IL-4/IL-13 Axis in Allergic Rhinitis: Elevated Serum Cytokines Levels and Inverse Association With Tight Junction Molecules Expression

15-Hydroxyeicosatrienoic acid induces nasal congestion by changing vascular functions in mice

BACKGROUND

Nasal congestion in allergic rhinitis (AR) is caused by vascular hyperpermeability and vascular relaxation of the nasal mucosa. We previously detected high levels of a lipoxygenation metabolite of dihomogammalinolenic acid, 15-hydroxy-8Z,11Z,13E-eicosatrienoic acid (15-HETrE) in the nasal lavage fluid of AR model mice. Here, we investigated the effects of 15-HETrE on vascular functions associated with nasal congestion.

METHODS

We measured 15-HETrE levels in the nasal lavage fluid of ovalbumin-induced AR model mice and nasal discharge of patients with AR. We also assessed nasal congestion and vascular relaxation in mice. Vascular contractility was investigated using isolated mouse aortas.

RESULTS

Five ovalbumin challenges increased 15-HETrE levels in AR model mice. 15-HETrE was also detected in patients who exhibiting AR-related symptoms. Intranasal administration of 15-HETrE elicited dyspnea-related behavior and decreased the nasal cavity volume in mice. Miles assay and whole-mount immunostaining revealed that 15-HETrE administration caused vascular hyperpermeability and relaxation of the nasal mucosa. Intravital imaging demonstrated that 15-HETrE relaxed the ear vessels that were precontracted via thromboxane receptor stimulation. Moreover, 15-HETrE dilated the isolated mouse aortas, and this effect was attenuated by K+ channel inhibitors and prostaglandin D2 (DP) and prostacyclin (IP) receptor antagonists. Additionally, vasodilatory effects of 15-HETrE were accompanied by an increase in intracellular cAMP levels.

CONCLUSIONS

Our results indicate that 15-HETrE, whose levels are elevated in the nasal cavity upon AR, can be a novel lipid mediator that exacerbates nasal congestion. Moreover, it can stimulate DP and IP receptors and downstream K+ channels to dilate the nasal mucosal vasculature.

Identifying allergic-rhinitis-associated genes with random-walk-based method in PPI network

Allergic rhinitis is a common allergic disease with a complex pathogenesis and many unresolved issues. Studies have shown that the incidence of allergic rhinitis is closely related to genetic factors, and research on the related genes could help further understand its pathogenesis and develop new treatment methods. In this study, 446 allergic rhinitis-related genes were obtained on the basis of the DisGeNET database. The protein-protein interaction network was searched using the random-walk-with-restart algorithm with these 446 genes as seed nodes to assess the linkages between other genes and allergic rhinitis. Then, this result was further examined by three screening tests, including permutation, interaction, and enrichment tests, which aimed to pick up genes that have strong and special associations with allergic rhinitis. 52 novel genes were finally obtained. The functional enrichment test confirmed their relationships to the biological processes and pathways related to allergic rhinitis. Furthermore, some genes were extensively analyzed to uncover their special or latent associations to allergic rhinitis, including IRAK2 and MAPK, which are involved in the pathogenesis of allergic rhinitis and the inhibition of allergic inflammation via the p38-MAPK pathway, respectively. The new found genes may help the following investigations for understanding the underlying molecular mechanisms of allergic rhinitis and developing effective treatments.

Silenced LASP1 interacts with DNMT1 to promote TJP2 expression and attenuate articular cartilage injury in mice by suppressing TJP2 methylation

To investigate the regulatory mechanisms and effects of LIM and SH3 protein 1 (LASP1) on osteoarthritis (OA). IL-1β was used to induce OA in cell models. Viability and apoptosis of chondrocytes were assessed. The expressions of tumor necrsis factor-α (TNF-α) and IL-6 were measured by ELISA kit, and Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot were performed to test the expression of related proteins. The STRING database was used to predict the relationship between LASP1 and DNA methyltransferase 1 (DNMT1). The tight junction protein 2 (TJP2) and Gene Expression Omnibus data were analyzed for differential OA genes. Methylation-specific PCR detected methylation of the TJP2 promoter region, and chromatin immunoprecipitation detected the enrichment of DNMT1 in the TJP2 promoter region. Safranin O-Fast Green staining and hematoxylin and eosin staining were used to determine the OARSI score and evaluate the pathological conditions of the joint tissues. LASP1 was highly expressed in IL-1β-induced cell models. Silencing of LASP1 promoted chondrocyte proliferation and expression of Collagen II and Aggrecan and inhibited chondrocyte apoptosis, inflammatory factors, and matrix metalloprotein expression. TJP2 is weakly expressed in OA models, and LASP1 promotes methylation of the TJP2 promoter region by interacting with DNMT1. Silencing of LASP1 attenuated IL-1β-induced chondrocyte degeneration by promoting TJP2 expression. Similarly, silencing LASP1 promotes TJP2 expression to alleviate articular cartilage injury in mice with OA. Silencing of LASP1 inhibited the methylation of the TJP2 promoter region by interacting with DNMT1, thereby alleviating articular cartilage damage in OA mice.

Exploring the latest understanding on the role of immune mediators, genetic and environmental factors in pathogenesis of allergic rhinitis: a systematic review

Introduction

Despite well-defined clinical phenotypes of chronic rhinitis, the underlying in-depth pathophysiological mechanism, particularly with reference to the involvement of immune mediators, genetic, and environmental factors, are still not fully understood. Therefore, our aim was to give updated information on the pathogenesis of allergic rhinitis (AR), with an emphasis on the role of cytokines in adults aged 18 years and above. Additionally, we investigated the impact of genetic and environmental factors in the pathogenesis of AR.

Results

A search in various databases identified 1,178 records, and 18 studies were ultimately selected from January 2018 to April 2023. The total sample size in our studies was 4,317, with 2,186 in the experimental and 2,131 in control groups, respectively. The mean age was 33.4 years, with 43% were male, while 57% were female. According to the selected studies, various factors, including immune mediators, particularly cytokines, genetic, and environmental factors, were identified in the development of AR.

Conclusion

The selected studies presented findings on different factors and sub-factors in the pathogenesis of AR, making it a challenge for us to compare their results. However, based on our findings, researchers can link our identified factors to potential therapies for AR.

Claudin-4: A New Molecular Target for Epithelial Cancer Therapy

Claudin-4 (CLDN4) is a key component of tight junctions (TJs) in epithelial cells. CLDN4 is overexpressed in many epithelial malignancies and correlates with cancer progression. Changes in CLDN4 expression have been associated with epigenetic factors (such as hypomethylation of promoter DNA), inflammation associated with infection and cytokines, and growth factor signaling. CLDN4 helps to maintain the tumor microenvironment by forming TJs and acts as a barrier to the entry of anticancer drugs into tumors. Decreased expression of CLDN4 is a potential marker of epithelial-mesenchymal transition (EMT), and decreased epithelial differentiation due to reduced CLDN4 activity is involved in EMT induction. Non-TJ CLDN4 also activates integrin beta 1 and YAP to promote proliferation, EMT, and stemness. These roles in cancer have led to investigations of molecular therapies targeting CLDN4 using anti-CLDN4 extracellular domain antibodies, gene knockdown, clostridium perfringens enterotoxin (CPE), and C-terminus domain of CPE (C-CPE), which have demonstrated the experimental efficacy of this approach. CLDN4 is strongly involved in promoting malignant phenotypes in many epithelial cancers and is regarded as a promising molecular therapeutic target.

IL-4/IL-13 axis as therapeutic targets in allergic rhinitis and asthma

Allergic rhinitis (AR) is a common disorder of the upper airway, while asthma is a disease affecting the lower airway and both diseases are usually comorbid. Interleukin (IL)-4 and IL-13 are critical cytokines in the induction of the pathogenic Th2 responses in AR and asthma. Targeting the IL-4/IL-13 axis at various levels of its signaling pathway has emerged as promising targeted therapy in both AR and asthma patient populations. In this review, we discuss the biological characteristics of IL-4 and IL-13, their signaling pathways, and therapeutic antibodies against each cytokine as well as their receptors. In particular, the pleiotropic roles of IL-4 and IL-13 in orchestrating Th2 responses in AR and asthma patients indicate that dual IL-4/IL-13 blockade is a promising therapeutic strategy for both diseases.

Allergic Rhinitis: A Clinical and Pathophysiological Overview

Allergic rhinitis (AR) represents a global health concern where it affects approximately 400 million people worldwide. The prevalence of AR has increased over the years along with increased urbanization and environmental pollutants thought to be some of the leading causes of the disease. Understanding the pathophysiology of AR is crucial in the development of novel therapies to treat this incurable disease that often comorbids with other airway diseases. Hence in this mini review, we summarize the well-established yet vital aspects of AR. These include the epidemiology, clinical and laboratory diagnostic criteria, AR in pediatrics, pathophysiology of AR, Th2 responses in the disease, as well as pharmacological and immunomodulating therapies for AR patients.