The calcium-iron connection in ferroptosis-mediated neuronal death

The differential impact of iron on ferroptosis, oxidative stress, and inflammatory reaction in head-kidney macrophages of yellow catfish (Pelteobagrus fulvidraco) with and without ammonia stress

Ammonia toxicity in fish is closely related to ferroptosis, oxidative stress, and inflammatory responses. Iron is an essential trace element that plays a key role in many biological processes for cells and organisms, including ferroptosis, oxidative stress response, and inflammation. This study aimed to investigate the effect of iron on indicators of fish exposed to ammonia, specifically on the three aspects mentioned above. The head kidney macrophages of yellow catfish were randomly assigned to one of four groups: CON (normal control), AM (0.046 mg L-1 total ammonia nitrogen), Fe (20 μg mL-1 FeSO4), and Fe + AM (20 μg mL-1 FeSO4, 0.046 mg L-1 total ammonia nitrogen). The cells were pretreated with FeSO4 for 6 h followed by ammonia for 24 h. The study found that iron supplementation led to an excessive accumulation of iron and ROS in macrophages, but it did not strongly induce ferroptosis, oxidative stress, or inflammatory responses. This was supported by a decrease in T-AOC, and the downregulation of SOD, as well as an increase in GSH levels and the upregulation of TFR1, CAT and Nrf2. Furthermore, the mRNA expression of HIF-1, p53 and the anti-inflammatory M2 macrophage marker Arg-1 were upregulated. The results also showed that iron supplementation increased the progression of some macrophages from early apoptosis to late apoptotic cells. However, the combined treatment of iron and ammonia resulted in a stronger intracellular ferroptosis, oxidative stress, and inflammatory reaction compared to either treatment alone. Additionally, there was a noticeable increase in necrotic cells in the Fe + AM and AM groups. These findings indicate that the biological functions of iron in macrophages of fish may vary inconsistently in the presence or absence of ammonia stress.

Physical Exercise-Induced Activation of NRF2 and BDNF as a Promising Strategy for Ferroptosis Regulation in Parkinson's Disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra. Ferroptosis, an iron-dependent form of regulated cell death, may contribute to the progression of PD owing to an unbalanced brain redox status. Physical exercise is a complementary therapy that can modulate ferroptosis in PD by regulating the redox system through the activation of nuclear factor (erythroid-derived 2)-like 2 (NRF2) and brain-derived neurotrophic factor (BDNF) signaling. However, the precise effects of physical exercise on ferroptosis in PD remain unclear. In this review, we explored how physical exercise influences NRF2 and BDNF signaling and affects ferroptosis in PD. We further investigated relevant publications over the past two decades by searching the PubMed, Web of Science, and Google Scholar databases using keywords related to physical exercise, PD, ferroptosis, and neurotrophic factor antioxidant signaling. This review provides insights into current research gaps and demonstrates the necessity for future research to elucidate the specific mechanisms by which exercise regulates ferroptosis in PD, including the assessment of different exercise protocols and their long-term effects. Ultimately, exploring these aspects may lead to the development of improved exercise interventions for the better management of patients with PD.

CGI1746 targets σ1R to modulate ferroptosis through mitochondria-associated membranes

Ferroptosis is iron-dependent oxidative cell death. Labile iron and polyunsaturated fatty acid (PUFA)-containing lipids are two critical factors for ferroptosis execution. Many processes regulating iron homeostasis and lipid synthesis are critically involved in ferroptosis. However, it remains unclear whether biological processes other than iron homeostasis and lipid synthesis are associated with ferroptosis. Using kinase inhibitor library screening, we discovered a small molecule named CGI1746 that potently blocks ferroptosis. Further studies demonstrate that CGI1746 acts through sigma-1 receptor (σ1R), a chaperone primarily located at mitochondria-associated membranes (MAMs), to inhibit ferroptosis. Suppression of σ1R protects mice from cisplatin-induced acute kidney injury hallmarked by ferroptosis. Mechanistically, CGI1746 treatment or genetic disruption of MAMs leads to defective Ca2+ transfer, mitochondrial reactive oxygen species (ROS) production and PUFA-containing triacylglycerol accumulation. Therefore, we propose a critical role for MAMs in ferroptosis execution.

Nanomedicine-based disulfiram and metal ion co-delivery strategies for cancer treatment

Disulfiram (DSF) is a second-line drug for the clinical treatment of alcoholism and has long been proven to be safe for use in clinical practice. In recent years, researchers have discovered the cancer-killing activity of DSF, which is highly dependent on the presence of metal ions, particularly copper ions. Additionally, free DSF is highly unstable and easily degraded within few minutes in blood circulation. Therefore, an ideal DSF formulation should facilitate the co-delivery of metal ions and safeguard the DSF throughout its biological journey before reaching the targeted site. Extensive research have proved that nanotechnology based formulations can effectively realize this goal by strategic encapsulation therapeutic agents within nanoparticle. To be more specific, this is accomplished through precise delivery, coordinated release of metal ions at the tumor site, thereby amplifying its cytotoxic potential. Beyond traditional co-loading techniques, innovative approaches such as DSF-metal complex and metal nanomaterials, have also demonstrated promising results at the animal model stage. This review aims to elucidate the anticancer mechanism associated with DSF and its reliance on metal ions, as well as to provide a comprehensive overview of recent advances in the arena of nanomedicine based co-delivery strategies for DSF and metal ion in the context of cancer therapy.

Increased Vulnerability to Ferroptosis in FUS-ALS

Ferroptosis, a regulated form of cell death characterized by iron-dependent lipid peroxide accumulation, plays a pivotal role in various pathological conditions, including neurodegenerative diseases. While reasonable evidence for ferroptosis exists, e.g., in Parkinson's disease or Alzheimer's disease, there are only a few reports on amyotrophic lateral sclerosis (ALS), a fast progressive and incurable neurodegenerative disease characterized by progressive motor neuron degeneration. Interestingly, initial studies have suggested that ferroptosis might be significantly involved in ALS. Key features of ferroptosis include oxidative stress, glutathione depletion, and alterations in mitochondrial morphology and function, mediated by proteins such as GPX4, xCT, ACSL4 FSP1, Nrf2, and TfR1. Induction of ferroptosis involves small molecule compounds like erastin and RSL3, which disrupt system Xc- and GPX4 activity, respectively, resulting in lipid peroxidation and cellular demise. Mutations in fused in sarcoma (FUS) are associated with familial ALS. Pathophysiological hallmarks of FUS-ALS involve mitochondrial dysfunction and oxidative damage, implicating ferroptosis as a putative cell-death pathway in motor neuron demise. However, a mechanistic understanding of ferroptosis in ALS, particularly FUS-ALS, remains limited. Here, we investigated the vulnerability to ferroptosis in FUS-ALS cell models, revealing mitochondrial disturbances and increased susceptibility to ferroptosis in cells harboring ALS-causing FUS mutations. This was accompanied by an altered expression of ferroptosis-associated proteins, particularly by a reduction in xCT expression, leading to cellular imbalance in the redox system and increased lipid peroxidation. Iron chelation with deferoxamine, as well as inhibition of the mitochondrial calcium uniporter (MCU), significantly alleviated ferroptotic cell death and lipid peroxidation. These findings suggest a link between ferroptosis and FUS-ALS, offering potential new therapeutic targets.

Ferroptosis mechanisms and regulations in cardiovascular diseases in the past, present, and future

Cardiovascular diseases (CVDs) are the main diseases that endanger human health, and their risk factors contribute to high morbidity and a high rate of hospitalization. Cell death is the most important pathophysiology in CVDs. As one of the cell death mechanisms, ferroptosis is a new form of regulated cell death (RCD) that broadly participates in CVDs (such as myocardial infarction, heart transplantation, atherosclerosis, heart failure, ischaemia/reperfusion (I/R) injury, atrial fibrillation, cardiomyopathy (radiation-induced cardiomyopathy, diabetes cardiomyopathy, sepsis-induced cardiac injury, doxorubicin-induced cardiac injury, iron overload cardiomyopathy, and hypertrophic cardiomyopathy), and pulmonary arterial hypertension), involving in iron regulation, metabolic mechanism and lipid peroxidation. This article reviews recent research on the mechanism and regulation of ferroptosis and its relationship with the occurrence and treatment of CVDs, aiming to provide new ideas and treatment targets for the clinical diagnosis and treatment of CVDs by clarifying the latest progress in CVDs research.

Evaluation of binding mechanism of dietary phytochemical, capsaicin, with human transferrin: targeting neurodegenerative diseases therapeutics

Human transferrin (htf) plays a crucial role in regulating the balance of iron within brain cells; any disruption directly contributes to the development of Neurodegenerative Diseases (NDs) and other related pathologies, especially Alzheimer's Disease (AD). In recent times, a transition towards natural compounds is evident to treat diseases and this shift is mainly attributed to their broad therapeutic potential along with minimal side effects. Capsaicin, a natural compound abundantly found in red and chili peppers, possess neuroprotective potential. The current work targets to decipher the interaction mechanism of capsaicin with htf using experimental and computational approaches. Molecular docking analysis revealed that capsaicin occupies the iron binding pocket of htf, with good binding affinity. Further, the binding mechanism was investigated atomistically using Molecular dynamic (MD) simulation approach. The results revealed no significant alterations in the structure of htf implying the stability of the complex. In silico observations were validated by fluorescence binding assay. Capsaicin binds to htf with a binding constant (K) of 3.99 × 106 M-1, implying the stability of the htf-capsaicin complex. This study lays a platform for potential applications of capsaicin in treatment of NDs in terms of iron homeostasis.

Application of calcium overload-based ion interference therapy in tumor treatment: strategies, outcomes, and prospects

Low selectivity and tumor drug resistance are the main hinderances to conventional radiotherapy and chemotherapy against tumor. Ion interference therapy is an innovative anti-tumor strategy that has been recently reported to induce metabolic disorders and inhibit proliferation of tumor cells by reordering bioactive ions within the tumor cells. Calcium cation (Ca2+) are indispensable for all physiological activities of cells. In particular, calcium overload, characterized by the abnormal intracellular Ca2+ accumulation, causes irreversible cell death. Consequently, calcium overload-based ion interference therapy has the potential to overcome resistance to traditional tumor treatment strategies and holds promise for clinical application. In this review, we 1) Summed up the current strategies employed in this therapy; 2) Described the outcome of tumor cell death resulting from this therapy; 3) Discussed its potential application in synergistic therapy with immunotherapy.

The effects of noise exposure on hippocampal cognition in C57BL/6 mice via transcriptomics

BACKGROUND

Noise is an important environmental stressor in the industrialized world and has received increasing attention in recent years. Although epidemiological research has extensively demonstrated the relationship between noise and cognitive impairment, the specific molecular mechanisms and targets remain to be fully explored and understood.

METHODS

To address this issue, 5-month-old C57BL/6 mice were divided into two groups, with one group exposed to white noise at 98 dB. The effects of noise on cognition in mice were investigated through molecular biology and behavioral experiments. Subsequently, transcriptomic sequencing of the hippocampus in both groups of mice was performed and enrichment analysis of differentially expressed genes (DEGs) was conducted using KEGG and GO databases. Furthermore, LASSO analysis was used to further narrow down the relevant DEGs, followed by enrichment analysis of these genes using KEGG and GO databases. The DEGs were further validated by rt-qPCR.

RESULTS

Following noise exposure, the hippocampus levels of inflammation-related factors increased, the phosphorylation of Tau protein increased, the postsynaptic density protein decreased, the number of Nissl bodies decreased, and cell shrinkage in the hippocampus increased. Moreover, the behavioral experiments manifest characteristics indicative of a decline in cognitive.A total of 472 DEGs were identified through transcriptomic analysis, and seven relevant genes were screened by the LASSO algorithm, which were further validated by PCR to confirm their consistency with the omics results.

CONCLUSION

In conclusion, noise exposure affects cognitive function in mice through multiple pathways, and the omics results provide new evidence for the cognitive impairment induced by noise exposure.

Mitochondria-related signaling pathways involved in breast cancer regulate ferroptosis

Ferroptosis is a novel form of regulated cell death characterized by iron-dependent excessive lipid peroxidation. The core organelle involved in ferroptosis is mitochondria. Mitochondria undergoing ferroptosis are distinct from normal mitochondria in terms of morphology, biochemistry, gene expression, and energy metabolism. An increasing number of studies have shown that mitochondria and their associated metabolic pathways mediate ferroptosis in the development and progression of breast cancer. In this review, we discuss the relevant research about ferroptosis in breast cancer and provide a comprehensive summary of mitochondrial regulation in ferroptosis from the perspective of lipid metabolism, oxidative phosphorylation, ion metabolism, glycometabolism, and nucleotide metabolism. We also summarize the application of mitochondrial metabolism-related pathways as ferroptosis treatment targets. Here we provide new insights into the relationship between mitochondria, ferroptosis, and breast cancer treatment.

Ferroptosis-related genes are considered as potential targets for CPAP treatment of obstructive sleep apnea

Obstructive sleep apnea (OSA) is a common syndrome characterized by upper airway dysfunction during sleep. Continuous positive airway pressure (CPAP) is the most frequently utilized non-surgical treatment for OSA. Ferroptosis play a crucial role in the physiological diseases caused by chronic intermittent hypoxia, but its involvement in the development of OSA and the exact mechanisms have incompletely elucidated. GSE75097 microarray dataset was used to identify differentially expressed genes between OSA patients and CPAP-treated OSA patients. Subsequently, Gene Ontology (GO) annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, STRING database, and FerrDb database were conducted to analyze the biological functions of differentially expressed genes and screen ferroptosis-related genes. Finally, GSE135917 dataset employed for validation. There were 1,540 differentially expressed genes between OSA patients and CPAP-treated OSA patients. These differentially expressed genes were significantly enriched in the regulation of interleukin-1-mediated signaling pathway and ferroptosis-related signaling pathway. Subsequently, 13 ferroptosis-related genes (DRD5, TSC22D3, TFAP2A, STMN1, DDIT3, MYCN, ELAVL1, JUN, DUSP1, MIB1, PSAT1, LCE2C, and MIR27A) were identified from the interaction between differentially expressed genes and FerrDb database, which are regarded as the potential targets of CPAP-treated OSA. These ferroptosis-related genes were mainly involved in cell proliferation and apoptosis and MAPK signaling pathway. Furthermore, DRD5 and TFAP2A were downregulated in OSA patients, which showed good diagnostic properties for OSA, but these abnormal signatures are not reversed with short-term effective CPAP therapy. In summary, the identification of 13 ferroptosis-related genes as potential targets for the CPAP treatment of OSA provides valuable insights into the development of novel, reliable, and accurate therapeutic options.

Lactiplantibacillus plantarum GL001 alleviates jejunal oxidative damage induced by intestinal ischemia-reperfusion injury by influencing jejunal tissue metabolism through the improvement of jejunal microbial composition

Intestinal ischemia-reperfusion (IIR) injury is associated with inflammation and oxidative stress, yet its precise mechanisms remain not fully understood. IIR injury is closely linked to the gut microbiota and its metabolites. The anti-inflammatory and antioxidant effects of Lactiplantibacillus plantarum are specific to IIR. In our study, we conducted a 30-day pre-treatment of SD rats with both a standard strain of Lactiplantibacillus plantarum and Lactiplantibacillus plantarum GL001. After a 7-day cessation of treatment, we induced an IIR injury model to investigate the mechanisms by which Lactiplantibacillus plantarum alleviates IIR damage. The results demonstrate that Lactiplantibacillus plantarum effectively mitigates the inflammatory and oxidative stress damage induced by IIR. Lactiplantibacillus plantarum GL001 can improve the gut microbiota by reducing the abundance of harmful bacteria and increasing the abundance of beneficial bacteria. In IIR intestinal tissue, the levels of secondary bile acids are elevated. The content of the bacterial metabolite Calcimycin increases. Annotations of metabolic pathways suggest that Lactiplantibacillus plantarum GL001 can alleviate IIR damage by modulating calcium-phosphorus homeostasis through the regulation of parathyroid hormone synthesis, secretion, and action. Microbiota-metabolite correlation analysis reveals a significant negative correlation between calcimycin and Lactonacillus and a significant positive correlation between calcimycin and Shigella. There is also a significant positive correlation between calcimycin and secondary bile acids. Lactiplantibacillus plantarum GL001 can alleviate oxidative damage induced by IIR through improvements in gut microbiota and intestinal tissue metabolism.

Calcium's Role and Signaling in Aging Muscle, Cellular Senescence, and Mineral Interactions

Calcium research, since its pivotal discovery in the early 1800s through the heating of limestone, has led to the identification of its multi-functional roles. These include its functions as a reducing agent in chemical processes, structural properties in shells and bones, and significant role in cells relating to this review: cellular signaling. Calcium signaling involves the movement of calcium ions within or between cells, which can affect the electrochemical gradients between intra- and extracellular membranes, ligand binding, enzyme activity, and other mechanisms that determine cell fate. Calcium signaling in muscle, as elucidated by the sliding filament model, plays a significant role in muscle contraction. However, as organisms age, alterations occur within muscle tissue. These changes include sarcopenia, loss of neuromuscular junctions, and changes in mineral concentration, all of which have implications for calcium's role. Additionally, a field of study that has gained recent attention, cellular senescence, is associated with aging and disturbed calcium homeostasis, and is thought to affect sarcopenia progression. Changes seen in calcium upon aging may also be influenced by its crosstalk with other minerals such as iron and zinc. This review investigates the role of calcium signaling in aging muscle and cellular senescence. We also aim to elucidate the interactions among calcium, iron, and zinc across various cells and conditions, ultimately deepening our understanding of calcium signaling in muscle aging.

Carboranyl-1,8-naphthalimide intercalators induce lysosomal membrane permeabilization and ferroptosis in cancer cell lines

The synthesis of carborane-1,8-naphthalimide conjugates and evaluation of their DNA-binding ability and anticancer activity were performed. A series of 4-carboranyl-3-nitro-1,8-naphthalimide derivatives, mitonafide and pinafide analogs, were synthesised via amidation and reductive amination reactions, and their calf thymus DNA (ct-DNA)-binding properties were investigated using circular dichroism, UV-vis spectroscopy, and thermal denaturation. Results showed that conjugates 34-37 interacted very strongly with ct-DNA (ΔT_m = 10.00-13.00 °C), indicating their ability to intercalate with DNA, but did not inhibit the activity of topoisomerase II. The conjugates inhibited the cell growth of the HepG2 cancer cell line in vitro. The same compounds caused the G2M phase arrest. Cell lines treated with these conjugates showed an increase in reactive oxygen species, glutathione, and Fe²⁺ levels, lipid peroxidation, and mitochondrial membrane potential relative to controls, indicating the involvement of ferroptosis. Furthermore, these conjugates caused lysosomal membrane permeabilization in HepG2 cells but not in MRC-5 cells.

Investigating molecular interactions between human transferrin and resveratrol through a unified experimental and computational approach: Role of natural compounds in Alzheimer's disease therapeutics

Disruptions to iron metabolism and iron homeostasis have emerged as significant contributors to the development and progression of Alzheimer's disease (AD). Human transferrin plays a key part in maintaining iron equilibrium throughout the body, highlighting its importance in AD. Many plant-derived compounds and dietary constituents show promise for preventing AD. Polyphenols that are abundant in fruits, vegetables, teas, coffee, and herbs possess neuroprotective attributes. Resveratrol is a natural polyphenol present in various plant sources like grapes, berries, peanuts, and red wine that has garnered research interest due to its wide range of biological activities. Notably, resveratrol exhibits neuroprotective effects that may help prevent or treat AD through multiple mechanisms. In the present study, we employed a combination of molecular docking and all-atom molecular dynamic simulations (MD) along with experimental approaches to unravel the intricate interactions between transferrin and resveratrol deciphering the binding mechanism. Through molecular docking analysis, it was determined that resveratrol occupies the iron binding pocket of transferrin. Furthermore, MD simulations provided a more profound insight into the stability and conformational dynamics of the complex suggesting that the binding of resveratrol introduced localized flexibility, while maintaining overall stability. The spectroscopic observations yielded clear evidence of substantial binding between resveratrol and transferrin, confirming the computational findings. The identified binding mechanism and conformational stability hold potential for advancing the development of innovative therapeutic approaches targeting AD through resveratrol, particularly concerning iron homeostasis. These insights serve as a platform for considering the natural compounds in the realm of AD therapeutics.

On the Role of Iron in Idiopathic Parkinson's Disease

The transition metal characteristics of iron allow it to play a fundamental role in several essential aspects of human life such as the transport of oxygen through hemoglobin or the transport of electrons in the mitochondrial respiratory chain coupled to the synthesis of ATP. However, an excess or deficiency of iron is related to certain pathologies. The maintenance of iron homeostasis is essential to avoid certain pathologies related to iron excess or deficiency. The existence of iron deposits in postmortem tissues of Parkinson's patients has been interpreted as evidence that iron plays a fundamental role in the degenerative process of the nigrostriatal system in this disease. The use of iron chelators has been successful in the treatment of diseases such as transfusion-dependent thalassemia and pantothenate kinase-associated neurodegeneration. However, a clinical study with the iron chelator deferiprone in patients with Parkinson's disease has not shown positive effects but rather worsened clinical symptoms. This suggests that iron may not play a role in the degenerative process of Parkinson's disease.

Biochemical and Molecular Pathways in Neurodegenerative Diseases: An Integrated View

Neurodegenerative diseases (NDDs) like Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS) are defined by a myriad of complex aetiologies. Understanding the common biochemical molecular pathologies among NDDs gives an opportunity to decipher the overlapping and numerous cross-talk mechanisms of neurodegeneration. Numerous interrelated pathways lead to the progression of neurodegeneration. We present evidence from the past pieces of literature for the most usual global convergent hallmarks like ageing, oxidative stress, excitotoxicity-induced calcium butterfly effect, defective proteostasis including chaperones, autophagy, mitophagy, and proteosome networks, and neuroinflammation. Herein, we applied a holistic approach to identify and represent the shared mechanism across NDDs. Further, we believe that this approach could be helpful in identifying key modulators across NDDs, with a particular focus on AD, PD, and ALS. Moreover, these concepts could be applied to the development and diagnosis of novel strategies for diverse NDDs.

Protective Effects of 3'-Epilutein and 3'-Oxolutein against Glutamate-Induced Neuronal Damage

Dietary lutein can be naturally metabolized to 3'-epilutein and 3'-oxolutein in the human body. The epimerization of lutein can happen in acidic pH, and through cooking, 3'-epilutein can be the product of the direct oxidation of lutein in the retina, which is also present in human serum. The 3'-oxolutein is the main oxidation product of lutein. Thus, the allylic oxidation of dietary lutein can result in the formation of 3'-oxolutein, which may undergo reduction either to revert to dietary lutein or epimerize to form 3'-epilutein. We focused on the effects of 3'-epilutein and 3'-oxolutein itself and on glutamate-induced neurotoxicity on SH-SY5Y human neuroblastoma cells to identify the possible alterations in oxidative stress, inflammation, antioxidant capacity, and iron metabolism that affect neurological function. ROS measurements were performed in the differently treated cells. The inflammatory state of cells was followed by TNFα, IL-6, and IL-8 cytokine ELISA measurements. The antioxidant status of the cells was determined by the total antioxidant capacity kit assay. The alterations of genes related to ferroptosis and lipid peroxidation were followed by gene expression measurements; then, thiol measurements were performed. Lutein metabolites 3'-epilutein and 3'-oxolutein differently modulated the effect of glutamate on ROS, inflammation, ferroptosis-related iron metabolism, and lipid peroxidation in SH-SY5Y cells. Our results revealed the antioxidant and anti-inflammatory features of 3'-epilutein and 3'-oxolutein as possible protective agents against glutamate-induced oxidative stress in SH-SY5Y cells, with greater efficacy in the case of 3'-epilutein.

USP11-mediated LSH deubiquitination inhibits ferroptosis in colorectal cancer through epigenetic activation of CYP24A1

Ferroptosis is an iron-dependent form of regulated cell death characterized by lipid peroxidation. Colorectal cancer (CRC) cells evade ferroptosis despite their requirement of substantial iron and reactive oxygen species (ROS) to sustain active metabolism and extensive proliferation. However, the underlying mechanism is unclear. Herein, we report the role of lymphoid-specific helicase (LSH), a chromatin-remodeling protein, in suppressing erastin-induced ferroptosis in CRC cells. We demonstrate that erastin treatment leads to dose- and time-dependent downregulation of LSH in CRC cells, and depletion of LSH increases cell sensitivity to ferroptosis. Mechanistically, LSH interacts with and is stabilized by ubiquitin-specific protease 11 (USP11) via deubiquitination; this interaction was disrupted by erastin treatment, resulting in increased ubiquitination and LSH degradation. Moreover, we identified cytochrome P450 family 24 subfamily A member 1 (CYP24A1) as a transcriptional target of LSH. LSH binds to the CYP24A1 promoter, promoting nucleosome eviction and reducing H3K27me3 occupancy, thus leading to transcription of CYP24A1. This cascade inhibits excessive intracellular Ca2+ influx, thereby reducing lipid peroxidation and ultimately conferring resistance to ferroptosis. Importantly, aberrant expression of USP11, LSH, and CYP24A1 is observed in CRC tissues and correlates with poor patient prognosis. Taken together, our study demonstrates the crucial role of the USP11/LSH/CYP24A1 signaling axis in inhibiting ferroptosis in CRC, highlighting its potential as a therapeutic target in CRC treatment.

Critical Roles of the Cysteine-Glutathione Axis in the Production of γ-Glutamyl Peptides in the Nervous System

γ-Glutamyl moiety that is attached to the cysteine (Cys) residue in glutathione (GSH) protects it from peptidase-mediated degradation. The sulfhydryl group of the Cys residue represents most of the functions of GSH, which include electron donation to peroxidases, protection of reactive sulfhydryl in proteins via glutaredoxin, and glutathione conjugation of xenobiotics, whereas Cys-derived sulfur is also a pivotal component of some redox-responsive molecules. The amount of Cys that is available tends to restrict the capacity of GSH synthesis. In in vitro systems, cystine is the major form in the extracellular milieu, and a specific cystine transporter, xCT, is essential for survival in most lines of cells and in many primary cultivated cells as well. A reduction in the supply of Cys causes GPX4 to be inhibited due to insufficient GSH synthesis, which leads to iron-dependent necrotic cell death, ferroptosis. Cells generally cannot take up GSH without the removal of γ-glutamyl moiety by γ-glutamyl transferase (GGT) on the cell surface. Meanwhile, the Cys-GSH axis is essentially common to certain types of cells; primarily, neuronal cells that contain a unique metabolic system for intercellular communication concerning γ-glutamyl peptides. After a general description of metabolic processes concerning the Cys-GSH axis, we provide an overview and discuss the significance of GSH-related compounds in the nervous system.

Wnt5a/Ca2+ signaling regulates silica-induced ferroptosis in mouse macrophages by altering ER stress-mediated redox balance

Silicosis is a chronic pulmonary disease characterized by diffuse fibrosis of lung caused by the deposition of silica dust (SiO₂). The inhaled silica-induced oxidative stress, ROS production and macrophage ferroptosis are key drivers of the pathological process of silicosis. However, mechanisms that involved in the silica-induced macrophage ferroptosis and its contributions to pathogenesis of silicosis remain elusive. In the present study, we showed that silica induced murine macrophage ferroptosis, accompanied by elevation of inflammatory responses, Wnt5a/Ca²⁺ signaling activation, and concurrent increase of endoplasmic reticulum (ER) stress and mitochondrial redox imbalance in vitro and vivo. Mechanistic study further demonstrated that Wnt5a/Ca²⁺ signaling played a key role in silica-induced macrophage ferroptosis by modulating ER stress and mitochondrial redox balance. The presence of Wnt5a/Ca²⁺ signaling ligand Wnt5a protein increased the silica-induced macrophage ferroptosis by activating ER-mediated immunoglobulin heavy chain binding protein (Bip)-C/EBP homology protein (Chop) signaling cascade, reducing the expression of negative regulators of ferroptosis, glutathione peroxidase 4 (Gpx4) and solute carrier family 7 member 11 (Slc7a11), subsequentially increasing lipid peroxidation. The pharmacologic inhibition of Wnt5a signaling or block of calcium flow exhibited an opposite effect to Wnt5a, resulted in the reduction of ferroptosis and the expression of Bip-Chop signaling molecules. These findings were further corroborated by the addition of ferroptosis activator Erastin or inhibitor ferrostatin-1. These results provide a mechanism by which silica activates Wnt5a/Ca²⁺ signaling and ER stress, sequentially leads to redox imbalance and ferroptosis in mouse macrophage cells.

Ryanodine Receptor Mediated Calcium Release Contributes to Ferroptosis Induced in Primary Hippocampal Neurons by GPX4 Inhibition

Ferroptosis, a newly described form of regulated cell death, is characterized by the iron-dependent accumulation of lipid peroxides, glutathione depletion, mitochondrial alterations, and enhanced lipoxygenase activity. Inhibition of glutathione peroxidase 4 (GPX4), a key intracellular antioxidant regulator, promotes ferroptosis in different cell types. Scant information is available on GPX4-induced ferroptosis in hippocampal neurons. Moreover, the role of calcium (Ca2+) signaling in ferroptosis remains elusive. Here, we report that RSL3, a selective inhibitor of GPX4, caused dendritic damage, lipid peroxidation, and induced cell death in rat primary hippocampal neurons. Previous incubation with the ferroptosis inhibitors deferoxamine or ferrostatin-1 reduced these effects. Likewise, preincubation with micromolar concentrations of ryanodine, which prevent Ca2+ release mediated by Ryanodine Receptor (RyR) channels, partially protected against RSL3-induced cell death. Incubation with RSL3 for 24 h suppressed the cytoplasmic Ca2+ concentration increase induced by the RyR agonist caffeine or by the SERCA inhibitor thapsigargin and reduced hippocampal RyR2 protein content. The present results add to the current understanding of ferroptosis-induced neuronal cell death in the hippocampus and provide new information both on the role of RyR-mediated Ca2+ signals on this process and on the effects of GPX4 inhibition on endoplasmic reticulum calcium content.

Homo sapiens—A Species Not Designed for Space Flight: Health Risks in Low Earth Orbit and Beyond, Including Potential Risks When Traveling beyond the Geomagnetic Field of Earth

Homo sapiens and their predecessors evolved in the context of the boundary conditions of Earth, including a 1 g gravity and a geomagnetic field (GMF). These variables, plus others, led to complex organisms that evolved under a defined set of conditions and define how humans will respond to space flight, a circumstance that could not have been anticipated by evolution. Over the past ~60 years, space flight and living in low Earth orbit (LEO) have revealed that astronauts are impacted to varying degrees by such new environments. In addition, it has been noted that astronauts are quite heterogeneous in their response patterns, indicating that such variation is either silent if one remained on Earth, or the heterogeneity unknowingly contributes to disease development during aging or in response to insults. With the planned mission to deep space, humans will now be exposed to further risks from radiation when traveling beyond the influence of the GMF, as well as other potential risks that are associated with the actual loss of the GMF on the astronauts, their microbiomes, and growing food sources. Experimental studies with model systems have revealed that hypogravity conditions can influence a variety biological and physiological systems, and thus the loss of the GMF may have unanticipated consequences to astronauts’ systems, such as those that are electrical in nature (i.e., the cardiovascular system and central neural systems). As astronauts have been shown to be heterogeneous in their responses to LEO, they may require personalized countermeasures, while others may not be good candidates for deep-space missions if effective countermeasures cannot be developed for long-duration missions. This review will discuss several of the physiological and neural systems that are affected and how the emerging variables may influence astronaut health and functioning.

COVID-19-induced neurological symptoms: focus on the role of metal ions

Neurological symptoms are prevalent in both the acute and post-acute phases of coronavirus disease 2019 (COVID-19), and they are becoming a major concern for the prognosis of COVID-19 patients. Accumulation evidence has suggested that metal ion disorders occur in the central nervous system (CNS) of COVID-19 patients. Metal ions participate in the development, metabolism, redox and neurotransmitter transmission in the CNS and are tightly regulated by metal ion channels. COVID-19 infection causes neurological metal disorders and metal ion channels abnormal switching, subsequently resulting in neuroinflammation, oxidative stress, excitotoxicity, neuronal cell death, and eventually eliciting a series of COVID-19-induced neurological symptoms. Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for mitigating COVID-19-induced neurological symptoms. This review provides a summary for the latest advances in research related to the physiological and pathophysiological functions of metal ions and metal ion channels, as well as their role in COVID-19-induced neurological symptoms. In addition, currently available modulators of metal ions and their channels are also discussed. Collectively, the current work offers a few recommendations according to published reports and in-depth reflections to ameliorate COVID-19-induced neurological symptoms. Further studies need to focus on the crosstalk and interactions between different metal ions and their channels. Simultaneous pharmacological intervention of two or more metal signaling pathway disorders may provide clinical advantages in treating COVID-19-induced neurological symptoms.

Development and validation of a novel ferroptosis‑related lncRNA prognostic signature for pancreatic adenocarcinoma

Long non‑coding RNAs (lncRNAs) serve a pivotal role in the regulation of cancer cell ferroptosis. However, the prognostic value of ferroptosis‑related lncRNAs in pancreatic adenocarcinoma (PAAD) largely remains unclear. We aimed at constructing a lncRNA‑based signature to improve the prognosis prediction of PAAD. In the present study, the transcriptome profiling data and clinical information of patients with PAAD were obtained from The Cancer Genome Atlas (TCGA) and International Cancer Gene Consortium (ICGC) databases. Univariate Cox regression analysis of the TCGA cohort demonstrated that 26 ferroptosis‑related lncRNAs had significant prognostic value for PAAD (all P<0.01). Least absolute shrinkage and selection operator regression and multivariate Cox proportional hazards regression analyses were performed to construct a prognostic ferroptosis‑related lncRNA signature (FRLS) comprising nine ferroptosis‑related lncRNAs. The efficacy of this FRLS was verified in the training (TCGA) and validation (ICGC) cohorts. Based on the risk model, high risk scores were significantly correlated with poor overall survival (OS) (hazard ratio, 1.314; 95% confidence interval, 1.218‑1.418; P<0.001). The receiver operating characteristic curves and principal component analysis further demonstrated the robust prognostic ability of the FRLS. Furthermore, a nomogram with favorable predictive efficacy for the prediction of OS was constructed based on the FRLS and clinical features. Gene set enrichment analysis demonstrated that the genes in the FRLS participated in a number of cancer‑associated immunoregulatory pathways. Importantly, it was demonstrated that immune infiltration and response to cancer immunotherapy differed significantly between the high and low‑risk groups according to the FRLS. In conclusion, the risk signature based on the FRLS has potential for the clinical prediction of prognosis and immunotherapy response in patients with PAAD.

Remodeling tumor microenvironment with natural products to overcome drug resistance

With cancer incidence rates continuing to increase and occurrence of resistance in drug treatment, there is a pressing demand to find safer and more effective anticancer strategy for cancer patients. Natural products, have the advantage of low toxicity and multiple action targets, are always used in the treatment of cancer prevention in early stage and cancer supplement in late stage. Tumor microenvironment is necessary for cancer cells to survive and progression, and immune activation is a vital means for the tumor microenvironment to eliminate cancer cells. A number of studies have found that various natural products could target and regulate immune cells such as T cells, macrophages, mast cells as well as inflammatory cytokines in the tumor microenvironment. Natural products tuning the tumor microenvironment via various mechanisms to activate the immune response have immeasurable potential for cancer immunotherapy. In this review, it highlights the research findings related to natural products regulating immune responses against cancer, especially reveals the possibility of utilizing natural products to remodel the tumor microenvironment to overcome drug resistance.

The mechanism of ferroptosis regulating oxidative stress in ischemic stroke and the regulation mechanism of natural pharmacological active components

Cerebrovascular diseases, such as ischemic stroke, pose serious medical challenges worldwide due to their high morbidity and mortality and limitations in clinical treatment strategies. Studies have shown that reactive oxygen species (ROS)-mediated inflammation, excitotoxicity, and programmed cell death of each neurovascular unit during post-stroke hypoxia and reperfusion play an important role in the pathological cascade. Ferroptosis, a programmed cell death characterized by iron-regulated accumulation of lipid peroxidation, is caused by abnormal metabolism of lipids, glutathione (GSH), and iron, and can accelerate acute central nervous system injury. Recent studies have gradually uncovered the pathological process of ferroptosis in the neurovascular unit of acute stroke. Some drugs such as iron chelators, ferrostatin-1 (Fer-1) and liproxstatin-1 (Lip-1) can protect nerves after neurovascular unit injury in acute stroke by inhibiting ferroptosis. In addition, combined with our previous studies on ferroptosis mediated by natural compounds in ischemic stroke, this review summarized the progress in the regulation mechanism of natural chemical components and herbal chemical components on ferroptosis in recent years, in order to provide reference information for future research on ferroptosis and lead compounds for the development of ferroptosis inhibitors.

Screening of Differentially Expressed Iron Death-Related Genes and the Construction of Prognosis Model in Patients with Renal Clear Cell Carcinoma

Objective

In this study, we used the TCGA database and ICGC database to establish a prognostic model of iron death associated with renal cell carcinoma, which can provide predictive value for the identification of iron death-related genes and clinical treatment of renal clear cell carcinoma.

Methods

The gene expression profiles and clinical data of renal clear cell carcinoma and normal tissues were obtained in the TCGA database and ICGC database, and the differential genes related to iron death were screened out. The differential genes were screened out by single and multifactor Cox risk regression model. R software, "edge" package (version 4.0), was used to identify the DELs of 551 transcriptional gene samples and 522 clinical samples. The risk prediction model with genes was established to analyze the correlation between the genes in the established model and clinical characteristics, Through the final screening of iron death related genes, it can be used to predict the prognosis of renal clear cell carcinoma and provide advice for clinical targeted therapy.

Results

Seven iron death differential genes (CLS2, FANCD2, PHKG2, ACSL3, ATP5MC3, CISD1, PEBP1) associated with renal clear cell carcinoma were finally screened and were refer to previous relevant studies. These genes are closely related to iron death and have great value for the prognosis of renal clear cell carcinoma.

Conclusion

Seven iron death genes can accurately predict the survival of patients with renal clear cell carcinoma.

Downregulation of HULC Induces Ferroptosis in Hepatocellular Carcinoma via Targeting of the miR-3200-5p/ATF4 Axis

Hepatocellular carcinoma is a malignant tumor that poses a serious threat to human health. Ferroptosis, which represents an identified type of regulated iron-dependent cell death, may play an important role in hepatocellular carcinoma. However, it is unclear as to whether ferroptosis is involved with the mechanisms of lncRNA HULC in liver cancer cells. Here, we show that knockdown of HULC increases ferroptosis and oxidative stress in liver cancer cells. We also found changes in some related miRNAs in cells treated with HULC siRNA. Differential miRNA expression levels were determined with the use of high-throughput sequencing and prediction target genes identified using bioinformatics analysis. HULC was found to function as a ceRNA of miR-3200-5p, and miR-3200-5p regulates ferroptosis by targeting ATF4, resulting in the inhibition of proliferation and metastasis within HCC cells. In summary, these findings illuminate some of the molecular mechanisms through which downregulation of HULC induces liver cancer cell ferroptosis by targeting the miR-3200-5p/ATF4 axis to modulate the development of hepatocellular carcinoma.

Bromodomains in Human-Immunodeficiency Virus-Associated Neurocognitive Disorders: A Model of Ferroptosis-Induced Neurodegeneration

Human immunodeficiency virus (HIV)-associated neurocognitive disorders (HAND) comprise a group of illnesses marked by memory and behavioral dysfunction that can occur in up to 50% of HIV patients despite adequate treatment with combination antiretroviral drugs. Iron dyshomeostasis exacerbates HIV-1 infection and plays a major role in Alzheimer's disease pathogenesis. In addition, persons living with HIV demonstrate a high prevalence of neurodegenerative disorders, indicating that HAND provides a unique opportunity to study ferroptosis in these conditions. Both HIV and combination antiretroviral drugs increase the risk of ferroptosis by augmenting ferritin autophagy at the lysosomal level. As many viruses and their proteins exit host cells through lysosomal exocytosis, ferroptosis-driving molecules, iron, cathepsin B and calcium may be released from these organelles. Neurons and glial cells are highly susceptible to ferroptosis and neurodegeneration that engenders white and gray matter damage. Moreover, iron-activated microglia can engage in the aberrant elimination of viable neurons and synapses, further contributing to ferroptosis-induced neurodegeneration. In this mini review, we take a closer look at the role of iron in the pathogenesis of HAND and neurodegenerative disorders. In addition, we describe an epigenetic compensatory system, comprised of bromodomain-containing protein 4 (BRD4) and microRNA-29, that may counteract ferroptosis by activating cystine/glutamate antiporter, while lowering ferritin autophagy and iron regulatory protein-2. We also discuss potential interventions for lysosomal fitness, including ferroptosis blockers, lysosomal acidification, and cathepsin B inhibitors to achieve desirable therapeutic effects of ferroptosis-induced neurodegeneration.

The Role of AMP-activated Protein Kinase in Oxytosis/Ferroptosis: Protector or Potentiator?

Significance: Evidence for a role for the oxytosis/ferroptosis regulated cell death pathway in aging and neurodegenerative diseases has been growing over the past few years. Because of this, there is an increasing necessity to identify endogenous signaling pathways that can be modulated to protect cells from this form of cell death. Recent Advances: Recently, several studies have identified a protective role for the AMP-activated protein kinase (AMPK)/acetyl CoA carboxylase 1 (ACC1) pathway in oxytosis/ferroptosis. However, there are also a number of studies suggesting that this pathway contributes to cell death initiated by various inducers of oxytosis/ferroptosis. Critical Issues: The goals of this review are to provide an overview and analysis of the published studies and highlight specific areas where more research is needed. Future Directions: Much remains to be learned about AMPK signaling in oxytosis/ferroptosis, especially the conditions where it is protective. Furthermore, the role of AMPK signaling in the brain and especially the aging brain needs further investigation.

Acetaminophen alleviates ferroptosis in mice with sepsis-associated encephalopathy via the GPX4 pathway

Sepsis-associated encephalopathy (SAE) is a cognitive impairment caused by sepsis, associated with increased morbidity and death. And acetaminophen (APAP) is a promising therapeutic medicine for SAE treatment. This research was designed to determine whether APAP alleviates SAE by attenuating ferroptosis and mediating the glutathione peroxidase (GPX4) pathway. The cecal ligation and puncture (CLP) approach was used to establish septic mouse models. The survival rates for 7 days were determined. The Morris water maze (MWM) was utilized to assess cognitive function. Hematoxylin and eosin (HE) staining identified histopathologic alterations in hippocampal tissue. Mitochondrial damage was discovered in hippocampal tissue using transmission electron microscopy (TEM). The reactive oxygen (ROS) levels in hippocampal tissue were measured using commercial assays. Septic cell models were produced using HT22 cells grown with 1 μg/ml lipopolysaccharide (LPS). ROS were quantified using immunofluorescence. Ferroptosis-related protein expression levels in hippocampal tissue and HT22 cells were measured using western blotting. To evaluate the iron content of hippocampal tissue and HT22 cells, commercial kits were employed. According to the findings, APAP improved survival rates, lowered hippocampal and mitochondrial damage, and improve cognitive impairment. In both animal and cell studies, APAP reduced iron content, ROS, glutamate antiporter (xCT), 4-hydroxy-2-nonenal (4-HNE) levels but increased GPX4 expression. However, RSL3, a GPX4 inhibitor that acts as a ferroptosis activator, decreased the protective properties of APAP in vitro. Our findings suggest that APAP reduces sepsis-induced cognitive impairment by reducing ferroptosis, which is mediated by the GPX4 signaling pathway.