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Alzheimer's disease (AD) is characterized by cognitive decline and the accumulation of amyloid-beta plaques and hyperphosphorylated tau protein. The role of tau lactylation at the K677 site in AD progression is not well understood. This study explores how tau K677 lactylation affects ferritinophagy, ferroptosis, and their functions in an AD mouse model. Results show that mutating the K677 site to R reduces tau lactylation and inhibits ferroptosis by regulating iron metabolism factors like NCOA4 and FTH1.Tau-mutant mice showed improved memory and learning skills compared to wild-type mice. The mutation also reduced neuronal damage and was associated with decreased tau lactylation at the K677 site, regardless of phosphorylated tau levels. Gene set enrichment analysis showed that lactylation at this site was linked to the MAPK pathway, which was important for ferritinophagy in AD mice. In summary, our research indicates that the K677 mutation in tau protein may protect against AD by influencing ferritinophagy and ferroptosis through MAPK signaling pathways. Understanding these modifications in tau could lead to new treatments for AD. [Display omitted] • The K677 mutation in the tau protein may confer a protective effect against Alzheimer's disease. • The results show that replacing the K677 residue with arginine reduces tau lactylation and inhibits ferroptosis. • Decreased neuronal damage was linked to reduced tau lactylation at K677, independent of phosphorylated tau levels. [ABSTRACT FROM AUTHOR]

Irradiation of the head and neck inevitably leads to decreased salivary gland function. It is postulated that radiation generates excessive reactive oxygen species (ROS) and reduces salivary gland function by ferroptosis, a new cell death mechanism; however, research in this area is currently lacking. In this study, we investigated the effects of amifostine and melatonin on acute salivary gland dysfunction and ferroptosis. Thirty-two Sprague Dawley rats were divided into four groups: control, radiation, radiation + amifostine, and radiation + melatonin. ROS; iron levels; glutathione peroxidase 4; 4-hydroxynonenal; various cytokines; and fibrosis and salivary gland functional markers were measured. Western blotting was used to detect ferritinophagy. After irradiation, we observed an increase in iron levels, ROS generation, oxidized glutathione, lipid peroxidation, fibrosis, and salivary gland dysfunction and a decrease in glutathione peroxidase 4 in salivary gland tissue. Treatment with amifostine or melatonin decreased the ferroptotic response and improved acute salivary gland function 10 days after radiation. The increase in iron levels associated with ferritinophagy was reduced after treatment with amifostine or melatonin. Our results demonstrate that radiation-induced acute salivary gland dysfunction is associated with ferroptosis and ferritinophagy. Amifostine and melatonin inhibit radiation-induced ferroptosis and ferritinophagy in the salivary gland and prevent acute salivary gland dysfunction 10 days after radiation. [ABSTRACT FROM AUTHOR]

Mammalian cochlea spiral ganglion neurons (SGNs) are crucial for sound transmission, they can be damaged by chemotherapy drug cisplatin and lead to irreversible sensorineural hearing loss (SNHL), while such damage can also render cochlear implants ineffective. However, the mechanisms underlying cisplatin‐induced SGNs damage and subsequent SNHL are still under debate and there is no currently effective clinical treatment. Here, this study demonstrates that ferroptosis is triggered in SGNs following exposure to cisplatin. Inhibiting ferroptosis protects against cisplatin‐induced SGNs damage and hearing loss, while inducing ferroptosis intensifies these effects. Furthermore, cisplatin prompts nuclear receptor coactivator 4 (NCOA4)‐mediated ferritinophagy in SGNs, while knocking down NCOA4 mitigates cisplatin‐induced ferroptosis and hearing loss. Notably, the upstream regulator of NCOA4 is identified and transcription factor forkhead box O1 (FOXO1) is shown to directly suppress NCOA4 expression in SGNs. The knocking down of FOXO1 amplifies NCOA4‐mediated ferritinophagy, increases ferroptosis and lipid peroxidation, while disrupting the interaction between FOXO1 and NCOA4 in NCOA4 knock out mice prevents the cisplatin‐induced SGN ferroptosis and hearing loss. Collectively, this study highlights the critical role of the FOXO1‐NCOA4 axis in regulating ferritinophagy and ferroptosis in cisplatin‐induced SGNs damage, offering promising therapeutic targets for SNHL mitigation. [ABSTRACT FROM AUTHOR]

There are increasing concerns regarding the rapid expansion of polystyrene nanoplastics (PS-NPs), which could impact human health. Previous studies have shown that nanoplastics can be transferred from mothers to offspring through the placenta and breast milk, resulting in cognitive deficits in offspring. However, the neurotoxic effects of maternal exposure on offspring and its mechanisms remain unclear. In this study, PS-NPs (50 nm) were gavaged to female rats throughout gestation and lactation to establish an offspring exposure model to study the neurotoxicity and behavioral changes caused by PS-NPs on offspring. Neonatal rat hippocampal neuronal cells were used to investigate the pathways through which NPs induce neurodevelopmental toxicity in offspring rats, using iron inhibitors, autophagy inhibitors, reactive oxygen species (ROS) scroungers, P53 inhibitors, and NCOA4 inhibitors. We found that low PS-NPs dosages can cause ferroptosis in the hippocampus of the offspring, resulting in a decline in the cognitive, learning, and memory abilities of the offspring. PS-NPs induced NOCA4-mediated ferritinophagy and promoted ferroptosis by inciting ROS production to activate P53-mediated ferritinophagy. Furthermore, the levels of the antioxidant factors glutathione peroxidase 4 (GPX4) and glutathione (GSH), responsible for ferroptosis, were reduced. In summary, this study revealed that consumption of PS-NPs during gestation and lactation can cause ferroptosis and damage the hippocampus of offspring. Our results can serve as a basis for further research into the neurodevelopmental effects of nanoplastics in offspring. [ABSTRACT FROM AUTHOR]

AIM: This study aimed to explore the induction of ferroptosis in non-small-cell lung cancer （NSCLC） cells by tubeimoside II （TBMS II） and to elucidate the underlying molecular mechanisms. METHODS: H460 NSCLC cells were cultured in vitro. Cell survival rates were assessed by using MTT assays, and doses of TBMS II resulting in below 50% survival were selected for further experimentation. Cell migration was evaluated using Transwell assays and the effects of TBMS II on H460 cell proliferation were assessed by colony formation assays. Flow cytometry and fluorescence microscopy were used to assess changes in lipid peroxidation （lipid ROS）, and the levels of GSH, T-AOC, MDA, and Fe2+ were measured using commercial kits. Protein levels of GPX4, SLC7A11, FTH1, NCOA4, P62, and LC3 were examined using Western blot. Changes in mitochondrial structure were detected by transmission electron microscopy, and immunofluorescence was used to assess LC3 co-localization of FTH1 and NCOA4, as well as co-localization of LC3 and NCOA4 with lysosomes. RESULTS: Compared with the control group, TBMS II dose-dependently reduced H460 cell viability, migration, and clone formation, accompanied by the appearance of vacuoles within the cells. TBMS II treatment also led to decreased GSH and T-AOC levels, while increasing the cellular contents of MDA, indicating oxidative stress. Additionally, there was a decrease in the expression of the antioxidant proteins SLC7A11 and GPX4 in the cells, while lipid ROS and Fe2+ levels were increased in proportion to the TBMS II concentration. The ferroptosis inhibitor ferrostatin-1 reversed cell death caused by TBMS II, suggesting ferroptosis induction. Furthermore, increasing the TBMS II concentration resulted in an upregulation of the autophagy marker proteins LC3 II/LC3 I and P62, indicative of increased autophagy. TBMS II also affected mitochondrial morphology in the cells, as seen in reduced mitochondrial fluorescence intensity. Protein expression of NCOA4 increased with higher TBMS II concentrations, while that of FTH1 decreased. Co-localization of LC3 II with FTH1 and NCOA4, as well as the lysosomal association of LC3 II and FTH1, also increased in a dosedependent manner. CONCLUSION: TBMS II induces ferritinophagy in H460 cells, leading to decreased cell viability and increased ferroptosis. [ABSTRACT FROM AUTHOR]

Ferroptosis, a form of cell death driven by iron‐dependent lipid peroxidation, is emerging as a promising target in cancer therapy. It is regulated by a network of molecules and pathways that modulate lipid metabolism, iron homeostasis and redox balance, and related processes. However, there are still numerous regulatory molecules intricately involved in ferroptosis that remain to be identified. Here, we indicated that suppression of Golgi protein acyl‐coenzyme A binding domain A containing 3 (ACBD3) increased the sensitivity of Henrieta Lacks and PANC1 cells to ferroptosis. ACBD3 knockdown increases labile iron levels by promoting ferritinophagy. This increase in free iron, coupled with reduced levels of glutathione peroxidase 4 due to ACBD3 knockdown, leads to the accumulation of reactive oxygen species and lipid peroxides. Moreover, ACBD3 knockdown also results in elevated levels of polyunsaturated fatty acid‐containing glycerophospholipids through mechanisms that remain to be elucidated. Furthermore, inhibition of ferrtinophagy in ACBD3 downregulated cells by knocking down the nuclear receptor co‐activator 4 or Bafilomycin A1 treatment impeded ferroptosis. Collectively, our findings highlight the pivotal role of ACBD3 in governing cellular resistance to ferroptosis and suggest that pharmacological manipulation of ACBD3 levels is a promising strategy for cancer therapy. [ABSTRACT FROM AUTHOR]

Dexmedetomidine (DEX) has been confirmed to exert neuroprotective effects in various nerve injury models by regulating ferroptosis, including spinal cord injury (SCI). Although it has been established that CDGSH iron sulfur domain 2 (CISD2) can regulate ferroptosis, whether DEX can regulate ferroptosis by CISD2 in SCI remains unclear. Lidocaine was used to induce PC12 cells and stimulate rats to establish SCI models in vitro and in vivo. MTT assays were performed to analyze cell viability. Ferroptosis was assessed by determining the levels of cellular reactive axygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and Fe2+. Ferritinophagy was analyzed by LysoTracker staining, FerroOrange staining, and immunofluorescence. Western blotting was carried out to quantify the levels of several proteins. Fluorescence microscopy was also used to observe cell autophagy. The morphology of mitochondria within the tissue was observed under transmission electron microscopy (TEM). DEX treatment weakened lidocaine-induced elevation of ROS, Fe2+, and MDA and reduced GSH in PC12 cells, indicating that DEX treatment weakened lidocaine-induced ferroptosis in PC12 cells. Similarly, lidocaine promoted autophagy, Fe2+, and microtubule-associated protein 1 light chain 3 (LC3) in PC12 cells and suppressed ferritin and p62 protein levels, indicating that DEX could weaken lidocaine-induced ferritinophagy in PC12 cells. DEX treatment improved the BBB score, reduced tissue damage, increased the number of neurons, and alleviated mitochondrial damage by inhibiting ferroptosis and ferritinophagy in lidocaine-induced SCI rat models. The decreased CISD2, ferritin heavy chain 1 (FTH1), solute carrier family 7-member 11-glutathione (SLC7A11), and glutathione peroxidase 4 (GPX4) protein levels and the elevated nuclear receptor coactivator 4 (NCOA4) protein levels in rat models in the lidocaine group were weakened by DEX treatment. Moreover, CISD2 inhibition reversed the inhibitory effects of DEX treatment on lidocaine-induced ferroptosis and ferritinophagy in PC12 cells significantly. Taken together, DEX treatment could impair lidocaine-induced SCI by inhibiting ferroptosis and ferritinophagy by upregulating CISD2 in rat models. [ABSTRACT FROM AUTHOR]

Chlorosis in azaleas is characterized by an interveinal yellowing of leaves that is typically caused by a deficiency of iron. This condition is usually due to the inability of cells to properly acquire iron as a consequence of unfavorable conditions, such as an elevated pH, rather than insufficient iron levels. The causes and effects of chlorosis were found to have similarities with those pertaining to a recently presented hypothesis that describes a pathogenic process in Alzheimer disease. This hypothesis states that iron becomes sequestered (e.g., by amyloid β and tau), causing a functional deficiency of iron that disrupts biochemical processes leading to neurodegeneration. Additional mechanisms that contribute to iron becoming unavailable include iron-containing structures not undergoing proper recycling (e.g., disrupted mitophagy and altered ferritinophagy) and failure to successfully translocate iron from one compartment to another (e.g., due to impaired lysosomal acidification). Other contributors to a functional deficiency of iron in patients with Alzheimer disease include altered metabolism of heme or altered production of iron-containing proteins and their partners (e.g., subunits, upstream proteins). A review of the evidence supporting this hypothesis is presented. Also, parallels between the mechanisms underlying a functional iron-deficient state in Alzheimer disease and those occurring for chlorosis in plants are discussed. Finally, a model describing the generation of a functional iron deficiency in Alzheimer disease is put forward. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA), a secondary fungal metabolite known for its nephrotoxic effects, is prevalent in various feeds and food items. Our recent study suggests that OTA-induced nephrotoxicity is linked to the Sigma-1 receptor (Sig-1R)-mediated mitochondrial pathway apoptosis in human proximal tubule epithelial-originated kidney-2 (HK-2) cells. However, the contribution of Sig-1R to OTA-induced nephrotoxicity involving other forms of regulated cell death, such as ferroptosis, remains unexplored. In this investigation, cell viability, malondialdehyde (MDA) levels, glutathione (GSH) levels, and protein expressions in HK-2 cells treated with OTA and/or Ferrostatin-1/blarcamesine hydrochloride/BD1063 dihydrochloride were assessed. The results indicate that a 24 h-treatment with 1 μM OTA significantly induces ferroptosis by inhibiting Sig-1R, subsequently promoting nuclear receptor coactivator 4 (NCOA4), long-chain fatty acid-CoA ligase 4 (ACSL4), arachidonate 5-lipoxygenase (ALOX5), autophagy protein 5 (ATG5), and ATG7, inhibiting ferritin heavy chain (FTH1), solute carrier family 7 member 11 (SLC7A11/xCT), glutathione peroxidase 4 (GPX4), peroxiredoxin 6 (PRDX6), and ferroptosis suppressor protein 1 (FSP1), reducing GSH levels, and increasing MDA levels (P < 0.05). In conclusion, OTA induces ferroptosis by inhibiting Sig-1R, subsequently promoting ferritinophagy, inhibiting GPX4/FSP1 antioxidant systems, reducing GSH levels, and ultimately increasing lipid peroxidation levels in vitro. [ABSTRACT FROM AUTHOR]

Ferroptosis is a new programmed cell death characterized by iron-dependent lipid peroxidation. Targeting ferroptosis is considered a promising strategy for anti-cancer therapy. Recently, natural compound has gained increased attention for their advantage in cancer treatment, and the exploration of natural compounds as ferroptosis inducers offers a hopeful avenue for advancing cancer treatment modalities. Emodin is a natural anthraquinone derivative in many widely used Chinese medicinal herbs. In our previous study, we predicted that the anti-cancer effect of Emodin might related to ferroptosis by using RNA-seq in colorectal cancer (CRC). Thus, in this study, we aim to investigate the molecular mechanism underlying Emodin-mediated ferroptosis in CRC. Cell-based assays including CCK-8, colony formation, EdU, and Annexin V/PI staining were employed to assess Emodin's impact on cell proliferation and apoptosis. Furthermore, various techniques such as FerroOrange staining, C11-BODIPY 581/591 staining, iron, MDA, GSH detection assay and transmission electron microscopy were performed to examine the role of Emodin in ferroptosis. Additionally, specific NCOA4 knockdown cell lines were generated to elucidate the involvement of NCOA4 in Emodin-induced ferroptosis. Moreover, the effects of Emodin on ferroptosis were further confirmed through the application of inhibitors, including Ferrostatin-1, 3-MA, DFO, and PMA. As a results, Emodin inhibited proliferation and induced apoptosis in CRC cells. Emodin could decrease GSH content, xCT and GPX4 expression, meanwhile increasing ROS generation, MDA, and lipid peroxidation, and these effects could reverse by ferroptosis inhibitor, Ferostatin-1, iron chelator DFO, autophagy inhibitor 3-MA and NCOA4 silencing. Moreover, Emodin could inactivate NF-κb pathway, and PMA, an activator of NF-κb pathway could alleviate Emodin-induced ferroptosis in CRC cells. Xenograft mouse model also showed that Emodin suppressed tumor growth and induced ferroptosis in vivo. In conclusion, these results suggested that Emodin induced ferroptosis through NCOA4-mediated ferritinophagy by inactivating NF-κb pathway in CRC cells. These findings not only identified a novel role for Emodin in ferroptosis but also indicated that Emodin may be a valuable candidate for the development of an anti-cancer agent. [ABSTRACT FROM AUTHOR]

Protein tyrosine phosphatase receptor type C (PTPRC) is reported to function as an oncogenic role in various cancer. However, the studies on the roles of PTPRC in osteosarcoma (OS) are limited. This study aimed to explore the potentials of PTPRC in OS. mRNA levels were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Protein expression was detected by western blot. Lysosome biogenesis was determined using immunofluorescence. The binding sites of transcription factor EB (TFEB) on the promoter of ferritin heavy chain 1 (FTH1) were predicted by the online dataset JASPAR and confirmed by luciferase and chromatin immunoprecipitation (ChIP) assays. Cell death was determined using propidium iodide (PI) and TdT-mediated dUTP nick-end labeling (TUNEL) staining. The results showed that PTPRC was significantly overexpressed in OS tissues and cells. PTPRC knockdown promoted the phosphorylation and nuclear translocation of TFEB. Moreover, PTPRC knockdown markedly promoted lysosome biogenesis and the accumulation of ferrous ion (Fe2+), whereas decreased the release of glutathione (GSH). Besides, PTPRC knockdown significantly promoted autophagy and downregulated mRNA expression of FTH1 and ferritin light chain (FTL). Additionally, TFEB transcriptionally inactivated FTH1. PTPRC knockdown significantly promoted the ferroptosis of OS cells, which was markedly alleviated by TFEB shRNA. Taken together, PTPRC knockdown-mediated TFEB phosphorylation and translocation dramatically promoted lysosome biogenesis, ferritinophagy, as well as the ferroptosis of OS cells via regulating FTH1/FTL signaling. Therefore, PTPRC/TFEB/FTH1 signaling may be a potential target for OS. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis is characterized by a burst of inflammation, the destruction of cartilage and the abundant release of inflammatory factors such as IL-1β. Thus, the effect of IL-1β on cartilage was examined in this study. IL-1β could cause lipid peroxidation and disturbances in iron metabolism by increasing the expression of NCOA4 and decreasing the expression of FTH, which also induced ferritinophagy. In addition, the expression of the key antioxidant proteins SLC7A11 and GPX4 was inhibited by IL-1β, resulting in ferroptosis in chondrocytes. Spermidine (SPD), a low-molecular-weight aliphatic nitrogen-containing compound that widely exists in animals, has been reported to be an antioxidant. In our study, we found that SPD could inhibit ferritinophagy and reverse the decrease in the expression of SLC7A11 and GPX4. Therefore, we uncovered one of the molecular mechanisms of cartilage destruction and inflammation and provide a potential polyamine for the treatment of RA. [ABSTRACT FROM AUTHOR]

Background: Following the announcement by the European Food Safety Authority that the food additive titanium dioxide (E 171) is unsafe for human consumption, and the subsequent ban by the European Commission, concerns have intensified over the potential risks E 171 poses to human vital organs. The liver is the main organ for food-grade nanoparticle metabolism. It is increasingly being found that epigenetic changes may play an important role in nanomaterial-induced hepatotoxicity. However, the profound effects of E 171 on the liver, especially at the epigenetic level, remain largely unknown. Methods: Mice were exposed orally to human-relevant doses of two types of E 171 mixed in diet for 28 and/or 84 days. Conventional toxicology and global DNA methylation analyses were performed to assess E 171-induced hepatotoxicity and epigenetic changes. Whole genome bisulfite sequencing and further ferroptosis protein detection were used to reveal E 171-induced changes in liver methylation profiles and toxic mechanisms. Results: Exposed to E 171 for 28 and/or 84 days resulted in reduced global DNA methylation and hydroxymethylation in the liver of mice. E 171 exposure for 84 days elicited inflammation and damage in the mouse liver, whereas 28-day exposure did not. Whole-genome DNA methylation sequencing disclosed substantial methylation alterations at the CG and non-CG sites of the liver DNA in mice exposed to E 171 for 84 days. Mechanistic analysis of the DNA methylation alterations indicated that ferroptosis contributed to the liver toxicity induced by E 171. E 171-induced DNA methylation changes triggered NCOA4-mediated ferritinophagy, attenuated the protein levels of GPX4, FTH1, and FTL in the liver, and thereby caused ferroptosis. Conclusions: Long-term oral exposure to E 171 triggers hepatotoxicity and induces methylation changes in both CG and non-CG sites of liver DNA. These epigenetic alterations activate ferroptosis in the liver through NCOA4-mediated ferritinophagy, highlighting the role of DNA methylation and ferroptosis in the potential toxicity caused by E 171 in vivo. [ABSTRACT FROM AUTHOR]

Objectives: This study aims to elucidate the role of Fe2+ overload in kainic acid (KA)‐induced excitotoxicity, investigate the involvement of ferritinophagy selective cargo receptor NCOA4 in the pathogenesis of excitotoxicity. Methods: Western blotting was used to detect the expression of FTH1, NCOA4, Lamp2, TfR, FPN, and DMT1 after KA stereotaxic injection into the unilateral striatum of mice. Colocalization of Fe2+ with lysosomes in KA‐treated primary cortical neurons was observed by using confocal microscopy. Desferrioxamine (DFO) was added to chelate free iron, a CCK8 kit was used to measure cell viability, and the Fe2+ levels were detected by FerroOrange. BODIPY C11 was used to determine intracellular lipid reactive oxygen species (ROS) levels, and the mRNA levels of PTGS2, a biomarker of ferroptosis, were measured by fluorescent quantitative PCR. 3‐Methyladenine (3‐MA) was employed to inhibit KA‐induced activation of autophagy, and changes in ferritinophagy‐related protein expression and the indicated biomarkers of ferroptosis were detected. Endogenous NCOA4 was knocked down by lentivirus transfection, and cell viability and intracellular Fe2+ levels were observed after KA treatment. Results: Western blot results showed that the expression of NCOA4, DMT1, and Lamp2 was significantly upregulated, while FTH1 was downregulated, but there were no significant changes in TfR and FPN. The fluorescence results indicated that KA enhanced the colocalization of free Fe2+ with lysosomes in neurons. DFO intervention could effectively rescue cell damage, reduce intracellular lipid peroxidation, and decrease the increased transcript levels of PTGS2 caused by KA. Pretreatment with 3‐MA effectively reversed KA‐induced ferritinophagy and ferroptosis. Endogenous interference with NCOA4 significantly improved cell viability and reduced intracellular free Fe2+ levels in KA‐treated cells. Conclusion: KA‐induced excitotoxicity activates ferritinophagy, and targeting ferritinophagy effectively inhibits downstream ferroptosis. Interference with NCOA4 effectively attenuates KA‐induced neuronal damage. This study provides a potential therapeutic target for excitotoxicity related disease conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: This study presents data on the immunohistochemical expression of key iron metabolism proteins in non-neoplastic and neoplastic canine testes. Iron is crucial for spermatogenesis, and its regulation in testicular cells is essential for normal function. This study confirms that Sertoli cells and Transferrin Receptor 1 (TfR1) play significant roles in iron uptake in dogs, aligning with findings in humans and mice. However, it highlights a unique expression of nuclear receptor coactivator 4 (NCOA4) in canine Sertoli cells, suggesting a specific role in iron recycling through ferritinophagy. Differences in iron metabolism were observed in various canine testicular tumors. Higher TfR1 and NCOA4 expressions were noted in Leydig cell tumors and diffuse seminomas, indicating a reliance on iron for tumor growth. The altered expression of iron-related proteins in tumors underscores their potential as therapeutic targets. Targeting TfR1 and utilizing iron-modulating therapies shows promise. Further research is needed to explore the therapeutic potential of modulating iron metabolism in canine testicular cancers. Iron is a key element in spermatogenesis; its metabolic pathway in the testis is strictly regulated. Alterations in iron metabolism are linked to various diseases, including cancer, and changes in iron metabolism-related proteins have been observed in multiple human, mouse and canine tumors. There is limited knowledge about iron metabolism in canine non-neoplastic and neoplastic testes. This study aimed to explore the immunohistochemical expression of molecules involved in iron uptake and storage [Transferrin Receptor 1 (TfR1), ferritin (FTH1), nuclear receptor coactivator 4 (NCOA4)] and PCNA in canine non-neoplastic and neoplastic testicular samples. Non-neoplastic testes showed moderate TfR1 expression in developing germ cells and Sertoli cells, high NCOA4 cytoplasmic immunostaining in the Sertoli cells and occasional cytoplasmic immunopositivity for FTH1 in the spermatogonia and Sertoli cells. In contrast, Leydig cell tumors (LCTs) and Diffuse Type Seminoma (DSEM) exhibited increased expression of TfR1, along with higher PCNA expression, suggesting a higher iron need for proliferation. Intratubular Type Seminoma (ITSEM) showed a higher FTH1 expression, indicating greater iron storage, while the increased NCOA4 expression in the LCTs and DSEM suggested ferritinophagy to release iron for proliferation. Sertoli cell tumors (SCTs) showed only NCOA4 expression. These preliminary findings highlight potential molecular targets for developing new anti-neoplastic treatments in canine testicular tumors. [ABSTRACT FROM AUTHOR]

The progressive loss of dopaminergic neurons in the midbrain is the hallmark of Parkinson's disease (PD). A newly emerging form of lytic cell death, ferroptosis, has been implicated in PD. However, it remains unclear in terms of PD-associated ferroptosis underlying causative genes and effective therapeutic approaches. This research explored the underlying mechanism of ferroptosis-related genes in PD. Here, Firstly, we found NOX1 associated with ferroptosis differently in PD patients by bioinformatics analysis. In vitro and in vivo models of PD were constructed to explore the underlying mechanism. q PCR, Western blot analysis, immunohistochemistry, immunofluorescence, Ferro orange, and BODIPY C11 were utilized to analyze the levels of ferroptosis. Transcriptomics sequencing was to investigate the downstream pathway and the analysis of immunoprecipitation to validate the upstream factor. In conclusion, NOX1 upregulation and activation of ferroptosis-related neurodegeneration, therefore, might be useful as a clinical therapeutic agent. [Display omitted] • This study demonstrated that NOX1 was associated with ferroptosis differently in PD patients by bioinformatics analysis. • NOX1 overexpression jeopardized the dopaminergic neurons. • NOX1 might activate the RUNX2/STK32A pathway which promotes ferritinophagy and further enhances ferroptosis. • FBXW7 promoted NOX1 degradation by ubiquitinating and ubiquitinating its K48-linked ubiquitin chains. [ABSTRACT FROM AUTHOR]

Abstract There are increasing concerns regarding the rapid expansion of polystyrene nanoplastics (PS-NPs), which could impact human health. Previous studies have shown that nanoplastics can be transferred from mothers to offspring through the placenta and breast milk, resulting in cognitive deficits in offspring. However, the neurotoxic effects of maternal exposure on offspring and its mechanisms remain unclear. In this study, PS-NPs (50 nm) were gavaged to female rats throughout gestation and lactation to establish an offspring exposure model to study the neurotoxicity and behavioral changes caused by PS-NPs on offspring. Neonatal rat hippocampal neuronal cells were used to investigate the pathways through which NPs induce neurodevelopmental toxicity in offspring rats, using iron inhibitors, autophagy inhibitors, reactive oxygen species (ROS) scroungers, P53 inhibitors, and NCOA4 inhibitors. We found that low PS-NPs dosages can cause ferroptosis in the hippocampus of the offspring, resulting in a decline in the cognitive, learning, and memory abilities of the offspring. PS-NPs induced NOCA4-mediated ferritinophagy and promoted ferroptosis by inciting ROS production to activate P53-mediated ferritinophagy. Furthermore, the levels of the antioxidant factors glutathione peroxidase 4 (GPX4) and glutathione (GSH), responsible for ferroptosis, were reduced. In summary, this study revealed that consumption of PS-NPs during gestation and lactation can cause ferroptosis and damage the hippocampus of offspring. Our results can serve as a basis for further research into the neurodevelopmental effects of nanoplastics in offspring. Graphical Abstract

Abstract Background Following the announcement by the European Food Safety Authority that the food additive titanium dioxide (E 171) is unsafe for human consumption, and the subsequent ban by the European Commission, concerns have intensified over the potential risks E 171 poses to human vital organs. The liver is the main organ for food-grade nanoparticle metabolism. It is increasingly being found that epigenetic changes may play an important role in nanomaterial-induced hepatotoxicity. However, the profound effects of E 171 on the liver, especially at the epigenetic level, remain largely unknown. Methods Mice were exposed orally to human-relevant doses of two types of E 171 mixed in diet for 28 and/or 84 days. Conventional toxicology and global DNA methylation analyses were performed to assess E 171-induced hepatotoxicity and epigenetic changes. Whole genome bisulfite sequencing and further ferroptosis protein detection were used to reveal E 171-induced changes in liver methylation profiles and toxic mechanisms. Results Exposed to E 171 for 28 and/or 84 days resulted in reduced global DNA methylation and hydroxymethylation in the liver of mice. E 171 exposure for 84 days elicited inflammation and damage in the mouse liver, whereas 28-day exposure did not. Whole-genome DNA methylation sequencing disclosed substantial methylation alterations at the CG and non-CG sites of the liver DNA in mice exposed to E 171 for 84 days. Mechanistic analysis of the DNA methylation alterations indicated that ferroptosis contributed to the liver toxicity induced by E 171. E 171-induced DNA methylation changes triggered NCOA4-mediated ferritinophagy, attenuated the protein levels of GPX4, FTH1, and FTL in the liver, and thereby caused ferroptosis. Conclusions Long-term oral exposure to E 171 triggers hepatotoxicity and induces methylation changes in both CG and non-CG sites of liver DNA. These epigenetic alterations activate ferroptosis in the liver through NCOA4-mediated ferritinophagy, highlighting the role of DNA methylation and ferroptosis in the potential toxicity caused by E 171 in vivo.

Abstract Acute kidney injury (AKI) is closely related to lysosomal dysfunction and ferroptosis in renal tubular epithelial cells (TECs), for which effective treatments are urgently needed. Although selenium nanoparticles (SeNPs) have emerged as promising candidates for AKI therapy, their underlying mechanisms have not been fully elucidated. Here, we investigated the effect of SeNPs on hypoxia/reoxygenation (H/R)-induced ferroptosis and lysosomal dysfunction in TECs in vitro and evaluated their efficacy in a murine model of ischemia/reperfusion (I/R)-AKI. We observed that H/R-induced ferroptosis was accompanied by lysosomal Fe2+ accumulation and dysfunction in TECs, which was ameliorated by SeNPs administration. Furthermore, SeNPs protected C57BL/6 mice against I/R-induced inflammation and ferroptosis. Mechanistically, we found that lysosomal Fe2+ accumulation and ferroptosis were associated with the excessive activation of NCOA4-mediated ferritinophagy, a process mitigated by SeNPs through the upregulation of X-box binding protein 1 (XBP1). Downregulation of XBP1 promoted ferritinophagy and partially counteracted the protective effects of SeNPs on ferroptosis inhibition in TECs. Overall, our findings revealed a novel role for SeNPs in modulating ferritinophagy, thereby improving lysosomal function and attenuating ferroptosis of TECs in I/R-AKI. These results provide evidence for the potential application of SeNPs as therapeutic agents for the prevention and treatment of AKI.

Primary ovarian insufficiency (POI) in younger women (under 40) manifests as irregular periods, high follicle-stimulating hormone (FSH), and low estradiol (E2), often triggered by chemotherapy. Though mesenchymal stem cell (MSC) therapy shows promise in treating POI, its exact mechanism remains unclear. This study reveals that human umbilical cord-derived MSCs (hUC-MSCs) can protect ovarian granulosa cells (GCs) from cyclophosphamide (CTX)-induced ferroptosis, a form of cell death driven by iron accumulation. CTX, commonly used to induce POI animal model, triggered ferroptosis in GCs, while hUC-MSCs treatment mitigated this effect, both in vivo and in vitro. Further investigations using ferroptosis and autophagy inhibitors suggest that hUC-MSCs act by suppressing ferroptosis in GCs. Interestingly, hUC-MSCs activate a protective antioxidant pathway in GCs via NRF2, a stress-response regulator. Overall, our findings suggest that hUC-MSCs improve ovarian function in CTX-induced POI by reducing ferroptosis in GCs. This study not only clarifies the mechanism behind the benefits of hUC-MSCs but also strengthens the case for their clinical use in treating POI. Additionally, it opens up a new avenue for protecting ovaries from chemotherapy-induced damage by regulating ferroptosis. [Display omitted] • hUC-MSCs effectively ameliorate ovarian dysfunction in CTX-induced POI model. • hUC-MSCs can reverse the iron overload and ferritinophagy in POI model and KGN cells. • hUC-MSCs can inhibit ferritinophagy-mediated ferroptosis in primary GCs of POI model and CTX-induced KGN cells. • NRF2 plays a key role in hUC-MSCs ameliorating ferritinophagy-mediated ferroptosis caused in POI model. [ABSTRACT FROM AUTHOR]

Cerebral ischemia–reperfusion injury (CIRI) is the second leading cause of death worldwide, posing a huge risk to human life and health. Therefore, investigating the pathogenesis underlying CIRI and developing effective treatments are essential. Ferroptosis is an iron-dependent mode of cell death, which is caused by disorders in iron metabolism and lipid peroxidation. Previous studies demonstrated that ferroptosis is also a form of autophagic cell death, and nuclear receptor coactivator 4(NCOA4) mediated ferritinophagy was found to regulate ferroptosis by interfering with iron metabolism. Ferritinophagy and ferroptosis are important pathogenic mechanisms in CIRI. This review mainly summarizes the link and regulation between ferritinophagy and ferroptosis and further discusses their mechanisms in CIRI. In addition, the potential treatment methods targeting ferritinophagy and ferroptosis for CIRI are presented, providing new ideas for the prevention and treatment of clinical CIRI in the future. [ABSTRACT FROM AUTHOR]

Background: Ferritinophagy-mediated ferroptosis plays a crucial role in fighting pathogen aggression. The long non-coding RNA Mir22hg is involved in the regulation of ferroptosis and aberrantly overexpression in lipopolysaccharide (LPS)-induced sepsis mice, but whether it regulates sepsis through ferritinophagy-mediated ferroptosis is unclear. Methods: Mir22hg was screened by bioinformatics analysis. Ferroptosis was assessed by assaying malondialdehyde (MDA), reactive oxygen species (ROS), and Fe2+ levels, glutathione (GSH) activity, as well as ferroptosis-related proteins GPX4 and SLC3A2 by using matched kits and performing western blot. Ferritinophagy was assessed by Lyso tracker staining and FerroOrange staining, immunofluorescence analysis of Ferritin and LC-3, and western blot analysis of LC-3II/I, p62, FTH1, and NCOA4. The bind of YTH domain containing 1 (YTHDC1) to Mir22hg or angiopoietin-like-4 (Angptl4) was verified by RNA pull-down and/or immunoprecipitation (RIP) assays. Results: Mir22hg silencing lightened ferroptosis and ferritinophagy in LPS-induced MLE-12 cells and sepsis mouse models, as presented by the downregulated MDA, ROS, Fe2+, NCOA4, and SLC3A2 levels, upregulated GPX4, GSH, and FTH1 levels, along with a decrease in autophagy. Mir22hg could bind to the m6A reader YTHDC1 without affecting its expression. Mechanistically, Mir22hg enhanced Angptl4 mRNA stability through recruiting the m6A reader YTHDC1. Furthermore, Angptl4 overexpression partly overturned Mir22hg inhibition-mediated effects on ferroptosis and ferritinophagy in LPS-induced MLE-12 cells. Conclusion: Mir22hg contributed to in ferritinophagy-mediated ferroptosis in sepsis via recruiting the m6A reader YTHDC1 and strengthening Angptl4 mRNA stability, highlighting that Mir22hg may be a potential target for sepsis treatment based on ferroptosis. [ABSTRACT FROM AUTHOR]

Ferroptosis, a necrotic, iron‐dependent controlled cell death mechanism, is distinguished by the development of lipid peroxides to fatal proportions. Malignant tumours, influenced by iron to promote fast development, are vulnerable to ferroptosis. Based upon mounting evidence it has been observed that ferroptosis may be immunogenic and hence may complement immunotherapies. A new approach includes iron oxide‐loaded nano‐vaccines (IONVs), having supremacy for the traits of the tumour microenvironment (TME) to deliver specific antigens through improving the immunostimulatory capacity by molecular disintegration and reversible covalent bonds that target the tumour cells and induce ferroptosis. Apart from IONVs, another newer approach to induce ferroptosis in tumour cells is through oncolytic virus (OVs). One such oncolytic virus is the Newcastle Disease Virus (NDV), which can only multiply in cancer cells through the p53‐SLC7A11‐GPX4 pathway that leads to elevated levels of lipid peroxide and intracellular reactive oxygen species leading to the induction of ferroptosis that induce ferritinophagy. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and excess molybdenum (Mo) are multiorgan toxic, but the detrimental impacts of Cd and/or Mo on poultry have not been fully clarified. Thence, a 16‐week sub‐chronic toxic experiment was executed with ducks to assess the toxicity of Cd and/or Mo. Our data substantiated that Cd and Mo coexposure evidently reduced GSH‐Px, GSH, T‐SOD, and CAT activities and elevated H2O2 and MDA concentrations in myocardium. What is more, the study suggested that Cd and Mo united exposure synergistically elevated Fe2+ content in myocardium and activated AMPK/mTOR axis, then induced ferroptosis by obviously upregulating ACSL4, PTGS2, and TFRC expression levels and downregulating SLC7A11, GPX4, FPN1, FTL1, and FTH1 expression levels. Additionally, Cd and Mo coexposure further caused excessive ferritinophagy by observably increasing autophagosomes, the colocalization of endogenous FTH1 and LC3, ATG5, ATG7, LC3II/LC3I, NCOA4, and FTH1 expression levels. In brief, this study for the first time substantiated that Cd and Mo united exposure synergistically induced ferroptosis and excess ferritinophagy by AMPK/mTOR axis, finally augmenting myocardium injure in ducks, which will offer an additional view on united toxicity between two heavy metals on poultry. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is a common and highly lethal form of brain cancer. Temozolomide (TMZ) is the primary chemotherapy used for GBM, but it has limited effectiveness, with about half of the patients developing resistance. Iron regulatory proteins (IRPs) modulate genes involved in iron metabolism, while the nuclear receptor coactivator 4 (NCOA4) controls iron metabolism through a process called ferritinophagy. In this study, we investigated whether boric acid increases chemosensitivity mediated by ferritinophagy via the NCOA4 and IRP2 signaling pathways in TMZ-resistant GBM cells. First, we generated TMZ-resistant GBM cells (A172-R and T98G-R cells). Next, we investigated the effects of boric acid on cell viability, proliferation, cell cycle, and cell morphology in these cells. Additionally, following boric acid treatment, we analyzed the expression and protein levels of various biochemical markers in these cells. Boric acid treatment in A172-R and T98G-R cells suppressed cell viability and proliferation, arrested these cells in the G1/G0 cell cycle, and induced morphological differences. Boric acid increased NCOA4, IRP2, iron, and malondialdehyde (MDA) levels in A172-R and T98G-R cells, while glutathione (GSH) and glutathione peroxidase 4 (GPx4) levels decreased. Moreover, boric acid treatment increased intracellular iron levels and lipid peroxidation by inducing NCOA4 and IRP2 expression levels in TMZ-resistant cells. According to our results, boric acid may regulate chemosensitivity in A172-R and T98G-R cells mediated by NCOA4 and IRP2. In conclusion, the manipulative effects of boric acid on the ferritinophagy pathway hold the potential to sensitize TMZ-resistant GBM cells to chemotherapy. [ABSTRACT FROM AUTHOR]

Premature ovarian insufficiency (POI) is defined as the depletion of ovarian function before the age of 40 years. The global prevalence of POI is 3.5%. To date, genetic factors account for 23.5% of the etiology of POI. Herein, a previously uncharacterized pathogenic homozygous variant of the chromosome segregation–1–like gene (CSE1L) was identified in POI patients via targeted panel sequencing. It is reported that dysregulated iron metabolism is involved in many reproductive endocrine disorders; however, its precise role in POI remains obscure. In this study, we identified CSE1L as a potential candidate gene that plays an important role in maintaining iron homeostasis. Deficiency of CSE1L led to ferroptosis in human granulosa cells, which was confirmed by transmission electron microscopy. Mechanistically, coimmunoprecipitation identified the direct interaction between CSE1L and FoxO1. Inhibition of CSE1L led to the excessive accumulation of FoxO1 in the nucleus via nucleocytoplasmic transport. Then, FoxO1 bound to the promoter region of NCOA4 and promoted its transcription, which was verified by a chromatin immunoprecipitation assay. Moreover, inhibition of CSE1L in cumulus cell monolayer could impede oocyte maturation, which might be associated with oxidative stress. Consequently, our study first revealed that CSE1L participated in ferroptosis in human ovarian granulosa cells via nucleocytoplasmic transportation, which might be helpful in revealing the molecular mechanism of CSE1L in the development of POI. Importantly, these findings might provide new insights into the application of ferroptosis inhibitors in the treatment of POI. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is closely related to lysosomal dysfunction and ferroptosis in renal tubular epithelial cells (TECs), for which effective treatments are urgently needed. Although selenium nanoparticles (SeNPs) have emerged as promising candidates for AKI therapy, their underlying mechanisms have not been fully elucidated. Here, we investigated the effect of SeNPs on hypoxia/reoxygenation (H/R)-induced ferroptosis and lysosomal dysfunction in TECs in vitro and evaluated their efficacy in a murine model of ischemia/reperfusion (I/R)-AKI. We observed that H/R-induced ferroptosis was accompanied by lysosomal Fe2+ accumulation and dysfunction in TECs, which was ameliorated by SeNPs administration. Furthermore, SeNPs protected C57BL/6 mice against I/R-induced inflammation and ferroptosis. Mechanistically, we found that lysosomal Fe2+ accumulation and ferroptosis were associated with the excessive activation of NCOA4-mediated ferritinophagy, a process mitigated by SeNPs through the upregulation of X-box binding protein 1 (XBP1). Downregulation of XBP1 promoted ferritinophagy and partially counteracted the protective effects of SeNPs on ferroptosis inhibition in TECs. Overall, our findings revealed a novel role for SeNPs in modulating ferritinophagy, thereby improving lysosomal function and attenuating ferroptosis of TECs in I/R-AKI. These results provide evidence for the potential application of SeNPs as therapeutic agents for the prevention and treatment of AKI. [ABSTRACT FROM AUTHOR]

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

Ischemic stroke presents a global health challenge, necessitating an in-depth comprehension of its pathophysiology and therapeutic strategies. While reperfusion therapy salvages brain tissue, it also triggers detrimental cerebral ischemia-reperfusion injury (CIRI). In our investigation, we observed the activation of nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy in an oxygen-glucose deprivation/reoxygenation (OGD/R) model using HT22 cells (P < 0.05). This activation contributed to oxidative stress (P < 0.05), enhanced autophagy (P < 0.05) and cell death (P < 0.05) during CIRI. Silencing NCOA4 effectively mitigated OGD/R-induced damage (P < 0.05). These findings suggested that targeting NCOA4-mediated ferritinophagy held promise for preventing and treating CIRI. Subsequently, we substantiated the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway effectively regulated the NCOA4-mediated ferritinophagy, by applying the cGAS inhibitor RU.521 and performing NCOA4 overexpression (P < 0.05). Suppressing the cGAS-STING pathway efficiently curtailed ferritinophagy (P < 0.05), oxidative stress (P < 0.05), and cell damage (P < 0.05) of CIRI, while NCOA4 overexpression could alleviate this effect (P < 0.05). Finally, we elucidated the specific molecular mechanism underlying the protective effect of the iron chelator deferoxamine (DFO) on CIRI. Our findings revealed that DFO alleviated hypoxia-reoxygenation injury in HT22 cells through inhibiting NCOA4-mediated ferritinophagy and reducing ferrous ion levels (P < 0.05). However, the protective effects of DFO were counteracted by cGAS overexpression (P < 0.05). In summary, our results indicated that the activation of the cGAS-STING pathway intensified cerebral damage during CIRI by inducing NCOA4-mediated ferritinophagy. Administering the iron chelator DFO effectively attenuated NCOA4-induced ferritinophagy, thereby alleviating CIRI. Nevertheless, the role of the cGAS-STING pathway in CIRI regulation likely involves intricate mechanisms, necessitating further validation in subsequent investigations. [ABSTRACT FROM AUTHOR]

Propofol is a clinically common intravenous general anesthetic and is widely used for anesthesia induction, maintenance and intensive care unit (ICU) sedation in children. Hypoxemia is a common perioperative complication. In clinical work, we found that children with hypoxemia who received propofol anesthesia experienced significant postoperative cognitive changes. To explore the causes of this phenomenon, we conducted the study. In this study, our in vivo experiments found that immature rats exposed to hypoxia combined with propofol (HCWP) could develop cognitive impairment. We performed the RNA-seq analysis of its hippocampal tissues and found that autophagy and ferroptosis may play a role in our model. Next, we verified the participation of the two modes of death by detecting the expression of autophagy-related indexes Sequestosome 1 (SQSTM1) and Beclin1, and ferroptosis-related indicators Fe2+, reactive oxygen species (ROS) and glutathione peroxidase 4 (GPX4). Meanwhile, we found that ferrostatin-1 (Fer-1), an inhibitor of ferroptosis, could improve cognitive impairment in immature rats caused by HCWP. In addition, we found that nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy, which acted as a key junction between autophagy and ferroptosis, was also involved. Finally, our in vitro experiments concluded that autophagy activation was an upstream factor in HCWP-induced hippocampus ferroptosis through the intervention of autophagy inhibitor 3-methyladenine (3-MA). Our study was expected to provide an attractive therapeutic target for cognitive impairment that occurred after HCWP exposures. [ABSTRACT FROM AUTHOR]

Recently, we characterized the ferroptotic phenotype in the liver of diabetic mice and revealed nuclear factor (erythroid‐derived‐2)‐related factor 2 (Nrf2) inactivation as an integral part of hepatic injury. Here, we aim to investigate whether sulforaphane, an Nrf2 activator and antioxidant, prevents diabetes‐induced hepatic ferroptosis and the mechanisms involved. Male C57BL/6 mice were divided into four groups: control (vehicle‐treated), diabetic (streptozotocin‐induced; 40 mg/kg, from Days 1 to 5), diabetic sulforaphane‐treated (2.5 mg/kg from Days 1 to 42) and non‐diabetic sulforaphane‐treated group (2.5 mg/kg from Days 1 to 42). Results showed that diabetes‐induced inactivation of Nrf2 and decreased expression of its downstream antiferroptotic molecules critical for antioxidative defense (catalase, superoxide dismutases, thioredoxin reductase), iron metabolism (ferritin heavy chain (FTH1), ferroportin 1), glutathione (GSH) synthesis (cystine‐glutamate antiporter system, cystathionase, glutamate‐cysteine ligase catalitic subunit, glutamate‐cysteine ligase modifier subunit, glutathione synthetase), and GSH recycling ‐ glutathione reductase (GR) were reversed/increased by sulforaphane treatment. In addition, we found that the ferroptotic phenotype in diabetic liver is associated with increased ferritinophagy and decreased FTH1 immunopositivity. The antiferroptotic effect of sulforaphane was further evidenced through the increased level of GSH, decreased accumulation of labile iron and lipid peroxides (4‐hydroxy‐2‐nonenal, lipofuscin), decreased ferritinophagy and liver damage (decreased fibrosis, alanine aminotransferase, and aspartate aminotransferase). Finally, diabetes‐induced increase in serum glucose and triglyceride level was significantly reduced by sulforaphane. Regardless of the fact that this study is limited by the use of one model of experimentally induced diabetes, the results obtained demonstrate for the first time that sulforaphane prevents diabetes‐induced hepatic ferroptosis in vivo through the activation of Nrf2 signaling pathways. This nominates sulforaphane as a promising phytopharmaceutical for the prevention/alleviation of ferroptosis in diabetes‐related pathologies. [ABSTRACT FROM AUTHOR]

Gastrointestinal cancer is a significant global health burden, necessitating the development of novel therapeutic strategies. Emerging evidence has highlighted the potential of targeting ferritinophagy as a promising approach for the treatment of gastrointestinal cancer. Ferritinophagy is a form of selective autophagy that is mediated by the nuclear receptor coactivator 4 (NCOA4). This process plays a crucial role in regulating cellular iron homeostasis and has been implicated in various pathological conditions, including cancer. This review discusses the molecular mechanisms underlying ferritinophagy and its relevance to gastrointestinal cancer. Furthermore, we highlight the potential therapeutic implications of targeting ferritinophagy in gastrointestinal cancer. Several approaches have been proposed to modulate ferritinophagy, including small molecule inhibitors and immunotherapeutic strategies. We discuss the advantages and challenges associated with these therapeutic interventions and provide insights into their potential clinical applications. [ABSTRACT FROM AUTHOR]

Objective: To assess the potential of ferroptosis and ferritinophagy in migraine pathogenesis. Background: Ferroptosis and ferritinophagy are related to increased cellular iron concentration and have been associated with the pathogenesis of several neurological disorders, but their potential in migraine pathogenesis has not been explored. Increased iron deposits in some deep brain areas, mainly periaqueductal gray (PAG), are reported in migraine and they have been associated with the disease severity and chronification as well as poor response to antimigraine drugs. Results: Iron deposits may interfere with antinociceptive signaling in the neuronal network in the brain areas affected by migraine, but their mechanistic role is unclear. Independently of the location, increased iron concentration may be related to ferroptosis and ferritinophagy in the cell. Therefore, both phenomena may be related to increased iron deposits in migraine. It is unclear whether these deposits are the reason, consequence, or just a correlate of migraine. Still, due to migraine-related elevated levels of iron, which is a prerequisite of ferroptosis and ferritinophagy, the potential of both phenomena in migraine should be explored. If the iron deposits matter in migraine pathogenesis, they should be mechanically linked with the clinical picture of the disease. As iron is an exogenous essential trace element, it is provided to the human body solely with diet or supplements. Therefore, exploring the role of iron in migraine pathogenesis may help to determine the potential role of ironrich/poor dietary products as migraine triggers or relievers. Conclusion: Ferroptosis and ferritinophagy may be related to migraine pathogenesis through iron deposits in the deep areas of the brain. [ABSTRACT FROM AUTHOR]

Cisplatin-induced acute kidney injury (AKI) increases the patient mortality dramatically and results in an unfavorable prognosis. A strong correlation between AKI and ferroptosis, which is a notable type of programmed cell death, was found in recent studies. Myricitrin is a natural flavonoid compound with diverse pharmacological properties. To investigate the protective effect of myricitrin against cisplatin induced human tubular epithelium (HK-2) cell injury and the underlying anti-ferroptic mechanism by this study. Firstly, a pharmacology network analysis was proposed to explore the myricitrin’s effect. HK-2 cells were employed for in vitro experiments. Ferroptosis was detected by cell viability, quantification of iron, malondialdehyde, glutathione, lipid peroxidation fluorescence, and glutathione peroxidase (GPX4) expression. Ferritinophagy was detected by related protein expression (NCOA4, FTH, LC3II/I, and SQSTM1). In our study, GO enrichment presented that myricitrin might be effective in eliminating ferroptosis. The phenomenon of ferroptosis regulated by ferritinophagy was observed in cisplatin-activated HK-2 cells. Meanwhile, pretreatment with myricitrin significantly rescued HK-2 cells from cell death, reduced iron overload and lipid peroxidation biomarkers, and improved GPX4 expression. In addition, myricitrin downregulated the expression of LC3II/LC3I and NCOA4 and elevated the expression of FTH and SQTM. Furthermore, myricitrin inhibited ROS production and preserved mitochondrial function with a lower percentage of green JC-1 monomers. However, the protection could be reserved by the inducer of ferritinophagy rapamycin. Mechanically, the Hub genes analysis reveals that AKT and NF-κB are indispensable mediators in the anti-ferroptic process. In conclusion, myricitrin ameliorates cisplatin induced HK-2 cells damage by attenuating ferritinophagy mediated ferroptosis. [ABSTRACT FROM AUTHOR]

Macroautophagy/autophagy is a complex degradation process with a dual role in cell death that is influenced by the cell types that are involved and the stressors they are exposed to. Ferroptosis is an iron-dependent oxidative form of cell death characterized by unrestricted lipid peroxidation in the context of heterogeneous and plastic mechanisms. Recent studies have shed light on the involvement of specific types of autophagy (e.g. ferritinophagy, lipophagy, and clockophagy) in initiating or executing ferroptotic cell death through the selective degradation of anti-injury proteins or organelles. Conversely, other forms of selective autophagy (e.g. reticulophagy and lysophagy) enhance the cellular defense against ferroptotic damage. Dysregulated autophagy-dependent ferroptosis has implications for a diverse range of pathological conditions. This review aims to present an updated definition of autophagy-dependent ferroptosis, discuss influential substrates and receptors, outline experimental methods, and propose guidelines for interpreting the results. Abbreviation: 3-MA:3-methyladenine; 4HNE: 4-hydroxynonenal; ACD: accidentalcell death; ADF: autophagy-dependentferroptosis; ARE: antioxidant response element; BH2:dihydrobiopterin; BH4: tetrahydrobiopterin; BMDMs: bonemarrow-derived macrophages; CMA: chaperone-mediated autophagy; CQ:chloroquine; DAMPs: danger/damage-associated molecular patterns; EMT,epithelial-mesenchymal transition; EPR: electronparamagnetic resonance; ER, endoplasmic reticulum; FRET: Försterresonance energy transfer; GFP: green fluorescent protein;GSH: glutathione;IF: immunofluorescence; IHC: immunohistochemistry; IOP, intraocularpressure; IRI: ischemia-reperfusion injury; LAA: linoleamide alkyne;MDA: malondialdehyde; PGSK: Phen Green™ SK;RCD: regulatedcell death; PUFAs: polyunsaturated fatty acids; RFP: red fluorescentprotein;ROS: reactive oxygen species; TBA: thiobarbituricacid; TBARS: thiobarbituric acid reactive substances; TEM:transmission electron microscopy. [ABSTRACT FROM AUTHOR]

Cisplatin is a widely used antineoplastic drug for treating various types of cancers. However, it can cause severe side effects, such as bilateral and irreversible hearing loss, which significantly impacts quality of life. Ferroptosis, an iron-dependent form of programmed cell death, has been implicated in the pathogenesis of cisplatin-induced ototoxicity. Here, we investigated the effects of nuciferine, a natural active ingredient isolated from lotus species, on the ferroptosis of cochlear hair cells. Firstly, our results demonstrated that nuciferine can protect hair cells against RSL3-induced and cisplatin-induced damage. Secondly, nuciferine treatment reduced ferrous iron (Fe2+) overload in cochlear hair cells via inhibiting NCOA4-mediated ferritinophagy. Inhibition of ferritinophagy by knocking down Ncoa4 alleviated cisplatin-induced ototoxicity. Importantly, nuciferine treatment mitigated cochlear hair cell loss and damage to ribbon synapse, and improved mouse hearing function in an acute cisplatin-induced hearing loss model. Our findings highlight the role of NCOA4-mediated ferritinophagy in the pathogenesis of cisplatin-induced ototoxicity and provide evidence for nuciferine as a promising protective agent for treating cisplatin-induced hearing loss. [ABSTRACT FROM AUTHOR]

BackgroundCDGSH iron-sulfur domain 2 (CISD2), an iron-sulfur protein with a [2Fe-2S] cluster, plays a pivotal role in the progression of various cancers, including Diffuse Large B-cell Lymphoma (DLBCL). However, the mechanisms by which CISD2 regulates the occurrence and development of DLBCL remain to be fully elucidated.MethodsThe potential role of CISD2 as a predictive marker in DLBCL patients treated with the R-CHOP regimen was investigated through bioinformatics analysis and clinical cohort studies. DLBCL cell lines (SUDHL-4 and HBL-1) were employed in this research. Adenoviral (AV) plasmids were used to either silence or overexpress CISD2 in these DLBCL cell lines. Additionally, the induction of ferroptosis in DLBCL cell lines was assessed. Various parameters, including cell proliferation, intracellular free iron levels, lipid peroxides, reactive oxygen species (ROS), and mitochondrial membrane potential (MMP), were measured. Furthermore, the expression of proteins associated with ferroptosis and ferritinophagy was analyzed. Drug-resistant DLBCL cell lines were developed by gradually increasing doxorubicin (DOX) concentration over 6 months. The biological role of CISD2 in these drug-resistant DLBCL cell lines was subsequently assessed.ResultsElevated CISD2 levels were found to be associated with decreased sensitivity of DLBCL patients to the R-CHOP regimen, as indicated by bioinformatics and clinical cohort analysis. Silencing CISD2 significantly reduced cell proliferation, increased iron accumulation, depleted glutathione (GSH), and elevated malondialdehyde (MDA) levels, alongside the accumulation of ROS and increased MMP. Additionally, BECN1 and NCOA4 expressions were upregulated, while p62, FTH1, and GPX4 expressions were downregulated. Conversely, overexpression of CISD2 reversed these effects. Treatment of DLBCL cell lines with Erastin led to decreased CISD2 levels. Notably, in drug-resistant DLBCL cell lines, CISD2 knockdown promoted ferroptosis and ferritinophagy, restoring sensitivity to DOX and enhancing the efficacy of Erastin treatment.ConclusionOur findings suggest that CISD2 may play a role in the drug resistance observed in DLBCL patients. Inhibition of CISD2 could enhance ferroptosis and ferritinophagy, potentially improving the sensitivity of DLBCL cells to DOX treatment.

Acute kidney injury (AKI) is primarily caused by renal ischemia-reperfusion injury (IRI), which is one of the most prevalent triggers. Currently, preventive and therapeutic measures remain limited. Ferroptosis plays a significant role in the pathophysiological process of IRI-induced AKI and is considered a key target for improving its outcomes. Silibinin, a polyphenolic flavonoid, possesses diverse pharmacological properties and is widely used as an effective therapeutic agent for liver diseases. Recent studies have reported that silibinin may improves kidney diseases, though the underlying mechanism remain unclear. In this study, we investigated whether silibinin protects against IRI-induced AKI and explored its mechanism of action. Our findings indicated that pretreatment with silibinin alleviated renal dysfunction, pathological damage, and inflammation in IRI-AKI mice. Furthermore, the results demonstrated that silibinin inhibited ferroptosis both in vivo and in vitro. Proteome microarrays were used to identify silibinin's target, and our results revealed that silibinin binds to FTH1. This binding affinity was confirmed through molecular docking, SPRi, CETSA, and DARTS. Additionally, co-IP assays demonstrated that silibinin disrupted the NCOA4-FTH1 interaction, inhibiting ferritinophagy. Finally, the inhibitory effects of silibinin on ferroptosis were reversed by knocking down FTH1 in vitro. In conclusion, our study shows that silibinin effectively alleviates AKI by targeting FTH1 to reduce ferroptosis, suggesting that silibinin could be developed as a potential therapeutic agent for managing and treating AKI.

Abstract Mammalian cochlea spiral ganglion neurons (SGNs) are crucial for sound transmission, they can be damaged by chemotherapy drug cisplatin and lead to irreversible sensorineural hearing loss (SNHL), while such damage can also render cochlear implants ineffective. However, the mechanisms underlying cisplatin‐induced SGNs damage and subsequent SNHL are still under debate and there is no currently effective clinical treatment. Here, this study demonstrates that ferroptosis is triggered in SGNs following exposure to cisplatin. Inhibiting ferroptosis protects against cisplatin‐induced SGNs damage and hearing loss, while inducing ferroptosis intensifies these effects. Furthermore, cisplatin prompts nuclear receptor coactivator 4 (NCOA4)‐mediated ferritinophagy in SGNs, while knocking down NCOA4 mitigates cisplatin‐induced ferroptosis and hearing loss. Notably, the upstream regulator of NCOA4 is identified and transcription factor forkhead box O1 (FOXO1) is shown to directly suppress NCOA4 expression in SGNs. The knocking down of FOXO1 amplifies NCOA4‐mediated ferritinophagy, increases ferroptosis and lipid peroxidation, while disrupting the interaction between FOXO1 and NCOA4 in NCOA4 knock out mice prevents the cisplatin‐induced SGN ferroptosis and hearing loss. Collectively, this study highlights the critical role of the FOXO1‐NCOA4 axis in regulating ferritinophagy and ferroptosis in cisplatin‐induced SGNs damage, offering promising therapeutic targets for SNHL mitigation.

Nephrotoxicity is a common complication that limits the clinical utility of cisplatin. Ferroptosis is an iron-dependent necrotic cell death program that is mediated by phospholipid peroxidation. The molecular mechanisms that disrupt iron homeostasis and lead to ferroptosis are yet to be elucidated. In this study, we aimed to investigate the involvement of nuclear receptor coactivator 4 (NCOA4), a selective cargo receptor that mediates ferroptosis and autophagic degradation of ferritin in nephrotoxicity. Adult male Sprague-Dawley rats were randomly-assigned to four groups: control group, cisplatin (Cis)-treated group, deferiprone (DEF)-treated group, and Cis+DEF co-treated group. Serum, urine, and kidneys were isolated to perform biochemical, morphometric, and immunohistochemical analysis. Iron accumulation was found to predispose to ferroptotic damage of the renal tubular cells. Treatment with deferiprone highlights the role of ferroptosis in nephrotoxicity. Upregulation of NCOA4 in parallel with low ferritin level in renal tissue seems to participate in iron-induced ferroptosis. This study indicated that ferroptosis may participate in cisplatin-induced tubular cell death and nephrotoxicity through iron-mediated lipid peroxidation. Iron dyshomeostasis could be attributed to NCOA4-mediated ferritin degradation.

Acute kidney injury (AKI) is a significant issue in public health, displaying a high occurrence rate and mortality rate. Ferroptosis, a form of programmed cell death (PCD), is characterized by iron accumulation and intensified lipid peroxidation. Recent studies have demonstrated the pivotal significance of ferroptosis in AKI caused by diverse stimuli, including ischemia-reperfusion injury (IRI), sepsis and toxins. Autophagy, a multistep process that targets damaged organelles and macromolecules for degradation and recycling, also plays an essential role in AKI. Previous research has demonstrated that autophagy deletion in proximal tubules could aggravate tubular injury and renal function loss, indicating the protective function of autophagy in AKI. Consequently, finding ways to stimulate autophagy has become a crucial therapeutic strategy. The recent discovery of the role of selective autophagy in influencing ferroptosis has identified new therapeutic targets for AKI and has highlighted the importance of understanding the cross-talk between autophagy and ferroptosis. This study aims to provide an overview of the signaling pathways involved in ferroptosis and autophagy, focusing on the mechanisms and functions of selective autophagy and autophagy-dependent ferroptosis. We hope to establish a foundation for future investigations into the interaction between autophagy and ferroptosis in AKI as well as other diseases.

ABSTRACTOxidative stress and neuronal dysfunction caused by intracerebral haemorrhage (ICH) can lead to secondary injury. The m6A modification has been implicated in the progression of ICH. This study aimed to investigate the role of the m6A reader YTHDC2 in ICH-induced secondary injury. ICH models were established in rats using autologous blood injection, and neuronal cell models were induced with Hemin. Experiments were conducted to overexpress YTH domain containing 2 (YTHDC2) and examine its effects on neuronal dysfunction, brain injury, and neuronal ferritinophagy. RIP-qPCR and METTL3 silencing were performed to investigate the regulation of YTHDC2 on nuclear receptor coactivator 4 (NCOA4). Finally, NCOA4 overexpression was used to validate the regulatory mechanism of YTHDC2 in ICH. The study found that YTHDC2 expression was significantly downregulated in the brain tissues of ICH rats. However, YTHDC2 overexpression improved neuronal dysfunction and reduced brain water content and neuronal death after ICH. Additionally, it reduced levels of ROS, NCOA4, PTGS2, and ATG5 in the brain tissues of ICH rats, while increasing levels of FTH and FTL. YTHDC2 overexpression also decreased levels of MDA and Fe2+ in the serum, while promoting GSH synthesis. In neuronal cells, YTHDC2 overexpression alleviated Hemin-induced injury, which was reversed by Erastin. Mechanistically, YTHDC2-mediated m6A modification destabilized NCOA4 mRNA, thereby reducing ferritinophagy and alleviating secondary injury after ICH. However, the effects of YTHDC2 were counteracted by NCOA4 overexpression. Overall, YTHDC2 plays a protective role in ICH-induced secondary injury by regulating NCOA4-mediated ferritinophagy.

Age-associated decreases in follicle number and oocyte quality result in a decline in female fertility, which is associated with increased infertility. Granulosa cells play a major role in oocyte development and maturation both in vivo and in vitro. However, it is unclear whether a reduction in cryptochrome 1 (Cry1) expression contributes to granulosa cell senescence, and further exploration is needed to understand the underlying mechanisms. In this study, we investigated the role of Cry1, a core component of the molecular circadian clock, in the regulation of senescence in ovarian granulosa cells. Western blotting and qRT-PCR showed that Cry1 expression was downregulated in aged human ovarian granulosa cells and was correlated with age and anti-Müllerian hormone (AMH) levels. RNA-seq analysis suggested that ferritinophagy was increased after Cry1 knockdown in KGN cells. MDA, iron, and reactive oxygen species (ROS) assays were used to detect cellular ferritinophagy levels. Ferroptosis inhibitors, iron chelators, autophagy inhibitors, and nuclear receptor coactivator 4 (NCOA4) knockdown alleviated KGN cell senescence induced by Cry1 knockdown. Immunofluorescence, immunoprecipitation, and ubiquitination assays indicated that Cry1 affected NCOA4 ubiquitination and degradation through HERC2, thereby affecting NCOA4-mediated ferritinophagy and causing granulosa cell senescence. KL201, a Cry1 stabilizer, enhanced ovarian function in naturally aged mice by reducing ferritinophagy. Our study reveals the potential mechanisms of action of Cry1 during ovarian aging and provides new insights for the clinical treatment of age-related fertility decline. A proposed molecular model of Cry1 in regulating senescence of human granulosa cells. Cry1 depletion reduced the expression of the E3 ubiquitin ligase HERC2, which reduced the ubiquitination and degradation of NCOA4, thereby promoting ferritinophagy and inducing granulosa cell senescence. [Display omitted] • Cry1 expression is downregulated in aged human ovarian granulosa cells. • Cry1 induces KGN cell senescence through NCOA4-mediated ferritinophagy. • Cry1 affects NCOA4 ubiquitination and degradation through HERC2. • Cry1 stabilizer KL201 enhances ovarian function by reducing ferritinophagy in middle-aged mice. [ABSTRACT FROM AUTHOR]

Cisplatin‐induced acute kidney injury (AKI) is commonly seen in the clinical practice, and ferroptosis, a type of non‐apoptotic cell death, plays a pivotal role in it. Previous studies suggested that protein arginine methyltransferase 4 (PRMT4) was incorporated in various bioprocesses, but its role in renal injuries has not been investigated. Our present study showed that PRMT4 was highly expressed in renal proximal tubular cells, and it was downregulated in cisplatin‐induced AKI. Besides, genetic disruption of PRMT4 exacerbated, while its overexpression attenuated, cisplatin‐induced redox injuries in renal proximal epithelia. Mechanistically, our work showed that PRMT4 interacted with NCOA4 to inhibit ferritinophagy, a type of selective autophagy favoring lipid peroxidation to accelerate ferroptosis. Taken together, our study demonstrated that PRMT4 interacted with NCOA4 to attenuate ferroptosis in cisplatin‐induced AKI, suggesting that PRMT4 might present as a new therapeutic target for cisplatin‐related nephropathy. [ABSTRACT FROM AUTHOR]

Copper (Cu) is one of the most significant trace elements in the body, but it is also a widespread environmental toxicant health. Ferroptosis is a newly identified programmed cell death, which involves various heavy metal–induced organ toxicity. Nevertheless, the role of ferroptosis in Cu-induced hepatotoxicity remains poorly understood. In this study, we found that 330 mg/kg Cu could disrupt the liver structure and cause characteristic morphological changes in mitochondria associated with ferroptosis. Additionally, Cu treatment increased MDA (malondialdehyde) and LPO (lipid peroxide) production while reducing GSH (reduced glutathione) content and GCL (glutamate cysteine ligase) activity. However, it is noticeable that there were no appreciable differences in liver iron content and key indicators of iron metabolism. Meanwhile, our further investigation found that 330 mg/kg Cu-exposure changed multiple ferroptosis-related indicators in chicken livers, including inhibition of the expression of SLC7A11, GPX4, FSP1, and COQ10B, whereas enhances the levels of ACLS4, LPCAT3, and LOXHD1. Furthermore, the changes in the expression of NCOA4, TXNIP, and Nrf2/Keap1 signaling pathway–related genes and proteins also further confirmed 330 mg/kg Cu exposure-induced ferroptosis. In conclusion, our results indicated that ferroptosis may play essential roles in Cu overload–induced liver damage, which offered new insights into the pathogenesis of Cu-induced hepatotoxicity. [ABSTRACT FROM AUTHOR]

Reactive species are involved in various aspects of neoplastic diseases, including carcinogenesis, cancer-specific metabolism and therapeutics. Non-thermal plasma (NTP) can directly provide reactive species, by integrating atmospheric and interjacent molecules as substrates, to represent a handy strategy to load oxidative stress in situ. NTP causes apoptosis and/or ferroptosis specifically in cancer cells of various types. Plasma-activated Ringer's lactate (PAL) is another modality at the preclinical stage as cancer therapeutics, based on more stable reactive species. PAL specifically kills malignant mesothelioma (MM) cells, employing lysosomal ·NO as a switch from autophagy to ferroptosis. However, the entire molecular mechanisms have not been elucidated yet. Here we studied cytosolic iron regulations in MM and other cancer cells in response to PAL exposure. We discovered that cells with higher catalytic Fe(II) are more susceptible to PAL-induced ferroptosis. PAL caused a cytosolic catalytic Fe(II)-associated pathology through iron chaperones, poly (rC)-binding proteins (PCBP)1/2, inducing a disturbance in glutathione-regulated iron homeostasis. PCBP1/NCOA4-mediated ferritinophagy started at a later phase, further increasing cytosolic catalytic Fe(II), ending in ferroptosis. In contrast, PCBP2 after PAL exposure contributed to iron loading to mitochondria, leading to mitochondrial dysfunction. Therapeutic effect of PAL was successfully applied to an orthotopic MM xenograft model in mice. In conclusion, PAL can selectively sensitize MM cells to ferroptosis by remodeling cytoplasmic iron homeostasis, where glutathione and PCBPs play distinct roles, resulting in lethal ferritinophagy and mitochondrial dysfunction. Our findings indicate the clinical application of PAL as a ferroptosis-inducer and the potential of PCBPs as novel targets in cancer therapeutics. [Display omitted] • Cells with higher catalytic Fe(II) are more susceptible to PAL. • GSH coordinates with elevated cytosolic Fe(II) as catalytic part of labile iron pool. • PAL caused a cytosolic catalytic Fe(II)-associated pathology through iron chaperones. • PCBP2 carried excess cytosolic catalytic Fe(II) to mitochondria, causing ferroptosis. • Effect of PAL was demonstrated in an orthotopic MM xenograft model of mice. [ABSTRACT FROM AUTHOR]

Background and Aim: Hepatotoxicity is a well‐defined reaction to methotrexate (MTX), a drug commonly used for the treatment of rheumatoid arthritis and various tumours. We sought to elucidate the mechanism underlying MTX‐induced hepatotoxicity and establish a potentially effective intervention strategy. Methods: We administered MTX to liver cells and mice and assessed hepatotoxicity by cell viability assay and hepatic pathological changes. We determined ferroptosis and ferritinophagy by detecting ferroptosis‐related markers and autophagic degradation of ferritin heavy chain 1 (FTH1). Results: We have shown that hepatocytes treated with MTX undergo ferroptosis, and this process can be attenuated by ferroptosis inhibitors. Interestingly, NCOA4‐mediated ferritinophagy was found to be involved in MTX‐induced ferroptosis, which was demonstrated by the relief of ferroptosis through the inhibition of autophagy or knockdown of Ncoa4. Furthermore, MTX treatment resulted in the elevation of high‐mobility group box 1 (HMGB1) expression. The depletion of Hmgb1 in hepatocytes considerably alleviated MTX‐induced hepatotoxicity by limiting autophagy and the subsequent autophagy‐dependent ferroptosis. It is noteworthy that glycyrrhizic acid (GA), a precise inhibitor of HMGB1, effectively suppressed autophagy, ferroptosis and hepatotoxicity caused by MTX. Conclusion: Our study shows the significant roles of autophagy‐dependent ferroptosis and HMGB1 in MTX‐induced hepatotoxicity. It emphasizes that the inhibition of ferritinophagy and HMGB1 may have potential as a therapeutic approach for preventing and treating MTX‐induced liver injury. [ABSTRACT FROM AUTHOR]

Objective: Ferroptosis is a reactive oxygen species (ROS)- and iron-dependent form of non-apoptotic cell death process. Previous studies have demonstrated that ferroptosis participates in the development of inflammatory arthritis. However, the role of ferroptosis in rheumatoid arthritis (RA) inflammatory hypoxic joints remains unclear. This study sought to explore the underlying mechanism of ferroptosis on lipopolysaccharide (LPS)-induced RA fibroblast-like synoviocytes (FLSs). Methods: FLSs, isolated from patients with RA, were treated with LPS and ferroptosis inducer (erastin and RSL-3), and ferroptosis inhibitor (Fer-1 and DFO), respectively. The cell viability was measured by CCK-8. The cell death was detected by flow cytometer. The proteins level were tested by Western blot. The cytosolic ROS and lipid peroxidation were determined using DCFH-DA and C11-BODIPY581/591 fluorescence probes, respectively. The small interfering RNA (siRNA) was used to knock down related proteins. The levels of malondialdehyde (MDA), 4-hydroxynonenal (4-HNE), iron, inflammatory cytokines (IL6 and IL8), and LDH were analyzed by commercial kits. Results: Ferroptosis was activated by LPS in RA FLS with increased cellular damage, ROS and lipid peroxidation, intracellular Fe and IL8, which can be further amplified by ferroptosis inducer (erastin and RSL-3) and inhibited by ferroptosis inhibitor (Fer-1 and DFO). Mechanistically, LPS triggered ferroptosis via NCOA4-mediated ferritinophagy in RA FLSs, and knockdown of NCOA4 strikingly prevent the process of ferroptosis. Intriguingly, LPS-induced RA FLSs became insensitive to ferroptosis and NCOA4-mediated ferritinophagy under hypoxia compared with normoxia. Knockdown of HIF-1α reverted ferroptosis and ferritinophagy evoking by LPS-induced RA FLSs inflammation under hypoxia. In addition, low dose of auranofin (AUR) induced re-sensitization of ferroptosis and ferritinophagy through inhibiting the expression of HIF-1α under hypoxia. Conclusions: NCOA4-mediated ferritinophagy was a key driver of ferroptosis in inflammatory RA FLSs. The suppression of NCOA4-mediated ferritinophagy protected RA FLSs from ferroptosis in LPS-induced inflammation under hypoxia. Targeting HIF-1α/NCOA4 and ferroptosis could be an effective and valuable therapeutic strategy for synovium hyperplasia in the patients with RA. [ABSTRACT FROM AUTHOR]

The discovery of the role of autophagy, particularly the selective form like ferritinophagy, in promoting cells to undergo ferroptosis has inspired us to investigate functional connections between diseases and cell death. Ferroptosis is a novel model of procedural cell death characterized by the accumulation of iron-dependent reactive oxygen species (ROS), mitochondrial dysfunction, and neuroinflammatory response. Based on ferroptosis, the study of ferritinophagy is particularly important. In recent years, extensive research has elucidated the role of ferroptosis and ferritinophagy in neurological diseases and anemia, suggesting their potential as therapeutic targets. Besides, the global emergence and rapid transmission of COVID-19, which is caused by SARS-CoV-2, represents a considerable risk to public health worldwide. The potential involvement of ferroptosis in the pathophysiology of brain injury associated with COVID-19 is still unclear. This review summarizes the pathophysiological changes of ferroptosis and ferritinophagy in neurological diseases, anemia, and COVID-19, and hypothesizes that ferritinophagy may be a potential mechanism of ferroptosis. Advancements in these fields will enhance our comprehension of methods to prevent and address neurological disorders, anemia, and COVID-19. [ABSTRACT FROM AUTHOR]