Targeting lysyl oxidase like 2 attenuates OVA-induced airway remodeling partly via the AKT signaling pathway.

BACKGROUND: Airway epithelium is an important component of airway structure and the initiator of airway remodeling in asthma. The changes of extracellular matrix (ECM), such as collagen deposition and structural disturbance, are typical pathological features of airway remodeling. Thus, identifying key mediators that derived from airway epithelium and capable of modulating ECM may provide valuable insights for targeted therapy of asthma. METHODS: The datasets from Gene Expression Omnibus database were analyzed to screen differentially expressed genes in airway epithelium of asthma. We collected bronchoscopic biopsies and serum samples from asthmatic and healthy subjects to assess lysyl oxidase like 2 (LOXL2) expression. RNA sequencing and various experiments were performed to determine the influences of LOXL2 knockdown in ovalbumin (OVA)-induced mouse models. The roles and mechanisms of LOXL2 in bronchial epithelial cells were explored using LOXL2 small interfering RNA, overexpression plasmid and AKT inhibitor. RESULTS: Both bioinformatics analysis and further experiments revealed that LOXL2 is highly expressed in airway epithelium of asthmatics. In vivo, LOXL2 knockdown significantly inhibited OVA-induced ECM deposition and epithelial-mesenchymal transition (EMT) in mice. In vitro, the transfection experiments on 16HBE cells demonstrated that LOXL2 overexpression increases the expression of N-cadherin and fibronectin and reduces the expression of E-cadherin. Conversely, after silencing LOXL2, the expression of E-cadherin is up-regulated. In addition, the remodeling and EMT process that induced by transforming growth factor-ß1 could be enhanced and weakened after LOXL2 overexpression and silencing in 16HBE cells. Combining the RNA sequencing of mouse lung tissues and experiments in vitro, LOXL2 was involved in the regulation of AKT signaling pathway. Moreover, the treatment with AKT inhibitor in vitro partially alleviated the consequences associated with LOXL2 overexpression. CONCLUSIONS: Taken together, the results demonstrated that epithelial LOXL2 plays a role in asthmatic airway remodeling partly via the AKT signaling pathway and highlighted the potential of LOXL2 as a therapeutic target for airway remodeling in asthma.

Breast milk-mediated exposure to dioxins and antigen in infancy enhances antigen-specific antibody production capacity in adulthood in mice.

The immune system is sensitive to many chemicals. Among dioxin compounds, 2,3,7,8-tetrachlorodizenzo-p-dioxin (TCDD) is the most toxic environmental pollutant. The effects of perinatal maternal exposure to dioxins may persist into childhood. However, there have been no reports to date on the effects of exposure to dioxins during infancy, when the immune organs are developing. Therefore, we investigated the effects of TCDD and antigen exposure during lactation on immune function, especially antibody production capacity, in adult mice. Beginning the day after delivery, lactating mothers were orally administered TCDD or a mixture of TCDD and ovalbumin (OVA) daily for 4 weeks, until the pups were weaned. At 6 weeks of age, progeny mice were orally administered OVA daily for 10 weeks, while non-progeny mice were orally administered OVA or a mixture of TCDD and OVA daily for 10 weeks. Production of serum OVA-specific IgG was examined weekly. The amount of TCDD transferred from the mother to the progeny via breast milk was determined by measuring TCDD in the gastric contents of the progeny. A trend toward increasing IgA titer was observed in TCDD-treated mice, and production of IgE was observed only in progeny whose mothers were treated with TCDD and OVA. The results suggest that exposure to TCDD and OVA in breast milk can affect immune function in newborns.

Construction of lymph nodes-targeting tumor vaccines by using the principle of DNA base complementary pairing to enhance anti-tumor cellular immune response.

Tumor vaccines, a crucial immunotherapy, have gained growing interest because of their unique capability to initiate precise anti-tumor immune responses and establish enduring immune memory. Injected tumor vaccines passively diffuse to the adjacent draining lymph nodes, where the residing antigen-presenting cells capture and present tumor antigens to T cells. This process represents the initial phase of the immune response to the tumor vaccines and constitutes a pivotal determinant of their effectiveness. Nevertheless, the granularity paradox, arising from the different requirements between the passive targeting delivery of tumor vaccines to lymph nodes and the uptake by antigen-presenting cells, diminishes the efficacy of lymph node-targeting tumor vaccines. This study addressed this challenge by employing a vaccine formulation with a tunable, controlled particle size. Manganese dioxide (MnO2) nanoparticles were synthesized, loaded with ovalbumin (OVA), and modified with A50 or T20 DNA single strands to obtain MnO2/OVA/A50 and MnO2/OVA/T20, respectively. Administering the vaccines sequentially, upon reaching the lymph nodes, the two vaccines converge and simultaneously aggregate into MnO2/OVA/A50-T20 particles through base pairing. This process enhances both vaccine uptake and antigen delivery. In vitro and in vivo studies demonstrated that, the combined vaccine, comprising MnO2/OVA/A50 and MnO2/OVA/T20, exhibited robust immunization effects and remarkable anti-tumor efficacy in the melanoma animal models. The strategy of controlling tumor vaccine size and consequently improving tumor antigen presentation efficiency and vaccine efficacy via the DNA base-pairing principle, provides novel concepts for the development of efficient tumor vaccines.

Improved biodistribution and enhanced immune response of subunit vaccine using a nanostructure formed by self-assembly of ascorbyl palmitate.

New adjuvant strategies are needed to improve protein-based subunit vaccine immunogenicity. We examined the potential to use nanostructure of 6-O-ascorbyl palmitate to formulate ovalbumin (OVA) protein and an oligodeoxynucleotide (CpG-ODN) (OCC). In mice immunized with a single dose, OCC elicited an OVA-specific immune response superior to OVA/CpG-ODN solution (OC). Rheological studies demonstrated OCC's self-assembling viscoelastic properties. Biodistribution studies indicated that OCC prolonged OVA and CpG-ODN retention at injection site and lymph nodes, reducing systemic spread. Flow-cytometry assays demonstrated that OCC promoted OVA and CpG-ODN co-uptake by Ly6ChiCD11bhiCD11c+ monocytes. OCC and OC induced early IFN-γ in lymph nodes, but OCC led to higher concentration. Conversely, mice immunized with OC showed higher serum IFN-γ concentration compared to those immunized with OCC. In mice immunized with OCC, NK1.1+ cells were the IFN-γ major producers, and IFN-γ was essential for OVA-specific IgG2c switching. These findings illustrate how this nanostructure improves vaccine's response.

3-carene supresses inflammatory cytokine interleukin-4, interleukin-5 and interleukin-13 in a murine model of asthma.

Asthma is a common airway disease associated with allergic inflammation. Environmental factors, such as pollens, pollution, insect-borne antigens, or commercial chemicals, cause this disease. The common symptoms of this airway allergic reaction are increasing mucus, narrowing of the airway wall, coughing, and chest tightness. Medications, such as steroids, alleviate the disease but with severe side effects. Several studies have reported the anti-inflammatory effects of tree-based essential oil components, particularly 3-carene. Therefore, this study used 3-carene to determine if it alleviates asthmatic symptoms in the murine model. First, BALB/c mice were sensitized to an ovalbumin and aluminium hydroxide mixture on day 7th and 14th. From days 21st to 23rd, the mice were challenged with 3-carene and budesonide. The lung trachea, plasma, and bronchiolar lavage fluid (BAL fluid) were collected on day 24. The 3-carene treatment suppressed the cytokine gene expression, such as interleukin-4 (IL-4), IL-5, and IL-13, reducing the lung epithelial cell thickness in the asthmatic model. These results suggest that essential oil 3-carene has an anti-asthmatic effect.

[The effects and mechanisms of Gefitinib on airway inflammation and airway remodeling in C57BL/6 mice with asthma].

Objective: To investigate the effects of the epidermal growth factor receptor(EGFR) inhibitor Gefitinib on airway inflammation and airway remodelling in asthmatic C57BL/6 mice, and to analyze its possible mechanisms. Methods: Male C57BL/6 mice, aged 6-8 weeks, were randomly assigned into five groups: Group A (control group), Group B (asthma group), Group C (asthma+20 mg/kg gefitinib group), Group D (asthma+40 mg/kg gefitinib group), and Group E (40 mg/kg gefitinib group), with seven mice per group. Mice were sensitized by intraperitoneal injection of a mixture of 0.2 ml solution containing OVA and Al(OH)3 [20 µg OVA+2 mg Al(OH)3 dissolved in 0.2 ml of physiological saline] at Day 0 and 14. Starting from Day 25 to 31, Group B, C, and D were challenged with nebulization of 1% OVA solution (8 ml) to induce asthma, once a day for approximately 40 minutes, with continuous aerosolization for 7 days. Group C and D were given 0.2 ml of Gefitinib dissolved in 0.5% carboxymethylcellulose sodium (CMCNa) by gavage half an hour before challenging, and Group E was simultaneously given with 0.2 ml of Gefitinib dissolved in 0.5% CMCNa only. Group A and B were given an equivalent volume of 0.5% CMCNa by gavage. After 24 h of final challenge, the bronchoalveolar lavage fluid (BALF) was prepared for the determination of total cell count and eosinophil count. The levels of total immune globulin E (IgE) in serum and interleukin (IL)-4, IL-5 and IL-13 in BALF and lung tissue homogenates were measured by ELISA. The mRNA expression levels of IL-4, IL-5, IL-13 in lung were measured. Immunohistochemistry and Western blot experiments were used to detect the expression levels of EGFR in lung tissues. Results: In Group B, the level of total IgE in serum, total cell count, eosinophil count, the levels of IL-4, IL-5, IL-13 in BALF and the phosphorylation of EGFR and its downstream activation in lung were higher than those in Group A (all P<0.05). The levels of total IgE in serum [(261.32±44.38) ng/ml, (194.09±52.39) ng/ml vs (1 023.70±105.51) ng/ml], total cell count [(23.70±4.08)×105/ml, (14.92±4.06)×105/ml vs (35.36±6.30)×105/ml], eosinophil count [(108.00±13.69)×104/ml, (67.00±17.28)×104/ml vs (147.86±20.06)×104/ml], IL-4 [(36.42±4.48) pg/ml, (30.45±8.12) pg/ml vs (58.72±7.17) pg/ml], IL-5 [(16.20±4.62) pg/ml, (13.38±5.14) pg/ml vs (23.46±5.38) pg/ml], IL-13 [(18.45±7.28) pg/ml, (14.33±7.70) pg/ml vs (104.12±24.66) pg/ml] in BALF of Group C and D were lower than those in Group B (all P<0.05). The levels of IL-4, IL-5, and IL-13 as well as their mRNA levels in the lung tissue of Group C and D were lower than those in Group B (all P<0.05). In Group C and D, the positive expression rate of phosphorylated epidermal growth factor receptor (p-EGFR) in lung tissue [(40.53±6.80)%, (23.60±4.42)% vs (70.78±5.36)%], p-EGFR/EGFR (61.68±7.48, 51.13±5.19 vs 105.90±11.66), phosphorylated extracellular regulated protein kinase (p-Erk)/extracellular regulated protein kinase (Erk) (75.28±7.11, 47.54±4.83 vs 98.76±4.71), and phosphorylated protein kinase B (p-Akt)/protein kinase B (Akt) (96.24±5.40, 68.52±2.73 vs 103.30±4.52) was lower than those of Group B (all P<0.05). There was no statistically significant difference in the relevant indicators between Group A and E (all P>0.05). Conclusion: Gefitinib may alleviate airway inflammation and airway remodeling in asthmatic mice by inhibiting EGFR phosphorylation and affecting the activation of downstream Erk and Akt.

Effects of polysaccharides on colonic targeting and colonic fermentation of ovalbumin-ferulic acid based emulsion.

Rutin is a polyphenol with beneficial pharmacological properties. However, its bioavailability is often compromised due to low solubility and poor stability. Encapsulation technologies, such as emulsion systems, have been proven to be promising delivery vehicles for enhancing the bioavailability of bioactive compounds. Thus, this study was proposed and designed to investigate the colonic targeting and colonic fermentation characteristics of rutin-loaded ovalbumin-ferulic acid-polysaccharide (OVA-FA-PS) complex emulsions. The results indicate that OVA-FA-PS emulsion effectively inhibits the degradation of rutin active substances and facilitates its transport of rutin to the colon. The analysis revealed that the OVA-FA-κ-carrageenan emulsion loaded with rutin exhibited superior elasticity and colon targeting properties compared to the OVA-FA-hyaluronic acid or OVA-FA-sodium alginate emulsions loaded with rutin in the composite emulsion. Additionally, it was observed that the rutin loaded within the OVA-FA-κ-carrageenan emulsion underwent degradation and was converted to 4-hydroxybenzoic acid during colonic fermentation.

Inhibition of phosphoinositide 3-kinase activity attenuates neutrophilic airway inflammation and inhibits pyrin domain-containing 3 inflammasome activation in an ovalbumin-lipopolysaccharide-induced asthma murine model.

BACKGROUND: Existing investigations suggest that the blockade of phosphoinositide 3-kinase (PI3K) activity contributes to inflammatory solution in allergic asthma, but whether this inhibition directly attenuates neutrophilic airway inflammation in vivo is still unclear. We explored the pharmacological effects of LY294002, a specific inhibitor of PI3K on the progression of neutrophilic airway inflammation and investigated the underlying mechanism. METHODS AND RESULTS: Female C57BL/6 mice were intranasally sensitized with ovalbumin (OVA) together with lipopolysaccharide (LPS) on days 0 and 6, and challenged with OVA on days 14-17 to establish a neutrophilic airway disease model. In the challenge phase, a subset of mice was treated intratracheally with LY294002. We found that treatment of LY294002 attenuates clinic symptoms of inflammatory mice. Histological studies showed that LY294002 significantly inhibited inflammatory cell infiltration and mucus production. The treatment also significantly inhibited OVA-LPS induced increases in inflammatory cell counts, especially neutrophil counts, and IL-17 levels in bronchoalveolar lavage fluid (BALF). LY294002 treated mice exhibited significantly increased IL-10 levels in BALF compared to the untreated mice. In addition, LY294002 reduced the plasma concentrations of IL-6 and IL-17. The anti-inflammatory effects of LY29402 were correlated with the downregulation of NLRP3 inflammasome. CONCLUSIONS: Our findings suggested that LY294002 as a potential pharmacological target for neutrophilic airway inflammation.

Polymeric monolithic columns based on natural wood for rapid purification of targeted protein.

With multiscale hierarchical structure, wood is suitable for a range of high-value applications, especially as a chromatographic matrix. Here, we have aimed to provide a weak anion-exchange polymeric monolithic column based on natural wood with high permeability and stability for effectively separating the targeted protein. The wood-polymeric monolithic column was synthesized by in situ polymerization of glycidyl methacrylate and ethylene glycol dimethacrylate in wood, and coupled with diethylaminoethyl hydrochloride. The wood-polymeric monolithic column can be integrated with fast-protein liquid chromatography for large-scale protein purification. According to the results, the wood-polymeric monolithic column showed high hydrophilicity, permeability and stability. Separation experiments verified that the wood-polymeric monolithic column could purify the targeted protein (spike protein of SARS-COV-2 and ovalbumin) from the mixed proteins by ion exchange, and the static adsorption capacity was 33.04 mg mL-1 and the dynamic adsorption capacity was 24.51 mg mL-1. In addition, the wood-polymerized monolithic column had good stability, and a negligible decrease in the dynamic adsorption capacity after 20 cycles. This wood-polymerized monolithic column can provide a novel, efficient, and green matrix for monolithic chromatographic columns.

Comparison of anti-allergic activities of different types of lotus seed resistant starch in OVA-induced mouse model.

Currently, evidence from observational studies suggests dietary fiber intake may be associated with decreased risk of food allergy. As a type of dietary fiber, resistant starch was also widely reported to possess anti-allergic properties. However, there is a relative paucity of studies assessing the influence of resistant starch types on their anti-allergic activity and its possible underlying mechanisms. In the current study, the anti-allergic effects of RS3-type (retrograded starch), RS4-type (chemically modified starch, cross-bonded), and RS5-type (starch-palmitic acid complex) of lotus seed resistant starch were evaluated in the OVA (100 mg/kg)-induced food allergic mice model. The results showed that oral administration of RS3 or RS4 lotus seed resistant starch (0.3 g/100 g b.w.) for 25 days significantly improved adverse symptoms of food allergy such as weight loss, increases in allergy symptom score and diarrhea rate; with significant reduction of serum specific antibody IgE, TNF-α, IL-4 levels and improved Th1/Th2 balance being observed. The mechanism may involve the regulation of lotus seed resistant starch on intestinal flora and the metabolites short-chain fatty acids and bile acids. Taken together, the findings may enhance understanding towards ameliorative effects of resistant starch on food allergy, and offer valuable insights for the exploration of novel anti-allergic bioactive compounds.

Trim27 aggravates airway inflammation and oxidative stress in asthmatic mice via potentiating the NLRP3 inflammasome.

Asthma is a prevalent chronic respiratory disease, yet understanding its ecology and pathogenesis remains a challenge. Trim27, a ubiquitination ligase belonging to the TRIM (tripartite motif-containing) family, has been implicated in regulating multiple pathophysiological processes such as inflammation, oxidative stress, apoptosis, and cell proliferation. However, the role of Trim27 in asthma has not been investigated. Our study found that Trim27 expression significantly increases in the airway epithelium of asthmatic mice. Knockdown of Trim27 expression effectively relieved ovalbumin (OVA)-induced airway hyperresponsiveness (AHR) and lung tissue histopathological changes. Moreover, Trim27 knockdown exhibited a significant reduction in airway inflammation and oxidative stress in asthmatic mice, and in vitro analysis confirmed the favorable effect of Trim27 deletion on inflammation and oxidative stress in mouse airway epithelial cells. Furthermore, our study revealed that deletion of Trim27 in MLE12 cells significantly decreased NLRP3 inflammasome activation, as evidenced by reduced expression of NLRP3, ASC, and pro-IL-1ß mRNA. This downregulation was reversed when Trim27, but not its mutant lacking ubiquitination ligase activity, was replenished in these cells. Consistent with these findings, protein levels of NLRP3, pro-caspase-1, pro-IL-1ß, cleaved-caspase-1, and cleaved-IL-1ß were higher in Trim27-replenished cells compared to cells expressing Trim27C/A. Functionally, the downregulation of IL-1ß and IL-18 levels induced by Trim27 deletion was rescued by replenishing Trim27. Overall, our findings provide evidence that Trim27 contributes to airway inflammation and oxidative stress in asthmatic mice via NLRP3 inflammasome activation, providing crucial insights into potential therapeutic interventions targeting Trim27 as a way to treat asthma.

Penicilazaphilone C alleviates allergic airway inflammation and improves the immune microenvironment by hindering the NLRP3 inflammasome.

AIMS: Penicilazaphilone C (PAC) is hypothesized to potentially serve as a therapeutic treatment for allergic airway inflammation by inhibiting the NLRP3 inflammasome and reducing oxidative stress. METHODS: An allergic asthma model was induced in female BALB/c mice of the OVA, OVA+PAC, OVA+PAC+LPS, and OVA+Dex groups by sensitizing and subsequently challenging them with OVA. The OVA+PAC and Normal+PAC groups were treated with PAC, while the OVA+PAC+LPS group also received LPS. The OVA+Dex group was given dexamethasone (Dex). Samples of serum, bronchoalveolar lavage fluid (BALF), and lung tissue were collected for histological and cytological analysis. RESULTS: Allergic mice treated with PAC or Dex showed inhibited inflammation and mucus production in the lungs. There was a decrease in the number of inflammatory cells in the BALF, lower levels of inflammatory cytokines in the serum and BALF, and a reduction in the protein expression of NLRP3, ASC, cleaved caspase-1, IL-1ß, activated gasdermin D, MPO, Ly6G, and ICAM-1. Additionally, oxidative stress was reduced, as shown by a decrease in MDA and DCF, but an increase in SOD and GSH. Treatment with PAC also resulted in a decrease in pulmonary memory CD4+ T cells and an increase in regulatory T cells. However, the positive effects seen in the PAC-treated mice were reversed when the NLRP3 inflammasome was activated by LPS, almost returning to the levels of the Sham-treated mice. SIGNIFICANCE: PAC acts in a similar way to anti-allergic inflammation as Dex, suggesting it may be a viable therapeutic option for managing allergic asthma inflammation.

Nanosized Additives: Silicon Dioxide's Potential Role in Development of Food Sensitivities in Mice.

The anticaking agent, used in a wide variety of powdered food products, interfered with immune tolerance of ovalbumin, a model antigen; and it worsened gut inflammation in a mouse model of celiac disease.

Ameliorative potential of galangin in murine model of ovalbumin-induced allergic rhinitis: a role of PI3K-PKB pathway.

OBJECTIVE: To examine the potential of galangin in a mouse model of ovalbumin (OVA)-induced allergic rhinitis (AR), as chronic AR, induced by immunoglobulin-E (IgE), leads to histamine release and nasal inflammation, and although galangin exhibits antiasthmatic and anti-inflammatory potential, its effect on AR is yet to be investigated. ANIMALS: 126 BALB/c mice. METHODS: AR induction involved sensitizing female mice with OVA (5%, 500 µL, IP) for 14 days. Post OVA challenge, the mice were divided into 7 groups (n = 18/group), including normal, AR control, montelukast (10 mg/kg), galangin (5, 10, and 20 mg/kg), and per se (galangin [20 mg/kg] treatment. Various outcomes were evaluated, including nasal symptoms, histopathology, biochemistry, and nasal lavage fluid inflammatory cytokines and signaling pathways in nasal mucosal to assess galangin potential in AR. RESULTS: In AR mice, galangin (10 and 20 mg/kg) significantly (P < .05) reduced sneezing, rubbing, and nasal discharge post-OVA challenge. Galangin treatment attenuated (P < .05) elevated serum histamine, ß-hexosaminidase, IgE, and Immunoglobulin G1 levels in AR control mice. Additionally, galangin significantly (P < .05) decreased OVA-induced alterations in IL-4, IL-6, IL-13, and interferon-γ levels in nasal lavage fluid compared to AR control mice. Western blot analysis demonstrated that galangin lowered OVA-induced AR by significantly (P < .05) downregulating the phosphorylated protein kinase B and mammalian target of rapamycin-protein expressions while markedly (P < .05) upregulating the glycogen synthase kinase-3ß protein expressions in nasal mucosal. Galangin also significantly ameliorated (P < .05) the OVA-induced histological aberrations in the nasal mucosa, reflected by reduced eosinophil infiltration, hyperplasia, and edema. CLINICAL RELEVANCE: Galangin exhibits antihistaminic and anti-inflammatory effects in AR mice by regulating IgE-mediated histamine and inflammatory release and modulating the phosphatidylinositol 3-kinase/Ak strain transforming/mammalian target of rapamycin pathways.

Deleting the mitochondrial respiration negative regulator MCJ enhances the efficacy of CD8+ T cell adoptive therapies in pre-clinical studies.

Mitochondrial respiration is essential for the survival and function of T cells used in adoptive cellular therapies. However, strategies that specifically enhance mitochondrial respiration to promote T cell function remain limited. Here, we investigate methylation-controlled J protein (MCJ), an endogenous negative regulator of mitochondrial complex I expressed in CD8 cells, as a target for improving the efficacy of adoptive T cell therapies. We demonstrate that MCJ inhibits mitochondrial respiration in murine CD8+ CAR-T cells and that deletion of MCJ increases their in vitro and in vivo efficacy against murine B cell leukaemia. Similarly, MCJ deletion in ovalbumin (OVA)-specific CD8+ T cells also increases their efficacy against established OVA-expressing melanoma tumors in vivo. Furthermore, we show for the first time that MCJ is expressed in human CD8 cells and that the level of MCJ expression correlates with the functional activity of CD8+ CAR-T cells. Silencing MCJ expression in human CD8 CAR-T cells increases their mitochondrial metabolism and enhances their anti-tumor activity. Thus, targeting MCJ may represent a potential therapeutic strategy to increase mitochondrial metabolism and improve the efficacy of adoptive T cell therapies.

Fermented Gracilaria lemaneiformis polysaccharides alleviate food allergy by regulating Treg cells and gut microbiota.

Food allergy has a significant impact on the health and well-being of individuals, affecting both their physical and mental states. Research on natural bioactive compounds, such as polysaccharides extracted from seaweeds, holds great promise in the treatment of food allergies. In this study, fermented Gracilaria lemaneiformis polysaccharides (F-GLSP) were prepared using probiotic fermentation. Probiotic fermentation of Gracilaria lemaneiformis reduces the particle size of polysaccharides. To compare the anti-allergic activity of F-GLSP with unfermented Gracilaria lemaneiformis polysaccharides (UF-GLSP), an OVA-induced mouse food allergy model was established. F-GLSP exhibited a significant reduction in OVA-specific IgE and mMCP levels in allergic mice. Moreover, it significantly inhibited Th2 differentiation and IL-4 production and significantly promoted Treg differentiation and IL-10 production in allergic mice. In contrast, UF-GLSP only reduced OVA-specific IgE and mMCP in the serum of allergic mice. Furthermore, F-GLSP demonstrated a more pronounced regulation of intestinal flora abundance compared to UF-GLSP, significantly influencing the populations of Firmicutes, Bacteroidetes, Lactobacillus, and Clostridiales in the intestines of mice with food allergy. These findings suggest that F-GLSP may regulate food allergies in mice through multiple pathways. In summary, this study has promoted further development of functional foods with anti-allergic properties based on red algae polysaccharides.

Dimethyl fumarate alleviates allergic asthma by strengthening the Nrf2 signaling pathway in regulatory T cells.

Allergic asthma is a widely prevalent inflammatory condition affecting people across the globe. T cells and their secretory cytokines are central to the pathogenesis of allergic asthma. Here, we have evaluated the anti-inflammatory impact of dimethyl fumarate (DMF) in allergic asthma with more focus on determining its effect on T cell responses in allergic asthma. By utilizing the ovalbumin (OVA)-induced allergic asthma model, we observed that DMF administration reduced the allergic asthma symptoms and IgE levels in the OVA-induced mice model. Histopathological analysis showed that DMF treatment in an OVA-induced animal model eased the inflammation in the nasal and bronchial tissues, with a particular decrease in the infiltration of immune cells. Additionally, RT-qPCR analysis exhibited that treatment of DMF in an OVA-induced model reduced the expression of inflammatory cytokine (IL4, IL13, and IL17) while augmenting anti-inflammatory IL10 and Foxp3 (forkhead box protein 3). Mechanistically, we found that DMF increased the expression of Foxp3 by exacerbating the expression of nuclear factor E2-related factor 2 (Nrf2), and the in-vitro activation of Foxp3+ Tregs leads to an escalated expression of Nrf2. Notably, CD4-specific Nrf2 deletion intensified the allergic asthma symptoms and reduced the in-vitro iTreg differentiation. Meanwhile, DMF failed to exert protective effects on OVA-induced allergic asthma in CD4-specific Nrf2 knock-out mice. Overall, our study illustrates that DMF enhances Nrf2 signaling in T cells to assist the differentiation of Tregs, which could improve the anti-inflammatory immune response in allergic asthma.

In vivo evaluations of Lactobacillus-fermented Eucheuma spinosum polysaccharides on alleviating food allergy activity.

In order to explore the in vivo anti-food allergy activity of Lactobacillus sakei subsp. sakei-fermented Eucheuma spinosum polysaccharides F1-ESP-3, an ovalbumin (OVA)-induced food allergy mouse model was established by ascites immunization and gavage. The weight, temperature, incidence of diarrhea, levels of allergic mediators and inflammatory factors in the serum of mice were analyzed. We analyzed the differentiation of mouse spleen lymphocytes and the proportion of sensitized mast cells by flow cytometry. The intestinal barrier status of mice was analyzed by intestinal pathological tissue sections and microbiota sequencing. The results showed that F1-ESP-3 could alleviate the food allergy symptoms of mice, such as hypothermia and loose stool; levels of OVA-specific immunoglobulin E, mast cell protease and histamine in the serum of sensitized mice and the proportion of dendritic cells and mast cells in mouse spleen were significantly reduced; in addition, F1-ESP-3 may protect the intestinal barrier and further improve the intestinal microenvironment of food-allergic mice by regulating the abundance of Bacteroidetes and Firmicutes. F1-ESP-3 can further improve the intestinal microenvironment of food-allergic mice by upregulating the levels of Lachnospiraceae, and may affect the signal pathways such as NOD-like receptor, MAPK, I kappa B and antigen processing and presentation.

Green tea extract suppresses airway inflammation via oxidative stress-driven MAPKs/MMP-9 signaling in asthmatic mice and human airway epithelial cells.

Introduction: The anti-inflammatory effect of green tea extract (GTE) has been confirmed in asthmatic mice, however, the pharmacological mechanism is not fully elucidated. Methods: To investigate the therapeutic efficacy of GTE in asthma and identify specific pathways, murine model of allergic asthma was established by ovalbumin (OVA) sensitization and the challenge for 4 weeks, with oral treatment using GTE and dexamethasone (DEX). Inflammatory cell counts, cytokines, OVA-specific IgE, airway hyperreactivity, and antioxidant markers in the lung were evaluated. Also, pulmonary histopathological analysis and western blotting were performed. In vitro, we established the model by stimulating the human airway epithelial cell line NCI-H292 using lipopolysaccharide, and treating with GTE and mitogen-activated protein kinases (MAPKs) inhibitors. Results: The GTE100 and GTE400 groups showed a decrease in airway hyperresponsiveness and the number of inflammatory cells in the bronchoalveolar lavage fluid (BALF) compared to the OVA group. GTE treatment also reduced interleukin (IL)-13, IL-5, and IL-4 levels in the BALF, and OVA-specific immunoglobulin E levels in the serum compared to those in the OVA group. GTE treatment decreased OVA-induced mucus secretion and airway inflammation. In addition, GTE suppressed the oxidative stress, and phosphorylation of MAPKs, which generally occurs after exposure to OVA. GTE administration also reduced matrix metalloproteinase-9 activity and protein levels. Conclusion: GTE effectively inhibited asthmatic respiratory inflammation and mucus hyperproduction induced by OVA inhalation. These results suggest that GTE has the potential to be used for the treatment of asthma.

Probiotic-derived amphiphilic exopolysaccharide self-assembling adjuvant delivery platform for enhancing immune responses.

Enhancing immune response activation through the synergy of effective antigen delivery and immune enhancement using natural, biodegradable materials with immune-adjuvant capabilities is challenging. Here, we present NAPSL.p that can activate the Toll-like receptor 4 (TLR4) pathway, an amphiphilic exopolysaccharide, as a potential self-assembly adjuvant delivery platform. Its molecular structure and unique properties exhibited remarkable self-assembly, forming a homogeneous nanovaccine with ovalbumin (OVA) as the model antigen. When used as an adjuvant, NAPSL.p significantly increased OVA uptake by dendritic cells. In vivo imaging revealed prolonged pharmacokinetics of NAPSL. p-delivered OVA compared to OVA alone. Notably, NAPSL.p induced elevated levels of specific serum IgG and isotype titers, enhancing rejection of B16-OVA melanoma xenografts in vaccinated mice. Additionally, NAPSL.p formulation improved therapeutic effects, inhibiting tumor growth, and increasing animal survival rates. The nanovaccine elicited CD4+ and CD8+ T cell-based immune responses, demonstrating the potential for melanoma prevention. Furthermore, NAPSL.p-based vaccination showed stronger protective effects against influenza compared to Al (OH)3 adjuvant. Our findings suggest NAPSL.p as a promising, natural self-adjuvanting delivery platform to enhance vaccine design across applications.