Achieving Life through Death: Redox Biology of Lipid Peroxidation in Ferroptosis

Role of iron in brain development, aging, and neurodegenerative diseases

It is now understood that iron crosses the blood-brain barrier via a complex metabolic regulatory network and participates in diverse critical biological processes within the central nervous system, including oxygen transport, energy metabolism, and the synthesis and catabolism of myelin and neurotransmitters. During brain development, iron is distributed throughout the brain, playing a pivotal role in key processes such as neuronal development, myelination, and neurotransmitter synthesis. In physiological aging, iron can selectively accumulate in specific brain regions, impacting cognitive function and leading to intracellular redox imbalance, mitochondrial dysfunction, and lipid peroxidation, thereby accelerating aging and associated pathologies. Furthermore, brain iron accumulation may be a primary contributor to neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Comprehending the role of iron in brain development, aging, and neurodegenerative diseases, utilizing iron-sensitive Magnetic Resonance Imaging (MRI) technology for timely detection or prediction of abnormal neurological states, and implementing appropriate interventions may be instrumental in preserving normal central nervous system function.

Antioxidants in cancer therapy mitigating lipid peroxidation without compromising treatment through nanotechnology

BACKGROUND

Cancer treatments often exploit oxidative stress to selectively kill tumour cells by disrupting their lipid peroxidation membranes and inhibiting antioxidant enzymes. However, lipid peroxidation plays a dual role in cancer progression, acting as both a tumour promoter and a suppressor. Balancing oxidative stress through antioxidant therapy remains a challenge, as excessive antioxidant activity may compromise the efficacy of chemotherapy and radiotherapy.

AIM

This review explores the role of antioxidants in mitigating lipid peroxidation in cancer therapy while maintaining treatment efficacy. It highlights recent advancements in nanotechnology-based targeted antioxidant delivery to optimize therapeutic outcomes.

METHODS

A comprehensive literature review was conducted using reputable databases, including PubMed, Scopus, Web of Science, and ScienceDirect. The search focused on publications from the past five years (2020-2025), supplemented by relevant studies from earlier years. Keywords such as "antioxidants," "lipid peroxidation," "nanotechnology in cancer therapy," and "oxidative stress" were utilized. Relevant articles were critically analysed, and graphical illustrations were created.

RESULTS

Emerging evidence suggests that nanoparticles, including liposomes, polymeric nanoparticles, metal-organic frameworks, and others, can effectively encapsulate and control the release of antioxidants in tumour cells while minimizing systemic toxicity. Stimuli-responsive carriers with tumour-specific targeting mechanisms further enhance antioxidant delivery. Studies indicate that these strategies help preserve normal cells, mitigate oxidative stress-related damage, and improve treatment efficacy. However, challenges such as bioavailability, stability, and potential interactions with standard therapies remain.

CONCLUSION

Integrating nanotechnology with antioxidant-based interventions presents a promising approach for optimizing cancer therapy. Future research should focus on refining lipid peroxidation modulation strategies, assessing oxidative stress profiles during treatment, and employing biomarkers to determine optimal antioxidant dosing. A balanced approach to antioxidant use may enhance therapeutic efficacy while minimizing adverse effects.

Oxidized low-density lipoprotein induced ferroptosis in nucleus pulposus cell contributes to intervertebral disc degeneration via LOX-1/NF-κB/NOX signal

Oxidized low-density lipoprotein (oxLDL) activates the NF-κB signaling pathway through LOX-1, contributing to intervertebral disc degeneration (IVDD). Ferroptosis, a lipid peroxidation-driven cell death, is implicated in IVDD. This study investigates the role of ferroptosis in oxLDL-induced IVDD. Nucleus pulposus cells (NPCs) were treated with oxLDL, and ferroptosis and NF-κB p65 nuclear translocation were assessed. Bioinformatics analysis, silencing experiments, and inhibitors were used to validate the findings. In oxLDL-treated NPCs, LOX-1 and ferroptosis markers (MDA, Fe2+, lipid ROS) increased, while GSH decreased. These effects were mitigated by Liproxstatin-1 or shLOX-1. NF-κB p65 bound to LOX-1 and NOX1 promoters, forming a positive feedback loop. VAS2870 and Schisantherin A improved NPC viability and reduced ferroptosis. A mouse model showed worsening IVDD and ferroptosis over time. Clinical tissues revealed a strong correlation between LOX-1 and ferroptosis markers. oxLDL induces ferroptosis in NPCs via the LOX-1/NF-κB/NOX loop, advancing IVDD. Disrupting this loop in mice mitigated IVDD, highlighting the therapeutic potential of targeting this pathway.

Gene Expression Profiling Identifies CAV1, CD44, and TFRC as Potential Diagnostic Markers and Therapeutic Targets for Multiple Myeloma

Multiple myeloma (MM) is a highly malignant hematological tumor with a low overall survival rate, making the identification of innovative prognostic markers essential due to its complex and heterogeneous nature. Ferroptosis, an iron-dependent form of cell death driven by lipid peroxidation, is now recognized as crucial in tumor development and progression. Consequently, ferroptosis-related genes (FRGs) are emerging as promising therapeutic targets and prognostic indicators. However, the specific roles and predictive value of FRGs in MM still remain unclear. The current study was therefore conceived to examine the possible involvement of FRGs in MM. FRGs data was obtained from the FerrDb resource. The datasets GSE133346 and GSE166122, sourced from the Gene Expression Omnibus (GEO), provided gene expression data for both healthy and MM individuals. The differentially expressed-FRGs (DE-FRGs) were identified using the limma and DESeq2 packages in R. Functional pathways were analyzed through Gene Ontology (GO) and KEGG enrichment analyses. The miRWalk database was used for miRNA association and enrichment analysis with hub genes. Prognosis-related genes were evaluated using Kaplan-Meier survival analyses. We identified 1400 differentially expressed genes and cross-referenced them with FRGs, ultimately selecting 17 as DE-FRGs or hub genes. GO analysis revealed that the primary enriched functions of these hub genes are sister chromatid segregation, condensed chromosome centromeric region, C-C chemokine receptor activity, and C-C chemokine binding. KEGG pathway analysis showed that these overlapped genes were enriched in several pathways, including cell cycle, viral protein interaction with cytokine and cytokine receptor, as well as breast and prostate cancers involved pathways. Furthermore, significant enrichment was observed in glycolysis, gluconeogenesis, and the citrate cycle pathways based on miRNAs association with the candidate genes. The CAV1, CD44, TFRC, DPP4, and GJA1 are identified as top five significant hub DE-FRGs based on protein-protein interaction (PPI) analysis from multiple resources. Survival analysis eventually identified CAV1, CD44, and TFRC as the top-ranked DE-FRGs associated with overall survival, underscoring their crucial role in MM. This study identifies CAV1, CD44, and TFRC as key FRGs associated with the prognosis of MM, suggesting their potential as valuable prognostic markers and therapeutic targets to improve patient outcomes.

Ferroptosis in organ fibrosis: Mechanisms and therapeutic approaches

Ferroptosis, a form of iron-dependent regulated cell death, has emerged as a critical mechanism in the pathogenesis of organ fibrosis. This review aims to provide an overview of the molecular mechanisms underlying ferroptosis and its contribution to fibrosis in various organs, including the liver, lung, heart, and kidneys. We explore how dysregulated iron metabolism, lipid peroxidation, and oxidative stress contribute to ferroptosis and subsequent tissue damage, promoting the progression of fibrosis. In addition, we highlight the complex interplay between ferroptosis and other cellular processes such as apoptosis, necrosis, and inflammation in the fibrotic microenvironment. Furthermore, this review discusses current therapeutic strategies targeting ferroptosis, including iron chelation, antioxidants, and modulators of lipid peroxidation. We also examine ongoing clinical and preclinical studies aimed at translating these findings into viable treatments for fibrotic diseases. Understanding the role of ferroptosis in organ fibrosis offers novel therapeutic opportunities, with the potential to mitigate disease progression and improve patient outcomes.

Research progress of cPLA2 in cardiovascular diseases (Review)

Cytoplasmic phospholipase A2 (cPLA2) is a vital member of the PLA2 family. Studies have demonstrated that cPLA2 plays a key role in various inflammatory‑related diseases and cancers. However, limited research has focused on cPLA2 in cardiovascular diseases. The present review discussed and summarized the research progress on cPLA2 in atherosclerosis, cardiomyopathy, myocardial ischemia‑reperfusion injury and other related conditions. It also highlighted the critical molecular mechanisms by which cPLA2 regulates the pathophysiological processes of vascular endothelial cells, platelets and myocardial cells in cardiovascular diseases. Current studies confirm that cPLA2 plays an important role in cardiovascular diseases and has the potential to become a therapeutic target for the diagnosis, treatment evaluation and prognosis of these conditions. The present review systematically explored the significant role of cPLA2 in cardiovascular diseases and elaborated on its underlying molecular mechanisms. The findings aimed to refine the theoretical understanding of cardiovascular disease pathogenesis and provide a foundation for developing novel treatment strategies.

Ferroptosis: a potential therapeutic target in cardio-cerebrovascular diseases

Cardio-cerebrovascular diseases (CCVDs) are the leading cause of global mortality, yet effective treatment options remain limited. Ferroptosis, a novel form of regulated cell death, has emerged as a critical player in various CCVDs, including atherosclerosis, myocardial infarction, ischemia-reperfusion injury, cardiomyopathy, and ischemic/hemorrhagic strokes. This review highlights the core mechanisms of ferroptosis, its pathological implications in CCVDs, and the therapeutic potential of targeting this process. Additionally, it explores the role of Chinese herbal medicines (CHMs) in mitigating ferroptosis, offering novel therapeutic strategies for CCVDs management. Ferroptosis is regulated by several key pathways. The GPX4-GSH-System Xc- axis is central to ferroptosis execution, involving GPX4 using GSH to neutralize lipid peroxides, with system Xc- being crucial for GSH synthesis. The NAD(P)H/FSP1/CoQ10 axis involves FSP1 regenerating CoQ10 via NAD(P)H, inhibiting lipid peroxidation independently of GPX4. Lipid peroxidation, driven by PUFAs and enzymes like ACSL4 and LPCAT3, and iron metabolism, regulated by proteins like TfR1 and ferritin, are also crucial for ferroptosis. Inhibiting ferroptosis shows promise in managing CCVDs. In atherosclerosis, ferroptosis inhibitors reduce iron accumulation and lipid peroxidation. In myocardial infarction, inhibitors protect cardiomyocytes by preserving GPX4 and SLC7A11 levels. In ischemia-reperfusion injury, targeting ferroptosis reduces myocardial and cerebral damage. In diabetic cardiomyopathy, Nrf2 activators alleviate oxidative stress and iron metabolism irregularities. CHMs offer natural compounds that mitigate ferroptosis. They possess antioxidant properties, chelate iron, and modulate signaling pathways like Nrf2 and AMPK. For example, Salvia miltiorrhiza and Astragalus membranaceus reduce oxidative stress, while some CHMs chelate iron, reducing its availability for ferroptosis. In conclusion, ferroptosis plays a pivotal role in CCVDs, and targeting it offers novel therapeutic avenues. CHMs show promise in reducing ferroptosis and improving patient outcomes. Future research should explore combination therapies and further elucidate the molecular interactions in ferroptosis.

Natural flavonoids from herbs and nutraceuticals as ferroptosis inhibitors in central nervous system diseases: current preclinical evidence and future perspectives

Flavonoids are a class of important polyphenolic compounds, renowned for their antioxidant properties. However, recent studies have uncovered an additional function of these natural flavonoids: their ability to inhibit ferroptosis. Ferroptosis is a key mechanism driving cell death in central nervous system (CNS) diseases, including both acute injuries and chronic neurodegenerative disorders, characterized by iron overload-induced lipid peroxidation and dysfunction of the antioxidant defense system. This review discusses the therapeutic potential of natural flavonoids from herbs and nutraceuticals as ferroptosis inhibitors in CNS diseases, focusing on their molecular mechanisms, summarizing findings from preclinical animal models, and providing insights for clinical translation. We specifically highlight natural flavonoids such as Baicalin, Baicalein, Chrysin, Vitexin, Galangin, Quercetin, Isoquercetin, Eriodictyol, Proanthocyanidin, (-)-epigallocatechin-3-gallate, Dihydromyricetin, Soybean Isoflavones, Calycosin, Icariside II, and Safflower Yellow, which have shown promising results in animal models of acute CNS injuries, including ischemic stroke, cerebral ischemia-reperfusion injury, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, and spinal cord injury. Among these, Baicalin and its precursor Baicalein stand out due to extensive research and favorable outcomes in acute injury models. Mechanistically, these flavonoids not only regulate the Nrf2/ARE pathway and activate GPX4/GSH-related antioxidant pathways but also modulate iron metabolism proteins, thereby alleviating iron overload and inhibiting ferroptosis. While flavonoids show promise as ferroptosis inhibitors for CNS diseases, especially in acute injury settings, further studies are needed to evaluate their efficacy, safety, pharmacokinetics, and blood-brain barrier penetration for clinical application.

Cordycepin ameliorates diabetic nephropathy injury by activating the SLC7A11/GPX4 pathway

BACKGROUND

Cordycepin (CRD) has been identified to alleviate diabetes-induced injuries and complications including diabetic nephropathy (DN). Here, this work focused on probing the specific effects and potential mechanisms of CRD on DN progression.

METHODS

High glucose (HG)-induced mouse podocyte cell line (MPC5) was used for in vitro functional analyses. Cell proliferation and apoptosis were determined using cell counting kit-8 assay, 5-ethynyl-2'-deoxyuridine assay, and flow cytometry, respectively. ELISA analysis detected inflammatory factors. Cell ferroptosis was assessed by measuring the levels of Fe2+, glutathione, reactive oxygen species, and malonaldehyde.

RESULTS

CRD treatment suppressed HG-induced apoptosis, inflammation, and ferroptosis in podocytes. CRD treatment elevated SLC7A11 and GPX4 expression in HG-treated podocytes. The overexpression of SLC7A11 or GPX4 suppressed HG-evoked apoptosis, inflammation, and ferroptosis in podocytes. Moreover, the silencing of SLC7A11 or GPX4 abolished the protective effects of CRD on HG-treated podocytes. Moreover, CRD ameliorated renal structure injury and inflammation in STZ-induced diabetic mice by modulating SLC7A11 or GPX4 expression.

CONCLUSIONS

Cordycepin suppressed HG-induced apoptosis, inflammation, and ferroptosis in podocytes in vitro, and ameliorated renal injury and inflammation in STZ-induced diabetic mice by activating the SLC7A11/GPX4 pathway.

Epithelial-mesenchymal transition promotes metabolic reprogramming to suppress ferroptosis

Epithelial-mesenchymal transition (EMT) is a cellular de-differentiation process that provides cells with the increased plasticity and stem cell-like traits required during embryonic development, tissue remodeling, wound healing and metastasis. Morphologically, EMT confers tumor cells with fibroblast-like properties that lead to the rearrangement of cytoskeleton (loss of stiffness) and decrease of membrane rigidity by incorporating high level of poly-unsaturated fatty acids (PUFA) in their phospholipid membrane. Although large amounts of PUFA in membrane reduces rigidity and offers capabilities for tumor cells with the unbridled ability to stretch, bend and twist in metastasis, these PUFA are highly susceptible to lipid peroxidation, which leads to the breakdown of membrane integrity and, ultimately results in ferroptosis. To escape the ferroptotic risk, EMT also triggers the rewiring of metabolic program, particularly in lipid metabolism, to enforce the epigenetic regulation of EMT and mitigate the potential damages from ferroptosis. Thus, the interplay among EMT, lipid metabolism, and ferroptosis highlights a new layer of intricated regulation in cancer biology and metastasis. Here we summarize the latest findings and discuss these mutual interactions. Finally, we provide perspectives of how these interplays contribute to cellular plasticity and ferroptosis resistance in metastatic tumor cells that can be explored for innovative therapeutic interventions.

Lipid metabolism in multiple myeloma: pathogenesis, therapeutic opportunities, and future directions

BACKGROUND

Multiple myeloma (MM) is a complex hematological malignancy characterized by the clonal expansion of plasma cells in the bone marrow. Emerging studies have emphasized the importance of lipid metabolism, which is closely associated with the survival, proliferation, and drug resistance of tumor cells. The hypoxic environment in the bone marrow (BM) contributes to metabolic reprogramming in MM cells, including alterations in metabolite levels, changes in metabolic enzyme activity, and metabolic shifts. Cancer cells possess the ability to adapt their metabolism in order to fulfill their continuously increasing energy demands. In this review, we will discuss the alterations in lipid metabolism during the development of MM, and their reciprocal interactions with the tumor microenvironment.

Ferroptosis: A New Strategy for the Treatment of Fibrotic Diseases

Ferroptosis is a new type of cell death characterized by iron dependence and the excessive accumulation of lipid reactive oxygen species (lipid ROS) that has gradually become better characterized. There is sufficient evidence indicating that ferroptosis is associated with a variety of human life activities and diseases, such as tumor suppression, ischemic organ injury, and degenerative disorders. Notably, ferroptosis is also involved in the initiation and development of fibrosis in various organs, including liver fibrosis, pulmonary fibrosis, renal fibrosis, and cardiac fibrosis, which is usually irreversible and refractory. Although a large number of patients with fibrosis urgently need to be treated, the current treatment options are still limited and unsatisfactory. Organ fibrosis involves a series of complex and orderly processes, such as parenchymal cell damage, recruitment of inflammatory cells and activation of fibroblasts, which ultimately leads to the accumulation of extracellular matrix (ECM) and the formation of fibrosis. An increasing number of studies have confirmed the close association between these pathological processes and ferroptosis. This review summarizes the role and function of ferroptosis in fibrosis and proposes several potential therapeutic strategies and pathways based on ferroptosis.

Discovery and optimization of 1,2,4-triazole derivatives as novel ferroptosis inhibitors

Ferroptosis is a novel form of regulated cell death characterized by iron-dependent lipid ROS accumulation, which is associated with various diseases, including acute organ injury, neurodegenerative disorders, and cancer. Pharmacological inhibition of ferroptosis has great potential for the treatment of these diseases. However, the clinical translation of many ferroptosis inhibitors is hindered by their inadequate activity or suboptimal pharmacokinetic profiles. In this study, several 1,2,4-triazole derivatives were identified as novel ferroptosis inhibitors through phenotypic screening of our in-house compound library. Among these compounds, NY-26 was found to significantly inhibit RSL3-induced ferroptosis in 786-O cells with nanomolar level (EC50 = 62 nM). The antiferroptotic activity of NY-26 was further validated across multiple cell lines. Mechanistic studies revealed that NY-26 inhibits ferroptosis through its intrinsic free radical-trapping antioxidant capacity. Additional results demonstrated that the triazole derivatives could effectively ameliorate ferroptosis-related pathological conditions in a mouse model of ConA-induced acute liver injury. Taken together, NY-26, tethering a novel 1,2,4-triazole scaffold, could be an effective ferroptosis inhibitor with great therapeutic potential for further investigation.

The LKB1-AMPK Signaling Axis Modulates Ferroptosis in Fibroblast-Like Synoviocytes Derived from Rheumatoid Arthritis

BACKGROUND/OBJECTIVES

Ferroptosis is a type of regulated cell death that involves iron-dependent accumulation of lipid peroxides. Because fibroblast-like synoviocytes (FLSs) in patients with rheumatoid arthritis (RA) have a hyperplastic and inflammatory phenotype, selective induction of FLS cell death is considered a potential treatment strategy for RA. Liver kinase B1 (LKB1)-activated AMP-activated protein kinase (AMPK) signaling regulates the inflammation and migration of RA FLSs, contributing to RA pathogenesis. Here, we aimed to determine the effect of LKB1 knockdown on the ferroptosis pathway in RA FLSs.

METHODS

Synovial tissues from patients with RA (n = 5) were transfected with siRNA targeting LKB1. Cell viability was evaluated via 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide (MTT) assay and Annexin V/7-aminoactinomycin D (7-AAD) staining. Ferroptosis was assessed using boron-dipyrromethene (BODIPY) lipid probes, a ferrous ion detection kit, and a glutathione detection assay. Expression of hallmarks of various cell death pathways was analyzed using western blot.

RESULTS

RA FLS cell death significantly increased after transfection with LKB1 siRNA (p < 0.01). Lipid peroxidation was upregulated and the expression levels of glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11) were suppressed in LKB1-deficient cells. Additionally, LKB1 inhibition made RA FLSs highly sensitive to ferroptosis. When RA FLSs were incubated with an activator of AMPK, LKB1 knockdown-mediated inhibition was restored through upregulated expression of GPX4 and SLC7A11.

CONCLUSIONS

these findings suggest that LKB1-AMPK signaling is essential to protect RA FLSs against ferroptosis.

The link between ferroptosis and autophagy in myocardial ischemia/reperfusion injury: new directions for therapy

Myocardial ischemia/reperfusion (I/R)-induced cell death, such as autophagy and ferroptosis, is a major contributor to cardiac injury. Regulating cell death may be key to mitigating myocardial ischemia/reperfusion injury (MI/RI). Autophagy is a crucial physiological process involving cellular self-digestion and compensation, responsible for degrading excess or malfunctioning long-lived proteins and organelles. During MI/RI, autophagy plays both "survival" and "death" roles. A growing body of research indicates that ferroptosis is a type of autophagy-dependent cell death. This article provides a comprehensive review of the functions of autophagy and ferroptosis in MI/RI, as well as the molecules mediating their interaction. Understanding the link between autophagy and ferroptosis may offer new therapeutic directions for MI/RI, bearing significant clinical implications.

Targeting Ferroptosis in Rare Neurological Disorders Including Pediatric Conditions: Innovations and Therapeutic Challenges

Ferroptosis, characterized by iron dependency and lipid peroxidation, has emerged as a key mechanism underlying neurodegeneration in rare neurological disorders. These conditions, often marked by significant therapeutic gaps and high unmet medical needs, present unique challenges for intervention development. This review examines the involvement of ferroptosis in rare neurological disease pathogenesis, focusing on its role in oxidative damage and neuronal dysfunction. We explore recent pharmacological advancements, including iron chelators, lipid peroxidation blockers, and antioxidant-based strategies, designed to target ferroptosis. While these approaches show promise, challenges such as disease heterogeneity, limited diagnostic tools, and small patient cohorts hinder progress. Furthermore, we discuss the translational and regulatory barriers to implementing ferroptosis-based therapies in clinical practice. By addressing these obstacles and fostering innovative solutions, this review underscores the potential of ferroptosis-targeting strategies to revolutionize treatment paradigms for rare neurological disorders.

Comprehensive analysis of ferroptosis-related genes reveals potential therapeutic targets in osteoporosis patients: a computational analysis and in vitro experiments

Background

Ferroptosis-related genes have been reported to play important roles in many diseases, but their molecular mechanisms in osteoporosis have not been elucidated.

Methods

Based on two independent GEO datasets (GSE35956 and GSE35958), and GSE35959 as the validation dataset, we comprehensively elucidated the pathological mechanism of ferroptosis-related genes in osteoporosis by GO analyses, KEGG analyses and a PPI network. Then, We used Western Blot (WB) and Quantitative real-time polymerase chain reaction (qPCR) to verify the expression level of KMT2D, a ferroptosis-related hub gene, in clinical samples. Subsequently, we predicted the upstream miRNA of KMT2D gene and analyzed the mechanism of KMT2D in osteoporosis, the potential prognostic value and its immune invasion of KMT2D in pan-cancer.

Results

This study identified KMT2D and MYCN, TP63, RELA, SOX2, and CDKN1A as key ferroptosis-related genes in osteoporotic cell aging. The independent dataset validated that the expression level of KMT2D was significantly upregulated in osteoporosis samples. The experimental verification results of qPCR and WB indicate that KMT2D is highly expressed in patients with osteoporosis. Further analysis revealed that the hsa-miR-204-5p-KMT2D axis may play an important role in the aging of osteoporotic cells. The analysis of KMT2D reveals that KMT2D may mainly play a role in the aging of osteoporotic cells through epigenetics and the value in pan-cancer.

Conclusion

The study provides a theoretical basis for the treatment of osteoporosis.

An Aggregation-induced Emission Probe to Detect the Viscosity Change in Lipid Droplets during Ferroptosis

Ferroptosis is a recently identified form of cell death characterized by iron-dependent lipid peroxidation. Understanding the effects of lipid peroxidation on cellular processes during ferroptosis requires insights into lipid droplets (LDs) and their viscosity changes. To gain further insights into the intricacies of ferroptosis, it is crucial to have a fluorescent probe that targets LDs and responds to changes in viscosity. In this study, we introduce a novel LD-targeting viscosity fluorescent probe named TQE, based on the principles of aggregation-induced emission (AIE). The probe displayed AIE characteristics in tetrahydrofuran, possessing a partition coefficient (logP) of 5.87. With increased viscosity, intramolecular rotation was restricted, leading to a remarkable 3.3-fold enhancement in emission. Notably, TQE exhibited robust resistance to photo-bleaching during cellular imaging, maintaining approximately 75% of its emission intensity even after 30 min of laser irradiation. Importantly, the AIEgen could not generate hydroxyl radicals when exposed to light for up to 3 h, suggesting the low photo-toxicity of TQE to cells. Leveraging these properties, we successfully employed the probe for fluorescent imaging of the viscosity change in LDs during ferroptosis.

Ehretia laevis mitigates paracetamol- induced hepatotoxicity by attenuating oxidative stress and inflammation in rats

Hepatotoxicity is caused due to intake of drug or any chemical above the therapeutic range or as overdose. Current therapies for the management of hepatotoxicity are associated with several side effects. The present study was envisaged to explore the hepatoprotective potential of Ehretia laevis (E. laevis) in paracetamol (PCM) induced hepatotoxicity. All the plant extracts and fractions were evaluated for antioxidant and antiproliferative potential using various in vitro assays. Hepatotoxicity was induced in rats using a standardized single oral dose of PCM (3 g/kg). The aqueous fraction of E. laevis (AFEL) exhibited significant antioxidant and antiproliferative activity as compared to methanol extract of E. laevis (MEEL) in vitro. Moreover, treatment with AFEL (25, 50 and 100 mg/kg) decreased serum hepatic markers, attenuate the oxidative stress, inflammation and histopathological changes. LC-MS analysis of AFEL showed the presence of rutin, quercetin and kaempferol. Rutin was found to be in higher concentration, therefore it was docked on TNF-α. Its overall binding mode supports its capability to make complex with TNF-α. The finding of the study suggested significant antioxidant, antiproliferative, and hepatoprotective potential of E. laevis in paracetamol induced hepatotoxicity which could be attributed to the presence of various polyphenols.

Absence of gut microbiota alleviates iron overload-induced colitis by modulating ferroptosis in mice

INTRODUCTION

Iron overload disrupts gut microbiota and induces ferroptosis, contributing to colitis. However, whether gut microbiota directly drives iron overload-induced colitis and its underlying mechanism remain unclear.

OBJECTIVES

The study aimed to explore whether gut microbiota can directly regulate iron overload-induced colitis and its underling mechanism.

METHODS

Male C57BL/6N mice were fed with ferrous sulfate to establish an iron overload model. Antibiotics and dextran sulfate sodium salt (DSS) were used to create germ-free and colitis models, respectively.

RESULTS

Results showed that iron overload caused disruption of systemic iron homeostasis via activating pro-inflammation response, which caused induction of ferroptosis and eventually resulted in colitis in mice. Notably, iron overload inhibited System Xc- and activated the nuclear factor E2-related factor 2/heme oxygenase-1 pathway, driving ferroptosis and colitis progression. Similar results were observed in mouse colon epithelial cells, which were treated with high doses ferric ammonium citrate. Additionally, iron overload exacerbated DSS-induced colitis by activating the ferroptosis and increasing harmful bacteria (e.g., Mucispirillum) abundance. Interestingly, eliminating gut microbiota attenuated iron overload-induced colitis, without affecting systemic inflammation through inhibiting ferroptosis of mice. Depletion of the gut microbiota partially mitigated the exacerbating effect of iron overload on DSS-induced colitis through inhibiting ferroptosis of mice.

CONCLUSION

Iron overload activates ferroptosis in colonic cells, increases the relative abundance of harmful bacteria, and exacerbates DSS-induced colitis in mice. Iron overload exacerbates DSS-induced ferroptosis and colitis in a microbiota-dependent manner. Targeting gut microbiota may offer new strategies for managing iron overload-induced colitis.

Protective effects of sulfated polysaccharides from Enteromorpha intestinalis on oxidative stress, liver iron overload and Ferroptosis in Zebra fish exposed to ethanol

The study investigates the protective effects of sulfated polysaccharides extracted from Enteromorpha intestinalis (EIP) against oxidative stress, liver iron overload, and ferroptosis in zebrafish exposed to ethanol, a model for alcohol-related liver disease (ALD). The extracted polysaccharides were characterized for sulfate and sugar content, molecular weight, and functional groups. Adult male zebrafish were divided into three groups: control, ethanol-exposed (EE) (0.2 % ethanol (v/v) in the water), and ethanol-exposed with EIP supplementation (1 % EIP incorporated into the basal diet) (EE+EIP) for 30 days. The study measured liver oxidative stress indexes, serum enzymological indexes, liver and serum lipid profiles, liver iron ion content, and expression of ferroptosis-related genes. Histological analysis was conducted to assess lipid accumulation and iron deposition in liver tissues. The findings indicate that EIP supplementation significantly mitigates ethanol-induced liver damage. Specifically, EIP reduced malondialdehyde levels, increased antioxidant enzyme and non-enzymatic antioxidant activity, and decreased iron ion accumulation and the area of iron granules in the liver tissue. Additionally, EIP treatment lowered lipids levels and aminotransferase enzyme activity in the serum. In the ALD model, EIP inhibited ethanol-induced ferroptosis by modulating the expression of key genes: it decreased the expression of transferrin (tf), transferrin receptor (tfr), ferroportin (fpn), and ferritin heavy chain (fth), while increasing the expression of glutathione peroxidase 4 (gpx4) and solute carrier family 7 member 11 (slc7a11). EIP has protective effects against ethanol-induced liver injury in zebrafish, offering a foundation for further research into its hepatoprotective action and potential application in preventing and treating ALD.

Calpain-1 Up-Regulation Promotes Bleomycin-Induced Pulmonary Fibrosis by Activating Ferroptosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and fatal disease. Calpain-1 is an effective therapeutic target for vascular endothelial dysfunction and pulmonary hypertension. However, the role of calpain-1 in bleomycin (BLM)-induced IPF has not been defined. The aim of this study was to assess the targeting of calpain-1 by activating ferroptosis in BLM-treated knockout mice and murine lung epithelial-12 cells. The role of calpain-1 in the regulation of IPF was investigated using a BLM-induced IPF mouse model. The results of this study showed that increased expression of calpain-1 was accompanied by increased fibrosis, lipid peroxidation, iron ion accumulation, and Yes-associated protein (YAP) levels and decreased levels of phosphorylated adenosine 5'-monophosphate-activated protein kinase (p-AMPK) in BLM-induced IPF. MDL-28170 (calpain-1 inhibition) treatment and calpain-1 knockdown alleviated ferroptosis and IPF induced by BLM. Overexpression of calpain-1 in murine lung epithelial-12 cells further exacerbated iron accumulation and IPF. Mechanistically, lentivirus-mediated up-regulation of calpain-1 inhibited AMPK activity and promoted the nuclear translocation of YAP, leading to high levels of acyl-CoA synthetase long-chain family 4 and transferrin receptor protein 1 and triggering a ferroptosis response that ultimately exacerbated BLM-induced lung fibrosis. Calpain-1 inhibition reversed these results and ameliorated BLM-induced IPF. In conclusion, these findings suggest that the calpain-1-acyl-CoA synthetase long-chain family 4-transferrin receptor protein 1-ferroptosis-positive regulatory axis contributes to BLM-induced IPF, which indicates that calpain-1 has potential therapeutic value for the treatment of IPF.

Engineering Strain-Defects to Enhance Enzymatic Therapy and Induce Ferroptosis

The effect of mimetic enzyme catalysis is often limited by insufficient activity and a single therapy is not sufficient to meet the application requirements. In this study, a multifunctional nanozyme, MMSR-pS-PEG, is designed and fabricated by modifying poly (ethylene glycol) grafted phosphorylated serine (pS-PEG) on mesoporous hollow MnMoOx spheres, followed by loading sorafenib (SRF) into the pores. Strain engineering-induced oxygen defects endow the nanozyme with enhanced dual-enzymatic activity to mimic catalase and oxidase-like activities, which catalyze the conversion of endogenous H2O2 into oxygen and subsequently into superoxide ions in the acidic tumor microenvironment. Moreover, as an n-type semiconductor, MnMoOx generates reactive oxygen species by separating electrons and holes upon ultrasonic irradiation and simultaneously deplete glutathione by holes, thereby further augmenting its catalytic effect. As a ferroptosis inducer, SRF restrains the system xc - and indirectly inhibits glutathione synthesis, synergistically interacting with the nanozyme to stimulate ferroptosis by promoting lipid peroxidation and accumulation and the downregulation of glutathione peroxidase 4. These results provide valuable insights into the design of enzymatic therapy with high performance and highlight a promising approach for the synergism of ferroptosis and enzymatic tumor therapy.

Pathological insights into cell death pathways in diabetic wound healing

Diabetic foot ulcers (DFUs) are a microvascular complication that affects almost 21 % of the diabetic population. DFUs are characterized by lower limb abnormalities, chronic inflammation, and a heightened hypoxic environment. The challenge of healing these chronic wounds arises from impaired blood flow, neuropathy, and dysregulated cell death processes. The pathogenesis of DFUs involves intricate mechanisms of programmed cell death (PCD) in different cell types, which include keratinocytes, fibroblasts, and endothelial cells. The modes of cell death comprise apoptosis, autophagy, ferroptosis, pyroptosis, and NETosis, each defined by distinct biochemical hallmarks. These diverse mechanisms contribute to tissue injury by inducing neutrophil extracellular traps and generating cellular stressors like endoplasmic reticulum stress, oxidative stress, and inflammation. Through a comprehensive review of experimental studies identified from literature databases, this review synthesizes current knowledge on the critical signaling cascades implicated in programmed cell death within the context of diabetic foot ulcer pathology.

GPX4 Promoter Hypermethylation Induced by Ischemia/Reperfusion Injury Regulates Hepatocytic Ferroptosis

Background and Aims

Glutathione peroxidase 4 (GPX4) is a key factor in ferroptosis, which is involved in ischemia-reperfusion injury. However, little is known about its role in hepatic ischemia-reperfusion injury (HIRI). This study aimed to investigate the role of GPX4 methylation in ferroptosis during HIRI.

Methods

For the in vitro experiments, an oxygen and glucose deprivation cell model was established. For the in vivo experiments, an ischemia-reperfusion model was created by subjecting mice to simulated HIRI. Ferroptosis occurrence, GPX4 promoter methylation, and global methylation levels were then assessed.

Results

Ferroptosis was observed in oxygen and glucose deprivation, characterized by a significant decrease in cellular viability (P < 0.05), an increase in lipid peroxidation (P < 0.01), iron overload (P < 0.05), and down-regulation of GPX4 (P < 0.05). This ferroptosis was exacerbated by GPX4 knockdown (P < 0.01) and mitigated by exogenous glutathione (P < 0.01). Similarly, ferroptosis was evident in mice subjected to HIRI, with a down-regulation of GPX4 mRNA and protein expression (all P < 0.01), and an upregulation of acyl-CoA synthetase long-chain family member 4 mRNA and protein (all P < 0.01), as well as prostaglandin-endoperoxide synthase 2 mRNA and protein expression (all P < 0.05). Methylation levels increased, evidenced by upregulation of DNA methylation transferase expression (P < 0.05) and down-regulation of Ten-eleven translocation family demethylases (P < 0.01), along with an upregulation of GPX4 promoter methylation.

Conclusions

Ferroptosis may be the primary mode of cell death in hepatocytes following ischemia-reperfusion injury. The methylation of the GPX4 promoter and elevated levels of global hepatic methylation are involved in the regulation of ferroptosis.

An Actual Insight into the Pathogenic Pathways of Ankylosing Spondylitis

Spondyloarthritis refers to a broad group of conditions that include ankylosing spondylitis, psoriatic arthritis, reactive arthritis, and enteropathic arthritis associated with Crohn's disease or ulcerative colitis. They have been classified by the ASAS group (ASsessment in Ankylosing Spondylitis) into axial spondyloarthritis and peripheral spondyloarthritis. Common features include the absence of autoantibodies, genetic predisposition, and clinical aspects such as axial joint involvement, peripheral manifestations, and extra-articular involvement. However, the pathogenic mechanisms remain complex and incompletely elucidated, despite the fact that the specialized literature has described several pathways that act in synergy: genetic predisposition, environmental factors (infections and mechanical stress), or innate and acquired immune mechanisms. Finally, an inflammatory response is triggered by the recruitment of a large number of inflammatory cells and the release of innate cytokines in the affected areas: joints or periarticular or extraarticular tissues. The current article aims to update and systematize the knowledge accumulated so far on this topic, focusing on the mechanisms that have been involved in the onset, progression, and severity of ankylosing spondylitis.

The PRMT6/STAT1/ACSL1 axis promotes ferroptosis in diabetic nephropathy

Hyperglycaemia-induced ferroptosis is a significant contributor to kidney dysfunction in diabetic nephropathy (DN) patients. In addition, targeting ferroptosis has clinical implications for the treatment of DN. However, effective therapeutic targets for ferroptosis have not been identified. In this study, we aimed to explore the precise role of protein arginine methyltransferase 6 (PRMT6) in regulating ferroptosis in DN. In the present study, we utilized a mouse DN model consisting of both wild-type and PRMT6-knockout (PRMT6-/-) mice. Transcriptomic and lipidomic analyses, along with various molecular biological methodologies, were used to determine the potential mechanism by which PRMT6 regulates ferroptosis in DN. Our results indicate that PRMT6 downregulation participates in kidney dysfunction and renal cell death via the modulation of ferroptosis in DN. Moreover, PRMT6 reduction induced lipid peroxidation by upregulating acyl-CoA synthetase long-chain family member 1 (ACSL1) expression, ultimately contributing to ferroptosis. Furthermore, we investigated the molecular mechanism by which PRMT6 interacts with signal transducer and activator of transcription 1 (STAT1) to jointly regulate ACSL1 transcription. Additionally, treatment with the STAT1-specific inhibitor fludarabine delayed DN progression. Furthermore, we observed that PRMT6 and STAT1 synergistically regulate ACSL1 transcription to mediate ferroptosis in hyperglycaemic cells. Our study demonstrated that PRMT6 and STAT1 comodulate ACSL1 transcription to induce the production of phospholipid-polyunsaturated fatty acids (PL-PUFAs), thus participating in ferroptosis in DN. These findings suggest that the PRMT6/STAT1/ACSL1 axis is a new therapeutic target for the prevention and treatment of DN.

Macrophage iron dyshomeostasis promotes aging-related renal fibrosis

Renal aging, marked by the accumulation of senescent cells and chronic low-grade inflammation, leads to renal interstitial fibrosis and impaired function. In this study, we investigate the role of macrophages, a key regulator of inflammation, in renal aging by analyzing kidney single-cell RNA sequencing data of C57BL/6J mice from 8 weeks to 24 months. Our findings elucidate the dynamic changes in the proportion of kidney cell types during renal aging and reveal that increased macrophage infiltration contributes to chronic low-grade inflammation, with these macrophages exhibiting senescence and activation of ferroptosis signaling. CellChat analysis indicates enhanced communications between macrophages and tubular cells during aging. Suppressing ferroptosis alleviates macrophage-mediated tubular partial epithelial-mesenchymal transition in vitro, thereby mitigating the expression of fibrosis-related genes. Using SCENIC analysis, we infer Stat1 as a key age-related transcription factor promoting iron dyshomeostasis and ferroptosis in macrophages by regulating the expression of Pcbp1, an iron chaperone protein that inhibits ferroptosis. Furthermore, through virtual screening and molecular docking from a library of anti-aging compounds, we construct a docking model targeting Pcbp1, which indicates that the natural small molecule compound Rutin can suppress macrophage senescence and ferroptosis by preserving Pcbp1. In summary, our study underscores the crucial role of macrophage iron dyshomeostasis and ferroptosis in renal aging. Our results also suggest Pcbp1 as an intervention target in aging-related renal fibrosis and highlight Rutin as a potential therapeutic agent in mitigating age-related renal chronic low-grade inflammation and fibrosis.

Unlocking ferroptosis in prostate cancer - the road to novel therapies and imaging markers

Ferroptosis is a distinct form of regulated cell death that is predominantly driven by the build-up of intracellular iron and lipid peroxides. Ferroptosis suppression is widely accepted to contribute to the pathogenesis of several tumours including prostate cancer. Results from some studies reported that prostate cancer cells can be highly susceptible to ferroptosis inducers, providing potential for an interesting new avenue of therapeutic intervention for advanced prostate cancer. In this Perspective, we describe novel molecular underpinnings and metabolic drivers of ferroptosis, analyse the functions and mechanisms of ferroptosis in tumours, and highlight prostate cancer-specific susceptibilities to ferroptosis by connecting ferroptosis pathways to the distinctive metabolic reprogramming of prostate cancer cells. Leveraging these novel mechanistic insights could provide innovative therapeutic opportunities in which ferroptosis induction augments the efficacy of currently available prostate cancer treatment regimens, pending the elimination of major bottlenecks for the clinical translation of these treatment combinations, such as the development of clinical-grade inhibitors of the anti-ferroptotic enzymes as well as non-invasive biomarkers of ferroptosis. These biomarkers could be exploited for diagnostic imaging and treatment decision-making.

Iron chelators as mitophagy agents: Potential and limitations

Mitochondrial autophagy (mitophagy) is very important process for the maintenance of cellular homeostasis, functionality and survival. Its dysregulation is associated with high risk and progression numerous serious diseases (e.g., oncological, neurodegenerative and cardiovascular ones). Therefore, targeting mitophagy mechanisms is very hot topic in the biological and medicinal research. The interrelationships between the regulation of mitophagy and iron homeostasis are now becoming apparent. In short, mitochondria are central point for the regulation of iron homeostasis, but change in intracellular cheatable iron level can induce/repress mitophagy. In this review, relationships between iron homeostasis and mitophagy are thoroughly discussed and described. Also, therapeutic applicability of mitophagy chelators in the context of individual diseases is comprehensively and critically evaluated.

Targeting ferroptosis with the lipoxygenase inhibitor PTC-041 as a therapeutic strategy for the treatment of Parkinson's disease

Parkinson's disease is the second most common neurodegenerative disorder, affecting nearly 10 million people worldwide. Ferroptosis, a recently identified form of regulated cell death characterized by 15-lipoxygenase-mediated hydroperoxidation of membrane lipids, has been implicated in neurodegenerative disorders including amyotrophic lateral sclerosis and Parkinson's disease. Pharmacological inhibition of 15 -lipoxygenase to prevent iron- and lipid peroxidation-associated ferroptotic cell death is a rational strategy for the treatment of Parkinson's disease. We report here the characterization of PTC-041 as an anti-ferroptotic reductive lipoxygenase inhibitor developed for the treatment of Parkinson's disease. In these studies, PTC-041 potently protects primary human Parkinson's disease patient-derived fibroblasts from lipid peroxidation and subsequent ferroptotic cell death and prevents ferroptosis-related neuronal loss and astrogliosis in primary rat neuronal cultures. Additionally, PTC-041 prevents ferroptotic-mediated α-synuclein protein aggregation and nitrosylation in vitro, suggesting a potential role for anti-ferroptotic lipoxygenase inhibitors in mitigating pathogenic aspects of synucleinopathies such as Parkinson's disease. We further found that PTC-041 protects against synucleinopathy in vivo, demonstrating that PTC-041 treatment of Line 61 transgenic mice protects against α-synuclein aggregation and phosphorylation as well as prevents associated neuronal and non-neuronal cell death. Finally, we show that. PTC-041 protects against 6-hydroxydopamine-induced motor deficits in a hemiparkinsonian rat model, further validating the potential therapeutic benefits of lipoxygenase inhibitors in the treatment of Parkinson's disease.

Research progress of ferroptosis in female infertility

Ferroptosis is a novel type of programmed cell death dependent on iron and characterized by the accumulation of lipid peroxides in cells and is closely related to various diseases. Female infertility is a global health concern, which is associated with a variety of factors. The etiology remains unknown in many women with infertility. With further investigation into the pathogenesis of infertility, a growing number of studies have demonstrated the close connections between infertility and ferroptosis. Through a literature review, it is found that ferroptosis is closely involved in endometriosis- and polycystic ovarian syndrome (PCOS)-associated infertility and tubal factor infertility. Iron overload increases the resistance to ferroptosis, and ferroptosis in some cells accelerates endometrial lesion growth. Moreover, iron overload may be hazardous to oocytes. This review may shed some light on the diagnosis and treatment of female infertility.

Ferroptosis in health and disease

Ferroptosis is a pervasive non-apoptotic form of cell death highly relevant in various degenerative diseases and malignancies. The hallmark of ferroptosis is uncontrolled and overwhelming peroxidation of polyunsaturated fatty acids contained in membrane phospholipids, which eventually leads to rupture of the plasma membrane. Ferroptosis is unique in that it is essentially a spontaneous, uncatalyzed chemical process based on perturbed iron and redox homeostasis contributing to the cell death process, but that it is nonetheless modulated by many metabolic nodes that impinge on the cells' susceptibility to ferroptosis. Among the various nodes affecting ferroptosis sensitivity, several have emerged as promising candidates for pharmacological intervention, rendering ferroptosis-related proteins attractive targets for the treatment of numerous currently incurable diseases. Herein, the current members of a Germany-wide research consortium focusing on ferroptosis research, as well as key external experts in ferroptosis who have made seminal contributions to this rapidly growing and exciting field of research, have gathered to provide a comprehensive, state-of-the-art review on ferroptosis. Specific topics include: basic mechanisms, in vivo relevance, specialized methodologies, chemical and pharmacological tools, and the potential contribution of ferroptosis to disease etiopathology and progression. We hope that this article will not only provide established scientists and newcomers to the field with an overview of the multiple facets of ferroptosis, but also encourage additional efforts to characterize further molecular pathways modulating ferroptosis, with the ultimate goal to develop novel pharmacotherapies to tackle the various diseases associated with - or caused by - ferroptosis.

Oxidation Kinetics of Fluorescent Membrane Lipid Peroxidation Indicators

The oxidation of the cellular membrane through lipid peroxidation (LPO) is linked to aging and disease. Despite the physiological importance, the chemical mechanisms underlying LPO and oxidative reactions in membranes in general remain incompletely understood, and challenges exist in translating LPO inhibitor efficacies from in vitro to in vivo. The complexity of LPO, including multiple oxidation reactions in complex membrane environments and the difficulty in quantifying reaction kinetics, underlies these difficulties. In this work, we developed a robust and straightforward method for quantifying the oxidation rate kinetics of fluorescent molecules and determined the oxidation kinetics of widely fluorophores used as indicators of membrane LPO, diphenylhexatriene (DPH), BODIPY-C11, and Liperfluo. The measurement is initiated by lipoxygenase, which provides chemical specificity and enables a straightforward interpretation of oxidation kinetics. Our results reveal that the membrane composition significantly impacts the observed kinetics oxidation in DPH and BODIPY-C11 but not Liperfluo. Reaction mechanisms for their lipid peroxide-induced oxidation are proposed. This work provides a foundation for the quantitative analysis of LPO with fluorescence and extricating the complexity of oxidation reactions within membranes.

Ferroptosis-A Shared Mechanism for Parkinson's Disease and Type 2 Diabetes

Type 2 diabetes (T2D) and Parkinson's disease (PD) are the two most frequent age-related chronic diseases. There are many similarities between the two diseases: both are chronic diseases; both are the result of a decrease in a specific substance-insulin in T2D and dopamine in PD; and both are caused by the destruction of specific cells-beta pancreatic cells in T2D and dopaminergic neurons in PD. Recent epidemiological and experimental studies have found that there are common underlying mechanisms in the pathophysiology of T2D and PD: chronic inflammation, mitochondrial dysfunction, impaired protein handling and ferroptosis. Epidemiological research has indicated that there is a higher risk of PD in individuals with T2D. Moreover, clinical studies have observed that the symptoms of Parkinson's disease worsen significantly after the onset of T2D. This article provides an up-to-date review on the intricate interplay between oxidative stress, reactive oxygen species (ROS) and ferroptosis in PD and T2D. By understanding the shared molecular pathways and how they can be modulated, we can develop more effective therapies, or we can repurpose existing drugs to improve patient outcomes in both disorders.

Cholesterol-ferroptosis nexus: Unveiling novel cancer therapeutic avenues

Ferroptosis, a novel form of regulated cell death characterized by iron-mediated lipid peroxidation, holds immense potential in cancer therapeutics due to its role in tumor progression and resistance. This review predominantly explores the intricate relationship between ferroptosis and cholesterol metabolism pathways, mainly focusing on the cholesterol biosynthesis pathway. This review highlights the therapeutic implications of targeting cholesterol metabolism pathways for cancer treatment by delving into the mechanisms underlying ferroptosis regulation. Strategies such as inhibiting HMG-CoA reductase and suppressing squalene synthesis offer promising avenues for inducing ferroptosis in cancer cells. Moreover, insights into targeting the 7-dehydrocholesterol pathway provide novel perspectives on modulating ferroptosis susceptibility and managing ferroptosis-associated diseases. Understanding the interplay between ferroptosis and cholesterol metabolism pathways underscores the potential of lipid metabolism modulation as an innovative therapeutic approach in cancer treatment.

Ten "Cheat Codes" for Measuring Oxidative Stress in Humans

Formidable and often seemingly insurmountable conceptual, technical, and methodological challenges hamper the measurement of oxidative stress in humans. For instance, fraught and flawed methods, such as the thiobarbituric acid reactive substances assay kits for lipid peroxidation, rate-limit progress. To advance translational redox research, we present ten comprehensive "cheat codes" for measuring oxidative stress in humans. The cheat codes include analytical approaches to assess reactive oxygen species, antioxidants, oxidative damage, and redox regulation. They provide essential conceptual, technical, and methodological information inclusive of curated "do" and "don't" guidelines. Given the biochemical complexity of oxidative stress, we present a research question-grounded decision tree guide for selecting the most appropriate cheat code(s) to implement in a prospective human experiment. Worked examples demonstrate the benefits of the decision tree-based cheat code selection tool. The ten cheat codes define an invaluable resource for measuring oxidative stress in humans.

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.

Mechanistic elucidation of ferroptosis and ferritinophagy: implications for advancing our understanding of arthritis

In recent years, the emerging phenomenon of ferroptosis has garnered significant attention as a distinctive mode of programmed cell death. Distinguished by its reliance on iron and dependence on reactive oxygen species (ROS), ferroptosis has emerged as a subject of extensive investigation. Mechanistically, this intricate process involves perturbations in iron homeostasis, dampening of system Xc-activity, morphological dynamics within mitochondria, and the onset of lipid peroxidation. Additionally, the concomitant phenomenon of ferritinophagy, the autophagic degradation of ferritin, assumes a pivotal role by facilitating the liberation of iron ions from ferritin, thereby advancing the progression of ferroptosis. This discussion thoroughly examines the detailed cell structures and basic processes behind ferroptosis and ferritinophagy. Moreover, it scrutinizes the intricate web of regulators that orchestrate these processes and examines their intricate interplay within the context of joint disorders. Against the backdrop of an annual increase in cases of osteoarthritis, rheumatoid arthritis, and gout, these narrative sheds light on the intriguing crossroads of pathophysiology by dissecting the intricate interrelationships between joint diseases, ferroptosis, and ferritinophagy. The newfound insights contribute fresh perspectives and promising therapeutic avenues, potentially revolutionizing the landscape of joint disease management.

A guide to ferroptosis, the biological rust of cellular membranes

Unprotected iron can rust due to oxygen exposure. Similarly, in our body, oxidative stress can kill cells in an iron-dependent manner, which can give rise to devastating diseases. This type of cell death is referred to as ferroptosis. Generally, ferroptosis is defined as an iron-catalyzed form of regulated necrosis that occurs through excessive peroxidation of polyunsaturated fatty acids within cellular membranes. This review summarizes how ferroptosis is executed by a rather primitive biochemical process, under tight regulation of lipid, iron, and redox metabolic processes. An overview is given of major classes of ferroptosis inducers and inhibitors, and how to detect ferroptosis. Finally, its detrimental role in disease is briefly discussed.

Current Progress of Ferroptosis Study in Hepatocellular Carcinoma

Ferroptosis, an emerging type of programmed cell death, is initiated by iron-dependent and excessive ROS-mediated lipid peroxidation, which eventually leads to plasma membrane rupture and cell death. Many canonical signalling pathways and biological processes are involved in ferroptosis. Furthermore, cancer cells are more susceptible to ferroptosis due to the high load of ROS and unique metabolic characteristics, including iron requirements. Recent investigations have revealed that ferroptosis plays a crucial role in the progression of tumours, especially HCC. Specifically, the induction of ferroptosis can not only inhibit the growth of hepatoma cells, thereby reversing tumorigenesis, but also improves the efficacy of immunotherapy and enhances the antitumour immune response. Therefore, triggering ferroptosis has become a new therapeutic strategy for cancer therapy. In this review, we summarize the characteristics of ferroptosis based on its underlying mechanism and role in HCC and provide possible therapeutic applications.

Pharmacologic Inhibition of Ferroptosis Attenuates Experimental Abdominal Aortic Aneurysm Formation

The pathogenesis of abdominal aortic aneurysm (AAA) formation involves vascular inflammation, thrombosis formation and programmed cell death leading to aortic remodeling. Recent studies have suggested that ferroptosis, an excessive iron-mediated cell death, can regulate cardiovascular diseases, including AAAs. However, the role of ferroptosis in immune cells, like macrophages, and ferroptosis-related genes in AAA formation remains to be deciphered. Single cell-RNA sequencing of human aortic tissue from AAA patients demonstrates significant differences in ferroptosis-related genes compared to control aortic tissue. Using two established murine models of AAA and aortic rupture in C57BL/6 (WT) mice, we observed that treatment with liproxstatin-1, a specific ferroptosis inhibitor, significantly attenuated aortic diameter, pro-inflammatory cytokine production, immune cell infiltration (neutrophils and macrophages), increased smooth muscle cell α-actin expression and elastic fiber disruption compared to mice treated with inactivated elastase in both pre-treatment and treatment after a small AAA had already formed. Lipidomic analysis using mass spectrometry shows a significant increase in ceramides and a decrease in intact lipid species levels in murine tissue compared to controls in the chronic AAA model on day 28. Mechanistically, in vitro studies demonstrate that liproxstatin-1 treatment of macrophages mitigated the crosstalk with aortic smooth muscle cells (SMCs) by downregulating MMP2 secretion. Taken together, this study demonstrates that pharmacological inhibition by liproxstatin-1 mitigates macrophage-dependent ferroptosis contributing to inhibition of aortic inflammation and remodeling during AAA formation.

Ferroptosis resistance in cancer cells: nanoparticles for combination therapy as a solution

Ferroptosis is a form of regulated cell death (RCD) characterized by iron-dependent lipid peroxidation. Ferroptosis is currently proposed as one of the most promising means of combating tumor resistance. Nevertheless, the problem of ferroptosis resistance in certain cancer cells has been identified. This review first, investigates the mechanisms of ferroptosis induction in cancer cells. Next, the problem of cancer cell resistance to ferroptosis, as well as the underlying mechanisms is discussed. Recently discovered ferroptosis-suppressing biomarkers have been described. The various types of nanoparticles that can induce ferroptosis are also discussed. Given the ability of nanoparticles to combine multiple agents, this review proposes nanoparticle-based ferroptosis cell death as a viable method of circumventing this resistance. This review suggests combining ferroptosis with other forms of cell death, such as apoptosis, cuproptosis and autophagy. It also suggests combining ferroptosis with immunotherapy.

Recent Advances in the Inhibition of Membrane Lipid Peroxidation by Food-Borne Plant Polyphenols via the Nrf2/GPx4 Pathway

Lipid peroxidation (LP) leads to changes in the fluidity and permeability of cell membranes, affecting normal cellular function and potentially triggering apoptosis or necrosis. This process is closely correlated with the onset of many diseases. Evidence suggests that the phenolic hydroxyl groups in food-borne plant polyphenols (FPPs) make them effective antioxidants capable of preventing diseases triggered by cell membrane LP. Proper dietary intake of FPPs can attenuate cellular oxidative stress, especially damage to cell membrane phospholipids, by activating the Nrf2/GPx4 pathway. Nuclear factor E2-related factor 2 (Nrf2) is an oxidative stress antagonist. The signaling pathway regulated by Nrf2 is a defense transduction pathway of the organism against external stimuli such as reactive oxygen species and exogenous chemicals. Glutathione peroxidase 4 (GPx4), under the regulation of Nrf2, is the only enzyme that reduces cell membrane lipid peroxides with specificity, thus playing a pivotal role in regulating cellular ferroptosis and counteracting oxidative stress. This study explored the Nrf2/GPx4 pathway mechanism, antioxidant activity of FPPs, and mechanism of LP. It also highlighted the bioprotective properties of FPPs against LP and its associated mechanisms, including (i) activation of the Nrf2/GPx4 pathway, with GPx4 potentially serving as a central target protein, (ii) regulation of antioxidant enzyme activities, leading to a reduction in the production of ROS and other peroxides, and (iii) antioxidant effects on LP and downstream phospholipid structure. In conclusion, FPPs play a crucial role as natural antioxidants in preventing LP. However, further in-depth analysis of FPPs coregulation of multiple signaling pathways is required, and the combined effects of these mechanisms need further evaluation in experimental models. Human trials could provide valuable insights into new directions for research and application.

Mitigating phospholipid peroxidation of macrophages in stress-induced tumor microenvironment by natural ALOX15/PEBP1 complex inhibitors

BACKGROUND

The intricate interactions between chronic psychological stress and susceptibility to breast cancer have been recognized, yet the underlying mechanisms remain unexplored. Danzhi Xiaoyao Powder (DZXY), a traditional Chinese medicine (TCM) formula, has found clinical utility in the treatment of breast cancer. Macrophages, as the predominant immune cell population within the tumor microenvironment (TME), play a pivotal role in orchestrating tumor immunosurveillance. Emerging evidence suggests that lipid oxidation accumulation in TME macrophages, plays a critical role in breast cancer development and progression. However, a comprehensive understanding of the pharmacological mechanisms and active components of DZXY related to its clinical application in the treatment of stress-aggravated breast cancer remains elusive.

PURPOSE

This study sought to explore the plausible regulatory mechanisms and identify the key active components of DZXY contributing to its therapeutic efficacy in the context of breast cancer.

METHODS

Initially, we conducted an investigation into the relationship between the phagocytic capacity of macrophages damaged by psychological stress and phospholipid peroxidation using flow cytometry and LC-MS/MS-based phospholipomics. Subsequently, we evaluated the therapeutic efficacy of DZXY based on the results of the tumor size, tumor weight, the phospholipid peroxidation pathway and phagocytosis of macrophage. Additionally, the target-mediated characterization strategy based on binding of arachidonate 15-lipoxygenase (ALOX15) to phosphatidylethanolamine-binding protein-1 (PEBP1), including molecular docking analysis, microscale thermophoresis (MST) assay, co-immunoprecipitation analysis and activity verification, has been further implemented to reveal the key bio-active components in DZXY. Finally, we evaluated the therapeutic efficacy of isochlorogenic acid C (ICAC) based on the results of tumor size, tumor weight, the phospholipid peroxidation pathway, and macrophage phagocytosis in vivo.

RESULTS

The present study demonstrated that phospholipid peroxides, as determined by LC-MS/MS-based phospholipidomics, triggered in macrophages, which in turn compromised their capacity to eliminate tumor cells through phagocytosis. Furthermore, we elucidate the mechanism behind stress-induced PEBP1 to form a complex with ALOX15, thereby mediating membrane phospholipid peroxidation in macrophages. DZXY, demonstrates potent anti-breast cancer therapeutic effects by disrupting the ALOX15/PEBP1 interaction and inhibiting phospholipid peroxidation, ultimately enhancing macrophages' phagocytic capability towards tumor cells. Notably, ICAC emerged as a promising active component in DZXY, which can inhibit the ALOX15/PEBP1 interaction, thereby mitigating phospholipid peroxidation in macrophages.

CONCLUSION

Collectively, our findings elucidate stress increases the susceptibility of breast cancer by driving lipid peroxidation of macrophages and suggest the ALOX15/PEBP1 complex as a promising intervention target for DZXY.

Cell Membrane-Targeting Type I/II Photodynamic Therapy Combination with FSP1 Inhibition for Ferroptosis-Enhanced Photodynamic Immunotherapy

An imbalance in reactive oxygen species (ROS) levels in tumor cells can result in the accumulation of lipid peroxide (LPO) which can induce ferroptosis. Moreover, elevated ROS levels in tumors present a chance to develop ROS-based cancer therapeutics including photodynamic therapy (PDT) and ferroptosis. However, their anticancer efficacies are compromised by insufficient oxygen levels and inherent cellular ROS regulatory mechanism. Herein, a cell membrane-targeting photosensitizer, TBzT-CNQi, which can generate 1O2, •OH, and O2 •- via type I/II process to induce a high level of LPO for potent ferroptosis and photodynamic therapy is developed. The FSP1 inhibitor (iFSP1) is incorporated with TBzT-CNQi to downregulate FSP1 expression, lower the intracellular CoQ10 content, induce a high level of LPO, and activate initial tumor immunogenic ferroptosis. In vitro and in vivo experiments demonstrate that the cell membrane-targeting type I/II PDT combination with FSP1 inhibition can evoke strong ICD and activate the immune response, which subsequently promotes the invasion of CD8+ T cells infiltration, facilitates the dendritic cell maturation, and decreases the tumor infiltration of tumor-associated macrophages. The study indicates that the combination of cell membrane-targeting type I/II PDT and FSP1 inhibition holds promise as a potential strategy for ferroptosis-enhanced photodynamic immunotherapy of hypoxia tumors.

Induction of Apoptosis with Silver Nanoparticles Obtained Using Thermophilic Bacteria

Yeasts resistant to antifungals have become an increasing risk to human health. One of the best antimicrobial properties is reported to be present in silver nanoparticles (AgNPs); however, little is known about the antimicrobial potential of AgNPs produced using thermophilic bacteria. How AgNPs cause cell death is different depending on the type of the cell, and the mode of death induced is cell-type specific. Apoptosis, one of the types of regulated cell death, can be extremely useful in the fight against infection because surrounding cells that have phagocytic activity can efficiently absorb the apoptotic bodies formed during apoptosis. In the course of this work, for the first time, comprehensive antifungal studies of AgNPs were performed using thermophilic Geobacillus spp. bacteria against Candida guilliermondii, also with the addition of the model yeast Saccharomyces cerevisiae. The determined minimal inhibitory concentrations (MICs) were 10 μg/mL against C. guilliermondii and 50 μg/mL against S. cerevisiae for Geobacillus sp. strain 25 AgNPs, and for Geobacillus sp. 612 the MICs were 5 μg/mL and 25 μg/mL, respectively. It was shown for the first time that the exposure of the yeast cells leads to caspase activation in both S. cerevisiae and C. guilliermondii after exposure to Geobacillus spp. AgNPs. Also, a statistically significant change in the number of cells with permeable membranes was detected. Moreover, it was shown that the antimicrobial effect of the AgNPs is related to ROS generation and lipid peroxidation in C. guilliermondii yeast.

Ferroptosis inhibitors: past, present and future

Ferroptosis is a non-apoptotic mode of programmed cell death characterized by iron dependence and lipid peroxidation. Since the ferroptosis was proposed, researchers have revealed the mechanisms of its formation and continue to explore effective inhibitors of ferroptosis in disease. Recent studies have shown a correlation between ferroptosis and the pathological mechanisms of neurodegenerative diseases, as well as diseases involving tissue or organ damage. Acting on ferroptosis-related targets may provide new strategies for the treatment of ferroptosis-mediated diseases. This article specifically describes the metabolic pathways of ferroptosis and summarizes the reported mechanisms of action of natural and synthetic small molecule inhibitors of ferroptosis and their efficacy in disease. The paper also describes ferroptosis treatments such as gene therapy, cell therapy, and nanotechnology, and summarises the challenges encountered in the clinical translation of ferroptosis inhibitors. Finally, the relationship between ferroptosis and other modes of cell death is discussed, hopefully paving the way for future drug design and discovery.

The emerging role of regulated cell death in ischemia and reperfusion-induced acute kidney injury: current evidence and future perspectives

Renal ischemia‒reperfusion injury (IRI) is one of the main causes of acute kidney injury (AKI), which is a potentially life-threatening condition with a high mortality rate. IRI is a complex process involving multiple underlying mechanisms and pathways of cell injury and dysfunction. Additionally, various types of cell death have been linked to IRI, including necroptosis, apoptosis, pyroptosis, and ferroptosis. These processes operate differently and to varying degrees in different patients, but each plays a role in the various pathological conditions of AKI. Advances in understanding the underlying pathophysiology will lead to the development of new therapeutic approaches that hold promise for improving outcomes for patients with AKI. This review provides an overview of the recent research on the molecular mechanisms and pathways underlying IRI-AKI, with a focus on regulated cell death (RCD) forms such as necroptosis, pyroptosis, and ferroptosis. Overall, targeting RCD shows promise as a potential approach to treating IRI-AKI.

Unresolved questions regarding cellular cysteine sources and their possible relationships to ferroptosis

Cysteine is required for synthesis of glutathione (GSH), coenzyme A, other sulfur-containing metabolites, and most proteins. In most cells, cysteine comes from extracellular disulfide sources including cystine, glutathione-disulfide, and peptides. The thioredoxin reductase-1 (TrxR1)- or glutathione-disulfide reductase (GSR)-driven enzymatic systems can fuel cystine reduction via thioredoxins, glutaredoxins, or other thioredoxin-fold proteins. Free cystine enters cells thorough the cystine-glutamate antiporter, xCT, but systemically, plasma glutathione-disulfide might predominate as a cystine source. Erastin, inhibiting both xCT and voltage-dependent anion channels, induces ferroptotic cell death, so named because this type of cell death is antagonized by iron-chelators. Many cancer cells seem to be predisposed to ferroptosis, which has been proposed as a targetable cancer liability. Ferroptosis is associated with lipid peroxidation and loss of either glutathione peroxidase-4 (GPX4) or ferroptosis suppressor protein-1 (FSP1), which each prevent accumulation of lipid peroxides. It has been suggested that an xCT inhibition-induced cellular cysteine-deficiency lowers GSH levels, starving GPX4 for reducing power and allowing membrane lipid peroxides to accumulate, thereby causing ferroptosis. Aspects of ferroptosis are however not fully understood and need to be further scrutinized, for example that neither disruption of GSH synthesis, loss of GSH, nor disruption of glutathione disulfide reductase (GSR), triggers ferroptosis in animal models. Here we reevaluate the relationships between Erastin, xCT, GPX4, cellular cysteine and GSH, RSL3 or ML162, and ferroptosis. We conclude that, whereas both Cys and ferroptosis are potential liabilities in cancer, their relationship to each other remains insufficiently understood.