Mitochondrial general control of amino acid synthesis 5 like 1 promotes nonalcoholic steatohepatitis development through ferroptosis-induced formation of neutrophil extracellular traps

TRIM21 knockdown alleviates hemorrhage induced hepatic ischemia reperfusion injury by suppressing ferroptosis-induced NETs

Hemorrhage-induced hepatic ischemia/reperfusion (I/R) injury is a severe complication of hemorrhagic shock, yet its molecular mechanisms remain unclear. The aim of this study was to investigate the potential mechanism of action of TRIM21 on hemorrhage-induced hepatic I/R injury. The role of TRIM21 in hepatic I/R injury was evaluated by establishing a mouse model of hemorrhage-induced hepatic I/R injury and an in vitro simulated oxygen-glucose deprivation/reoxygenation (OGD/R) hepatocyte injury model. A comprehensive analysis was conducted, including histopathological changes, serum biochemical indicators, inflammatory cytokine levels, markers of neutrophil extracellular trap (NETs) formation, and biomarkers related to ferroptosis, such as the expression of iron metabolism-related proteins SLC7A11 and FTH1, oxidative stress and antioxidant capacity, NETs formation markers (Cit-H3, PAD4, and MPO), and the expression levels of TRIM21.The study revealed that ferroptosis-induced NETs was involved in the process of hepatic I/R injury, concurrent with elevated serum ALT and AST levels and increased cell apoptosis. In the hemorrhage-induced hepatic I/R injury mouse model and OGD/R-induced hepatocyte injury, the expression of TRIM21 is significantly upregulated. Knockdown of TRIM21 can effectively inhibit the formation of ferroptosis-induced NETs, thereby alleviating hepatic I/R injury. In terms of the underlying mechanism, TRIM21 promotes the formation of ferroptosis-induced NETs by regulating the stability of the SLC7A11 protein, thus exacerbating hepatic I/R injury. The study discovered that silencing TRIM21 inhibits ferroptosis-mediated NETs formation by ubiquitinating SLC7A11, effectively alleviating hepatic I/R injury. This discovery may provide a potential therapeutic strategy for the treatment of hemorrhage-induced hepatic I/R injury.

Lipotoxicity, lipid peroxidation and ferroptosis: a dilemma in cancer therapy

The vulnerability of tumor cells to lipid peroxidation, driven by redox imbalance and lipid overabundance within the tumor microenvironment (TME), has become a focal point for novel antitumor strategies. Ferroptosis, a form of regulated cell death predicated on lipid peroxidation, is emerging as a promising approach. Beyond their role in directly eliminating tumor cells, lipid peroxidation and its products, such as 4-hydroxynonenal (HNE), exert an additional influence by damaging DNA and shaping an environment conducive to tumor growth and metastasis. This process polarizes macrophages towards a pro-inflammatory phenotype, dampens the antigen-presenting capacity of dendritic cells (DCs), and undermines the cytotoxic functions of T and NK cells. Furthermore, it transforms neutrophils into pro-tumorigenic polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs). The lipid peroxidation of stroma cells also contributes to tumor progression. Although advanced nanotherapies have shown the ability to target tumor cells precisely, they often overlook the nuanced effects of lipid peroxidation products. In this review, we highlight a synergistic mechanism in which lipid peroxidation products and ferroptosis contribute to an immunosuppressive state that is temporally distinct from cell death. This insight broadens our understanding of ferroptosis-derived immunosuppression, encompassing all types of immune cells within the TME. This review aims to catalyze further research in this underexplored area, emphasizing the potential of lipid peroxidation products to hinder the clinical translation of ferroptosis-based therapies.

Neutrophil extracellular traps in tumor metabolism and microenvironment

Neutrophil extracellular traps (NETs) are intricate, web-like formations composed of DNA, histones, and antimicrobial proteins, released by neutrophils. These structures participate in a wide array of physiological and pathological activities, including immune rheumatic diseases and damage to target organs. Recently, the connection between NETs and cancer has garnered significant attention. Within the tumor microenvironment and metabolism, NETs exhibit multifaceted roles, such as promoting the proliferation and migration of tumor cells, influencing redox balance, triggering angiogenesis, and driving metabolic reprogramming. This review offers a comprehensive analysis of the link between NETs and tumor metabolism, emphasizing areas that remain underexplored. These include the interaction of NETs with tumor mitochondria, their effect on redox states within tumors, their involvement in metabolic reprogramming, and their contribution to angiogenesis in tumors. Such insights lay a theoretical foundation for a deeper understanding of the role of NETs in cancer development. Moreover, the review also delves into potential therapeutic strategies that target NETs and suggests future research directions, offering new perspectives on the treatment of cancer and other related diseases.

Neutrophil PPIF exacerbates lung ischemia-reperfusion injury after lung transplantation by promoting calcium overload-induced neutrophil extracellular traps formation

Lung ischemia-reperfusion (I/R) injury is the main risk factor for primary graft dysfunction and patient death after lung transplantation (LTx). It is widely accepted that the main pathological mechanism of lung I/R injury are calcium overload, oxygen free radical explosion and neutrophil-mediated damage, which leading to the lack of effective treatment options. The aim of this study was to further explore the mechanisms of lung I/R injury after LTx and to provide potential therapeutic strategies. Our bioinformatics analysis revealed that the neutrophil extracellular traps (NETs) formation was closely involved in lung I/R injury after LTx, which was accompanied by up-regulation of peptidylprolyl isomerase F (PPIF) and peptidyl arginine deiminase 4 (PADI4). We further established an orthotopic LTx mouse model to simulate lung I/R injury in vivo, and found that PPIF and PADI4 inhibitors effectively reduced neutrophil infiltration, NETs formation, inflammatory response, and lung I/R injury. In the neutrophil model induced by HL-60 cell line in vitro, we found that PPIF inhibitor cyclosporin A (Cys A) better alleviated calcium overload induced inflammatory response, reactive oxygen species content and NETs formation. Further study demonstrated that interfering with neutrophil PPIF protected mitochondrial function by alleviating store-operated calcium entry (SOCE) during calcium overload and played the above positive role. On this basis, we found that the reduction of calcium content in neutrophils was accompanied by the inhibition of calcineurin (CN) and nuclear factor of activated T cells (NFAT). In conclusion, our findings suggested that neutrophil PPIF could serve as a novel biomarker and potential therapeutic target of lung I/R injury after LTx, which provided new clues for its treatment by inhibiting calcium overload-induced NETs formation.

Ferroptosis: mechanisms and therapeutic targets

Ferroptosis is a nonapoptotic form of cell death characterized by iron-dependent lipid peroxidation in membrane phospholipids. Since its identification in 2012, extensive research has unveiled its involvement in the pathophysiology of numerous diseases, including cancers, neurodegenerative disorders, organ injuries, infectious diseases, autoimmune conditions, metabolic disorders, and skin diseases. Oxidizable lipids, overload iron, and compromised antioxidant systems are known as critical prerequisites for driving overwhelming lipid peroxidation, ultimately leading to plasma membrane rupture and ferroptotic cell death. However, the precise regulatory networks governing ferroptosis and ferroptosis-targeted therapy in these diseases remain largely undefined, hindering the development of pharmacological agonists and antagonists. In this review, we first elucidate core mechanisms of ferroptosis and summarize its epigenetic modifications (e.g., histone modifications, DNA methylation, noncoding RNAs, and N6-methyladenosine modification) and nonepigenetic modifications (e.g., genetic mutations, transcriptional regulation, and posttranslational modifications). We then discuss the association between ferroptosis and disease pathogenesis and explore therapeutic approaches for targeting ferroptosis. We also introduce potential clinical monitoring strategies for ferroptosis. Finally, we put forward several unresolved issues in which progress is needed to better understand ferroptosis. We hope this review will offer promise for the clinical application of ferroptosis-targeted therapies in the context of human health and disease.

Neutrophil extracellular trap-induced ferroptosis promotes abdominal aortic aneurysm formation via SLC25A11-mediated depletion of mitochondrial glutathione

BACKGROUND

Neutrophil extracellular traps (NETs) induce oxidative stress, which may initiate ferroptosis, an iron-dependent programmed cell death, during abdominal aortic aneurysm (AAA) formation. Mitochondria regulate the progression of ferroptosis, which is characterized by the depletion of mitochondrial glutathione (mitoGSH) levels. However, the mechanisms are poorly understood. This study examined the role of mitoGSH in regulating NET-induced ferroptosis of smooth muscle cells (SMCs) during AAA formation.

METHODS

Concentrations of NET markers were tested in plasma samples. Western blotting and immunofluorescent staining were performed to detect the expression and localization of NET and ferroptosis markers in tissue samples. The role of NETs and SMC ferroptosis during AAA formation was investigated using peptidyl arginine deiminase 4 gene (Padi4) knockout or treatment with a PAD4 inhibitor, ferroptosis inhibitor or activator in an angiotensin II-induced AAA mouse model. The regulatory effect of SLC25A11, a mitochondrial glutathione transporter, on mitoGSH and NET-induced ferroptosis of SMCs was investigated using in vitro and in vivo experiments. Transmission electron microscopy was used to detect mitochondrial damage. Blue native polyacrylamide gel electrophoresis was used to analyze the dimeric and monomeric forms of the protein.

RESULTS

Significantly elevated levels of NETosis and ferroptosis markers in aortic tissue samples were observed during AAA formation. Specifically, NETs promoted AAA formation by inducing ferroptosis of SMCs. Subsequently, SLC25A11 was identified as a potential biomarker for evaluating the clinical prognosis of patients with AAA. Furthermore, NETs decreased the stability and dimerization of SLC25A11, leading to the depletion of mitoGSH. This depletion induced the ferroptosis of SMCs and promoted AAA formation.

CONCLUSION

During AAA formation, NETs regulate the stability of the mitochondrial carrier protein SLC25A11, leading to the depletion of mitoGSH and subsequent activation of NET-induced ferroptosis of SMCs. Preventing mitoGSH depletion and ferroptosis in SMCs is a potential strategy for treating AAA.

Nets in fibrosis: Bridging innate immunity and tissue remodeling

Fibrosis, a complex pathological process characterized by excessive deposition of extracellular matrix components, leads to tissue scarring and dysfunction. Emerging evidence suggests that neutrophil extracellular traps (NETs), composed of DNA, histones, and antimicrobial proteins, significantly contribute to fibrotic diseases pathogenesis. This review summarizes the process of NETs production, molecular mechanisms, and related diseases, and outlines the cellular and molecular mechanisms associated with fibrosis. Subsequently, this review comprehensively summarizes the current understanding of the intricate interplay between NETs and fibrosis across various organs, including the lung, liver, kidney, skin, and heart. The mechanisms by which NETs contribute to fibrogenesis, including their ability to promote inflammation, induce epithelial-mesenchymal transition (EMT), activate fibroblasts, deposit extracellular matrix (ECM) components, and trigger TLR4 signaling were explored. This review aimed to provide insights into the complex relationship between NETs and fibrosis via a comprehensive analysis of existing reports, offering novel perspectives for future research and therapeutic interventions.

Targeting the regulation of iron homeostasis as a potential therapeutic strategy for nonalcoholic fatty liver disease

With aging and the increasing incidence of obesity, nonalcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease worldwide. NAFLD mainly includes simple hepatic steatosis, nonalcoholic steatohepatitis (NASH), liver fibrosis and hepatocellular carcinoma (HCC). An imbalance in hepatic iron homeostasis is usually associated with the progression of NAFLD and induces iron overload, reactive oxygen species (ROS) production, and lipid peroxide accumulation, which leads to ferroptosis. Ferroptosis is a unique type of programmed cell death (PCD) that is characterized by iron dependence, ROS production and lipid peroxidation. The ferroptosis inhibition systems involved in NAFLD include the solute carrier family 7 member 11 (SLC7A11)/glutathione (GSH)/glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1)/coenzyme Q10 (CoQ10)/nicotinamide adenine dinucleotide phosphate (NADPH) regulatory axes. The main promotion system involved is the acyl-CoA synthetase long-chain family (ACSL4)/arachidonic lipoxygenase 15 (ALOX15) axis. In recent years, an increasing number of studies have focused on the multiple roles of iron homeostasis imbalance and ferroptosis in the progression of NAFLD. This review highlights the latest studies about iron homeostasis imbalance- and ferroptosis-associated NAFLD, mainly including the physiology and pathophysiology of hepatic iron metabolism, hepatic iron homeostasis imbalance during the development of NAFLD, and key regulatory molecules and roles of hepatic ferroptosis in NAFLD. This review aims to provide innovative therapeutic strategies for NAFLD.

Role of Neutrophils in the Development of Steatotic Liver Disease

This review explores the biological aspects of neutrophils, their contributions to the development of steatotic liver disease, and their potential as therapeutic targets for the disease. Although alcohol-associated and metabolic dysfunction-associated liver diseases originate from distinct etiological factors, the two diseases frequently share excessive lipid accumulation as a common contributor to their pathogenesis, thereby classifying them as types of steatotic liver disease. Dysregulated lipid deposition in the liver induces hepatic injury, triggering the activation of the innate immunity, partially through neutrophil recruitment. Traditionally recognized for their role in microbial clearance, neutrophils have recently garnered attention for their involvement in sterile inflammation, a pivotal component of steatotic liver disease pathogenesis. In conclusion, technological innovations, including single-cell RNA sequencing, have gradually disclosed the existence of various neutrophil subsets; however, how the distinct subsets of neutrophil population contribute differentially to the development of steatotic liver disease remains unclear.

Discovery and Validation of Ferroptosis-Associated Genes of Ulcerative Colitis

Background

Ulcerative colitis (UC) is a long-lasting idiopathic condition, but its precise mechanisms remain unclear. Meanwhile, evidence has demonstrated that ferroptosis seems to interlock with the progress of UC. This research sought to identify hub genes of UC related to ferroptosis.

Methods

First, the relevant profiles for this article were obtained from GEO database. From the FerrDb, 479 genes linked to ferroptosis were retrieved. Using analysis of the difference and WGCNA on colonic samples from GSE73661, the remaining six hub genes linked to ferroptosis and UC were discovered. Through logistic regression analyses, the diagnostic model was constructed and was then evaluated by external validation using dataset GSE92415. Afterwards, the correlation between immune cell filtration in UC and hub genes was examined. Finally, a mice model of colitis was established, and the results were verified using qRT-PCR.

Results

We acquired six hub genes linked to ferroptosis and UC. In order to create a diagnostic model for UC, we used logistic regression analysis to screen three of the six ferroptosis related genes (HIF1A, SLC7A11, and LPIN1). The ROC curve showed that the three hub genes had outstanding potential for disease diagnosis (AUC = 0.976), which was subsequently validated in samples from GSE92415 (AUC = 0.962) and blood samples from GSE3365 (AUC = 0.847) and GSE94648 (AUC = 0.769). These genes might be crucial for UC immunity based upon the results on the immune system. Furthermore, mouse samples examined using qRT-PCR also verified our findings.

Conclusion

In conclusion, the findings have important implications for ferroptosis and UC, and these hub genes may also offer fresh perspectives on the aetiology and therapeutic approaches of UC.

Establishment of a Mitochondrial Metabolism-Related Diagnostic Model in Schizophrenia Based on LASSO Algorithm

OBJECTIVE

Schizophrenia is a common mental disorder, and mitochondrial function represents a potential therapeutic target for psychiatric diseases. The role of mitochondrial metabolism-related genes (MRGs) in the diagnosis of schizophrenia remains unknown. This study aimed to identify candidate genes that may influence the diagnosis and treatment of schizophrenia based on MRGs.

METHODS

Three schizophrenia datasets were obtained from the Gene Expression Omnibus database. MRGs were collected from relevant literature. The differentially expressed genes between normal samples and schizophrenia samples were screened using the limma package. Venn analysis was performed to identify differentially expressed MRGs (DEMRGs) in schizophrenia. Based on the STRING database, hub genes in DEMRGs were identified using the MCODE algorithm in Cytoscape. A diagnostic model containing hub genes was constructed using LASSO regression and logistic regression analysis. The relationship between hub genes and drug sensitivity was explored using the DSigDB database. An interaction network between miRNA-transcription factor (TF)-hub genes was created using the Network-Analyst website.

RESULTS

A total of 1,234 MRGs, 172 DEMRGs, and 6 hub genes with good diagnostic performance were identified. Ten potential candidate drugs (rifampicin, fulvestrant, pentadecafluorooctanoic acid, etc.) were selected. Thirty-four miRNAs targeting genes in the diagnostic model (ANGPTL4, CPT2, GLUD1, MED1, and MED20), as well as 137 TFs, were identified.

CONCLUSION

Six potential candidate genes showed promising diagnostic significance. rifampicin, fulvestrant, and pentadecafluorooctanoic acid were potential drugs for future research in the treatment of schizophrenia. These findings provided valuable evidence for the understanding of schizophrenia pathogenesis, diagnosis, and drug treatment.

Regulation of ferroptosis by nanotechnology for enhanced cancer immunotherapy

INTRODUCTION

This review explores the innovative intersection of ferroptosis, a form of iron-dependent cell death, with cancer immunotherapy. Traditional cancer treatments face limitations in efficacy and specificity. Ferroptosis as a new paradigm in cancer biology, targets metabolic peculiarities of cancer cells and may potentially overcome such limitations, enhancing immunotherapy.

AREA COVERED

This review centers on the regulation of ferroptosis by nanotechnology to augment immunotherapy. It explores how nanoparticle-modulated ferroptotic cancer cells impact the TME and immune responses. The dual role of nanoparticles in modulating immune response through ferroptosis are also discussed. Additionally, it investigates how nanoparticles can be integrated with various immunotherapeutic strategies, to optimize ferroptosis induction and cancer treatment efficacy. The literature search was conducted using PubMed and Google Scholar, covering articles published up to March 2024.

EXPERT OPINION

The manuscript underscores the promising yet intricate landscape of ferroptosis in immunotherapy. It emphasizes the need for a nuanced understanding of ferroptosis' impact on immune cells and the TME to develop more effective cancer treatments, highlighting the potential of nanoparticles in enhancing the efficacy of ferroptosis and immunotherapy. It calls for deeper exploration into the molecular mechanisms and clinical potential of ferroptosis to fully harness its therapeutic benefits in immunotherapy.

Ferroptosis in ulcerative colitis: Potential mechanisms and promising therapeutic targets

Ulcerative colitis (UC) is a complex immune-mediated chronic inflammatory bowel disease. It is mainly characterized by diffuse inflammation of the colonic and rectal mucosa with barrier function impairment. Identifying new biomarkers for the development of more effective UC therapies remains a pressing task for current research. Ferroptosis is a newly identified form of regulated cell death characterized by iron-dependent lipid peroxidation. As research deepens, ferroptosis has been demonstrated to be involved in the pathological processes of numerous diseases. A growing body of evidence suggests that the pathogenesis of UC is associated with ferroptosis, and the regulation of ferroptosis provides new opportunities for UC treatment. However, the specific mechanisms by which ferroptosis participates in the development of UC remain to be more fully and thoroughly investigated. Therefore, in this review, we focus on the research advances in the mechanism of ferroptosis in recent years and describe the potential role of ferroptosis in the pathogenesis of UC. In addition, we explore the underlying role of the crosslinked pathway between ferroptosis and other mechanisms such as macrophages, neutrophils, autophagy, endoplasmic reticulum stress, and gut microbiota in UC. Finally, we also summarize the potential compounds that may act as ferroptosis inhibitors in UC in the future.

The Interplay between Ferroptosis and Neuroinflammation in Central Neurological Disorders

Central neurological disorders are significant contributors to morbidity, mortality, and long-term disability globally in modern society. These encompass neurodegenerative diseases, ischemic brain diseases, traumatic brain injury, epilepsy, depression, and more. The involved pathogenesis is notably intricate and diverse. Ferroptosis and neuroinflammation play pivotal roles in elucidating the causes of cognitive impairment stemming from these diseases. Given the concurrent occurrence of ferroptosis and neuroinflammation due to metabolic shifts such as iron and ROS, as well as their critical roles in central nervous disorders, the investigation into the co-regulatory mechanism of ferroptosis and neuroinflammation has emerged as a prominent area of research. This paper delves into the mechanisms of ferroptosis and neuroinflammation in central nervous disorders, along with their interrelationship. It specifically emphasizes the core molecules within the shared pathways governing ferroptosis and neuroinflammation, including SIRT1, Nrf2, NF-κB, Cox-2, iNOS/NO·, and how different immune cells and structures contribute to cognitive dysfunction through these mechanisms. Researchers' findings suggest that ferroptosis and neuroinflammation mutually promote each other and may represent key factors in the progression of central neurological disorders. A deeper comprehension of the common pathway between cellular ferroptosis and neuroinflammation holds promise for improving symptoms and prognosis related to central neurological disorders.

Targeting epigenetic and posttranslational modifications regulating ferroptosis for the treatment of diseases

Ferroptosis, a unique modality of cell death with mechanistic and morphological differences from other cell death modes, plays a pivotal role in regulating tumorigenesis and offers a new opportunity for modulating anticancer drug resistance. Aberrant epigenetic modifications and posttranslational modifications (PTMs) promote anticancer drug resistance, cancer progression, and metastasis. Accumulating studies indicate that epigenetic modifications can transcriptionally and translationally determine cancer cell vulnerability to ferroptosis and that ferroptosis functions as a driver in nervous system diseases (NSDs), cardiovascular diseases (CVDs), liver diseases, lung diseases, and kidney diseases. In this review, we first summarize the core molecular mechanisms of ferroptosis. Then, the roles of epigenetic processes, including histone PTMs, DNA methylation, and noncoding RNA regulation and PTMs, such as phosphorylation, ubiquitination, SUMOylation, acetylation, methylation, and ADP-ribosylation, are concisely discussed. The roles of epigenetic modifications and PTMs in ferroptosis regulation in the genesis of diseases, including cancers, NSD, CVDs, liver diseases, lung diseases, and kidney diseases, as well as the application of epigenetic and PTM modulators in the therapy of these diseases, are then discussed in detail. Elucidating the mechanisms of ferroptosis regulation mediated by epigenetic modifications and PTMs in cancer and other diseases will facilitate the development of promising combination therapeutic regimens containing epigenetic or PTM-targeting agents and ferroptosis inducers that can be used to overcome chemotherapeutic resistance in cancer and could be used to prevent other diseases. In addition, these mechanisms highlight potential therapeutic approaches to overcome chemoresistance in cancer or halt the genesis of other diseases.