Quercetin Attenuates Quinocetone-Induced Cell Apoptosis In Vitro by Activating the P38/Nrf2/HO-1 Pathway and Inhibiting the ROS/Mitochondrial Apoptotic Pathway

Colistin Induces Oxidative Stress and Apoptotic Cell Death through the Activation of the AhR/CYP1A1 Pathway in PC12 Cells

Colistin is commonly regarded as the "last-resort" antibiotic for combating life-threatening infections caused by multidrug-resistant (MDR) gram-negative bacteria. Neurotoxicity is a potential adverse event associated with colistin application in clinical settings, yet the exact molecular mechanisms remain unclear. This study examined the detrimental impact of colistin exposure on PC12 cells and the associated molecular mechanisms. Colistin treatment at concentrations of 0-400 μM decreased cell viability and induced apoptotic cell death in both time- and concentration-dependent manners. Exposure to colistin triggered the production of reactive oxygen species (ROS) and caused oxidative stress damage in PC12 cells. N-acetylcysteine (NAC) supplementation partially mitigated the cytotoxic and apoptotic outcomes of colistin. Evidence of mitochondrial dysfunction was observed through the dissipation of membrane potential. Additionally, colistin treatment upregulated the expression of AhR and CYP1A1 mRNAs in PC12 cells. Pharmacological inhibition of AhR (e.g., using α-naphthoflavone) or intervention with the CYP1A1 gene significantly decreased the production of ROS induced by colistin, subsequently lowering caspase activation and cell apoptosis. In conclusion, our findings demonstrate, for the first time, that the activation of the AhR/CYP1A1 pathway contributes partially to colistin-induced oxidative stress and apoptosis, offering insights into the cytotoxic effects of colistin.

Active targeting microemulsion-based thermosensitive hydrogel against periodontitis by reconstructing Th17/Treg homeostasis via regulating ROS-macrophages polarization cascade

Periodontitis is a multifactorial inflammatory disease characterized by severe alveolar bone damage and attachment loss. The imbalance of T help 17 (Th17) / regulatory T cells (Treg) induces excessive interleukin (IL)-17, which leads to alveolar bone damage and aggravates the development of periodontitis. Therefore, we proposed a therapeutic strategy to restore Th17/Treg homeostasis by interfering reactive oxygen species (ROS)-macrophage polarization cascade using active targeting microemulsions-based thermosensitive hydrogel. Folic acid-modified quercetin-loaded microemulsions (FA-Qu-MEs) were dispersed in poloxamer 407 and poly(N-isopropylacrylamide) matrix of hydrogel (FA-Qu-MEs@Gel). FA-Qu-MEs@Gel could be locally injected into the periodontal pocket and sustainedly release drugs. FA-Qu-MEs exhibited excellent ROS scavenging potency by targeting macrophages, resulting M1 phenotype macrophage from to M2 phenotype macrophage. Subsequently, the phenotypic changes of macrophages lead to decreased expression of IL-6 and tumor necrosis factor-α, which inhibited activated Th17, while IL-10 secreted by M2 macrophages promoted Treg differentiation. Finally, the restored Th17/Treg homeostasis reduced the level of IL-17 to accelerate alveolar bone regeneration. This study deigns a novel system that promote alveolar bone regeneration by remodeling Th17/Treg homeostasis via regulating ROS-macrophages polarization cascade for periodontitis treatment.

Therapeutic efficacy and pharmacological mechanism of Yindan Xinnaotong soft capsule on acute ischemic stroke: a meta-analysis and network pharmacology analysis

Yindan Xinnaotong soft capsule (YDXNT), a traditional Chinese medicine preparation, has shown a promising effect in the treatment of acute ischemic stroke (AIS). The goal of this study was to investigate the therapeutic effects and pharmacological mechanisms of YDXNT on AIS. Randomized controlled trials were searched and screened. Review Manager 5.4 was used for a meta-analysis. Active ingredients and targets of YDXNT were extracted from the Traditional Chinese Medicine Systems Pharmacology Database, Bioinformatics Analysis Tool for Molecular mechANism of Traditional Chinese Medicine, and Encyclopaedia of Traditional Chinese Medicine. AIS-related targets were retrieved from GeneCards, OMIM, and DrugBank databases. We constructed PPI and ingredient-target networks, performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses, and conducted molecular docking. The YDXNT group had a higher total effective rate and a higher Barthel Index score. YDXNT reduced the low-density lipoprotein cholesterol and the whole blood viscosity at high and shear rates. Our study identified 313 ingredients and 1196 common targets. The key ingredients were mainly quercetin, neocryptotanshinone II, miltionone I, neotanshinone C, and tanshiquinone B, and the key targets were mainly SRC, MAPK3, AKT1, MAPK1, and JUN. GO analysis showed that the core targets mainly involved in atherosclerosis and neural apoptosis. The core pathways were lipid and atherosclerosis, PI3K-Akt, MAPK, and other pathways. Key ingredients exhibited robust binding interactions with core targets. YDXNT could effectively improve the total effective rate, ability of daily life, blood lipids, and blood viscosity. Antiatherosclerotic and neuroprotective effects are the main pharmacological mechanisms.Registration number: CRD42023400127.

Therapeutic detoxification of quercetin for aflatoxin B1-related toxicity: Roles of oxidative stress, inflammation, and metabolic enzymes

Aflatoxins (AFTs), a type of mycotoxin mainly produced by Aspergillus parasiticus and Aspergillus flavus, could be detected in food, feed, Chinese herbal medicine, grain crops and poses a great threat to public health security. Among them, aflatoxin B1 (AFB1) is the most toxic one. Exposure to AFB1 poses various health risks to both humans and animals, including the development of chronic inflammatory diseases, cardiovascular diseases, neurodegenerative diseases, and cancer. The molecular mechanisms underlying these risks are intricate and dependent on specific contexts. This review primarily focuses on summarizing the protective effects of quercetin, a natural phenolic compound, in mitigating the toxic effects induced by AFB1 in both in vitro experiments and animal models. Additionally, the review explores the molecular mechanisms that underlie these protective effects. Quercetin has been demonstrated to not only have the direct inhibitory action on the production of AFTs from Aspergillus, both also possess potent ameliorative effects against AFB1-induced cytotoxicity, hepatotoxicity, and neurotoxicity. These effects are attributed to the inhibition of oxidative stress, mitochondrial dysfunction, mitochondrial apoptotic pathway, and inflammatory response. It could also directly target several metabolic enzymes (i.e., CYP3As and GSTA1) to reduce the production of toxic metabolites of AFB1 within cells, then reduce AFB1-induced cytotoxicity. In conclusion, this review highlights quercetin is a promising detoxification agent for AFB1. By advancing our understanding of the protective mechanisms offered by quercetin, we aim to contribute to the development of effective detoxification agents against AFB1, ultimately promoting better health outcomes.

Systematic Pharmacology and Experimental Validation to Reveal the Alleviation of Astragalus membranaceus Regulating Ferroptosis in Osteoarthritis

Background

Astragalus membranaceus (AM) shows promise as a therapeutic agent for osteoarthritis (OA), a debilitating condition with high disability rates. OA exacerbation is linked to chondrocyte ferroptosis, yet the precise pharmacological mechanisms of AM remain unclear.

Methods

We validated AM's protective efficacy in an anterior cruciate ligament transection (ACLT) mouse model of OA. The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) database was utilized to identify AM's active components and their targets. FerrDb (a database for regulators and markers of ferroptosis and ferroptosis-disease associations) pinpointed ferroptosis-related targets, while GeneCards, Online Mendelian Inheritance in Man (OMIM), Pharmacogenomics Knowledgebase (PharmGKB), Therapeutic Target Database (TTD), and DrugBank sourced OA-related genes. Molecular docking analysis further validated these targets. Ultimately, the validation of the results was accomplished through in vitro experiments.

Results

AM exhibited anabolic effects and suppressed catabolism in OA chondrocytes. Network pharmacology identified 19 common genes, and molecular docking suggested quercetin, an AM constituent, interacts with key proteins like HO-1 and NRF2 to inhibit chondrocyte ferroptosis. In vitro experiments confirmed AM's ability to modulate the NRF2/HO-1 pathway via quercetin, mitigating chondrocyte ferroptosis.

Conclusion

This study elucidates how AM regulates chondrocyte ferroptosis, impacting OA progression, providing a theoretical basis and experimental support for AM's scientific application.

Quercetin attenuates cerebral ischemic injury by inhibiting ferroptosis via Nrf2/HO-1 signaling pathway

AIMS

Ischemic stroke is a severe cerebrovascular disease in which neuronal death continually occurs through multiple forms, including apoptosis, autophagy, pyroptosis and ferroptosis. Quercetin (QRC), as a natural flavonoid compound, has been reported to have pharmacological effects on ischemic injury accompanied by unclear anti-ferroptotic mechanisms. This study is designed to investigate the therapeutic effects of QRC against ferroptosis in ischemic stroke.

MATERIALS AND METHODS

In vivo, the model of MCAO rats were used to assess the protective effect of QRC on cerebral ischemic. Additionally, we constructed oxidative stressed and ferroptotic cell models to explore the effects and mechanisms of QRC on ferroptosis. The related proteins were analysed by western blotting, immunohistochemical and immunofluorescence techniques.

RESULTS

The experiments demonstrated that QRC improves neurological deficits, infarct volume, and pathological features in MCAO rats, also increased the viability of HT-22 cells exposed to H2O2 and erastin. These results, including MDA, SOD, GSH, ROS levels and iron accumulation, indicated that QRC suppresses the generation of lipid peroxides and may involve in the regulatory of ferroptosis. Both in vitro and in vivo, QRC was found to inhibit ferroptosis by up-regulating GPX4 and FTH1, as well as down-regulating ACSL4. Furthermore, we observed that QRC enhances the nuclear translocation of Nrf2 and activates the downstream antioxidative proteins. Importantly, the effect of QRC on ferroptosis can be reversed by the Nrf2 inhibitor ML385.

CONCLUSIONS

This study provides evidence that QRC has a neuroprotective effect by inhibiting ferroptosis, demonstrating the therapeutic potential for cerebral ischemic stroke.

Advance in the pharmacological effects of quercetin in modulating oxidative stress and inflammation related disorders

Numerous pharmacological effects of quercetin have been illustrated, including antiinflammation, antioxidation, and anticancer properties. In recent years, the antioxidant activity of quercetin has been extensively reported, in particular, its impacts on glutathione, enzyme activity, signaling transduction pathways, and reactive oxygen species (ROS). Quercetin has also been demonstrated to exert a striking antiinflammatory effect mainly by inhibiting the production of cytokines, reducing the expression of cyclooxygenase and lipoxygenase, and preserving the integrity of mast cells. By regulating oxidative stress and inflammation, which are regarded as two critical processes involved in the defense and regular physiological operation of biological systems, quercetin has been validated to be effective in treating a variety of disorders. Symptoms of these reactions have been linked to degenerative processes and metabolic disorders, including metabolic syndrome, cardiovascular, neurodegeneration, cancer, and nonalcoholic fatty liver disease. Despite that evidence demonstrates that antioxidants are employed to prevent excessive oxidative and inflammatory processes, there are still concerns regarding the expense, accessibility, and side effects of agents. Notably, natural products, especially those derived from plants, are widely accessible, affordable, and generally safe. In this review, the antioxidant and antiinflammatory abilities of the active ingredient quercetin and its application in oxidative stress-related disorders have been outlined in detail.

A review of how the saffron (Crocus sativus) petal and its main constituents interact with the Nrf2 and NF-κB signaling pathways

The primary by-product of saffron (Crocus sativus) processing is saffron petals, which are produced in large quantities but are discarded. The saffron petals contain a variety of substances, including alkaloids, anthocyanins, flavonoids, glycosides, kaempferol, and minerals. Pharmacological investigations revealed the antibacterial, antidepressant, antidiabetic, antihypertensive, antinociceptive, antispasmodic, antitussive, hepatoprotective, immunomodulatory, and renoprotective properties of saffron petals, which are based on their antioxidant, anti-inflammatory, and antiapoptotic effects. The nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway protects against oxidative stress, carcinogenesis, and inflammation. Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB) is a protein complex involved in approximately all animal cells and participates in different biological procedures such as apoptosis, cell growth, development, deoxyribonucleic acid (DNA) transcription, immune response, and inflammation. The pharmacological properties of saffron and its compounds are discussed in this review, along with their associated modes of action, particularly the Nrf2 and NF-ĸB signaling pathways. Without considering a time constraint, our team conducted this review using search engines or electronic databases like PubMed, Scopus, and Web of Science. Saffron petals and their main constituents may have protective effects in numerous organs such as the brain, colon, heart, joints, liver, lung, and pancreas through several mechanisms, including the Nrf2/heme oxygenase-1 (HO-1)/Kelch-like ECH-associated protein 1 (Keap1) signaling cascade, which would then result in its antioxidant, anti-inflammatory, antiapoptotic, and therapeutic effects.

Angelica Sinensis polysaccharide antagonizes 5-Fluorouracil-induced spleen injury and dysfunction by suppressing oxidative stress and apoptosis

Angelica Sinensis polysaccharide (ASP), the main active component of Angelica sinensis, possesses antioxidative and anti-apoptotic properties. In this study, we have investigated the antagonistic effect of ASP on 5-FU-induced injury of mouse spleen in vivo and splenocytes in vitro, and its possible mechanism. Our results showed that ASP inhibited 5-FU-induced decreases in spleen weight and organ index in mice, restored the number of peripheral blood leukocytes and lymphocytes, repaired spleen structure disorder and functional impairment, rescued serum IL-2, IL-6, and IFN-γ levels, and relieved 5-FU-induced mitochondrial swelling， reduced the oxidant accumulation including MDA and ROS, whereas increasing the activities of GSH, SOD and CAT. The mechanism may be related to ASP downregulation of Keap1 protein expression thus motivating the nuclear translocation of Nrf2. Furthermore, ASP alleviated the apoptosis of spleens in vivo and splenocytes in vitro, and reactivated PI3K / AKT signalling. In conclusion, the protective effect of ASP on spleens and splenocytes may be related to the reduction of oxidative stress and apoptosis via reactivation of Nrf2 and PI3K/AKT pathways. This study has provided a new protective agent for minimizing the spleen injury caused by 5-FU and a new idea for improving the prognosis of chemotherapy patients.

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.

Nootkatone Supplementation Attenuates Carbon Tetrachloride Exposure-Induced Nephrotoxicity in Mice

Nootkatone (NKT), a major ingredient of Alpinia oxyphylla, exhibited potential nephroprotective effects; however, the precise molecular mechanisms remain poorly understood. This study aimed to study the nephroprotective effects of NKT and the underlying mechanisms in a mouse model. Our results showed that NKT pretreatment at the doses of 5, 10, and 20 mg/kg per day for 7 days significantly attenuates carbon tetrachloride (CCl₄)-induced increases of serum BUN and CRE and kidney pathology injury. NKT pretreatment also markedly inhibited oxidative stress, inflammatory response, and the activation of caspases-9 and -3 in kidneys of mice exposed to CCl₄. Meanwhile, NKT pretreatment downregulated the expression of NOX4, IL-1β, IL-6, and TNF-α proteins and NO levels in the kidney tissues. Moreover, NKT pretreatment upregulated the expression of Nrf2 and HO-1 mRNAs, and downregulated the expression of NF-κB, IL-1β, IL-6, TNF-α, and iNOS mRNAs in the kidneys of mice, compared to those in the CCl₄ alone treatment group. In conclusion, our results reveal that NKT supplementation could protect against CCl₄ exposure-induced oxidative stress and inflammatory response in the kidneys by inhibiting NOX4 and NF-κB pathways and activating the Nrf2/HO-1 pathway. Our current study highlights the therapeutic application of NKT for kidney diseases.

Nootkatone Supplementation Ameliorates Carbon Tetrachloride-Induced Acute Liver Injury via the Inhibition of Oxidative Stress, NF-κB Pathways, and the Activation of Nrf2/HO-1 Pathway

Acute liver injury is a type of liver diseases, and it has raised concerns worldwide due to the lack of effective therapies. The aim of this study is to investigate the protective effects of nootkatone (NOOT) on carbon tetrachloride (CCl₄)-caused acute liver injury in mice. Mice were randomly divided into control, CCl₄ model, NOOT, and NOOT (5, 10, and 20 mg/kg/day) plus CCl₄ groups, respectively. Mice in the CCl₄ plus NOOT groups were orally administrated with NOOT at 5, 10, and 20 mg/kg/days for seven days prior to 0.3% CCl₄ injection at 10 mL/kg body weight, respectively. Our results showed that NOOT supplementation significantly ameliorated CCl₄-induced increases of serum AST and ALT levels, hepatocyte necrosis, inflammatory response, oxidative stress, and caspases-9 and -3 activities in the livers of mice. Moreover, NOOT supplementation significantly upregulated the expression of Nrf2 and HO-1 mRNAs but downregulated the expression of NF-κB mRNAs and the levels of IL-1β, IL-6, and TNF-α proteins in the liver tissues, compared to those in the CCl₄ model group. In conclusion, for the first time, our results reveal that NOOT could offer protective effects against CCl₄-caused oxidative stress and inflammatory response via the opposite regulation of Nrf2/HO-1 pathway and NF-κB pathway.