ALOX5-mediated ferroptosis acts as a distinct cell death pathway upon oxidative stress in Huntington's disease

Haloacetamides disinfection by-products, a potential risk factor for nonalcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a metabolic disorder characterized by abnormal lipid deposition, with oxidative stress being a risk factor in its onset and progression. Haloacetamides (HAcAms), as unregulated disinfection by-products in drinking water, may alter the incidence and severity of NAFLD through the production of oxidative stress. We explored whether HAcAms at 1, 10, and 100-fold concentrations in Shanghai drinking water perturbed lipid metabolism in normal human liver LO-2 cells. CRISPR/Cas9 was used to construct a LO-2 line with stable NRF2 knock-down (NRF2-KD) to investigate the mechanism underlying abnormal lipid accumulation and hepatocyte damage caused by mixed exposure to HAcAms. At 100-fold real-world concentration, HAcAms caused lipid deposition and increased triglyceride accumulation in LO-2 cells, consistent with altered de novo lipogenesis. Differences in responses to HAcAms in normal and NRF2-KD LO-2 cells indicated that HAcAms caused hepatocyte lipid deposition and triglyceride accumulation by activation of the NRF2/PPARγ pathway and aggravated liver cell toxicity by inducing ferroptosis. These results indicate that HAcAms are important risk factors for NAFLD. Further observations and verifications of the effect of HAcAms on NAFLD in the population are warranted in the future.

Lipid Quality Control and Ferroptosis: From Concept to Mechanism

Cellular quality control systems sense and mediate homeostatic responses to prevent the buildup of aberrant macromolecules, which arise from errors during biosynthesis, damage by environmental insults, or imbalances in enzymatic and metabolic activity. Lipids are structurally diverse macromolecules that have many important cellular functions, ranging from structural roles in membranes to functions as signaling and energy-storage molecules. As with other macromolecules, lipids can be damaged (e.g., oxidized), and cells require quality control systems to ensure that nonfunctional and potentially toxic lipids do not accumulate. Ferroptosis is a form of cell death that results from the failure of lipid quality control and the consequent accumulation of oxidatively damaged phospholipids. In this review, we describe a framework for lipid quality control, using ferroptosis as an illustrative example to highlight concepts related to lipid damage, membrane remodeling, and suppression or detoxification of lipid damage via preemptive and damage-repair lipid quality control pathways.

Quercetin Alleviates LPS-Stimulated Myocardial Injury through Regulating ALOX5/PI3K/AKT Pathway in Sepsis

Quercetin (QUE) has been found to inhibit the progression of sepsis-related diseases, including sepsis-induced cardiomyopathy (SIC). More information about the role and mechanism of QUE in SIC progression deserves further exploration. Human cardiomyocytes (AC16) were induced with LPS to mimic SIC cell models. Cell proliferation and apoptosis were determined using CCK8 assay, EdU assay, and flow cytometry. Cell inflammation and ferroptosis were evaluated by detecting IL-1β, TNF-α, Fe2+, ROS, GSH, and GPX4 levels. 5-lipoxygenase (ALOX5) expression was examined by quantitative real-time PCR and western blot. LPS treatment reduced AC16 cell proliferation, while enhanced apoptosis, inflammation, and ferroptosis. QUE repressed LPS-induced AC16 cell apoptosis, inflammation, and ferroptosis. ALOX5 was upregulated in SIC patients, and its expression was reduced by QUE. ALOX5 knockdown restrained LPS-induced apoptosis, inflammation, and ferroptosis in AC16 cells. The inhibitory effect of QUE on LPS-induced myocardial injury could be reversed by ALOX5 overexpression. QUE promoted the activity of PI3K/AKT pathway by reducing ALOX5 expression. QUE could alleviate LPS-induced myocardial injury by regulating ALOX5/PI3K/AKT pathway, suggesting that QUE might be used for treating SIC.

CRISPR/Cas9-mediated neuronal deletion of 5-lipoxygenase alleviates deficits in mouse models of epilepsy

INTRODUCTION

Our previous work reveals a critical role of activation of neuronal Alox5 in exacerbating brain injury post seizures. However, whether neuronal Alox5 impacts the pathological process of epilepsy remains unknown.

OBJECTIVES

To prove the feasibility of neuron-specific deletion of Alox5 via CRISPR-Cas9 in the blockade of seizure onset and epileptic progression.

METHODS

Here, we employed a Clustered regularly interspaced short-palindromic repeat-associated proteins 9 system (CRISPR/Cas9) system delivered by adeno-associated virus (AAV) to specifically delete neuronal Alox5 gene in the hippocampus to explore its therapeutic potential in various epilepsy mouse models and possible mechanisms.

RESULTS

Neuronal depletion of Alox5 was successfully achieved in the brain. AAV delivery of single guide RNA of Alox5 in hippocampus resulted in reducing seizure severity, delaying epileptic progression and improving epilepsy-associated neuropsychiatric comorbidities especially anxiety, cognitive deficit and autistic-like behaviors in pilocarpine- and kainic acid-induced temporal lobe epilepsy (TLE) models. In addition, neuronal Alox5 deletion also reversed neuron loss, neurodegeneration, astrogliosis and mossy fiber sprouting in TLE model. Moreover, a battery of tests including analysis of routine blood test, hepatic function, renal function, routine urine test and inflammatory factors demonstrated no noticeable toxic effect, suggesting that Alox5 deletion possesses the satisfactory biosafety. Mechanistically, the anti-epileptic effect of Alox5 deletion might be associated with reduction of glutamate level to restore excitatory/inhibitory balance by reducing CAMKII-mediated phosphorylation of Syn ISer603.

CONCLUSION

Our findings showed the translational potential of AAV-mediated delivery of CRISPR-Cas9 system including neuronal Alox5 gene for an alternative promising therapeutic approach to treat epilepsy.

Oxidative Metabolism as a Cause of Lipid Peroxidation in the Execution of Ferroptosis

Ferroptosis is a type of nonapoptotic cell death that is characteristically caused by phospholipid peroxidation promoted by radical reactions involving iron. Researchers have identified many of the protein factors that are encoded by genes that promote ferroptosis. Glutathione peroxidase 4 (GPX4) is a key enzyme that protects phospholipids from peroxidation and suppresses ferroptosis in a glutathione-dependent manner. Thus, the dysregulation of genes involved in cysteine and/or glutathione metabolism is closely associated with ferroptosis. From the perspective of cell dynamics, actively proliferating cells are more prone to ferroptosis than quiescent cells, which suggests that radical species generated during oxygen-involved metabolism are responsible for lipid peroxidation. Herein, we discuss the initial events involved in ferroptosis that dominantly occur in the process of energy metabolism, in association with cysteine deficiency. Accordingly, dysregulation of the tricarboxylic acid cycle coupled with the respiratory chain in mitochondria are the main subjects here, and this suggests that mitochondria are the likely source of both radical electrons and free iron. Since not only carbohydrates, but also amino acids, especially glutamate, are major substrates for central metabolism, dealing with nitrogen derived from amino groups also contributes to lipid peroxidation and is a subject of this discussion.

The molecular mechanism of ferroptosis and its relationship with Parkinson's disease

Neurodegenerative diseases such as Parkinson's disease (PD) have complex pathogenetic mechanisms. Genetic, age, and environmental factors are all related to PD. Due to the unclear pathogenesis of PD and the lack of effective cure methods, it is urgent to find new targets for treating PD patients. Ferroptosis is a form of cell death that is reliant on iron and exhibits distinct morphological and mechanistic characteristics compared to other types of cell death. It encompasses a range of biological processes, including iron/lipid metabolism and oxidative stress. In recent years, research has found that ferroptosis plays a crucial role in the pathophysiological processes of neurodegenerative diseases and stroke. Therefore, ferroptosis is also closely related to PD, This article reviews the core mechanisms of ferroptosis and elucidates the correlation between PD and ferroptosis. In addition, new compounds that have emerged in recent years to exert anti PD effects by inhibiting the ferroptosis signaling pathway were summarized. I hope to further elaborate the relationship between ferroptosis and PD through the review of this article, and provide new strategies for developing PD treatments targeting ferroptosis.

Puerarin modulates proliferation, inflammation and ECM metabolism in human nucleus pulposus mesenchymal stem cells via the lncRNA LINC01535

Background

Intervertebral disc degeneration (IVDD) is a highly prevalent musculoskeletal disorder characterized by progressive destruction of the intervertebral disc, leading to chronic low back pain and disability. Emerging evidence suggests that dysregulation of ferroptosis, a recently discovered form of regulated cell death, participates in IVDD pathogenesis. Puerarin, a natural flavonoid compound from Pueraria lobata, has shown promise in modulating ferroptosis in various diseases.

Methods

Human nucleus pulposus-derived mesenchymal stem cells (NPMSCs) were isolated and identified by flow cytometry. We investigated the effects of puerarin on human NPMSCs and examined the underlying molecular mechanisms.

Results

Puerarin significantly promoted human NPMSC proliferation, as evidenced by the increased cell viability and colony formation ability. Furthermore, puerarin suppressed the expression of cyclooxygenase-2 and the proinflammatory cytokine interleukin-6 in NPMSCs, demonstrating the anti-inflammatory properties of the compound. Notably, puerarin attenuated ECM breakdown by downregulating the ECM-degrading enzymes MMP3, MMP13 and ADAMTS5, and it increased ECM component synthesis, including collagen type II and aggrecan, by NPMSCs. Moreover, puerarin inhibited ferroptosis in NPMSCs by modulating the expression of key ferroptosis-related genes, including ACSL4, PTGS2 and GPX4. Depletion of LINC01535 abolished the effects of puerarin on proliferation, inflammation and ECM metabolism, suggesting a key role of this lncRNA in mediating the effects of puerarin.

Conclusion

Our findings show that puerarin promotes the proliferation of human NPMSCs and ECM synthesis by these cells. Furthermore, puerarin inhibits inflammation and ECM degradation by suppressing ferroptosis via LINC01535. These results provide insights into the molecular mechanisms underlying the therapeutic effects of puerarin in IVDD. Targeting ferroptosis and its regulatory factors, such as LINC01535, may have therapeutic potential for the treatment of IDD and other degenerative disorders of the intervertebral disc. Further studies are needed to uncover the translational potential of puerarin and its downstream targets in preclinical and clinical applications.

Ferroptosis: a novel mechanism of cell death in ophthalmic conditions

Ferroptosis, a new type of programmed cell death proposed in recent years, is characterized mainly by reactive oxygen species and iron-mediated lipid peroxidation and differs from programmed cell death, such as apoptosis, necrosis, and autophagy. Ferroptosis is associated with a variety of physiological and pathophysiological processes. Recent studies have shown that ferroptosis can aggravate or reduce the occurrence and development of diseases by targeting metabolic pathways and signaling pathways in tumors, ischemic organ damage, and other degenerative diseases related to lipid peroxidation. Increasing evidence suggests that ferroptosis is closely linked to the onset and progression of various ophthalmic conditions, including corneal injury, glaucoma, age-related macular degeneration, diabetic retinopathy, retinal detachment, and retinoblastoma. Our review of the current research on ferroptosis in ophthalmic diseases reveals significant advancements in our understanding of the pathogenesis, aetiology, and treatment of these conditions.

Uncovering the ferroptosis related mechanism of laduviglusib in the cell-type-specific targets of the striatum in Huntington's disease

Huntington's disease (HD) is a dominantly inherited neurodegenerative disorder featured by abnormal movements, arising from the extensive neuronal loss and glial dysfunction in the striatum. Although the causes and pathogenetic mechanisms of HD are well established, the development of disease-modifying pharmacological therapies for HD remains a formidable challenge. Laduviglusib has demonstrated neuroprotective effects through the enhancement of mitochondrial function in the striatum of HD animal models. Ferroptosis is a nonapoptotic form of cell death that occurs as a consequence of lethal iron-dependent lipid peroxidation and mitochondrial dysfunction. However, the ferroptosis-related mechanisms underlying the neuroprotective effects of laduviglusib in the striatum of HD patients remain largely uncharted. In this study, we leveraged single-nucleus RNA sequencing data obtained from the striatum of HD patients in stages 2-4 to identify differentially expressed genes within distinct cell-type. We subsequently integrated these differentially expressed genes of HD, laduviglusib target genes and ferroptosis-related genes to predict the ferroptosis-related mechanisms underpinning the neuroprotective effects of laduviglusib in HD patients. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses unveiled that the effects of laduviglusib on direct pathway striatal projection neurons (dSPNs) is mainly associated with Th17 cell differentiation pathways. Conversely, its impact on indirect pathway striatal projection neurons (iSPNs) extends to the Neurotrophin signaling pathway, FoxO signaling pathway, and reactive oxygen species pathway. In microglia, laduviglusib appears to contribute to HD pathology via mechanisms related to Th17 cell differentiation and the FoxO signaling pathway. Further, molecular docking results indicated favorable binding of laduviglusib with PARP1 (associated with dSPNs and iSPNs), SCD (associated with astrocytes), ALOX5 (associated with microglia), and HIF1A (associated with dSPNs, iSPNs, and microglia). In addition, the KEGG results suggest that laduviglusib may enhance mitochondrial function and protect against neuronal loss by targeting ferroptosis-related signaling pathways, particularly mediated by ALOX5 in microglia. These findings provide valuable insights into the potential mechanisms through which laduviglusib exerts its effects on distinct cell-types within the HD striatum.

The research landscape of ferroptosis in neurodegenerative disease: a bibliometric analysis

Background

Ferroptosis, a newly proposed concept of programmed cell death, has garnered significant attention in research across different diseases in the last decade. Despite thorough citation analyses in neuroscience, there is a scarcity of information on ferroptosis research specifically related to neurodegenerative diseases.

Method

The Web of Science Core Collection database retrieved relevant articles and reviews. Data on publications, countries, institutions, authors, journals, citations, and keywords in the included studies were systematically analyzed using Microsoft Excel 2019 and CiteSpace 6.2.R7 software.

Result

A comprehensive analysis and visualization of 563 research papers on ferroptosis in neurodegenerative diseases from 2014 to 2023 revealed emerging research hotspots and trends. The number of annual publications in this field of study has displayed a pattern of stabilization in the early years of the decade, followed by a notable increase in the later years and peaking in 2023 with 196 publications. Regarding publication volume and total citations, notable research contributions were observed from countries, institutions, and authors in North America, Western Europe, and China. Current research endeavors primarily focus on understanding the intervention mechanisms of neurodegenerative diseases through the ferroptosis pathway and exploring and identifying potential therapeutic targets.

Conclusion

The study highlights key areas of interest and emerging trends in ferroptosis research on neurodegenerative diseases, offering valuable insights for further exploration and potential directions for diagnosing and treating such conditions.

E3 ligases and DUBs target ferroptosis: A potential therapeutic strategy for neurodegenerative diseases

Ferroptosis is a form of cell death mediated by iron and lipid peroxidation (LPO). Recent studies have provided compelling evidence to support the involvement of ferroptosis in the pathogenesis of various neurodegenerative diseases (NDDs), such as Alzheimer's disease (AD), Parkinson's disease (PD). Therefore, understanding the mechanisms that regulate ferroptosis in NDDs may improve disease management. Ferroptosis is regulated by multiple mechanisms, and different degradation pathways, including autophagy and the ubiquitinproteasome system (UPS), orchestrate the complex ferroptosis response by directly or indirectly regulating iron accumulation or lipid peroxidation. Ubiquitination plays a crucial role as a protein posttranslational modification in driving ferroptosis. Notably, E3 ubiquitin ligases (E3s) and deubiquitinating enzymes (DUBs) are key enzymes in the ubiquitin system, and their dysregulation is closely linked to the progression of NDDs. A growing body of evidence highlights the role of ubiquitin system enzymes in regulating ferroptosis sensitivity. However, reports on the interaction between ferroptosis and ubiquitin signaling in NDDs are scarce. In this review, we first provide a brief overview of the biological processes and roles of the UPS, summarize the core molecular mechanisms and potential biological functions of ferroptosis, and explore the pathophysiological relevance and therapeutic implications of ferroptosis in NDDs. In addition, reviewing the roles of E3s and DUBs in regulating ferroptosis in NDDs aims to provide new insights and strategies for the treatment of NDDs. These include E3- and DUB-targeted drugs and ferroptosis inhibitors, which can be used to prevent and ameliorate the progression of NDDs.

Oxidative Stress, Lipid Peroxidation and Ferroptosis Are Major Pathophysiological Signatures in the Placental Tissue of Women with Late-Onset Preeclampsia

Preeclampsia, a serious and potentially life-threatening medical complication occurring during pregnancy, is characterized by hypertension and often accompanied by proteinuria and multiorgan dysfunction. It is classified into two subtypes based on the timing of diagnosis: early-onset (EO-PE) and late-onset preeclampsia (LO-PE). Despite being less severe and exhibiting distinct pathophysiological characteristics, LO-PE is more prevalent than EO-PE, although both conditions have a significant impact on placental health. Previous research indicates that different pathophysiological events within the placenta may contribute to the development of preeclampsia across multiple pathways. In our experimental study, we investigated markers of oxidative stress, ferroptosis, and lipid peroxidation pathways in placental tissue samples obtained from women with LO-PE (n = 68) compared to healthy control pregnant women (HC, n = 43). Through a comprehensive analysis, we observed an upregulation of specific molecules associated with these pathways, including NADPH oxidase 1 (NOX-1), NADPH oxidase 2 (NOX-2), transferrin receptor protein 1 (TFRC), arachidonate 5-lipoxygenase (ALOX-5), acyl-CoA synthetase long-chain family member 4 (ACSL-4), glutathione peroxidase 4 (GPX4) and malondialdehyde (MDA) in women with LO-PE. Furthermore, increased ferric tissue deposition (Fe3+) was observed in placenta samples stained with Perls' Prussian blue. The assessment involved gene and protein expression analyses conducted through RT-qPCR experiments and immunohistochemistry assays. Our findings underscore the heightened activation of inflammatory pathways in LO-PE compared to HC, highlighting the pathological mechanisms underlying this pregnancy disorder.

Hederagenin protects against myocardial ischemia-reperfusion injury via attenuating ALOX5-mediated ferroptosis

Hederagenin (HDG), a medical herb, is known for its beneficial activities against diverse diseases. The cardioprotective effect of HDG has been preliminarily disclosed, but the efficacy and underlying mechanism by which HDG protects against myocardial ischemia-reperfusion (MI/R) injury have not been elucidated yet. To simulate MI/R injury, the left anterior descending artery was occluded for 30 min and then reperfusion for 120 min in a rat model, and the cellular model of hypoxia-reoxygenation (H/R) injury was constructed in H9c2 cardiomyocytes. Hematoxylin-eosin, Prussian blue, and 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining were conducted to assess the histological injury, iron deposition, and myocardial infarction. Myocardial enzymes and oxidative stress-related factors were detected using their commercial kits. Lipid peroxidation was measured using BODIPY581/591 probe, and iron content was detected. Cell counting kit (CCK)-8, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), and flow cytometry assays were performed to assess cell viability and apoptosis. Protein levels were investigated by western blot. The interaction between HDG and 5-lipoxygenase (ALOX5) was verified using molecular docking. Our findings indicated that HDG significantly attenuated myocardial dysfunction by reducing infarction and myocardial injury. HDG significantly attenuated myocardial apoptosis in vitro and in vivo, as well as alleviating oxidative stress via reducing reactive oxygen species (ROS) and maintaining the balance between antioxidant and oxidant enzymes. Meanwhile, HDG inhibited I/R-induced ferroptosis in myocardium and cardiomyocytes, including reducing lipid peroxidation and iron level. Moreover, the binding relationship between HDG and ALOX5 was verified, and HDG could concentration dependently downregulate ALOX5. Furthermore, ALOX5 overexpression eliminated the inhibition of HDG on H/R-induced apoptosis, oxidative stress, and ferroptosis in H9c2 cardiomyocytes. HDG ameliorated myocardial dysfunction and cardiomyocyte injury by reducing apoptosis, oxidative stress, and ferroptosis through inhibiting ALOX5, providing a new perspective on the prevention and treatment of MI/R injury.

Inhibition of lysyl oxidase by pharmacological intervention and genetic manipulation alleviates epilepsy-associated cognitive disorder

Epilepsy-associated cognitive disorder (ECD), a prevalent comorbidity in epilepsy patients, has so far uncharacterized etiological origins. Our prior work revealed that lysyl oxidase (Lox) acted as a novel contributor of ferroptosis, a recently discovered cell death mode in the regulation of brain function. However, the role of Lox-mediated ferroptosis in ECD remains unknown. ECD mouse model was established 2 months later following a single injection of kainic acid (KA) for. After chronic treatment with KA, mice were treated with different doses (30 mg/kg, 100 mg/kg and 300 mg/kg) of Lox inhibitor BAPN. Additionally, hippocampal-specific Lox knockout mice was also constructed and employed to validate the role of Lox in ECD. Cognitive functions were assessed using novel object recognition test (NOR) and Morris water maze test (MWM). Protein expression of phosphorylated cAMP-response element binding (CREB), a well-known molecular marker for evaluation of cognitive performance, was also detected by Western blot. The protein distribution of Lox was analyzed by immunofluorescence. In KA-induced ECD mouse model, ferroptosis process was activated according to upregulation of 4-HNE protein and a previously discovered ferroptosis in our group, namely, Lox was remarkably increased. Pharmacological inhibition of Lox by BAPN at the dose of 100 mg/kg significantly increased the discrimination index following NOR test and decreased escape latency as well as augmented passing times within 60 s following MWM test in ECD mouse model. Additionally, deficiency of Lox in hippocampus also led to pronounced improvement of deficits in ECD model. These findings indicate that the ferroptosis regulatory factor, Lox, is activated in ECD. Ablation of Lox by either pharmacological intervention or genetic manipulation ameliorates the impairment in ECD mouse model, which suggest that Lox serves as a promising therapeutic target for treating ECD in clinic.

Identification of Differentially Expressed Genes in Cold Storage-associated Kidney Transplantation

BACKGROUND

Although it is acknowledged that ischemia-reperfusion injury is the primary pathology of cold storage-associated kidney transplantation, its underlying mechanism is not well elucidated.

METHODS

To extend the understanding of molecular events and mine hub genes posttransplantation, we performed bulk RNA sequencing at different time points (24 h, day 7, and day 14) on a murine kidney transplantation model with prolonged cold storage (10 h).

RESULTS

In the present study, we showed that genes related to the regulation of apoptotic process, DNA damage response, cell cycle/proliferation, and inflammatory response were steadily elevated at 24 h and day 7. The upregulated gene profiling delicately transformed to extracellular matrix organization and fibrosis at day 14. It is prominent that metabolism-associated genes persistently took the first place among downregulated genes. The gene ontology terms of particular note to enrich are fatty acid oxidation and mitochondria energy metabolism. Correspondingly, the key enzymes of the above processes were the products of hub genes as recognized. Moreover, we highlighted the proximal tubular cell-specific increased genes at 24 h by combining the data with public RNA-Seq performed on proximal tubules. We also focused on ferroptosis-related genes and fatty acid oxidation genes to show profound gene dysregulation in kidney transplantation.

CONCLUSIONS

The comprehensive characterization of transcriptomic analysis may help provide diagnostic biomarkers and therapeutic targets in kidney transplantation.

Deciphering Ferroptosis: From Molecular Pathways to Machine Learning-Guided Therapeutic Innovation

Ferroptosis is a unique form of cell death reliant on iron and lipid peroxidation. It disrupts redox balance, causing cell death by damaging the plasma membrane, with inducers acting through enzymatic pathways or transport systems. In cancer treatment, suppressing ferroptosis or circumventing it holds significant promise. Beyond cancer, ferroptosis affects aging, organs, metabolism, and nervous system. Understanding ferroptosis mechanisms holds promise for uncovering novel therapeutic strategies across a spectrum of diseases. However, detection and regulation of this regulated cell death are still mired with challenges. The dearth of cell, tissue, or organ-specific biomarkers muted the pharmacological use of ferroptosis. This review covers recent studies on ferroptosis, detailing its properties, key genes, metabolic pathways, and regulatory networks, emphasizing the interaction between cellular signaling and ferroptotic cell death. It also summarizes recent findings on ferroptosis inducers, inhibitors, and regulators, highlighting their potential therapeutic applications across diseases. The review addresses challenges in utilizing ferroptosis therapeutically and explores the use of machine learning to uncover complex patterns in ferroptosis-related data, aiding in the discovery of biomarkers, predictive models, and therapeutic targets. Finally, it discusses emerging research areas and the importance of continued investigation to harness the full therapeutic potential of targeting ferroptosis.

The crystal structure of human ferroptosis suppressive protein 1 in complex with flavin adenine dinucleotide and nicotinamide adenine nucleotide

Ferroptosis is a recently discovered form of regulated cell death characterized by its distinct dependence on iron and the peroxidation of lipids within cellular membranes. Ferroptosis plays a crucial role in physiological and pathological situations and has attracted the attention of numerous scientists. Ferroptosis suppressive protein 1 (FSP1) is one of the main regulators that negatively regulates ferroptosis through the GPX4-independent FSP1-CoQ10-NAD(P)H axis and is a potential therapeutic target for ferroptosis-related diseases. However, the crystal structure of FSP1 has not been resolved, which hinders the development of therapeutic strategies targeting FSP1. To unravel this puzzle, we purified the human FSP1 (hFSP1) protein using the baculovirus eukaryotic cell expression system and solved its crystal structure at a resolution of 1.75 Å. Furthermore, we evaluated the oxidoreductase activity of hFSP1 with NADH as the substrate and identified E156 as the key amino acid in maintaining hFSP1 activity. Interestingly, our results indicated that hFSP1 exists and functions in a monomeric state. Mutagenesis analysis revealed the critical role of the C-terminal domain in the binding of substrate. These findings significantly enhance our understanding of the functional mechanism of FSP1 and provide a precise model for further drug development.

Modulation of ferroptosis by non‑coding RNAs in cancers: Potential biomarkers for cancer diagnose and therapy

Ferroptosis is a recently discovered cell programmed death. Extensive researches have indicated that ferroptosis plays an essential role in tumorigenesis, development, migration and chemotherapy drugs resistance, which makes it become a new target for tumor therapy. Non-coding RNAs (ncRNAs) are considered to control a wide range of cellular processes by modulating gene expression. Recent studies have indicated that ncRNAs regulate the process of ferroptosis via various pathway to affect the development of cancer. However, the regulation network remains ambiguous. In this review, we outlined the major metabolic processes of ferroptosis and concluded the relationship between ferroptosis-related ncRNAs and cancer progression. In addition, the prospect of ncRNAs being new therapeutic targets and early diagnosis biomarkers for cancer by regulating ferroptosis were presented, and the possible obstacles were also predicted. This could help in discovering novel cancer early diagnostic methods and therapeutic approaches.

Ferroptosis: Emerging Role in Diseases and Potential Implication of Bioactive Compounds

Ferroptosis is a form of cell death that is distinguished from other types of death for its peculiar characteristics of death regulated by iron accumulation, increase in ROS, and lipid peroxidation. In the past few years, experimental evidence has correlated ferroptosis with various pathological processes including neurodegenerative and cardiovascular diseases. Ferroptosis also is involved in several types of cancer because it has been shown to induce tumor cell death. In particular, the pharmacological induction of ferroptosis, contributing to the inhibition of the proliferative process, provides new ideas for the pharmacological treatment of cancer. Emerging evidence suggests that certain mechanisms including the Xc- system, GPx4, and iron chelators play a key role in the regulation of ferroptosis and can be used to block the progression of many diseases. This review summarizes current knowledge on the mechanism of ferroptosis and the latest advances in its multiple regulatory pathways, underlining ferroptosis' involvement in the diseases. Finally, we focused on several types of ferroptosis inducers and inhibitors, evaluating their impact on the cell death principal targets to provide new perspectives in the treatment of the diseases and a potential pharmacological development of new clinical therapies.

Effect of ferroptosis on chronic cerebral hypoperfusion in vascular dementia

Vascular dementia (VaD) is the second most prevalent type of dementia after Alzheimer's disease and is caused by impaired nerve cell function resulting from cerebrovascular disease and vascular risk factors. Chronic cerebral hypoperfusion (CCH) is a common pathological and physiological state that may result from cerebral ischemia and hypoxia, causing widespread diffuse lesions in the brain parenchyma which leads to progressive nerve damage. Transferrin (TF) and transferrin receptor 1 (TfR1), two proteins involved in iron uptake, were upregulated by CCH, whereas ferroprotein (FPN), a protein involved in iron efflux, was downregulated. This process may involve various mechanisms including tau and iron regulatory proteins (IRP). CCH can also exacerbate lipid peroxidation caused by an iron imbalance by inhibiting glutathione peroxidase 4 (Gpx4) synthesis and some Gpx4 independent pathways through cystine/glutamate transporters (system Xc-), ultimately leading to ferroptosis in nerve cells and accelerating the progression of VaD.

Lycopene Prevents Phthalate-Induced Cognitive Impairment via Modulating Ferroptosis

Di-(2-ethylhexyl) phthalate (DEHP) is frequently used as a plasticizer in industrial and agricultural products. DEHP can cause severe neurotoxicity, such as impaired learning and memory function. Lycopene (LYC) as a carotenoid exerts excellent antioxidant capacity and therapeutic effects in neurodegenerative diseases. However, whether LYC can prevent the cognitive impairment induced by DEHP and the specific mechanisms are unclear. In the present study, the behavioral test results suggested that LYC alleviated the learning and memory impairment induced by DEHP. The histopathological data revealed that LYC attenuated DEHP-induced disordered arrangement of the neurons in the CA1 and CA3 regions of the hippocampus tissue. Moreover, LYC inhibited the occurrence of DEHP-induced ferroptosis via regulating iron metabolism, inhibiting lipid peroxidation, and activating the cysteine transporter and nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (NrF2/HO-1) signaling pathway. Overall, the study contributes novel perspectives into the potential mechanisms of LYC preventing phthalate-induced cognitive impairment in the hippocampus.

The mechanism of ferroptosis and its related diseases

Ferroptosis, a regulated form of cellular death characterized by the iron-mediated accumulation of lipid peroxides, provides a novel avenue for delving into the intersection of cellular metabolism, oxidative stress, and disease pathology. We have witnessed a mounting fascination with ferroptosis, attributed to its pivotal roles across diverse physiological and pathological conditions including developmental processes, metabolic dynamics, oncogenic pathways, neurodegenerative cascades, and traumatic tissue injuries. By unraveling the intricate underpinnings of the molecular machinery, pivotal contributors, intricate signaling conduits, and regulatory networks governing ferroptosis, researchers aim to bridge the gap between the intricacies of this unique mode of cellular death and its multifaceted implications for health and disease. In light of the rapidly advancing landscape of ferroptosis research, we present a comprehensive review aiming at the extensive implications of ferroptosis in the origins and progress of human diseases. This review concludes with a careful analysis of potential treatment approaches carefully designed to either inhibit or promote ferroptosis. Additionally, we have succinctly summarized the potential therapeutic targets and compounds that hold promise in targeting ferroptosis within various diseases. This pivotal facet underscores the burgeoning possibilities for manipulating ferroptosis as a therapeutic strategy. In summary, this review enriched the insights of both investigators and practitioners, while fostering an elevated comprehension of ferroptosis and its latent translational utilities. By revealing the basic processes and investigating treatment possibilities, this review provides a crucial resource for scientists and medical practitioners, aiding in a deep understanding of ferroptosis and its effects in various disease situations.

Ferroptosis-Regulated Cell Death as a Therapeutic Strategy for Neurodegenerative Diseases: Current Status and Future Prospects

Ferroptosis is increasingly being recognized as a key element in the pathogenesis of diverse diseases. Recent studies have highlighted the intricate links between iron metabolism and neurodegenerative disorders. Emerging evidence suggests that iron homeostasis, oxidative stress, and neuroinflammation all contribute to the regulation of both ferroptosis and neuronal health. However, the precise molecular mechanisms underlying the involvement of ferroptosis in the pathological processes of neurodegeneration and its impact on neuronal dysfunction remain incompletely understood. In our Review, we provide a comprehensive analysis and summary of the potential molecular mechanisms underlying ferroptosis in neurodegenerative diseases, aiming to elucidate the disease progression of neurodegeneration. Additionally, we discuss potential therapeutic agents that modulate ferroptosis with the goal of identifying novel drug molecules for the treatment of neurodegenerative disorders.

Regulation of VKORC1L1 is critical for p53-mediated tumor suppression through vitamin K metabolism

Here, we identified vitamin K epoxide reductase complex subunit 1 like 1 (VKORC1L1) as a potent ferroptosis repressor. VKORC1L1 protects cells from ferroptosis by generating the reduced form of vitamin K, a potent radical-trapping antioxidant, to counteract phospholipid peroxides independent of the canonical GSH/GPX4 mechanism. Notably, we found that VKORC1L1 is also a direct transcriptional target of p53. Activation of p53 induces downregulation of VKORC1L1 expression, thus sensitizing cells to ferroptosis for tumor suppression. Interestingly, a small molecular inhibitor of VKORC1L1, warfarin, is widely prescribed as an FDA-approved anticoagulant drug. Moreover, warfarin represses tumor growth by promoting ferroptosis in both immunodeficient and immunocompetent mouse models. Thus, by downregulating VKORC1L1, p53 executes the tumor suppression function by activating an important ferroptosis pathway involved in vitamin K metabolism. Our study also reveals that warfarin is a potential repurposing drug in cancer therapy, particularly for tumors with high levels of VKORC1L1 expression.

ATP2B3 Inhibition Alleviates Erastin-Induced Ferroptosis in HT-22 Cells through the P62-KEAP1-NRF2-HO-1 Pathway

Ferroptosis participates in the occurrence and development of neurological disorders. Modulating ferroptosis may have therapeutic potential in nervous system diseases. Therefore, TMTbased proteomic analysis in HT-22 cells was performed to identify erastin-induced differentially expressed proteins. The calcium-transporting ATP2B3 (ATP2B3) was screened as a target protein. ATP2B3 knockdown markedly alleviated the erastin-induced decrease in cell viability and elevated ROS (p < 0.01) and reversed the up-regulation of oxidative stress-related proteins polyubiquitin-binding protein p62 (P62), nuclear factor erythroid 2-related factor2 (NRF2), heme oxygenase-1 (HO-1), and NAD(P)H quinone oxidoreductase-1 (NQO1) protein expression (p < 0.05 or p < 0.01) and the down-regulation of Kelch-like ECH-associated protein 1(KEAP1) protein expression (p < 0.01). Moreover, NRF2 knockdown, P62 inhibition, or KEAP1 overexpression rescued the erastin-induced decrease in cell viability (p < 0.05) and increase in ROS production (p < 0.01) in HT-22 cells, while simultaneous overexpression of NRF2 and P62 and knockdown of KEAP1 partially offset the relief effect of ATP2B3 inhibition. In addition, knockdown of ATP2B3, NRF2, and P62 and overexpression of KEAP1 significantly down-regulated erastin-induced high expression of the HO-1 protein, while HO-1 overexpression reversed the alleviating effects of ATP2B3 inhibition on the erastin-induced decrease in cell viability (p < 0.01) and increase in ROS production (p < 0.01) in HT-22 cells. Taken together, ATP2B3 inhibition mediates the alleviation of erastin-induced ferroptosis in HT-22 cells through the P62-KEAP1-NRF2-HO-1 pathway.