Atopic dermatitis (AD) is a prevalent inflammatory skin disorder in which patients experience recurrent eczematous lesions and intense itching. The colonization of Staphylococcus aureus (S. aureus) is correlated with the severity of the disease, but its role in AD development remains elusive. Using single-cell RNA sequencing, we uncovered that keratinocytes activate a distinct immune response characterized by induction of Il24 when exposed to methicillin-resistant S. aureus (MRSA). Further experiments using animal models showed that the administration of recombinant IL-24 protein worsened AD-like pathology. Genetic ablation of Il24 or the receptor Il20rb in keratinocytes alleviated allergic inflammation and atopic march. Mechanistically, IL-24 acted through its heterodimeric receptors on keratinocytes and augmented the production of IL-33, which in turn aggravated type 2 immunity and AD-like skin conditions. Overall, these findings establish IL-24 as a critical factor for onset and progression of AD and a compelling therapeutic target.
Dermatitis, Atopic/genetics* ; Interleukins/metabolism* ; Animals ; Methicillin-Resistant Staphylococcus aureus/immunology* ; Mice ; Keratinocytes/microbiology* ; Humans ; Interleukin-33/immunology* ; Inflammation/microbiology* ; Staphylococcal Infections/microbiology* ; Disease Models, Animal ; Hypersensitivity/microbiology* ; Mice, Inbred C57BL

Pseudo-allergic reactions (PARs) widely occur upon application of drugs or functional foods. Anti-pseudo-allergic ingredients from natural products have attracted much attention. This study aimed to investigate anti-pseudo-allergic compounds in licorice. The anti-pseudo-allergic effect of licorice extract was evaluated in rat basophilic leukemia 2H3 (RBL-2H3) cells. Anti-pseudo-allergic compounds were screened by using RBL-2H3 cell extraction and the effects of target components were verified further in RBL-2H3 cells, mouse peritoneal mast cells (MPMCs) and mice. Molecular docking and human MRGPRX2-expressing HEK293T cells (MRGPRX2-HEK293T cells) extraction were performed to determine the potential ligands of MAS-related G protein-coupled receptor-X2 (MRGPRX2), a pivotal target for PARs. Glycyrrhizic acid (GA) and licorice chalcone A (LA) were screened and shown to inhibit Compound48/80-induced degranulation and calcium influx in RBL-2H3 cells. GA and LA also inhibited degranulation in MPMCs and increase of histamine and TNF-α in mice. LA could bind to MRGPRX2, as determined by molecular docking and MRGPRX2-HEK293T cell extraction. Our study provides a strong rationale for using GA and LA as novel treatment options for PARs. LA is a potential ligand of MRGPRX2.
Animals ; Anti-Allergic Agents/therapeutic use* ; Calcium/metabolism* ; Cell Degranulation ; Glycyrrhiza ; HEK293 Cells ; Humans ; Hypersensitivity/drug therapy* ; Mast Cells/metabolism* ; Mice ; Mice, Inbred C57BL ; Molecular Docking Simulation ; Nerve Tissue Proteins/metabolism* ; Rats ; Receptors, G-Protein-Coupled/metabolism* ; Receptors, Neuropeptide/therapeutic use*

The pathophysiology of visceral pain in patients with irritable bowel syndrome remains largely unknown. Our previous study showed that neonatal maternal deprivation (NMD) does not induce visceral hypersensitivity at the age of 6 weeks in rats. The aim of this study was to determine whether NMD followed by adult stress at the age of 6 weeks induces visceral pain in rats and to investigate the roles of adrenergic signaling in visceral pain. Here we showed that NMD rats exhibited visceral hypersensitivity 6 h and 24 h after the termination of adult multiple stressors (AMSs). The plasma level of norepinephrine was significantly increased in NMD rats after AMSs. Whole-cell patch-clamp recording showed that the excitability of dorsal root ganglion (DRG) neurons from NMD rats with AMSs was remarkably increased. The expression of β adrenergic receptors at the protein and mRNA levels was markedly higher in NMD rats with AMSs than in rats with NMD alone. Inhibition of β adrenergic receptors with propranolol or butoxamine enhanced the colorectal distention threshold and application of butoxamine also reversed the enhanced hypersensitivity of DRG neurons. Overall, our data demonstrate that AMS induces visceral hypersensitivity in NMD rats, in part due to enhanced NE-β adrenergic signaling in DRGs.
Adrenergic Agents ; pharmacology ; Animals ; Ganglia, Spinal ; drug effects ; Hyperalgesia ; drug therapy ; physiopathology ; Hypersensitivity ; drug therapy ; Male ; Maternal Deprivation ; Neurons ; drug effects ; Patch-Clamp Techniques ; methods ; Rats, Sprague-Dawley ; Signal Transduction ; drug effects ; Stress, Physiological ; physiology ; Visceral Pain ; chemically induced ; metabolism

Gut microbiota have been known to play an essential role in host immunity and metabolism. Dysbiosis is associated with various gastrointestinal (GI) and other diseases such as cancers, metabolic diseases, allergies, and immunological disorders. So far, the role of gut microbiota has been studied mainly in lower GI disease but has recently been reported in upper GI diseases other than Helicobacter pylori infection, including Barrett's esophagus, esophageal carcinoma, gastric cancer, functional dyspepsia, and non-steroidal anti-inflammatory drug-induced small intestinal mucosal injury. Probiotics have some beneficial effect on these diseases, but the effects are strain specific.
Anti-Inflammatory Agents, Non-Steroidal ; Barrett Esophagus ; Dysbiosis ; Dyspepsia ; Gastrointestinal Diseases ; Gastrointestinal Microbiome ; Helicobacter Infections ; Helicobacter pylori ; Hypersensitivity ; Metabolic Diseases ; Metabolism ; Microbiota ; Probiotics ; Stomach Neoplasms ; Upper Gastrointestinal Tract

Nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity reactions (HSRs) are often nonimmunologically mediated reactions which present with immediate HSR type manifestations. These are mediated by cyclooxygenase inhibition resulting in shunting towards the excessive production of leukotrienes. Important disease associations include asthma, nasal polyposis, and chronic spontaneous urticaria, especially among adults. The European Network on Drug Allergy/Global Allergy and Asthma European Network 2013 classification of NSAID HSR comprises nonselective HSR i.e., NSAID exacerbated respiratory disease (NERD), NSAIDs exacerbated cutaneous disease (NECD), NSAIDs induced urticarial-angioedema (NIUA); and selective (allergic) HSR i.e., single NSAID induced urticaria/angioedema or anaphylaxis, NSAIDs-induced delayed HSR. Much of the literature on genetic associations with NSAID HSR originate from Korea and Japan; where genetic polymorphisms have been described in genes involved in arachidonic acid metabolism, basophil/mast cell/eosinophil activation, various inflammatory mediators/cytokines, and different HLA genotypes. The Asian phenotype for NSAID HSR appears to be predominantly NIUA with overlapping features in some adults and children. NECD also appears to be more common than NERD, although both are not common in the Asian paediatric population. Between adults and children, children seem to be more atopic, although over time when these children grow up, it is likely that the prevalence of atopic adults with NSAID HSR will increase. Low-dose aspirin desensitization has been shown to be effective in the treatment of coronary artery disease, especially following percutaneous coronary intervention.
Adult ; Anaphylaxis ; Anti-Inflammatory Agents, Non-Steroidal ; Arachidonic Acid ; Asian Continental Ancestry Group ; Aspirin ; Asthma ; Child ; Classification ; Coronary Artery Disease ; Drug Hypersensitivity ; Genotype ; Humans ; Hypersensitivity ; Japan ; Korea ; Leukotrienes ; Metabolism ; Percutaneous Coronary Intervention ; Phenotype ; Polymorphism, Genetic ; Prevalence ; Prostaglandin-Endoperoxide Synthases ; Urticaria

OBJECTIVETo investigate the effects of ligustrazine (LTZ) on airway inflammation in a mouse model of neutrophilic asthma (NA).

METHODSForty healthy C57BL/6 female mice were randomly divided into 4 groups using a random number table, including the normal control, NA, LTZ and dexamethasone (DXM) groups, with 10 rats in each group. The NA mice model was established by the method of ovalbumin combined with lipopolysaccharide sensitization. At 0.5 h before each challenge, LTZ and DXM groups were intraperitoneally injected with LTZ (80 mg/kg) or DXM (0.5 mg/kg) for 14 d, respectively, while the other two groups were given the equal volume of normal saline. After last challenge for 24 h, the aerosol inhalation of methacholine was performed and the airway reactivity was measured. The bronchoalveolar lavage fluid (BALF) was collected. The Wright-Giemsa staining was used for total white blood cells and differential counts. The levels of cytokines interleukin (IL)-17 and IL-10 were detected by enzyme-linked immunosorbent assay. The pathological change of lung tissue was observed by hematoxylin eosin staining.

RESULTSThe airway responsiveness of the NA group was signifificantly higher than the normal control group (P<0.05), while those in the LTZ and DXM groups were signifificantly lower than the NA group (P<0.05). The neutrophil and eosinophil counts in the LTZ and DXM groups were signifificantly lower than the NA group (P<0.05), and those in the LTZ group were signifificantly lower than the DXM group (P<0.05). There were a large number of peribronchiolar and perivascular inflammatory cells in fifiltration in the NA group. The airway inflflammation in the LTZ and DXM groups were signifificantly alleviated than the NA group. The infifiltration in the LTZ group was signifificantly reduced than the DXM group. Compared with the normal control group, the IL-17 level in BALF was signifificantly increased and the IL-10 level in BALF was signifificantly decreased in the NA group (P<0.05). LTZ and DXM treatment signifificantly decreased IL-17 levels and increased IL-10 levels compared with the NA group (P<0.05), and the changes in the above indices were more signifificant in the LTZ group (P<0.05).

CONCLUSIONLTZ could alleviate the airway inflflammation in the NA mice model through increasing the IL-10 level and decreasing the IL-17 level.

Animals ; Asthma ; blood ; complications ; drug therapy ; pathology ; Bronchoalveolar Lavage Fluid ; cytology ; Disease Models, Animal ; Female ; Interleukin-10 ; metabolism ; Interleukin-17 ; metabolism ; Leukocyte Count ; Lung ; drug effects ; pathology ; Mice, Inbred C57BL ; Neutrophils ; drug effects ; pathology ; Pneumonia ; blood ; complications ; drug therapy ; pathology ; Pyrazines ; pharmacology ; therapeutic use ; Respiratory Hypersensitivity ; blood ; complications ; drug therapy ; pathology

Recent studies suggest that vitamin D is related to allergic rhinitis (AR). In this review, we first discuss the physiology and metabolism of vitamin D, then we review the function of vitamin D in the immune system, and above all, we highlight the current research regarding the role of vitamin D in AR. Finally, we find that there are both experimental and clinical studies showing that vitamin D is associated with AR, although the results are not consistent and even conflicting. Evidences from those clinical studies show a slightly tendency that serum vitamin D level might be inversely associated with the risk of AR. Meanwhile, it seems that gender and age may influence the relationship between vitamin D and AR. However, because of the heterogeneity in defining AR, differences in study design and so on, all these findings need to be confirmed by further studies. Additional clinical studies as well as experimental research are needed to better understand how vitamin D influences AR.
Hypersensitivity ; Immune System ; Metabolism ; Physiology ; Population Characteristics ; Rhinitis, Allergic ; Vitamin D ; Vitamins

PURPOSE: In addition to regulating calcium and phosphorus homeostasis and bone metabolism, vitamin D is known as an immune modulator. Recently, there has been increased worldwide interest in the association between low levels of vitamin D and allergic diseases. The purpose of this study was to assess the relationship between serum vitamin D levels and allergic/vasomotor rhinitis (AR/VR) in children. METHODS: This study included 164 patients. The sample included 59 patients with AR, 42 patients with VR, and 63 controls. Their ages ranged from 0 to 16 years. We examined the levels of 25-hydroxyvitamin D, Immunoglobulin E, specific IgE, and eosinophil cationic protein; peripheral blood eosinophil count; and the results of a skin prick test. RESULTS: Serum 25-hydroxyvitamin D levels were 19.0+/-8.5 ng/mL in the AR group, 25.5+/-10.9 ng/mL in the VR group, and 26.9+/-10.7 ng/mL in the control group. After adjustment for body mass index and season at the time of blood sampling, vitamin D levels in the AR group were lower than those of the VR group (P=0.003) and control group (P<0.001). Vitamin D levels were inversely correlated with Immunoglobulin E levels (r=-0.317, P<0.001). AR patients with food allergy or atopic dermatitis did not have lower levels of 25-hydroxyvitamin D than AR patients without these diseases. CONCLUSION: This study demonstrates a possible relationship between vitamin D levels and allergic rhinitis in Korean children.
Body Mass Index ; Calcium ; Child* ; Dermatitis, Atopic ; Eosinophil Cationic Protein ; Eosinophils ; Food Hypersensitivity ; Homeostasis ; Humans ; Immunoglobulin E ; Immunoglobulins ; Metabolism ; Phosphorus ; Rhinitis ; Rhinitis, Vasomotor* ; Seasons ; Skin ; Vitamin D* ; Vitamins*

Child ; Humans ; Hypersensitivity ; Vitamin D ; metabolism ; Vitamin D Deficiency ; Vitamins ; metabolism

To explore the relationship between the epithelial adhesion molecules and immune responses of airway epithelium, we observed the expression of integrin β4 and intercellular adhesion molecule-1 (ICAM-1) in the mice airway epithelium after sensitization with allergens. BALB/c mice were sensitized with intraperitoneal injection of ovalbumin (OVA) or house dust mite (HDM) and then developed airway hyper-responsiveness as determined by barometric whole-body plethysmography. Both OVA and HDM sensitization led to increases of the number of peripheral leukocytes as well as inflammatory cells infiltration in lungs. OVA sensitized mice showed more severe inflammatory cells infiltration than HDM sensitized mice. Immunohistochemistry analysis of mice lung tissues revealed that sensitization with both allergens also led to a decrease of integrin β4 expression and an increase of ICAM-1 expression in airway epithelia. OVA sensitized mice showed a more significant increase of ICAM-1 expression compared with HDM sensitized mice. siRNA mediated silencing of integrin β4 gene in 16HBE cells resulted in an up-regulation of ICAM-1 expression. Our results indicate a possible role of airway epithelial adhesion molecules in allergen-induced airway immune responses.
Allergens ; pharmacology ; Animals ; Integrin beta4 ; metabolism ; Intercellular Adhesion Molecule-1 ; metabolism ; Lung ; metabolism ; physiopathology ; Mice ; Mice, Inbred BALB C ; Ovalbumin ; Pyroglyphidae ; Respiratory Hypersensitivity ; metabolism