Mitogen-activated protein kinase signaling in childhood asthma development and environment-mediated protection.

BACKGROUND: While childhood asthma prevalence is rising in Westernized countries, farm children are protected. The mitogen-activated protein kinase (MAPK) pathway with its negative regulator dual-specificity phosphatase-1 (DUSP1) is presumably associated with asthma development. OBJECTIVES: We aimed to investigate the role of MAPK signaling in childhood asthma and its environment-mediated protection, including a representative selection of 232 out of 1062 children from two cross-sectional cohorts and one birth cohort study. METHODS: Peripheral blood mononuclear cells (PBMC) from asthmatic and healthy children were cultured upon stimulation with farm-dust extracts or lipopolysaccharide. In subgroups, gene expression was analyzed by qPCR (PBMCs, cord blood) and NanoString technology (dendritic cells). Protein expression of phosphorylated MAPKs was measured by mass cytometry. Histone acetylation was investigated by chromatin immunoprecipitation. RESULTS: Asthmatic children expressed significantly less DUSP1 (p = .006) with reduced acetylation at histone H4 (p = .012) compared with healthy controls. Farm-dust stimulation upregulated DUSP1 expression reaching healthy levels and downregulated inflammatory MAPKs on gene and protein levels (PBMCs; p ≤ .01). Single-cell protein analysis revealed downregulated pMAPKs upon farm-dust stimulation in B cells, NK cells, monocytes, and T-cell subpopulations. CONCLUSION: Lower DUSP1 baseline levels in asthmatic children and anti-inflammatory regulation of MAPK in several immune cell types by farm-dust stimulation indicate a regulatory function for DUSP1 for future therapy contributing to anti-inflammatory characteristics of farming environments.

TNF-α-induced protein 3 is a key player in childhood asthma development and environment-mediated protection.

BACKGROUND: Childhood asthma prevalence is significantly greater in urban areas compared with rural/farm environments. Murine studies have shown that TNF-α-induced protein 3 (TNFAIP3; A20), an anti-inflammatory regulator of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling, mediates environmentally induced asthma protection. OBJECTIVE: We aimed to determine the role of TNFAIP3 for asthma development in childhood and the immunomodulatory effects of environmental factors. METHODS: In a representative selection of 250 of 2168 children from 2 prospective birth cohorts and 2 cross-sectional studies, we analyzed blood cells of healthy and asthmatic children from urban and rural/farm environments from Europe and China. PBMCs were stimulated ex vivo with dust from "asthma-protective" farms or LPS. NF-κB signaling-related gene and protein expression was assessed in PBMCs and multiplex gene expression assays (NanoString Technologies) in isolated dendritic cells of schoolchildren and in cord blood mononuclear cells from newborns. RESULTS: Anti-inflammatory TNFAIP3 gene and protein expression was consistently decreased, whereas proinflammatory Toll-like receptor 4 expression was increased in urban asthmatic patients (P < .05), reflecting their increased inflammatory status. Ex vivo farm dust or LPS stimulation restored TNFAIP3 expression to healthy levels in asthmatic patients and shifted NF-κB signaling-associated gene expression toward an anti-inflammatory state (P < .001). Farm/rural children had lower expression, indicating tolerance induction by continuous environmental exposure. Newborns with asthma at school age had reduced TNFAIP3 expression at birth, suggesting TNFAIP3 as a possible biomarker predicting subsequent asthma. CONCLUSION: Our data indicate TNFAIP3 as a key regulator during childhood asthma development and its environmentally mediated protection. Because environmental dust exposure conferred the anti-inflammatory effects, it might represent a promising future agent for asthma prevention and treatment.

Anti-Inflammatory Activities of Pentaherbs Formula, Berberine, Gallic Acid and Chlorogenic Acid in Atopic Dermatitis-Like Skin Inflammation.

Atopic dermatitis (AD) is a common allergic skin disease, characterized by dryness, itchiness, thickening and inflammation of the skin. Infiltration of eosinophils into the dermal layer and presence of edema are typical characteristics in the skin biopsy of AD patients. Previous in vitro and clinical studies showed that the Pentaherbs formula (PHF) consisting of five traditional Chinese herbal medicines, Flos Lonicerae, Herba Menthae, Cortex Phellodendri, Cortex Moutan and Rhizoma Atractylodis at w/w ratio of 2:1:2:2:2 exhibited therapeutic potential in treating AD. In this study, an in vivo murine model with oxazolone (OXA)-mediated dermatitis was used to elucidate the efficacy of PHF. Active ingredients of PHF water extract were also identified and quantified, and their in vitro anti-inflammatory activities on pruritogenic cytokine IL-31- and alarmin IL-33-activated human eosinophils and dermal fibroblasts were evaluated. Ear swelling, epidermis thickening and eosinophils infiltration in epidermal and dermal layers, and the release of serum IL-12 of the murine OXA-mediated dermatitis were significantly reduced upon oral or topical treatment with PHF (all p < 0.05). Gallic acid, chlorogenic acid and berberine contents (w/w) in PHF were found to be 0.479%, 1.201% and 0.022%, respectively. Gallic acid and chlorogenic acid could suppress the release of pro-inflammatory cytokine IL-6 and chemokine CCL7 and CXCL8, respectively, in IL-31- and IL-33-treated eosinophils-dermal fibroblasts co-culture; while berberine could suppress the release of IL-6, CXCL8, CCL2 and CCL7 in the eosinophil culture and eosinophils-dermal fibroblasts co-culture (all p < 0.05). These findings suggest that PHF can ameliorate allergic inflammation and attenuate the activation of eosinophils.