The Effect of Quercetin on Inflammatory Factors and Clinical Symptoms in Women with Rheumatoid Arthritis: A Double-Blind, Randomized Controlled Trial

Musculoskeletal imaging of senescence

Senescent cells play a vital role in the pathogenesis of musculoskeletal (MSK) diseases, such as chronic inflammatory joint disorders, rheumatoid arthritis (RA), and osteoarthritis (OA). Cellular senescence in articular joints represents a response of local cells to persistent stress that leads to cell-cycle arrest and enhanced production of inflammatory cytokines, which in turn perpetuates joint damage and leads to significant morbidities in afflicted patients. It has been recently discovered that clearance of senescent cells by novel "senolytic" therapies can attenuate the chronic inflammatory microenvironment of RA and OA, preventing further disease progression and supporting healing processes. To identify patients who might benefit from these new senolytic therapies and monitor therapy response, there is an unmet need to identify and map senescent cells in articular joints and related musculoskeletal tissues. To fill this gap, new imaging biomarkers are being developed to detect and characterize senescent cells in human joints and musculoskeletal tissues. This review article will provide an overview of these efforts. New imaging biomarkers for senescence cells are expected to significantly improve the specificity of state-of-the-art imaging technologies for diagnosing musculoskeletal disorders.

Untargeted Metabolomics Revealed that Quercetin Inhibited Ferroptosis by Improving Metabolic Disorder in the Hippocampus of Perimenopausal Depression Model Rats

Perimenopausal depression is often accompanied by metabolic disorders, which have long-term harmful effects on women's physical and mental health. Quercetin, a kind of phytoestrogen, has anti-inflammatory, antioxidant, and nerve-protective effects, and can regulate various metabolic disorders. This study aims to investigate the effect of quercetin on hippocampal metabolic disorder in perimenopausal depression rat models based on untargeted metabolomics technology. The rat model of perimenopausal depression was established by ovariectomy combined with chronic unpredictable mild stress (OVX-CUMS). Rats with no difference in sucrose preference were randomly divided into four groups (n = 12): sham group, OVX-CUMS group (model group), model plus quercetin group, and model plus 17β-estradiol group. At the end of the experiment, hippocampal tissues were collected for untargeted metabolomics analysis, morphological analysis, and detection of related indicators. Metabolomics identified 23 differential metabolites in the model group, and the pathway analysis discovered hippocampus metabolic abnormalities including the metabolism of arachidonic acid metabolism, glycerophospholipid metabolism, and ubiquinone biosynthesis, accompanied by an increase in oxidative stress, inflammation, and lipid peroxidation indicators. At the same time, the morphological characteristics of ferroptosis occurred in the hippocampus in the model group. These abnormal changes were reversed by treatment with quercetin or 17β-estradiol. Quercetin can improve perimenopausal depression by regulating hippocampal metabolic disorders and reducing hippocampal ferroptosis in rats. These findings provide a new strategy for the use of quercetin in the prevention and treatment of perimenopausal depression.

Quercetin Increases Growth Performance and Decreases Incidence of Diarrhea and Mechanism of Action in Weaned Piglets

This study aimed to investigate the mechanism of quercetin increasing growth performance and decreasing incidence of diarrhea in weaned piglets. Forty-eight Duroc × Landrace × Large White weaned piglets with similar body weight (7.48 ± 0.20 kg, 28 days of age) were randomly divided into four treatments (control, 250 mg/kg quercetin, 500 mg/kg quercetin, and 750 mg/kg quercetin treatments) and fed with basal diet or experimental diet supplemented with quercetin. Performance, diarrhea rate and index, and content of serum anti-inflammatory factors were determined and calculated in weaned piglets; colonic flora and signaling pathways related to anti-inflammation were measured using 16S rDNA sequencing and RNA-seq, respectively. The results showed that compared with control, feed-to-gain ratio and content of serum interferon gamma (IFN-γ) were significantly decreased in the 500 and 750 mg/kg quercetin treatments (P < 0.05); quercetin significantly decreased diarrhea rate and diarrhea index (P < 0.05) and significantly increased the content of serum transforming growth factor (TGF-β) in weaned piglets (P < 0.05); the content of serum NF-κB was significantly decreased in the 750 mg/kg quercetin treatment (P < 0.05); moreover, quercetin significantly increased diversity of colonic flora (P < 0.05), and at the phylum level, the relative abundance of Actinobacteria in the 500 and 750 mg/kg treatments was significantly increased (P < 0.05), and the relative abundance of Proteobacteria in the three quercetin treatments were significantly decreased (P < 0.05) in the colon of weaned piglets; at the genus level, the relative abundance of Clostridium-sensu-stricto-1, Turicibacter, unclassified_f_Lachnospiraceae, Phascolarctobacterium, and Family_XIII _AD3011_group was significantly increased (P < 0.05); the relative abundance of Subdollgranulum and Blautia was significantly decreased in the 500 and 750 mg/kg treatments (P < 0.05); the relative abundance of Eschericha-Shigella, Terrisporobacter, and Eubacterium-coprostanoligenes was significantly increased (P < 0.05); the relative abundance of Streptocococcus, Sarcina, Staphylococcus, and Ruminococcaceae_UCG-008 was significantly decreased in the three quercetin treatments (P < 0.05); the relative abundance of Ruminococcaceae_UCG_014 was significantly increased in the 250 mg/kg quercetin treatment in the colon of weaned piglets (P < 0.05). The results of Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that differentially expressed genes (DEGs) from the quercetin treatments were significantly enriched in nuclear transcription factor-κB (NF-κB) signal pathway (P < 0.05); mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1R1 (IL-1R1), conserved helix-loop-helix ubiquitous kinase (CHUK), toll-like receptor 4 (TLR4), and IL-1β from quercetin treatments were significantly decreased in colonic mucosa of weaned piglets (P < 0.05). In summary, quercetin increased feed conversion ratio and decreased diarrhea through regulating NF-κB signaling pathway, controlling the balance between anti-inflammatory and proinflammatory factors, and modulating intestinal flora, thus promoting the absorption of nutrients in weaned piglets. These results provided the theoretical foundation for applying quercetin in preventing weaning piglets' diarrhea and animal husbandry practices.

Rheumatoid arthritis-recent advances in pathogenesis and the anti-inflammatory effect of plant-derived COX inhibitors

The majority of people with autoimmune disorders, including those with rheumatoid arthritis, osteoarthritis, and tendonitis report pain, stiffness, and inflammation as major contributors to their worse quality of life in terms of overall health. Of all the available treatment options, COX inhibitors are the ones that are utilized most frequently to ease the symptoms. Various signaling cascades have been reported to be involved in the pathogenesis of rheumatoid arthritis which includes JAK/STAT, MAPK, and NF-kB signaling pathways, and several allopathic inhibitors (tofacitinib and baricitinib) have been reported to target the components of these cascades and have received approval for RA treatment. However, the prolonged use of these COX inhibitors and other allopathic drugs can pose serious health challenges due to their significant side effects. Therefore, searching for a more effective and side effect-free treatment for rheumatoid arthritis has unveiled phytochemicals as both productive and promising. Their therapeutic ability helps develop potent and safe drugs targeting immune-inflammatory diseases including RA. Various scientific databases were used for searching articles such as NCBI, SpringerLink, BioMed Central, ResearchGate, Google Scholar, Scopus, Nature, Wiley Online Library, and ScienceDirect. This review lists various phytochemicals and discusses their potential molecular targets in RA treatment, as demonstrated by various in vitro, in vivo (pre-clinical), and clinical studies. Several pre-clinical and clinical studies suggest that various phytochemicals can be an alternative promising intervention for attenuating and managing inflammation-associated pathogenesis of rheumatoid arthritis.

Therapeutic Potential of Plant-Derived Compounds and Plant Extracts in Rheumatoid Arthritis-Comprehensive Review

Rheumatoid arthritis (RA) is a persistent autoimmune disorder that is characterized by joint inflammation, discomfort, and impairment. Despite the existence of several therapeutic approaches, their effectiveness is often restricted and may be linked to unfavorable side effects. Consequently, there has been growing interest in investigating naturally derived compounds as plausible therapeutic agents for RA disease. The objective of this review is to summarize the existing preclinical and clinical evidence regarding the efficacy of naturally extracted compounds and plant extracts in the treatment of RA, focusing on their anti-inflammatory, anti-oxidative, and immunomodulatory properties. Some of the problems with using natural chemicals are the uneven quality of commercially available preparations and the poor bioavailability of these compounds. Future investigations should focus on improving the formulations, conducting thorough clinical trials, and exploring different techniques to fully utilize the intrinsic potential of naturally derived chemicals in treating RA.

Dietary quercetin intake is associated with lower ulcerative colitis risk but not Crohn's disease in a prospective cohort study and in vivo experiments

Objectives: Previous preclinical evidence indicates a protective role of quercetin against inflammatory bowel disease (IBD). However, there is no evidence from human populations, resulting in knowledge gaps regarding the role of quercetin in the IBD development. We aimed to prospectively evaluate the associations between dietary quercetin intake and IBD in humans and in vivo animal models. Methods: We included 187 709 IBD-free participants from the UK Biobank. Dietary information was collected using validated 24-hour dietary recalls and the quercetin intake was estimated based on national nutrient databases. Incident IBD was ascertained via inpatient and primary care data. Cox proportional hazard models were used to estimate the multi-variable adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Experiments were conducted in two chemical-induced (dextran sulfate sodium salt and trinitro-benzene-sulfonic acid) mouse models orally pretreated with quercetin (CAS number: 117-39-5) solution to evaluate the effects of quercetin at physiological levels. Results: After a mean follow-up of 9.7 years, we documented 863 incident IBD. Compared to participants with the lowest quintile intake of quercetin, those in the highest quintiles were associated with a lower risk of IBD (aHR 0.76, 95% CI 0.60-0.95; P-trend = 0.004) and ulcerative colitis (aHR 0.69, 95% CI 0.53-0.91; P-trend = 0.001), but not Crohn's disease (aHR 0.95, 95% CI 0.62-1.45; P-trend = 0.765). Mouse models showed that pretreatment with quercetin could attenuate the chemically induced colitis. Conclusions: Higher quercetin intake was associated with a lower risk of IBD, especially UC. The protective role of quercetin is promising in humans and warrants further investigation into downstream mechanisms.

Effect of SophorOx® on Oxidative Stress and Body Composition in Individuals with High BMI: A Randomized Controlled Trial

Purpose

The study aimed to investigate the efficacy and safety of SophorOx® (LN-OS-22) on oxidative stress and body composition in adults with excessive body weight and obesity.

Participants and Methods

The 56-days randomized, double-blind, placebo-controlled, parallel-group, multi-centric clinical trial had individuals aged 30-60 years with body mass index (BMI) ≥25 to ≤34.9 kg/m2. 68 participants were randomly allocated to LN-OS-22 or placebo groups. The primary outcome was improvement in the oxidative stress. Secondary outcomes were changes in plasma lipopolysaccharide (LPS) and serum malondialdehyde (MDA) levels, weight and waist circumference, inflammatory markers, and quality of life.

Results

At day 56, a statistically significant change in the 8-Isoprostane levels between LN-OS-22 vs placebo was observed (p = 0.0222). As compared to placebo, at the end of study, statistically significant reductions were demonstrated in body weight, waist circumference and BMI in the LN-OS-22 group (p < 0.0001). Also, a statistically significant change when compared to placebo for the energy/stamina domain (p = 0.0300) of the Impact of Weight on Quality of Life-Lite-Clinical Trials Version (IWQOL-Lite-CT) questionnaire was depicted in LN-OS-22 group.

Conclusion

The study demonstrates that LN-OS-22 was effective in reducing the oxidative stress, anthropometrics and improving the quality of life in individuals with overweight and obesity.

Quercetin, a key active ingredient of Jianpi Zishen Xiehuo Formula, suppresses M1 macrophage polarization and platelet phagocytosis by inhibiting STAT3 activation based on network pharmacology

Primary immune thrombocytopenia (ITP) is an autoimmune hemorrhagic disease, and abnormal M1 macrophage polarization participates in the pathogenesis of ITP. Jianpi Zishen Xiehuo (JZX) Formula has a good therapeutic effect on ITP. However, its key active ingredients and molecular mechanisms remain unclear. In this study, we explored the key active ingredients and potential targets of JZX in treating ITP using network pharmacology combined with in vitro experimental verification. A total of 157 active ingredients of JZX were identified from public databases, and quercetin was the most important one. One hundred sixty-five intersection targets of active ingredients in JZX, ITP, and macrophage polarization were obtained by Venn diagram. The top three potential targets were signal transducer and activator of transcription 3 (STAT3), protein kinase B (PKB/AKT) 1, and c-JUN through protein-protein interaction analysis. Molecular docking showed that quercetin had strong binding affinities with them all. In vitro experiment, CD16+ monocytes increased in ITP patients compared with healthy controls, which indicated a M1/M2 polarization imbalance in ITP. The expression levels of M1 polarization markers, CD86, CD80, and inducible nitric oxide synthase (iNOS), M1 polarization-associated cytokines, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6), and antibody-opsonized platelet phagocytosis significantly increased in THP-1 macrophages stimulated with lipopolysaccharide (LPS). Quercetin markedly inhibited the expressions of M1 markers, decreased the levels of TNF-α and IL-6, and down-regulated the phosphorylated STAT3 (p-STAT3) protein, which confirmed the prediction by network pharmacology and molecular docking. Importantly, quercetin significantly reduced the phagocytosis of antibody opsonised platelet. In conclusion, quercetin suppressed platelet phagocytosis in M1 macrophages via its anti-inflammatory effects and may serve as a potential drug for the treatment of ITP. Quercetin could be a key ingredient for JZX against ITP.

Pathophysiology, diagnosis, and herbal medicine-based therapeutic implication of rheumatoid arthritis: an overview

Rheumatoid arthritis (RA) stands as an autoimmune disorder characterized by chronic joint inflammation, resulting in profound physiological alterations within the body. Affecting approximately 0.4-1.3% of the global population, this condition poses significant challenges as current therapeutic approaches primarily offer symptomatic relief, with the prospect of complete recovery remaining elusive. This review delves into the contemporary advancements in understanding the pathophysiology, diagnosis, and the therapeutic potential of herbal medicine in managing RA. Notably, early diagnosis during the initial stages emerges as the pivotal determinant for successful recovery post-treatment. Utilizing tools such as Magnetic Resonance Imaging (MRI), anti-citrullinated peptide antibody markers, and radiography proves crucial in pinpointing the diagnosis of RA with precision. Unveiling the intricate pathophysiological mechanisms of RA has paved the way for innovative therapeutic interventions, incorporating plant extracts and isolated phytoconstituents. In the realm of pharmacological therapy for RA, specific disease-modifying antirheumatic drugs have showcased commendable efficacy. However, this conventional approach is not without its drawbacks, as it is often associated with various side effects. The integration of methodological strategies, encompassing both pharmacological and plant-based herbal therapies, presents a promising avenue for achieving substantive recovery. This integrated approach not only addresses the symptoms but also strives to tackle the underlying causes of RA, fostering a more comprehensive and sustainable path towards healing.

Harnessing the Power of Polyphenols: A New Frontier in Disease Prevention and Therapy

There are a wide variety of phytochemicals collectively known as polyphenols. Their structural diversity results in a broad range of characteristics and biological effects. Polyphenols can be found in a variety of foods and drinks, including fruits, cereals, tea, and coffee. Studies both in vitro and in vivo, as well as clinical trials, have shown that they possess potent antioxidant activities, numerous therapeutic effects, and health advantages. Dietary polyphenols have demonstrated the potential to prevent many health problems, including obesity, atherosclerosis, high blood sugar, diabetes, hypertension, cancer, and neurological diseases. In this paper, the protective effects of polyphenols and the mechanisms behind them are investigated in detail, citing the most recent available literature. This review aims to provide a comprehensive overview of the current knowledge on the role of polyphenols in preventing and managing chronic diseases. The cited publications are derived from in vitro, in vivo, and human-based studies and clinical trials. A more complete understanding of these naturally occurring metabolites will pave the way for the development of novel polyphenol-rich diet and drug development programs. This, in turn, provides further evidence of their health benefits.

Different modalities to manage rheumatoid arthritis: an A to Z story

Aim: To investigate different approaches to RA treatment that might lead to greater efficacy and better safety profiles. Methods: The Search strategy was based on medical subject headings, and screening and selection were based on inclusion/exclusion criteria. Results & discussion: Early therapy is critical for disease control and loss of bodily function. The most promising outcomes came from the development of disease-modifying anti-rheumatic drugs. Different foods have anti-inflammatory and antioxidant qualities that protect against the development of rheumatoid arthritis (RA). Some dietary patterns and supplements have been shown to have potential protective benefits against RA. Conclusion: Improvement in the quality of life of RA patients requires a tailored management approach based on the current patient medical data.

Exploring the therapeutic potential of quercetin: A focus on its sirtuin-mediated benefits

As the global population ages, preventing lifestyle- and aging-related diseases is increasing, necessitating the search for safe and affordable therapeutic interventions. Among nutraceuticals, quercetin, a flavonoid ubiquitously present in various plants, has garnered considerable interest. This review aimed to collate and analyze existing literature on the therapeutic potentials of quercetin, especially its interactions with SIRTs and its clinical applicability based on its bioavailability and safety. This narrative review was based on a literature survey spanning from 2015 to 2023 using PUBMED. The keywords and MeSH terms used were: "quercetin" AND "bioavailability" OR "metabolism" OR "metabolites" as well as "quercetin" AND "SIRTuin" OR "SIRT*" AND "cellular effects" OR "pathway" OR "signaling" OR "neuroprotective" OR "cardioprotective" OR "nephroprotective" OR "antiatherosclerosis" OR "diabetes" OR "antidiabetic" OR "dyslipidemia" AND "mice" OR "rats". Quercetin demonstrates multiple therapeutic activities, including neuroprotective, cardioprotective, and anti-atherosclerotic effects. Its antioxidant, anti-inflammatory, antiviral, and immunomodulatory properties are well-established. At a molecular level, it majorly interacts with SIRTs, particularly SIRT1 and SIRT6, and modulates numerous signaling pathways, contributing to its therapeutic effects. These pathways play roles in reducing oxidative stress, inflammation, autophagy regulation, mitochondrial biogenesis, glucose utilization, fatty acid oxidation, and genome stability. However, clinical trials on quercetin's effectiveness in humans are scarce. Quercetin exhibits a wide range of SIRT-mediated therapeutic effects. Despite the compelling preclinical data, more standardized clinical trials are needed to fully understand its therapeutic potential. Future research should focus on addressing its bioavailability and safety concerns.

Antiplatelet Effects of Flavonoid Aglycones Are Mediated by Activation of Cyclic Nucleotide-Dependent Protein Kinases

Flavonoid aglycones are secondary plant metabolites that exhibit a broad spectrum of pharmacological activities, including anti-inflammatory, antioxidant, anticancer, and antiplatelet effects. However, the precise molecular mechanisms underlying their inhibitory effect on platelet activation remain poorly understood. In this study, we applied flow cytometry to analyze the effects of six flavonoid aglycones (luteolin, myricetin, quercetin, eriodictyol, kaempferol, and apigenin) on platelet activation, phosphatidylserine externalization, formation of reactive oxygen species, and intracellular esterase activity. We found that these compounds significantly inhibit thrombin-induced platelet activation and decrease formation of reactive oxygen species in activated platelets. The tested aglycones did not affect platelet viability, apoptosis induction, or procoagulant platelet formation. Notably, luteolin, myricetin, quercetin, and apigenin increased thrombin-induced thromboxane synthase activity, which was analyzed by a spectrofluorimetric method. Our results obtained from Western blot analysis and liquid chromatography-tandem mass spectrometry demonstrated that the antiplatelet properties of the studied phytochemicals are mediated by activation of cyclic nucleotide-dependent signaling pathways. Specifically, we established by using Förster resonance energy transfer that the molecular mechanisms are, at least partly, associated with the inhibition of phosphodiesterases 2 and/or 5. These findings underscore the therapeutic potential of flavonoid aglycones for clinical application as antiplatelet agents.

Osteoarthritis: Insights into Diagnosis, Pathophysiology, Therapeutic Avenues, and the Potential of Natural Extracts

Osteoarthritis (OA) stands as a prevalent and progressively debilitating clinical condition globally, impacting joint structures and leading to their gradual deterioration through inflammatory mechanisms. While both non-modifiable and modifiable factors contribute to its onset, numerous aspects of OA pathophysiology remain elusive despite considerable research strides. Presently, diagnosis heavily relies on clinician expertise and meticulous differential diagnosis to exclude other joint-affecting conditions. Therapeutic approaches for OA predominantly focus on patient education for self-management alongside tailored exercise regimens, often complemented by various pharmacological interventions primarily targeting pain alleviation. However, pharmacological treatments typically exhibit short-term efficacy and local and/or systemic side effects, with prosthetic surgery being the ultimate resolution in severe cases. Thus, exploring the potential integration or substitution of conventional drug therapies with natural compounds and extracts emerges as a promising frontier in enhancing OA management. These alternatives offer improved safety profiles and possess the potential to target specific dysregulated pathways implicated in OA pathogenesis, thereby presenting a holistic approach to address the condition's complexities.

Higher Dietary Quercetin Intake Is Associated with Lower Risk of Adverse Outcomes among Individuals with Inflammatory Bowel Disease in a Prospective Cohort Study

BACKGROUND

Cumulative preclinical evidence reported quercetin, a major flavonoid, can attenuate the disease activity of inflammatory bowel diseases (IBD). However, there is limited evidence that supports the benefits of quercetin for patients with IBD.

OBJECTIVES

To investigate whether dietary quercetin intake is associated with adverse outcomes among individuals with IBD in a prospective cohort study.

METHODS

We included 2293 participants with IBD (764 Crohn's disease [CD] and 1529 ulcerative colitis [UC]) from the UK Biobank. Dietary information was collected using validated 24-h dietary assessments, and quercetin intake was estimated based on national nutrient databases. Two outcomes, enterotomy and all-cause mortality, were obtained based on the national data. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

After a mean (standard deviation) follow-up of 9.6 (1.8) y, we documented 193 enterotomy events and 176 deaths. Compared with participants with the lowest quartile intake of quercetin, those in the highest quartiles were associated with lower risk of enterotomy (HR: 0.46; 95% CI: 0.28, 0.76) and all-cause mortality (HR: 0.53; 95% CI: 0.33, 0.83) in IBD. The inverse associations between quercetin and enterotomy were consistent in CD (HR: 0.30; 95% CI: 0.12, 0.78) but not UC (HR: 0.58; 95% CI: 0.32, 1.07), while the inverse associations between quercetin and mortality were consistent both in CD (HR: 0.37; 95% CI: 0.15, 0.92) and UC (HR: 0.55; 95% CI: 0.31, 0.95).

CONCLUSIONS

Higher dietary intake of quercetin was associated with lower risk of enterotomy and all-cause mortality in IBD. Our study provides novel evidence that further suggests the benefits of quercetin for patients with IBD, while also calling for further validation in other cohorts and clinical trials.

The Impact of Three-Month Quercetin Intake on Quality of Life and Anxiety in Patients With Type II Diabetes Mellitus: An Early Data Analysis From a Randomized Controlled Trial

BACKGROUND

Diabetes is a high-prevalence, major chronic metabolic disease demanding effective interventions. Quercetin, a phytochemical with potential health benefits, has garnered interest for its therapeutic properties.

AIM

This study was designed to capture the early efficacy and clinical safety aspects following quercetin administration in patients with type II diabetes mellitus (T2DM).

METHODS

The main study involved a randomized allocation procedure to assign non-insulin-treated patients attending the 4th Health Unit of Heraklion to intervention and control groups based on age and sex. The intervention group (n=50) received 500 mg of quercetin daily for 12 + (8 free intervals) + 12 weeks, alongside their usual treatment, while the control group (n=50) did not. After randomization, for the intermediary 12-week follow-up, data from 38 patients (intervention: 20; control: 18) were analyzed in this report. All subjects provided informed consent for the collection of anthropometric measurements, vital signs, daily habits data, and PiKo-6 spirometric readings. Additionally, participants responded to the Short Anxiety Screening Test (SAST) and the 36-Item Short Form Health Survey (SF-36) questionnaires.

RESULTS

Thirty-eight participants were included (60% men and 40% women in the intervention group; 38.9% men and 61.1% women in the control group). In the treatment arm, Forced Expiratory Volume in the first second (FEV1) measured with PiKo-6 showed a Δ%- change for the intervention arm: +6.8%, control: -0.2% (p=0.059), systolic blood pressure; intervention: -7.4%, control: -3.7% (p=0.117), waist circumference; intervention: -1.5% control: -0.7% (p=0.455) and night-time sleep; intervention: +5.3%, control: +1.4% (p=0.926) were favourably influenced. The treatment group exhibited significant enhancements in both anxiety levels assessed by the anxiety symptoms scale (SAST-10, p=0.026) and quality of life evaluated by the SF-36 (p<0.001).

CONCLUSIONS

Positive evidence is emerging for a pleiotropic effect of quercetin intake in patients with T2DM, specifically in terms of anxiety reduction and amelioration of life quality, in just 12 weeks of administration and without adverse effects, indicating clinical safety and underscoring its potential for integration in T2DM supportive care.

Isorhamnetin Alleviates Mitochondrial Injury in Severe Acute Pancreatitis via Modulation of KDM5B/HtrA2 Signaling Pathway

Severe acute pancreatitis (SAP), a widespread inflammatory condition impacting the abdomen with a high mortality rate, poses challenges due to its unclear pathogenesis and the absence of effective treatment options. Isorhamnetin (ISO), a naturally occurring flavonoid, demonstrates robust antioxidant and anti-inflammatory properties intricately linked to the modulation of mitochondrial function. However, the specific protective impact of ISO on SAP remains to be fully elucidated. In this study, we demonstrated that ISO treatment significantly alleviated pancreatic damage and reduced serum lipase and amylase levels in the mouse model of SAP induced by sodium taurocholate (STC) or L-arginine. Utilizing an in vitro SAP cell model, we found that ISO co-administration markedly prevented STC-induced pancreatic acinar cell necrosis, primarily by inhibiting mitochondrial ROS generation, preserving ATP production, maintaining mitochondrial membrane potential, and preventing the oxidative damage and release of mitochondrial DNA. Mechanistically, our investigation identified that high-temperature requirement A2 (HtrA2) may play a central regulatory role in mediating the protective effect of ISO on mitochondrial dysfunction in STC-injured acinar cells. Furthermore, through an integrated approach involving bioinformatics analysis, molecular docking analysis, and experimental validation, we uncovered that ISO may directly impede the histone demethylation activity of KDM5B, leading to the restoration of pancreatic HtrA2 expression and thereby preserving mitochondrial function in pancreatic acinar cells following STC treatment. In conclusion, this study not only sheds new light on the intricate molecular complexities associated with mitochondrial dysfunction during the progression of SAP but also underscores the promising value of ISO as a natural therapeutic option for SAP.

Naodesheng decoction regulating vascular function via G-protein-coupled receptors: network analysis and experimental investigations

Introduction: Ischemic stroke (IS) is a detrimental neurological disease with limited treatment options. Recanalization of blocked blood vessels and restoring blood supply to ischemic brain tissue are crucial for post-stroke rehabilitation. The decoction Naodesheng (NDS) composed of five Chinese botanical drugs, including Panax notoginseng (Burk.) F. H. Chen, Ligusticum chuanxiong Hort., Carthamus tinctorius L., Pueraria lobata (Willd.) Ohwi, and Crataegus pinnatifida Bge., is a blood-activating and stasis-removing herbal medicine commonly used for the clinical treatment of cerebrovascular diseases in China. However, the material basis of NDS on the effects of blood circulation improvement and vascular tone regulation remains unclear. Methods: A database comprising 777 chemical metabolites of NDS was constructed. Then, the interactions between various herbal metabolites of NDS and five vascular tone modulation G-protein-coupled receptors (GPCRs), including 5-HT1AR, 5-HT1BR, β2-AR, AT1R, and ETBR, were assessed by molecular docking. Using network analysis and vasomotor experiment of the cerebral basilar artery, the potential material basis underlying the vascular regulatory effects of NDS was further explored. Results: The Naodesheng Effective Component Group (NECG) was found to induce relaxation of rat basilar artery rings precontracted using Endothelin-1 (ET-1) and KCl in vitro in a dose-dependent manner. Several metabolites of NDS, including C. tinctorius, C. pinnatifida, and P. notoginseng, were found to be the main plant resources of metabolites with high docking scores. Furthermore, several metabolites in NDS, including formononetin-7-glucoside, hydroxybenzoyl-coumaric anhydride, methoxymecambridine, puerarol, and pyrethrin II, were found to target multiple vascular GPCRs. Metabolites with moderate-to-high binding energy were verified to have good rat basilar artery-relaxing effects, and the maximum artery relaxation effects of all three metabolites, namely, isorhamnetin, kaempferol, and daidzein, were found to exceed 90%. Moreover, metabolites of NDS were found to exert a synergistic effect by interacting with vascular GPCR targets, and these metabolites may contribute to the cerebrovascular regulatory function of NDS. Discussion: The study reports that various metabolites of NDS contribute to its vascular tone regulating effects and demonstrates the multi-component and multi-target characteristics of NDS. Among them, metabolites with moderate-to-high binding scores in NDS may play an important role in regulating vascular function.

Amplification of the antioxidant properties of myricetin, fisetin, and morin following their oxidation

Quercetin oxidation leads to the formation of a metabolite, 2-(3,4-dihydroxybenzoyl)-2,4,6-trihydroxy-3(2H)-benzofuranone, whose antioxidant potency was recently reported to be a 1000-fold higher than that of its precursor. The formation of similar metabolites (BZF) is limited to certain flavonols (FL), among which are myricetin, fisetin, and morin. Here we addressed the consequences of inducing the auto-oxidation of these flavonols in terms of their antioxidant properties (assessed in ROS-exposed Caco-2 cells). The mixtures that result from their oxidation (FLox) exhibited antioxidant activities 10-to-50-fold higher than those of their precursors. Such amplification was fully attributable to the presence of BZF in each FLox (established by HPLC-ESI-MS/MS and chemical subtraction techniques). An identical amplification was also found when the antioxidant activities of BZF, isolated from each FLox, and FL were compared. These findings warrant the search of these BZF in edible plants and their subsequent evaluation as a new type of functional food ingredients.

Polyphenols as Potential Geroprotectors

Significance: Currently, a large amount of evidence of beneficial effects of diets enriched with polyphenols on various aspects of health has been accumulated. These phytochemicals have a geroprotective potential slowing down the pathological processes associated with aging and ensuring longevity. In this study, a comprehensive analysis was conducted to determine the adherence of individual polyphenols to geroprotector criteria. Data from experimental models, clinical trials, and epidemiological studies were analyzed. Recent Advances: Sixty-two polyphenols have been described to increase the life span and improve biomarkers of aging in animal models. They act via evolutionarily conserved molecular mechanisms, including hormesis and maintenance of redox homeostasis, epigenetic regulation, response to cellular damage, metabolic control, and anti-inflammatory and senolytic activity. Epidemiological and clinical studies suggest that certain polyphenols have a potential for prevention and treatment of various diseases, including cancer, metabolic disorders, and cardiovascular conditions in humans. Critical Issues: Among the reviewed phytochemicals, chlorogenic acid, quercetin, epicatechin, genistein, resveratrol, and curcumin were identified as compounds with the highest geroprotective potential. However, there is a lack of unambiguous information on the effectiveness and safety of polyphenols for increasing health span, preventing and treating aging-associated diseases in humans. Future Directions: Further research is needed to fully understand the effects of polyphenols considering their long-term consumption, metabolic modification and bioavailability, complex interactions between different groups of polyphenols and with other phytochemicals, as well as their effects on individuals with different health status. Antioxid. Redox Signal. 40, 564-593.

Rheumatoid arthritis molecular targets and their importance to flavonoid-based therapy

Rheumatoid arthritis (RA) is a progressive, chronic, autoimmune, inflammatory, and systemic condition that primarily affects the synovial joints and adjacent tissues, including bone, muscle, and tendons. The World Health Organization recognizes RA as one of the most prevalent chronic inflammatory diseases. In the last decade, there was an expansion on the available RA therapeutic options which aimed to improve patient's quality of life. Despite the extensive research and the emergence of new therapeutic approaches and drugs, there are still significant unwanted side effects associated to these drugs and still a vast number of patients that do not respond positively to the existing therapeutic strategies. Over the years, several references to the use of flavonoids in the quest for new treatments for RA have emerged. This review aimed to summarize the existing literature about the flavonoids' effects on the major pathogenic/molecular targets of RA and their potential use as lead compounds for the development of new effective molecules for RA treatment. It is demonstrated that flavonoids can modulate various players in synovial inflammation, regulate immune cell function, decrease synoviocytes proliferation and balance the apoptotic process, decrease angiogenesis, and stop/prevent bone and cartilage degradation, which are all dominant features of RA. Although further investigation is necessary to determine the effectiveness of flavonoids in humans, the available data from in vitro and in vivo models suggest their potential as new disease-modifying anti-rheumatic drugs. This review highlights the use of flavonoids as a promising avenue for future research in the treatment of RA.

Effect of onion (Allium cepa L.) peel extract on natural killer cell and cytokines in a randomized, double-blind, placebo-controlled trial

BACKGROUND/OBJECTIVES

Onion, particularly onion peel, is a quercetin-rich food with, anti-inflammatory and immunomodulatory effects. However, the effect of onion peel extract (OPE) in humans is unclear. Thus, the present study aimed to investigate whether OPE improves natural killer (NK) cell activity and cytokine concentration in a randomized double-blind placebo-controlled trial.

SUBJECTS/METHODS

Eighty participants aged 19-64 yrs old with a white blood cell count of 4,000-10,000 cells/µL, symptoms of upper respiratory infection at least once within the previous 12 mon, and perceived stress scale (PSS) over 14 were included. Participants were randomly assigned to take either 1,000 mg/day OPE or a placebo for 8 weeks.

RESULTS

Compliance were 87.4 ± 8.6% and 86.9 ± 79.0% in OPE and placebo groups. Compared to the placebo, OPE supplementation improved "Hoarseness" (P = 0.038) of the Wisconsin Upper Respiratory Symptom Survey (WURSS)-21 symptom, and stress scores (P = 0.001; 0.021) of PSS. Supplementation of OPE had no significant effect on NK cell activity and concentrations of cytokines such as interleukin (IL)-2, IL-6, IL-12, IL-1β, interferon-γ, and tumor necrosis factor-α. At baseline, the WURSS-21 symptom and PSS score (P = 0.024; 0.026) were higher in the OPE group than the placebo group. Among participants with higher than median WURSS-21 symptom score, OPE supplementation increased NK cell activity (P = 0.038). Supplementation of OPE had no significant effects on safety measurements and adverse events.

CONCLUSIONS

The present study suggested that OPE supplementation improves NK cell activity in participants with moderate upper respiratory symptoms without any significant adverse effects.

Trial Registration

ClinicalTrials.gov Identifier: NCT05666752.

Research advances of Zanthoxylum bungeanum Maxim. polyphenols in inflammatory diseases

Zanthoxylum bungeanum Maxim., commonly known as Chinese prickly ash, is a well-known spice and traditional Chinese medicine ingredient with a rich history of use in treating inflammatory conditions. This review provides a comprehensive overview of the botanical classification, traditional applications, and anti-inflammatory effects of Z. bungeanum, with a specific focus on its polyphenolic components. These polyphenols have exhibited considerable promise, as evidenced by preclinical studies in animal models, suggesting their therapeutic potential in human inflammatory diseases such as ulcerative colitis, arthritis, asthma, chronic obstructive pulmonary disease, cardiovascular disease, and neurodegenerative conditions. This positions them as a promising class of natural compounds with the potential to enhance human well-being. However, further research is necessary to fully elucidate their mechanisms of action and develop safe and effective therapeutic applications.

Research progress in arthritis treatment with the active components of Herba siegesbeckiae

Arthritis is a group of diseases characterized by joint pain, swelling, stiffness, and limited movement. Osteoarthritis, rheumatoid arthritis, and gouty arthritis are the most common types of arthritis. Arthritis severely affects the quality of life of patients and imposes a heavy financial and medical burden on their families and society at large. As a widely used traditional Chinese medicine, Herba siegesbeckiae has many pharmacological effects such as anti-inflammatory and analgesic, anti-ischemic injury, cardiovascular protection, and hypoglycemic. In addition, it has significant therapeutic effects on arthritis. The rich chemical compositions of H. siegesbeckiae primarily include diterpenoids, sesquiterpenoids, and flavonoids. As one of the main active components of H. siegesbeckiae, kirenol and quercetin play a vital role in reducing arthritis symptoms. In the present study, the research progress in arthritis treatment with the active components of H. siegesbeckiae is reviewed.

Cynanchum komarovii extract for the treatment of rheumatoid arthritis by acting on synovial cells in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum komarovii (CK), the northwest Chinese region's common medicinal herb, was traditionally utilized to treat arthritis, toothache, bald sores and cholecystitis. Various forms of arthritis can be treated with CK, based on "Medicinal Plants of Chinese Desert Areas". However, the exact mechanism of action in rheumatoid arthritis (RA) is uncertain.

AIM OF THE STUDY

To evaluate the in vitro and in vivo effects of CK extracts on RA and to preliminarily investigate its anti-RA mechanism of action.

MATERIALS AND METHODS

The main components of CK extract were analyzed by HPLC method. The effects of CK on the proliferation and apoptosis of human rheumatoid arthritis fibroblast-like synoviocytes (HFLS-RA) cells and the expression of apoptosis-related proteins in HFLS-RA cells were evaluated by CCK8 assay, flow cytometry and WB assay. To verify the anti-RA effect of CK extracts in vivo, a collagen-induced arthritis (CIA) rat model was established. The rats were divided into six groups: normal group, model group, CK high-dose group (1000 mg/kg, CK-H), CK medium-dose group (500 mg/kg, CK-M), CK low-dose group (250 mg/kg, CK-L) and methotrexate-positive drug group (MTX); the drug was administered continuously for 28 days. Body weight changes, joint swelling, arthritis index, bone density, ankle lesions, immune organ index, splenic lesions and inflammatory factor expression were used to evaluate the in vivo anti-RA activity of the extract.

RESULTS

The findings of in vitro experiments showed that 10% CK-containing serum decreased the expression level of Bcl-2, increased the expression levels of Bax and Cleaved Caspase-3 in synovial cells, and prevented TNF-α induced aberrant proliferation and apoptotic antagonism in HFLS-RA cells. According to in vivo studies, CK extract at doses above 250 mg/kg was effective in controlling the levels of inflammatory factors, lowering the arthritis index, and improving foot swelling in CIA rats. When administered at doses up to 1000 mg/kg, CK extract significantly improved synovial lesions, increased bone density, and decreased abnormally elevated immune organ index in CIA rats.

CONCLUSIONS

CK has significant anti-RA activity, and its anti-RA mechanism of action may be related to the regulation of the expression levels of apoptosis related proteins and the promotion of apoptosis in synovial cells.

Quercetin is a Potential Therapy for Rheumatoid Arthritis via Targeting Caspase-8 Through Ferroptosis and Pyroptosis

Background

Rheumatoid arthritis (RA) is one of the most common chronic inflammatory autoimmune diseases. However, the underlying molecular mechanisms of its pathogenesis are unknown. This study aimed to identify the common biomarkers of ferroptosis and pyroptosis in RA and screen potential drugs.

Methods

The RA-related differentially expressed genes (DEGs) in GSE55235 were screened by R software and intersected with ferroptosis and pyroptosis gene libraries to obtain differentially expressed ferroptosis-related genes (DEFRGs) and differentially expressed pyroptosis-related genes (DEPRGs). We performed Gene Ontology (GO), Kyoto Encyclopedia of the Genome (KEGG), ClueGO, and Protein-Protein Interaction (PPI) analysis for DEFRGs and DEPRGs and validated them by machine learning. The microRNA/transcription factor (TF)-hub genes regulatory network was further constructed. The key gene was validated using the GSE77298 validation set, cellular validation was performed in in vitro experiments, and immune infiltration analysis was performed using CIBERSORT. Network pharmacology was used to find key gene-targeting drugs, followed by molecular docking and molecular dynamics simulations to analyze the binding stability between small-molecule drugs and large-molecule proteins.

Results

Three hub genes (CASP8, PTGS2, and JUN) were screened via bioinformatics, and the key gene (CASP8) was validated and obtained through the validation set, and the diagnostic efficacy was verified to be excellent through the receiver operating characteristic (ROC) curves. The ferroptosis and pyroptosis phenotypes were constructed by fibroblast-like synoviocytes (FLS), and caspase-8 was detected and validated as a common biomarker for ferroptosis and pyroptosis in RA, and quercetin can reduce caspase-8 levels. Quercetin was found to be a potential target drug for caspase-8 by network pharmacology, and the stability of their binding was further verified using molecular docking and molecular dynamics simulations.

Conclusion

Caspase-8 is an important biomarker for ferroptosis and pyroptosis in RA, and quercetin is a potential therapy for RA via targeting caspase-8 through ferroptosis and pyroptosis.

Quercetin as a Therapeutic Product: Evaluation of Its Pharmacological Action and Clinical Applications-A Review

Quercetin is the major polyphenolic flavonoid that belongs to the class called flavanols. It is found in many foods, such as green tea, cranberry, apple, onions, asparagus, radish leaves, buckwheat, blueberry, broccoli, and coriander. It occurs in many different forms, but the most abundant quercetin derivatives are glycosides and ethers, namely, Quercetin 3-O-glycoside, Quercetin 3-sulfate, Quercetin 3-glucuronide, and Quercetin 3'-metylether. Quercetin has antioxidant, anti-inflammatory, cardioprotective, antiviral, and antibacterial effects. It is found to be beneficial against cardiovascular diseases, cancer, diabetes, neuro-degenerative diseases, allergy asthma, peptic ulcers, osteoporosis, arthritis, and eye disorders. In pre-clinical and clinical investigations, its impacts on various signaling pathways and molecular targets have demonstrated favorable benefits for the activities mentioned above, and some global clinical trials have been conducted to validate its therapeutic profile. It is also utilized as a nutraceutical due to its pharmacological properties. Although quercetin has several pharmacological benefits, its clinical use is restricted due to its poor water solubility, substantial first-pass metabolism, and consequent low bioavailability. To circumvent this limited bioavailability, a quercetin-based nanoformulation has been considered in recent times as it manifests increased quercetin uptake by the epithelial system and enhances the delivery of quercetin to the target site. This review mainly focuses on pharmacological action, clinical trials, patents, marketed products, and approaches to improving the bioavailability of quercetin with the use of a nanoformulation.

Mechanistic prospective and pharmacological attributes of quercetin in attenuation of different types of arthritis

Arthritis is a frequent autoimmune disease with undefined etiology and pathogenesis. Scientific community constantly fascinating quercetin (QUR), as it is the best-known flavonoid among others for curative and preventive properties against a wide range of diseases. Due to its multifaceted activities, the implementation of QUR against various types of arthritis namely, rheumatoid arthritis (RA), osteoarthritis (OA), gouty arthritis (GA) and psoriotic arthritis (PsA) has greatly increased in recent years. Many research evidenced that QUR regulates a wide range of pathways for instance NF-κB, MAK, Wnt/β-catenine, Notch, etc., that are majorly associated with the inflammatory mechanisms. Besides, the bioavailability of QUR is a major constrain to its therapeutic potential, and drug delivery techniques have experienced significant development to overcome the problem of its limited application. Hence, this review compiled the cutting-edge experiments on versatile effects of QUR on inflammatory diseases like RA, OA, GA and PsA, sources and bioavailability, therapeutic challenges, pharmacokinetics, clinical studies as well as toxicological impacts. The use of QUR in a health context would offer a tearing and potential therapeutic method, supporting the advancement of public health, particularly, of arthritic patients worldwide.

Oxidative Stress Mediated Therapy in Patients with Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

The aim of this meta-analysis is to explore all the available literature to obtain updated data about the potential use of antioxidants in the treatment of rheumatoid arthritis (RA) and its ability to reduce disease progression and cardiovascular risk.

METHODS

This systematic review and meta-analysis was performed strictly in accordance with the PRISMA guidelines. English and Chinese databases were searched with a retrieval time up to March 2023. These databases included the PubMed, Embase, Medline Complete, Web of Sciences and Cochrane Collaboration, Wanfang, China National Knowledge Infrastructure, and VIP databases. This literature search was formulated by the two researchers independently. The search strategy consists of reading, collecting the literature, and conducting the preliminary screening. After that, they provide the final selection of the literature according to the inclusion criteria and data extraction. Also, for all studies, the risk bias was assessed to evaluate the quality of the included references. The content of the risk assessment of bias included the following criteria: random allocation method, allocation plan hiding, blind method, completeness of result data, and selectivity of reporting of results, as well as other biases. The main outcomes were clinical efficiency of antioxidant therapy (C-reactive protein, DAS28 score, HAQ, Number of tender joints, etc.) and oxidative stress indicators (catalase, superoxide dismutase, or total antioxidant capacity).

RESULTS

We observed, in most of the studies, the small or moderate effects of antioxidant treatment. The mean effect size is 0.525, and that means that moderate effects were observed in 30 selected RCTs. Also, this effect is confirmed in the 1652 patients with RA with the mean confidence interval of 0.276 (lower limit) and 0.983 (upper limit). Cohen coefficient was calculated at 0.05.

CONCLUSION

The existing evidence is that antioxidants can reduce systemic and local oxidative stress and can reduce damage as the main agent involved in autoimmune diseases such as rheumatoid arthritis.

Proposed mechanisms of action of herbal drugs and their biologically active constituents in the treatment of coughs: an overview

Various medicinal plants find their use in cough treatment, based on traditions and long-term experience. Pharmacological principles of their action, however, are much less known. Herbal drugs usually contain a mixture of potentially active compounds, which can manifest diverse effects. Expectorant or antitussive effects, which can be accompanied by others, such as anti-inflammatory or antibacterial, are probably the most important in the treatment of coughs. The aim of this review is to summarize the current state of knowledge of the effects of medicinal plants or their constituents on cough, based on reliable pharmacological studies. First, a comprehensive description of each effect is provided in order to explain the possible mechanism of action in detail. Next, the results related to individual plants and substances are summarized and critically discussed based on pharmacological in vivo and in vitro investigation.

The effects of tea polyphenols on emotional homeostasis: Understanding dementia risk through stress, mood, attention & sleep

Decades of research provide evidence that certain phytochemicals in tea (Camellia sinensis) and other herbal beverages are protective against the development of sporadic types of dementia in later life. Since tea drinking is an economical and widely adopted social-cultural practice across all age groups, it is an ideal product to target in designing low-cost dietary interventions for Alzheimer's Disease (AD), the most prevalent form of dementia. In this review, we focus on the protective roles of tea-derived polyphenols and other phytochemicals on mood, the stress response, attention, and sleep, in keeping with the perspective that many early neuropathological events in AD may stem, in part, from allostatic overload. This approach aligns with the perspective that many forms of dementia, including AD, begin to take root in the brain decades prior to symptom onset, underscoring the need for early uptake of accessible and viable lifestyle interventions. The findings reviewed here suggest that consuming green and oolong tea can improve mood and reduce overall stress. However, given the caffeine content in tea and its association with stress reactivity, the effects of daily whole tea consumption on the emotional state are likely dose-dependent with an inverted-U relationship to wellbeing. Plant-based beverages that are to be consumed in high daily quantities for health purposes and which are naturally free of caffeine, such as Rooibos, may be more appropriate as a dietary supplement for managing emotional regulation over the lifetime.

Drug repurposing based on the similarity gene expression signatures to explore for potential indications of quercetin: a case study of multiple sclerosis

Quercetin (QR) is a natural flavonol compound widely distributed in the plant kingdom with extensive pharmacological effects. To find the potential clinical indications of QR, 156 differentially expressed genes (DEGs) regulated by QR were obtained from the Gene Expression Omnibus database, and new potential pharmacological effects and clinical indications of QR were repurposed by integrating compounds with similar gene perturbation signatures and associated-disease signatures to QR based on the Connectivity Map and Coexpedia platforms. The results suggested QR has mainly potential therapeutic effects on multiple sclerosis (MS), osteoarthritis, type 2 diabetes mellitus, and acute leukemia. Then, MS was selected for subsequent animal experiments as a representative potential indication, and it found that QR significantly delays the onset time of classical MS model animal mice and ameliorates the inflammatory infiltration and demyelination in the central nervous system. Combined with network pharmacology technology, the therapeutic mechanism of QR on MS was further demonstrated to be related to the inhibition of the expression of inflammatory cytokines (TNF-α, IL-6, IL-1β, IFN-γ, IL-17A, and IL-2) related to TNF-α/TNFR1 signaling pathway. In conclusion, this study expanded the clinical indications of QR and preliminarily confirmed the therapeutic effect and potential mechanism of QR on MS.

A randomized, placebo-controlled trial evaluating the safety of excessive administration of kaempferol aglycone

Kaempferol (KMP) is an important flavonoid in many fruits and vegetables. Preclinical studies on KMP have reported its pharmacological effects, including antimicrobial, antioxidant, anti-inflammatory, antitumor, antidiabetic, myocardial protective, and neuroprotective effects. Additionally, some epidemiological studies have revealed a negative association between the consumption of KMP-containing foods and the risk of developing several disorders, such as cancer and cardiovascular diseases. Thus, although a large body of literature has demonstrated the benefits of KMP supplementation, there are no reports of clinical trials evaluating the safety of KMP aglycone administration or KMP aglycone-rich food consumption. The purpose of this study was to evaluate the safety of a high dose of KMP aglycone by administrating KMP aglycone-containing supplements to healthy adults. This study had a randomized, double-blind, placebo-controlled design and a 4-week duration. Participants were randomly allocated to the KMP (n = 24) or placebo (n = 24) group. For 4 weeks, the KMP group received a capsule containing 50-mg KMP daily, a dose approximately five times higher than the estimated human dietary intake. The placebo group received a capsule containing cornstarch-based powder daily. The general toxicity parameters were evaluated by examining the characteristics of the participants, hematological and blood biochemical parameters, general urinalysis, qualitative urine tests, and adverse events. No clinical changes were observed in anthropometric and blood pressure measurements or blood and urine parameters in the KMP group compared to those in the placebo group. Furthermore, no adverse events owing to KMP aglycone administration occurred. The study results revealed that the consumption of 50-mg KMP aglycone daily for 4 weeks is safe in healthy adults.

The effect of resveratrol, curcumin and quercetin combination on immuno-suppression of tumor microenvironment for breast tumor-bearing mice

Resveratrol, curcumin, and quercetin are the secondary metabolites from medicinal food homology plants, that have been proven their potency in cancer treatment. However, the antitumor effect of a single component is weak. So, herein, we designed an antitumor compound named RCQ composed of resveratrol, curcumin, and quercetin. This study examined the effect on tumorigenesis and development of 4T1 breast cancer-bearing mice following administering RCQ by intragastric administration. RCQ increased the recruitment of T cells and reduced the accumulation of neutrophils and macrophages in the tumor microenvironment. Meanwhile, RCQ suppressed the development of tumor-infiltrating lymphocytes into immunosuppressive cell subpopulations, including CD4+ T cells to T helper Type 2 type (Th2), tumor-associated neutrophils (TANs) to the N2 TANs, and tumor-associated macrophages (TAMs) cells to M2 TAMs. RCQ reversed the predominance of immunosuppressive infiltrating cells in the tumor microenvironment and tipped the immune balance toward an immune activation state. In vitro the study showed that RCQ significantly increased reactive oxygen species (ROS), reduce mitochondrial membrane potentials in cancer cells, and modulate pro-apoptotic Bcl-2 family members. In conclusion, RCQ can promote the ROS apoptosis mechanism of tumor cells and alleviate immunosuppression of the tumor microenvironment to enhance the anti-tumor effect.

Effects of Natural Product-Derived Compounds on Inflammatory Pain via Regulation of Microglial Activation

Inflammatory pain is a type of pain caused by tissue damage associated with inflammation and is characterized by hypersensitivity to pain and neuroinflammation in the spinal cord. Neuroinflammation is significantly increased by various neurotransmitters and cytokines that are expressed in activated primary afferent neurons, and it plays a pivotal role in the development of inflammatory pain. The activation of microglia and elevated levels of pro-inflammatory cytokines are the hallmark features of neuroinflammation. During the development of neuroinflammation, various intracellular signaling pathways are activated or inhibited in microglia, leading to the regulation of inflammatory proteins and cytokines. Numerous attempts have been conducted to alleviate inflammatory pain by inhibiting microglial activation. Natural products and their compounds have gained attention as potential candidates for suppressing inflammatory pain due to verified safety through centuries of use. Many studies have also shown that natural product-derived compounds have the potential to suppress microglial activation and alleviate inflammatory pain. Herein, we review the literature on inflammatory mediators and intracellular signaling involved in microglial activation in inflammatory pain, as well as natural product-derived compounds that have been found to suppress microglial activation. This review suggests that natural product-derived compounds have the potential to alleviate inflammatory pain through the suppression of microglial activation.

Pharmacological Activity of Flavonoid Quercetin and Its Therapeutic Potential in Testicular Injury

Quercetin is a natural flavonoid widely found in natural fruits and vegetables. Recent studies have shown that quercetin mediates multiple beneficial effects in a variety of organ damage and diseases, and is considered a healthcare supplement with health-promoting potential. Male infertility is a major health concern, and testicular damage from multiple causes is an important etiology. Previous studies have shown that quercetin has a protective effect on reproductive function. This may be related to the antioxidant, anti-inflammatory, and anti-apoptotic biological activities of quercetin. Therefore, this paper reviews the mechanisms by which quercetin exerts its pharmacological activity and its role in testicular damage induced by various etiologies. In addition, this paper compiles the application of quercetin in clinical trials, demonstrating its practical effects in regulating blood pressure and inhibiting cellular senescence in human patients. However, more in-depth experimental studies and clinical trials are needed to confirm the true value of quercetin for the prevention and protection against testicular injury.

Environmental toxicants and health adversities: A review on interventions of phytochemicals

Toxicity arising from environmental contaminants has attracted global interest in the last few decades, due to the high morbidity and mortality associated with them. Efforts have been made to combat the consequential outcomes of environmental toxicity in humans through traditional remediation techniques and therapeutic measures which have been hampered by one or more limitations. Consequently, this scenario has triggered interest in the medicinal properties of phytochemicals. Thus, this review gives a succinct and in-depth elucidation of the various environmental contaminants and their toxicity effects on humans. It delves into the various classes of phytochemicals and their intervention roles. The study adopted a desk review of existing literatures from scientific reports and peer reviewed articles through triangulation of data sources. "Phytochemicals" are group of secondary metabolites obtained from plants with medicinal properties. These groups of compounds are included but not limited to flavonoids, tannins, saponins, alkaloids, cardenoloids, terpenoids, and phytosteroids. This review corroborates the prophylactic and therapeutics efficacy of these phytochemicals as anti-metastatic, anti-inflammatory, anti-aging, anti-oxidant, anti-microbial and live saving substances with empirical findings from several laboratory, clinical trials and epidemiologic studies. It conclude that given the wide range of medicinal properties of phytochemicals, there is an urgent need for its full optimization in the pharmaceutical industry and future studies should focus on identifying the bioactive molecules in these compounds and its effectiveness against mixer toxicity.

Non-pharmacological interventions in the treatment of rheumatoid arthritis: A systematic review and meta-analysis

PURPOSE

To investigate the role of non-pharmaceutical therapies on disease activity in rheumatoid arthritis through systematic review and meta-analysis.

METHODS

A review of Pubmed, EMBASE, Web of Science, and the Cochrane Library was performed from inception until March 26, 2019. Only randomized controlled trials which assessed oral, non-pharmacological interventions (e.g. diets, vitamins, oils, herbal remedies, fatty acids, supplements, etc.) in adult patients with rheumatoid arthritis, that presented clinically-relevant outcomes (defined as pain, fatigue, disability, joint counts, and/or disease indices) were included in our meta-analysis. Data were analyzed as mean differences between active and placebo and forest plots were performed. Heterogeneity was evaluated using I-squared statistics while funnel plots and Cochrane's risk of bias assessment evaluated bias.

RESULTS

8170 articles were identified in the search and 51 were RCTs were included. The mean difference in DAS28 was significantly improved in experimental group treated with diet (-0.46 [-0.91, -0.02], p = 0.04), zinc sulfate, copper sulphate, selenium, potassium, lipoic acid, turmeric, pomegranate extract, chamomile, and cranberry extract supplements (-0.77 [-1.17, -0.38], p < 0.001), A, B6, C, D, E, and K vitamins (-0.52 [-0.74, -0.29], p < 0.001), and fatty acids (-0.19 [-0.36, -0.01], p = 0.03). Other clinical metrics such as SJC, TJC, HAQ, SDAI, ACR20, and self-reported pain were decreased in the treatment groups. There was significant reporting bias in the studies.

CONCLUSION

Some non-pharmacological therapies may modestly improve some clinical outcomes in patients with rheumatoid arthritis. Many identified studies lacked full reporting. Further clinical trials that are well-designed, adequately powered, and sufficiently report ACR improvement criteria or EULAR response criteria outcomes are needed to confirm the efficacy of these therapies.

Effects of Microecological Regulators on Rheumatoid Arthritis: A Systematic Review and Meta-Analysis of Randomized, Controlled Trials

In this study, the available data from published randomized, controlled trials (RCTs) of the use of intestinal microecological regulators as adjuvant therapies to relieve the disease activity of rheumatoid arthritis (RA) are systematically compared. An English literature search was performed using PubMed, Embase, Scopus, Web of Science and the Cochrane Central Registry of Controlled Trials and supplemented by hand searching reference lists. Three independent reviewers screened and assessed the quality of the studies. Among the 2355 citations identified, 12 RCTs were included. All data were pooled using a mean difference (MD) with a 95% CI. The disease activity score (DAS) showed a significant improvement following microecological regulators treatment (MD (95% CI) of -1.01 (-1.81, -0.2)). A borderline significant reduction in the health assessment questionnaire (HAQ) scores was observed (MD (95% CI) of -0.11 (-0.21, -0.02)). We also confirmed the known effects of probiotics on inflammatory parameters such as the C-reactive protein (CRP) (MD -1.78 (95% CI -2.90, -0.66)) and L-1β (MD -7.26 (95% CI -13.03, -1.50)). No significant impact on visual analogue scale (VAS) of pain and erythrocyte sedimentation rate (ESR) reduction was observed. Intestinal microecological regulators supplementation could decrease RA activity with a significant effect on DAS28, HAQ and inflammatory cytokines. Nevertheless, these findings need further confirmation in large clinical studies with greater consideration of the confounding variables of age, disease duration, and individual medication regimens.

Quercetin modulates the liver metabolic profile in a chronic unpredictable mild stress rat model based on metabolomics technology

Depression is the most prevalent psychiatric disease, and its pathogenesis is still unclear. Currently, studies on the pathogenesis of depression are mainly focused on the brain. The liver can modulate brain function via the liver-brain axis, indicating that the liver plays an important role in the development of depression. This study aims to explore the protective effect of quercetin against chronic unpredictable mild stress (CUMS)-induced metabolic changes and the corresponding mechanisms in the rat liver based on untargeted metabolomics technology. In this study, 96 male rats were divided into six groups: control, different doses of quercetin (10 mg per kg bw or 50 mg per kg bw), CUMS, and CUMS + different doses of quercetin. After 8 weeks of CUMS modeling, the liver samples were collected for metabolomics analysis. A total of 17 altered metabolites were identified, including D-glutamic acid, S-adenosylmethionine, lithocholylglycine, L-homocystine, prostaglandin PGE2, leukotriene E4, cholic acid, 5-methyltetrahydrofolic acid, taurochenodeoxycholic acid, S-adenosylhomocysteine, deoxycholic acid, folic acid, L-methionine, leukotriene C5, estriol-17-glucuronide, PE, and PC, indicating that methionine metabolism, bile acid metabolism, and phosphatidylcholine biosynthesis are the major pathways involved in CUMS-induced hepatic metabolic disorders. Hepatic methylation damage may play a role in the pathophysiology of depression, as evidenced by the first discovery of the abnormality of hepatic methionine metabolism. Abnormal changes in hepatic bile acids may provide stronger evidence for depression pathogenesis involving the microbiota-gut-brain axis, suggesting that the liver is involved in depression development and may be a treatment target. The quercetin treatment alleviated the CUMS-induced liver metabolism disorder, suggesting that quercetin may protect against depression by regulating liver metabolism.

Quercetin prevents osteoarthritis progression possibly via regulation of local and systemic inflammatory cascades

Due to the lack of effective treatments, osteoarthritis (OA) remains a challenge for clinicians. Quercetin, a bioflavonoid, has shown potent anti-inflammatory effects. However, its effect on preventing OA progression and the underlying mechanisms are still unclear. In this study, Sprague-Dawley male rats were divided into five groups: control group, OA group (monosodium iodoacetate intra-articular injection), and three quercetin-treated groups. Quercetin-treated groups were treated with intragastric quercetin once a day for 28 days. Gross observation and histopathological analysis showed cartilage degradation and matrix loss in the OA group. High-dose quercetin-group joints showed failure in OA progression. High-dose quercetin inhibited the OA-induced expression of MMP-3, MMP-13, ADAMTS4, and ADAMTS5 and promoted the OA-reduced expression of aggrecan and collagen II. Levels of most inflammatory cytokines and growth factors tested in synovial fluid and serum were upregulated in the OA group and these increases were reversed by high-dose quercetin. Similarly, subchondral trabecular bone was degraded in the OA group and this effect was reversed in the high-dose quercetin group. Our findings indicate that quercetin has a protective effect against OA development and progression possibly via maintaining the inflammatory cascade homeostasis. Therefore, quercetin could be a potential therapeutic agent to prevent OA progression in risk groups.

Structural Insights into Plasticity and Discovery of Flavonoid Allosteric Inhibitors of Flavivirus NS2B–NS3 Protease

Flaviviruses are among the most critical pathogens in tropical regions; they cause various severe diseases in developing countries but are not restricted to these countries. The development of antiviral therapeutics is crucial for managing flavivirus outbreaks. Ten proteins are encoded in the flavivirus RNA. The N2B–NS3pro protein complex plays a fundamental role in flavivirus replication and is a promising drug target; however, no flavivirus protease inhibitors have progressed to the preclinical stage. This study analyzed the structural models and plasticity of the NS2B–NS3pro protein complex of five medically important non-dengue flaviviruses (West Nile, Rocio, Ilhéus, yellow fever, and Saint Louis encephalitis). The flavonoids amentoflavone, tetrahydrorobustaflavone, and quercetin were selected for their exceptional binding energies as potential inhibitors of the NS2B–NS3pro protein complex. AutoDock Vina results ranged from −7.0 kcal/mol to −11.5 kcal/mol and the compounds preferentially acted non-competitively. Additionally, the first structural model for the NS2B–NS3pro protein complex was proposed for Ilhéus and Rocio viruses. The NS2B–NS3pro protease is an attractive molecular target for drug development. The three identified natural flavonoids showed great inhibitory potential against the viral species. Nevertheless, further in silico and in vitro studies are required to obtain more information regarding NS2B–NS3pro inhibition by these flavonoids and their therapeutic potential.

LC-HRMS for the Identification of Quercetin and Its Derivatives in Spiraea hypericifolia (Rosaceae) and Anatomical Features of Its Leaves

Spiraea hypericifolia L. is affiliated with the section Chamaedryon Ser. of the genus Spiraea L. (Rosaceae). Similar to many other Spiraea species, S. hypericifolia most often accumulates flavonols among other flavonoids, in particular quercetin and its derivatives. An ethanol-water extract from the aerial part of S. hypericifolia collected in the vicinity of the Ilyichovo settlement (Krasnoyarsk Krai, Russia) was analyzed by liquid chromatography with high-resolution mass spectrometry. Primary and secondary metabolites were found in the extract; structural interpretation consistent with quercetin and its derivatives was proposed for 10 of them. Major compounds were various glycosides of quercetin containing glucose (four compounds), galactose (one compound), xylose (two compounds), arabinose (one compound), or rutinose (one compound) as a carbohydrate residue. Isorhamnetin and 3-O-methylquercetin-3'-O-β-D-glucopyranoside were identified among methyl-containing compounds. The latter compound and reynoutrin, rhamnetin-3-O-β-D-xylopyranosyl-β-D-glucopyranoside, and quercetin-3-O-(6″-O-malonyl)-β-D-glucoside have not been previously found in S. hypericifolia. Data on the presence of quercetin and its derivatives in the extract of S. hypericifolia expand the understanding of the possible practical use of this plant. In addition, the microscopic features of S. hypericifolia leaves were studied. The diagnostic features of the leaf blade necessary for the authentication of raw materials were revealed: straight-walled epidermis cells, stomata located on both sides of the leaf blade (amphistomatic type), two types of trichomes, and wrinkled cuticula with nodi. The main anatomical diagnostic features of the leaves of S. hypericifolia were determined, which makes it possible to assess the authenticity of the raw material.

The therapeutic potential of quercetin for cigarette smoking-induced chronic obstructive pulmonary disease: a narrative review

Quercetin is a flavonoid with antioxidant and anti-inflammatory properties. Quercetin has potentially beneficial therapeutic effects for several diseases, including cigarette smoking-induced chronic obstructive pulmonary disease (CS-COPD). Many studies have shown that quercetin's antioxidant and anti-inflammatory properties have positive therapeutic potential for CS-COPD. In addition, quercetin's immunomodulatory, anti-cellular senescence, mitochondrial autophagy-modulating, and gut microbiota-modulating effects may also have therapeutic value for CS-COPD. However, there appears to be no review of the possible mechanisms of quercetin for treating CS-COPD. Moreover, the combination of quercetin with common therapeutic drugs for CS-COPD needs further refinement. Therefore, in this article, after introducing the definition and metabolism of quercetin, and its safety, we comprehensively presented the pathogenesis of CS-COPD related to oxidative stress, inflammation, immunity, cellular senescence, mitochondrial autophagy, and gut microbiota. We then reviewed quercetin's anti-CS-COPD effects, performed by influencing these mechanisms. Finally, we explored the possibility of using quercetin with commonly used drugs for treating CS-COPD, providing a basis for future screening of excellent drug combinations for treating CS-COPD. This review has provided meaningful information on quercetin's mechanisms and clinical use in treating CS-COPD.

Efficacy and safety of dietary polyphenols in rheumatoid arthritis: A systematic review and meta-analysis of 47 randomized controlled trials

OBJECTIVE

To evaluate safety and efficacy of dietary polyphenols in the treatment of rheumatoid arthritis (RA).

METHODS

CNKI, Pubmed, Cochrane library, Embase were searched to collect randomized controlled trials (RCTs) of dietary polyphenols in the treatment of RA. The databases were searched from the time of their establishment to November 8nd, 2022. After 2 reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies, Meta-analysis was performed using RevMan5.4 software.

RESULTS

A total of 49 records (47 RCTs) were finally included, involving 3852 participants and 15 types of dietary polyphenols (Cinnamon extract, Cranberry extract, Crocus sativus L. extract, Curcumin, Garlic extract, Ginger extract, Hesperidin, Olive oil, Pomegranate extract, Puerarin, Quercetin, Resveratrol, Sesamin, Tea polyphenols, Total glucosides of paeony). Pomegranate extract, Resveratrol, Garlic extract, Puerarin, Hesperidin, Ginger extract, Cinnamon extract, Sesamin only involve in 1 RCT. Cranberry extract, Crocus sativus L. extract, Olive oil, Quercetin, Tea polyphenols involve in 2 RCTs. Total glucosides of paeony and Curcumin involve in more than 3 RCTs. These RCTs showed that these dietary polyphenols could improve disease activity score for 28 joints (DAS28), inflammation levels or oxidative stress levels in RA. The addition of dietary polyphenols did not increase adverse events.

CONCLUSION

Dietary polyphenols may improve DAS28, reduce C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and improve oxidative stress, etc. However, more RCTs are needed to verify or modify the efficacy and safety of dietary polyphenols.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/, identifier CRD42022315645.

Nutrients and rheumatoid arthritis: From the perspective of neutrophils

Neutrophils are considered as core immune cells involve in the early stage of rheumatoid arthritis (RA) and participate in the disease progression. The underlining mechanisms include the elevated chemotaxis and infiltration of neutrophils, the increase in the reactive oxygen species and the promotion of neutrophil extracellular traps formation. Accumulating studies demonstrated the important role of nutrients intake played in the initiation and progression of RA. This study summarized the effects of several macronutrients and micronutrients on regulating RA through the modulation of activated neutrophils and appealed for a healthy diet in RA-risk individuals as well as RA patients.

Luteolin: A promising natural agent in management of pain in chronic conditions

Pain due to chronic conditions is a frequent and insufficiently addressed problem. Current drug options for pain management (either in cases of chronic inflammatory conditions or neuropathy) do not adequately treat pain. Moreover, they are associated with important adverse events in long term use. Luteolin is a flavonoid widely present in the plant kingdom and its sources have been assembled in a comprehensive list of this paper. Luteolin has shown in several research studies a range of pharmacological properties; anti-inflammatory, antioxidant, neuroprotective, and analgesic. In this article, we summarize the effects and potential benefits from introducing luteolin as an adjuvant agent in established protocols for pain management. We review the most indicative in vivo and in vitro evidence of how luteolin can target the molecular pathways involved in pathogenesis of chronic inflammatory and neuropathic pain. The data reviewed strongly support luteolin's promising benefits in pain management and raise the need for further clinical trials that can establish its role in clinical practice.

Antifungal and Immunomodulatory Ingredients from Traditional Chinese Medicine

Fungal infections have become a growing public health challenge due to the clinical transmission of pathogenic fungi. The currently available antifungal drugs leave very limited choices for clinical physicians to deal with such situation, not to mention the long-standing problems of emerging drug resistance, side effects and heavy economic burdens imposed to patients. Therefore, new antifungal drugs are urgently needed. Screening drugs from natural products and using synthetic biology strategies are very promising for antifungal drug development. Chinese medicine is a vast library of natural products of biologically active molecules. According to traditional Chinese medicine (TCM) theory, preparations used to treat fungal diseases usually have antifungal and immunomodulatory functions. This suggests that if antifungal drugs are used in combination with immunomodulatory drugs, better results may be achieved. Studies have shown that the active components of TCM have strong antifungal or immunomodulatory effects and have broad application prospects. In this paper, the latest research progress of antifungal and immunomodulatory components of TCM is reviewed and discussed, hoping to provide inspiration for the design of novel antifungal compounds and to open up new horizons for antifungal treatment strategies.

The Role of Nutrition on Meta-inflammation: Insights and Potential Targets in Communicable and Chronic Disease Management

PURPOSE OF REVIEW

Chronic low-grade inflammation may contribute to the onset and progression of communicable and chronic diseases. This review examined the effects and eventual mediation roles of different nutritional factors on inflammation.

RECENT FINDINGS

Potential nutritional compounds influencing inflammation processes include macro and micronutrients, bioactive molecules (polyphenols), specific food components, and culinary ingredients as well as standardized dietary patterns, eating habits, and chrononutrition features. Therefore, research in this field is still required, taking into account critical aspects of heterogeneity including type of population, minimum and maximum intakes and adverse effects, cooking methods, physiopathological status, and times of intervention. Moreover, the integrative analysis of traditional variables (age, sex, metabolic profile, clinical history, body phenotype, habitual dietary intake, physical activity levels, and lifestyle) together with individualized issues (genetic background, epigenetic signatures, microbiota composition, gene expression profiles, and metabolomic fingerprints) may contribute to the knowledge and prescription of more personalized treatments aimed to improving the precision medical management of inflammation as well as the design of anti-inflammatory diets in chronic and communicable diseases.

Quercetin alleviates ferroptosis accompanied by reducing M1 macrophage polarization during neutrophilic airway inflammation

Ferroptosis is a kind of regulated cell death, supporting the pathological process of lung inflammation, including asthma. Quercetin (QCT), a kind of natural dietary flavonoid, exerts anti-inflammatory and anti-ferroptosis effects in various diseases. However, the role of QCT in ferroptosis-associated airway inflammation of neutrophilic asthma remains to be described. Our study aimed to investigate the therapeutic effects of QCT on neutrophilic airway inflammation of asthma. Ferrostatin-1 (Fer-1), as a kind of ferroptosis inhibitor, was used to demonstrate whether neutrophilic airway inflammation of asthma relied on ferroptosis. In our study, the alleviation effect of QCT on neutrophilic airway inflammation was similar to Fer-1. Moreover, the significantly decreased levels of ferroptosis anti-oxidant protein (GPX4 and SLC7A11), increased malondialdehyde (MDA) levels, upregulated levels of 4-hydroxynonenal (4-HNE) expression by immunohistochemistry, and distorted mitochondria morphological changes in the lung tissues suggested lung ferroptosis in neutrophilic airway inflammation, which could be reversed by QCT treatment. In vitro experiments showed that QCT reduced LPS-induced ferroptosis through upregulating cell viability and levels of ferroptosis anti-oxidant protein (SLC7A11 and GPX4), reducing inflammatory cytokines, and decreasing the levels of MDA. Furthermore, ferroptosis was accompanied by enhancing M1 phenotype in neutrophilic airway inflammation, and QCT suppressed ferroptosis by inhibiting the pro-inflammatory M1 profile in vitro and in vivo, just as Fer-1 did. In conclusion, our study found that QCT ameliorated ferroptosis-associated neutrophilic airway inflammation accompanied by inhibiting M1 macrophage polarization. QCT may be a promising ferroptosis inhibitor for neutrophilic airway inflammation.