demonstrates that MSCs supernatant treatment is as effective as MSCs in revert the core features of bleomycin-induced pulmonary fibrosis. The current study has demonstrated that MSCs supernatant alleviates the BLM-induced pulmonary fibrosis in vivo. In vitro experiments further reveal that MSC supernatant could suppress the TGF-β1/Smad signaling pathway to inhibit the TGF-β1-induced fibroblast activation, and promotes fibroblast autophagy by Regulating p62 expression. These findings contribute to the growing body of evidence supporting the therapeutic application of MSCs in cell therapy medicine for IPF.

Heat shock protein 70 protects against bleomycin-induced pulmonary fibrosis in mice

Idiopathic pulmonary fibrosis (IPF) is a deadly interstitial disease that leads to scarring and fibrosis of the lung tissue. In pulmonary fibrosis, there is injury and denudation of the alveolar...

Idiopathic pulmonary fibrosis (IPF) is a chronic devastating disease with poor prognosis. Multiple pathological processes, including inflammation, epithelial mesenchymal transition (EMT), apoptosis, and oxidative stress, are involved in the pathogenesis of IPF. Recent findings suggested that nuclear factor-κB (NF-κB) is constitutively activated in IPF and acts as a central regulator in the pathogenesis of IPF. The aim of our study was to reveal the value of andrographolide on bleomycin-induced inflammation and fibrosis in mice. The indicated dosages of andrographolide were administered in mice with bleomycin-induced pulmonary fibrosis. On day 21, cell counts of total cells, macrophages, neutrophils and lymphocytes, alone with TNF-α in bronchoalveolar lavage fluid (BALF) were measured. HE staining and Masson’s trichrome (MT) staining were used to observe the histological alterations of lungs. The Ashcroft score and hydroxyproline content of lungs were also measured. TGF-β1 and α-SMA mRNA and protein were analyzed. Activation of NF-κB was determined by western blotting and electrophoretic mobility shift assay (EMSA). On day 21 after bleomycin stimulation, andrographolide dose-dependently inhibited the inflammatory cells and TNF-α in BALF. Meanwhile, our data demonstrated that the Ashcroft score and hydroxyproline content of the bleomycin-stimulated lung were reduced by andrographolide administration. Furthermore, andrographloide suppressed TGF-β1 and α-SMA mRNA and protein expression in bleomycin-induced pulmonary fibrosis. Meanwhile, andrographolide significantly dose-dependently inhibited the ratio of phospho-NF-κB p65/total NF-κB p65 and NF-κB p65 DNA binding activities. Our findings indicate that andrographolide compromised bleomycin-induced pulmonary inflammation and fibrosis possibly through inactivation of NF-κB. Andrographolide holds promise as a novel drug to treat the devastating disease of pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive interstitial lung disease characterized by excessive extracellular matrix deposition. No effective treatments are currently available for IPF. High-temperature requirement A3 (HtrA3) suppresses tumor development by antagonizing transforming growth factor β (TGF-β) signaling; however, little is known about the role of HtrA3 in IPF. This study investigated the role of HtrA3 in IPF and underlying mechanisms. Lung tissues were collected from patients with IPF and mice with bleomycin (BLM)-induced pulmonary fibrosis, and HtrA3 expression was measured in tissue samples. Then, HtrA3 gene knockout mice were treated with BLM to induce pulmonary fibrosis and explore the effects and underlying mechanism of HtrA3 on pulmonary fibrosis. HtrA3 was up-regulated in the lung tissues of patients with IPF and the pulmonary fibrotic mouse model compared to corresponding control groups. HtrA3 knockout decreased pulmonary fibrosis-related protein expression, alleviated the symptoms of pulmonary fibrosis, and inhibited epithelial-mesenchymal transition (EMT) in BLM-induced lung tissue compared with BLM-induced wild-type mice. The TGF-β1/Smad signaling pathway was activated in fibrotic lung tissue, whereas HtrA3 knockout inhibited this pathway. The expression level of HtrA3 is increased in fibrotic lungs. HtrA3 knockout alleviates the symptoms of pulmonary fibrosis probably via the TGF-β1/Smad signaling pathway. Therefore, HtrA3 inhibition is a potential therapeutic target for pulmonary fibrosis.

idiopathic pulmonary fibrosis (IPF) is a chronic and progressive lung disease, associated with high mortality rates and unresponsive to currently available treatments. Animal models are critical to identify and validate new therapeutic drug targets, a concept that is nicely highlighted by the review

Objective To investigate the effect of a high dose of N-acetylcystine on pulmonary fibrosis and oxidative stress in patients with idiopathic pulmonary fibrosis. Methods 68 patients with idiopathic pulmonary fibrosis treated at our hospital from May, 2016 to May, 2018 were randomly divided into a control group (n=34) and an observation group (n=34). The control group was treated with a low dose of N-acetylcystein, and the observation group a high dose. The indicators of pulmonary fibrosis and oxidative stress, cytokines, and adverse reactions were compared between the two groups. Results After the treatment, the levels of type Ⅲ and Ⅳ collagens, hyaluronic acid, malondialdehyde, transforming growth factor-β, vascular cell adhesion molecule-1, and IL-13 were lower and the levels of superoxide dismutase and glutathione were higher in the observation group than in the control group [(69.17±7.84) ng/ml vs. (84.16±8.38) ng/ml, (89.73±11.67) ng/ml vs. (106.42±10.81) ng/ml, (87.92±22.67) ng/ml vs. (110.07±21.76) ng/ml, (9.75±1.36) nmol/L vs. (13.24±1.79) nmol/L, (102.54±13.51) pg/ml vs. (121.78±14.13) pg/ml, (311.14±12.91) pg/ml vs. (320.16±13.28) pg/ml, (13.91±1.73) ng/L vs. (17.65±1.42) ng/L, (81.97±6.01) IU/L vs. (72.13±5.76) IU/L, and (46.85±6.94) μmol/L vs. (34.63±7.29) μmol/L; all P 0.05). Conclusion A high dose of N-B-cysteine for patients with idiopathic pulmonary fibrosis can effectively improve the pulmonary fibrosis and the level of oxidative stress, reduce the levels of cytokines, and contribute to the prognosis. Key words: Idiopathic pulmonary interstitial fibrosis; N-acetylcysteine; Pulmonary fibrosis; Oxidative stress; Cytokines

Aberrant proliferation and activation of lung fibroblasts contribute to the initiation and progression of idiopathic pulmonary fibrosis (IPF). However, the mechanisms responsible for the proliferation and activation of fibroblasts are not fully understood. The objective of this study was to investigate the role of miR-101 in the proliferation and activation of lung fibroblasts. miR-101 expression was determined in lung tissues from patients with IPF and mice with bleomycin-induced pulmonary fibrosis. The regulation of miR-101 and cellular signaling was investigated in pulmonary fibroblasts in vitro The role of miR-101 in pulmonary fibrosis in vivo was studied using adenovirus-mediated gene transfer in mice. The expression of miR-101 was down-regulated in fibrotic lungs from patients with IPF and bleomycin-treated mice. The down-regulation of miR-101 occurred via the E26 transformation-specific (ETS) transcription factor. miR-101 suppressed the WNT5a-induced proliferation of lung fibroblasts by inhibiting NFATc2 signaling via targeting Frizzled receptor 4/6 and the TGF-β-induced activation of lung fibroblasts by inhibition of SMAD2/3 signaling via targeting the TGF-β receptor 1. Adenovirus-mediated miR-101 gene transfer in the mouse lung attenuated bleomycin-induced lung fibrosis and improved lung function. Our data suggest that miR-101 is an anti-fibrotic microRNA and a potential therapeutic target for pulmonary fibrosis.

VISTA (V domain immunoglobulin suppressor of T cell activation, also called PD-1H [programmed death-1 homolog]), a novel immune regulator expressed on myeloid and T lymphocyte lineages, is upregulated in mouse and human idiopathic pulmonary fibrosis (IPF). However, the significance of VISTA and its therapeutic potential in regulating IPF has yet to be defined. To determine the role of VISTA and its therapeutic potential in IPF, the expression profile of VISTA was evaluated from human single-cell RNA sequencing data (IPF Cell Atlas). Inflammatory response and lung fibrosis were assessed in bleomycin-induced experimental pulmonary fibrosis models in VISTA-deficient mice compared with wild-type littermates. In addition, these outcomes were evaluated after VISTA agonistic antibody treatment in the wild-type pulmonary fibrosis mice. VISTA expression was increased in lung tissue-infiltrating monocytes of patients with IPF. VISTA was induced in the myeloid population, mainly circulating monocyte-derived macrophages, during bleomycin-induced pulmonary fibrosis. Genetic ablation of VISTA drastically promoted pulmonary fibrosis, and bleomycin-induced fibroblast activation was dependent on the interaction between VISTA-expressing myeloid cells and fibroblasts. Treatment with VISTA agonistic antibody reduced fibrotic phenotypes accompanied by the suppression of lung innate immune and fibrotic mediators. In conclusion, these results suggest that VISTA upregulation in pulmonary fibrosis may be a compensatory mechanism to limit inflammation and fibrosis, and stimulation of VISTA signaling using VISTA agonists effectively limits the fibrotic innate immune landscape and consequent tissue fibrosis. Further studies are warranted to test VISTA as a novel therapeutic target for the IPF treatment.

Idiopathic pulmonary fibrosis (IPF) is a serious progressive and irreversible lung disease with unknown etiology and few treatment options. This disease was once thought to be a chronic inflammatory-driven process, but it is increasingly recognized that the epithelial–mesenchymal transition (EMT) contributes to the cellular origin of fibroblast accumulation in response to injury. During the pathogenesis of pulmonary fibrotic diseases, transforming growth factor-β (TGF-β) signaling is considered a pivotal inducer of EMT and fibroblast activation, and a number of therapeutic interventions that interfere with TGF-β signaling have been developed to reverse established fibrosis. However, efficient and well-tolerated antifibrotic agents are not currently available. Previously, we reported the identification of sorafenib to antagonize TGF-β signaling in mouse hepatocytes in vitro. In this manuscript, we continued to evaluate the antifibrotic effects of sorafenib on bleomycin (BLM)-induced pulmonary fibrosis in mice. We further demonstrated that sorafenib not only profoundly inhibited TGF-β1-induced EMT in alveolar epithelial cells, but also simultaneously reduced the proliferation and collagen synthesis in fibroblasts. Additionally, we presented in vivo evidence that sorafenib inhibited the symptoms of BLM-mediated EMT and fibroblast activation in mice, warranting the therapeutic potential of this drug for patients with IPF.

Inhibition of mTOR ameliorates bleomycin-induced pulmonary fibrosis by regulating epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) has been considered to be involved in organ fibrogenesis. However, there is few direct evidence of this process in the pathophysiology of pulmonary fibrosis in vivo. Therefore, we tried to verify the involvement of this process in the development of pulmonary fibrosis. Since the co-expressions of epithelial and mesenchymal markers are thought to be a marker of EMT, we performed dual-immuunohistochemistry to assess the co-expressions of these proteins in lung tissues from bleomycin-induced pulmonary fibrosis in mice, and from patients with idiopathic pulmonary fibrosis, and nonspecific interstitial pneumonia. Double positive cells for epithelial markers including E-cadherin, T1alpha, or aquaporin 5, and a mesenchymal markers alpha-smooth muscle actin or vimentin were not found in bleomycin-induced pulmonary fibrosis in mice. Double positive cells for E-cadherin, ICAM-1, LEA, CD44v9, or SP-A and alpha-smooth muscle actin or vimentin were not found in lung tissues from normal lung parenchyma, idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia. These results offer at least two possibilities. One is that EMT does not occur in IPF or bleomycin-induced pulmonary fibrosis in mice. Another is that EMT may occur in pulmonary fibrosis but the time during this transition in which cells express detectable levels of epithelial and mesenchymal markers is too small to be detected by double immunohistochemistry.

Idiopathic pulmonary fibrosis (IPF) is an irreversible and progressive interstitial lung disease that results from excessive tissue repair. Production of excessive extracellular matrix (ECM) by myofibroblasts has been known as an important pathological feature in IPF. Connective tissue growth factor (CTGF) is a secreted matricellular protein modulating myofibroblast activation and ECM deposition, leading to fibrosis and tissue remodeling. Protocatechuic acid is extensively distributed in many edible nuts, vegetables, and fruits and is readily absorbed by both animals and humans. Numerous biological actions of protocatechuic acid (PCA) have been observed, including antibacterial, antidiabetic, antioxidant, and anti-inflammatory characteristics. The purpose of this study is to investigate the protective effect of PCA on bleomycin-induced pulmonary fibrosis in rats. The pathological changes of the lung and levels of malondialdehyde (MDA) and glutathione (GSH) were measured. Our results revealed that PCA decreased the oxidative production of lipid MDA and increased GSH content. Moreover, PCA suppressed the expression of inflammatory biomarkers transforming growth factor β (TGF-β) and tumor necrosis factor α (TNF-α), as well as decreased collagen deposition and ECM markers alpha-smooth muscle actin (α-SMA), matrix metalloproteinase-2 (MMP-2), and metallopeptidase inhibitor 1 (TIMP-1). PCA has an anti-fibrotic effect against pulmonary fibrosis by downregulation of the CTGF/NOX4/ET-1 gene expression. Also, PCA treatment ameliorated BLM-induced lung damage by improving alveolar sac structure, reducing inflammatory cell infiltration, and preserving bronchiolar epithelial integrity, suggesting that PCA may serve as a potential treatment option for PF.

Background: The entity of idiopathic pulmonary upper lobe fibrosis (IPUF) was first described in Japan before the disease entity of pleuroparenchymal fibroelastosis (PPFE) was reported［1］. It is now recognized that IPUF and PPFE are similar entities. No reports have compared clinical characteristics of these disease entity and idiopathic pulmonary fibrosis (IPF). Methods: Fifteen patients with IPUF, and 61 patients with idiopathic pulmonary fibrosis (IPF) were retrospectively enrolled. Baseline clinical characteristics, erector spinae muscles assessed by computed tomography (CT)［2］, and prognosis were compared. Furthermore, Cox proportional hazards analyses were performed in both group. Results: Body mass index was significantly lower in IPUF than in IPF (P Conclusions: IPUF have the characteristics of leanness, but may have much muscle mass, compared with IPF. The prognosis of IPF was poorer as compared with that of IPUF. In the IPUF group, lower erector spinae muscles mass by CT was a prognostic factor.

Entrectinib ameliorates bleomycin-induced pulmonary fibrosis in mice by inhibiting TGF-β1 signaling pathway.