Quercetin with the potential effect on allergic diseases

Co-expression of α-L-rhamnosidase and β-glucosidase in Aspergillus niger and its application in enzymatic production of quercetin

Quercetin (3,3',4',5,7-pentahydroxy flavonoid) is a bioactive flavonoid with significant medicinal properties. Similarly, Rutin (quercetin-3-O-rutinoside or 3',4',5,7-tetrahydroxy-flavone-3-rutinoside) is widely recognized flavonoid, and is converted to quercetin by α-L-rhamnosidase and β-D-glucosidase. In this study, engineered Aspergillus niger co-expressing α-L-rhamnosidase and β-glucosidase was successfully constructed, and engineered strain Rha1-BGL8 was obtained by enzyme activity assay. When submerged fermentation after 120 h in 5 L of fermenter, the α-L-rhamnosidase activity was 36.90 U/mL and β-glucosidase activity was 61.02 U/mL. The fermented complex enzyme solution was employed for the hydrolysis of rutin to quercetin, and the yield of quercetin reached 95.31 % after 48 h, molecular structure of quercetin was verified by highly specific chromatographic methods. This study lays a technical foundation for the potential industrial application of enzyme-catalyzed conversion of rutin to quercetin.

Therapeutic Potential of Herbal Compounds in Curing Dysmenorrhea Naturally: A Review

Dysmenorrhea being an effect of uterine contractions in the endometrium is a consequential health concern that may hamper a woman quality of life and disrupt everyday activities. It is described as pain throughout the menstrual cycle which is one of the most prominent causes of pelvic pain in women. Traditional medicine and Ayurveda has for centuries stipulated and employed herbs to treat a variety of illnesses. These herbs contain various bioactive compounds that can be exploited to cure serious health complications of human body. The Purpose of this manuscript is to review every aspect of the menstrual cycle and its mechanism, as well as the application of various conventional treatments and herbal remedies. Numerous scientific studies have been carried out over the past several decades with the ultimate objective of preserving the traditional knowledge of medicinal herbs employed in food and medicine. Herbals like ginger, chamomile, fennel, saffron, onion, nimm primary compounds include Gingerols, terpenoids, flavonoids, coumarins, phyto-molecules, thiosulfanates that possess anti-inflammatory, anti-tumor activities, anti-hyperglycemia, and analgesic properties, which can lower the pain during dysmenorrhea. Literature was searched and data was collected related to herbs from different sources like Pubmed, Google scholar, Science direct. Despite many studies and research, there are many factors that need more information related to herbal medicines and it is necessary to acquire more knowledge about the pertinent hormonal balance induced by herbal remedies.

A Molecularly Imprinted Polymer-Based Porous Silicon Optical Sensor for Quercetin Detection in Wines

Quercetin (QU), a bioactive flavonoid with significant nutritional and antioxidant properties, plays a vital role in the quality and stability of wine. This study presents the development of a molecularly imprinted polymer (MIP)-based optical sensor for the selective and sensitive detection of quercetin in red and white wines. The sensor combines the selective molecular recognition capabilities of MIPs with the optical properties of nanostructured porous silica (PSiO2) scaffolds, which serve as the transducer. MIP synthesis was achieved through a novel room-temperature vapor-phase polymerization method using pyrrole as the functional monomer. Computational simulations were used to optimize pyrrole interactions with QU and at the polymer level, to explore the binding interactions of QU with the resulting polypyrrole (PPy) matrix. Comprehensive characterization including UV-vis reflectance spectroscopy and advanced surface analyses confirmed successful MIP formation. The sensor exhibited high sensitivity in a dual linear response range (2.5-80 μM and 80-200 μM), with a detection limit of 0.7 μM. Selectivity tests against structurally similar flavonoids and antioxidants demonstrated a significantly higher response to quercetin, with an imprinting factor of 3.6. The sensor was validated using real wine samples, demonstrating the ability to detect quercetin without prior sample preparation. Results showed strong agreement with high-performance liquid chromatography (HPLC), confirming the sensor reliability. Additionally, the sensor exhibited excellent reusability with minimal signal variation (RSD = 2.6%) and good stability over 60 days (RSD = 3%). This work highlights the potential of MIP-based optical sensors for the real-time monitoring of bioactive compounds in complex food matrices, such as wine, offering a robust and cost-effective alternative for quality control applications.

Time-sensitive effects of quercetin on rat basophilic leukemia (RBL-2H3) cell responsiveness and intracellular signaling

Quercetin is known for its ability to inhibit mast cell degranulation and reduce the release of inflammatory mediators. However, it has also been reported to sensitize mast cells, potentially leading to hyperresponsiveness. This necessitates careful optimization of its use in the treatment of chronic inflammatory diseases. To fully harness quercetin's therapeutic potential, this study investigated the effects of quercetin on rat basophilic leukemia (RBL-2H3) cells responsiveness over varying durations of exposure. We employed comprehensive transcriptome analysis and subsequent functional validation of key signaling pathways. Our findings revealed that quercetin initially reduced cell activity with short-term treatment. However, with prolonged exposure, quercetin transiently enhanced both IgE cross-linkage-mediated and non-IgE-mediated responses. Specifically, prolonged quercetin treatment downregulated IgE-mediated degranulation and FcεRI expression, while potentially sensitizing RBL-2H3 cells to other non-IgE secretagogues through enhanced PKC activity. Given quercetin's multifaceted effects on intracellular signaling pathways, it is crucial to further investigate its efficacy and potential risk of adverse effects. Future studies should focus on a deeper understanding of these mechanisms to optimize quercetin's therapeutic applications while mitigating any possible negative outcomes.

Quercetin protective potential against nanoparticle-induced adverse effects

The rapid development of nanotechnology has resulted in the widespread use of nanoparticles (NPs) in various sectors due to their unique properties and diverse applications. However, the increased exposure of humans to NPs raises concerns about their potential negative impact on human health and the environment. The pathways through which NPs exert adverse effects, including inflammation and oxidative stress, are primarily influenced by their size, shape, surface charge, and chemistry, underscoring the critical need to comprehend and alleviate their potential detrimental impacts. In this context, the natural flavonoid quercetin is a promising candidate for counteracting the toxicity induced by NPs due to its anti-inflammatory and antioxidant properties. This review provides an overview of the existing literature on quercetin's protective effects against NPs-induced toxicity, highlighting its therapeutic benefits and mechanisms of action, focusing on its ability to alleviate oxidative stress, inflammation, and cellular damage caused by various types of NPs. Insights from both in vitro and in vivo studies demonstrate the effectiveness of quercetin in preserving cellular function, modulating apoptotic pathways, and maintaining tissue integrity in the presence of NPs. The potential of quercetin as a natural therapeutic agent against NPs-induced toxicity provides valuable insights for safer use of NPs in various daily applications.

Exploring Advances in Natural Plant Molecules for Allergic Rhinitis Immunomodulation in Vivo and in Vitro

Allergic rhinitis (AR) is a prevalent allergic disease that imposes significant economic burdens and life pressures on individuals, families, and society, particularly in the context of accelerating globalization and increasing pathogenic factors. Current clinical therapies for AR include antihistamines, glucocorticoids administered via various routes, leukotriene receptor antagonists, immunotherapy, and several decongestants. These treatments have demonstrated efficacy in alleviating clinical symptoms and pathological states. However, with the growing awareness of AR and rising expectations for improvements in quality of life, these treatments have become associated with a higher incidence of side effects and an elevated risk of drug resistance. Furthermore, the development of AR is intricately associated with dysregulation of the immune system, yet the underlying pathogenetic mechanisms remain incompletely understood. In contrast, widely available natural plant molecules offer multiple targeting pathways that uniquely modify the typical pathophysiology of AR through immunomodulatory processes. This review presents a comprehensive analysis of both in vivo and in vitro studies on natural plant molecules that modulate immunity for treating AR. Additionally, we examine their specific mechanisms of action in animal models to provide new insights for developing safe and effective targeted therapies while guiding experimental and clinical applications against AR.

Mitochondrial quality control: a pathophysiological mechanism and potential therapeutic target for chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a prevalent chronic respiratory disease worldwide. Mitochondrial quality control mechanisms encompass processes such as mitochondrial biogenesis, fusion, fission, and autophagy, which collectively maintain the quantity, morphology, and function of mitochondria, ensuring cellular energy supply and the progression of normal physiological activities. However, in COPD, due to the persistent stimulation of harmful factors such as smoking and air pollution, mitochondrial quality control mechanisms often become deregulated, leading to mitochondrial dysfunction. Mitochondrial dysfunction plays a pivotal role in the pathogenesis of COPD, contributing toinflammatory response, oxidative stress, cellular senescence. However, therapeutic strategies targeting mitochondria remain underexplored. This review highlights recent advances in mitochondrial dysfunction in COPD, focusing on the role of mitochondrial quality control mechanisms and their dysregulation in disease progression. We emphasize the significance of mitochondria in the pathophysiological processes of COPD and explore potential strategies to regulate mitochondrial quality and improve mitochondrial function through mitochondrial interventions, aiming to treat COPD effectively. Additionally, we analyze the limitations and challenges of existing therapeutic strategies, aiming to provide new insights and methods for COPD treatment.

Network pharmacology integrated with molecular docking and molecular dynamics simulations to explore the mechanism of Shaoyao Gancao Tang in the treatment of asthma and irritable bowel syndrome

BACKGROUND

Numerous studies have demonstrated a correlation between asthma and irritable bowel syndrome (IBS). The Chinese herbal compound Shaoyao Gancao Tang (SYGCT) has been found to have therapeutic effects on both asthma and IBS, but the underlying mechanisms are not yet fully understood. This study aims to explore the key components, key targets, and potential mechanisms of SYGCT in treating asthma with IBS by using network pharmacology, molecular docking techniques and molecular dynamics simulation.

METHODS

The major chemical components and potential target genes of SYGCT were screened by bioinformatics. The key targets of Asthma-IBS comorbidity were identified based on network modules. The intersection of the drug targets and disease targets was identified as the potential targets of SYGCT in treating asthma-IBS. Gene Ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed to identify the biological processes and signaling pathways involved in these potential targets. A protein-protein interaction network was constructed to identify hub targets, while a drug-compound-target topological network was built to screen key compounds. Molecular docking was used to verify the affinity between the hub targets and key compounds. Molecular dynamics analysis was utilized to assess the binding stability of these interactions.

RESULTS

Network pharmacology analysis revealed that the therapeutic effect of SYGCT on asthma-IBS involved multiple biological processes and signaling pathways. It may exert therapeutic effects primarily through signaling pathways such as IL-17, TNF, and Th17 cell differentiation. The possible targets of SYGCT in the treatment of asthma-IBS could be IL6, TNF, JUN, PTGS2, STAT3, IL1B, CASP3, NFKBIA, IL10, and PPARG. Molecular docking verification showed that the predicted targets had good binding affinity with the compounds, among which PTGS2, CASP3, and PPARG had higher binding energy. Molecular dynamics simulation revealed that PTGS2, CASP3, and PPARG proteins had good stability and high binding strength with the compounds 2-[(3R)-8,8-dimethyl-3,4-dihydro-2H-pyrano[6,5-f]chromen-3-yl]-5-methoxyphenol and shinpterocarpin.

CONCLUSION

SYGCT plays a therapeutic role in asthma and IBS through multiple targets and pathways, providing a theoretical basis for explaining the mechanism and clinical application of SYGCT in treating different diseases with the same treatment in asthma and IBS.

Enhanced Bioactivity of Quercetin-Tetrahydroisoquinoline Derivatives: Effect on Lipophilicity, Enzymes Inhibition, Antioxidant Potential, and Cytotoxicity

Quercetin, a well-known flavonoid with significant medicinal potential, was derivatized at the C8 position with a tetrahydroisoquinoline (THIQ) moiety, and physicochemical and pharmacological properties, inhibition potential, antioxidant activity, and cytotoxicity of new compounds were evaluated. Physicochemical and pharmacological properties, including lipophilicity, membrane permeability, and P-glycoprotein substrate affinity, were assessed theoretically using the SwissADME software. The metal-chelating ability of the new compounds was evaluated on metal ions Fe2+, Zn2+, and Cu2+, whose homeostasis disruption is linked to the development of Alzheimer's disease. Inhibition potential was tested on the cholinergic enzymes acetylcholinesterase and butyrylcholinesterase, as well as Na+, K+-ATPase, an enzyme commonly overexpressed in tumours. Antioxidant potential was assessed using the DPPH assay. Cytotoxicity studies were conducted on healthy MRC-5 cells and three cancer cell lines: HeLa, MDA-231, and MDA-468. The results indicated that derivatization of quercetin with THIQ yielded compounds with lower toxicity, preserved chelating ability, improved antioxidant potential, increased selectivity toward the cholinergic enzyme butyrylcholinesterase, and enhanced inhibition potential toward Na+, K+-ATPase and butyrylcholinesterase compared to quercetin alone. Therefore, the synthesized derivatives represent compounds with an improved profile and could be promising candidates for further optimization in developing drugs for neurodegenerative and cancer diseases.

Quercetin and its potential therapeutic effects on aluminum phosphide-induced cardiotoxicity in rats: Role of NOX4, FOXO1, ERK1/2, and NF-κB

Acute Aluminum phosphide (AlP) poisoning poses a serious global issue, yet the exact mechanisms behind AlP-induced cardiotoxicity are still not well understood. Moreover, there is no specific antidote available for AlP toxicity. Nevertheless, Quercetin (QE) has emerged as a promising therapeutic candidate in various contexts. Accordingly, our study aimed to evaluate the QE potential therapeutic effects against AlP-induced cardiotoxicity and the mechanisms underlying such effects. Rats were assigned into four groups: Group I (control group), Group II (vehicle (corn oil) group), Group III (AlP group) received a single dose of AlP (10 mg/kg body weight) dissolved in corn oil by oral gavage, and Group IV (AlP + QE group) received a single dose of QE (400 mg/kg body weight) dissolved in saline, one hour after AlP administration. AlP-induced cardiotoxicity was evidenced by the increase in cardiac troponin I (cTnI) as well as the hemodynamic, ECG, and histopathological abnormalities. The AlP group denoted a decrease of the antioxidant enzymes; catalase and SOD and an increase of the lipid peroxidation marker; MDA. This was associated with a notable increase in inflammatory cytokines (TNFα, IL-6, and IL1β), in addition to a significant upregulation of the expression of NOX4, FOXO1, ERK1/2, and NF-κB. Moreover, Caspase3, and BAX showed strong immunopositive expression, while Bcl-2 showed mild immunoexpression. On the other hand, treatment with QE showed an improvement in the cardiotoxic effects of AlP, as indicated by significant enhancements in biomarkers, functional assessments, and histopathological findings. These results suggest that QE may be a promising candidate for treating AlP-induced cardiotoxicity, attributed to its antioxidant, anti-inflammatory, and anti-apoptotic properties, particularly emphasizing the roles of NOX4, FOXO1, ERK1/2, and NF-κB.

Luteolin Protects against Vascular Calcification by Modulating SIRT1/CXCR4 Signaling Pathway and Promoting Autophagy

Vascular calcification (VC) is a common pathological manifestation of atherosclerosis, hypertension, diabetes vascular disease, vascular injury, chronic kidney disease and aging, which is mainly manifested as increased stiffness of the vascular wall. Oxidative stress and autophagy dysfunction are key factors in the pathogenesis of vascular calcification, but the specific mechanisms and the therapeutic strategy of vascular calcification have not been clarified. In the present study, Sirtuin 1 (SIRT1) was screened as the therapeutic targets for vascular calcification by the bioinformatics. SIRT1 is a nicotinamide adenine dinucleotide, which plays an important role in inhibiting oxidative stress and promoting autophagy. Luteolin (LUT), a kind of natural tetrahydroxyl flavonoid, exists in many plants and has many pharmacological effects such as anti-oxidation and anti-apoptosis. We have reported that luteolin has certain anti-osteoporosis effects in the previous study, and it is accepted that the development of vascular calcification is similar to bone formation, indicating that luteolin may also resist vascular calcification. And luteolin is known to activate SIRT1 to some extent. Moreover, the molecular docking analysis predicted that SIRT1 could bind directly to luteolin. Therefore, the purpose of this study was to investigate the potential role of luteolin in inhibiting oxidative stress and promoting autophagy during vascular calcification via modulating SIRT1 expression. The results showed that luteolin significantly improved vascular calcification induced by a high-fat diet (HFD) and vitamin D3 in rats in vivo. In addition, luteolin significantly repressed the formation of mineralized nodules and ALP activity in H2O2-treated A7r5 cells. Luteolin reduced the level of MDA, LDH and ROS generation, inhibited the protein expression of cleaved caspase-3, cleaved caspase-9, β-catenin and BMP-2 in the aortic tissue of the rat and rat smooth muscle cells (A7r5) treated with hydrogen peroxide. At the same time, luteolin could promote the expression of autophagy related proteins. Moreover, luteolin also produced effects to increase the protein expression levels of SIRT1 more than 2 times both in vivo and in vitro. In terms of mechanism, luteolin attenuated vascular calcification by inhibiting oxidative stress and improving autophagy level, via modulating SIRT1 / CXCR4 signaling pathway. In conclusion, this experiment for the first time revealed that LUT protected against VC via modulating SIRT1 / CXCR4 signaling pathway to promote autophagy and inhibit vascular calcification and may be developed as a new therapeutic agent for vascular calcification and atherosclerosis.

Therapeutic Effects of Vitamins and Nutritional Supplements on Sinusitis: A Narrative Review

Sinusitis, one of the most prevalent and undertreated disorders, is a term used to describe inflammation of the paranasal sinuses caused by either infectious or non-infectious sources. Bacterial, viral, or fungal infections can all cause sinusitis. Sinusitis is classified into 3 types: acute, subacute, and chronic. Acute sinusitis lasts for less than 1 month, subacute sinusitis lasts from 1 to 3 months, and chronic sinusitis persists for over 3 months. This condition affects a significant portion of the population, imposing a substantial burden on the healthcare system. Antibiotics are the gold standard of bacterial sinusitis treatment. However, due to the rise of antimicrobial resistance, especially in immune-compromised patients, it is necessary to investigate potential adjunctive therapies. Based on the literature, vitamins (eg, vitamin D) have antioxidant, anti-inflammatory, and immune-modulatory properties and may effectively treat sinusitis and reduce mucous membrane inflammation. Besides vitamins, many other supplements like quercetin, sinupret, and echinacea have immunomodulatory effects and have shown promising results in sinusitis treatment. In this review, we look at the therapeutic role, safety, and efficacy of vitamins and nutritional supplements in sinusitis treatment.

Quercetin inhibits ferroptosis through the SIRT1/Nrf2/HO-1 signaling pathway and alleviates asthma disease

Background

Quercetin (QCT) is a bioflavonoid derived from vegetables and fruits that has anti-inflammatory and anti-ferroptosis effects against various diseases. Previous studies have shown that QCT modulates the production of cellular inflammatory factors in asthma models and delays the development of chronic airway inflammation. However, the regulatory mechanism of QCT, a traditional Chinese medicine, in the treatment of asthma has not been elucidated. The aim of the present study is to investigate whether QCT can inhibit ferroptosis via the SIRT1/Nrf2 pathway and play a therapeutic role in asthma.

Methods

An ovalbumin-induced mouse asthma model was established, and its function was verified by hematoxylin eosin staining, enzyme linked immunosorbent assay, ferric ion assay, malondialdehyde and superoxide dismutase assays, dihydroethidium staining, immunohistochemical staining, western blotting, and quantitative real-time polymerase chain reaction.

Results

Our results indicated that an ovalbumin-induced asthma mouse model had been successfully established and that QCT inhibited inflammation, reduced serum levels of inflammatory factors IL-4, IL-5 and IL-13, increased superoxide dismutase levels in lung tissue homogenates, and reduced malondialdehyde and ferric ion production in asthmatic mice. In addition, we found that QCT was able to reverse the expression of SIRT1, Nrf2 and HO-1 in an in vivo asthma mouse model.

Conclusions

The data from this study indicate that QCT can alleviate asthma, and its mechanism is related to the regulation of ferroptosis, oxidative stress, and the expression of SIRT1 protein.

The Role of Transforming Growth Factor-β (TGF-β) in Asthma and Chronic Obstructive Pulmonary Disease (COPD)

Asthma and chronic obstructive pulmonary disease (COPD) represent chronic inflammatory respiratory disorders that, despite having distinct pathophysiological underpinnings, both feature airflow obstruction and respiratory symptoms. A critical component in the pathogenesis of each condition is the transforming growth factor-β (TGF-β), a multifunctional cytokine that exerts varying influences across these diseases. In asthma, TGF-β is significantly involved in airway remodeling, a key aspect marked by subepithelial fibrosis, hypertrophy of the smooth muscle, enhanced mucus production, and suppression of emphysema development. The cytokine facilitates collagen deposition and the proliferation of fibroblasts, which are crucial in the structural modifications within the airways. In contrast, the role of TGF-β in COPD is more ambiguous. It initially acts as a protective agent, fostering tissue repair and curbing inflammation. However, prolonged exposure to environmental factors such as cigarette smoke causes TGF-β signaling malfunction. Such dysregulation leads to abnormal tissue remodeling, marked by excessive collagen deposition, enlargement of airspaces, and, thus, accelerated development of emphysema. Additionally, TGF-β facilitates the epithelial-to-mesenchymal transition (EMT), a process contributing to the phenotypic alterations observed in COPD. A thorough comprehension of the multifaceted role of TGF-β in asthma and COPD is imperative for elaborating precise therapeutic interventions. We review several promising approaches that alter TGF-β signaling. Nevertheless, additional studies are essential to delineate further the specific mechanisms of TGF-β dysregulation and its potential therapeutic impacts in these chronic respiratory diseases.

Dietary Polyphenols, Plant Metabolites, and Allergic Disorders: A Comprehensive Review

Given the ongoing rise in the occurrence of allergic disorders, alterations in dietary patterns have been proposed as a possible factor contributing to the emergence and progression of these conditions. Currently, there is a significant focus on the development of dietary therapies that utilize natural compounds possessing anti-allergy properties. Dietary polyphenols and plant metabolites have been intensively researched due to their well-documented anti-inflammatory, antioxidant, and immunomodulatory characteristics, making them one of the most prominent natural bioactive chemicals. This study seeks to discuss the in-depth mechanisms by which these molecules may exert anti-allergic effects, namely through their capacity to diminish the allergenicity of proteins, modulate immune responses, and modify the composition of the gut microbiota. However, further investigation is required to fully understand these effects. This paper examines the existing evidence from experimental and clinical studies that supports the idea that different polyphenols, such as catechins, resveratrol, curcumin, quercetin, and others, can reduce allergic inflammation, relieve symptoms of food allergy, asthma, atopic dermatitis, and allergic rhinitis, and prevent the progression of the allergic immune response. In summary, dietary polyphenols and plant metabolites possess significant anti-allergic properties and can be utilized for developing both preventative and therapeutic strategies for targeting allergic conditions. The paper also discusses the constraints in investigating and broad usage of polyphenols, as well as potential avenues for future research.

Mechanisms of action of Shizhenqing granules for eczema treatment: Network pharmacology analysis and experimental validation

Background

Jiuwan decoction has been used to treat chronic eczema since the Qing Dynasty. According to clinical experience, Shizhenqing granules (SZQG), derived from the Jiuwan decoction, exert beneficial clinical effects on acute eczema and reduce recurrence. Therefore, we elucidated the underlying mechanisms of SZQG through network pharmacology, molecular docking, and experimental validation.

Methods

The main chemical components of SZQG were identified by ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). And the targets of SZQG against eczema were screened out through online databases. Then, the regulatory network map of the "herbal compound-potential target" and the target protein-protein interaction (PPI) network was constructed. The Gene Ontology (GO) analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted using by R language. Additionally, the interaction between the active compounds and the targets was verified by molecular docking technology. Finally, an experiment in vivo was used to verify the effect and mechanism of SZQG on eczema.

Results

Using UHPLC-MS/MS, 158 main chemical compounds of SZQG were identified, and 72 compounds were selected according to the criteria for further analysis. All 237 potential targets of SZQG in eczema were explored using multiple online databases. The network with 14 core targets was screened out, including STAT3, RELA, TNF, JUN, MAPK3, IL-6, PIK3CA, STAT1, MAPK14, MAPK1, IL-4, NFKBIA, IL1B, and MYC. KEGG analyses indicated that the therapeutic effects of SZQG on eczema were predominantly associated with cytokine-cytokine receptor interaction, TNF, MAPK, NF-κB, toll-like receptor, T cell receptor, and Th1 and Th2 cell differentiation signaling pathways. Furthermore, the good affinity between the core compounds and core targets was verified by molecular docking technology, particularly for RELA and MAPK. Animal experiments revealed that SZQG downregulated MAPK14, RELA, T-bet, and GATA3 mRNA expression, reduced immunoglobulin E (IgE) and interleukin-4 (IL-4) serum concentrations, and improved eczema-like lesions in model rats.

Conclusion

This study identified potential targets and signaling pathways of SZQG in the treatment of eczema, whereby RELA and MAPK14 may constitute the main therapeutic targets of SZQG in cytokine regulation and reduction of inflammatory responses.

Covalent conjugation with quercetin mitigates allergenicity of the bee pollen allergen Bra c p in a murine model

Profilin family members are highly conserved food allergens that can cause widespread cross-allergic reactions. Our previous research has demonstrated that the covalent conjunction with quercetin can disrupt the conformational epitopes of a profilin allergen, Bra c p. In this study, we further investigated the intrinsic molecular mechanisms using molecular dynamics simulations. Moreover, the allergenic potential of Bra c p and its conjugate with quercetin was assessed in BALB/c mice. The results showed that continuous interaction with quercetin increased the molecular motion of Bra c p, causing changes to its α-helices and exposing hydrophobic residues which altered antigenic epitopes. Additionally, mice treated with Bra c p-quercetin conjugate showed reduced allergic reactions compared to those treated with Bra c p alone by regulating purine metabolism, calcium signaling, and CD4+CD25+ Tregs proportion. Quercetin conjugation decreases the allergenicity of Bra c p, providing a scientific foundation for reducing the profilin allergens in food.

Reducing the allergenicity of tropomyosin in shrimp by covalent conjugation with quercetin and chlorogenic acid

The study aimed to assay the allergenicity of shrimp tropomyosin (TM) following covalent conjugation with quercetin (QR) and chlorogenic acid (CA). The structure of the TM-polyphenol covalent conjugates was examined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), circular dichroism (CD), fluorescence, differential scanning calorimetry (DSC), and Fourier Transform infrared spectroscopy (FTIR). Potential allergenicity was evaluated using in vitro and in vivo methods. The results showed that QR and CA induced structural changes in TM through aggregation. RBL-2H3 cell results showed that TM-QR and TM-CA covalent conjugates reduced the release of β-hexosaminidase and histamine, respectively. In the mice model, TM-QR and TM-CA covalent conjugates reduced the level of IgE, IgG, IgG1, histamine, and mMCP-1 in sera. Furthermore, the allergenicity was reduced by suppressing Th2-related cytokines (IL-4, IL-5, IL-13) and promoting Th1-related cytokines (IFN-γ). These research findings demonstrate that the covalent binding of TM with QR and CA, modifies the allergenic epitopes of shrimp TM, thereby reducing its potential allergenicity. This approach holds practical applications in the production of low-allergenicity food within the food industry.

Quercetin may reduce the risk of developing the symptoms of COVID-19

Objective

Recent evidence reported that some dietary compounds like quercetin and apigenin as the most well-known flavonoids with anti-inflammatory effects may inhibit SARS-CoV-2 main protease. The hypothesis of the promising effects and possible mechanisms of action of quercetin against COVID-19 were assessed in this article.

Materials and Methods

Related papers on the inhibitory effects of quercetin against COVID-19 were collected using the following search strategy: "corona or coronavirus or COVID or COVID-19 or viral or virus" AND "nutrient or flavonoid or Quercetin".

Results

The findings indicated that quercetin can be considered an effective agent against COVID-19 because of its SARS-CoV-2 main protease and RNA-dependent RNA polymerase inhibitory effects. In addition, quercetin may attenuate angiotensin-converting enzyme-2 (ACE-2) receptors leading to a reduction of SARS-CoV-2 ability to enter host cells. Moreover, the antiviral, anti-inflammatory, and immunomodulatory activities of quercetin have been frequently reported.

Conclusion

Quercetin may be an effective agent for managing the complications of COVID-19. Further longitudinal human studies are warranted.

Zhisou powder displays therapeutic effect on chronic bronchitis through inhibiting PI3K/Akt/HIF-1α/VEGFA signaling pathway and reprograming metabolic pathway of arachidonic acid

ETHNOPHARMACOLOGICAL RELEVANCE

Zhisou Powder (ZP), one of the most common prescriptions in traditional Chinese medicine, has been widely used in the treatment of acute or chronic bronchitis and chronic cough. The ZP was composed of Ziwan (Aster tataricus L. f.), Jiegeng (Platycodon grandiflorus (Jacq.) A. DC.), Jingjie (Nepeta cataria L.), Baibu (Stemona sessilifolia (Miq.) Miq.), Baiqian (Vincetoxicum glaucescens (Decne.) C. Y. Wu & D. Z. Li), Chenpi (Citrus × aurantium f. deliciosa (Ten.) M. Hiroe) and Gancao (Glycyrrhiza uralensis Fisch. ex DC.), with plant names among it checked with MPNS (http://mpns.kew.org). But until now, the key active components and targets of ZP, and related mechanism of ZP in the treatment of chronic bronchitis (CB) remain unclear.

AIM OF THE STUDY

This study combined UPLC-Q-Exactive-Orbitrap-MS, network pharmacology, metabonomics with experiment verification to explore potential mechanism of ZP in the treatment of CB.

MATERIALS AND METHODS

UPLC-Q-Exactive-Orbitrap-MS was performed to analyze the chemical components of ZP. The potentially effective components, attractive targets and critical signaling pathways of Zhisou Powder in the treatment of CB were screened by UPLC-Q-Exactive-Orbitrap-MS combined with network pharmacology. Additionally, the CB model rats induced by SO2 were used to evaluate the anti-chronic bronchitis activity of ZP in vivo. The pulmonary pathology was determined by hematoxylin-eosin staining. Meanwhile, PI3K/Akt/HIF-1α/VEGFA signaling pathway predicted from network pharmacology was verified by Western blot and RT-PCR. Lastly, the metabolic changes of arachidonic acid (AA) in ZP-treated rats were quantitatively analyzed by LC-MS targeted metabonomics, and the proteins expression involved in AA metabolic pathway were detected by immunohistochemistry, immunofluorescence and Western blot.

RESULTS

The main active components of ZP in the treatment of CB selected by network pharmacology and UPLC-Q-Exactive-Orbitrap-MS technology were quercetin, kaempferol, luteolin, galangin, isorhamnetin, naringenin, nobiletin, formononetin and so on. The core targets of these components were predicted to be TP53, TNF, IL-6, VEGFA, CASP3, IL-1β, JUN, PTGS2. Enrichment of KEGG pathway analysis found that PI3K/Akt/HIF-1α/VEGFA signaling pathway might play a key role in the treatment of CB with ZP. The in vivo study showed that ZP significantly improved the pathological changes of SO2-treated lung tissue and inhibited the activation of PI3K/Akt/HIF-1α/VEGFA signaling pathway. The changes of AA and its metabolites in vivo were studied by targeted metabonomics, and it showed that ZP could reprogram the disorder of AA metabolism which contributed to the treatment of CB with ZP.

CONCLUSION

ZP displayed good therapeutic effect on CB model rats through inhibiting PI3K/Akt/HIF-1α/VEGFA signaling pathway to exhibit anti-inflammatory effect and reprogramming disordered metabolic pathway of arachidonic acid.

Network Pharmacology and Experimental Validation Explore the Pharmacological Mechanisms of Herb Pair for Treating Rheumatoid Arthritis

OBJECTIVE

This study aimed to elucidate the multitarget mechanism of the Mori Ramulus - Taxilli Herba (MT) herb pair in treating rheumatoid arthritis (RA).

METHODS

The targets of the herb pair and RA were predicted from databases and screened through cross-analysis. The core targets were obtained using protein-protein interaction (PPI) network analysis. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed. Finally, animal experiments were conducted to validate the anti-RA effect and mechanism of this herb pair.

RESULTS

This approach successfully identified 9 active compounds of MT that interacted with 6 core targets (AKT1, TNF, IL6, TP53, VEGFA, and IL1β). Pathway and functional enrichment analyses revealed that MT had significant effects on the TNF and IL-17 signaling pathways. The consistency of interactions between active components and targets in these pathways was confirmed through molecular docking. Moreover, the potential therapeutic effect of MT was verified in vivo, demonstrating its ability to effectively relieve inflammation by regulating these targeted genes and pathways.

CONCLUSION

The present work suggests that the therapeutic effect of MT herb pair on RA may be attributed to its ability to regulate the TNF signaling pathway and IL-17 signaling pathway.

Modulation of the Immune Response to Allergies Using Alternative Functional Foods

Modulation of the allergic immune response through alternative therapies is a field of study that aims to address allergic reactions differently from traditional approaches. These therapies encompass the utilization of natural functional foods, which have been observed to exert an influence on the immune response, thus mitigating the severity of allergies. Indeed, some studies suggest that the incorporation of these nutraceuticals can regulate immune function, leading to a reduction in histamine release and subsequent alleviation of allergic symptoms. Moreover, certain herbs and dietary supplements, such as curcumin, are believed to possess anti-inflammatory properties, which may serve to moderate allergic responses. Although the results remain somewhat mixed and require further research, these alternative therapies exhibit the potential to impact the allergic immune response, thereby providing complementary options to conventional treatments. Therefore, in this review, we aim to provide an updated account of functional foods capable of modulating the immune response to allergies. In that sense, the review delves into functional foods sourced from plants (phytochemicals), animals, and marine algae. Emphasis is placed on their potential application in the treatment of allergic disorders. It also provides an overview of how these foods can be effectively utilized as functional foods. Additionally, it explores the molecular mechanisms and scientific validity of various bioactive natural compounds in the management of allergies.

The Utilization of Plant-Material-Loaded Vesicular Drug Delivery Systems in the Management of Pulmonary Diseases

Medicinal plants have been utilized to treat a variety of conditions on account of the bioactive properties that they contain. Most bioactive constituents from plants are of limited effectiveness, due to poor solubility, limited permeability, first-pass metabolism, efflux transporters, chemical instability, and food-drug interactions However, when combined with vesicular drug delivery systems (VDDS), herbal medicines can be delivered at a predetermined rate and can exhibit site-specific action. Vesicular drug delivery systems are novel pharmaceutical formulations that make use of vesicles as a means of encapsulating and transporting drugs to various locations within the body; they are a cutting-edge method of medication delivery that combats the drawbacks of conventional drug delivery methods. Drug delivery systems offer promising strategies to overcome the bioavailability limitations of bioactive phytochemicals. By improving their solubility, protecting them from degradation, enabling targeted delivery, and facilitating controlled release, drug delivery systems can enhance the therapeutic efficacy of phytochemicals and unlock their full potential in various health conditions. This review explores and collates the application of plant-based VDDS with the potential to exhibit protective effects against lung function loss in the interest of innovative and effective treatment and management of respiratory illnesses.

Quercetin improves the imbalance of Th1/Th2 cells and Treg/Th17 cells to attenuate allergic rhinitis

Allergic rhinitis (AR) is a common inflammation that affects many people globally. Quercetin has anti-allergic biological activity in AR. Here, we aimed to explore the effects of quercetin on type 1 helper T (Th1)/Th2 and regulatory T cells (Treg)/Th17 balance. We established an ovalbumin (OVA)-induced mouse model and orally administered 20, 35, and 50 mg/kg/day quercetin. The nasal symptoms of mice were observed. The immunoglobulin levels, Treg/Th17-related factors, and pro-inflammatory factors were examined by ELISA. The differentiated inflammation cells were visualized using the diff-quick staining assay. The nasal histopathology was evaluated using H&E, periodic acid Schiff (PAS), and Giemsa staining assay. The results showed that quercetin attenuated OVA-induced rubbing and sneezing. Quercetin reduced IgE, IgG1, histamine, and increased IgG2 in serum. The number of differentiated inflammation cells and goblet cells in tissues that elevated by OVA was reduced by quercetin. Moreover, OVA increased the Treg cell percentage, the levels of IL-17, TGF-β, IL-6, TNF-α, and decreased Th17 cell percentage, IL-10 and FOXP3 levels, while quercetin abrogated their levels induced by OVA. Additionally, quercetin inactivated the NF-κB pathway. Taken together, quercetin attenuated AR symptoms by balancing the Th1/Th2, Treg/Th17 ratios, and inactivating the NF-κB pathway. The results suggested that quercetin may use for AR treatment.

Dietary Polyphenols-Natural Bioactive Compounds with Potential for Preventing and Treating Some Allergic Conditions

In light of the constantly increasing prevalence of allergic diseases, changes in dietary patterns have been suggested as a plausible environmental explanation for the development and progression of these diseases. Nowadays, much attention has been paid to the development of dietary interventions using natural substances with anti-allergy activities. In this respect, dietary polyphenols have been studied extensively as one of the most prominent natural bioactive compounds with well-documented anti-inflammatory, antioxidant, and immunomodulatory properties. This review aims to discuss the mechanisms underlying the potential anti-allergic actions of polyphenols related to their ability to reduce protein allergenicity, regulate immune response, and gut microbiome modification; however, these issues need to be elucidated in detail. This paper reviews the current evidence from experimental and clinical studies confirming that various polyphenols such as quercetin, curcumin, resveratrol, catechins, and many others could attenuate allergic inflammation, alleviate the symptoms of food allergy, asthma, and allergic rhinitis, and prevent the development of allergic immune response. Conclusively, dietary polyphenols are endowed with great anti-allergic potential and therefore could be used either for preventive approaches or therapeutic interventions in relation to allergic diseases. Limitations in studying and widespread use of polyphenols as well as future research directions are also discussed.

[Quercetin induces hepatic stellate cell apoptosis by inhibiting the PI3K/Akt signaling pathway via upregulating miR-146]

OBJECTIVE

To investigate whether quercetin induces apoptosis of hepatic stellate cells by regulating miR-146 to inhibit the PI3K/Akt signaling pathway.

METHODS

Rat hepatic stellate cells (HSC-T6) were treated with TGF-β and different concentrations (40, 60 and 80 μmol/L) of quercetin, and the changes in cell proliferation and apoptosis were detected using CCK-8 assay and flow cytometry. RT-qPCR was used to detect the expression of miR-146 and mRNA expressions of α-SMA, collagenⅠ, TRAF6, PI3K and Akt in the treated cells, and the protein expressions of α-SMA, collagenⅠ, TRAF6, PI3K, Akt and p-Akt were detected using Western blotting. Immunofluorescence assay was used to detect the protein expression of α-SMA and collagenⅠ. The effects of transfection with miR-146 mimic and inhibitor on the protein expressions of the cells were also examined using Western blotting.

RESULTS

Treatment with quercetin dose- and time-dependently inhibited the proliferation of HSC-T6 cells and significantly increased the total cell apoptosis rate (P<0.01). TGF-β-stimulated HSC-T6 cells showed significantly increased mRNA and protein expression levels of α-SMA, collagenⅠ, TRAF6, PI3K and Akt (P<0.05), which were significantly down-regulated by quercetin treatment (P<0.05). Quercetin significantly upregulated the expression of miR-146 in HSC-T6 cells (P<0.01), Transfection of the cells with miR-146 mimic significantly decreased the mRNA and protein expression levels of α-SMA, collagen Ⅰ, TRAF6, PI3K and Akt (P<0.05), and miR- 146 inhibitor produced the opposite effects (P<0.05).

CONCLUSION

Quercetin inhibits proliferation and promotes apoptosis of HSCs by upregulating miR-146 to inhibit the PI3K/Akt signaling pathway.

Sexual dimorphic metabolic and cognitive responses of C57BL/6 mice to Fisetin or Dasatinib and quercetin cocktail oral treatment

Senolytic treatment in aged mice clears senescent cell burden leading to functional improvements. However, less is known regarding the effects of these compounds when administered prior to significant senescent cell accumulation. From 4-13 months of age, C57BL/6 male and female mice received monthly oral dosing of either 100 mg/kg Fisetin or a 5 mg/kg Dasatinib (D) plus 50 mg/kg Quercetin (Q) cocktail. During treatment, several aspects of healthy aging were assayed including glucose metabolism using an insulin and glucose tolerance test, cognitive performance using Morris water maze and novel object recognition, and energy metabolism using indirect calorimetry. Afterwards, mice were euthanized for plasma, tissue specific markers of senescence-associated secretory phenotype (SASP), and white adipose tissue accumulation (WAT). Sexually dimorphic treatment effects were observed. Fisetin treated male mice had reduced SASP, enhanced glucose and energy metabolism, improved cognitive performance, and increased mRNA expression of adiponectin receptor 1 and glucose transporter 4. D + Q treatment had minimal effects in male C57BL/6 mice, but was detrimental to females causing increased SASP expression along with accumulation of WAT depots. Reduced energy metabolism and cognitive performance were also noted. Fisetin treatment had no effect in female C57BL/6 mice potentially due to a slower rate of biological aging. In summary, the senolytic treatment in young adulthood, has beneficial, negligible, or detrimental effects in C57BL/6 mice dependent upon sex and treatment. These observations should serve as a note of caution in this rapidly evolving and expanding field of investigation. Male and female C57BL/6 mice were treated with once monthly oral doses of either Dasatinib (D) + Quercetin (Q) or Fisetin from 4-13 months of age. Males treated with Fisetin had reduced SASP markers (blue spheres) as well as improved metabolism (red flame) and cognition. Females treated with D + Q had increased adiposity and SASP markers (red spheres) along with decreased metabolism (blue flame) and cognitive performance. No effects were observed in females treated with Fisetin or males treated with D + Q.

Quercetin action on health and female reproduction in mammals

This paper reviews the current information concerning availability, metabolism of quercetin, its effects on physiological processes and illnesses with focus on the effects, mechanisms of action and areas of possible application of quercetin in control of female reproductive processes, prevention and treatment of their disorders in mammals.The available information demonstrated the ability of quercetin and its analogues to inhibit proliferation and to promote apoptosis, to activate regenerative processes, to treat immune, inflammatory, cardiovascular, neurodegenerative, gastric and metabolic disorders and cancer, to suppress microorganisms, to protect bones and liver, to relieve pain, to improve physical and mental performance, and to prolong life span.The positive influences of quercetin on mammalian female reproductive processes are well documented. It can promote ovarian follicullo- and oogenesis, improve quality of oocytes and embryos, increase fecundity in various species. These effects can be mediated by changes in pituitary and ovarian hormones, growth factors and cytokines, in their receptors and post-receptory signaling pathways. Due to these effect, quercetin can be applicable as biostimulator of reproduction, for prevention, mitigation and treatment of several female reproductive disorders, as well as to increase resistance of female reproductive system to adverse effect of chemotherapy, temperature stress and environmental contaminants.

Inhibitory effect of Sanguisorba hakusanensis Makino ethanol extract on atopic dermatitis-like responses in NC/Nga mice and human keratinocytes

Atopic dermatitis (AD) is an allergic, inflammatory skin disease caused by immune dysregulation. In this study, we investigated anti-atopic and anti-inflammatory activities of Sanguisorba hakusanensis ethanol extract (SHE) both in vivo using NC/Nga mice and in vitro using human HaCaT keratinocytes. Oral administration of SHE suppressed several atopic symptoms associated with house dust mites (induced with Dermatophagoides farinae extract) in NC/Nga mice and decreased serum levels of inflammatory mediators such as immunoglobulin E, histamine, and inflammatory chemokines. Additionally, SHE treatment reduced the infiltration of immune cells such as mast cells and macrophages in AD skin lesions. In vitro, interferon-γ- and tumor necrosis factor-α-stimulated HaCaT cells exhibited increased expression of T helper 1 and 2 chemokines; their expression was inhibited by SHE treatment. The anti-inflammatory effects of SHE treatment involved blocking of the mitogen-activated protein kinase and signal transducer and activator of transcription 1 signaling pathways. In conclusion, SHE exerts potent anti-atopic and anti-inflammatory effects and should be considered for the clinical treatment of AD.

The Role of Diet and Nutrition in Allergic Diseases

Allergic diseases are a set of chronic inflammatory disorders of lung, skin, and nose epithelium characterized by aberrant IgE and Th2 cytokine-mediated immune responses to exposed allergens. The prevalence of allergic diseases, including asthma, allergic rhinitis, and atopic dermatitis, has increased dramatically worldwide in the past several decades. Evidence suggests that diet and nutrition play a key role in the development and severity of allergic diseases. Dietary components can differentially regulate allergic inflammation pathways through host and gut microbiota-derived metabolites, therefore influencing allergy outcomes in positive or negative ways. A broad range of nutrients and dietary components (vitamins A, D, and E, minerals Zn, Iron, and Se, dietary fiber, fatty acids, and phytochemicals) are found to be effective in the prevention or treatment of allergic diseases through the suppression of type 2 inflammation. This paper aims to review recent advances in the role of diet and nutrition in the etiology of allergies, nutritional regulation of allergic inflammation, and clinical findings about nutrient supplementation in treating allergic diseases. The current literature suggests the potential efficacy of plant-based diets in reducing allergic symptoms. Further clinical trials are warranted to examine the potential beneficial effects of plant-based diets and anti-allergic nutrients in the prevention and management of allergic diseases.

Recent Advances in Potential Health Benefits of Quercetin

Quercetin, a flavonoid found in fruits and vegetables, has been a part of human diets for centuries. Its numerous health benefits, including antioxidant, antimicrobial, anti-inflammatory, antiviral, and anticancer properties, have been extensively studied. Its strong antioxidant properties enable it to scavenge free radicals, reduce oxidative stress, and protect against cellular damage. Quercetin's anti-inflammatory properties involve inhibiting the production of inflammatory cytokines and enzymes, making it a potential therapeutic agent for various inflammatory conditions. It also exhibits anticancer effects by inhibiting cancer cell proliferation and inducing apoptosis. Finally, quercetin has cardiovascular benefits such as lowering blood pressure, reducing cholesterol levels, and improving endothelial function, making it a promising candidate for preventing and treating cardiovascular diseases. This review provides an overview of the chemical structure, biological activities, and bioavailability of quercetin, as well as the different delivery systems available for quercetin. Incorporating quercetin-rich foods into the diet or taking quercetin supplements may be beneficial for maintaining good health and preventing chronic diseases. As research progresses, the future perspectives of quercetin appear promising, with potential applications in nutraceuticals, pharmaceuticals, and functional foods to promote overall well-being and disease prevention. However, further studies are needed to elucidate its mechanisms of action, optimize its bioavailability, and assess its long-term safety for widespread utilization.

Quercetin Alleviates Asthma-Induced Airway Inflammation and Remodeling through Downregulating Periostin via Blocking TGF-β1/Smad Pathway

INTRODUCTION

The aim of the study was to discuss whether the anti-asthmatic effect of quercetin is related to periostin and the downstream molecular pathway of quercetin's anti-asthmatic effect.

METHODS

We constructed asthmatic mice, sensitized by ovalbumin, and administrated different treatments into mice according to the experimental design. In this study, we mainly observed the inflammatory response, airway fibrosis, and airway hyperresponsiveness in asthmatic mice. Pathological stains (H&E, PAS, and Masson) were performed. We also detected the inflammation factors and fibrosis-related cytokines by enzyme-linked immunosorbent serologic assay. In addition, we also explored the level of periostin by enzyme-linked immunosorbent serologic assay and Western blot. At the same time, TGF-β1/Smad pathway was also determined by Western blot.

RESULTS

A high expression of periostin was found in asthmatic mice, and quercetin decreases periostin content in bronchoalveolar lavage fluid. Quercetin and OC-20 inhibit airway inflammation response, airway fibrosis, and airway hyperreactivity. Quercetin downregulated TGF-β1/Smad pathway in the lung tissues of asthmatic mice. Anti-asthma role of quercetin is related to periostin. Then deeper mechanical study revealed that inhibiting TGF-β1 could improve asthmatic symptoms, and quercetin exerted the protective effect on asthmatic mice through inhibition of TGF-β1/Smad pathway.

CONCLUSION

Quercetin provided a protective role against asthma via periostin, manifested by mild inflammatory infiltration, reduced goblet cell proliferation, and reduced airway fibrosis. TGF-β1/Smad pathway is an important transduction system, participating in the protective effect of quercetin on asthma.

Regulatory Roles of Flavonoids in Caspase-11 Non-Canonical Inflammasome-Mediated Inflammatory Responses and Diseases

Inflammasomes are multiprotein complexes that activate inflammatory responses by inducing pyroptosis and secretion of pro-inflammatory cytokines. Along with many previous studies on inflammatory responses and diseases induced by canonical inflammasomes, an increasing number of studies have demonstrated that non-canonical inflammasomes, such as mouse caspase-11 and human caspase-4 inflammasomes, are emerging key players in inflammatory responses and various diseases. Flavonoids are natural bioactive compounds found in plants, fruits, vegetables, and teas and have pharmacological properties in a wide range of human diseases. Many studies have successfully demonstrated that flavonoids play an anti-inflammatory role and ameliorate many inflammatory diseases by inhibiting canonical inflammasomes. Others have demonstrated the anti-inflammatory roles of flavonoids in inflammatory responses and various diseases, with a new mechanism by which flavonoids inhibit non-canonical inflammasomes. This review discusses recent studies that have investigated the anti-inflammatory roles and pharmacological properties of flavonoids in inflammatory responses and diseases induced by non-canonical inflammasomes and further provides insight into developing flavonoid-based therapeutics as potential nutraceuticals against human inflammatory diseases.

Exploring potential pharmacological mechanisms of Yiqi Tuomin Decoction in the treatment of allergic rhinitis utilizing network pharmacology prediction and molecular docking-based strategies: experimental research

Yiqi Tuomin Decoction (YTD), which originated from the theory of lung deficiency and cold in Chinese medicine, is a common Chinese herbal formula used against allergic rhinitis (AR). In our otolaryngology department, this prescription has been used to treat so many AR patients with lung-deficiency-related colds for nearly 30 years. However, the mechanism of its ingredient-target is still unclear. Based on our early experiments and clinical case studies, in this paper, we explore the mechanism of YTD systematically against AR using bioinformatic methods of network pharmacology and molecular docking.

Methods

The Traditional Chinese Medicine Systems Pharmacology (TCMSP) database was used to screen the active ingredients and targets of YTD. The AR-related targets were retrieved from OMIM, GeneCards, TTD, DisGeNET, DrugBank databases, and PharmGKB. The Venn database was used to screen the potential core targets. After that, the STRING database was used to construct the protein-protein interaction (PPI) of the core targets and then visualize it by Cytoscape. The Gene Ontology (GO)-enriched processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of the core targets were analyzed by the KOBAS-I database and Sangerbox. Molecular docking was used to assess interactions between potential targets and active ingredients.

Results

A total of 169 active ingredients and 238 targets of YTD were predicted. YTD shared 115 common targets with AR from the Venn database. The GO-enriched processes and KEGG pathways indicate that genes involved in inflammation and oxidative stress, accompanying the MAPK signaling pathway, Th17 cell differentiation, IL-17 signaling pathway, and Th1 and Th2 cell differentiation, may play a mediated effect in YTD. The docking results showed good binding ability between the active ingredients and the selected targets.

Conclusions

Our study systematically indicated the underlying mechanism of YTD against AR from the perspective of bioinformatics. By studying the active ingredients of YTD, we obtained molecular mechanisms and established a reliable method and molecular theoretical basis for the sensible development of Chinese medicine in the treatment of AR.

Neurological damages in COVID-19 patients: Mechanisms and preventive interventions

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus, causes coronavirus disease 2019 (COVID-19) which led to neurological damage and increased mortality worldwide in its second and third waves. It is associated with systemic inflammation, myocardial infarction, neurological illness including ischemic strokes (e.g., cardiac and cerebral ischemia), and even death through multi-organ failure. At the early stage, the virus infects the lung epithelial cells and is slowly transmitted to the other organs including the gastrointestinal tract, blood vessels, kidneys, heart, and brain. The neurological effect of the virus is mainly due to hypoxia-driven reactive oxygen species (ROS) and generated cytokine storm. Internalization of SARS-CoV-2 triggers ROS production and modulation of the immunological cascade which ultimately initiates the hypercoagulable state and vascular thrombosis. Suppression of immunological machinery and inhibition of ROS play an important role in neurological disturbances. So, COVID-19 associated damage to the central nervous system, patients need special care to prevent multi-organ failure at later stages of disease progression. Here in this review, we are selectively discussing these issues and possible antioxidant-based prevention therapies for COVID-19-associated neurological damage that leads to multi-organ failure.

Quercetin 3-O-(6″-O-E-caffeoyl)-β-D-glucopyranoside, a Flavonoid Compound, Promotes Melanogenesis through the Upregulation of MAPKs and Akt/GSK3β/β-Catenin Signaling Pathways

Quercetin 3-O-(6″-O-E-caffeoyl)-β-D-glucopyranoside is a flavonoid compound produced by various plants with reported antiprotozoal potential against E. histolytica and G. lamblia; however, its effects on skin pigment regulation have not been studied in detail. In this investigation, we discovered that quercetin 3-O-(6″-O-E-caffeoyl)-D-glucopyranoside (coded as CC7) demonstrated a more increased melanogenesis effect in B16 cells. CC7 exhibited no cytotoxicity or effective stimulating melanin content or intracellular tyrosinase activity. This melanogenic-promoting effect was accompanied by activated expression levels of microphthalmia-associated transcription factor (MITF), a key melanogenic regulatory factor, melanogenic enzymes, and tyrosinase (TYR) and tyrosinase-related protein-1 (TRP-1) and 2 (TRP-2) in the CC7-treated cells. Mechanistically, we found that CC7 exerted melanogenic effects by upregulating the phosphorylation of stress-regulated protein kinase (p38) and c-Jun N-terminal kinase (JNK). Moreover, the CC7 upregulation of phosphor-protein kinase B (Akt) and Glycogen synthase kinase-3 beta (GSK-3β) increased the content of β-catenin in the cell cytoplasm, and subsequently, it translocated into the nucleus, resulting in melanogenesis. Specific inhibitors of P38, JNK, and Akt validated that CC7 promotes melanin synthesis and tyrosinase activity by regulating the GSK3β/β-catenin signaling pathways. Our results support that the CC7 regulation of melanogenesis involves MAPKs and Akt/GSK3β/β-catenin signaling pathways.

Role of Plant-Derived Compounds in the Molecular Pathways Related to Inflammation

Inflammation is the primary response to infection and injury. Its beneficial effect is an immediate resolution of the pathophysiological event. However, sustained production of inflammatory mediators such as reactive oxygen species and cytokines may cause alterations in DNA integrity and lead to malignant cell transformation and cancer. More attention has recently been paid to pyroptosis, which is an inflammatory necrosis that activates inflammasomes and the secretion of cytokines. Taking into consideration that phenolic compounds are widely available in diet and medicinal plants, their role in the prevention and support of the treatment of chronic diseases is apparent. Recently, much attention has been paid to explaining the significance of isolated compounds in the molecular pathways related to inflammation. Therefore, this review aimed to screen reports concerning the molecular mode of action assigned to phenolic compounds. The most representative compounds from the classes of flavonoids, tannins, phenolic acids, and phenolic glycosides were selected for this review. Our attention was focused mainly on nuclear factor-κB (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), and mitogen-activated protein kinase (MAPK) signaling pathways. Literature searching was performed using Scopus, PubMed, and Medline databases. In conclusion, based on the available literature, phenolic compounds regulate NF-κB, Nrf2, and MAPK signaling, which supports their potential role in chronic inflammatory disorders, including osteoarthritis, neurodegenerative diseases, cardiovascular, and pulmonary disorders.

Development of a Water-Dispersible Supramolecular Complex of Polyphenol with Polypeptides for Attenuation of the Allergic Response using a Mechanochemical Strategy

The prevalence of allergic disorders has increased worldwide in recent decades. Polyphenols, including resveratrol and curcumin, are posited to have potential as therapeutic agents for allergy; however, their use has been limited by poor water solubility. Accordingly, a highly concentrated, water dispersible, supramolecular complexes of polyphenols with polypeptides (poly-L-lysine, poly-γ-glutamic acid) and gelatin using high-speed vibration milling are developed. The complex exhibited resistance to photobleaching and thermal radiation. Treatment of a rat basophilic leukemia cell line (RBL-2H3) with polypeptide complexes containing resveratrol is suppressed allergic responses in vitro. Moreover, aerosolized administration of polypeptide complexes is demonstrated excellent bioavailability and inhibition of immediate hypersensitivity reactions in ear tissue in vivo. Furthermore, the method avoids the use of organic solvent and therefore reduces undesirable biological responses.

Therapeutic effect of oral quercetin in hamsters infected with Leishmania Viannia braziliensis

Leishmaniasis is a parasitic disease caused by several species of intracellular protozoa of the genus Leishmania that present manifestations ranging from cutaneous ulcers to the fatal visceral form. Leishmania Viannia braziliensis is an important species associated with American tegumentary leishmaniasis and the main agent in Brazil, with variable sensitivity to available drugs. The search for new therapeutic alternatives to treat leishmaniasis is an urgent need, especially for endemic countries. Not only is quercetin well known for its antioxidant activity in radical scavenging but also several other biological effects are described, including anti-inflammatory, antimicrobial, and pro-oxidant activities. This study aimed to investigate the flavonoid quercetin's therapeutic potential in L. (V.) braziliensis infection. Quercetin showed antiamastigote (IC50 of 21 ± 2.5 µM) and antipromastigote (25 ± 0.7 µM) activities and a selectivity index of 22. The treatment of uninfected or L. (V.) braziliensis-infected macrophages with quercetin increased reactive oxygen species (ROS)/H202 generation without altering Nitric Oxide (NO) production. Oral treatment with quercetin of infected hamsters, starting at 1 week of infection for 8 weeks, reduced the lesion thickness (p > 0.01) and parasite load (p > 0.001). The results of this study suggest that the antiamastigote activity of the flavonoid quercetin in vitro is associated, at least in part, with the modulation of ROS production by macrophages. The efficacy of oral quercetin treatment in hamsters infected with L. (V.) braziliensis was presented for the first time and shows its promising therapeutic potential.

Safety Considerations for Natural Products Commonly Used By Patients with Allergic Disease

Natural products are a category of Complementary and Alternative Medicine that includes medicinal plants, vitamins, and dietary supplements. These products are often utilized by patients with allergies in conjunction with, or as an alternative to, their conventional medical therapies. Despite the wide use of these modalities, many clinicians often have limited knowledge and training in their use. It is important for health care providers to know the safety and risks of these products that their patients may use. This Clinical Commentary reviews the side effects and adverse reactions of several natural products commonly used by patients with allergies and gives an overview of the U.S. Food and Drug Administration requirements for manufacturing, advertising and distribution.

Evaluation of Two Active System Encapsulant Matrices with Quercetin and Bacillus clausii for Functional Foods

Currently, demand for functional foods is increasing in the public interest in order to improve life expectations and general health. Food matrices containing probiotic microorganisms and active compounds encapsulated into carrier agents are essential in this context. Encapsulation via the lyophilisation method is widely used because oxidation reactions that affect physicochemical and nutritional food properties are usually avoided. Encapsulated functional ingredients, such as quercetin and Bacillus clausii, using two carrier agents' matrices-I [inulin (IN), lactose (L) and maltodextrin (MX)] and II [arabic (A), guar (G), and xanthan (X) gums)]-are presented in this work. A D-optimal procedure involving 59 experiments was designed to evaluate each matrix's yield, viability, and antioxidant activity (AA). Matrix I (33.3 IN:33.3 L:33.3 MX) and matrix II (33.3 A:33.3 G:33.3 X) exhibited the best yield; viability of 9.7 log10 CFU/g and 9.73 log10 CFU/g was found in matrix I (using a ratio of 33.3 IN:33.3 L:33.3 MX) and matrix II (50 G:50 X), respectively. Results for the antioxidant capacity of matrix I (100 IN:0 L:0M X) and matrix II (0 A:50 G:50 X) were 58.75 and 55.54 (DPPH* scavenging activity (10 µg/mL)), respectively. Synergy between matrices I and II with use of 100IN:0L:OMX and 0A:50G:50X resulted in 55.4 log10 CFU/g viability values; the antioxidant capacity was 9. 52 (DPPH* scavenging activity (10 µg/mL). The present work proposes use of a carrier agent mixture to produce a functional ingredient with antioxidant and probiotic properties that exceed the minimum viability, 6.0 log10 CFU/g, recommended by the FAO/WHO (2002) to be probiotic, and that contributes to the recommended daily quercetin intake of 10-16 mg/day or inulin intake of 10-20 g/day and dietary fibre intake of 25-38 g per day.

Quercetin improves pancreatic cancer chemo-sensitivity by regulating oxidative-inflammatory networks

Chemotherapy is the main method for controlling pancreatic cancer metastasis but the prevalent chemotherapy resistance limits its utilization. The response of oxidation and inflammation often promotes pancreatic cancer progression and chemo-resistance. It is critical to explore the potential natural products with few side effects to control inflammatory responses and understand the related mechanisms. Quercetin is a flavonoid widely found in numerous vegetables, fruits, and foods and is thought to have antioxidant and anti-inflammatory properties, which may be associated with improvement of chemotherapy sensitivity during pancreatic cancer treatment. Quercetin may sensitize pancreatic cancer cells to the chemotherapeutic agents, including bromodomain and extraterminal domain inhibitors (BETI), daunorubicin, gemcitabine, sulforaphane, doxorubicin, and tumor necrosis factor-related signaling apoptosis-inducing ligand (TRAIL). Meanwhile, during the chemo-resistance therapy, many signaling molecules are involved with toll-like receptor 4 (TLR4)-mediated oxidative and inflammatory pathway. The effects of quercetin on other oxidative and inflammatory pathways were also explored. Quercetin may exert antitumor activity during the prevention of pancreatic cancer progression by regulating oxidative and inflammatory networks, which can promote immune escape of cancer cells by inducing immunosuppressive cytokines. Studying these patterns will help us to better understand the functional role of quercetin in the improvement of pancreatic cancer chemo-sensitivity. PRACTICAL APPLICATIONS: Chemotherapy is the major way for treating pancreatic cancer metastasis but the prevalent chemotherapy resistance caused by oxidative and inflammatory responses limits its utilization. It is necessary to explore the potential natural products with few side effects to prevent the oxidative and inflammatory responses. Quercetin is a flavonoid widely found in numerous vegetables, fruits, and foods and is thought to have antioxidant and anti-inflammatory properties, which may be associated with improvement of chemotherapy sensitivity of pancreatic cancer treatment by sensitizing pancreatic cancer cells to various chemotherapeutic agents via the regulation of oxidative and inflammatory networks. Studying these patterns will help us to better understand the functional role of quercetin in the improvement of pancreatic cancer chemo-sensitivity.

In Vitro Effect of Flavonoids on Basophils Degranulation and Intestinal Epithelial Barrier Damage Induced by ω-5 Gliadin-Derived Peptide

Flavonoids have antioxidant, anti-inflammatory and immunomodulatory properties, and may alleviate food allergic reactions and intestinal inflammation induced by ω-5 gliadin, a main allergen of wheat food allergy in children. In this study, a human basophil KU812 cell degranulation model and a Caco-2 monolayer cell model were constructed in vitro to evaluate the effects of four flavonoids on the allergenicity of ω-5 gliadin peptides and ω-5 gliadin peptide-induced barrier damage in Caco-2 intestinal epithelial monolayers. The results show that baicalein, luteolin, isorhamnetin and naringenin can significantly inhibit the degranulation of KU812 cells stimulated by ω-5 gliadin-derived peptide P4 and the release of IL-6 and TNF-α. In addition, the four flavonoids significantly inhibited the ω-5 gliadin-derived peptide P4 to induce the release of IL-6, IL-8 in Caco-2 cells, inhibited the release of zonulin, and significantly increase the expression of tight junction proteins Occludin and ZO-1 in the Caco-2 cell monolayer. In conclusion, baicalein, luteolin, isorhamnetin and naringenin inhibit degranulation stimulated by wheat allergen and enhance intestinal barrier functions, which supports the potential pharmaceutical application of the four flavonoids treatment for wheat food allergy.

Molecular Mechanisms Underlying the Effects of Bimin Kang Mixture on Allergic Rhinitis: Network Pharmacology and RNA Sequencing Analysis

Background

Allergic rhinitis (AR) is a highly prevalent chronic inflammatory disease of the respiratory tract. Previous studies have demonstrated that Bimin Kang Mixture (BMK) is effective in alleviating AR symptoms and reducing the secretion of inflammatory factors and mucin; however, the precise mechanisms underlying these effects remain unclear.

Methods

We built target networks for each medication component using a network pharmacology technique and used RNA-seq transcriptome analysis to screen differentially expressed genes (DEGs) for AR patients and control groups. The overlapping targets in the two groups were assessed using PPI networks, GO, and KEGG enrichment analyses. The binding ability of essential components to dock with hub target genes was investigated using molecular docking. Finally, we demonstrate how BMK can treat AR by regulating the NF-κB signaling pathway through animal experiments.

Results

Effective targets from network pharmacology were combined with DEGs from RNA-seq, with 20 intersections as key target genes. The construction of the PPI network finally identified 5 hub target genes, and all hub target genes were in the NF-κB signaling pathway. Molecular docking suggests that citric acid, deoxyandrographolide, quercetin, luteolin, and kaempferol are structurally stable and can spontaneously attach to IL-1β, CXCL2, CXCL8, CCL20, and PTGS2 receptors. Animal experiments have shown that BMK inhibits NF-κB transcription factor activation, reduces the expression of proinflammatory cytokines and chemokines IL-1β, CXCL2, IL-8, and COX-2, and exerts anti-inflammatory and anti-allergic effects.

Conclusion

BMK by regulating the NF-κB signaling pathway improves inflammatory cell infiltration, regulates mucosal immune balance, and reduces airway hypersensitivity. These findings provide theoretical support for the clinical efficacy of BMK for AR treatment.

Allergic Inflammation: Effect of Propolis and Its Flavonoids

The incidence of allergic diseases and their complications are increasing worldwide. Today, people increasingly use natural products, which has been termed a "return to nature". Natural products with healing properties, especially those obtained from plants and bees, have been used in the prevention and treatment of numerous chronic diseases, including allergy and/or inflammation. Propolis is a multi-component resin rich in flavonoids, collected and transformed by honeybees from buds and plant wounds for the construction and adaptation of their nests. This article describes the current views regarding the possible mechanisms and multiple benefits of flavonoids in combating allergy and allergy-related complications. These benefits arise from flavonoid anti-allergic, anti-inflammatory, antioxidative, and wound healing activities and their effects on microbe-immune system interactions in developing host responses to different allergens. Finally, this article presents various aspects of allergy pathobiology and possible molecular approaches in their treatment. Possible mechanisms regarding the antiallergic action of propolis on the microbiota of the digestive and respiratory tracts and skin diseases as a method to selectively remove allergenic molecules by the process of bacterial biotransformation are also reported.

Quercetin and Resveratrol Differentially Decrease Expression of the High-Affinity IgE Receptor (FcεRI) by Human and Mouse Mast Cells

Mast cells (MC) synthesize and store proinflammatory mediators and are centrally important in atopic diseases such as asthma and atopic dermatitis. Quercetin a and resveratrol are plant derived polyphenolic compounds with anti-inflammatory properties that inhibit MC degranulation and mediator release. However, the underlying mechanism of these inhibitory effects on MC is poorly understood and it is unclear whether this is a general effect on all MC phenotypes. We have characterized and compared the effects of quercetin with resveratrol on human (LAD2) and mouse (MC/9 and BMMC) MC mediator release, receptor expression and FcεRI signaling to better understand the mechanisms involved in quercetin and resveratrol-mediated inhibition of MC activation. Quercetin significantly decreased the expression of FcεRI by BMMC and MC/9, although the effects on MC/9 were associated with a significant reduction in cell viability. Quercetin also inhibited antigen-stimulated TNF release by BMMC. Although neither quercetin nor resveratrol significantly altered antigen-stimulated BMMC degranulation or downstream signaling events such as phosphorylation of spleen tyrosine kinase (SYK) or extracellular signal-regulated kinase 1/2 (ERK), resveratrol inhibited ERK phosphorylation and FcεRI- stimulated degranulation in LAD2. Our data suggests that quercetin and resveratrol inhibit human and mouse MC differentially and that these effects are associated with modification of FcεRI expression, signaling (phosphorylation of SYK and ERK) and mediator release.