Esculetin, a natural dihydroxy coumarin derived from the Chinese herbal medicine Cortex Fraxini, has demonstrated significant pharmacological activities, including anticancer properties. Ferroptosis, an iron-dependent form of regulated cell death, has garnered considerable attention due to its lethal effect on tumor cells. However, the exact role of ferroptosis in esculetin-mediated anti-hepatocellular carcinoma (HCC) effects remains poorly understood. This study investigated the impact of esculetin on HCC cells both in vitro and in vivo. The findings indicate that esculetin effectively inhibited the growth of HCC cells. Importantly, esculetin promoted the accumulation of intracellular Fe²⁺, leading to an increase in ROS production through the Fenton reaction. This event subsequently induced lipid peroxidation (LPO) and triggered ferroptosis within the HCC cells. The occurrence of ferroptosis was confirmed by the elevation of malondialdehyde (MDA) levels, the depletion of glutathione peroxidase (GSH-Px) activity, and the disruption of mitochondrial morphology. Notably, the inhibitor of ferroptosis, ferrostatin-1 (Fer-1), attenuated the anti-tumor effect of esculetin in HCC cells. Furthermore, the findings revealed that esculetin inhibited the Nrf2-xCT/GPx4 axis signaling in HCC cells. Overexpression of Nrf2 upregulated the expression of downstream SLC7A11 and GPX4, consequently alleviating esculetin-induced ferroptosis. In conclusion, this study suggests that esculetin exerts an anti-HCC effect by inhibiting the activity of the Nrf2-xCT/GPx4 axis, thereby triggering ferroptosis in HCC cells. These findings may contribute to the potential clinical use of esculetin as a candidate for HCC treatment.
Umbelliferones/administration & dosage* ; Ferroptosis/drug effects* ; Carcinoma, Hepatocellular/physiopathology* ; NF-E2-Related Factor 2/genetics* ; Humans ; Liver Neoplasms/physiopathology* ; Phospholipid Hydroperoxide Glutathione Peroxidase/genetics* ; Animals ; Cell Line, Tumor ; Mice ; Amino Acid Transport System y+/genetics* ; Mice, Inbred BALB C ; Male ; Signal Transduction/drug effects* ; Lipid Peroxidation/drug effects* ; Reactive Oxygen Species/metabolism* ; Mice, Nude

OBJECTIVES: This study aims to investigate the impact of glutathione S-transferase (GST) on the environmental adaptability of Streptococcus mutans (S. mutans). METHODS: A GST knockout strain ΔgsT was constructed. Transcriptomic sequencing was performed to analyze the gene expression differences between the wild-type S. mutans UA159 and its GST knockout strain ΔgsT. Comprehensive functional assessments, including acid tolerance assays, hydrogen peroxide challenge assays, nutrient limitation growth assays, and fluorescence in situ hybridization, were conducted to evaluate the acid tolerance, antioxidant stress resistance, growth kinetics, and interspecies competitive ability of ΔgsT within plaque biofilms. RESULTS: Compared with the wild-type S. mutans, 198 genes in ΔgsT were significantly differentially expressed and enriched in pathways related to metabolism, stress response, and energy homeostasis. The survival rate of ΔgsT in acid tolerance assays was markedly reduced (P<0.01). After 15 min of hydrogen peroxide challenge, the survival rate of ΔgsT decreased to 38.12% (wild type, 71.75%). Under nutrient-limiting conditions, ΔgsT exhibited a significantly lower final OD₆₀₀ value than the wild-type strain (P<0.05). In the biofilm competition assays, the proportion of S. mutans ΔgsT in the mixed biofilm (8.50%) was significantly lower than that of the wild type (16.89%) (P<0.05). CONCLUSIONS GST enhances the acid resistance, oxidative stress tolerance, and nutrient adaptation of S. mutans by regulating metabolism-related and stress response-related genes.
Streptococcus mutans/enzymology* ; Biofilms ; Glutathione Transferase/physiology* ; Adaptation, Physiological ; Hydrogen Peroxide/pharmacology* ; Gene Expression Regulation, Bacterial ; Oxidative Stress ; Metabolic Reprogramming

Reactive oxygen species (ROS) are major contributors to radiation therapy-induced side effects in cancer patients. A fusion antioxidant enzyme comprising glutathione S-transferase (GST), superoxide dismutase 1 (SOD1), and a transmembrane peptide has been shown to effectively mitigate ROS-induced damage. To enhance its targeting capability, the fusion protein was further modified by incorporating a matrix metalloproteinase-2/9 substrate peptide (X) and the transmembrane peptide R9, yielding the antioxidant enzyme GST-SOD1-X-R9 (GS1XR). This modification reduced its transmembrane ability in tumor cells, thereby selectively protecting normal cells from oxidative stress. However, the use of non-human GST poses potential immunogenicity risks. In this study, we employed seamless cloning technology to construct an expression vector containing the human GST gene to replace the non-human GST gene, and then expressed and purified novel fusion antioxidant enzymes GS1R and GS1XR. The protective effects of newly constructed GS1R and GS1XR against hydrogen peroxide (H₂O₂)-induced oxidative damage in L-02 cells were then evaluated using GS1 as a control. Enzymatic activity assays revealed that the specific activity of GST in GS1XR remained unchanged compared to the unmodified protein, while SOD activity was enhanced. Exposure to 200 μmol/L H₂O₂ transiently activated the nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway; however, this activation diminished after 24 h, reducing cell viability to 48.4%. Both GS1R and GS1XR effectively scavenged intracellular ROS, directly counteracting oxidative stress and promoting Nrf2 nuclear translocation, thereby activating antioxidant pathways and restoring cell viability to normal levels. The two enzymes showed comparable efficacy. In contrast, GS1, lacking transmembrane capability, was restricted to scavenging extracellular ROS and provided only limited protection. In conclusion, both novel fusion antioxidant enzymes demonstrated significant potential in safeguarding normal cells from ROS-mediated oxidative damage. The findings provide a foundation for further investigation in related field.
Humans ; Oxidative Stress/drug effects* ; Hydrogen Peroxide ; Antioxidants/metabolism* ; Glutathione Transferase/metabolism* ; Recombinant Fusion Proteins/pharmacology* ; Superoxide Dismutase-1 ; Reactive Oxygen Species/metabolism* ; Superoxide Dismutase/biosynthesis*

Objective To explore the role and mechanism of mammalian target of rapamycin (mTOR) in oxidized low-density lipoprotein (oxLDL)-induced ferroptosis in vascular smooth muscle cells (VSMCs). Methods A model of oxLDL-induced VSMC ferroptosis was established. VSMCs were co-treated with either the mTOR inhibitor rapamycin or the autophagy inducer carbonyl cyanide m-chlorophenylhydrazone (CCCP), followed by detection of autophagy and ferroptosis-related indexes. Quantitative real-time PCR and Western blot were used respectively to analyze the expression of mTOR, glutathione peroxidase 4 (GPX4), sequestosome 1 (p62), and microtubule-associated protein 1 light chain 3 (LC3). Flow cytometry was employed to assess VSMC death. C11 BODIPY fluorescent staining was used to measure cellular lipid peroxidation levels. Colorimetric assays were performed to determine the contents of malondialdehyde (MDA), ferrous ion (Fe²⁺) and glutathione (GSH). Results oxLDL significantly upregulated mTOR expression in VSMCs, while increasing p62 expression and reducing LC3 expression, thereby suppressing VSMC autophagy. Compared with oxLDL treatment alone, rapamycin co-treatment reversed oxLDL-induced VSMC ferroptosis, as characterized by reduced VSMC death, increased GPX4 expression and GSH contents, along with decreased MDA content, Fe²⁺ content and lipid peroxidation levels. Similarly, CCCP co-treatment activated autophagy characterized by reduced p62 expression and elevated LC3 expression, which subsequently alleviated oxLDL-induced ferroptosis, showing reduced VSMC death, increased GPX4 expressions and GSH contents, and decreased MDA content, Fe²⁺ content and lipid peroxidation levels. Moreover, mTOR inhibition by rapamycin significantly reversed the oxLDL-induced upregulation of p62 and downregulation of LC3. Conclusion mTOR may promote oxLDL-induced VSMC ferroptosis by suppressing autophagy.
Ferroptosis/drug effects* ; Lipoproteins, LDL/metabolism* ; TOR Serine-Threonine Kinases/physiology* ; Autophagy/drug effects* ; Muscle, Smooth, Vascular/metabolism* ; Animals ; Rats ; Myocytes, Smooth Muscle/cytology* ; Cells, Cultured ; Lipid Peroxidation/drug effects* ; Sequestosome-1 Protein/genetics* ; Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism* ; Microtubule-Associated Proteins/genetics* ; Sirolimus/pharmacology*

OBJECTIVE: To investigate the susceptibility of venetoclax-resistant acute myeloid leukemia (AML) cell lines to ferroptosis and to uncover the underlying molecular mechanisms using transcriptomic and metabolomic analysis methods. METHODS: Venetoclax-resistant AML cell lines were constructed using a low-dose concentration escalation method. The sensitivity of cells to chemotherapeutic drugs was detected by CCK-8 assay. The susceptibility of drug-resistant cell lines to ferroptosis was assessed using transcriptomic and metabolomic analysis methods. The expression of cellular GPX4 and SLC7A11 protein was detected by Western blot, and cell death and lipid peroxidation levels were measured by flow cytometry. Depmap database and TCGA cohort were applied to explore the effect of ferroptosis-related genes expression on prognosis. RESULTS: Venetoclax-resistant cell lines exhibited sensitivity to ferroptosis inducers RSL3, APR246, and sorafenib. The ferroptosis inhibitor Fer-1 partially inhibited cell death induced by these inducers. Compared with the parental cells, significant changes in metabolites and gene expression levels related to ferroptosis were observed in the resistant cell lines. In particular, deregulated expression of SLC7A11 and GPX4 may play critical role in ferroptosis susceptibility. Besides, GPX4 was identified as more important for AML cell survival and higher GPX4 expression may predict shortened overall survival, NPM1 mutant and IDH1 R132 mutation positive patients may prone to possess higher GPX4 expression. CONCLUSION Venetoclax-resistant AML cell lines remain susceptible to ferroptosis, higher GPX4 expression maybe a critical marker for poor prognosis. Regulating the expression of ferroptosis-related genes and metabolites may enhance the efficacy of venetoclax and provide new treatment options for AML patients.
Humans ; Ferroptosis ; Leukemia, Myeloid, Acute/metabolism* ; Sulfonamides/pharmacology* ; Bridged Bicyclo Compounds, Heterocyclic/pharmacology* ; Drug Resistance, Neoplasm ; Metabolomics ; Cell Line, Tumor ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Amino Acid Transport System y+/metabolism* ; Transcriptome

This study employed a mouse model of coronary artery ligation to assess the effect and mechanism of Jiming Powder on mitochondrial autophagy in mice with myocardial infarction. The mouse model of heart failure post-myocardial infarction was established by ligating the left anterior descending coronary artery. The pharmacological efficacy of Jiming Powder was evaluated through echocardiographic imaging, hematoxylin-eosin(HE) staining, and Masson staining. The levels of malondialdehyde(MDA), Fe~(2+), reduced glutathione(GSH), and superoxide dismutase(SOD) in heart tissues, as well as MDA immunofluorescence of heart tissues, were measured to assess lipid peroxidation and Fe~(2+) levels in the hearts of mice in different groups. Ferroptosis levels in the groups were evaluated using scanning electron microscopy and Prussian blue staining. Western blot analysis was conducted to detect the levels of key ferroptosis-related proteins, including nuclear factor erythroid 2-related factor 2(NRF2), ferritin heavy chain(FTH), glutathione peroxidase 4(GPX4), solute carrier family 7 member 11(SLC7A11), heme oxygenase 1(HO-1), and Kelch-like ECH-associated protein 1(KEAP1). The results showed that compared with the model group, both the high-and low-dose Jiming Powder groups exhibited significantly reduced left ventricular internal diameter in systole(LVIDs) and left ventricular internal diameter in diastole(LVIDd), while the left ventricular ejection fraction(EF) and left ventricular fractional shortening(FS) were significantly improved, effectively enhancing cardiac function in mice post-myocardial infarction. HE staining revealed that Jiming Powder attenuated myocardial inflammatory cell infiltration post-infarction, and Masson staining indicated that Jiming Powder effectively reduced fibrosis in the infarct margin area. Treatment with Jiming Powder reduced the levels of MDA and Fe~(2+), indicators of lipid peroxidation post-myocardial infarction, while increasing GSH and SOD levels, thus protecting ischemic myocardium. Western blot results demonstrated that Jiming Powder reduced KEAP1 protein accumulation, activated the NRF2/HO-1/GPX4 pathway, and up-regulated the protein expression of FTH and SLC7A11, exerting an inhibitory effect on ferroptosis. This study reveals that Jiming Powder exerts a therapeutic effect on myocardial infarction by inhibiting ferroptosis through the NRF2/HO-1/GPX4 pathway, providing a foundation for subsequent research on the pharmacological effects of Jiming Powder.
Animals ; Ferroptosis/drug effects* ; Myocardial Infarction/physiopathology* ; NF-E2-Related Factor 2/genetics* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Heme Oxygenase-1/genetics* ; Phospholipid Hydroperoxide Glutathione Peroxidase/genetics* ; Humans ; Mice, Inbred C57BL ; Signal Transduction/drug effects* ; Disease Models, Animal

OBJECTIVE: To explore the anti-photoaging properties of salvianolic acid B (Sal B). METHODS: The optimal photoaging model of human immortalized keratinocytes (HaCaT cells) were constructed by expose to ultraviolet B (UVB) radiation. The cells were divided into control, model and different concentrations of Sal B groups. Cell viability was measured via cell counting kit-8. Subsequently, the levels of oxidative stress, including reactive oxygen species (ROS), hydroxyproline (Hyp), catalase (CAT), and glutathione peroxidase (GSH-Px) were detected using the relevant kits. Silent information regulator 1 (SIRT1) protein level was detected using Western blot. The binding pattern of Sal B and SIRT1 was determined via molecular docking. RESULTS: Sal B significantly increased the viability of UVB-irradiated HaCaT cells (P<0.05 or P<0.01). Sal B effectively scavenged the accumulation of ROS induced by UVB (P<0.05 or P<0.01). In addition, Sal B modulated oxidative stress by increasing the intracellular concentrations of Hyp and CAT and the activity of GSH-Px (P<0.05 or P<0.01). The Western blot results revealed a substantial increase in SIRT1 protein levels following Sal B administration (P<0.05). Moreover, Sal B exhibited good binding affinity toward SIRT1, with a docking energy of -7.5 kCal/mol. CONCLUSION Sal B could improve the repair of photodamaged cells by alleviating cellular oxidative stress and regulating the expression of SIRT1 protein.
Humans ; Sirtuin 1/metabolism* ; Ultraviolet Rays ; Oxidative Stress/radiation effects* ; Keratinocytes/metabolism* ; Molecular Docking Simulation ; Benzofurans/pharmacology* ; Skin Aging/radiation effects* ; Reactive Oxygen Species/metabolism* ; Cell Survival/radiation effects* ; HaCaT Cells ; Hydroxyproline/metabolism* ; Glutathione Peroxidase/metabolism* ; Catalase/metabolism* ; Depsides

Objective:To explore the correlation between ferroptosis-related proteins SLC7A11, GPX4, ACSL4 and the radiosensitivity and prognosis of nasopharyngeal carcinoma. And to investigate the potential of these proteins as molecular markers for predicting the radiosensitivity of nasopharyngeal carcinoma. Methods: A retrospective analysis was conducted on 52 cases of nasopharyngeal carcinoma （nasopharyngeal carcinoma group） and 20 cases of chronic nasopharyngiti s（control group）. The relevant clinical data were reviewed, and paraffin-embedded tissue blocks were collected for study. The expressions of SLC7A11, GPX4, and ACSL4 in pathological specimens were detected by immunohistochemical staining. The expression differences of ferroptosis-related proteins between the nasopharyngeal carcinoma group and the control group were analyzed. The nasopharyngeal carcinoma group was further divided based on the protein expression levels into high and low expression subgroups for SLC7A11, GPX4, and ACSL4. Subsequently, a differential analysis of clinical data and survival analysis was conducted for each of these subgroups. Finally, logistic regression analysis was performed to identify the factors influencing radiotherapy resistance in nasopharyngeal carcinoma. Results:①The differential analysis revealed that, compared to the control group, the nasopharyngeal carcinoma group exhibited significantly higher expression of SLC7A11 and GPX4, and lower expression of ACSL4 （P<0.05）. ②Notably, the proportion of patients displaying radioresistance was higher in the SLC7A11 and GPX4 high expression groups compared to their respective low expression groups （P<0.05）. However, the proportion of radioresistance in the ACSL4 high expression group was lower than that in the ACSL4 low expression group （P<0.05）. Survival analysis indicated that the 5-year overall survival rate was lower in the SLC7A11 and GPX4 high expression groups compared to their respective low expression groups（P<0.05）. However, the 5-year overall survival rate of the ACSL4 high expression group was higher than that of the ACSL4 low expression group（P<0.05）. ③logistic regression analysis showed that SLC7A11 and GPX4 was an independent risk factor for radioresistance in patients with nasopharyngeal carcinoma（P<0.05）. Conclusion:Nasopharyngeal carcinoma tissues over-express SLC7A11, GPX4, and under-express ACSL4. Over-expression of SLC7A11 and GPX4 are independent risk factors for radioresistance in patients with nasopharyngeal carcinoma. The inhibition of ferroptosis may be related to the occurrence, progression and radioresistance of nasopharyngeal carcinoma. Detection of the expression of SLC7A11, GPX4, and ACSL4 has guiding significance for the evaluation of radiosensitivity and prognosis of patients with nasopharyngeal carcinoma.
Humans ; Nasopharyngeal Carcinoma/radiotherapy* ; Nasopharyngeal Neoplasms/pathology* ; Coenzyme A Ligases/metabolism* ; Radiation Tolerance ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Amino Acid Transport System y+/metabolism* ; Prognosis ; Long-Chain-Fatty-Acid-CoA Ligase ; Retrospective Studies ; Ferroptosis ; Male ; Female ; Middle Aged

OBJECTIVES: To investigate the protective effect of catalpol against triptolide-induced liver injury and explore its mechanism to test the Fuzheng Zhidu theory for detoxification. METHODS: C57BL/6J mice were randomized into blank control group, catalpol group, triptolide group and triptolide+catalpol group. After 13 days of treatment with the agents by gavage, the mice were examined for liver tissue pathology, liver function, hepatocyte subcellular structure, lipid peroxidation, ferrous ion deposition and expressions of ferroptosis-related proteins in the liver. In a liver cell line HL7702, the effect of catalpol or the ferroptosis inhibitor Fer-1 on triptolide-induced cytotoxicity was tested by examining cell functions, Fe²⁺ concentration, lipid peroxidation, ROS level and the ferroptosis-related proteins. RESULTS: In C57BL/6J mice, catalpol significantly alleviated triptolide-induced hepatic injury, lowered the levels of ALT, AST and LDH, and reversed the elevation of Fe²⁺ concentration and MDA level and the reduction of GP_X level. In HL7702 cells, inhibition of ferroptosis by Fer-1 significantly reversed triptolide-induced elevation of ALT, AST and LDH levels. Western blotting and qRT-PCR demonstrated that catalpol reversed abnormalities in expressions of SLC7A11, FTH1 and GPX4 at both the mRNA and protein levels in triptolide-treated HL7702 cells. CONCLUSIONS The combined use of catalpol can reduce the hepatotoxicity of triptolide in mice by inhibiting excessive hepatocyte ferroptosis through the SLC7A11/GPX4 pathway.
Animals ; Phenanthrenes/toxicity* ; Ferroptosis/drug effects* ; Diterpenes/toxicity* ; Epoxy Compounds/toxicity* ; Mice, Inbred C57BL ; Hepatocytes/metabolism* ; Mice ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Iridoid Glucosides/pharmacology* ; Liver/metabolism* ; Chemical and Drug Induced Liver Injury/prevention & control* ; Male ; Amino Acid Transport System y+/metabolism*

OBJECTIVES: To explore the mechanism of Shuangshu Decoction (SSD) for inhibiting growth of gastric cancer xenografts in nude mice. METHODS: Network pharmacology analysis was conducted to identify the common targets of SSD and gastric cancer cell ferroptosis, and bioinformatics analysis and molecular docking were used to validate the core targets. In the cell experiment, AGS cells were treated with SSD-medicated serum, Fer-1 (a ferroptosis inhibitor), or both, and the changes in cell viability, ferroptosis markers (ROS, Fe²⁺ and GSH), expressions of P53, SLC7A11 and GPX4, and mitochondrial morphology were examined. In a nude mouse model bearing gastric cancer xenografts, the effects of gavage with SSD, intraperitoneal injection of Fer-1, or their combination on tumor volume/weight, histopathology, and expressions of P53, SLC7A11 and GPX4 levels were evaluated. RESULTS: The active components in SSD (quercetin and wogonin) showed strong binding affinities to P53. In AGS cells, SSD treatment dose-dependently inhibited cell proliferation, increased ROS and Fe²⁺ levels, upregulated P53 expression, and downregulated the expressions of SLC7A11 and GPX4, but these effects were effectively attenuated by Fer-1 treatment. SSD also induced mitochondrial shrinkage and increased the membrane density, which were alleviated by Fer-1. In the tumor-bearing mouse models, gavage with SSD significantly reduced tumor size and weight, caused tumor cell necrosis, upregulated P53 and downregulated SLC7A11 and GPX4 expression in the tumor tissue, and these effects were obviously mitigated by Fer-1 treatment. CONCLUSIONS SSD inhibits gastric cancer growth in nude mice by inducing cell ferroptosis via the P53/SLC7A11/GPX4 axis.
Ferroptosis/drug effects* ; Animals ; Stomach Neoplasms/metabolism* ; Tumor Suppressor Protein p53/metabolism* ; Mice, Nude ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Drugs, Chinese Herbal/pharmacology* ; Humans ; Amino Acid Transport System y+/metabolism* ; Mice ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Xenograft Model Antitumor Assays