Oral lovastatin attenuates airway inflammation and mucus secretion in ovalbumin-induced murine model of asthma

Atorvastatin attenuates intestinal mucositis induced by 5-fluorouracil in mice by modulating the epithelial barrier and inflammatory response

Chemotherapy-induced intestinal mucositis is a major side effect of cancer treatment. Statins are 3-hydroxy-3-methyl glutaryl coenzyme reductase inhibitors used to treat hypercholesterolemia and atherosclerotic diseases. Recent studies have demonstrated that atorvastatin (ATV) has antioxidant, anti-inflammatory, and resulting from the regulation of different molecular pathways. In the present study, we investigated the effects of ATV on intestinal homeostasis in 5-fluorouracil (5-FU)-induced mucositis. Our results showed that ATV protected the intestinal mucosa from epithelial damage caused by 5-FU mainly due to inflammatory infiltrate and intestinal permeability reduction, downregulation of inflammatory markers, such as Tlr4, MyD88, NF-κB, Tnf-a, Il1β, and Il6 dose-dependent. ATV also improved epithelial barrier function by upregulating the mRNA transcript levels of mucin 2 (MUC2), and ZO-1 and occludin tight junction proteins. The results suggest that the ATV anti-inflammatory and protective effects on 5-FU-induced mice mucositis involve the inhibition of the TLR4/MYD88/NPRL3/NF-κB, iNos, and caspase 3.

Real-World Effectiveness of Statin Therapy in Adult Asthma

BACKGROUND

Blood lipids affect airway inflammation in asthma. Although several studies have suggested anti-inflammatory effects of statins on asthmatic airways, further studies are needed to clarify the long-term effectiveness of statins on asthma control and whether they are an effective treatment option.

OBJECTIVE

To evaluate the long-term effectiveness of statins in the chronic management of adult asthma in real-world practice.

METHODS

Electronic medical record data spanning 28 years, collected from the Ajou University Medical Center in Korea, were used to conduct a retrospective study. Clinical outcomes were compared between patients with asthma who had maintained statin use (the statin group) and those not taking statins, whose blood lipid tests were always normal (the non-statin group). We performed propensity score matching and calculated hazard ratios with 95% CIs using the Cox proportional hazards model. Severe asthma exacerbation was the primary outcome; asthma exacerbation, asthma-related hospitalization, and new-onset type 2 diabetes mellitus and hypertension were secondary outcomes.

RESULTS

After 1:1 propensity score matching, the statin and non-statin groups each included 545 adult patients with asthma. The risk of severe asthma exacerbations and asthma exacerbations was significantly lower in the statin group than in the non-statin group (hazard ratios [95% CI] = 0.57 [0.35-0.90] and 0.71 [0.52-0.96], respectively). There were no significant differences in the risk of asthma-related hospitalization or new-onset type 2 diabetes mellitus or hypertension between groups (0.76 [0.53-1.09], 2.33 [0.94-6.59], and 1.71 [0.95-3.17], respectively).

CONCLUSION

Statin use is associated with a lower risk of asthma exacerbation, with better clinical outcomes in adult asthma.

Cholesterol biosynthetic pathway induces cellular senescence through ERRα

Cellular senescence is a cell program induced by various stresses that leads to a stable proliferation arrest and to a senescence-associated secretory phenotype. Accumulation of senescent cells during age-related diseases participates in these pathologies and regulates healthy lifespan. Recent evidences point out a global dysregulated intracellular metabolism associated to senescence phenotype. Nonetheless, the functional contribution of metabolic homeostasis in regulating senescence is barely understood. In this work, we describe how the mevalonate pathway, an anabolic pathway leading to the endogenous biosynthesis of poly-isoprenoids, such as cholesterol, acts as a positive regulator of cellular senescence in normal human cells. Mechanistically, this mevalonate pathway-induced senescence is partly mediated by the downstream cholesterol biosynthetic pathway. This pathway promotes the transcriptional activity of ERRα that could lead to dysfunctional mitochondria, ROS production, DNA damage and a p53-dependent senescence. Supporting the relevance of these observations, increase of senescence in liver due to a high-fat diet regimen is abrogated in ERRα knockout mouse. Overall, this work unravels the role of cholesterol biosynthesis or level in the induction of an ERRα-dependent mitochondrial program leading to cellular senescence and related pathological alterations.

Bioinformatic Analysis of Key Regulatory Genes in Adult Asthma and Prediction of Potential Drug Candidates

Asthma is a common chronic disease that is characterized by respiratory symptoms including cough, wheeze, shortness of breath, and chest tightness. The underlying mechanisms of this disease are not fully elucidated, so more research is needed to identify better therapeutic compounds and biomarkers to improve disease outcomes. In this present study, we used bioinformatics to analyze the gene expression of adult asthma in publicly available microarray datasets to identify putative therapeutic molecules for this disease. We first compared gene expression in healthy volunteers and adult asthma patients to obtain differentially expressed genes (DEGs) for further analysis. A final gene expression signature of 49 genes, including 34 upregulated and 15 downregulated genes, was obtained. Protein-protein interaction and hub analyses showed that 10 genes, including POSTN, CPA3, CCL26, SERPINB2, CLCA1, TPSAB1, TPSB2, MUC5B, BPIFA1, and CST1, may be hub genes. Then, the L1000CDS² search engine was used for drug repurposing studies. The top approved drug candidate predicted to reverse the asthma gene signature was lovastatin. Clustergram results showed that lovastatin may perturb MUC5B expression. Moreover, molecular docking, molecular dynamics simulation, and computational alanine scanning results supported the notion that lovastatin may interact with MUC5B via key residues such as Thr80, Thr91, Leu93, and Gln105. In summary, by analyzing gene expression signatures, hub genes, and therapeutic perturbation, we show that lovastatin is an approved drug candidate that may have potential for treating adult asthma.

Identification of Druggable Genes for Asthma by Integrated Genomic Network Analysis

Asthma is a common and heterogeneous disease characterized by chronic airway inflammation. Currently, the two main types of asthma medicines are inhaled corticosteroids and long-acting β2-adrenoceptor agonists (LABAs). In addition, biological drugs provide another therapeutic option, especially for patients with severe asthma. However, these drugs were less effective in preventing severe asthma exacerbation, and other drug options are still limited. Herein, we extracted asthma-associated single nucleotide polymorphisms (SNPs) from the genome-wide association studies (GWAS) and phenome-wide association studies (PheWAS) catalog and prioritized candidate genes through five functional annotations. Genes enriched in more than two categories were defined as “biological asthma risk genes.” Then, DrugBank was used to match target genes with FDA-approved medications and identify candidate drugs for asthma. We discovered 139 biological asthma risk genes and identified 64 drugs targeting 22 of these genes. Seven of them were approved for asthma, including reslizumab, mepolizumab, theophylline, dyphylline, aminophylline, oxtriphylline, and enprofylline. We also found 17 drugs with clinical or preclinical evidence in treating asthma. In addition, eleven of the 40 candidate drugs were further identified as promising asthma therapy. Noteworthy, IL6R is considered a target for asthma drug repurposing based on its high target scores. Through in silico drug repurposing approach, we identified sarilumab and satralizumab as the most promising drug for asthma treatment.

Therapeutic effect of statins on airway remodeling during asthma

INTRODUCTION

Asthma is a chronic inflammatory disease of the airways, which is usually characterized by remodeling, hyperresponsiveness and episodic obstruction of the airways. The underlying chronic airway inflammation leads to pathological restructuring of both the large and small airways. Since the effects of current asthma medications on airway remodeling have been met with contradictions, many therapeutic agents have been redirected from their primary use for the treatment of asthma. Such treatments, which could target several signaling molecules implicated in the inflammatory and airway remodeling processes of asthma, would be an ideal choice.

AREAS COVERED

Statins are effective serum cholesterol-lowering agents that were found to have potential anti-inflammatory and anti-remodeling properties. Literature search was done for the past 10 years to include research and review articles in the field of statins and asthma complications. In this review, we discuss the role of statins in airway tissue remodeling and their potential therapeutic modalities in asthma.

EXPERT OPINION

With improved understanding of the role of statins in airway remodeling and inflammation, statins represent a potential therapeutic option for various asthma phenotypes. Further research is warranted to optimize statins for asthma therapy through inhalation as a possible route of administration.

Panax notoginseng saponin R1 modulates TNF-α/NF-κB signaling and attenuates allergic airway inflammation in asthma

BACKGROUD

Panax notoginseng saponin R1 (PNS-R1) is one of the most important chemical monomers derived from the panax notoginseng, and our previous study found that PNS-R1 reduced glucocorticoid-induced apoptosis in asthmatic airway epithelial cells. Thus, in this study, we explored the effects of the PNS-R1 on inflammation of allergic asthma.

METHODS

The asthmatic mice were administered 15 mg/kg PNS-R1 by intraperitoneal injection three days before sensitized to OVA. The effects of PNS-R1 on asthmatic mice were detected by airway hyperresponsiveness, inflammation, mucus hypersecretion and inflammatory cytokines such as interleukin (IL)-13, IL-4, IL-5, IL-8 and tumor necrosis factor (TNF)-α were studied. We also treated human bronchial epithelial cells (16HBE) with house dust mites (HDM) and then detected the secretion of cellular inflammatory factors (IL-13 and TNF-α). Western blot and immunofluorescence were used to examine the effect of PNS-R1 on TNF-α/NF-κB pathway. TNF-α/NF-κB/IKK signal pathway activator was used in PNS-R1-treated asthmatic mice.

RESULTS

PNS-R1 significantly reduced the airway inflammatory, mucus secretion and hyperresponsiveness in asthma model. It also reduced the levels of IL-13, IL-4, IL-5 and IL-8 in bronchoalveolar lavage fluid (BALF) and IgE and OVA-specific IgE in serum for asthma mice. PNS-R1 reduced IL-13 and TNF-α secretion in HDM-treated 16HBE cells. In addition, PNS-R1 suppressed TNF-α/NF-κB pathway in both asthmatic mice and 16HBE. Activation of NF-kB pathway reversed the therapeutic effect of PNS-R1 on asthmatic mice.

CONCLUSION

The results indicated that PNS-R1 effectively suppresses allergic airway inflammation of asthma partly through TNF-α/NF-κB pathway. PNS-R1 may play a potential role in allergic asthma treatment in the future.

Fungal allergen-induced IL-33 secretion involves cholesterol-dependent, VDAC-1-mediated ATP release from the airway epithelium

KEY POINTS

Alternaria aeroallergens induce the release of ATP from human bronchial epithelial (HBE) cells by activating a conductive pathway involving voltage-dependent anion channel-1 (VDAC-1) and by exocytosis of ATP localized within membrane vesicles. Inhibition of VDAC-1 blocked Alternaria-evoked Ca²⁺ uptake across the plasma membrane of HBE cells and interleukin (IL)-33 release into the extracellular media. Reducing cholesterol content with a cholesterol scavenger (β-methylcyclodextrin) or statin compound (simvastatin) blocked ATP and IL-33 release by lowering the expression of VDAC-1 in the plasma membrane. Pretreatment with simvastatin for 24 h also inhibited the increase in tight junction macromolecule permeability that occurs following Alternaria exposure. These results establish a novel role for VDAC-1 as a mechanism underlying ATP release induced by fungal allergens and suggests a possible therapeutic use for cholesterol lowering compounds in reducing Alternaria-stimulated allergic inflammation.

ABSTRACT

Human bronchial epithelial (HBE) cells exposed to allergens derived from the common saprophytic fungus, Alternaria alternata release ATP, which in turn stimulates P2X₇ receptor-mediated Ca²⁺ uptake across the plasma membrane. The subsequent increase in intracellular calcium concentration induces proteolytic processing and secretion of interleukin (IL)-33, a critical cytokine involved in the initiation of allergic airway inflammation. A major objective of the present study was to identify the mechanism responsible for conductive ATP release. The results show that pretreatment of HBE cells with inhibitors of the voltage-dependent anion channel-1 (VDAC-1) or treatment with a VDAC-1 selective blocking antibody or silencing mRNA expression of the channel by RNA interference, inhibit Alternaria-evoked ATP release. Moreover, inhibition of VDAC-1 channel activity or reducing protein expression blocked the secretion of IL-33. Similarly, reducing the cholesterol content of HBE cells with simvastatin or the cholesterol scavenger β-methylcyclodextrin also blocked ATP release and IL-33 secretion by decreasing the level of VDAC-1 expression in the plasma membrane. In addition, simvastatin inhibited the increase in tight junction macromolecule permeability that was previously observed after Alternaria exposure. These results demonstrate a novel function for VDAC-1 as the conductive mechanism responsible for Alternaria-induced ATP release, an essential early step in the processing, mobilization and secretion of IL-33 by the airway epithelium. Furthermore, the simvastatin-evoked reduction of VDAC-1 expression in the plasma membrane, suggests the possibility that cholesterol lowering compounds may be beneficial in alleviating allergic airway inflammation induced by fungal allergens.

Scrophularia buergeriana attenuates allergic inflammation by reducing NF-κB activation

BACKGROUND

Scrophularia buergeriana Miq. (Scrophulariaceae) (SB) has been used as an oriental medicine for the treatment of inflammatory diseases, such as neuritis and pharyngolaryngitis.

PURPOSE

We explored the therapeutic effects of S. buergeriana ethanol extract (SBE) on airway inflammation in ovalbumin (OVA)-induced asthmatic mice and lipopolysaccharide (LPS)-stimulated RAW264.7 cells.

METHODS

Mice were intraperitoneally injected with OVA on days 0 and 14 to elevate the immune response. On days 21 to 23, the mice were challenged with OVA solution and SBE (20 and 40 mg/kg) was administered daily by oral gavage from days 18 to 23. RAW264.7 cells were pretreated with SBE 1 h before LPS stimulation.

RESULTS

SBE administration effectively suppressed inflammatory cell infiltration, the expression of interleukin (IL)-5, IL-13, and IL-17, immunoglobulin E, and airway hyperresponsiveness in an OVA-induced allergic asthma model. A reduction in histological alterations, including airway inflammation and mucus hypersecretion, was observed. These effects of SBE were accompanied by a decrease in matrix metalloproteinase-9 (MMP-9) expression and nuclear factor kappa B (NF-κB) phosphorylation. These responses were observed in LPS-stimulated RAW264.7 cells. SBE treatment reduced the mRNA expression of tumor necrosis factor (TNF)-α, IL-6, and MMP-9, and NF-κB phosphorylation, in LPS-stimulated RAW264.7 cells.

CONCLUSION

Our results indicated that SBE effectively attenuated airway inflammation in an OVA-induced allergic asthma model. These properties of SBE were thought to be involved in the suppression of NF-κB phosphorylation, suggesting that the material has the potential to regulate the development of allergic asthma.

Rosuvastatin suppresses cytokine production and lung inflammation in asthmatic, hyperlipidemic and asthmatic-hyperlipidemic rat models

BACKGROUND

Given the role that T lymphocytes play on the pathogenesis of allergic asthma, drugs targeting Th2 and Th17 cells may be a hopeful therapeutic strategy. This study aimed to evaluate the effect of rosuvastatin treatment on cytokine production and lung inflammation in allergic asthma.

METHODS

The animals were assigned into control (C), asthmatic (A), hyperlipidemic (H), asthmatic-hyperlipidemic (AH), rosuvastatin (40 mg/kg/day intraperitoneally, for 3 weeks)-treated asthmatic (AR), rosuvastatin-treated hyperlipidemic (HR) and rosuvastatin-treated asthmatic-hyperlipidemic (AHR) groups (n = 6 in each group). The levels of IL-4, IFN-γ and IL-17, total and differential WBC counts in bronchoalveolar lavage fluid (BALF), Th1/Th2 balance, and pathological changes were evaluated.

RESULTS

The BALF level of IL-4 in A, H and AH groups, and IL-17A in A and AH groups were significantly higher than that in C group (p < 0.05 to p < 0.001). IFN-γ level and Th1/Th2 balance (IFN‑γ/IL-4 ratio) in A and AH groups were significantly decreased (p < 0.05 to p < 0.01). Inflammatory cells infiltration, muscle hypertrophy and emphysema were also observed in A and AH groups. The BALF levels of IL-4 in AR, HR and AHR groups, IFN-γ level in HR group, and IL-17A level in AR and AHR groups showed a significant improvement compared to that of A, H and AH groups (p < 0.05 to p < 0.001). Rosuvastatin treatment increased Th1/Th2 balance in all treated groups (p < 0.05 to p < 0.01), decreased total WBC counts, neutrophilia, eosinophilia and lung inflammation in AR and AHR groups, and improved muscle hypertrophy and emphysema in AHR group.

CONCLUSIONS

Rosuvastatin treatment improved lung pathological changes by suppression of Th2 and Th17-mediated cytokines which was unrelated to its lipid-lowering activity. Therefore, rosuvastatin might be a candidate immunomodulatory drug for treatment of patients with allergic asthma.

Identification of multiple dysregulated metabolic pathways by GC-MS-based profiling of liver tissue in mice with OVA-induced asthma exposed to PM2.5

Particulate matter (PM) exposure increases the risk of asthma. However, the effect of PM_2.5 exposure on liver metabolism in mice with asthma symptoms remains unclear. We established an ovalbumin (OVA)-induced asthma model in mice and divided the animals into four groups: control group (C), PM_2.5 exposure group (P), OVA-induced asthma group (O) and OVA-induced asthma PM_2.5 exposure group (OP). Gas chromatography-mass spectrometry (GC-MS) was used to identify the metabolite markers and related perturbed metabolic pathways in mouse liver tissue after PM_2.5 exposure. Multivariate analysis showed 9 and 12 potential metabolite markers in the P and OP groups, respectively, after PM_2.5 exposure that were significantly correlated with lipid peroxidation indices. PM_2.5 exposure perturbed 5 and 7 metabolic pathways in the P and OP groups, respectively. These metabolic pathways mainly involve the lipid metabolism, amino acid metabolism, carbohydrate metabolism, and nucleotide metabolism. These results highlight the potential to study PM_2.5-triggered alterations via liver tissue in normal and OVA-induced asthmatic mice to gain a more realistic appraisal of the resulting early toxicity events. Additionally, these results revealed potential metabolite markers of early antioxidant defense events triggered by PM_2.5 and indicated that metabolite markers are more sensitive than antioxidant indicators.

Repurposing of statins via inhalation to treat lung inflammatory conditions

Despite many therapeutic advancements over the past decade, the continued rise in chronic inflammatory lung diseases incidence has driven the need to identify and develop new therapeutic strategies, with superior efficacy to treat these diseases. Statins are one class of drug that could potentially be repurposed as an alternative treatment for chronic lung diseases. They are currently used to treat hypercholesterolemia by inhibiting the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, that catalyses the rate limiting step in the mevalonate biosynthesis pathway, a key intermediate in cholesterol metabolism. Recent research has identified statins to have other protective pleiotropic properties including anti-inflammatory, anti-oxidant, muco-inhibitory effects that may be beneficial for the treatment of chronic inflammatory lung diseases. However, clinical studies have yielded conflicting results. This review will summarise some of the current evidences for statins pleiotropic effects that could be applied for the treatment of chronic inflammatory lung diseases, their mechanisms of actions, and the potential to repurpose statins as an inhaled therapy, including a detailed discussion on their different physical-chemical properties and how these characteristics could ultimately affect treatment efficacies. The repurposing of statins from conventional anti-cholesterol oral therapy to inhaled anti-inflammatory formulation is promising, as it provides direct delivery to the airways, reduced risk of side effects, increased bioavailability and tailored physical-chemical properties for enhanced efficacy.

Fisetin-treatment alleviates airway inflammation through inhbition of MyD88/NF-κB signaling pathway

Asthma is a common chronic airway inflammation disease and is considered as a major public health problem. Fisetin (3,3′,4′,7-tetrahydroxyflavone) is a naturally occurring flavonoid abundantly found in different vegetables and fruits. Fisetin has been reported to exhibit various positive biological effects, including anti-proliferative, anticancer, anti-oxidative and neuroprotective effects. We evaluated the effects of fisetin on allergic asthma regulation in mice. Mice were first sensi-tized, then airway-challenged with ovalbumin (OVA). Whether fisetin treatment attenuated OVA-induced airway inflammation was examined via inflammation inhibition through MyD88-related NF-κB (p65) signaling pathway. Mice were divided into the control (Con), OVA-induced asthma (Mod), 40 (FL) and 50 (FH) mg/kg fisetin-treated OVA-induced asthma groups. Our results found that OVA-induced airway inflammation in mice caused a significant inflammatory response via the activation of MyD88 and NF-κB signaling pathways, leading to release of pro-inflammatory cytokines. In contrast, fisetin-treated mice after OVA induction inhibited activation of MyD88 and NF-κB signaling pathways, resulting in downregulation of pro-inflammatory cytokine secretion. Further, fisetin significantly ameliorated the airway hyperresponsiveness (AHR) towards methacholine (Mch). In addition, fisetin reduced the number of eosinophil, monocyte, neutrophil and total white blood cell in the bronchoalveolar lavage fluid (BALF) of OVA-induced mice. The serum and BALF samples obtained from the OVA-induced mice with fisetin showed lower levels of pro-inflammatory cytokines. The results of our study illustrated that fisetin may be a new promising candidate to inhibit airway inflammation response induced by OVA.

Statins in the treatment of COPD and asthma-where do we stand?

Asthma and chronic obstructive pulmonary disease (COPD) are the two most prevalent obstructive lung diseases that account for tremendous morbidity and mortality throughout the world. These diseases have strong inflammatory components, with multiple prior studies showing elevated levels of various inflammatory markers and cells in those with COPD and asthma. Therefore, efforts to target inflammation in management of these diseases are of great interest. Statins, which define a class of drugs that are HMG-CoA inhibitors, are used to decrease cholesterol levels and have also been described to have many pleotropic effects that include anti-inflammatory and anti-oxidative properties. These properties have led to multiple studies looking at the potential use of statins in decreasing inflammation in many diseases, including COPD and asthma. This review aims to address the current evidence behind the potential use of statins in the treatment of asthma and COPD.

Tomatidine Attenuates Airway Hyperresponsiveness and Inflammation by Suppressing Th2 Cytokines in a Mouse Model of Asthma

Tomatidine is isolated from the fruits of tomato plants and found to have anti-inflammatory effects in macrophages. In the present study, we investigated whether tomatidine suppresses airway hyperresponsiveness (AHR) and eosinophil infiltration in asthmatic mice. BALB/c mice were sensitized with ovalbumin and treated with tomatidine by intraperitoneal injection. Airway resistance was measured by intubation analysis as an indication of airway responsiveness, and histological studies were performed to evaluate eosinophil infiltration in lung tissue. Tomatidine reduced AHR and decreased eosinophil infiltration in the lungs of asthmatic mice. Tomatidine suppressed Th2 cytokine production in bronchoalveolar lavage fluid. Tomatidine also blocked the expression of inflammatory and Th2 cytokine genes in lung tissue. In vitro, tomatidine inhibited proinflammatory cytokines and CCL11 production in inflammatory BEAS-2B bronchial epithelial cells. These results indicate that tomatidine contributes to the amelioration of AHR and eosinophil infiltration by blocking the inflammatory response and Th2 cell activity in asthmatic mice.

Genipin inhibits allergic responses in ovalbumin-induced asthmatic mice

Genipin is a natural compound isolated from the fruit of Gardenia jasminoides with various pharmacological effects. In this study, we investigated whether genipin effectively alleviates allergic responses in a murine model of ovalbumin (OVA)-induced asthma. The mice were administered an intraperitoneal injection of OVA on day 0 and 14 to boost the immune response; genipin was then administered from day 18 to 23 by oral gavage. On days 21 to 23, mice were OVA-challenged using am ultrasonic nebulizer, and airway hyperresponsiveness (AHR) was determined on day 24 by plethysmography. Genipin significantly reduced the inflammatory cell count in bronchoalveolar lavage fluids (BALF) and AHR, which were accompanied by lower interleukin-5 (IL-5), IL-13 and OVA-specific immunoglobulin (Ig) E levels in the BALF or serum from OVA-induced asthmatic mice. In histology, genipin significantly decreased airway inflammation and mucus hypersecretion in OVA-induced asthmatic mice. Additionally, genipin inhibited OVA-induced increases in the expression of inducible nitric oxide synthase and cyclooxygenase-2 proteins. Further, genipin reduced the activity and protein levels of matrix metalloproteinase-9 in lung tissue from OVA induced asthmatic mice. Overall, genipin effectively alleviated the asthmatic inflammatory response in an OVA-induced asthmatic model. Therefore, our results suggest that genipin has therapeutic potential for treating asthma.

Therapeutic interventions for aging: the case of cellular senescence

Organismal aging is a multifactorial process characterized by the onset of degenerative conditions and cancer. One of the key drivers of aging is cellular senescence, a state of irreversible growth arrest induced by many pro-tumorigenic stresses. Senescent cells accumulate late in life and at sites of age-related pathologies, where they contribute to disease onset and progression through complex cell and non-cell autonomous effects. Here, we summarize the mechanisms by which cellular senescence can promote aging, and we offer an extensive description of current potential pharmacological interventions for senescent cells, highlighting limitations and suggesting alternatives.

Conjugated linoleic acids suppress inflammatory response and ICAM-1 expression through inhibition of NF-κB and MAPK signaling in human bronchial epithelial cells

Conjugated linoleic acids (CLAs) comprise a group of natural unsaturated fatty acids. CLA was reported to have anti-asthma, anti-adiposity, and anti-tumor effects. The present study aimed to evaluate the suppressive effects of cis-9, trans-11-CLA (c9,t11-CLA) on the expression of proinflammatory cytokines and intercellular adhesion molecule 1 (ICAM-1) in TNF-α-stimulated human bronchial epithelial (BEAS-2B) cells. After treating with various doses of c9,t11-CLA (12.5-100 μg ml(-1)), BEAS-2B cells were induced into an inflamed state by adding TNF-α or TNF-α/IL-4. The presence of c9,t11-CLA significantly suppressed the secretion of cytokines IL-6, IL-8, CCL5, and MCP-1. We also found that c9,t11-CLA inhibited ICAM-1 expression, and decreased monocyte adhesion to inflamed bronchial epithelial cells. Interestingly, c9,t11-CLA attenuated the phosphorylation of mitogen-activated protein kinase (MAPK) and down-regulated the activation of nuclear factor-κB (NF-κB). These results suggested that the anti-inflammatory effects of c9,t11-CLA were mediated by inhibiting proinflammatory cytokines, chemokines, and ICAM-1 expression by blocking NF-κB transcription regulation and by attenuating MAPK signaling pathways.

Administration of JTE013 abrogates experimental asthma by regulating proinflammatory cytokine production from bronchial epithelial cells

Background

Sphingosine-1-phosphate (S1P) is a bioactive phospholipid that acts as a signal transducer by binding to S1P receptors (S1PR) 1 to 5. The S1P/S1PRs pathway has been associated with remodeling and allergic inflammation in asthma, but the expression pattern of S1PR and its effects on non-immune cells have not been completely clarified. The aim of this study was to examine the contribution of the signaling of S1P and S1PRs expressed in airway epithelial cells (ECs) to asthma responses in mice.

Methods

Bronchial asthma was experimentally induced in BALB/c mice by ovalbumin (OVA) sensitization followed by an OVA inhalation challenge. The effects of S1PR antagonists on the development of asthma were analyzed 24 h after the OVA challenge.

Results

Immunohistological analysis revealed S1PR1-3 expression on mouse airway ECs. Quantitative real-time polymerase chain reaction demonstrated that S1P greatly stimulated the induction of CCL3 and TIMP2 mRNA in human airway ECs, i.e., BEAS-2B cells, in a dose-dependent manner. Pretreatment with the S1PR2 antagonist JTE013 inhibited the CCL3 gene expression in BEAS-2B cells. Immunohistological analysis also showed that the expression level of CCL3 was attenuated by JTE013 in asthmatic mice. Furthermore, JTE013 as well as anti-CCL3 antibody attenuated allergic responses. Intratracheal administration of JTE013 also attenuated eosinophilic reactions in bronchoalveolar lavage fluids. S1P induced transcription factor NFκB activation, while JTE013 greatly reduced the NFκB activation.

Conclusions

JTE013 attenuated allergic airway reactions by regulating CCL3 production from bronchial ECs. The intratracheal administration of JTE013 may be a promising therapeutic strategy for bronchial asthma.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-016-0465-x) contains supplementary material, which is available to authorized users.

Adalimumab ameliorates OVA-induced airway inflammation in mice: Role of CD4(+) CD25(+) FOXP3(+) regulatory T-cells

Asthma is a chronic inflammatory heterogeneous disorder initiated by a dysregulated immune response which drives disease development in susceptible individuals. Though T helper 2 (TH2) biased responses are usually linked to eosinophilic asthma, other Th cell subsets induce neutrophilic airway inflammation which provokes the most severe asthmatic phenotypes. A growing evidence highlights the role of T regulatory (Treg) cells in damping abnormal Th responses and thus inhibiting allergy and asthma. Therefore, strategies to induce or augment Treg cells hold promise for treatment and prevention of allergic airway inflammation. Recently, the link between Tumor necrosis factor-α (TNF-α) and Treg has been uncovered, and TNF-α antagonists are increasingly used in many autoimmune diseases. Yet, their benefits in allergic airway inflammation is not clarified. We investigated the effect of Adalimumab, a TNF-α antagonist, on Ovalbumin (OVA)-induced allergic airway inflammation in CD1 mice and explored its impact on Treg cells. Our results showed that Adalimumab treatment attenuated the OVA-induced increase in serum IgE, TH2 and TH1 derived inflammatory cytokines (IL-4 and IFN-γ, respectively) in bronchoalveolar lavage (BAL) fluid, suppressed recruitment of inflammatory cells in BAL fluid and lung, and inhibited BAL fluid neutrophilia. It also ameliorated goblet cell metaplasia and bronchial fibrosis. Splenocytes flow cytometry revealed increased percentage of CD4(+) CD25(+) FOXP3(+) Treg cells by Adalimumab that was associated with increase in their suppressive activity as shown by elevated BAL fluid IL-10. We conclude that the beneficial effects of Adalimumab in this CD1 neutrophilic model of allergic airway inflammation are attributed to augmentation of Treg cell number and activity.

MiR-3162-3p Is a Novel MicroRNA That Exacerbates Asthma by Regulating β-Catenin

Asthma is a common chronic respiratory disease. In a previous study, we found several circulating microRNA signatures associated with childhood asthma and selected miR-3162-3p for subsequent studies. Since the target proteins and underlying molecular mechanisms of miR-3162-3p in asthma etiopathogenesis are not well characterized, we designed this study to clarify its role. We employed bioinformatics and quantitative PCR methods as a first step to determine the target of miR-3162-3p, and we elucidated β-catenin. Luciferase assays and western blot analysis confirmed β-catenin as a direct target of miR-3162-3p as the 3'-untranslated region of β-catenin mRNA possesses a specific miR-3162-3p pairing site. The correlation between the expression levels of miR-3162-3p and β-catenin is confirmed by quantitative PCR and western blot studies in A549, Beas-2B and H1299 cell lines and OVA-induced asthma mouse model. Of note, upregulation of the endogenous miR-3162-3p level is concomitant with the reduction of β-catenin mRNA and protein expression levels. MiR-3162-3p antagomir treatment antagonizes the endogenous miR-3162-3p and effectively rescues the attenuation of endogenous β-catenin in OVA-induced asthmatic mice, which alleviates airway hyperresponsiveness and ameliorates airway inflammation. Collectively, our findings suggest a novel relationship between miR-3162-3p and β-catenin and clarify their mechanistic role in asthma etiopathogenesis.

Novel Therapies to Inhibit Mucus Synthesis and Secretion in Airway Hypersecretory Diseases

BACKGROUND

In asthma and chronic obstructive pulmonary disease (COPD), airway mucus hypersecretion contributes to impaired mucociliary clearance, mucostasis and, potentially, the development of mucus plugging of the airways.

SUMMARY

Excess mucus production can be targeted via therapies that focus on inhibition mucin synthesis, via reducing expression of mucin (MUC) genes, and/or inhibition of mucin secretion into the airways.

KEY MESSAGES

This review discusses a number of therapeutic approaches to reduce airway mucus in asthma and COPD, including the use of synthetic and natural products. In particular, it highlights areas where clinical trials of inhibitors of particular target molecules are lacking. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors are an example of a targeted therapy that has been researched to reduce mucus synthesis, as have inhibitors of EGFR's downstream signalling pathways, for example, mitogen-activated protein kinase-13 and hypoxia inducible factor-1. However, their efficacy and safety profiles are currently not up to the mark. There is clinical potential in Bio-11006, which reduces mucus secretion via the inhibition of myristoylated alanine-rich C-kinase substrate and is currently in Phase IIb trial.

Simvastatin suppresses breast cancer cell proliferation induced by senescent cells

Cellular senescence suppresses cancer by preventing the proliferation of damaged cells, but senescent cells can also promote cancer though the pro-inflammatory senescence-associated secretory phenotype (SASP). Simvastatin, an HMG-coA reductase inhibitor, is known to attenuate inflammation and prevent certain cancers. Here, we show that simvastatin decreases the SASP of senescent human fibroblasts by inhibiting protein prenylation, without affecting the senescent growth arrest. The Rho family GTPases Rac1 and Cdc42 were activated in senescent cells, and simvastatin reduced both activities. Further, geranylgeranyl transferase, Rac1 or Cdc42 depletion reduced IL-6 secretion by senescent cells. We also show that simvastatin mitigates the effects of senescent conditioned media on breast cancer cell proliferation and endocrine resistance. Our findings identify a novel activity of simvastatin and mechanism of SASP regulation. They also suggest that senescent cells, which accumulate after radio/chemo therapy, promote endocrine resistance in breast cancer and that simvastatin might suppress this resistance.

P2Y12 antagonist attenuates eosinophilic inflammation and airway hyperresponsiveness in a mouse model of asthma

Leukotriene E4 (LTE4) that plays a key role in airway inflammation is expressed on platelets and eosinophils. We investigated whether blocking of the P2Y12 receptor can suppress eosinophilic inflammation in a mouse model of asthma because platelets and eosinophils share this receptor to be activated. BALB/c mice were sensitized by intraperitoneal injection of ovalbumin (OVA), followed by OVA nebulization. On each challenge day, clopidogrel, a P2Y12 antagonist was administered 30 min. before each challenge. Forty‐eight hours after the last OVA challenge, mice were assessed for airway hyperresponsiveness (AHR), cell composition and cytokine levels, including chemokine ligand 5 (CCL5), in bronchoalveolar lavage (BAL) fluid. EOL cells were treated with LTE4, with or without clopidogrel treatment, and intracellular and extracellular eosinophil cationic protein (ECP) expressions were measured to find the inhibiting function of P2Y12 antagonist on eosinophilic activation. The levels of P2Y12 expression were increased markedly in the lung homogenates of OVA‐sensitized and ‐challenged mice after platelet depletion. Administration of clopidogrel decreased AHR and the number of airway inflammatory cells, including eosinophils, in BAL fluid following OVA challenge. These results were associated with decreased levels of Th2 cytokines and CCL5. Histological examination showed that inflammatory cells as well as mucus‐containing goblet cells were reduced in clopidogrel‐administered mice compared to vehicle‐treated mice. Clopidogrel inhibited extracellular ECP secretion after LTE4 stimulation in EOL‐1 cells. Clopidogrel could prevent development of AHR and airway inflammation in a mouse model of asthma. P2Y12 can be a novel therapeutic target to the suppression of eosinophils in asthma.

Statins in Asthma: Potential Beneficial Effects and Limitations

Asthma's sustenance as a global pandemic, across centuries, can be attributed to the lack of an understanding of its workings and the inability of the existing treatment modalities to provide a long lasting cure without major adverse effects. The discovery of statins boosted by a better comprehension of the pathophysiology of asthma in the past few decades has opened up a potentially alternative line of treatment that promises to be a big boon for the asthmatics globally. However, the initial excellent results from the preclinical and animal studies have not borne the results in clinical trials that the scientific world was hoping for. In light of this, this review analyzes the ways by which statins could benefit in asthma via their pleiotropic anti-inflammatory properties and explain some of the queries raised in the previous studies and provide recommendations for future studies in this field.

Administration of Pigment Epithelium-Derived Factor Inhibits Airway Inflammation and Remodeling in Chronic OVA-Induced Mice via VEGF Suppression

Purpose

Pigment epithelium-derived factor (PEDF) is a recently discovered antiangiogenesis protein. PEDF possesses powerful anti-inflammatory, antioxidative, antiangiogenic, and antifibrosis properties. It has been reported that PEDF can regulate vascular endothelial growth factor (VEGF) expression. This study aimed to evaluate whether recombinant PEDF protein could attenuate allergic airway inflammation and airway remodeling via the negative regulation of VEGF using a murine model of chronic ovalbumin (OVA)-induced asthma and BEAS-2B human bronchial epithelial cells.

Methods

In an in vivo experiment, mice sensitized with OVA were chronically airway challenged with aerosolized 1% OVA solution for 8 weeks. Treated mice were given injections of recombinant PEDF protein (50 or 100 µg/kg body weight) via the tail vein. In an in vitro experiment, we investigated the effects of recombinant PEDF protein on VEGF release levels in BEAS-2B cells stimulated with IL-1β.

Results

Recombinant PEDF protein significantly inhibited eosinophilic airway inflammation, airway hyperresponsiveness, and airway remodeling, including goblet cell hyperplasia, subepithelial collagen deposition, and airway smooth muscle hypertrophy. In addition, recombinant PEDF protein suppressed the enhanced expression of VEGF protein in lung tissue and bronchoalveolar lavage fluid (BALF) in OVA-challenged chronically allergic mice. In the in vitro experiment, VEGF expression was increased after IL-1β stimulation. Pretreatment with 50 and 100 ng/mL of recombinant PEDF protein significantly attenuated the increase in VEGF release levels in a concentration-dependent manner in BEAS-2B cells stimulated by IL-1β.

Conclusions

These results suggest that recombinant PEDF protein may abolish the development of characteristic features of chronic allergic asthma via VEGF suppression, providing a potential treatment option for chronic airway inflammation diseases such as asthma.

Glucagon Like Peptide-1 (GLP-1) Modulates OVA-Induced Airway Inflammation and Mucus Secretion Involving a Protein Kinase A (PKA)-Dependent Nuclear Factor-κB (NF-κB) Signaling Pathway in Mice

Asthma is a common chronic pulmonary inflammatory disease, featured with mucus hyper-secretion in the airway. Recent studies found that glucagon like peptide-1 (GLP-1) analogs, including liraglutide and exenatide, possessed a potent anti-inflammatory property through a protein kinase A (PKA)-dependent signaling pathway. Therefore, the aim of current study was to investigate the value of GLP-1 analog therapy liraglutide in airway inflammation and mucus secretion in a murine model of ovalbumin (OVA)-induced asthma, and its underlying molecular mechanism. In our study, BALB/c mice were sensitized and challenged by OVA to induce chronic asthma. Pathological alterations, the number of cells and the content of inflammatory mediators in bronchoalveolar lavage fluid (BALF), and mucus secretion were observed and measured. In addition, the mRNA and protein expression of E-selectin and MUC5AC were analyzed by qPCR and Western blotting. Then, the phosphorylation of PKA and nuclear factor-κB (NF-κB) p65 were also measured by Western blotting. Further, NF-κB p65 DNA binding activity was detected by ELISA. OVA-induced airway inflammation, airway mucus hyper-secretion, the up-regulation of E-selectin and MUC5AC were remarkably inhibited by GLP-1 in mice (all p < 0.01). Then, we also found that OVA-reduced phosphorylation of PKA, and OVA-enhanced NF-κB p65 activation and NF-κB p65 DNA binding activity were markedly improved by GLP-1 (all p < 0.01). Furthermore, our data also figured out that these effects of GLP-1 were largely abrogated by the PKA inhibitor H-89 (all p < 0.01). Taken together, our results suggest that OVA-induced asthma were potently ameliorated by GLP-1 possibly through a PKA-dependent inactivation of NF-κB in mice, indicating that GLP-1 analogs may be considered an effective and safe drug for the potential treatment of asthma in the future.

Cordycepin alleviates airway hyperreactivity in a murine model of asthma by attenuating the inflammatory process

Cordycepin (Cor), which is a naturally occurring nucleoside derivative isolated from Cordyceps militaris, has been shown to exert excellent antiinflammatory activity in a murine model of acute lung injury. Thus, this study aimed to evaluate the antiasthmatic activity of Cor (10, 20, and 40 mg/kg) and to investigate the possible underlying molecular mechanisms. We found that Cor attenuated airway hyperresponsiveness, mucus hypersecretion, and ovalbumin (Ova)-specific immunoglobulin (Ig) E, and alleviated lung inflammation with decreased eosinophils and macrophages in the bronchoalveolar lavage (BAL) fluid. Notably, Cor reduced the upregulation of eotaxin, intercellular cell adhesion molecule-1 (ICAM-1), IL-4, IL-5, and IL-13 in the BAL fluid. Furthermore, Cor markedly blocked p38-MAPK and nuclear factor-kappaB (NF-κB) signalling pathway activation in the Ova-driven asthmatic mice. In conclusion, this study demonstrated that some of the antiasthmatic benefits of Cor attributable to diets and/or tonics may result from reductions in inflammatory processes and that these antiasthmatic properties involve the inhibition of Th2-type responses through the suppression of the p38-MAPK and NF-κB signalling pathways.