Anti-TNFα therapy in inflammatory lung diseases

Comprehensive pulmonary toxicity assessment of cetylpyridinium chloride using A549 cells and Sprague-Dawley rats

Cetylpyridinium chloride (CPC), a quaternary ammonium compound and cationic surfactant, is used in personal hygiene products such as toothpaste, mouthwash, and nasal spray. Although public exposure to CPC is frequent, its pulmonary toxicity has yet to be fully characterized. Due to high risks of CPC inhalation, we aimed to comprehensively elucidate the in vitro and in vivo toxicity of CPC. The results demonstrated that CPC is highly cytotoxic against the A549 cells with a half-maximal inhibitory concentration (IC₅₀ ) of 5.79 μg/ml. Following CPC exposure, via intratracheal instillation (ITI), leakage of lactate dehydrogenase, a biomarker of cell injury, was significantly increased in all exposure groups. Further, repeated exposure of rats to CPC for 28 days caused a decrease in body weight of the high-exposure group and the relative weights of the lungs and kidneys of the high recovery group, but no changes were evident in the histological and serum chemical analyses. The bronchoalveolar lavage fluid (BALF) analysis showed a significant increase in proinflammatory cytokines interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α levels. ITI of CPC induced focal inflammation of the pulmonary parenchyma in rats' lungs. Our study demonstrated that TNF-α was the most commonly secreted proinflammatory cytokine during CPC exposure in both in vitro and in vivo models. Polymorphonuclear leukocytes in the BALF, which are indicators of pulmonary inflammation, significantly increased in a concentration-dependent manner in all in vivo studies including the ITI, acute, and subacute inhalation assays, demonstrating that PMNs are the most sensitive parameters of pulmonary toxicity.

Progressive Lung Injury, Inflammation, and Fibrosis in Rats Following Inhalation of Sulfur Mustard

Sulfur mustard (SM) inhalation causes debilitating pulmonary injury in humans which progresses to fibrosis. Herein, we developed a rat model of SM toxicity which parallels pathological changes in the respiratory tract observed in humans. SM vapor inhalation caused dose (0.2-0.6 mg/kg)-related damage to the respiratory tract within 3 days of exposure. At 0.4-0.6 mg/kg, ulceration of the proximal bronchioles, edema and inflammation were observed, along with a proteinaceous exudate containing inflammatory cells in alveolar regions. Time course studies revealed that the pathologic response was biphasic. Thus, changes observed at 3 days post-SM were reduced at 7-16 days; this was followed by more robust aberrations at 28 days, including epithelial necrosis and hyperplasia in the distal bronchioles, thickened alveolar walls, enlarged vacuolated macrophages, and interstitial fibrosis. Histopathologic changes were correlated with biphasic increases in bronchoalveolar lavage (BAL) cell and protein content and proliferating cell nuclear antigen expression. Proinflammatory proteins receptor for advanced glycation end product (RAGE), high-mobility group box protein (HMGB)-1, and matrix metalloproteinase (MMP)-9 also increased in a biphasic manner following SM inhalation, along with surfactant protein-D (SP-D). Tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS), inflammatory proteins implicated in mustard lung toxicity, and the proinflammatory/profibrotic protein, galectin (Gal)-3, were upregulated in alveolar macrophages and in bronchiolar regions at 3 and 28 days post-SM. Inflammatory changes in the lung were associated with oxidative stress, as reflected by increased expression of heme oxygenase (HO)-1. These data demonstrate a similar pathologic response to inhaled SM in rats and humans suggesting that this rodent model can be used for mechanistic studies and for the identification of efficacious therapeutics for mitigating toxicity.

Peptide-Based TNF-α-Binding Decoy Therapy Mitigates Lipopolysaccharide-Induced Liver Injury in Mice

A peptide named SEM18, possessing structural similarity to the binding site of tumor necrosis factor (TNF)-α to TNF receptor 1 (TNFR1), was designed. We investigated whether the SEM18 peptide can mitigate lipopolysaccharide (LPS)-induced liver injury in mice. Adult male Balb/cJ mice received LPS (15 mg/kg; LPS group) or LPS plus SEM18 (LSEM group). Control groups were run simultaneously. At 2 h after LPS, the first dose of SEM18 (0.3 mg/kg) was administered, followed by three supplemental doses of SEM18 (0.15 mg/kg, every 2 h). At 24 h after LPS, surviving mice were euthanized for analyses. Compared with the LPS group, binding of TNF-α to TNFR1 in liver tissues was significantly lower in the LSEM group (p < 0.001). Plasma concentrations of aspartate transaminase and alanine transaminase, as well as Suzuki’s scores (liver damage assessment), wet/dry weight ratios, levels of polymorphonuclear neutrophil infiltration, and levels of mitochondrial injury in liver tissues, of the LSEM group were significantly lower than in the LPS group (all p < 0.05). Levels of necroptosis, pyroptosis, apoptosis, and autophagy upregulation in liver tissues in the LSEM group were also significantly lower than in the LPS group (all p < 0.05). Notably, exogenous TNF-α counteracted these effects of SEM18. SEM18 peptide mitigates LPS-induced liver injury in mice.

Biologic Immunomodulatory Drugs and Infection in the Respiratory Tract of Nonhuman Primates

Though rare due to measures and practices to control the risk, infections can occur in research and toxicology studies, especially in nonhuman primates (NHPs) exposed to xenobiotics, particularly immunomodulatory drugs. With such xenobiotics, immunocompromised or immunosuppressed animals will not be able to mount a protective response to infection by an opportunistic pathogen (bacteria, virus, parasite, or fungus) that might otherwise be nonpathogenic and remain clinically asymptomatic in immunocompetent animals. The respiratory tract is one of the most commonly affected systems in clinic, but also in toxicology studies. Pulmonary inflammation will be the main finding associated with opportunistic infections and may cause overt clinical disease with even early sacrifice or death, and may compromise or complicate the pathology evaluation. It is important to properly differentiate the various features of infection, to be aware of the range of possible opportunistic pathogens and how they may impact the interpretation of pathology findings. This review will present the most common bacterial, viral, parasitic, and fungal infections observed in the respiratory tract in NHPs during research and/or toxicology studies.

Treatment of acute lung inflammation by pulmonary delivery of anti-TNF-α siRNA with PAMAM dendrimers in a murine model

To improve the efficacy of nucleic acid-based therapeutics, e.g., small interfering RNA (siRNA), transfection agents are needed for efficient delivery into cells. Several classes of dendrimers have been found useful as transfection agents for the delivery of siRNA because their surface can readily be functionalized, and the size of the dendriplexes they form with siRNA is within the range of conventional nanomedicine. In this study, commercially available generation 3 poly(amidoamine) (PAMAM) dendrimer was investigated for pulmonary delivery of siRNA directed against tumor necrosis factor (TNF) α for the treatment of acute lung inflammation. Delivery efficiency was assessed in vitro in the RAW264.7 macrophage cell line activated with lipopolysaccharide (LPS), and efficacy was evaluated in vivo in a murine model of LPS-induced lung inflammation upon pre-treatment with TNF-α siRNA. The PAMAM dendrimer-siRNA complexes (dendriplexes) displayed strong siRNA condensation and high cellular uptake in macrophages compared with non-complexed siRNA. Q-PCR analyses showed that the dendriplexes mediated efficient and specific TNF-α silencing in vitro, as compared to non-complexed siRNA and dendriplexes with negative control siRNA. Also in vivo, the PAMAM dendriplexes induced efficacious TNF-α siRNA inhibition, as compared to non-complexed siRNA, upon pulmonary administration to mice with LPS-induced lung inflammation. Hence, these data suggest that PAMAM dendrimers are promising for the local delivery of TNF-α siRNA in the treatment of lung inflammation via pulmonary administration.

Association between tumor necrosis factor alpha and obstructive sleep apnea in adults: a meta-analysis update

BACKGROUND

Tumor necrosis factor-α (TNF-α) has been reported to play a part in the development of obstructive sleep apnea (OSA) and its complications. However, the relationship between TNF-α and OSA still remains inconclusive. We aimed to systematically review and synthesize studies published to date on association between the two in adults.

METHODS

We searched for English-language articles containing original human data from case-control study studies in adults≥18 years of age. The selection criteria were set according to the PICOS framework. Articles were independently reviewed by three investigators. Data regarding demographics, clinical characteristics, and TNF-α levels were obtained. A random-effects model was applied to evaluate the overall effect sizes by calculating standard mean difference (SMD) and its 95% confidence intervals (CIs).

RESULTS

Of 393 identified abstracts, 50 articles (3503 OSA patients and 3379 health controls) were ultimately included in this meta-analysis. The results indicated that the TNF-α level in patients with OSA was 1.77 (95%CI, 1.37 to 2.17, I² = 97.8%, P < 0.0001) times higher than in the control group. Subgroup analyses showed a positive correlation between the level of TNF-α and OSA severity. According to meta-regression, we noted that aging significantly predicted an increased effect size of TNF-α level in OSA patients (P < 0.007).

CONCLUSION

This study identified a significant association between OSA and elevated TNF-α level in adults. Meanwhile, TNF-α levels were consistently correlated with severity of OSA, which indicated it might be a promising biomarker for the development of OSA. However, well-designed, large-scale, case-control cohorts are needed to better understand the relationship of TNF-α in the context of adult OSA.

Development of a miniaturized 96-Transwell air-liquid interface human small airway epithelial model

In order to overcome the challenges associated with a limited number of airway epithelial cells that can be obtained from clinical sampling and their restrained capacity to divide ex vivo, miniaturization of respiratory drug discovery assays is of pivotal importance. Thus, a 96-well microplate system was developed where primary human small airway epithelial (hSAE) cells were cultured at an air–liquid interface (ALI). After four weeks of ALI culture, a pseudostratified epithelium containing basal, club, goblet and ciliated cells was produced. The 96-well ALI cultures displayed a cellular composition, ciliary beating frequency, and intercellular tight junctions similar to 24-well conditions. A novel custom-made device for 96-parallelized transepithelial electric resistance (TEER) measurements, together with dextran permeability measurements, confirmed that the 96-well culture developed a tight barrier function during ALI differentiation. 96-well hSAE cultures were responsive to transforming growth factor β1 (TGF-β1) and tumor necrosis factor α (TNF-α) in a concentration dependent manner. Thus, the miniaturized cellular model system enables the recapitulation of a physiologically responsive, differentiated small airway epithelium, and a robotic integration provides a medium throughput approach towards pharmaceutical drug discovery, for instance, in respect of fibrotic distal airway/lung diseases.

The possible mechanisms of action of 4-aminoquinolines (chloroquine/hydroxychloroquine) against Sars-Cov-2 infection (COVID-19): A role for iron homeostasis?

The anti-malarial drugs chloroquine (CQ) and primarily the less toxic hydroxychloroquine (HCQ) are currently used to treat autoimmune diseases for their immunomodulatory and anti-thrombotic properties. They have also been proposed for the treatment of several viral infections, due to their anti-viral effects in cell cultures and animal models, and, currently, for the treatment of coronavirus disease 2019 (COVID-19), the pandemic severe acute respiratory syndrome caused by coronavirus 2 (Sars-Cov-2) infection that is spreading all over the world. Although in some recent studies a clinical improvement in COVID-19 patients has been observed, the clinical efficacy of CQ and HCQ in COVID-19 has yet to be proven with randomized controlled studies, many of which are currently ongoing, also considering pharmacokinetics, optimal dosing regimen, therapeutic level and duration of treatment and taking into account patients with different severity degrees of disease. Here we review what is currently known on the mechanisms of action of CQ and HCQ as anti-viral, anti-inflammatory and anti-thrombotic drugs and discuss the up-to-date experimental evidence on the potential mechanisms of action of CQ/HCQ in Sars-Cov2 infection and the current clinical knowledge on their efficacy in the treatment of COVID-19 patients. Given the role of iron in several human viral infections, we also propose a different insight into a number of CQ and HCQ pharmacological effects, suggesting a potential involvement of iron homeostasis in Sars-Cov-2 infection and COVID-19 clinical course.

Biologics in the treatment of pustular psoriasis

INTRODUCTION

Pustular psoriasis is a group of skin diseases characterized by neutrophil infiltration in the epidermis and formation of sterile pustules. Conventional treatments, such as retinoids and immunosuppressive drugs, have improved the clinical manifestations; however, many patients suffer from drug-related toxicity or are resistant to therapy.

AREAS COVERED

In this review, the authors focus on the efficacy and safety of these biologics, including anti-IL-1β (gevokizumab and canakinumab), anti-IL-1 R (anakinra), anti-IL-36 R (BI 655130), anti-tumor necrosis factor-α (etanercept, infliximab, and adalimumab), anti-IL-12/23 (ustekinumab), anti-IL-17A (secukinumab and ixekizumab), anti-IL-17RA (brodalumab), anti-IL-2 R (basiliximab), anti-IL-6 R (tocilizumab), and anti-IL-23 (risankizumab and guselkumab), for treating pustular psoriasis.

EXPERT OPINION

Patients with pustular psoriasis treated with biologics demonstrated positive responses. Anti-TNF-α is the most available biologics for the treatment of pustular psoriasis, and anti-IL-12/23 and anti-IL-17A might be considered as the first- or second-line therapy for moderate-to-severe and refractory pustular psoriasis. Anti-IL-17A can be used in the pustular psoriasis patients who failed to respond to anti-TNF agents and anti-IL-12/23. Therapeutic efficacy of biologics in pustular psoriasis might have no association with IL-36 RN mutation status.

Inflammatory Bowel Disease in the COVID-19 Pandemic: the Patients' Perspective

BACKGROUND

The coronavirus disease 2019 [COVID-19] pandemic is affecting lives worldwide. The influence of inflammatory bowel disease [IBD] medication and IBD itself on COVID-19 is controversial. Additionally, IBD-focused guidance is scarce.

OBJECTIVE

Our aims were to determine COVID-19 prevalence/exposure, perception and information sources, medication compliance, patient behaviour and physician contact among patients with IBD compared with non-IBD controls.

METHODS

A cross-sectional anonymous survey of patients with IBD [N = 415] at one university IBD clinic and one gastroenterology practice, matched 4:1 with control participants [N = 116], was performed.

RESULTS

Patients with IBD had a high fear of infection. This was more pronounced in patients taking immunosuppressants and it extended to hospitals, private practices and public places, such as supermarkets. IBD patients reported leaving their homes less frequently than their peers without IBD. A total of 90% of patients with IBD reported washing their hands more frequently. Patients taking immunosuppressants were concerned about interactions between medication and COVID-19, whereas patients taking 5-aminosalicylates were not. Nonetheless, 96.4% of patients adhered to continuing their medication. Patients sought guidance primarily from television and internet news sites. Video consultations were found to be a suitable solution for a subset of patients who are young, have a high level of fear and leave their home less frequently than their peers, whereas overall acceptance of video consultations was limited.

CONCLUSION

Patients with IBD are significantly more affected by the COVID-19 pandemic than their non-IBD peers, but they continue to adhere to their medication regimens. IBD-focused COVID-19 information should be actively conveyed.

ZJ01, a Small Molecule Inhibitor of the Kelch-Like ECH-Associated Protein 1-Nuclear Factor Erythroid 2-Related Factor 2 (Keap1-Nrf2) Protein-Protein Interaction, Reduces Hyperoxic Acute Lung Injury in a Mouse Model

Background

Hyperoxic acute lung injury (ALI) is a complication of ventilation in patients with respiratory failure. Nuclear factor erythroid-2-related factor 2 (Nrf2) has an important role in ALI. Kelch-like ECH-associated protein 1 (Keap1) binds to Nrf2. ZJ01 is a small molecule inhibitor of Keap1-Nrf2 protein-protein interaction (PPI) that can reduce Keap1-induced inhibition of Nrf2. This study aimed to investigate the effects of ZJ01 and the heme oxygenase-1 (HO-1) inhibitor, zinc protoporphyrin IX (ZnPP IX), in a mouse model of hyperoxic ALI.

Material/Methods

C57BL/6J mice included five study groups: the room air+vehicle-treated group; the room air+ZJ01 group; the hyperoxia+vehicle-treated group; the hyperoxia+ZJ01 group; and the hyperoxia+ZJ01+ZnPP IX group. ZJ01, ZnPP IX, or vehicle were given 1 h after the hyperoxia challenge. The lungs from the mice were harvested at 72 h following the hyperoxia challenge.

Results

Hyperoxia exposure for 72 h increased the activity of myeloperoxidase, the lung water content, the levels of tumor necrosis factor-α (TNF-α), and matrix metalloprotease-9 (MMP-9) in the vehicle-treated mice. ZJ01 treatment reduced hyperoxia-induced inflammation and increased the activation of Nrf2 and HO-1 compared with the vehicle-treated mice. Histology of the lungs showed that ZJ01 treatment reduced the changes of hyperoxia-induced ALI. Pretreatment with ZnPP IX reversed the beneficial effect of ZJ01.

Conclusions

ZJ01, a Keap1-Nrf2 PPI inhibitor, reduced hyperoxic ALI in a mouse model through the Nrf2/HO-1 pathway.

TNFα and IL-17 alkalinize airway surface liquid through CFTR and pendrin

The pH of airway surface liquid (ASL) is a key factor that determines respiratory host defense; ASL acidification impairs and alkalinization enhances key defense mechanisms. Under healthy conditions, airway epithelia secrete base ([Formula: see text]) and acid (H⁺) to control ASL pH (pH_ASL). Neutrophil-predominant inflammation is a hallmark of several airway diseases, and TNFα and IL-17 are key drivers. However, how these cytokines perturb pH_ASL regulation is uncertain. In primary cultures of differentiated human airway epithelia, TNFα decreased and IL-17 did not change pH_ASL. However, the combination (TNFα+IL-17) markedly increased pH_ASL by increasing [Formula: see text] secretion. TNFα+IL-17 increased expression and function of two apical [Formula: see text] transporters, CFTR anion channels and pendrin Cl^-/[Formula: see text] exchangers. Both were required for maximal alkalinization. TNFα+IL-17 induced pendrin expression primarily in secretory cells where it was coexpressed with CFTR. Interestingly, significant pendrin expression was not detected in CFTR-rich ionocytes. These results indicate that TNFα+IL-17 stimulate [Formula: see text] secretion via CFTR and pendrin to alkalinize ASL, which may represent an important defense mechanism in inflamed airways.

Effects of PDE3 Inhibitor Olprinone on the Respiratory Parameters, Inflammation, and Apoptosis in an Experimental Model of Acute Respiratory Distress Syndrome

This study aimed to investigate whether a selective phosphodiesterase-3 (PDE3) inhibitor olprinone can positively influence the inflammation, apoptosis, and respiratory parameters in animals with acute respiratory distress syndrome (ARDS) model induced by repetitive saline lung lavage. Adult rabbits were divided into 3 groups: ARDS without therapy (ARDS), ARDS treated with olprinone i.v. (1 mg/kg; ARDS/PDE3), and healthy ventilated controls (Control), and were oxygen-ventilated for the following 4 h. Dynamic lung-thorax compliance (Cdyn), mean airway pressure (MAP), arterial oxygen saturation (SaO2), alveolar-arterial gradient (AAG), ratio between partial pressure of oxygen in arterial blood to a fraction of inspired oxygen (PaO2/FiO2), oxygenation index (OI), and ventilation efficiency index (VEI) were evaluated every hour. Post mortem, inflammatory and oxidative markers (interleukin (IL)-6, IL-1β, a receptor for advanced glycation end products (RAGE), IL-10, total antioxidant capacity (TAC), 3-nitrotyrosine (3NT), and malondialdehyde (MDA) and apoptosis (apoptotic index and caspase-3) were assessed in the lung tissue. Treatment with olprinone reduced the release of inflammatory mediators and markers of oxidative damage decreased apoptosis of epithelial cells and improved respiratory parameters. The results indicate a future potential of PDE3 inhibitors also in the therapy of ARDS.

The Society for Immunotherapy of Cancer perspective on regulation of interleukin-6 signaling in COVID-19-related systemic inflammatory response

The pandemic caused by the novel coronavirus SARS-CoV-2 has placed an unprecedented burden on healthcare systems around the world. In patients who experience severe disease, acute respiratory distress is often accompanied by a pathological immune reaction, sometimes referred to as 'cytokine storm'. One hallmark feature of the profound inflammatory state seen in patients with COVID-19 who succumb to pneumonia and hypoxia is marked elevation of serum cytokines, especially interferon gamma, tumor necrosis factor alpha, interleukin 17 (IL-17), interleukin 8 (IL-8) and interleukin 6 (IL-6). Initial experience from the outbreaks in Italy, China and the USA has anecdotally demonstrated improved outcomes for critically ill patients with COVID-19 with the administration of cytokine-modulatory therapies, especially anti-IL-6 agents. Although ongoing trials are investigating anti-IL-6 therapies, access to these therapies is a concern, especially as the numbers of cases worldwide continue to climb. An immunology-informed approach may help identify alternative agents to modulate the pathological inflammation seen in patients with COVID-19. Drawing on extensive experience administering these and other immune-modulating therapies, the Society for Immunotherapy of Cancer offers this perspective on potential alternatives to anti-IL-6 that may also warrant consideration for management of the systemic inflammatory response and pulmonary compromise that can be seen in patients with severe COVID-19.

Increased mortality of acute respiratory distress syndrome was associated with high levels of plasma phenylalanine

Background

There is a dearth of drug therapies available for the treatment of acute respiratory distress syndrome (ARDS). Certain metabolites play a key role in ARDS and could serve as potential targets for developing therapies against this respiratory disorder. The present study was designed to determine such “functional metabolites” in ARDS using metabolomics and in vivo experiments in a mouse model.

Methods

Metabolomic profiles of blood plasma from 42 ARDS patients and 28 healthy controls were captured using Ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) assay. Univariate and multivariate statistical analysis were performed on metabolomic profiles from blood plasma of ARDS patients and healthy controls to screen for “functional metabolites”, which were determined by variable importance in projection (VIP) scores and P value. Pathway analysis of all the metabolites was performed. The mouse model of ARDS was established to investigate the role of “functional metabolites” in the lung injury and mortality caused by the respiratory disorder.

Results

The metabolomic profiles of patients with ARDS were significantly different from healthy controls, difference was also observed between metabolomic profiles of the non-survivors and the survivors among the ARDS patient pool. Levels of Phenylalanine, D-Phenylalanine and Phenylacetylglutamine were significantly increased in non-survivors compared to the survivors of ARDS. Phenylalanine metabolism was the most notably altered pathway between the non-survivors and survivors of ARDS patients. In vivo animal experiments demonstrated that high levels of Phenylalanine might be associated with the severer lung injury and increased mortality of ARDS.

Conclusion

Increased mortality of acute respiratory distress syndrome was associated with high levels of plasma Phenylalanine.

Trial registration

Chinese Clinical Trial Registry, ChiCTR1800015930. Registered 29 April 2018, http://www.chictr.org.cn/edit.aspx?pid=25609&htm=4

Effects of icariin on cell injury and glucocorticoid resistance in BEAS-2B cells exposed to cigarette smoke extract

Glucocorticoids (GCs) exert a therapeutic effect in numerous chronic inflammatory diseases. However, chronic obstructive pulmonary disease (COPD) tends to be GC-resistant. Icariin, a major component of flavonoids isolated from Epimedium brevicornum Maxim (Berberidaceae), significantly relieves symptoms in patients with COPD. However, the mechanism of action remains unclear and further investigation is required to establish whether it may serve as an alternative or complementary therapy for COPD. The aim of the present study was to determine the effects of icariin in human bronchial epithelial cells exposed to cigarette smoke extract (CSE) and to determine whether icariin reverses GC resistance. The results revealed that icariin significantly increased the proliferation of CSE-exposed cells. Furthermore, icariin significantly increased protein expression of the anti-inflammatory factor interleukin (IL)-10 and significantly decreased protein expression of the pro-inflammatory factors IL-8 and tumor necrosis factor α. Icariin also attenuated the expression of the cellular matrix remodelling biomarkers matrix metallopeptidase 9 and tissue inhibitor of metalloproteinase 1, and decreased the production of reactive oxygen species (ROS). In addition, icariin regulated the expression of GC resistance-related factors, such as GC receptors, histone deacetylase 2, nuclear factor erythroid-2-related factor 2 and nuclear factor κ B. The results obtained in the present study suggested that icariin may decrease CSE-induced inflammation, airway remodelling and ROS production by mitigating GC resistance. In conclusion, icariin may potentially be used in combination with GCs to increase therapeutic efficacy and reduce GC resistance in COPD.

Pro-inflammatory effects of crystalline- and nano-sized non-crystalline silica particles in a 3D alveolar model

BACKGROUND

Silica nanoparticles (SiNPs) are among the most widely manufactured and used nanoparticles. Concerns about potential health effects of SiNPs have therefore risen. Using a 3D tri-culture model of the alveolar lung barrier we examined effects of exposure to SiNPs (Si10) and crystalline silica (quartz; Min-U-Sil) in the apical compartment consisting of human alveolar epithelial A549 cells and THP-1-derived macrophages, as well as in the basolateral compartment with Ea.hy926 endothelial cells. Inflammation-related responses were measured by ELISA and gene expression.

RESULTS

Exposure to both Si10 and Min-U-Sil induced gene expression and release of CXCL8, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1α (IL-1α) and interleukin-1β (IL-1β) in a concentration-dependent manner. Cytokine/chemokine expression and protein levels were highest in the apical compartment. Si10 and Min-U-Sil also induced expression of adhesion molecules ICAM-1 and E-selectin in the apical compartment. In the basolateral endothelial compartment we observed marked, but postponed effects on expression of all these genes, but only at the highest particle concentrations. Geneexpressions of heme oxygenase-1 (HO-1) and the metalloproteases (MMP-1 and MMP-9) were less affected. The IL-1 receptor antagonist (IL-1RA), markedly reduced effects of Si10 and Min-U-Sil exposures on gene expression of cytokines and adhesion molecules, as well as cytokine-release in both compartments.

CONCLUSIONS

Si10 and Min-U-Sil induced gene expression and release of pro-inflammatory cytokines/adhesion molecules at both the epithelial/macrophage and endothelial side of a 3D tri-culture. Responses in the basolateral endothelial cells were only induced at high concentrations, and seemed to be mediated by IL-1α/β released from the apical epithelial cells and macrophages.

Sesamol Alleviates Airway Hyperresponsiveness and Oxidative Stress in Asthmatic Mice

Sesamol, isolated from sesame seeds (Sesamum indicum), was previously shown to have antioxidative, anti-inflammatory, and anti-tumor effects. Sesamol also inhibited lipopolysaccharide (LPS)-induced pulmonary inflammatory response in rats. However, it remains unclear how sesamol regulates airway inflammation and oxidative stress in asthmatic mice. This study aimed to investigate the efficacy of sesamol on oxidative stress and airway inflammation in asthmatic mice and tracheal epithelial cells. BALB/c mice were sensitized with ovalbumin, and received oral sesamol on days 14 to 27. Furthermore, BEAS-2B human bronchial epithelial cells were treated with sesamol to investigate inflammatory cytokine levels and oxidative responses in vitro. Our results demonstrated that oral sesamol administration significantly suppressed eosinophil infiltration in the lung, airway hyperresponsiveness, and T helper 2 cell-associated (Th2) cytokine expressions in bronchoalveolar lavage fluid and the lungs. Sesamol also significantly increased glutathione expression and reduced malondialdehyde levels in the lungs of asthmatic mice. We also found that sesamol significantly reduced proinflammatory cytokine levels and eotaxin in inflammatory BEAS-2B cells. Moreover, sesamol alleviated reactive oxygen species formation, and suppressed intercellular cell adhesion molecule-1 (ICAM-1) expression, which reduced monocyte cell adherence. We demonstrated that sesamol showed potential as a therapeutic agent for improving asthma.

Necrostatin‑1 protects mice from acute lung injury by suppressing necroptosis and reactive oxygen species

Acute lung injury (ALI) is characterized by tissue damage and inflammatory cytokine secretion; however, the therapeutic options available to treat ALI remain limited. Necrostatin-1 (Nec-1) has the ability to attenuate cell necroptosis in various inflammatory diseases. The present study evaluated the protective effects of Nec-1 on a mouse model of lipopolysaccharide-induced ALI. Histological alterations in the lungs were evaluated through hematoxylin and eosin staining, and the expression levels of cytokines in the bronchoalveolar lavage fluid and lung tissues were determined by ELISA. In addition, accumulated production of reactive oxygen species was determined by staining with DCFH-DA probes, western blotting and immunofluorescence. The results revealed that treatment with the necroptosis inhibitor, Nec-1, exerted significant protective effects on ALI-induced inflammation and necroptosis. The key proteins involved in necroptosis were markedly reduced, including receptor-interacting serine/threonine-protein kinase (RIP)1 and RIP3. Notably, antioxidant proteins were upregulated by Nec-1, which may attenuate oxidative stress. Furthermore, treatment with Nec-1 markedly suppressed necroptosis in the pulmonary alveoli RLE-6TN cell line. Taken together, these data revealed a novel association between ALI and necroptosis, and suggested that necroptosis inhibitors may be used as effective anti-inflammatory drugs to treat ALI.

Amphiregulin inhibits TNF-α-induced alveolar epithelial cell death through EGFR signaling pathway

BACKGROUND

We previously observed that amphiregulin (Areg), a ligand of epithelial growth factor receptor (EGFR), was highly expressed in lipopolysaccharide (LPS)-induced acute lung injury (ALI) lung tissues mainly by the classically activated (M1) alveolar macrophages (AMs). Areg also plays a protective role in LPS-induced injury in lung tissues and alveolar epithelial cells (AECs). However, whether Areg is co-expressed with tumor necrosis factor (TNF)-α in ALI lung tissues, and can directly inhibit TNF-α-induced AEC injury remains unclear.

METHODS

We first detected the kinetic expressions of Areg and TNF-α in LPS-stimulated lung tissues and M1 AMs and then identified the role of exogenous recombinant Areg (rmAreg) in the injured lung tissues. The effect of Areg on TNF-α-induced apoptosis in MLE-12 cells, a kind of AECs, was examined by terminal deoxynucleotidyl transferase dUTP nick end labeling staining. The activation of the EGFR-AKT pathway and caspase-3, -8, and -9 were detected by Western blotting. The EGFR knockdown by small interfering RNA was used to assess the role of EGFR in Areg functions.

RESULTS

Areg production occurred in close parallel with TNF-α expression in M1 AMs and ALI lung tissues, and rmAreg attenuated LPS-induced ALI in mice. TNF-α stimulation induced significant apoptosis in MLE-12 cells, but this apoptosis was inhibited under rmAreg treatment. Moreover, rmAreg enhanced the activation of EGFR and AKT, and reduced the expressions of cleaved caspase-3, -8, and -9 in ALI lung tissues and TNF-α-challenged MLE-12 cells. However, the EGFR knockdown significantly inhibited the Areg-induced improvement in apoptosis, enhancement of EGFR and AKT activation, and reduction of cleaved caspase-3, -8, and -9 expressions.

CONCLUSIONS

Areg and TNF-α were synchronously produced by ALI lung tissues and M1 AMs, and Areg directly inhibited the TNF-induced apoptosis and transduction of caspase death signals in AECs via the EGFR pathway.

The protective effects of Thalictrum minus L. on lipopolysaccharide-induced acute lung injury

ETHNOPHARMACOLOGICAL RELEVANCE

Thalictrum minus L., a Mongolian folk medicinal plant, was applied for the treatment of bacterial and fungal infection, tuberculosis and lung inflammation.

AIM OF THE STUDY

The present work aims to elucidate the protective effects of Thalictrum minus L.(TML) against lipopolysaccharide (LPS)-induced acute lung injury and the underlying mechanisms.

METHODS

The mice model of acute lung injury was induced by LPS via endotracheal drip, and TML (10, 20, 40 mg/kg) were administered orally 1 h prior to LPS. The efficacy and molecular mechanisms in the presence or absence of TML were investigated.

RESULTS

We demonstrated that treatment with TML aqueous extract protected the mice from acute lung injury induced by LPS administration. TML significantly inhibited weight loss in mice, decreased the lung wet to dry weight (W/D) ratios and attenuated lung histopathological changes, such as infiltration of inflammatory cells and coagulation, pulmonary edema. Furthermore, we found that TML markedly reduced the LPS-induced inflammatory cytokines including tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), decreased nitric oxide (NO), and increased superoxide dismutase (SOD) in bronchoalveolar lavage fluid (BALF), and effectively ameliorated LPS-induced increased total protein, leukocyte and macrophages in BALF. In addition, TML pronouncedly suppressed the activation of the MAPKs p38-NLRP3/caspase-1 and COX2, increased the expression of p-AMPK-Nrf2, and suppressed the expression of KEAP, apoptotic-related protein as well as autophagy.

CONCLUSIONS

These results suggested that TML ameliorated LPS-induced acute lung injury by inhibiting the release of inflammatory cytokines and reducing oxidative damage associated with the MAPKs p38-NLRP3/caspase-1 and COX2 signaling pathways, AMPK-Nrf2/KEAP signaling pathways, as well as apoptosis and autophagy.

An inflammatory stimulus sensitizes TRPA1 channel to increase cytokine release in human lung fibroblasts

External stimuli such as cigarette smoke and house dust mite are often involved in the development and exacerbation of asthma. These risk factors could activate or sensitize transient receptor potential channel ankyrin 1 (TRPA1), which are primarily expressed in neuronal structures but also in non-neuronal cells such as fibroblasts. However, the role of non-neuronal TRPA1 in the pathophysiology of airway diseases including asthma remains unclear. We investigated TRPA1 expression on human fibroblast cells and whether inflammatory mediators could modulate its function. This study utilized human lung fibroblast cell lines, Medical Research Council cell strain 5 (MRC-5) and HF19 cells frequently used on experimental studies regarding allergic and respiratory disorders. The human lung fibroblasts were stimulated with house dust mite (Der p1) or tumor necrosis factor alpha (TNF-α) for 24 h, and we quantified TRPA1 mRNA and protein by qRT-PCR and western blot analysis, respectively. TRPA1 mRNA expressions were upregulated after TNF-α treatment. Calcium imaging analysis revealed that TNF-α treatment apparently sensitized TRPA1-mediated calcium influx by TRPA1 agonist allyl isothiocyanate (AITC) and the selective TRPA1 channel blocker HC-030031 effectively reduced the calcium response. Lastly, TRPA1 activation was not only involved in increased IL-8 cytokine release, but also in upregulating gene expression of matrix metalloprotease 9 (MMP9) in the human lung fibroblasts treated with TNF-α Together, these results indicate that presence of inflammatory mediators such as TNF-α could upregulate the non-neuronal expression of TRPA1 on fibroblasts which may aggravate further the release of inflammatory cytokines observed in human airway diseases.

Acute 1-NP exposure induces inflammatory responses through activating various inflammatory signaling pathways in mouse lungs and human A549 cells

1-Nitropyrene (1-NP), a key component of fine particulate matter (PM2.5), is a representative of nitrated polycyclic aromatic hydrocarbons (NPAHs). The aim of this research is to investigate proinflammatory effects of acute 1-NP exposure in mouse lungs and human A549 cells. All mice except controls were intratracheally instilled with 1-NP (20 μg/mouse). A549 cell, a human lung cancer cell line, was cultured with or without 1-NP (5 μM). Acute 1-NP exposure elevated lung weight and caused infiltration of inflammatory cells, especially neutrophils in mouse lungs. Although it had little effect on serum TNF-α and KC, acute 1-NP exposure elevated the levels of TNF-α and KC in BALF. Correspondingly, acute 1-NP exposure upregulated pulmonary Il-1β, Il-6, Tnf-α and Kc. Mechanistically, acute 1-NP exposure activated nuclear factor kappa B (NF-κB) in mouse lungs and human A549 cells. Additionally, acute 1-NP exposure induced Akt phosphorylation in mouse lungs and human A549 cells. Moreover, acute 1-NP exposure induced phosphorylation of pulmonary JNK and ERK1/2, molecules of the mitogen-activated protein kinase (MAPK) pathway. This study provides evidence that acute 1-NP exposure induces inflammatory responses through activating various inflammatory signaling pathways in mouse lungs and human A549 cells.

Induction of HO-1 by Mevastatin Mediated via a Nox/ROS-Dependent c-Src/PDGFRα/PI3K/Akt/Nrf2/ARE Cascade Suppresses TNF-α-Induced Lung Inflammation

Background: Mevastatin (MVS), a 3-hydroxy-3-methylglutaryl coenzyme, a reductase (HMG-CoA) inhibitor, has anti-inflammatory effects potentially via up-regulation of heme oxygenase-1 (HO-1). However, the mechanisms underlying MVS-induced HO-1 expression remain largely unknown in human pulmonary alveolar epithelial cells (HPAEpiCs). Methods: HO-1 and intercellular adhesion molecule (ICAM)-1 expression were determined using real-time PCR, Western blotting, and promoter reporter analyses. The signaling components were investigated using pharmacological inhibitors or specific small interfering RNA (siRNA)s. Interaction between Nrf2 and the antioxidant response element (ARE) binding site for the HO-1 promoter was determined by chromatin immunoprecipitation (ChIP) assay. Results: Upregulation of HO-1 by MVS attenuated the tumor necrosis factor (TNF)-α-stimulated ICAM-1 expression associated with THP-1 adhesion to HPAEpiCs. These inhibitory effects of HO-1 were reversed by tin protoporphyrin (SnPP)IX or by transfection with HO-1 siRNA. MVS-induced HO-1 expression was mediated via NADPH oxidase (Nox)-derived reactive oxygen species (ROS) generation. Activation of Nox2/ROS further stimulated the phosphorylation of p47^phox, proto-oncogene tyrosine-protein kinase (c-Src), platelet-derived growth factor receptor (PDFGR)α, protein kinase B (Akt), and Nrf2, which were inhibited by siRNAs. Pretreatment with pharmacological inhibitors, including diphenyleneiodonium (DPI), apocynin (APO), N-acetyl-L-cysteine (NAC), PP1, AG1296, or LY294002, reduced the MVS-activated Nrf2 nuclear-translocation binding to the ARE on the HO-1 promoter. Conclusions: MVS-induced HO-1 is, at least in part, mediated through a p47^phox/Nox2/ROS-dependent activation of c-Src/PDGFRα/PI3K/Akt-regulated Nrf2/ARE axis and suppresses the TNF-α-mediated inflammatory responses in HPAEpiCs.

Decreased secretion of tumor necrosis factor-α attenuates macrophages-induced insulin resistance in skeletal muscle

AIMS

Macrophages, as an important member of immune system, engulf and digest pathogens in innate immunity and help initiate adaptive immunity. However, macrophages also involve in occurrence and development of many diseases, such as obesity and type 2 diabetes. Here, we aimed to reveal how activated macrophages cause insulin resistance in skeletal muscle in vitro through simulating body environment.

MAIN METHODS

We established RAW264.7 macrophages and C2C12 myotubes co-incubation model in vitro using Transwell filter to simulate body environment and investigated effects of RAW264.7 cells on insulin-regulated glucose metabolism in C2C12 myotubes. Immunofluorescence, Immunoblot and glucose uptake tests were used to assess metabolic changes in C2C12 myotubes. ELISA test detected secretions of tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) from RAW264.7 cells. In addition, RNA interference and inhibitor treatment were used.

KEY FINDINGS

Activated RAW264.7 cells attenuated insulin response in C2C12 myotubes. Activated RAW264.7 cells secreted a lot of TNF-α and IL-6. We found that TNFα, but not IL-6, caused insulin resistance of skeletal muscle in a dose-dependent manner. The results further indicated that activation of TNF-α downstream proteins, inhibitor of nuclear factor κ-B kinase (IKK) and the jun-N-terminal kinase 1 (JNK1) led to phosphorylation of insulin receptor substrate 1 (IRS-1) at Ser residues and insulin resistance in C2C12 myotubes.

SIGNIFICANCE

Our research provided further and direct demonstration on activated macrophage-induced insulin resistance in skeletal muscle, suggesting TNF-α might become a therapeutic target to ameliorate and treat type 2 diabetes.

Point-of-Care Ultrasound-A New Option for Early Quantitative Assessment of Pulmonary Edema

The aim of the work described here was to investigate the value of point-of-care ultrasound (POCUS) in the early assessment of the severity of pulmonary edema in rabbits. A rabbit oleic acid (OA)-induced pulmonary edema model was used. Thirty-two New Zealand rabbits were randomly divided into four groups: a control group and three pulmonary edema groups (mild, moderate and severe). Features of transthoracic B-line artifacts (BLA), blood pH, PaO₂ and PaCO₂, serum inflammatory factors, lung coefficient (LC), lung wet-to-dry weight ratio (W/D) and lung histopathology were assessed. BLA features and severity of pulmonary edema were semiquantitatively scored. Correlations between the number of BLA and PaO₂, PaCO₂, serum inflammatory factors, LC and W/D were analyzed. An additional 8 rabbits with severe pulmonary edema were used as the verified group, in which the lung was divided into ex vivo BLA (BLA-ev)-free (BLA-ev-free) and BLA-ev-clustered subregions depending on the features of BLA-ev recorded by ex vivo lung ultrasound. Lung specimens from each subregion were collected for histopathological examination. Relationships between features of BLA-ev and lung histopathological abnormalities were analyzed. With increasing doses of OA, number of BLA, W/D and levels of serum inflammatory factors decreased. Meanwhile, lung pathologic abnormalities were aggravated. In addition, time of appearance of BLA, blood pH and PaO_2, and PaCO₂ decreased dose dependently on OA (p < 0.05). Number of BLA was linear positively correlated with severity of pulmonary edema (r = 0.953, p < 0.05). Consistently, the features of BLA-ev reflected the severity of lung histopathological abnormalities (r = 0.936, p < 0.05). Thus, POCUS is useful in the early quantitative assessment of the severity of pulmonary edema.

TNFR2 Signaling Enhances ILC2 Survival, Function, and Induction of Airway Hyperreactivity

Group 2 innate lymphoid cells (ILC2s) can initiate pathologic inflammation in allergic asthma by secreting copious amounts of type 2 cytokines, promoting lung eosinophilia and airway hyperreactivity (AHR), a cardinal feature of asthma. We discovered that the TNF/TNFR2 axis is a central immune checkpoint in murine and human ILC2s. ILC2s selectively express TNFR2, and blocking the TNF/TNFR2 axis inhibits survival and cytokine production and reduces ILC2-dependent AHR. The mechanism of action of TNFR2 in ILC2s is through the non-canonical NF-κB pathway as an NF-κB-inducing kinase (NIK) inhibitor blocks the costimulatory effect of TNF-α. Similarly, human ILC2s selectively express TNFR2, and using hILC2s, we show that TNFR2 engagement promotes AHR through a NIK-dependent pathway in alymphoid murine recipients. These findings highlight the role of the TNF/TNFR2 axis in pulmonary ILC2s, suggesting that targeting TNFR2 or relevant signaling is a different strategy for treating patients with ILC2-dependent asthma.

Hydroxysafflor Yellow A Inhibits TNF-α-Induced Inflammation of Human Fetal Lung Fibroblasts via NF-κB Signaling Pathway

Objective

Hydroxysafflor yellow A (HSYA), an effective ingredient of the Chinese herb Carthamus tinctorius L, attenuated bleomycin-induced pulmonary fibrosis in mice. This study is to investigate the effect of HSYA on the proliferation and inflammatory level of human fetal lung fibroblasts (MRC-5 cells) induced by tumor necrosis factor-α (TNF-α) and explore the underlying mechanisms.

Methods

MRC-5 cells were treated with different concentrations of TNF-α, HSYA, or/and etanercept (ENCP, TNF-α receptor (TNFR1) antagonist, 500 ng/mL) before cell proliferation was detected. The laser confocal microscope was used to observe the role of HSYA in binding of TNF-α and its receptor. Co-immunoprecipitation was used to detect the binding of TNFR1 and TAK1-TAB2 complex. Real-time quantitative RT-PCR and western blot were used to detect the expressions of inflammation-related cytokines and proteins related with the NF-κB pathway. Luciferase reporter gene assay and chromatin coprecipitation method were used to detect the interaction between AP-1 and TGF-β1 promoter.

Results

TNF-α (5 ng/mL) was used to induce inflammation and proliferation in MRC-5 cells. HSYA can partially suppress the stimulation of TNF-α on proliferation and inflammatory response of MRC-5 cells. HSYA could compete with TNF-α to bind with TNFR1 and hamper the binding of TNFR1 to TAK1-TAB2 complex. In addition, HSYA could also inhibit the activation of the NF-κB signal pathway and suppress the binding of TGF-β1 promoter with AP-1.

Conclusion

Evidence in this study suggested that HSYA affects TNF-α-induced proliferation and inflammatory response of MRC-5 cells through the NF-κB/AP-1 signaling pathway, which may provide theoretical basis for HSYA treatment in pulmonary fibrosis.

Design, synthesis and biological evaluation of novel desloratadine derivatives with anti-inflammatory and H1 antagonize activities

To improve the anti-inflammatory activity of desloratadine, we designed and synthesized a series of novel desloratadine derivatives. All compounds were evaluated for their anti-inflammatory and H₁ antagonistic activities. Among them, compound 2c showed the strongest H₁ antagonistic and anti-inflammatory activity. It also exhibited promising pharmacokinetic profiles and low toxicity. All these results suggest that compound 2c as a novel anti-allergic agent is worthy of further investigation.

Protective effects of GHK-Cu in bleomycin-induced pulmonary fibrosis via anti-oxidative stress and anti-inflammation pathways

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a serious lung problem with advancing and diffusive pulmonary fibrosis as the pathologic basis, and with oxidative stress and inflammation as the key pathogenesis. Glycyl-L-histidyl-l-lysine (GHK) is a tripeptide participating into wound healing and regeneration. GHK-Cu complexes improve GHK bioavailability. Thus, the current study aimed to explore the therapeutic role of GHK-Cu on bleomycin (BLM)-induced pulmonary fibrosis in a mouse model.

METHODS

BLM (3 mg/kg) was administered via tracheal instillation (TI) to induce a pulmonary fibrosis model in C57BL/6j mice 21 days after the challenge of BLM. GHK-Cu was injected intraperitoneally (i.p.) at different dosage of 0.2, 2 and 20 μg/g/day in 0.5 ml PBS on alternate day. The histological changes, inflammation response, the collagen deposition and epithelial-mesenchymal transition (EMT) was evaluated in the lung tissue. EMT was evaluated by ɑ-SMA and fibronectin expression in the lung tissue. NF-κB p65, Nrf2 and TGFβ1/Smad2/3 signalling pathways were detected by immunoblotting analysis.

RESULTS

GHK-Cu complex inhibited BLM-induced inflammatory and fibrotic pathological changes, alleviated the inflammatory response in the BALF by reducing the levels of the inflammatory cytokines, TNF-ɑ and IL-6 and the activity of MPO as well as reduced collagen deposition. In addition, the GHK-Cu treatment significantly reversed the MMP-9/TIMP-1 imbalance and partially prevented EMT via Nrf2, NF-κB and TGFβ1 pathways, as well as Smad2/3 phosphorylation.

CONCLUSIONS

GHK-Cu presented a protective effect in BLM-induced inflammation and oxidative stress by inhibiting EMT progression and suppressing TGFβ1/Smad2/3 signalling in pulmonary fibrosis.

Cytokine signatures associate with disease severity in children with Mycoplasma pneumoniae pneumonia

Host immune response may be involved in the pathogenesis of children Mycoplasma pneumoniae pneumonia (MPP). In the current study, we investigated the alterations of cytokines levels among control, mild MPP and severe MPP children to determine whether cytokine signatures associate with MPP and correlate with disease severity. We measured 13 cytokines in bronchoalveolar lavage fluid (BALF) of 88 children with MPP and 26 children with foreign body aspiration (FB) using a Luminex system. Linear discriminant analyses were performed to develop predictive models of mild MPP and severe MPP on these children. We observed nearly complete separations of severe MPP group, mild MPP group and control group in linear discriminant analyses. Eleven cytokines significantly increased in children with MPP, and seven cytokines had statistically significant upward linear trends correlated with MPP severity. In addition, compared to control group, both IFNγ/IL4 ratio and IFNγ/IL13 ratio increased in mild MPP and severe MPP groups. Our results suggest that children MPP can alter BALF cytokines signatures which associate with disease severity and can be characterized by a distinct airway molecular phenotype that has elevated Th1/Th2 ratios.

Baicalein attenuates OVA-induced allergic airway inflammation through the inhibition of the NF-κB signaling pathway

Asthma is a type of chronic lung inflammation with restrictions in effective therapy. NF-κB pathway activation has been suggested to play an important role in the pathogenesis of asthma. Baicalein, one of the major active flavonoids found in Scutellaria baicalensis, exhibits potent anti-inflammatory properties by inhibiting NF-κB activity. Herein, we report that Baicalein significantly reduces OVA-induced airway hyperresponsiveness (AHR), airway inflammation, serum IgE levels, mucus production, and collagen deposition around the airway. Additionally, western blot analysis and immunofluorescence assay showed that Baicalein attenuates the activation of NF-κB, which was mainly reflected by IκBα phosphorylation and degradation, p65 nuclear translocation and downstream iNOS expression. Furthermore, in human epithelial cells, Baicalein blocked TNF-α-induced NF-κB activation. Our study provides evidence that Baicalein administration alleviates the pathological changes in asthma through inactivating the NF-κB/iNOS pathway. Baicalein might be a promising potential therapy agent for patients with allergic asthma in the future.

Pharmacodynamics OF TNF α inhibitors for the treatment of psoriasis

Introduction: The treatment of psoriasis with conventional topical therapies and disease-modifying anti-rheumatic drugs (DMARDs) is often linked to unsatisfactory outcomes and the risk of serious adverse events. Over the last decades, research advances in understanding the role of tumor necrosis factor alpha (TNF α) and other cytokines in the pathogenesis of psoriasis have driven the introduction of biologic agents targeting specific immune mediators in everyday clinical practice. TNF α inhibitors are a consolidated treatment option for patients with moderate-to-severe disease with remarkable efficacy and a reassuring safety profile.Areas covered: The PubMed database was searched using combinations of the following keywords: psoriasis, TNF α inhibitors, biologic therapy, pharmacodynamics, adalimumab, etanercept, infliximab, certolizumab pegol, golimumab, adverse effects. The aim of this review is to describe the pharmacodynamic profile of anti-TNF α inhibitors, currently approved by the European Medicines Agency (EMA) for the treatment of psoriasis, focusing on related clinical implications, also in comparison to the new generation biological therapies targeting the interleukin 23/interleukin 17 axis.Expert opinion: Pharmacodynamics of TNF α inhibitors should be fully considered in planning patient's therapy strategies, especially in case of secondary failures, poor adherence to treatment, instable psoriasis, high risk of infection, pregnant or lactating women, metabolic comorbidities, coexistence of other immune-mediated inflammatory diseases.

MUC1 downregulation promotes TNF-α-induced necroptosis in human bronchial epithelial cells via regulation of the RIPK1/RIPK3 pathway

MUC1 (mucin 1), a membrane-tethered mucin glycoprotein, is highly expressed on the surface of respiratory epithelial cells and plays a key role in anti-inflammatory and antiapoptotic responses against infections. However, little is known about the link between MUC1 and necroptosis in asthma. This study aimed to investigate the effects of MUC1 on TNF-α-induced necroptosis in human bronchial epithelial (16HBE) cells and the underlying molecular mechanism. Negative control and MUC1-siRNA cells were treated with TNF-α in the presence or absence of necrostatin-1 (Nec-1). Necroptosis was investigated using flow cytometry analyses, and the protein expression levels of MUC1, receptor-interacting protein kinase-1 (RIPK1), RIPK3, and phosphorylated RIPK1 were detected by western blot analysis. In addition, the interactions between RIPK and MUC1 were analyzed by coimmunoprecipitation. The results demonstrated that TNF-α could induce necroptosis of 16HBE cells, and MUC1 expression was increased upon treatment with TNF-α. The coimmunoprecipitation outcomes showed that MUC1 interacted with RIPK1 but not with RIPK3 in 16HBE cells, and the interaction was augmented by TNF-α. Furthermore, MUC1 downregulation obviously increased the TNF-α-induced necroptosis of 16HBE cells and enhanced the expression of p-RIPK1-Ser166 and RIPK3, whereas these phenomena were partially attenuated by Nec-1. These results may provide a new insight into the mechanism of severe asthma-related necroptosis and lay a foundation for the future development of new anti-inflammatory drugs for asthma.

Attenuation of hyperoxic acute lung injury by Lycium barbarum polysaccharide via inhibiting NLRP3 inflammasome

Lycium barbarum polysaccharide (LBP), an active component from Goji berry which is a traditional Chinese medicine, has anti-inflammatory and antioxidant features. The aim of our study was to investigate whether LBP has any role in hyperoxia-induced acute lung injury (ALI). Using a murine model of hyperoxia-induced ALI, we investigate the effect of LBP on pulmonary pathological changes as well as Sirtuin 1 (SIRT1) and the nucleotide binding domain and leucine-rich repeat pyrin domain containing 3 (NLRP3) inflammasome. Exposure to 100% oxygen for 72 h in male C57BL/6 mice resulted in increased protein levels of tumor necrosis factor-α and interleukin-1β in lung tissues, and aggravated lung histological alterations. These hyperoxia-induced changes and mortality were improved by LBP. LBP markedly suppressed the activation of NLRP3 inflammasome both in vivo and in vitro. Moreover, LBP upregulated SIRT1 expression compared with vehicle-treated group. Importantly, knockdown of SIRT1 reversed the inhibitory effect of LBP on NLRP3 inflammasome activation in vitro. LBP meliorated hyperoxia-induced ALI in mice by SIRT1-dependent inhibition of NLRP3 inflammasome activation.

New therapeutic strategies for IPF: Based on the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages

Pulmonary fibrosis is a chronic and progressive interstitial lung disease of known and unknown etiology. Over the past decades, macrophages have been recognized to play a significant role in IPF pathogenesis. According to their anatomical loci, macrophages can be divided to alveolar macrophages (AMs) subtypes and interstitial macrophages subtypes (IMs) with different responsibility in the damage defense response. Depending on diverse chemokines and cytokines in local microenvironments, macrophages can be induced and polarized to either classically activated (M1) or alternatively activated (M2) phenotypes in different stages of immunity. Therefore, we hypothesize that there is a "phagocytosis-secretion-immunization" network regulation of pulmonary macrophages related to a number of chemokines and cytokines. In this paper, we summarize and discuss the role of chemokines and cytokines involved in the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages, pointing toward novel therapeutic approaches based on the network target regulation in the field. Therapeutic strategies focused on modifying the chemokines, cytokines and the network are promising for the pharmacotherapy of IPF. Some Traditional Chinese medicines may have more superiorities in delaying the progression of pulmonary fibrosis for their multi-target activities of this network regulation.

Role of Macrophages in Acute Lung Injury and Chronic Fibrosis Induced by Pulmonary Toxicants

A diverse group of toxicants has been identified that cause injury to the lung including gases (eg, ozone, chlorine), particulates/aerosols (eg, diesel exhaust, fly ash, other combustion products, mustards, nanomaterials, silica, asbestos), chemotherapeutics (eg, bleomycin), and radiation. The pathologic response to these toxicants depends on the dose and duration of exposure and their physical/chemical properties. A common response to pulmonary toxicant exposure is an accumulation of proinflammatory/cytotoxic M1 macrophages at sites of tissue injury, followed by the appearance of anti-inflammatory/wound repair M2 macrophages. It is thought that the outcome of the pathogenic responses to toxicants depends on the balance in the activity of these macrophage subpopulations. Overactivation of either M1 or M2 macrophages leads to injury and disease pathogenesis. Thus, the very same macrophage-derived mediators, released in controlled amounts to destroy injurious materials and pathogens (eg, reactive oxygen species, reactive nitrogen species, proteases, tumor necrosis factor α) and initiate wound repair (eg, transforming growth factor β, connective tissue growth factor, vascular endothelial growth factor), can exacerbate acute lung injury and/or induce chronic disease such as fibrosis, chronic obstructive pulmonary disease, and asthma, when released in excess. This review focuses on the role of macrophage subsets in acute lung injury and chronic fibrosis. Understanding how these pathologies develop following exposure to toxicants, and the contribution of resident and inflammatory macrophages to disease pathogenesis may lead to the development of novel approaches for treating lung diseases.

Ovalbumin-sensitized mice have altered airway inflammation to agriculture organic dust

Agriculture exposures are associated with reducing the risk of allergy and asthma in early life; yet, repeated exposures later in life are associated with chronic bronchitis and obstructive pulmonary diseases. The objective of this study was to investigate the airway inflammatory response to organic dust extract (ODE) in mice with established ovalbumin (OVA)-induced experimental asthma. C57BL/6 mice were either OVA sensitized/aerosol-exposed or saline (Sal) sensitized/aerosol-challenged. Both groups were then subsequently challenged once with intranasal saline or swine confinement ODE to obtain 4 treatment groups of Sal-Sal, Sal-ODE, OVA-Sal, and OVA-ODE. Airway hyper-responsiveness (AHR) to methacholine, bronchiolar lavage fluid, lung tissues, and serum were collected. Intranasal inhalation of ODE in OVA-treated (asthmatic) mice (OVA-ODE) increased AHR and total cellular influx marked by elevated neutrophil and eosinophil counts. Flow cytometry analysis further demonstrated that populations of CD11chi dendritic cells (DC), CD3+ T cells, CD19+ B cells, and NKp46+ group 3 innate lymphoid cells (ILC3) were increased in lavage fluid of OVA-ODE mice as compared to ODE or OVA alone. Alveolar macrophages, DC, and T cells were significantly increased with co-exposure to OVA-ODE as compared to OVA alone. Lung ILC2 and ILC3 were only increased in OVA-Sal mice. Cytokine/chemokine levels varied with exposure to OVA-ODE reflecting an additive mixture of the pro- and allergic-inflammatory profiles. Collectively, ODE increased airway inflammatory cells and chemotactic mediator release in allergic (OVA) sensitized mice to suggest that persons with allergy/asthma be identified and warned prior to the occupational exposure of potentially worsening airway disease.

Biomarkers for Acute Respiratory Distress syndrome and prospects for personalised medicine

Acute lung injury (ALI) affects over 10% of patients hospitalised in critical care, with acute respiratory distress syndrome (ARDS) being the most severe form of ALI and having a mortality rate in the region of 40%. There has been slow but incremental progress in identification of biomarkers that contribute to the pathophysiology of ARDS, have utility in diagnosis and monitoring, and that are potential therapeutic targets (Calfee CS, Delucchi K, Parsons PE, Thompson BT, Ware LB, Matthay MA, Thompson T, Ware LB, Matthay MA, Lancet Respir Med 2014, 2:611–-620). However, a major issue is that ARDS is such a heterogeneous, multi-factorial, end-stage condition that the strategies for “lumping and splitting” are critical (Prescott HC, Calfee CS, Thompson BT, Angus DC, Liu VX, Am J Respir Crit Care Med 2016, 194:147–-155). Nevertheless, sequencing of the human genome, the availability of improved methods for analysis of transcription to mRNA (gene expression), and development of sensitive immunoassays has allowed the application of network biology to ARDS, with these biomarkers offering potential for personalised or precision medicine (Sweeney TE, Khatri P, Toward precision medicine Crit Care Med; 2017 45:934-939).

Biomarker panels have potential applications in molecular phenotyping for identifying patients at risk of developing ARDS, diagnosis of ARDS, risk stratification and monitoring. Two subphenotypes of ARDS have been identified on the basis of blood biomarkers: hypo-inflammatory and hyper-inflammatory. The hyper-inflammatory subphenotype is associated with shock, metabolic acidosis and worst clinical outcomes. Biomarkers of particular interest have included interleukins (IL-6 and IL-8), interferon gamma (IFN-γ), surfactant proteins (SPD and SPB), von Willebrand factor antigen, angiopoietin 1/2 and plasminogen activator inhibitor-1 (PAI-1). In terms of gene expression (mRNA) in blood there have been found to be increases in neutrophil-related genes in sepsis-induced and influenza-induced ARDS, but whole blood expression does not give a robust diagnostic test for ARDS.

Despite improvements in management of ARDS on the critical care unit, this complex disease continues to be a major life-threatening event. Clinical trials of β₂-agonists, statins, surfactants and keratinocyte growth factor (KGF) have been disappointing. In addition, monoclonal antibodies (anti-TNF) and TNFR fusion protein have also been unconvincing. However, there have been major advances in methods of mechanical ventilation, a neuromuscular blocker (cisatracurium besilate) has shown some benefit, and stem cell therapy is being developed. In the future, by understanding the role of biomarkers in the pathophysiology of ARDS and lung injury, it is hoped that this will provide rational therapeutic targets and ultimately improve clinical care (Seymour CW, Gomez H, Chang CH, Clermont G, Kellum JA, Kennedy J, Yende S, Angus DC, Crit Care 2017, 21:257).

Macrophage-targeted drugamers with enzyme-cleavable linkers deliver high intracellular drug dosing and sustained drug pharmacokinetics against alveolar pulmonary infections

Intracellular bacterial infections localized to the lung alveolar macrophage (AM) remain one of the most challenging settings for antimicrobial therapy. Current systemic antibiotic treatment fails to deliver sustained doses to intracellular bacterial reservoirs, which necessitates prolonged treatment regimens. Herein, we demonstrate a new intracellular enzyme-cleavable polymeric prodrug with tailored ciprofloxacin release profiles in the lungs and AM. The targeted polymeric prodrug, termed "drugamers", incorporates (1) hydrophilic mannose residues to solubilize the antibiotic cargo and to target and enhance AM uptake and intracellular delivery, and (2) enzyme-cleavable linkage chemistry to provide high and sustained intracellular AM drug dosing. Prodrug monomers, derived from the antibiotic ciprofloxacin, were synthesized with either an intracellular protease cleavable dipeptide linker or a hydrolytic phenyl ester linker. RAFT polymerization was used to copolymerize the prodrug monomers and mannose monomer to synthesize well-defined drugamers without requiring a post-polymerization conjugation step. In addition to favorable in vivo safety profiles following intratracheal administration, a single dose of the drugamers sustained ciprofloxacin dosing in lungs and AMs above the minimum inhibitory concentration (MIC) over at least a 48 h period. The enzyme-cleavable therapeutic achieved a >10-fold increase in sustained ciprofloxacin in AM, and maintained a significantly higher whole lung PK as well. Ciprofloxacin dosed in identical fashion displayed rapid clearance with a half-life of approximately 30 min. Notably, inhalation of the mannose-targeted ciprofloxacin drugamers achieved full survival (100%) in a highly lethal mouse model of pneumonic tularemia, contrasted with 0% survival using free ciprofloxacin. These findings demonstrate the versatility of the drugamer platform for engineering the intracellular pharmacokinetic profiles and its strong therapeutic activity in treating pulmonary intracellular infections.

YiQiFuMai lyophilized injection attenuates particulate matter-induced acute lung injury in mice via TLR4-mTOR-autophagy pathway

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are the serious diseases that are characterized by a severe inflammatory response of lung injuries and damage to the microvascular permeability, frequently resulting in death. YiQiFuMai (YQFM) lyophilized injection powder is a redeveloped preparation based on the well-known traditional Chinese medicine formula Sheng-Mai-San which is widely used in clinical practice in China, mainly for the treatment of microcirculatory disturbance-related diseases. However, there is little information about its role in ALI/ARDS. The aim of this study was to determine the protective effect of YQFM on particulate matter (PM)-induced ALI. The mice were intratracheally instilled with 50 mg/kg body weight of Standard Reference Material1648a (SRM1648a) in the PM-induced group. The mice in the YQFM group were given YQFM (three doses: 0.33, 0.67, and 1.34 g/kg) by tail vein injection 30 min after the intratracheal instillation of PM. The results showed that YQFM markedly reduced lung pathological injury and the lung wet/dry weight ratios induced by PM. Furthermore, we also found that YQFM significantly inhibited the PM-induced myeloperoxidase (MPO) activity in lung tissues, decreased the PM-induced inflammatory cytokines including interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), reduced nitric oxide (NO) and total protein in bronchoalveolar lavage fluids (BALF), and effectively attenuated PM-induced increases lymphocytes in BALF. In addition, YQFM increased mammalian target of rapamycin (mTOR) phosphorylation and dramatically suppressed the PM-stimulated expression of toll-like receptor 4 (TLR4), MyD88, autophagy-related protein LC3Ⅱand Beclin 1 as well as autophagy. In conclusion, these findings indicate that YQFM had a critical anti-inflammatory effect due to its ability to regulate both TLR4-MyD88 and mTOR-autophagy pathways, and might be a possible therapeutic agent for PM-induced ALI.

Sub-chronic inhalation of reclaimed water-induced fibrotic lesion in a mouse model

When reclaimed water is used as municipal miscellaneous water, acute exposure of the generated aerosol with high levels of endotoxins can cause severe inflammation in the lungs. However, the potential risks of long-term inhalation of reclaimed water remains unclear. To identify the adverse effects of sub-chronic reclaimed water inhalation and explain the underlying mechanisms, a mouse model of 12-week sub-chronic exposure was established, and wastewater before a membrane bioreactor (MBR, positive control) and the MBR effluent (reclaimed water, which met the quality standard of urban use and was currently used for landscape irrigation) were tested in this study. The exposure dose was set to approach the real working scenarios. Lung lavage and histology were analyzed. Obvious epithelial cell apoptosis in the bronchi was observed, along with the accumulation of myofibroblasts and the collagen deposition both in main bronchi and terminal bronchioles. All these symptoms were persistent after 4 weeks of recovery. Inflammation and induced bronchus-associated lymphoid tissues (iBALT) were also observed but diminished after recovery indicating inflammation may not be the direct cause of the symptom. Furthermore, two fibrogenic cytokines (TNF-α and TGF-β) were constantly high in the lung during the study. They might be the biomarkers of lung damage after the inhalation of reclaimed water. Adaptive immune responses were also detected as elevated levels of IgG and IgA, but not for IgE. Inhalation of reclaimed water causes sustained fibrotic lesions in the lungs, which suggests potential health risks during urban application where aerosols generated.

The Influence of BuqiHuoxueTongluo Formula on Histopathology and Pulmonary Function Test in Bleomycin-Induced Idiopathic Pulmonary Fibrosis in Rats

BuqiHuoxueTongluo Formula (BHTF) is an effective herbal prescription based on traditional Chinese medicine for idiopathic pulmonary fibrosis (IPF). The aim of this study was to elucidate the influence of BHTF on induced IPF model through the aspect of histopathology and pulmonary function test. Wistar rats with bleomycin-induced IPF were given BHTF via intragastric gavage. After 14 days and 28 days of treatment, respectively, on these two time points, we first performed pulmonary function test, performed ventilation measure, and traced the Pressure-Volume Loop under anesthesia. Then, rats were sacrificed for hematoxylin-eosin and Masson's trichrome staining, immunohistochemistry staining of TGF-β1 and α-SMA, and observation through transmission electron microscope. BHTF reduced infiltration of inflammation cells, collagen deposition, and fibrosis proliferation in pulmonary mesenchyme, inhibited the expression of TGF-β1 and α-SMA, and avoided the abnormality of ultrastructure and quantities of lamellar bodies. It also ameliorated the parameters of FVC, MVV, PEF, FEF25, and Cdyn, maintained the shape of the Pressure-Volume Loop, and improved hysteresis. BHFT relieved the histopathologic changes, improved ventilation function, compliance, and work of breathing, meliorated the capacity and elasticity of the lungs, and stabilized the alveolar surface tension. Further speaking, it had a potential impact on the secretion of pulmonary surfactant.