Nasal Lavage Fluid Research Articles

Butyrate inhibits type 2 inflammation in eosinophilic chronic rhinosinusitis

Butyrate and other Short-chain fatty acids (SCFAs) are microbial metabolites from Bacteroides and Clostridium species that may suppress type 2 inflammation. However, the mechanisms of SCFAs in the nasal sinuses are not fully understood. We aimed to clarify the in vitro and in vivo roles of SCFAs in eosinophilic chronic rhinosinusitis (ECRS) pathophysiology. We investigated whether SCFAs induced changes in type 2 cytokines, IgE, and apoptosis and the roles of GPR41, GPR43, and histone deacetylase. Analysis of the control subjects demonstrated that butyrate of SCFAs effectively inhibited type 2 cytokine production in PBMCs, ILC2s, and CD4+ T cells and IgE production in CD19+ B cells. In annexin V analysis, butyrate also induced late apoptosis of PBMCs. The butyrate-induced inhibition of type 2 cytokines appeared involved in histone deacetylase inhibition but not in GPR41 or GPR43. In an analysis of ECRS in humans, butyrate inhibited type 2 cytokine production in PBMCs and nasal polyp-derived cells. The butyrate concentration in nasal lavage fluid was significantly decreased in ECRS patients compared to controls and non-ECRS patients. Our findings confirm that butyrate can inhibit type 2 inflammation and may be a potential therapeutic target for ECRS.

Design and Characterization of a New Formulation for the Delivery of COVID-19-mRNA Vaccine to the Nasal Mucosa.

Chitosan, a natural polysaccharide derived from chitin, possesses biocompatibility, biodegradability, and mucoadhesive characteristics, making it an attractive material for the delivery of mRNA payloads to the nasal mucosa and promoting their uptake by target cells such as epithelial and immune cells (e.g., dendritic cells and macrophages). In this project, we aimed at developing novel lipid-based nanoformulations for mRNA delivery to counteract the pandemic caused by SARS-CoV-2 virus. The formulations achieved a mRNA encapsulation efficiency of ~80.2% with chitosan-lipid nanoparticles, as measured by the RiboGreen assay. Furthermore, the evaluation of SARS-CoV-2 Spike (S) receptor-binding domain (RBD) expression via ELISA for our vaccine formulations showed transfection levels in human embryonic kidney cells (HEK 293), lung carcinoma cells (A549), and dendritic cells (DC 2.4) equal to 9.9 ± 0.1 ng/mL (174.7 ± 1.1 fold change from untreated cells (UT)), 7.0 ± 0.2 ng/mL (128.1 ± 4.9 fold change from UT), and 0.9 ± 0.0 ng/mL (18.0 ± 0.1 fold change from UT), respectively. Our most promising vaccine formulation was also demonstrated to be amenable to lyophilization with minimal degradation of loaded mRNA, paving the way towards a more accessible and stable vaccine. Preliminary in vivo studies in mice were performed to assess the systemic and local immune responses. Nasal bronchoalveolar lavage fluid (BALF) wash showed that utilizing the optimized formulation resulted in local antibody concentrations and did not trigger any systemic antibody response. However, if further improved and developed, it could potentially contribute to the management of COVID-19 through nasopharyngeal immunization strategies.

Yingxiang Acupoint Embedding Improves Mucosal Barrier Function in Rats with Local Allergic Rhinitis

Introduction: Epithelial barrier disruption is the initial cause of various diseases. We previously reported that acupoint catgut embedding (AE) improves tight junction proteins (TJs) in rats with allergic rhinitis. However, whether AE improves the epithelial barrier in local allergic rhinitis (LAR) remains unknown. Methods: A total of 36 Sprague Dawley (SD) male rats aged 5–7 weeks were divided into 6 groups with 6 rats each: control group, LAR model group, false acupoint embedding + LAR group, acupoint embedding + LAR group, capsaicin + LAR group, and tunicamycin + acupoint embedding + LAR group. Behavioral observation, ELISA to detect inflammatory factors in nasal lavage fluid and serum IgE, nasal mucosal permeability test, hematoxylin-eosin staining, PCR to detect Substance P (SP), Western blot, and immunofluorescence to detect endoplasmic reticulum stress (ERS) index and TJs were used to investigate the mechanism of AE in LAR. Results: AE improved the symptoms and pathological features of nasal mucosa of LAR rats, reduced the inflammatory factors (IL4, IL5, IL13) of nasal lavage fluid, and showed no significant change in serum IgE levels in all groups. In addition, AE decreased the expression of SP in nasal mucosa of LAR rats, inhibited ERS, increased the expression of tight junction protein, reduced the permeability of nasal mucosa, and improved the function of nasal mucosal barrier. Conclusion: This study confirms that AE can improve the nasal mucosal barrier function of LAR by reducing the expression of SP, inhibiting ERS and increasing the expression of TJs, thus enhancing the nasal mucosal barrier function.

Murine model of eosinophilic chronic rhinosinusitis with nasal polyposis inducing neuroinflammation and olfactory dysfunction

BackgroundChronic rhinosinusitis (CRS) is a common inflammatory condition affecting the nasal and paranasal sinus mucosa, often accompanied by olfactory dysfunction. Eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) is a subtype of CRS characterized by eosinophilic infiltration. Animal models for ECRSwNP with olfactory dysfunction are necessary for exploring potential therapeutic strategies. ObjectiveThe aim of this study was to establish a mouse model of ECRSwNP combined with olfactory dysfunction in a shorter timeframe using intranasal ovalbumin (OVA) and Aspergillus protease (AP) administration. The efficacy of the model was validated by evaluating sinonasal inflammation, cytokine levels, olfactory function, and neuroinflammation in the olfactory bulb. MethodsMale BALB/c mice were intranasally administered OVA and AP for 6 and 12 weeks to induce ECRSwNP. The resultant ECRSwNP mouse model underwent histological assessment, cytokine analysis of nasal lavage fluid, olfactory behavioral tests, and gene expression profiling to identify neuroinflammatory markers within the olfactory bulb. ResultsThe developed mouse model exhibited substantial eosinophil infiltration, increased levels of inflammatory cytokines in nasal lavage fluid, and confirmed olfactory dysfunction through behavioral assays. Furthermore, olfactory bulb inflammation and reduced mature olfactory sensory neurons were observed in the model. ConclusionThis study successfully established a validated mouse model of ECRSwNP with olfactory dysfunction within a remarkably short span of 6 weeks, providing a valuable tool for investigating the pathogenesis and potential therapies for this condition. The model offers an efficient approach for future research in CRSwNP and olfactory dysfunction.

Increased Nasal Blimp1 + Treg Cells After Sublingual Immunotherapy Reflect the Efficacy of Treatment in Allergic Rhinitis.

Allergen-specific immunotherapy (AIT) plays a pivotal role in altering the immune status and tissue responses in allergic rhinitis (AR). This study focuses on the impact of sublingual immunotherapy (SLIT) involving dust mite drops, exploring the modulation of regulatory Tcells (Treg) and their specific marker, BLIMP1, in the nasal mucosa. Immune cells were isolated from nasal lavage fluid of patients with AR undergoing SLIT (n = 94). Treg cells were analyzed for BLIMP1 expression, and chemokine levels associated with Treg recruitment were assessed using Luminex assay. Patients were categorized on the basis of SLIT efficacy and followed for changes after discontinuation. SLIT induced a significant increase in nasal Treg cells (7.09 ± 2.59% vs. 0.75 ± 0.27%, P < 0.0001). BLIMP1 expression in Treg cells notably increased after SLIT (0.36 ± 0.22% to 16.86 ± 5.74%, P < 0.0001). Ineffective SLIT cases exhibited lower levels of nasal Treg and Blimp1 + Treg cells (both P < 0.0001). Receiver operating characteristic (ROC) analysis confirmed their potential as efficacy predictors (AUC = 0.908 and 0.968, respectively). SLIT discontinuation led to a significant reduction in Treg and Blimp1 + Treg cells (P < 0.001), emphasizing their maintenance during treatment. Pro-inflammatory cytokines decreased (P < 0.001), while CCL2 associated with Treg recruitment increased (P = 0.0015). Elevated nasal Blimp1 + Treg cells serve as a predictive biomarker for SLIT responsiveness in pediatric AR. Their influence on immunotherapy effectiveness contributes to a nuanced understanding of SLIT mechanisms, allowing for disease stratification and personalized treatment plans. This study offers scientific support for predicting SLIT efficacy, enhancing the prospects of improved treatment outcomes in AR.

Unraveling the link between draught and upper respiratory mucosal immunity: Assessing lysozyme and S-lgA concentrations in nasal lavage fluid

The purpose of this study is to investigate the effect of draught on upper respiratory tract mucosal immunity, by assessing concentrations of lysozyme and secretory immunoglobulin A (S-IgA) in nasal lavage fluid. A total of 26 subjects were recruited and experienced 4 experiment conditions combined with two ambient temperatures (24 °C and 28 °C) and two air velocities towards the nape (0 m/s and 1 m/s). Physiological parameters, and subjective questionnaires (i.e., thermal sensation vote (TSV), thermal comfort vote (TCV), and air movement vote (AMV)) were also collected. Our findings revealed that physiological parameters fluctuated significantly under 24 °C, 1 m/s (p < 0.05). Significant decreases in lysozyme concentration occurred under both 24 °C, 1 m/s (p = 0.003) and 24 °C, 0 m/s (p = 0.017). S-IgA concentrations significantly decreased after one-day lag (p = 0.028) under 24 °C, 1 m/s. When TSV deviated from neutral, lysozyme concentrations decreased, especially when the TSV was [-3, −1.5) (p = 0.01). The S-IgA concentration increased when subjects felt slightly uncomfortable and decreased steadily for further discomfort. The proportion of subjects with decreased immune biomarker levels was minimized in the neutral TSV zone. The findings suggest that under the investigated scenarios, cold draught can suppress respiratory immunity by altering thermal sensations, with effects potentially persisting beyond exposure duration. Ensuring a neutral and comfortable thermal environment is pivotal for maintaining immunity stability. However, more experiments under a wider range of thermal parameters need to be performed to prove the robustness of current results.

Preparation and immunogenicity evaluation of C-HapS-P6 fusion protein vaccine against nontypeable Haemophilus influenzae in mice

Nontypeable Haemophilus influenzae (NTHi) is the dominant pathogen in several infectious diseases. Currently the use of antibiotics is the main intervention to prevent NTHi infections, however with the emergence of drug resistant strains, it has compromised the treatment of respiratory infections with antibiotics. Therefore there is an urgent need to develop a safe and effective vaccine to prevent NTHi infections. We investigate the potential of C-HapS-P6 fusion protein as a vaccine for treating NTHi in murine models. PGEX-6P2/C-HapS-P6 fusion gene was constructed using overlap extension polymerase chain reaction. The recombined plasmid was transformed into Escherichia coli for protein expression. The mice were subjected to intraperitoneal immunization using purified antigens. Immunoglobulin (Ig) G in serum samples and IgA in nasal and lung lavage fluids were analyzed using enzyme-linked immunosorbent assay. Cytokine release and proliferation capacity of splenic lymphocytes in response to antigens were measured in vitro. The protective effect of the C-HapS-P6 protein against NTHi infection was evaluated by NTHi count and histological examination. The data showed that the C-HapS-P6 fusion protein increased significantly the levels of serum IgG and nasal and lung IgA, and promoted the release of interleukin (IL)-2, interferon-ϒ, IL-4, IL-5, and IL-17 and the proliferation of splenic lymphocytes compared with C-HapS or P6 protein treatment alone. Moreover, C-HapS-P6 effectively reduced the NTHi colonization in the nasopharynx and lungs of mice. In conclusion, our results demonstrated that the C-HapS-P6 fusion protein vaccine can significantly enhance humoral and cell immune responses and effectively prevent against NTHi infection in the respiratory tract in murine models.

Proteomic and metabolomic proof of concept for unified airways in chronic rhinosinusitis and asthma

BackgroundThe pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) with comorbid asthma remains unclear. ObjectiveTo assess upper and lower airway unity and identify a possible common pathogenesis in CRSwNP with asthma. MethodsThis study analyzed the expression of proteins and metabolites in nasal lavage fluid cells (NLFCs) and induced sputum cells (ISCs). Differentially expressed proteins and their function-related metabolites in the upper and lower airways of patients having CRSwNP with or without asthma were identified; relevant signaling pathways were analyzed, and key pathway-related proteins were identified. Parallel reaction monitoring was used to verify these target proteins. ResultsProtein or metabolite expression between NLFCs and ISCs was highly correlated and conservative on the basis of expression profiles and weighted gene coexpression network analysis. There were 17 differentially coexpressed proteins and their function-related 13 metabolites that were identified in the NLFCs and ISCs of CRSwNP, whereas 11 proteins and 11 metabolites were identified in CRSwNP with asthma. An asthma pathway was involved in the copathogenesis of upper and lower airways in whether CRSwNP or CRSwNP with asthma. The asthma pathway-related proteins proteoglycan 2 and eosinophil peroxidase, as the core of the protein-metabolism interaction networks between the upper and lower airways, were both highly coexpressed in NLFCs and ISCs in patients having either CRSwNP or CRSwNP with asthma by parallel reaction monitoring validation. ConclusionProteomics and metabolomics reveal upper and lower airway unity. Asthma pathway-related proteins proteoglycan 2 and eosinophil peroxidase from the upper airway could be used to assess the potential risk of lower airway dysfunction in CRSwNP.

Chaenomeles sinensis Extract Ameliorates Ovalbumin-Induced Allergic Rhinitis by Inhibiting the IL-33/ST2 Axis and Regulating Epithelial Cell Dysfunction.

Chaenomeles sinensis has traditionally been used as an herbal medicine due to its characteristics that protect against inflammation, hypertension, and mutagenesis. However, the effect of Chaenomeles sinensis extract (CSE) on allergic rhinitis (AR) and its underlying mechanisms have yet to be thoroughly investigated. The current study explored the likely effect of CSE on AR in an ovalbumin (OVA)-induced AR mouse model. To this end, OVA-specific immunoglobulins, nasal symptoms, cytokine production, the infiltration of inflammatory cells, and nasal histopathology were assessed to determine the role of CSE against AR. The supplementation of CSE was found to suppress OVA-specific IgE, while OVA-specific IgG2a was increased in the serum. Further, CSE ameliorated the production of T helper type 2 (Th2) cytokines whereas it increased Th1 cytokine levels in nasal lavage fluid. Moreover, the CSE treatment group exhibited significant inhibition of IL-33/ST2 signaling. Subsequently, CES reversed the OVA-induced enhancement of epithelial permeability and upregulated E-cadherin, thus indicating that CES plays a protective role on epithelial barrier integrity. Altogether, the oral administration of CSE effectively controlled allergic response by restricting the buildup of inflammatory cells, enhancing nasal and lung histopathological traits, and regulating cytokines associated with inflammation. Collectively, the results show that the supplementation of CSE at different doses effectively regulated AR, thus suggesting the therapeutic efficiency of CSE in suppressing airway diseases.

MicroRNA-155 is a critical regulator of regulatory T cells in OM-85 Broncho-Vaxom treated experimental models of allergic rhinitis

&lt;abstract&gt;&lt;sec&gt; &lt;title&gt;Background&lt;/title&gt; &lt;p&gt;Bacterial lysates could alleviate the clinical symptoms of allergic rhinitis (AR) and decrease the recurrent rate of AR through regulation of regulatory T cell (Treg) cells. However, the molecular regulatory mechanisms of bacterial lysates to Treg are still unclear.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Objective&lt;/title&gt; &lt;p&gt;We aimed to investigate the importance of microRNA-155 (miR-155) to Treg cells function in OM-85 Broncho-Vaxom (OM-85 BV) treated experimental mouse models of AR.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Methods&lt;/title&gt; &lt;p&gt;AR mouse models were established and treated by intranasal administration of OM-85 BV to investigate the role of bacteria lysate for Treg cell function. The proliferation of Treg cells in peripheral blood was examined. The mRNA levels of IL-10, transforming growth factor-β (TGF-β) were examined by real-time PCR. miR-155 mimics and inhibitor were used to verify the role of miR-155 for Treg cells function.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Results&lt;/title&gt; &lt;p&gt;OM-85 BV, miR-155 mimics or their combination reduced total cells, lymphocytes, neutrophils and eosinophils in nasal lavage fluid of AR mouse models and improved allergic symptoms. OM-85 BV promoted the proliferation of Treg and the expression of Foxp3, IL-10 and TGF-β both &lt;italic&gt;in vivo&lt;/italic&gt; and &lt;italic&gt;in vitro&lt;/italic&gt;. The miR-155 enhanced the proliferation and function of Treg.&lt;/p&gt; &lt;/sec&gt;&lt;sec&gt; &lt;title&gt;Conclusions&lt;/title&gt; &lt;p&gt;MiR-155 promotes Treg cells function in OM-85 BV bacteria lysate treated experimental models of AR and alleviate the upper airway allergic inflammation in AR mice.&lt;/p&gt; &lt;/sec&gt;&lt;/abstract&gt;

Immune response and severity of Omicron BA.5 reinfection among individuals previously infected with different SARS-CoV-2 variants.

COVID-19 continues to spread worldwide, with an increasing number of individuals experiencing reinfection after recovering from their primary infection. However, the nature and progression of this infection remain poorly understood. We aimed to investigate the immune response, severity and outcomes of Omicron BA.5 reinfection among individuals previously infected with different SARS-CoV-2 variants. We enrolled 432 COVID-19 cases who had experienced prior infection with the ancestral SARS-CoV-2 virus, Delta variant or Omicron BA.2 variant between January 2020 and May 2022 in Guangzhou, China. All cases underwent follow-up from March to April, 2023 through telephone questionnaires and clinical visits. Nasal lavage fluid and peripheral blood were collected to assess anti-RBD IgA, anti-RBD IgG and virus-specific IFN-γ secreting T cells. Our study shows that 73.1%, 56.7% and 12.5% of individuals with a prior infection of the ancestral virus, Delta or Omicron BA.2 variant experienced reinfection with the BA.5 variant, respectively. Fever, cough and sore throat were the most common symptoms of BA.5 reinfection, with most improving within one week and none progressing to a critical condition. Compared with individuals without reinfection, reinfected patients with a prior Delta infection exhibited elevated levels of nasal anti-RBD IgA, serum anti-RBD IgG and IFN-γ secreting T cells, whereas there was no noticeable change in reinfected individuals with a prior BA.2 infection. These results suggest that BA.5 reinfection is common but severe outcomes are relatively rare. Reinfection with a novel SARS-CoV-2 variant different from the prior infection may induce a more robust immune protection, which should be taken into account during vaccine development.

Nasal instillation of povidone-iodine ameliorates ongoing mucosal inflammation in a pre-sensitized murine model of Der p1-induced allergic rhinitis.

Interleukin(IL)-33, when cleaved into smaller fragments by proteases, becomes hyperactive, contributing to allergic inflammation. Povidone-iodine (PVP-I) is an iodine-based compound that exhibits antimicrobial properties and inhibits proteases. This study aimed to investigate whether PVP-I treatment inhibits IL-33 cleavage, improves allergic rhinitis (AR) symptoms, and suppresses allergic inflammation in a mouse model. In vitro experiments using full-length recombinant human IL-33 and allergens, including house dust mites or Dermatophagoides pteronyssinus 1, were conducted using western blotting. Fifty BALB/c mice were divided into five groups: control (CON), AR with phosphate-buffered saline treatment (AR), PVP-I treatment (AR+PVP), trans-epoxysuccinyl-L-leucylamido(4-guanidino)butane (E64) treatment (AR+E64), and dexamethasone treatment (AR+Dexa). Nasal symptom scores, including rubbing and sneezing, were measured. The cytokine levels in the nasal lavage fluid (NLF) and the concentration of immunoglobulins in the blood serum were assessed. Nasal mucosa from each group was used for reverse transcriptase-polymerase chain reaction (RT-PCR) and histological analyses were conducted. PVP-I treatment reduced nasal symptoms, suppressed allergic inflammation, and decreased the levels of IL-33, IL-5, and IL-13 in the NLF and total immunoglobulin E (IgE) and specific IgE in the serum. Histopathological analysis revealed a reduction in the number of eosinophils and goblet cells in the nasal mucosa of the AR+PVP group when compared to the AR group. RT-PCR and immunofluorescence staining confirmed the downregulation of genes and proteins associated with allergic inflammation. These findings suggest that nasal irrigation with PVP-I may be a promising therapeutic option for managing AR by inhibiting IL-33 activation and suppressing allergic inflammation.

Differential transcriptomic alterations in nasal versus lung tissue of acrolein-exposed rats

Introduction: Acrolein is a significant component of anthropogenic and wildfire emissions, as well as cigarette smoke. Although acrolein primarily deposits in the upper respiratory tract upon inhalation, patterns of site-specific injury in nasal versus pulmonary tissues are not well characterized. This assessment is critical in the design of in vitro and in vivo studies performed for assessing health risk of irritant air pollutants.Methods: In this study, male and female Wistar-Kyoto rats were exposed nose-only to air or acrolein. Rats in the acrolein exposure group were exposed to incremental concentrations of acrolein (0, 0.1, 0.316, 1 ppm) for the first 30 min, followed by a 3.5 h exposure at 3.16 ppm. In the first cohort of male and female rats, nasal and bronchoalveolar lavage fluids were analyzed for markers of inflammation, and in a second cohort of males, nasal airway and left lung tissues were used for mRNA sequencing.Results: Protein leakage in nasal airways of acrolein-exposed rats was similar in both sexes; however, inflammatory cells and cytokine increases were more pronounced in males when compared to females. No consistent changes were noted in bronchoalveolar lavage fluid of males or females except for increases in total cells and IL-6. Acrolein-exposed male rats had 452 differentially expressed genes (DEGs) in nasal tissue versus only 95 in the lung. Pathway analysis of DEGs in the nose indicated acute phase response signaling, Nrf2-mediated oxidative stress, unfolded protein response, and other inflammatory pathways, whereas in the lung, xenobiotic metabolism pathways were changed. Genes associated with glucocorticoid and GPCR signaling were also changed in the nose but not in the lung.Discussion: These data provide insights into inhaled acrolein-mediated sex-specific injury/inflammation in the nasal and pulmonary airways. The transcriptional response in the nose reflects acrolein-induced acute oxidative and cytokine signaling changes, which might have implications for upper airway inflammatory disease susceptibility.

Residual nasal polyp tissue following dupilumab therapy is associated with periostin-associated fibrosis.

Dupilumab, an anti-interleukin-4 receptor alpha monoclonal antibody, is a new treatment for severe uncontrolled chronic rhinosinusitis with nasal polyps. However, data on the effect of dupilumab on histological changes in nasal polyp tissue are lacking. We aimed to investigate the effect of dupilumab on real-life clinical conditions and nasal polyp tissues from patients with eosinophilic chronic rhinosinusitis (ECRS), which is a refractory subtype. We conducted an open-label, prospective, observational, single-centre study on 63 patients with refractory ECRS on the basis of the criteria of the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis Study. These patients had a history of surgery and received dupilumab for 24weeks. Patient-reported sinonasal symptoms, T&T olfactometry and nasal polyp scores were prospectively evaluated. In 23 patients with residual nasal polyps following dupilumab treatment, changes in systemic and local periostin expression, and total collagen deposition in nasal polyp tissues were investigated before and after dupilumab administration. Dupilumab rapidly improved sinonasal symptoms and reduced the nasal polyp score 24weeks after initiation. 40 (63.5%) patients had resolution of nasal polyps, but the reduction was limited in the remaining 23 (36.5%) patients. Periostin expression in serum and nasal lavage fluid was decreased, whereas periostin and the total collagen deposition area in subepithelial tissues in residual nasal polyps were enhanced after dupilumab administration. Dupilumab improves sinonasal symptoms and reduces the nasal polyp score in refractory ECRS. Periostin-associated tissue fibrosis may be involved in the differential effect of dupilumab on nasal polyp reduction.

Metabolomics of nasal lavage fluid in patients with allergic rhinitis treated by Xiaoqinglong Decoction

This study used nasal lavage fluid for metabolomics to explore its feasibility, and applied it to the clinical metabolomics study of Xiaoqinglong Decoction in the treatment of allergic rhinitis(AR), aiming to investigate the molecular mechanism of Xiaoqing-long Decoction in the treatment of AR through differential changes in local nasal metabolism. AR patients were selected as the research subjects, and nasal lavage fluid was collected as the sample. Metabolomics analysis using liquid chromatography-mass spectrometry was performed on normal group, AR group, and Xiaoqinglong Decoction group. The differences in metabolic profiles among the groups were compared using principal component analysis and partial least squares discriminant analysis, and differential metabolites were identified and subjected to corresponding metabolic pathway analysis. The results showed that Xiaoqinglong Decoction significantly improved the symptoms of AR patients. The metabolomics analysis revealed 20 differential metabolites between AR group and Xiaoqinglong Decoction group. The core metabolite with a trending return in comparison to normal group was trimethyladipic acid. The metabolites were involved in multiple pathways, including β-alanine metabolism, glutathione metabolism, and phenylalanine, tyrosine, and tryptophan biosynthesis. The feasibility of applying nasal lavage fluid in nasal metabolomics was preliminarily demonstrated. Differential metabolites and enriched pathways in the treatment of AR patients with Xiaoqinglong Decoction were identified, indicating that it may improve rhinitis symptoms through the regulation of various metabolites, including antioxidant effects and correction of Th1/Th2 imbalance.

Production of pro-inflammatory mediators stimulated by exposure of poultry house workers to airborne dust particulates.

Poultry house employees spend a significant part of their work shift being exposed to airborne particulate pollutants. The aim of this study was to assess their exposure at different stages of chicken production cycle, based on quantification of pro-inflammatory mediators (IL-1β, IL-6, IL-8, and TNFα) in nasal lavage (NAL) samples. The concentrations of airborne dust at 3 different stages of the production cycle (i.e. empty poultry house, with 7- and 42-day-old chickens) were stationary measured using Grimm spectrometer, as well as CIS and Button samplers. The dust collected by the latter 2 samplers was analyzed for endotoxin and (1→3)-β-D-glucan content. NAL samples were collected from employees after their work shift to determine the pro-inflammatory mediator levels. The maximum particulate aerosol, endotoxin, and (1→3)-β-D-glucan concentrations at workplaces reached the levels of 4.12mg/m3, 45.21 ng/m3, and 56.54 ng/m3, respectively. The IL-1β, IL-6, and IL-8 concentrations in NAL samples ranged between 0.62-18.12 pg/mL, <0.70-25.37 pg/mL, and <3.50-259.5 pg/mL, respectively. All TNFα levels were below 4pg/mL. There were no significant differences between these cytokine concentrations in NAL samples collected at different stages of chicken breeding in either 'winter' or 'summer' seasons. Inhalation stimulation with poultry dust containing endotoxins and (1→3)-β-D-glucans resulted in the production of pro-inflammatory mediators, which proves the course of immunological processes in the exposed employees that may lead to adverse effects. The use of nasal lavage fluid in the control of such exposure confirms that NAL analysis is a reliable laboratory tool for assessing the impact of poultry dust on exposed farm workers.

Role of NLRP3 in the exacerbation of ozone-induced allergic rhinitis

ObjectiveAllergic rhinitis (AR) is an immunoglobulin E (IgE)-mediated inflammatory disorder of the nasal mucosa, and the impact of ozone on AR is gaining increasing attention. Although NOD-like receptor thermal protein domain associated protein 3 (NLRP3) plays a crucial role in the pathogenesis of AR, its regulatory mechanisms in ozone-induced exacerbation remain unclear. Therefore, we explored the impact of ozone inhalation on inflammation in AR and investigated the regulatory mechanisms involving NLRP3. MethodsFifty female Sprague–Dawley rats were selected and divided into five groups: normal control (NC), normal with ozone exposure (NE), AR model, AR with ozone exposure (ARE), and ARE treated with the NLRP3 inhibitor MCC950 (ARE+MCC950). Behavioral changes were observed in the rats, and the expression of NLRP3, active-caspase 1, and GSDMD-N was detected by western blotting. The expression levels of interleukin (IL)− 4, IL-5, IL-13, IL-1β, and ovalbumin-specific IgE (OVA-sIgE) in nasal lavage fluid as well as IL-6 in the serum were measured by ELISA. The expression and distribution of NLRP3 and IL-1β in nasal mucosal tissue were detected by immunohistochemistry, and pathological changes and eosinophilic infiltration in nasal mucosal tissue were observed by hematoxylin and eosin (HE) staining. The effects of ozone exposure on inflammation in the nasal mucosal tissue of rats with AR and the relationship between NLRP3 and inflammation were analyzed. ResultsUpregulation of NLRP3 was observed in the AR rat model, and ozone further aggravated the expression of NLRP3 in the nasal mucosal tissue. Compared to the AR, NC, and NE groups, NLRP3 inflammasomes were activated in the ARE group, and the expression levels of related indexes active-caspase 1 and GSDMD-N were significantly increased; the expression levels of Th2 inflammatory factors IL-4, IL-5, IL-13, and OVA-sIgE were increased, and inflammatory factors such as IL-1β and IL-6 expression was also significantly increased. HE staining revealed that ozone aggravated damage to the nasal mucosal tissue in AR. Compared with the ARE group, the expression of NLRP3 inflammasomes was downregulated, sneezing and scratching symptoms were reduced, inflammatory indicators in nasal lavage fluid were decreased, and nasal mucosal tissue damage was alleviated in rats in the ARE+MCC950 group. ConclusionOzone exposure significantly increased the inflammatory response in an animal model of AR. MCC950 can selectively inhibit the expression of NLRP3, inhibit the activity of inflammasomes, and reduce nasal mucosal inflammation by regulating the NLRP3-caspase-1-IL-1β pathway.

Alteration of Neural Network and Hippocampal Slice Activation through Exosomes Derived from 5XFAD Nasal Lavage Fluid.

Exosomes, key mediators of intercellular transmission of pathogenic proteins, such as amyloid-beta and tau, significantly influence the progression and exacerbation of Alzheimer's disease (AD) pathology. Present in a variety of biological fluids, including cerebrospinal fluid, blood, saliva, and nasal lavage fluid (NLF), exosomes underscore their potential as integral mediators of AD pathology. By serving as vehicles for disease-specific molecules, exosomes could unveil valuable insights into disease identification and progression. This study emphasizes the imperative to investigate the impacts of exosomes on neural networks to enhance our comprehension of intracerebral neuronal communication and its implications for neurological disorders like AD. After harvesting exosomes derived from NLF of 5XFAD mice, we utilized a high-density multielectrode array (HD-MEA) system, the novel technology enabling concurrent recordings from thousands of neurons in primary cortical neuron cultures and organotypic hippocampal slices. The ensuing results revealed a surge in neuronal firing rates and disoriented neural connectivity, reflecting the effects provoked by pathological amyloid-beta oligomer treatment. The local field potentials in the exosome-treated hippocampal brain slices also exhibited aberrant rhythmicity, along with an elevated level of current source density. While this research is an initial exploration, it highlights the potential of exosomes in modulating neural networks under AD conditions and endorses the HD-MEA as an efficacious tool for exosome studies.

Mitochondrial dynamics modulate the allergic inflammation in a murine model of allergic rhinitis.

Allergic rhinitis (AR) is a common allergic disorder, afflicting thousands of human beings. Aberrant mitochondrial dynamics are important pathological elements for various immune cell dysfunctions and allergic diseases. However, the connection between mitochondrial dynamics and AR remains poorly understood. This study aimed to determine whether mitochondrial dynamics influence the inflammatory response in AR. In the present study, we established a murine model of AR by sensitization with ovalbumin (OVA). Then, we investigated the mitochondrial morphology in mice with AR by transmission electron microscopy and confocal fluorescence microscopy, and evaluated the role of Mdivi-1 (an inhibitor of mitochondrial fission) on allergic symptoms, inflammatory responses, allergic-related signals, and reactive oxygen species formation. There was a notable enhancement in mitochondrial fragmentation in the nasal mucosa of mice following OVA stimulation, whereas Mdivi-1 prevented aberrant mitochondrial morphology. Indeed, Mdivi-1 alleviated the rubbing and sneezing responses in OVA-sensitized mice. Compared with vehicle-treated ones, mice treated with Mdivi-1 exhibited a reduction in interleukin (IL)-4, IL-5, and specific IgE levels in both serum and nasal lavage fluid, and shown an amelioration in inflammatory response of nasal mucosa. Meanwhile, Mdivi-1 treatment was associated with a suppression in JAK2 and STAT6 activation and reactive oxygen species generation, which act as important signaling for allergic response. Our findings reveal mitochondrial dynamics modulate the allergic responses in AR. Mitochondrial dynamics may represent a promising target for the treatment of AR.

Fallopia japonica Root Extract Ameliorates Ovalbumin-Induced Airway Inflammation in a CARAS Mouse Model by Modulating the IL-33/TSLP/NF-κB Signaling Pathway.

Fallopia japonica (Asian knotweed) is a medicinal herb traditionally used to treat inflammation, among other conditions. However, the effects of F. japonica root extract (FJE) on airway inflammation associated with combined allergic rhinitis and asthma (CARAS) and the related mechanisms have not been investigated. This study examined the effect of FJE against CARAS in an ovalbumin (OVA)-induced CARAS mouse model. Six-week-old male BALB/c mice were randomly segregated into six groups. Mice were sensitized intraperitoneally with OVA on days 1, 8, and 15, and administered saline, Dexamethasone (1.5 mg/kg), or FJE (50, 100, or 200 mg/kg) once a day for 16 days. Nasal symptoms, inflammatory cells, OVA-specific immunoglobulins, cytokine production, mast cell activation, and nasal histopathology were assessed. Administration of FJE down-regulated OVA-specific IgE and up-regulated OVA-specific IgG2a in serum. FJE reduced the production of T helper (Th) type 2 cytokines, and the Th1 cytokine levels were enhanced in nasal and bronchoalveolar lavage fluid. Moreover, FJE positively regulated allergic responses by reducing the accumulation of inflammatory cells, improving nasal and lung histopathological characteristics, and inhibiting inflammation-associated cytokines. FJE positively modulated the IL-33/TSLP/NF-B signaling pathway, which is involved in regulating inflammatory cells, immunoglobulin levels, and pro-inflammatory cytokines at the molecular level.