Quercetin: Its Antioxidant Mechanism, Antibacterial Properties and Potential Application in Prevention and Control of Toxipathy

Valorization of grape pomace extracts against cranberry, elderberry, rose hip berry, goji berry and raisin extracts: Phytochemical profile and in vitro biological activity

The circular economy is gaining attention around the world as a sustainable approach to tackling environmental problems, promoting more responsible management of resources. The aim of this work is the valorization of grape pomace as a waste product of agrifood chain. We prepared decoction (DC), ultrasound-assisted and microwave-assisted extracts (UAE and MAE respectively) of grape pomace, determining their phytochemical profile (using HPLC-ESI-Q-TOF-MS), antioxidant activity and enzyme inhibitory effects. Then, the results were compared with those of raisins and several edible berries already present in the market. Grape pomace extracts presented the highest total phenolic content (62-68 mg gallic acid equivalents/g; mg GAE/g), whereas the concentrations in the other berries were 4-43 mg GAE/g. These results were in agreement with the higher antioxidant activity and tyrosinase inhibition observed in grape pomace compared with the other berries, except for the metal chelating activity. The main compounds in grape pomace extracts were flavonoids (particularly quercetin glycosides), followed by organic acids (citric, isocitric and gallic acids). These results open new perspectives in the development of food supplements and nutraceuticals based on grape pomace extracts.

Organic extracts from sustainable hybrid poplar hairy root cultures as potential natural antimicrobial and antibiofilm agents

In order to meet growing consumer demands in terms of naturalness, the pharmaceutical, food, and cosmetic industries are looking for active molecules of plant origin. In this context, hairy roots are considered a promising biotechnological system for the sustainable production of compounds of interest. Poplars (genus Populus, family Salicaceae) are trees of ecological interest in temperate alluvial forests and are also cultivated for their industrial timber. Poplar trees also produce specialized metabolites with a wide range of bioactive properties. The present study aimed to assess the hybrid poplar hairy root extracts for antimicrobial and antibiofilm activities against four main life-threatening strains of Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria. Ethyl acetate extracts from two hairy root lines (HP15-3 and HP A4-12) showed significant antibacterial properties as confirmed by disc diffusion assay. Antibiofilm activities were found to be dose dependent with significant biofilm inhibition (75-95%) recorded at 1000 µg.mL-1 in all the bacterial strains tested. Dose-dependent enhancement in the release of exopolysaccharides was observed in response to treatment with extracts, possibly because of stress and bacterial cell death. Fluorescence microscopy confirmed loss of cell viability of treated bacterial cells concomitant with increased production of reactive oxygen species compared to the untreated control. Overall, this study demonstrates for the first time a high potential of poplar hairy root extracts as a natural and safe platform to produce antimicrobial agents in pharmaceutical, food, industrial water management, or cosmetic industries.

Insights into the fabrication and antibacterial effect of fibrinogen hydrolysate-carrageenan loading apigenin and quercetin composite hydrogels

Escherichia coli and Staphylococcus aureus are the most prevalent pathogenic bacteria, often resulting in the foodborne disease outbreaks through food spoilage and foodborne infections. To prevent and control food spoilage and foodborne infections induced by Escherichia coli and Staphylococcus aureus, the antibacterial hydrogels were fabricated using fibrinogen hydrolysate-carrageenan (AHs-C) and flavonoids (apigenin and quercetin), and the antibacterial effect of the composite hydrogels against Escherichia coli and Staphylococcus aureus was further investigated. The results of mechanical property exhibited that the composite hydrogels with 0.2 % of apigenin and quercetin (AHs-C-Ap/Que) showed the highest hardness and swelling property compared with the separate addition of apigenin or quercetin. Scanning electron microscopy and atomic force microscopy showed that the dense networks were formed in the hydrogels of AHs-C-Ap/Que., and the average roughness of AHs-C-Ap/Que. significantly increased to 30.70 nm compared with AHs-C. 1H NMR and FTIR spectra demonstrated that apigenin and quercetin were bound to AHs-C by hydrogen bond, hydrophobic interaction and Schiff base, where the interactions between Ap/Que. and AHs-C was stronger compared with the separate addition of apigenin or quercetin. The hydrogels of AHs-C-Ap/Que. showed the highest antibacterial capacity and antibacterial adhesion against Escherichia coli and Staphylococcus aureus. The antibacterial adhesion assay showed that 99 % removal ratios for E. coli and S. aureus were observed in AHs-C-Ap/Que. hydrogels, which showed a great potential to prevent food spoilage and foodborne infections.

Polysaccharide-Based Injectable Hydrogel Loaded with Quercetin Promotes Scarless Healing of Burn Wounds by Reducing Inflammation

Moisture loss, infection, and severe inflammatory reactions are the primary factors affecting burn wound healing and leading to scar formation. Herein, we developed a quercetin-loaded polysaccharide-based injectable hydrogel (named PECE). The PECE consists of oxidized sodium alginate (OAlg) coupled with chitosan (CS) via Schiff bases and electrostatic interactions, while Que is incorporated via hydrogen bonding. Benefiting from the hydroxyl and carboxyl groups, PECE features distinguished moisturizing ability. Additionally, the sustained release of Que imparts remarkable antibacterial activity against Escherichia coli and Staphylococcus aureus. Likewise, PECE demonstrates favorable in vitro anti-inflammatory capacity as released Que significantly downregulates pro-inflammatory factors (IL-6 and TNF-α) secreted by RAW 264.7 macrophages. More importantly, in a rat model of deep second-degree burn wounds, PECE effectively inhibits wound infection, reduces inflammation, and promotes angiogenesis and collagen deposition, ultimately minimizing scar formation. Overall, this work presents a promising strategy for scarless healing of burn wounds.

Antibacterial effects and mechanisms of quercetin-β-cyclodextrin complex mediated photodynamic on Escherichia coli O157:H7

Quercetin is a natural flavonoid with antioxidant, anti-inflammatory, and antibacterial properties. This work aimed to formulate quercetin-cyclodextrin microcapsules (QT-β-CD) while examining their photodynamic antibacterial effects and underlying mechanisms in detail. Characterization of the QT-β-CD was conducted using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The bacteriostatic effects of UV-A irradiation on Escherichia coli O157:H7 (E. coli O157:H7) were investigated. The photodynamic impact of QT-β-CD was assessed by analyzing hydrogen peroxide (H₂O₂) production. The antimicrobial activity was further elucidated through examinations of cell membrane integrity, protein damage, changes in cellular motility, biofilm formation, and extracellular polysaccharide reduction. The effect of QT-β-CD on LuxS and motA gene expression in E. coli O157:H7 was investigated by RT-qPCR. The findings demonstrated that QT-β-CD exhibited potent photodynamic properties and functioned as an efficient photosensitizer, causing substantial damage to E. coli O157:H7 cells. These results underscore the potential of quercetin as an antimicrobial agent for food preservation.

Quercetin, the new stress buster: Investigating the transcriptional and behavioral effects of this flavonoid on multiple stressors using Lymnaea stagnalis

Growing evidence suggests that a flavonoid-rich diet can prevent or reverse the effects of stressors, although the underlying mechanisms remain poorly understood. One common and abundant flavonoid found in numerous foods is quercetin. This study utilizes the pond snail Lymnaea stagnalis, a valid model organism for learning and memory, and a simple but robust learning paradigm-operant conditioning of aerial respiration-to explore the behavioral and transcriptional effects of different stressors on snails' cognitive functions and to investigate whether quercetin exposure can prevent stress effects on learning and memory formation. Our findings demonstrate that three different stressors-severe food deprivation, lipopolysaccharide injection (an inflammatory challenge), and fluoride exposure (a neurotoxic agent)-block memory formation for operant conditioning and affect the expression levels of key targets related to stress response, energy balance, and immune response in the snails' central ring ganglia. Remarkably, exposing snails to quercetin for 1 h before stress presentation prevents these effects at both the behavioral and transcriptional levels, demonstrating the potent stress-preventive properties of quercetin. Despite the evolutionary distance from humans, L. stagnalis has proven to be a valuable model for studying conserved mechanisms by which bioactive compounds like quercetin mitigate the adverse effects of various stressors on cognitive functions across species. Moreover, these findings offer insights into quercetin's potential for mitigating stress-induced physiological and cognitive impairments.

Exploring the potential mechanisms of Mahuang Fuzi Xixin decoction in treating elderly bronchial asthma through network pharmacology, molecular docking, and molecular dynamics simulations

Modern medical practice has confirmed the efficacy of Mahuang Fuzi Xixin Decoction (MHFZXXD) in treating elderly bronchial asthma, but its specific mechanisms of action remain to be clarified. Therefore, this study utilizes network pharmacology, molecular docking techniques, and molecular dynamics simulations to explore the key active components, core target genes, and potential mechanisms of MHFZXXD in the treatment of elderly bronchial asthma. Active components and related targets of MHFZXXD were identified through the retrieval and screening of the TCMSP, Swiss Targets Prediction, and Uniprot databases. Relevant targets for elderly bronchial asthma were searched using the GeneCards, OMIM, and Pharm GKB databases, followed by the selection of intersecting targets between the drug's active components and the disease. A PPI network diagram was created using String and Cytoscape software, and the intersecting targets of the disease and the active components of traditional Chinese medicine were imported into the DAVID database for GO and KEGG enrichment analysis to further explore their potential mechanisms of action. Subsequently, molecular docking and molecular dynamics simulations were performed using AutoDock Vina and Gromacs to verify the binding capacity and stability of the core genes with the key active components. The study results indicate that the active components of MHFZXXD, such as quercetin, luteolin, and kaempferol, target multiple genes including AKT1, EGF, MYC, TGFB1, PTEN, and CCND1. They exert effects through signaling pathways such as TNF, PI3K-Akt, and HIF-1. Molecular docking and dynamics simulations show that the core targets bind stably with the key active components. Overall, MHFZXXD may reduce inflammatory responses and improve hypoxic conditions and apoptosis during the progression of elderly bronchial asthma through multiple active components, targets, and signaling pathways, thereby delaying the malignant progression of the disease. This provides relevant evidence and experimental data for clinical treatment and further research.

Quercetin Alleviates LPS-Stimulated Myocardial Injury through Regulating ALOX5/PI3K/AKT Pathway in Sepsis

Quercetin (QUE) has been found to inhibit the progression of sepsis-related diseases, including sepsis-induced cardiomyopathy (SIC). More information about the role and mechanism of QUE in SIC progression deserves further exploration. Human cardiomyocytes (AC16) were induced with LPS to mimic SIC cell models. Cell proliferation and apoptosis were determined using CCK8 assay, EdU assay, and flow cytometry. Cell inflammation and ferroptosis were evaluated by detecting IL-1β, TNF-α, Fe2+, ROS, GSH, and GPX4 levels. 5-lipoxygenase (ALOX5) expression was examined by quantitative real-time PCR and western blot. LPS treatment reduced AC16 cell proliferation, while enhanced apoptosis, inflammation, and ferroptosis. QUE repressed LPS-induced AC16 cell apoptosis, inflammation, and ferroptosis. ALOX5 was upregulated in SIC patients, and its expression was reduced by QUE. ALOX5 knockdown restrained LPS-induced apoptosis, inflammation, and ferroptosis in AC16 cells. The inhibitory effect of QUE on LPS-induced myocardial injury could be reversed by ALOX5 overexpression. QUE promoted the activity of PI3K/AKT pathway by reducing ALOX5 expression. QUE could alleviate LPS-induced myocardial injury by regulating ALOX5/PI3K/AKT pathway, suggesting that QUE might be used for treating SIC.

Quercetin prevents rats from type 1 diabetic liver damage by inhibiting TGF-ꞵ/apelin gene expression

Background

Hyperglycemia-induced oxidative stress is a significant contributor to diabetic complications, including hepatopathy. The current survey aimed to evaluate the ameliorative effect of quercetin (Q) on liver functional disorders and tissue damage developed by diabetes mellitus in rats.

Methods

Grouping of 35 male Wistar rats was performed as follows: sham; sham + quercetin (sham + Q: quercetin, 50 mg/kg/day in 1 ml 1% DMSO for 6 weeks, by gavage); diabetic control (Diabetes: streptozotocin (STZ), 65 mg/kg, i.p.); diabetic + quercetin 1 (D + Q1: quercetin, 25 mg/kg/day in 1 ml 1% DMSO for 6 weeks, by gavage after STZ injection); and diabetic + quercetin 2 (D + Q2: quercetin, 50 mg/kg/day in 1 ml 1% DMSO for 6 weeks, by gavage after STZ injection). Body weight, food intake, and water intake were measured. Ultimately, the samples of plasma and urine, as well as tissue samples of the liver and pancreas were gathered for later assays.

Results

STZ injection ended in elevated plasma blood glucose levels, decreased plasma insulin levels, liver dysfunction (increased activity levels of AST, ALT, and ALP, increased plasma levels of total bilirubin, cholesterol, LDL, triglyceride, decreased plasma levels of total protein, albumin and HDL), enhanced levels of malondialdehyde, diminished activities of antioxidant enzymes (superoxide dismutase, and catalase), reduced level of glutathione (GSH) increased gene expression levels of apelin and TGF-ꞵ, plus liver histological destruction. All these changes were diminished by quercetin. However, the measure of improvement in the D + Q2 group was higher than that of the D + Q1 group.

Conclusions

Quercetin improved liver function after diabetes mellitus type 1, possibly due to reduced lipid peroxidation, increased antioxidant systems, and inhibiting the apelin/TGF-ꞵ signaling pathway.

Integrated transcriptomic and metabolic analyses reveal the early response mechanism of Pinus tabulaeformis to pine wood nematodes

Pine wilt disease (PWD) is a devastating disease of pine trees caused by the pine wood nematode (Bursapherenchus xylophilus, PWN). To study how Pinus tabulaeformis responds to PWD infection, we collected 3-year-old P. tabulaeformis seedlings at 2 days, 5 days, and 8 days after being infected with B. xylophilus. We identified genes and metabolites early responding to infection using transcriptome and metabolomic data obtained by high-throughput mRNA sequencing (RNA-seq) and liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based assays, respectively. The following results were obtained: (1) After inoculation with PWN, the average number of days taken for 3-year-old P. tabulaeformis seedlings to develop symptoms was 8 days. (2) Combined transcriptome and metabolome analysis revealed that phenylpropanoid biosynthesis and flavonoid biosynthesis are critically important pathways for P. tabulaeformis to respond to PWD. (3) The response of P. tabulaeformis to stress was mainly through positive regulation of gene expression, including some key genes related to plant hormones or transcription factors that have been widely studied. Genes related to pathways such as photosynthesis, plant-pathogen interactions, and DNA replication were downregulated. (4) Terpenoid biosynthesis genes involved during the development of pine wilt disease. This study demonstrated the defence and pathogenic mechanisms of P. tabulaeformis against PWD, providing a reference for the early diagnosis of PWD.

Phytochemical and ethnomedicinal evidences of the use of Alternanthera brasiliana (L.) Kuntze against infectious diseases

ETHNOPHARMACOLOGICAL RELEVANCE

Popularly known as "penicilina" and "terramicina", Alternanthera brasiliana (L.) Kuntze belongs to the Amaranthaceae family and stands out for its ethnomedicinal uses in the treatment of infections caused by pathogenic microorganisms in some countries.

AIM OF THE STUDY

The present study aimed to carry out a literature review and analyze whether the scientific evidence really validates the numerous indications for the use of A. brasiliana in traditional medicine for the treatment of infectious diseases. Phytochemical and toxicological studies related to this species were also analyzed.

MATERIAL AND METHODS

Scientific documents were retrieved from Google Scholar, PubMed®, ScienceDirect®, SciELO, SpringerLink®, Scopus®, and Web of Science™ databases. The literature was reviewed from the first report on the antimicrobial activity of A. brasiliana in 1994 until April 2024.

RESULTS

According to the scientific documents analyzed, it was observed that A. brasiliana is widely used as a natural antibiotic for the treatment of infectious diseases in Brazil, mainly in the states of Rio Grande do Sul, Mato Grosso, and Minas Gerais. Its ethnomedicinal uses have also been reported in other countries such as Colombia and India. The leaves (78%) of A. brasiliana are the main parts used in the preparation of herbal medicines by traditional communities. Several A. brasiliana extracts showed low activity when evaluated against pathogens, including gram-positive bacteria, gram-negative bacteria, parasitic protozoa, and fungi. Only two studies reported that extracts from this plant showed high activity against the herpes simplex virus, Mycobacterium smegmatis, and Candida albicans. Phytochemicals belonging to the classes of phenolic compounds and flavonoid (52%), saturated and unsaturated fatty acids (33%), steroids and phytosterols (8%), terpenoids (5%), and fatty alcohol esters (2%) were identified in A. brasiliana. Toxicity (in vivo) and cytotoxicity (in vitro) studies of polar and non-polar extracts obtained from A. brasiliana leaves indicated that this plant is biologically safe.

CONCLUSION

Despite being widely used as a natural antibiotic by traditional communities, scientific investigations related to the antimicrobial potential of A. brasiliana extracts have indicated inactivity against several pathogens.

Framework Nucleic Acids Loaded with Quercetin: Protecting Retinal Neurovascular Unit via the Protein Kinase B/Heme Oxygenase-1 Pathway

Retinal neovascular disease is a leading cause of vision loss and blindness globally. It occurs when abnormal new blood vessels form in the retina. In this study, we utilized tetrahedral framework nucleic acids (tFNAs) as vehicles to load quercetin (QUE), a small-molecule flavonoid, forming a deoxyribonucleic acid (DNA) nanocomplex, tFNAs-QUE. Our data show this nanocomplex inhibits pathological neovascularization, reduces the area of retinal nonperfusion area, protects retinal neurons, and preserves the visual function. Further, we discovered that tFNAs-QUE selectively upregulates the AKT/Nrf2/HO-1 signaling pathway, which can suppress pathological vascular growth and exert antioxidative effects. Therefore, this study presents a promising small-molecule-loading mechanism for the treatment of ischemic retinal diseases.

Exploration of the potential mechanism of Yiyi Tongfeng Formula in the treatment of acute gouty arthritis based on network pharmacology and molecular docking: A review

The global prevalence of gout is on the rise. Yiyi Tongfeng Formula (YTF), a traditional herbal compound, has gained recognition for its efficacy in managing acute gouty arthritis (AGA). Despite its widespread use, the underlying mechanisms of YTF in AGA treatment remain largely undefined. This study employed network pharmacology and molecular docking to elucidate these mechanisms. We utilized the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, SymMap database, and various literature sources to identify active components and corresponding targets of YTF. Relevant AGA-associated targets were identified through the Genecards, Drugbank, Therapeutic Target Database, and Online Mendelian Inheritance in Man databases. A protein-protein interaction network was constructed to delineate interactions between YTF targets and AGA. Key ingredients and central targets were further analyzed using Cytoscape. Functional enrichment analyses, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, were conducted via Metascape. Additionally, molecular docking studies were performed using PyMOL and AutoDock4. It was found that quercetin, kaempferol, and luteolin may be the main active components of YTF for AGA treatment. Gene Ontology enrichment analysis shows that the main biological processes involved are cellular responses to lipids, and inflammatory responses. Kyoto Encyclopedia of Genes and Genomes enrichment analysis suggests the involvement of the IL-17 signaling pathway, AGE-RAGE signaling pathway in diabetic complications, TNF signaling pathway, and so on. The findings suggest a multi-faceted therapeutic approach of YTF in treating AGA, involving multiple components, targets, biological processes, and signaling pathways. This comprehensive mechanism offers a foundation for further experimental validation.

Novel Insights into the Biological Activity of Croton lechleri Twigs Extracts and Advancements in Their Sustainable Recovery

Sangre de drago, the sap of Croton lechleri Müll. Arg. tree, has been used for centuries in traditional medicine owing to its diverse biological activities. Extracts derived from different parts of the species contain a multitude of phytochemicals with varied applications. Twigs, however, are among the least studied parts of the plant. This study unveils new biological activities of Croton lechleri twig extracts recovered by applying Soxhlet and advanced green techniques. For all extracts, total phenolic content and antioxidant activity were determined. Subsequently, four were selected, and their cytotoxic effects were assessed on both normal (HaCat) and malignant melanoma (A375) skin cell lines using the MTT assay and trypan blue exclusion assay. All showed dose-dependent cytotoxicity, with the Soxhlet ethanol extract demonstrating the highest selectivity towards A375 cells over HaCat cells. The extracts induced apoptosis and necrosis, as confirmed by Annexin V/PI dual-labeling and flow cytometry, highlighting their ability to trigger programmed cell death in cancer cells. The selective inhibition of cell cycle progression in A375 compared to HaCat observed both for Soxhlet ethanol and pressurized ethanol extracts induces cell cycle arrest at multiple points, primarily in the G1 and G2/M phases, and significantly reduces DNA synthesis as evidenced by the decrease in the S-phase population, confirmed by the EdU assay. Consequently, the Soxhlet extract composition was analyzed using LC-MS, which revealed their richness in polyphenolic compounds, particularly flavonoids from the flavonol subclass.

Zishenhuoxue decoction-induced myocardial protection against ischemic injury through TMBIM6-VDAC1-mediated regulation of calcium homeostasis and mitochondrial quality surveillance

BACKGROUND

Zishenhuoxue decoction (ZSHX), a Chinese herbal medicine, exhibits myocardial and vascular endothelial protective properties. The intricate regulatory mechanisms underlying myocardial ischemic injury and its association with dysfunctional mitochondrial quality surveillance (MQS) remain elusive.

HYPOTHESIS/PURPOSE

To study the protective effect of ZSHX on ischemic myocardial injury in mice using a TMBIM6 gene-modified animal model and mitochondrial quality control-related experiments.

STUDY DESIGN

Using model animals and myocardial infarction surgery-induced ischemic myocardial injury TMBIM6 gene-modified mouse models, the pharmacological activity of ZSHX in inhibiting ischemic myocardial injury and mitochondrial homeostasis disorder in vivo was tested.

METHODS

Our focal point entailed scrutinizing the impact of ZSHX on ischemic myocardial impairment through the prism of TMBIM6. This endeavor was undertaken utilizing mice characterized by heart-specific TMBIM6 knockout (TMBIM6CKO) and their counterparts, the TMBIM6 transgenic (TMBIM6TG) and VDAC1 transgenic (VDAC1TG) mice.

RESULTS

ZSHX demonstrated dose-dependent effectiveness in mitigating ischemic myocardial injury and enhancing mitochondrial integrity. TMBIM6CKO hindered ZSHX's cardio-therapeutic and mitochondrial protective effects, while ZSHX's benefits persisted in TMBIM6TG mice. TMBIM6CKO also blocked ZSHX's regulation of mitochondrial function in HR-treated cardiomyocytes. Hypoxia disrupted the MQS in cardiomyocytes, including calcium overload, excessive fission, mitophagy issues, and disrupted biosynthesis. ZSHX counteracted these effects, thereby normalizing MQS and inhibiting calcium overload and cardiomyocyte necroptosis. Our results also showed that hypoxia-induced TMBIM6 blockade resulted in the over-activation of VDAC1, a major mitochondrial calcium uptake pathway, while ZSHX could increase the expression of TMBIM6 and inhibit VDAC1-mediated calcium overload and MQS abnormalities.

CONCLUSIONS

Our findings suggest that ZSHX regulates mitochondrial calcium homeostasis and MQS abnormalities through a TMBIM6-VDAC1 interaction mechanism, which helps to treat ischemic myocardial injury and provides myocardial protection. This study also offers insights for the clinical translation and application of mitochondrial-targeted drugs in cardiomyocytess.

Quercetin Attenuates Acetaldehyde-Induced Cytotoxicity via the Heme Oxygenase-1-Dependent Antioxidant Mechanism in Hepatocytes

It is still unclear whether or how quercetin influences the toxic events induced by acetaldehyde in hepatocytes, though quercetin has been reported to mitigate alcohol-induced mouse liver injury. In this study, we evaluated the modulating effect of quercetin on the cytotoxicity induced by acetaldehyde in mouse hepatoma Hepa1c1c7 cells, the frequently used cellular hepatocyte model. The pretreatment with quercetin significantly inhibited the cytotoxicity induced by acetaldehyde. The treatment with quercetin itself had an ability to enhance the total ALDH activity, as well as the ALDH1A1 and ALDH3A1 gene expressions. The acetaldehyde treatment significantly enhanced the intracellular reactive oxygen species (ROS) level, whereas the quercetin pretreatment dose-dependently inhibited it. Accordingly, the treatment with quercetin itself significantly up-regulated the representative intracellular antioxidant-related gene expressions, including heme oxygenase-1 (HO-1), glutamate-cysteine ligase, catalytic subunit (GCLC), and cystine/glutamate exchanger (xCT), that coincided with the enhancement of the total intracellular glutathione (GSH) level. Tin protoporphyrin IX (SNPP), a typical HO-1 inhibitor, restored the quercetin-induced reduction in the intracellular ROS level, whereas buthionine sulphoximine, a representative GSH biosynthesis inhibitor, did not. SNPP also cancelled the quercetin-induced cytoprotection against acetaldehyde. These results suggest that the low-molecular-weight antioxidants produced by the HO-1 enzymatic reaction are mainly attributable to quercetin-induced cytoprotection.

10-Eicosanol Alleviates Patulin-Induced Cell Cycle Arrest and Apoptosis by Activating AKT (Protein Kinase B) in Porcine Intestinal Epithelial Cells

Patulin (PAT) is a fungal toxin prevalent in apples and apple products and associated with several toxic effects, potentially harming multiple organs, including the kidneys, liver, and colon. However, the precise molecular mechanism through which PAT affects the intestines remains comprehensively unclear. Therefore, this study aims to investigate the molecular effects of PAT on the intestinal epithelium. Gene expression profiling was conducted, hypothesizing that PAT induces cell cycle arrest and apoptosis through the PI3K-Akt signaling pathway. Cell cycle analysis, along with Annexin-V and propidium iodide staining, confirmed that PAT induced G2/M phase arrest and apoptosis in IPEC-J2 cells. Additionally, PAT activated the expression of cell cycle-related genes (CDK1, CCNB1) and apoptosis-related genes (BCL6, CASP9). Treatment with SC79, an AKT activator, mitigated cell cycle arrest and apoptosis. To identify natural products that could mitigate the harmful effects of PAT in small intestinal epithelial cells in pigs, the high-throughput screening of a natural product library was conducted, revealing 10-Eicosanol as a promising candidate. In conclusion, our study demonstrates that 10-Eicosanol alleviates PAT-induced cell cycle arrest and apoptosis in IPEC-J2 cells by activating AKT.

COVID-19-Associated Sepsis: Potential Role of Phytochemicals as Functional Foods and Nutraceuticals

The acute manifestations of coronavirus disease 2019 (COVID-19) exhibit the hallmarks of sepsis-associated complications that reflect multiple organ failure. The inflammatory cytokine storm accompanied by an imbalance in the pro-inflammatory and anti-inflammatory host response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection leads to severe and critical septic shock. The sepsis signature in severely afflicted COVID-19 patients includes cellular reprogramming and organ dysfunction that leads to high mortality rates, emphasizing the importance of improved clinical care and advanced therapeutic interventions for sepsis associated with COVID-19. Phytochemicals of functional foods and nutraceutical importance have an incredible impact on the healthcare system, which includes the prevention and/or treatment of chronic diseases. Hence, in the present review, we aim to explore the pathogenesis of sepsis associated with COVID-19 that disrupts the physiological homeostasis of the body, resulting in severe organ damage. Furthermore, we have summarized the diverse pharmacological properties of some potent phytochemicals, which can be used as functional foods as well as nutraceuticals against sepsis-associated complications of SARS-CoV-2 infection. The phytochemicals explored in this article include quercetin, curcumin, luteolin, apigenin, resveratrol, and naringenin, which are the major phytoconstituents of our daily food intake. We have compiled the findings from various studies, including clinical trials in humans, to explore more into the therapeutic potential of each phytochemical against sepsis and COVID-19, which highlights their possible importance in sepsis-associated COVID-19 pathogenesis. We conclude that our review will open a new research avenue for exploring phytochemical-derived therapeutic agents for preventing or treating the life-threatening complications of sepsis associated with COVID-19.

New Perspectives about Relevant Natural Compounds for Current Dentistry Research

Natural compounds have been used since the earliest civilizations and remain, to this day, a safer alternative for treating various dental problems. These present antimicrobial, anti-inflammatory, antioxidant, analgesic, and antimutagenic effects, making them useful in the prophylactic and curative treatment of various oral diseases such as infections, gingivitis, periodontitis, and even cancer. Due to the high incidence of unpleasant adverse reactions to synthetic compounds, natural products tend to gradually replace conventional treatment, as they can be just as potent and cause fewer, milder adverse effects. Researchers use several methods to measure the effectiveness and safety profile of these compounds, and employing standard techniques also contributes to progress across all medical disciplines.

Polyphenols targeting multiple molecular targets and pathways for the treatment of vitiligo

Vitiligo, a pigmentary autoimmune disorder, is marked by the selective loss of melanocytes in the skin, leading to the appearance of depigmented patches. The principal pathological mechanism is the melanocyte destruction mediated by CD8+ T cells, modulated by oxidative stress and immune dysregulation. Vitiligo affects both physical health and psychological well-being, diminishing the quality of life. Polyphenols, naturally occurring compounds with diverse pharmacological properties, including antioxidant and anti-inflammatory activities, have demonstrated efficacy in managing various dermatological conditions through multiple pathways. This review provides a comprehensive analysis of vitiligo and the therapeutic potential of natural polyphenolic compounds. We examine the roles of various polyphenols in vitiligo management through antioxidant and immunomodulatory effects, melanogenesis promotion, and apoptosis reduction. The review underscores the need for further investigation into the precise molecular mechanisms of these compounds in vitiligo treatment and the exploration of their combination with current therapies to augment therapeutic outcomes.

Plant-derived bioactive compounds and their novel role in central nervous system disorder treatment via ATF4 targeting: A systematic literature review

Central nervous system (CNS) disorders exhibit exceedingly intricate pathogenic mechanisms. Pragmatic and effective solutions remain elusive, significantly compromising human life and health. Activating transcription factor 4 (ATF4) participates in the regulation of multiple pathophysiological processes, including CNS disorders. Considering the widespread involvement of ATF4 in the pathological process of CNS disorders, the targeted regulation of ATF4 by plant-derived bioactive compounds (PDBCs) may become a viable strategy for the treatment of CNS disorders. However, the regulatory relationship between PDBCs and ATF4 remains incompletely understood. Here, we aimed to comprehensively review the studies on PDBCs targeting ATF4 to ameliorate CNS disorders, thereby offering novel directions and insights for the treatment of CNS disorders. A computerized search was conducted on PubMed, Embase, Web of Science, and Google Scholar databases to identify preclinical experiments related to PDBCs targeting ATF4 for the treatment of CNS disorders. The search timeframe was from the inception of the databases to December 2023. Two assessors conducted searches using the keywords "ATF4," "Central Nervous System," "Neurological," "Alzheimer's disease," "Parkinson's Disease," "Stroke," "Spinal Cord Injury," "Glioblastoma," "Traumatic Brain Injury," and "Spinal Cord Injury." Overall, 31 studies were included, encompassing assessments of 27 PDBCs. Combining results from in vivo and in vitro studies, we observed that these PDBCs, via ATF4 modulation, prevent the deposition of amyloid-like fibers such as Aβ, tau, and α-synuclein. They regulate ERS, reduce the release of inflammatory factors, restore mitochondrial membrane integrity to prevent oxidative stress, regulate synaptic plasticity, modulate autophagy, and engage anti-apoptotic mechanisms. Consequently, they exert neuroprotective effects in CNS disorders. Numerous PDBCs targeting ATF4 have shown potential in facilitating the restoration of CNS functionality, thereby presenting expansive prospects for the treatment of such disorders. However, future endeavors necessitate high-quality, large-scale, and comprehensive preclinical and clinical studies to further validate this therapeutic potential.

Quercetin as one of the most abundant represented biological valuable plant components with remarkable chemoprotective effects - A review

As a consequence of environmental quality changes as well as changes in our population's lifestyle, there is rapidly increasing variability and many so-called lifestyle disorders, allergies, and food intolerances (also known as non-allergic food hypersensitivity). Unhealthy eating practices, an inappropriate food composition with an excessive energy intake, a high intake of saturated fats, simple sugars, and salt, as well as an inadequate intake of fibre, vitamins, and substances with preventive effects (such as antioxidants), are some of the factors causing this detrimental phenomenon. Enhanced consumption of plant foods rich in valuable secondary metabolites such as phenolic acids and flavonoids with the benefit on human health, food research focused on these components, and production of foods with declared higher content of biologically active and prophylactic substances are some ways how to change and improve this situation. A unique class of hydroxylated phenolic compounds with an aromatic ring structure are called flavonoids. One unique subclass of flavonoids is quercetin. This phytochemical naturally takes place in fruits, vegetables, herbs, and other plants. Quercetin and its several derivates are considered to be promising substances with significant antidiabetic, antibacterial, anti-inflammatory, and antioxidant effects, which could also act preventively against cardiovascular disease, cancer, or Alzheimer's disease.

MeNPs-PEDOT Composite-Based Detection Platforms for Epinephrine and Quercetin

The development of low-cost, sensitive, and simple analytical tools for biomolecule detection in health status monitoring is nowadays a growing research topic. Sensing platforms integrating nanocomposite materials as recognition elements in the monitoring of various biomolecules and biomarkers are addressing this challenging objective. Herein, we have developed electrochemical sensing platforms by means of a novel fabrication procedure for biomolecule detection. The platforms are based on commercially available low-cost conductive substrates like glassy carbon and/or screen-printed carbon electrodes selectively functionalized with nanocomposite materials composed of Ag and Au metallic nanoparticles and an organic polymer, poly(3,4-ethylenedioxythiophene). The novel fabrication method made use of alternating currents with controlled amplitude and frequency. The frequency of the applied alternating current was 100 mHz for the polymer deposition, while a frequency value of 50 mHz was used for the in situ electrodeposition of Ag and Au nanoparticles. The selected frequency values ensured the successful preparation of the composite materials. The use of readily available composite materials is intended to produce cost-effective analytical tools. The judicious modification of the organic conductive matrix by various metallic nanoparticles, such as Ag and Au, extends the potential applications of the sensing platform toward a range of biomolecules like quercetin and epinephrine, chosen as benchmark analytes for proof-of-concept antioxidant and neurotransmitter detection. The sensing platforms were tested successfully for quercetin and epinephrine determination on synthetic and real samples. Wide linear response ranges and low limit-of-detection values were obtained for epinephrine and quercetin detection.

Study on the mechanism of inhibition of Escherichia coli by Polygonum capitatum based on network pharmacology and molecular docking technology: A review

This study aims to analyze the effective components of Polygonum capitatum (PC) inhibiting Escherichia coli based on network pharmacology methods and predict its molecular mechanism of action. PC compounds and targets were collected from the TCMSP database, Swiss Target Prediction, and the literature. E coli targets were searched using the GeneCards database. The targets of E coli and the targets of the active ingredients of PC were taken as intersections to obtain the intersecting targets. The resulting overlapping targets were uploaded to the STRING database to construct the protein interaction network diagram of E coli target inhibition. The key targets for the inhibitory effect of PC on E coli were obtained. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed by uploading key targets into the DAVID database. The results showed that there were 50 targets for PC to inhibit E coli. Among them, there are 5 core targets, mainly including AKT1, TNF, EGFR, JUN, and ESR1. A total of 196 gene ontology functional analysis results and 126 Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis results were obtained. These include cellular response to cadmium-ion, cellular response to reactive oxygen species, pathways in cancer, prostate cancer, and PI3K-Akt signaling pathway. Molecular docking results indicate that Lutedin, Hirsutin, Flazin, and Ellagic acid in PC have high affinity for the target genes AKT1, TNF, MAPK3 and EGFR. PC exerts its inhibitory effect on E coli through multi-targets and multi-pathways, which provides a new basis for the new use of PC as an old medicine.

Therapeutic potential activity of quercetin complexes against Streptococcus pneumoniae

This study investigates quercetin complexes as potential synergistic agents against the important respiratory pathogen Streptococcus pneumoniae. Six quercetin complexes (QCX1-6) were synthesized by reacting quercetin with various metal salts and boronic acids and characterized using FTIR spectroscopy. Their antibacterial activity alone and in synergism with antibiotics was evaluated against S. pneumoniae ATCC 49619 using disc diffusion screening, broth microdilution MIC determination, and checkerboard assays. Complexes QCX-3 and QCX-4 demonstrated synergy when combined with levofloxacin via fractional inhibitory concentration indices ≤ 0.5 as confirmed by time-kill kinetics. Molecular docking elucidated interactions of these combinations with virulence enzymes sortase A and sialidase. A biofilm inhibition assay found the synergistic combinations more potently reduced biofilm formation versus monotherapy. Additionally, gene-gene interaction networks, biological activity predictions and in-silico toxicity profiling provided insights into potential mechanisms of action and safety.

Recent advances in reactive oxygen species scavenging nanomaterials for wound healing

Reactive oxygen species play a crucial role in cell signaling pathways during wound healing phases. Treatment strategies to balance the redox level in the deep wound tissue are emerging for wound management. In recent years, reactive oxygen species scavenging agents including natural antioxidants, reactive oxygen species (ROS) scavenging nanozymes, and antioxidant delivery systems have been widely employed to inhibit oxidative stress and promote skin regeneration. Here, the importance of reactive oxygen species in different wound healing phases is critically analyzed. Various cutting-edge bioactive ROS nanoscavengers and antioxidant delivery platforms are discussed. This review also highlights the future directions for wound therapies via reactive oxygen species scavenging. This comprehensive review offers a map of the research on ROS scavengers with redox balancing mechanisms of action in the wound healing process, which benefits development and clinical applications of next-generation ROS scavenging-based nanomaterials in skin regeneration.

Mini-encyclopedia of mitochondria-relevant nutraceuticals protecting health in primary and secondary care-clinically relevant 3PM innovation

Despite their subordination in humans, to a great extent, mitochondria maintain their independent status but tightly cooperate with the "host" on protecting the joint life quality and minimizing health risks. Under oxidative stress conditions, healthy mitochondria promptly increase mitophagy level to remove damaged "fellows" rejuvenating the mitochondrial population and sending fragments of mtDNA as SOS signals to all systems in the human body. As long as metabolic pathways are under systemic control and well-concerted together, adaptive mechanisms become triggered increasing systemic protection, activating antioxidant defense and repair machinery. Contextually, all attributes of mitochondrial patho-/physiology are instrumental for predictive medical approach and cost-effective treatments tailored to individualized patient profiles in primary (to protect vulnerable individuals again the health-to-disease transition) and secondary (to protect affected individuals again disease progression) care. Nutraceuticals are naturally occurring bioactive compounds demonstrating health-promoting, illness-preventing, and other health-related benefits. Keeping in mind health-promoting properties of nutraceuticals along with their great therapeutic potential and safety profile, there is a permanently growing demand on the application of mitochondria-relevant nutraceuticals. Application of nutraceuticals is beneficial only if meeting needs at individual level. Therefore, health risk assessment and creation of individualized patient profiles are of pivotal importance followed by adapted nutraceutical sets meeting individual needs. Based on the scientific evidence available for mitochondria-relevant nutraceuticals, this article presents examples of frequent medical conditions, which require protective measures targeted on mitochondria as a holistic approach following advanced concepts of predictive, preventive, and personalized medicine (PPPM/3PM) in primary and secondary care.

Using network pharmacology and molecular docking to uncover the mechanism by which quercetin alleviates deoxynivalenol-induced porcine intestinal injury

Deoxynivalenol is a widespread feed contaminant that leads to vomit, which results in serious symptom such as increased intestinal permeability and even intestinal mucosal necrosis. Recent studies have reported the role of quercetin in alleviating deoxynivalenol-induced intestinal injury; however, the mechanisms and targets remain unclear. Thus, we aimed to identify the mechanisms of action by using a combination of network pharmacology and molecular docking. We identified 151 quercetin targets, 235 deoxynivalenol targets and 47 porcine intestinal injury targets by searching compound database and PubMed database, among which there were two common targets. The PPI network showed that the key proteins involved are NQO1 and PPAR-γ. The PPI network showed that the key proteins involved were NQO1 and PPARG. GO analysis found that genes were enriched primarily in response to oxidative stress. The PPI network showed that the key proteins involved are NQO1 and PPAR-γ. The genes are enriched primarily in response to oxidative stress. KEGG analysis showed enrichment of the HIF, reactive oxygen species and other signaling pathways. The molecular docking results indicated key binding activity between NQO1-quercetin and PPAR-γ-quercetin. By using network pharmacology, we have revealed the potential molecular mechanisms by which quercetin alleviates deoxynivalenol-induced porcine intestinal injury, which lays the foundation for the development of drugs to treat deoxynivalenol-induced intestinal injury in pigs.

Opportunities, Challenges, and Scientific Progress in Hemp Crops

The resurgence of cannabis (Cannabis sativa L.) has been propelled by changes in the legal framework governing its cultivation and use, increased demand for hemp-derived products, and studies recognizing the industrial and health benefits of hemp. This has led to the creation of novel high-cannabidiol, low-Δ9-tetrahydrocannabinol varieties, enabling hemp crop expansion worldwide. This review elucidates the recent implications for hemp cultivation in Europe, with a focus on the legislative impacts on the cultivation practices, prospective breeding efforts, and dynamic scientific landscape surrounding this crop. We also review the current cultivars' cannabinoid composition of the European hemp market and its major differences with that of the United States.

Integrated Metabolomic and Transcriptomic Analysis Reveals the Underlying Antibacterial Mechanisms of the Phytonutrient Quercetin-Induced Fatty Acids Alteration in Staphylococcus aureus ATCC 27217

The utilization of natural products in food preservation represents a promising strategy for the dual benefits of controlling foodborne pathogens and enhancing the nutritional properties of foods. Among the phytonutrients, flavonoids have been shown to exert antibacterial effects by disrupting bacterial cell membrane functionality; however, the underlying molecular mechanisms remain elusive. In this study, we investigated the effect of quercetin on the cell membrane permeability of Staphylococcus aureus ATCC 27217. A combined metabolomic and transcriptomic approach was adopted to examine the regulatory mechanism of quercetin with respect to the fatty acid composition and associated genes. Kinetic analysis and molecular docking simulations were conducted to assess quercetin's inhibition of β-ketoacyl-acyl carrier protein reductase (FabG), a potential target in the bacterial fatty acid biosynthesis pathway. Metabolomic and transcriptomic results showed that quercetin increased the ratio of unsaturated to saturated fatty acids and the levels of membrane phospholipids. The bacteria reacted to quercetin-induced stress by attempting to enhance fatty acid biosynthesis; however, quercetin directly inhibited FabG activity, thereby disrupting bacterial fatty acid biosynthesis. These findings provide new insights into the mechanism of quercetin's effects on bacterial cell membranes and suggest potential applications for quercetin in bacterial inhibition.

Exploring the Mechanism of Yiwei Decoction in the Intervention of a Premature Ovarian Insufficiency Rat Based on Network Pharmacology and the miRNA-mRNA Regulatory Network

OBJECTIVE

our aim is to explore the mechanism of action of Yiwei decoction (YWD) in addressing premature ovarian insufficiency (POI) through a combination of transcriptomics and network pharmacology. By doing so, we hope to identify important pathways of action, key targets, and active components that contribute to the efficacy of YWD.

MATERIALS AND METHODS

group A comprised of the model + traditional Chinese medicine group, while group B was the model control group and group C was the normal control group. After gavage, serum AMH and E2 levels were measured by using ELISA. HE staining was used to study the impact of YWD on ovarian follicle recovery in POI rats. Additionally, RNA-seq sequencing technology was employed to analyze the transcription levels of mRNAs and miRNAs in the ovarian tissues of each group, and the resulting data were examined using R. YWD used UPLC-Q-TOF-HRMS to analyze its active ingredients. Upon obtaining the sequencing results, the miRWalk database was utilized to forecast the targets of DEmiRNAs. Network pharmacology was then applied to predict the targets of active ingredients present in YWD, ultimately constructing a regulatory network consisting of active ingredients-mRNA-miRNA. The coexpression relationship between mRNAs and miRNAs was calculated using the Pearson correlation coefficient, and high correlation coefficients between miRNA-mRNA were confirmed through miRanda sequence combination.

RESULTS

the application of YWD resulted in improved serum levels of AMH and E2, as well as an increased number of ovarian follicles in rats with POI. However, there was a minimal impact on the infiltration of ovarian lymphocytes. Through GSEA pathway enrichment analysis, we found that YWD may have a regulatory effect on PI3K-Akt, ovarian steroidogenesis, and protein digestion and absorption, which could aid in the treatment of POI. Additionally, our research discovered a total of 6 DEmiRNAs between groups A and B, including 2 new DEmiRNAs. YWD contains 111 active compounds, and our analysis of the active component-mRNA regulatory network revealed 27 active components and 73 mRNAs. Furthermore, the coexpression network included 5 miRNAs and 18 mRNAs. Our verification of MiRanda binding demonstrated that 12 of the sequence binding sites were stable.

CONCLUSIONS

our research has uncovered the regulatory network mechanism of active ingredients, mRNA, and miRNA in YWD POI treatment. However, further research is needed to determine the effect of the active ingredients on key miRNAs and mRNAs.

Cuscuta chinensis flavonoids alleviate ovarian damage in offspring female mice induced by BPA exposure during pregnancy by regulating the central carbon metabolism pathway

Pregnancy is a sensitive window period for bisphenol A (BPA) exposure. BPA can pass through the placenta and cause reproductive damage in offspring female mice. Even BPA that is not metabolized during lactation can be passed through milk. Cuscuta chinensis flavonoids (CCFs) can alleviate reproductive damage caused by BPA, but the mechanism of action is unclear. To investigate the potential mitigating impact of CCFs on ovarian damage resulting from BPA exposure during pregnancy, we administered BPA and CCFs to pregnant mice during the gestational period spanning from 0.5 to 17.5 days. Aseptic collection of serum and ovaries from female mice was conducted on postnatal day 21 (PND21). Serum hormone levels and tissue receptor levels were quantified utilizing ELISA and PCR, while ovaries underwent sequencing and analysis through transcriptomics and metabolomics techniques. Additionally, the assessment of ovarian oxidative stress levels was carried out as part of the comprehensive analysis. The results showed that CCFs administration mitigated the adverse effects induced by BPA exposure on ovarian index, hormone levels, receptor expression, and mRNA expression levels in female offspring mice. The joint analysis of transcriptome and metabolome revealed 48 enriched pathways in positive ion mode and 44 enriched pathways in negative ion mode. Among them, the central carbon metabolism pathway is significantly regulated by BPA and CCFs. The screened sequencing results were verified through qPCR and biochemical kits. In this study, CCFs may participate in the central carbon metabolism pathway by reducing the expression of Kit proto-oncogene (Kit), hexokinase 1 gene (Hk1) and pyruvate kinase M (Pkm) mRNA and increasing the expression of h-ras proto-oncogene (Hras), sirtuin 3 (Sirt3), sirtuin 6 (Sirt6) and TP53 induced glycolysis regulatory phosphatase gene (Tigar) mRNA, thereby resisting the effects of BPA on the body. At the same time, the metabolic levels of D-Fructose 1,6-bisphosphate and L-Asparagine tend to be stable. Moreover, CCFs demonstrated a capacity to diminish the BPA-induced escalation in reactive oxygen species (ROS) and malondialdehyde (MDA). Simultaneously, it exhibited the ability to elevate levels of glutathione (GSH) and catalase (CAT), thereby effectively preventing peroxidation. In summary, CCFs alleviate BPA-induced ovarian damage in offspring female mice by regulating the central carbon metabolism pathway. This study will improve the information on BPA reproductive damage antagonist drugs and provide a theoretical basis for protecting animal reproductive health.

Quercetin Regulates Lipid Metabolism and Fat Accumulation by Regulating Inflammatory Responses and Glycometabolism Pathways: A Review

Fat synthesis and lipolysis are natural processes in growth and have a close association with health. Fat provides energy, maintains physiological function, and so on, and thus plays a significant role in the body. However, excessive/abnormal fat accumulation leads to obesity and lipid metabolism disorder, which can have a detrimental impact on growth and even harm one's health. Aside from genetic effects, there are a range of factors related to obesity, such as excessive nutrient intake, inflammation, glycometabolism disease, and so on. These factors could serve as potential targets for anti-obesity therapy. Quercetin is a flavonol that has received a lot of attention recently because of its role in anti-obesity. It was thought to have the ability to regulate lipid metabolism and have a positive effect on anti-obesity, but the processes are still unknown. Recent studies have shown the role of quercetin in lipid metabolism might be related to its effects on inflammatory responses and glycometabolism. The references were chosen for this review with no date restrictions applied based on the topics they addressed, and the databases PubMed and Web of Sicence was used to conduct the references research, using the following search terms: "quercetin", "obesity", "inflammation", "glycometabolism", "insulin sensitivity", etc. This review summarizes the potential mechanisms of quercetin in alleviating lipid metabolism through anti-inflammatory and hypoglycemic signaling pathways, and describes the possible signaling pathways in the interaction of inflammation and glycometabolism, with the goal of providing references for future research and application of quercetin in the regulation of lipid metabolism.

Quercetin alleviates hyperoxia-induced bronchopulmonary dysplasia by inhibiting ferroptosis through the MAPK/PTGS2 pathway: Insights from network pharmacology, molecular docking, and experimental evaluations

Quercetin, a bioactive natural compound renowned for its potent anti-inflammatory, antioxidant, and antiviral properties, has exhibited therapeutic potential in various diseases. Given that bronchopulmonary dysplasia (BPD) development is closely linked to inflammation and oxidative stress, and quercetin, a robust antioxidant known to activate NRF2 and influence the ferroptosis pathway, offers promise for a wide range of age groups. Nonetheless, the specific role of quercetin in BPD remains largely unexplored. This study aims to uncover the target role of quercetin in BPD through a combination of network pharmacology, molecular docking, computer analyses, and experimental evaluations.

Investigating the in vitro antibacterial efficacy of composite bone cement incorporating natural product-based monomers and gentamicin

OBJECTIVE

The objective of this study is to investigate the impact of four natural product extracts, namely, aloe-emodin, quercetin, curcumin, and tannic acid, on the in vitro bacteriostatic properties and biocompatibility of gentamicin-loaded bone cement and to establish an experimental groundwork supporting the clinical utility of antibiotic-loaded bone cements (ALBC).

METHODS

Based on the components, the bone cement samples were categorized as follows: the gentamicin combined with aloe-emodin group, the gentamicin combined with quercetin group, the gentamicin combined with curcumin group, the gentamicin combined with tannic acid group, the gentamicin group, the aloe-emodin group, the quercetin group, the curcumin group, and the tannic acid group. Using the disk diffusion test, we investigated the antibacterial properties of the bone cement material against Staphylococcus aureus (n = 4). We tested cell toxicity and proliferation using the cell counting kit-8 (CCK-8) and examined the biocompatibility of bone cement materials.

RESULTS

The combination of gentamicin with the four natural product extracts resulted in significantly larger diameters of inhibition zones compared to gentamicin alone, and the difference was statistically significant (P < 0.05). Except for the groups containing tannic acid, cells in all other groups showed good proliferation across varying time intervals without displaying significant cytotoxicity (P < 0.05).

CONCLUSION

In this study, aloe-emodin, quercetin, curcumin, and tannic acid were capable of enhancing the in vitro antibacterial performance of gentamicin-loaded bone cement against S. aureus. While the groups containing tannic acid displayed moderate cytotoxicity in in vitro cell culture, all other groups showed no discernible cytotoxic effects.

Quercetin in the Prevention of Induced Periodontal Disease in Animal Models: A Systematic Review and Meta-Analysis

BACKGROUND

Periodontitis is an inflammatory condition initiated by oral bacteria and is associated with several systemic diseases. Quercetin is an anti-inflammatory and anti-bacterial poly-phenol present in various foods. The aim of this meta-analysis was the evaluation of the effects of quercetin administration in animal models of experimental periodontitis.

METHODS

A systematic search was performed in electronic databases using the following search terms: "periodontitis" or "periodontal disease" or "gingivitis" and "quercetin" or "cyanidanol" or "sophoretin" or "pentahydroxyflavone". In vivo preclinical animal models of experimental periodontal disease with a measurement of alveolar bone loss were included in the analysis. The risk of bias of the included studies was assessed using the SYRCLE tool.

RESULTS

The systematic search yielded 335 results. Five studies were included, four of them qualified for a meta-analysis. The meta-analysis showed that quercetin administration decreased alveolar bone loss (τ2 = 0.31, 1.88 mm 95%CI: 1.09, 2.67) in experimental periodontal disease animal models. However, the risk of bias assessment indicated that four SYRCLE domains had a high risk of bias.

CONCLUSIONS

Quercetin diminishes periodontal bone loss and prevents disease progression in animal models of experimental periodontal disease. Quercetin might facilitate periodontal tissue hemostasis by reducing senescent cells, decreasing oxidative stress via SIRT1-induced autophagy, limiting inflammation, and fostering an oral bacterial microenvironment of symbiotic microbiota associated with oral health. Future research will show whether and how the promising preclinical results can be translated into the clinical treatment of periodontal disease.

Carbopol 940-based hydrogels loading synergistic combination of quercetin and luteolin from the herb Euphorbia humifusa to promote Staphylococcus aureus infected wound healing

With the increasing prevalence of Staphylococcus aureus infections, rapid emergence of drug resistance and the slow healing of infected wounds, developing an efficient antibiotic-free multifunctional wound dressing for inhibiting S. aureus and simultaneously facilitating wound healing have become a huge challenge. Due to their excellent biocompatibility and biodegradability, some carbopol hydrogels based on plant extracts or purified compounds have already been applied in wound healing treatment. In China, Euphorbia humifusa Willd. (EuH) has been traditionally used as a medicine and food homologous medicine for the treatment of furuncles and carbuncles mainly caused by S. aureus infection. In an earlier study, EuH-originated flavonoids quercetin (QU) and luteolin (LU) could serve as a potential source for anti-S. aureus drug discovery when used in synergy. However, the in vivo effects of QU and LU on S. aureus-infected wound healing are still unknown. In this study, we found a series of Carbopol 940-based hydrogels loading QU and LU in combination could disinfect S. aureus and also could promote wound healing. In the full-thickness skin defect mouse model infected with S. aureus, the wound contraction ratio, bacterial burden, skin hyperplasia and inflammation score, as well as collagen deposition and blood vessels were then investigated. The results indicate that the optimized QL2 [QU (32 μg mL-1)-LU (8 μg mL-1)] hydrogel with biocompatibility significantly promoted S. aureus-infected wound healing through anti-infection, anti-inflammation, collagen deposition, and angiogenesis, revealing it as a promising alternative for infected wound repair.

Unlocking the Potential: Quercetin and Its Natural Derivatives as Promising Therapeutics for Sepsis

Sepsis is a syndrome of organ dysfunction caused by an uncontrolled inflammatory response, which can seriously endanger life. Currently, there is still a shortage of specific therapeutic drugs. Quercetin and its natural derivatives have received a lot of attention recently for their potential in treating sepsis. Here, we provide a comprehensive summary of the recent research progress on quercetin and its derivatives, with a focus on their specific mechanisms of antioxidation and anti-inflammation. To obtain the necessary information, we conducted a search in the PubMed, Web of Science, EBSCO, and Cochrane library databases using the keywords sepsis, anti-inflammatory, antioxidant, anti-infection, quercetin, and its natural derivatives to identify relevant research from 6315 articles published in the last five years. At present, quercetin and its 11 derivatives have been intensively studied. They primarily exert their antioxidation and anti-inflammation effects through the PI3K/AKT/NF-κB, Nrf2/ARE, and MAPK pathways. The feasibility of these compounds in experimental models and clinical application were also discussed. In conclusion, quercetin and its natural derivatives have good application potential in the treatment of sepsis.

Targeting oxidative stress with natural products: A novel strategy for esophageal cancer therapy

Esophageal cancer (ESC) is a malignant tumor that originates from the mucosal epithelium of the esophagus and is part of the digestive tract. Although the exact pathogenesis of ESC has not been fully elucidated, excessive oxidative stress is an important characteristic that leads to the development of many cancers. Abnormal expression of several proteins and transcription factors contributes to oxidative stress in ESCs, which alters the growth and proliferation of ESCs and promotes their metastasis. Natural compounds, including alkaloids, terpenes, polyphenols, and xanthine compounds, can inhibit reactive oxygen species production in ESCs. These compounds reduce oxidative stress levels and subsequently inhibit the occurrence and progression of ESC through the regulation of targets and pathways such as the cytokine interleukins 6 and 10, superoxide dismutase, the NF-+ACY-kappa+ADs-B/MAPK pathway, and the mammalian Nrf2/ARE target pathway. Thus, targeting tumor oxidative stress has become a key focus in anti-ESC therapy. This review discusses the potential of Natural products (NPs) for treating ESCs and summarizes the application prospects of oxidative stress as a new target for ESC treatment. The findings of this review provide a reference for drug development targeting ESCs. Nonetheless, further high-quality studies will be necessary to determine the clinical efficacy of these various NPs.

Hyaluronic acid/polyphenol sunscreens with broad-spectrum UV protection properties from tannic acid and quercetin

Currently, commercial sunscreens cause a number of biotoxicity and environmental issues, making it imperative to develop biocompatible alternatives. In this study, we aimed to develop an alternative sunscreen from two ecofriendly and biocompatible natural polyphenolic compounds, tannic acid (TA) and quercetin (Que). The sunscreen was prepared through a simple process using an oil-in-water emulsion as the medium and hyaluronic acid (HA) as the base polymer to improve biocompatibility. The HA/TA/Que. sunscreen prepared in this study exhibits 0 % transmittance in the UVB region and <15 % transmittance in the UVA region, resulting in excellent sun-protection properties (SPF 30). Remarkably, the as-prepared HA/TA/Que. sunscreen has a suitable viscosity and similar UV protection properties to those of commercial sunscreens. The HA/TA/Que. sunscreen also exhibits 90.4 % antioxidant activity against 2,2-diphenyl-1-picrylhydrazyl, demonstrating an ability to effectively capture reactive oxygen species that directly affect the skin. In addition, the cell viability was >90 % at a concentration of 50 μg/mL after 7 days, indicating excellent cytocompatibility. Owing to its various advantageous features, the HA/TA/Que. sunscreen with excellent sun protection properties and multiple functionalities is expected to resolve many environmental and biological issues caused by commercial sunscreens.

Insights in Electrochemical Determination of Quercetin in Peach Vinegar by the Hexagonal Platinum Nanocrystal

Peach vinegar is a popular condiment that is thought to have various health benefits. However, the low levels of quercetin and complex detection environment in peach vinegar make it difficult to detect using traditional methods. Electrochemical detection is a promising solution because it is sensitive, inexpensive, and provides real-time results. Herein, a hexagonal Pt nanocrystal was developed as an electrocatalyst for selective detection of quercetin in peach vinegar, and a comprehensive examination was given of the electrochemical characteristics of quercetin when applied to electrodes modified with platinum. The morphology and crystal properties of Pt nanocrystals were analyzed, and the Pt-modified electrode was found to exhibit strong electrocatalytic effects toward quercetin in peach vinegar with a high sensitivity of 58 μA μM-1. Furthermore, the investigation showcased exceptional specificity, consistency, sustained durability, and replicability of the Pt-modified electrode in identifying quercetin. The detection result of the Pt-modified electrode tested in three different peach vinegar samples demonstrated its practical utility in real-world applications. Overall, the findings of this study may have important implications for the development of more efficient and sensitive electrochemical sensors for the detection of quercetin and other analytes in vinegar.

Potential of Flavonoids as Promising Phytotherapeutic Agents to Combat Multidrug-Resistant Infections

BACKGROUND

Considering the limited number of current effective treatments, Multidrug- Resistant (MDR) illnesses have grown to be a serious concern to public health. It has become necessary to look for new antimicrobial drugs because of the emergence of resistance to numerous kinds of antibiotics. The use of flavonoids is one phytotherapeutic strategy that has been researched as a potential remedy for this issue. Secondary plant compounds called flavonoids have been found to have an antibacterial effect against resistant microorganisms.

OBJECTIVE

This review seeks to give readers a glimpse into contemporary studies on flavonoids' potential to fight MDR infections.

METHODS

A systematic search was conducted on electronic databases (PubMed, Scopus, and Google Scholar) using relevant keywords such as flavonoids, MDR infections, antimicrobial activity, and resistance microbes. Studies that investigated the antimicrobial activity of flavonoids against resistant microbes were included in this review.

RESULTS

Most research found that flavonoids have antibacterial efficacy against resistant microorganisms, and some also showed that they have synergistic benefits with traditional antibiotics. The flavonoids quercetin, kaempferol, apigenin, and luteolin were the most often investigated ones. According to research, flavonoids affect microbial gene expression, inhibit microbial enzymes, and disrupt the integrity of microbial cell membranes. Additionally, a few studies have noted the flavonoids' low toxicity and safety.

CONCLUSION

For the treatment of infections that are resistant to many drugs, flavonoids constitute a promising class of phytotherapeutic agents. To develop flavonoid-based treatment methods for treating MDR illnesses and assess the potential of flavonoids as adjuvants to conventional antimicrobial drugs, more study is required.

Chicoric acid ameliorates sepsis-induced cardiomyopathy via regulating macrophage metabolism reprogramming

BACKGROUND

Sepsis-related cardiac dysfunction is believed to be a primary cause of high morbidity and mortality. Metabolic reprogramming is closely linked to NLRP3 inflammasome activation and dysregulated glycolysis in activated macrophages, leading to inflammatory responses in septic cardiomyopathy. Succinate dehydrogenase (SDH) and succinate play critical roles in the progression of metabolic reprogramming in macrophages. Inhibition of SDH may be postulated as an effective strategy to attenuate macrophage activation and sepsis-induced cardiac injury.

PURPOSE

This investigation was designed to examine the role of potential compounds that target SDH in septic cardiomyopathy and the underlying mechanisms involved.

METHODS/RESULTS

From a small molecule pool containing about 179 phenolic compounds, we found that chicoric acid (CA) had the strongest ability to inhibit SDH activity in macrophages. Lipopolysaccharide (LPS) exposure stimulated SDH activity, succinate accumulation and superoxide anion production, promoted mitochondrial dysfunction, and induced the expression of hypoxia-inducible factor-1α (HIF-1α) in macrophages, while CA ameliorated these changes. CA pretreatment reduced glycolysis by elevating the NAD+/NADH ratio in activated macrophages. In addition, CA promoted the dissociation of K(lysine) acetyltransferase 2A (KAT2A) from α-tubulin, and thus reducing α-tubulin acetylation, a critical event in the assembly and activation of NLRP3 inflammasome. Overexpression of KAT2A neutralized the effects of CA, indicating that CA inactivated NLRP3 inflammasome in a specific manner that depended on KAT2A inhibition. Importantly, CA protected the heart against endotoxin insult and improved sepsis-induced cardiac mitochondrial structure and function disruption. Collectively, CA downregulated HIF-1α expression via SDH inactivation and glycolysis downregulation in macrophages, leading to NLRP3 inflammasome inactivation and the improvement of sepsis-induced myocardial injury.

CONCLUSION

These results highlight the therapeutic role of CA in the resolution of sepsis-induced cardiac inflammation.

Molecular dynamics, molecular docking, DFT, and ADMET investigations of the Co(II), Cu(II), and Zn(II) chelating on the antioxidant activity and SARS-CoV-2 main protease inhibition of quercetin

The natural flavonol quercetin (Q) is found in many vegetables, fruits, and beverages, and it is known as a strong antioxidant. Its metal ion chelation may increase its antioxidant activity. The present study aims to explore the Co(II), Cu(II), and Zn(II) chelating on the antioxidant effectiveness and severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) main protease (Mpro) inhibitory of quercetin using Density-functional theory (DFT), molecular docking, and molecular dynamics simulations (MD). DFT calculations at the B3LYP/LanL2DZ reveal that the high antioxidant activity of the metal-chelated quercetin complexes is mainly returned to their lower ionization potentials (IPs) compared with the one of the free quercetin. Molecular docking of quercetin and its Co(II), Cu(II), and Zn(II) chelates into the active binding sites of peroxiredoxin 5 and SARS-CoV-2 main protease (Mpro) were performed using Lamarckian Genetic Algorithm method. The docked quercetin and its metal chelates fit well into the binding site of the target proteins, and their binding affinity is strongly influenced by the type of the chelated metals Co(II), Cu(II), and Zn(II), and molar ratio metal: ligand, i.e. 1:2 and 2:1. Further, the binding stability of QZn2 and QCu2 in peroxiredoxin 5 and SARS-CoV-2 main protease targets is evaluated using MD simulation conducted for 100 ns simulations at natural room temperature conditions, and the obtained results showed that all chelates remain bound to the ligand binding groove of protein except for 1HD2_QZn2 complex. Finally, the adsorption, distribution, metabolism, excretion, and toxicity (ADMET) and drug-likeness properties of quercetin and cobalt(II)-quercetin (QCo2(II)) were investigated.Communicated by Ramaswamy H. Sarma.

Quercetin alleviates cadmium-induced BRL-3A cell apoptosis by inhibiting oxidative stress and the PERK/IRE1α/ATF6 signaling pathway

Cadmium (Cd) is a highly toxic environmental pollutant. The liver is an important metabolic organ in the body and is susceptible to Cd toxicity attacks. Quercetin (Que) is a flavonoid compound with pharmacological activities of scavenging free radicals and antioxidant activity. Previous studies have shown that Que can alleviate Cd caused hepatocyte apoptosis in rats, but the specific mechanism remains unclear. To explore the specific mechanism, we established a model of Cd toxicity and Que rescue in BRL-3A cells and used 4-phenylbutyrate (4-PBA), an endoplasmic reticulum stress (ERS) inhibitor, as positive control. Set up a control group, Cd treatment group, Cd and Que co treatment group, Que treatment group, Cd and 4-PBA co treatment group, and 4-PBA treatment group. Cell Counting Kit-8 (CCK-8) method was employed to measure cell viability. Fluorescence staining was applied to observe cell apoptosis. Flow cytometry was performed to detect reactive oxygen species levels. Real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot method was adopted to detect the mRNA and protein expression levels of ERS and apoptosis-related genes. The results showed that compared with the control group, the Cd treated group showed a significant decrease in cell viability (P < 0.01), an increase in intracellular ROS levels, and apoptosis. The mRNA and protein expression levels of ERS and apoptosis related factors such as GRP78, IRE1α, XBP1, ATF6, Caspase-12, Caspase-3 and Bax in the cells were significantly increased (P < 0.01), while the mRNA and protein expression levels of Bcl-2 were significantly reduced (P < 0.01). Compared with the Cd treatment group, the Cd and Que co treatment group and the Cd and 4-PBA co treatment group showed a significant increase in cell viability (P < 0.01), a decrease in intracellular ROS levels, a decrease in cell apoptosis, and a significant decrease in the expression levels of ERS and apoptosis related factors mRNA and protein (P < 0.01), as well as a significant increase in Bcl-2 mRNA and protein expression (P < 0.01). We confirmed that Que could alleviate the apoptosis caused by Cd in BRL-3A cells, and the effects of Que were similar to those of ERS inhibitor.

Quercetin suppresses ovariectomy-induced osteoporosis in rat mandibles by regulating autophagy and the NLRP3 pathway

With the aging population and the popularity of implant prostheses, an increasing number of postmenopausal osteoporosis (PMOP) patients require implant restorations; however, poor bone condition affects the long-term stability of implant prostheses. This study aimed to investigate the therapeutic effect of quercetin (QR) compared with alendronate (ALN), the primary treatment for PMOP, on mandibular osteoporosis (OP) induced by ovariectomy (OVX) in female rats. Adult female rats were treated with QR (50 mg/kg/day), ALN (6.25 mg/kg/week) by gavage for 8 weeks, chloroquine (CQ, 10 mg/kg/twice a week), and cytokine release inhibitory drug 3 (MCC950, 10 mg/kg/three times a week) by intraperitoneal injection for 8 weeks after bilateral OVX. Blood samples were collected prior to euthanasia; the mandibles were harvested and subjected to micro-computed tomography (micro-CT) and pathological analysis. QR administration controlled weight gain and significantly improved the bone microstructure in OVX rats, increasing bone mass, and bone mineral density (BMD), reducing bone trabecular spacing, and decreasing osteoclast numbers. Western blotting, real-time quantitative PCR (RT-qPCR), and serum markers confirmed that QR inhibited interleukin- 1β (IL-1β) and interleukin-18 (IL-18) on the nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) protein 3 (NLRP3) pathway thereby inhibiting osteoclast differentiation, immunofluorescence and western blotting also confirmed that QR inhibited autophagy in OVX rats and suppressed the number of tartrate-resistant acid phosphatase (TRAP)-stained positive osteoclasts. The findings suggest that QR may protect the bone structure and prevent bone loss in osteoporotic rats by inhibiting the NLRP3 pathway and autophagy in osteoclasts with comparable effects to ALN, thus QR may have the potential to be a promising alternative supplement for the preventive and therapeutic treatment of PMOP.

Synthesis of Quercetin-Loaded Silver Nanoparticles and Assessing Their Anti-Bacterial Potential

The study delves into the multifaceted potential of quercetin (Qu), a phytoconstituent found in various fruits, vegetables, and medicinal plants, in combination with silver nanoparticles (AgNPs). The research explores the synthesis and characterization of AgNPs loaded with Qu and investigates their pharmaceutical applications, particularly focusing on antibacterial properties. The study meticulously evaluates Qu's identity, and physicochemical properties, reaffirming its suitability for pharmaceutical use. The development of Qu-loaded AgNPs demonstrates their high drug entrapment efficiency, ideal particle characteristics, and controlled drug release kinetics, suggesting enhanced therapeutic efficacy and reduced side effects. Furthermore, the research examines the antibacterial activity of Qu in different solvents, revealing distinct outcomes. Qu, both in methanol and water formulations, exhibits antibacterial activity against Escherichia coli, with the methanol formulation displaying a slightly stronger efficacy. In conclusion, this study successfully synthesizes AgNPs loaded with Qu and highlights their potential as a potent antibacterial formulation. The findings underscore the influence of solvent choice on Qu's antibacterial properties and pave the way for further research and development in drug delivery systems and antimicrobial agents. This innovative approach holds promise for addressing microbial resistance and advancing pharmaceutical formulations for improved therapeutic outcomes.

Investigation of the combined cytotoxicity induced by sodium butyrate and a flavonoid quercetin treatment on MCF-7 breast cancer cells

Quercetin (QUE) belonging to the flavonoid class is a common phytochemical present in the daily diet of some individuals. Quercetin is an important source of free radical scavengers. This property makes this flavonoid a reliable antioxidant with the following properties: anti-inflammatory, anti-diabetic, antimicrobial and anti-carcinogenic. Sodium butyrate (NaBu) acts as a histone deacetylase inhibitor (HDACi) and is known to regulate apoptosis in cancer cells. Combining natural flavonoids such as QUE with different substances may synergistically enhance their anti-carcinogenic capacity. Thus, the aim of this study was to examine the combined treatment effects of QUE and NaBu in hormone-sensitive breast cancer cells in vitro. MCF-7 breast cancer cells were treated with QUE alone, NaBu alone, as well as QUE and NaBu combined to determine the following: cell proliferation, levels of protein annexin A5 (ANXA5) and reactive oxygen species (ROS), mRNA protein expression, as well as cell and nuclear morphology. Data demonstrated that either QUE or NaBu alone inhibited cell proliferation, and reduced levels protein ANXA5, ROS and mRNA protein expression, The combination of QUE and NaBu produced a significant synergistic inhibitory effect compared to treatment groups of QUE or NaBu alone. In conclusion, our findings showed that the combination treatment of QUE and NaBu may constitute a promising therapeutic approach to breast cancer treatment but this needs further molecular and in vivo investigations.

Quercetin and AMPK: A Dynamic Duo in Alleviating MG-Induced Inflammation via the AMPK/SIRT1/NF-κB Pathway

Mycoplasma gallisepticum (MG) is recognized as a principal causative agent of avian chronic respiratory disease, inflicting substantial economic losses upon the poultry industry. However, the extensive use of conventional antibiotics has resulted in the emergence of drug resistance and various challenges in their clinical application. Consequently, there is an urgent need to identify effective therapeutic agents for the prevention and treatment of mycoplasma-induced respiratory disease in avian species. AMP-activated protein kinase (AMPK) holds significant importance as a regulator of cellular energy metabolism and possesses the capacity to exert an anti-inflammatory effect by virtue of its downstream protein, SIRT1. This pathway has shown promise in counteracting the inflammatory responses triggered by pathogenic infections, thus providing a novel target for studying infectious inflammation. Quercetin possesses anti-inflammatory activity and has garnered attention as a potential alternative to antibiotics. However, there exists a gap in knowledge concerning the impact of this activation on MG-induced inflammatory damage. To address this knowledge gap, we employed AlphaFold2 prediction, molecular docking, and kinetic simulation methods to perform a systematic analysis. As expected, we found that both quercetin and the AMPK activator AICAR activate the chicken AMPKγ1 subunit in a similar manner, which was further validated at the cellular level. Our project aims to unravel the underlying mechanisms of quercetin's action as an agonist of AMPK against the inflammatory damage induced by MG infection. Accordingly, we evaluated the effects of quercetin on the prevention and treatment of air sac injury, lung morphology, immunohistochemistry, AMPK/SIRT1/NF-κB pathway activity, and inflammatory factors in MG-infected chickens. The results confirmed that quercetin effectively inhibits the secretion of pro-inflammatory cytokines such as IL-1β, TNF-α, and IL-6, leading to improved respiratory inflammation injury. Furthermore, quercetin was shown to enhance the levels of phosphorylated AMPK and SIRT1 while reducing the levels of phosphorylated P65 and pro-inflammatory factors. In conclusion, our study identifies the AMPK cascade signaling pathway as a novel cellular mediator responsible for quercetin's ability to counter MG-induced inflammatory damage. This finding highlights the potential significance of this pathway as an important target for anti-inflammatory drug research in the context of avian respiratory diseases.

Quercetin and its derivatives for wound healing in rats/mice: Evidence from animal studies and insight into molecular mechanisms

Aimed to clarify the effect of quercetin and its derivatives on wound healing in animal experiments. PubMed, Embase, Science Direct, Web of Science, SinoMed, Vip Journal Integration Platform, China National Knowledge Infrastructure and WanFang databases were searched for animal experiments investigating the effect of quercetin and its derivatives on wound healing to April 2023. The Review Manager 5.4 software was used to conduct meta-analysis. Eighteen studies were enrolled in this article. According to the SYRCLE's RoB tool assessment, these studies exposed relatively low methodological quality. It was shown that animals with cutaneous wound receiving quercetin had faster wound healing in wound closure (%) than the control group. Moreover, the difference in efficacy gradually emerged after third day (WMD = 7.13 [5.52, 8.74]), with a peak reached on the tenth day after wounding (WMD = 19.78 [17.82, 21.74]). Subgroup analysis revealed that quercetin for wound closure (%) was independent of the types of rats and mice, wound area and with or without diabetes. Clear conclusion was also shown regarding the external application of quercetin for wound healing (WMD = 17.77 [11.11, 24.43]). A significant reduction in the distribution of inflammatory cells occurred in the quercetin group. Quercetin could increase blood vessel density (WMD = 1.85 [0.68, -3.02]), fibroblast distribution and collagen fraction. Biochemical indicators, including IL-1β, IL-10, TNF-α, TGF-β, vascular endothelial growth factor (VEGF), hydroxyproline and alpha-smooth muscle actin (α-SMA), had the consistent results. Quercetin and its derivatives could promote the recovery of cutaneous wound in animals, through inhibiting inflammatory response and accelerating angiogenesis, proliferation of fibroblast and collagen deposition.