Aims: Non-enzymatic autoxidation of polyunsaturated fatty acids (PUFAs), generating numerous toxic by-products implicated in neurodegeneration, aging, and other pathologies, is a key process in ferroptosis. Lipid peroxidation (LPO) can be inhibited by deuterated polyunsaturated fatty acids (D-PUFA), as the rate-limiting step of abstraction of bis-allylic hydrogen atoms is slowed down by replacing the bis-allylic hydrogens with deuteriums. Here, we aimed to assess the protective effect of monounsaturated fatty acids (MUFA), which do not undergo LPO, as compared to that of various D-PUFAs, in a liposomal model of LPO.

Methods: To detect LPO induced by ferrous ions in liposomes, we used the LPO fluorescent probe C11-Bodipy (581/591), in addition to measuring conjugated diene and malondialdehyde accumulation.

Results: By applying the C11-Bodipy (581/591) probe, we found that both 1-palmitoyl-2-oleoyl-phosphatidylcholine (POPC) and 1-stearoyl-2-(11,11-d₂-linoleoyl)-phosphatidylcholine (D2-Lin-PC) protect non-deuterated 1-stearoyl-2-linoleoyl-sn-glycero-3-phosphocholine (H-Lin-PC) liposomes from LPO. Similarly, both POPC and 1-stearoyl-2-(11,11,14,14-D4-linolenyl)-phosphatidylcholine (D4-Lnn-PC) protect 1-stearoyl-2-linolenyl-phosphatidylcholine (H-Lnn-PC), and so does 1-stearoyl-2-(6,6,9,9,12,12,15,15,18,18-d10-docosahexaenoyl)-sn-glycero-3-phosphatidylcholine (D10-DHA-PC). The conjugated diene and malondialdehyde probes also showed similar protective effects of POPC and D-PUFA on LPO in H-Lnn-PC.

Conclusion: Obviously, the presence of non-oxidizable lipids, such as POPC, similar to the deuterated lipids D2-Lin-PC, D4-Lnn-PC, and D10-DHA-PC, leads to a sharp decrease in the length of lateral propagation of chain reactions in lipid membranes, but they do not participate in LPO themselves.

Ferroptosis is a regulated form of cell death driven by iron-dependent lipid peroxidation. Recent evidence indicates that ferroptosis is a critical player associated with cell death and inflammatory processes in neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, as well as in chronic inflammation. In addition, during aging, the expression and activity of various proteins and cellular processes associated with the ferroptotic pathway, such as lipid peroxidation, have been shown to be altered. In this review, we introduce the concept of xenoferroptosis, a process in which ferroptotic signalling is amplified through the combined action of distinct challenges: one involving sub-threshold ferroptosis-related mechanisms, and another involving sub-toxic levels of exogenous or endogenous stressors. Exogenous challenges, such as air pollutants, pesticides, and micro- or nanoplastics, can disrupt redox balance through increased reactive oxygen species production, and impaired antioxidant defences. Endogenous triggers could include misfolded, aggregated proteins, such as amyloid-beta, hyperphosphorylated tau, and alpha-synuclein, which sensitize cells by promoting redox imbalance and mitochondrial dysfunction. While each individual stressor, either endogenous/exogenous or ferroptotic-associated process, may be sublethal, their convergence would initiate a synergistic cascade that accelerates cell death. We propose that xenoferroptosis represents a distinct pathogenic axis at the intersection of molecular pathology and environmental exposure, offering new perspectives for therapeutic interventions that target its dual-trigger mechanisms.

Ferroptosis, an iron-dependent form of regulated cell death (RCD) driven by lipid peroxidation, has been extensively studied since its conceptualization in 2012 and has been suggested as a therapeutic target in many cancers and degenerative diseases. However, three fundamental questions remain unanswered about ferroptosis. First, the mechanisms by which cells execute death during ferroptosis remain elusive: The key role of lipid peroxides in triggering ferroptosis is established, but how this results in the death of a cell remains unclear. Second, the physiological role of ferroptosis throughout the human life cycle is unclear; currently, there is evidence for ferroptosis in early development, immunity, aging, and tumor suppression, but not in many other aspects of physiology. Third, and finally, the intersection between ferroptosis and other RCD modalities, such as apoptosis, necroptosis, pyroptosis, and autophagic cell death, is necessary for understanding how ferroptosis integrates into networks controlling cellular fate. Addressing these gaps in knowledge is essential for building a comprehensive understanding of this mode of cell death, as well as translating ferroptosis knowledge into effective therapeutics.

Osteoarthritis (OA) is increasingly regarded as a whole-organ disease that includes different subsets of joint pathological conditions with variable genetic, biochemical and clinical characteristics. The pathogenesis of OA is perplexing, and disease-modifying drugs are still lacking. Glutathione peroxidase 4 (GPX4), recently best known as the key regulator of ferroptosis implicated in many diseases, including OA, actually has long been identified and reportedly possesses multiple significant biological functions. However, the relationship between GPX4 and OA remains to be elucidated. In this review, we first summarize the current knowledge of GPX4 as a selenoenzyme and the regulation of its expression. Then we scrutinize various possible patterns of involvement of GPX4 in OA. Finally, we also underscore the potential implications and prospects of GPX4-based therapeutic regimens for OA.

Ferroptosis is, in many ways, the odd one out among cell death modalities. It does not, at least as far as we know, require an activating signal. Instead, it represents a default cellular fate that is continuously repressed by a multilayered network of surveillance systems. At its core, ferroptosis is driven by the unchecked peroxidation of polyunsaturated phospholipids (PUFA-PLs), a vulnerability shaped by lipid bilayer composition. Glutathione peroxidase 4 (GPX4) is a central defense enzyme that reduces lipid hydroperoxides to their corresponding alcohols using glutathione as a cofactor. This is complemented by ferroptosis suppressor protein-1 (FSP1)-mediated regeneration of coenzyme Q₁₀ or vitamin K at the plasma membrane and reinforced by dietary or endogenous radical-trapping antioxidants, such as vitamin E, squalene, and 7-dehydrocholesterol. Still, ferroptosis sensitivity is not just a function of antioxidant failure but also a direct consequence of the architecture of the membrane itself: the abundance of PUFA-PLs, shaped by acyl-CoA synthetases like ACSL4 and others; the relative scarcity or abundance of monounsaturated fatty acids, which confer resistance; the regulation of membrane repair and remodeling enzymes; and the delicate balance of redox-active iron within organelles such as lysosomes. Together, these elements converge to determine whether ferroptosis remains a manageable threat or becomes lethal. Despite growing mechanistic insights, fundamental riddles endure: Why does ferroptosis exist at all? What is the precise role of iron: catalyst, signal, or inherent peril? Where, within the cell or organism, does ferroptosis ignite? Can we safely harness this pathway for clinical benefit? And ultimately, is ferroptosis truly a form of regulated cell death, or the mere emergence of a primordial biochemical vulnerability? Inspired by Douglas Green’s iconic riddle framework, this review distils five unresolved questions that may define the coming decade of ferroptosis research. Rather than solving them, we aim to refine their silhouettes at the intersection of lipid (bio)chemistry, evolutionary biology, and translational opportunity.

Iron occupies a paradoxical position in biology: indispensable for life through enabling electron transport in metabolism, yet equally capable of driving cellular death. This is exemplified when ferroptosis was defined in 2012 by Dixon and Stockwell (built on parallel work by Marcus Conrad) as a distinct form of regulated cell death. Crucially, ferroptosis is not simply cell death caused by iron poisoning (i.e., iron overload); rather, the ‘dependency of iron’ is evidenced by specific iron chelators that inhibit the induction of death by agents that disrupt cellular redox control (e.g. erastin, which depletes cellular glutathione, and RSL3, which inhibits GPX4 activity, and others). Still, the etymological emphasis on iron does not fully capture the complexity of ferroptosis, which involves a network of potentially lethal metabolic processes encompassing lipids, thiols, and reactive oxygen species. Adding to this tension, recent negative clinical trials of iron chelators in degenerative diseases where ferroptosis has been implicated have tempered enthusiasm for iron-focused strategies and prompted a re-evaluation of iron’s true role in these diseases, and by extension, ferroptosis. In this perspective, we examine the evolving understanding of the ferrum in ferroptosis, its place within the broader metabolic landscape, and its role in neurodegenerative diseases.

Accurate measurement of cysteine and related thiol-containing metabolites is essential for understanding cellular redox regulation. However, the intrinsic reactivity and instability of cysteine present substantial analytical challenges. This review summarizes the biochemical context of cysteine and glutathione metabolism, emphasizing their dynamic redox equilibria and physiological relevance. We critically examine existing analytical approaches, including mass spectrometry-based, enzyme-coupled, and colorimetric methods, and discuss their respective strengths and limitations. Particular attention is given to sample preparation, derivatization strategies, and reagent selection, as these steps are crucial for preserving native thiol-disulfide status. Among various alkylating agents, N-ethylmaleimide is identified as the most reliable for thiol stabilization in liquid chromatography–mass spectrometry (LC-MS) workflows, while specific reagents such as monobromobimane or β-(4-hydroxyphenyl)ethyl iodoacetamide (HPE-IAM) are required for persulfide and polysulfide detection. The review also highlights the pitfalls of using indirect surrogates—such as glutathione or cystathionine levels—to infer cysteine availability, which can lead to significant misinterpretation of metabolic states. We conclude that direct LC-MS-based quantification of cysteine and glutathione, combined with careful derivatization and sample handling, remains the most reliable and accurate approach currently available for the assessment of thiol metabolism and redox homeostasis.

Ferroptosis, a regulated form of cell death driven by iron-dependent lipid peroxidation, has emerged as a crucial tumor suppressive mechanism and a promising therapeutic target in oncology. This review synthesizes the current understanding of its core molecular machinery, encompassing lipid metabolism, iron homeostasis, and multi-layered cellular defense systems. We highlight the unique metabolic and genetic vulnerabilities that render specific cancer cell types intrinsically susceptible to ferroptosis. Furthermore, we discuss the dynamic propagation of ferroptotic signals within the tumor microenvironment and their complex immunomodulatory effects. Central to this review is a strategic framework for targeting ferroptosis, synthesizing recent advances in the development of specific ferroptosis inducers and evaluating their synergistic potential when combined with chemotherapy, radiotherapy, targeted therapy, and immunotherapy. By integrating mechanistic insight with translational perspectives, this work provides a systematic guide for rationally exploiting ferroptosis in cancer treatment.

Neurons exist at the intersection of two essential yet hazardous metabolic demands: iron-driven bioenergetics and lipid-dependent membrane remodeling. Their reliance on mitochondrial iron for adenosine triphosphate (ATP) generation, combined with the requirement for polyunsaturated fatty acids to sustain synaptic plasticity, creates a biochemical environment primed for ferroptosis. This Perspective examines how the interplay between iron and lipid metabolism defines neuronal vulnerability in neurodegenerative diseases, focusing on apolipoprotein E (ApoE) as a metabolic gatekeeper coordinating those pathways. Beyond its canonical function in lipid transport, ApoE acts as a potent anti-ferroptotic factor by inhibiting ferritinophagy and restraining the release of labile iron, thereby coupling lipid trafficking with iron homeostasis. Dysregulation of this axis in Alzheimer’s disease amplifies lipid peroxidation and compromises antioxidant defenses. Parallel mechanisms are observed in Neurodegeneration with Brain Iron Accumulation disorders, where mutations in lipid-metabolic genes paradoxically lead to brain iron accumulation, underscoring the genetic entanglement of these pathways. Collectively, these findings support a unifying model in which neuronal ferroptosis arises not from isolated iron overload or lipid imbalance, but from the breakdown of a coordinated iron-lipid defense network. We propose that restoring this equilibrium through modulation of ApoE function, preservation of mitochondrial iron utilization, and suppression of lipid peroxidation represents a promising avenue for therapeutic intervention in neurodegenerative disease.

Aims: Endometrial cancer (EC) is often driven by hyperactivation of the PI3K-Akt-mTOR (PAM) pathway due to mutations in PTEN and/or PI3K genes. While mechanistic target of rapamycin complex 1 (mTORC1) inhibitors show limited efficacy as single agents in EC, previous studies suggest that they may sensitize the PAM-mutant cancer cells to ferroptosis, a regulated form of necrosis dependent on iron-catalyzed lipid peroxidation. We investigated whether combining mTORC1 inhibition with ferroptosis induction could overcome resistance mechanisms and improve therapeutic outcomes in EC.

Methods: We evaluated the effect of catalytic, allosteric, and bi-steric mTORC1 inhibition on ferroptosis sensitivity in EC cell lines with different PAM pathway mutational statuses. In vivo efficacy of the combinational treatment was tested in MFE296 xenograft models.

Results: The catalytic and bi-steric mTORC1 inhibitor RMC-6272 sensitized PAM pathway-activated EC cells to ferroptosis induced by GPX4 inhibition, while EC cells without PAM pathway activation were intrinsically sensitive to ferroptosis. Further, mTORC1 inhibition also induced apoptosis in PAM pathway-activated EC cells, indicating a multi-modal cell death response. In vivo, combination treatment with RMC-6272 and the GPX4 inhibitor JKE-1674 significantly suppressed xenograft growth, with evidence of both ferroptosis and apoptosis in tumors.

Conclusion: Our study highlights the therapeutic potential of dual targeting of mTORC1 and ferroptosis to trigger multi-modal cell death in PAM pathway-activated EC, with broader implications for other cancers exhibiting mTORC1 hyperactivation.

Disulfidptosis is a recently identified form of regulated cell death (RCD) triggered by disulfide stress when cystine uptake via solute carrier family 7 member 1 (SLC7A11) overwhelms the cell’s reducing capacity. Unlike apoptosis or other “cell suicide” pathways, disulfidptosis likely represents a “cell sabotage” mechanism, defined by aberrant disulfide bonding and catastrophic actin cytoskeleton collapse. In this Perspective, we examine the paradoxical role of SLC7A11 as both a ferroptosis protector and a disulfidptosis trigger, and the mechanistic hallmarks of disulfidptosis. We highlight emerging therapeutic strategies to target disulfidptosis in cancer, including glucose transporter inhibition, redox-targeting agents, and nanomaterial-based approaches, and consider its dual role in immunity, where it may suppress T cell function yet act as a form of immunogenic cell death. Together, these insights position disulfidptosis as both a conceptual advance in RCD biology and a promising target for cancer therapy that warrants further mechanistic and translational exploration.

Aims: Unique in the broader category of drug-resistant cells, persister cancer cells (PSs) acquire their tolerance to compounds through reversible, chromatin-mediated changes, allowing them to ‘persist’ in the face of cancer therapeutic agents. PSs are implicated in minimal residual disease from which cancer relapse occurs, and given their established sensitivity to ferroptosis, PSs present a critical point through which identification and targeting of drug-resistant cancers may be possible. Ferroptosis sensitivity in drug-resistant cancers may be caused by the attainment of the persister state, or it may merely be correlative with this state and due instead to extended inhibition of oncogenic signaling or the induction of chemotherapy stress. Nonetheless, ferroptosis sensitivity has emerged as a common phenotype across multiple PS and drug-resistant cancer cell types. Identifying biomarkers for and drivers of ferroptosis sensitivity in drug-resistant and PS cells is therefore a high priority.

Methods: We derived PS cells from the lung carcinoma cell line PC9 (PS^PC9), performed transcriptomic analysis, and subsequently lipidomics on the PC9/PS^PC9 system. Additionally, we reverted PS^PC9 cells to the ferroptosis-resistant parental state (PC9^{PS -> PC9}) and assessed the resulting lipid changes. We generated two additional PS-like cell models: PS-like prostate carcinoma (PS^LNCaP) from LNCaP cells and PS-like fibrosarcoma (PS^HT1080) from HT1080 cells, with lipidomics analysis. Finally, we performed a mitochondrial elimination assay and assessed its effect on ferroptosis sensitivity.

Results: We observed enrichment of lipid and sugar metabolism gene expression in PS^PC9; lipidomics revealed enrichment within PS^PC9 for ferroptosis-driving diPUFA phospholipids (diPUFA-PL), as well as polyunsaturated free fatty acids (PUFA FFAs). Upon PS^PC9 reversion to the ferroptosis-resistant parental state (PC9^{PS -> PC9}), this lipid signature reverted. The LNCaP and HT1080 PS-like models individually showed features consistent with PS, including an increased labile-iron pool, reversibility, and enhanced ferroptosis sensitivity, and had lipid features consistent with those in PS^PC9. Finally, mitochondrial elimination partially abrogated ferroptosis sensitivity and altered the PS lipid profile.

Conclusion: In summary, lipidomic changes dependent on the presence of mitochondria are key to the ferroptosis sensitivity of drug-tolerant persister cancer cells.