Netrin-1 upregulates GPX4 and prevents ferroptosis after traumatic brain injury via the UNC5B/Nrf2 signaling pathway

Salvianolic acid B exerts cerebroprotective effects after traumatic brain injury via Nrf2-dependent antioxidant and anti-inflammatory cascades

BACKGROUND

Oxidative stress and inflammatory responses play crucial roles in the development of secondary brain injury following traumatic brain injury (TBI). Thus, this study aimed to investigate the potential cerebroprotective effects of salvianolic acid B (SalB) in mitigating oxidative stress and inflammatory responses post-TBI through the activation of Nrf2.

PURPOSE

This study aims to investigate the potential cerebroprotective effects of SalB in ameliorating oxidative stress and inflammatory responses following TBI by activating Nrf2, thereby laying a foundation for TBI treatment.

STUDY DESIGN

Controlled cortical impact and hydrogen peroxide were employed to replicate TBI in animal and cellular models, respectively.Behavioral studies predict neural function, Western Blot (WB) predicts oxidative stress, immunofluorescence and ELISA predict inflammatory response.The Nrf2 inhibitor ML385 was employed to investigate the involvement of the Nrf2 pathway in mediating the protective effects of SalB.

METHODS

SalB was delivered via intraperitoneal injection 1 h after TBI induction, with its neuroprotective efficacy evaluated across a range of concentrations. In the cellular assay, SalB was used to incubate cells simultaneously with H2O2. WB analysis was employed to quantify protein levels, while malondialdehyde, glutathione, superoxide intensity, and reactive oxygen radical probes were utilized to evaluate oxidative stress. Immunofluorescence and ELISA techniques were used to characterize microglia phenotype and inflammatory response. Behavioral assays were also conducted to evaluate neurological function. The Nrf2 inhibitor ML385 was employed to investigate the involvement of the Nrf2 pathway in mediating the protective effects of SalB.

RESULTS

Animal and cellular experiments indicate that SalB can mitigate oxidative stress through the Nrf2/Peroxiredoxin 2 pathway, and reduce inflammatory response via the Nrf2/Toll-like receptor 4/Myeloid differentiation primary response protein 88 pathway in a dose-dependent manner. Consequently, SalB demonstrates efficacy in enhancing neurological function following TBI. Conversely, the inhibitory effects of ML385 counteract the antioxidant and anti-inflammatory properties of SalB.

CONCLUSIONS

SalB exerts its beneficial effects post-TBI through Nrf2-dependent antioxidants and as anti-inflammatory responses.

Novel miRNAs, miR-937-3p, miR-4536-3p, and miR-4650-5p, can Modulate Neuronal Differentiation via the Wnt/MAPK Pathway in SH-SY5Y Cells

MicroRNAs (miRNAs) are small non-coding RNAs that regulate various biological processes, including cell differentiation. Despite their potential, their role in promoting neuronal differentiation by targeting neuronal genes and modulating signaling pathways is poorly understood. In this study, we aimed to elucidate the functions of miR-937-3p-, miR-4536-3p-, and miR-4650-5p-inhibitors in the neuronal differentiation of SH-SY5Y cells. We also aimed to determine the underlying mechanisms via qPCR, luciferase assay, immunocytochemistry, and western blotting analysis. Our findings confirmed that miRNAs participated in neuronal differentiation and regulated the Wnt/MAPK signaling pathway. Specifically, we identified Netrin1 (NTN1), Drebrin1 (DBN1), and Netrin-G1 (NTNG1) as target genes of miR-937-3p, miR-4536-3p, and miR-4650-5p, respectively. The treatment with the miRNA inhibitors increased the expression levels of neuronal markers such as TUBB3, NEFH, NEFM, NEFL, and MAP2. It also enhanced the protein expression levels of Wnt and MAPK signaling. Therefore, the inhibitors of miR-937-3p, miR-4536-3p, and miR-4650-5p could promote neuronal differentiation by targeting neuronal genes and activating the Wnt/MAPK signaling pathway.

Electroacupuncture improves cognitive function in high-fat diet/streptozocin-induced type 2 diabetic mice by inhibiting autophagy-related ferroptosis

At present, there lacks a definitive pharmaceutical intervention or therapeutic approach for diabetes-associated cognitive impairment. Herein, we delved into the impact of electroacupuncture on cognitive function in high-fat diet/streptozocin (HFD/STZ)-induced type 2 diabetes mellitus (T2DM) mice and underlying mechanisms. Hippocampal insulin resistance was determined by western blot analysis. Cognitive function was evaluated by Morris water maze test. The morphology of the hippocampal neurons was observed through hematoxylin & eosin staining and Nissl staining. Synaptic plasticity was assessed by western blot analysis. Immunofluorescence, immunohistochemistry, western blot and real-time PCR were employed to detect the levels of ferroptosis markers, autophagy markers, and netrin-1. Electroacupuncture treatment exhibited ameliorative outcomes on hippocampal insulin resistance, spatial learning, memory function, neuronal damage, and synaptic plasticity in T2DM mice. Furthermore, it effectively suppressed neuronal ferroptosis in the hippocampus by upregulating GPX4 and SLC7A11 expression, and reducing 4-HNE expression. Meanwhile, electroacupuncture intervention increased the levels of Beclin1 and LC3II/LC3I, as well as decreased the levels of p62 and phosphorylated-mTOR in the hippocampus of T2DM mice, suggesting that electroacupuncture facilitated autophagy activation by inhibiting mTOR activity. 3-MA-mediated autophagy inhibition undermined the beneficial effects of electroacupuncture on neuronal ferroptosis and cognitive deficits in T2DM mice. Additionally, the beneficial effects of electroacupuncture on autophagy and ferroptosis was achieved by upregulation of netrin-1 in the hippocampus. Our study revealed that electroacupuncture therapy inhibited neuronal ferroptosis via the activation of autophagy, thereby ameliorating cognitive deficits in T2DM mice.

Netrin-1 signaling pathway mechanisms in neurodegenerative diseases

Netrin-1 and its receptors play crucial roles in inducing axonal growth and neuronal migration during neuronal development. Their profound impacts then extend into adulthood to encompass the maintenance of neuronal survival and synaptic function. Increasing amounts of evidence highlight several key points: (1) Diminished Netrin-1 levels exacerbate pathological progression in animal models of Alzheimer's disease and Parkinson's disease, and potentially, similar alterations occur in humans. (2) Genetic mutations of Netrin-1 receptors increase an individuals' susceptibility to neurodegenerative disorders. (3) Therapeutic approaches targeting Netrin-1 and its receptors offer the benefits of enhancing memory and motor function. (4) Netrin-1 and its receptors show genetic and epigenetic alterations in a variety of cancers. These findings provide compelling evidence that Netrin-1 and its receptors are crucial targets in neurodegenerative diseases. Through a comprehensive review of Netrin-1 signaling pathways, our objective is to uncover potential therapeutic avenues for neurodegenerative disorders.

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.

Microglial Autophagic Dysregulation in Traumatic Brain Injury: Molecular Insights and Therapeutic Avenues

Traumatic brain injury (TBI) is a complex and multifaceted condition that can result in cognitive and behavioral impairments. One aspect of TBI that has received increasing attention in recent years is the role of microglia, the brain-resident immune cells, in the pathophysiology of the injury. Specifically, increasing evidence suggests that dysfunction in microglial autophagy, the process by which cells degrade and recycle their own damaged components, may contribute to the development and progression of TBI-related impairments. Here, we unravel the pathways by which microglia autophagic dysregulation predisposes the brain to secondary damage and neurological deficits following TBI. An overview of the role of autophagic dysregulation in perpetuation and worsening of the inflammatory response, neuroinflammation, and neuronal cell death in TBI follows. Further, we have evaluated several signaling pathways and processes that contribute to autophagy dysfunction-mediated inflammation, neurodegeneration, and poor outcome in TBI. Additionally, a discussion on the small molecule therapeutics employed to modulate these pathways and mechanisms to treat TBI have been presented. However, additional research is required to fully understand the processes behind these underlying pathways and uncover potential therapeutic targets for restoring microglial autophagic failure in TBI.

High-altitude hypoxia aggravated neurological deficits in mice induced by traumatic brain injury via BACH1 mediating astrocytic ferroptosis

Traumatic brain injury (TBI) is one of the leading causes of disability and mortality, which was classified as low-altitude TBI and high-altitude TBI. A large amount of literature shows that high-altitude TBI is associated with more severe neurological impairments and higher mortality rates compared to low-altitude TBI, due to the special environment of high-altitude hypoxia. However, the role of high-altitude hypoxia in the pathogenesis of TBI remains unclear. In order to deeply investigate this scientific issue, we constructed a high-altitude hypoxic TBI model at different altitudes and used animal behavioral assessments (Modified neurological severity score, rotarod test, elevated plus maze test) as well as histopathological analyses (brain gross specimens, brain water content, Evans blue content, hypoxia inducible factor-1α, Hematoxylin-Eosin staining and ROS detection) to reveal its underlying principles and characteristics. We found that with higher altitude, TBI-induced neurological deficits were more severe and the associated histopathological changes were more significant. Single-nuclear RNA sequencing was subsequently employed to further reveal differential gene expression profiles in high-altitude TBI. We found a significant increase in ferroptosis of astrocytes in cases of high-altitude TBI compared to those at low-altitude TBI. Analyzing transcription factors in depth, we found that Bach1 plays a crucial role in regulating key molecules that induce ferroptosis in astrocytes following high-altitude TBI. Down-regulation of Bach1 can effectively alleviate high-altitude TBI-induced neurological deficits and histopathological changes in mice. In conclusion, high-altitude hypoxia may significantly enhance the ferroptosis of astrocytes and aggravate TBI by up-regulating Bach1 expression. Our study provides a theoretical foundation for further understanding of the mechanism of high-altitude hypoxic TBI and targeted intervention therapy.

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.

The regulatory role of the Netrin-1/UNC5H3 pathway in neuronal pyroptosis after stroke

Currently, stroke is a disease with high disability and mortality risks and no effective treatment. The pathogenesis and molecular mechanisms of neuronal damage in stroke are highly complex. Pyroptosis participates in neuronal death after stroke. Thus, inhibiting pyroptosis could be a potential therapeutic method to improve the poor prognosis of stroke patients. However, the regulated mechanisms of pyroptosis remain unclear. Furthermore, although the role of Netrin-1 and its receptors in ischemic apoptosis is well-known, their specific functions in ischemia-induced pyroptosis are still unknown. The current study aimed to explore whether Netrin-1 and its receptor UNC5H3 could regulate pyroptosis after ischemic stroke. PC12 cells decreased Netrin-1 expression and increased UNC5H3 expression after OGD/R injury, subsequently leading to the dissociation of Netrin-1 from UNC5H3, accompanied by increased pyroptotic activity. UNC5H3 inhibition in the absence of Netrin-1 could inhibit OGD/R injury-induced cell pyroptosis. Furthermore, a decreased Netrin-1/UNC5H3 interaction could mitigate Netrin-1-elicited protective role against OGD/R injury. Additionally, Netrin-1 provided a neuroprotective effect against MCAO injury in vivo. Therefore, the Netrin-1/UNC5H3 pathway plays a regulatory role in neuronal pyroptosis after ischemic stroke, representing a novel therapeutic target and strategy for stroke therapy.

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.

Iron homeostasis and ferroptosis in human diseases: mechanisms and therapeutic prospects

Iron, an essential mineral in the body, is involved in numerous physiological processes, making the maintenance of iron homeostasis crucial for overall health. Both iron overload and deficiency can cause various disorders and human diseases. Ferroptosis, a form of cell death dependent on iron, is characterized by the extensive peroxidation of lipids. Unlike other kinds of classical unprogrammed cell death, ferroptosis is primarily linked to disruptions in iron metabolism, lipid peroxidation, and antioxidant system imbalance. Ferroptosis is regulated through transcription, translation, and post-translational modifications, which affect cellular sensitivity to ferroptosis. Over the past decade or so, numerous diseases have been linked to ferroptosis as part of their etiology, including cancers, metabolic disorders, autoimmune diseases, central nervous system diseases, cardiovascular diseases, and musculoskeletal diseases. Ferroptosis-related proteins have become attractive targets for many major human diseases that are currently incurable, and some ferroptosis regulators have shown therapeutic effects in clinical trials although further validation of their clinical potential is needed. Therefore, in-depth analysis of ferroptosis and its potential molecular mechanisms in human diseases may offer additional strategies for clinical prevention and treatment. In this review, we discuss the physiological significance of iron homeostasis in the body, the potential contribution of ferroptosis to the etiology and development of human diseases, along with the evidence supporting targeting ferroptosis as a therapeutic approach. Importantly, we evaluate recent potential therapeutic targets and promising interventions, providing guidance for future targeted treatment therapies against human diseases.

Elucidating the molecular mechanisms behind the therapeutic impact of median nerve stimulation on cognitive dysfunction post-traumatic brain injury

OBJECTIVE

Ferroptosis represents a form of regulated cellular death dependent upon iron and lipid peroxidation derivatives, holding considerable implications for cerebral and neurologic pathologies. In the present study, we endeavored to elucidate the molecular mechanisms governing ferroptosis and appraise the therapeutic value of electrical stimulation of median nerve in addressing cognitive impairments following traumatic brain injury (TBI), employing a rodent model.

METHODS

In this study, we established a rat model to investigate the cognitive impairments resulting from TBI, followed by the application of median nerve stimulation (MNS). Initially, rats received an intraperitoneal injection of Erastin (2 mg/kg) prior to undergoing MNS. After 24 h of MNS treatment, the rats were subjected to an open field test to evaluate their cognitive and motor functions. Subsequently, we conducted biochemical assays to measure the serum levels of GSH, MDA and SOD. The structural integrity and cellular morphology of hippocampal tissue were examined through H&E staining, Nissl staining and transmission electron microscopy. Additionally, we assessed the expression levels of proteins crucial for neuronal health and function in the hippocampus, including VEGF, SLC7A11, GPX4, Nrf2, α-syn, NEUN and PSD95.

RESULTS

Compared to the control group, rats in the stimulation group demonstrated enhanced mobility, reduced levels of tissue damage, a decrease in MDA concentration, and increased levels of GSH and SOD. Additionally, there was a significant upregulation in the expression of proteins critical for cellular defense and neuronal health, including GPX4, SLC7A11, Nrf2, VEGF, α-syn, NEUN, and PSD95 proteins. Conversely, rats in the Erastin group demonstrated decreased mobility, exacerbated pathological tissue damage, elevated MDA concentration, and decreased levels of GSH and SOD. There was also a notable decrease in the expression of GPX4, SLC7CA11, Nrf2, and VEGF proteins. The expression levels of α-syn, NEUN, and PSD95 were similarly diminished in the Erastin group. Each of these findings was statistically significant, indicating that MNS exerts neuroprotective effect in the hippocampal tissue of rats with TBI by inhibiting the ferroptosis pathway.

CONCLUSION

(1) MNS may enhance the cognitive and behavioral performance of rats after TBI; (2) MNS can play a neuroprotective role by promoting the expression of nerve injury-related proteins, alleviating oxidative stress and ferroptosis process; (3) MNS may inhibit ferroptosis of neuronal cells by activating Nrf2/ GPX4 signaling pathway, thereby improving cognitive impairment in TBI rats.

LncRNA H19 knockdown promotes neuropathologic and functional recovery via the Nrf2/HO-1 axis after traumatic brain injury

AIMS

Traumatic brain injury (TBI) stands as a significant concern in public health, frequently leading to enduring neurological deficits. Long non-coding RNA H19 (lncRNA H19) exerts a potential regulator role in the pathology of brain injury. This study investigates the effects of lncRNA H19 knockdown (H19-KD) on the pathophysiology of TBI and its potential neuroprotective mechanisms.

METHODS

Controlled cortical impact was employed to establish a stable TBI mouse model. The expression levels of various genes in perilesional cortex and striatum tissue after TBI was detected by RT-qPCR. AAV9-shRNA-H19 was injected into the lateral ventricle of mice to knockdown the expression of lncRNA H19. Various behavioral tests were performed to evaluate sensorimotor and cognitive functions after TBI. Immunofluorescence and Nissl staining were performed to assess brain tissue damage and neuroinflammation. The Nrf2 and HO-1 expression was performed by Western blot.

RESULTS

After TBI, the expression of lncRNA H19 was elevated in perilesional tissue and gradually reverted to baseline. Behavioral tests demonstrated that H19-KD significantly promoted the recovery of sensorimotor and cognitive functions after TBI. Besides, H19-KD reduced brain tissue loss, preserved neuronal integrity, and ameliorated white matter damage at the histological level. In addition, H19-KD restrained the pro-inflammatory and facilitated anti-inflammatory phenotypes of microglia/macrophages, attenuating the neuroinflammatory response after TBI. Furthermore, H19-KD promoted activation of the Nrf2/HO-1 axis after TBI, while suppression of Nrf2 partially abolished the neuroprotective effect.

CONCLUSION

H19-KD exerts neuroprotective effects after TBI in mice, partially mediated by the activation of the Nrf2/HO-1 axis.

Lysophosphatidic Acid Receptor 1 Plays a Pathogenic Role in Permanent Brain Ischemic Stroke by Modulating Neuroinflammatory Responses

Lysophosphatidic acid receptor 1 (LPA1) plays a critical role in brain injury following a transient brain ischemic stroke. However, its role in permanent brain ischemic stroke remains unknown. To address this, we investigated whether LPA1 could contribute to brain injury of mice challenged by permanent middle cerebral artery occlusion (pMCAO). A selective LPA1 antagonist (AM152) was used as a pharmacological tool for this investigation. When AM152 was given to pMCAO-challenged mice one hour after occlusion, pMCAO-induced brain damage such as brain infarction, functional neurological deficits, apoptosis, and blood-brain barrier disruption was significantly attenuated. Histological analyses demonstrated that AM152 administration attenuated microglial activation and proliferation in injured brain after pMCAO challenge. AM152 administration also attenuated abnormal neuroinflammatory responses by decreasing expression levels of pro-inflammatory cytokines while increasing expression levels of anti-inflammatory cytokines in the injured brain. As underlying effector pathways, NF-κB, MAPKs (ERK1/2, p38, and JNKs), and PI3K/Akt were found to be involved in LPA1-dependent pathogenesis. Collectively, these results demonstrate that LPA1 can contribute to brain injury by permanent ischemic stroke, along with relevant pathogenic events in an injured brain.

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.

circ_UTRN inhibits ferroptosis of ARJ21 cells to attenuate acute pancreatitis progression by regulating the miR-760-3p/FOXO1/GPX4 axis

Aim

To explore the function of circ_UTRN in acute pancreatitis (AP).

Methods

After exposing AR42J cells to caerulein, the levels of circ_UTRN, miR-760-3p, and glutathione peroxidase 4 (GPX4) were determined by quantitative polymerase chain reaction. Additionally, GPX4 and forkhead box O1 (FOXO1) protein levels were assessed by western blot. The levels of oxidative stress and ferroptosis in the supernatant of the treated AR42J cells were also assessed using commercial kits.

Results

circ_UTRN inhibited caerulein-induced oxidative stress and ferroptosis by binding with miR-760-3p. Additionally, miR-760-3p directly targeted FOXO1, thereby regulating GPX4 levels. Furthermore, GPX4 knockdown abolished the effect of miR-760-3p downregulation in AP.

Conclusion

circ_UTRN inhibited oxidative stress and ferroptosis by regulating the miR-760-3p/FOXO1/GPX4 axis. This is a potential new treatment strategy for AP.

Innovative Insights into Traumatic Brain Injuries: Biomarkers and New Pharmacological Targets

A traumatic brain injury (TBI) is a major health issue affecting many people across the world, causing significant morbidity and mortality. TBIs often have long-lasting effects, disrupting daily life and functionality. They cause two types of damage to the brain: primary and secondary. Secondary damage is particularly critical as it involves complex processes unfolding after the initial injury. These processes can lead to cell damage and death in the brain. Understanding how these processes damage the brain is crucial for finding new treatments. This review examines a wide range of literature from 2021 to 2023, focusing on biomarkers and molecular mechanisms in TBIs to pinpoint therapeutic advancements. Baseline levels of biomarkers, including neurofilament light chain (NF-L), ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1), Tau, and glial fibrillary acidic protein (GFAP) in TBI, have demonstrated prognostic value for cognitive outcomes, laying the groundwork for personalized treatment strategies. In terms of pharmacological progress, the most promising approaches currently target neuroinflammation, oxidative stress, and apoptotic mechanisms. Agents that can modulate these pathways offer the potential to reduce a TBI's impact and aid in neurological rehabilitation. Future research is poised to refine these therapeutic approaches, potentially revolutionizing TBI treatment.

Insufficient autophagy enables the nuclear factor erythroid 2-related factor 2 (NRF2) to promote ferroptosis in morphine-treated SH-SY5Y cells

RATIONALE

While morphine has important therapeutic value it is also one of the most widely abused drugs in the world. As a newly discovered style of cell death, ferroptosis is involved in the occurrence and development of many diseases, however, the current understanding of the relationship between ferroptosis and morphine is still limited.

OBJECTIVE

To clarify the role of opioid receptors in morphine-induced ferroptosis and to investigate the role of NRF2 in morphine-induced ferroptosis.

METHODS

We first used different doses of morphine (0, 0.5, 1, and 1.5 mM) to investigate morphine-induced ferroptosis in SH-SY5Y cells, and we choose 1.5 mM morphine for subsequent experiments. We next inhibited opioid receptors and NRF2 separately and examined their influence on morphine-induced ferroptosis. Finally, we tested morphine-induced insufficient autophagy.

RESULTS

Morphine triggered ferroptosis in a dose-dependent manner, which could be significantly rescued by the ferroptosis-specific inhibitor DFO. Moreover, GPX4 rather than xCT antiporter might be involved in morphine-induced ferroptosis. We also found naloxone could inhibit morphine-induced ferroptosis. Interestingly, our results demonstrated that NRF2 could promote rather than defend morphine-induced ferroptosis; this may be due to the increased p62-related insufficient autophagy.

CONCLUSION

Morphine-induced ferroptosis is regulated by the opioid receptor and GPX4 rather than the xCT antiporter. NRF2-mediated ferroptosis in morphine-exposed cells may stem from increased p62-related insufficient autophagy.

Broadening horizons: ferroptosis as a new target for traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide, with ~50 million people experiencing TBI each year. Ferroptosis, a form of regulated cell death triggered by iron ion-catalyzed and reactive oxygen species-induced lipid peroxidation, has been identified as a potential contributor to traumatic central nervous system conditions, suggesting its involvement in the pathogenesis of TBI. Alterations in iron metabolism play a crucial role in secondary injury following TBI. This study aimed to explore the role of ferroptosis in TBI, focusing on iron metabolism disorders, lipid metabolism disorders and the regulatory axis of system Xc-/glutathione/glutathione peroxidase 4 in TBI. Additionally, we examined the involvement of ferroptosis in the chronic TBI stage. Based on these findings, we discuss potential therapeutic interventions targeting ferroptosis after TBI. In conclusion, this review provides novel insights into the pathology of TBI and proposes potential therapeutic targets.

Fucoxanthin ameliorates traumatic brain injury by suppressing the blood-brain barrier disruption

Fucoxanthin is the most abundant marine carotenoid extracted from seaweed. Our previous study has shown that fucoxanthin inhibited oxidative stress after traumatic brain injury (TBI). However, the effects of fucoxanthin on TBI-induced blood-brain barrier (BBB) destruction have not been well understood. In the present study, we found that fucoxanthin improved neurological dysfunction, reduced brain edema, attenuated cortical lesion volume, and decreased dendrites loss after TBI in vivo. Moreover, fucoxanthin suppressed BBB leakage, preserved tight junction (TJ) and adherens junction (AJ) proteins, and inhibited MMP-9 expression. Furthermore, fucoxanthin alleviated apoptosis and ferroptosis, and activated mitophagy in endothelial cells (ECs) after TBI. However, the protection of fucoxanthin on BBB was attenuated when mitophagy was inhibited. Importantly, fucoxanthin also provided protective effects in bEnd.3 cells after TBI. Taken together, our results suggested that fucoxanthin played a key role in the protection of BBB after TBI through mitophagy.

Overexpression of GPX4 attenuates cognitive dysfunction through inhibiting hippocampus ferroptosis and neuroinflammation after traumatic brain injury

Ferroptosis is a newly discovered form of regulated cell death that is triggered primarily by lipid peroxidation. A growing body of evidence has implicated ferroptosis in the pathophysiology of traumatic brain injury (TBI). However, none of these studies focused its role on TBI-induced hippocampal injury. Here, we demonstrated that the distinct ferroptotic signature was detected in the injured hippocampus at the early stage of TBI. Besides, a prominent pro-ferroptosis environment was detected in the ipsilateral hippocampus after TBI, including elevated levels of arachidonic acid (AA), ACLS4, and ALXO15, and deficiency of GPX4. Subsequently, we used AAV-mediated Gpx4 overexpression to counteract ferroptosis in the hippocampus, and found that TBI-induced cognitive deficits were significantly alleviated after Gpx4 overexpression. Biochemical results also confirmed that TBI-induced hippocampal ferroptosis and synaptic damage were partially reversed by Gpx4 overexpression. In addition, Gpx4 overexpression inhibited TBI-induced neuroinflammation and peripheral macrophage infiltration. Interestingly, the results of transwell migration assay showed that ferroptotic neurons increased CCL2 expression and promoted iBMDM cell migration. However, this effect was inhibited by CCL2 antagonist, RS102895. These data suggested that inhibition of ferroptosis may be as a potential strategy to ameliorate TBI-induced cognitive deficits through blockade of hippocampal ferroptosis and neuroinflammation.