Astragalus Polysaccharides Attenuate Ovalbumin-Induced Allergic Rhinitis in Rats by Inhibiting NLRP3 Inflammasome Activation and NOD2-Mediated NF-κB Activation

Astragalus membranaceus, Nigella sativa, and Perilla frutescens as Immunomodulators-Molecular Mechanisms and Clinical Effectiveness in Allergic Diseases

Plants are the source of numerous remedies in modern medicine, and some of them have been studied due to their potential immunomodulatory activity. Astragalus membranaceus Fisch. ex Bunge (A. membranaceus), Nigella sativa L. (N. sativa), and Perilla frutescens (L.) Britton (P. frutescens) are plant species used in traditional medicine for the treatment of various diseases. Their potential to act as immunomodulatory, anti-inflammatory, and anti-allergic agents makes them interesting for investigating their clinical potential in alleviating the symptoms of allergic diseases. Allergy affects a large number of people; according to some sources more than 30% of the world population suffer from some type of allergic reaction, with pollen allergy as the most common type. Treatment is usually pharmacological and may not be completely effective or have side effects. Thus, we are seeking traditional medicine, mostly medicinal plants, with promising potential for alleviating allergy symptoms. A literature overview was conducted employing databases such as Scopus, PubMed, Web of Science, Springer, and Google Scholar. This manuscript summarizes recent in vivo preclinical and clinical studies on three species with immunomodulatory activity, provides a comparison of their anti-allergic effects, and underlines the potential of their application in clinical practice. The obtained results confirmed their efficacy in the in vivo and clinical studies, but also emphasize the problem of phytochemical characterization of the species and difference between tested doses. More clinical trials with standardized protocols (defined active molecules, dosage, side effects) are required to obtain safe and effective herbal drugs.

Network pharmacology analysis of the Huangqi-Gancao herb pair reveals quercetin as a therapeutics for allergic rhinitis via the RELA-regulated IFNG/IRF1 axis response

Despite the complexity of allergic rhinitis (AR) pathogenesis, no FDA-approved drug has been developed to achieve optimal therapeutic effects. The present study explored the efficacy and mechanism of Huangqi (Hedysarum Multijugum Maxim)-Gancao (Glycyrrhizae Radix et Rhizoma or licorice) herb pair in treating AR by network pharmacology and experimental approaches. The bioactive ingredients of Huangqi and Gancao were identified and used to predict the targets of these herbs in AR and generate the pharmacological network. Ovalbumin (OVA)-induced AR mouse model was established to assess the anti-AR effect of the Huangqi decoction (HQD) prepared based on both herbs. We identified 90 active ingredients of the Huangqi-Gancao pair, targeting 69 AR-related genes. Quercetin (QUE) was identified as the hub ingredient of this pair, with 57 targets in AR. The protein-protein interaction (PPI) network analysis and molecular docking revealed IL1B, TNF, STAT1, IL6, PTGS2, RELA, IL2, NFKBIA, IFNG, IL10, IL1A, IRF1, EGFR, and CXCL10 as important targets of QUE in AR treatment. Experimentally, QUE or HQD significantly alleviated the AR-induced histopathological changes, AR symptoms, and IgE level and counteracted AR-induced expression changes of IFNG, IRF1, RELA, and NFKBIA. These effects were promoted by the NF-kB inhibitor helenalin, indicating that HQD and QUE counteracted AR in mice by regulating the IFNG/IRF1 signaling via the NF-κB pathway in AR mice. These findings shed light on the efficacy of the constituents of Huangqi-Gancao pair, their potential targets, and the molecular mechanisms of HQD in treating AR, which could advance the development of tailored therapeutic interventions for this disorder.

Astragalus polysaccharide alleviates IL-13-induced oxidative stress injury in nasal epithelial cells by inhibiting WTAP-mediated FBXW7 m6A modification

Background

Allergic rhinitis (AR) a common and complicated upper airway disease mediated by specific IgE antibodies. Our study aims to explore the pharmacological effects of astragalus polysaccharide (APS) on AR and elucidate the mechanisms involved.

Methods

RT-qPCR and Western blotting were used to analyze mRNA and protein expression. Interleukin (IL)-13-treated human nasal epithelial cells (hNECs) was employed as the AR cell model. Cell apoptosis and viability were evaluated by TUNEL staining and MTT assay, respectively. ROS level was examined by the DCFH-DA probe. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels were measured by the corresponding kits. FBXW7 m6A modification level was assessed by MeRIP assay.

Methods

Our results showed that APS treatment reduced cell apoptosis, ROS, and MDA levels while increasing SOD, CAT, and GSH-Px levels in IL-13-treated hNECs by activating the Nrf2/HO-1 pathway. Moreover, APS alleviated IL-13-induced oxidative stress injury in hNECs by downregulating WTAP. In addition, WTAP knockdown increased FBXW7 mRNA stability by regulating FBXW7 mRNA m6A modification. It also turned out that APS alleviated IL-13-induced oxidative stress injury in hNECs through the WTAP/FBXW7 axis.

Conclusions

Taken together, APS inhibited WTAP-mediated FBXW7 m6A modification to alleviate IL-13-induced oxidative stress injury in hNECs.

Unraveling the role of NLRP3 inflammasome in allergic inflammation: implications for novel therapies

Allergic diseases like asthma, allergic rhinitis and dermatitis pose a significant global health burden, driving the search for novel therapies. The NLRP3 inflammasome, a key component of the innate immune system, is implicated in various inflammatory diseases. Upon exposure to allergens, NLRP3 undergoes a two-step activation process (priming and assembly) to form active inflammasomes. These inflammasomes trigger caspase-1 activation, leading to the cleavage of pro-inflammatory cytokines (IL-1β and IL-18) and GSDMD. This process induces pyroptosis and amplifies inflammation. Recent studies in humans and mice strongly suggest a link between the NLRP3 inflammasome, IL-1β, and IL-18, and the development of allergic diseases. However, further research is needed to fully understand NLRP3's specific mechanisms in allergies. This review aims to summarize the latest advances in NLRP3 activation and regulation. We will discuss small molecule drugs and natural products targeting NLRP3 as potential therapeutic strategies for allergic diseases.

Boswellic acid and apigenin alleviate methotrexate-provoked renal and hippocampal alterations in rats: Targeting autophagy, NOD-2/NF-κB/NLRP3, and connexin-43

The neuronal and renal deteriorations observed in patients exposed to methotrexate (MTX) therapy highlight the need for medical interventions to counteract these complications. Boswellic acid (BA) and apigenin (APG) are natural phytochemicals with prominent neuronal and renal protective impacts in various ailments. However, their impacts on MTX-provoked renal and hippocampal toxicity have not been reported. Thus, the present work is tailored to clarify the ability of BA and APG to counteract MTX-provoked hippocampal and renal toxicity. BA (250 mg/kg) or APG (20 mg/kg) were administered orally in rats once a day for 10 days, while MTX (20 mg/kg, i.p.) was administered once on the sixth day of the study. At the histopathological level, BA and APG attenuated MTX-provoked renal and hippocampal aberrations. They also inhibited astrocyte activation, as proven by the inhibition of glial fibrillary acidic protein (GFAP). These impacts were partially mediated via the activation of autophagy flux, as proven by the increased expression of beclin1, LC3-II, and the curbing of p62 protein, alongside the regulation of the p-AMPK/mTOR nexus. In addition, BA and APG displayed anti-inflammatory features as verified by the damping of NOD-2 and p-NF-κB p65 to reduce TNF-α, IL-6, and NLRP3/IL-1β cue. These promising effects were accompanied with a notable reduction in one of the gap junction proteins, connexin-43 (Conx-43). These positive impacts endorse BA and APG as adjuvant modulators to control MTX-driven hippocampal and nephrotoxicity.

Understanding the role of NLRP3-mediated pyroptosis in allergic rhinitis: A review

Allergic rhinitis (AR) is a chronic, inflammatory disease of the nasal mucosa, caused by the immunoglobulin E-mediated immune response. The annual incidence rate of AR is on the rise, exerting a significant impact on individuals' physical and mental wellbeing. The treatment effect in some patients is still not ideal, as the pathogenesis of AR is complex and diverse. Recent studies have shown that NLRP3 inflammasome-mediated pyroptosis is widely involved in the occurrence and development of AR through various pathways. This article reviews the mechanism of pyroptosis and its research progress in the field of AR, and puts forward possible therapeutic targets to offer innovative approaches for its management.

Beneficial Effects of Astragalus membranaceus (Fisch.) Bunge Extract in Controlling Inflammatory Response and Preventing Asthma Features

Astragalus membranaceus (Fisch.) Bunge root is used as herbal medicine for its immunomodulating activities in Chinese medicine. Recently, beneficial properties of A. membranaceus on allergic diseases have been proposed. Here we investigated the role of a commercial extract of A. membranaceus, standardized to 16% polysaccharides, in regulating the immune-inflammatory response in vitro and in vivo and its therapeutic application in asthma. A. membranaceus extract inhibited prostaglandin E₂ and leukotriene C₄ production in stimulated J774 and peritoneal macrophages, respectively. The extract also reduced interlukin-1β, tumor necrosis factor-α, and nitrite production, affecting inducible nitric oxide synthase expression. In vivo experiments confirmed the anti-inflammatory properties of A. membranaceus, as evident by a reduction in zymosan-induced peritoneal cellular infiltration and pro-inflammatory mediator production. The efficacy of A. membranaceus extract in modulating the immune response was confirmed in a model of allergic airway inflammation. Extracts improve lung function by inhibiting airway hyperresponsiveness, airway remodeling, and fibrosis. Its anti-asthmatic effects were further sustained by inhibition of the sensitization process, as indicated by a reduction of ovalbumin-induced IgE levels and the mounting of a Th2 immune response. In conclusion, our data demonstrate the anti-inflammatory properties of the commercial extract of A. membranaceus and its beneficial effects on asthma feature development.

Mechanism of Kruppel-Like Factor 4 in Pyroptosis of Nasal Mucosal Epithelial Cells in Mice With Allergic Rhinitis

BACKGROUND

Allergic rhinitis (AR) is a chronic nasal inflammation, characterized by nasal epithelial dysfunction. Gene therapy targeting transcription factors is a promising strategy for quenching allergic inflammation, including AR.

OBJECTIVE

This study sought to probe the mechanism of Kruppel-like factor 4 (KLF4) in pyroptosis of nasal mucosal epithelial cells (NEpCs) in AR mice and provide targets for AR treatment.

METHODS

AR mouse models were established using sensitization with ovalbumin, followed by injection with short hairpin RNA KLF4 (sh-KLF4). AR symptoms were assessed by the times of sneezing and nose rubbing, hematoxylin-eosin, and periodic acid-Schiff staining. Levels of KLF4, nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3), cleaved caspase-1, and N-terminal domain (GSDMD-N) in nasal mucosal tissues were determined by Western blot assay, and levels of interleukin (IL)-1β and IL-18 in nasal lavage fluid were determined by enzyme-linked immunosorbent assay. The binding of KLF4 to the NLRP3 promoter was verified using chromatin immunoprecipitation and dual-luciferase assays. The functional rescue experiment was performed with oe-NLRP3 and sh-KLF4 in AR mice.

RESULTS

KLF4 was upregulated in nasal mucosal tissues of AR mice. KLF4 inhibition reduced the times of sneezing and nose rubbing, inflammatory cell infiltration, and goblet cell hyperplasia in nasal mucosal tissues, and levels of NLRP3, cleaved caspase-1, GSDMD-N, IL-1β, and IL-18. KLF4 was enriched on the NLRP3 promoter and improved NLRP3 expression. NLRP3 overexpression reversed the inhibition of sh-KLF4 on pyroptosis of NEpCs in AR mice.

CONCLUSION

KLF4 bound to the NLRP3 promoter and promoted pyroptosis of NEpCs in AR mice via activating NLRP3.

Implications of fractalkine on glial function, ablation and glial proteins/receptors/markers—understanding its therapeutic usefulness in neurological settings: a narrative review

Background

Fractalkine (CX3CL1) is a chemokine predominantly released by neurons. As a signaling molecule, CX3CL1 facilitates talk between neurons and glia. CX3CL1 is considered as a potential target which could alleviate neuroinflammation. However, certain controversial results and ambiguous role of CX3CL1 make it inexorable to decipher the overall effects of CX3CL1 on the physiopathology of glial cells.

Main body of the abstract

Implications of cross-talk between CX3CL1 and different glial proteins/receptors/markers will give a bird eye view of the therapeutic significance of CX3CL1. Keeping with the need, this review identifies the effects of CX3CL1 on glial physiopathology, glial ablation, and gives a wide coverage on the effects of CX3CL1 on certain glial proteins/receptors/markers.

Short conclusion

Pinpoint prediction of the therapeutic effect of CX3CL1 on neuroinflammation needs further research. This is owing to certain obscure roles and implications of CX3CL1 on different glial proteins/receptors/markers, which are crucial under neurological settings. Further challenges are imposed due to the dichotomous roles played by CX3CL1. The age-old chemokine shows many newer scopes of research in near future. Thus, overall assessment of the effect of CX3CL1 becomes crucial prior to its administration in neuroinflammation.

Astragalus Polysaccharides Affect Glioblastoma Cells Through Targeting miR-34a-5p

This study discussed Astragalus Polysaccharides (APS)’s effect on the cytobiology of glioma. U87 glioma cells were assigned into control group (U87 cells), miR-34a-5p mimic group (transfected with miR-34a-5p mimic), and APS group (treated with 10 μM APS) followed by analysis of miR-34a-5p level, cell proliferation and invasion, Caspase3 and SOD activity as well as E-cadherin, Vimentin and survivn expression. APS treatment significantly upregulated miR-34a-5p expression, inhibits cell proliferation and invasion, and promoted cell apoptosis. In addition, APS also significantly upregulated E-cadherin, downregulated Vimentin and survivn level in glioma cells as well as inhibited ROS generation and increased SOD activity. In conclusion, the level of miR-34a-5a in glioma cells is up-regulated by APS so as to restrain the biological behaviors of glioma cells, indicating that it might be used as novel agent for the treatment of glioma.

Astragalus polysaccharide: a review of its immunomodulatory effect

The Astragalus polysaccharide is an important bioactive component derived from the dry root of Astragalus membranaceus. This review aims to provide a comprehensive overview of the research progress on the immunomodulatory effect of Astragalus polysaccharide and provide valuable reference information. We review the immunomodulatory effect of Astragalus polysaccharide on central and peripheral immune organs, including bone marrow, thymus, lymph nodes, spleen, and mucosal tissues. Furthermore, the immunomodulatory effect of Astragalus polysaccharide on a variety of immune cells is summarized. Studies have shown that Astragalus polysaccharide can promote the activities of macrophages, natural killer cells, dendritic cells, T lymphocytes, B lymphocytes and microglia and induce the expression of a variety of cytokines and chemokines. The immunomodulatory effect of Astragalus polysaccharide makes it promising for the treatment of many diseases, including cancer, infection, type 1 diabetes, asthma, and autoimmune disease. Among them, the anticancer effect is the most prominent. In short, Astragalus polysaccharide is a valuable immunomodulatory medicine, but further high-quality studies are warranted to corroborate its clinical efficacy.

Astragalus Polysaccharide Relieves Inflammatory Responses in Guinea Pigs with Allergic Rhinitis via Ameliorating NF-kB-Mediated Treg/Th17 Imbalance

BACKGROUND

Allergic rhinitis (AR) is regarded as a prevalent and non-infectious inflammation in nasal mucosa, and astragalus polysaccharide (APS) could mitigate inflammation.

OBJECTIVES

Herein, this study probed the specific mechanism of APS in inflammatory responses in AR.

METHODS

Firstly, AR guinea pig models were established through the stimulation and sensitization of ovalbumin (OVA) and received APS treatment. Changes in nasal symptoms were assessed through counting the sneezing and rubbing times of guinea pigs. The change patterns of OVA-specific immunoglobulin-E (OVA-sIgE), OVA-specific immunoglobulin-G1 (OVA-sIgG1), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 in guinea pig serum were identified. Meanwhile, the levels of IL-17, transforming growth factor (TGF)-β, IL-10, and forkhead box protein P3 (Foxp3) in the guinea pig tissues or serum were examined, and CD25⁺Foxp3⁺Treg or CD4⁺IL17⁺Th17 cell proportion was detected. Afterwards, nuclear factor-kappa B (NF-kB) expression in guinea pig nasal mucosa tissues were examined. Rescue experiments were designed to probe the role of NF-kB overexpression in inflammatory responses and Treg/Th17 imbalance in AR guinea pigs.

RESULTS

APS treatment reduced sneezing and rubbing times of AR guinea pigs and suppressed OVA-sIgE, OVA-sIgG1, TNF-α, and IL-6 levels in guinea pig serum, and meanwhile, increased CD25⁺Foxp3⁺Treg cell proportion while reduced CD4⁺IL17⁺Th17 cell proportion in AR guinea pig serum or tissues, in a dose-dependent manner. NF-kB was highly-expressed in AR guinea pigs and down-regulated after APS treatment. NF-kB overexpression facilitated inflammatory responses and Treg/Th17 imbalance in AR.

CONCLUSION

APS reduced Treg/Th17 imbalance via suppressing NF-kB expression, thereby ameliorating inflammatory responses in AR.

Modulatory Properties of Food and Nutraceutical Components Targeting NLRP3 Inflammasome Activation

Inflammasomes are key intracellular multimeric proteins able to initiate the cellular inflammatory signaling pathway. NLRP3 inflammasome represents one of the main protein complexes involved in the development of inflammatory events, and its activity has been largely demonstrated to be connected with inflammatory or autoinflammatory disorders, including diabetes, gouty arthritis, liver fibrosis, Alzheimer’s disease, respiratory syndromes, atherosclerosis, and cancer initiation. In recent years, it has been demonstrated how dietary intake and nutritional status represent important environmental elements that can modulate metabolic inflammation, since food matrices are an important source of several bioactive compounds. In this review, an updated status of knowledge regarding food bioactive compounds as NLRP3 inflammasome modulators is discussed. Several chemical classes, namely polyphenols, organosulfurs, terpenes, fatty acids, proteins, amino acids, saponins, sterols, polysaccharides, carotenoids, vitamins, and probiotics, have been shown to possess NLRP3 inflammasome-modulating activity through in vitro and in vivo assays, mainly demonstrating an anti-NLRP3 inflammasome activity. Plant foods are particularly rich in important bioactive compounds, each of them can have different effects on the pathway of inflammatory response, confirming the importance of the nutritional pattern (food model) as a whole rather than any single nutrient or functional compound.

Ajwain oil attenuates allergic response of ovalbumin-induced allergic rhinitis via alteration of inflammatory, oxidative stress, and Th1/Th2 responses

BACKGROUND

Allergic rhinitis (AR) is an immune inflammatory-related disorder that affects the nasal mucosa. Free radicals play a crucial role in the expansion of allergic reaction and the researcher used the antioxidant therapy to treat the disease. Trachyspermum ammi L. (Ajwain oil) is popular traditional medicine. It has been proved their potential effect on various diseases. Ajwain oil showed anti-tumor, antioxidant, antidiabetic, anti-inflammatory, and anti-bacterial properties. Yet, the anti-allergic effect of Ajwain oil is still not explored. In this experimental study, an ovalbumin (OVX)-induced AR model was used to scrutinize the anti-allergic, antioxidant and anti-inflammatory effects of Ajwain oil.

MATERIALS AND METHODS

OVX was used to establish the AR model (sensitization days 1, 8, and 15) and given the oral treatment of Ajwain oil and Montelukast for 13 days. The spleen, lungs, and body weight were estimated. Sneezing, nasal discharge and rubbing are also estimated. Immunoglobin-E (IgE), histamine, malondialdehyde (MDA), superoxide dismutase (SOD), heme oxygenase-1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nrf2), and inflammatory cytokines were scrutinized.

RESULTS

Ajwain oil significantly (p < .001) suppressed sneezing, nasal discharge and nasal rubbing along with increasing the spleen, lung and body weight. Ajwain oil significantly (p < .001) decreased the level of IgE, histamine, MDA, Nrf2, HO-1, and increased the level of SOD. Ajwain oil significantly (p < .001) suppressed the number of eosinophils, neutrophils, macrophages, and epithelial cells. Ajwain oil significantly prevented the activation of the NF-κBp65 and STAT3 signaling pathways that led to enhancing the synthesis of anti-inflammatory cytokines and reducing the inflammatory, allergen-specific type 2T helper cells (Th2), Th17 cytokines.

CONCLUSION

The obtained data suggests that Ajwain oil has a promising anti-allergic against allergic rhinitis in mice via anti-allergic, antioxidant, and anti-inflammatory effects.

PRACTICAL APPLICATIONS

Allergic rhinitis is a serious life-threatening disease. Inflammatory reaction plays an important role in the expansion of AR diseases. Ajwain oil considerably increased the spleen weight and reduced lung weight. Ajwain oil suppressed the nasal rubbing, sneezing, and nasal discharge. Ajwain oil considerably suppressed the immunoglobin and inflammatory cytokines. The result suggests that Ajwain oil having the potential effect against the allergic rhinitis.

Anti-Inflammation and Protective Effects of Anethum graveolens L. (Dill Seeds) on Esophageal Mucosa Damages in Reflux Esophagitis-Induced Rats

Anethum graveolens L. (dill seeds) are important medicinal and functional foods in Europe and central and south Asia, often used as a seasoning in daily diets. Anethum graveolens L. seeds (AGS) are used to treat indigestion and have shown physiological activities such as those against hypoglycemia and gastroesophageal disease. This study explored the protective effects of AGS extract on mucosal damages and inflammation in reflux esophagitis rats. AGS inhibited cellular inflammation including NO production and the expression of inflammatory proteins (iNOS and COX2 etc.), cytokines (IL-1β and TNF-α) and nuclear transfer factor related to NF-κB signaling caused by LPS stimulation in vitro. Furthermore, reflux esophagitis-induced rats were used to observe the anti-inflammatory effect of AGS. Tissue staining and inflammation-related protein expression of rats with acute reflux esophagitis indicated that AGS improved this inflammatory response, such as COX-2 and TNF-α in mucosa. In conclusion, AGS have good physiological activity and the possibility of being used as a medicinal food and a functional resource for the prevention and therapy of gastroesophageal diseases.