Ferroptosis contributes to hypoxic-ischemic brain injury in neonatal rats: Role of the SIRT1/Nrf2/GPx4 signaling pathway

MiR-4472 serves as a potential biomarker for hypoxic-ischemic encephalopathy and promotes neuronal death as well as hypoxic-ischemic brain damage in neonatal rats by targeting MEF2D

BACKGROUND

Hypoxic-ischemic encephalopathy (HIE) is a predominant cause in neonatal mortality and long-term neurological impairment. Accumulating evidence underscores the pivotal involvement of microRNAs (miRNAs) in HIE. Our prior miRNA microarray analysis revealed elevated miR-4472 levels in plasma from HIE newborns. However, the diagnostic potential of miR-4472 for HIE and its mechanistic contributions to disease progression remain to be elucidated.

METHODS

We collected plasma samples from HIE and healthy newborns, qRT-PCR and receiver operating characteristic (ROC) curve analyses were employed to evaluate miR-4472 expression and diagnostic performance, respectively. An in vitro HIE model was established using oxygen-glucose deprivation and reperfusion (OGD/R)-treated SH-SY5Y cells, while an in vivo HIE model was generated by subjecting seven days old male SD rats to carotid artery ligation followed by hypoxia. Neurological function in HIE neonatal rats was assessed using the Zea-Longa scoring system and Morris Water Maze tests, whereas brain tissue pathology and apoptosis were analyzed through HE staining and TUNEL assays, respectively. The targeting relationship between miR-4472 and MEF2D was validated via western blotting and dual-luciferase reporter assays. CCK-8 and Annexin V-FITC/PI staining were utilized to elucidate the effects of miR-4472 on SH-SY5Y cell viability and apoptosis through MEF2D. ELISA and commercial kits were used to quantify inflammatory factors, ROS, and MDA levels.

RESULTS

Our study demonstrated that miR-4472 was significantly elevated in plasma from HIE newborns, OGD/R-treated SH-SY5Y cells, and brain tissue of HIE rats, with higher levels observed in moderate-to-severe cases compared to mild HIE, the area under curve (AUC) of miR-4472 for HIE diagnosis reaching 0.958. Inhibition of miR-4472 restored cell viability and reduced apoptosis in OGD/R-treated SH-SY5Y cells, improved neurological function and ameliorated brain damage in HIE rats. Mechanistically, miR-4472 directly targets and suppresses MEF2D expression, thereby increasing ROS and MDA levels, inducing the expression and release of IL-6, TNF-α, and IL-1β. Intervention with MEF2D effectively antagonized the effects of miR-4472 in HIE.

CONCLUSION

This study demonstrates that plasma miR-4472 serves as a potential diagnostic biomarker for HIE and promotes its pathological progression by targeting MEF2D.

Ferroptosis, necroptosis, and pyroptosis in calcium oxalate crystal-induced kidney injury

Kidney stones represent a highly prevalent urological disorder worldwide, with high incidence and recurrence rates. Calcium oxalate (CaOx) crystal-induced kidney injury serves as the foundational mechanism for the formation and progression of CaOx stones. Regulated cell death (RCD) such as ferroptosis, necroptosis, and pyroptosis are essential in the pathophysiological process of kidney injury. Ferroptosis, a newly discovered RCD, is characterized by its reliance on iron-mediated lipid peroxidation. Necroptosis, a widely studied programmed necrosis, initiates with a necrotic phenotype that resembles apoptosis in appearance. Pyroptosis, a type of RCD that involves the gasdermin protein, is accompanied by inflammation and immune response. In recent years, increasing amounts of evidence has demonstrated that ferroptosis, necroptosis, and pyroptosis are significant pathophysiological processes involved in CaOx crystal-induced kidney injury. Herein, we summed up the roles of ferroptosis, necroptosis, and pyroptosis in CaOx crystal-induced kidney injury. Furthermore, we delved into the curative potential of ferroptosis, necroptosis, and pyroptosis in CaOx crystal-induced kidney injury.

Inhibition of Ferroptosis Attenuates Neuron Damage and Improves Cognitive Impairment in Mice Surviving Severe Hypothermia

Survivors of severe hypothermia frequently exhibit cognitive impairments. However, the underlying mechanisms remain inadequately understood. In order to reveal the scientific problem of cognitive dysfunction caused by severe hypothermia, providing an experimental basis for clinical treatment, this study utilized animal models and combined cognitive behavioral, morphological, and molecular biological experiments. The results showed that severe hypothermia leads to an accumulation of iron ions in the cerebral cortex tissue exceeding 70%, while increased Acyl-coenzyme A synthetase long-chain family member 4 (ACSL4) expression enhances sensitivity to ferroptosis. This process results in a nearly 50% decrease in glutathione (GSH) expression and over 50% degradation of glutathione peroxidase 4 (GPX4), leading to GPX4 deactivation and increased lipid peroxidation, which in turn nearly doubles the levels of oxidative products such as MDA and 4NHE. Notably, ferroptosis inhibition using Ferrostatin-1 (Fer-1) effectively mitigates the degenerative death of cerebral cortical neurons induced by severe hypothermia, significantly improving the associated cognitive deficits. These findings suggest that severe hypothermia may induce ferroptosis in cortical neurons through the Nrf2/SLC7A11/GSH/GPX4 signaling axis. Targeted inhibition of ferroptosis has the potential to be a promising therapeutic direction for the prevention and treatment of cognitive impairment caused by severe hypothermia.

Influence of Sevoflurane Postconditioning on Hypoxic-Ischemic Brain Injury via Nrf2-Regulated Ferroptosis in Neonatal Rats

BACKGROUND

The mechanisms by which sevoflurane protects the brain from hypoxic-ischemic brain injury (HIBI) are unknown. Ferroptosis occurs during HIBI and is regulated by the nuclear factor erythroid 2-related factor 2 (Nrf2). This study investigated the roles of Nrf2-regulated ferroptosis in sevoflurane postconditioning (SPC)-mediated neuroprotection during HIBI.

METHODS

HIBI was induced in 7-day-old rats. SPC (2.5%, 30 minutes) was performed immediately after HIBI, and some rats were injected with ML385 (an Nrf2-inhibitor) 30 minutes before HIBI. Ferroptosis was evaluated by measuring glutathione peroxidase 4 (GPx4), solute carrier family 7 member 11 (SLC7A11, also known as xCT), glutathione (GSH), cysteine, iron, malondialdehyde (MDA) levels, and mitochondrial morphology. Nrf2 and heme oxygenase-1 (HO-1) expression were determined to explore the signaling pathways involved in SPC-mediated neuroprotection. Brain morphology, left/right hemisphere weight ratios, and Nissl staining were measured to assess brain damage. The Morris water maze was conducted to assess long-term learning and memory abilities.

RESULTS

SPC alleviated HIBI-induced cysteine depletion-induced (HIBI versus SPC, xCT/β-tubulin ratio: -0.435 [95% CI, -0.727 to -0.143], P = .003; Cysteine (% of Sham): -29.8 [95% CI, -39.4 to -20.2], P < .001; GSH (% of Sham): -46.5 [95% CI, -54.6 to -38.4], P < .001) and GPx4 inhibition-induced ferroptosis (HIBI versus SPC, GPx4/β-tubulin ratio: -0.287 [95% CI, -0.514 to -0.0603], P = .01). Compared with the HIBI group, the SPC group showed improved learning and memory abilities (HIBI versus SPC, platform crossings: -4 times [95% CI, -7 to -1], P = .002; escape latency: 46 seconds [95% CI, 24 to 68], P < .001), reduced brain damage (HIBI versus SPC, weight ratio of left/right cerebral hemispheres: -13.1 [95% CI, -15.7 to -10.4], P < .001; neuronal density ratio: -0.450 [-0.620 to -0.280], P < .001), and increased Nrf2 and HO-1 protein levels (HIBI versus SPC, Nrf2/β-tubulin ratio: -1.89 [95% CI, -2.82 to -0.970], P < .001; HO-1/β-tubulin ratio: -1.08 [95% CI, -1.73 to -0.442], P < .001). Inhibiting Nrf2 via ML385 partly reversed SPC-mediated neuroprotection (SPC versus SPC+ML385, weight ratio of left/right cerebral hemispheres: 12.4 [95% CI, 9.73-15.1], P < .001; neuronal density ratio: 0.412 [95% CI, 0.242-0.582], P < .001), accompanied by decreased HO-1 expression (SPC versus SPC+ML385, HO-1/β-tubulin ratio: 1.70 [95% CI, 1.05-2.34], P < .001).

CONCLUSIONS

SPC inhibits both cysteine depletion- and GPx4 inhibition-induced ferroptosis by regulating Nrf2/HO-1 signaling to protect against HIBI.

L-theanine prevents myocardial injury in sleep‑deprived mice by suppressing ferroptosis through SIRT1

Green tea is obtained from Camellia sinensis, and its role in promoting heart health has been widely recognized in traditional Chinese medicine. L-theanine, one of the main bioactive components of green tea, has antioxidant and cardiovascular protective effects. However, the effects of L-theanine on myocardial cells in sleep-deprived mice and its potential mechanisms have not been clearly elucidated. This study utilized a modified multiple-platform water environment method to establish an SD model and induce a ferroptosis model in H9c2 cells pretreated with erastin. The cardiac function parameters of mice were assessed using a small animal super-resolution ultrasound imaging system. H&E staining was used to evaluate pathological changes in tissue structure and cell morphology, while transmission electron microscopy (TEM) was employed to observe the extent of mitochondrial damage. Biochemical assays were employed to quantify myocardial damage markers, oxidative stress indicators, and Fe2⁺ concentrations, while immunofluorescence imaging assessed reactive oxygen species (ROS) levels. Western blot was used to analyze the expression of SIRT1 and proteins related to ferroptosis. The results demonstrate that L-theanine alleviates SD-induced tachycardia in mice, restores myocardial and mitochondrial integrity, and reduces oxidative damage markers, including ROS and Fe2⁺ in H9c2 cells. Furthermore, L-theanine reversed the abnormal expression of SIRT1 and ferroptosis-related proteins in cardiac tissue and H9c2 cells induced by SD and erastin. Notably, the SIRT1 inhibitor EX-527 can counteract the protective effect of L-theanine against ferroptosis in cardiomyocytes. These findings highlight that L-theanine mitigates SD-induced cardiac injury primarily by suppressing ferroptosis through SIRT1 in cardiomyocytes.

Decreased serum SLC7A11 and GPX4 levels may reflect disease severity of acute ischaemic stroke

ObjectiveThis study aimed to examine the levels of solute carrier family seven number 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) in the serum of patients with acute ischaemic stroke (AIS) and their relationship with disease severity.MethodsA total of 148 patients with AIS together with 148 healthy controls (HCs) were enrolled. The expression levels of SLC7A11 and GPX4 in serum were detected immediately as early as possible. Radiographic severity was detected by Alberta Stroke Program Early CT Score (ASPECTS). Disease severity was evaluated using modified Rankin Scale (mRS). High-sensitivity C-reactive protein (hs-CRP) and matrix metalloproteinase-9 (MMP-9) expression levels were also measured. A correlation analysis was conducted to determine the relationship between the expression levels of SLC7A11 and GPX4 with the clinical severity of the disease and the levels of hs-CRP and MMP-9. Furthermore, receiver operating characteristic (ROC) curve analysis was utilized to assess the potential of SLC7A11 and GPX4 as diagnostic markers.ResultsCompared to the HC group, the serum expression levels of SLC7A11 and GPX4 were significantly lower in the AIS group. Serum SLC7A11 levels were positively associated with serum GPX4 levels. The AIS group included 50 patients with mild neurological impairment, 52 with moderate neurological impairment, and 46 with severe neurological impairment. AIS patients with mild neurological impairment had drastically higher serum SLC7A11 and GPX4 levels compared with those with moderate neurological impairment. AIS patients with moderate neurological impairment showed significantly higher serum SLC7A11 and GPX4 concentrations compared with those with severe neurological impairment. ROC curve analysis demonstrated that both serum SLC7A11 and GPX4 may both act as potential indicators for evaluating of AIS disease severity. In addition, both serum SLC7A11 and GPX4 levels were positively correlated with ASPECTS. Both serum SLC7A11 and GPX4 levels were negatively associated with hs-CRP as well as MMP-9 levels. Serum SLC7A11 and GPX4 levels were significantly increased following comprehensive therapy.ConclusionsDecreased SLC7A11 and GPX4 levels may reflect disease severity of AIS.

Role of sirtuins in cerebral ischemia-reperfusion injury: Mechanisms and therapeutic potential

The high incidence and mortality rate of cardiac arrest (CA) establishes it as a critical clinical challenge in emergency medicine globally. Despite continuous advances in advanced life support (ALS) technology, the prognosis for patients experiencing cardiac arrest remains poor, with cerebral ischemia and reperfusion injury (CIRI) being a significant determinant of adverse neurological outcomes and increased mortality. Sirtuins (SIRTs) are a class of highly evolutionarily conserved NAD+-dependent histone deacylenzymes capable of regulating the expression of various cytoprotective genes to play a neuroprotective role in CIRI. SIRTs mainly regulate the levels of downstream proteins such as PGC 1-α, Nrf 2, NLRP 3, FoxOs, and PINK 1 to inhibit inflammatory response, attenuate oxidative stress, improve mitochondrial dysfunction, promote angiogenesis, and inhibit apoptosis while reducing CIRI. Natural active ingredients are widely used in regulating the protein level of SIRTs in the body because of their multi-components, multi-pathway, multi-target, and minimal toxic side effects. However, these naturally active ingredients still face many challenges related to drug targeting, pharmacokinetic properties, and drug delivery. The emergence and vigorous development of new drug delivery systems, such as nanoparticles, micromilk, and exosomes, provide strong support for solving the above problems. In the context of the rapid development of molecular biology technology, non-coding RNA (NcRNA), represented by miRNA and LncRNA, offers great potential for achieving gene-level precision medicine. In the context of multidisciplinary integration, combining SIRTs proteins with biotechnology, omics technologies, artificial intelligence, and material science will strongly promote the deepening of their basic research and expand their clinical application. This review describes the major signaling pathways of targeting SIRTs to mitigate CIRI, as well as the current research status of Chinese and Western medicine and medical means for the intervention level of SIRTs. Meanwhile, the challenges and possible solutions in the clinical application of targeted drugs are summarized. In the context of medical and industrial crossover, the development direction of SIRTs in the future is discussed to provide valuable reference for basic medical researchers and clinicians to improve the clinical diagnosis and treatment effects of CIRI.

Tectorigenin mitigates homocysteine-induced inflammation and ferroptosis in BV-2 microglial cells through promoting the SIRT1/SLC7A11 pathway

Ferroptosis and inflammation are central to the pathophysiology of hyperhomocysteinemia (HHcy)-associated neurological disorders. Tectorigenin, a natural flavonoid aglycone extracted from numerous plants, possesses antioxidant, anti-inflammatory, and neuroprotective properties. This study aimed to investigate whether tectorigenin mitigates elevated homocysteine (Hcy)-induced toxicity in BV-2 microglial cells, focusing on its effects on inflammation and ferroptosis. Cell viability, lactate dehydrogenase (LDH) release, and proliferation assays were employed to evaluate cell injury. Inflammatory cytokines levels were determined by ELISA. Ferroptosis markers, including reactive oxygen species (ROS), lipid ROS, malondialdehyde (MDA), 4-hydroxy-nonenal (4-HNE), mitochondrial membrane potential (MMP), ATP, Fe2 + content, antioxidant enzymes (superoxide dismutase [SOD] and catalase [CAT]) activities were evaluated. mRNA and protein expressions were analyzed by qRT-PCR and western blotting, respectively. Our findings revealed that tectorigenin pretreatment significantly alleviated Hcy-induced cell injury and inflammatory response in BV-2 microglial cells. Furthermore, tectorigenin pretreatment reduced lipid peroxidation, enhanced antioxidant capacity, and alleviated ferroptotic cell death in Hcy-treated cells. Importantly, ferroptosis inhibitor Fer-1 also alleviated Hcy-induced cell injury and inflammation. Mechanistically, tectorigenin pretreatment activated the SIRT1/SLC7A11 pathway, and silencing SIRT1 reversed its protective effects. Collectively, these results indicate that tectorigenin attenuates Hcy-induced microglial injury by inhibiting inflammation and ferroptosis through the activation of the SIRT1/SLC7A11 pathway.

Preconditioning and Posttreatment Strategies in Neonatal Hypoxic-Ischemic Encephalopathy: Recent Advances and Clinical Challenges

Neonatal hypoxic-ischemic encephalopathy (HIE) is a severe neurological disorder caused by impaired cerebral blood flow and brain hypoxia, resulting in high morbidity and mortality rates. While therapeutic hypothermia remains the standard treatment and has been shown to reduce mortality to some extent, its therapeutic efficacy is limited, and it applies only to a select group of neonates who meet stringent inclusion criteria. Advances in our understanding of the pathophysiology of HIE have led to the identification of several promising neuroprotective strategies designed to mitigate or prevent the neurological damage induced by hypoxia-ischemia. Among these, preconditioning has emerged as a potent neuroprotective approach, enhancing cellular resilience to subsequent injury and potentially reducing treatment complexity and healthcare costs. Preconditioning/pretreatment and posttreatment offer significant promise in attenuating the neurological damage associated with HIE. Thus, exploring early intervention strategies for neonatal HIE, focusing on the comparative mechanisms and therapeutic targets of preconditioning and postconditioning, is critical to developing more effective treatment modalities. This review summarizes the current understanding of the pathophysiological mechanisms underlying neonatal HIE and its prevention and treatment strategies, providing new perspectives and a theoretical foundation for future neuroprotective interventions.

Dexmedetomidine Improves Long-term Neurological Outcomes by Promoting Oligodendrocyte Genesis and Myelination in Neonatal Rats Following Hypoxic-ischemic Brain Injury

Neonatal hypoxic-ischemic brain injury (HIBI) can lead to white matter damage, which significantly contributes to cognitive dysfunction, emotional disorders, and sensorimotor impairments. Although dexmedetomidine enhances neurobehavioral outcomes, its impact on oligodendrocyte genesis and myelination following hypoxic-ischemic events, as well as the underlying mechanisms, remain poorly understood. Dexmedetomidine was administered 15 min post-HIBI. We assessed neurobehavioral deficits using various tests: surface righting, negative geotaxis, forelimb grip strength, cliff avoidance, sensory reflexes, novel object recognition, T-maze, and three-chamber social interaction. We also investigated the relationship between myelination and neurobehavioral outcomes. Measurements included oligodendrocyte precursor cell (OPC) proliferation and survival 24 h post-injury, early myelination, and oligodendrocyte differentiation by postnatal day 14. Furthermore, we evaluated microglial activation towards the M2 phenotype and the extent of neuroinflammation during the acute phase. Dexmedetomidine significantly ameliorated long-term neurological deficits caused by HIBI. Pearson linear regression analysis revealed a strong correlation between long-term neurological outcomes and myelin maturity. The treatment notably mitigated the long-term deterioration of myelin formation and maturation following HIBI. This protective effect was primarily due to enhanced OPC proliferation and survival post-HIBI during the acute phase and, to a lesser extent, to the modulation of microglial activity towards the M2 phenotype and a reduction in neuroinflammation. Dexmedetomidine offers substantial protection against long-term neurobehavioral disabilities induced by HIBI, primarily by revitalizing the impaired survival and maturation of oligodendrocyte progenitor cells and promoting myelination.

Thymoquinone alleviates the accumulation of ROS and pyroptosis and promotes perforator skin flap survival through SIRT1/NF-κB pathway

Perforator flap transplantation is an important technique in flap reconstructive surgery, but flap necrosis limits its clinical effectiveness. Thymoquinone (TQ), a natural bioactive plant quinone found in black seed, exhibits anti-inflammatory, angiogenic, and antimicrobial properties. This study investigates the therapeutic effects of TQ in a perforator flap model through in vivo and in vitro experiments. Human umbilical vein endothelial cells (HUVECs) were treated with Tert-butyl Hydroperoxide (TBHP) to simulate an in vitro flap model and were then treated with TQ. In vivo experiments used a rat perforator flap model, and vascularization was assessed using Doppler ultrasound on days 3 and 7 after flap creation. On day 7 post-surgery, flap samples were collected to evaluate vascularity, reactive oxygen species, apoptosis and pyroptosis. Network pharmacology analysis was conducted to identify relevant signaling pathways, and molecular docking techniques were used to predict potential target binding sites. In vitro results showed that both TQ treatment and NLRP3 inhibitors reduced the expression of pyroptosis-related proteins. In vivo results indicated that the TQ-treated group had increased flap survival area, blood flow intensity, and microvascular density, while oxidative stress, apoptosis, and pyroptosis levels were reduced. Angiogenesis was enhanced, and expression of the SIRT1 protein was increased, while the p-P65/NF-κB/NLRP3 pathway was downregulated. After treatment with a SIRT1 inhibitor, flap survival rate and angiogenesis were reduced. These findings suggest that TQ improves perforator flap survival by inhibiting the NF-κB/NLRP3 pathway and promoting angiogenesis.

Targeting sirtuins in neurological disorders: A comprehensive review

The sirtuin (SIRT) family is a group of seven conserved nicotinamide adenine dinucleotide-dependent histone deacetylases (SIRT1-SIRT7), which play crucial roles in various fundamental biological processes, including metabolism, aging, stress responses, inflammation, and cell survival. The role of SIRTs in neuro-pathophysiology has recently attracted significant attention. Notably, SIRT1-SIRT3 have been identified as key players in neuroprotection as they reduce neuroinflammation and regulate mitochondrial function. This review summarizes the latest research advancements in the role of the SIRT family in neurological diseases, mainly including neurodegenerative diseases, ischemia-related diseases, bleeding-related diseases, nervous system injury and other nervous system diseases, emphasizing their critical functions and associated signaling pathways, (e.g., AMPK/SIRT1/PGC-1α, AMPK/SIRT1/IL-1β/NF-κB, STAT2-SIRT4-mTOR, SIRT3/FOXO3α, and other signaling pathways in disease progression, particularly their protective roles in neurodegenerative diseases, ischemic injuries, and neural damage. Additionally, this review discusses progress in clinical studies targeting SIRT-specific small-molecule agonists and inhibitors. Further research on SIRTs may provide new insights into potential therapeutic strategies for the prevention and treatment of neurological disorders.

SIRT1 Alleviates Mitochondrial Fission and Necroptosis in Cerebral Ischemia/Reperfusion Injury via SIRT1-RIP1 Signaling Pathway

Programmed cell death, including necroptosis, plays a critical role in the pathogenesis of cerebral ischemia/reperfusion injury (CIRI). Silent information regulator 1 (SIRT1) has been identified as a potential therapeutic target for CIRI, yet its precise role in regulating necroptosis remains controversial. Furthermore, the potential interaction between SIRT1 and receptor-interacting protein kinase 1 (RIP1) in this context is not fully understood. Sanpian Decoction (SPD), a classical traditional herbal formula, was previously shown to enhance SIRT1 expression in our studies. Our findings demonstrated that, both in vivo and in vitro, CIRI was associated with a decrease in SIRT1 levels and phosphorylated dynamin-related protein 1 (p-DRP1) at Ser637, alongside an increase in RIP1 and other necroptosis-related proteins. Co-immunoprecipitation and immunofluorescence analyses revealed a weakened interaction between SIRT1 and RIP1. Furthermore, abnormal mitochondrial fission and dysfunction were mediated through the phosphoglycerate mutase 5-DRP1 pathway. Notably, SPD treatment improved neurological outcomes and reversed these pathological changes by enhancing the SIRT1-RIP1 interaction. In conclusion, this study suggests that SIRT1 is a promising therapeutic target for CIRI, capable of inhibiting necroptosis and mitigating mitochondrial fission via the SIRT1-RIP1 pathway. SPD exhibits therapeutic potential by activating SIRT1, thereby attenuating necroptosis and mitochondrial fission during CIRI.

Bee Pollen Potential to Modulate Ferroptosis: Phytochemical Insights for Age-Related Diseases

Bee pollen (BP) is one of the richest known natural resources of micronutrients and bioactive phytochemicals. Some captivating bioactivities of BP compounds, although being largely investigated for the latter as individual molecules, remain very scarcely investigated or completely uninvestigated in bee pollen as a whole product. Among the most intriguing of these bioactivities, we identified ferroptosis as a major one. Ferroptosis, a recently discovered form of cell death (connecting oxidative stress and inflammation), is a complex pathophysiological process and one of the most crucial and perplexing events in current challenging human diseases such as cancer, neurodegeneration, and general aging diseases. Many BP compounds were found to intricately modulate ferroptosis depending on the cellular context by inducing this cell death mechanism in malignant cells and preventing it in non-malignant cells. Since research in both fields, i.e., BP and ferroptosis, is still recent, we deemed it necessary to undertake this review to figure out the extent of BP potential in modulating ferroptosis mechanisms. Our research proved that a wide range of BP compounds (polyphenols, phenolamides, carotenoids, vitamins, minerals, and others) substantially modulate diverse ferroptosis mechanisms. Accordingly, these phytochemicals and nutrients showed interesting potential in preclinical studies to lead to ferroptosis-mediated outcomes in important pathophysiological processes, including many aging-related disorders. One of the most paramount challenges that remain to be resolved is to determine how different BP compounds act on ferroptosis in different biological and pathophysiological contexts, either through synergistic or antagonistic behaviors. We hope that our current work constitutes a valuable incentive for future investigations in this promising and very relevant research avenue.

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

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

Ligustrazine hydrochloride Prevents Ferroptosis by Activating the NRF2 Signaling Pathway in a High-Altitude Cerebral Edema Rat Model

High-altitude cerebral edema (HACE) is a disorder caused by low pressure and hypoxia at high altitudes. Nevertheless, as of now, there is still a scarcity of safe and effective prevention and treatment methods. The active component of Ligusticum Chuanxiong, namely Ligustrazine hydrochloride (LH), has shown potential in the prevention and treatment of HACE due to its anti-inflammatory, antioxidant, and neuroprotective effects in nervous system disorders. Consequently, the potential protective effect of LH on HACE and its mechanism still need to be further explored. Prior to modeling, 90 male Sprague-Dawley rats were pretreated with different doses of drugs, including LH (100 mg/kg and 50 mg/kg), dexamethasone (4 mg/kg), and ML385 (30 mg/kg). Subsequently, the pretreated rats were placed in a low-pressure anoxic chamber simulating a plateau environment to establish the rat HACE model. The effects and mechanisms of LH on HACE rats were further elucidated through determination of brain water content, HE staining, ELISA, immunofluorescence, molecular docking, molecular dynamics simulation, western blot, and other techniques. The results showed, first of all, that LH pretreatment can effectively reduce brain water content; down-regulate the expression of AQP4, HIF-1α, and VEGF proteins; and alleviate damage to brain tissue and nerve cells. Secondly, compared with the HACE group, LH pretreatment can significantly reduce MDA levels and increase GSH and SOD levels. Additionally, LH decreased the levels of inflammatory factors IL-1β, IL-6, and TNF-α; reduced total iron content in brain tissue; increased the expression of ferroptosis-related proteins such as SLC7A11, GPX4, and FTH1; and alleviated ferroptosis occurrence. Molecular docking and molecular dynamics simulations show that LH has a strong binding affinity for NRF2 signaling. Western blot analysis further confirmed that LH promotes the translocation of NRF2 from the cytoplasm to the nucleus and activates the NRF2 signaling pathway to exert an antioxidant effect. The NRF2 inhibitor ML385 can reverse the anti-oxidative stress effect of LH and its protective effect on HACE rat brain tissue. In summary, LH may have a protective effect on HACE rats by activating the NRF2 signaling pathway, inhibiting ferroptosis, and resisting oxidative stress.

Anti-ferroptotic effects of natural polyphenols in nervous system injury: a narrative literature review

BACKGROUND

Recent studies have shown that ferroptosis, a newly identified regulated cell death characterized by increased lipid peroxidation and accumulation of toxic lipid peroxides, is closely related to the pathophysiological processes of nervous system diseases which can be inhibited with iron chelators, lipophilic antioxidants, and lipid peroxidation inhibitors.

OBJECTIVE

To review the current evidence on the efficacy of various natural polyphenols in nervous system injury.

METHODS

The data selected for this review were collected by searching the MEDLINE/PubMed, Web of Science, Scopus, and Google Scholar database for articles published in English between 2000 and 2024 using the following terms: cell death, regulated cell death, ferroptosis, lipid peroxides, iron, and glutathione peroxidase.

RESULTS

Natural polyphenols have been found to have some protective effects against nervous system disorders, which are attributed to a variety of biological properties, particularly antioxidant, immunomodulatory, and anti-inflammatory effects. The preclinical studies conducted on the use of the most common dietary polyphenols, including resveratrol, EGCG, curcumin, quercetin, gastrodin, baicalein & baicalin, carthamin, galangin, puerarin, morachalcone, and carnosic acid with the molecular mechanisms have been discussed. On the other hand, the results of a few clinical studies emphasize the primary role of iron in neuronal degeneration following some of nervous system injury.

CONCLUSION

Some of the findings indicated that natural polyphenols as antioxidant supplements have anti-ferroptotic effects in nervous system disorders.

Sevoflurane postconditioning mitigates neuronal hypoxic-ischemic injury via regulating reactive astrocytic STAT3 protein modification

Astrocyte activation plays a pivotal role in accelerating the cascade of neuroinflammation associated with the development of hypoxic-ischemic brain injury. This study aimed to investigate the mechanism by which sevoflurane postconditioning mitigates neuronal damage through astrocytes by regulating reactive astrocytic Signal Transducer and Activator of Transcription 3 (STAT3) modifications. A modified Rice‒Vannucci model in rats and a conditioned culture system established by subjecting primary astrocytes to oxygen glucose deprivation, followed by using the conditioned medium to culture the neuron cell line SH-SY5Y were used to simulate HI insult in vivo and in vitro, respectively. These models were followed by 30 min of 2.5 % sevoflurane treatment. Stattic was used to inhibit STAT3 phosphorylation, and (Z)-PUGNAc or OSMI-1 was added to regulate O-linked-β-N-acetylglucosamine modification (O-GlcNAcylation) in primary astrocytes in vitro. Neurobehavioral tests, Nissl staining, CCK8 assay, and flow cytometry for apoptosis were used to assess neuronal function. Immunofluorescence staining was used to detect astrocyte reactivity and the intracellular distribution of STAT3. Immunoprecipitation combined with Western blotting was used to evaluate the O-GlcNAcylation of STAT3. Protein expression and phosphorylation levels were detected by Western blotting. ELISA was conducted to detect the detrimental cytokines IL-6 and IL-1β in astrocyte-conditioned medium. Sevoflurane postconditioning enhanced the O-GlcNAcylation of astrocytic STAT3 following HI insult via the manner of OGT. Crosstalk between O-GlcNAcylation and phosphorylation of STAT3 showed that O-GlcNAcylation inhibited STAT3 phosphorylation. The inhibitory effect on astrocytes suppressed STAT3 nuclear translocation, reduced astrocyte reactivity, decreased the release of the inflammatory cytokines IL6 and IL-1β, attenuated neuronal apoptosis following HI insult, and improved neuron viability. Sevoflurane postconditioning increased astrocytic STAT3 O-GlcNAcylation level to competitively inhibit STAT3 phosphorylation. This deactivated downstream inflammation pathways and reduced astrocyte reactivity, thereby mitigating HI insult in neurons both in vivo and in vitro.

Protective Effect of Aloe-emodin on Cognitive Function in Copper-loaded Rats Based on The Inhibition of Hippocampal Neuron Ferroptosis

BACKGROUND

Aloe-emodin (AE), a monomer derived from traditional Chinese medicine, has demonstrated remarkable efficacy in the clinical management of cognitive disorders. Ferroptosis (FPT), a specialized form of programmed cell death, plays a critical role in the pathological progression of various cognitive diseases.

METHODS

This study explored the therapeutic potential of AE in a rat model of Wilson's disease cognitive impairments (WDCI) and examined whether these effects are mediated through the silencing information regulator 1 (SIRT1)-regulated FPT signaling pathway. Employing techniques, such as the Morris water maze (MWM), Hematoxylin & eosin (H&E) staining, Transmission electron microscopy (TEM), Immunofluorescence (IF), assessments of oxidative stress markers, and measurements of FPT-related protein levels, we evaluated the extent of SIRT1-mediated FPT and the therapeutic efficacy of AE.

RESULTS

The findings from the WD copper-loaded rat model experiments revealed that MWM, H&E, TEM, and IF outcomes indicated AE's potential to promote the restoration of learning and memory functions, ameliorate hippocampal neuronal morphological damage, and preserve cell membrane integrity. Results from western blot (WB) and ELISA analyses demonstrated that AE markedly upregulated the expression of SIRT1, nuclear factor erythroid-2-related factor 2 (Nrf2), solute carrier family 7 member 11 (SCL7A11), and glutathione peroxidase 4 (GPX4) proteins while simultaneously reversing the expression of oxidative stress markers such as malondialdehyde (MDA), glutathione (GSH), and superoxide dismutase (SOD), and reactive oxygen species (ROS). Consequently, we posit that AE may attenuate WD copper-loaded rat model hippocampal neuronal FPT by activating the SIRT1-mediated signaling pathway.

CONCLUSION

These findings suggested that AE mitigates WD copper-loaded rat model hippocampal neuronal damage through the activation of SIRT1-mediated FPT, thereby presenting a valuable candidate Chinese herbal monomer for the clinical treatment of WDCI.

Nrf2 mitigates sepsis-associated encephalopathy-induced hippocampus ferroptosis via modulating mitochondrial dynamic homeostasis

Sepsis-associated encephalopathy (SAE) is a serious neurological complication accompanied with acute and long-term cognitive dysfunction. Ferroptosis is a newly discovered type of cell death that is produced by iron-dependent lipid peroxidation. Emerging evidence suggests that ferroptosis is involved in SAE. The nuclear factor erythroid 2-related factor 2 (Nrf2) is a mitochondria related gene involved in ferroptosis. However, the role of Nrf2 in SAE and the mechanisms remains elusive. In this study, we found that Nrf2 knockout aggravated cognitive and emotional dysfunction and promoted caecal ligation and puncture (CLP)-induced brain injury and hippocampus ferroptosis as indicated by the increase of ROS, Fe2+ and the levels of proinflammatory cytokines. Meanwhile, the levels of glutathione peroxidase 4 (GPX4), SLC7A11 and glutathionewere downregulatedin Nrf2 knockout group. In vitro experiments showed that mitochondrial ROS, Fe2+ and the expression of Fis1 and Drp1 decreased, and the level of Mfn1 and Opa-1 increased after Nrf2 overexpression. The silence of Nrf2 increased the expression of ROS, MDA and Fe2+, while decreased glutathione, mitochondrial membrane potential (MMP) and cell viability in vitro, indicating Nrf2 improved LPS-induced mitochondrial dysfunction and mitigated hippocampal cells ferroptosis. These results suggest that Nrf2 could inhibit ferroptosis and neuroinflammation in hippocampus and reduce cognitive dysfunction in SAE mice, making it a potential therapeutic target in the treatment of SAE. The protective effects of Nrf2 on the brain may be mediated by maintaining mitochondrial dynamic homeostasis.

Role of the transcription factor NRF2 in maintaining the integrity of the Blood-Brain Barrier

BACKGROUND

The Blood-Brain Barrier (BBB) is a complex and dynamic interface that regulates the exchange of molecules and cells between the blood and the central nervous system. It undergoes structural and functional throughout oxidative stress and inflammation, which may compromise its integrity and contribute to the pathogenesis of neurodegenerative diseases.

MAIN BODY

Maintaining BBB integrity is of utmost importance in preventing a wide range of neurological disorders. NRF2 is the main transcription factor that regulates cellular redox balance and inflammation-related gene expression. It has also demonstrated a potential role in regulating tight junction integrity and contributing to the inhibition of ECM remodeling, by reducing the expression of several metalloprotease family members involved in maintaining BBB function. Overall, we review current insights on the role of NRF2 in addressing protection against the effects of BBB dysfunction, discuss its involvement in BBB maintenance in different neuropathological diseases, as well as, some of its potential activators that have been used in vitro and in vivo animal models for preventing barrier dysfunction.

CONCLUSIONS

Thus, emerging evidence suggests that upregulation of NRF2 and its target genes could suppress oxidative stress, and neuroinflammation, restore BBB integrity, and increase its protection.

The interplay between ferroptosis and inflammation: therapeutic implications for cerebral ischemia-reperfusion

Stroke ranks as the second most significant contributor to mortality worldwide and is a major factor in disability. Ischemic strokes account for 71% of all stroke incidences globally. The foremost approach to treating ischemic stroke prioritizes quick reperfusion, involving methods such as intravenous thrombolysis and endovascular thrombectomy. These techniques can reduce disability but necessitate immediate intervention. After cerebral ischemia, inflammation rapidly arises in the vascular system, producing pro-inflammatory signals that activate immune cells, which in turn worsen neuronal injury. Following reperfusion, an overload of intracellular iron triggers the Fenton reaction, resulting in an excess of free radicals that cause lipid peroxidation and damage to cellular membranes, ultimately leading to ferroptosis. The relationship between inflammation and ferroptosis is increasingly recognized as vital in the process of cerebral ischemia-reperfusion (I/R). Inflammatory processes disturb iron balance and encourage lipid peroxidation (LPO) through neuroglial cells, while also reducing the activity of antioxidant systems, contributing to ferroptosis. Furthermore, the lipid peroxidation products generated during ferroptosis, along with damage-associated molecular patterns (DAMPs) released from ruptured cell membranes, can incite inflammation. Given the complex relationship between ferroptosis and inflammation, investigating their interaction in brain I/R is crucial for understanding disease development and creating innovative therapeutic options. Consequently, this article will provide a comprehensive introduction of the mechanisms linking ferroptosis and neuroinflammation, as well as evaluate potential treatment modalities, with the goal of presenting various insights for alleviating brain I/R injury and exploring new therapeutic avenues.

Sappanone a alleviates osteoarthritis progression by inhibiting chondrocyte ferroptosis via activating the SIRT1/Nrf2 signaling pathway

Osteoarthritis (OA) is a common degenerative joint disease that cause pain and disability in adults. Chondrocyte ferroptosis is found to be involved in OA progression. Sappanone A has been found as an anti-inflammatory and antioxidative agent in several diseases. This study aims to investigate the effects of sappanone A on OA progression and chondrocyte ferroptosis. IL-1β-induced chondrocytes and destabilization of the medial meniscus (DMM)-induced rats were respectively used as the OA model in vitro and in vivo. The effects of sappanone A on inflammation, extracellular matrix (ECM) metabolism, and ferroptosis were determined. Our results showed that in IL-1β-induced chondrocytes, sappanone A suppressed the production of NO, PGE2, TNF-α, IL-6, iNOS, and COX2. Sappanone A also inhibited the expression of MMP3, MMP13, and ADAMTS5, while increasing collagen II expression. Moreover, sappanone A alleviated cytotoxicity and decreased the levels of intracellular ROS, lipid ROS, MDA, and iron, while increasing GSH levels. Additionally, sappanone A increased the protein expression of SLC7A11 and GPX4. Administration of ferroptosis activator reversed the inhibitory effects of sappanone A on IL-1β-induced inflammation and ECM degradation. More importantly, Sappanone A activated the Nrf2 signaling by targeting SIRT1. The inhibition of sappanone A on ferroptosis was greatly eliminated due to the addition of SIRT1 inhibitor. Furthermore, intra-articular injection of sappanone A mitigated cartilage destruction and ferroptosis in DMM-induced OA rats. In conclusion, sappanone A protects against inflammation and ECM degradation in OA via decreasing chondrocyte ferroptosis by activating the SIRT1/Nrf2 signaling. These findings deepen our understanding of chondrocyte ferroptosis in OA and highlight the therapeutic potential of sappanone A for OA.

Nuclear factor erythroid 2-related factor-mediated signaling alleviates ferroptosis during cerebral ischemia-reperfusion injury

Cardiac arrest (CA) is a significant challenge for emergency physicians worldwide and leads to increased morbidity and mortality rates. The poor prognosis of CA primarily stems from the complexity and irreversibility of cerebral ischemia-reperfusion injury (CIRI). Ferroptosis, a form of programmed cell death characterized by iron overload and lipid peroxidation, plays a crucial role in the progression and treatment of CIRI. In this review, we highlight the mechanisms of ferroptosis within the context of CIRI, focusing on its role as a key contributor to neuronal damage and dysfunction post-CA. We explore the crucial involvement of the nuclear factor erythroid 2-related factor (Nrf2)-mediated signaling pathway in modulating ferroptosis-associated processes during CIRI. Through comprehensive analysis of the regulatory role of Nrf2 in the cellular responses to oxidative stress, we highlight its potential as a therapeutic target for mitigating ferroptotic cell death and improving the neurological prognosis of patients experiencing CA. Furthermore, we discuss interventions targeting the Kelch-like ECH-associated protein 1/Nrf2/antioxidant response element pathway, including the use of traditional Chinese medicine and Western medicine, which demonstrate potential for attenuating ferroptosis and preserving neuronal function in CIRI. Owing to the limitations in the safety, specificity, and effectiveness of Nrf2-targeted drugs, as well as the technical difficulties and ethical constraints in obtaining the results related to the brain pathological examination of patients, most of the studies focusing on Nrf2-related regulation of ferroptosis in CIRI are still in the basic research stage. Overall, this review aims to provide a comprehensive understanding of the mechanisms underlying ferroptosis in CIRI, offering insights into novel therapeutics aimed at enhancing the clinical outcomes of patients with CA.

The role of metal ions in stroke: Current evidence and future perspectives

Metal ions play a pivotal role in maintaining optimal brain function within the human body. Nevertheless, the accumulation of these ions can result in irregularities that lead to brain damage and dysfunction. Disruptions of metal ion homeostasis can result in various pathologies, including inflammation, redox dysregulation, and blood-brain barrier disruption. While research on metal ions has chiefly focused on neurodegenerative diseases, little attention has been given to their involvement in the onset and progression of stroke. Recent studies have identified cuproptosis and confirmed ferroptosis as significant factors in stroke pathology, underscoring the importance of metal ions in stroke pathology, including abnormal ion transport, neurotoxicity, blood-brain barrier damage, and cell death. Additionally, it provides an overview of contemporary metal ion chelators and detection techniques, which may offer novel approaches to stroke treatment.

The role of glutathione peroxidase 4 in neuronal ferroptosis and its therapeutic potential in ischemic and hemorrhagic stroke

Ferroptosis is a type of cell death that depends on iron and is driven by lipid peroxidation, playing a crucial role in neuronal death during stroke. A central element in this process is the inactivation of glutathione peroxidase 4 (GPx4), an antioxidant enzyme that helps maintain redox balance by reducing lipid hydroperoxides. This review examines the critical function of GPx4 in controlling neuronal ferroptosis following ischemic and hemorrhagic stroke. We explore the mechanisms through which GPx4 becomes inactivated in various stroke subtypes. In strokes, excess glutamate depletes glutathione (GSH) and products of hemoglobin breakdown overwhelm GPx4. Studies using genetic models with GPx4 deficiency underscore its vital role in maintaining neuronal survival and function. We also consider new therapeutic approaches to enhance GPx4 activity, including novel small molecule activators, adjustments in GSH metabolism, and selenium supplementation. Additionally, we outline the potential benefits of combining these GPx4-focused strategies with other anti-ferroptotic methods like iron chelation and lipoxygenase inhibition for enhanced neuroprotection. Furthermore, we highlight the significance of understanding the timing of GPx4 inactivation during stroke progression to design effective therapeutic interventions.

Quercetin inhibits ferroptosis through the SIRT1/Nrf2/HO-1 signaling pathway and alleviates asthma disease

Background

Quercetin (QCT) is a bioflavonoid derived from vegetables and fruits that has anti-inflammatory and anti-ferroptosis effects against various diseases. Previous studies have shown that QCT modulates the production of cellular inflammatory factors in asthma models and delays the development of chronic airway inflammation. However, the regulatory mechanism of QCT, a traditional Chinese medicine, in the treatment of asthma has not been elucidated. The aim of the present study is to investigate whether QCT can inhibit ferroptosis via the SIRT1/Nrf2 pathway and play a therapeutic role in asthma.

Methods

An ovalbumin-induced mouse asthma model was established, and its function was verified by hematoxylin eosin staining, enzyme linked immunosorbent assay, ferric ion assay, malondialdehyde and superoxide dismutase assays, dihydroethidium staining, immunohistochemical staining, western blotting, and quantitative real-time polymerase chain reaction.

Results

Our results indicated that an ovalbumin-induced asthma mouse model had been successfully established and that QCT inhibited inflammation, reduced serum levels of inflammatory factors IL-4, IL-5 and IL-13, increased superoxide dismutase levels in lung tissue homogenates, and reduced malondialdehyde and ferric ion production in asthmatic mice. In addition, we found that QCT was able to reverse the expression of SIRT1, Nrf2 and HO-1 in an in vivo asthma mouse model.

Conclusions

The data from this study indicate that QCT can alleviate asthma, and its mechanism is related to the regulation of ferroptosis, oxidative stress, and the expression of SIRT1 protein.

Histone modifications in hypoxic ischemic encephalopathy: Implications for therapeutic interventions

Hypoxic-ischemic encephalopathy (HIE) is a brain injury induced by many causes of cerebral tissue ischemia and hypoxia. Although HIE may occur at many ages, its impact on the neonatal brain is greater because it occurs during the formative stage. Recent research suggests that histone modifications may occur in the human brain in response to acute stress events, resulting in transcriptional changes and HIE development. Because there are no safe and effective therapies for HIE, researchers have focused on HIE treatments that target histone modifications. In this review, four main histone modifications are explored, histone methylation, acetylation, phosphorylation, and crotonylation, as well as their relevance to HIE. The efficacy of histone deacetylase inhibitors in the treatment of HIE is also explored. In conclusion, targeting histone modifications may be a novel strategy for elucidating the mechanism of HIE, as well as a novel approach to HIE treatment.

Comprehensive review of perioperative factors influencing ferroptosis

The perioperative period encompasses all phases of patient care from the decision to perform surgery until full recovery. Ferroptosis, a newly identified type of regulated cell death, influences a wide array of diseases, including those affecting the prognosis and regression of surgical patients, such as ischemia-reperfusion injury and perioperative cognitive dysfunction. This review systematically examines perioperative factors impacting ferroptosis such as surgical trauma-induced stress, tissue hypoxia, anesthetics, hypothermia, and blood transfusion. By analyzing their intrinsic relationships, we aim to improve intraoperative management, enhance perioperative safety, prevent complications, and support high-quality postoperative recovery, ultimately improving patient outcomes.

Therapeutic potential of resveratrol through ferroptosis modulation: insights and future directions in disease therapeutics

Resveratrol, a naturally occurring polyphenolic compound, has captivated the scientific community with its promising therapeutic potential across a spectrum of diseases. This review explores the complex role of resveratrol in modulating ferroptosis, a newly identified form of programmed cell death, and its potential implications for managing cardiovascular and cerebrovascular disorders, cancer, and other conditions. Ferroptosis is intricately linked to the pathogenesis of diverse diseases, with resveratrol exerting multifaceted effects on this process. It mitigates ferroptosis by modulating lipid peroxidation, iron accumulation, and engaging with specific cellular receptors, thereby manifesting profound therapeutic benefits in cardiovascular and cerebrovascular conditions, as well as oncological settings. Moreover, resveratrol's capacity to either suppress or induce ferroptosis through the modulation of signaling pathways, including Sirt1 and Nrf2, unveils novel therapeutic avenues. Despite resveratrol's limited bioavailability, advancements in molecular modification and drug delivery optimization have amplified its clinical utility. Future investigations are poised to unravel the comprehensive mechanisms underpinning resveratrol's action and expand its therapeutic repertoire. We hope this review could furnish a detailed and novel insight into the exploration of resveratrol in the regulation of ferroptosis and its therapeutic prospects.

Overview of ferroptosis and pyroptosis in acute liver failure

In this editorial, we comment on the article by Zhou et al published in a recent issue. We specifically focus on the crucial roles of ferroptosis and pyroptosis in acute liver failure (ALF), a disease with high mortality rates. Ferroptosis is the result of increased intracellular reactive oxygen species due to iron accumulation, glutathione (GSH) depletion, and decreased GSH peroxidase 4 activity, while pyroptosis is a procedural cell death mediated by gasdermin D which initiates a sustained inflammatory process. In this review, we describe the characteristics of ferroptosis and pyroptosis, and discuss the involvement of the two cell death modes in the onset and development of ALF. Furthermore, we summarize several interfering methods from the perspective of ferroptosis and pyroptosis for the alleviation of ALF. These observations might provide new targets and a theoretical basis for the treatment of ALF, which are also crucial for improving the prognosis of patients with ALF.

β-1,4-Galactosyltransferase 1 protects against cerebral ischemia injury in mice by suppressing ferroptosis via the TAZ/Nrf2/HO-1 signaling pathway

BACKGROUND

Ischemic stroke leads a primary cause of mortality in human diseases, with a high disability rate worldwide. This study aims to investigate the function of β-1,4-galactosyltransferase 1 (B4galt1) in mouse brain ischemia/reperfusion (I/R) injury.

METHODS

Recombinant human B4galt1 (rh-B4galt1) was intranasally administered to the mice model of middle cerebral artery occlusion (MCAO)/reperfusion. In this study, the impact of rh-B4galt1 on cerebral injury assessed using multiple methods, including the neurological disability status scale, 2,3,5-triphenyltetrazolium chloride (TTC), Nissl and TUNEL staining. This study utilized laser speckle Doppler flowmeter to monitor the cerebral blood flow. Western blotting was performed to assess the protein expression levels, and fluorescence-labeled dihydroethidium method was performed to determine the superoxide anion generation. Assay kits were used for the measurement of iron, malondialdehyde (MDA) and glutathione (GSH) levels.

RESULTS

We demonstrated that rh-B4galt1 markedly improved neurological function, reduced cerebral infarct volume and preserved the completeness of blood-brain barrier (BBB) for preventing damage. These findings further illustrated that rh-B4galt1 alleviated oxidative stress, lipid peroxidation, as well as iron deposition induced by I/R. The vital role of ferroptosis was proved in brain injury. Furthermore, the rh-B4galt1 could increase the levels of TAZ, Nrf2 and HO-1 after I/R. And TAZ-siRNA and ML385 reversed the neuroprotective effects of rh-B4galt1.

CONCLUSIONS

The results indicated that rh-B4galt1 implements neuroprotective effects by modulating ferroptosis, primarily via upregulating TAZ/Nrf2/HO-1 pathway. Thus, B4galt1 could be seen as a promising novel objective for ischemic stroke therapy.

Avicularin Attenuated Lead-Induced Ferroptosis, Neuroinflammation, and Memory Impairment in Mice

Lead (Pb) is a common environmental neurotoxicant that results in abnormal neurobehavior and impaired memory. Avicularin (AVL), the main dietary flavonoid found in several plants and fruits, exhibits neuroprotective and hepatoprotective properties. In the present study, the effects of AVL on Pb-induced neurotoxicity were evaluated using ICR mice to investigate the molecular mechanisms behind its protective effects. Our study has demonstrated that AVL treatment significantly ameliorated memory impairment induced by lead (Pb). Furthermore, AVL mitigated Pb-triggered neuroinflammation, ferroptosis, and oxidative stress. The inhibition of Pb-induced oxidative stress in the brain by AVL was evidenced by the reduction in malondialdehyde (MDA) levels and the enhancement of glutathione (GSH) and glutathione peroxidase (GPx) activities. Additionally, in the context of lead-induced neurotoxicity, AVL mitigated ferroptosis by increasing the expression of GPX4 and reducing ferrous iron levels (Fe2+). AVL increased the activities of glycogenolysis rate-limiting enzymes HK, PK, and PYG. Additionally, AVL downregulated TNF-α and IL-1β expression while concurrently enhancing the activations of AMPK, Nrf2, HO-1, NQO1, PSD-95, SNAP-25, CaMKII, and CREB in the brains of mice. The findings from this study suggest that AVL mitigates the memory impairment induced by Pb, which is associated with the AMPK/Nrf2 pathway and ferroptosis.

Isochlorogenic acid A ameliorated lead-induced anxiety-like behaviors in mice by inhibiting ferroptosis-mediated neuroinflammation via the BDNF/Nrf2/GPX4 pathways

Lead (Pb) is a common environmental neurotoxicant that causes behavioral impairments in both rodents and humans. Isochlorogenic acid A (ICAA), a phenolic acid found in a variety of natural sources such as tea, fruits, vegetables, coffee, plant-based food products, and various medicinal plants, exerts multiple effects, including protective effects on the lungs, livers, and intestines. The objective of this study was to investigate the potential neuroprotective effects of ICAA against Pb-induced neurotoxicity in ICR mice. The results indicate that ICAA attenuates Pb-induced anxiety-like behaviors. ICAA reduced neuroinflammation, ferroptosis, and oxidative stress caused by Pb. ICAA successfully mitigated the Pb-induced deficits in the cholinergic system in the brain through the reduction of ACH levels and the enhancement of AChE and BChE activities. ICAA significantly reduced the levels of ferrous iron and MDA in the brain and prevented decreases in GSH, SOD, and GPx activity. Immunofluorescence analysis demonstrated that ICAA attenuated ferroptosis and upregulated GPx4 expression in the context of Pb-induced nerve damage. Additionally, ICAA downregulated TNF-α and IL-6 expression while concurrently enhancing the activations of Nrf2, HO-1, NQO1, BDNF, and CREB in the brains of mice. The inhibition of BDNF, Nrf2 and GPx4 reversed the protective effects of ICAA on Pb-induced ferroptosis in nerve cells. In general, ICAA ameliorates Pb-induced neuroinflammation, ferroptosis, oxidative stress, and anxiety-like behaviors through the activation of the BDNF/Nrf2/GPx4 pathways.

Advancements in understanding the role of ferroptosis in hypoxia-associated brain injury: a narrative review

Background and Objective

Ferroptosis, a form of programmed cell death driven by lipid peroxidation and dependent on iron ions, unfolds through a sophisticated interplay of multiple biological processes. These include perturbations in iron metabolism, lipid peroxidation, aberrant amino acid metabolism, disruptions in hypoxia-inducible factor-prolyl hydroxylase (HIF-PHD) axis, and endoplasmic reticulum (ER) stress. Recent studies indicate that ferroptosis may serve as a promising therapeutic target for hypoxia-associated brain injury such as hypoxic-ischemic brain damage (HIBD) and cerebral ischemia-reperfusion injury (CIRI). HIBD is a neonatal disease that can be fatal, causing death or mental retardation in newborns. HIBD is a kind of diffuse brain injury, which is characterized by apoptosis of nerve cells and abnormal function and structure of neurons after cerebral hypoxia and ischemia. At present, there are no fundamental prevention and treatment measures for HIBD. The brain is the most sensitive organ of the human body to hypoxia. Cerebral ischemia will lead to the damage of local brain tissue and its function, and CIRI will lead to a series of serious consequences. We hope to clarify the mechanism of ferroptosis in hypoxia-associated brain injury, inhibit the relevant targets of ferroptosis in hypoxia-associated brain injury to guide clinical treatment, and provide guidance for the subsequent treatment of disease-related drugs.

Methods

Our research incorporated data on "ferroptosis", "neonatal hypoxic ischemia", "hypoxic ischemic brain injury", "hypoxic ischemic encephalopathy", "brain ischemia-reperfusion injury", and "therapeutics", which were sourced from Web of Science, PubMed, and comprehensive reviews and articles written in English.

Key Content and Findings

This review delineates the underlying mechanisms of ferroptosis and the significance of these pathways in hypoxia-associated brain injury, offering an overview of therapeutic strategies for mitigating ferroptosis.

Conclusions

Ferroptosis involves dysregulation of iron metabolism, lipid peroxidation, amino acid metabolism, dysregulation of HIF-PHD axis and endoplasmic reticulum stress (ERS). By reviewing the literature, we identified the involvement of the above processes in HIBD and CIRI, and summarized a series of therapeutic measures for HIBD and CIRI by inhibiting ferroptosis. We hope this study would provide guidance for the clinical treatment of HIBD and CIRI in the future.

miR-30a-5p mediates ferroptosis of hippocampal neurons in chronic cerebral hypoperfusion-induced cognitive dysfunction by modulating the SIRT1/NRF2 pathway

OBJECTIVE

Chronic cerebral hypoperfusion (CCH) is a common cause of brain dysfunction. As a microRNA (also known as miRNAs or miRs), miR-30a-5p participates in neuronal damage and relates to ferroptosis. We explored the in vivo and in vitro effects and functional mechanism of miR-30a-5p in CCH-triggered cognitive impairment through the silent information regulator 1 (SIRT1)/nuclear factor erythroid 2-related factor 2 (NRF2) pathway.

METHODS

After 1 month of CCH modeling through bilateral common carotid artery stenosis, mice were injected with 2 μL antagomir (also known as anti-miRNAs) miR-30a-5p, with cognitive function evaluated by Morris water maze and novel object recognition tests. In vitro HT-22 cell oxygen glucose deprivation (OGD) model was established, followed by miR-30a-5p inhibitor and/or si-SIRT1 transfections, with Fe2+ concentration, malonaldehyde (MDA) and glutathione (GSH) contents, reactive oxygen species (ROS), miR-30a-5p and SIRT1 and glutathione peroxidase 4 (GPX4) protein levels, NRF2 nuclear translocation, and miR-30a-5p-SIRT1 targeting relationship assessed.

RESULTS

CCH-induced mice showed obvious cognitive impairment, up-regulated miR-30a-5p, and down-regulated SIRT1. Ferroptosis occurred in hippocampal neurons, manifested by elevated Fe2+ concentration and ROS and MDA levels, mitochondrial atrophy, and diminished GSH content. Antagomir miR-30a-5p or miR-30a-5p inhibitor promoted SIRT1 expression and NRF2 nuclear translocation, increased GPX4, cell viability and GSH content, and reduced Fe2+ concentration and ROS and MDA levels. miR-30a-5p negatively regulated SIRT1. In vitro, miR-30a-5p knockout increased NRF2 nuclear translocation by up-regulating SIRT1, inhibiting OGD-induced ferroptosis in HT-22 cells.

CONCLUSION

miR-30a-5p induces hippocampal neuronal ferroptosis and exacerbates post-CCH cognitive dysfunction by targeting SIRT1 and reducing NRF2 nuclear translocation.

Regulated cell death in hypoxic-ischaemic encephalopathy: recent development and mechanistic overview

Hypoxic-ischaemic encephalopathy (HIE) in termed infants remains a significant cause of morbidity and mortality worldwide despite the introduction of therapeutic hypothermia. Depending on the cell type, cellular context, metabolic predisposition and insult severity, cell death in the injured immature brain can be highly heterogenous. A continuum of cell death exists in the H/I-injured immature brain. Aside from apoptosis, emerging evidence supports the pathological activation of necroptosis, pyroptosis and ferroptosis as alternative regulated cell death (RCD) in HIE to trigger neuroinflammation and metabolic disturbances in addition to cell loss. Upregulation of autophagy and mitophagy in HIE represents an intrinsic neuroprotective strategy. Molecular crosstalk between RCD pathways implies one RCD mechanism may compensate for the loss of function of another. Moreover, mitochondrion was identified as the signalling "hub" where different RCD pathways converge. The highly-orchestrated nature of RCD makes them promising therapeutic targets. Better understanding of RCD mechanisms and crosstalk between RCD subtypes likely shed light on novel therapy development for HIE. The identification of a potential RCD converging node may open up the opportunity for simultaneous and synergistic inhibition of cell death in the immature brain.

RBM3 Ameliorates Acute Brain Injury-induced Inflammation and Oxidative Stress by Stabilizing GAS6 mRNA Through Nrf2 Signaling Pathway

RNA-binding motif protein 3 (RBM3), as a cold-inducible protein, exhibits neuroprotective function in brain disorders. This study was conducted to investigate the effects of RBM3 on acute brain injury (ABI) and its underlying mechanism. The cerebral injury (CI) rat model and oxygen-glucose deprivation (OGD) cell model were established. The neurological severity score, wire-grip score, morris water maze test, and Y-maze test were used to detect the neurological damage, vestibular motor, learning, and memory functions. Cerebral injury, apoptosis, oxidative stress, and inflammatory level were evaluated by hematoxylin-eosin and TUNEL staining and specific kits. Flow cytometry was used to analyze the apoptosis rate. The relationship between RBM3 and growth arrest specific (GAS) 6 was analyzed by RNA immunoprecipitation assay. The results indicated that RBM3 recovered of neurological function and behaviour impairment of CI rats. Additionally, RBM3 reversed the increased oxidative stress, inflammatory level, and apoptosis induced by CI and OGD. RBM3 interacted with GAS6 to activate the Nrf2 signaling pathway, thus playing neuroprotection on ABI. Besides, the results of RBM3 treatment were similar to those of mild hypothermia treatment. In summary, RBM3 exerted neuroprotection and ameliorated inflammatory levels and oxidative stress by stabilizing GAS6 mRNA through the Nrf2 signaling pathway, suggesting that RBM3 might be a potential therapeutic candidate for treating ABI.

Resveratrol protects against diabetic retinal ganglion cell damage by activating the Nrf2 signaling pathway

Objective

Oxidative stress-induced retinal neurodegenerative changes are among the pathological alterations observed in diabetic retinopathy. Resveratrol (RSV), a polyphenolic compound with diverse pharmacological effects, has shown preventive qualities in several neurodegenerative illnesses, including anti-inflammatory, anti-aging, and antioxidant benefits. However, its therapeutic efficacy in diabetic retinal neurodegeneration has not yet been thoroughly elucidated. Our study aimed to explore the protective mechanisms and therapeutic benefits of RSV on diabetic retinal neurodegeneration alterations.

Materials and methods

Using streptozotocin, we created a diabetic mouse model and conducted visual electrophysiological examinations on mice from the normal group, diabetic group, and diabetic group treated with RSV. Retinas were harvested for histological staining. Additionally, primary retinal ganglion cells cultured in high glucose conditions were used to assess malondialdehyde (MDA) levels and superoxide dismutase (SOD) levels upon siRNA-mediated nuclear factor erythroid 2-related factor 2 (Nrf2) interference. Protein levels of Nrf-2, heme oxygenase-1 (HO-1), and transcriptional levels of them were also measured.

Results

We demonstrated that RSV significantly improved the retinal morphology and function in the diabetic retinopathy model mice. The treated mice exhibited notable improvements in visual electrophysiology, with a significant reduction in retinal ganglion cell apoptosis. Following RSV treatment, the high glucose-cultured ganglion cells demonstrated a considerable rise in SOD levels and a substantial drop in MOD. Moreover, the protein expression of solute carrier family 7 member 11 (SLC7A11) and Nrf2 significantly increased. RT-PCR and Western blot results indicated a significant attenuation of RSV's therapeutic effects upon Nrf2 inhibition.

Conclusion

Our findings suggest that RSV may reduce oxidative stress levels in the retina and inhibit retinal ganglion cell apoptosis via reducing the Nrf2/HO-1 pathway, which lessens the harm that excessive glucose causes to the retina.

The anti-atherosclerotic effect of Paeonol against the lipid accumulation in macrophage-derived foam cells by inhibiting ferroptosis via the SIRT1/NRF2/GPX4 signaling pathway

Atherosclerosis (AS) is the underlying cause of many severe vascular diseases and is primarily characterized by abnormal lipid metabolism. Paeonol (Pae), a bioactive compound derived from Paeonia Suffruticosa Andr., is recognized for its significant role in reducing lipid accumulation. Our research objective is to explore the link between lipid buildup in foam cells originating from macrophages and the process of ferroptosis, and explore the effect and mechanism of Pae on inhibiting AS by regulating ferroptosis. In our animal model, ApoE-deficient mice, which were provided with a high-fat regimen to provoke atherosclerosis, were administered Pae. The treatment was benchmarked against simvastatin and ferrostatin-1. The results showed that Pae significantly reduced aortic ferroptosis and lipid accumulation in the mice. In vitro experiments further demonstrated that Pae could decrease lipid accumulation in foam cells induced by oxidized low-density lipoprotein (LDL) and challenged with the ferroptosis inducer erastin. Crucially, the protective effect of Pae against lipid accumulation was dependent on the SIRT1/NRF2/GPX4 pathway, as SIRT1 knockdown abolished this effect. Our findings suggest that Pae may offer a novel therapeutic approach for AS by inhibiting lipid accumulation through the suppression of ferroptosis, mediated by the SIRT1/NRF2/GPX4 pathway. Such knowledge has the potential to inform the creation of novel therapeutic strategies aimed at regulating ferroptosis within the context of atherosclerosis.

Emerging ferroptosis inhibitors as a novel therapeutic strategy for the treatment of neonatal hypoxic-ischemic encephalopathy

Neonatal hypoxia-ischemia encephalopathy (NHIE), an oxygen deprivation-mediated brain injury due to birth asphyxia or reduced cerebral blood perfusion, often leads to lifelong sequelae, including seizures, cerebral palsy, and mental retardation. NHIE poses a significant health challenge, as one of the leading causes of neonatal morbidity and mortality globally. Despite this, available therapies are limited. Numerous studies have recently demonstrated that ferroptosis, an iron-dependent non-apoptotic regulated form of cell death characterized by lipid peroxidation (LPO) and iron dyshomeostasis, plays a role in the genesis of NHIE. Moreover, recently discovered compounds have been shown to exert potential therapeutic effects on NHIE by inhibiting ferroptosis. This comprehensive review summarizes the fundamental mechanisms of ferroptosis contributing to NHIE. We focus on various emerging therapeutic compounds exhibiting characteristics of ferroptosis inhibition and delineate their pharmacological benefits for the treatment of NHIE. This review suggests that pharmacological inhibition of ferroptosis may be a potential therapeutic strategy for NHIE.

A New Perspective in the Treatment of Ischemic Stroke: Ferroptosis

Ischemic stroke is a common neurological disease. Currently, there are no Food and Drug Administration-approved drugs that can maximize the improvement in ischemic stroke-induced nerve damage. Hence, treating ischemic stroke remains a clinical challenge. Ferroptosis has been increasingly studied in recent years, and it is closely related to the pathophysiological process of ischemic stroke. Iron overload, reactive oxygen species accumulation, lipid peroxidation, and glutamate accumulation associated with ferroptosis are all present in ischemic stroke. This article focuses on describing the relationship between ferroptosis and ischemic stroke and summarizes the relevant substances that ameliorate ischemic stroke-induced neurological damage by inhibiting ferroptosis. Finally, the problems in the treatment of ischemic stroke targeting ferroptosis are discussed, hoping to provide a new direction for its treatment.

The Interplay between Ferroptosis and Neuroinflammation in Central Neurological Disorders

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

Attenuation of neuronal ferroptosis in intracerebral hemorrhage by inhibiting HDAC1/2: Microglial heterogenization via the Nrf2/HO1 pathway

AIM

The class I histone deacetylases (HDACs) implicate in microglial heterogenization and neuroinflammation following Intracerebral hemorrhage (ICH). Ferroptosis has also been reported in the ICH model. However, the relationship between HDAC1/2's role in microglial heterogenization and neuronal ferroptosis remains unclear.

METHODS

In both in vivo and in vitro models of ICH, we used Romidepsin (FK228), a selective HDAC1/2 inhibitor, to investigate its effects on microglial heterogenization and neuronal ferroptosis. In the in vitro ICH model using Hemin, a transwell system was utilized to examine how microglia-driven inflammation and ICH-triggered neuronal ferroptosis interact. Immunostaining, Western blotting and RT-qPCR were used to evaluate the microglial heterogenization and neuronal ferroptosis. Microglial heterogenization, neuronal ferroptosis, and neurological dysfunctions were assessed in vivo ICH mice model performed by autologous blood injection.

RESULTS

HDAC1/2 inhibition altered microglial heterogenization after ICH, as showing the reducing neuroinflammation and shifting microglia towards an anti-inflammatory phenotype by immunostaining and qPCR results. HDAC1/2 inhibition reduced ferroptosis, characterized by high ROS and low GPx4 expression in HT22 cells, and reduced iron and lipid deposition post-ICH in vivo. Additionally, the Nrf2/HO1 signaling pathway, especially acetyl-Nrf2, activated in the in vivo ICH model due to HDAC1/2 inhibition, plays a role in regulating microglial heterogenization. Furthermore, HDAC1/2 inhibition improved sensorimotor and histological outcomes post-ICH, offering a potential mechanism against ICH.

CONCLUSION

Inhibition of HDAC1/2 reduces neuro-ferroptosis by modifying the heterogeneity of microglia via the Nrf2/HO1 pathway, with a particular focus on acetyl-Nrf2. Additionally, this inhibition aids in the faster removal of hematomas and lessens prolonged neurological impairments, indicating novel approach for treating ICH.

The cell-specific roles of Nrf2 in acute and chronic phases of ischemic stroke

Ischemic stroke refers to the sudden loss of blood flow in a specific area of the brain. It is the fifth leading cause of mortality and the leading cause of permanent disability. The transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) controls the production of several antioxidants and protective proteins and it has been investigated as a possible pharmaceutical target for reducing harmful oxidative events in brain ischemia. Each cell type exhibits different roles and behaviors in different phases post-stroke, which is comprehensive yet important to understand to optimize management strategies and goals for care for stroke patients. In this review, we comprehensively summarize the protective effects of Nrf2 in experimental ischemic stroke, emphasizing the role of Nrf2 in different cell types including neurons, astrocytes, oligodendrocytes, microglia, and endothelial cells during acute and chronic phases of stroke and providing insights on the neuroprotective role of Nrf2 on each cell type throughout the long term of stroke care. We also highlight the importance of targeting Nrf2 in clinical settings while considering a variety of important factors such as age, drug dosage, delivery route, and time of administration.

Pterostilbene attenuates heart failure by inhibiting myocardial ferroptosis through SIRT1/GSK-3β/GPX4 signaling pathway

Sustained myocardial injury due to hypertension and diabetes mellitus leads to production of endogenous reactive oxygen species (ROS) and insufficient myocardial antioxidant capacity, increasing the risk of cardiomyocyte ferroptosis. Ferroptosis is a nonapoptotic form of cell death driven by unrestricted lipid peroxidation. Dysfunction of the glutathione peroxidase 4 (GPX4) antioxidant system also plays an important role in ferroptosis. Cardiomyocyte ferroptosis ultimately leads to myocardial deterioration, such as inflammation, fibrosis, and cardiac remodeling, resulting in structural and functional changes. Pterostilbene (PTS), a demethylated derivative of resveratrol, exhibits strong anti-inflammatory and antioxidative activities. In this study, we used in vitro experiments to explore ferroptosis induced by angiotensin II (Ang II) of primary cardiac myocytes (CMs) and in vivo experiments to prepare a transverse aortic constriction (TAC)-induced cardiac dysfunction mouse model. PTS can significantly ameliorate Ang II-induced cardiomyocyte ferroptosis in vitro and reduce cardiac remodeling, while improving cardiac function in mice after TAC in vivo. Further mechanistic investigations revealed that PTS exerts its protective effect through the SIRT1/GSK-3β/GPX4 pathway. After siRNA-mediated knockdown of SIRT1 or GPX4 in CMs, the protective effects of PTS on cardiomyocytes were abolished. This study provides important theoretical support for the potential of PTS to attenuate pathological cardiac remodeling and heart failure and provides a preliminary exploration of the molecular pathways involved in its protective mechanism.

SIRT1 activated by AROS sensitizes glioma cells to ferroptosis via induction of NAD+ depletion-dependent activation of ATF3

Ferroptosis is a type of programmed cell death resulting from iron overload-dependent lipid peroxidation, and could be promoted by activating transcription factor 3 (ATF3). SIRT1 is an enzyme accounting for removing acetylated lysine residues from target proteins by consuming NAD+, but its role remains elusive in ferroptosis and activating ATF3. In this study, we found SIRT1 was activated during the process of RSL3-induced glioma cell ferroptosis. Moreover, the glioma cell death was aggravated by SIRT1 activator SRT2183, but suppressed by SIRT inhibitor EX527 or when SIRT1 was silenced with siRNA. These indicated SIRT1 sensitized glioma cells to ferroptosis. Furthermore, we found SIRT1 promoted RSL3-induced expressional upregulation and nuclear translocation of ATF3. Silence of ATF3 with siRNA attenuated RSL3-induced increases of ferrous iron and lipid peroxidation, downregulation of SLC7A11 and GPX4 and depletion of cysteine and GSH. Thus, SIRT1 promoted glioma cell ferroptosis by inducting ATF3 activation. Mechanistically, ATF3 activation was reinforced when RSL3-induced decline of NAD+ was aggravated by FK866 that could inhibit NAD + synthesis via salvage pathway, but suppressed when intracellular NAD+ was maintained at higher level by supplement of exogenous NAD+. Notably, the NAD + decline caused by RSL3 was enhanced when SIRT1 was further activated by SRT2183, but attenuated when SIRT1 activation was inhibited by EX527. These indicated SIRT1 promoted ATF3 activation via consumption of NAD+. Finally, we found RSL3 activated SIRT1 by inducing reactive oxygen species-dependent upregulation of AROS. Together, our study revealed SIRT1 activated by AROS sensitizes glioma cells to ferroptosis via activation of ATF3-dependent inhibition of SLC7A11 and GPX4.

Targeting ferroptosis and ferritinophagy: new targets for cardiovascular diseases

Cardiovascular diseases (CVDs) are a leading factor driving mortality worldwide. Iron, an essential trace mineral, is important in numerous biological processes, and its role in CVDs has raised broad discussion for decades. Iron-mediated cell death, namely ferroptosis, has attracted much attention due to its critical role in cardiomyocyte damage and CVDs. Furthermore, ferritinophagy is the upstream mechanism that induces ferroptosis, and is closely related to CVDs. This review aims to delineate the processes and mechanisms of ferroptosis and ferritinophagy, and the regulatory pathways and molecular targets involved in ferritinophagy, and to determine their roles in CVDs. Furthermore, we discuss the possibility of targeting ferritinophagy-induced ferroptosis modulators for treating CVDs. Collectively, this review offers some new insights into the pathology of CVDs and identifies possible therapeutic targets.

Menaquinone-4 attenuates ferroptosis by upregulating DHODH through activation of SIRT1 after subarachnoid hemorrhage

BACKGROUND

Menaquinone-4(MK-4), the isoform of vitamin K2 in the brain, exerts neuroprotective effects against a variety of central nervous system disorders. This study aimed to demonstrate the anti-ferroptosis effects of MK-4 in neurons after SAH.

METHODS

A subarachnoid hemorrhage (SAH) model was prepared by endovascular perforation in mice. In vitro hemoglobin stimulation of primary cortical neurons mimicked SAH. MK-4, Brequinar (BQR, DHODH inhibitor), and Selisistat (SEL, SIRT1 inhibitor) were administered, respectively. Subsequently, WB, immunofluorescence was used to determine protein expression and localization, and transmission electron microscopy was used to observe neuronal mitochondrial structure while other indicators of ferroptosis were measured.

RESULTS

MK-4 treatment significantly upregulated the protein levels of DHODH; decreased GSH, PTGS2, NOX1, ROS, and restored mitochondrial membrane potential. Meanwhile, MK-4 upregulated the expression of SIRT1 and promoted its entry into the nucleus. BQR or SEL partially abolished the protective effect of MK-4 on, neurologic function, and ferroptosis.

CONCLUSIONS

Taken together, our results suggest that MK-4 attenuates ferroptosis after SAH by upregulating DHODH through the activation of SIRT1.

FTO-Mediated m6A Modification of FTH1 Inhibits Ferroptosis of Neurons in Neonatal Cerebral Hypoxic Ischemia

FTO alpha-ketoglutarate dependent dioxygenase (FTO) is aberrantly expressed in brain disorders. However, the roles of FTO in neonatal hypoxic-ischemic brain injury (HIE) are still unclear. This study aims to investigate the potential of FTO in neonatal HIE. Oxygen-glucose deprivation (OGD) was used to establish HIE in vitro. mRNA levels were detected by real-time reverse transcriptase-quantitative polymerase chain reaction (RT-qPCR). Protein expression was detected by Western blot. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), ferrous iron (Fe2+) and glutathione (GSH) was detected by specific kit. m6A sites were analyzed using SRAMP and further verify by methylated RNA immunoprecipitation (MeRIP) assay. Cell proliferation was determined by Cell Counting Kit-8 (CCK-8) assay. Cell death was determined by propidium iodide (PI) staining. FTO was downregulated in patients with neonatal HIE and OGD-treated neurons. Moreover, FTO mRNA expression was decreased in ferroptosis inducer, especially ferric ammonium citrate (FAC). However, overexpression of FTO inhibited the ferroptosis of neurons. Moreover, FTO-mediated N6-methyladenosine (m6A) modification of ferritin heavy chain 1 (FTH1) suppressed its mRNA expression and stability, inhibiting its protein expression. However, overexpression of FTH1 abrogated the effects of FTO and promoted the ferroptosis of neurons. In summary, FTO functions as a protective role in neonatal HIE via inhibiting FTH1 signaling. Thence, targeting may be a promising strategy for FTO neonatal HIE.