Echinatin alleviates sepsis severity through modulation of the NF-κB and MEK/ERK signaling pathways.

Sepsis, a frequently fatal condition, emerges from an exaggerated inflammatory response to infection, resulting in multi-organ dysfunction and alarmingly high mortality rates. Despite the urgent need for effective treatments, current therapeutic options remain limited to antibiotics, with no other efficacious alternatives available. Echinatin (Ecn), a potent bioactive compound extracted from the roots and rhizomes of licorice, has gained significant attention for its broad pharmacological properties, particularly its ability to combat oxidative stress. Recent research highlights the crucial role that oxidative stress plays in the onset and progression of sepsis further emphasizing the potential therapeutic value of Ecn in this context. In this study, we explored the protective effects of Ecn in a murine model of sepsis induced by cecal ligation and puncture (CLP). Ecn demonstrated a significant reduction in the levels of inflammatory cytokines and reactive oxygen species (ROS) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Network pharmacology analysis identified 41 targets and top 15 pathways involved in the Ecn-mediated signaling network, revealing that Ecn might exert its effects through key targets including the NF-κB and MAPK signaling pathways. Molecular docking studies suggested a strong affinity between Ecn and MEK, with kinetic simulations and binding energy calculations confirming a stable interaction. Mechanistically, Ecn treatment inhibited NF-κB and the MEK/ERK signaling pathway, as evidenced by decreased phosphorylation of IκBα and nuclear p65, along with reduced phosphorylation of MEK and ERK in both LPS-stimulated RAW 264.7 macrophages and septic mice. Furthermore, the administration of MEK signaling agonists reversed the anti-inflammatory effects of Ecn, indicating the involvement of this signaling pathway in Ecn's protective mechanism. Notably, our investigation revealed that Ecn did not affect bacterial proliferation either in vivo or in vitro, underscoring its specific immunomodulatory effects rather than direct antimicrobial activity. In summation, our findings underscored the potential of Ecn as an innovative therapeutic remedy for sepsis-induced injury, particularly through the regulation of the NF-κB and MEK/ERK signaling pathway. This exploration unveiled a promising therapeutic approach for treating sepsis, supplementing existing interventions and addressing their constraints.

Disrupting redox homeostasis for tumor therapy based on PDT/chemo/ferroptosis therapeutic hybrid liposomes.

Synergistic photodynamic therapy (PDT) with other therapeutic modalities can enhance the therapeutic efficacy of tumor treatment and reduce the adverse effects associated with drug leakage and off-target accumulation. However, shaping combined strategies for synergistic therapy remains challenging. Herein, we developed versatile hybrid liposomes self-assembled from Ce6-lipid conjugates and loaded with the chemo drug doxorubicin (DOX) and ferroptosis inducer Fe3O4 nanoparticles for synergistic PDT/chemo/ferroptosis therapy. Abundant ROS are generated by PDT upon 650 nm light irradiation, Fe3O4-mediated Fenton reaction, and DOX-induced apoptosis. Furthermore, amplifying oxidative stress in cancer cells to disrupt cellular redox homeostasis could accelerate tumor cell death through oxidative damage to lipids, proteins, and DNA. Overall, this work highlights liposome-based therapeutic nanoformulations, thus offering a breakthrough redox homeostasis-based synergistic PDT/chemo/ferroptosis therapy for lung cancer.

Trim27 aggravates airway inflammation and oxidative stress in asthmatic mice via potentiating the NLRP3 inflammasome.

Asthma is a prevalent chronic respiratory disease, yet understanding its ecology and pathogenesis remains a challenge. Trim27, a ubiquitination ligase belonging to the TRIM (tripartite motif-containing) family, has been implicated in regulating multiple pathophysiological processes such as inflammation, oxidative stress, apoptosis, and cell proliferation. However, the role of Trim27 in asthma has not been investigated. Our study found that Trim27 expression significantly increases in the airway epithelium of asthmatic mice. Knockdown of Trim27 expression effectively relieved ovalbumin (OVA)-induced airway hyperresponsiveness (AHR) and lung tissue histopathological changes. Moreover, Trim27 knockdown exhibited a significant reduction in airway inflammation and oxidative stress in asthmatic mice, and in vitro analysis confirmed the favorable effect of Trim27 deletion on inflammation and oxidative stress in mouse airway epithelial cells. Furthermore, our study revealed that deletion of Trim27 in MLE12 cells significantly decreased NLRP3 inflammasome activation, as evidenced by reduced expression of NLRP3, ASC, and pro-IL-1ß mRNA. This downregulation was reversed when Trim27, but not its mutant lacking ubiquitination ligase activity, was replenished in these cells. Consistent with these findings, protein levels of NLRP3, pro-caspase-1, pro-IL-1ß, cleaved-caspase-1, and cleaved-IL-1ß were higher in Trim27-replenished cells compared to cells expressing Trim27C/A. Functionally, the downregulation of IL-1ß and IL-18 levels induced by Trim27 deletion was rescued by replenishing Trim27. Overall, our findings provide evidence that Trim27 contributes to airway inflammation and oxidative stress in asthmatic mice via NLRP3 inflammasome activation, providing crucial insights into potential therapeutic interventions targeting Trim27 as a way to treat asthma.

Unveiling the Intricacies of Autophagy in Asthma: Unraveling Novel Therapeutic Avenues.

Understanding the pathogenesis of different phenotypes of asthma, including glucocorticoid-dependent and glucocorticoid-resistant asthma, is crucial for the development of effective treatments. Autophagy, a fundamental cellular process involved in cell homeostasis, has been implicated in asthma, although the exact mechanisms remain unclear. Recent studies have identified autophagy activation in eosinophilic, neutrophilic, and paucigranulocytic asthma, providing novel insights into the disease. This comprehensive review examines the role of autophagy in the pathogenesis and treatment of asthma, with a focus on various cell types. The goal is to uncover potential therapeutic targets and innovative treatment modalities to improve patient outcomes in clinical settings.

ncRNAs-mediated TIMELESS overexpression in lung adenocarcinoma correlates with reduced tumor immune cell infiltration and poor prognosis.

Lung adenocarcinoma (LUAD) has a poor prognosis. Circadian genes such as TIMELESS have been associated with several pathologies, including cancer. The expression of TIMELESS and the relationship between TIMELESS, infiltration of tumors and prognosis in LUAD requires further investigation. In this study, we investigated the expression of TIMELESS and its association with survival across several types of human cancer using data from The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression Program. Noncoding RNAs (ncRNAs) regulating overexpression of TIMELESS in lung adenocarcinoma (LUAD) were explored with expression, correlation, and survival analyses. Immune cell infiltration and biomarkers were analyzed between different TIMELESS expression levels. The relationship between TIMELESS expression and immunophenoscores, which were used to predict response to immunotherapy, was evaluated. TIMELESS was identified as a potential oncogene in LUAD. NcRNA analysis showed MIR4435-2HG/hsa-miR-1-3p may interact with TIMELESS in a competitive endogenous RNA network in LUAD tumor tissues. Most immune cells were significantly decreased in TCGA LUAD tumor tissues with high TIMELESS expression except for CD4+T cells and Th2 cells. TIMELESS expression in LUAD tumor tissues was significantly negatively correlated with neutrophil biomarkers, dendritic cell biomarkers (HLA-DPB1, HLA-DQB1, HLA-DRA, HLA-DPA1, CD1C) and an immunophenoscore that predicted outcomes associated with the use of immune checkpoint inhibitors. These findings imply that ncRNAs-mediated TIMELESS overexpression in LUAD tumor tissues correlated with poor prognosis, reduced immune cell infiltration in the tumor microenvironment, and poor response to immune checkpoint inhibitors.

Coxsackievirus A6 2C protein antagonizes IFN-ß production through MDA5 and RIG-I depletion.

IMPORTANCE: Coxsackievirus A6 (CV-A6) is a major emerging pathogen associated with atypical hand, foot, and mouth disease and can cause serious complications such as encephalitis, acute flaccid paralysis, and neurorespiratory syndrome. Therefore, revealing the associated pathogenic mechanisms could benefit the control of CV-A6 infections. In this study, we demonstrate that the nonstructural 2CCV-A6 suppresses IFN-ß production, which supports CV-A6 infection. This is achieved by depleting RNA sensors such as melanoma differentiation-associated gene 5 and retinoic acid-inducible gene I (RIG-I) through the lysosomal pathway. Such a function is shared by 2CEV-A71 and 2CCV-B3 but not 2CCV-A16, suggesting the latter might have an alternative way to promote viral replication. This study broadens our understanding of enterovirus 2C protein regulation of the RIG-I-like receptor signaling pathway and reveals a novel mechanism by which CV-A6 and other enteroviruses evade the host innate immune response. These findings on 2C may provide new therapeutic targets for the development of effective inhibitors against CV-A6 and other enterovirus infections.

Ferroptosis in pulmonary fibrosis: an emerging therapeutic target.

In recent years, the role of ferroptosis in pulmonary fibrosis has garnered increasing interest as a potential therapeutic target. Pulmonary fibrosis is a pathological process characterized by the accumulation of extracellular matrix in affected lung tissues, and currently, there are no effective therapies for preventing or reversing the fibrotic lesions. Ferroptosis is a form of programmed cell death that is regulated by a network of enzymes and signaling pathways. Dysregulation of ferroptosis has been implicated in several diseases, including pulmonary fibrosis. The accumulation of lipid peroxides in the course of ferroptosis causes damage to cell membranes and other cellular components, leading ultimately to cell death. Relevant targets for therapeutic intervention in ferroptosis include key enzymes, such as glutathione peroxidase 4, transcription factors like nuclear factor erythroid 2-related factor 2, and iron chelation. This review provides an overview of the emerging role of ferroptosis in pulmonary fibrosis and highlights potential therapeutic targets in this pathway. Further research is needed to develop safe and effective approaches targeting ferroptosis in treatment of pulmonary fibrosis.

Activation of PI3K/Akt pathway by G protein-coupled receptor 37 promotes resistance to cisplatin-induced apoptosis in non-small cell lung cancer.

OBJECTIVES: Lung cancer is a major public health concern and represents the most common cause of cancer-related death worldwide. Among eukaryotes, the G protein-coupled receptor (GPCR) family stands as the largest group of membrane proteins. Alterations in GPCR gene expression and dysregulation of signal transduction have been recognized as the markers of malignancy. As a member of the GPCR family, G protein-coupled receptor 37 (GPR37) exhibits unknown functions in tumors, particularly in non-small-cell lung cancer (NSCLC) METHODS: We explored the expression and prognosis of GPR37 in NSCLC through TCGA, GTEx, GEO, and GEPIA2. We detected the expression of GPR37 in NSCLC tissues and cell lines. The study explored the influence of GPR37 on tumor cell proliferation. Furthermore, we examined the effects of GPR37 on tumor cell apoptosis and invasion. Most importantly, we investigated whether GPR37 affects cisplatin-induced drug resistance in NSCLC. Furthermore, by conducting animal experiments, we assessed the impact of GPR37 on NSCLC and delved into underlying mechanisms. RESULTS: (1) In NSCLC, the expression of GPR37 is markedly higher than that in corresponding normal tissues. We found that elevated GPR37 expression predicts an unfavorable prognosis. (2) It was demonstrated that GPR37 positively regulates NSCLC cell invasion, migration, and proliferation, suppresses cell apoptosis, heightens resistance to cisplatin, and promotes tumor formation and growth. Conversely, we observed that GPR37 knockdown suppresses NSCLC cell invasion, migration, and proliferation, promotes cell apoptosis, increases sensitivity to cisplatin, and affects tumor formation and growth. (3) GPR37 activates PI3K/Akt/mTOR signal transduction pathways to mediate epithelial-mesenchymal transition (EMT), thereby promoting the progression of NSCLC. CONCLUSIONS: It was suggested that GPR37 acts a crucial role in promoting the occurrence and development of NSCLC. Knockdown of GPR37 significantly inhibits the occurrence and development of NSCLC. Therefore, our findings demonstrated that GPR37 may represent a viable therapeutic target for NSCLC.

Modeling human anti-pig xenoimmune responses in a pig artery tissue grafted humanized mouse model.

BACKGROUND: Blood vessels that contain endothelial cells (ECs) on the surface are in direct contact with host blood and are the first target of xenograft rejection. Currently, our understanding of human anti-pig vessel immune responses is primarily based on in vitro assays using pig ECs. Therefore, it is necessary to develop an animal model that permits in vivo study of human immunological rejection of pig vessels. METHODS: Pig artery tissues (PAT) were transplanted into human immune system (HIS) mice or immunodeficient NSG mice (as controls). Intragraft human immune cell infiltration and antibody deposition were quantified using histology and immunohistochemistry. Donor antigen-specific immune responses were quantified using a mixed lymphocyte reaction and a complement-dependent killing assay. RESULTS: Pig CD31+ ECs were detected and increased 2-fold from weeks 3 to 5 in PAT xenografts from immunodeficient NSG mice. However, compared with NSG mice, PAT xenografts in HIS mice had significantly lower numbers of porcine CD31+ ECs and showed a marked reduction from week 3 to week 5. PAT xenograft rejection in HIS mice is associated with intensive infiltration of human immune cells, deposition of human IgM and IgG antibodies, and the formation of a tertiary lymphoid structure. Robust donor pig antigen-specific human T cells and antibody responses were detected in PAT-transplanted HIS mice. CONCLUSION: We have developed a humanized mouse model to evaluate human anti-pig xenoimmune responses by PAT transplantation in vivo. This model is expected to facilitate the refinement of pig gene-editing strategies (the expression on EC surface) and the testing of local immunosuppressive strategies for clinical pig organ xenotransplantation.

The versatile defender: exploring the multifaceted role of p62 in intracellular bacterial infection.

As a highly conserved, multifunctional protein with multiple domains, p62/SQSTM1 plays a crucial role in several essential cellular activities, particularly selective autophagy. Recent research has shown that p62 is crucial in eradicating intracellular bacteria by xenophagy, a selective autophagic process that identifies and eliminates such microorganisms. This review highlights the various roles of p62 in intracellular bacterial infections, including both direct and indirect, antibacterial and infection-promoting aspects, and xenophagy-dependent and independent functions, as documented in published literature. Additionally, the potential applications of synthetic drugs targeting the p62-mediated xenophagy mechanism and unresolved questions about p62's roles in bacterial infections are also discussed.

The Correlation of PM2.5 Exposure with Acute Attack and Steroid Sensitivity in Asthma.

Bronchial asthma is a common chronic inflammatory disease of the respiratory system. Asthma primarily manifests in reversible airflow limitation and airway inflammation, airway remodeling, and persistent airway hyperresponsiveness. PM2.5, also known as fine particulate matter, is the main component of air pollution and refers to particulate matter with an aerodynamic diameter of ≤2.5 µm. PM2.5 can be suspended in the air for an extensive time and, in addition, can contain or adsorb heavy metals, toxic gases, polycyclic aromatic hydrocarbons, bacterial viruses, and other harmful substances. Epidemiological studies have demonstrated that, in addition to increasing the incidence of asthma, PM2.5 exposure results in a significant increase in the incidence of hospital visits and deaths due to acute asthma attacks. Furthermore, PM2.5 was reported to induce glucocorticoid resistance in asthmatic individuals. Although various countries have implemented strict control measures, due to the wide range of PM2.5 sources, complex components, and unknown pathogenic mechanisms involving the atmosphere, environment, chemistry, and toxicology, PM2.5 damage to human health still cannot be effectively controlled. In this present review, we summarized the current knowledge base regarding the relationship between PM2.5 toxicity and the onset, acute attack prevalence, and steroid sensitivity in asthma.

Humanized mice for investigating SARS-CoV-2 lung infection and associated human immune responses.

There is an urgent need for animal models of coronavirus disease 2019 to study immunopathogenesis and test therapeutic intervenes. In this study, we showed that NOD/SCID IL2rg-/- (NSG) mice engrafted with human lung (HL) tissue (NSG-L mice) could be infected efficiently by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and that live virus capable of infecting Vero cells was found in the HL grafts and multiple organs from infected NSG-L mice. RNA-Sequencing identified a series of differentially expressed genes, which are enriched in viral defense responses, chemotaxis, IFN stimulation and pulmonary fibrosis, between HL grafts from infected and control NSG-L mice. Furthermore, when infected with SARS-CoV-2, humanized mice with both human immune system (HIS) and autologous HL grafts (HISL mice) had bodyweight loss and hemorrhage and immune cell infiltration in HL grafts, which were not observed in immunodeficient NSG-L mice, indicating the development of anti-viral immune responses in these mice. In support of this possibility, the infected HISL mice showed bodyweight recovery and lack of detectable live virus at the later time. These results demonstrate that NSG-L and HISL mice are susceptible to SARS-CoV-2 infection, offering a useful in vivo model for studying SARS-CoV-2 infection and the associated immune response and immunopathology, and testing anti-SARS-CoV-2 therapies.

TREX1 plays multiple roles in human diseases.

Three-prime repair exonuclease 1 (TREX1) is a major 3'-5' DNA exonuclease, which digests cytosolic DNA to avoid inappropriate activation of the innate immune system. Besides the most studied exonuclease activity, the recently discovered functions of TREX1, such as regulating the oligosaccharyltransferase complex and triggering proteasome-mediated degradation, are also indispensable to prevent innate immune activation. However, mounting evidence indicates a dual role of TREX1 in human diseases. In cancer and radiotherapy, the digestion of immunogenic DNA by TREX1 inhibits antitumor immunity. Moreover, TREX1 also processes specific chromosomal abnormalities upon nuclear membrane rupture, which induces DNA damage. In this review, we summarize previous studies assessing the function and mechanisms of TREX1 in autoimmune diseases, inflammatory diseases, and cancer and discuss the relationship between the function and its associated diseases. By analyzing the various roles of TREX1 under different conditions, we explored the remaining questions regarding the molecular mechanism of TREX1.

PM2.5 Exposure and Asthma Development: The Key Role of Oxidative Stress.

Oxidative stress is defined as the imbalance between reactive oxygen species (ROS) production and the endogenous antioxidant defense system, leading to cellular damage. Asthma is a common chronic inflammatory airway disease. The presence of asthma tends to increase the production of reactive oxygen species (ROS), and the antioxidant system in the lungs is insufficient to mitigate it. Therefore, asthma can lead to an exacerbation of airway hyperresponsiveness and airway inflammation. PM2.5 exposure increases ROS levels. Meanwhile, the accumulation of ROS will further enhance the oxidative stress response, resulting in DNA, protein, lipid, and other cellular and molecular damage, leading to respiratory diseases. An in-depth study on the relationship between oxidative stress and PM2.5-related asthma is helpful to understand the pathogenesis and progression of the disease and provides a new direction for the treatment of the disease. This paper reviews the research progress of oxidative stress in PM2.5-induced asthma as well as highlights the therapeutic potentials of antioxidant approaches in treatment of asthma.

Regulation of host factor γ-H2AX level and location by enterovirus A71 for viral replication.

Numerous viruses manipulate host factors for viral production. We demonstrated that human enterovirus A71 (EVA71), a primary causative agent for hand, foot, and mouth disease (HFMD), increased the level of the DNA damage response (DDR) marker γ-H2AX. DDR is primarily mediated by the ataxia telangiectasia mutated (ATM), ATM and Rad3-related (ATR), or DNA-dependent protein kinase (DNA-PK) pathways. Upregulation of γ-H2AX by EVA71 was dependent on the ATR but not the ATM or DNA-PK pathway. As a nuclear factor, there is no previous evidence of cytoplasmic distribution of γ-H2AX. However, the present findings demonstrated that EVA71 encouraged the localization of γ-H2AX to the cytoplasm. Of note, γ-H2AX formed a complex with structural protein VP3, non-structural protein 3D, and the viral genome. Treatment with an inhibitor or CRISPR/Cas9 technology to decrease or silence the expression of γ-H2AX decreased viral genome replication in host cells; this effect was accompanied by decreased viral protein expression and virions. In animal experiments, caffeine was used to inhibit DDR; the results revealed that caffeine protected neonatal mice from death after infection with EVA71, laying the foundation for new therapeutic applications of caffeine. More importantly, in children with HFMD, γ-H2AX was upregulated in peripheral blood lymphocytes. The consistent in vitro and in vivo data on γ-H2AX from this study suggested that caffeine or other inhibitors of DDR might be novel therapeutic agents for HFMD.

Characteristics of the Severe Acute Respiratory Syndrome Coronavirus 2 Omicron BA.2 Subvariant in Jilin, China from March to May 2022.

Background and Objectives: In the midst of the pandemic, new coronavirus mutants continue to emerge; the most relevant variant worldwide is omicron. Here, patients who recovered from the disease living in Jilin Province were analyzed to identify factors affecting the severity of omicron infection and to provide insights into its spread and early indication. Methods: In this study, 311 cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were divided into two groups. Data on the patients' demographic characteristics and laboratory tests, including platelet count (PLT), neutrophil count (NE), C-reactive protein (CRP), serum creatinine (SCR), and neutrophil-to-lymphocyte ratio (NLR), were collected. The biomarkers for moderate and severe coronavirus disease 2019 (COVID-19) and factors affecting the incubation period and time to subsequent negative nucleic acid amplification test (NAAT) were also investigated. Results: Age, gender, vaccination, hypertension, stroke, chronic obstructive pulmonary disease (COPD)/chronic bronchitis/asthma, and some laboratory tests were statistically different between the two groups. In the receiver operating characteristic (ROC) analysis, PLT and CRP had higher area under the ROC curve values. In the multivariate analysis, age, hypertension, COPD/chronic bronchitis/asthma, and CRP were correlated with moderate and severe COVID-19. Moreover, age was correlated with longer incubation. In the Kaplan-Meier curve analysis, gender (male), CRP, and NLR were associated with longer time to subsequent negative NAAT. Conclusions: Older patients with hypertension and lung diseases were likely to have moderate or severe COVID-19, and younger patients might have a shorter incubation. A male patient with high CRP and NLR levels might take more time to turn back negative in the NAAT.

Exploration of Human Lung-Resident Immunity and Response to Respiratory Viral Immunization in a Humanized Mouse Model.

There are urgent needs for humanized mouse models of viral respiratory diseases to study immunopathogenesis and therapeutic interventions. Although human immune system (HIS) mice permit analysis in real time of human immune responses in vivo, evolutionary divergences preclude their usefulness for the respiratory viruses that do not infect mouse lungs. In this study, we sought to use HIS mice with human lung (HL) tissue xenografts (HISL mice) to address this issue. The grafted HL tissue maintained histologically normal structure, and populated with human tissue-resident immune cells, including CD11c+ dendritic cells and CD4+ and CD8+ tissue-resident memory T cells. HISL mice showed a marked expansion of tissue-resident memory T cells and generation of viral Ag-specific T cells in the HL xenografts, and production of antiviral IgM and IgG Abs upon immunization of the HL xenograft by H1N1 influenza viruses. RNA-seq analysis on H1N1-infected and control HL xenografts identified a total of 5089 differentially expressed genes with enrichments for genes involved in respiratory diseases, viral infections, and associated immune responses. Furthermore, prophylactic viral exposures resulted in protection against subsequent lethal challenge by intranasal viral inoculation. This study supports the usefulness of this preclinical model in exploring the immunopathology and therapies of respiratory viral diseases.

Specific Deubiquitinating Enzymes Promote Host Restriction Factors Against HIV/SIV Viruses.

Hijacking host ubiquitin pathways is essential for the replication of diverse viruses. However, the role of deubiquitinating enzymes (DUBs) in the interplay between viruses and the host is poorly characterized. Here, we demonstrate that specific DUBs are potent inhibitors of viral proteins from HIVs/simian immunodeficiency viruses (SIVs) that are involved in viral evasion of host restriction factors and viral replication. In particular, we discovered that T cell-functioning ubiquitin-specific protease 8 (USP8) is a potent and specific inhibitor of HIV-1 virion infectivity factor (Vif)-mediated apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3)G (A3G) degradation. Ectopic expression of USP8 inhibited Vif-induced A3G degradation and suppressed wild-type HIV-1 infectivity even in the presence of Vif. In addition, specific DUBs repressed Vpr-, Vpu-, and Vpx-triggered host restriction factor degradation. Our study has revealed a previously unrecognized interplay between the host's DUBs and viral replication. Enhancing the antiviral activity of DUBs therefore represents an attractive strategy against HIVs/SIVs.

MUC5B regulates the airway inflammation induced by atmospheric PM2.5 in rats and A549 cells.

Atmospheric PM2.5 can induce airway inflammation and mucin secretion. MUC5B is required for airway defense. However, the research on the role of MUC5B in airway inflammation induced by atmospheric PM2.5 remains limited. This study was designed to explore the role of MUC5B in airway inflammation induced by atmospheric PM2.5. In vivo, Wistar rats were exposed to 0, 1.5, 7.5, 37.5 mg/ kg PM2.5 saline suspension via intratracheal instillation. HE staining and AB-PAS staining were used to observe the airway inflammation and goblet cell hyperplasia. In vitro, normal A549 cells and MUC5B-knockdown A549 cells were exposed to 0, 100, 200 and 400 µg/mL PM2.5 for 6 h, 12 h, 24 h and 48 h. ELISA was used to measure the levels of TNF-α and IL-1ß in serum and bronchoalveolar lavage fluid of rats and in cell culture. Real time-PCR and ELISA were used to quantify the mRNA and protein levels of MUC5B in trachea and lung of rats and in A549 cells. PM2.5 could cause the infiltration of inflammatory cells and increase the mucus secretions and goblet cell metaplasia. MUC5B is related to rats' airway inflammation induced by PM2.5. A549 cells exposed to PM2.5 in higher concentration and longer time, the protein level of MUC5B was significantly increased, while the levels of IL-1ß, TNF-α and MUC5B mRNA were significantly decreased. Compared with normal A549 cells, the levels of IL-1ß and TNF-α were significantly higher in Muc5b-knockdown cells. Atmospheric PM2.5 can induce airway inflammation and mucin secretion. MUC5B played a critical role in controlling the inflammatory response induced by PM2.5.

MYPT1, regulated by miR-19b-3p inhibits the progression of non-small cell lung cancer via inhibiting the activation of wnt/ß-catenin signaling.

AIMS: Myosin phosphatase targeting protein 1 (MYPT1) was identified to function as a tumor suppressor in several kinds of cancers, but its role and the molecular mechanisms in non-small cell lung cancer (NSCLC) remain undiscovered. Herein, we aimed to reveal MYPT1 expression pattern and role in NSCLC, and investigate the underlying mechanisms. MAIN METHODS: Sixty-eight paired NSCLC tissues and the adjacent normal tissues were included in this study. Western blotting and quantitative reverse transcription-polymerase chain (qPCR) technologies were applied for protein and RNA detection. CCK-8, colony formation, flow cytometry, wound healing, transwell chambers coated with Matrigel and in vivo experiments were applied to detect cell viability, colony formation, apoptosis, migration, invasiveness and tumorigenesis, respectively. KEY FINDINGS: MYPT1 expressed at a lower level in NSCLC tissues as compared with the adjacent normal tissues, which predicted advanced clinic process and poor prognosis. Overexpression of MYPT1 resulted in obvious inhibitions in cell viability, colony formation, migration, invasiveness and tumorigenesis, and induced cell apoptotic rates, as well as decreased the expression levels of ß-catenin and TCF4. Besides, overexpression of ß-catenin weakened the above roles of MYPT1. In addition, the luciferase gene reporter assay verified that MYPT1 was a target of miR-19b-3p. Further experiments showed that miR-19b-3p promoted cell viability, invasiveness and migration and repressed cell apoptosis by targeting MYPT1. SIGNIFICANCE: In conclusion, this study demonstrates that MYPT1, regulated by miR-19b-3p, inhibits the progression of NSCLC via inhibiting the activation of wnt/ß-catenin signaling.