Role of inflammatory lipid and fatty acid metabolic abnormalities induced by plastic additives exposure in childhood asthma

Lipid metabolism play an essential role in occurrence and development of asthma, and it can be disturbed by phthalate esters (PAEs) and organophosphate flame retardants (OPFRs). As a chronic inflammatory respiratory disease, the occurrence risk of childhood asthma is increased by PAEs and OPFRs exposure, but it remains not entirely clear how PAEs and OPFRs contribute the onset and progress of the disease. We have profiled the serum levels of PAEs and OPFRs congeners by liquid chromatography coupled with mass spectrometry, and its relationships with the dysregulation of lipid metabolism in asthmatic, bronchitic (acute inflammation) and healthy (non-inflammation) children. Eight PAEs and nine OPFRs congeners were found in the serum of children (1 - 5 years old) from Shenzhen, and their total median levels were 615.16 ng/mL and 17.06 ng/mL, respectively. Moreover, the serum levels of mono-methyl phthalate (MMP), tri-propyl phosphate (TPP) and tri-n-butyl phosphate (TNBP) were significant higher in asthmatic children than in healthy and bronchitic children as control. Thirty-one characteristic lipids and fatty acids of asthma were screened by machine-learning random forest model based on serum lipidome data, and the alterations of inflammatory characteristic lipids and fatty acids including palmitic acids, 12,13-DiHODE, 14,21-DiHDHA, prostaglandin D2 and LysoPA(18:2) showed significant correlated with high serum levels of MMP, TPP and TNBP. These results imply PAEs and OPFRs promote the occurrence of childhood asthma via disrupting inflammatory lipid and fatty acid metabolism, and provide a novel sight for better understanding the effects of plastic additives on childhood asthma.

Association of Interleukin-4 Receptor α Chain I50V Gene Variant (rs1805010) and Asthma in Iranian Population: A Case-control Study

Background

Asthma is one of the respiratory disorders caused by chronic airway inflammation. IL-4 has been identified as one of the participating interleukins in the severity of asthma.

Objective

A case-control study was conducted to determine the association of rs1805010, a single nucleotide polymorphism in the interleukin 4 receptor α chain, with asthma and immunoglobulin E and IL-17A serum levels in Iranian populations.

Methods

ELISA was used to investigate the relationship between three different varieties of SNP I50V and serum IL-17A levels, as well as total IgE levels. Based on GINA criteria, patients were classified into mild, moderate, and severe groups based on the association between SNP I50V, IL-17A, and total IgE. In order to analyze the data, the student-t-test and the one-way ANOVA were used.

Results

The SNP I50V was associated with asthma in a significant way (p = 0.001). IL-17A and total IgE levels were significantly higher in asthmatic patients than in control participants (p 0.05 and p 0.021, respectively), but neither showed any association with SNP I50V in the asthmatic patients.

Conclusion

Asthma patients have a higher prevalence of the I allele, reflecting the significance of Th2 cells. Although total IgE and IL-17A levels increased in both disease subgroups, total IgE level augmentation correlates directly with disease severity, while IL-17A level enhancement does not.

Management of Chronic Asthma in Adults

Asthma is characterized by chronic inflammation and respiratory symptoms such as wheezing and coughing. In the United States, it affects 25 million people annually. Chronic smokers, poor adherence to medications, incorrect use of inhalers, and overall poor asthma control are known risk factors that lead to poorly controlled chronic asthmatics. Although asthma is traditionally categorized by severity, treatment by primary care providers is guided by the Global Initiative for Asthma or the National Asthma Education and Prevention Program. As more research is available, shared decision-making between health care providers and patients will lead to improved outcomes in managing chronic asthma.

Apolipoprotein E negatively regulates allergic airway inflammation and remodeling in mice with OVA-induced chronic asthma

Apolipoprotein E (ApoE) is a corticosteroid-unresponsive gene that negatively regulates ovalbumin (OVA) -induced allergic airway inflammation in mice with acute asthma. However, whether ApoE negatively regulates airway remodeling in mice with OVA-induced chronic asthma remains unknown. This study aimed to investigate the effects of ApoE on OVA-induced chronic asthma in a murine model. ApoE knockout (ApoE^-/-) and wild-type (WT) mice were sensitized and challenged with OVA for 10 weeks to establish the chronic asthma model. Compared with WT mice, the results demonstrated that ApoE deficiency exacerbated OVA-induced airway inflammation, including elevated numbers of inflammatory cells in the blood and bronchoalveolar lavage fluid (BALF), as well as increased T helper type 2 (Th2) cells in lung tissue, Th2 cytokines in BALF, and total IgE levels in plasma. Importantly, ApoE deficiency aggravated OVA-induced airway remodeling, as evidenced by higher plasma transforming growth factor (TGF)-β1 levels, airway goblet cell hyperplasia, and collagen deposition compared with WT mice. These results revealed that ApoE deficiency aggravates airway remodeling and inflammation in mice with OVA-induced chronic allergic asthma.

The endogenous cannabinoid anandamide increases human airway epithelial cell permeability through an arachidonic acid metabolite

Injury to the bronchial epithelium in respiratory diseases such as asthma and COPD results in the loss of barrier function and an elevated sensitivity to environmental insults. An increased release of the endogenous cannabinoid, anandamide in response to inhalation of allergen in asthmatic patients has been reported. The aim of this study was, therefore, to determine the effects of endocannabinoids on bronchial epithelial cell permeability and to investigate the mechanisms involved. Calu-3 human bronchial epithelial cells were cultured at air-liquid interface to allow development of tight junctions. Changes in Transepithelial Electrical Resistance (TEER), a reflection of epithelial permeability, were measured at various time points post-treatment, and expression of the tight junction proteins, occludin and ZO-1, were determined using Western immunoblotting. Anandamide produced a significant reduction in TEER, which was unaffected by cannabinoid receptor antagonists, but attenuated by URB597, an inhibitor of fatty acid amide hydrolase, and by a combination of cyclooxygenase (COX) and lipoxygenase (LOX) blockade. The anandamide metabolite, arachidonic acid, showed similar TEER decrease that was also prevented in the presence of COX and LOX inhibitor. Expression of occludin and ZO-1 were also reduced by anandamide. These findings indicate a pro-inflammatory-like effect of anandamide on bronchial epithelial permeability, mediated by cyclooxygenase and lipoxygenase metabolites, and suggest that inhibition of anandamide degradation might provide a novel approach to treat airway inflammation.

Bu-Shen-Yi-Qi formulae suppress chronic airway inflammation and regulate Th17/Treg imbalance in the murine ovalbumin asthma model

ETHNOPHARMACOLOGICAL RELEVANCE

Bu-Shen-Yi-Qi formulae (BSYQF) are frequently used in the treatment of chronic inflammatory diseases in the respiratory system in traditional Chinese medicine (TCM). However, the regulatory effect of BSYQF on T helper 17 (Th17) and regulatory T (Treg) cells in murine ovalbumin (OVA) asthma model remains poorly understood. In the present study, we sought to determine the effect of high-performance liquid chromatography/mass spectrometry (HPLC/MS) standardized BSYQF on chronic airway inflammation and Th17/Treg imbalance in the murine OVA asthma model.

MATERIALS AND METHODS

The murine asthma model was induced by OVA sensitization and challenge and BSYQF was oral administrated. 24h after last OVA exposure, airway hyperresponsiveness (AHR) to methacholine (Mch) was assessed, and inflammatory cell counts and classification in bronchoalveolar lavage fluid (BALF) were analysed. Histopathological evaluation of the lung tissue was performed by hematoxylin and eosin (H&E) and periodic acid-Schiff (PAS) staining. Th17 and Treg associated cytokine levels in serum and BALF as well as transcription factors expression in the lung tissue were measured by ELISA, Bio-Plex and western blot assay. We also analysed the CD4(+)RORγt(+) and CD4(+)Foxp3(+) T cells in BALF and spleen by flow cytometric analysis.

RESULTS

Our results demonstrated that oral administration of BSYQF inhibited the markedly increased AHR and lung inflammation (p<0.05), resulted in a dramatic reduction in total inflammatory cells as well as neutrophils (Neu), lymphocytes (Lym), monocytes (Mon), eosinophils (Eos) and basophils (Bas) of OVA-induced asthmatic mice (p<0.05). Furthermore, BSYQF treatment caused a distinct reduction in IL-6, IL-10 and IL-17A levels in serum (p<0.05), and induced a significant improvement in IL-6 and IL-10 as well as a marked decrease in TGF-β1 and IL-17A levels in BALF of OVA-induced asthmatic mice (p<0.05). Mice in BSYQF treated groups also had decreased RORγt and increased Foxp3 expression in the lung tissue (p<0.05). Flow cytometry analysis revealed that CD4(+)RORγt(+) T cells elevated markedly and CD4(+)Foxp3(+) T cells decreased prominently in BALF and spleen in murine OVA asthma model (p<0.05), and BSYQF and DEX treatment lead to an obvious reduction in CD4(+)RORγt(+) T cells in BALF (p<0.05) but not in spleen. BSYQF and DEX treatment resulted in an obvious elevation in CD4(+)Foxp3(+) T cells in BALF and spleen (p<0.05).

CONCLUSIONS

Collectively, these results demonstrated that BSYQF could suppress chronic airway inflammation and regulate Th17/Treg imbalance by inhibition of Th17 and enhancement of Treg functions in the murine OVA asthma model, which may help to elucidate the underlying regulatory mode of BSYQF on asthma treatment.