Modulation by flunisolide of tumor necrosis factor-alpha-induced stimulation of airway epithelial cell activities related to eosinophil inflammation

Efficacy of Trigonella foenum-graecum Linné in an animal model of particulate matter-induced asthma exacerbation

ETHNOPHARMACOLOGICAL RELEVANCE

The seeds of Trigonella foenum-graecum Linné (TFG) has traditionally been used in Central Asia to relieve inflammation.

AIM OF THE STUDY

This study investigated the efficacy of TFG in a bronchial cell model and an animal model of asthma exacerbation caused by PM.

METHODS

BEAS-2B bronchial epithelial cells were simultaneously treated with tumor necrosis factor-α/interleukin (IL)-4 and PM, and the expression of inflammatory cytokines, DNA damage, and autophagy mechanisms were analyzed. In an animal model of asthma exacerbation, we analyzed changes in organ weight, distribution of inflammatory cytokines and inflammatory cells in the bronchoalveolar lavage fluid, and intra-tissue mucus production.

RESULTS

In the cell model, TFG suppressed the expression of the inflammatory cytokines IL-6, granulocyte-macrophage colony stimulating factor, monocyte chemoattractant protein-1, and IL-8; reactive oxygen species levels and DNA damage; and the phosphorylation of ERK, JNK, P38, AKT, and mTOR. In the animal model, TFG significantly reduced weight gain of the liver, lung, and spleen; IgE, IL-6, and IFN-γ levels; and bronchial mucus secretion and smooth muscle thickness.

CONCLUSION

TFG alleviated the PM-exacerbated inflammatory response by inhibiting the MAPK and autophagy signaling pathways; it is expected to be an effective treatment for asthma.

Airway epithelial cell-specific delivery of lipid nanoparticles loading siRNA for asthma treatment

With specific and inherent mRNA cleaving activity, small interfering RNA (siRNA) has been deemed promising therapeutics to reduce the exacerbation rate of asthma by inhibiting the expression and release of proinflammatory cytokines from airway epithelial cells (AECs). To exert the therapeutic effects of siRNA drugs, nano-formulations with high efficiency and safety are required to deliver these nucleic acids to the target cells. Herein, we exploited novel inhaled lipid nanoparticles (LNPs) targeting intercellular adhesion molecule-1 (ICAM-1) receptors on the apical side of AECs. This delivery system is meant to enhance the specific delivery efficiency of siRNA in AECs to prevent the expression of proinflammatory cytokines in AECs and the concomitant symptoms in parallel. A cyclic peptide that resembles part of the capsid protein of rhinovirus and binds to ICAM-1 receptors was initially conjugated with cholesterol and subsequently assembled with ionizable cationic lipids to form the LNPs (Pep-LNPs) loaded with siRNA against thymic stromal lymphopoietin (TSLP siRNA). The obtained Pep-LNPs were subjected to thorough characterization and evaluations in vitro and in vivo. Pep-LNPs significantly enhanced cellular uptake and gene silencing efficiency in human epithelial cells expressing ICAM-1 in vitro, exhibited AEC-specific delivery and improved the gene silencing effect in ovalbumin-challenged asthmatic mice after pulmonary administration. More importantly, Pep-LNPs remarkably downregulated the expression of TSLP in AECs, effectively alleviated inflammatory cell infiltration, and reduced the secretion of other proinflammatory cytokines, including IL-4 and IL-13, as well as mucus production in asthmatic mice. This study demonstrates that Pep-LNPs are safe and efficient to deliver siRNA drugs to asthmatic AECs and could potentially alleviate allergic asthma by inhibiting the overexpression of proinflammatory cytokines in the airway.

Anti-inflammatory effects of Salvia plebeia R. Br extract in vitro and in ovalbumin-induced mouse model

BACKGROUND

Asthma is an increasing global health problem, and novel strategies to prevent or ameliorate the condition are needed. Here, the effects of 80 % ethanol extracts of Salvia plebeia R. Br. (SE) on an induced inflammatory response were investigated.

RESULTS

Salvia plebeia R. Br. inhibited production of pro-inflammatory cytokines, such as TNF-α and IL-6, as well as nitric oxide (NO) in LPS-stimulated RAW 264.7 cells. NO and pro-inflammatory cytokine production was suppressed more effectively by SE of the aerial parts (SE-A) than of the roots (SE-R) of S. plebeia. In BEAS-2B cells, both SE-A and SE-R inhibited the increase in production of the inflammatory cytokines IL-6 and IL-8. We also investigated the anti-asthmatic effects of SE in an ovalbumin (OVA)-induced BALB/c mouse model. SE-A treatment significantly reduced the number of airway eosinophils, IL-4 and IL-13 levels, mucus production, and inflammatory infiltration, as compared with the corresponding levels in the untreated, OVA-induced mice, and had similar effects to dexamethasone.

CONCLUSIONS

Salvia plebeia ethanol extract ameliorated the induced inflammatory response in RAW 264.7 and BEAS-2B cells, with more effective inhibition noted for SE-A than for SE-R. SE-A treatment was effective in improving the histopathological changes in the lungs of asthma model mice via modulation of eosinophils and Th2 cytokines. These results suggest that SE-A can be considered as a therapeutic agent that can potentially relieve asthma.

Sputum Leucine-Rich Alpha-2 Glycoprotein as a Marker of Airway Inflammation in Asthma

Background

Asthma is a chronic inflammatory disease of airways, but an ideal biomarker that accurately reflects ongoing airway inflammation has not yet been established. The aim of this study was to examine the potential of sputum leucine-rich alpha-2 glycoprotein (LRG) as a new biomarker for airway inflammation in asthma.

Methods

We obtained induced sputum samples from patients with asthma (N = 64) and healthy volunteers (N = 22) and measured LRG concentration by sandwich enzyme-linked immunosorbent assay (ELISA). Ovalbumin (OVA)-induced asthma model mice were used to investigate the mechanism of LRG production during airway inflammation. The LRG concentrations in the bronchoalveolar lavage fluid (BALF) obtained from mice were determined by ELISA and mouse lung sections were stained with anti-LRG antibody and periodic acid-Schiff (PAS) reagent.

Results

Sputum LRG concentrations were significantly higher in patients with asthma than in healthy volunteers (p = 0.00686). Consistent with patients’ data, BALF LRG levels in asthma model mice were significantly higher than in control mice (p = 0.00013). Immunohistochemistry of lung sections from asthma model mice revealed that LRG was intensely expressed in a subpopulation of bronchial epithelial cells, which corresponded with PAS-positive mucus producing cells.

Conclusion

These findings suggest that sputum LRG is a promising biomarker of local inflammation in asthma.

Ribes fasciculatum var. chinense Attenuated Allergic Inflammation In Vivo and In Vitro

Ribes fasciculatum var. chinense MAX. (R. fasciculatum) has traditionally been used in Korea to treat inflammatory diseases. However, the exact mechanism that accounts for the anti-inflammatory effect of R. fasciculatum is not completely understood. We aimed to ascertain the pharmacological effects of R. fasciculatum on both compound 48/80- or histamine-induced scratching behaviors and 2, 4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) in mice. Additionally, to find a possible explanation for the anti-inflammatory effects of R. fasciculatum, we evaluated the effects of R. fasciculatum on the production of inflammatory mediators in LPS-stimulated macrophage cells. Treatment of R. fasciculatum significantly reduced compound 48/80- or histamine-induced the pruritus in mice. R. fasciculatum attenuated the AD symptoms such as eczematous, erythema and dryness and serum IgE levels in AD model. Additionally, R. fasciculatum inhibited the production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). The maximal rates of TNF-α and IL-6 inhibition by R. fasciculatum (1 mg/ml) were approximately 32.12% and 46.24%, respectively. We also showed that R. fasciculatum inhibited the activation of nuclear factor-kappa B in LPS-stimulated macrophages. Collectively, the findings of this study provide us with novel insights into the pharmacological actions of R. fasciculatum as a potential molecule for use in the treatment of allergic inflammatory diseases.