Mechanically Ultra-Robust Fluorescent Elastomer for Elaborating Auxetic Composite.

Fluorescent elastomers are predominantly fabricated through doping fluorescent components or conjugating chromophores into polymer networks, which often involves detrimental effects on mechanical performance and also makes large-scale production difficult. Inspired by the heteroatom-rich microphase separation structures assisted by intensive hydrogen bonds in natural organisms, an ultra-robust fluorescent polyurethane elastomer is reported, which features a remarkable fracture strength of 87.2 MPa with an elongation of 1797%, exceptional toughness of 678.4 MJ m-3 and intrinsic cyan fluorescence at 445 nm. Moreover, the reversible fluorescence variation with temperature could in situ reveal the microphase separation of the elastomer in real time. By taking advantage of mechanical properties, intrinsic fluorescence and hydrogen bonds-promoted interfacial bonding ability, this fluorescent elastomer can be utilized as an auxetic skeleton for the elaboration of an integrated auxetic composite. Compared with the auxetic skeleton alone, the integrated composite shows an improved mechanical performance while maintaining auxetic deformation in a large strain below 185%, and its auxetic process can be visually detected under ultraviolet light by the fluorescence of the auxetic skeleton. The concept of introducing hydrogen-bonded heteroatom-rich microphase separation structures into polymer networks in this work provides a promising approach to developing fluorescent elastomers with exceptional mechanical properties.

Unlocking Auxetic Behavior in Recyclable Thermosetting Foams Enabled by Dynamic Disulfide Cross-linking Strategy.

Auxetic foams with a negative Poisson's ratio (NPR) have attracted considerable attention in material engineering due to their outstanding performance in seismic and energy absorption. Nevertheless, thermoplastic auxetic foams are compromised by weak non-covalent crosslinking that diminishes the mechanical strength and durability of foams. Conversely, thermosetting foams with chemical crosslinking, although mechanically robust, face challenges in elaborating auxetic structure and in achieving recyclability. Herein, an alternative approach is proposed to tackle this dilemma by incorporating dynamic disulfide bonds into the polymer network for preparing a thermosetting polyurethane foam with covalent adaptable network. By leveraging the unidirectional multi-effect compression technique, the topological network reorganization of foam is induced, transforming the initial circular open-cell structure into a re-entrant cell structure. This structural transformation endows the foam with stable NPR capability, achieving a minimum Poisson's ratio value of -0.4 within 30% compressive strain. Benefiting from its reinforced network structure, the foam also demonstrates high compressive strength (6.47 MPa) and tensile strength (1.67 MPa). Furthermore, it is recyclable and can be recompressed into thermosetting films. This work offers a straightforward approach to making auxetic thermosetting foams with good mechanical and recyclable properties, which is interesting for the development of high-performance auxetic materials.

IL-27 induces autophagy through regulation of the DNMT1/lncRNA MEG3/ERK/p38 axis to reduce pulmonary fibrosis.

PURPOSE: Previous studies have shown that interleukin-27 (IL-27) can reduce bleomycin (BLM)-induced pulmonary fibrosis (PF). However, the underlying mechanism by which IL-27 attenuates PF is not fully clear. METHODS: In this research, we used BLM to construct a PF mouse model, and MRC-5 cells stimulated by transforming growth factor-ß1 (TGF-ß1) were used to construct a PF model in vitro. The lung tissue status was observed by Masson and hematoxylin and eosin (HE) staining. To detect gene expression, RT‒qPCR was used. The protein levels were detected by western blotting and immunofluorescence staining. EdU and ELISA were used to detect cell proliferation viability and hydroxyproline (HYP) content, respectively. RESULTS: Aberrant IL-27 expression was observed in BLM-induced mouse lung tissues, and the use of IL-27 attenuated mouse lung tissue fibrosis. TGF-ß1 induced autophagy inhibition in MRC-5 cells, and IL-27 alleviated MRC-5 cell fibrosis by activating autophagy. The mechanism is inhibition of DNA methyltransferase 1 (DNMT1)-mediated lncRNA MEG3 methylation and ERK/p38 signaling pathway activation. Overexpression of DNMT1, knockdown of lncRNA MEG3, autophagy inhibitor or ERK/p38 signaling pathway inhibitors reversed the positive effect of IL-27 in a lung fibrosis model in vitro. CONCLUSION: In conclusion, our study shows that IL-27 upregulates MEG3 expression through inhibition of DNMT1-mediated lncRNA MEG3 promoter methylation, which in turn inhibits ERK/p38 signaling pathway-induced autophagy and attenuates BLM-induced PF, providing a contribution to the elucidation of the potential mechanisms by which IL-27 attenuates PF.

Rapamycin attenuates the paraquat-induced pulmonary fibrosis through activating Nrf2 pathway.

Oxidative stress is a key regulator of idiopathic pulmonary fibrosis. Paraquat (PQ)-induced pulmonary fibrosis seriously endangers people's health. Rapamycin has been reported to alleviate PQ-induced pulmonary fibrosis, but its underlying mechanism is unclear. The nuclear factor E2-related factor 2 (Nrf2) plays an important regulatory role in the antioxidant therapy of PQ-induced pulmonary fibrosis. In this study, we tried to confirm that rapamycin attenuates PQ-induced pulmonary fibrosis by regulating Nrf2 pathway. In vivo, we proved that rapamycin could inhibit the degree of PQ-induced oxidant stress as well as enhanced the expression of Nrf2. In vitro, rapamycin decreased the upregulated effects of cell death and apoptosis, fibrosis-related factors expression and fibroblast-to-myofibroblast transformation by PQ treatment. In vivo, rapamycin treatment reduced fibrosis degree and the expression of fibrosis-related factors in lung tissues of rat treated PQ. Furthermore, we also found that Nrf2 knockdown reduced the inhibitory effect of rapamycin on PQ-induced pulmonary fibrosis, as well as decreased Nrf2 transfer from the cytoplasm into the nucleus. Our findings demonstrated that the protective effect of rapamycin is associated with the activation of the Nrf2 pathway in pulmonary fibrosis induced by PQ poisoning.

Inhibitory effect of circulating fibrocytes on injury repair in acute lung injury/acute respiratory distress syndrome mice model.

The study was aimed to explore the functions of circulating fibrocytes (CFs) on injury repair in acute lung injury/acute respiratory distress syndrome (ALI/ARDS) mice model and its clinical value as a biomarker for ALI/ARDS. ALI/ARDS mice model was established by intratracheal instillation of lipopolysaccharide (LPS). Mononuclear cells were isolated from peripheral blood of ALI/ARDS model and flow cytometry was used to measure CFs defined as cells positive for CD45 and collagen-1. Histological changes of lung tissues were evaluated by H&E staining and Masson's trichrome staining. The correlations of CFs counts with damnification of lung tissue and the severity of pulmonary fibrosis were evaluated by Pearson correlation analyses. Western blot was used to detect the protein expression of collagen-1. ELISA was applied to determine cytokine CXCL12 concentration. Clinical relevance between CFs and ALI/ARDS was investigated. The greater number of CFs in the ALI/ARDS group implied higher degree of lung injury and more severe pulmonary fibrosis. The protein expression of collagen-1 and concentration of cytokine CXCL12 in ALI/ARDS group were higher than that in control group. Clinical and prognostic analysis revealed the higher injury degree and death rates in ALI/ARDS group than those in control group, and identified a greater severity and mortality for patients with ARDS than those with ALI. ROC curve analysis indicated the counts of CFs greater than 5.85% can predict death rates with AUC = 0.928. CFs had an inhibitory effect on injury repair in ALI/ARDS mice model. This might be unfavorable as a clinical marker for progression of ALI/ARDS.

Fibrocytes Ameliorate Acute Lung Injury by Decreasing Inflammatory Cytokine and Chemokine Levels and Reducing Neutrophil Accumulation in the Lung.

BACKGROUND/AIMS: Acute lung injury (ALI) remains a severe disease that threatens human life around the world. To decrease the mortality of ALI and improve ALI treatment efficacy, the development of more ALI treatments is urgently needed. Whether fibrocytes directly participate in ALI has not been studied. Therefore, a mouse model of ALI was induced with lipopolysaccharide (LPS). METHODS: Fibrocytes were harvested from peripheral blood mononuclear cells of bleomycin mice and identified by using flow cytometry to detect the expression of molecular makers. The fibrocytes were injected for the treatment of acute lung injury mice. The curative effects were evaluated by using ELISA to determine the cytokines (including TNF-α, IL-6 and IFN-γ) concentrations in bronchoalveolar lavage fluid (BALF) supernatant. RESULTS: The concentrations of cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interferon-γ (IFN-γ) were increased in mice with ALI induced with LPS. The concentrations of TNF-α, IL-6, and IFN-γ as well as their mRNA and protein expression levels were decreased by administration of fibrocytes. The effect of fibrocytes in ameliorating ALI was time dependent. LPS treatment induced an increase in myeloperoxidase (MPO) activity, whereas the fibrocyte treatment caused inhibition of MPO activity as well as expression of the neutrophil-chemoattractant chemokine macrophage inflammatory protein 2 (MIP-2). CONCLUSION: Taken together, these data suggest that fibrocytes ameliorated ALI by suppressing inflammatory cytokines and chemokines as well as by decreasing the accumulation of neutrophils in the lung.

Rapamycin protects against paraquat-induced pulmonary fibrosis: Activation of Nrf2 signaling pathway.

Paraquat (PQ) is a widely used herbicide indeveloping countries worldwide, and pulmonary fibrosis is one of the most typical features of PQ poisoning. The molecular mechanism of PQ toxicity especially how to treat PQ-induced pulmonary fibrosis is still largely unknown. In animal model of pulmonary fibrosis, we used HE staining, western blotting assay and Real-time PCR assay to analyze the effects of rapamycin on the PQ-induced epithelial mesenchymal transition (EMT). We found that PQ induced the pulmonary fibrosis using HE staining and Masson's staining, and up-regulated the activity of HYP and the mRNA expressions of Collagen I and III (COL-1and COL-3) in pulmonary tissues. We also found that rapamycin down-regulated the mesenchymal cell marker Vimentin and up-regulated the epithelial cell marker E-cadherin both in mRNA and protein levels compared with PQ group. And the EMT associated transcription factor Snail was decreased by rapamycin treatment compared with PQ group. And PQ decreased the Nrf2 expression both in mRNA and protein levels, and rapamycin inhibited these effects of PQ. SFN, a activator of Nrf2, could inhibit the EMT and the expression of Snail. And knockdowon of Nrf2 could abolish the inhibitory effects of rapamycin of PQ-induced EMT. In conclusion, rapamycin protects against paraquat-induced pulmonary fibrosis by activation of Nrf2 signaling pathway.

IL-27 inhibits the TGF-ß1-induced epithelial-mesenchymal transition in alveolar epithelial cells.

BACKGROUND: IL-27 is a multifunctional cytokine that has both pro-inflammatory and anti-inflammatory functions. Although IL-27 has been shown to potently inhibit lung fibrosis, the detailed mechanism of IL-27 in this process is poorly understood. Epithelial-mesenchymal transition (EMT) is one of the key mechanisms involved in pulmonary fibrosis. We assessed the effects of IL-27 on TGF-ß1-induced EMT in alveolar epithelial cells. METHODS: A549 cells (a human AEC cell line) were incubated with TGF-ß1, IL-27, or both TGF-ß1 and IL-27, and changes in E-cadherin, ß-catenin, vimentin and a-SMA levels were measured using real-time PCR, western blotting and fluorescence microscopy. The related proteins in the JAK/STAT and TGF-ß/Smad signalling pathways were examined by western blot. RESULTS: IL-27 increased the expression of epithelial phenotypic markers, including E-cadherin and ß-catenin, and inhibited mesenchymal phenotypic markers, including vimentin and a-SMA in A549 cells. Moreover, TGF-ß1-induced EMT was attenuated by IL-27. Furthermore, we found that TGF-ß1 activated the phosphorylation of JAK1, STAT1, STAT3, STAT5, Smad1, Smad3 and Smad5, and IL-27 partially inhibited these changes in this process. When cells were treated with the STAT3 specific inhibitor wp1006 and the Smad3 specific inhibitor SIS3, the inhibition of EMT by IL-27 was significantly strengthened. CONCLUSION: Our results suggest that IL-27 attenuates epithelial-mesenchymal transition in alveolar epithelial cells in the absence or presence of TGF-ß1 through the JAK/STAT and TGF-ß/Smad signalling pathways.

IL-27 alleviates the bleomycin-induced pulmonary fibrosis by regulating the Th17 cell differentiation.

BACKGROUND: Interleukin-27 (IL-27) is a multifunctional cytokine with both pro-inflammatory and immunoregulatory functions. At present, the role of IL-27 in pulmonary fibrosis remains unknown. METHODS: In this study, we observed the expression of IL-27/IL-27R in a mouse model of bleomycin (BLM)-induced pulmonary fibrosis. We verified the role of IL-27 using hematoxylin and eosin as well as Masson's staining methods and measuring the content of hydroxyproline as well as collagen I and III. We assessed the differentiation of T lymphocytes in the spleen and measured the concentration of cytokines in bronchoalveolar lavage fluid (BALF) and the expression level of relevant proteins in the JAK/STAT and TGF-ß/Smad signaling pathways in lung tissue. RESULTS: Increased IL-27 expression in BLM-induced pulmonary fibrosis was noted. IL-27 treatment may alleviate pulmonary fibrosis and increase the survival of mice. IL-27 inhibited the development of CD4(+) IL-17(+), CD4(+) IL-4(+) T, and CD4(+) Foxp3(+) cells and the secretion of IL-17, IL-4, IL-6, and TGF-ß. IL-27 induced the production of CD4(+) IL-10(+) and CD4(+) INF-γ(+) T cells. IL-27 decreased the levels of phosphorylated STAT1, STAT3, STAT5, Smad1, and Smad3 but increased the level of SOCS3. CONCLUSIONS: This study demonstrates that IL-27 potentially attenuates BLM-induced pulmonary fibrosis by regulating Th17 differentiation and cytokine secretion.

Drp1-mediated mitochondrial fission promotes pulmonary fibrosis progression through the regulation of lipid metabolic reprogramming by ROS/HIF-1α.

OBJECTIVE: To confirm the mechanism of dynamic-related protein 1 (Drp1)-mediated mitochondrial fission through ROS/HIF-1α-mediated regulation of lipid metabolic reprogramming in the progression of pulmonary fibrosis (PF). METHODS: A mouse model of PF was established by intratracheal instillation of bleomycin (BLM) (2.5 mg/kg). A PF cell model was constructed by stimulating MRC-5 cells with TGF-ß (10 ng/mL). Pathological changes in the lung tissue and related protein levels were observed via tissue staining. The indicators related to lipid oxidation were detected by a kit, and lipid production was confirmed through oil red O staining. Inflammatory factors were detected by enzyme-linked immunosorbent assay (ELISA). RT-qPCR, Western blotting and immunofluorescence staining were used to detect the expression of genes and proteins related to the disease. We used CCK-8 and EdU staining to confirm cell proliferation, flow cytometry was used to confirm apoptosis and ROS levels, α-SMA expression was detected by immunofluorescence staining, and mitochondria were observed by MitoTracker staining. RESULTS: The BLM induced lung tissue structure and alveolar wall thickening in mice. Mitochondrial fission was observed in MRC-5 cells induced by TGF-ß, which led to increased cell proliferation; decreased apoptosis; increased expression of collagen, α-SMA and Drp1; and increased lipid oxidation and inflammation. Treatment with the Drp1 inhibitor mdivi-1 or transfection with si-Drp1 attenuated the induction of BLM and TGF-ß. For lipid metabolism, lipid droplets were formed in BLM-induced lung tissue and in TGF-ß-induced cells, fatty acid oxidation genes and lipogenesis-related genes were upregulated, ROS levels in cells were increased, and the expression of HIF-1α was upregulated. Mdivi-1 treatment reversed TGF-ß induction, while H2O2 treatment or OE-HIF-1α transfection reversed the effect of mdivi-1. CONCLUSION: In PF, inhibition of Drp1 can prevent mitochondrial fission in fibroblasts and regulate lipid metabolism reprogramming through ROS/HIF-1α; thus, fibroblast activation was inhibited, alleviating the progression of PF.

siRNA-Act1 inhibits the function of IL-17 on lung fibroblasts via the NF-κB pathway.

BACKGROUND: Interleukin (IL)-17-producing T lymphocytes play a role in pulmonary fibrosis, but the possible mechanism of IL-17 on lung fibroblasts remains uncertain. OBJECTIVES: To explore the role and possible mechanism of IL-17 on lung fibroblasts. METHODS: A mouse model of pulmonary fibrosis was established by intratracheal administration of 5 mg/kg bleomycin. At 14 days following bleomycin administration the pulmonary fibroblasts were isolated, cultured and identified. siRNA for activator 1 (Act1) were transfected into lung fibroblasts, which were cocultured with IL-17. The NF-κB pathway was detected for IL-17 on the lung fibroblasts. RESULTS: IL-17R was increased significantly at 14 days in the bleomycin-induced pulmonary fibroblast model, exogenous IL-17 significantly promoted the proliferation of the pulmonary fibroblasts in primary culture and obviously increased the expression of α-smooth muscle actin and type I and type III collagen in the fibroblasts. We found that IL-17 rapidly activated the NF-κB signaling pathway through activated phosphorylated p65 and IκB, and all roles of IL-17 on lung fibroblasts were inhibited under the interference for the expression of Act1 in lung fibroblasts. CONCLUSION: IL-17 may directly promote the proliferation, transformation and collagen synthesis of lung fibroblasts via the NF-kB signaling pathway, which can be inhibited by the interference for the expression of Act1.

SUMOylation of SMAD4 by PIAS1 in Conjunction with Vimentin Upregulation Promotes Migration Potential in Non-Small Cell Lung Cancer.

BACKGROUND: The expression of vimentin as a marker of epithelial-to-mesenchymal transition (EMT) has been speculated to be associated with tissue heterogeneity and metastases of non-small cell lung cancer (NSCLC). METHODS: This study utilized in vitro co-immunoprecipitation with small interfering RNAs (siRNAs) against protein inhibitors of STAT system type 1 (PIAS1) or SMAD4 in transforming growth factor-beta (TGF-ß) signaling pathway in combination with SUMOylation assay. RESULTS: We successfully demonstrated that PIAS1 enhanced SUMOylation of SMAD4 by forming a complex PIAS1-SUMO1-SMAD4 protein complex. This, in accordance with subsequently increased production of vimentin microfilaments, led to enhanced migration ability of non-small cell lung cancer (NSCLC) A549 line, observed from wound healing assay. CONCLUSIONS: Our results further supported the positive correlation of SUMOylated SMAD4 mediated by PIAS1 and downstream overexpression of vimentin. In addition, the observation that overexpression of vimentin in this certain cell line was not necessarily linked with accelerated relative wound closure raised concerns that further exploration will be needed to confirm if the causal relationship exists between vimentin expression and the metastases of NSCLC, and if so, to what extent vimentin contributes to it.

Sestrin2 Regulates Endoplasmic Reticulum Stress-Dependent Ferroptosis to Engage Pulmonary Fibrosis by Nuclear Factor Erythroid 2-Related Factor 2/Activating Transcription Factor 4 (NRF2/ATF4).

Pulmonary fibrosis (PF) can lead to chronic inflammation, the destruction of alveoli and irreversible lung damage. Sestrin2 is a highly protective stress-inducible protein that is involved in the cell response to various stress factors and the regulation of homeostasis and has a certain protective effect against PF. In this study, TGF-ß1 was used to establish a PF cell model. Bleomycin was used to induce PF in mice, and the expression levels of related proteins were detected by western blotting. The levels of the inflammatory cytokine, TNF-α, IL-6, and IL-1ß were detected by enzyme-linked immunosorbent assays. Immunoprecipitation was used to verify the interaction between ATF4 and NRF2 and between Sestrin2 and NRF2 to explore the specific mechanism by which Sestrin2 affects PF. The results showed that Sestrin2 inhibited fibroblast-to-myofibroblast transition (FMT), improved inflammation, promoted cell proliferation, and alleviated PF. Activating transcription factor 4/nuclear factor erythroid 2-related factor 2 (NRF2/ATF4) signaling pathway activation could alleviate endoplasmic reticulum stress, inhibit ferroptosis and FMT, and reduce reactive oxygen species levels, thereby alleviating PF. Overexpression of ATF4 and the addition of a ferroptosis inducer reversed Sestrin2-mediated alleviation of PF. In conclusion, Sestrin2 alleviates PF and endoplasmic reticulum stress-dependent ferroptosis through the NRF2/ATF4 pathway.

The utility of quantitative computed tomography in cohort studies of chronic obstructive pulmonary disease: a narrative review.

Background and Objective: Chronic obstructive pulmonary disease (COPD) is a significant contributor to global morbidity and mortality. Quantitative computed tomography (QCT), a non-invasive imaging modality, offers the potential to assess lung structure and function in COPD patients. Amidst the coronavirus disease 2019 (COVID-19) pandemic, chest computed tomography (CT) scans have emerged as a viable alternative for assessing pulmonary function (e.g., spirometry), minimizing the risk of aerosolized virus transmission. However, the clinical application of QCT measurements is not yet widespread enough, necessitating broader validation to determine its usefulness in COPD management. Methods: We conducted a search in the PubMed database in English from January 1, 2013 to April 20, 2023, using keywords and controlled vocabulary related to QCT, COPD, and cohort studies. Key Content and Findings: Existing studies have demonstrated the potential of QCT in providing valuable information on lung volume, airway geometry, airway wall thickness, emphysema, and lung tissue density in COPD patients. Moreover, QCT values have shown robust correlations with pulmonary function tests, and can predict exacerbation risk and mortality in patients with COPD. QCT can even discern COPD subtypes based on phenotypic characteristics such as emphysema predominance, supporting targeted management and interventions. Conclusions: QCT has shown promise in cohort studies related to COPD, since it can provide critical insights into the pathogenesis and progression of the disease. Further research is necessary to determine the clinical significance of QCT measurements for COPD management.

The diagnostic value of interleukin-36 cytokines in pleural effusions of varying etiologies.

BACKGROUND: The clinical management of pleural effusion (PE) poses challenges due to its diverse etiologies. The objective of this research was to investigate the concentrations of interleukin-36 (IL-36) cytokines in pleural fluid (PF) from different etiologies and assess their diagnostic efficacy in distinguishing the causes of PE. METHODS: This study enrolled 89 patients with confirmed PE, comprising 11 cases classified as transudate, 24 cases as malignant pleural effusion (MPE), 24 cases as tuberculous pleural effusion (TPE), and 30 cases as parapneumonic pleural effusion (PPE). The PPE group was further subdivided into 20 cases of uncomplicated parapneumonic effusion (UPPE) and 10 cases of complicated parapneumonic effusion (CPPE)/empyema. The concentrations of IL-36 cytokines in the PF of all 89 patients were quantified by the enzyme-linked immunosorbent assay (ELISA). RESULTS: IL-36α exhibited excellent diagnostic accuracy in TPE, achieving a sensitivity of 91.7 % and specificity of 83.1 %, along with a cut-off value of 435.3 pg/ml. IL-36Ra also demonstrated relatively favorable diagnostic performance in PPE, with a sensitivity of 80.0 % and specificity of 76.3 %, along with a cut-off value of 390.8 pg/ml. Multivariable logistic regression models were successfully developed for both TPE and PPE, confirming their diagnostic utility. Furthermore, the levels of IL-36Ra were notably elevated in CPPE/empyema in comparison to UPPE. Moreover, in PF, IL-36γ exhibited positive associations with both IL-36α and IL-36Ra. CONCLUSION: IL-36α and IL-36Ra may serve as novel biomarkers for diagnosing TPE and PPE, respectively. The multivariate models established significantly enhance the diagnostic efficacy of both TPE and PPE. Furthermore, IL-36Ra can function as an indicator for assessing the extent of pleural inflammation. Additionally, the interaction among IL-36 cytokines in PF may contribute to their expression modulation.

The role of all-trans retinoic acid in bleomycin-induced pulmonary fibrosis in mice.

Much evidence suggests that immune imbalance in the lung plays a crucial role in the development of pulmonary fibrosis. Recently, all-trans retinoic acid (ATRA) shifting the regulatory T/T-helper 17 (Treg/Th17) profile had been proven in some diseases. However, to date, the effect of ARTA of pulmonary fibrosis has not been examined from this aspect. The objective of this study was to study the effect of ATRA on bleomycin-induced pulmonary fibrosis in mice and its possible mechanism. Pulmonary fibrosis was induced in C57BL/6 male mice by intratracheal instillation of bleomycin (5 mg.kg(-1)), which were randomly divided into control, bleomycin, and ATRA groups. Five mice in each group were sacrificed on day 28 after intratracheal instillation. Hemotoxylin and eosin (H&E) and Masson staining were used for pathological examination, and hydroxyproline in lung tissue was measured. Interleukin (IL)-17A protein expression was observed in lung with immunohistochemistry. The expression of IL-17A, IL-10, IL-6, and transforming growth factor (TGF)-ß mRNAs were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Th17 and Treg expression in spleen lymphocytes were measured by flow cytometry. H&E and masson staining and expression of hydroxyproline showed that ATRA significantly alleviated lung fibrosis than in the bleomycin group. The expression of IL-17A, IL-10, IL-6, and TGF-ß mRNAs were higher in the bleomycin group than in the normal group. ATRA can decrease these cytokines except for IL-10. CD4+CD25+ Treg cell ratio in the bleomycin group was significantly lower than normal, but CD4+IL-17+ T cells was higher; ARTA reversed this kind of expression. ATRA may ease the bleomycin-induced pulmonary fibrosis by inhibiting the expression of IL-6 and TGF-ß, shifting the Treg/Th17 ratio and reducing the secretion of IL-17A.

Role and Mechanism of Keap1/Nrf2 Signaling Pathway in the Regulation of Autophagy in Alleviating Pulmonary Fibrosis.

A variety of internal and external lung diseases may eventually lead to pulmonary fibrosis, and insufficient autophagy is closely related to pulmonary fibrosis. This research is aimed to explore the mechanism of autophagy to alleviate pulmonary fibrosis. Then, a mouse model of pulmonary fibrosis induced by boromycin and histopathological lesions of the lungs of mice were observed by HE staining, which Masson staining assessed the degree of fibrosis in the lung tissue by detecting the expression of hydroxyproline in the tissue. RT-qPCR and western blotting were used to detect the levels of autophagy and Keap1/Nrf2 signaling pathway-related proteins. It was proved that autophagy-related proteins MAP1LC3(LC3) and Beclin 1 were decreased in mice with pulmonary fibrosis, while the expression of p62 was increased. Mice with pulmonary fibrosis worsened after injection of a 3-MA autophagy inhibitor, while injection of autophagy activation of rapamycin agent promoted Nrf2 nuclear mobilization. In a word, autophagy relieves pulmonary fibrosis through the activation of the Keap1/Nrf2 signaling pathway.

hsa_circ_0072309 Expression Profiling in Non-small-Cell Lung Carcinoma and Its Implications for Diagnosis and Prognosis.

Circular RNAs (circRNAs), which fall into the category of endogenous ncRNAs, are linked to disease progression of neoplastic diseases. Whereas, it remains uncharacterized regarding hsa_circ_0072309's function and implications in lung carcinoma (LC). Gene Expression Omnibus (GEO) database was utilized for identifying circRNAs with aberrantly expression in LC. qRT-PCR was responsible for determining hsa_circ_0072309 levels in lung adenocarcinoma (LAC). Also, its involvement in LC cell progression was investigated. Experimentally, hsa_circ_0072309 was identified as one of the most aberrantly down-regulated circRNAs in the GEO database (GSE101684 and GSE112214). qRT-PCR revealed notably down-regulated hsa_circ_0072309 in LAC tissue, which had a close association with adverse 3-year survival, as well as LNM and advanced TNM stage. Based on ROC, the AUC of hsa_circ_0072309 was determined to be 0.887, and its specificity and susceptibility can be improved by combined detection of either CYFRA21-1 or CEA. In a word, hsa_circ_0072309 is lowly expressed in lung cancer patients and the survival rate of lowly expressed patients is significantly lower, a candidate marker with prognostic utility for the disease.

CDKN2B antisense RNA 1 expression alleviates idiopathic pulmonary fibrosis by functioning as a competing endogenouse RNA through the miR-199a-5p/Sestrin-2 axis.

Idiopathic pulmonary fibrosis (IPF) is an idiopathic interstitial lung disease. At present, the pathogenesis of IPF has not been fully elucidated, which has affected the development of effective treatment methods. Here, we explored the function and potential mechanism of long noncoding RNA (lncRNA) CDKN2B antisense RNA 1 (CDKN2B-AS1) in IPF.Transforming growth factor-ß (TGF-ß) and bleomycin (BLM) were used to induce IPF in cells and animal models. Real Time quantitative Polymerase Chain Reaction (RT-qPCR) showed the expression of CDKN2B-AS1, miR-199a-5p and Sestrin-2 (SESN2) in cells and tissues. The double luciferase reporter gene assay confirmed the targeting relationship among CDKN2B-AS1, miR-199a-5p, and SESN2. Related protein levels were detected by Western blot combined with Cell Counting Kit-8 (CCK-8), wound healing, and flow cytometry to analyze cell proliferation, migration, and apoptosis. The pathological characteristics of mouse lung tissue were determined by Hematoxylin-eosin (HE) and Masson staining. We found that the expression of CDKN2B-AS1 was decreased in TGF-ß-treated cells and BLM-treated mice. Overexpression of CDKN2B-AS1 inhibited cell proliferation and migration, promoted apoptosis, decreased the expression of fibrosis-related proteins and promoted autophagy. In addition, overexpression of CDKN2B-AS1 alleviated pulmonary fibrosis in BLM-treated mice. Mechanistically, CDKN2B-AS1 acts as a miR-199a-5p sponge to regulate SESN2 expression. Our results indicate the importance of the CDKN2B-AS1/miR-199a-5p/SESN2 axis.