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*

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

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

OBJECTIVE: To explore the effect of bear bile powder (BBP) on acute lung injury (ALI) and the underlying mechanism. METHODS: The chemical constituents of BBP were analyzed by ultra-high-pressure liquid chromatography-mass spectrometry (UPLC-MS). After 7 days of adaptive feeding, 50 mice were randomly divided into 5 groups by a random number table (n=10): normal control (NC), lipopolysaccharide (LPS), dexamethasone (Dex), low-, and high-dose BBP groups. The dosing cycle was 9 days. On the 12th and 14th days, 20 µL of Staphylococcus aureus solution (bacterial concentration of 1 × 10^-7 CFU/mL) was given by nasal drip after 1 h of intragastric administration, and the mice in the NC group was given the same dose of phosphated buffered saline (PBS) solution. On the 16th day, after 1 h intragastric administration, 100 µL of LPS solution (1 mg/mL) was given by tracheal intubation, and the same dose of PBS solution was given to the NC group. Lung tissue was obtained to measure the myeloperoxidase (MPO) activity, the lung wet/dry weight ratio and expressions of CD14 and other related proteins. The lower lobe of the right lung was obtained for pathological examination. The concentrations of inflammatory cytokines including interleukin (IL)-6, tumour necrosis factor α (TNF-α ) and IL-1β in the bronchoalveolar lavage fluid (BALF) were detected by enzyme linked immunosorbent assay, and the number of neutrophils was counted. The colonic contents of the mice were analyzed by 16 sRNA technique and the contents of short-chain fatty acids (SCFAs) were measured by gas chromatograph-mass spectrometer (GC-MS). RESULTS: UPLC-MS revealed that the chemical components of BBP samples were mainly tauroursodeoxycholic acid and taurochenodeoxycholic acid sodium salt. BBP reduced the activity of MPO, concentrations of inflammatory cytokines, and inhibited the expression of CD14 protein, thus suppressing the activation of NF-κB pathway (P<0.05). The lung histopathological results indicated that BBP significantly reduced the degree of neutrophil infiltration, cell shedding, necrosis, and alveolar cavity depression. Moreover, BBP effectively regulated the composition of the intestinal microflora and increased the production of SCFAs, which contributed to its treatment effect (P<0.05). CONCLUSIONS BBP alleviates lung injury in ALI mouse through inhibiting activation of NF-κB pathway and decreasing expression of CD14 protein. BBP may promote recovery of ALI by improving the structure of intestinal flora and enhancing metabolic function of intestinal flora.
Animals ; Acute Lung Injury/pathology* ; Lipopolysaccharides ; Ursidae ; Gastrointestinal Microbiome/drug effects* ; Bile/chemistry* ; Lipopolysaccharide Receptors/metabolism* ; Powders ; Male ; Lung/drug effects* ; Mice ; Peroxidase/metabolism* ; Signal Transduction/drug effects* ; Cytokines/metabolism*

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

OBJECTIVES: To explore the mechanism of Gandou Fumu Decoction (GDFMD) for improving Wilson's disease (WD) in tx-J mice. METHODS: With 6 syngeneic wild-type mice as the control group, 30 tx-J mice were randomized into WD model group, low-, medium- and high-dose GDFMD treatment groups, and Fer-1 treatment group. Saline (in control and model groups) and GDFMD (3.48, 6.96 or 13.92 g/kg) were administered by gavage, and Fer-1 was injected intraperitoneally once daily for 14 days. Oil red and HE staining were used to observe lipid deposition and pathological conditions in the liver tissue; ALT, AST, albumin, AKP levels were determined to assess liver function of the mice. Western blotting and RT-qPCR were used to detect hepatic protein and mRNA expressions of GPX4, ACSL4, ALOX15, FTH1, FLT, TFR1, FAS, SCD1, and ACOX1, and Fe²⁺, MDA, ROS, SOD, GSH and 4-HNE levels were analyzed to assess oxidative stress. RESULTS: The mouse models of WD showed obvious fatty degeneration in the liver tissue significantly increased serum levels of ALT, AST and AKP, decreased albumin level, increased Fe²⁺, MDA, ROS, 4-HNE levels, decreased SOD and GSH levels (P<0.05), lowered protein expressions of ACOX1, GPX4, FTH1, FLT, FAS, and SCD1, and increased protein contents of TFR1, ACSL4 and ALOX15 in the liver. Treatment with GDFMD and Fer-1 improved liver histopathology and liver function of the mouse models, decreased the levels of Fe²⁺, MDA and ROS, increased SOD and GSH levels, and reversed the changes in hepatic protein expressions. CONCLUSIONS GDFMD improves liver steatosis in mouse models of WD possibly by inhibiting hepatocyte ferroptosis through the GPX4/ACSL4/ALOX15 signaling pathway.
Animals ; Ferroptosis/drug effects* ; Mice ; Signal Transduction/drug effects* ; Drugs, Chinese Herbal/therapeutic use* ; Hepatolenticular Degeneration/drug therapy* ; Hepatocytes/metabolism* ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Fatty Liver/metabolism* ; Arachidonate 15-Lipoxygenase/metabolism* ; Coenzyme A Ligases/metabolism* ; Liver/metabolism* ; Male

OBJECTIVES: To evaluate the therapeutic effect of gastrodin against hypoxic-ischemic brain damage (HIBD) in neonatal mice and explore the role of GPX4/SLC7A11/FTH1 signaling in mediating its effect. METHODS: Twenty-four 9- to 11-day-old C57BL/6J mice were randomized equally into 4 groups for sham operation, HIBD modeling by right common carotid artery ligation and subsequent exposure to hypoxia for 1 h, or gastrodin treatment at 100 or 200 mg/kg before and at 1 and 2 days after modeling. The mice then underwent neurological assessment (Zea-Longa scores), and the cerebral cortical penumbra tissue were collected for HE and Nissl staining, detection of ferroptosis biomarkers and protein expressions of GPX4, SLC7A11, and FTH1 with Western blotting and immunofluorescence co-localization, and observation of mitochondrial ultrastructure with electron microscopy. In cultured HT22 neuronal cells with oxygen-glucose deprivation (OGD) for 2 h, the effects of pretreatments with 0.5 mmol/L gastrodin, 10 μmol/L RSL3 (a GPX4 inhibitor), alone or in combination, were analyzed on expressions of ferroptosis-related proteins, cellular Fe²⁺, ROS, lipid peroxidation, MDA, and GSH levels, mitochondrial membrane potential (JC-1), and cell viability. RESULTS: Gastrodin treatment at the two doses both significantly ameliorated HIBD and neurological deficits of the mice, reduced mitochondrial damage and Fe²⁺, MDA and ROS levels, increased GSH level, and upregulated GPX4, SLC7A11, and FTH1 protein expressions. In HT22 cells, gastrodin pretreatment obviously attenuated OGD-induced ferroptosis and improved cell viability and mitochondrial function. Co-treatment with RSL3 potently abrogated the inhibitory effects of gastrodin on Fe²⁺, ROS, BODIPY-C11, and MDA levels and attenuated its protective effects on GSH level, cell viability, and mitochondrial membrane potential. CONCLUSIONS Gastrodin provides neuroprotective effects in neonatal mice with HIBD by suppressing neuronal ferroptosis via upregulating the GPX4/SLC7A11/FTH1 signaling pathway.
Animals ; Ferroptosis/drug effects* ; Hypoxia-Ischemia, Brain/drug therapy* ; Mice ; Mice, Inbred C57BL ; Signal Transduction/drug effects* ; Phospholipid Hydroperoxide Glutathione Peroxidase ; Glucosides/pharmacology* ; Animals, Newborn ; Benzyl Alcohols/pharmacology* ; Amino Acid Transport System y+/metabolism*