Expression Of SLC7A11 Research Articles

Citrus rhoifolin alleviated DSS-induced acute colitis by activating CEMIP/SLC7A11-mediated cystine uptake and inhibiting epithelial ferroptosis.

Pharmacological inhibition of ferroptosis, a specific form of regulated cell death, has emerged as a promising therapeutic strategy for alleviating symptoms and enhancing endoscopic outcomes in patients suffering from ulcerative colitis. Rhoifolin, a prominent bioactive constituent abundant in the widely consumed fruit Citrus grandis (grapefruit), has garnered attention for its ability to diminish the levels of reactive oxygen species (ROS), which are key inducers of ferroptosis across diverse cellular contexts. In this study, we aimed to investigate whether rhoifolin exerts its beneficial effects on colitis by modulating the process of epithelial ferroptosis. Colitis model was successfully established in C57BL/6 mice through the administration of 2.5% dextran sulfate sodium (DSS) solution for a duration of 9days, which was freely accessible for drinking. RNA sequencing was conducted to delve into the mechanisms underlying the rhoifolin-mediated effects on colitis. To evaluate the impact of rhoifolin on ferroptosis in epithelial cells, several key indicators were measured, including mitochondrial morphology, colonic glutathione (GSH) levels, lipid peroxidation product contents, and ROS levels. The results indicated that rhoifolin exhibited profound anti-colitis properties and effectively curbs ferroptosis in epithelial cells of mice subjected to DSS treatment. The RNA sequencing analysis further revealed that rhoifolin stimulated a remarkable upregulation of colonic cell migration-inducing protein (CEMIP) expression by approximately 2.4-fold in colitis-affected mice. Notably, depletion of CEMIP significantly blocked the rhoifolin-induced increase in the cystine transporter solute carrier family 7 member 11 (SLC7A11, from 1.9-fold to approximately 1.1-fold), as well as the elevation of cystine uptake (from 1.72-fold to 1.2-fold) and glutathione (GSH) biosynthesis (from 2.1-fold to 1.2-fold), and the suppression of epithelial ferroptosis (from 0.51-fold to 0.94-fold) in mice with colitis. Molecular docking investigations have pinpointed crucial amino acid residues within CEMIP, specifically His267, His289, and Phe265, as the primary interaction sites (docking score: -7.8kcal/mol), facilitating the engagement of rhoifolin via hydrogen bonding interactions. Rhoifolin significantly mitigated DSS-induced colitis primarily through inhibiting epithelial ferroptosis. The activation of CEMIP by citrus-derived rhoifolin led to a notable upregulation of SLC7A11 expression, thereby enhanced cystine uptake and facilitated GSH biosynthesis, ultimately suppressed the occurrence of ferroptosis in epithelial cells.

Angiotensin II Induces Vascular Endothelial Dysfunction by Promoting Lipid Peroxidation-Mediated Ferroptosis via CD36

Angiotensin II (Ang II) is an effective vasoconstriction peptide, a major effector molecule of the renin–angiotensin–aldosterone system (RAAS) and one of the important causes of endothelial dysfunction. Ferroptosis is considered to be involved in the occurrence and development of cardiovascular diseases. This study is dedicated to exploring the role and mechanism of Ang II-induced ferroptosis in HUVECs and to finding molecular targets for vascular endothelial injury and dysfunction during the progression of hypertension. In this study, we found that with the increase in exposure concentration, the intracellular ROS content and apoptosis rate increased significantly, the NO release decreased significantly in the medium- and high-concentration groups and the ET-1 content in the high-concentration group increased significantly. The expression of ZO-1 protein was significantly decreased in the high-concentration group. The expression of p-eNOS, VE-cadherin and Occludin protein showed a dose-dependent downward trend, while the ICAM-1 protein showed an upward trend. Ang II caused lipid metabolism disorders in HUVECs, and the PL–PUFAs associated with ferroptosis were significantly increased. In addition, Ang II promoted a significant increase in intracellular free Fe2+ content and MDA and a significant decrease in GSH content. Furthermore, the expression of GPX4, SLC7A11 and SLC3A2 was down-regulated, the expression of ACSL4, LPCAT3 and ALOX15 was up-regulated, and the ratio of p-cPLA2/cPLA2 was increased. After the intervention of ferroptosis inhibitor Fer-1, the injury and dysfunction of HUVECs induced by Ang II were significantly rescued. Immunofluorescence results showed that the expression of CD36 showed a significant increasing trend and was localized in the cytoplasm. Over-expression of CD36 promoted Ang II-induced ferroptosis and endothelial dysfunction. In conclusion, Ang II induces the injury of HUVECs, decreases vascular diastole and endothelial barrier-related molecules, and increases vascular constriction and adhesion-related molecules, which may be related to CD36 and its mediated lipid peroxidation and ferroptosis signals.

The LINC01094/miR-545-3p/SLC7A11 Signaling Axis Promotes the Development of Gastric Cancer by Regulating Cell Growth and Ferroptosis.

This study aimed to investigate the role and mechanism of action of LINC01094 in the development of gastric cancer (GC). The expression levels of LINC01094 in GC patients and healthy individuals were analyzed online using the Cancer Genome Atlas database. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot analyses were performed to determine the expression of LINC01094/miR-545-3p/SLC7A11 in GC tissues and cells. Functional experiments (MTT assay, colony formation assay, and flow cytometry) were conducted to assess the effect of LINC01094 and miR-545-3p on cell proliferation, viability, apoptosis, cell cycle, and reactive oxygen species. Correlations between LINC01094 and miR-545-3p, as well as SLC7A11, were analyzed and validated using the dual-luciferase reporter assay and RNA immunoprecipitation. The levels of Fe2+, malondialdehyde, and glutathione in the cells were measured biochemically, and the protein expression levels of Bcl-2, cleaved caspase3, Cyclin D1, and p21 were detected by Western blotting. LINC01094 was significantly upregulated in the GC tissues and cells with a targeting relationship with miR-545-3p; the expression levels of LINC01094 and miR-545-3p were negatively correlated. Knockdown of LINC01094 notably inhibited the proliferation and viability of GC cells and promoted cell ferroptosis, which, however, was abrogated by the silencing of miR-545-3p. These findings indicate that miR-545-3p could target and positively correlate with SLC7A11 expression. Additionally, LINC01094 could promote GC cell progression and affect cellular ferroptosis by regulating the miR-545-3p/SLC7A11 signaling axis.

FXR deficiency induced ferroptosis via modulation of the CBP-dependent p53 acetylation to suppress breast cancer growth and metastasis.

Farnesoid X receptor (NR1H4/FXR) functions as a scavenger of lipid peroxide products and drives the proliferation and metastasis of various cancers. However, the underlying molecular mechanisms remain poorly understood. In our study, we found that the expression levels of FXR, vimentin and SLC7A11 were significantly higher in breast cancer tissues, particularly in metastatic cancer tissues compared to non-metastatic ones. Furthermore, the increased FXR expression was positively correlated with vimentin and SLC7A11 in clinical tumor specimens. In addition, a high level of FXR correlated with poor prognosis in patients with breast cancer. Both Z-Guggulsterone (Z-GS), as a pharmacological inhibitor of FXR, and silencing FXR curbed proliferation and migration of breast cancer cells by promoting ferroptosis. Notably, our results showed that FXR competitively bound to CREB-binding protein (CBP) to suppress the interaction between p53 and CBP in the nucleus, and thus prevented p53 acetylation at lys382, which was essential for upregulating the expression of SLC7A11. Conversely, FXR knockdown increased the interaction between p53 and CBP and promoted p53 acetylation, which ultimately led to facilitating ferroptosis in breast cancer cells. More importantly, we also found that Z-GS inhibited TGF-β1-induced tumor growth and metastasis of breast cancer primarily through ferroptosis via regulating CBP-dependent p53 acetylation in nude mice. In conclusion, the FXR was first reported as a tumor promoter that enhanced the proliferation and metastasis of breast cancer cells through regulating CBP-dependent p53 K382 acetylation. It proposes that FXR may serve as a potential therapeutic target for the treatment of breast cancer.

Pharmacological activation of aldehyde dehydrogenase 2 inhibits ferroptosis via SLC7A11/GPX4 axis to reduce kidney stone formation.

Calcium oxalate (CaOx) kidney stones pose a global health challenge due to their high prevalence and recurrence rates. While cell death mechanisms such as ferroptosis are known to play a crucial role in stone formation, the precise underlying mechanisms remain enigmatic. Aldehyde dehydrogenase 2 (ALDH2) is a metabolic enzyme of the ferroptosis product 4-hydroxy-2-nonenal (4-HNE). However, the function of ALDH2 in kidney stones is poorly understood. In this study, we observed a downregulation of aldehyde dehydrogenase 2 (ALDH2) in the stone group. Significantly, the administration of Alda-1, an ALDH2 agonist, notably reduced crystal deposition in the kidneys and hindered crystal adhesion to cells. Furthermore, Alda-1 induced upregulation of SLC7A11 expression, promoting glutathione synthesis, reducing lipid peroxidation accumulation, and lowering Fe2+ levels. These collective effects attenuated crystal-induced ferroptosis. However, the renoprotective effects of Alda-1 were inhibited by SLC7A11 siRNA. In conclusion, our study explores the applications of Alda-1 and highlights the potential of targeting ALDH2 as a promising therapeutical strategy for urolithiasis.

TRIM46 accelerates H1N1 influenza virus-induced ferroptosis and inflammatory response by regulating SLC7A11 ubiquitination.

Influenza A (H1N1) virus is an acute respiratory infection responsible for enormous morbidity and mortality worldwide. The tripartite motif-containing protein 46 (TRIM46) has an antiviral function that inhibits various viral infections. This study is designed to explore the role and mechanism of TRIM46 in the progress of H1N1 infection. Herein, we infected A549 or 16HBE cells with the H1N1 virus at different times to assess TRIM46 and solute carrier family 7 member 11 (SLC7A11) expression. TRIM46 and Influenza A nucleoprotein mRNA levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). TRIM46, solute carrier family 7 member 11 (SLC7A11), and Nucleoprotein protein levels were detected using protein level were detected by western blot assay. Cell virulence was determined using Virulence assay (TCID50) assay. Cell viability was determined using Cell Counting Kit-8 (CCK-8) assay. Reactive oxygen species (ROS), intracellular iron content, Malondialdehyde (MDA), and Glutathione (GSH) levels were determined using special assay kits. The stability of SLC7A11 was assessed by Cycloheximide (CHX) assay. Interaction between TRIM46 and SLC7A11 was verified using Co-immunoprecipitation (CoIP) assay. The biological role of TRIM46 was assessed in H1N1 virus-challenged lung injury mice in vivo. TRIM46 level was significantly increased during H1N1 virus infection, and SLC7A11 expression was decreased. TRIM46 downregulation could suppress H1N1 virus replication and relieve H1N1 infection-induced ferroptosis and inflammation in A549 or 16HBE cells. Mechanistically, TRIM46 could promote SLC7A11 ubiquitination and decrease its stability. TRIM46 knockdown repressed H1N1 virus-induced lung injury in vivo. TRIM46 could contribute to influenza A H1N1 virus infection by promoting SLC7A11 ubiquitination in A549 cells, which indicates that targeting TRIM46 may improve the prognosis of patients.

Calycosin alleviates ferroptosis and attenuates doxorubicin-induced myocardial injury via the Nrf2/SLC7A11/GPX4 signaling pathway

BackgroundHeart failure is primarily characterized by damage to the structure and function of the heart. Ferroptosis represents a form of programmed cell death, and studies indicate that it constitutes one of the primary mechanisms underlying cardiomyocyte death in heart failure. Calycosin, a natural compound derived from astragalus, exhibits various pharmacological properties, including anti-ferroptosis, antioxidant effects, and cardiovascular protection. Nonetheless, the specific role of Calycosin in the treatment of ferroptosis in heart failure remains poorly understood.ObjectiveThis study aims to elucidate the regulatory effect of Calycosin on ferroptosis and its influence on the treatment mechanisms of heart failure through in vivo and in vitro experiments.MethodsA rat model of heart failure was induced using doxorubicin, and the cardiac function was evaluated through cardiac ultrasound examination and NT-Pro BNP detection. Myocardial injury was assessed using H&E staining and Masson staining. The extent of mitochondrial damage was evaluated through transmission electron microscopy. Concurrently, the level of ferroptosis was analyzed by measuring ferroptosis markers, including MDA, ferrous ions, the GSH/GSSG ratio, and GPX4 activity. Subsequently, the molecular mechanism by which Calycosin exerts its therapeutic effects in heart failure was investigated through immunofluorescence and Western blotting. Finally, H9c2 cardiomyocytes were treated with doxorubicin to simulate myocardial injury, and the mechanism by which Calycosin mediates its effects in the treatment of heart failure was further verified through Nrf2 gene silencing.ResultsCalycosin significantly improves cardiac function in rats, reduces serum NT-Pro BNP levels, and alleviates myocardial cell damage. Additionally, it significantly decreases the levels of ferroptosis in myocardial tissue, as confirmed through transmission electron microscopy and the assessment of ferroptosis markers, including MDA, ferrous ions, GSH, and GPX4 activity. At the molecular level, Calycosin exerts its effects by activating the Nrf2/SLC7A11/GPX4 signaling pathway, evidenced by the upregulation of Nrf2, SLC7A11, GPX4, GSS, and GCL protein expression. This process substantially enhances the antioxidant capacity of rat myocardial tissue and effectively suppresses ferroptosis in myocardial cells. The results obtained from both in vivo and in vitro experiments are consistent. Notably, when Nrf2 is silenced, the protective effect of Calycosin on the myocardium is markedly diminished.ConclusionCalycosin effectively treats doxorubicin-induced cardiac injury, and its therapeutic effect is likely closely associated with the activation of the Nrf2/SLC7A11/GPX4 signaling pathway and the inhibition of ferroptosis in myocardial cells. Consequently, Calycosin, as a promising compound against doxorubicin-induced cardiotoxicity, warrants further investigation.

Targeting Disulfidptosis with Potentially Bioactive Natural Products in Metabolic Cancer Therapy

Background: Metabolic cancers are defined by metabolic reprogramming. Although this reprograming drives rapid tumour growth and invasion, it also reveals specific metabolic vulnerabilities that can be therapeutically exploited in cancer therapy. A novel form of programmed cell death, known as disulfidptosis, was identified last year; tumour cells with high SLC7A11 expression undergo disulfidptosis when deprived of glucose. Natural products have attracted increasing attention and have shown potential to treat metabolic cancers through diverse mechanisms. Methods: We systematically searched electronic databases involving PubMed, Web of Science, Gooale Scholar. To ensue comprehensive exploration, keywords including metabolic reprogramming, metabolic cancer, disulfidptosis, natural products and some other words were employed. Results: In this review, we focus on the shared characteristics and metabolic vulnerabilities of metabolic cancers. Additionally, we discuss the molecular mechanisms underlying disulfidptosis and highlight key regulatory genes. Furthermore, we predict bioactive natural products that target disulfidptosis-related genes, offering new perspectives for anticancer strategies through the modulation of disulfidptosis. Conclusions: By summarizing current research progress, this review mainly analyzed the potential mechanisms of natural products in the treatment of metabolic cancer.

Lycium barbarum polysaccharide alleviates ferroptosis in Sertoli cells through NRF2/SLC7A11/GPX4 pathway and ameliorates DEHP-induced male reproductive damage in mice

Di-(2-ethylhexyl)phthalate (DEHP) is a common plasticizer that has been shown to significantly negatively affect male reproductive health. On the other hand, Lycium barbarum polysaccharide (LBP) has been shown to improve reproductive function. Therefore, we hypothesized that LBP may ameliorate DEHP-induced male reproductive damage. Herein, we found that LBP could alleviate DEHP-induced testicular damage and sperm abnormalities. Furthermore, histomorphological analysis of mice testis revealed that LBP primarily ameliorated the DEHP-induced male reproductive damage by targeting Sertoli cells. Moreover, the detection of the function-related genes of Sertoli cells confirmed this finding. The serum of mice in the Control, DEHP, and DEHP+LBP groups was analyzed using non-targeted metabolomics to further elucidate the mechanism of action of LBP in improving DEHP-induced male reproductive damage. According to the results, the differential metabolites were mainly enriched in the glutamate metabolism pathway, implying that LBP may alleviate the ferroptosis-related DEHP-induced testicular injury. Related ferroptosis markers were also found in mice testis. These findings collectively suggest that LBP may ameliorate DEHP-induced testicular injury via alleviating ferroptosis in Sertoli cells. To clarify the specific mechanism, we constructed a cell model in vitro by treating TM4 cells (the Sertoli cell line) with LBP and MEHP (the in vivo DEHP metabolite). Our findings revealed that LBP can improve the function of DEHP-affected Sertoli cells. Furthermore, the analysis of lipid peroxidation, Fe2+ content, and ferroptosis-related protein expressions demonstrated that LBP could ameliorate MEHP-induced ferroptosis in TM4 cells. To clarify the specific mechanism, glutamate metabolism-related proteins involved in the ferroptosis pathway were detected. According to the results, there were significant changes in the expression of NRF2, SLC7A11 and GPX4 proteins, which are involved in the ferroptosis glutamate metabolism pathway. Furthermore, supplementation of NRF2, SLC7A11, and GPX4 inhibitors (ML385, Erastin, and RSL3, respectively) blocked the therapeutic effect of LBP in alleviating MEHP-induced ferroptosis in TM4 cells, implying that LBP could also ameliorate MEHP-induced ferroptosis via the NRF2/SLC7A11/GPX4 pathway. In summary, these findings show that LBP can alleviate DEHP/MEHP-induced ferroptosis through the NRF2/SLC7A11/GPX4 pathway, ameliorating Sertoli cell dysfunction and improving the DEHP-induced male reproductive damage. Therefore, the clinical administration of LBP could be an effective strategy for preventing DEHP-induced male reproductive injury.

Reactivation of MAPK-SOX2 pathway confers ferroptosis sensitivity in KRASG12C inhibitor resistant tumors

The clinical success of KRASG12C inhibitors (G12Ci) including AMG510 and MRTX849 is limited by the eventual development of acquired resistance. A novel and effective treatment to revert or target this resistance is urgent. To this end, we established G12Ci (AMG510 and MRTX849) resistant KRASG12C mutant cancer cell lines and screened with an FDA-approved drug library. We found the ferroptosis inducers including sorafenib and lapatinib stood out with an obvious growth inhibition in the G12Ci resistant cells. Mechanistically, the G12Ci resistant cells exhibited reactivation of MAPK signaling, which repressed SOX2-mediated expression of cystine transporter SLC7A11 and iron exporter SLC40A1. Consequently, the low intracellular GSH level but high iron content engendered hypersensitivity of these resistant tumors to ferroptosis inducers. Ectopic overexpression of SOX2 or SLC7A11 and SLC40A1 conferred resistance to ferroptosis in the G12Ci resistant cells. Ferroptosis induced by sulfasalazine (SAS) achieved obvious inhibition on the tumor growth of xenografts derived from AMG510-resistant KRASG12C-mutant cells. Collectively, our results suggest a novel therapeutic strategy to treat patients bearing G12Ci resistant cancers with ferroptosis inducers.

OTUB1 regulation of ferroptosis and the protective role of ferrostatin-1 in lupus nephritis

Lupus nephritis (LN) is a prevalent and severe manifestation of systemic lupus erythematosus (SLE), leading to significant morbidity and mortality. OTUB1, a deubiquitinating enzyme, has emerged as a potential therapeutic target due to its role in cellular protection and regulation of ferroptosis, a form of cell death linked to LN. Our study revealed significantly reduced OTUB1 expression in the glomeruli of LN patients and podocytes, correlated with disease severity. CRISPR/Cas9-mediated OTUB1 knockout in podocytes resulted in pronounced injury, indicated by decreased levels of nephrin and podocin. Ferrostatin-1 treatment effectively mitigated this injury, restoring SLC7A11 expression and significantly reducing MDA levels, Fe2+ levels, BODIPY C11 expression, and normalized cysteine and glutathione expression. In the MRL/lpr mouse model, Ferrostatin-1 significantly improved renal function decreased proteinuria, and ameliorated renal histopathological changes, including reduced glomerular endothelial swelling, mesangial cell proliferation, and leukocyte infiltration. These results underscore the protective role of Ferrostatin-1 in modulating the pathogenesis of LN. OTUB1 plays a crucial protective role against podocyte injury in LN by regulating ferroptosis. Ferrostatin-1 effectively mitigates podocyte damage induced by OTUB1 deficiency, suggesting that targeting ferroptosis could be a promising therapeutic strategy for LN.

The High Expression of SLC7A11 and GPX4 are Significantly Correlated with β-Catenin in Colorectal Cancer

The High Expression of SLC7A11 and GPX4 are Significantly Correlated with β-Catenin in Colorectal Cancer

Enhancer of Zeste Homolog 2 Protects Mucosal Melanoma from Ferroptosis via the KLF14-SLC7A11 Signaling Pathway.

Mucosal melanoma (MM) is epidemiologically, biologically, and molecularly distinct from cutaneous melanoma. Current treatment strategies have failed to significantly improve the prognosis for MM patients. This study aims to identify therapeutic targets and develop combination strategies by investigating the mechanisms underlying the tumorigenesis and progression of MM. We analyzed the copy number amplification of enhancer of zeste homolog 2 (EZH2) in 547 melanoma patients and investigated its correlation with clinical prognosis. Utilizing cell lines, organoids, and patient-derived xenograft models, we assessed the impact of EZH2 on cell proliferation and sensitivity to ferroptosis. Further, we explored the mechanisms of ferroptosis resistance associated with EZH2 by conducting RNA sequencing and chromatin immunoprecipitation sequencing. EZH2 copy number amplification was closely associated with malignant phenotype and poor prognosis in MM patients. EZH2 was essential for MM cell proliferation in vitro and in vivo. Moreover, genetic perturbation of EZH2 rendered MM cells sensitized to ferroptosis. Combination treatment of EZH2 inhibitor with ferroptosis inducer significantly inhibited the growth of MM. Mechanistically, EZH2 inhibited the expression of Krüpple-Like factor 14 (KLF14), which binds to the promoter of solute carrier family 7 member 11 (SLC7A11) to repress its transcription. Loss of EZH2 therefore reduced the expression of SLC7A11, leading to reduced intracellular SLC7A11-dependent glutathione synthesis to promote ferroptosis. Our findings not only establish EZH2 as a biomarker for MM prognosis but also highlight the EZH2-KLF14-SLC7A11 axis as a potential target for MM treatment.

Puerarin Ameliorates Ferroptosis in Neuronal Injury Through the PI3K/AKT Signaling Pathway

Ferroptosis plays an important role in the pathogenesis of neuronal damage, generally mediated by iron and lipid peroxidation. In the present study, we measured the protective effects of puerarin against corticosterone-induced neuronal injury via PI3K/AKT-mediated activation of nuclear factor erythroid 2-related factor 2 (Nrf2). After exposing corticosterone-treated PC12 cells to indicated compounds, we measured the key regulators of ferroptosis (ferritin, SLC7A11, and Ptgs2), ferroptosis events (levels of iron, ROS, MDA, and GSH), and the PI3K/AKT/Nrf2 axis. Corticosterone induced ferroptosis in PC12 cells, evidenced by reduced levels of ferritin, SLC7A11, and GSH and increased levels of iron, ROS, and MDA. These effects were reversed by inhibiting ferroptosis with ferrostatin-1. Puerarin-mediated activation of Nrf2 repressed ferroptosis in corticosterone-treated PC12 cells by upregulating ferritin and SLC7A11 expression. Moreover, the protective effects of puerarin on ferroptosis in corticosterone-treated cells relied on the activation of the PI3K/AKT pathway though the upregulation of nuclear Nrf2. These findings indicate that ferroptosis plays an essential role in corticosterone-induced neuronal damage, and puerarin protects against ferroptosis in corticosterone-treated cells via PI3K/AKT-mediated activation of Nrf2.

Unraveling the Ferroptosis-inducing Potential of Methanol Leaves Extract of Prosopis Juliflora Via Downregulation of SLC7A11 and GPX4 mRNA Expression in A549 Lung Cancer Cells.

Prosopis juliflora has been employed in many traditional treatments. As evidenced by our earlier research, Prosopis juliflora leaf methanol extract (PJME) has a promising future in the fight against lung cancer. It may also be used in conjunction with other treatments to effectively manage lung cancer. The main objective of this study was to explore the potential of PJME to inhibit lung cancer in A549 cells, along with its underlying mechanisms of action. The antiproliferative effects were determined using MTT and LDH tests. Apoptosis- inducing capacity was evaluated using the DAPI staining, caspase-3 test, cytochrome C assay, PARP cleavage, and qRT-PCR. To investigate the mechanism of action of PJME in lung cancer, the levels of ROS, MMP, GSH, MDA, and specific ferroptosis indicators were measured. The experimental data of the current study indicated that exposure of A549 cells to PJME reduced cell viability and increased cellular cytotoxicity. The apoptosis-inducing ability of PJME in A549 cells was validated by enhanced nuclear condensation, level of the caspase- 3, cytochrome C, and PARP release. In addition, qRT-PCR investigations verified that the administration of PJME led to a decrease in the expression of anti-apoptotic gene Bcl2 while enhancing the mRNA level of pro-apoptotic genes, such as Bax and caspase-3, in A549 cells. The study also found that PJME has the ability to activate ferroptosis pathways, as evidenced by elevated reactive oxygen species (ROS) generation, changes in the levels of antioxidant markers (MDA and GSH), and decreased expression of SLC7A11 and GPX4. The results of the present study clearly showed that PJME inhibited the proliferation of A549 cells and induced ferroptosis by reducing the expression of the important targets SLC7A11 and GPX4. Further research is necessary to fully understand the clinical efficacy of PJME before it can be investigated as supplemental or adjuvant therapy for lung cancer.

Disulfidptosis-related subtype and prognostic signature in prostate cancer

BackgroundDisulfidptosis refers to cell death caused by the accumulation and bonding of disulfide in the cytoskeleton protein of SLC7A11-high level cells under glucose deprivation. However, the role of disulfidptosis-related genes (DRGs) in prostate cancer (PCa) classification and regulation of the tumor microenvironment remains unclear.MethodsFirstly, we analyzed the expression and mutation landscape of DRGs in PCa. We observed the expression levels of SLC7A11 in PCa cells through in vitro experiments and assessed the inhibitory effect of the glucose transporter inhibitor BAY-876 on SLC7A11-high cells using CCK-8 assay. Subsequently, we performed unsupervised clustering of the PCa population and analyzed the differentially expressed genes (DEGs) between clusters. Using machine learning techniques to select a minimal gene set and developed disulfidoptosis-related risk signatures for PCa. We analyzed the tumor immune microenvironment and the sensitivity to immunotherapy in different risk groups. Finally, we validated the accuracy of the prognostic signatures genes using single-cell sequencing, qPCR, and western blot.ResultsAlthough SLC7A11 can increase the migration ability of tumor cells, BAY-876 effectively suppressed the viability of prostate cancer cells, particularly those with high SLC7A11 expression. Based on the DRGs, PCa patients were categorized into two clusters (A and B). The risk label, consisting of a minimal gene set derived from DEGs, included four genes. The expression levels of these genes in PCa were initially validated through in vitro experiments, and the accuracy of the risk label was confirmed in an external dataset. Cluster-B exhibited higher expression levels of DRG, representing lower risk, better prognosis, higher immune cell infiltration, and greater sensitivity to immune checkpoint blockade, whereas Cluster A showed the opposite results. These findings suggest that DRGs may serve as targets for PCa classification and treatment. Additionally, we constructed a nomogram that incorporates DRGs and clinical pathological features, providing clinicians with a quantitative method to assess the prognosis of PCa patients.ConclusionThis study analyzed the potential connection between disulfidptosis and PCa, and established a prognostic model related to disulfidptosis, which holds promise as a valuable tool for the management and treatment of PCa patients.

Dexmedetomidine preconditioning attenuates ferroptosis in myocardial ischemia-reperfusion injury via α2 adrenergic receptor activation

ObjectiveDexmedetomidine (Dex) is a potent agonist of the α2 adrenergic receptor that has been shown to possess sedative and hypnotic properties. Dex can protect against myocardial ischemia-reperfusion injury (MIRI) by inhibiting ferroptosis. However, these studies were based on Dex post-conditioning, and the role of α2 adrenergic receptors in this process is unclear. In this study, we investigated whether Dex preconditioning can prevent MIRI by attenuating ferroptosis and whether this effect depends on α2 adrenergic receptors in rats. MethodsMale Sprague–Dawley rats were randomly assigned to five groups: sham (saline-treated), I/R (ischemia-exposed), Dex + I/R (Dex pre-treatment), Dex + Yoh + I/R (Dex and yohimbine pre-treatment), and Yoh + I/R (yohimbine pre-treatment). Cardiac function, myocardial infarction, and morphological changes were assessed. Transmission electron microscopy was used to analyze mitochondrial morphology. Ferroptosis-related indicators and lipid peroxidation were measured using western blotting and qRT-PCR. ResultsOur findings indicated that Dex preconditioning improved cardiac function, reduced infarct size and apoptosis, and inhibited ferroptosis in the rat myocardium after MIRI. These effects were associated with the upregulation of Nrf2, SLC7A11, and GPX4 expression, as well as the downregulation of Ferritin, TFR1, ACSL4, COX2, IL-1β, IL-6, and TNF-α expression. Importantly, yohimbine, an α2 adrenergic receptor antagonist, abolished these protective effects. ConclusionThese results suggest that Dex preconditioning can prevent MIRI by attenuating ferroptosis via α2 adrenergic receptor activation and by modulating the Nrf2/SLC7A11/GPX4 pathway.

ACSS2 regulates ferroptosis in an E2F1-dependent manner in breast cancer brain metastatic cells.

Brain metastasis diagnosis in breast cancer patients is considered an end-stage event. The median survival after diagnosis is measured in months, thus there is an urgent need to develop novel treatment strategies. Breast cancers that metastasize to the brain must adapt to the unique brain environment and are highly dependent on acetate metabolism for growth and survival. However, the signaling pathways that regulate survival in breast cancer brain metastatic (BCBM) tumors are not known. Primary brain tumor cells can convert acetate to acetyl-CoA via phosphorylation of acetyl-CoA synthetase 2 (ACSS2) by the cyclin-dependent kinase-5 (CDK5) regulated by the nutrient sensor O-GlcNAc transferase (OGT). Here, we show that breast cancer cells selected to metastasize to the brain contain increased levels of O-GlcNAc, OGT and ACSS2-Ser267 phosphorylation compared to parental breast cancer cells. Moreover, OGT and CDK5 are required for breast cancer cell growth in the brain parenchyma in vivo. Importantly, ACSS2 and ACSS2-S267D phospho-mimetic mutant are critical for in vivo breast cancer growth in the brain but not in the mammary fat pad. Mechanistically, we show that ACSS2 regulates BCBM cell survival by suppressing ferroptosis via regulation of E2F1-mediated expression of anti-ferroptotic proteins SLC7A11 and GPX4. Lastly, we show treatment with a novel brain-permeable small molecule ACSS2 inhibitor induced ferroptosis and reduced BCBM growth ex vivo and in vivo. These results suggest a crucial role for ACSS2 in protecting from ferroptosis in breast cancer brain metastatic cells and suggests that breast cancer brain metastatic cells may be susceptible to ferroptotic inducers.

α4 Nicotinic Acetylcholine Receptors in Lipopolysaccharide-Related Lung Inflammation

Sepsis remains an important healthcare challenge. The lungs are often affected in sepsis, resulting in acute lung injury characterized by inflammation. Mechanisms involving lipopolysaccharide (LPS) stimulation of toll-like receptor (TLR) signaling with induction of proinflammatory pathways have been implicated in this process. To date, however, studies targeting these pathways have failed to improve outcomes. We have found that LPS may also promote lung injury through the activation of α4 nicotinic acetylcholine receptors (α4 nAChRs) in immune cells. We observed increased expression of α4 nAChRs in human THP-1 monocytic cells exposed to LPS (100 ng/mL, 24 h). We also observed that LPS stimulated the expression of other relevant genes, including tumor necrosis factor-α, interleukin-1β, plasminogen activator inhibitor-1, the solute carrier family 7 member 11, extracellular superoxide dismutase, and transforming growth factor-β1. Of interest, dihydro-β-erythroidine hydrobromide (DHβE), a specific chemical inhibitor of α4 nAChRs, inhibited the LPS-induced expression of these genes. We generated mice with a global knockout mutation of the α4 nAChR subunit in the C57BL/6 background using CRISPR/Cas9 technology. The lungs of these LPS-treated animals demonstrated a reduction in the expression of the above-mentioned genes when compared with the lungs of wild-type animals. In support of the role of oxidative stress, we observed that LPS induced expression of the cystine transporter Slc7a11 in both THP-1 cells and in wild-type mouse lungs. The effects of LPS on THP-1 cells were blocked by the thiol antioxidant N-acetylcysteine and mimicked by redox stress. Importantly, the induction of IL-1β by redox stress was inhibited by the α4 nAChR inhibitor DHβE. Finally, we showed that LPS stimulated calcium influx in THP-1 cells, which was blocked by the α4 nAChR inhibitor. Our observations suggest that LPS promotes lung injury by stimulating redox stress, which activates α4 nAChR signaling and drives proinflammatory cytokine expression.

HMGA2 regulates GPX4 expression and ferroptosis in prostate cancer cells

Prostate cancer (PCa) remains a significant global health burden and an increase in oxidative stress is associated with cancer progression. High Mobility Group A2 (HMGA2), a chromatin architectural protein, increases oxidative stress and promotes sensitivity to ferroptosis inducers, however, the mechanism is unknown. We investigated the role of HMGA2 in GPX4 regulation and the impact on cellular responses to oxidative stress and ferroptosis sensitivity. We conducted UALCAN database analysis, western blot analysis, and lipid peroxidation assays to determine the relationship between HMGA2 and GPX4 and the levels of lipid reactive oxygen species in a panel of PCa cell lines, including an enzalutamide-resistant cancer cell line (C4–2B MDVR). Our results show an inverse relationship between HMGA2 and GPX4 expression with high HMGA2 and low GPX4 expression associated with higher Gleason score and lower survival probability in prostate adenocarcinoma (PRAD) patients, while low/moderate HMGA2 expression is positively associated with increased GPX4 expression and higher survival probability. Cell lines showed a moderately negative but not statistically significant correlation between HMGA2 and GPX4 expression, however, PC3 and DU145 PCa cells display higher lipid peroxides concomitant with higher endogenous levels of HMGA2 and low GPX4. Overexpression of wild-type HMGA2 in LNCaP and 22Rv1 cells leads to higher HMGA2 expression compared to Neo control and is associated with higher SLC7A11 and GPX4 expression, while interestingly truncated HMGA2 overexpression in LNCaP and 22Rv1 cells coincides with higher HMGA2 and reduced GPX4 expression, leading to increased lipid peroxides and susceptibility to ferroptosis. Overexpression of wild-type and truncated HMGA2 in 22Rv1 cells increases SLC7A11 mRNA yet differing GPX4 protein expression suggests posttranslational regulation of GPX4. Moreover, enzalutamide-resistant C4–2B MDVR cells display higher HMGA2 levels compared to C4–2B cells, as well as sensitivity to RSL3 ferroptosis inducer, which is partially reversed by ferroptosis inhibitor, ferrostatin-1. Interestingly, GPX4 expression is higher in C4–2B MDVR cells compared to C4–2B, and HMGA2 knockdown further increases its expression but does not significantly alter its susceptibility to ferroptosis. In conclusion, our study shows that HMGA2 regulation of GPX4 expression is complex and truncated HMGA2 downregulates GPX4 and increases lipid peroxides. Moreover, HMGA2-expressing cells including enzalutamide-resistant cells are susceptible to RSL-3-induced ferroptosis. Thus, ferroptosis sensitivity offers promising insights for the development of targeted therapeutic interventions for aggressive PCa.