Ferroptosis in mitochondrial cardiomyopathy

A caged luciferin analogue generating near-infrared bioluminescence for activity-sensing of labile iron

Iron plays a vital role in physiological processes due to its high oxygen affinity and efficient redox capability. However, perturbations in iron homeostasis, particularly in its labile forms that drive oxidative stress, have been implicated in a spectrum of pathologies, including infectious diseases, malignancies, and neurodegenerative disorders. Despite the critical importance of detecting labile Fe2+, conventional fluorescent and bioluminescent probes are constrained by inherent limitations, such as suboptimal sensitivity, elevated background noise, and inadequate tissue penetration depth. To overcome these challenges, we report the development of a novel caged luciferin analogue, O-Akalumine (O-Aka), designed with an Fe2+-specific switchable N-oxide bond to enable turn-on near-infrared (NIR) bioluminescence imaging of labile Fe2+. The bioluminescence emitted by O-Aka in the presence of native firefly luciferase is centered in the NIR spectrum (λmax = 677 nm), substantially improving signal penetration through biological tissues. Exhibiting low intrinsic background noise, high sensitivity, and deep tissue imaging capability, O-Aka effectively visualized exogenous Fe2+ in cellular models and a murine breast cancer model, as well as endogenous Fe2+ in an acute cardiac injury model. These results underscore the utility of O-Aka as a robust bioluminescent probe for elucidating the physiological and pathological roles of Fe2+ and exploring its potential anticancer mechanisms.

Hippo pathway activation mediates cardiomyocyte ferroptosis to promote dilated cardiomyopathy through downregulating NFS1

Cardiomyocyte loss by regulated death modes, like apoptosis and ferroptosis, has been implicated in the development of dilated cardiomyopathy (DCM). It remains unclear whether cardiomyocyte ferroptosis occurs as a consequence of Hippo pathway activation. Using a mouse model of DCM by overexpression of Mst1 transgene (Mst1-TG) leading to Hippo pathway activation, we showed that cardiomyocyte ferroptosis was evident by transcriptomic profiles, elevated mitochondrial Fe2+ content, increased levels of lipid peroxidation and obvious mitochondrial damage. Transcriptome revealed significant alterations of genes participating in iron metabolism and lipid peroxidation. Treatment of Mst1-TG mice with the ferroptosis inhibitor ferrostatin-1 reduced cardiomyocyte ferroptosis and improved cardiac function. Using heart samples from human patients with DCM, we also found significant cardiomyocyte loss and lipid peroxidation. In cultured cardiomyocytes, ferroptosis was induced by treatment with erastin or YAP inhibitor verteporfin, and cell ferroptosis under these conditions was largely prevented by either iron chelation or Mst1 gene knockdown. In a strain of transgenic mice with cardiomyocyte inactivation of Mst1 (dnMst1-TG), erastin-induced ferroptosis and cardiac dysfunction, seen in control mice, were mitigated. Mechanistically, nuclear YAP and YY1 were shown to interact and bind to the Nfs1 promoter, thus mediating downregulation of Nfs1 (encoding cysteine desulfurase). Subsequent inhibition of iron-sulfur cluster (ISC) biosynthesis promoted cardiomyocyte ferroptosis and DCM phenotype. Restoration of Nfs1 expression was achieved by treatment of Mst1-TG mice with AAV9-Nfs1 virus, which alleviated ferroptosis, mitochondrial damage and DCM phenotype. In conclusion, in the DCM model with Hippo pathway activation, our findings unravel that NFS1 downregulation occurs and leads to insufficient ISC biosynthesis and cardiomyocyte ferroptosis. Our findings implicate that restoration of cardiomyocyte NFS1 level may represent a new therapeutic strategy for DCM.

New developments in the role of ferroptosis in sepsis‑induced cardiomyopathy (Review)

Sepsis is a life‑threatening organ dysfunction disorder caused by dysfunctional host response to infection. Sepsis‑induced cardiomyopathy (SIC) is a common and serious complication of sepsis, and it is associated with increased mortality rates; however, its specific pathogenesis is still unclear. Ferroptosis, which is an iron‑dependent form of programmed cell death, is involved in the pathophysiology of SIC. Further study on the mechanism and therapeutic targets of ferroptosis in SIC may provide new strategies for clinical diagnosis and treatment of this condition. The present article reviews the mechanisms between SIC and ferroptosis, summarizes the progress in research of the involvement of ferroptosis in SIC and provides new potential strategies for further research and treatment in the future.

Glutaminase-1 Mediated Glutaminolysis to Glutathione Synthesis Maintains Redox Homeostasis and Modulates Ferroptosis Sensitivity in Cancer Cells

Glutaminase-1 (GLS1) has garnered considerable interest as a metabolic target in cancer due to its heightened involvement and activity. However, the precise fate of glutaminolysis catalysed by GLS1 in cancer cells remains elusive. We found that GLS1 knockout led to significant suppression of cancer cell proliferation, which can be reversed or partially restored by supplementation of glutamate or non-essential amino acids that can be converted into glutamate. The addition of spliceosomal KGA or GAC ameliorates cancer cell growth in vitro and in vivo, providing both simultaneously completely reverse the effect. The primary metabolic fate of glutamate produced through glutaminolysis in cancer cells is mainly used to produce glutathione (GSH) for redox homeostasis, not entering the tricarboxylic acid cycle or synthesising nucleotides. GSH monoethyl ester (GSH-MEE) effectively rescues the inhibition of cancer cell proliferation caused by GLS1 knockout. Deletion of GLS1 results in an elevation of reactive oxygen species (ROS) and malondialdehyde (MDA), a reduction of NADPH/NADP+ ratio, and an augmented susceptibility of cells to ferroptosis. Glutathione Peroxidase 4 (GPX4) and GPX1 exhibit complementary roles in redox regulation, with GLS1 knockout promoting GPX4 degradation. Pharmacological inhibition of GLS1 synergises with GPX4 inhibitor to suppress tumour growth. Dual targeting of GPX4 and GPX1 presents a potent anti-cancer strategy. This metabolic mechanism facilitates a deeper comprehension of the abnormal glutamine metabolism in cancer cells, establishing a theoretical basis for the potential clinical utilisation of GLS1 inhibitors and presenting novel perspectives for advancing combinatorial therapeutic approaches.

Monitoring Ferroptosis with NIR Fluorescence Probe Capable of Reversible Mitochondria Nucleus Translocation

Ferroptosis, a recently proposed form of regulated cell death, is characterized by a surge in reactive oxygen species and a subsequent depletion of glutathione. The mitochondria and nucleoli play pivotal roles in the process of ferroptosis. Therefore, monitoring the interactions between mitochondria and the nucleoli during ferroptosis is crucial for clarifying its physiological and pathological processes. In this study, we designed and synthesized the near-infrared fluorescence probe MINU, which exhibits excellent stability against biological ions and physiological pH environments. Due to its cationic structure and good DNA affinity, MINU can target both mitochondria and the nucleoli. Cell imaging demonstrates that MINU can reversibly migrate between the mitochondria and the nucleoli in response to changes in mitochondrial membrane potential. By detecting the localization and intensity of fluorescence signals, we can effectively distinguish between normal cell, apoptotic cell, and ferroptotic cell. Monitoring the interactions between mitochondria and the nucleoli allows us to more accurately appreciate the biological processes of ferroptosis.

Ferroptosis: a potential therapeutic target in cardio-cerebrovascular diseases

Cardio-cerebrovascular diseases (CCVDs) are the leading cause of global mortality, yet effective treatment options remain limited. Ferroptosis, a novel form of regulated cell death, has emerged as a critical player in various CCVDs, including atherosclerosis, myocardial infarction, ischemia-reperfusion injury, cardiomyopathy, and ischemic/hemorrhagic strokes. This review highlights the core mechanisms of ferroptosis, its pathological implications in CCVDs, and the therapeutic potential of targeting this process. Additionally, it explores the role of Chinese herbal medicines (CHMs) in mitigating ferroptosis, offering novel therapeutic strategies for CCVDs management. Ferroptosis is regulated by several key pathways. The GPX4-GSH-System Xc- axis is central to ferroptosis execution, involving GPX4 using GSH to neutralize lipid peroxides, with system Xc- being crucial for GSH synthesis. The NAD(P)H/FSP1/CoQ10 axis involves FSP1 regenerating CoQ10 via NAD(P)H, inhibiting lipid peroxidation independently of GPX4. Lipid peroxidation, driven by PUFAs and enzymes like ACSL4 and LPCAT3, and iron metabolism, regulated by proteins like TfR1 and ferritin, are also crucial for ferroptosis. Inhibiting ferroptosis shows promise in managing CCVDs. In atherosclerosis, ferroptosis inhibitors reduce iron accumulation and lipid peroxidation. In myocardial infarction, inhibitors protect cardiomyocytes by preserving GPX4 and SLC7A11 levels. In ischemia-reperfusion injury, targeting ferroptosis reduces myocardial and cerebral damage. In diabetic cardiomyopathy, Nrf2 activators alleviate oxidative stress and iron metabolism irregularities. CHMs offer natural compounds that mitigate ferroptosis. They possess antioxidant properties, chelate iron, and modulate signaling pathways like Nrf2 and AMPK. For example, Salvia miltiorrhiza and Astragalus membranaceus reduce oxidative stress, while some CHMs chelate iron, reducing its availability for ferroptosis. In conclusion, ferroptosis plays a pivotal role in CCVDs, and targeting it offers novel therapeutic avenues. CHMs show promise in reducing ferroptosis and improving patient outcomes. Future research should explore combination therapies and further elucidate the molecular interactions in ferroptosis.

Silica Nanoparticles Loaded With Selenium Quantum Dots Reduce Myocardial Ischemia-Reperfusion Injury by Alleviating Ferroptosis and Mitochondrial Dysfunction

Purpose

Myocardial ischemia-reperfusion (IR) injury, a significant challenge in cardiovascular treatment, is primarily driven by ferroptosis and mitochondrial dysfunction. Despite extensive research, no clinical therapies effectively target ferroptosis in IR injury. This study aims to develop selenium-quantum-dot-loaded porous silica nanospheres (Se@PSN) as a novel therapeutic approach to address IR injury.

Patients and Methods

Se@PSN were synthesized and tested for their reactive oxygen species (ROS) scavenging capabilities and biocompatibility. Additionally, the effects of Se@PSN on ferroptosis, mitochondrial damage, oxidative stress, and myocardial IR injury severity were evaluated.

Results

Se@PSN enhanced the stability of selenium quantum dots and exhibited strong ROS scavenging abilities. Additionally, Se@PSN exhibited excellent biocompatibility. The Se@PSN treatment increased GPX4 levels, effectively inhibiting ferroptosis in cardiomyocytes. Furthermore, Se@PSN promoted the expression of mitochondrial respiratory complexes, mitigating oxidative phosphorylation damage and preserving mitochondrial function. These effects collectively resulted in reduced myocardial loss, inflammation, and fibrosis following IR injury. Compared to PSN alone, Se@PSN showed superior therapeutic efficacy against IR injury.

Conclusion

Se@PSN exhibit great potential in reducing ferroptosis and protecting mitochondrial function, making them a promising therapeutic approach for the treatment of myocardial IR injury.

The IDH1-R132H mutation aggravates cisplatin-induced acute kidney injury by promoting ferroptosis through disrupting NDUFA1 and FSP1 interaction

The IDH1-R132H mutation is implicated in the development of various tumors. Whether cisplatin, a common chemotherapeutic agent, induces more significant renal toxicity in individuals with the IDH1-R132H mutation remains unclear. In this study, we observed that the IDH1-R132H mutation exacerbates mitochondrial lipid peroxidation and dysfunction in renal tubules, rendering the kidneys more susceptible to cisplatin-induced ferroptosis. The IDH1-R132H mutation increases methylation of the Ndufa1 promoter, thereby suppressing NDUFA1 transcription and translation. This suppression disrupts NDUFA1's interaction with FSP1, reducing its resistance to cisplatin-induced tubular epithelial cell death. As a consequence, ROS accumulates, lipid peroxidation occurs, and ferroptosis is triggered, thereby promoting acute kidney injury. In summary, this study elucidates a novel mechanism underlying cisplatin-induced nephrotoxicity and provides valuable insights for the development of personalized treatment strategies for tumor patients carrying the IDH1-R132H mutation.

Oxymatrine Inhibits Liver Cancer Progression by Regulating SIRT1/YY1/GPX4 Axis-Mediated Ferroptosis

Ferroptosis is regarded as a promising cancer therapeutic target. As a major bioactive compound from traditional Chinese medicine (TCM) herb Sophora flavescens Aiton, oxymatrine (OMT) can depress inflammatory factors, reduce iron deposition, and suppress the hub gene or protein expression involved in ferroptosis and inflammation. Additionally, OMT can control collagen deposition in the liver and has a therapeutic effect on liver cancer. This research investigated the action mechanism of the mechanism of the effect of OMT on the process of liver cancer. OMT triggered cell death and restrained cell proliferation in liver cancer cells, along with downregulated levels of Yin Yang 1 (YY1) and glutathione peroxidase 4 (GPX4) and elevated expression of silent information regulator 1 (SIRT1). Moreover, ferroptosis is the main method leading to OMT-induced liver cancer cell death. OMT-induced ferroptosis was reversed after GPX4 and YY1 overexpression or inhibition of SIRT1. Furthermore, the OMT restrained tumor growth through the SIRT1/YY1/GPX4 axis in liver cancer transplantation models. These results indicated that OMT inhibited cell viability and induced ferroptosis of liver cancer cells, involving the regulatory mechanism of the SIRT1/YY1/GPX4 axis.

ANP32E promotes esophageal cancer progression and paclitaxel resistance via P53/SLC7A11 axis-regulated ferroptosis

Esophageal cancer (EC) is associated with high mortality rates and widespread resistance to chemotherapeutic agents, like paclitaxel (PTX), posing a significant global public health challenge. ANP32E is a member of the acidic nuclear phosphoprotein 32 family, its specific biological functions and mechanisms in EC remain unclear. Through bioinformatics analysis and clinical tissue sample studies, we observed a marked upregulation of ANP32E expression in EC tissues. Utilizing ANP32E knock-out EC cell models and xenograft experiments in nude mice, we demonstrated that the absence of ANP32E significantly inhibits tumor progression and migration, whereas its overexpression exacerbates tumor growth. Transcriptomic sequencing (RNA-seq) further revealed activation of the ferroptosis pathway in ANP32E deficient cells, which was confirmed through experiments showing enhanced ferroptosis that could be reversed by the ferroptosis inhibitor ferrostatin-1. At the molecular level, ANP32E regulates EC progression and ferroptosis via the p53/SLC7A11 axis. ANP32E depletion resulted in increased p53 expression level, while inhibition of p53 partially restored the suppressed cell proliferation and increased ferroptosis in ANP32E-depleted cells. Additionally, knocking out ANP32E significantly enhanced EC cell sensitivity to PTX, Combining PTX with the ferroptosis inducer erastin was more effective in inhibiting tumor growth. In vivo, we confirmed the synergistic effect of ANP32E knock-out combined with PTX demonstrating superior tumor suppressing. Overall, our findings suggest that ANP32E regulates EC progression and ferroptosis through the p53/SLC7A11 axis, offering a potential molecular target for overcoming PTX resistance in EC treatment.

Human genetics identify convergent signals in mitochondrial LACTB-mediated lipid metabolism in cardiovascular-kidney-metabolic syndrome

The understanding of cardiovascular-kidney-metabolic syndrome remains difficult despite recently performed large scale genome-wide association studies. Here, we identified beta-lactamase (LACTB), a novel gene whose expression is targeted by genetic variations causing kidney dysfunction and hyperlipidemia. Mice with LACTB deletion developed impaired glucose tolerance, elevated lipid levels, and increased sensitivity to kidney disease, while mice with tubule-specific overexpression of LACTB were protected from kidney injury. We show that LACTB is a novel mitochondrial protease cleaving and activating phospholipase A2 group VI (PLA2G6), a kidney-metabolic risk gene itself. Genetic deletion of PLA2G6 in tubule-specific LACTB-overexpressing mice abolished the protective function of LACTB. Via mouse and human lipidomic studies, we show that LACTB and downstream PLA2G6 convert oxidized phosphatidylethanolamine to lyso-phosphatidylethanolamine and thereby regulate mitochondrial function and ferroptosis. In summary, we identify a novel gene and a core targetable pathway for kidney-metabolic disorders.

Lapatinib: A Potential Therapeutic Agent for Colon Cancer Targeting Ferroptosis

BACKGROUND

Colon cancer poses a significant threat to the lives of several patients, impacting their quality of life, thus necessitating its urgent treatment. Lapatinib, a new generation of targeted anti-tumor drugs for clinical application, has yet to be studied for its molecular mechanisms in treating colon cancer.

OBJECTIVES

This study aimed to uncover the underlying molecular mechanisms through which lapatinib exerts its therapeutic effects in colon cancer treatment.

METHODS

We accessed pertinent data on patients with colon cancer from the Cancer Genome Atlas (TCGA) database and performed bioinformatics analysis to derive valuable insights. The cell counting kit-8 (CCK8) assay was employed to assess whether lapatinib has a potential inhibitory effect on the growth and proliferation of HT- 29 cells. Additionally, we employed western blot and real-time quantitative polymerase chain reaction methods to investigate whether lapatinib regulates the expression of the ferroptosis-associated protein GPX4 in HT-29 cells. Furthermore, we utilized specific assay kits to measure the levels of reactive oxygen species (ROS) and malondialdehyde in HT-29 cells treated with lapatinib, aiming to elucidate the precise pattern of cell damage induced by this compound.

RESULTS

GPX4 exhibited high expression levels in tissues from patients with colon cancer and was significantly associated with patient prognosis and diagnosis. Lapatinib inhibited the growth and proliferation of the colon cancer cell line HT-29. Additionally, lapatinib suppressed the expression of GPX4 in HT-29 cells, while the ferroptosis inhibitor ferrostatin-1 (Fer-1) partially restored its expression. Lapatinib induced an increase in intracellular ROS levels and malondialdehyde content in HT-29 cells, with Fer-1 partially restoring these levels.

CONCLUSION

Our findings demonstrated that lapatinib could effectively suppress the mRNA and protein expression of GPX4 in colon cancer cells, which elevates intracellular levels of ROS and malondialdehyde, ultimately inducing ferroptosis in these cells. This mechanism underscores the potential of lapatinib as a therapeutic strategy for targeting tumors.

Ferroptosis and its role in osteoarthritis: mechanisms, biomarkers, and therapeutic perspectives

Osteoarthritis (OA) is one of the leading causes of disability worldwide, characterized by a complex pathological process involving cartilage degradation, synovial inflammation, and subchondral bone remodeling. In recent years, ferroptosis, a form of programmed cell death driven by iron-dependent lipid peroxidation, has been recognized as playing a critical role in the onset and progression of OA. Investigating the molecular mechanisms of ferroptosis and its involvement in OA may offer novel strategies for diagnosing and treating this disease. This review first outlines the core mechanisms of ferroptosis, with a particular focus on the roles of critical molecules such as Glutathione Peroxidase 4 (GPX4), Transferrin Receptor 1 (TfR1), and Nuclear Receptor Coactivator 4 (NCOA4). Subsequently, this study examines the specific impacts of ferroptosis on the pathophysiology of OA. Building on this, the potential of ferroptosis-related biomarkers for OA diagnosis and treatment is highlighted, along with proposed therapeutic strategies targeting ferroptosis regulation. This review aims to deepen the understanding of ferroptosis mechanisms and advance the clinical application of regulatory therapies for OA.

Evolution of Theories on Doxorubicin-Induced Late Cardiotoxicity-Role of Topoisomerase

Doxorubicin (DOX) has been widely used as a cytotoxic chemotherapeutic. However, DOX has a number of side effects, such as myelotoxicity or gonadotoxicity, the most dangerous of which is cardiotoxicity. Cardiotoxicity can manifest as cardiac arrhythmias, myocarditis, and pericarditis; life-threatening late cardiotoxicity can result in heart failure months or years after the completion of chemotherapy. The development of late cardiomyopathy is not yet fully understood. The most important question is how DOX reprograms the cardiomyocyte, after which DOX is excreted from the body, initially without symptoms. However, clinically overt cardiomyopathy develops over the following months and years. Since the 1980s, DOX-induced disorders in cardiomyocytes have been thought to be related to oxidative stress and dependent on the Fe/reactive oxygen species (ROS) mechanism. That line of evidence was supported by dexrazoxane (DEX) protection, the only Food and Drug Administration (FDA)-approved drug for preventing DOX-induced cardiomyopathy, which complexes iron. Thus, the hypothesis related to Fe/ROS provides a plausible explanation for the induction of the development of late cardiomyopathy via DOX. However, in subsequent studies, DEX was used to identify another important mechanism in DOX-induced cardiomyopathy that is related to topoisomerase 2β (Top2β). Does the Top2β hypothesis explain the mechanisms of the development of DOX-dependent late heart failure? Several of these mechanisms have been identified to date, proving the involvement of Top2β in the regulation of the redox balance, including oxidative stress. Thus, the development of late cardiomyopathy can be explained based on mechanisms related to Top2β. In this review, we highlight free radical theory, iron imbalance, calcium overload, and finally, a theory based on Top2β.

Ferroptosis in Cardiovascular Diseases and Ferroptosis-Related Intervention Approaches

OBJECTIVE

Cardiovascular diseases (CVDs) are major public health problems that threaten the lives and health of individuals. The article has reviewed recent progresses about ferroptosis and ferroptosis-related intervention approaches for the treatment of CVDs and provided more references and strategies for targeting ferroptosis to prevent and treat CVDs.

METHODS

A comprehensive review was conducted using the literature researches.

RESULTS AND DISCUSSION

Many ferroptosis-targeted compounds and ferroptosis-related genes may be prospective targets for treating CVDs and our review provides a solid foundation for further studies about the detailed pathological mechanisms of CVDs.

CONCLUSION

There are challenges and limitations about the translation of ferroptosis-targeted potential therapies from experimental research to clinical practice. It warrants further exploration to pursure safer and more effective ferroptosis-targeted thereapeutic approaches for CVDs.

Astaxanthin mediated repair of tBHP-Induced cellular injury in chondrocytes

OBJECTIVE

This study investigates how astaxanthin (AST) counters tert-butyl hydroperoxide (tBHP)-induced cellular damage in C28/I2 chondrocytes, focusing on the circ-HP1BP3/miR-139-5p/SOD1 signaling pathway and its use in sustained-release microspheres for osteoarthritis treatment.

METHODS

We employed a variety of techniques including real-time quantitative PCR, Western blot, ELISA, and dual-luciferase reporter gene assays to explore AST's molecular effects. Additionally, the efficacy of AST-loaded sustained-release microspheres was evaluated in vitro and in a mouse model of osteoarthritis.

RESULTS

AST significantly enhanced SOD1 expression, reducing apoptosis and inflammation in damaged cells. The AST-loaded microspheres showed promising in vitro drug release, improved cell viability, and reduced oxidative stress. In the osteoarthritis mouse model, they effectively decreased joint inflammation and increased the expression of chondrocyte markers.

CONCLUSION

Astaxanthin effectively mitigates oxidative stress and inflammation in chondrocytes via the circ-HP1BP3/miR-139-5p/SOD1 pathway. The development of AST-loaded microspheres offers a novel and promising approach for osteoarthritis therapy, potentially extending to osteoarthritis treatment.

Ultrasound combined with FeSO4 facilitated the occurrence of ferroptosis in Vibrio parahaemolyticus

Ultrasound (US) as a sustainable non-thermal sterilization technology that is employed either independently alone or in combination with other processing methods to eliminate food-borne pathogens in the food industry. In the present study, the synergistic effects of US combined with FeSO4 against Vibrio parahaemolyticus were investigated. The results demonstrated that the combination of ultrasound and FeSO4 had an excellent bactericidal activity on V. parahaemolyticus. Treatment with US (100 W) and FeSO4 (8 μM) for 15 min could kill more than 99.9 % cells. Furthermore, the observed cell death was identified as classical ferroptosis, characterized by ferroptosis hallmarks including iron-dependent, ROS burst, membrane damage and lipid peroxide accumulation. Addition of ferroptosis inhibitor liproxstatin-1 alleviated the cell death induced by the combination treatment. Transcriptome analysis further revealed that the US-FeSO4 treatment significantly influenced pathways related to fatty acid metabolism, ferroptosis, biofilm formation, RNA degradation, oxidative phosphorylation and other key processes, which likely contributed to the occurrence of ferroptosis. Based on these findings, we speculated that cavitation effect of US promoted the entry of Fe2+, leading to the generation of free radicals primarily responsible for ferroptosis by US-FeSO4. Taken together, this study provides valuable insights into the biological pathway involved in ultrasound sterilization and presents an alternative strategy to eradicate microorganism in food products.

A new perspective on targeting pulmonary arterial hypertension: Programmed cell death pathways (Autophagy, Pyroptosis, Ferroptosis)

Pulmonary arterial hypertension (PAH) is a severe cardiovascular disease characterized by elevated pulmonary vascular resistance, progressive increases in pulmonary artery pressures, ultimately leading to right-sided heart failure, and potentially mortality. Pulmonary vascular remodeling is pivotal in PAH onset and progression. While targeted drug therapies have notably ameliorated PAH prognosis, current medications primarily focus on vascular vasodilation, with limited ability to reverse pulmonary vascular remodeling fundamentally, resulting in suboptimal patient prognoses. Cellular death in pulmonary vasculature, once thought to be confined to apoptosis and necrosis, has evolved with the identification of pyroptosis, autophagy, and ferroptosis, revealing their association with vascular injury in PAH. These novel forms of regulated cellular death impact reactive oxygen species (ROS) generation, calcium stress, and inflammatory cascades, leading to pulmonary vascular cell loss, exacerbating vascular injury, and mediating adverse remodeling, inflammation, immune anomalies, and current emerging mechanisms (such as endothelial-mesenchymal transition, abnormal energy metabolism, and epigenetic regulation) in the pathogenesis of PAH. This review comprehensively delineates the roles of autophagy, pyroptosis, and ferroptosis in PAH, elucidating recent advances in their involvement and regulation of vascular injury. It juxtaposes their distinct functions in PAH and discusses the interplay of these programmed cell deaths in pulmonary vascular injury, highlighting the benefits of combined targeted therapies in mitigating pulmonary arterial hypertension-induced vascular injury, providing novel insights into targeted treatments for pulmonary arterial hypertension.

Cytoglobin augments ferroptosis through autophagic degradation of ferritin in colorectal cancer cells

Autophagy has gained importance in the context of ferroptosis. Nevertheless, a deeper understanding of the regulatory mechanism governing autophagy-dependent ferroptosis is necessary. Cytoglobin (CYGB), a member of the globin family, exhibits antifibrotic effects, regulates cellular reactive oxygen species, and stimulates tumor inhibition. Herein, we present further insights into the role of CYGB in ferroptosis regulation. Our investigation confirmed that CYGB impedes cell proliferation and migration. Furthermore, a significant association between CYGB and the lysosomal pathway was suggested based on the RNA sequencing data analysis. Elevated lysosomal signal and colocalization of CYGB with lysosome-associated membrane glycoprotein 1 (LAMP1) were observed. Moreover, upregulated autophagy and augmented ferroptosis induced by RSL3 were confirmed in CYGB-overexpression cells with an obviously increased colocalization of nuclear receptor coactivator 4 (NCOA4) and LC3B. The autophagy inhibitor bafilomycin or chloroquine alleviated autophagy-dependent degradation of ferritin protein under RSL3 treated condition. Additionally, a colocalization of CYGB with the transferrin receptor (TFR) was confirmed. Our results demonstrate an important functional pathway by which CYGB regulates ferroptosis through TFR-binding and autophagic degradation of ferritin, and provide a potential pathway for the treatment of colorectal cancer.

Targeting NQO1 induces ferroptosis and triggers anti-tumor immunity in immunotherapy-resistant KEAP1-deficient cancers

Immunotherapy has revolutionized cancer treatment, yet the efficacy of immunotherapeutic approaches remains limited. Resistance to ferroptosis is one of the reasons for the poor therapeutic outcomes in tumors with Kelch-like ECH-associated protein 1 (KEAP1) mutations. However, the specific mechanisms by which KEAP1-mutant tumors resist immunotherapy are not fully understood. In this study, we showed that the loss of function in KEAP1 results in resistance to ferroptosis. We identified NAD(P)H Quinone Dehydrogenase 1 (NQO1) as a transcriptional target of nuclear factor erythroid 2-related factor 2 (NRF2) and revealed that inducing NQO1-mediated ferroptosis in KEAP1-deficient tumors triggers an antitumor immune cascade. Additionally, it was found that NQO1 protein levels could serve as a candidate biomarker for predicting sensitivity to immunotherapy in clinical tumor patients. We validated these findings in several preclinical tumor models. Overall, KEAP1 mutations define a unique disease phenotype, and targeting its key downstream molecule NQO1 offers new hope for patients with resistance to immunotherapy.

Potential Roles of IP3 Receptors and Calcium in Programmed Cell Death and Implications in Cardiovascular Diseases

Inositol 1,4,5-trisphosphate receptors (IP3Rs) play a crucial role in maintaining intracellular/cytosolic calcium ion (Ca2+i) homeostasis. The release of Ca2+ from IP3Rs serves as a second messenger and a modulatory factor influencing various intracellular and interorganelle communications during both physiological and pathological processes. Accumulating evidence from in vitro, in vivo, and clinical studies supports the notion that the overactivation of IP3Rs is linked to the pathogenesis of various cardiac conditions. The overactivation of IP3Rs results in the dysregulation of Ca2+ concentration ([Ca2+]) within cytosolic, mitochondrial, and nucleoplasmic cellular compartments. In cardiovascular pathologies, two isoforms of IP3Rs, i.e., IP3R1 and IP3R2, have been identified. Notably, IP3R1 plays a pivotal role in cardiac ischemia and diabetes-induced arrhythmias, while IP3R2 is implicated in sepsis-induced cardiomyopathy and cardiac hypertrophy. Furthermore, IP3Rs have been reported to be involved in various programmed cell death (PCD) pathways, such as apoptosis, pyroptosis, and ferroptosis underscoring their multifaceted roles in cardiac pathophysiology. Based on these findings, it is evident that exploring potential therapeutic avenues becomes crucial. Both genetic ablation and pharmacological intervention using IP3R antagonists have emerged as promising strategies against IP3R-related pathologies suggesting their potential therapeutic potency. This review summarizes the roles of IP3Rs in cardiac physiology and pathology and establishes a foundational understanding with a particular focus on their involvement in the various PCD pathways within the context of cardiovascular diseases.

Borna disease virus 1 induces ferroptosis, contributing to lethal encephalitis

Borna disease virus 1 (BoDV-1) is a neurotropic RNA virus that has been linked to fatal BoDV-1 encephalitis (BVE) in humans. Ferroptosis represents a newly recognized kind of programmed cell death that marked by iron overload and lipid peroxidation. Various viral infections are closely related to ferroptosis. However, the link between BoDV-1 infection and ferroptosis, as well as its role in BVE pathogenesis, remains inadequately understood. Herein, we used primary rat cortical neurons, human microglial HMC3 cells, and Sprague‒Dawley rats as models. BoDV-1 infection induced ferroptosis, as ferroptosis characteristics were detected (iron overload, reactive oxygen species buildup, decreased antioxidant capacity, lipid peroxidation, and mitochondrial damage). Analysis via qRT-PCR and Western blot demonstrated that BoDV-1-induced ferroptosis was mediated through Nrf2/HO-1/SLC7a11/GPX4 antioxidant pathway suppression. Nrf2 downregulation was due to BoDV-1 infection promoting Nrf2 ubiquitination and degradation. Following BoDV-1-induced ferroptosis, the PTGS2/PGE2 signaling pathway was activated, and various intracellular lipid peroxidation products and damage-associated molecular patterns were released, contributing to BVE occurrence and progression. More importantly, inhibiting ferroptosis or the ubiquitin‒proteasome system effectively alleviated BVE. Collectively, these findings demonstrate the interaction between BoDV-1 infection and ferroptosis and reveal BoDV-1-induced ferroptosis as an underlying pathogenic mechanism of BVE.

Investigating the interplay between mitophagy and diabetic neuropathy: Uncovering the hidden secrets of the disease pathology

Mitophagy, the cellular process of selectively eliminating damaged mitochondria, plays a crucial role in maintaining metabolic balance and preventing insulin resistance, both key factors in type 2 diabetes mellitus (T2DM) development. When mitophagy malfunctions in diabetic neuropathy, it triggers a cascade of metabolic disruptions, including reduced energy production, increased oxidative stress, and cell death, ultimately leading to various complications. Thus, targeting mitophagy to enhance the process may have emerged as a promising therapeutic strategy for T2DM and its complications. Notably, plant-derived compounds with β-cell protective and mitophagy-stimulating properties offer potential as novel therapeutic agents. This review highlights the intricate mechanisms linking mitophagy dysfunction to T2DM and its complications, particularly neuropathy, elucidating potential therapeutic interventions for this debilitating disease.

Overactive mitochondrial DNA replication disrupts perinatal cardiac maturation

High mitochondrial DNA (mtDNA) amount has been reported to be beneficial for resistance and recovery of metabolic stress, while increased mtDNA synthesis activity can drive aging signs. The intriguing contrast of these two mtDNA boosting outcomes prompted us to jointly elevate mtDNA amount and frequency of replication in mice. We report that high activity of mtDNA synthesis inhibits perinatal metabolic maturation of the heart. The offspring of the asymptomatic parental lines are born healthy but manifest dilated cardiomyopathy and cardiac collapse during the first days of life. The pathogenesis, further enhanced by mtDNA mutagenesis, involves prenatal upregulation of mitochondrial integrated stress response and the ferroptosis-inducer MESH1, leading to cardiac fibrosis and cardiomyocyte death after birth. Our evidence indicates that the tight control of mtDNA replication is critical for early cardiac homeostasis. Importantly, ferroptosis sensitivity is a potential targetable mechanism for infantile-onset cardiomyopathy, a common manifestation of mitochondrial diseases.

Thiostrepton induces oxidative stress, mitochondrial dysfunction and ferroptosis in HaCaT cells

TST has been mainly studied for its anti-tumor proliferation and antimicrobial effects, but not widely used in dermatological diseases. The mechanism of cellular damage by TST in response to H2O2-mediated oxidative stress was investigated in human skin immortalized keratinocytes (HaCaT) as an in vitro model. The findings reveal that TST treatment leads to increased oxidative stress in the cells by reducing levels of superoxide dismutase (SOD), glutathione (GSH), and catalase (CAT). This effect is further supported by an upsurge in the expression of malondialdehyde (MDA, a pivotal marker of lipid peroxidation). Additionally, dysregulation of FoxM1 at both gene and protein levels corroborates its involvement TST associated effects. Analysis of ferroptosis-related genes confirms dysregulation following TST treatment in HaCaT cells. Furthermore, TST treatment exhibits effects on mitochondrial morphology and function, affirming its induction of apoptosis in the cells through heightened oxidative stress due to mitochondrial damage and dysregulation of mitochondrial membrane potential.

Iron metabolism in doxorubicin-induced cardiotoxicity: From mechanisms to therapies

Doxorubicin (DOX) is an anti-tumor agent for chemotherapy, but its use is often hindered by the severe and life-threatening side effect of cardiovascular toxicity. In recent years, studies have focused on dysregulated iron metabolism and ferroptosis, a unique type of cell death induced by iron overload, as key players driving the development of DOX-induced cardiotoxicity (DIC). Recent advances have demonstrated that DOX disturbs normal cellular iron metabolism, resulting in excessive iron accumulation and ferroptosis in cardiomyocytes. This review will explore how dysregulated iron homeostasis and ferroptosis drive the progression of DIC. We will also discuss the current approaches to target iron metabolism and ferroptosis to mitigate DIC. Besides, we will discuss the limitations and challenges for clinical translation for these therapeutic regimens.

Protosappanin A Protects DOX-Induced Myocardial Injury and Cardiac Dysfunction by Targeting ACSL4/FTH1 Axis-Dependent Ferroptosis

Doxorubicin (DOX) is an effective anticancer agent, but its clinical utility is constrained by dose-dependent cardiotoxicity, partly due to cardiomyocyte ferroptosis. However, the progress of developing cardioprotective medications to counteract ferroptosis has encountered obstacles. Protosappanin A (PrA), an anti-inflammatory compound derived from hematoxylin, shows potential against DOX-induced cardiomyopathy (DIC). Here, it is reported that PrA alleviates myocardial damage and dysfunction by reducing DOX-induced ferroptosis and maintaining mitochondrial homeostasis. Subsequently, the molecular target of PrA through proteome microarray, molecular docking, and dynamics simulation is identified. Mechanistically, PrA physically binds with ferroptosis-related proteins acyl-CoA synthetase long-chain family member 4 (ACSL4) and ferritin heavy chain 1 (FTH1), ultimately inhibiting ACSL4 phosphorylation and subsequent phospholipid peroxidation, while also preventing FTH1 autophagic degradation and subsequent release of ferrous ions (Fe2+) release. Given the critical role of ferroptosis in the pathogenesis of ischemia-reperfusion (IR) injury, this further investigation posits that PrA can confer a protective effect against IR-induced cardiac damage by inhibiting ferroptosis. Overall, a novel pharmacological inhibitor is unveiled that targets ferroptosis and uncover a dual-regulated mechanism for cardiomyocyte ferroptosis in DIC, highlighting additional therapeutic options for chemodrug-induced cardiotoxicity and ferroptosis-triggered disorders.

HO-1 activation contributes to cadmium-induced ferroptosis in renal tubular epithelial cells via increasing the labile iron pool and promoting mitochondrial ROS generation

Cadmium (Cd), a prevalent environmental contaminant, has attracted widespread attention due to its serious health hazards. Ferroptosis is a form of iron-dependent oxidative cell death that contributes to the development of various kidney diseases. However, the mechanisms underlying the occurrence of ferroptosis in Cd-induced renal tubular epithelial cells (TECs) have not been fully elucidated. Hereby, both in-vitro and in-vivo experiments were established to elucidate this issue. In this study, we found that Cd elicited accumulation of lipid peroxides due to intracellular ferrous ion (Fe2+) overload and glutathione depletion, contributing to ferroptosis. Inhibition of ferroptosis via chelation of Fe2+ or reduction of lipid peroxidation can significantly mitigate Cd-induced cytotoxicity. Renal transcriptome analysis revealed that the activation of heme oxygenase 1 (HO-1) was closely related to ferroptosis in Cd-induced TECs injury. Cd-induced ferroptosis and resultant TECs injury are significantly alleviated due to HO-1 inhibition, demonstrating the crucial role of HO-1 in Cd-triggered ferroptosis. Further studies showed that accumulation of lipid peroxides due to iron overload and mitochondrial ROS (mtROS) generation was responsible for HO-1-triggered ferroptosis in Cd-induced cytotoxicity. In conclusion, the current study demonstrates that excessively upregulating HO-1 promotes iron overload and mtROS overproduction to trigger ferroptosis in Cd-induced TECs injury, highlighting that targeting HO-1-mediated ferroptosis may provide new ideas for preventing Cd-induced nephrotoxicity.

ZMAT2 condensates regulate the alternative splicing of TRIM28 to reduce cellular ROS accumulation, thereby promoting the proliferation of HCC cells

Dysregulation of splicing factor expression plays a crucial role in the progression of hepatocellular carcinoma (HCC). Our research found that the expression level of splicing factor ZMAT2 was increased in HCC, promoting the proliferation of HCC cells. RNAseq data indicated that the absence of ZMAT2 induced skipping exon of mRNA, while RIPseq data further revealed the mRNA binding motifs of ZMAT2. A comprehensive analysis of RNAseq and RIPseq data indicateed that ZMAT2 played a crucial role in the maturation process of TRIM28 mRNA. Knocking down of ZMAT2 led to the deletion of 25 bases in exon 11 of TRIM28, ultimately resulting in nonsense-mediated decay (NMD). Our data revealed that ZMAT2 could regulate TRIM28 to reduce the accumulation of ROS in HCC cells, thereby promoting their proliferation. Our research also discovered that ZMAT2 was capable of undergoing phase separation, resulting in the formation of liquid droplet condensates within HCC cells. Additionally, it was found that ZMAT2 was able to form protein-nucleic acid condensates with TRIM28 mRNA. In summary, this study is the first to reveal that ZMAT2 and TRIM28 mRNA form protein-nucleic acid condensates, thereby regulating the splicing of TRIM28 mRNA. The increased expression of ZMAT2 in HCC leads to upregulated TRIM28 expression and reduced ROS accumulation, ultimately accelerating the proliferation of HCC cells.

The involvement of the Stat1/Nrf2 pathway in exacerbating Crizotinib-induced liver injury: implications for ferroptosis

Crizotinib carries an FDA hepatotoxicity warning, yet analysis of the FAERS database suggests that the severity of its hepatotoxicity risks, including progression to hepatitis and liver failure, might be underreported. However, the underlying mechanism remains poorly understood, and effective intervention strategies are lacking. Here, mRNA-sequencing analysis, along with KEGG and GO analyses, revealed that DEGs linked to Crizotinib-induced hepatotoxicity predominantly associate with the ferroptosis pathway which was identified as the principal mechanism behind Crizotinib-induced hepatocyte death. Furthermore, we found that ferroptosis inhibitors, namely Ferrostatin-1 and Deferoxamine mesylate, significantly reduced Crizotinib-induced hepatotoxicity and ferroptosis in both in vivo and in vitro settings. We have also discovered that overexpression of AAV8-mediated Nrf2 could mitigate Crizotinib-induced hepatotoxicity and ferroptosis in vivo by restoring the imbalance in glutathione metabolism, iron homeostasis, and lipid peroxidation. Additionally, both Stat1 deficiency and the Stat1 inhibitor NSC118218 were found to reduce Crizotinib-induced ferroptosis. Mechanistically, Crizotinib induces the phosphorylation of Stat1 at Ser727 but not Tyr701, promoting the transcriptional inhibition of Nrf2 expression after its entry into the nucleus to promote ferroptosis. Meanwhile, we found that MgIG and GA protected against hepatotoxicity to counteract ferroptosis without affecting or compromising the anti-cancer activity of Crizotinib, with a mechanism potentially related to the Stat1/Nrf2 pathway. Overall, our findings identify that the phosphorylation activation of Stat1 Ser727, rather than Tyr701, promotes ferroptosis through transcriptional inhibition of Nrf2, and highlight MgIG and GA as potential therapeutic approaches to enhance the safety of Crizotinib-based cancer therapy.

The Role of Endothelial Cell Mitophagy in Age-Related Cardiovascular Diseases

Aging is a major risk factor for cardiovascular diseases (CVD), and mitochondrial autophagy impairment is considered a significant physiological change associated with aging. Endothelial cells play a crucial role in maintaining vascular homeostasis and function, participating in various physiological processes such as regulating vascular tone, coagulation, angiogenesis, and inflammatory responses. As aging progresses, mitochondrial autophagy impairment in endothelial cells worsens, leading to the development of numerous cardiovascular diseases. Therefore, regulating mitochondrial autophagy in endothelial cells is vital for preventing and treating age-related cardiovascular diseases. However, there is currently a lack of systematic reviews in this area. To address this gap, we have written this review to provide new research and therapeutic strategies for managing aging and age-related cardiovascular diseases.

Glutathione determines chronic myeloid leukemia vulnerability to an inhibitor of CMPK and TMPK

Bcr-Abl transformation leads to chronic myeloid leukemia (CML). The acquirement of T315I mutation causes tyrosine kinase inhibitors (TKI) resistance. This study develops a compound, JMF4073, inhibiting thymidylate (TMP) and cytidylate (CMP) kinases, aiming for a new therapy against TKI-resistant CML. In vitro and in vivo treatment of JMF4073 eliminates WT-Bcr-Abl-32D CML cells. However, T315I-Bcr-Abl-32D cells are less vulnerable to JMF4073. Evidence is presented that ATF4-mediated upregulation of GSH causes T315I-Bcr-Abl-32D cells to be less sensitive to JMF4073. Reducing GSH biosynthesis generates replication stress in T315I-Bcr-Abl-32D cells that require dTTP/dCTP synthesis for survival, thus enabling JMF4073 susceptibility. It further shows that the levels of ATF4 and GSH in several human CML blast-crisis cell lines are inversely correlated with JMF4073 sensitivity, and the combinatory treatment of JMF4073 with GSH reducing agent leads to synthetic lethality in these CML blast-crisis lines. Altogether, the investigation indicates an alternative option in CML therapy.

A longitudinal evaluation of oxidative stress - mitochondrial dysfunction - ferroptosis genes in anthracycline-induced cardiotoxicity

BACKGROUND

Antineoplastic medications, including doxorubicin, idarubicin, and epirubicin, have been found to adversely affect the heart due to oxidative stress - mitochondrial dysfunction - ferroptosis (ORMFs), which act as contributing attributes to anthracycline-induced cardiotoxicity. To better understand this phenomenon, the time-resolved measurements of ORMFS genes were analyzed in this study.

METHODS

The effect of three anthracycline drugs on ORMFs genes was studied using a human 3D cardiac microtissue cell model. Transcriptome data was collected over 14 days at two doses (therapeutic and toxic). WGCNA identified key module-related genes, and functional enrichment analysis investigated the biological processes quantified by ssGSEA, such as immune cell infiltration and angiogenesis. Biopsies were collected from heart failure patients and control subjects. GSE59672 and GSE2965 were collected for validation. Molecular docking was used to identify anthracyclines's interaction with key genes.

RESULTS

The ORMFs genes were screened in vivo or in vitro. Using WGCNA, six co-expressed gene modules were grouped, with MEblue emerging as the most significant module. Eight key genes intersecting the blue module with the dynamic response genes were obtained: CD36, CDH5, CHI3L1, HBA2, HSD11B1, OGN, RPL8, and VWF. Compared with control samples, all key genes except RPL8 were down-regulated in vitro ANT treatment settings, and their expression levels varied over time. According to functional analyses, the key module-related genes were engaged in angiogenesis and the immune system pathways. In all ANT-treated settings, ssGSEA demonstrated a significant down-regulation of angiogenesis score and immune cell activity, including Activated CD4 T cell, Immature B cell, Memory B cell, Natural killer cell, Type 1 T helper cell, and Type 2 T helper cell. Molecular docking revealed that RPL8 and CHI3L1 show significant binding affinity for anthracyclines.

CONCLUSION

This study focuses on the dynamic characteristics of ORMFs genes in both human cardiac microtissues and cardiac biopsies from ANT-treated patients. It has been highlighted that ORMFs genes may contribute to immune infiltration and angiogenesis in cases of anthracycline-induced cardiotoxicity. A thorough understanding of these genes could potentially lead to improved diagnosis and treatment of the disease.

Targeting ferroptosis: a new therapeutic opportunity for kidney diseases

Ferroptosis is a form of non-apoptotic regulated cell death (RCD) that depends on iron and is characterized by the accumulation of lipid peroxides to lethal levels. Ferroptosis involves multiple pathways including redox balance, iron regulation, mitochondrial function, and amino acid, lipid, and glycometabolism. Furthermore, various disease-related signaling pathways also play a role in regulating the process of iron oxidation. In recent years, with the emergence of the concept of ferroptosis and the in-depth study of its mechanisms, ferroptosis is closely associated with various biological conditions related to kidney diseases, including kidney organ development, aging, immunity, and cancer. This article reviews the development of the concept of ferroptosis, the mechanisms of ferroptosis (including GSH-GPX4, FSP1-CoQ1, DHODH-CoQ10, GCH1-BH4, and MBOAT1/2 pathways), and the latest research progress on its involvement in kidney diseases. It summarizes research on ferroptosis in kidney diseases within the frameworks of metabolism, reactive oxygen biology, and iron biology. The article introduces key regulatory factors and mechanisms of ferroptosis in kidney diseases, as well as important concepts and major open questions in ferroptosis and related natural compounds. It is hoped that in future research, further breakthroughs can be made in understanding the regulation mechanism of ferroptosis and utilizing ferroptosis to promote treatments for kidney diseases, such as acute kidney injury(AKI), chronic kidney disease (CKD), diabetic nephropathy(DN), and renal cell carcinoma. This paves the way for a new approach to research, prevent, and treat clinical kidney diseases.

Bone marrow mesenchymal stem cells-derived exosomal lncRNA GAS5 mitigates heart failure by inhibiting UL3/Hippo pathway-mediated ferroptosis

BACKGROUND

Exosomes (Exos) are involved in the therapeutic effects of bone marrow mesenchymal stem cells (BMSCs) on heart failure (HF). We investigated the molecular mechanisms underlying the involvement of BMSC-Exos in ferroptosis on HF.

METHODS

A rat model of HF and cellular model of hypoxia were established. BMSC-Exos were injected into model rats or co-cultured with model cells. In model rats, the cardiac function (echocardiography), oxidative stress (commercial kits), pathological damage (HE staining), fibrosis (MASSON staining), iron deposition (Prussian blue staining), and cell apoptosis (TUNEL staining) were examined. Viability (cell counting kit-8; CCK-8), cell cycle (flow cytometry), oxidative stress, and Fe2+ levels were detected in the model cells. GAS5, UL3, YAP, and TAZ expression were detected using qRT-PCR, western blotting, and immunohistochemistry analyses.

RESULTS

BMSC-Exos restored cardiac function and inhibited oxidative stress, apoptosis, pathological damage, fibrosis, and iron deposition in myocardial tissues of HF rats. In hypoxic cells, BMSC-Exos increased cell viability, decreased the number of G1 phase cells, decreased Fe2+ levels, and inhibited oxidative stress. Ferrostatin-1 (a ferroptosis inhibitor) exhibited a synergistic effect with BMSC-Exos. Additionally, GAS5 was upregulated in BMSC-Exos, further upregulating its target UL3 and Hippo pathway effectors (YAP and TAZ). The relieving effects of BMSC-Exos on HF or hypoxia-induced injury were enhanced by GAS5 overexpression, but weakened by UL3 silencing or verteporfin (a YAP inhibitor).

CONCLUSIONS

GAS5-harbouring BMSC-Exos inhibited ferroptosis by regulating the UL3/Hippo pathway, contributing to HF remission in vivo and in vitro.

Metaplastic regeneration in the mouse stomach requires a reactive oxygen species pathway

In pyloric metaplasia, mature gastric chief cells reprogram via an evolutionarily conserved process termed paligenosis to re-enter the cell cycle and become spasmolytic polypeptide-expressing metaplasia (SPEM) cells. Here, we use single-cell RNA sequencing (scRNA-seq) following injury to the murine stomach to analyze mechanisms governing paligenosis at high resolution. Injury causes induced reactive oxygen species (ROS) with coordinated changes in mitochondrial activity and cellular metabolism, requiring the transcriptional mitochondrial regulator Ppargc1a (Pgc1α) and ROS regulator Nf2el2 (Nrf2). Loss of the ROS and mitochondrial control in Ppargc1a-/- mice causes the death of paligenotic cells through ferroptosis. Blocking the cystine transporter SLC7A11(xCT), which is critical in lipid radical detoxification through glutathione peroxidase 4 (GPX4), also increases ferroptosis. Finally, we show that PGC1α-mediated ROS and mitochondrial changes also underlie the paligenosis of pancreatic acinar cells. Altogether, the results detail how metabolic and mitochondrial changes are necessary for injury response, regeneration, and metaplasia in the stomach.

Sensing of mitochondrial DNA by ZBP1 promotes RIPK3-mediated necroptosis and ferroptosis in response to diquat poisoning

Diquat (DQ) poisoning is a severe medical condition associated with life-threatening implications and multiorgan dysfunction. Despite its clinical significance, the precise underlying mechanism remains inadequately understood. This study elucidates that DQ induces instability in the mitochondrial genome of endothelial cells, resulting in the accumulation of Z-form DNA. This process activates Z-DNA binding protein 1 (ZBP1), which then interacts with receptor-interacting protein kinase 3 (RIPK3), ultimately leading to RIPK3-dependent necroptotic and ferroptotic signaling cascades. Specific deletion of either Zbp1 or Ripk3 in endothelial cells simultaneously inhibits both necroptosis and ferroptosis. This dual inhibition significantly reduces organ damage and lowers mortality rate. Notably, our investigation reveals that RIPK3 has a dual role. It not only phosphorylates MLKL to induce necroptosis but also phosphorylates FSP1 to inhibit its enzymatic activity, promoting ferroptosis. The study further shows that deletion of mixed lineage kinase domain-like (Mlkl) and the augmentation of ferroptosis suppressor protein 1 (FSP1)-dependent non-canonical vitamin K cycling can provide partial protection against DQ-induced organ damage. Combining Mlkl deletion with vitamin K treatment demonstrates a heightened efficacy in ameliorating multiorgan damage and lethality induced by DQ. Taken together, this study identifies ZBP1 as a crucial sensor for DQ-induced mitochondrial Z-form DNA, initiating RIPK3-dependent necroptosis and ferroptosis. These findings suggest that targeting the ZBP1/RIPK3-dependent necroptotic and ferroptotic pathways could be a promising approach for drug interventions aimed at mitigating the adverse consequences of DQ poisoning.

Miro-mediated mitochondrial transport: A new dimension for disease-related abnormal cell metabolism?

Mitochondria are versatile and highly dynamic organelles found in eukaryotic cells that play important roles in a variety of cellular processes. The importance of mitochondrial transport in cell metabolism, including variations in mitochondrial distribution within cells and intercellular transfer, has grown in recent years. Several studies have demonstrated that abnormal mitochondrial transport represents an early pathogenic alteration in a variety of illnesses, emphasizing its significance in disease development and progression. Mitochondrial Rho GTPase (Miro) is a protein found on the outer mitochondrial membrane that is required for cytoskeleton-dependent mitochondrial transport, mitochondrial dynamics (fusion and fission), and mitochondrial Ca2+ homeostasis. Miro, as a critical regulator of mitochondrial transport, has yet to be thoroughly investigated in illness. This review focuses on recent developments in recognizing Miro as a crucial molecule in controlling mitochondrial transport and investigates its roles in diverse illnesses. It also intends to shed light on the possibilities of targeting Miro as a therapeutic method for a variety of diseases.

Nicorandil alleviates cardiac microvascular ferroptosis in diabetic cardiomyopathy: Role of the mitochondria-localized AMPK-Parkin-ACSL4 signaling pathway

Mitochondria-associated ferroptosis exacerbates cardiac microvascular dysfunction in diabetic cardiomyopathy (DCM). Nicorandil, an ATP-sensitive K+ channel opener, protects against endothelial dysfunction, mitochondrial dysfunction, and DCM; however, its effects on ferroptosis and mitophagy remain unexplored. The present study aimed to assess the beneficial effects of nicorandil against endothelial ferroptosis in DCM and the underlying mechanisms. Cardiac microvascular perfusion was assessed using a lectin perfusion assay, while mitophagy was assessed via mt-Keima transfection and transmission electron microscopy. Ferroptosis was examined using mRNA sequencing, fluorescence staining, and western blotting. The mitochondrial localization of Parkin, ACSL4, and AMPK was determined via immunofluorescence staining. Following long-term diabetes, nicorandil treatment improved cardiac function and remodeling by alleviating cardiac microvascular injuries, as evidenced by the improved microvascular perfusion and structural integrity. mRNA-sequencing and biochemical analyses showed that ferroptosis occurred and Pink1/Parkin-dependent mitophagy was suppressed in cardiac microvascular endothelial cells after diabetes. Nicorandil treatment suppressed mitochondria-associated ferroptosis by promoting the Pink1/Parkin-dependent mitophagy. Moreover, nicorandil treatment increased the phosphorylation level of AMPKα1 and promoted its mitochondrial translocation, which further inhibited the mitochondrial translocation of ACSL4 via mitophagy and ultimately suppressed mitochondria-associated ferroptosis. Importantly, overexpression of mitochondria-localized AMPKα1 (mitoAα1) shared similar benefits with nicorandil on mitophagy, ferroptosis and cardiovascular protection against diabetic injury. In conclusion, the present study demonstrated the therapeutic effects of nicorandil against cardiac microvascular ferroptosis in DCM and revealed that the mitochondria-localized AMPK-Parkin-ACSL4 signaling pathway mediates mitochondria-associated ferroptosis and the development of cardiac microvascular dysfunction.

Deciphering the link: ferroptosis and its role in glioma

Glioma, as the most frequently occurring primary malignancy in the central nervous system, significantly impacts patients' quality of life and cognitive abilities. Ferroptosis, a newly discovered form of cell death, is characterized by significant iron accumulation and lipid peroxidation. This process is fundamentally dependent on iron. Various factors inducing ferroptosis can either directly or indirectly influence glutathione peroxidase, leading to reduced antioxidant capabilities and an increase in lipid reactive oxygen species (ROS) within cells, culminating in oxidative cell death. Recent research indicates a strong connection between ferroptosis and a range of pathophysiological conditions, including tumors, neurological disorders, ischemia-reperfusion injuries, kidney damage, and hematological diseases. The regulation of ferroptosis to intervene in the progression of these diseases has emerged as a major area of interest in etiological research and therapy. However, the exact functional alterations and molecular mechanisms underlying ferroptosis remain to be extensively studied. The review firstly explores the intricate relationship between ferroptosis and glioma, highlighting how ferroptosis contributes to glioma pathogenesis and how glioma cells may resist this form of cell death. Then, we discuss recent studies that have identified potential ferroptosis inducers and inhibitors, which could serve as novel therapeutic strategies for glioma. We also examine the current challenges in targeting ferroptosis in glioma treatment, including the complexity of its regulation and the need for precise delivery methods. This review aims to provide a comprehensive overview of the current state of research on ferroptosis in glioma, offering insights into future therapeutic strategies and the broader implications of this novel cell death pathway in cancer biology.

Temporal dynamics of muscle mitochondrial uncoupling-induced integrated stress response and ferroptosis defense

Mitochondria play multifaceted roles in cellular function, and impairments across domains of mitochondrial biology are known to promote cellular integrated stress response (ISR) pathways as well as systemic metabolic adaptations. However, the temporal dynamics of specific mitochondrial ISR related to physiological variations in tissue-specific energy demands remains unknown. Here, we conducted a comprehensive 24-hour muscle and plasma profiling of male and female mice with ectopic mitochondrial respiratory uncoupling in skeletal muscle (mUcp1-transgenic, TG). TG mice are characterized by increased muscle ISR, elevated oxidative stress defense, and increased secretion of FGF21 and GDF15 as ISR-induced myokines. We observed a temporal signature of both cell-autonomous and systemic ISR in the context of endocrine myokine signaling and cellular redox balance, but not of ferroptotic signature which was also increased in TG muscle. We show a progressive increase of muscle ISR on transcriptional level during the active phase (night time), with a subsequent peak in circulating FGF21 and GDF15 in the early resting phase. Moreover, we found highest levels of muscle oxidative defense (GPX and NQO1 activity) between the late active to early resting phase, which could aim to counteract excessive iron-dependent lipid peroxidation and ferroptosis in muscle of TG mice. These findings highlight the temporal dynamics of cell-autonomous and endocrine ISR signaling under skeletal muscle mitochondrial uncoupling, emphasizing the importance of considering such dissociation in translational strategies and sample collection for diagnostic biomarker analysis.