Protective effect of Xingnaojing injection on ferroptosis after cerebral ischemia injury in MCAO rats and SH-SY5Y cells

Traditional Chinese Medicine for Inhibiting Ferroptosis in Ischemic-Related Diseases

Ischemic-related diseases, such as myocardial infarction and stroke, are primarily driven by a deficit in oxygen supply leading to cellular damage and death. Ferroptosis has emerged as an important mechanism contributing to the progression of ischemic injury, characterized by iron-dependent lipid peroxidation. This review aims to provide a comprehensive overview of the significant mechanisms underlying ferroptosis in ischemic conditions and explores the potential effects of traditional Chinese medicines (TCMs) and their extracts. Numerous compounds extracted from TCMs, including flavonoids, polyphenols and terpenes, exhibit potent antiferroptotic effects by activating nuclear factor erythroid 2-related factor 2, upregulating glutathione peroxidase 4, inhibiting lipid peroxidation and so on. These properties render TCMs a promising candidate for developing novel ferroptosis therapeutic strategies. This review underscores the importance of investigating the interactions between ferroptosis and TCMs within the context of ischemic diseases. These findings provide valuable insights for future research to identify targets associated with ferroptosis regulation, thereby expanding the pharmacological perspective of TCMs in treating ischemic diseases and revealing the potential of novel therapeutic strategies. Additionally, this highlights the relevance of integrating traditional and modern medical approaches in addressing complex health issues.

Mesenchymal Stem Cells Prevent SLC39A14-Dependent Hepatocyte Ferroptosis through Exosomal miR-16-5p in Liver Graft

Ischemia-reperfusion injury (IRI) is the leading cause of hepatic graft dysfunction, resulting from hepatocyte damage. Nevertheless, given the few specialized therapeutics available in hepatic IRI, additional mechanistic insights into hepatocyte damage are required. Here, the protein solute carrier family 39 member 14 (SLC39A14) is identified as a pro-ferroptosis target in hepatocytes of human liver allografts through single-cell RNA sequencing analysis. SLC39A14 knockdown significantly mitigated hepatic IRI by preventing hepatocyte ferroptosis in vivo and in vitro. Mechanistically, the inhibition of SLC39A14 suppressed non-transferrin-bound iron (NTBI) uptake by hepatocytes, thereby reducing iron overload and cell ferroptosis. Moreover, human bone marrow-derived mesenchymal stem cells (hBMSCs) are found to exhibit a notable therapeutic effect on hepatic IRI by downregulating SLC39A14 expression. Exosomes derived from hBMSCs delivered abundant miR-16-5p into hepatocytes, which post-transcriptionally suppressed the expression of SLC39A14 and reduced cell ferroptosis induced by hepatic IRI. In conclusion, SLC39A14 triggers hepatic IRI by mediating NTBI uptake into hepatocytes and inducing hepatocyte ferroptosis. Moreover, hBMSC-based therapy is promising to reverse this progression of hepatic IRI.

Nasal administration of Xingnaojing biomimetic nanoparticles for the treatment of ischemic stroke

Xingnaojing injection (XNJ), is the first-line Chinese medicine injection approved for treating ischemic stroke (IS). XNJ can attenuate the inflammatory responses and oxidative stress, thus reversing neuronal damage of IS. This study aims to prepare the biomimetic nanoparticles (Bo-GEVs/XNJM) of nasal administration for IS treatment. The grapefruit extracellular vesicles (GEVs) loaded with microemulsions sourced from Xingnaojing injection (XNJM) are modified with borneol (Bo) to bypass the blood-brain barrier (BBB). Bo-GEVs/XNJM has the property of brain-targeting, and in vivo and in vitro experiments have validated that it has positive effects in reducing apoptosis, inhibiting oxidative stress, anti-inflammation, protecting mitochondrial function, and protecting the BBB. In summary, Bo-GEVs/XNJM has good neuroprotective effects, and provides an interventional method for the treatment of ischemic stroke.

Ferroptosis: mechanisms and therapeutic targets

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

Research Progress of Traditional Chinese Medicine in Treating Central Nervous System Diseases by Modulating Ferroptosis

A newly proposed form of programmed cell death, ferroptosis, is distinct in cellular morphology, biochemical characteristics, and genetic characteristics from apoptosis, autophagy, and necrosis. Its mechanisms primarily encompass iron overload, lipid peroxidation, and amino acid metabolisms. Extensive research confirms that ferroptosis is linked to the onset and progression of various diseases that pose a threat to the central nervous system (CNS), offering new directions and targets for the mechanistic study and pharmacotherapy of CNS diseases. Traditional Chinese Medicine (TCM), encompassing herbal medicines (extracts, compound formulations, injections, etc.), acupuncture, and moxibustion, boasts advantages over other treatments, such as multi-pathway and multi-target approaches and high safety. TCM has also demonstrated good efficacy in treating CNS diseases. Numerous studies indicate that TCM can modulate ferroptosis to treat CNS diseases, showing promising research prospects. This paper briefly outlines the pathways and mechanisms of ferroptosis and systematically summarizes the current status and progress of TCM in regulating various CNS diseases through the ferroptosis pathway, providing new insights and directions for future TCM treatments of CNS diseases.

The role of LCN2 in exacerbating ferroptosis levels in acute ischemic stroke injury

Due to the complex pathogenesis of acute ischemic stroke (AIS), further investigation into its underlying mechanisms is necessary. Presently, existing literature indicates a close association between ferroptosis and AIS injury; however, the precise mechanism and molecular target of ferroptosis in AIS injury remain elusive. By RNA sequencing, we found a significant increase in LCN2 expression in the ischemic cortex. In order to investigate the potential role of LCN2 in modulating AIS injury through the regulation of ferroptosis, we utilized RNA interference (RNAi) knockdown and gene overexpression experiments. The findings from experiments conducted both in vitro and in vivo revealed a marked increase in ferroptosis levels within the AIS model group. Suppression of the LCN2 gene resulted in a significant reduction in ferroptosis levels in OGD/R cells. Conversely, upregulation of LCN2 exacerbated ferroptosis levels in OGD/R cells. The results suggest that elevated levels of ferroptosis may result from heightened expression of LCN2, thereby exacerbating ischemia/reperfusion injury. This study indicates the involvement of ferroptosis in the pathogenesis of AIS and highlights LCN2 as a regulator of ferroptosis in AIS-induced injury, suggesting a potential therapeutic target for ischemic stroke.

Ferroptosis in Ischemic Stroke and Related Traditional Chinese Medicines

Stroke is a severe neurological disorder resulting from the rupture or blockage of blood vessels, leading to significant mortality and disability worldwide. Among the different types of stroke, ischemic stroke (IS) is the most prevalent, accounting for 70-80% of cases. Cell death following IS occurs through various mechanisms, including apoptosis, necrosis, and ferroptosis. Ferroptosis, a recently identified form of regulated cell death characterized by iron overload and lipid peroxidation, was first described by Dixon in 2012. Currently, the only approved pharmacological treatment for IS is recombinant tissue plasminogen activator (rt-PA), which is limited by a narrow therapeutic window and often results in suboptimal outcomes. Recent research has identified several traditional Chinese medicines (TCMs) that can inhibit ferroptosis, thereby mitigating the damage caused by IS. This review provides an overview of stroke, the role of ferroptosis in IS, and the potential of certain TCMs to inhibit ferroptosis and contribute to stroke treatment.

Melatonin improves stroke by inhibiting autophagy-dependent ferroptosis mediated by NCOA4 binding to FTH1

Ischemic stroke is a disease associated with high morbidity and disability rates; however, its pathogenesis remains elusive, and treatment options are limited. Ferroptosis, an iron-dependent form of cell death, represents a novel avenue for investigation. The objective of this study was to explore the role of melatonin in MCAO-induced ferroptosis and elucidate its underlying molecular mechanism. To simulate brain damage and neuronal injury caused by ischemic stroke, we established a mouse model of MCAO and an HT-22 cell model of OGD/R. The therapeutic efficacy of melatonin was assessed through measurements of infarct size, brain edema, and neurological scores. Additionally, qRT-PCR, WB analysis, and Co-IP assays were employed to investigate the impact of melatonin on ferroptosis markers such as NCOA4 and FTH1 expression levels. Confocal microscopy was utilized to confirm the colocalization between ferritin and lysosomes. Furthermore, we constructed a SIRT6 siRNA model to validate the regulatory effect exerted by SIRT6 on NCOA4 as well as their binding interaction. The present study provides initial evidence that melatonin possesses the ability to mitigate neuronal damage induced by MCAO and OGD/R. Assessment of markers for oxidative damage and ferroptosis revealed that melatonin effectively inhibits intracellular Fe2+ levels, thereby suppressing ferroptosis. Additionally, our findings demonstrate that melatonin modulates the interaction between FTH1 and NCOA4 via SIRT6, influencing ferritin autophagy without affecting cellular macroautophagy. These findings provide reliable data support for the promotion and application of melatonin in clinical practice.

N-ethylmaleimide-sensitive factor elicits a neuroprotection against ischemic neuronal injury by restoring autophagic/lysosomal dysfunction

Autophagosome-lysosome fusion defects play a critical role in driving autolysosomal dysfunction, leading to autophagic/lysosomal impairment in neurons following ischemic stroke. However, the mechanisms hindering autophagosome-lysosome fusion remain unclear. Soluble N-ethylmaleimide-sensitive factor (NSF) is an essential ATPase to reactivate STX17 and VAMP8, which are the paired molecules to mediate fusion between autophagosomes and lysosomes. However, NSF is frequently inactivated to inhibit the reactivation of STX17 and VAMP8 in ischemic neurons. Herein, we investigated whether autophagosome-lysosome fusion could be facilitated to alleviate autophagic/lysosomal impairment in ischemic neurons by over-expressing NSF. Rat model of middle cerebral artery occlusion (MCAO) and HT22 neuron ischemia model of oxygen-glucose deprivation (OGD) were prepared, respectively. The results demonstrated that NSF activity was significantly suppressed, accompanied by reduced expressions of STX17 and VAMP8 in penumbral neurons 48 h post-MCAO and in HT22 neurons 2 h post-OGD. Moreover, the attenuated autolysosome formation accompanied by autophagic/lysosomal dysfunction was observed. Thereafter, NSF activity in HT22 neurons was altered by over-expression and siRNA knockdown, respectively. After transfection with recombinant NSF-overexpressing lentiviruses, both STX17 and VAMP8 expressions were concurrently elevated to boost autophagosome-lysosome fusion, as shown by enhanced immunofluorescence intensity co-staining with LC3 and LAMP-1. Consequently, the OGD-created autophagic/lysosomal dysfunction was prominently ameliorated, as reflected by augmented autolysosomal functions and decreased autophagic substrates. By contrast, NSF knockdown conversely aggravated the autophagic/lysosomal impairment, and thereby exacerbated neurological damage. Our study indicates that NSF over-expression induces neuroprotection against ischemic neuronal injury by restoring autophagic/lysosomal dysfunction via the facilitation of autophagosome-lysosome fusion. Over-expression of NSF promotes fusion by reactivating STX17 and VAMP8. Black arrows represent the pathological process after cerebral ischemia, green arrows represent the mechanism of remission after NSF over-expression, and red arrows represent the effect on the pathological process after NSF knockdown.

Ferritinophagy and Ferroptosis in Cerebral Ischemia Reperfusion Injury

Cerebral ischemia-reperfusion injury (CIRI) is the second leading cause of death worldwide, posing a huge risk to human life and health. Therefore, investigating the pathogenesis underlying CIRI and developing effective treatments are essential. Ferroptosis is an iron-dependent mode of cell death, which is caused by disorders in iron metabolism and lipid peroxidation. Previous studies demonstrated that ferroptosis is also a form of autophagic cell death, and nuclear receptor coactivator 4(NCOA4) mediated ferritinophagy was found to regulate ferroptosis by interfering with iron metabolism. Ferritinophagy and ferroptosis are important pathogenic mechanisms in CIRI. This review mainly summarizes the link and regulation between ferritinophagy and ferroptosis and further discusses their mechanisms in CIRI. In addition, the potential treatment methods targeting ferritinophagy and ferroptosis for CIRI are presented, providing new ideas for the prevention and treatment of clinical CIRI in the future.

Isobolographic Analysis of the Cytoprotective Effect of Dapsone and Cannabidiol Alone or Combination upon Oxygen-Glucose Deprivation/Reoxygenation Model in SH-SY5Y Cells

Oxidative stress and apoptosis cell death are critical secondary damage mechanisms that lead to losing neighboring healthy tissue after cerebral ischemia. This study aims to characterize the type of interaction between dapsone (DDS) and cannabidiol (CBD) and its cytoprotective effect in an in vitro model of oxygen and glucose deprivation for 6 h followed by 24 h of reoxygenation (OGD/R), using the SH-SY5Y cell line. For the combined concentrations, an isobolographic study was designed to determine the optimal concentration-response combinations. Cell viability was evaluated by measuring the lactate dehydrogenase (LDH) release and 3-[4, 5-dimethyl-2-thiazolyl]-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assays. Also, the reactive oxygen species (ROS) and reduced glutathione (GSH) levels were analyzed as oxidative stress markers. Finally, caspase-3 activity was evaluated as a marker cell death by apoptosis. The results showed a decrease in cell viability, an increase in oxidant stress, and the activity of caspase-3 by the effect of OGD/R. Meanwhile, both DDS and CBD demonstrated antioxidant, antiapoptotic, and cytoprotective effects in a concentration-response manner. The isobolographic study indicated that the concentration of 2.5 µM of DDS plus 0.05 µM of CBD presented a synergistic effect so that in treatment, cell death due to OGD/R decreased. The findings indicate that DDS-CBD combined treatment may be a helpful therapy in cerebral ischemia with reperfusion.

Therapeutic potential of salvigenin to combat atrazine induced liver toxicity in rats via regulating Nrf-2/Keap-1 and NF-κB pathway

Atrazine (ATR) is the second most extensively used herbicide which adversely affects the body organs including liver. Salvigenin (SGN) is a flavonoid which demonstrates a wide range of biological and pharmacological abilities. This study was planned to assess the protective ability of SGN to avert ATR induced liver damage in rats. Thirty-two rats (Rattus norvegicus) were divided into four groups including control, ATR (5 mg/kg), ATR (5 mg/kg) + SGN (10 mg/kg) and SGN (10 mg/kg) alone supplemented group. ATR exposure reduced the expression of Nrf-2 while instigating an upregulation in Keap-1 expression. Furthermore, the activities of catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), heme‑oxygenase-1 (HO-1) and glutathione reductase (GSR) contents were decreased while increasing reactive oxygen species (ROS) and malondialdehyde (MDA) levels after ATR treatment. Moreover, ATR poisoning increased the levels of ALT, AST, and ALP while reducing the levels of total proteins, and albumin in hepatic tissues of rats. Besides, ATR administration escalated the expressions of Bax and Caspase-3 while inducing a downregulation in the expressions of Bcl-2. Similarly, ATR intoxication increased the levels of Interleukin-6 (IL-6), Nuclear factor kappa-B (NF-κB), Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and the activity of cyclooxygenase-2 (COX-2). Furthermore, ATR disrupted the normal histology of hepatic tissues. However, SGN treatment remarkably protected the liver tissues via regulating antioxidant, anti, inflammatory, anti-apoptotic as well as histology parameters. Therefore, it is concluded that SGN can be used as therapeutic agent to combat ATR-induced hepatotoxicity.

Progress of medicinal plants and their active metabolites in ischemia-reperfusion injury of stroke: a novel therapeutic strategy based on regulation of crosstalk between mitophagy and ferroptosis

The death of cells can occur through various pathways, including apoptosis, necroptosis, mitophagy, pyroptosis, endoplasmic reticulum stress, oxidative stress, ferroptosis, cuproptosis, and disulfide-driven necrosis. Increasing evidence suggests that mitophagy and ferroptosis play crucial regulatory roles in the development of stroke. In recent years, the incidence of stroke has been gradually increasing, posing a significant threat to human health. Hemorrhagic stroke accounts for only 15% of all strokes, while ischemic stroke is the predominant type, representing 85% of all stroke cases. Ischemic stroke refers to a clinical syndrome characterized by local ischemic-hypoxic necrosis of brain tissue due to various cerebrovascular disorders, leading to rapid onset of corresponding neurological deficits. Currently, specific therapeutic approaches targeting the pathophysiological mechanisms of ischemic brain tissue injury mainly include intravenous thrombolysis and endovascular intervention. Despite some clinical efficacy, these approaches inevitably lead to ischemia-reperfusion injury. Therefore, exploration of treatment options for ischemic stroke remains a challenging task. In light of this background, advancements in targeted therapy for cerebrovascular diseases through mitophagy and ferroptosis offer a new direction for the treatment of such diseases. In this review, we summarize the progress of mitophagy and ferroptosis in regulating ischemia-reperfusion injury in stroke and emphasize their potential molecular mechanisms in the pathogenesis. Importantly, we systematically elucidate the role of medicinal plants and their active metabolites in targeting mitophagy and ferroptosis in ischemia-reperfusion injury in stroke, providing new insights and perspectives for the clinical development of therapeutic drugs for these diseases.

Xingnaojing injection alleviates cerebral ischemia/reperfusion injury through regulating endoplasmic reticulum stress in Vivo and in Vitro

Background

Xingnaojing (XNJ) injection, an extract derived from traditional Chinese medicine, is commonly used to treat ischemic stroke (IS). Previous studies have shown that XNJ has the ability to alleviate apoptosis in cerebral ischemia-reperfusion injury. However, the potential mechanisms have not been clarified.

Objective

To identify the neuroprotective effect of XNJ and explore whether XNJ inhibits cell apoptosis associated with endoplasmic reticulum stress (ERS) after IS.

Methods

In this study, cultured hippocampal neurons from mouse embryos and Sprague-Dawley rats were assigned randomly to four groups: sham, model, XNJ, and edaravone. The treatment groups were administered 2 h after modelling. Neurological deficit scores and motor performance tests were performed after 24 h of modelling. Additionally, pathomorphology, cell apoptosis and calcium content were evaluated. To ascertain the expression of ERS proteins, western blotting and polymerase chain reaction were employed.

Results

The results indicated that XNJ treatment resulted in a notable decrease in infarct volume, apoptosis and missteps compared with the model group. XNJ also exhibited improvements in neurological function, grip strength and motor time. The calcium content significantly reduced in XNJ group. The XNJ administration resulted in a reduction in the levels of proteins associated with ERS including CHOP, GRP78, Bax, caspase-12, caspase-9, and cleaved-caspase-3, but an increase of the Bcl-2/Bax ratio. Furthermore, the downregulation of mRNA expression of CHOP, GRP78, caspase-12, caspase-9, and caspase-3 was confirmed in both cultured neurons and rat model.

Conclusion

These findings suggest that XNJ may alleviate apoptosis by modulating the ERS-induced apoptosis pathway, making it a potential novel therapeutic approach for ischemic stroke.

Traditional Chinese medicines treat ischemic stroke and their main bioactive constituents and mechanisms

Ischemic stroke (IS) remains one of the leading causes of death and disability in humans. Unfortunately, none of the treatments effectively provide functional benefits to patients with IS, although many do so by targeting different aspects of the ischemic cascade response. The advantages of traditional Chinese medicine (TCM) in preventing and treating IS are obvious in terms of early treatment and global coordination. The efficacy of TCM and its bioactive constituents has been scientifically proven over the past decades. Based on clinical trials, this article provides a review of commonly used TCM patent medicines and herbal decoctions indicated for IS. In addition, this paper also reviews the mechanisms of bioactive constituents in TCM for the treatment of IS in recent years, both domestically and internationally. A comprehensive review of preclinical and clinical studies will hopefully provide new ideas to address the threat of IS.

Glycosides of Buyang Huanwu decoction inhibits pyroptosis associated with cerebral ischemia-reperfusion through Nrf2-mediated antioxidant signaling pathway both in vivo and in vitro

BACKGROUND

Glycosides are the pharmacodynamic substances of Buyang Huanwu Decoction (BYHWD) and they exert a protective effect in the brain by inhibiting neuronal pyroptosis of cerebral ischemia-reperfusion (CIR). However, the mechanism by which glycosides regulate neuronal pyroptosis of CIR is still unclear.

PURPOSE

A significant part of this study aimed to demonstrate whether glycosides have an anti-pyroptotic effect on CIR by nuclear factor erythroid 2-related factor (Nrf2)-mediated antioxidative mechanism.

METHODS

Rats were used in vivo models of middle cerebral artery occlusion and reperfusion (MCAO/R). Neuroprotective effect of glycosides after Nrf2 inhibiting was observed by nerve function score, Nissl staining, Nrf2 fluorescence staining and pyroptotic proteins detection. SH-SY5Y cells were used in vitro models of oxygen-glucose deprivation/reperfusion (OGD/R). Glycosides was evaluated for their effects by measuring cell morphology, survival rate, lactate dehydrogenase (LDH) rate and expression of pyroptotic proteins. Nrf2 si-RNA 54-1 interference with lentivirus was used to create silenced Nrf2 SH-SY5Y cells (si-Nrf2-SH-SY5Y). Glycosides were evaluated on si-Con-SH-SY5Y and si-Nrf2-SH-SY5Y cells based on the expression of Nrf2 signaling pathway, pyroptotic proteins and cell damage manifestation.

RESULTS

In vivo, glycosides significantly promoted the fluorescence level of nuclear Nrf2, added more Nissl bodies, reduced neurological function scores and inhibited the pyroptotic proteins level. In vitro, glycosides significantly repaired the morphological damage of cells, promoted the survival rate, reduced the LDH rate, inhibited the pyroptosis. Moreover, antioxidant activity of glycosides was enhanced via Nrf2 activation. Both Nrf2 blocking in vivo and Nrf2 silencing in vitro significantly weakened the pyroptosis inhibitory and neuroprotective effects of glycosides.

CONCLUSION

These results suggested for the first time that glycosides inhibited neuronal pyroptosis by regulating the Nrf2-mediated antioxidant stress pathway, thereby exerting brain protection of CIR. As a result of this study, This study improved understanding of the pharmacodynamics and mechanism of BYHWD, as well as providing a Traditional Chinese Medicine (TCM) treatment strategy for CIR .

Enriched environment attenuates ferroptosis after cerebral ischemia/reperfusion injury by regulating iron metabolism

Preventing neuronal death after ischemic stroke (IS) is crucial for neuroprotective treatment, yet current management options are limited. Enriched environment (EE) is an effective intervention strategy that promotes the recovery of neurological function after cerebral ischemia/reperfusion (I/R) injury. Ferroptosis has been identified as one of the mechanisms of neuronal death during IS, and inhibiting ferroptosis can reduce cerebral I/R injury. Our previous research has demonstrated that EE reduced ferroptosis by inhibiting lipid peroxidation, but the underlying mechanism still needs to be investigated. This study aims to explore the potential molecular mechanisms by which EE modulates iron metabolism to reduce ferroptosis. The experimental animals were randomly divided into four groups based on the housing environment and the procedure the animals received: the sham-operated + standard environment (SSE) group, the sham-operated + enriched environment (SEE) group, the ischemia/reperfusion + standard environment (ISE) group, and the ischemia/reperfusion + enriched environment (IEE) group. The results showed that EE reduced IL-6 expression during cerebral I/R injury, hence reducing JAK2-STAT3 pathway activation and hepcidin expression. Reduced hepcidin expression led to decreased DMT1 expression and increased FPN1 expression in neurons, resulting in lower neuronal iron levels and alleviated ferroptosis. In addition, EE also reduced the expression of TfR1 in neurons. Our research suggested that EE played a neuroprotective role by modulating iron metabolism and reducing neuronal ferroptosis after cerebral I/R injury, which might be achieved by inhibiting inflammatory response and down-regulating hepcidin expression.

Determining the chemical profile of Caragana jubata (Pall.) Poir. by UPLC-QTOF-MS analysis and evaluating its anti-ischemic stroke effects

ETHNOPHARMACOLOGICAL RELEVANCE

Caragana jubata, belonging to the Leguminosae family, is a shrubby medicinal plant distributed in high-altitude areas of China. The red heartwood of C. jubata is the original source of 'zuomuxing', a Tibetan medicine that promotes blood circulation and removes blood stasis to treat different diseases associated with the blood.

AIM OF THE STUDY

To date, research on the chemical constituents of C. jubata remains very limited. The anti-ischemic stroke (anti-IS) effects of this plant have not been studied. The aim of the present study was to analyze the chemical profile of C. jubata, establish various anti-IS models to comprehensively evaluate the anti-IS effects of C. jubata, and explore the mechanism of action.

MATERIALS AND METHODS

Ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) was chosen to analyze the chemical profile. A middle cerebral artery occlusion reperfusion (MCAO/R) model, zebrafish cerebral thrombosis model, and oxygen-glucose deprivation/reperfusion (OGD/R) model in PC12/BV2 cells were used to thoroughly evaluate the anti-IS effects of C. jubata. Additionally, western blotting and immunofluorescence staining were used to detect the mechanism of action.

RESULTS

Fifty-three compounds were identified from a 95% ethanol extract of C. jubata (ECJ) by UPLC-QTOF-MS analysis. 17 and 7 compounds were identified from C. jubata and the genus Caragana for the first time. ECJ was found to attenuate infarct size and reduce brain edema and neurological scores in MCAO/R rats. ECJ notably reduced the zebrafish cerebral thrombosis incidence in a dose-dependent manner compared with that in the model group. Surprisingly, compared to the positive control drug aspirin, 50 μg/ml ECJ exhibited a better therapeutic effect than aspirin at 30 μg/ml. Additionally, ECJ significantly increased the viability of PC12/BV2 cells injured by OGD/R. Moreover, ECJ inhibited the protein expression of M1 markers (TNF-α, iNOS, and IL-1β) and increased that of M2 markers (Arg-1 and CD206) in OGD/R-injured BV2 cells. ECJ significantly decreased the immunofluorescence intensity of CD16 and increased that of CD206.

CONCLUSIONS

The results from UPLC-QTOF-MS analysis showed that ECJ was rich in flavonoids. The results from pharmacological experiments verified the anti-IS effects of C. jubata in vivo and in vitro for the first time. In addition, ECJ could regulate the polarization of microglia. The present study highlights the medicinal value of C. jubata, thus providing a theoretical basis for the further development of new drugs from C. jubata to treat IS.

Ferroptosis Regulated by Hypoxia in Cells

Ferroptosis is an oxidative damage-related, iron-dependent regulated cell death with intracellular lipid peroxide accumulation, which is associated with many physiological and pathological processes. It exhibits unique features that are morphologically, biochemically, and immunologically distinct from other regulated cell death forms. Ferroptosis is regulated by iron metabolism, lipid metabolism, anti-oxidant defense systems, as well as various signal pathways. Hypoxia, which is found in a group of physiological and pathological conditions, can affect multiple cellular functions by activation of the hypoxia-inducible factor (HIF) signaling and other mechanisms. Emerging evidence demonstrated that hypoxia regulates ferroptosis in certain cell types and conditions. In this review, we summarize the basic mechanisms and regulations of ferroptosis and hypoxia, as well as the regulation of ferroptosis by hypoxia in physiological and pathological conditions, which may contribute to the numerous diseases therapies.

Sevoflurane Postconditioning Attenuates Cerebral Ischemia-Reperfusion Injury by Inhibiting SP1/ACSL4-Mediated Ferroptosis

Sevoflurane is the most commonly used anesthetic in clinical practice and exerts a protective effect on cerebral ischemia-reperfusion (I/R) injury. This study aims to elucidate the molecular mechanism by which sevoflurane postconditioning protects against cerebral I/R injury. Oxygen-glucose deprivation/reperfusion (OGD/R) model in vitro and the middle cerebral artery occlusion (MCAO) model in vivo were established to simulate cerebral I/R injury. Sevoflurane postconditioning reduced neurological deficits, cerebral infarction, and ferroptosis after I/R injury. Interestingly, sevoflurane significantly inhibited specificity protein 1 (SP1) expression in MACO rats and HT22 cells exposed to OGD/R. SP1 overexpression attenuated the neuroprotective effects of sevoflurane on OGD/R-treated HT22 cells, evidenced by reduced cell viability, increased apoptosis, and cleaved caspase-3 expression. Furthermore, chromatin immunoprecipitation and luciferase experiments verified that SP1 bound directly to the ACSL4 promoter region to increase its expression. In addition, sevoflurane inhibited ferroptosis via SP1/ACSL4 axis. Generally, our study describes an anti-ferroptosis effect of sevoflurane against cerebral I/R injury via downregulating the SP1/ASCL4 axis. These findings suggest a novel sight for cerebral protection against cerebral I/R injury and indicate a potential therapeutic approach for a variety of cerebral diseases.