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 clinical significance of SLC1A5 overexpression in pan-cancer and its mechanism for promoting hepatocellular carcinoma (HCC) progression. METHODS: We analyzed the correlation of SLC1A5 expression with clinical stage, lymph node metastasis and prognosis in pan-cancer using TCGA and ICGC datasets and explored its association with immune cell infiltration using EPIC, CIBERSORT, and TIMER algorithms. In HCC cell lines, the effects of lentivirus-mediated SLC1A5 overexpression or RNA interference on cell proliferation were examined using CCK-8 assay, and the growth of HCC cell xenografts overexpressing SLC1A5 was observed in nude mice. The effects of SLC1A5 overexpression or silencing in HCC cells on macrophage polarization were evaluated in a cell co-culture system. RESULTS: SLC1A5 was mainly localized on cell membrane and was highly expressed in most cancers in association with clinical stage, lymph node metastasis and poor prognosis. SLC1A5 expression was positively correlated with immunity score in 13 cancer types, especially in low-grade glioma (LGG), LIHC and thyroid cancer. SLC1A5 was positively correlated with macrophage infiltration level in LGG and LIHC but negatively correlated with macrophage infiltration in 5 cancers including lung squamous carcinoma, pancreatic carcinoma, and gastric carcinoma. Patients with SLC1A5 overexpression and high level of M2 macrophage infiltration had the worst survival outcomes. SLC1A5 was correlated with immunosuppression-related genes, cytokines, and cytokine receptors, which was the most obvious in LGG and LIHC. SLC1A5 was highly expressed in different HCC cell lines, and its overexpression promoted HCC cell proliferation both in vitro and in nude mice. In the cell co-culture experiment, SLC1A5 was positively correlated with the molecular markers of M2 polarization of macrophages, and its overexpression strongly promoted M2 polarization of the macrophages and inhibited T cell secretion of IFN-γ. CONCLUSIONS SLC1A5 expression level is correlated with clinical stage, lymph node metastasis, prognosis, and immune cell infiltration in most cancers, and its overexpression promotes HCC progression by inhibiting T-cell function via promoting M2 polarization of macrophages.
Humans ; Carcinoma, Hepatocellular/metabolism* ; Liver Neoplasms/metabolism* ; Animals ; Macrophages/cytology* ; Disease Progression ; Cell Line, Tumor ; Mice ; Amino Acid Transport System ASC/genetics* ; Cell Proliferation ; Lymphatic Metastasis ; Mice, Nude ; Prognosis ; Minor Histocompatibility Antigens

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 investigate the impact of prenatal fear stress on placental amino acid transport and emotion and cognition development in offspring rats. METHODS: Thirty pregnant Wistar rats were randomized equally into control and fear stress (induced using an observational foot shock model) groups. In each group, placental and serum samples were collected from 6 dams on gestational day 20, and the remaining rats delivered naturally and the offspring rats were raised under the same conditions until 8 weeks of age. Emotional and cognitive outcomes of the offspring rats were assessed with behavioral tests, and placental structure was examined using HE staining. Bioinformatics analysis was used to identify differentially expressed placental transporter genes under fear stress. The expressions of system A and system L amino acid transporters, along with other specialized transporters, were detected using qRT-PCR and Western blotting. Fetal serum amino acid concentrations were determined by HPLC. The correlations between fetal amino acid levels and behavioral outcomes of the offspring rats were analyzed. RESULTS: The dams with fear stress showed reduced open-field activity and increased freezing behavior with significantly decreased placental weight, fetal weight, and fetal-to-placental ratio. Bioinformatics analysis revealed 28 differentially expressed transporter genes involved mainly in amino acid transport. In the fear stress group, fetal serum amino acid levels were significantly lowered and Slc38a1, Slc43a1, Slc43a2, Slc7a8, Slc6a6, Slc1a1 and Slc6a9 mRNA and protein expressions were all downregulated. The offspring rats in fear stress group exhibited decreased novel object preference and spontaneous alternation with reduced open arm exploration and increased immobility in emotional tests. Lower early-life amino acid levels was found to correlate with impaired adult cognition. CONCLUSIONS Prenatal fear stress in rats impairs placental amino acid transporter expression and reduces fetal serum amino acid levels, potentially contributing to long-term cognitive deficits in the offspring rats.
Animals ; Female ; Pregnancy ; Placenta/metabolism* ; Fear ; Rats ; Rats, Wistar ; Cognition ; Prenatal Exposure Delayed Effects ; Stress, Psychological ; Amino Acids/blood* ; Amino Acid Transport Systems/metabolism*

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*

Growth arrest DNA damage-inducible protein 45 β (GADD45B) has been reported to be a regulatory factor for active DNA demethylation and is implicated in the modulation of synaptic plasticity and chronic stress-related psychopathological processes. However, its precise role and mechanism of action in stress susceptibility remain elusive. In this study, we found a significant reduction in GADD45B expression specifically in the ventral, but not the dorsal hippocampal CA1 (dCA1) of stress-susceptible mice. Furthermore, we demonstrated that GADD45B negatively regulates susceptibility to social stress and NMDA receptor-dependent long-term potentiation (LTP) in the ventral hippocampal CA1 (vCA1). Importantly, through pharmacological inhibition using the NMDA receptor antagonist MK801, we provided further evidence supporting the hypothesis that GADD45B potentially modulates susceptibility to social stress by influencing NMDA receptor-mediated LTP. Collectively, these results suggested that modulation of NMDA receptor-mediated synaptic plasticity is a pivotal mechanism underlying the regulation of susceptibility to social stress by GADD45B.
Animals ; Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors* ; CA1 Region, Hippocampal/drug effects* ; Male ; Stress, Psychological/physiopathology* ; Mice ; Neuronal Plasticity/drug effects* ; Long-Term Potentiation/drug effects* ; Mice, Inbred C57BL ; Antigens, Differentiation/metabolism* ; Dizocilpine Maleate/pharmacology* ; Excitatory Amino Acid Antagonists/pharmacology* ; GADD45 Proteins

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

Flavonoid 3-O-glucosyltransferase (3GT) is a key enzyme in the glucosidation of anthocyanins. To investigate the 3GT gene in rhododendron, we cloned an open reading frame (ORF) of 3GT gene (named Rh3GT) from Rhododendron hybridum Hort (Red cultivar) and then characterized this gene and the deduced protein in terms of the biochemical characteristics, expression level, and enzymatic function. The results showed that Rh3GT had a full length of 993 bp and encoded 330 amino acid residues. The deduced protein was hydrophilic, stable, weak acid, belonging to the glycosyltransferase family (GT-B type), with glutamine (Q) at position 44 in the PSPG box. The phylogenetic analysis showed that Rh3GT was most closely related to Vc3GT from Vaccinium corymbosum and Vm3GT from Vaccinium myrtillus. Rh3GT was expressed in the stems, leaves, and flowers and almost not expressed in the roots, with the highest expression level in petals during full blooming stage. Introduction of pCAMBIAL1302-Rh3GT into petals significantly up-regulated the expression level of Rh3GT and increased the total anthocyanin accumulation. Rh3GT was successfully expressed in Escherichia coli BL21 in the form of inclusion bodies with a size of about 36 kDa. The results of HPLC showed that the recombinant Rh3GT after denaturation, purification, and dilution could catalyze the synthesis of cyanidin and UDP-glucose to synthesize cyanidin 3-O-glucoside, indicating that the expressed protein had 3GT activity. This study provides basic data for further studying the molecular regulation mechanism of anthocyanin biosynthesis and theoretical support for molecular breeding of rhododendron.
Rhododendron/classification* ; Glucosyltransferases/metabolism* ; Cloning, Molecular ; Escherichia coli/metabolism* ; Recombinant Proteins/biosynthesis* ; Anthocyanins/biosynthesis* ; Phylogeny ; Plant Proteins/metabolism* ; Amino Acid Sequence

Collagen, a vital matrix protein for various tissue and functions in animals, is widely applied in biomaterials. In type Ⅰ collagen, missense mutations of glycine (Gly) in the Gly-Xaa-Yaa triplet of the triple helix are a major cause of osteogenesis imperfecta (OI). Clinical manifestations exhibit marked heterogeneity, spanning a broad disease spectrum from mild skeletal fragility (Type Ⅰ) to severe limb deformities (Type Ⅲ) and perinatal lethal forms (Type Ⅱ). This study utilized recombinant collagen as a model to further elucidate whether Gly→Ala/Val mutations at the N-terminus of the integrin-binding sequence GFPGER affect collagen structure and function, and to explore the underlying mechanisms by which missense mutations impact the biological function of collagen. By introducing Ala and Val substitutions at seven Gly positions N-terminal to the GFPGER sequence, we systematically assessed the effects of these amino acid replacements on the triple-helical structure, thermal stability, integrin-binding ability, and cell adhesion of recombinant collagen. All constructs formed a stable triple-helix structure, with slightly compromised thermal stability. Gly→Val substitutions increased the susceptibility of recombinant collagen to trypsin, which suggested local conformational perturbations in the triple helix. In addition, Gly→Val substitutions significantly reduced the integrin-binding affinity and decreased HT1080 cell adhesion, with the effects stronger than Gly→Ala substitutions. Compared with Gly→Ala substitutions, substitution of Gly with the larger residue Val had enhanced negative effects on the structure and function of recombinant collagen. These findings provide new insights into the molecular mechanisms of osteogenesis imperfecta and offer theoretical references and experimental foundations for the design of collagen sequences and the development of collagen-based biomaterials.
Recombinant Proteins/biosynthesis* ; Glycine/genetics* ; Humans ; Osteogenesis Imperfecta/genetics* ; Integrins/metabolism* ; Collagen/metabolism* ; Collagen Type I/metabolism* ; Amino Acid Substitution ; Mutation ; Mutation, Missense