Thrombin induces ACSL4-dependent ferroptosis during cerebral ischemia/reperfusion

Ferroptosis and hearing loss: from molecular mechanisms to therapeutic interventions

Hearing loss profoundly affects social engagement, mental health, cognition, and brain development, with sensorineural hearing loss (SNHL) being a major concern. Linked to ototoxic medications, ageing, and noise exposure, SNHL presents significant treatment challenges, highlighting the need for effective prevention and regeneration strategies. Ferroptosis, a distinct form of cell death featuring iron-dependent lipid peroxidation, has garnered interest due to its potential role in cancer, ageing, and neuronal degeneration, especially hearing loss. The emerging role of ferroptosis as a crucial mediator in SNHL suggests that it may offer a novel therapeutic target for otoprotection. This review aims to summarise the intricate connection between ferroptosis and SNHL, offering a fresh perspective for exploring targeted therapeutic strategies that could potentially mitigate cochlear cells damage and enhance the quality of life for individuals with hearing impairments.

Netrin-1 binding to UNC5b improves post-stroke neuronal ferroptosis via AMPK-BACH1 pathway

Ferroptosis contributes to neuronal destruction after ischemic stroke which may be improved by inhibiting BTB domain and CNC homolog 1 (BACH1), a recently recognized ferroptosis facilitator. Axon guidance molecule netrin-1 (Ntn1) functions in neuroprotection against ischemic insult by engaging into its receptor of uncoordinated-5 homolog B (UNC5b) via adenosine 5'-monophosphate-activated protein kinase (AMPK), which potentially binds to BACH1. Whether Ntn1/UNC5b regulates post-stroke ferroptosis through AMPK-BACH1 pathway remains unclear. Ntn1 supplementation and UNC5b knockdown by siRNA were performed in photo-thrombosis stroke mice and oxygen-glucose deprivation-treated HT22 neurons. AMPK inhibitor BAY3827 and BACH1 activator Leptomycin B (LMB) were administrated. Ferroptosis was determined by ferroptosis-associated proteins (FSP1, GPX4 and ACSL4), Fe2+, malondialdehyde and mitochondrial morphology. BACH1 and p-AMPK/AMPK as well as the interaction between them were examined by Western blot and co-immunoprecipitation. Neuronal ferroptosis and the protein levels of BACH1 and p-AMPK were increased after photo-thrombosis and oxygen-glucose deprivation. Ntn1 supplementation or UNC5b knockdown relieved neuronal ferroptosis and neurological impairment with downregulated BACH1 and upregulated p-AMPK, nonetheless, UNC5b knockdown prevented the beneficial role of Ntn1. Both BAY3827 and LMB could reverse the change of ferroptosis caused by Ntn1 where BAY3827 inhibited the effects of Ntn1 to p-AMPK and BACH1 while LMB only inhibited the effect of Ntn1 to BACH1 without p-AMPK, suggesting BACH1 was regulated by AMPK. Co-immunoprecipitation verified that AMPK could physically bind to BACH1. Our results demonstrate UNC5b-evoked neuronal ferroptosis post stroke, and favor that Ntn1 improves post-stroke ferroptosis by its interaction with UNC5b via the AMPK-BACH1 pathway.

Inhibition of the cGAS-STING pathway: contributing to the treatment of cerebral ischemia-reperfusion injury

The cGAS-STING pathway plays an important role in ischemia-reperfusion injury in the heart, liver, brain, and kidney, but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed. Here, we outline the components of the cGAS-STING pathway and then analyze its role in autophagy, ferroptosis, cellular pyroptosis, disequilibrium of calcium homeostasis, inflammatory responses, disruption of the blood-brain barrier, microglia transformation, and complement system activation following cerebral ischemia-reperfusion injury. We further analyze the value of cGAS-STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms. Inhibition of the cGAS-STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.

Molecular mechanisms of programmed cell death and potential targeted pharmacotherapy in ischemic stroke (Review)

Stroke poses a threat to the elderly, being the second leading cause of death and the third leading cause of disability worldwide. Ischemic stroke (IS), resulting from arterial occlusion, accounts for ~85% of all strokes. The pathophysiological processes involved in IS are intricate and complex. Currently, tissue plasminogen activator (tPA) is the only Food and Drug Administration‑approved drug for the treatment of IS. However, due to its limited administration window and the risk of symptomatic hemorrhage, tPA is applicable to only ~10% of patients with stroke. Additionally, the reperfusion process associated with thrombolytic therapy can further exacerbate damage to brain tissue. Therefore, a thorough understanding of the molecular mechanisms underlying IS‑induced injury and the identification of potential protective agents is critical for effective IS treatment. Over the past few decades, advances have been made in exploring potential protective drugs for IS. The present review summarizes the specific mechanisms of various forms of programmed cell death (PCD) induced by IS and highlights potential protective drugs targeting different PCD pathways investigated over the last decade. The present review provides a theoretical foundation for basic research and insights for the development of pharmacotherapy for IS.

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.

Hydroxycitric acid inhibits ferroptosis and ameliorates benign prostatic hyperplasia by upregulating the Nrf2/GPX4 pathway

PURPOSE

Benign prostatic hyperplasia (BPH) poses a significant public health challenge, affecting a substantial portion of aging men worldwide. Current therapeutic options offer limited efficacy. The pathogenesis of BPH is multifactorial, involving ferroptosis, oxidative stress, and chronic inflammation. Hydroxycitric acid (HCA) is a natural compound with diverse pharmacological activities, including the inhibition of ferroptosis, anti-inflammatory, anti-oxidative stress, and anti-tumor effects. However, its role in BPH remains unexplored. This study aimed to investigate the effects of HCA on BPH and elucidate the underlying mechanisms, with the goal of providing novel therapeutic insights for BPH treatment.

METHODS

C57BL/6J mice were used to establish a BPH model induced by testosterone propionate (TP). Animals were then randomly assigned to the following groups: Sham, BPH, BPH + Lip-1, BPH + Bru, BPH + HCA + Bru, and BPH + HCA. Prostate index (PI) was determined, and histopathological changes were evaluated by hematoxylin and eosin (HE) staining. Mitochondrial morphology was analyzed by TEM. The levels of Fe2+, MDA, and GSH in prostate tissues were measured. Western blot analysis was performed to assess the protein expression of Nrf2 and GPX4.

RESULTS

Compared to the Sham group, the prostate tissues of the BPH group exhibited typical histopathological features of hyperplasia, including epithelial cell proliferation, increased glandular lumen size. Concurrently, the levels of ferroptosis markers Fe2+ (P < 0.01) and MDA (P < 0.001) were significantly elevated, while the expression of GSH (P < 0.01) and GPX4 (P < 0.05) was downregulated. Furthermore, mitochondrial morphology showed abnormalities. HCA treatment significantly reduced PI (P < 0.01) and attenuated epithelial cell proliferation and glandular lumen enlargement (P < 0.01, P < 0.001, respectively). HCA also reduced the levels of Fe2+ (P < 0.05) and MDA (P < 0.05), and elevated GSH levels (P < 0.01). Furthermore, HCA upregulated the expression of Nrf2 (P < 0.01) and GPX4 (P < 0.01). The Nrf2 inhibitor Brusatol increased the levels of Fe2+ (P < 0.05) and MDA (P < 0.05), and downregulated the expression of Nrf2 (P < 0.05) and GPX4 (P < 0.05), thereby attenuating the protective effects of HCA. However, co-administration of HCA and Brusatol partially reversed changes in Fe2+ (P < 0.05) and MDA (P < 0.05) levels, and increased the expression of Nrf2 (P < 0.05) and GPX4 (P < 0.05), indicating reduction in Brusatol-induced effects. Furthermore, HCA treatment did not significantly affect liver and kidney function markers (AST, ALT, SCR, and UR) (P > 0.05).

CONCLUSION

HCA inhibits ferroptosis by activating the Nrf2/GPX4 pathway, thereby ameliorating the pathological changes in BPH induced by TP. This study suggests a novel therapeutic strategy for BPH.

Neuroferroptosis in health and diseases

Ferroptosis is a type of cell death process defined by iron-dependent peroxidation of phospholipids leading to the destruction of cellular membranes and death of the cell. Ferroptosis occurs throughout the body, but a considerable research focus on ferroptosis in the brain - neuroferroptosis - has been driven by the rich lipid and iron content of the brain as well as its high oxygen consumption. Neurons also have an exceptionally large surface area and metabolic demand, which necessitates specific mechanisms (such as lipid antioxidants) to engage constantly to protect the plasma membrane against lipid peroxidation. Ferroptosis has been extensively linked to neurodegeneration and ischaemia and is increasingly implicated in physiological processes such as neuronal reprogramming. Astrocytes provide metabolic support to neurons, enabling them to defend against ferroptosis, yet ferroptotic signals in microglia can propagate damage to astrocytes and neurons, highlighting the complex intercellular (patho)physiology of neuroferroptosis.

LncRNA MEG3 promotes pyroptosis via miR-145-5p/TLR4/NLRP3 axis and aggravates cerebral ischemia-reperfusion injury

Long noncoding RNA (lncRNA) MEG3 has been considered as a novel target for alleviating the brain tissue damage during cerebral ischemia-reperfusion injury (CIRI). Numerous studies have reported that pyroptosis is involved in the pathogenesis of CIRI. This study focused on whether MEG3 modulates CIRI via pyroptosis and its underlying mechanism. The middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model and the oxygen glucose deprivation/reoxygenation (OGD/R) cell model were established. si-MEG3 and miR-145-5p inhibitor were transfected to inhibit MEG3 and miR-145-5p, respectively. As a TLR4 inhibitor, Resatorvid inhibits the TLR4 signaling pathway. TTC and TUNEL staining were used for infarction volume and cell death detection. The differential expression of MGE3, miR-145-5p, TLR4, NLRP3, Caspase-1, IL-1β, and IL-18 was determined using real-time PCR and western blot. The interaction between MEG3 and miR-145-5p, as well as between miR-145-5p and TLR4 was confirmed by the dual-luciferase reporter assay. This study confirmed that the elevated expression of MEG3 during CIRI, and it contributes to pyroptosis by regulating miR-145-5p/TLR4 axis. The knockdown of MEG3 reduced the expression of TLR4, NLRP3, Caspase-1, IL-1β, and IL-18, thereby preventing pyroptosis. Inhibition of miR-145-5p reversed the effect of MEG3 knockdown and promoted pyroptosis. Resatorvid, the inhibitor of TLR4, counteracted the effect of miR-145-5p inhibitor and suppressed pyroptosis. Our findings reveal that MEG3 promotes pyroptosis via miR-145-5p/TLR4/NLRP3 axis and aggravates CIRI, suggesting a potential therapeutic target for ischemic stroke.

Chaihu-Shugan-San alleviates post-stroke depression in mice: Mechanistic insights into exosome-mediated neuroprotection

ETHNOPHARMACOLOGICAL RELEVANCE

Post-stroke depression (PSD) is common among stroke survivors and negatively impacts recovery. Chaihu-Shugan-San (CSS), a traditional Chinese medicine, has shown therapeutic potential for mood disorders, particularly PSD. Recent studies suggest that CSS's effects may be mediated by exosomes, but the mechanisms remain unclear.

AIM OF STUDY

This study aimed to evaluate the therapeutic effects of CSS on PSD in mice and investigate the underlying mechanisms, particularly the role of exosomes.

MATERIALS AND METHODS

Active compounds in CSS were identified from rat serum using liquid chromatography-mass spectrometry (LC-MS) and analyzed through network pharmacology. In vitro, an oxygen-glucose deprivation/reperfusion (OGD/R) BV2 microglia model was used to assess the effects of CSS-containing serum (CSS-S). Exosomes from OGD/R-treated BV2 microglia were isolated, labeled with PKH26, and analyzed using transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). In vivo, a photothrombotic stroke (PT) model combined with chronic unpredictable mild stress (CUMS) was used to induce PSD in mice. Behavioral assessments and histological analysis were performed, along with immunofluorescence (IF), ELISA and q-PCR to measure key protein and miR-146 expression in the hippocampus.

RESULTS

CSS treatment significantly alleviated depressive-like behaviors in the PSD mouse model. Mice treated with high-dose CSS (4.2 g/kg) exhibited increased sucrose preference, reduced immobility in the tail suspension test (TST) and forced swimming test (FST), and enhanced exploratory activity in the open field test (OFT). Histological analysis demonstrated that CSS treatment improved brain tissue integrity, alleviating neuronal damage and reducing neuroinflammation. Exosome analysis revealed that CSS increased the expression of microglia-derived exosomes in the hippocampus, which were shown to carry miR-146. Further examination of miR-146 isoforms in the hippocampal tissue revealed significant changes: miR-146b-3p and miR-146a-5p were upregulated, while miR-146a-3p and miR-146b-5p were downregulated in PSD mice. Treatment with CSS reversed the altered miRNA expression, indicating a potential mechanism for its neuroprotective effects. Additionally, CSS treatment reduced the expression of inflammatory cytokines such as S100A8, IL1β, IL6, and TNF-α, while restoring the levels of angiogenic factors VEGFC and VEGFR3. ELISA measurements showed significant decreases in cyclic AMP response element-binding protein (CREB), brain-derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT), dopamine (DA), and noradrenaline (NE) in PSD mice; high-dose CSS notably elevated CREB and BDNF levels and showed comparable effects to fluoxetine in restoring 5-HT and DA levels. Additionally, the calcium signaling pathway was implicated, with altered mRNA expressions of CaMKIIα, CREB, phosphorylated CREB (p-CREB), PDE4D, and BDNF, although fluoxetine demonstrated stronger modulatory effects than CSS.

CONCLUSIONS

CSS alleviates PSD in mice by modulating exosome-mediated signaling, particularly through the regulation of miR-146. The treatment reversed abnormal miRNA expression, reduced neuroinflammation, and improved synaptic function. These findings highlight CSS's potential as an effective therapeutic strategy for PSD by targeting exosome-mediated neuroprotection and miR-146 regulation.

PAR1 inhibition sensitizes HPV-negative HNSCC cells to ferroptosis through inhibition of the STAT3-mediated regulation of iron and lipid metabolic pathways

Ferroptosis, a cell death mechanism characterized by the accumulation of lipid peroxides and subsequent membrane disruption, is emerging as a promising strategy for cancer treatment. However, many tumors, including head and neck squamous cell carcinoma (HNSCC), show resistance to ferroptosis, which reduces its therapeutic effect. Protease-activated receptors (PARs) are highly expressed in many tumors and are closely associated with tumor progression. Our study showed that the expression of protease-activated receptor 1 (PAR1) was downregulated during ferroptosis in HPV-negative HNSCC. Further studies showed that downregulation of PAR1 expression could enhance the therapeutic effect of Erastin on HPV-negative HNSCC, where PAR1 regulated the expression levels of SLC7A11, GPX4, and FTH1. In addition, we found that PAR1 activated the JAK2/STAT3 pathway in a Rac-1-dependent manner and identified STAT3 as a critical transcription factor in PAR1-mediated HPV-negative HNSCC progression and ferroptosis regulation. Inhibition of STAT3 expression attenuated the tumorigenicity of PAR1. It is worth noting that the PAR1 small molecule inhibitor Vorapaxar can further enhance the therapeutic effect of Erastin on HPV-negative HNSCC. Therefore, we propose that PAR1 participates in the progression of HPV-negative HNSCC through STAT3 and reduces the sensitivity of HPV-negative HNSCC to ferroptosis, providing a new perspective for discovering ferroptosis regulatory factors.

Protein kinases in neurodegenerative diseases: current understandings and implications for drug discovery

Neurodegenerative diseases (e.g., Alzheimer's, Parkinson's, Huntington's disease, and Amyotrophic Lateral Sclerosis) are major health threats for the aging population and their prevalences continue to rise with the increasing of life expectancy. Although progress has been made, there is still a lack of effective cures to date, and an in-depth understanding of the molecular and cellular mechanisms of these neurodegenerative diseases is imperative for drug development. Protein phosphorylation, regulated by protein kinases and protein phosphatases, participates in most cellular events, whereas aberrant phosphorylation manifests as a main cause of diseases. As evidenced by pharmacological and pathological studies, protein kinases are proven to be promising therapeutic targets for various diseases, such as cancers, central nervous system disorders, and cardiovascular diseases. The mechanisms of protein phosphatases in pathophysiology have been extensively reviewed, but a systematic summary of the role of protein kinases in the nervous system is lacking. Here, we focus on the involvement of protein kinases in neurodegenerative diseases, by summarizing the current knowledge on the major kinases and related regulatory signal transduction pathways implicated in diseases. We further discuss the role and complexity of kinase-kinase networks in the pathogenesis of neurodegenerative diseases, illustrate the advances of clinical applications of protein kinase inhibitors or novel kinase-targeted therapeutic strategies (such as antisense oligonucleotides and gene therapy) for effective prevention and early intervention.

Auricular Transcutaneous Vagus Nerve Stimulation Enhances Post-Stroke Neurological and Cognitive Recovery in Mice by Suppressing Ferroptosis Through α7 Nicotinic Acetylcholine Receptor Activation

AIMS

Ferroptosis plays a critical role in stroke pathophysiology, yet its dynamics during recovery remain unclear. This study aimed to investigate the evolution of ferroptosis throughout post-stroke recovery and evaluate auricular transcutaneous vagus nerve stimulation (atVNS) as a therapeutic intervention, focusing on the involvement of α7 nicotinic acetylcholine receptor (α7nAChR)-mediated mechanisms.

METHODS

Using a middle cerebral artery occlusion (MCAO) mouse model, we examined ferroptosis-related protein expression (GPX4, ACSL4, TfR) and iron levels across acute to chronic recovery phases. The therapeutic effects of atVNS were evaluated through the assessment of ferroptosis markers, neurogenesis, angiogenesis, cognitive function, and neuroinflammation. α7nAChR knockout mice were used to investigate the receptor's role in atVNS-mediated recovery.

RESULTS

We observed sustained alterations in ferroptosis markers and iron levels throughout post-stroke recovery. atVNS treatment reduced ferroptosis progression by modulating GPX4 and ACSL4 expression, enhanced neurogenesis and angiogenesis, improved cognitive recovery, and reduced neuroinflammation. These beneficial effects were absent in α7nAChR knockout mice, while atVNS increased neuronal α7nAChR expression in wild-type mice.

CONCLUSIONS

This study reveals the persistent involvement of ferroptosis in stroke recovery and demonstrates that atVNS provides comprehensive neuroprotection through α7nAChR-dependent mechanisms. These findings establish atVNS as a promising noninvasive therapeutic approach for stroke recovery and highlight α7nAChR signaling as a potential therapeutic target.

MAPK14 drives Ferroptosis and immune dysfunction in pediatric Sepsis-induced acute lung injury

OBJECTIVE

Sepsis-induced acute lung injury (ALI) is driven by inflammation, oxidative stress, and immune suppression. MAPK14 (p38α) plays a role in ferroptosis and immune regulation, but its specific function in pediatric sepsis remains unclear. Therefore, our study aimed to explore the role and underlying mechanism of MAPK14 in pediatric sepsis.

METHODS

Bioinformatics analysis of GSE26440 and FerrDb identified ferroptosis-related genes in pediatric sepsis. STRING database was used to predict the proteins associated with MAPK14. MAPK14 expression in whole blood samples, LPS-treated MLE-12 cells, and a CLP mouse model was detected by qRT-PCR and western blot. Ferroptosis was assessed by measuring MDA, GSH, and Fe2+ levels, while ROS accumulation was analyzed using DCFH-DA staining and DHE staining. A cycloheximide (CHX) assay was performed to assess TTP53 protein stability. MPO immunohistochemistry and PD-L1 immunofluorescence assessed neutrophil infiltration, and flow cytometry evaluated neutrophil apoptosis.

RESULTS

Bioinformatics analysis of GSE26440 and FerrDb identified MAPK14 as a ferroptosis-related gene in pediatric sepsis. MAPK14 expression was upregulated in sepsis patient samples, LPS-treated MLE-12 cells and CLP mouse lung tissues. Overexpression of MAPK14 led to increased MDA and Fe2+ levels, reduced GSH, and elevated ROS fluorescence intensity, confirming its role in promoting ferroptosis. Mechanistically, MAPK14 upregulated TTP53, which in turn suppressed SLC7A11 and GPX4, further driving ferroptosis. MAPK14 overexpression stabilized TTP53 and enhanced its activity. Additionally, MAPK14 enhanced MPO and PD-L1 expression to promote neutrophil infiltration and immune suppression. Additionally, MAPK14 overexpression inhibited neutrophil apoptosis, promoted neutrophil infiltration and enhanced immune suppression.

CONCLUSION

MAPK14 drives ferroptosis via the TTP53/SLC7A11/GPX4 pathway and exacerbates immune suppression by promoting neutrophil infiltration.

The role of protein lactylation in brain health and disease: current advances and future directions

Lactate, the end product of glycolysis, plays a crucial role in cellular signaling and metabolism. The discovery of lactylation, a novel post-translational modification, has uncovered the role of lactate in regulating diseases, especially in the brain. Lactylation connects genetic encoding with protein function, thereby influencing key biological processes. Increasing evidence supports lactate-mediated lactylation as a critical modulator in neurological disorders. This review offers an overview of lactate metabolism and lactylation, highlighting recent advances in understanding the regulatory enzymes of lactylation and their role in the central nervous system. We investigate the impact of lactylation on brain dysfunctions, including neurodegenerative diseases, cerebrovascular disorders, neuroinflammation, brain tumors, and psychiatric conditions. Moreover, we highlight the therapeutic potential of targeting lactylation in treating brain disorders and outline key research gaps and future directions needed to advance this promising field.

Multi-omic serum analysis reveals ferroptosis pathways and diagnostic molecular signatures associated with Moyamoya diseases

Moyamoya disease (MMD) is a rare cerebrovascular disease in humans. Although early revascularization can improve symptoms, it cannot reverse the progression of the disease. The current diagnosis still relies on traditional a Digital Subtraction Angiography (DSA) examination, which is invasive and expensive, leading to delayed diagnosis and affecting treatment timing and patient prognosis. The ability to diagnose MMD early and develop personalized treatment plans can significantly improve the prognosis of patients. Here, we have introduced the research on MMD biomarkers. By integrating proteomics and metabolomics data, we have successfully identified over 1700 features from more than 60 serum samples collected at the onset of symptoms in MMD patients. We use multiple computational strategies to interpret complex information in serum, providing a comprehensive perspective for early diagnosis of MMD. Diagnostic ability of our biomarker is significantly better than previous studies, especially when used in combination. In the study of molecular mechanisms, we found that the ferroptosis pathway was significant disruption in MMD patients, which was also confirmed by transcriptomics data. Finally, we validated the metabolites and proteins associated with ferroptosis pathways, as well as the biomarkers screened by machine learning, using another independent MMD cohort. Our research provides important clues for the diagnosis of MMD, and this assay can identify MMD early, thereby promoting stronger monitoring and intervention.

PGC-1α role in rescuing ferroptosis in cerebral ischemia/reperfusion injury through promoting mitochondrial biogenesis and UCP2 expression

Cerebral ischemia/reperfusion injury (CIRI) is a critical factor leading to adverse outcomes in acute ischemic stroke with reperfusion therapy. The occurrence of CIRI involves several cell death pathways, such as ferroptosis. Peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) a vital role in mitochondrial biogenesis and induces several crucial reactive oxygen species (ROS) detoxifying enzymes. Nonetheless, the role of activated PGC-1α in CIRI is still unclear. In this research, we utilized a PGC-1α agonist (ZLN005) in both in vitro and in vivo models of CIRI and found that ZLN005 ameliorates neurologic deficits, reduces infarct volume, and inhibits neuronal ferroptosis in CIRI. Furthermore, CIRI led to a decrease in neuronal mitochondrial quantity and downregulation of uncoupling protein 2 (UCP2) expression. Treatment with ZLN005 activated PGC-1α, promoted neuronal mitochondrial biogenesis, and upregulated UCP2 expression, thereby reducing mitochondrial oxidative stress. The application of the mitochondria-targeted antioxidant Mito-TEMPO inhibited ferroptosis, while UCP2 silencing induced mitochondrial oxidative stress and weakened ZLN005 inhibitory effect of ferroptosis, confirming the dependency of ferroptosis on mitochondrial oxidative stress in CIRI. According to these findings, targeting PGC-1α may offer an effective therapeutic strategy for CIRI by regulating mitochondrial homeostasis and protecting neurons from ferroptotic damage.

Developmental proteome dynamics in granulosa and thecal layers from growing follicles to pre-ovulatory duck follicles†

Granulosa and thecal layer cells play important roles in the post-hatching follicular growth in laying birds. To examine the biochemical processes of granulosa and thecal layers associated with follicular growth, the technique of data independent acquisition was used in this study to explore protein profiling in granulosa and thecal layers from growing follicles in laying ducks. We identified and quantitatively analyzed 8032 proteins in granulosa cells and 9552 proteins in thecal layer cells. Hierarchical clustering of the resulting profiles revealed differential changes of expression of proteins linked to cell metabolism, signaling, cell junction, especially in steroid synthesis, peroxisome proliferator-activated receptor, and gap junction signaling pathway at different stages of follicles. The highest expression of proteins related to gap junction and peroxisome proliferator-activated receptor signaling pathway occurred in granulosa cells of 3-6 mm or 6-8 mm follicles. In granulosa cells, decreases in the enzymes that catalyze the transformation of estrone into estradiol and proteins related to calcium transport and apoptosis occurred during follicular growth. As follicles grew, proteins related to androgens biosynthesis and involved in gap junction and peroxisome proliferator-activated receptor signaling pathway decreased in the thecal layer cells. Three main group functional clusters extracted from the protein-protein interaction network, were mainly responsible for apoptosis, steroid hormone biosynthesis, and the peroxisome proliferator-activated receptor signaling pathway. These proteomic data provide a holistic framework for understanding how diverse biochemical processes in granulosa cells and thecal layer cells are coordinated at the cellular level during follicular growth in laying birds.

Calcium/Calmodulin-Dependent Protein Kinase II β Regulates Autophagy Dependent Ferroptosis of Neurons after Cerebral Ischemic Injury by Activating the AREG/JUN/ELAVL1 Pathway

Ferroptosis is an iron-dependent regulatory cell death characterized by lipid peroxidation. The molecular mechanism of calcium/calmodulin-dependent protein kinase II β (CAMK2B) affecting cerebral ischemic injury through autophagy-dependent ferroptosis is still unclear. Here, we aimed to study the regulatory effect of CAMK2B on autophagy-dependent ferroptosis and its effect on cerebral ischemic injury. We found that CAMK2B was significantly upregulated in oxygen and glucose deprivation/recovery (OGD/R)-induced PC12 cells and primary hippocampal neurons. CAMK2B knockdown inhibited OGD/R-induced autophagy-dependent ferroptosis in PC12 cells and primary hippocampal neurons. In addition, CAMK2B was co-localized with amphiregulin (AREG) in PC12 cells, and overexpression of AREG reversed the effect of CAMK2B knockdown on OGD/R-induced autophagy-dependent ferroptosis in PC12 cells and primary hippocampal neurons. Further molecular mechanism studies showed that AREG enhanced the transcriptional activation of embryonic lethal abnormal vision-like 1 (ELAVL1) through Jun Proto-Oncogene (c-Jun), thereby inducing autophagy-dependent ferroptosis in PC12 cells and primary hippocampal neurons. Moreover, CAMK2B was significantly upregulated in the ipsilateral penumbra neurons of cerebral ischemia-reperfusion (I/R) mice, and the level of autophagy-dependent ferroptosis was increased in the brain tissue of I/R mice. Knockdown of CAMK2B alleviated neuronal damage by inhibiting autophagy-dependent ferroptosis in the brain tissue of model mice. This study suggests that CAMK2B plays a key role in regulating neuronal autophagy-dependent ferroptosis, and CAMK2B may be a potential target for the treatment of cerebral I/R injury.

ACSL3 is a promising therapeutic target for alleviating anxiety and depression in Alzheimer's disease

Alzheimer's disease (AD), the leading cause of dementia, affects over 55 million people worldwide and is often accompanied by depression and anxiety. Both significantly impact patients' quality of life and impose substantial societal and economic burdens on healthcare systems. Identifying the complex regulatory mechanisms that contribute to the psychological and emotional deficits in AD will provide promising therapeutic targets. Biosynthesis of omega-3 (ω3) and omega-6 fatty acids (ω6-FA) through long-chain acyl-CoA synthetases (ACSL) is crucial for cell function and survival. This is due to ω3/6-FA's imperative role in modulating the plasma membrane, energy production, and inflammation. While ACSL dysfunction is known to cause heart, liver, and kidney diseases, the role of ACSL in pathological conditions in the central nervous system (e.g., depression and anxiety) remains largely unexplored. The impact of ACSLs on AD-related depression and anxiety was investigated in a mouse model of Alzheimer's disease (3xTg-AD). ACSL3 levels were significantly reduced in the hippocampus of aged 3xTg-AD mice (via capillary-based immunoassay). This reduction in ACAL3 was closely associated with increased depression and anxiety-like behavior (via forced swim, tail suspension, elevated plus maze, and sucrose preference test). Upregulation of ACSL3 via adenovirus in aged 3xTg-AD mice led to increased protein levels of brain-derived neurotrophic factor (BDNF) and vascular endothelial growth factor C (VEGF-C) (via brain histology, capillary-based immunoassay), resulting in alleviation of depression and anxiety symptoms. The present study highlights a novel neuroprotective role of ACSL3 in the brain. Targeting ACSL3 will offer an innovative approach for treating AD-related depression and anxiety.

PLAGL2-STAU1-NCOA4 axis enhances gastric cancer peritoneal metastasis by resisting ferroptosis via ferritinophagy

Peritoneal metastasis (PM) is the primary site of distant metastasis in gastric cancer (GC) and is associated with an advanced disease stage and poor prognosis. Due to its high resistance to chemotherapy, disseminated peritoneal lesions are often untreatable. A primary reason for therapy resistance in cancer cells is often their defective cell death execution mechanisms. Ferroptosis, a newly identified type of regulated cell death, is strongly linked to the emergence and formation of tumors. Earlier studies have demonstrated the significant role of RNA-binding proteins in ferroptosis. Nevertheless, the fundamental process linking Staufen Double-Stranded RNA Binding Protein 1 (STAU1) to ferroptosis in the peritoneal metastasis of gastric cancer is yet to be clarified. This study shows that the RNA-binding protein STAU1 is crucial for regulating ferroptosis in gastric cancer cells. Elevated levels of STAU1 are linked to unfavorable outcomes in individuals diagnosed with gastric cancer. STAU1 was up-regulated by PLAGL2 and decreased the stability of NCOA4 mRNA by binding to the 3'-untranslated region. Decreased NCOA4 expression inhibits the accumulation of reactive iron, the occurrence of the Fenton reaction, and cellular ROS generation in the GC cells. Additionally, we showed that NCOA4 is crucial in the process of ferritinophagy triggered by the reduction of STAU1 in gastric cancer cells. Ultimately, the process safeguards GC cells from ferroptosis. These findings elucidate the function of PLAGL2/STAU1/NCOA4 in the ferroptosis of gastric cancer cells and provide theoretical backing for possible diagnostic markers and treatment targets for peritoneal metastasis in gastric cancer.

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.

Natural flavonoids from herbs and nutraceuticals as ferroptosis inhibitors in central nervous system diseases: current preclinical evidence and future perspectives

Flavonoids are a class of important polyphenolic compounds, renowned for their antioxidant properties. However, recent studies have uncovered an additional function of these natural flavonoids: their ability to inhibit ferroptosis. Ferroptosis is a key mechanism driving cell death in central nervous system (CNS) diseases, including both acute injuries and chronic neurodegenerative disorders, characterized by iron overload-induced lipid peroxidation and dysfunction of the antioxidant defense system. This review discusses the therapeutic potential of natural flavonoids from herbs and nutraceuticals as ferroptosis inhibitors in CNS diseases, focusing on their molecular mechanisms, summarizing findings from preclinical animal models, and providing insights for clinical translation. We specifically highlight natural flavonoids such as Baicalin, Baicalein, Chrysin, Vitexin, Galangin, Quercetin, Isoquercetin, Eriodictyol, Proanthocyanidin, (-)-epigallocatechin-3-gallate, Dihydromyricetin, Soybean Isoflavones, Calycosin, Icariside II, and Safflower Yellow, which have shown promising results in animal models of acute CNS injuries, including ischemic stroke, cerebral ischemia-reperfusion injury, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, and spinal cord injury. Among these, Baicalin and its precursor Baicalein stand out due to extensive research and favorable outcomes in acute injury models. Mechanistically, these flavonoids not only regulate the Nrf2/ARE pathway and activate GPX4/GSH-related antioxidant pathways but also modulate iron metabolism proteins, thereby alleviating iron overload and inhibiting ferroptosis. While flavonoids show promise as ferroptosis inhibitors for CNS diseases, especially in acute injury settings, further studies are needed to evaluate their efficacy, safety, pharmacokinetics, and blood-brain barrier penetration for clinical application.

The role of vitamin K and its antagonist in the process of ferroptosis-damaged RPE-mediated CNV

Age-related macular degeneration (AMD) is the leading cause of irreversible vision loss in people over the age of 55. AMD currently affects approximately 8% of the world's population, and the number is growing as the global population ages. Growing evidence suggests that pathological choroidal neovascularization (CNV) is often related to more severe and rapid vision loss and blindness associated with AMD. The typical clinical treatment is intravitreal injection of anti-vascular endothelial growth factor (anti-VEGF) agents. However, some patients do not respond well to this therapy, and the potential risks of long-term repeated injections cannot be ignored. Therefore, there is an urgent need to explore the specific mechanisms of CNV development and find new, safe, and effective treatments. In this study, our data indicate that ferroptotic damage of retinal pigment epithelium (RPE) and its induced VEGFA overexpression are critical promoting factors in the development of CNV. Vitamin K can mediate the protection of RPE cells from ferroptotic damage and regulate the expression of eIF2α-ATF4-VEGFA in a VKOR/FSP1-dependent manner, inhibiting new angiogenesis to alleviate CNV. On the contrary, vitamin K antagonists (VKA) represented by warfarin, can promote RPE ferroptotic damage and related vascular proliferation in mice and eventually aggravate CNV lesions. However, vitamin K still showed significant protective effects even in the presence of VKA. Due to its significant anti-ferroptosis and anti-neovascular effects, as well as its relative safety and convenience of use, vitamin K has excellent potential in the treatment of CNV and is expected to become a clinically effective and safe new CNV treatment strategy.

Laminin-dystroglycan mediated ferroptosis in hemorrhagic shock and reperfusion induced-cognitive impairment through AMPK/Nrf2

Hemorrhagic shock and reperfusion (HSR) is the main cause of death following trauma. Cognitive impairment may persist after successful resuscitation from hemorrhagic shock, but the mechanisms remain elusive. This study demonstrated the presence of ferroptosis in an in vitro model of oxygen-glucose deprivation and reoxygenation (OGD/R) in HT22 neurons, and also in a murine model of HSR using 3-month-old C57BL/6 mice. The ferroptosis induced by OGD/R was characterized by transmission electron microscopy, the localization of FTH1 and TFR1 in HT22 cells. However, neuronal ferroptosis was prevented by suppressing AMPK through siRNA transfection or AMPK inhibitor pretreatment (compound C) in vitro. There was a consistent increase in Nrf2 with ROS accumulation, iron deposition, and lipid peroxidation in the hippocampal neurons and tissues. Nrf2 knockdown or overexpression significantly modulated OGD/R induced-ferroptosis. Activating ferroptosis by erastin (a ferroptosis inducer) or inhibiting it by ferrostatin-1 (a ferroptosis inhibitor) respectively enhanced or mitigated cognitive deficits as well as the ferroptosis-related changes induced by HSR. In addition to the improved cognition, single-nucleus transcriptome analysis of ipsilateral hippocampi from Nrf2-/- mice demonstrated the broad decrease of ferroptosis in neuronal cell clusters. LAMA2 and DAG1 were dominantly elevated and co-localized in the hippocampal CA3 region of Nrf2-/- mice by fluorescence in situ hybridization. The activation of astrocytes was significantly attenuated after Nrf2 knockout, associated with the increases of laminin-dystroglycan during astrocyte-neuron crosstalk. Thus, data from this study proposes a novel explanation, namely laminin-dystroglycan interactions during astrocytes-neurons crosstalk stimulating AMPK and Nrf2 induced neuronal ferroptosis, for the development of cognitive impairment after HSR.

Resveratrol alleviates testicular toxicity induced by anti-PD-1 through regulating the NRF2-SLC7A11-GPX4 pathway

Background

Fertility preservation is a critical concern for reproductive-age cancer survivors, as conventional cytotoxic therapies can cause irreversible damage to the reproductive system, potentially depriving them of the ability to have children in the future. Immune checkpoint inhibitors (ICIs), including anti-programmed cell death protein 1 (anti-PD-1), have become a standard therapeutic approach for various malignancies. However, the impact of ICIs on reproductive function and fertility is not well understood and remains a largely unexplored domain. Resveratrol (RSV), a plant-derived compound, has shown potential as an nuclear factor erythroid 2-related factor 2 (NRF2) agonist to counteract reproductive toxicity induced by various diseases, drugs, and environmental toxins.

Methods

Male C57BL6/J mice with B16 melanoma were assigned into four groups. RSV and ICI/RSV groups received RSV (40 mg/kg) orally every other day for one month, while controls received the vehicle. ICI and ICI/RSV groups were injected with anti-PD-1 antibody (10 mg/kg) weekly, and controls received IgG2b kappa antibody. Parameters like body and testicular weight, sperm concentration, and western blot for ferroptosis markers were measured. Furthermore, oxidative stress biomarkers, lipid oxidation factors, and gonadal hormone levels were quantified using commercial kits.

Results

Anti-PD-1 therapy caused male reproductive dysfunction, as evidenced by reduced sperm concentration, altered gonadal hormone levels, and disruption of blood-testis barrier (BTB) integrity. Furthermore, ferroptosis was a key mechanism in anti-PD-1-induced testicular dysfunction, characterized by disrupted iron homeostasis, elevated lipid peroxidation, and suppression of the system Xc-/glutathione peroxidase 4 (GPX4) axis. Additionally, anti-PD-1 therapy diminished antioxidant defenses by inhibiting the NRF2 pathway, thereby increasing the susceptibility to ferroptosis. Crucially, RSV treatment ameliorated anti-PD-1-induced reproductive dysfunction. This was achieved by reducing T cell infiltration, lowering interferon-gamma levels, activating the NRF2 pathway, and maintaining iron and lipid homeostasis.

Conclusions

Our study demonstrates that anti-PD-1 triggers oxidative stress and ferroptosis in the testis, causing male reproductive dysfunction. RSV may offer protection against testicular toxicity associated with anti-PD-1, particularly through its antioxidant and anti-ferroptosis properties.

Spatial metabolic analysis of the regulatory effects of DL-3-n-butylphthalide in a cerebral ischemia-reperfusion mouse model

DL-3-n-butylphthalide (NBP) exhibits promising pharmacological efficacy against ischemia-reperfusion injury, but its protective effects may involve many mechanisms that are yet to be fully understood. This study aimed to profile the metabolic alterations induced by NBP during the process of ischemia-reperfusion using spatial metabolomics. Our study found that NBP could significantly reduce the ischemic area and restore physical function by potentially modulating pathways of the citrate cycle, pyruvate metabolism, autophagy, and unsaturated fatty acid biosynthesis. During the process of ischemia-reperfusion, NBP played a therapeutic role in improving energy supply, decreasing autophagy, and improving unsaturated fatty acid biosynthesis. Subsequent studies confirmed improvements in relevant indices of mitochondrial morphology, autophagy, and ferroptosis after treatment with NBP. These findings shed light on novel mechanisms underlying the efficacy of NBP in treating cerebral ischemia/reperfusion injury associated with ischemic stroke.

Aerobic Exercise Activates Fibroblast Growth Factor 21 and Alleviates Cardiac Ischemia/Reperfusion-induced Neuronal Oxidative Stress and Ferroptosis in Paraventricular Nucleus

Cardiac ischemia/reperfusion (I/R) induces systemic oxidative stress, which in turn gives rise to the development of multiple organ abnormalities, including brain injury. The paraventricular nucleus (PVN) of the hypothalamus is a cardiovascular regulatory center. Aerobic exercise is an effective intervention to protect the heart against I/R injury. However, the effect of aerobic exercise on cardiac I/R-induced neuronal injury in the PVN has not been fully elucidated. The aim of this study is to investigate whether aerobic exercise can up-regulate fibroblast growth factor 21 (FGF21) and alleviate neuronal oxidative stress and ferroptosis in the PVN caused by cardiac I/R. In vivo, after six weeks of aerobic exercise, the cardiac I/R model was established by ligating the left anterior descending (LAD) coronary artery for 30 min, followed by 2 h of reperfusion. Cardiac function and heart rate variability (HRV) were measured. Morphological changes, oxidative stress, expression of FGF21 and its downstream signaling molecules, as well as ferroptosis-related indicators in the PVN, were evaluated. In vitro, HT22 cells were exposed to oxygen-glucose deprivation and reoxygenation (OGD/R) and treated with recombinant human FGF21 (rhFGF21) and compound C to elucidate the potential mechanism. Cardiac I/R induced iron deposition, elevated expression of lipid peroxidation drivers, and impaired antioxidant capacity in the PVN, which collectively contributed to neuronal ferroptosis. Aerobic exercise up-regulated the expression of FGF21, FGFR1, and PGC-1α, maintained the phosphorylation of AMPKα, enhanced antioxidant capacity, reduced ROS and lipid peroxidation, regulated iron homeostasis, and effectively attenuated neuronal ferroptosis induced by cardiac I/R. In addition, rhFGF21 protected HT22 cells against OGD/R-induced oxidative stress and ferroptosis, which was blocked by AMPK inhibition. FGF21 plays a pivotal role in regulating neuronal oxidative stress and ferroptosis. Aerobic exercise could increase the expression of FGF21, FGFR1, and PGC-1α, maintain the phosphorylation of AMPKα, and alleviate cardiac I/R-induced neuronal oxidative stress and ferroptosis. These results confirm the protective effect of aerobic exercise against cardiac I/R-induced brain injury and provide an experimental basis for studying the relationship between exercise and the "heart-brain axis."

The emerging role and therapeutical implications of ferroptosis in wound healing

Wound healing is a complex biological process involving multiple steps, including hemostasis, inflammation, proliferation, and remodeling. A novel form of regulated cell death, ferroptosis, has garnered attention because of its involvement in these processes. Ferroptosis is characterized by the accumulation of lipid peroxides and is tightly regulated by lipid metabolism, iron metabolism, and the lipid-peroxide repair network, all of which exert a significant influence on wound healing. This review highlights the current findings and emerging concepts regarding the multifaceted roles of ferroptosis throughout the stages of normal and chronic wound healing. Additionally, the potential of targeted interventions aimed at modulating ferroptosis to improve wound-healing outcomes is discussed.

Bovine milk-derived extracellular vesicles reduce oxidative stress and ferroptosis induced by Klebsiella pneumoniae in bovine mammary epithelial cells

BACKGROUND

Ferroptosis is characterized by increased production of reactive oxygen species (ROS) and membrane lipid peroxidation that can exacerbate inflammatory damage. Extracellular vesicles (EVs) isolated from bovine milk have many biological functions, including antioxidant properties. However, the role of EVs on Klebsiella pneumoniae-induced ferroptosis and oxidative stress in bovine mammary epithelial cells (bMECs) and murine mammary tissue is unclear. In this study, EVs were isolated from bovine colostrum, mature milk and clinical mastitis milk (defined as C-EVs, M-EVs and CM-EVs, respectively) and assessed by transmission electron microscopy, Western blot and transcriptome sequencing. Effects of EVs on K. pneumoniae-induced ferroptosis and oxidative stress in bMECs were evaluated with immunofluorescence and Western blot.

RESULTS

In bMECs, infection with K. pneumoniae induced oxidative stress, decreasing protein expression of Nrf2, Keap1 and HO-1 plus SOD activity, and increasing ROS concentrations. However, protein expression of GPX4, ACSL4 and S100A4 in bMECs, all factors that regulate ferroptosis, was downregulated by K. pneumoniae. Furthermore, this bacterium compromised tight junctions in murine mammary tissue, with low expression of ZO-1 and Occludin, whereas protein expression of Nrf2 and GPX4 was also decreased in mammary tissue. Adding C-EVs, M-EVs or CM-EVs reduced oxidative stress and ferroptosis in K. pneumoniae-infected bMECs in vitro and murine mammary tissues in vivo.

CONCLUSION

In conclusion, all 3 sources of milk-derived EVs alleviated oxidative stress and ferroptosis in K. pneumoniae-infected bMECs and mammary tissues.

Microglial HO-1 aggravates neuronal ferroptosis via regulating iron metabolism and inflammation in the early stage after intracerebral hemorrhage

Heme oxygenase 1 (HO-1), an enzyme involved in heme catabolism, has been shown upregulated in microglia cells and plays a critical roles in neurological damages after intracerebral hemorrhage (ICH). However, the mechanisms by which HO-1 mediates the neuronal damages are still obscure. Here, our findings demonstrate that HO-1 over-expression exacerbates the pro-inflammatory response of microglia and induces neuronal ferroptosis through promoting intracellular iron deposition in the ICH model both in vitro and in vivo. Furthermore, in the co-cultured ICH model in vitro, we verify that HO-1 over-expression disrupts the balance of iron metabolism in microglia, which increases the iron efflux to the extracellular space and promotes iron ion uptake in neurons, leading to lipid peroxidation injury and further contributing to neuronal ferroptosis. Moreover, the specific ferroptosis inhibitor Ferrostatin-1 (Fer-1) treatment could mitigate the damages in the co-cultured HT22 cells that caused by HO-1 over-expression in microglia, and improve the neurological function in the ICH model in mice. By shedding light on the mechanisms of aggravating neuronal ferroptosis due to HO-1 overexpression in the early stages after ICH, our study provides insights into the potential therapy of targeting HO-1 to treat ICH.

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.

Activation of PAR1 contributes to ferroptosis of Schwann cells and inhibits regeneration of myelin sheath after sciatic nerve crush injury in rats via Hippo-YAP/ACSL4 pathway

OBJECTIVE

Peripheral nerve injury (PNI) is characterized by high incidence and sequela rate. Recently, there was increasing evidence that has shown ferroptosis may impede functional recovery. Our objective is to explore the novel mechanism that regulates ferroptosis after PNI.

METHODS

LC-MS/MS proteomics was used to explore the possible differential signals, while PCR array was performed to investigate the differential factors. Besides, we also tried to activate or inhibit the key factors and then observe the level of ferroptosis. Regeneration of myelin sheath was finally examined in vivo via transmission electron microscopy.

RESULTS

Proteomics analysis suggested coagulation signal was activated after sciatic nerve crush injury, in which high expression of F2 (encoding thrombin) and F2r (encoding PAR1) were observed. Both thrombin and PAR1-targeted activator TRAP6 can induce ferroptosis in RSC96 cells, which can be rescued by Vorapaxar (PAR1 targeted inhibitor) in vitro. Further PCR array revealed that activation of PAR1 induced ferroptosis in RSC96 cells by increasing expression of YAP and ACSL4. Immunofluorescence of sciatic nerve confirmed that the expression of YAP and ACSL4 were simultaneously reduced after PAR1 inhibition, which may contribute to myelin regeneration after injury in SD rats.

CONCLUSION

Inhibition of PAR1 can relieve ferroptosis after sciatic nerve crush injury in SD rats through Hippo-YAP/ACSL4 pathway, thereby regulating myelin regeneration after injury. In summary, PAR1/Hippo-YAP/ACSL4 pathway may be a promising therapeutic target for promoting functional recovery post-sciatic crush injury.

Regulated cell death in acute myocardial infarction: Molecular mechanisms and therapeutic implications

Acute myocardial infarction (AMI), primarily caused by coronary atherosclerosis, initiates a series of events that culminate in the obstruction of coronary arteries, resulting in severe myocardial ischemia and hypoxia. The subsequent myocardial ischemia/reperfusion (I/R) injury further aggravates cardiac damage, leading to a decline in heart function and the risk of life-threatening complications. The complex interplay of multiple regulated cell death (RCD) pathways plays a pivotal role in the pathogenesis of AMI. Each RCD pathway is orchestrated by a symphony of molecular regulatory mechanisms, highlighting the dynamic changes and critical roles of key effector molecules. Strategic disruption or inhibition of these molecular targets offers a tantalizing prospect for mitigating or even averting the onset of RCD, thereby limiting the extensive loss of cardiomyocytes and the progression of detrimental myocardial fibrosis. This review systematically summarizes the mechanisms underlying various forms of RCD, provides an in-depth exploration of the pathogenesis of AMI through the lens of RCD, and highlights a range of promising therapeutic targets that hold the potential to revolutionize the management of AMI.

Important molecular mechanisms in ferroptosis

Ferroptosis is a type of cell death that is caused by the oxidation of lipids and is dependent on the presence of iron. It was first characterized by Brent R. Stockwell in 2012, and since then, research in the field of ferroptosis has rapidly expanded. The process of ferroptosis-induced cell death is genetically, biochemically, and morphologically distinct from other forms of cellular death, such as apoptosis, necroptosis, and non-programmed cell death. Extensive research has been devoted to comprehending the intricate process of ferroptosis and the various factors that contribute to it. While the majority of these studies have focused on examining the effects of lipid metabolism and mitochondria on ferroptosis, recent findings have highlighted the significant involvement of signaling pathways and associated proteins, including Nrf2, P53, and YAP/TAZ, in this process. This review provides a concise summary of the crucial signaling pathways associated with ferroptosis based on relevant studies. It also elaborates on the drugs that have been employed in recent years to treat ferroptosis-related diseases by targeting the relevant signaling pathways. The established and potential therapeutic targets for ferroptosis-related diseases, such as cancer and ischemic heart disease, are systematically addressed.

SMAD1 Regulates the Hippocampal Neuronal Death and Ferroptosis via Affecting the Transcription of PDCD4 in Cerebral Ischemia

Results of previous studies suggested that programmed cell death 4 (PDCD4) was overexpressed in cerebral ischemia (CI), and mothers against decapentaplegic homolog 1 (SMAD1) is a transcription factor of PDCD4, and it is also elevated in CI; however, the regulatory mechanism of SMAD1/PDCD4 axis in CI remains unclear. The current work has been designed to explore the role and associated mechanisms of SMAD1/PDCD4 in CI. PDCD4 and SMAD1 expressions have been examined by real-time reverse transcription-polymerase chain reaction (RT-qPCR) method, and receiver operating characteristic (ROC) curve analysis has been performed to determine the potential diagnostic value of PDCD4 and SMAD1. An oxygen-glucose deprivation (OGD) model has been used to investigate the effects of PDCD4 and SMAD1 on CI in vitro. Cell apoptosis was evaluated using TdT-mediated dUTP nick end labeling (TUNEL) assays. The interaction between SMAD1 and PDCD4 axis has been confirmed by using dual-luciferase reporter as well as chromatin immunoprecipitation (Ch-IP) assays. Finally, the effects of SMAD1/PDCD4 axis on the ferroptosis of neuron cells have been examined. PDCD4 was overexpressed in blood samples of CI patients. ROC analysis showed the AUC for PDCD4 was 0.7478, and NIHSS and MRS scores were positively correlated with PDCD4 expression. Moreover, the cellular OGD model was established and knockdown of PDCD4 suppressed the apoptosis of neurons. Besides, knockdown of PDCD4 also inhibited ferroptosis of OGD-treated neuron cells in vitro. Additionally, SMAD1 was upregulated in blood samples of CI patients, NIHSS and MRS scores were positively correlated with SMAD1 expression, and SMAD1 is a transcriptional factor of PDCD4, and SMAD1 could transcriptionally regulate the expression of PDCD4. Finally, SMAD1 could regulate the ferroptosis of neuron cells through regulating the transcription of PDCD4. The SMAD1/PDCD4 axis regulates the growth, apoptosis, and ferroptosis of neuron cells, suggesting that targeting the SMAD1/PDCD4 axis may be a potential therapeutic method.

SS-31@Fer-1 Alleviates ferroptosis in hypoxia/reoxygenation cardiomyocytes via mitochondrial targeting

PURPOSE

Targeting mitochondrial ferroptosis presents a promising strategy for mitigating myocardial ischemia-reperfusion (I/R) injury. This study aims to evaluate the efficacy of the mitochondrial-targeted ferroptosis inhibitor SS-31@Fer-1 (elamipretide@ferrostatin1) in reducing myocardial I/R injury.

METHODS

SS-31@Fer-1 was synthesized and applied to H9C2 cells subjected to hypoxia/reoxygenation (H/R) to assess its protective effects. Cytotoxicity was evaluated using a cell counting kit-8 (CCK-8) assay, with lactate dehydrogenase (LDH) and creatine kinase isoenzyme (CK-MB) levels measured. Mitochondrial reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were assessed using Mito-SOX and JC-1 fluorescent dyes, respectively. Lipid peroxidation products, malondialdehyde (MDA) and glutathione (GSH), were quantified. Mitochondrial structure, mt-cytochrome b (mt-Cytb), and mt-ATP synthase membrane subunit 6 (mt-ATP6) were analyzed. Additionally, iron homeostasis and ferroptosis markers were evaluated.

RESULTS

SS-31@Fer-1 significantly improved H/R-induced cardiomyocyte viability and reduced LDH and CK-MB levels. Compared to the Fer-1 group, SS-31@Fer-1 reduced GSH and increased MDA levels, enhancing mitochondrial integrity and function. Notably, it increased mitochondrial ROS and decreased MMP, indicating a mitigation of H/R-induced cardiomyocyte cytotoxicity. Furthermore, SS-31@Fer-1 maintained cellular iron homeostasis, as evidenced by increased expression of FTH, FTMT, FPN, and ABCB8. Elevated levels of GPX4 and Nrf2 were observed, while ACSL4 and PTGS2 levels were reduced in the SS-31@Fer-1 group.

CONCLUSIONS

SS-31@Fer-1 effectively suppressed ferroptosis in H/R-induced cardiomyocytes by maintaining cellular iron homeostasis, improving mitochondrial function, and inhibiting oxidative stress. These findings provide novel insights and opportunities for alleviating myocardial I/R injury.

TNFSF9 Silence Impedes Cerebral Ischemia-Reperfusion Injury via Modulating SLC3A2 Expression in Brain Microvascular Endothelial Cells

Cerebral ischemia-reperfusion injury (CIRI), which stays unresolved in the clinic, occurs after recanalization of blood vessels serving brain tissues in acute ischemic stroke patients and can result in massive brain cell death, and cell ferroptosis contributes greatly to this process. Our research firstly found that TNFSF9 expression harbored diagnostic value on CIRI patients and intended to further investigate its regulatory mechanism in CIRI, which might facilitate its diagnostic and therapeutic application in the clinic. The level of TNSF9 mRNA was augmented in the plasma of CIR patients, and its silence impeded ferroptosis, apoptosis, and release of inflammatory mediators of BMECs with OGD/R treatment. Besides, SP1 positively regulated TNFSF9 expression as one of its transcription factors, and TNFSF9 overexpression reversed SP1 silence-mediated inhibition on ferroptosis, apoptosis, and release of inflammatory mediators in OGD/R-treated BMECs. In addition, silencing SLC3A2 could neutralize the benefit effects of TNFSF9 downregulation on BMECs under OGD/R context in vitro, and silencing TNFSF9 neutralized necrotic volumes in rat brain induced by CIRI via modulating SLC3A2 expression in vivo. TNFSF9 regulated by SP1 aggravated CIRI via boosting ferroptosis, apoptosis, and release of inflammatory mediators of BMECs under OGD/R situation by suppressing SLC3A2 expression in vitro and in vivo.

A Supramolecular Deferoxamine-Crisaborole Nanoparticle Targets Ferroptosis, Inflammation, and Oxidative Stress in the Treatment of Retinal Ischemia/Reperfusion Injury

Retinal ischemia-reperfusion (IR) injury is a major cause of vision loss worldwide, with ferroptosis, oxidative stress, and inflammation playing key roles in its pathogenesis. Currently, treatments targeting multiple aspects of this condition are limited. This study introduces a supramolecular nanoparticle combining the phosphodiesterase 4 (PDE4) inhibitor crisaborole and the ferroptosis inhibitor deferoxamine to address these pathological processes. Crisaborole forms a dynamic bond with deferoxamine via benzoxaborole-catechol chemistry, creating an amphiphilic molecule that assembles into nanoparticles. Treatment with these nanoparticles enhances glutathione peroxidase 4 (GPX4) levels, downregulates ferroptosis-related genes [Acyl-CoA synthetase long chain family member 4 (Acsl4), heme oxygenase 1 (Hmox1)], reduces inflammatory markers (interleukin-1 beta, interleukin-6, tumor necrosis factor alpha), and decreases reactive oxygen species. Electroretinogram and histochemical analysis confirm the nanoparticles' superior protective effects compared to control treatments. This study proposes a novel nanoparticle approach for retinal IR injury by simultaneously targeting multiple pathogenic pathways.

Intranasal iron administration induces iron deposition, immunoactivation, and cell-specific vulnerability in the olfactory bulb of C57BL/6 mice

Iron is the most abundant transition metal in the brain and is essential for brain development and neuronal function; however, its abnormal accumulation is also implicated in various neurological disorders. The olfactory bulb (OB), an early target in neurodegenerative diseases, acts as a gateway for environmental toxins and contains diverse neuronal populations with distinct roles. This study explored the cell-specific vulnerability to iron in the OB using a mouse model of intranasal administration of ferric ammonium citrate (FAC). Olfactory function was assessed through olfactory discrimination tests, while iron levels in OB tissues, cerebrospinal fluid (CSF), and serum were quantified using inductively coupled plasma mass spectrometry (ICP-MS), immunohistochemical staining, and iron assays. Transcriptomic changes and immune responses were assessed using RNA sequencing and immune cell infiltration analysis. Results showed that intranasal FAC administration impaired olfactory function, accompanied by iron deposition in the olfactory mucosa and OB, as well as damage to olfactory sensory neurons. Notably, these effects occurred without elevations in CSF or serum iron levels. OB iron accumulation activated multiple immune cells, including microglia and astrocytes, but did not trigger ferroptosis. Spatial transcriptomic sequencing of healthy adult mouse OBs revealed significant cellular heterogeneity, with an abundance of neuroglia and neurons. Among neurons, GABAergic neurons were the most prevalent, followed by glutamatergic and dopaminergic neurons, while cholinergic and serotonergic neurons were sparsely distributed. Under iron-stressed conditions, oligodendrocytes, dopaminergic neurons, and glutamatergic neurons exhibited significant damage, while GABAergic neurons remained unaffected. These findings highlight the selective vulnerability of neuronal and glial populations to iron-induced stress, offering novel insights into the loss of specific cell types in the OB during iron dysregulation.

Aptamer biosensors for thrombin

Thrombin, a key factor in the coagulation cascade, is a valuable biomarker of great importance for the prognosis, diagnosis, and monitoring of various diseases, including cancer and heart disease. Due to the increasing attention to the development of point-of-care testing (POCT) options, various types of biosensors have been invented to enhance the accuracy and speed of detection of important biomarkers such as thrombin. Implementation of aptamers in biosensors (aptasensors) improves the target recognition capacity due to the high-affinity binding nature of aptamers. Herein, this review presents recent studies of aptasensors for thrombin detection based on different detection mechanisms encompassing optical biosensors, surface-enhanced Raman spectroscopy (SERS), electrochemical detection, piezoelectric detection, and lateral flow assay.

Integrated Analysis and Validation of Ferroptosis-Related Genes Associated with Ischemia/Reperfusion Injury in Lung Transplantation

Background

Lung transplantation is the only effective therapeutic option for patients with end-stage lung disease. However, ischemia/reperfusion injury (IRI) during transplantation is a leading cause of primary graft dysfunction (PGD). Ferroptosis, a form of iron-dependent cell death driven by lipid peroxidation, has been implicated in IRI across various organs. This study aims to explore the role of ferroptosis in lung transplantation-related ischemia/reperfusion injury and to identify its potential molecular mechanisms through bioinformatics analysis.

Methods

Transcriptome data from lung transplant patients were obtained from the Gene Expression Omnibus (GEO) database. Ferroptosis-related differentially expressed genes (FRGs) were identified by analyzing gene expression profiles before and after reperfusion. Weighted gene co-expression network analysis (WGCNA) was used to identify module genes, and overlapping genes were further analyzed using two machine learning algorithms. The CIBERSORT algorithm was applied to assess immune cell infiltration, while Mendelian randomization (MR) analysis was used to investigate causal relationships between candidate genes and PGD. Finally, Consensus clustering based on FRGs was performed to identify subtypes.

Results

We identified four candidate genes associated with ferroptosis during lung reperfusion: tumor necrosis factor alpha-induced protein 3 (TNFAIP3), C-X-C motif chemokine ligand 2 (CXCL2), neural precursor cell expressed developmentally down-regulated 4-like (NEDD4L), and sestrin 2 (SESN2). These genes were closely associated with immune cell infiltration. MR analysis suggested that SESN2 might play a protective role against PGD. Additionally, consensus clustering revealed distinct immune infiltration patterns across subtypes, providing insights for personalized therapeutic approaches to lung ischemia/reperfusion injury (LIRI).

Conclusion

This study highlights TNFAIP3, CXCL2, NEDD4L, and SESN2 as candidate genes associated with ferroptosis during LIRI, with SESN2 potentially protecting against PGD. These findings offer promising therapeutic targets for preventing LIRI and improving outcomes in lung transplantation.

Simvastatin-Induced Ferroptosis in Orbital Fibroblasts in Graves' Ophthalmopathy

Purpose

Graves' ophthalmopathy (GO), the most common extrathyroidal manifestation of Graves' disease, is disabling and disfiguring. Recent studies have shown that statins have a protective effect on individuals with GO. Statins were reported to trigger ferroptosis in some disorders, but little is known about whether statins protect against GO via ferroptosis. The aim of this study was to explore whether ferroptosis is involved in the protective effect of simvastatin on GO.

Methods

GO-OFs, which are orbital fibroblasts (OFs) derived from individuals with GO, were analyzed for lipogenesis by RT-qPCR and Red Oil O staining posttreatment with simvastatin. CCK-8 assays, flow cytometric analysis, and transmission electron microscopy (TEM) were used to compare the sensitivity of GO-OFs and control-OFs to erastin-induced ferroptosis. The ferroptosis levels in the GO-OFs were evaluated by measuring cell viability, reactive oxygen species (ROS) levels, and lipid peroxidation levels and performing TEM analysis after treatment with simvastatin and Fer-1.

Results

The GO-OFs were resistant to erastin-induced ferroptosis. The viability and lipogenesis of the GO-OFs were significantly decreased, while the levels of ROS, lipid peroxidation, and the ferroptosis marker ACLS4 were increased upon treatment with simvastatin.

Conclusions

Our study indicated that ferroptosis plays an important role in the pathogenesis of GO and that simvastatin may induce ferroptosis, suggesting that this drug could serve as a novel therapeutic agent for GO.

EGCG attenuated spinal cord injury by inhibiting ferroptosis via activation of HMOX1 expression and suppression of HIF-1 signaling pathway

Objectives

Epigallocatechin gallate (EGCG) exhibits various biological effects, including antiviral, anti-inflammatory, cardioprotective, and lipid-regulating properties. This study aims to investigate the therapeutic effects and mechanisms of EGCG in spinal cord injury (SCI).

Materials and Methods

The bioinformatic databases were used to screen therapeutic target genes for drugs against SCI. Component-Target-Disease networks were constructed with Cytoscape software, and inter-target interactions were analyzed using the String database. Additionally, KEGG pathway enrichment analyses were conducted on the identified target genes. SCI was evaluated by detecting inflammation-related factors, H&E staining, and immunohistochemistry. Furthermore, ROS and JC1 staining were performed on HT22 cells subjected to various treatments. Molecular mechanisms were investigated using western blot and qRT-PCR analyses.

Results

Forty-four overlapping genes were identified as potential targets, with HMOX1, GPX-4, and HIF-1A emerging as central hub genes. Key pathways associated with these targets included Ferroptosis and HIF-1 signaling. In vivo studies demonstrated that EGCG effectively promotes motor function recovery and reduces the expression of proteins and genes such as IL-1β, IL-6, HIF-1α, and 4HNE. In vitro experiments showed that EGCG decreases ROS and intracellular lipid ROS levels in HT22 cells while increasing GPX-4 and HMOX1 expression to inhibit ferroptosis and HIF-1 signaling pathways.

Conclusion

Our findings reveal a significant new mechanism by which EGCG can reduce SCI through the inhibition of ferroptosis, facilitated by the activation of HMOX1 expression and the down-regulation of the HIF-1 signaling pathway. This suggests its potential as a therapeutic option for this condition.

Nrf2 and Ferroptosis: Exploring Translational Avenues for Therapeutic Approaches to Neurological Diseases

Nrf2, a crucial protein involved in defense mechanisms, particularly oxidative stress, plays a significant role in neurological diseases (NDs) by reducing oxidative stress and inflammation. NDs, including Alzheimer's, Parkinson's, Huntington's, amyotrophic lateral sclerosis, stroke, epilepsy, schizophrenia, depression, and autism, exhibit ferroptosis, iron-dependent regulated cell death resulting from lipid and iron-dependent reactive oxygen species (ROS) accumulation. Nrf2 has been shown to play a critical role in regulating ferroptosis in NDs. Age-related decline in Nrf2 expression and its target genes (HO-1, Nqo-1, and Trx) coincides with increased iron-mediated cell death, leading to ND onset. The modulation of iron-dependent cell death and ferroptosis by Nrf2 through various cellular and molecular mechanisms offers a potential therapeutic pathway for understanding the pathological processes underlying these NDs. This review emphasizes the mechanistic role of Nrf2 and ferroptosis in multiple NDs, providing valuable insights for future research and therapeutic approaches.

Ferroptosis in organ ischemia-reperfusion injuries: recent advancements and strategies

Ferroptosis is a newly discovered type of regulated cell death participated in multiple diseases. Different from other classical cell death programs such as necrosis and apoptosis, ferroptosis involving iron-catalyzed lipid peroxidation is characterized by Fe2+ accumulation and mitochondria alterations. The phenomenon of oxidative stress following organ ischemia-reperfusion (I/R) has recently garnered attention for its connection to the onset of ferroptosis and subsequent reperfusion injuries. This article provides a comprehensive overview underlying the mechanisms of ferroptosis, with a further focus on the latest research progress regarding interference with ferroptotic pathways in organ I/R injuries, such as intestine, lung, heart, kidney, liver, and brain. Understanding the links between ferroptosis and I/R injury may inform potential therapeutic strategies and targeted agents.

Gastrodin: Modulating the xCT/GPX4 and ACSL4/LPCAT3 pathways to inhibit ferroptosis after ischemic stroke

Ischemic stroke ranks as the second leading cause of global mortality and disability. Although reperfusion is crucial for salvaging brain tissue, it carries the risk of secondary injuries, such as ferroptosis. Gastrodin, a neuroprotective compound found in Chinese herbal medicine, may regulate this process. However, its impact on stroke-induced ferroptosis remains unclear.

OBJECTIVE

This research endeavors to probe Gastrodin's influence on post-ischemic ferroptosis, deciphering its mechanisms and assessing its therapeutic promise.

METHODS

We developed rat models of middle cerebral artery occlusion/reperfusion (MCAO/R) and created oxygen-glucose deprivation/reoxygenation (OGD/R)-damaged PC12 cell models. Gastrodin was administered to assess ferroptosis using Prussian blue staining and fluorescence probes. To investigate the effects of gastrodin on the xCT/GPX4 and ACSL4/LPCAT3 pathways, we employed molecular docking, immunofluorescence, Western blotting, and quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, we used transmission electron microscopy and JC-1 fluorescence probes to examine mitochondrial integrity and function.

RESULTS

Our study demonstrated that gastrodin significantly reduced iron accumulation and lipid peroxidation in the brains of MCAO/R rats and OGD/R-injured PC12 cells. It suppressed reactive oxygen species (ROS) and ameliorated mitochondrial membrane potential. It potentiates the xCT/GPX4 axis while repressing the ACSL4/LPCAT3 pathway, leading to improved mitochondrial architecture and function, notably characterized by decreased mitochondrial membrane potential, reduced ROS levels, and increased formation of mitochondrial cristae. By modulating the xCT/GPX4 and ACSL4/LPCAT3 pathways, gastrodin mitigated ferroptosis in ischemic stroke, thereby preserving mitochondrial structural and functional integrity. This study provides novel mechanistic insights into gastrodin's therapeutic potential for treating ischemic stroke, highlighting the importance of traditional Chinese medicine in modern medical therapy.

YTHDF2 influences hepatic fibrosis by regulating ferroptosis in hepatic stellate cells by mediating the expression of ACSL4 in an m 6A-dependent manner

Hepatic fibrosis (HF) is an abnormal reparative response of the liver to chronic injury and is histologically reversible. In recent years, increasing interest has been given to changes in m 6A in liver disease. In this study, we explore the role of the m 6A-modified reading protein YTHDF2 in HF and its regulatory mechanism. The HF mouse model is generated through CCl 4 injection, and the cell model is via TGF-β stimulation. The liver tissues are subjected to hematoxylin-eosin, Masson, and α-SMA immunohistochemical staining. Reactive oxygen species (ROS) and iron levels are examined via relevant kits. Quantitative real-time PCR, immunofluorescence staining, and western blot analysis were conducted to measure the YTHDF2 and ACSL4 levels. RNA immunoprecipitation, methylated RNA immunoprecipitation, RNA pull-down, and polysome fractionation were performed to understand the regulatory mechanism by which YTHDF2 affects ACSL4. The results show that YTHDF2 is highly expressed after HF induction, and the inhibition of YTHDF2 reduces fibrosis as well as ROS and iron levels. In vitro, overexpression of YTHDF2 increases hepatic stellate cell activation, as well as ROS and iron levels, and this effect is blocked by the silencing of ACSL4. YTHDF2 acts as a regulator of ACSL4 expression and is involved in m 6A modification. In addition, in vivo experiments indicate that overexpression of ACSL4 reverses the attenuating effect of YTHDF2 interference on HFs. Therefore, YTHDF2 mediates the expression of the ferroptosis marker protein ACSL4 in an m 6A-dependent manner, thereby affecting HF.

Identification and Validation of Ferroptosis Related Genes in Ischemic Stroke and Its Effect on the Peripheral Immune Landscape

Background

This research utilized a combination of gene databases associated with ferroptosis and online gene expression data from ischemic stroke samples to pinpoint ferroptosis-related genes (FRGs) in ischemic stroke cases.

Methods

By employing Random Forest (RF) and Support Vector Machine (SVM) models based on these genes, an overlap of genes from both models was identified as "Hub" genes. Through consensus clustering analysis using Hub genes, two distinct clusters of FRGs were revealed in ischemic stroke samples. Examination of the correlation between these molecular subtypes and the immune microenvironment highlighted a close link between gene expression levels and immune cell infiltration. Significantly different gene expression and functions within the FRG clusters underscored the pivotal role of Hub genes in the immune microenvironment. A gene diagnostic model related to ferroptosis was developed and validated to elucidate the significance of the identified genes.

Results

The results demonstrated that the Hub gene-based classification model effectively differentiated between ischemic stroke patients and normal samples, achieving an AUC of 0.900, signifying clinical relevance.

Conclusion

This study successfully identified ferroptosis-related genes in ischemic stroke, offering insights that could contribute to the formulation of future comprehensive treatment approaches.

BMAL1 alleviates sepsis-induced AKI by inhibiting ferroptosis

BACKGROUND

The role of BMAL1 in various diseases remains unclear, particularly its impact on sepsis-induced acute kidney injury (AKI). This study aims to investigate the role of BMAL1 in sepsis-induced AKI and its potential effects on cell ferroptosis. Initially, we assessed BMAL1 expression levels in mice treated with sepsis-induced AKI (via LPS injection) and in LPS-stimulated renal tubular epithelial cells. Subsequently, we explored the correlation between BMAL1 and ferroptosis using sequencing technology, validating our findings throughout experimental approaches. To further elucidate BMAL1's specific effects on AKI-related ferroptosis, we constructed BMAL1 overexpression models in mice and cells, analysing its impact on AKI and ferroptosis both in vivo and in vitro. Furthermore, using transcriptome sequencing technology, we identified key BMAL1-regulated genes and their associated biological pathways, validating these findings through in vivo and in vitro experiments.

RESULTS

Our findings indicate decreased BMAL1 expression in sepsis-induced AKI. BMAL1 overexpression effectively mitigated renal tubular injury by reducing ferroptosis levels in renal tubular epithelial cells. Using transcriptome sequencing and ChIP-qPCR technology, we identified YAP as a target of BMAL1. The overexpression of BMAL1 significantly reduced the transcriptional activity of YAP and inhibited the Hippo signalling pathway. Treatment with the Hippo inhibitor Verteporfin (VP) reversed the BMAL1-downregulation-induced damage. Additionally, our study revealed that YAP positively regulates ACSL4 gene expression and its downstream signalling pathways.

CONCLUSION

This study demonstrates that BMAL1 overexpression alleviates renal tubular epithelial cell injury and ferroptosis by inhibiting YAP expression and the Hippo pathway, thereby exerting protective effects in sepsis-induced AKI. These findings underscore the therapeutic potential of targeting BMAL1 in managing sepsis-induced AKI.

Sirtuin1 Suppresses Calcium Oxalate Nephropathy via Inhibition of Renal Proximal Tubular Cell Ferroptosis Through PGC-1α-mediated Transcriptional Coactivation

Calcium oxalate (CaOx) crystals induce renal tubular epithelial cell injury and subsequent nephropathy. However, the underlying mechanisms remain unclear. In the present study, single-cell transcriptome sequencing is performed on kidney samples from mice with CaOx nephrocalcinosis. Renal proximal tubular cells are identified as the most severely damaged cell population and are accompanied by elevated ferroptosis. Further studies demonstrated that sirtuin1 (Sirt1) effectively reduced ferroptosis and CaOx crystal-induced kidney injury in a glutathione peroxidase 4 (GPX4)-dependent manner. Mechanistically, Sirt1 relies on peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) to promote resistance to ferroptosis in the tubular epithelium, and PGC-1α can recruit nuclear factor erythroid 2-related factor 2 (NRF2) to the promoter region of GPX4 and co-activate GPX4 transcription. This work provides new insight into the mechanism of CaOx crystal-induced kidney injury and identifies Sirt1 and PGC-1α as potential preventative and therapeutic targets for crystal nephropathies.