Activity In Pulmonary Fibrosis Research Articles

Dynamic changes in autophagy activity in different degrees of pulmonary fibrosis in mice.

The aim of this study is to observe the changes in autophagy activities in lung tissues of mice with different degrees of pulmonary fibrosis (PF), and explore the association between PF and autophagy activity. The PF model was established by bleomycin (BLM, 25 and 35 mg/kg) atomization inhalation in C57BL/6 mice, samples were collected on the 7, 14, and 28 days after BLM administration. Hematoxylin-eosin staining was used to observe the pathological changes in lung tissues. Masson staining was utilized to assess areas of blue collagen fiber deposition in lung tissues. Quantitative real time polymerase chain reaction was used to detect the mRNA expressions of autophagy-related genes, including Atg5, Atg7, and Atg10 in lung tissues. Western blot was used to detect the protein expressions of autophagy-related genes, including p62 and LC3II/LC3I in lung tissues. Compared with control group, BLM dose-dependently decreased PaO2, mRNA expressions of Atg5, Atg7, Atg10, and LC3II/LC3I, while increased lung wet weight, lung coefficient, PF score, the blue area of collagen fibers, and p62 protein on the 7th, 14th, and 28th days. In conclusion, the more severe the PF induced by BLM, the lower the autophagy activity.

The Peptide DHα-(4-pentenyl)-ANPQIR-NH2 Exhibits Antifibrotic Activity in Multiple Pulmonary Fibrosis Models Induced by Particulate and Soluble Chemical Fibrogenic Agents.

Interstitial lung diseases (ILDs) are a group of restrictive lung diseases characterized by interstitial inflammation and pulmonary fibrosis. The incidence of ILDs associated with exposure to multiple hazards such as inhaled particles, fibers, and ingested soluble chemicals is increasing yearly, and there are no ideal drugs currently available. Our previous research showed that the novel and low-toxicity peptide DHα-(4-pentenyl)-ANPQIR-NH2 (DR3penA) had a strong antifibrotic effect on a bleomycin-induced murine model. Based on the druggability of DR3penA, we sought to investigate its effects on respirable particulate silicon dioxide (SiO2)- and soluble chemical paraquat (PQ)-induced pulmonary fibrosis in this study by using western blot, quantitative reverse-transcription polymerase chain reaction (RT-qPCR), immunofluorescence, H&E and Masson staining, immunohistochemistry, and serum biochemical assays. The results showed that DR3penA alleviated the extent of fibrosis by inhibiting the expression of fibronectin and collagen I and suppressed oxidative stress and epithelial-mesenchymal transition (EMT) in vitro and in vivo. Further study revealed that DR3penA may mitigate pulmonary fibrosis by negatively regulating the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathway and mitogen-activated protein kinase (MAPK) pathway. Unexpectedly, through the conversion of drug bioavailability under different routes of administration, DR3penA exerted antifibrotic effects equivalent to those of the positive control drug pirfenidone (PFD) at lower doses. In summary, DR3penA may be a promising lead compound for various fibrotic ILDs. SIGNIFICANCE STATEMENT: Our study verified that DHα-(4-pentenyl)-ANPQIR-NH2 (DR3penA) exhibited positive antifibrotic activity in pulmonary fibrosis induced by silicon dioxide (SiO2) particles and soluble chemical paraquat (PQ) and demonstrated a low-dose advantage compared to the small-molecule drug pirfenidone (PFD). The peptide DR3penA can be further developed for the treatment of multiple fibrotic lung diseases.

Lung extracellular matrix modulates KRT5+ basal cell activity in pulmonary fibrosis

Aberrant expansion of KRT5+ basal cells in the distal lung accompanies progressive alveolar epithelial cell loss and tissue remodelling during fibrogenesis in idiopathic pulmonary fibrosis (IPF). The mechanisms determining activity of KRT5+ cells in IPF have not been delineated. Here, we reveal a potential mechanism by which KRT5+ cells migrate within the fibrotic lung, navigating regional differences in collagen topography. In vitro, KRT5+ cell migratory characteristics and expression of remodelling genes are modulated by extracellular matrix (ECM) composition and organisation. Mass spectrometry- based proteomics revealed compositional differences in ECM components secreted by primary human lung fibroblasts (HLF) from IPF patients compared to controls. Over-expression of ECM glycoprotein, Secreted Protein Acidic and Cysteine Rich (SPARC) in the IPF HLF matrix restricts KRT5+ cell migration in vitro. Together, our findings demonstrate how changes to the ECM in IPF directly influence KRT5+ cell behaviour and function contributing to remodelling events in the fibrotic niche.

Inhibition of the ERK1/2-ubiquitous calpains pathway attenuates experimental pulmonary fibrosis in vivo and in vitro

Idiopathic pulmonary fibrosis (IPF) is a fibrotic lung disease with poor prognosis. Epithelial-mesenchymal transition (EMT) has been reported to play an important role in IPF. The extracellular signal-regulated kinases 1 and 2 (ERK1/2) cascade, which regulates EMT and oncogenesis, has been implicated in the pathogenesis of IPF. Calpains, Ca2+-dependent cysteine proteinases that mediate controlled proteolysis of many specific substrates including epithelial cell marker E-cadherin, participate in organ fibrosis. Calpain-1 and calpain-2 of calpain family are ubiquitous calpains. ERK1/2 signaling stimulates the ubiquitous calpains activity in cancer development, but whether ERK1/2 signaling mediates the ubiquitous calpains activity in pulmonary fibrosis is unknown. Here we investigated whether inhibition of ERK1/2 signaling and the ubiquitous calpains attenuated experimental pulmonary fibrosis and examined the potential mechanism. Our results showed that inhibition of ERK1/2 signaling and the ubiquitous calpains both attenuated bleomycin (BLM)-induced lung fibrosis in mice. Inhibition of ERK1/2 signaling downregulated the expression of calpain-1 and calpain-2 in vivo and in vitro. We detected decreased E-cadherin expression and increased calpain-1 expression in IPF patients. Inhibition of ERK1/2 signaling and the ubiquitous calpains both suppressed the development of EMT in vivo and in vitro. Our study indicated that inhibition of the ERK1/2-ubiquitous calpains pathway protected pulmonary fibrosis from BLM, possibly via inhibition of EMT. Therefore, targeting ubiquitous calpains may be a potential strategy to attenuate IPF.

Fendrr involves in the pathogenesis of cardiac fibrosis via regulating miR-106b/SMAD3 axis

Cardiovascular diseases (CVDs) is the first cause of death worldwide, generally exhibiting a high morbidity, high disability rate and high mortality especially in the elderly persons (>50 years old). Previously, extensive studies have demonstrated that cardiac fibrosis plays cardinal roles in the pathogenesis of CVDs. However, due to the unclear underlying mechanisms of cardiac fibrosis, its clinical intervention remains very lacking. Long non-coding RNAs (lncRNAs), a class of non-coding RNA but differing from microRNAs, are generally considered as transcripts with a length ranging 200 to 100 nucleotides. Recently, accumulating evidence showed that lncRNAs involve in the pathogenesis of cardiac fibrosis. Fendrr (FOXF1 adjacent non-coding developmental regulatory RNA), is a spliced long non-coding RNA transcribed bi-directionally with FOXF1 on the opposite strand. Fendrr has been demonstrated to be essential for normal development of the heart and body wall in mouse, and shows a good anti-fibrotic activity in pulmonary fibrosis. In this study, we aimed to explore the effects of Fendrr on cardiac fibrosis. Intriguingly, we first observed that lncRNA Fendrr was up-regulated in the heart tissues of transverse aortic constriction (TAC) induced cardiac fibrosis mouse models, determined by RT-QPCR. Loss-function of Fendrr significantly alleviated the cardiac fibrosis phenotypes induced by TAC, indicating that Fendrr is required for the pathogenesis of cardiac fibrosis. In mechanism, we demonstrated experimentally that Fendrr directly targeting miR-106b, by which the lncRNA promotes cardiac fibrosis (indicated by the elevation of Col1a1, Col3a1, CTGF and ACTA2 expression) in a miR-106b mediated manner. Collectively, our findings highlight the axis of Fendrr/miR-106b/Samd3 in the pathogenesis of cardiac fibrosis, which may be a promising target for clinical intervention target of cardiac fibrosis.

Macrophage-derived MCPIP1 mediates silica-induced pulmonary fibrosis via autophagy

BackgroundSilicosis is characterized by accumulation of fibroblasts and excessive deposition of extracellular matrix. Monocyte chemotactic protein-1-induced protein 1 (MCPIP1) plays a critical role in fibrosis induced by SiO2. However, the details of the downstream events of MCPIP1 activity in pulmonary fibrosis remain unclear. To elucidate the role of MCPIP1-induced autophagy in SiO2-induced fibrosis, both the upstream molecular mechanisms and the functional effects of SiO2 on cell apoptosis, proliferation and migration were investigated.ResultsExperiments using primary cultures of alveolar macrophages from healthy donors and silicosis patients as well as differentiated U937 macrophages demonstrated the following results: 1) SiO2 induced macrophage autophagy in association with enhanced expression of MCPIP1; 2) autophagy promoted apoptosis and activation of macrophages exposed to SiO2, and these events induced the development of silicosis; 3) MCPIP1 facilitated macrophage apoptosis and activation via p53 signaling-mediated autophagy; and 4) SiO2-activated macrophages promoted the proliferation and migration of fibroblasts via the MCPIP1/p53-mediated autophagy pathway.ConclusionsOur results elucidated a link between SiO2-induced fibrosis and MCPIP1/p53 signaling-mediated autophagy. These findings provide novel insight into the potential targeting of MCPIP1 or autophagy in the development of potential therapeutic strategies for silicosis.Electronic supplementary materialThe online version of this article (doi:10.1186/s12989-016-0167-z) contains supplementary material, which is available to authorized users.

Regulation of 26S Proteasome Activity in Pulmonary Fibrosis.

The ubiquitin-proteasome system is critical for maintenance of protein homeostasis by degrading polyubiquitinated proteins in a spatially and temporally controlled manner. Cell and protein homeostasis are altered upon pathological tissue remodeling. Dysregulation of the proteasome has been reported for several chronic diseases of the heart, brain, and lung. We hypothesized that proteasome function is altered upon fibrotic lung remodeling, thereby contributing to the pathogenesis of idiopathic pulmonary fibrosis (IPF). To investigate proteasome function during myofibroblast differentiation. We treated lung fibroblasts with transforming growth factor (TGF)-β and examined proteasome composition and activity. For in vivo analysis, we used mouse models of lung fibrosis and fibrotic human lung tissue. We demonstrate that induction of myofibroblast differentiation by TGF-β involves activation of the 26S proteasome, which is critically dependent on the regulatory subunit Rpn6. Silencing of Rpn6 in primary human lung fibroblasts counteracted TGF-β-induced myofibroblast differentiation. Activation of the 26S proteasome and increased expression of Rpn6 were detected during bleomycin-induced lung remodeling and fibrosis. Importantly, Rpn6 is overexpressed in myofibroblasts and basal cells of the bronchiolar epithelium in lungs of patients with IPF, which is accompanied by enhanced protein polyubiquitination. We identified Rpn6-dependent 26S proteasome activation as an essential feature of myofibroblast differentiation in vitro and in vivo, and our results suggest it has an important role in IPF pathogenesis.

Northeast Chinese Herbs against Pulmonary Fibrosis Screening Experiment

Objective:To screen the Chinese herbal medicine with anti-pulmonary fibrosis, to provide reference for further study on anti-drug pulmonary fibrosis. Methods By complement lysis test, oleinic acid model of rats and paraquat model of mice were made as pulmonary fibrosis animal model to screen the medicine activity. Results in vitro, Cangzhu and Tinglizi had great significance in inhibition of RBC hemolysis; in vivo, compared with Control group, Hyp content of lung tissues in animal model groups had statistical significance; compared with model group, Hyp content of therapy groups had statistical significance, pathological lesion was reduced. Conclusion Extracts of Cangzhu and Tinglizi has certain resistance to pulmonary fibrosis activity.

Noninvasive Monitoring of Pulmonary Fibrosis by Targeting Matrix Metalloproteinases (MMPs)

While idiopathic pulmonary fibrosis (PF) is a devastating lung disease, the management of PF including effective monitoring of disease progression remains a challenge. Herein, we introduce a novel, fast, and ultrasensitive metalloproteinase (MMP) activatable optical probe, named MMP-P12, to noninvasively monitor PF progression and response to PF treatment. A bleomycin (BLM)-induced mouse PF model was subjected noninvasively to optical imaging at various time points after BLM treatment. The mouse PF model developed fibrosis during 21 days of experimental period, and the progression of PF was well correlated with the stepwise increase of MMP-2 expression as examined by quantitative RT-PCR and Western blot analysis on the 7-, 14-, and 21-day post-BLM administration. On these days, MMP-activated fluorescence images were acquired in vivo and ex vivo. Signal quantification showed time-dependent lung-specific incremental increases in fluorescence signals. As a treatment for PF, secretoglobin 3A2 was daily administered intravenously for five days starting on day seven of BLM administration, which resulted in reduced MMP-2 activity and reduction of PF as previously demonstrated. Importantly, the fluorescence signal that reflected MMP activity also decreased in intensity. In conclusion, MMPs may play an important role in PF development and the MMP-P12 probe could be a promising tool for PF detection, even at an early stage of the disease as well as an indicator of therapy response.

Use of Serum Clara Cell 16-kDa (CC16) Levels as a Potential Indicator of Active Pulmonary Fibrosis in Systemic Sclerosis

To clarify the clinical significance of concentrations of serum Clara cell 16-kDa protein (CC16; previously denoted CC10) in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc); and to compare CC16 levels with levels of the current most reliable serum markers for PF, such as Krebs von den Lungen-6 (KL-6) antigen and surfactant protein-D (SP-D). Serum levels of CC16, KL-6, and SP-D were determined by ELISA in 92 patients with SSc, 20 patients with systemic lupus erythematosus (SLE), and 20 healthy controls. In a retrospective longitudinal study, correlation of serum CC16 levels with the activity of PF was assessed in 16 SSc patients with PF. Although CC16 levels were higher in patients with SSc than in SLE patients or healthy controls, the difference was not significant. Increased serum CC16 levels were associated with involvement of PF, especially active PF, as well as KL-6 and SP-D. Receiver operating characteristic curve analysis revealed that the utility of CC16 is slightly inferior to KL-6, but was comparable with that of SP-D for detecting PF in patients with SSc. In the longitudinal study, serum levels of CC16, KL-6, and SP-D were significantly decreased in the inactive disease phase compared to the active disease phase. CC16 levels can be used as a potential serum biomarker for PF in addition to KL-6 and SP-D in patients with SSc.

Serum pulmonary and activation‐regulated chemokine/CCL18 levels in patients with systemic sclerosis: A sensitive indicator of active pulmonary fibrosis

To clarify the clinical significance of serum levels of pulmonary and activation-regulated chemokine (PARC) in the diagnosis and monitoring of pulmonary fibrosis (PF) in patients with systemic sclerosis (SSc) and to compare PARC levels with KL-6 antigen or surfactant protein D (SP-D) levels. Serum PARC levels were determined by enzyme-linked immunosorbent assay in 123 SSc patients. In a retrospective longitudinal study, correlation of serum PARC levels with the activity of PF was assessed in 21 SSc patients with active PF. PARC levels at the first visit were higher in patients with SSc than in patients with systemic lupus erythematosus (SLE) or healthy controls. Increased serum PARC levels were associated with involvement of PF, decreased diffusing capacity for carbon monoxide, and decreased vital capacity in SSc patients. In the longitudinal study, serum PARC levels were significantly decreased in SSc patients with inactive PF compared with those with active PF. Elevated serum PARC levels correlated with PF and more sensitively reflected the PF activity than did serum KL-6 or SP-D levels in SSc. Serum PARC levels may be a useful new serum marker for active PF in SSc.

Pulmonary fibrosis in myeloperoxidase antineutrophil cytoplasmic antibody-associated vasculitides.

The association of pulmonary fibrosis (PF) with myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA)-associated vasculitides has not been well documented. The aim of this study was to assess the clinicopathological characteristics of PF in patients who tested positive for MPO-ANCA. In this study, 31 patients (17 males and 14 females; mean age, 69 years) diagnosed as having PF with positive MPO-ANCA levels ranging from 10 to 840 EU with a mean of 112.5 EU, were evaluated clinicopathologically. Among 31 patients with PF, 22 had underlying systemic diseases such as collagen vascular diseases, while nine had unknown aetiology. Evidence of glomerulonephritis was demonstrated in 14 patients. The clinical features were a history of dry cough and/or fine crackles in all 31 patients. Chest CT scans showed honeycombing in the lung bases in 26 patients. The histopathological features of the diseased lung tissues in all 11 autopsied cases were compatible with the usual interstitial pneumonia (UIP) pattern. Vasculitis was confirmed in bronchial arteries and/or pulmonary arterioles in five patients. The mortality was as high as 13 of the 31 patients. The causes of death were: deterioration of PF in five (two of whom were associated with pulmonary haemorrhage), lung cancer in two, pneumonia in four, and digestive tract bleeding in two. The survival rates in PF with MPO-ANCA-negative collagen vascular diseases, cryptogenic fibrosing alveolitis (CFA), and PF with positive MPO-ANCA, were compared. The 5-year survival rate in PF with positive MPO-ANCA was worse than in PF with MPO-ANCA-negative collagen vascular diseases and was the same for CFA. Although there was no correlation between MPO-ANCA titres and the activity of PF, this study demonstrated that the presence of positive MPO-ANCA was an unfavorable prognostic factor in patients with PF.