Impact of cigarette smoke and IL-17A activation on asthmatic patients with chronic rhinosinusitis

Effects and mechanisms of polycyclic aromatic hydrocarbons in inflammatory skin diseases

Polycyclic aromatic hydrocarbons (PAHs) are hydrocarbons characterized by the presence of multiple benzene rings. They are ubiquitously found in the natural environment, especially in environmental pollutants, including atmospheric particulate matter, cigarette smoke, barbecue smoke, among others. PAHs can influence human health through several mechanisms, including the aryl hydrocarbon receptor (AhR) pathway, oxidative stress pathway, and epigenetic pathway. In recent years, the impact of PAHs on inflammatory skin diseases has garnered significant attention, yet many of their underlying mechanisms remain poorly understood. We conducted a comprehensive review of articles focusing on the link between PAHs and several inflammatory skin diseases, including psoriasis, atopic dermatitis, lupus erythematosus, and acne. This review summarizes the effects and mechanisms of PAHs in these diseases and discusses the prospects and potential therapeutic implications of PAHs for inflammatory skin diseases.

COX-2/sEH-Mediated Macrophage Activation Is a Target for Pulmonary Protection in Mouse Models of Chronic Obstructive Pulmonary Disease

Effective inhibition of macrophage activation is critical for resolving inflammation and restoring pulmonary function in patients with chronic obstructive pulmonary disease (COPD). In this study, we identified the dual-enhanced cyclooxygenase-2 (COX-2)/soluble epoxide hydrolase (sEH) as a novel regulator of macrophage activation in COPD. Both COX-2 and sEH were found to be increased in patients and mice with COPD and in macrophages exposed to cigarette smoke extract. Pharmacological reduction of the COX-2 and sEH by 4-(5-phenyl-3-{3-[3-(4-trifluoromethylphenyl)-ureido]-propyl}-pyrazol-1-yl)-benzenesulfonamide (PTUPB) effectively prevented macrophage activation, downregulated inflammation-related genes, and reduced lung injury, thereby improving respiratory function in a mouse model of COPD induced by cigarette smoke and lipopolysaccharide. Mechanistically, enhanced COX-2/sEH triggered the activation of the NACHT, LRR, and PYD domains-containing protein 3 inflammasome, leading to the cleavage of pro-IL-1β into its active form in macrophages and amplifying inflammatory responses. These findings demonstrate that targeting COX-2/sEH-mediated macrophage activation may be a promising therapeutic strategy for COPD. Importantly, our data support the potential use of the dual COX-2 and sEH inhibitor PTUPB as a therapeutic drug for the treatment of COPD.

Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is an inflammatory disease of paranasal sinuses. This study is formulated to explore the roles of pro-inflammatory factors Chemerin and interleukin-17 (IL-17) in CRS. Patients suffering from CRS without/with nasal polyps (CRSsNP/CRSwNP), along with volunteers, were recruited. CRS rabbit models were constructed by Staphylococcus aureus infection and rabbits were injected with lentiviral vectors of short hairpin RNA-targeting Chemerin (shChemerin), followed by micro-computed tomography (CT) scan. Levels of Chemerin and IL-17 were determined, and histopathological lesions were observed in subjects and CRS rabbits. Correlations between Chemerin/IL-17 level and Lund-Mackay/Lund-Kennedy scores of subjects and the predictive value of Chemerin or IL-17 for CRS were analyzed. In CRS patients and rabbits, inflammatory degrees and the level of Chemerin/IL-17 were increased in pathological tissues or plasma, while Chemerin silencing alleviated CRS symptoms of CRS rabbits. Chemerin and IL-17 were mainly located in the immune cells of pathological tissues and presented the positive correlation with Lund-Mackay/Lund-Kennedy score of CRS patients. Also, they showed high predictive value for CRS. Micro-CT scan uncovered that CRS rabbits had increased bone remodeling, which was alleviated by Chemerin silencing. Collectively, Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis.

Tissue-resident innate lymphoid cells in asthma

Asthma is a chronic airway inflammatory disease whose global incidence increases annually. The role of innate lymphoid cells (ILCs) is a crucial aspect of asthma research with respect to different endotypes of asthma. Based on its pathological and inflammatory features, asthma is divided into type 2 high and type 2 low endotypes. Type-2 high asthma is distinguished by the activation of type 2 immune cells, including T helper 2 (Th2) cells and ILC2s; the production of cytokines interleukin (IL)-4, IL-5 and IL-13; eosinophilic aggregation; and bronchial hyper-responsiveness. Type-2 low asthma represents a variety of endotypes other than type 2 high endotype such as the IL-1β/ILC3/neutrophil endotype and a paucigranulocytic asthma, which may be insensitive to corticosteroid treatment and/or associated with obesity. The complexity of asthma is due to the involvement of multiple cell types, including tissue-resident ILCs and other innate immune cells including bronchial epithelial cells, dendritic cells, macrophages and eosinophils, which provide immediate defence against viruses, pathogens and allergens. On this basis, innate immune cells and adaptive immune cells combine to induce the pathological condition of asthma. In addition, the plasticity of ILCs increases the heterogeneity of asthma. This review focuses on the phenotypes of tissue-resident ILCs and their roles in the different endotypes of asthma, as well as the mechanisms of tissue-resident ILCs and other immune cells. Based on the phenotypes, roles and mechanisms of immune cells, the therapeutic strategies for asthma are reviewed.

Expression of Major Lipid Raft Protein Raftlin in Chronic Rhinosinusitis with Nasal Polyps in Smoking and Non-Smoking Patients Correlated with Interleukin-17 and Tumor Necrosis Factor-α Levels

Raftlin, as an inflammatory biomarker, has been previously reported in chronic inflammatory diseases. This study investigates the expression of Raftlin in cigarette smokers and in chronic rhinosinusitis with nasal polyps (CRSwNP), as well as evaluating its correlation with interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) levels. A total of 30 CRSwNP non-smoking and 16 CRSwNP + SK (smoking) patients undergoing endoscopic sinus surgery were enrolled, while 20 middle turbinate tissue pieces were examined and performed as the control group. In nasal mucosa epithelial staining, Raftlin levels were elevated in the columnar cells and were stained much more intensely in the CRSwNP and CRSwNP + SK groups. Raftlin was located more closely to the apical region of the epithelium in the CRSwNP + SK group; however, the Raftlin levels from whole nasal tissue pieces, according to ELISA data, showed that there was no significant difference between the three different study groups. A positive relationship by Pearson correlation was found between IL-17 or TNF-α levels and Raftlin levels. Taken together, these data indicate that increasing Raftlin expression in columnar cells might involve nasal epithelial remodeling in smokers with CRSwNP.

Rhinology in review: from COVID-19 to biologicals

We look back at the end of what soon will be seen as an historic year, from COVID-19 to real-world introduction of biologicals influencing the life of our patients. This review describes the important findings in Rhinology over the past year. A large body of evidence now demonstrates loss of sense of smell to be one of the most common symptoms of COVID-19 infection; a meta-analysis of 3563 patients found the mean prevalence of self-reported loss to be 47%. A number of studies have now shown long-term reduced loss of smell and parosmia. Given the high numbers of people affected by COVID-19, even with the best reported recovery rates, a significant number worldwide will be left with severe olfactory dysfunction. The most prevalent causes for olfactory dysfunction, besides COVID-19 and upper respiratory tract infections in general, are trauma and CRSwNP. For these CRSwNP patients a bright future seems to be starting with the development of treatment with biologics. This year the Nobel prize in Medicine 2021 was awarded jointly to David Julius and Ardem Patapoutian for their discoveries of receptors for temperature and touch which has greatly enhanced our understanding of nasal hyperreactivity and understanding of intranasal trigeminal function. Finally, a new definition of chronic rhinitis has been proposed in the last year and we have seen many papers emphasizing the importance of endotyping patients in chronic rhinitis and rhinosinusitis in order to optimise treatment effect.

Acetaminophen-Induced Liver Injury Exposes Murine IL-22 as Sex-Related Gene Product

Gaining detailed knowledge about sex-related immunoregulation remains a crucial prerequisite for the development of adequate disease models and therapeutic strategies enabling personalized medicine. Here, the key parameter of the production of cytokines mediating disease resolution was investigated. Among these cytokines, STAT3-activating interleukin (IL)-22 is principally associated with recovery from tissue injury. By investigating paradigmatic acetaminophen-induced liver injury, we demonstrated that IL-22 expression is enhanced in female mice. Increased female IL-22 was confirmed at a cellular level using murine splenocytes stimulated by lipopolysaccharide or αCD3/CD28 to model innate or adaptive immunoactivation. Interestingly, testosterone or dihydrotestosterone reduced IL-22 production by female but not by male splenocytes. Mechanistic studies on PMA/PHA-stimulated T-cell-lymphoma EL-4 cells verified the capability of testosterone/dihydrotestosterone to reduce IL-22 production. Moreover, we demonstrated by chromatin immunoprecipitation that testosterone impairs binding of the aryl hydrocarbon receptor to xenobiotic responsive elements within the murine IL-22 promoter. Overall, female mice undergoing acute liver injury and cultured female splenocytes upon inflammatory activation display increased IL-22. This observation is likely related to the immunosuppressive effects of androgens in males. The data presented concur with more pronounced immunological alertness demonstrable in females, which may relate to the sex-specific course of some immunological disorders.

Air Pollution and the Airways: Lessons from a Century of Human Urbanization

Since the industrial revolution, air pollution has become a major problem causing several health problems involving the airways as well as the cardiovascular, reproductive, or neurological system. According to the WHO, about 3.6 million deaths every year are related to inhalation of polluted air, specifically due to pulmonary diseases. Polluted air first encounters the airways, which are a major human defense mechanism to reduce the risk of this aggressor. Air pollution consists of a mixture of potentially harmful compounds such as particulate matter, ozone, carbon monoxide, volatile organic compounds, and heavy metals, each having its own effects on the human body. In the last decades, a lot of research investigating the underlying risks and effects of air pollution and/or its specific compounds on the airways, has been performed, involving both in vivo and in vitro experiments. The goal of this review is to give an overview of the recent data on the effects of air pollution on healthy and diseased airways or models of airway disease, such as asthma or chronic obstructive pulmonary disease. Therefore, we focused on studies involving pollution and airway symptoms and/or damage both in mice and humans.

The changes of clinical and histological characteristics of chronic rhinosinusitis in 18 years: Was there an inflammatory pattern shift in southern China?

Background

Nowadays, the heterogeneity of chronic rhinosinusitis (CRS) has attracted extensive attention. The histological patterns and clinical characteristics may vary greatly in different areas and among different groups of people. Prior studies found a shift from the neutrophilic inflammatory pattern to the eosinophilic inflammatory pattern in Asian cities. This study set out with the aim of investigating the changes that have occurred in the past 18 years of southern China and exploring the causes.

Methods

Tissues, clinical, and demographic characteristics were obtained from 473 patients (91 in 2000–2001, 170 in 2010–2011, 212 in 2017–2018) who satisfied the criteria of diffuse (bilateral) chronic rhinosinusitis. The clinical characteristics, including the previous history of allergic rhinitis and asthma, and the major symptoms of rhinosinusitis, were collected. Formalin-fixed nasal tissue was obtained from each patient for calculating inflammatory cells. We also performed immunohistochemistry to evaluate the expression levels of eosinophilic cationic protein (ECP), IgE, myeloperoxidase (MPO), and other Type 1, Type 2, and Type 3 related inflammatory cytokines.

Results

The comorbidity of asthma and atopic disease was higher in 2017–2018 compared to 2000–2001. The histological characteristics revealed a significant increase in tissue eosinophils and decrease in neutrophils in 2017–2018 as compared with 2000–2001. Meanwhile, the proportion of eosinophilic CRS (eCRS) increased significantly from 2000 to 2001 to 2017–2018 (P = 0.03). The tissue eosinophil increase was higher in overweight patients (Body Mass Index, BMI≥24) as compared with non-overweight. There was an increasing trend of ECP, IL-13 and IL-17. Besides, IFN-γ and TNF-α decreased.

Conclusions

There was an eosinophilic shift of diffuse rhinosinusitis inflammatory pattern in southern China over the last 18 years. The proportion of eCRS and difficult-to-treat rhinosinusitis has steadily increased, which is associated with the increase of Type 2, Type 3 cytokines and the decrease of Type 1 cytokines. This study also provided firstly evidence of a strong relationship between overweight and eosinophil shift in the southern Chinese population.

Association of Cotinine-Verified Cigarette Exposure with Chronic Rhinosinusitis in Korean Adults

Chronic rhinosinusitis is known to be influenced by cigarette exposure; however, this relationship is based on the presence of nasal polyps, and objective measurements of cigarette exposure in chronic rhinosinusitis are not well established. This study aimed to estimate the association between chronic rhinosinusitis and smoking status based on self-reported questionnaires and urinary cotinine levels according to the presence of nasal polyps. We analyzed a total of 23,621 participants who participated from the fifth Korea National Health and Nutrition Examination Survey (2010–2012). Serum total and specific IgE level were measured. Higher prevalence of chronic rhinosinusitis with nasal polyps was associated with current smoking status (OR = 1.43, 95% CI = 1.00–2.03). This association was prevalent in participants aged ≤ 50 years (OR = 1.76, 95% CI = 1.01–3.05), and higher urinary cotinine level showed correlation with higher prevalence of chronic rhinosinusitis with nasal polyps in this age group (OR = 1.04, 95% CI = 1.00–1.08). In addition, positive correlation between serum total IgE and urinary cotinine levels was greater in patients with chronic rhinosinusitis (β = 0.493, 95% CI = 0.071–0.916) than in controls (β = 0.062, 95% CI = 0.021–0.103). Aggressive smoking interventions should be performed in patients with chronic rhinosinusitis with nasal polyp, especially in cases of young adults or high serum IgE levels.

Regulation of Human Innate Lymphoid Cells in the Context of Mucosal Inflammation

Since their identification as a unique cell population, innate lymphoid cells (ILCs) have revolutionized our understanding of immune responses, leaving their impact on multiple inflammatory and fibrotic pathologies without doubt. Thus, a tightly controlled regulation of local ILC numbers and their activity is of crucial importance. Even though this has been extensively studied in murine ILCs in the last few years, our knowledge of human ILCs is still lagging behind. Our review article will therefore summarize recent insights into the function of human ILCs and will particularly focus on their regulation under inflammatory conditions. The quality and intensity of ILC involvement into local immune responses at mucosal sites of the human body can potentially be modulated via three different axes: (1) activation of tissue-resident mature ILCs, (2) plasticity and local transdifferentiation of specific ILC subsets, and (3) tissue migration and accumulation of peripheral ILCs. Despite a still ongoing scientific effort in this field, already existing data on the fate of human ILCs under different pathologic conditions clearly indicate that all three of these mechanisms are of relevance for the clinical course of chronic inflammatory and autoimmune diseases and might likewise provide new target structures for future therapeutic strategies.

Increased nasal matrix metalloproteinase-1 and -9 expression in smokers with chronic rhinosinusitis and asthma

A potential mechanism underlying cigarette smoke-induced airway disease is insufficient tissue repair via altered production of matrix metalloproteinases (MMPs). Osteitis is a signature feature of recalcitrant chronic rhinosinusitis (CRS) and often results in revision surgery. The present study aimed to investigate MMP expression in the nasal tissues of asthmatic patients with CRS and any association with cigarette smoking and osteitis. Thirteen smokers with CRS and asthma, 16 non-smokers with CRS and asthma, and seven non-smoker asthmatic patients without CRS were prospectively recruited. The expression of MMPs and associated immunological factors in surgically-obtained nasal tissues was evaluated via real-time PCR and western blotting. Maximal bone thickness of the anterior ethmoid (AE) partition was measured in axial sinus computed tomography (CT) sections. MMP-1 and MMP-9 expression was increased in the nasal tissues of smokers with asthma and CRS via real-time PCR and western blot. Maximal AE partition bone thickness was greater in smokers with CRS and asthma than in non-smokers with CRS and asthma. MMP-1 and MMP-9 levels were correlated with maximal AE bone thickness. Cigarette smoking was associated with the up-regulation of MMP-1 and MMP-9 in the nasal tissues of patients with airway inflammatory diseases, and with AE osteitis, and with therapeutic resistence.