Positive association between chlorinated paraffins and the risk of allergic diseases in children and adolescents.

Contaminants may induce immune response polarization, leading to immune diseases, such as allergic diseases. Evidence concerning the effects of chlorinated paraffins (CPs), an emerging persistent organic pollutant, on immune system is scarce, particularly for epidemiological evidence. This study explores the association between CPs exposure and allergic diseases (allergic rhinitis, atopic eczema, and allergic conjunctivitis) in children and adolescents in the Pearl River Delta (PRD) in China. Herein, 131,304 children and adolescents from primary and secondary schools in the PRD were included and completed the questionnaire survey. The particulate matter (PM) samples were collected in the PRD and the PM2.5-bound CP concentrations were analyzed. In the multivarious adjustment mixed effect model (MEM), an IQR increase in ∑CPs was significantly associated with allergic diseases (rhinitis, eczema, and conjunctivitis) with the estimated odds ratios (ORs) for 1.11 (95% CI: 1.10, 1.13), 1.17 (95% CI: 1.15, 1.19), and 1.82 (95% CI: 1.76, 1.88), respectively. Interaction analysis indicated that overweight and obese individuals might have greater risk. Similar effect estimates were observed in several sensitivity analyses. This study provided epidemiological evidence on the immunotoxicity of CPs. More studies to confirm our findings and investigate mechanisms are needed.

Hydrangea serrata extract attenuates PM-exacerbated airway inflammation in the CARAS model by modulating the IL-33/ST2/NF-κB signaling pathway.

Particulate matter (PM) significantly contributes to the global health crisis of respiratory diseases. It is known to induce and exacerbate conditions such as asthma and respiratory infections. Long exposure to PM can increase the risk of combined allergic rhinitis and asthma syndrome (CARAS). Although therapeutic drugs can be used to improve symptoms of respiratory diseases caused by PM, their usage is often accompanied by side effects. Therefore, many studies are being conducted to discover functional food materials that can more effectively treat respiratory diseases while minimizing the side effects of these therapeutic drugs. This study was conducted to investigate the efficacy of Hydrangea serrata extract (HSE) in airway inflammation in a mouse model of CARAS exacerbated by PM. In the CARAS mouse model worsened by PM, the airway inflammation improvement effect of HSE was evaluated by analyzing allergic nasal symptoms, changes in inflammatory cells, OVA-specific immunoglobulin (Ig) levels, cytokines, mast cell activation, and histopathological findings of both nasal mucosa and lung tissue. HSE effectively reduced OVA-specific IgE and IgG1 and inhibited the production of T helper type 2 (Th2)-related cytokines such as IL-4 and IL-5. Importantly, HSE reduced IL-33 and ST2 expression and inhibited the activation of the NF-κB signaling pathway. In addition, HSE inhibited airway hypersensitivity, mucus production, and inflammatory cell infiltration. These results suggest that HSE may inhibit airway inflammation in CARAS/PM mice by regulating the IL-33/ST2/NF-κB signaling pathway, opening avenues for considering HSE as a potential material for treating allergic airway inflammation diseases in the future.

The Associations of Prenatal Exposure to Fine Particulate Matter and Its Chemical Components with Allergic Rhinitis in Children and the Modification Effect of Polyunsaturated Fatty Acids: A Birth Cohort Study.

BACKGROUND: Polyunsaturated fatty acids (PUFAs) have been shown to protect against fine particulate matter <2.5µm in aerodynamic diameter (PM2.5)-induced hazards. However, limited evidence is available for respiratory health, particularly in pregnant women and their offspring. OBJECTIVES: We aimed to investigate the association of prenatal exposure to PM2.5 and its chemical components with allergic rhinitis (AR) in children and explore effect modification by maternal erythrocyte PUFAs. METHODS: This prospective birth cohort study involved 657 mother-child pairs from Guangzhou, China. Prenatal exposure to residential PM2.5 mass and its components [black carbon (BC), organic matter (OM), sulfate (SO42-), nitrate (NO3-), and ammonium (NH4+)] were estimated by an established spatiotemporal model. Maternal erythrocyte PUFAs during pregnancy were measured using gas chromatography. The diagnosis of AR and report of AR symptoms in children were assessed up to 2 years of age. We used Cox regression with the quantile-based g-computation approach to assess the individual and joint effects of PM2.5 components and examine the modification effects of maternal PUFA levels. RESULTS: Approximately 5.33% and 8.07% of children had AR and related symptoms, respectively. The average concentration of prenatal PM2.5 was 35.50±5.31 µg/m3. PM2.5 was positively associated with the risk of developing AR [hazard ratio (HR)=1.85; 95% confidence interval (CI): 1.16, 2.96 per 5 µg/m3] and its symptoms (HR=1.79; 95% CI: 1.22, 2.62 per 5 µg/m3) after adjustment for confounders. Similar associations were observed between individual PM2.5 components and AR outcomes. Each quintile change in a mixture of components was associated with an adjusted HR of 3.73 (95% CI: 1.80, 7.73) and 2.69 (95% CI: 1.55, 4.67) for AR and AR symptoms, with BC accounting for the largest contribution. Higher levels of n-3 docosapentaenoic acid and lower levels of n-6 linoleic acid showed alleviating effects on AR symptoms risk associated with exposure to PM2.5 and its components. CONCLUSION: Prenatal exposure to PM2.5 and its chemical components, particularly BC, was associated with AR/symptoms in early childhood. We highlight that PUFA biomarkers could modify the adverse effects of PM2.5 on respiratory allergy. https://doi.org/10.1289/EHP13524.

Downregulation of lncRNA CDKN2B-AS1 attenuates inflammatory response in mice with allergic rhinitis by regulating miR-98-5p/SOCS1 axis.

Long non-coding RNA cyclin-dependent kinase inhibitor 2B antisense RNA 1 (CDKN2B-AS1) in various diseases has been verified. However, the underlying mechanism of CDKN2B-AS1 contributes to the development of allergic rhinitis (AR) remains unknown. To evaluate the impact of CDKN2B-AS1 on AR, BALB/c mice were sensitized by intraperitoneal injection of normal saline containing ovalbumin (OVA) and calmogastrin to establish an AR model. Nasal rubbing and sneezing were documented after the final OVA treatment. The concentrations of IgE, IgG1, and inflammatory elements were quantified using ELISA. Hematoxylin and eosin (H&E) staining and immunofluorescence were used to assess histopathological variations and tryptase expression, respectively. StarBase, TargetScan and luciferase reporter assays were applied to predict and confirm the interactions among CDKN2B-AS1, miR-98-5p, and SOCS1. CDKN2B-AS1, miR-98-5p, and SOCS1 levels were assessed by quantitative real-time PCR (qRT-PCR) or western blotting. Our results revealed that CDKN2B-AS1 was obviously over-expressed in the nasal mucosa of AR patients and AR mice. Down-regulation of CDKN2B-AS1 significantly decreased nasal rubbing and sneezing frequencies, IgE and IgG1 concentrations, and cytokine levels. Furthermore, down-regulation of CDKN2B-AS1 also relieved the pathological changes in the nasal mucosa, and the infiltration of eosinophils and mast cells. Importantly, these results were reversed by the miR-98-5p inhibitor, whereas miR-98-5p directly targeted CDKN2B-AS1, and miR-98-5p negatively regulated SOCS1 level. Our findings demonstrate that down-regulation of CDKN2B-AS1 improves allergic inflammation and symptoms in a murine model of AR through the miR-98-5p/SOCS1 axis, which provides new insights into the latent functions of CDKN2B-AS1 in AR treatment.

Fructus Xanthii and Magnolia liliiflora Volatile Oils Liposomes-Loaded Thermosensitive in situ Gel for Allergic Rhinitis Management.

Purpose: The aim of the present study was to fabricate a Fructus Xanthii and Magnolia liliiflora volatile oils liposomes-loaded thermosensitive in situ gel (gel/LIP/volatile oil) for effectively treating allergic rhinitis via intranasal administration. Patients and Methods: Particle size, polymer dispersity index (PDI), entrapment effectiveness, and cumulative drug permeation of the developed liposomes were assessed. Then, a thermoreversible in situ gel was created using the liposomes loaded with volatile oils of Fructus Xanthii and Magnolia liliiflora. The effectiveness of this treatment for allergic rhinitis was confirmed by evaluating nasal symptoms, and hematological results, after injecting the formulation into the ovalbumin (OVA)-sensitized mice, we conducted hematoxylin-eosin staining (HE) and immunohistochemistry to evaluate the outcomes. The effects of the gel/LIP/volatile oil formulation for nasal delivery of volatile oil in the treatment of rhinitis were then assessed. Results: The average particle size was 95.1 ± 3.6 nm, and the encapsulation efficiencies of Fructus Xanthii and Magnolia liliiflora volatile oils were 70.42 ± 5.41% and 67.10 ± 6.08%, respectively. Drug loadings of Fructus Xanthii and Magnolia liliiflora volatile oils were 9.10 ± 0.98% and 16.10 ± 1.03%, respectively. The binary formulation produced a gel rapidly in the nasal cavity with a strong mucosal adherence at a temperature of delivering volatile oil to the nasal mucosa steadily and continuously. After nasal administration, the gel/LIP/volatile oil sustained the volatile oil delivery into the mucosa. In comparison to the monolithic formulations, the gel/LIP/volatile oil binary formulation exhibited superior performance in terms of drug delivery capability and pharmacodynamic effects. Conclusion: This binary preparation displayed the ability to deliver drugs to the nasal mucosa and exhibited positive pharmacodynamic effects in treating OVA-induced rhinitis in mice. As a result, it has the potential to serve as a delivery platform for Traditional Chinese medicine in the treatment of allergic rhinitis.

Intrauterine and early postnatal exposures to submicron particulate matter and childhood allergic rhinitis: A multicity cross-sectional study in China.

BACKGROUND: Airborne particulate matter pollution has been linked to occurrence of childhood allergic rhinitis (AR). However, the relationships between exposure to particulate matter with an aerodynamic diameter ≤1 µm (PM1) during early life (in utero and first year of life) and the onset of childhood AR remain largely unknown. This study aims to investigate potential associations of in utero and first-year exposures to size-segregated PMs, including PM1, PM1-2.5, PM2.5, PM2.5-10, and PM10, with childhood AR. METHODS: We investigated 29286 preschool children aged 3-6 years in 7 Chinese major cities during 2019-2020 as the Phase II of the China Children, Families, Health Study. Machine learning-based space-time models were utilized to estimate early-life residential exposure to PM1, PM2.5, and PM10 at 1 × 1-km resolutions. The concentrations of PM1-2.5 and PM2.5-10 were calculated by subtracting PM1 from PM2.5 and PM2.5 from PM10, respectively. Multiple mixed-effects logistic models were used to assess the odds ratios (ORs) and 95% confidence intervals (CIs) of childhood AR associated with per 10-µg/m3 increase in exposure to particulate air pollution during in utero period and the first year of life. RESULTS: Among the 29286 children surveyed (mean ± standard deviation, 4.9 ± 0.9 years), 3652 (12.5%) were reported to be diagnosed with AR. Average PM1 concentrations during in utero period and the first year since birth were 36.3 ± 8.6 µg/m3 and 33.1 ± 6.9 µg/m3, respectively. Exposure to PM1 and PM2.5 during pregnancy and the first year of life was associated with an increased risk of AR in children, and the OR estimates were higher for each 10-µg/m3 increase in PM1 than for PM2.5 (e.g., 1.132 [95% CI: 1.022-1.254] vs. 1.079 [95% CI: 1.014-1.149] in pregnancy; 1.151 [95% CI: 1.014-1.306] vs. 1.095 [95% CI: 1.008-1.189] in the first year of life). No associations were observed between AR and both pre- and post-natal exposure to PM1-2.5, indicating that PM1 rather than PM1-2.5 contributed to the association between PM2.5 and childhood AR. In trimester-stratified analysis, childhood AR was only found to be associated with exposure to PM1 (OR = 1.077, 95% CI: 1.027-1.128), PM2.5 (OR = 1.048, 95% CI: 1.018-1.078), and PM10 (OR = 1.032, 95% CI: 1.007-1.058) during the third trimester of pregnancy. Subgroup analysis suggested stronger PM-AR associations among younger (<5 years old) and winter-born children. CONCLUSIONS: Prenatal and postnatal exposures to ambient PM1 and PM2.5 were associated with an increased risk of childhood AR, and PM2.5-related hazards could be predominantly attributed to PM1. These findings highlighted public health significance of formulating air quality guideline for ambient PM1 in mitigating children's AR burden caused by particulate air pollution.

Association between environmental mercury exposure and allergic disorders in Korean children: Korean National Environmental Health Survey (KoNEHS) cycles 3-4 (2015-2020).

Although previous studies have suggested potential adverse effects of mercury on a child's immune system, the associations have been inconsistent. We aimed to determine the association between urinary mercury levels and allergic diseases in Korean children with high mercury exposure. Data from 853 and 710 children aged 6-11 years in the Korean National Environmental Health Survey (KoNEHS) cycle 3 (2015-2017) and cycle 4 (2018-2020) were analyzed. We examined the association between mercury exposure and the prevalence of atopic dermatitis (AD), asthma, allergic rhinitis (AR), and allergic multimorbidity. After adjusting for all covariates, the urinary mercury level was positively associated with AD in the 2015-2017 study (OR = 1.34, 95% CI = 1.01, 1.79) and AR in 2018-2020 study (OR = 1.46, 95% CI = 1.01, 2.10). Pooled effects showed OR of 1.34 (95% CI = 1.01, 1.79) for AD and 1.47 (95% CI = 1.01, 2.12) for allergic multimorbidity. The association with allergic multimorbidity was greater in boys (OR = 1.88, 95% CI = 1.01, 3.49) than in girls (OR = 1.25, 95% CI = 0.73, 2.14). These results suggest that environmental mercury exposure may exacerbate symptoms of atopic dermatitis and allergic multimorbidity in children.

Exposure of nonylphenol promoted NLRP3 inflammasome and GSDMD-mediated pyroptosis in allergic rhinitis mice.

Studies have confirmed that the intake of nonylphenol (NP) can increase nasal symptoms, eosinophils, and Th2 responses in allergic rhinitis (AR) mice. However, the molecular mechanism of NP exacerbating AR inflammatory response remains unclear. Recent data suggest that NOD-like receptor 3 (NLRP3) inflammasome-mediated pyroptosis contributes to AR development. To investigate the effects of NP on NLRP3 inflammasomes and pyroptosis, an AR mouse model induced by ovalbumin (OVA) was established and treated with 0.5 mg/kg/d NP every other day. Nasal symptoms were evaluated after the final OVA instillation. Mast cells and Eosinophils in the nasal mucosa were observed using toluidine blue and Sirius red staining, respectively. The levels of NLRP3, Caspase-1, ASC, phospho-nuclear factor kappa B (NF-κB) p65, interleukin (IL)-6, TNF-α, IL-18, GSDMD and IL-1ß, were assessed by using immunohistochemical staining, ELISA, quantitative real-time PCR, or Western blot. Exposure to NP aggravates AR symptoms and promotes eosinophils, mast cells, and inflammatory factors release, along with significantly increased of NF-κB, NLRP3, Caspase-1, ASC, and GSDMD. It was concluded that NP exposure promotes NLRP3 inflammasome and GSDMD-mediated pyroptosis of the nasal mucosa. Targeted of NLRP3 and GSDMD-mediated pyroptosis may be a novel therapeutic strategy for AR exposed to NP.

A Real-World Observational Study to Evaluate the Safety and Effectiveness of Fluticasone Furoate-Oxymetazoline Fixed Dose Combination Nasal Spray in Patients with Allergic Rhinitis.

BACKGROUND: Allergic rhinitis (AR) has shown an increasing prevalence leading to a considerable medical and social burden. Nasal congestion is the cardinal symptom of AR, and the upper respiratory tract is most affected by this long-lasting ailment. Intranasal corticosteroids alleviate nasal congestion, along with other symptoms of AR, but their effect is not evident immediately. Oxymetazoline has a rapid onset of action, but its use should be limited to 3-5 days. OBJECTIVE: The study aimed to evaluate the safety and effectiveness of the fixed-dose combination nasal spray containing fluticasone furoate and oxymetazoline hydrochloride (FF + OXY) 27.5/50 mcg once daily in patients with AR in a real-world clinical setting. METHODS: The study was a prospective, open-label, single-arm, multicenter, real-world observational study conducted in patients with AR for a period of 28 days. Patients (n = 388) with a diagnosis of AR were treated with a combination of FF + OXY nasal spray. Total nasal symptom score (TNSS), total ocular symptom score (TOSS) and total symptom score (TSS) were documented at baseline and at the end of study period. The overall effectiveness of treatment with FF + OXY was rated by the investigators as very good/good/satisfactory/poor (4-point Likert scale) for each patient. RESULTS: Treatment with FF + OXY resulted in significant reduction in the TNSS, TOSS and TSS, from 7.18 ± 3.38 at baseline to 0.20 ± 0.84 (p < 0.001), from 2.34 ± 2.29 at baseline to 0.09 ± 0.53 (p < 0.001), from 9.51 ± 4.94 at baseline to 0.29 ± 1.32 (p < 0.001) at 28 days respectively. With respect to effectiveness, the investigators reported very good effectiveness in 52.12% of patients. No serious adverse events were reported. CONCLUSION: The fixed-dose combination of once-daily fluticasone furoate and oxymetazoline hydrochloride nasal spray 27.5/50 mcg was effective in relieving the nasal congestion and reduction of TNSS, TOSS and TSS in patients suffering from AR. The combination was safe and well tolerated with no rebound congestion throughout the treatment period.

Biologics in allergic rhinitis.

This paper aims to review biologics in allergic rhinitis (AR). Biologic agents of Omalizumab, Dupilumab, Mepolizumab, Reslizumab, and Benralizumab are reviewed in detail. The search is performed in "Pubmed," "Google," Google Scholar" and EBSCO Academic Search Ultimate (EKUAL) database of Kirikkale University Library from 2021 to 2000, and randomized and/or placebo-controlled studies, review papers, meta-analysis, and reports are taken into consideration. The search was performed with the keywords of "allergic rhinitis," "biologics," "biologic agents," "Omalizumab," "Dupilumab," "Mepolizumab," "Reslizumab," "Benralizumab," "Anti IgE," "Anti-IL-4/IL-13", "Anti IL-5". Search is also performed in the "U.S. Food and Drug Administration" (FDA) and "European Medicines Agency" (EMA) web systems. Biological agents such as monoclonal antibodies (MAb) in treatment are called biological therapy or biotherapy. Omalizumab is a humanized Anti-IgE monoclonal antibody. Omalizumab treatment improved the Daily Nasal Rescue Medication Score (DNSSS) and decreased the use of antiallergic drugs in seasonal and perennial AR and rhino-conjunctivitis. Omalizumab is also used in specific immunotherapy patients with allergic rhinitis and reduced allergic reactions associated with allergen immunotherapy, such as anaphylaxis. Dupilumab is an Anti-IL-4/IL-13 biologic agent. Dupilumab treatment significantly improved sino-nasal Outcome Test (SNOT-22) total scores in perennial allergic rhinitis. Anti-IL-5 monoclonal antibodies of Mepolizumab, Reslizumab Benralizumab reduce the number of eosinophils in the blood and tissue, corticosteroid addiction and asthma attacks are reduced, and their use in the treatment of severe eosinophilic asthma has been approved. Biologics, especially Omalizumab, and Dupilumab, may be used more in allergic rhinitis.

Associations between long-term exposure to PM2.5 chemical constituents and allergic diseases: evidence from a large cohort study in China.

BACKGROUND: Exposure to air pollutants may cause immune responses and further allergic diseases, but existing studies have mostly, if not all, focused on effects of short-term exposure to PM2.5 on allergic diseases. OBJECTIVES: We estimated associations of long-term exposure to PM2.5 chemical constituents with allergic disease risks and effect modification. METHODS: We used the baseline of a newly established, provincially representative cohort of 51,480 participants in southwest China. The presence of allergic rhinitis, allergic asthma, urticaria, and allergic conjunctivitis was self-reported by following a formed questionnaire in face-to-face interviews. The average concentrations of PM2.5 chemical constituents (NO3-, SO42-, NH4+, organic matter [OM], and black carbon [BC]) over participants' residence were estimated using machine learning models. Logistic regression with double robust estimator and weighted quantile sum regression were used to estimate the effects of PM2.5 chemical constituents on allergic disease risks, as well as relative importance of each PM2.5 chemical constituent. RESULTS: Per interquartile range increase in the concentration of all PM2.5 chemical constituents was associated with the elevated risks for allergic asthma (OR = 1.79 [1.41-2.26]), allergic conjunctivitis (1.54 [1.19-2.00]), urticaria (1.36 [1.25-1.48]), and allergic rhinitis (1.18 [1.11-1.26]). NO3- contributed more to risks for allergic asthma (weight = 46.05 %), urticaria (72.29 %), and allergic conjunctivitis (47.65 %), while NH4+ contributed more to allergic rhinitis (78.07 %). OM contributed most to the risks for allergic asthma (30.81 %) and allergic conjunctivitis (31.40 %). BC was also associated with allergic rhinitis, urticaria, and allergic conjunctivitis, only with a considerable weight for urticaria (24.59 %). Joint effects of PM2.5 chemical constituents on risks for allergic rhinitis and urticaria were stronger in minorities and farmers than their counterparts. CONCLUSION: Long-term exposure to PM2.5 chemical constituents was associated with the increased allergic disease risks, with NO3- and NH4+ accounting for the largest variance of the associations. Our findings would serve as scientific evidence for developing more explicit strategies of air pollution control.

Xiao-qing-long-tang ameliorates OVA-induced allergic rhinitis by inhibiting ILC2s through the IL-33/ST2 and JAK/STAT pathways.

BACKGROUND: Allergic rhinitis (AR) is a chronic inflammatory disease of the nasal mucosa that is mediated by immunoglobulin E (IgE). Xiao-qing-long-tang (XQLT) is a traditional Chinese medicine compound that is widely used to treat respiratory diseases such as AR. However, the underlying mechanism of the effect of XQLT on AR remains unclear. PURPOSE: To elucidate the effect of XQLT on ovalbumin (OVA)-induced AR and the mechanisms of action. METHODS: The therapeutic efficacy of XQLT was evaluated in a well-established OVA-induced AR mouse model. Nasal symptoms were analyzed, type 2 cytokines and OVA-sIgE levels were measured, nasal mucosa tissues were collected for histological analysis, and the changes of Group 2 innate lymphoid cells (ILC2s) and the IL-33/ST2 and JAK/STAT signaling pathways in the nasal mucosa were observed. RESULTS: XQLT significantly alleviated the nasal symptoms and histological damage to the nasal mucosa in AR mice, and reduced the levels of type 2 cytokines and OVA-sIgE. In addition, after XQLT treatment, the numbers of ILC2s in the nasal mucosa of AR mice were reduced, and the mRNA levels of the transcription factors GATA3 and ROR-α were decreased. Moreover, IL-33/ST2 signaling pathway was inhibited. The costimulatory cytokine associated JAK/STAT signaling pathway was also inhibited in ILC2s. CONCLUSION: Our study demonstrated that XQLT regulated ILC2s through the IL-33/ST2 and JAK/STAT pathways to ameliorate type 2 inflammation in OVA-induced AR. These findings suggest that XQLT might be used to treat AR.

Cineole inhibits the biosynthesis of leukotrienes and prostaglandins to alleviate allergic rhinitis: Insights from metabolomics.

Allergic rhinitis (AR) is a common allergic disease characterized by nasal congestion, rhinorrhoea, and sneezing. Cineole, a monoterpenoid compound widely present in various volatile oils, has a wide range of pharmacological activities and is of interest in allergic airway diseases for its anti-inflammatory and anti-mucus production abilities. However, the protective effects of cineole in mice with allergic rhinitis and its mechanisms have not been well investigated. In this study, the protective effect of cineole against ovalbumin-induced (OVA-induced) allergic rhinitis and its molecular mechanism is investigated by metabolomic analysis based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). OVA combined with aluminum hydroxide adjuvant is used to sensitize and establish the allergic rhinitis (AR) mouse model. The mice are randomly divided into groups of control, AR, cineole (30 mg/kg), and budesonide (38.83 µg/kg). The pharmacodynamic results show that cineole significantly reduces the levels of Th2-type cytokines and OVA-specific IgE (OVA-sIgE) in AR mice, improves nasal mucosal tissue damage and alleviates nasal symptoms compared to the untreated AR group. Metabolomic results show that arachidonic acid (AA) metabolism and tryptophan (Trp) metabolism are reprogrammed on the basis of 27 significantly altered metabolites. Further studies show that cineole inhibits the biosynthesis of pro-inflammatory lipid mediators leukotrienes (LTs) and prostaglandins (PGs) in mice by inhibiting the activity of 5-lipoxygenase (5-LOX) and cyclooxygenase-2 (COX-2) in the arachidonic acid metabolic (AA metabolic) pathway. It also inhibits the production of Th2 cytokines and inflammatory cell infiltration, thereby alleviating symptoms such as nasal congestion and nasal leakage. These results reveal the action and molecular mechanism of cineole in alleviating AR and provide a theoretical basis for the clinical application of cineole in treating AR.

The ratio of total IgE level at week 16 to baseline significantly correlated with the clinical response to omalizumab in moderate to severe allergic rhinitis patients.

OBJECTIVE: To analyze whether the ratio of total IgE level at week 16 to baseline could be used as an indicator to evaluate clinical efficacy of patients treated with omalizumab. METHODS: We retrospectively analyzed the clinical characteristics of 62 patients with moderate-to-severe allergic rhinitis treated with omalizumab, and compared the pre-and post-treatment nasal visual analog scale (n-VAS) scores, the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), Rhinitis Control Assessment Test (RCAT), improvement in nasal congestion, number of acute episodes of rhinitis, and total IgE levels in serum. The relationship between the efficacy of treatment with omalizumab and the change in total IgE levels before and after treatment was further analyzed. RESULTS: This study included 62 patients with moderate-to-severe allergic rhinitis, of which 48 demonstrated significant improvement after 16 weeks of omalizumab therapy; the results of 16 weeks' omalizumab treatment in 14 patients did not show significant improvements in allergic rhinitis symptoms based on RACT scores. After 16 weeks of omalizumab treatment, the RQLQ score decreased from (36.6 ± 13.7) at baseline level to (9.1 ± 12.6) after 16 weeks treatment.The ratio of total IgE at week 16 to total IgE levels at baseline was (2.9 ± 1.4) KU/L in 62 patients. And the ratio of total IgE levels at week 16 to total IgE levels at baseline was (3.3 ± 1.4) KU/L for responders and (1.6 ± 0.5) KU/L for non-responders. CONCLUSION: The ratio of total IgE level at week 16 to baseline significantly correlated with the clinical response to omalizumab in moderate to severe allergic rhinitis patients, when the ratio of total IgE level at week 16 to baseline was ≥2.0. Omalizumab effectively treated patients with moderate-to-severe allergic rhinitis, and improved their quality of life.

Bergapten ameliorates combined allergic rhinitis and asthma syndrome after PM2.5 exposure by balancing Treg/Th17 expression and suppressing STAT3 and MAPK activation in a mouse model.

Combined allergic rhinitis and asthma syndrome (CARAS) causes chronic respiratory inflammation in allergic individuals. Long-term exposure to particulate matter 2.5 (PM2.5; particles 2.5 µm or less in diameter) can aggravate respiratory damage. Bergapten (5-methoxysporalen) is a furocoumarin mostly found in bergamot essential oil and has significant antioxidant, anticancer, and anti-inflammatory activity. This study created a model in which CARAS was exacerbated by PM2.5 exposure, in BALB/c mice and explored the potential of bergapten as a therapeutic agent. The bergapten medication increased ovalbumin (OVA)-specific immunoglobulin (Ig) G2a level in serum and decreased OVA-specific IgE and IgG1 expression. Clinical nasal symptoms diminished significantly, with weakened inflammatory reaction in both the nasal mucosa and lungs. Furthermore, bergapten controlled the T helper (Th)1 to Th2 ratio by increasing cytokines associated with Th1-like interleukin (IL)-12 and interferon gamma and decreasing the Th2 cytokines IL-4, IL-5, and IL-13. Factors closely related to the balance between regulatory T cells and Th17 (such as IL-10, IL-17, Forkhead box protein P3, and retinoic-related orphan receptor gamma) were also regulated. Notably, pro-inflammatory cytokines IL-6, IL-1ß, and tumor necrosis factor-alpha were reduced by bergapten, which suppressed the activation of both the signal transducer and activator of transcription 3 signaling pathway and the mitogen-activated protein kinase signaling pathway. Therefore, bergapten might have potential as a therapeutic agent for CARAS.

Hydroxysafflor yellow A attenuates allergic response of ovalbumin induced allergic rhinitis via Nrf2/HO-1 and inflammatory signaling pathways.

Allergic reaction is the most common nasal conditions worldwide and it will remain throughout life. The symptoms of an allergic reaction include sneezing, itching, hives, swelling, difficulty breathing, and a runny nose. Hydroxysafflor yellow A (HYA) is a flavonoid compound which is the active phyto-constituent of flower of Carthamus tinctorius L., and exhibited the various medicinal activities like antioxidant, anti-inflammatory and cardiovascular protective effects. This study aimed to assess the efficacy and mode of action of HYA against the allergic rhinitis induced by ovalbumin in mice. HYA was given orally to the Swiss BALB/s mice once daily, 1 h before, they were challenged with ovalbumin (OVA) via intranasal administration, after that the mice were sensitized via intraperitoneal injection of OVA. Allergic nasal symptoms, body weight, spleen weight, OVA-specific immunoglobulins, inflammatory cytokines, Th17 cytokines and Th17 transcription factors also estimated. HYA had a significant (p < .001) effect on body weight and reduced spleen weight. It effectively decreased the nasal symptoms of allergy such as sneezing, rubbing, and redness. HYA significantly reduced the level of malonaldehyde (MDA) and improved levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and glutathione (GSH). It also remarkably decreased the levels of Th2 cytokines and Th17 transcription factors like RAR-related orphan receptor gamma (ROR-γ), signal transducer and activator of transcription 3 (STAT3) and phosphor signal transducer and activator of transcription 3 (p-STAT3), while increasing levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). The treatment with HYA improved the lung histology in mice with allergic rhinitis. The results suggest that HYA may have therapeutic potential against ovalbumin-induced allergic rhinitis in mice, by altering the Th17/Treg balance and improving the Nrf2/HO-1 signaling pathway.

The Role of Substance P Receptor Antagonists in Allergic Rhinitis: Ovalbumin-Induced Rat Model.

OBJECTIVE: Substance P is a peptide from the tachykinin family, which is found in peripheral and central nervous systems, causing vasodilation and increased secretion in the nasal mucosa. In this study, we aimed to investigate whether the experimental model of allergic rhinitis will cause allergic changes in the larynx and to compare the effects of aprepitant, a substance P antagonist, on nasal symptoms in allergic rhinitis, and histopathological changes in the nasal and laryngeal mucosa with antihistamine and leukotriene receptor antagonists (LTRA). STUDY DESIGN: An experimental animal study. METHOD: The study was carried out on 34 healthy 8-12 weeks old female Sprague Dawley rats in 5 groups. The rats in which an experimental allergic rhinitis model was created with ovalbumin were scored by observing their nasal symptoms, and nasal and laryngeal mucous membranes included in the study were evaluated histopathologically after medications. RESULTS: As a result of the analysis of the data obtained from the study, antihistamine and LTRA significantly reduced the symptoms of nose scratching and sneezing, while aprepitant did not affect nasal symptoms. In the histopathological examination of the larynx, effects that would make a significant difference were found in the allergy group when compared to the control group. On the larynx, aprepitant reduced pseudostratification significantly compared to the allergy group. CONCLUSION: Aprepitant provides histopathological changes in the treatment of allergic rhinitis, but does not have sufficient effect on nasal symptoms. The effect of aprepitant on the larynx has not been clearly demonstrated. LEVEL OF EVIDENCE: NA Laryngoscope, 133:2891-2897, 2023.

Involvements of Nrf2 and oxidative stress in the ozone-elicited exacerbation in an allergic rhinitis model.

OBJECTIVE AND DESIGN: An experimental rat allergic rhinitis(AR) model was made to explore the effect of different concentrations of ozone exposure and evaluate the roles of nuclear factor erythroid 2-related factor 2(Nrf2) and oxidative stress in ozone exposure. METHOD: Sprague-Dawley rats were sensitized with ovalbumin (OVA). Three groups of AR rats were exposed respectively to different concentrations of ozone for 2 h on 6 weeks. Nasal symptoms and OVA- specific Ig E in the serum were evaluated. The pathological changes in the nasal mucosa were examined. Malondialdehyde (MDA) level and activity of superoxide dismutase(SOD) and glutathione peroxidase (GSH-Px,GPX) in the nasal mucosa tissue were measured through a spectrophotometry-based method. Nrf2、Kelch-1ike ECH- associated protein-l (Keap1) proteins was measured by western blotting. GPX1、GPX2 mRNA were detected by quantitative real time-PCR(qRT-PCR). RESULTS: Our results showed that ozone exposure induced a significant increase of the number of sneezes, nasal rubs, amount of nasal secretion and OVA-sIgE in the serum of AR model. Ozone effected oxidative stress in different concentration. The content of MDA in AREH group was significantly higher than AR groups. The activities of SOD and GSH-Px in nasal mucosa showed different trends in different concentration groups. The activities of SOD and GSH-Px in AREL and AREM groups were higher than AR group, but decreased at AREH group. The nucleoprotein level of Nrf2 in AREL and AREM groups was higher than AR groups. However, in AREH group, it was significantly decreased, compared with AREL and AREM groups. GPX1 and GPX2 mRNA levels in nasal mucosa showed the same trend in different exposure groups. CONCLUSIONS: Different concentrations of ozone inhalation causes changes of the expression of Nrf2 nuclear protein and its target genes in nasal mucosa of AR. High concentration ozone breaks the redox balance and aggravates oxidative damage in AR. This study suggests that inhibiting oxidative stress might be a solution for ozone-elicited detrimental effects on AR.

DPP4 Inhibitor Sitagliptin Reduces Inflammatory Responses and Mast Cell Activation in Allergic Rhinitis.

INTRODUCTION: DPP4 is thought to be involved in certain immune processes and plays an important role in allergic reactions in the lungs. The effect of the DPP4 inhibitor sitagliptin on the effector phase of allergic rhinitis (AR) in ovalbumin (OVA)-sensitized mice and on mast cell degranulation in vitro was assessed. METHODS: The AR mouse model was established by intraperitoneal injection combined with OVA intranasal method. OVA was injected intraperitoneally 3 times for the first 2 weeks, and the mice were subsequently given DPP4 inhibitors by oral gavage, accompanied by an OVA intranasal challenge. The impacts of DPP4 inhibitors on DPP4 levels in mouse model were determined. Nasal mucosa tissue was collected for H&E staining and toluidine blue staining. Immunoglobulin E (IgE) levels and histamine levels were analyzed, and IL-4, IL-5, and IL-12 as well as IFN-γ levels were assessed. Following the treatment of dinitrophenol (DNP)-IgE or DNP-IgE plus sitagliptin in RBL-2H3 cells, ß-hexosaminidase activity was analyzed and toluidine blue staining was performed. RESULTS: DPP4 level was reduced in AR patients, as well as in AR mouse models. Nasal allergic symptoms such as sneezing and nose-scratching showed high frequency in OVA-induced mice. Sitagliptin treatment during the intranasal challenge of OVA decreased DPP4 levels, suppressed allergic symptoms, eosinophil infiltration, IgE levels, mast cell infiltration, as well as the levels of inflammatory cytokines. We further found that sitagliptin inhibited mast cell activation and histamine levels in vitro. CONCLUSION: Sitagliptin suppresses the effector phase of AR, and this mechanism is partly attributed to the suppression of inflammatory response and mast cell degranulation.

Apigenin attenuates inflammatory response in allergic rhinitis mice by inhibiting the TLR4/MyD88/NF-κB signaling pathway.

BACKGROUND: Allergic rhinitis (AR) is an immunoglobulin E (IgE)-mediated immune inflammatory response that mainly affects the nasal mucosa. Currently, there is evidence that apigenin, as a flavonoid, has anti-allergic potential. MATERIAL/METHODS: In vitro, compound 48/80 and lipopolysaccharide (LPS) were used to induce mast cell activation and inflammation in HMC-1 cells. In vivo, ovalbumin (OVA) induced and stimulated AR in BALB/c mice. ELISA was used to detect the contents of ß-hexosaminidase, histamine, eosinophil cationic protein (ECP), OVA-specific IgE, IgG1, and IgG2a, inflammatory factors in cells and mouse serum. Cell viability and apoptosis were measured with MTT and flow cytometry. Toll like receptor 4 (TLR4)/myeloid differentiation factor88 (MyD88)/Nuclear transcription factor-κB (NF-κB) pathway-related proteins in cells and mouse nasal mucosa tissues were analyzed with Western blotting. The levels of Th1 (IFN-γ) and Th2 (IL-4, IL-5, and IL-13) cytokines and Th1 (T-bet) and Th2 (GATA-3) specific transcription factors were also assessed. The ratio of Th1 (CD4+ IFN-γ+ ) / Th2 (CD4+ IL-4+ ) cells in mouse peripheral blood mononuclear cells was evaluated by flow cytometry. RESULTS: Apigenin significantly inhibited compound 48/80-induced secretion of ß-hexosaminidase and histamine. Apigenin blocked LPS-induced decrease in cell viability and increase in cell apoptosis and inflammatory cytokine secretion by suppressing the activity of the TLR4/MyD88/NF-κB pathway. Apigenin treatment reduced the levels of OVA-specific IgE, IgG1 and IgG2a as well as ß-hexosaminidase, histamine and ECP levels in mouse serum. Moreover, administration with apigenin decreased Th2 cytokine and transcription factor levels and increased Th1 cytokine and transcription factor levels, and promoted the ratio of Th1/Th2 cells in AR mice. Additionally, apigenin significantly alleviated nasal symptoms and nasal eosinophil infiltration in AR mice. CONCLUSIONS: Apigenin alleviates the inflammatory response of allergic rhinitis by inhibiting the activity of the TLR4/MyD88/NF-κB signaling pathway.