Ischemia-induced ACSL4 activation contributes to ferroptosis-mediated tissue injury in intestinal ischemia/reperfusion

Metal ions-induced programmed cell death: how does oxidative stress regulate cell death?

In recent years, the mechanisms of ferroptosis and cuproptosis, two novel modes of cell death, have been elucidated and have attracted much attention. Ferroptosis is dependent on the metabolic disruption of iron ions and lipid peroxidation, whereas cuproptosis is closely related to intracellular accumulation of copper ions, aggregation of lipoylated proteins and damage to FeS cluster proteins. In particular, oxidative stress plays an important role in both types of cell death. During ferroptosis, the central role of oxidative stress is reflected in the overproduction of reactive oxygen species (ROS) and lipid peroxidation of the cell membrane. Recent studies have revealed that ROS can propagate over long distances across cells in the form of trigger waves, triggering large-scale ferroptosis. In embryonic development, different regional redox states can limit the long-distance propagation of ferroptosis waves, which is critical for muscle remodeling and tissue formation during development. In cuproptosis, processes such as copper ions accumulation, tricarboxylic acid (TCA) cycle blockade, and reduced level of FeS cluster proteins are closely associated with oxidative stress. In addition, there is a close link between oxidative stress and death induced by other metal ions (Ca2+, Zn2+, etc.). In this paper, we review the role of oxidative stress in ferroptosis and cuproptosis and the related research progress to provide new ideas for understanding the mechanism of cell death and the occurrence and treatment of related diseases.

Gestational and lactational exposure to DEHP triggers ACSL4/TFR-mediated hippocampal neuronal ferroptosis via YAP activation: Implication for the neurocognitive disorders in male offspring

Di-(2-ethylhexyl) phthalate (DEHP) is one of the most extensively used phthalate and poses a public health concern. Perinatal exposure to DEHP has been shown to cause neurodevelopmental abnormalities and neurobehavioral disorders in offspring. However, the precise molecular mechanism has not yet been fully elucidated. In this study, pregnant C57BL/6 mice were exposed to DEHP from gestation to weaning. By RNA sequencing and animal experiments, ferroptosis has been identified as the key pathologic process contributing to DEHP-induced hippocampal injury in adult male offspring. In vitro results also showed that Ferrostatin-1 (Fer-1) effectively ameliorated Mono-(2-ethylhexyl) phthalate (MEHP) -induced cell survival via the inhibiting ferroptosis in HT22 cells. Consistently, we found that the expression of ACSL4 and TFR was significantly up-regulated in offspring hippocampi and MEHP-exposed HT22 neurons. However, silencing ACSL4 or knockdown TFR relieved MEHP-induced generation of lipid ROS and cellular iron accumulation, thereby blocking ferroptosis. Mechanistically, ACSL4/TFR-mediated ferroptosis seemed to be a Yes-associated protein (YAP) dependent via TEA domain transcription factor 4 in HT22 neurons. Importantly, treatment with Fer-1, rosiglitazone, and Deferoxamine effectively rescued DEHP-evoked cognitive decline in adult male offspring. Our findings certified that gestational and lactational exposure to DEHP provoked ACSL4/TFR-mediated hippocampal neuronal ferroptosis via YAP activation.

Combined exposure of polystyrene nanoplastics and silver nanoparticles exacerbating hepatotoxicity in zebrafish mediated by ferroptosis pathway through increased silver accumulation

Silver nanoparticles (AgNPs) are extensively utilized for their antibacterial properties, leading to their release into the environment and subsequent bioaccumulation and biomagnification within the food chain. Polystyrene nanoplastics (PSNPs), as emerging pollutants, act as carriers for contaminants and alter their transformation processes. However, the toxicological effects and underlying mechanisms associated with the coexistence of these pollutants remain largely unexplored. Herein, the hepatotoxic effects and underlying mechanisms of acute combined exposure to PSNPs and AgNPs were explored using zebrafish as a model organism. After exposed to PSNPs and AgNPs, the larvae (120 hours post-fertilization) exhibited lipid metabolism disorders, increased oxidative stress, hepatomegaly, and liver dysfunction, with these effects being more pronounced than those observed with AgNPs exposure alone. This increase in hepatic toxicity may be due to the enhanced accumulation of AgNPs under combined exposure. Mechanistic investigations revealed that co-exposure led to a significant elevation in malondialdehyde and Fe2 + levels, a loss of mitochondrial cristae and a decrease in membrane potential, along with the abnormal expression of ferroptosis-related genes, which are hallmark indicators of ferroptosis. Furthermore, the introduction of the ferroptosis inhibitor deferoxamine alleviated all observed hepatotoxic phenotypes, thereby confirming that PS+AgNPs co-exposure induced liver injury through the ferroptosis pathway.

Natural products and ferroptosis: A novel approach for heart failure management

BACKGROUND

The discovery of ferroptosis has brought a revolutionary breakthrough in heart failure treatment, and natural products, as a significant source of drug discovery, are gradually demonstrating their extraordinary potential in regulating ferroptosis and alleviating heart failure symptoms. In addition to chemically synthesized small molecule compounds, natural products have attracted attention as an important source for discovering compounds that target ferroptosis in treating heart failure.

PURPOSE

Systematically summarize and analyze the research progress on improving heart failure through natural products' modulation of the ferroptosis pathway.

METHODS

By comprehensively searching authoritative databases like PubMed, Web of Science, and China National Knowledge Infrastructure with keywords such as "heart failure", "cardiovascular disease", "heart disease", "ferroptosis", "natural products", "active compounds", "traditional Chinese medicine formulas", "traditional Chinese medicine", and "acupuncture", we aim to systematically review the mechanism of ferroptosis and its link with heart failure. We also want to explore natural small-molecule compounds, traditional Chinese medicine formulas, and acupuncture therapies that can inhibit ferroptosis to improve heart failure.

RESULTS

In this review, we not only trace the evolution of the concept of ferroptosis and clearly distinguish it from other forms of cell death but also establish a comprehensive theoretical framework encompassing core mechanisms such as iron overload and system xc-/GSH/GPX4 imbalance, along with multiple auxiliary pathways. On this basis, we innovatively link ferroptosis with various types of heart failure, covering classic heart failure types and extending our research to pre-heart failure conditions such as arrhythmia and aortic aneurysm, providing new insights for early intervention in heart failure. Importantly, this article systematically integrates multiple strategies of natural products for interfering with ferroptosis, ranging from monomeric compounds and bioactive components to crude extracts and further to traditional Chinese medicine formulae. In addition, non-pharmacological means such as acupuncture are also included.

CONCLUSION

This study fills the gap in the systematic description of the relationship between ferroptosis and heart failure and the therapeutic strategies of natural products, aiming to provide patients with more diverse treatment options and promote the development of the heart failure treatment field.

A novel way of regression of pregnant corpus luteum during parturition in mice: The ferroptosis associated with NCOA4-mediated ferritinophagy

Numerous studies have shown that inappropriate regression of corpus luteum would lead to adverse pregnancy outcomes during gestation. However, the detailed mechanisms and types of programmed cell death involved in the regression of pregnant corpus luteum are largely unknown. Here, we investigated whether ferroptosis and ferritinophagy were involved in luteal regression during parturition in mice and related mechanisms. The results showed that ferroptosis and ferritinophagy were both involved in luteal regression during mice peri-parturition in vivo. Erastin (ferroptosis agonist) treatment significantly accelerated luteal regression and induced premature labor in pregnant mice. PGF2α treatment induced the ferroptosis and ferritinophagy of luteal cells in vitro. Nevertheless, inhibition or promotion of ferroptosis significantly altered the states of PGF2α-induced luteal cell viability and ferroptosis. Furthermore, inhibition of autophagy (3-methyladenine co-treatment) alleviated PGF2α-induced ferritinophagy and ferroptosis of luteal cells, and knockdown of NCOA4 reduced the degradation of FTH1 and the level of ferroptosis of luteal cells induced by PGF2α. In summary, our current data demonstrated that the ferroptosis associated with NCOA4-mediated ferritinophagy was a novel way of luteal regression during peri-parturition in mice. Targeting ferroptosis in the corpus luteum may be a therapeutic strategy for preventing luteal insufficiency in the future.

Honokiol ameliorates pyroptosis in intestinal ischemia‑reperfusion injury by regulating the SIRT3‑mediated NLRP3 inflammasome

Intestinal ischemia‑reperfusion (IIR) injury is caused by the restoration of blood supply after a period of ischemia. It occurs in numerous clinical pathologies, such as intestinal obstruction, incarcerated hernia and septic shock, with mortality rates of 50‑80%. Honokiol (HKL), isolated from the herb Magnolia officinalis, is a biphenolic natural product with antioxidative, antibacterial, antitumor and anti‑inflammatory properties. Additionally, HKL has protective effects in ischemia‑reperfusion injuries, but its role and specific mechanisms in IIR injury are yet to be elucidated. In the present study, the superior mesenteric artery was ligated in rats to establish an IIR model. Hematoxylin and eosin staining and ELISA revealed that HKL administration ameliorated IIR‑induced injury in rats, which was demonstrated by a reduced destruction to the intestinal mucosa, as well as a reduced serum intestinal fatty acid‑binding protein concentration and Chiu's score in 10 mg/kg HKL treated IIR‑induced rats compared with those without HKL treatment. Additionally, immunohistochemical (IHC) staining and western blotting revealed that the occludin and tight junction protein 1 protein levels were increased in the 10 mg/kg HKL treated IIR‑induced rats compared with those without HKL treatment. Furthermore, an in vitro hypoxia/reoxygenation (H/R) cell model was established using IEC‑6 cells. Cell Counting Kit‑8 and lactate dehydrogenase (LDH) assays indicated that HKL mitigated the H/R‑inhibited cell viability and decreased the LDH levels in cell supernatants. Mechanistically, immunofluorescent (IF) staining and western blotting revealed that HKL inhibited H/R‑triggered pyroptosis. Furthermore, Mito‑Tracker, mitochondrial membrane potential and MitoSOX staining as well as western blotting revealed that reducing mitochondrial reactive oxygen species (ROS) inhibited the H/R‑induced pyroptosis by mitigating mitochondrial dysfunction. In the present H/R cell model, HKL improved the mitochondrial function by increasing the expression of sirtuin 3 (SIRT3), while IF staining and western blotting indicated that silencing SIRT3 notably reduced the beneficial effect of HKL on pyroptosis. In addition, IHC staining and western blotting revealed that HKL treatment mitigated the IIR‑induced pyroptosis in rats. Therefore, HKL treatment may mitigate IIR‑induced mitochondrial dysfunction and reduce mitochondrial ROS production by increasing the expression of SIRT3 protein, potentially resulting in an inhibition of pyroptosis during IIR.

Therapeutic Approaches Targeting Ferroptosis in Cardiomyopathy

The term cardiomyopathy refers to a group of heart diseases that cause severe heart failure over time. Cardiomyopathies have been proven to be associated with ferroptosis, a non-apoptotic form of cell death. It has been shown that some small molecule drugs and active ingredients of herbal medicine can regulate ferroptosis, thereby alleviating the development of cardiomyopathy. This article reviews recent discoveries about ferroptosis, its role in the pathogenesis of cardiomyopathy, and the therapeutic options for treating ferroptosis-associated cardiomyopathy. The article aims to provide insights into the basic mechanisms of ferroptosis and its treatment to prevent cardiomyopathy and related diseases.

Nrf2-Mediated Ferroptosis Is Involved in Berberine-Induced Alleviation of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the most common and serious complication of diabetes mellitus. Currently, there is a lack of safe and effective preventive strategies for DKD. The study aimed to explore the preventive effects and potential mechanisms of berberine (BBR) against DKD. In the in vivo experiments, we established a DKD rat model induced by the combination of high-fat diet and streptozotocin to investigate the preventive effect of BBR on DKD. Subsequently, in vitro experiments using human renal tubular epithelial cells (HK-2 cells) were performed to further validate the effect of BBR on renal tubular epithelial cell ferroptosis induced by advanced glycation end products (AGEs). In vivo, we found that BBR improved renal function and attenuated inflammatory cell infiltration, podocyte injury, and iron deposition in renal tissue in DKD rats. In addition, in vitro experiments showed that BBR attenuated HK-2 cell ferroptosis induced by AGEs. We further identified Nrf2 as a direct binding target of BBR by molecular docking and Surface Plasmon Resonance (SPR). Then, immunohistochemistry and Western Blot results demonstrated that BBR could activate the Nrf2 pathway, initiate the endogenous antioxidant system, and inhibit the occurrence of AGEs-induced ferroptosis. Moreover, silencing of Nrf2 by siRNA technology eliminated the protective effect of BBR on AGEs-induced ferroptosis. Collectively, our results supported that BBR could inhibit oxidative stress and ferroptosis by targeting activation of the Nrf2 pathway, thereby delaying the disease progression of DKD, providing a new scientific basis and perspective for the prevention and treatment of DKD.

Berberine treatment inhibits ferroptosis in NIT-1 murine pancreatic cell line via inhibiting OGT expression levels

Recently, the prevalence of diabetes mellitus (DM) in the world continues to rise, which has seriously threatened human health. Enhanced pancreatic β-cell death is one of the important factors in the pathogenesis of type 1 diabetes mellitus (T1DM). Berberine, an alkaloid, plays a series of pharmacological functions in many disease. The purpose of this study was to explore the specific mechanisms of berberine in the high glucose (HG) stimulated pancreatic β-cell. The 30 mM D-glucose stimulated mouse pancreatic β cells (NIT-1) was used to estabilish T1DM model in vitro. Then the cell viability was detected by CCK-8 assay. The lactic dehydrogenase (LDH), reactive oxygen species (ROS), Iron, malondialdehyde (MDA), glutathione (GSH), and glutathione peroxidase 4 (GPX4) levels were determined by corresponding kits. The cell death was evaluated by PI staining. Western blot was performed to measure the O-linked N-acetylglucosamine (O-GlcNAc) and O-GlcNAc transferase (OGT) protein levels. The results showed that berberine treatment significantly increased the cell viability, GPX4 activity and GSH levels, and decreased the ROS, Iron, MDA levels and PI positive cells in the HG stimulated NIT-1 cells. Additionally, the molecular docking analysis showed that berberine could bind to OGT. Berberine treatment significantly decreased the global O-GlcNAc levels and OGT protein expression in the HG stimulated NIT-1 cells. Furthermore, OGT overexpression reversed the role of berberine in the HG stimulated NIT-1 cells. This study demonstrated that berberine treatment inhibited the ferroptosis of pancreatic β-cell under high-glucose condition via decreasing the OGT expressions.

Targeting Acyl-CoA synthetase long-chain family member 4: a potential approach for the treatment of cerebral ischemia/reperfusion injury

Cerebral ischemia/reperfusion injury causes high rates of morbidity and death. Recent studies have shown that ferroptosis, a type of controlled cell death brought on by lipid peroxidation, worsens cerebral ischemia/reperfusion injury. Acyl-CoA synthetase long-chain family member 4 (ACSL4) has emerged as a crucial enzyme in lipid metabolism and ferroptosis in the context of ischemia/reperfusion injury, influencing neuronal cell death. Increased vulnerability to ferroptosis and worsening ischemia/reperfusion injury outcomes are linked to elevated ACSL4 levels. Comprehending the molecular processes underlying ACSL4-mediated ferroptosis may result in novel approaches to treating cerebral ischemia/reperfusion injury. The present review discusses ACSL4 as a potential target for treating cerebral ischemia/reperfusion injury, focusing on ACSL4-mediated ferroptosis and signal transduction.

Targeting mitochondria quality control for myocardial ischemia-reperfusion injury

Cardiovascular disease (CVD) remains the leading global cause of mortality. Acute myocardial infarction (AMI) refers to acute myocardial ischemia resulting from thrombosis secondary to coronary atherosclerosis, which poses a major threat to human health. Clinically, timely revascularization (reperfusion) represents the basis of clinical treatment for AMI. However, secondary myocardial ischemia-reperfusion injury (MIRI) caused by reperfusion often exacerbates damage, representing a major challenge in clinical practice. Mitochondria represent essential organelles for maintaining cardiac function and cellular bioenergetics in MIRI. In recent years, the role of mitochondrial quality control (MQC) in maintaining cell homeostasis and mediating MIRI has been extensively studied. This review provides a concise overview of MQC mechanisms at the molecular, organelle, and cellular levels and their possible complex regulatory network in MIRI. In addition, potential treatment strategies targeting MQC to mitigate MIRI are summarized, highlighting the gap between current preclinical research and clinical transformation. Overall, this review provides theoretical guidance for further research and clinical translational studies.

Outer membrane vesicles of Porphyromonas gingivalis impede bone regeneration by inducing ferroptosis via the Hippo-YAP signaling pathway

BACKGROUND

Although increasing evidence confirms that oral microbiota imbalance is a critical factor inhibiting bone regeneration, the specific mechanisms have remained unexplored. This study aims to use periodontitis as a model of oral microbiota imbalance to investigate the specific mechanisms that inhibit bone regeneration in extraction sockets.

METHODS

Cone Beam Computed Tomography (CBCT) data of extraction sockets were collected from patients with and without periodontitis to confirm the influence of the periodontitis microenvironment on bone regeneration in extraction sockets. Furthermore, GW4869-pretreated Porphyromonas gingivalis (Pg) and normal Pg were used to build a periodontitis model, and then the bone regeneration in extraction sockets under these conditions was detected by H&E staining, Masson's staining and micro-CT analysis. In vitro, the effect of Pg-derived OMVs on osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) was examined. RNA sequencing, FerroOrange, malondialdehyde assay, transmission electron microscopy, qRT‒PCR, and western blotting analysis were performed.

RESULTS

CBCT analysis showed that periodontitis significantly inhibited new bone formation in the extraction sockets in patients. Micro-CT and Histological analysis revealed that inhibiting OMVs released from Pg alleviated the inhibition of bone regeneration in extraction sockets under Pg imbalance. Moreover, Pg-derived OMVs treatment deteriorated bone regeneration in extraction sockets. In vitro, results showed that Pg-derived OMVs inhibited osteogenic differentiation of BMSCs. Furthermore, the results indicated a significant upregulation of ferroptosis in OMVs-treated BMSCs. Notably, targeting ferroptosis promoted osteogenic differentiation of BMSCs and bone regeneration in extraction sockets, as compared with the OMVs-treated group. Mechanistic studies have shown that Pg-derived OMVs promoted BMSCs ferroptosis via the Hippo- Yes-associated protein (YAP) pathway.

CONCLUSION

This study shows that a Pg microbiota imbalance inhibits bone regeneration by secreting OMVs from Pg to induce ferroptosis in BMSCs. Mechanically, we illustrated that OMVs induce ferroptosis through the Hippo-YAP pathway. These findings might provide a new insight and potential therapeutic target to promote bone regeneration under oral microbiota imbalance.

ALDH7A1 protects against ferroptosis by generating membrane NADH and regulating FSP1

Ferroptosis is a form of cell death due to iron-induced lipid peroxidation. Ferroptosis suppressor protein 1 (FSP1) protects against this death by generating antioxidants, which requires nicotinamide adenine dinucleotide, reduced form (NADH) as a cofactor. We initially uncover that NADH exists at significant levels on cellular membranes and then find that this form of NADH is generated by aldehyde dehydrogenase 7A1 (ALDH7A1) to support FSP1 activity. ALDH7A1 activity also acts directly to decrease lipid peroxidation by consuming reactive aldehydes. Furthermore, ALDH7A1 promotes the membrane recruitment of FSP1, which is instigated by ferroptotic stress activating AMP-activated protein kinase (AMPK) to promote the membrane localization of ALDH7A1 that stabilizes FSP1 on membranes. These findings advance a fundamental understanding of NADH by revealing a previously unappreciated pool on cellular membranes, with the elucidation of its function providing a major understanding of how FSP1 acts and how an aldehyde dehydrogenase protects against ferroptosis.

Gut microbiota-derived glutathione from metformin treatment alleviates intestinal ferroptosis induced by ischemia/reperfusion

BACKGROUND

Intestinal ischemia/reperfusion injury (IIRI) is a life-threatening condition caused by multiple organ and system failures induced by dysbiosis and gut leakage. Metformin has demonstrated efficacy in protecting against IIRI, although the precise role of the gut microbiota in the underlying mechanism is still ambiguous.

METHODS

This study examined intestinal barrier function and ferroptosis-related parameters in mice with IIRI following treatment with metformin. Additionally, dirty cages and antibiotics were utilized to investigate the impact of the microbiota on the effects of metformin. The analysis included an assessment of the microbial composition of metformin-treated mice and the biosynthetic activity of specific metabolites.

RESULTS

Metformin effectively reduced gut leakage induced by IIRI, as evidenced by decreased intestinal permeability and increased Occludin, ZO-1, Claudin-1, and MUC-1 expression. A decrease in the expression of the pro-ferroptotic proteins ACSL4, TFR1, and VDAC2/3 and a decrease in dihydroethidium (DHE) fluorescence, iron, malondialdehyde (MDA), and myeloperoxidase (MPO) were further observed in metformin-treated mice. In contrast, the damage to the GPX4/GSH system caused by IIRI was reversed after metformin treatment, as shown by increases in GPX4, SLC7A11, and GSH. The antiferroptotic effects of metformin were phenocopied by its fecal microbiota but were eliminated by antibiotic intake. 16S rRNA analysis revealed that the metformin-modulated gut microbiota was characterized by increased Lactobacillus murinus, which expressed higher levels of GshF that contributed to the mitigation of IIRI.

CONCLUSIONS

Murine gut microbiota mediated the anti-ferroptotic effect of metformin on IIRI, and the resulting increase in microbial GSH synthesis could serve as a critical pathway for anti-IIRI.

Human antigen R -mediated autophagy-related gene 3 methylation enhances autophagy-driven ferroptosis in Crohn's disease colitis

BACKGROUND AND AIMS

Crohn's disease (CD) is a chronic inflammatory disorder that can affect any part of the gastrointestinal tract, with the exact etiology remaining unclear. Recent studies have implicated the role of human antigen R (HuR) in the pathogenesis of various inflammatory diseases, including CD. However, the role of HuR in the modulation of CD remains underexplored. Therefore, this study aimed to investigate the mechanistic involvement of HuR in CD.

METHODS

We established colitis models using human intestinal epithelial cells and lipopolysaccharide and dextran sulfate sodium-induced mice. Additionally, by knocking out HuR in both cell and animal models, we validated the role of HuR in autophagy and ferroptosis. The role of HuR in regulating ferroptosis accompanied by autophagy activation in CD was detected using ELISA, flow cytometry, immunofluorescence, transmission electron microscopy, Western blot, and RT-qPCR. The demethylation level of ATG3 and the stability of ATG3 mRNA regulated by HuR were detected using immunofluorescence, RIP, and MeRIP-qPCR. The effect of HuR on DSS-induced colitis was evaluated using DAI score, H&E staining, TUNEL staining, and immunohistochemistry.

RESULTS

The results show that HuR expression is significantly increased in CD colonic inflammation. Compared with the control group, the model group mice exhibited decreased levels of lipid peroxidation markers glutathione and superoxide dismutase, elevated malondialdehyde and reactive oxygen species levels, and reduced expression of iron-related proteins glutathione peroxidase 4, ferritin heavy chain protein 1, and solute carrier family 7 member 11. Additionally, the expression of autophagy-related proteins microtubule-associated protein 1 A/1B-light chain 3, beclin-1, and autophagy related 3 (ATG3) was upregulated, while p62 expression was downregulated. In both in vitro and in vivo models, HuR knockout reversed these changes induced by lipopolysaccharide and dextran sulfate sodium, concomitant with improved tissue pathology. Mechanistically, HuR enhances autophagy-mediated ferroptosis in CD colonic inflammation by regulating ATG3 methylation and mRNA stability.

CONCLUSION

HuR accelerates colonic inflammation in CD by regulating ATG3 methylation, which enhances autophagy-mediated ferroptosis. Knockout of HuR alleviates Crohn's colitis. This finding provides a potential therapeutic target for the treatment of CD.

Extracellular vesicles derived from bone marrow mesenchymal stem cells regulate SREBF2/HMGB1 axis by transporting miR-378a-3p to inhibit ferroptosis in intestinal ischemia-reperfusion injury

Intestinal ischemia-reperfusion (II/R) injury represents a life-threatening and complex pathophysiological process that remains challenging to treat clinically, and emerging evidence suggests that ferroptosis plays an essential role in its pathogenesis. This study aimed to investigate whether extracellular vesicles derived from bone marrow mesenchymal stem cells (BMSC-EVs) can mitigate II/R-induced ferroptosis in a murine model. Using a bioinformatics database, we initially identified genes with abnormal expression patterns in II/R injury. Then, we confirmed the association between II/R injury, ferroptosis, and the HMGB1/SREBF2 axis through in vivo and in vitro experiments. To determine the role of HMGB1 in hypoxia/reoxygenation (H/R)-induced ferroptosis in Caco-2 cells, we transfected cells with either sh-HMGB1 or control sh-NC constructs and developed an H/R model in vitro. Subsequently, we examined factors regulating HMGB1-mediated ferroptosis in Caco-2 cells and assessed the effect of BMSC-EVs on this process. To further explore the mechanism underlying the protective effects of BMSC-EVs in II/R injury, we screened for miRNAs with reduced expression during II/R and verified their involvement. Among these, miR-378a-3p was identified as a candidate for regulating ferroptosis. To confirm its functional role, we treated II/R mice with BMSC-EVs overexpressing miR-378a-3p and assessed the outcomes. Our findings revealed that HMGB1, which is a key regulatory factor of ferroptosis, was significantly upregulated during II/R injury, and its knockdown alleviated H/R-induced ferroptosis in Caco-2 cells. We also found that SREBF2 directly regulates HMGB1 expression to promote H/R-induced ferroptosis in vitro. Importantly, BMSC-EVs alleviated II/R injury by suppressing ferroptosis in Caco-2 cells, and mechanistically, miR-378a-3p, a miRNA derived from BMSC-EVs, inhibited II/R-induced ferroptosis by modulating the SREBF2/HMGB1 axis. In conclusion, BMSC-EVs may exert protective effects against II/R injury by delivering miR-378a-3p, which regulates the SREBF2/HMGB1 axis to suppress ferroptosis, providing important insights into the pathological mechanisms underlying II/R injury and potential therapeutic strategies for its management.

Iron overload enhances the susceptibility to cysteine deprivation-induced ferroptosis in non-small cell lung cancer cells

Ferroptosis is an iron-dependent regulated cell death characterized by lipid peroxidation accumulation. Due to the high iron demand of cancer cells, targeting ferroptosis is considered a promising approach for cancer therapy. This study aimed to elucidate the mechanisms underlying the differences in ferroptosis sensitivity in non-small cell lung cancer (NSCLC) cells and identify strategies to overcome ferroptosis resistance. H1299 cells were more sensitive to cysteine deprivation-induced ferroptosis and exhibited higher transferrin receptor (TfR) expression than H460 cells. Transferrin enhanced ferroptosis in cysteine-deprived H1299 cells, while TfR knockdown reduced ferroptosis, suggesting the involvement of TfR/transferrin system in this process. In H460 cells with low TfR expression, transferrin treatment did not induce ferroptosis under cysteine deprivation, indicating that the TfR/transferrin system was not involved. However, treatment with cell-permeable ferric ammonium citrate increased the sensitivity of ferroptosis to cysteine deprivation or RSL3 treatment. In conclusion, iron overload could be a potential strategy to overcome ferroptosis resistance in NSCLC.

Ferroptosis Inhibition: A Key Opportunity for the Treatment of Ischemia/Reperfusion Injury in Liver Transplantation

The outcome after liver transplantation has improved in recent years, which can be attributed to superior storage and transportation conditions of the organs, as well as better peri- and postoperative management and advancements in surgical techniques. Nevertheless, there is an increasing discrepancy between the need for organs and their availability. Consequently, the mortality rate on the waiting list is high and continues to rise. One way of counteracting this trend is to increase the use of "expanded criteria donors." This means that more and more donors will be included, especially those who are older and having additional comorbidities (eg, steatosis). A major complication of any transplantation is the occurrence of ischemia/reperfusion injury (IRI), which often leads to liver dysfunction and failure. However, there have been various promising approaches to minimize IRI in recent years, but an effective and clinically applicable method to achieve a better outcome for patients after liver transplantation is still missing. Thereby, the so-called marginal organs are predominantly affected by IRI; thus, it is crucial to develop suitable and effective treatment options for patients. Recently, regulated cell death mechanisms, particularly ferroptosis, have been implicated to play a major role in IRI, including the liver. Therefore, inhibiting this kind of cell death modality presents a promising therapeutic approach for the management of this yet untreatable condition. Thus, this review provides an overview of the role of ferroptosis in liver IRI and transplantation and discusses possible therapeutic solutions based on ferroptosis inhibition to restrain IRI in marginal organs (especially steatosis and donation after circulatory death organs).

AMPK mediates the anti-ferroptosis effect of acupuncture in cerebral ischemia-reperfusion rats

BACKGROUND

Acupuncture is clinically effective in the treatment of ischemic stroke. The report suggests that energy stress inhibits ferroptosis in part through AMPK. However, whether the effect of activating AMPK is related to ferroptosis in ischemic stroke and whether acupuncture can achieve neuroprotection against ischemic brain injury through the pathway of inhibiting ferroptosis by activating AMPK has not been confirmed.

METHODS

In this experiment, all rats were randomly divided into 4 groups: Sham group, MCAO/R group, MA (MCAO/R + acupuncture) group, and MAM (MCAO/R + acupuncture + metformin) group. The middle cerebral artery occlusion/reperfusion injury (MCAO/R) model was created by the wire embolism method, and the MA and MAM groups received acupuncture treatment with electrotherapy (1 mA, 2/15 Hz, 20 min each), while the MAM group continued to receive metformin (oral gavage 200 mg/kg) after successful modelling. Neurological deficit score and infarct volume were measured, Prussian blue staining and mitochondrial structural changes were observed, and Fe2+ and MDA levels were determined in the brain tissue of the rats. Western blot results were analyzed to determine differences in the expression of TFR1, SLC7A11, GPX4 and AMPK、p-AMPK proteins in order to explore the possible pathological processes involved in cerebral ischemia at behavioral, histological and molecular levels and the possible protective mechanisms of acupuncture.

RESULTS

Acupuncture attenuated ischemia-reperfusion-induced brain damage and mitochondrial damage. Further studies showed that acupuncture reduced the levels of Fe2+, MDA and the expression of TFR1 protein and increased the expression of SLC7A11 and GPX4 protein in the diseased hippocampal region of MCAO/R rats. In addition, metformin, as an AMPK activator, significantly enhanced the protective effect of acupuncture on cerebral ischemic injury and enhanced the acupuncture-mediated reduction of Fe2+, MDA levels and TFR1 protein expression and the increase of SLC7A11 and GPX4 protein expression in the lesioned hippocampal region of MCAO/R rats.

CONCLUSIONS

These findings suggest that acupuncture can inhibit ferroptosis and thus exert a protective effect against ischemic brain injury, and that this mechanism may be achieved by activating AMPK. This extends the mechanism of action of acupuncture in the treatment of ischemic stroke.

Modulation of Macrophage ferroptosis under the guide of infrared thermography promotes the healing of pressure injuries

BACKGROUND

Accurately recognizing and regulating the transition time of macrophages to a pro- (M1-like) or anti-inflammatory (M2-like) state is essential for improving chronic inflammation in pressure injuries (PIs).

OBJECTIVE

This study aimed to evaluate the effectiveness of infrared thermography (IRT) in measuring wound temperature of PIs for the purpose of guiding treatment in regulating chronic inflammation.

METHODS

The healing process of 21 patients with PIs was monitored using IRT prospectively followed for 30 days. The wound temperature changing pattern of different healing outcomes were analyzed and calculated the optimal wound temperature range to guide the treatment time of anti-inflammation for 100 patients with PIs accurately. Additionally, the molecular mechanisms underlying the observed temperature changes in a mouse model of PI were investigated, and the effect of IRT-guided chronic inflammation targeting ferroptosis modulation on PIs was validated.

RESULTS

The application of IRT to monitor PIs temperatures outside the 36.23 °C to 37.37 °C range is indicative of a potential risk indicator, which allows for the timely guidance of treatment to markedly enhance the efficacy of PIs healing outcomes. This wound temperature change was also observed during the process of PIs healing in mice, as a result of the imbalance of M1-like/M2-like macrophages and the subsequent chronic inflammation. Mechanically, evidence indicates that ferroptosis is hyperactivated in PIs, and the enrichment of M1-like macrophages with iNOS/NO• can enhance their resistance to ferroptosis compared with M2-like macrophages, resulting in the imbalance of M1-like/M2-like macrophages and subsequent alteration of wound temperature.

CONCLUSIONS

The modulation of M2-like macrophage resistance to ferroptosis in PIs by NO• donors, suggesting by IRT-monitored temperature changes, has been demonstrated to significantly improve chronic inflammation. This establishes a foundation for the application of IRT to direct a therapeutic strategy for the precise promotion of PIs healing.

The Efficacy of Ferroptosis Inhibition on Ischemia-Reperfusion Injury of Abdominal Organs: A Systematic Review and Meta-analysis

Solid organ transplantation is hampered by complications that arise after ischemia-reperfusion injury (IRI), a detrimental type of injury for which no adequate treatment options are available. Ferroptosis, an iron-dependent form of regulated cell death, is a major driver of IRI. This systematic review and meta-analysis summarizes the effects of pharmacological ferroptosis inhibition in abdominal organs in the setting of IRI. PubMed, Embase, Web of Science and Cochrane were searched for concepts "ferroptosis" and "IRI" in August 2023. To allow for meta-analyses, inhibitors were divided into different intervention pathways: (I) lipophilic radical scavengers, (II) iron chelators, (III) antioxidants, (IV) lipid metabolism inhibitors, (V) combination treatments, and (VI) others. When available, organ function and injury effect sizes were extracted and used for random-effects meta-analyses. In total 79 articles were included, describing 59 unique inhibitors in kidney, liver, and intestinal IRI. No studies in pancreas were found. Overall bias and study quality was unclear and average to low, respectively. Apart from 1 clinical study, all inhibitors were tested in preclinical settings. The vast majority of the studies showed ferroptosis inhibition to be protective against IRI under various treatment conditions. In liver and kidney IRI, meta-analyses on standardized effect sizes from 43 articles showed a combined protective effect against IRI compared with a nontreated controls for all analyzed intervention pathways. In conclusion, ferroptosis inhibition protects against abdominal IRI in preclinical research. Important questions regarding optimal intervention pathway, bioavailability, optimal dosage, side effects etc. should be addressed before clinical introduction.

Hydroxysafflor yellow A inhibits neuronal ferroptosis and ferritinophagy in ischemic stroke

Ischemic stroke is a significant cause of disability and mortality on a global scale, with neuronal dysfunction playing a critical role in its pathogenesis. Conventional treatment approaches for ischemic stroke involve surgical interventions and thrombolytic therapy, yet these methods frequently result in ischemia/reperfusion (I/R) injury. Recent studies have underscored the implication of diverse programmed cell death mechanisms, including ferroptosis, in the progression of ischemic stroke. Ferroptosis, a newly recognized form of cell death reliant on iron, is intricately linked to various neurological conditions. Despite the existing body of research on ferritinophagy and neuronal ferroptosis in the context of cerebral ischemia-reperfusion injury, there is a lack of understanding regarding the mechanisms involved in neuronal ferroptosis. This study seeks to explore the relationship between neuronal autophagy and neuronal ferroptosis using in vivo and in vitro models of cerebral ischemia/reperfusion. The findings of our study reveal a significant upregulation of the ferritinophagy-associated protein NCOA4 following cerebral ischemia/reperfusion, concomitant with the initiation of ferroptosis in neuronal cells. This observation offers compelling support for a direct association between neuronal ferritinophagy and ferroptosis. Hydroxysafflor Yellow A (HSYA), a traditional Chinese herb, shows promise in reducing brain ischemia/reperfusion injury, but its exact protective mechanism is still unknown. Our study reveals a new way HSYA protects the brain by preventing neuronal ferroptosis after a stroke, a mechanism not previously reported.

Regulation of SLC7A11 by LncRNA GPRC5D-AS1 mediates ferroptosis in skeletal muscle: Mechanistic exploration of sarcopenia

Sarcopenia is a chronic, progressive disease characterized by the gradual loss of skeletal muscle strength and mass. This study investigates the role of the long non-coding RNA GPRC5D-AS1 in the development and progression of sarcopenia through its regulation of SLC7A11. Skeletal muscle samples were obtained from sarcopenia patients and healthy controls to assess the expression levels of GPRC5D-AS1 and SLC7A11. Flow cytometry was used to evaluate iron content, lipid peroxidation, and antioxidant markers. A ferroptosis model was established in human skeletal muscle cells (HSKM) using the inducer erastin, and GPRC5D-AS1 overexpression plasmids were introduced to observe their effects on cell proliferation and ferroptosis indicators. In the sarcopenia group, both GPRC5D-AS1 and SLC7A11 expression levels decreased significantly, along with SLC7A11 protein translation. Erastin treatment markedly reduced cell viability and increased iron content, elevating ferroptosis marker genes (COX2, ACSL4, PTGS2, NOX1) while reducing GPX4 and FTH1 levels. The overexpression of GPRC5D-AS1 reversed these changes, enhancing antioxidant capacity and cell survival. Conversely, silencing SLC7A11 diminished the protective effects of GPRC5D-AS1 on cell proliferation and ferroptosis. These findings suggest that GPRC5D-AS1 overexpression increases SLC7A11 expression and reduces ferroptosis incidence in HSKM.

Identification of novel hub gene and biological pathways associated with ferroptosis in In-Stent restenosis

BACKGROUND

In-stent restenosis (ISR) is one of the most significant complications following percutaneous coronary intervention (PCI) in patients with coronary artery disease (CAD). Ferroptosis is a novel cell death mode characterized by iron overload and lipid peroxidation. However, the role of ferroptosis in vascular smooth muscle cells (VSMCs) regulating neointimal formation during restenosis remains unclear.

OBJECTIVE

The current study aims to reveal the molecular targets for neointimal hyperplasia through integrated analysis of data from gene expression omnibus (GEO) databases and single-cell sequencing (scRNA-Seq).

METHODS AND RESULTS

In this study, we screened ten common differentially expressed genes (Co-DEGs) including BID, SP1, NCF2, HERPUD1, RICTOR, LAMP2, CAT, ACSL1, CS, and ANO6 from the GEO and FerrDb V2. GO/KEGG analyses indicated that metabolic reactions, particularly glyoxylate and dicarboxylate metabolism pathways, are the main molecular events. Immune infiltration analysis showed significant correlations between the expression of Co-DEGs and the infiltration of macrophages, dendritic cells, eosinophils, and neutrophils. Moreover, we identified SP1 as a potential therapeutic target associated with ferroptosis in ISR and constructed a lncRNA-miRNA-SP1 regulatory network. Using scRNA-Seq data to validate the expression of Co-DEGs in the neointima, we found that metabolic pathways such as carbon metabolism, peroxisomes, and reactive oxygen species were enriched. Immune infiltration examined the relationship between Co-DEGs and immune cells, revealing negative correlation between SP1 and neutrophils, and positive correlation between BID and macrophages.

CONCLUSION

The integrated analyses identified SP1 as a key regulator of ferroptosis in ISR and proposed its potential to be a novel therapeutic target of ISR. The construction of ceRNA network based on SP1 might contribute to new treatment strategy and drug development for ISR.

Evaluation of proanthocyanidins in treating Type 2 diabetic osteoporosis via SIRT6/Nrf2/GPX4 pathways

This study investigates the therapeutic potential of proanthocyanidins (PAC) in addressing Type 2 diabetic osteoporosis (T2DOP) by activating the SIRT6/Nrf2/GPX4 signaling pathways. T2DOP is characterized by compromised bone structure and heightened oxidative stress, where ferroptosis plays a pivotal role. Utilizing a T2DOP mouse model and MC3T3-E1 cells under high glucose conditions, we evaluated the impact of PAC on bone health and iron homeostasis. Our results, obtained through micro-CT, histological staining, Western blot, and immunofluorescence analyses, revealed reductions in bone density and decreased GPX4 expression in T2DOP conditions, indicating ferroptosis and oxidative stress. However, PAC treatment improved trabecular bone structure, reduced bone marrow adipocytes, decreased oxidative stress, and enhanced expression of key osteogenic proteins. These findings highlight PAC's potential in mitigating T2DOP through the SIRT6/Nrf2/GPX4 pathways, offering promising therapeutic insights for managing diabetic osteoporosis.

Study of the relationship between iron metabolism disorders and sepsis-associated liver injury: A prospective observational study

BACKGROUND

Sepsis-associated liver injury (SALI) refers to secondary liver function impairment caused by sepsis, patients with SALI often have worse clinical outcomes. The early identification and assessment of the occurrence and progression of SALI are pressing issues that urgently need to be resolved.

AIM

To investigate the relationship between iron metabolism and SALI.

METHODS

In this prospective study, 139 patients were recruited, with 53 assigned to the SALI group. The relationships between SALI and various iron metabolism-related biomarkers were examined. These biomarkers included serum iron (SI), total iron-binding capacity (TIBC), serum ferritin, transferrin, and transferrin saturation. To identify independent risk factors for SALI, both univariate and multivariate logistic regression analyses were performed. Additionally, receiver operating characteristic curve analysis was utilized to assess the predictive value of these biomarkers for the occurrence of SALI.

RESULTS

There were no statistically significant differences in age, sex, body mass index, Sequential Organ Failure Assessment scores (excluding liver function), or APACHE II scores between the two groups of patients. Compared with the sepsis group, the SALI group presented significantly higher SI (P < 0.001), TIBC (P < 0.001), serum ferritin (P = 0.001), transferrin (P = 0.005), and transferrin saturation levels (P < 0.001). Multivariate logistic regression analysis revealed that SI (odds ratio = 1.24, 95% confidence interval: 1.11-1.40, P < 0.001) and TIBC levels (odds ratio = 1.13, 95% confidence interval: 1.05-1.21, P < 0.001) were independent predictors of SALI. Receiver operating characteristic curve analysis revealed that SI and TIBC had areas under the curve of 0.816 and 0.757, respectively, indicating moderate predictive accuracy for SALI.

CONCLUSION

Iron metabolism disorders are closely associated with the development of SALI, and SI and TIBC may serve as potential predictive biomarkers. The combined use of SI and TIBC has superior diagnostic efficacy for SALI. These findings provide valuable insights for the early identification and management of SALI among patients with sepsis.

Inhibition of ACSL4 Attenuates Behavioral Deficits by Regulating Ferroptosis in a Murine Model of Systemic Lupus Erythematosus

Neuropsychiatric systemic lupus erythematosus (NPSLE) is a disorder with a poor prognosis characterized by psychiatric and neurological manifestations directly associated with systemic lupus erythematosus (SLE). Neutrophil ferroptosis has been identified as a significant contributor to neutropenia and disease progression in SLE, but its role in NPSLE remains unclear. Female MRL/lpr and MRL/Mpj mice were used. The selective ferroptosis inhibitor liproxstatin-1 and the acyl-CoA synthetase long-chain family member 4 (ACSL4) inhibitor rosiglitazone were administered separately. Assessments included behavioral testing, transmission electron microscopy (TEM), ELISA, Western blotting, RT-PCR, and Nissl staining. Our data showed that neurons in the brain parenchyma undergo ferroptosis, with decreased glutathione peroxidase 4 (GPX4) expression and increased levels of lipid peroxidation indicators and have the typical morphology of ferroptosis confirmed by transmission electron microscopy. Selective ferroptosis inhibitor liproxstatin-1 attenuated the neuropsychiatric manifestations, including depression-like and impulsive behaviors, of MRL/lpr mice. ACSL4 is the main enzyme in lipid metabolism. Our study further found that the utilization of rosiglitazone by inhibiting ACSL4 could also significantly attenuate neuropsychiatric manifestations of MRL/lpr mice. Moreover, blocking ACSL4 might considerably boost GPX4 levels and decrease lipid peroxidation indicators in NPSLE, with reduced neuronal damage, as well as reduced neuroinflammation. This study concluded that inhibiting ACSL4 could facilitate the recuperation of behavioral deficits by suppression of ferroptosis in NPSLE, implying that ACSL4 might be a potential new therapeutic focus for NPSLE.

Danggui Shaoyao San ameliorates Alzheimer's disease by regulating lipid metabolism and inhibiting neuronal ferroptosis through the AMPK/Sp1/ACSL4 signaling pathway

Introduction

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by cognitive decline; recent studies suggest that neuronal ferroptosis plays a key role in its pathogenesis. Danggui Shaoyao San (DSS), a traditional Chinese medicine formula, has shown demonstrated neuroprotective effects, but its precise mechanisms in AD treatment remain unclear. This study aims to investigate the mechanism of DSS in treating AD by inhibiting neuronal ferroptosis, explore whether DSS alleviates AD by suppressing neuronal ferroptosis via the AMPK/Sp1/ACSL4 pathway.

Methods

Chemical composition of DSS was identified by LC-MS/MS, followed by network pharmacology to predict targets and pathways. Molecular docking assessed binding affinities between DSS compounds and key proteins (AMPK, Sp1, ACSL4). In vivo experiments on APP/PS1 mice evaluated DSS effects on cognitive function, oxidative stress markers, lipid peroxidation, and ferroptosis-related proteins.

Results

Network pharmacology analysis suggested that DSS regulates lipid metabolism and inhibits neuronal ferroptosis via the AMPK pathway. Molecular docking revealed strong binding affinities between DSS compounds and AMPK downstream proteins, Sp1 and ACSL4. In vivo experiments showed that DSS improved cognitive function, enhanced antioxidant capacity, reduced lipid peroxide accumulation, and decreased Fe2+ content in brain tissue. Furthermore, DSS increased the expression of FTH, p-AMPK, and GPX4 while decreasing Sp1 and ACSL4 levels, thereby inhibiting ferroptosis.

Conclusion

DSS alleviates AD symptoms by suppressing neuronal ferroptosis via the AMPK/Sp1/ACSL4 axis, representing a novel lipid metabolism-targeted therapeutic strategy.

Ferroptosis: when metabolism meets cell death

We present here a comprehensive update on recent advancements in the field of ferroptosis, with a particular emphasis on its metabolic underpinnings and physiological impacts. After briefly introducing landmark studies that have helped to shape the concept of ferroptosis as a distinct form of cell death, we critically evaluate the key metabolic determinants involved in its regulation. These include the metabolism of essential trace elements such as selenium and iron; amino acids such as cyst(e)ine, methionine, glutamine/glutamate, and tryptophan; and carbohydrates, covering glycolysis, the citric acid cycle, the electron transport chain, and the pentose phosphate pathway. We also delve into the mevalonate pathway and subsequent cholesterol biosynthesis, including intermediate metabolites like dimethylallyl pyrophosphate, squalene, coenzyme Q (CoQ), vitamin K, and 7-dehydrocholesterol, as well as fatty acid and phospholipid metabolism, including the biosynthesis and remodeling of ester and ether phospholipids and lipid peroxidation. Next, we highlight major ferroptosis surveillance systems, specifically the cyst(e)ine/glutathione/glutathione peroxidase 4 axis, the NAD(P)H/ferroptosis suppressor protein 1/CoQ/vitamin K system, and the guanosine triphosphate cyclohydrolase 1/tetrahydrobiopterin/dihydrofolate reductase axis. We also discuss other potential anti- and proferroptotic systems, including glutathione S-transferase P1, peroxiredoxin 6, dihydroorotate dehydrogenase, glycerol-3-phosphate dehydrogenase 2, vitamin K epoxide reductase complex subunit 1 like 1, nitric oxide, and acyl-CoA synthetase long-chain family member 4. Finally, we explore ferroptosis's physiological roles in aging, tumor suppression, and infection control, its pathological implications in tissue ischemia-reperfusion injury and neurodegeneration, and its potential therapeutic applications in cancer treatment. Existing drugs and compounds that may regulate ferroptosis in vivo are enumerated.

Warm-ischemia and cold storage induced modulation of ferroptosis observed in human hearts donated after circulatory death and brain death

We investigated ferroptosis, a type of programmed cell death mechanism, in human hearts donated after brain death (DBD) and those donated after circulatory death (DCD), focusing on warm ischemia time (WIT) and cold storage. A total of 24 hearts were procured, with six from the DBD group and 18 from the DCD group. The DCD group was divided into three subgroups, each containing six hearts, based on different WITs of 20, 40, and 60 min. All procured hearts were placed in cold storage for up to 6 h. Left ventricular biopsies were performed at 0, 2, 4, and 6 h. We measured ferroptosis regulators [glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long chain family member 4 (ACSL4), and transferrin receptor], iron content (Fe2+ and Fe3+), and lipid peroxidation (malondialdehyde, MDA) in the cardiac tissue. Modulation of ferroptosis was observed in both DBD and DCD hearts. Warm ischemia injury increased myocardial vulnerability to ferroptotic cell death. For DBD hearts, up to 6 h of cold storage increases cardiac levels of MDA, iron content, and ACSL4, thereby increasing vulnerability to ferroptotic cell death. In contrast, for DCD hearts with a WIT of 40 min or more, warm ischemia injury was identified as the primary factor contributing to increased myocardial susceptibility to ferroptotic cell death. Ferroptosis may serve as a promising target to optimize cold preservation for DBD hearts. For DCD hearts, strategies to inhibit ferroptosis should focus on the early warm ischemia phase to assess donor heart quality and suitability for transplantation.NEW & NOTEWORTHY The first human heart research explored the effects of ischemia on the myocardial ferroptotic cell death mechanism. Prolonged cold storage increases the susceptibility of DBD hearts to ferroptotic cell death. In contrast, warm ischemic injury appears to be the main factor leading to the vulnerability of DCD heart ferroptosis. Targeting ferroptosis could be beneficial in optimizing cold preservation for DBD hearts. However, for DCD hearts, interventions should focus on the early phase of warm ischemia.

Mechanisms and preventive measures of ALDH2 in ischemia‑reperfusion injury: Ferroptosis as a novel target (Review)

Ischemia‑reperfusion injury (IRI) refers to tissue or organ damage that occurs following a period of inadequate blood supply (ischemia) followed by restoration of blood flow (reperfusion) within a short time frame. This phenomenon is prevalent in clinical conditions such as cardiovascular and cerebrovascular disease, organ transplantation and stroke. Despite its frequency, effective therapeutic strategies to mitigate IRI remain elusive in clinical practice, underscoring the need for a deeper understanding of its molecular mechanisms. Aldehyde dehydrogenase 2 (ALDH2), a key enzyme in alcohol metabolism, serves a role in alleviating oxidative stress and cell damage during IRI by modulating oxidative stress, decreasing apoptosis and inhibiting inflammatory responses. ALDH2 exerts protective effects by detoxifying reactive aldehydes, thereby preventing lipid peroxidation and maintaining cellular homeostasis. Furthermore, ferroptosis, a regulated form of cell death driven by iron accumulation and subsequent lipid peroxidation, is a key process in IRI. However, the precise role of ALDH2 in modulating ferroptosis during IRI remains incompletely understood. Although there is an interaction between ALDH2 activity and ferroptosis, the underlying mechanisms have yet to be clarified. The present review examines the role of ALDH2 and ferroptosis in IRI and the potential regulatory influence of ALDH2 on ferroptosis mechanisms, as well as potential targeting of ALDH2 and ferroptosis for IRI treatment and prevention. By elucidating the complex interplay between ALDH2 and ferroptosis, the present review aims to provide new insights for the development of innovative therapeutic strategies to mitigate ischemic tissue damage and improve clinical outcomes.

The role of ACSL4 in stroke: mechanisms and potential therapeutic target

Stroke, as a neurological disorder with a poor overall prognosis, has long plagued the patients. Current stroke therapy lacks effective treatments. Ferroptosis has emerged as a prominent subject of discourse across various maladies in recent years. As an emerging therapeutic target, notwithstanding its initial identification in tumor cells associated with brain diseases, it has lately been recognized as a pivotal factor in the pathological progression of stroke. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is a potential target and biomarker of catalytic unsaturated fatty acids mediating ferroptosis in stroke. Specifically, the upregulation of ACSL4 leads to heightened accumulation of lipid peroxidation products and reactive oxygen species (ROS), thereby exacerbating the progression of ferroptosis in neuronal cells. ACSL4 is present in various tissues and involved in multiple pathways of ferroptosis. At present, the pharmacological mechanisms of targeting ACSL4 to inhibit ferroptosis have been found in many drugs, but the molecular mechanisms of targeting ACSL4 are still in the exploratory stage. This paper introduces the physiopathological mechanism of ACSL4 and the current status of the research involved in ferroptosis crosstalk and epigenetics, and summarizes the application status of ACSL4 in modern pharmacology research, and discusses the potential application value of ACSL4 in the field of stroke.

Ferroptosis spreads to neighboring cells via plasma membrane contacts

Ferroptosis is a lytic, iron-dependent form of regulated cell death characterized by excessive lipid peroxidation and associated with necrosis spread in diseased tissues through unknown mechanisms. Using a novel optogenetic system for light-driven ferroptosis induction via degradation of the anti-ferroptotic protein GPX4, we show that lipid peroxidation and ferroptotic death can spread to neighboring cells through their closely adjacent plasma membranes. Ferroptosis propagation is dependent on cell distance and completely abolished by disruption of α-catenin-dependent intercellular contacts or by chelation of extracellular iron. Remarkably, bridging cells with a lipid bilayer or increasing contacts between neighboring cells enhances ferroptosis spread. Reconstitution of iron-dependent spread of lipid peroxidation between pure lipid, contacting liposomes provides evidence for the physicochemical mechanism involved. Our findings support a model in which iron-dependent lipid peroxidation propagates across proximal plasma membranes of neighboring cells, thereby promoting the transmission of ferroptotic cell death with consequences for pathological tissue necrosis spread.

OSGEP, A Negative Ferroptotic Regulator, Alleviates Cerebral Ischemia-Reperfusion Injury Through Modulating m6A Methylation of GPX4 mRNA

Cerebral ischemia-reperfusion injury (CIRI) is a devastating condition that triggers neuronal death and cerebral infarction. O-sialoglycoprotein endopeptidase (OSGEP), identified as a crucial element of the highly conserved KEOPS complex, regulated cellular proliferation and mitochondrial metabolism. Despite its known role in cellular homeostasis, the potential contribution of OSGEP to the development of CIRI remains elusive. This study was designed to investigate the potential role of ferroptosis in the pathogenesis of CIRI and indicate whether OSGEP could suppress ferroptosis to alleviate CIRI by modulating GPX4 m6A methylation. To this end, MCAO and OGD/R models were employed to closely simulate the CIRI. The potent ferroptosis inhibitors conferred prominent neuroprotection in both in vivo and in vitro models. Moreover, OSGEP expression level was not only downregulated in MCAO-treated mice and in cultured cerebrocortical neurons subjected to OGD/R, but also it was related to the prognosis of acute ischemic stroke (AIS) cases. Additionally, OSGEP overexpression exerted potent anti-ferroptotic effects in both MCAO and OGD/R models, while OSGEP depletion exhibited the opposite effect. Moreover, OSGEP regulated GPX4 expression by modulating m6A methylation of its mRNA. Furthermore, the inhibitory effect of OSGEP on ferroptosis was dependent on the presence of GPX4. Specifically, OSGEP knockout exacerbated ferroptosis-like cell death under MCAO condition. Besides, OSGEP regulated GPX4 mRNA stability through competition with YTHDC1 for binding to GPX4 mRNA and forming a complex with HNRNPUL1 in the neuronal primary cultures subjected to OGD/R. These findings highlighted the critical role of OSGEP, as a new contributing anti-ferroptotic factor, in the pathogenesis of CIRI.

PTEN: a new dawn in Parkinson's disease treatment

In recent years, the study of phosphatase and tension homolog (PTEN) has gradually become a research hotspot. As an important oncogene, the role of PTEN in cancer has long been widely recognized and intensively studied, but it has been relatively less studied in other diseases. Parkinson's disease (PD) is a neurodegenerative refractory disease commonly observed in middle-aged and elderly individuals. The etiology and pathogenesis of PD are numerous, complex, and incompletely understood. With the continuous deepening of research, numerous studies have proven that PTEN is related to the occurrence of PD. In this review, we discuss the relationship between PTEN and PD through the phosphorylation and ubiquitination of PTEN and other possible regulatory mechanisms, including the role of RNA molecules, exosomes, transcriptional regulation, chemical modification, and subtype variation, with the aim of clarifying the regulatory role of PTEN in PD and better elucidating its pathogenesis. Finally, we summarize the shortcomings of PTEN in PD research and highlight the great potential of its future application in PD clinical treatment. These findings provide research ideas and new perspectives for the possible use of PTEN as a PD therapeutic target for targeted drug development and clinical application in the future.

Adipocyte-derived ferroptotic signaling mitigates obesity

Ferroptosis is characterized as an iron-dependent and lipophilic form of cell death. However, it remains unclear what role ferroptosis has in adipose tissue function and activity. Here, we find a lower ferroptotic signature in the adipose tissue of individuals and mice with obesity. We further find that activation of ferroptotic signaling by a non-lethal dose of ferroptosis agonists significantly reduces lipid accumulation in primary adipocytes and high-fat diet (HFD)-fed mice. Notably, adipocyte-specific overexpression of acyl-coenzyme A synthetase long-chain family member 4 (Acsl4) or deletion of ferritin heavy chain (Fth) protects mice from HFD-induced adipose expansion and metabolic disorders via activation of ferroptotic signaling. Mechanistically, we find that 5,15-dihydroxyeicosatetraenoic acid (5,15-DiHETE) activates ferroptotic signaling, resulting in the degradation of hypoxia-inducible factor-1α (HIF1α), thereby derepressing a thermogenic program regulated by the c-Myc-peroxisome proliferator-activated receptor gamma coactivator-1 beta (Pgc1β) pathway. Our findings suggest that activating ferroptosis signaling in adipose tissues might help to prevent and treat obesity and its related metabolic disorders.

TRPV4 as a Novel Regulator of Ferroptosis in Colon Adenocarcinoma: Implications for Prognosis and Therapeutic Targeting

BACKGROUND

Colon adenocarcinoma (COAD) is a leading cause of cancer-related mortality worldwide. Transient receptor potential vanilloid 4 (TRPV4), a calcium-permeable non-selective cation channel, has been implicated in various cancers, including COAD. This study investigates the role of TRPV4 in colon adenocarcinoma and elucidates its potential mechanism via the ferroptosis pathway.

MATERIALS AND METHODS

Gene expression profiles and clinical data were obtained from The Cancer Genome Atlas (TCGA), encompassing 647 colon adenocarcinoma tissue samples and 51 normal colorectal tissue samples. Ferroptosis-related genes were retrieved from the FerrDb database. Differential expression analysis, survival analysis, and Cox proportional hazards regression were performed to assess the prognostic significance of TRPV4. Protein-protein interaction networks and gene enrichment analyses (GO and KEGG) were conducted to explore functional associations. In vitro experiments were carried out using HT-29 and SW480 colon cancer cell lines. TRPV4 was knocked down using siRNA, and cell viability was assessed via hematoxylin and eosin (HE) staining. Immunofluorescence assays evaluated the expression of ferroptosis-related proteins (SLC3A2, GPX4) and proliferation markers (KI67, SRC, CTNNB1, COL1).

RESULTS

TRPV4 expression was significantly elevated in colon adenocarcinoma tissues compared to normal tissues (p < 0.05), demonstrating high diagnostic accuracy (AUC = 0.848). High TRPV4 expression correlated with poorer overall survival (OS) and disease-specific survival (DSS), particularly in patients over 65 years old and those in clinical stage II. Cox regression analysis confirmed TRPV4 as an independent prognostic factor (HR = 1.395, p = 0.074). Bioinformatics analyses revealed that TRPV4 is closely associated with ferroptosis-related genes, participating in key biological processes such as responses to external stimuli, oxidative stress, and cell adhesion. In vitro, TRPV4 knockdown significantly reduced cell viability (p < 0.05) and decreased expression levels of SLC3A2, GPX4, KI67, SRC, and COL1 (p < 0.05). The addition of the ferroptosis inhibitor FER-1 did not restore cell viability in TRPV4 knockdown cells, suggesting that TRPV4 modulates cell survival through the ferroptosis pathway.

DISCUSSION

The bioinformation and in vitro experiments inTRPV4 and ferroptosis-related genes support the hypothesis that TRPV4 influences tumor cell survival via the ferroptosis pathway. The inability of FER-1 to rescue viability in TRPV4-deficient cells further confirms this mechanism. These findings provide novel insights into the molecular mechanisms of COAD and highlight TRPV4 as a potential therapeutic target.

CONCLUSION

TRPV4 is significantly upregulated in COAD and is associated with unfavorable patient outcomes. It appears to promote tumor progression by regulating the ferroptosis pathway, affecting the expression of key ferroptosis-related genes and proliferation markers. Targeting TRPV4 may offer a new therapeutic approach for COAD, and further research is warranted to explore its role in other cancers and to develop TRPV4-based therapies.

Parkin inhibits iron overload-induced cardiomyocyte ferroptosis by ubiquitinating ACSL4 and modulating PUFA-phospholipids metabolism

Iron overload is strongly associated with heart disease. Ferroptosis is a new form of regulated cell death indicated in cardiac ischemia-reperfusion (I/R) injury. However, the specific molecular mechanism of myocardial injury caused by iron overload in the heart is still unclear, and the involvement of ferroptosis in iron overload-induced myocardial injury is not fully understood. In this study, we observed that ferroptosis participated in developing of iron overload and I/R-induced cardiomyopathy. Mechanistically, we discovered that Parkin inhibited iron overload-induced ferroptosis in cardiomyocytes by promoting the ubiquitination of long-chain acyl-CoA synthetase 4 (ACSL4), a crucial protein involved in ferroptosis-related lipid metabolism pathways. Additionally, we identified p53 as a transcription factor that transcriptionally suppressed Parkin expression in iron-overloaded cardiomyocytes, thereby regulating iron overload-induced ferroptosis. In animal studies, cardiac-specific Parkin knockout mice (Myh6-CreER T2 /Parkin fl/fl ) fed a high-iron diet presented more severe myocardial damage, and the high iron levels exacerbated myocardial I/R injury. However, the ferroptosis inhibitor Fer-1 significantly suppressed iron overload-induced ferroptosis and myocardial I/R injury. Moreover, Parkin effectively protected against impaired mitochondrial function and prevented iron overload-induced mitochondrial lipid peroxidation. These findings unveil a novel regulatory pathway involving p53-Parkin-ACSL4 in heart disease by inhibiting of ferroptosis.

Piceatannol upregulates USP14-mediated GPX4 deubiquitination to inhibit neuronal ferroptosis caused by cerebral ischemia-reperfusion in mice

Ischemic stroke is a very common brain disorder. This study aims to assess the neuroprotective effects of piceatannol (PCT) in preventing neuronal injury resulting from cerebral ischemia and reperfusion (I/R) in mice. Additionally, we investigated the underlying mechanisms through which PCT inhibits neuronal ferroptosis by modulating the USP14/GPX4 signaling axis. In vitro and in vivo experiments were conducted. In vitro, oxygen-glucose deprivation followed by reoxygenation (OGD/R) was used to simulate ischemic injury in neuronal cells. We utilized various techniques, including DCFH-DA staining, FeRhoNox-1 staining, MDA and GSH determination, immunofluorescence, Western blotting, co-immunoprecipitation, plasmid and siRNA transfection, to evaluate the therapeutic efficacy of PCT and elucidate its mechanism of action. For vivo studies, we established a mouse model of I/R by ligating the bilateral common carotid arteries. The efficacy of PCT in mitigating brain injury and cognitive dysfunction were assessed through behavioral tests, histological analysis, Western blotting, and immunohistochemistry. PCT treatment significantly enhanced cell viability under OGD/R and reduced lipid peroxidation by decreasing levels of ROS, MDA. Furthermore, PCT effectively inhibited neuronal ferroptosis by modulating the expression of key ferroptosis-related proteins, including GPX4, ACSL4, FPN1, and Ferritin. Mechanistically, PCT was found to prevent GPX4 degradation through USP14-mediated deubiquitination. Notably, silencing USP14 reversed the ferroptotic effects of PCT, whereas overexpressing of USP14 amplified these effects. In vivo, PCT significantly reduced pathological damage of brain tissue and improved cognitive dysfunction. Piceatannol exerts neuroprotective effects by regulating ferroptosis through the USP14/GPX4 axis, thereby preventing cerebral ischemia/reperfusion injury.

KLF9, Epigenetic Silenced by DNMT1, Promotes ERK-Mediated Ferroptosis of Osteoarthritic Chondrocytes Through Transcriptionally Regulating CYP1B1

Ferroptosis plays a crucial role in the pathogenesis of osteoarthritis (OA), and inhibition of chondrocyte ferroptosis effectively alleviates OA progression. Krüppel-like factor 9 (KLF9) is demonstrated to be upregulated in OA, but its molecular mechanism remains unclear. The study aimed to investigate the role of KLF9 in OA progression. Primary chondrocytes were treated with IL-1β to establish an OA cell model, and showed that KLF9 was highly expressed in IL-1β-incubated chondrocytes. Knockdown of KLF9 alleviated IL-1β-induced chondrocyte degeneration. In addition, chondrocytes treated with IL-1β showed a decreased methylation proportion in the KLF9 gene promoter. DNA methyltransferase 1 (DNMT1) directly bound to the KLF9 promoter, and overexpression of DNMT1 inhibited KLF9 expression by promoting its promoter methylation in chondrocytes. Subsequently, KLF9 shRNA and pcDNA-CYP1B1 were individually or altogether transfected into chondrocytes. KLF9 shRNA inhibited Cytochrome P450 1B1 (CYP1B1) expression in chondrocytes, and pcDNA-CYP1B1 abrogated the inhibitory effect of KLF9 shRNA on IL-1β-induced chondrocyte ferroptosis. Moreover, Ferrostatin-1 (Fer-1, an inhibitor of ferroptosis) reversed the promotion of pcDNA-CYP1B1 on IL-1β-induced chondrocyte ferroptosis. Finally, in vivo experiments showed that KLF9 shRNA significantly suppressed the cartilage tissue damage, ferroptosis, and the IHC scores of KLF9 and CYP1B1 in rats. In conclusion, our results suggested that KLF9, epigenetic silenced by DNMT1, promoted extracellular signal-regulated kinase (ERK)-mediated ferroptosis of OA chondrocytes through transcriptionally regulating CYP1B1. Thus, KLF9 is expected to be a new target for the treatment of OA.

Extracellular matrix gene set and microRNA network in intestinal ischemia-reperfusion injury: Insights from RNA sequencing for diagnosis and therapy

Intestinal ischemia-reperfusion injury (IIRI) is a complex and severe pathophysiological process characterized by oxidative stress, inflammation, and apoptosis. In recent years, the critical roles of extracellular matrix (ECM) genes and microRNAs (miRNAs) in IIRI have garnered widespread attention. This review aims to systematically summarize the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI. First, we review the molecular mechanisms of IIRI, focusing on the dual role of the ECM in tissue injury and repair processes. The expression changes and functions of ECM components such as collagen, elastin, and matrix metalloproteinases during IIRI progression are deeply analyzed. Second, we systematically summarize the regulatory roles of miRNAs in IIRI, particularly the mechanisms and functions of miRNAs such as miR-125b and miR-200a in regulating inflammation, apoptosis, and ECM remodeling. Additionally, this review discusses potential diagnostic biomarkers and treatment strategies based on ECM genes and miRNAs. We extensively evaluate the prospects of miRNA-targeted therapy and ECM component modulation in preventing and treating IIRI, emphasizing the clinical translational potential of these emerging therapies. In conclusion, the diagnostic and therapeutic potential of ECM gene sets and miRNA regulatory networks in IIRI provides new directions for further research, necessitating additional clinical and basic studies to validate and expand these findings for improving clinical outcomes in IIRI patients.

Terahertz Wave Desensitizes Ferroptosis by Inhibiting the Binding of Ferric Ions to the Transferrin

Ferroptosis is a classic type of programmed cell death characterized by iron dependence, which is closely associated with many diseases such as cancer, intestinal ischemic diseases, and nervous system diseases. Transferrin (Tf) is responsible for ferric-ion delivery owing to its natural Fe3+ binding ability and plays a crucial role in ferroptosis. However, Tf is not considered as a classic druggable target for ferroptosis-associated diseases since systemic perturbation of Tf would dramatically disrupt blood iron homeostasis. Here, we reported a nonpharmaceutical, noninvasive, and Tf-targeted electromagnetic intervention technique capable of desensitizing ferroptosis with directivity. First, we revealed that the THz radiation had the ability to significantly decrease binding affinity between the Fe3+ and Tf via molecular dynamics simulations, and the modulation was strongly wavelength-dependent. This result provides theoretical feasibility for the THz modulation-based ferroptosis intervention. Subsequent extracellular and cellular chromogenic activity assays indicated that the THz field at 8.7 μm (i.e., 34.5 THz) inhibited the most Fe3+ bound to the Tf, and the wavelength was in good agreement with the simulated one. Then, functional assays demonstrated that levels of intracellular Fe2+, lipid peroxidation, malondialdehyde (MDA) and cell death were all significantly reduced in cells treated with this 34.5 THz wave. Furthermore, the iron deposition, lipid peroxidation, and MDA in the ferroptosis disease model induced by ischemia-reperfusion injury could be nearly eliminated by the same radiation, validating THz wave-induced desensitization of ferroptosis in vivo. Together, this work provides a preclinical exemplar for electromagnetic irradiation-stimulated desensitization of ferroptosis and predicts an innovative, THz wave-based therapeutic method for ferroptosis-associated diseases in the future.

Harnessing ferroptosis for precision oncology: challenges and prospects

The discovery of diverse molecular mechanisms of regulated cell death has opened new avenues for cancer therapy. Ferroptosis, a unique form of cell death driven by iron-catalyzed peroxidation of membrane phospholipids, holds particular promise for targeting resistant cancer types. This review critically examines current literature on ferroptosis, focusing on its defining features and therapeutic potential. We discuss how molecular profiling of tumors and liquid biopsies can generate extensive multi-omics datasets, which can be leveraged through machine learning-based analytical approaches for patient stratification. Addressing these challenges is essential for advancing the clinical integration of ferroptosis-driven treatments in cancer care.

FADS1 inhibition protects retinal pigment epithelium cells from ferroptosis in age related macular degeneration

PURPOSE

Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly individuals. Retinal pigment epithelium (RPE) ferroptosis is a significant pathogenetic component in AMD. This study aims to elucidate the role and mechanisms of fatty acid desaturase 1 (FADS1) in ferroptosis as well as AMD progression.

METHODS

An integrated bioinformatics analysis based on the array of data from the GEO database was conducted to identify candidates involved in ferroptosis during AMD. Subsequently, cellular and mouse models of AMD were developed using sodium iodate (NaIO3) to confirm the altered expression of FADS1. After treatment with a FADS1 inhibitor, cell survival, lipid peroxidation, and indicators of AMD were assessed in vitro and in vivo models. Further, immunofluorescence, immunohistochemistry, and swept-source OCT imaging were performed to assess the impacts of pharmacological inhibition of transcription factor specificity protein 1 (Sp1) on FADS1 and ferroptosis.

RESULTS

FADS1 expression was upregulated in AMD patients and in vitro and in vivo models of AMD. Its pharmacological inhibition had decreased mitochondrial ROS formation, lipid peroxidation, and ferroptosis as well as increased RPE cell function in ARPE-19 cells and C57BL/6J mouse models of AMD. Mechanistically, Sp1 was identified as a key transcription factor of FADS1. Moreover, Sp1 inhibition downregulated FADS1 expression consequently attenuating FADS1-mediated ferroptosis as well as AMD phenotypes.

CONCLUSION

For the first time, we demonstrated that Sp1 regulates FADS1-mediated ferroptosis in RPE cells. Our findings provide novel insights into the progression and treatment of AMD.

Targeting Ferroptosis in Parkinson's: Repurposing Diabetes Drugs as a Promising Treatment

This review explores the promising potential of repurposing type 2 diabetes (T2D) medications for the treatment of Parkinson's disease (PD), highlighting the shared pathophysiological mechanisms between these two age-related conditions, such as oxidative stress, mitochondrial dysfunction, and ferroptosis. The overlap suggests that existing diabetes drugs could target the common pathways involved in both conditions. Specifically, the review discusses how T2D medications, including metformin (Met), peroxisome-proliferator-activated receptor gamma (PPAR-γ) agonists, sodium-glucose cotransporter-2 (SGLT2) inhibitors, incretins, and dipeptidyl-peptidase 4 (DPP-4) inhibitors, can improve mitochondrial function, reduce neuroinflammation and oxidative stress, and potentially inhibit ferroptosis. The connection between ferroptosis and existing treatments, including diabetes medication, are only beginning to be explored. The limited data can be attributed also to the complexity of mechanisms involved in ferroptosis and Parkinson's disease and to the fact that the specific role of ferroptosis in Parkinson's disease pathogenesis has not been a primary focus until recent. Despite the promising preclinical evidence, clinical findings are mixed, underscoring the need for further research to elucidate these drugs' roles in neurodegeneration. Repurposing existing diabetes medications that have well-established safety profiles for Parkinson's disease treatment could significantly reduce the time and cost associated with drug development and could offer a more comprehensive approach to managing Parkinson's disease compared to treatments targeting a single mechanism.

Ubiquitin-specific peptidase 14 promotes neuron injury by stabilizing acyl-CoA synthetase long-chain family member 4 through deubiquitination

Objective

Ubiquitin-specific peptidase 14 (USP14) may be a target for stroke treatment. Our study aims to explore the molecular mechanism of USP14 in the stroke process.

Material and Methods

A stroke cell model was constructed using oxygen-glucose deprivation/reoxygenation (OGD/R)-induced SK-N-SH cells, and cell growth was assessed using cell counting kit 8 assay, EdU assay, and flow cytometry. Proinflammatory cytokine levels were tested through an enzyme-linked immunosorbent assay. The levels of USP14 and acyl-CoA synthetase long-chain family member 4 (ACSL4) were determined through Western blot and quantitative real-time polymerase chain reaction, whereas the interaction of USP14 and ACS14 was evaluated by co-immunoprecipitation assay.

Results

OGD/R-induced SK-N-SH cell injury by enhancing ferroptosis and the knockdown of USP14 inhibited OGD/R-induced cell inflammation, apoptosis, and ferroptosis. Moreover, USP14 enhanced ACSL4 protein expression through deubiquitination. ACSL4 silencing mitigated neuron injury, and ACSL4 upregulation abolished USP14 knockdown-mediated inhibition of neuron injury.

Conclusion

USP14 can enhance neuron injury through stabilizing ACSL4 protein expression.

Iron and ferroptosis in kidney disease: molecular and metabolic mechanisms

Maintaining iron homeostasis is necessary for kidney functioning. There is more and more research indicating that kidney disease is often caused by iron imbalance. Over the past decade, ferroptosis' role in mediating the development and progression of renal disorders, such as acute kidney injury (renal ischemia-reperfusion injury, drug-induced acute kidney injury, severe acute pancreatitis induced acute kidney injury and sepsis-associated acute kidney injury), chronic kidney disease (diabetic nephropathy, renal fibrosis, autosomal dominant polycystic kidney disease) and renal cell carcinoma, has come into focus. Thus, knowing kidney iron metabolism and ferroptosis regulation may enhance disease therapy. In this review, we discuss the metabolic and molecular mechanisms of iron signaling and ferroptosis in kidney disease. We also explore the possible targets of ferroptosis in the therapy of renal illness, as well as their existing limitations and future strategies.

O-GlcNAcylation attenuates ischemia-reperfusion-induced pulmonary epithelial cell ferroptosis via the Nrf2/G6PDH pathway

BACKGROUND

Lung ischemia-reperfusion (I/R) injury is a common clinical pathology associated with high mortality. The pathophysiology of lung I/R injury involves ferroptosis and elevated protein O-GlcNAcylation levels, while the effect of O-GlcNAcylation on lung I/R injury remains unclear. This research aimed to explore the effect of O-GlcNAcylation on reducing ferroptosis in pulmonary epithelial cells caused by I/R.

RESULTS

First, we identified O-GlcNAc transferase 1 (Ogt1) as a differentially expressed gene in lung epithelial cells of acute lung injury/acute respiratory distress syndrome (ALI/ARDS) patients, using single-cell sequencing, and Gene Ontology analysis (GO analysis) revealed the enrichment of the ferroptosis process. We found a time-dependent dynamic alteration in lung O-GlcNAcylation during I/R injury. Proteomics analysis identified the differentially expressed proteins enriched in ferroptosis and multiple redox-related pathways based on KEGG annotation. Thus, we generated Ogt1-conditional knockout mice and found that Ogt1 deficiency aggravated ferroptosis, as evidenced by lipid reactive oxygen species (lipid ROS), malondialdehyde (MDA), Fe2+, as well as alterations in critical protein expression glutathione peroxidase 4 (GPX4) and solute carrier family 7 member 11 (SLC7A11). Consistently, we found that elevated O-GlcNAcylation inhibited ferroptosis sensitivity in hypoxia/reoxygenation (H/R) injury-induced TC-1 cells via O-GlcNAcylated NF-E2-related factor-2 (Nrf2). Furthermore, both the chromatin immunoprecipitation (ChIP) assay and the dual-luciferase reporter assay indicated that Nrf2 could bind with translation start site (TSS) of glucose-6-phosphate dehydrogenase (G6PDH) and promote its transcriptional activity. As an important rate-limiting enzyme in the pentose phosphate pathway (PPP), elevated G6PDH provided a mass of nicotinamide adenine dinucleotide phosphate (NADPH) to improve the redox state of glutathione (GSH) and eventually led to ferroptosis resistance. Rescue experiments proved that Nrf2 knockdown or Nrf2-T334A (O-GlcNAcylation site) mutation abolished the protective effect of ferroptosis resistance.

CONCLUSIONS

In summary, we revealed that O-GlcNAcylation could protect against I/R lung injury by reducing ferroptosis sensitivity via the Nrf2/G6PDH pathway. Our work will provide a new basis for clinical therapeutic strategies for pulmonary ischemia-reperfusion-induced acute lung injury.

N-Acetylcysteine Alleviates Necrotizing Enterocolitis by Depressing SESN2 Expression to Inhibit Ferroptosis in Intestinal Epithelial Cells

Abstract-Necrotizing enterocolitis (NEC) is a severe gastrointestinal disease in neonates, and effective strategies to prevent and treat NEC are still lacking. Studies have shown that N-acetylcysteine (NAC) has protective effects against NEC, however, the specific mechanism underlying its effects on intestinal functions remains unclear. Recently, NAC has been shown to suppress ferroptosis in many diseases, while it is unclear whether the beneficial effects of NAC on NEC are related to ferroptosis. In this study, we revealed that ferroptosis was significantly induced in intestinal samples from infants with NEC. NAC alleviated intestinal inflammation, barrier damage and ferroptosis in multifactorial NEC models in vivo and in vitro. Sestrin2 (SESN2) was identified as an important mediator of NAC-induced ferroptosis resistance in intestinal epithelial cells. Furthermore, SESN2 knockdown inhibited the inflammatory response, alleviated barrier damage and ferroptosis in intestinal epithelial cells and enhanced the protective effects of NAC to a certain extent. Conversely, cells overexpressing SESN2 showed the opposite changes. In summary, our study demonstrated that NAC attenuates NEC progression by decreasing SESN2 expression to inhibit ferroptosis in intestinal epithelial cells, suggesting that NAC might be an effective clinical treatment for NEC.

High Concentration of Iron Ions Contributes to Ferroptosis-Mediated Testis Injury

In order to explore the effect of excessive iron supplementation on ferroptosis in mouse testes, Kunming mice received injections of varying concentrations of iron. The organ weight, sperm density, and malformation rate were measured. Observations of pathological and ultrastructural alterations in spermatogenic tubules were conducted using haematoxylin eosin (HE) staining and transmission electron microscopy(TEM). Transcript levels of related genes and serum biochemical indicators were measured in mouse testicular tissue. The results showed that higher iron concentration inhibited the growth of mice; reduced the organ coefficients of the testis, heart, and liver; and increased the rate of sperm malformation and mortality. Supplementation with high levels of iron ions can adversely affect the male reproductive system by reducing sperm count, damaging the structure of the seminiferous tubules and causing sperm cell abnormalities. In addition, the iron levels also affected the immune response and blood coagulation ability by affecting the red blood cells, white blood cells and platelets. The results showed that iron ions can affect mouse testicular tissue and induce ferroptosis by altering the expression of ferroptosis-related genes. However, the degree of effect was different for the different concentrations of iron ions. The study also revealed the potential role of deferoxamine in inhibiting the occurrence of ferroptosis. Nevertheless, the damage caused to the testis by deferoxamine supplementation suggests the need for further research in this direction. This study provides reference for reproductive toxicity induced by environmental iron exposure and clarifies the mechanism of reproductive toxicity caused by iron overload and the important role of iron in the male reproductive system.