Ferroptosis inhibition by oleic acid mitigates iron-overload-induced injury

Electroacupuncture Attenuates Cerebral Ischemia-Reperfusion Injury by Inhibiting Ferroptosis via the p53/SLC7A11 Pathway

Acupuncture has demonstrated efficacy in treating post-stroke complications. Electroacupuncture (EA) ameliorates neurological outcomes in cerebral ischemia models, yet its mechanisms remain unclear. This study investigated EA's role in reducing cerebral ischemia-reperfusion injury (CIRI) in a rat model, focusing on ferroptosis. A CIRI model was established via the MCAO/R method. Rats were randomly assigned to five experimental groups: Sham, MCAO/R, MCAO/R + COTI-2, MCAO/R + EA and MCAO/R + COTI-2 + EA. We evaluated neurological function with Zausinger scoring. 2,3,5-Triphenyltetrazolium chloride (TTC) staining assessed infarct size, while haematoxylin-eosin (HE) staining examined neuronal damage. Transmission electron microscopy analysed mitochondrial changes associated with ferroptosis, and Perl staining measured iron levels in neurons. The biomarkers associated with ferroptosis, including glutathione (GSH), reactive oxygen species (ROS) and malondialdehyde (MDA), were measured. The expression of p53, SLC7A11 and GPX4 was assessed by qRT-PCR and Western blot. EA enhanced neurological function, reduced the infarct size, alleviated excessive serum iron accumulation, increased antioxidant markers (GSH, GPX4) and decreased lipid peroxidation levels (ROS, MDA), attenuating lipid peroxidation. Additionally, it reversed mitochondrial morphological changes associated with ferroptosis. qRT-PCR and Western blot analyses revealed that EA downregulated p53 expression while upregulating SLC7A11 and GPX4 expression. In summary, ferroptosis was activated after CIRI, and EA ameliorated neurological deficits in cerebral ischemia models by modulating the p53/SLC7A11 axis to counteract oxidative stress-induced ferroptosis, ultimately providing neuroprotective benefits.

Mechanisms of ferroptosis sensitization and resistance

Ferroptosis is an iron-dependent and oxidative form of non-apoptotic cell death with roles in development, homeostasis, and disease. Ferroptosis sensitivity can vary between cells, often for reasons that are not well understood. In this perspective, we describe the core ferroptosis mechanism and outline how changes in iron, redox, and lipid metabolism can alter ferroptosis sensitivity. We propose the concept of a ferroptosis sensitivity-resistance continuum to describe how different intrinsic and extrinsic factors interact to push cells toward a more ferroptosis-sensitive or ferroptosis-resistant state, with effects on development and diseases such as cancer.

Diet-induced phospholipid remodeling dictates ferroptosis sensitivity and tumorigenesis in the pancreas

High-fat diet (HFD) intake has been linked to an increased risk of pancreatic ductal adenocarcinoma (PDAC), a lethal and therapy-resistant cancer. However, whether and how specific dietary fats drive cancer development remains unresolved. Leveraging an oncogenic Kras -driven mouse model that closely mimics human PDAC progression, we screened a dozen isocaloric HFDs differing solely in fat source and representing the diversity of human fat consumption. Unexpectedly, diets rich in oleic acid - a monounsaturated fatty acid (MUFA) typically associated with good health - markedly enhanced tumorigenesis. Conversely, diets high in polyunsaturated fatty acids (PUFAs) suppressed tumor progression. Relative dietary fatty acid saturation levels (PUFA/MUFA) governed pancreatic membrane phospholipid composition, lipid peroxidation, and ferroptosis sensitivity in mice, concordant with circulating PUFA/MUFA levels being linked to altered PDAC risk in humans. These findings directly implicate dietary unsaturated fatty acids in controlling ferroptosis susceptibility and tumorigenesis, supporting potential "precision nutrition" strategies for PDAC prevention.

PFOS exposure impairs porcine oocyte maturation and embryo development via mitochondria-dependent ferroptosis

Perfluorooctane sulfonate (PFOS) is a widely utilized chemical known for its exceptional environmental stability over extended periods, its significant potential to bioaccumulate in living organisms, and its considerable risks to both health and the environment. Several studies have suggested that PFOS may pose reproductive risks in mammals; however, the exact mechanisms driving these effects are not well understood. In this study, we explored the possible mechanisms by which PFOS toxicity affects the maturation of mammalian oocytes and the embryonic development employing porcine oocytes as a model system. SMART-seq results suggested that PFOS may affect oocyte maturation through mechanisms involving ferroptosis, autophagy, and alterations in membrane structure. Our results suggest that PFOS exposure adversely affects mitochondrial function and structure, thereby influencing peroxisome biogenesis and contributing to oxidative stress. Most importantly, we found that exposure to PFOS significantly elevated Fe2+ levels, an indicator associated with ferroptosis in oocytes. Furthermore, malondialdehyde (MDA) levels in the PFOS group were significantly higher than those in the control group. Additionally, the mRNA expression levels of PCBP1 and PCBP2, which are related to ferroptosis, as well as the expression level of P53, were significantly reduced in the PFOS group. Overall, exposure to PFOS in vitro results in mitochondrial damage in porcine oocytes, which induces lipid peroxidation and subsequently leads to the occurrence of ferroptosis.

Isobavachalcone confers protection against Cryptococcus neoformans-induced ferroptosis in Caenorhabditis elegans via lifespan extension and GSH-GPX-1 axis modulation

The recent designation of Cryptococcus neoformans as a critical-priority fungal pathogen by the World Health Organization highlights the imperative need for novel antifungal agents with distinct mechanisms of action. This study elucidates the novel ferroptotic pathway underlying C. neoformans-induced cell death in Caenorhabditis elegans and investigates the therapeutic potential of isobavachalcone (IBC) through comprehensive evaluation of core biochemical markers: total glutathione (GSH), malondialdehyde, ferrous iron content, and lipid reactive oxygen species (ROS). Integrated transcriptomic analysis via RNA-seq and subsequent RT-qPCR validation revealed critical gene expression patterns associated with antiferroptotic regulation. Our findings demonstrate that C. neoformans infection initiates ferroptosis in C. elegans through iron-dependent lipid peroxidation cascades. Remarkably, IBC administration conferred significant protection against fungal-induced ferroptosis by restoring redox homeostasis-evidenced by elevated GSH levels, attenuated ROS accumulation, and decreased ferrous iron content. Mechanistic investigations identified IBC-mediated upregulation of SKN-1 and GSH biosynthesis genes, coupled with suppression of GPX-1 activity. These coordinated effects disrupted the iron-ROS amplification loop through modulation of the GSH-GPX-1 axis, ultimately extending host lifespan in C. neoformans-challenged models. Our results position IBC as a ferroptosis inhibitor with dual antioxidant and iron-chelating properties, offering a therapeutic strategy against cryptococcal infections through targeting of evolutionary conserved cell death pathways.

Colon-Targeted Hydrogel Microsphere System Encapsulating Oleic Acid-Emodin for Crohn's Disease Treatment via Ferroptosis Inhibition

Crohn's disease (CD) is a relapsing, systemic inflammatory disease that primarily affects the gastrointestinal tract and is often accompanied by extraintestinal manifestations and associated immune disorders. However, current pharmacological treatments for CD encounter several challenges, such as a lack of precise drug targeting and inadequate retention of drugs in the inflamed colon, along with low bioavailability. Herein, we utilized oleic acid (OA) as a solvent to enhance the bioavailability and solubility of emodin. Simultaneously, we encapsulated OA-emodin (OAE) into hydrogel microspheres (HMs) composed of hyaluronic acid (HA) and calcium alginate (CA) to develop a colon-targeted drug delivery system (HM@OAE) for CD therapy. The pH responsiveness of CA enabled HM@OAE to bypass the stomach and specifically target the colon, where it released OAE following oral administration. In addition, in vitro studies demonstrated that HM@OAE significantly reduced the secretion of proinflammatory cytokines, decreased reactive oxygen species levels, and restrained ferroptosis by upregulating GPX4 and SLC7A11 expression while downregulating ACSL4 expression. Furthermore, to confirm these findings in a live organism, an in vivo study was conducted using a dextran sulfate sodium-induced colitis mouse model. This study validated the therapeutic efficacy of HM@OAE, significantly alleviating colonic inflammation and restoring intestinal epithelial integrity. These results suggest that HM@OAE is a promising clinical candidate for CD treatment.

Dietary and nutritional interventions for human diseases: their modulatory effects on ferroptosis

A balanced diet is essential for maintaining human health. Increasing evidence suggests that dietary and nutritional interventions contribute to disease management and are associated with reduced healthcare costs and economic burden. Ferroptosis, a novel type of regulated cell death (RCD) driven by lipid peroxidation, has been shown to be involved in various pathological conditions, including diabetes, ischemia/reperfusion (I/R) injury, inflammation-related diseases, and cancer. Therefore, specifically targeting the uncontrolled ferroptosis process may offer new therapeutic opportunities. Of note, certain interventions, such as small-molecule compounds, natural products, herbal medicines, and non-pharmacological approaches, have been reported to prevent and treat multiple human diseases by reversing the dysregulation of ferroptosis. In this review, we present the key molecular mechanisms that regulate ferroptosis. Importantly, interventions targeting ferroptosis are summarized from the perspective of dietary patterns, food and nutrients. By understanding these advances, innovative ideas can be provided for individualized dietary interventions and treatment strategies.

Anti-Aging Potential of Avocado Oil via Its Antioxidant Effects

Aging is a process characterized by tissue degeneration, increased susceptibility to chronic degenerative diseases, infections, and the appearance of neoplasms, which leads to disability and a reduction in the length and quality of life. This phenomenon is the result of the convergence of multiple processes, including mitochondrial dysfunction, fibrosis, inflammation, dysregulation of cell death processes, and immunosenescence. These processes have as their point of convergence an increase in the production of ROS. Avocado oil (Persea americana Mill.) contains a diverse array of bioactive compounds, including oleic acid, phytosterols, chlorophylls, xanthones, xanthines, and carotenoids. These bioactive compounds have the capacity to modulate the excessive production of ROS, thereby reducing the progression of age-related diseases and extending lifespan in experimental models of aging. In addition, several studies have demonstrated the efficacy of avocado oil in mitigating age-related diseases, including hypertension; insulin resistance; diabetes; non-alcoholic liver disease; and degenerative processes such as hearing loss, cognitive decline, neurodegeneration, and impaired wound healing. In light of these findings, it is hypothesized that avocado oil is a promising agent capable of promoting healthspan in later stages of life owing to its direct antioxidant actions and the activation of pathways that enhance endogenous antioxidant levels.

Integrated bioinformatics and multi-omics to investigate the mechanism of Rhododendron molle Flos-induced hepatotoxicity

ETHNOPHARMACOLOGICAL RELEVANCE

Drug-induced liver injury (DILI) is an important and common adverse drug event. Rhododendron molle Flos (RMF), as one of toxic Traditional Chinese medicines (TCMs), holds a prominent position in clinical practice for treating rheumatoid arthritis. However, the toxicity of RMF limits its safe. Most of the concerns are about its rapid neurotoxicity and cardiotoxicity, with less attention paid to its hepatotoxicity, and the mechanism of which is still unclear.

AIM OF THE STUDY

To reveal the mechanism of RMF-induced hepatotoxicity by bioinformatics and multi-omics.

MATERIALS AND METHODS

Rats were intragastric administered RMF at doses of 0.8 g/kg, 0.4 g/kg, and 0.2 g/kg once daily for 2 weeks. Initially, hepatotoxicity was then evaluated using liver function enzymes, antioxidant enzymes, and histopathology. Subsequently, network toxicology, transcriptomics, and metabolomics were used to identify the genes and metabolites. In addition, molecular docking and Western blot were employed to verify toxic components and key targets.

RESULTS

RMF caused abnormal levels of ALT, γ-GT, TBIL, and TBA in the serum of rats, as well as abnormal levels of MDA, GSH-Px, and SOD in the liver, leading to inflammatory infiltration of liver cells, with a dose-dependent manner. RMF disordered the steroid hormone biosynthesis, pyruvate metabolism, fatty acid biosynthesis, and arachidonic acid metabolism. Six key targets were identified- UGT1A6, CYP2E1, ACOT1, ACSL5, CTH, and PKLR, along with their corresponding metabolites, namely 17β-estradiol, estriol, arachidonic acid, octadecanoic acid, and pyruvic acid. The hepatotoxicity could be attributed to five diterpenoid components, including grayanotoxin-III, rhodojaponin (RJ)-I, RJ-II, RJ-III, and RJ-V.

CONCLUSIONS

This study comprehensively identified the toxic components, upstream targets, and downstream metabolites of RMF-induced liver toxicity, providing a basis for evaluating and monitoring liver function in patients during clinical application.

High-Resolution LC-MS Simultaneous Quantification of Forty-Six Compounds from Jatropha podagrica Fruit Recommends Four Top Antioxidant Contributors as Q-Markers

There has been no chemical analysis of the fruit of medicinal plant Jatropha podagrica until now. The current study aimed to qualitatively and quantitatively analyze the J. podagrica fruit using a high-resolution LC-MS strategy, i.e., library-comparison ultra-high-performance liquid chromatography-Quadrupole-Orbitrap-tandem mass spectrometry. The strategy putatively identified 46 compounds from fresh fruit. During the putative identification, 10 isomers (e.g., (vitexin vs. isovitexin) were completely distinguished from each other. Thereafter, all 46 compounds were simultaneously quantified using authentic standard comparison method. Finally, they were also subjected to the 2,2'-azino bis (3-ethylbenzothiazolin-6-sulfonic acid radical (ABTS+•)-scavenging assay to characterize their relative antioxidant capacities. Their antioxidant capacities were thus multiplied by chemical contents to calculate their antioxidant contribution values, respectively. Corilagin, gallic acid, ellagic acid, and phillygenin exhibited the highest antioxidant contribution percentages and thereby were suggested as the four top antioxidant contributors. The four are recommended to build up a quality-markers (Q-markers) system of J. podagrica fruits. All these findings can help to develop J. podagrica fruits as a potential resource of natural medicine.

Lipid Oxidation at the Crossroads: Oxidative Stress and Neurodegeneration Explored in Caenorhabditis elegans

Lipid metabolism plays a critical role in maintaining cellular integrity, especially within the nervous system, where lipids support neuronal structure, function, and synaptic plasticity. However, this essential metabolic pathway is highly susceptible to oxidative stress, which can lead to lipid peroxidation, a damaging process induced by reactive oxygen species. Lipid peroxidation generates by-products that disrupt many cellular functions, with a strong impact on proteostasis. In this review, we explore the role of lipid oxidation in protein folding and its associated pathological implications, with a particular focus on findings in neurodegeneration from Caenorhabditis elegans studies, an animal model that remains underutilized. Additionally, we highlight the effectiveness of different methodologies applied in this nematode to deepen our understanding of this intricate process. In the nervous system of any animal, including mammals and invertebrates, lipid oxidation can disturb the delicate balance of cellular homeostasis, leading to oxidative stress, the build-up of toxic by-products, and protein misfolding, key factors in neurodegenerative diseases. This disruption contributes to the pathogenesis of neurodegenerative disorders such as Alzheimer's, Parkinson's, or Huntington's disease. The findings from Caenorhabditis elegans studies offer valuable insights into these complex processes and highlight potential avenues for developing targeted therapies to mitigate neurodegenerative disease progression.

In defence of ferroptosis

Rampant phospholipid peroxidation initiated by iron causes ferroptosis unless this is restrained by cellular defences. Ferroptosis is increasingly implicated in a host of diseases, and unlike other cell death programs the physiological initiation of ferroptosis is conceived to occur not by an endogenous executioner, but by the withdrawal of cellular guardians that otherwise constantly oppose ferroptosis induction. Here, we profile key ferroptotic defence strategies including iron regulation, phospholipid modulation and enzymes and metabolite systems: glutathione reductase (GR), Ferroptosis suppressor protein 1 (FSP1), NAD(P)H Quinone Dehydrogenase 1 (NQO1), Dihydrofolate reductase (DHFR), retinal reductases and retinal dehydrogenases (RDH) and thioredoxin reductases (TR). A common thread uniting all key enzymes and metabolites that combat lipid peroxidation during ferroptosis is a dependence on a key cellular reductant, nicotinamide adenine dinucleotide phosphate (NADPH). We will outline how cells control central carbon metabolism to produce NADPH and necessary precursors to defend against ferroptosis. Subsequently we will discuss evidence for ferroptosis and NADPH dysregulation in different disease contexts including glucose-6-phosphate dehydrogenase deficiency, cancer and neurodegeneration. Finally, we discuss several anti-ferroptosis therapeutic strategies spanning the use of radical trapping agents, iron modulation and glutathione dependent redox support and highlight the current landscape of clinical trials focusing on ferroptosis.

Verapamil inhibits ferroptosis in septic acute lung injury by blocking L-type calcium channels

Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), result from pulmonary edema and alveolar-capillary barrier disruption due to inflammation, often triggered by conditions like sepsis. Sepsis-induced ALI (SALI) involves extensive damage to vascular endothelium and alveolar epithelium, leading to respiratory failure. Our study explores ferroptosis, an iron-dependent cell death pathway, and calcium dysregulation in SALI. Elevated cytosolic calcium early in ferroptosis exacerbates lipid peroxidation and cellular damage. We investigated verapamil, a calcium channel blocker, and found it reduces calcium influx, alleviates iron overload, and decreases oxidative stress, protecting against ferroptosis-induced apoptosis in lung cells. These insights suggest targeting ferroptosis pathways, including calcium and iron homeostasis, may offer new therapeutic strategies for SALI, potentially improving outcomes in ALI/ARDS.

ACSL3 is an unfavorable prognostic marker in cholangiocarcinoma patients and confers ferroptosis resistance in cholangiocarcinoma cells

Cholangiocarcinoma (CCA) is a bile duct malignancy. Our previous comprehensive analysis showed that ferroptosis-related genes can stratify CCA patients into low-risk and high-risk groups based on survival time. Here, we explored the role of ferroptosis in CCA by analyzing mRNA expression in CCA patients from public databases. We identified acyl-CoA synthetase long chain family member 3 (ACSL3) as a potential ferroptosis suppressor in high-risk CCA patients. Using a panel of CCA cell lines, we confirmed ACSL3 upregulation in CCA cell lines associated with high-risk CCA, correlating this with resistance to the ferroptosis inducer RSL3. Lipidomic analysis revealed increased monounsaturated fatty acid (MUFA)-containing phospholipids in resistant cell lines. ACSL3 silencing sensitized these cells to RSL3. Resistance to ferroptosis was also dependent on exogenous MUFAs and was enhanced by lipid droplet biogenesis inhibition. These findings highlight ACSL3 as a promising target for therapeutic strategies aimed at overcoming ferroptosis resistance in CCA.

Spatiotemporally Resolved Approach for Profiling Ferroptosis-Associated Metabolic Vulnerabilities in Tumors Using Mass Spectrometry Imaging and Stable Isotope Tracing

Ferroptosis, as an iron-dependent cell death mediated by lipid peroxidation, has sparked great interest in the tumor research community. Targeting ferroptosis has been proven to be a new therapeutic opportunity for inhibiting tumor growth. However, it is challenging to precisely characterize the metabolic pattern of ferroptosis in heterogeneous tumors and further identify ferroptosis-associated metabolic vulnerabilities for tumor treatment. In this work, we developed a spatiotemporally resolved method to image ferroptosis-associated metabolic alterations in 3D tumor spheroids by combining mass spectrometry imaging and stable isotope tracing techniques. The construction of a 3D tumor spheroid model allows for a more accurate simulation of ferroptosis, and the introduction of MALDI-MSI enables in situ screening of abnormal molecules in tumor tissues. Using this method, we showed that the expression proportion of nC═C = 4 polyunsaturated fatty acids, including arachidonic acid (FA-20:4) and adrenic acid (FA-22:4), were upregulated in RSL3-induced 3D tumor ferroptosis models. And the isotope tracing experiment revealed that the absorption of fatty acids and the biosynthesis of polyunsaturated fatty acids were significantly increased during ferroptosis. In addition, we discovered that arachidonic acid and adrenic acid supplementation render tumor cell sensitive to ferroptosis, thereby limiting the growth of tumor cells and the formation of 3D tumor spheroids. Such findings provide significant clues for understanding the metabolic signatures of tumor ferroptosis and raise the possibility to screen potential metabolic vulnerabilities for better tumor treatment in combination with ferroptosis.

Lipid composition differentiates ferroptosis sensitivity between in vitro and in vivo systems

Ferroptosis is a regulated non-apoptotic cell death process characterized by iron-dependent lipid peroxidation. This process has recently emerged as a promising approach for cancer therapy. Peroxidation of polyunsaturated fatty acid-containing phospholipids (PUFA-PLs) is necessary for the execution of ferroptosis. Ferroptosis is normally suppressed by glutathione peroxidase 4 (GPX4), which reduces lipid hydroperoxides to lipid alcohols. Some evidence indicates that GPX4 may be a useful target for drug development, yet factors that govern GPX4 inhibitor sensitivity in vivo are poorly understood. We find that pharmacological and genetic loss of GPX4 function was sufficient to induce ferroptosis in multiple adherent ("2D") cancer cell cultures. However, reducing GPX4 protein levels did not affect tumor xenograft growth when these cells were implanted in mice. Furthermore, sensitivity to GPX4 inhibition was markedly reduced when cells were cultured as spheroids ("3D"). Mechanistically, growth in 3D versus 2D conditions reduced the abundance of PUFA-PLs. 3D culture conditions upregulated the monounsaturated fatty acid (MUFA) biosynthetic gene stearoyl-CoA desaturase (SCD). SCD-derived MUFAs appear to protect against ferroptosis in 3D conditions by displacing PUFAs from phospholipids. Various structurally related long chain MUFAs can inhibit ferroptosis through this PUFA-displacement mechanism. These findings suggest that growth-condition-dependent lipidome remodeling is an important mechanism governing GPX4 inhibitor effects. This resistance mechanism may specifically limit GPX4 inhibitor effectiveness in vivo .

Epidemiological and transcriptome data identify association between iron overload and metabolic dysfunction-associated steatotic liver disease and hepatic fibrosis

The primary objective of this study was to examine the association between iron overload (IO), metabolic dysfunction-associated steatotic liver disease (MASLD), and hepatic fibrosis. We hypothesized that there is a significant association. Data from the NHANES (2017-2020) were analyzed to explore IO's impact on MASLD and hepatic fibrosis in U.S. adults. We assessed serum ferritin, controlled attenuation parameter (CAP), liver stiffness measurement (LSM), and various covariates. Gene expression data were sourced from the FerrDb V2 and GEO databases. Differential gene expression analysis, Protein-Protein Interaction (PPI) Network construction, and Gene Ontology (GO) and KEGG pathway enrichment analyses were performed. The study verified the link between MASLD, hepatic fibrosis, and iron overload hub genes. This study of 5927 participants, averaging 46.78 years of age, revealed significant correlations between serum ferritin and CAP, LSM, after adjusting for covariates. Threshold effect analysis indicated nonlinear associations between serum ferritin and CAP, LSM, with distinct patterns observed by age and gender. Moreover, the area under the ROC curve for serum ferritin with MASLD and hepatic fibrosis was 0.8272 and 0.8376, respectively, demonstrating its performance in assessing these conditions. Additionally, molecular analyses identified potential hub genes associated with iron overload and MASLD, and hepatic fibrosis, revealing the underlying mechanisms. Our study findings reveal an association between iron overload, MASLD, and hepatic fibrosis. Additionally, the hub genes may be implicated in iron overload and subsequently contribute to the progression of MASLD and hepatic fibrosis. These findings support precision nutrition strategies.

The biology of ferroptosis in kidney disease

Ferroptosis is a regulated cell death modality triggered by iron-dependent lipid peroxidation. Ferroptosis plays a causal role in the pathophysiology of various diseases, making it a promising therapeutic target. Unlike all other cell death modalities dependent on distinct signaling cues, ferroptosis occurs when cellular antioxidative defense mechanisms fail to suppress the oxidative destruction of cellular membranes, eventually leading to cell membrane rupture. Physiologically, only two such surveillance systems are known to efficiently prevent the lipid peroxidation chain reaction by reducing (phospho)lipid hydroperoxides to their corresponding alcohols or by reducing radicals in phospholipid bilayers, thus maintaining the integrity of lipid membranes. Mechanistically, these two systems are linked to the reducing capacity of glutathione peroxidase 4 (GPX4) by consuming glutathione (GSH) on one hand and ferroptosis suppressor protein 1 (FSP1, formerly AIFM2) on the other. Notably, the importance of ferroptosis suppression in physiological contexts has been linked to a particular vulnerability of renal tissue. In fact, early work has shown that mice genetically lacking Gpx4 rapidly succumb to acute renal failure with pathohistological features of acute tubular necrosis. Promising research attempting to implicate ferroptosis in various renal disease entities, particularly those with proximal tubular involvement, has generated a wealth of knowledge with widespread potential for clinical translation. Here, we provide a brief overview of the involvement of ferroptosis in nephrology. Our goal is to introduce this expanding field for clinically versed nephrologists in the hope of spurring future efforts to prevent ferroptosis in the pathophysiological processes of the kidney.

Hyperbaric Oxygen Improves Cognitive Impairment Induced by Hypoxia via Upregulating the Expression of Oleic Acid and MBOAT2 of Mice

Cognitive impairment (CI) causes severe impairment of brain function and quality of life of patients, which brings a great burden to society. Cerebral hypoxia is an important factor in the pathogenesis of CI. Hyperbaric oxygen (HBO) therapy may mitigate hypoxia-induced CI, but its efficacy and mechanisms are not fully understood. In this study, a mice model of CI induced by hypoxia environment was established, then behavioral tests, pathological examination, metabolomic and lipidomic analyses, and molecular biology were used to assess the impact of HBO on hypoxia-induced CI. HBO was found to alleviate CI and pathological damage of hypoxia mice. Metabolomic, lipidomic, and molecular biology analyses showed that HBO increased the levels of oleic acid (OA) and membrane-bound O-acyltransferase 2 (MBOAT2), thereby altering the composition of membrane phospholipids (PLs) and reducing hypoxia-induced neuronal ferroptosis (FPT) to interfere with cognitive function in mice. In vitro experiments confirmed that OA and MBOAT2 led to membrane PL remodeling in a mutually dependent manner, affecting cell resistance to hypoxia-FPT. The results emphasized the combined effect value of OA and MBOAT2 in HBO for hypoxia-induced CI, and provided a novel perspective for the treatment of CI by HBO.

Human breast milk-derived phospholipid DOPE ameliorates intestinal injury associated with NEC by inhibiting ferroptosis

Neonatal necrotizing enterocolitis (NEC) is a severe inflammatory bowel disease that commonly affects premature infants. Breastfeeding has been proven to be one of the most effective methods for preventing NEC. However, the specific role of lipids, the second major nutrient category in human breast milk (HBM), in intestinal development remains unclear. Our preliminary lipidomic analysis of the HBM lipidome revealed that dioleoyl phosphatidylethanolamine (DOPE) is not only abundant but also shows high solubility in lipids, endowing it with significant biological utility. Experimental results confirmed that DOPE significantly reduces the mortality of neonatal rats, ameliorates impairment of intestinal barrier function, and alleviates the expression of intestinal inflammatory factors IL-1β and IL-6. Furthermore, DOPE promotes the migration and proliferation of intestinal epithelial cells, thereby enhancing the integrity of the intestinal barrier function in vitro. The progression of NEC is linked with the onset of ferroptosis. Our cellular-level analysis of lipid peroxide and iron ion concentrations revealed that DOPE significantly reduces the indicators of ferroptosis, while also modulating the expression of pivotal ferroptosis-associated factors, including SLC7A11, GPX4, and ACSL4. Hence, this research on DOPE is expected to provide novel insights into the bioactive lipids present in HBM.

Suppression of ferroptosis by vitamin A or radical-trapping antioxidants is essential for neuronal development

The development of functional neurons is a complex orchestration of multiple signaling pathways controlling cell proliferation and differentiation. Because the balance of antioxidants is important for neuronal survival and development, we hypothesized that ferroptosis must be suppressed to gain neurons. We find that removal of antioxidants diminishes neuronal development and laminar organization of cortical organoids, which is fully restored when ferroptosis is inhibited by ferrostatin-1 or when neuronal differentiation occurs in the presence of vitamin A. Furthermore, iron-overload-induced developmental growth defects in C. elegans are ameliorated by vitamin E and A. We determine that all-trans retinoic acid activates the Retinoic Acid Receptor, which orchestrates the expression of anti-ferroptotic genes. In contrast, retinal and retinol show radical-trapping antioxidant activity. Together, our study reveals an unexpected function of vitamin A in coordinating the expression of essential cellular gatekeepers of ferroptosis, and demonstrates that suppression of ferroptosis by radical-trapping antioxidants or by vitamin A is required to obtain mature neurons and proper laminar organization in cortical organoids.

Study on the Extraction of Nervonic Acid from the Oil of Xanthoceras sorbifolium Bunge Seeds

Seven fatty acids were detected by GC-MS in Xanthoceras sorbifolium Bunge seed oil extracted at different temperatures, including Palmitic acid C16:0, Stearic acid C18:0, Oleic acid C18:1, Eicosenoic acid C20:1, Docosenoic acid C22:1, Tetracosenoic acid C24:1, and Linoleic acid C18:2. The highest content of nervonic acid (NA) was found in Xanthoceras sorbifolium Bunge seed oil extracted at 70 °C. Three methods were selected to analyze the extraction rate of nervonic acid in Xanthoceras sorbifolium Bunge seed oil, including urea complexation, low-temperature solvent crystallization, and a combined treatment using these two methods. The final content of nervonic acid obtained was 14.07%, 19.66%, and 40.17%, respectively. The combined treatment method increased the purity of nervonic acid in Xanthoceras sorbifolium Bunge seed oil by 12.62 times. Meanwhile, thermogravimetric behavior analysis of samples extracted using different methods was conducted by thermogravimetric analyzer, which suggested that the thermal stability of the samples extracted by the combined treatment was enhanced. These results can provide a new process parameter and scientific basis for the extraction of NA. At the same time, FTIR and NMR were also used to characterize the combined extraction sample, and the structure of the samples was proved.

Immunometabolism of ferroptosis in the tumor microenvironment

Ferroptosis is an iron-dependent form of cell death that results from excess lipid peroxidation in cellular membranes. Within the last decade, physiological and pathological roles for ferroptosis have been uncovered in autoimmune diseases, inflammatory conditions, infection, and cancer biology. Excitingly, cancer cell metabolism may be targeted to induce death by ferroptosis in cancers that are resistant to other forms of cell death. Ferroptosis sensitivity is regulated by oxidative stress, lipid metabolism, and iron metabolism, which are all influenced by the tumor microenvironment (TME). Whereas some cancer cell types have been shown to adapt to these stressors, it is not clear how immune cells regulate their sensitivities to ferroptosis. In this review, we discuss the mechanisms of ferroptosis sensitivity in different immune cell subsets, how ferroptosis influences which immune cells infiltrate the TME, and how these interactions can determine epithelial-to-mesenchymal transition (EMT) and metastasis. While much focus has been placed on inducing ferroptosis in cancer cells, these are important considerations for how ferroptosis-modulating strategies impact anti-tumor immunity. From this perspective, we also discuss some promising immunotherapies in the field of ferroptosis and the challenges associated with targeting ferroptosis in specific immune cell populations.

Ferrostatin-1 mitigates cellular damage in a ferroptosis-like environment in Caenorhabditis elegans

Although iron (Fe) is the most biologically abundant transition metal, it is highly toxic when it accumulates as Fe2+, forming a labile Fe pool and favoring the Fenton reaction. This oxidative scenario leads to a type of caspase-independent programmed cell death, referred to as ferroptosis, where following processes take place: (i) Fe2+ overload, (ii) glutathione peroxidase 4 inactivation, (iii) lipid peroxidation, and (iv) glutathione depletion. The present study sought to evaluate the consequences of Fe2+ administration on ferroptosis induction in Caenorhabditis elegans. We demonstrated higher mortality, increased lipid peroxidation, reduced glutathione peroxidase activity, and morphological damage in dopaminergic neurons upon Fe2+ overload. Pharmacological intervention at the level of lipid peroxidation with ferrostatin-1 (250 μM) mitigated the damage and returned the biochemical parameters to basal levels, revealing the potential of this therapeutical approach. Finally, to assess the relationship between ferroptosis and dopamine in a Parkinsonian background, we evaluated the UA44 worm strain which overexpresses the alpha-synuclein protein in cherry-labeled dopaminergic neurons. We demonstrated that Fe2+ administration reduced lethality associated with similar alterations in biochemical and dopaminergic morphological parameters in wild-type animals. These experiments provide mechanistic-based evidence on the efficacy of a pharmacological approach to mitigate the physiological, biochemical, and morphological consequences of Fe2+ overload. At the same time, they encourage further research on the impact of the combined effects resulting from the genetic background and dopamine signaling in a Parkinsonian phenotype.

Investigation of the mutual crosstalk between ER stress and PI3K/AKT/mTOR signaling pathway in iron overload-induced liver injury in chicks

Iron is an essential element for the normal functioning of living organisms, but excessive iron deposition can lead to organ damage. This study aims to investigate the interaction between the endoplasmic reticulum stress signaling pathway and the PI3K/AKT/mTOR signaling pathway in liver injury induced by iron overload in chicks. Rspectively, 150 one-day-old broilers were divided into three groups and supplemented with 50 (C), 500 (E1), and 1000 (E2) mg ferrous sulfate monohydrate/kg in the basal diet. Samples were taken after continuous feeding for 14 days. The results showed that iron overload could upregulate the levels of ALT and AST. Histopathological examination revealed bleeding in the central vein of the liver accompanied by inflammatory cell infiltration. Hoechst staining showed that the iron overload group showed significant bright blue fluorescence, and ultrastructural observations showed chromatin condensation as well as mitochondrial swelling and cristae disorganization in the iron overload group. RT-qPCR and Western blot results showed that iron overload upregulated the expression of Bax, Caspase-3, Caspase-9, GRP78, GRP94, P-PERK, ATF4, eIF2α, IRE1, and ATF6, while downregulating the expression of Bcl-2 and the PI3K/AKT/mTOR pathway. XBP-1 splicing experiment showed significant splicing of XBP-1 gene after iron overload. PCA and correlation analysis suggested a potential association between endoplasmic reticulum stress, the PI3K/AKT/mTOR signaling pathway, and liver injury in chicks. In summary, iron overload can induce cell apoptosis and liver injury by affecting endoplasmic reticulum stress and the PI3K/AKT/mTOR signaling pathway.

The Roles of White Adipose Tissue and Liver NADPH in Dietary Restriction-Induced Longevity

Dietary restriction (DR) protocols frequently employ intermittent fasting. Following a period of fasting, meal consumption increases lipogenic gene expression, including that of NADPH-generating enzymes that fuel lipogenesis in white adipose tissue (WAT) through the induction of transcriptional regulators SREBP-1c and CHREBP. SREBP-1c knockout mice, unlike controls, did not show an extended lifespan on the DR diet. WAT cytoplasmic NADPH is generated by both malic enzyme 1 (ME1) and the pentose phosphate pathway (PPP), while liver cytoplasmic NADPH is primarily synthesized by folate cycle enzymes provided one-carbon units through serine catabolism. During the daily fasting period of the DR diet, fatty acids are released from WAT and are transported to peripheral tissues, where they are used for beta-oxidation and for phospholipid and lipid droplet synthesis, where monounsaturated fatty acids (MUFAs) may activate Nrf1 and inhibit ferroptosis to promote longevity. Decreased WAT NADPH from PPP gene knockout stimulated the browning of WAT and protected from a high-fat diet, while high levels of NADPH-generating enzymes in WAT and macrophages are linked to obesity. But oscillations in WAT [NADPH]/[NADP+] from feeding and fasting cycles may play an important role in maintaining metabolic plasticity to drive longevity. Studies measuring the WAT malate/pyruvate as a proxy for the cytoplasmic [NADPH]/[NADP+], as well as studies using fluorescent biosensors expressed in the WAT of animal models to monitor the changes in cytoplasmic [NADPH]/[NADP+], are needed during ad libitum and DR diets to determine the changes that are associated with longevity.

Ferroptosis: principles and significance in health and disease

Ferroptosis, an iron-dependent form of cell death characterized by uncontrolled lipid peroxidation, is governed by molecular networks involving diverse molecules and organelles. Since its recognition as a non-apoptotic cell death pathway in 2012, ferroptosis has emerged as a crucial mechanism in numerous physiological and pathological contexts, leading to significant therapeutic advancements across a wide range of diseases. This review summarizes the fundamental molecular mechanisms and regulatory pathways underlying ferroptosis, including both GPX4-dependent and -independent antioxidant mechanisms. Additionally, we examine the involvement of ferroptosis in various pathological conditions, including cancer, neurodegenerative diseases, sepsis, ischemia-reperfusion injury, autoimmune disorders, and metabolic disorders. Specifically, we explore the role of ferroptosis in response to chemotherapy, radiotherapy, immunotherapy, nanotherapy, and targeted therapy. Furthermore, we discuss pharmacological strategies for modulating ferroptosis and potential biomarkers for monitoring this process. Lastly, we elucidate the interplay between ferroptosis and other forms of regulated cell death. Such insights hold promise for advancing our understanding of ferroptosis in the context of human health and disease.

The cell biology of ferroptosis

Ferroptosis is a non-apoptotic cell death mechanism characterized by iron-dependent membrane lipid peroxidation. Here, we review what is known about the cellular mechanisms mediating the execution and regulation of ferroptosis. We first consider how the accumulation of membrane lipid peroxides leads to the execution of ferroptosis by altering ion transport across the plasma membrane. We then discuss how metabolites and enzymes that are distributed in different compartments and organelles throughout the cell can regulate sensitivity to ferroptosis by impinging upon iron, lipid and redox metabolism. Indeed, metabolic pathways that reside in the mitochondria, endoplasmic reticulum, lipid droplets, peroxisomes and other organelles all contribute to the regulation of ferroptosis sensitivity. We note how the regulation of ferroptosis sensitivity by these different organelles and pathways seems to vary between different cells and death-inducing conditions. We also highlight transcriptional master regulators that integrate the functions of different pathways and organelles to modulate ferroptosis sensitivity globally. Throughout this Review, we highlight open questions and areas in which progress is needed to better understand the cell biology of ferroptosis.

A guide to ferroptosis in cancer

Ferroptosis is a newly identified iron-dependent type of regulated cell death that can also be regarded as death caused by the specific collapse of the lipid antioxidant defence machinery. Ferroptosis has gained increasing attention as a potential therapeutic strategy for therapy-resistant cancer types. However, many ferroptosis-inducing small molecules do not reach the pharmacokinetic requirements for their effective clinical use yet. Nevertheless, their clinical optimization is under development. In this review, we summarize the current understanding of molecular pathways regulating ferroptosis, how cells protect themselves from the induction of ferroptotic cell death, and how a better understanding of cancer cell metabolism can represent vulnerabilities for ferroptosis-based therapies. Lastly, we discuss the context-dependent effect of ferroptosis on various cell types within the tumor microenvironment and address controversies on how tissue ferroptosis might impact systemic cancer immunity in a paracrine manner.

Fatal COVID-19 pulmonary disease involves ferroptosis

SARS-CoV-2 infection causes severe pulmonary manifestations, with poorly understood mechanisms and limited treatment options. Hyperferritinemia and disrupted lung iron homeostasis in COVID-19 patients imply that ferroptosis, an iron-dependent cell death, may occur. Immunostaining and lipidomic analysis in COVID-19 lung autopsies reveal increases in ferroptosis markers, including transferrin receptor 1 and malondialdehyde accumulation in fatal cases. COVID-19 lungs display dysregulation of lipids involved in metabolism and ferroptosis. We find increased ferritin light chain associated with severe COVID-19 lung pathology. Iron overload promotes ferroptosis in both primary cells and cancerous lung epithelial cells. In addition, ferroptosis markers strongly correlate with lung injury severity in a COVID-19 lung disease model using male Syrian hamsters. These results reveal a role for ferroptosis in COVID-19 pulmonary disease; pharmacological ferroptosis inhibition may serve as an adjuvant therapy to prevent lung damage during SARS-CoV-2 infection.

Therapeutic exploitation of ferroptosis

Pathological breakdown of membrane lipids through excessive lipid peroxidation (LPO) was first described in the mid-20th century and is now recognized as a form of regulated cell death, dubbed ferroptosis. Accumulating evidence unveils how metabolic regulation restrains peroxidation of phospholipids within cellular membranes, thereby impeding ferroptosis execution. Unleashing these metabolic breaks is currently therapeutically explored to sensitize cancers to ferroptosis inducing anti-cancer therapies. Reversely, these natural ferroptotic defense mechanisms can fail resulting in pathological conditions or diseases such as ischemia-reperfusion injury, multi-organ dysfunction, stroke, infarction, or neurodegenerative diseases. This minireview outlines current ferroptosis-inducing anti-cancer strategies and highlights the detection as well as the therapeutic targeting of ferroptosis in preclinical experimental settings. Herein, we also briefly summarize observations related to LPO, iron and redox deregulation in patients that might hint towards ferroptosis as a contributing factor.