Search Results (122)

This study aimed to investigate the anti-allergic potential of the ethyl acetate fraction (EtOAc) from Phyllanthus amarus using an ovalbumin (OVA)-induced allergic mouse model and in vitro RBL-2H3 mast cell assays. The EtOAc fraction was characterized by high total phenolic and flavonoid contents, reaching 261 ± 18 mg GAE/g EtOAc fraction and 86 ± 7 mg QE/g EtOAc fraction, respectively. It was found that EtOAc fraction significantly reduced histamine release up to 43.3% and suppressed reactive oxygen species (ROS) production from FcɛRI-mediated mast cell activation at a concentration treatment of 200 µg/mL. Furthermore, EtOAc fraction decreased interleukin-4 (IL-4) and tumor necrosis factor-alpha (TNF-α) release up to 94.2 pg/mL and 195.6 pg/mL, respectively. In the OVA-induced allergic mouse model, EtOAc fraction treatment markedly lowered sneezing frequency and serum IgE and histamine levels by approximately 50% at a dose treatment of 50 mg/kg. In addition, histopathological analysis revealed that the EtOAc fraction significantly alleviated inflammatory cell infiltration, particularly eosinophils, in lung tissue. Accordingly, the results highlight the potential of EtOAc fraction from P. amarus as a natural candidate for managing allergic diseases. Full article

This study concurrently addressed the separation method for carbon dots derived from Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (GRRPM) and the in vitro evaluation of their anti-allergic biological activity. Glycyrrhizae Radix et Rhizoma Praeparata cum Melle Carbon Dots (GRRPM-CDs) were prepared via decoction followed by dialysis, and their properties were characterized using High-Performance Liquid Chromatography (HPLC) and nanomaterial techniques. Anti-allergic activity was evaluated using a C48/80-induced RBL-2H3 mast cell degranulation model. Safety and efficacy were assessed using the CCK-8 assay, direct intervention, and drug-containing serum methods. The release of β-hexosaminidase (β-hex), histamine (HIS), interleukin-4 (IL-4), and tumor necrosis factor-α (TNF-α) was measured by ELISA, and key proteins in the MAPK signaling pathway were analyzed by Western blot. GRRPM-CDs inhibited mast cell degranulation and the release of allergic and inflammatory mediators in a dose-dependent manner. They also significantly downregulated the phosphorylation levels of the JNK, ERK, and p38 proteins in the MAPK signaling pathway. GRRPM-CDs exhibit significant anti-allergic activity, likely via suppression of the MAPK pathway. These findings provide new insights into the bioactive components of processed Glycyrrhiza and suggest potential avenues for developing novel therapies for allergic diseases. Full article

Fish allergy, mainly caused by Parvalbumin (PV), is a worldwide health issue with few effective mitigation options. This study investigated Maillard conjugation using chitosan (CS) and various saccharides to modify the structural, functional, and allergenic properties of turbot (Scophthalmus maximus) PV. Structural analyses, including SDS-PAGE, Western blotting, FTIR spectroscopy, and Circular dichroism, confirmed successful conjugation and significant changes in secondary structure, including decreases in α-helical content and increases in β-sheet and random-coil fractions. Glycation significantly boosted antioxidant activity, with total phenolic content (TPC) increasing up to 10.3 times and DPPH radical scavenging reaching 74.5% in the CS–xylose–PV conjugate (CXTPV). Indirect ELISA revealed notable (p < 0.05), sugar-dependent reductions in IgE-binding capacity, with reductions of up to approximately 72% for CXTPV. RBL-2H3 cell assays showed decreased β-hexosaminidase release (about 75% reduction), lowered IL-6 secretion, and strong inhibition of IL-4 production, indicating reduced allergenic potential and immune regulation. CXTPV demonstrated the best overall performance. These findings suggest that CS–saccharide Maillard conjugation is an effective approach for creating hypoallergenic marine ingredients with improved bioactive properties. Full article

Natural compounds have experienced increasing clinical application, but their association with rapid-onset anaphylactoid reactions (ARs) present a significant challenge to their safe use. These ARs, clinically resembling Type I hypersensitivity, are non-IgE-mediated and involve direct mast cell activation, primarily through the human Mas-related G protein-coupled receptor X2 (MRGPRX2). We computationally screened a natural compound library for MRGPRX2 activation. A human MRGPRX2-expressing cell model was established. Cell viability assays (0–80 μM) were performed to determine appropriate drug concentrations. Compared to the controls, Baohuoside I (10 μM), along with Kaempferol-3-O-rutinoside, Epigallocatechin gallate (EGCG), Isochlorogenic Acid B, Baicalin, Andrographolide, Isorhamnetin, and Dehydroandrographolide (all at 20 μM), significantly increased intracellular calcium flux (p < 0.05) and boosted tryptase and β-hexosaminidase secretion (ELISA) (p < 0.05) in mast cells. Furthermore, the degranulation induced by these compounds was inhibited by the MRGPRX2 inhibitor Z3578 at 20 μM. Neutral red staining was employed to observe cellular morphological changes. Specific compounds capable of mediating ARs through MRGPRX2 activation on mast cells were identified. This contributes to safer and more effective drug use by elucidating the potential triggers of ARs. Full article

Background: Vasicine (Vas) is a quinazoline alkaloid derived from Adhatoda vasica Nees, which has good anti-allergic asthma and anti-inflammatory effects. However, its specific functional mechanism on allergic asthma is unclear. This study aims to investigate the protective effect of Vas on allergic asthma and its underlying mechanisms. Methods: Initially, the therapeutic effects of Vas were assessed in ovalbumin-sensitized BALB/c mice using airway hyperresponsiveness (AHR), histopathological examinations, immunohistochemistry, and enzyme-linked immunosorbent assays (ELISA). Subsequently, a non-targeted metabolomic analysis was performed to examine the influence of Vas on lung metabolites, while molecular docking was utilized to clarify the mechanisms by which Vas intervenes in allergic asthma. Lastly, RBL-2H3 cells were employed in vitro to validate the metabolomic findings by measuring intracellular Ca²⁺ concentrations, in addition to conducting ELISA and Western blot analyses. Results: In vivo, Vas alleviates AHR in mice with allergic asthma, enhances histopathological conditions, and reduces inflammatory factors. Non-targeted metabolomics analyses indicate that the primary pathway implicated in its intervention in allergic asthma may be the FcεRI pathway. Furthermore, molecular docking techniques were utilized to evaluate the binding affinity between Vas and proteins associated with this pathway. In vitro, Vas effectively inhibits degranulation in RBL-2H3 cells and diminishes the release of inflammatory factors by modulating the FcεRI/Lyn + Syk/MAPK pathway. Conclusions: These findings indicate that Vas may effectively alleviate allergic asthma by reducing inflammatory responses, decreasing AHR, and improving histopathological features. Furthermore, Vas seems to inhibit mast cell degranulation and modulate the FcεRI/Lyn + Syk/MAPK pathway. Full article

Respiratory and food allergy conditions are increasing internationally and the most commonly used drugs in these conditions are antihistamines, products that can interfere as histamine receptor antagonists. In accordance with the need to test new principals capable of developing fewer side effects, we preliminarily studied the therapeutic antihistamine effect in vitro and in vivo of an innovative nutraceutical blend based on Quercetin, Perilla frutescens, Boswellia serrata, Blackcurrant, Parthenium, Helichrysum, Lactobacillus acidophilus and Bifidobacterium animalis. The in vitro test demonstrated the interaction between the examined mixture and a rat leukemia cell line (RBL-2H3) widely used as a model simulating mast cells in immunological and allergological studies; this pre-clinical test demonstrated a statistically significant reduction in cell histamine degranulation (about 30%). The in vivo test demonstrated instead that the mixture interferes up to 30% in the development of histamine wheal. In addition, during the in vitro test, we also tested the effect of the mixture on allergic inflammation, so we evaluated the interference of the mixture on TNF alpha levels, determining a reduction in tested concentrations of about 13%. Full article

This study aimed to compare the therapeutic effects of fresh (CMF) and dried (CMD) Centipeda minima against allergic rhinitis (AR), elucidate their underlying molecular mechanisms, and identify the bioactive compounds responsible for their immunomodulatory actions. An ovalbumin-induced AR mouse model was treated with CMF or CMD extracts, followed by evaluation of nasal symptoms, serum biomarkers (IgE, histamine, cytokines), and nasal mucosa histopathology. Transcriptomics and widely targeted metabolomics were integrated with network pharmacology to identify differentially expressed genes and bioactive components, which were further validated in RAW264.7 and RBL-2H3 cells. CMF and CMD exhibited distinct anti-AR mechanisms: CMF predominantly suppressed Th2 responses (reducing IgE, IL-6, and histamine while elevating IL-10), whereas CMD enhanced Th1 activity (increasing IFN-γ). Metabolomic analysis revealed CMF was rich in amino acids while CMD contained higher flavonoids, with neocnidilide and 6-gingerol identified as key bioactive compounds that modulated TNF-α, IL-6, and IL-10 via NF-κB and JAK-STAT pathways. These findings demonstrate that CMF and CMD exert complementary anti-inflammatory effects through Th2 inhibition and Th1 activation, respectively, providing a molecular basis for the traditional use of Centipeda minima and highlighting its bioactive compounds as potential therapeutics for inflammatory diseases. Full article

Atopic dermatitis (AD) is a chronic inflammatory disorder with immune imbalance, including elevated IgE levels and mast cell activation mediated by Th2 cytokines, leading to allergic inflammation and impaired skin barrier function. Current treatment limitations highlight the need for safer and more effective AD alternatives. We aimed to evaluate the therapeutic effects of multi-strain probiotics, BCL-2 (comprising Lactiplantibacillus plantarum LRCC5264 and Bifidobacterium longum RAPO), in alleviating AD clinical signs and elucidate its underlying immunomodulatory mechanisms. In vitro, BCL-2 treatment significantly reduced IL-4 secretion in RBL-2H3 cells, with higher inhibitory effects than single-strain treatment. In vivo, BCL-2 (10⁶–10⁸ CFU/day) was orally administered for 28 days to AD-induced Nc/Nga mice. BCL-2 treatment improved the clinical signs and histopathological features of AD, including epidermal hypertrophy, hyperkeratosis, and mast cell infiltration (p < 0.05). It also reduced neutrophil and eosinophil counts and modulated cytokine and chemokine profiles, notably decreasing IL-17, IL-5, IL-6, TNF-α, IL-1β, TARC, and eotaxin, while increasing IL-10, IFN-γ, and IL-12 (p < 0.05). Among the tested concentrations, 10⁷ CFU exhibited the most effective immune modulation with no adverse effects on body weight. These findings demonstrate the therapeutic potential of BCL-2 in AD; however, further studies are required to validate its clinical relevance. Full article

Background/Objectives: Allergens can trigger severe immune responses in hypersensitive individuals, with mast cells releasing inflammatory mediators via IgE-FcɛRI signaling. Spleen tyrosine kinase (Syk) is a key regulator in this pathway, making it a promising therapeutic target. Natural modulators of Syk-mediated mast cell activation remain underexplored. This study investigated the anti-allergic effects of a 70% ethanol extract of Salvia miltiorrhiza (SME) using in vitro and in vivo models. Methods: SME was evaluated using IgE-sensitized RBL-2H3 cells, a passive cutaneous anaphylaxis model, and a DNCB-induced atopic dermatitis-like mouse model. Allergic responses were assessed via degranulation assays, histopathology, serum IgE levels, and the spleen index. Results: SME significantly inhibited mast cell degranulation by 44.4 ± 1.6% in RBL-2H3 cells at 100 µg/mL following 30 min of treatment compared to the untreated control. Western blot analysis demonstrated dose-dependent suppression of protein kinase B (PKB, also known as AKT), c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and spleen tyrosine kinase (Syk) phosphorylation, indicating inhibition of key allergic signaling pathways. In an IgE/Ag-induced passive cutaneous anaphylaxis model in ICR mice, SME (100 mg/kg, orally) significantly attenuated vascular permeability, as evidenced by a 20.6 ± 9.7% reduction in Evans blue extravasation relative to the Ag-treated group. In a 1-chloro-2,4-dinitrobenzene (DNCB)-induced atopic dermatitis (AD)-like model, six treatments of SME significantly improved the skin condition, reduced spleen enlargement associated with allergic inflammation, and decreased serum IgE levels by 43.3 ± 11.2% compared to the DNCB group. Conclusions: These findings suggest that SME may help to alleviate allergic responses and AD by modulating key immune signaling pathways. Full article

Background/Objectives: The Wikstroemia genus has been traditionally used in Asia to treat various ailments, including parotitis, pneumonia, and pertussis. These plants contain many bioactive compounds, including flavonoids, coumarins, and lignans. This study investigates the chemical components of a MeOH extract of the aerial parts of Wikstroemia trichotoma (Thunb.) Makino and evaluates their anti-inflammatory and anti-allergic effects in vitro. Methods: Chromatographic techniques, spectroscopic analysis, and the literature were used to isolate compounds from the branches and leaves of W. trichotoma. IL-4 mRNA and β-hexosaminidase levels were assessed by performing assays on RBL-2H3 cells to evaluate anti-inflammatory and anti-allergic potential. Results: Forty-two compounds were isolated from the W. trichotoma extract, and the flavanones trichotocinol A and B were newly identified. Screening of isolated compounds showed that several significantly inhibited DNP-BSA-induced β-hexosaminidase release by 10.0–58.0% and PMA/ionomycin-induced IL-4 mRNA expression by 25.3–71.7% versus negative controls. In addition, trichotocinol A reduced IL-4 mRNA expression by 31.9%. Conclusions: The discovery of these new compounds contributes to our understanding of the bioactive properties of W. trichotoma and suggests their potential use as natural therapeutic agents for inflammatory disorders. Full article

TGF-β is a pleiotropic cytokine with both stimulatory and inhibitory effects on immune cells, depending on the microenvironmental context. It targets mast cells (MCs) in different physio-pathological conditions, such as inflammation and cancer. Besides acting as a potent chemoattractant for MCs, TGF-β regulates many other aspects of MCs’ physiology, including the secretion of many regulatory molecules. MCs secrete a variety of mediators, either pre-formed or newly synthesized, upon appropriate stimulation. CCL-2 chemokine and TNF cytokine act as potent chemoattractants for several immune cells and participate in the initiation of inflammatory responses by recruiting them to injured tissues. TGF-β regulates CCL-2 and TNF secretion in different cell types and under distinct cellular contexts. Here, we report that the treatment with TGF-β alone induces the secretion of both pre-formed and newly synthesized CCL-2 in the rat RBL-2H3 mast cells but not in mouse bone marrow-derived mast cells (BMMCs). TGF-β-induced CCL-2 secretion depends on rapid rearrangements of the actin cytoskeleton and, remarkably, on the early secretion of soluble TNF that triggers an autocrine TNF signaling. In conclusion, we found cooperation between TGF-β and TNF signaling pathways to promote the secretion of CCL-2 chemokine by MCs in a cell-context specific manner. Full article

Peanut allergies, driven by sensitization to key allergens Ara h1, Ara h2, and Ara h3, present significant health risks, particularly in food processing and consumer settings where accidental exposure is frequent. To mitigate this risk, we developed AYA22AR321, a novel aptamer with selective, high-affinity binding to these allergens (Kd values: 0.5 nM for Ara h1, 14.5 nM for Ara h2, and 6.6 nM for crude peanut extract). Functional assays using RBL-2H3 (rat basophilic leukemia cell line) cells showed that AYA22AR321 significantly reduces IgE-mediated degranulation, indicating its potential to attenuate allergic responses. To translate these findings into practical use, we formulated an allergen-neutralizing spray, FISTOQ, containing AYA22AR321, which effectively neutralized peanut allergens on peanut-butter-contaminated surfaces. Stability tests confirmed that FISTOQ, comprising eco-friendly surfactant and preservative, maintains its allergen-neutralizing efficacy over time. Comprehensive safety assessments, including immunogenicity, cytotoxicity in human PBMCs, and mutagenicity via the Ames test, demonstrated that AYA22AR321 is non-immunogenic, non-cytotoxic, and non-mutagenic. This study establishes AYA22AR321 as a promising, targeted strategy for allergen control, providing a significant advancement in allergen mitigation and food safety for high-risk environments. Full article

Background: Yupingfeng San (YPFS) is a classic formula for treating allergic rhinitis (AR), which is composed of Astragalus mongholicus Bunge (AST), Atractylodes macrocephala Koidz (AMR), and Saposhni-kovia divaricata (Turcz.) Schischk (SR) at a ratio of 3:1:1. However, the potential bioactive components of YPFS relevant to AR treatment are currently unknown. Methods: This study combined in vivo chemical profiling, network pharmacology, and experimental validation to identify the substances in YPFS that are active against AR. Results: Firstly, 98 compounds in YPFS were identified using high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS) with the assistance of Global Natural Products Social (GNPS) molecular networking. Then, 42 prototype components and 57 metabolites were detected in the plasma, urine, and feces of mice with AR. A network pharmacological analysis based on 42 in vivo prototypical components was also conducted to screen 15 key components and 10 core targets, and 6 key components were further selected through molecular docking. Finally, the four key active components (cimifugin, wogonin, formononetin, and atractylenolide I) were revealed to be the main ingredients of YPFS through validation (in vitro and in vivo). Conclusions: This is the first systematic study of the components of YPFS in AR mice, laying the foundation for elucidating the overall material basis of this formulation. This study provides rich basic data for further pharmacological and mechanistic studies on YPFS. Full article

Rocaglamide (Roc-A), a natural phytochemical isolated from Aglaia species, is known to exert anticancer effects. Allergic inflammation can enhance the tumorigenic potential of cancer cells. We hypothesized that Roc-A could regulate allergic inflammation. Roc-A prevented an antigen from increasing the hallmarks of allergic reactions in vitro. Roc-A suppressed passive cutaneous anaphylaxis (PCA) and passive systemic anaphylaxis (PSA). RNA sequencing analysis showed that Roc-A prevented the antigen from increasing the expression of IL-4 in RBL2H3 cells. Roc-A also prevented the antigen from increasing the expression of interleukin-4 receptor (IL-4R). Roc-A was found to form a hydrogen-bonding network with residues N92 and L64 of IL-4R in a molecular docking simulation. Roc-A prevented the antigen from inducing the binding of IL-4R to JAK1. Chromatin immunoprecipitation (ChIP) assays showed that C-Jun could bind to promoter sequences of IL-4 and IL-4R. Mouse recombinant IL-4 protein increased β-hexosaminidase activity, IL-4R expression, and the hallmarks of allergic inflammation in the antigen-independent manner. Mouse recombinant IL-4 protein increased the expressions of CD163 and arghinase-1 and markers of M2 macrophages, but decreased the expression of iNOS, a marker of M1 macrophages in lung macrophages. Roc-A regulated the effects of a culture medium of antigen-stimulated RBL2H3 cells on the expressions of iNOS and arginase-1 in RAW264.7 macrophages. The blocking of IL-4 or downregulation of IL-4R exerted negative effects on the hallmarks of allergic reactions in vitro. The blocking of IL-4 or downregulation of IL-4R also exerted negative effects on PCA, and the downregulation of IL-4R exerted negative effects on PSA. An miR-34a mimic exerted negative effects on allergic reactions in vitro. The downregulation of IL-4R prevented the antigen from decreasing the expression of miR-34a in RBL2H3 cells. We identified chemicals that could bind to IL-4R via molecular docking analysis. The IL-4R docking chemical 1536801 prevented the antigen from increasing β-hexosaminidase activity and the hallmarks of allergic reactions. The IL-4R docking chemical 1536801 also exerted a negative effect on PCA. TargetScan analysis predicted miR-34a as a negative regulator of IL-4R. We found that the anti-allergic effect of Roc-A and its mechanisms were associated with miR-34a. Taken together, our results show that understanding IL-4R-mediated allergic reactions can provide clues for the development of anti-allergy therapeutics. Full article

Public acceptance of genetically modified crops engineered with Bacillus thuringiensis (Bt) insecticidal protein genes (BT-GMCs), which confer resistance to various lepidopteran insect pests, is generally lacking. As a major concern over BT-GMCs is the allergenicity of insecticidal proteins, alleviating safety concerns should help increase public acceptance. In this study, three lepidopteran-specific Bt toxins, Cry1Aa, Cy1Ab, and Cry1Ac, were treated with simulated digestive fluids under various conditions. Western blotting using antiserum raised against individual segments (α-helices of domain I and β-sheets of domains II and III) of Cry1Aa showed that digestion produces a variety of polypeptides. In particular, the transmembrane α4–α5 of domain I, which may retain the ability to form pores, was the most resistant to digestion. Intact Cry1A toxins and these digests were then applied to RBL-2H3 cultured rat mast cells to determine whether the toxins directly induce histamine release. However, fluorescence microscopy revealed no specific binding of Cry1A toxins to RBL-2H3 cultured rat mast cells. In addition, neither the OPA method nor HPLC analysis detected significant histamine release from mast cells treated with Cry1A toxins and these digests. Our results provide important data supporting the safety of Cry1A toxins and potentially BT-GMCs. Full article