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BACKGROUND: Cerebral ischemia/reperfusion injury (CIRI) is still a complicated disease with high fatality rates worldwide. Transmembrane Protein 79 (TMEM79) regulates inflammation and oxidative stress in some other diseases. METHODS: CIRI mouse model was established using C57BL/6J mice through middle cerebral artery occlusion-reperfusion (MCAO/R), and BV2 cells were subjected to oxygen and glucose deprivation/reoxygenation (OGD/R) to simulate CIRI. Brain tissue or BV2 cells were transfected or injected with lentivirus-carried TMEM79 overexpression vector. The impact of TMEM79 on CIRI-triggered oxidative stress was ascertained by dihydroethidium (DHE) staining and examination of oxidative stress indicators. Regulation of TMEM79 in neuronal apoptosis and inflammation was determined using TUNEL staining and ELISA. RESULTS: TMEM79 overexpression mitigated neurological deficit induced by MCAO/R and decreased the extent of cerebral infarct. TMEM79 prevented neuronal death in brain tissue of MCAO/R mouse model and suppressed inflammatory response by reducing inflammatory cytokines levels. Moreover, TMEM79 significantly attenuated inflammation and oxidative stress caused by OGD/R in BV2 cells. TMEM79 facilitated the activation of Nrf2 and inhibited NLRP3 and caspase-1 expressions. Rescue experiments indicated that the Nrf2/NLRP3 signaling pathway mediated the mitigative effect of TMEM79 on CIRI in vivo and in vitro. CONCLUSION: Overall, TMEM79 was confirmed to attenuate CIRI via regulating the Nrf2/NLRP3 signaling pathway.

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Modelos Animales de Enfermedad , Infarto de la Arteria Cerebral Media , Proteínas de la Membrana , Factor 2 Relacionado con NF-E2 , Proteína con Dominio Pirina 3 de la Familia NLR , Estrés Oxidativo , Daño por Reperfusión , Animales , Humanos , Masculino , Ratones , Apoptosis , Isquemia Encefálica/metabolismo , Línea Celular , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Inflamación/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Ratones Endogámicos C57BL , Neuronas/metabolismo , Neuronas/patología , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Daño por Reperfusión/metabolismo , Transducción de Señal

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Cerebral ischemia-reperfusion injury (CIRI), a prevalent stroke-related complication, can lead to severe brain damage. Inflammation is a crucial factor in CIRI pathogenesis, and the complement component 3a receptor (C3aR) could be a key mediator in the post-CIRI inflammatory cascade. In this study, the role of C3aR in CIRI was investigated utilizing a middle cerebral artery occlusion (MCAO) model in C3aR knockout (KO) mice. Magnetic resonance imaging (MRI) and neurofunctional assessments revealed that C3aR KO mice exhibited significantly diminished cerebral infarction and improved neurological impairments. Consequently, the focus shifted to searching for a small molecule antagonist of C3aR. JR14a, a new potent thiophene antagonist of C3aR, was injected intraperitoneally into mice 1-h post-MCAO model implementation. The mass spectrometry (MS) results indicated the ability of JR14a to penetrate the blood-brain barrier. Subsequent TTC staining and neurofunctional assessments revealed the efficacy of JR14a in reducing cerebral infarct volume and neurological impairment following MCAO. In addition, immunofluorescence (IF) and immunohistochemistry (IHC) demonstrated attenuated microglial activation, neutrophil infiltration, and blood-brain barrier disruption by JR14a in the MCAO model. Furthermore, enzyme-linked immunosorbent assay (ELISA) and Western blotting supported the role of JR14a in downregulating the expression levels of C3aR, tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6), as well as the phosphorylation of p65. In conclusion, the findings suggested that C3aR could be a potential therapeutic target for CIRI, and JR14a emerged as a promising treatment candidate.

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Infarto de la Arteria Cerebral Media , Ratones Noqueados , Enfermedades Neuroinflamatorias , Daño por Reperfusión , Animales , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Ratones , Masculino , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/metabolismo , Ratones Endogámicos C57BL , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Receptores de Complemento/antagonistas & inhibidores , Receptores de Complemento/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Modelos Animales de Enfermedad , Microglía/efectos de los fármacos , Microglía/metabolismo , Tiofenos/farmacología , Tiofenos/uso terapéutico , Fármacos Neuroprotectores/farmacología , Inflamación/tratamiento farmacológico , Inflamación/metabolismo

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Ischemia/reperfusion (I/R) injury is a pathological event that results in reperfusion due to low blood flow to an organ. Cerebral ischemia is a common cerebrovascular disease with high mortality, and reperfusion is the current standard intervention. However, reperfusion may further induce cellular damage and dysfunction known as cerebral ischemia/reperfusion injury (CIRI). Currently, strategies for the clinical management of CIRI are limited, necessitating the exploration of novel and efficacious treatment modalities for the benefit of patients. PI3K/Akt signaling pathway is an important cellular process associated with the disease. Stimulation of the PI3K/Akt pathway enhances I/R injury in multiple organs such as heart, brain, lung, and liver. It stands as a pivotal signaling pathway crucial for diminishing cerebral infarction size and safeguarding the functionality of brain tissue after CIRI. During CIRI, activation of the PI3K/Akt pathway exhibits a protective effect on CIRI. Furthermore, activation of the PI3K/Akt pathway has the potential to augment the activity of antioxidant enzymes, resulting in a decrease in reactive oxygen species (ROS) and the associated oxidative stress. Meanwhile, PI3K/Akt plays a neuroprotective role by inhibiting inflammatory responses and apoptosis. For example, PI3K/Akt interacts with NF-κB, Nrf2, and MAPK signaling pathways to mitigate CIRI. This article is aimed to explore the pivotal role and underlying mechanism of PI3K/Akt in ameliorating CIRI and investigate the influence of ischemic preconditioning and post-processing, as well as the impact of pertinent drugs or activators targeting the PI3K/Akt pathway on CIRI. The primary objective is to furnish compelling evidence supporting the activation of PI3K/Akt in the context of CIRI, elucidating its mechanistic intricacies. By doing so, the paper aims to underscore the critical contribution of PI3K/Akt in mitigating CIRI, providing a theoretical foundation for considering the PI3K/Akt pathway as a viable target for CIRI treatment.

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Cerebral ischemia/reperfusion injury (CIRI) is a major contributor to poor prognosis of ischemic stroke. Flavonoids are a broad family of plant polyphenols which are abundant in traditional Chinese medicine (TCM) and have beneficial effects on several diseases including ischemic stroke. Accumulating studies have indicated that flavonoids derived from herbal TCM are effective in alleviating CIRI after ischemic stroke in vitro or in vivo, and exhibit favourable therapeutical potential. Herein, we systematically review the classification, metabolic absorption, neuroprotective efficacy, and mechanisms of TCM flavonoids against CIRI. The literature suggest that flavonoids exert potential medicinal functions including suppressing excitotoxicity, Ca2+ overloading, oxidative stress, inflammation, thrombin's cellular toxicity, different types of programmed cell deaths, and protecting the blood-brain barrier, as well as promoting neurogenesis in the recovery stage following ischemic stroke. Furthermore, we identified certain matters that should be taken into account in future research, as well as proposed difficulties and opportunities in transforming TCM-derived flavonoids into medications or functional foods for the treatment or prevention of CIRI. Overall, in this review we aim to provide novel ideas for the identification of new prospective medication candidates for the therapeutic strategy against ischemic stroke.

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Stroke is a well-known neurological disorder that carries significant morbidity and mortality rates worldwide. Cerebral Ischemic Stroke (CIS), the most common subtype of stroke, occurs when thrombosis or emboli form elsewhere in the body and travel to the brain, leading to reduced blood perfusion. Cerebral Ischemia/Reperfusion Injury (CIRI) is a common complication of CIS and arises when blood flow is rapidly restored to the brain tissue after a period of ischemia. The therapeutic approaches currently recognized for CIS, such as thrombolysis and thrombectomy, have notable side effects that limit their clinical application. Recently, there has been growing interest among researchers in exploring the potential of herbal agents for treating various disorders and malignancies. One such herbal agent with medicinal applications is tanshinone IIA, an active diterpene quinone extracted from Salvia miltiorrhiza Bunge. Tanshinone IIA has shown several pharmacological benefits, including anti-inflammatory, antioxidant, anti-apoptotic, and neuroprotective properties. Multiple studies have indicated the protective role of tanshinone IIA in CIS and CIRI. This literature review aims to summarize the current findings regarding the molecular mechanisms through which this herbal compound improves CIS and CIRI.

Asunto(s)

Abietanos , Accidente Cerebrovascular Isquémico , Daño por Reperfusión , Abietanos/farmacología , Abietanos/química , Abietanos/uso terapéutico , Humanos , Daño por Reperfusión/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Animales , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/uso terapéutico , Isquemia Encefálica/tratamiento farmacológico , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/uso terapéutico

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Chrysin is a natural flavonoid with powerful neuroprotective capacity. Cerebral ischemia/reperfusion injury (CIRI) is associated with oxidative stress and ferroptosis. Hypoxia-inducible factor 1α (HIF-1α) and ceruloplasmin (CP) are the critical targets for oxidation reactions and iron transport. But the regulatory mechanism between them is still unclear. Transient middle cerebral artery occlusion (tMCAO) model in rats and oxygen and glucose deprivation/re-oxygenation (OGD/R) model in PC12 cells were applied. Pathological tissue staining and biochemical kit were used to evaluate the effect of chrysin. The relationship between HIF-1α and CP was verified by transcriptomics, qRT-PCR and Western blot. In CIRI, HIF-1α/CP loop was discovered to be the regulatory pathway of ferroptosis. CIRI led to activation and nuclear translocation of HIF-1α, which promoted CP transcription and translation, and downstream ferroptosis. Inhibition of HIF-1α had opposite effect on CP and ferroptosis regulation. Overexpression of CP increased the expression of HIF-1α, nevertheless, inhibited the nuclear translocation of HIF-1α and alleviated CIRI. Silencing CP promoted HIF-1α elevation in nucleus and aggravated CIRI. Mechanistically, chrysin restrained HIF-1α nuclear translocation, thereby inhibiting CP transcription and translation, which in turn reduced downstream HIF-1α expression and mitigated ferroptosis in CIRI. Our results highlight chrysin restrains ferroptosis in CIRI through HIF-1α/CP loop.

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Ceruloplasmina , Ferroptosis , Flavonoides , Subunidad alfa del Factor 1 Inducible por Hipoxia , Ratas Sprague-Dawley , Daño por Reperfusión , Flavonoides/farmacología , Animales , Daño por Reperfusión/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/patología , Ferroptosis/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ratas , Células PC12 , Masculino , Ceruloplasmina/metabolismo , Ceruloplasmina/genética , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/patología , Fármacos Neuroprotectores/farmacología , Transducción de Señal/efectos de los fármacos

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Solasonine (SS), the main active ingredient of Solanum nigrum L., has been reported to possess a variety of pharmacological properties. A recent study demonstrated a neuroprotective effect of SS in a mouse nerve injury model. However, its protective effects on cerebral ischemia/reperfusion injury (CIRI) remain to be elucidated. We investigated herein the in vitro and in vivo neuroprotective effects of SS. Primary hippocampal neurons were exposed to oxygen and glucose deprivation/reoxygenation (OGD/R) to construct an in vitro model while rats were treated with middle cerebral artery occlusion/reperfusion (MCAO/R) to establish an in vivo CIRI model. The results showed that SS reduced OGD/R-induced inflammatory responses of neurons by blocking secretion of TNF-α, IL-1ß and IL-6. Moreover, SS ameliorated OGD/R-induced oxidative stress in neurons by decreasing the level of ROS and MDA and increasing the activity of SOD and GPx. We also found that SS protected neurons from OGD/R-induced apoptosis by down-regulating bax and cleaved caspase-3 and up-regulating bcl-2. The in vivo results revealed that SS administration reduced the infarct volume and alleviated the neurological deficit of MCAO/R rats as well as diminished neuronal damages in these rats. Our investigation on the underlying mechanisms indicated that the neuroprotective effect of SS on CIRI may be associated with the TLR4/MyD88/NF-κB and AMPK/Nrf2/HO-1 pathways. Taken together, these findings demonstrate that SS ameliorates CIRI via suppressing TLR4/MyD88/NF-κB pathway and activating AMPK/Nrf2/HO-1 pathway.

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Ischemia/reperfusion (I/R) injury is a pathological process wherein reperfusion of an ischemic organ or tissue exacerbates the injury, posing a significant health threat and economic burden to patients and their families. I/R triggers a multitude of physiological and pathological events, such as inflammatory responses, oxidative stress, neuronal cell death, and disruption of the blood-brain barrier (BBB). Hence, the development of effective therapeutic strategies targeting the pathological processes resulting from I/R is crucial for the rehabilitation and long-term enhancement of the quality of life in patients with cerebral ischemia/reperfusion injury (CIRI). Traditional Chinese medicine (TCM) monomers refer to bioactive compounds extracted from Chinese herbal medicine, possessing anti-inflammatory and antioxidative effects, and the ability to modulate programmed cell death (PCD). TCM monomers have emerged as promising candidates for the treatment of CIRI and its subsequent complications. Preclinical studies have demonstrated that TCM monomers can enhance the recovery of neurological function following CIRI by mitigating oxidative stress, suppressing inflammatory responses, reducing neuronal cell death and functional impairment, as well as minimizing cerebral infarction volume. The neuroprotective effects of TCM monomers on CIRI have been extensively investigated, and a comprehensive understanding of their mechanisms can pave the way for novel approaches to I/R treatment. This review aims to update and summarize evidence of the protective effects of TCMs in CIRI, with a focus on their role in modulating oxidative stress, inflammation, PCD, glutamate excitotoxicity, Ca2+ overload, as well as promoting blood-brain barrier repairment and angiogenesis. The main objective is to underscore the significant contribution of TCM monomers in alleviating CIRI.

RESUMEN

Activin A (Act A) is a member of the transforming growth factor-ß (TGF-ß) superfamily and can protect against ischemic cerebral injury. Ferroptosis, a newly discovered type of programmed cell death, contributes to the pathogenesis of cerebral ischemia-reperfusion injury (CIRI). However, little is known on whether Act A can modulate neuronal ferroptosis to protect against CIRI in a mouse model of middle cerebral artery occlusion (MCAO) and an HT22 cell model of oxygen-glucose deprivation/reoxygenation (OGD/R). The results indicated that Act A treatment relieved CIRI by improving neurological deficits and reducing the infarct volume in mice. MCAO stimulated iron accumulation and malondialdehyde formation and upregulated ACSL4 expression but downregulated GPX4 expression, a hallmark of ferroptosis in the brain of mice. Treatment with Act A significantly mitigated MCAO-triggered ferroptosis in the brain of mice. Furthermore, Act A treatment enhanced the MCAO-upregulated nuclear factor erythroid-2-related factor 2 (Nrf2) expression in the brains of mice. Similar results were observed in HT22 cells following OGD/R and pretreatment with Act A. The neuronal protective effect of Act A in HT22 cells was attenuated by treatment with ML385, an Nrf2 inhibitor. To conclude, Act A attenuated CIRI by enhancing Nrf2 expression and inhibiting neuronal ferroptosis.

Asunto(s)

Isquemia Encefálica , Ferroptosis , Fármacos Neuroprotectores , Daño por Reperfusión , Ratones , Animales , Fármacos Neuroprotectores/farmacología , Factor 2 Relacionado con NF-E2/metabolismo , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/metabolismo , Oxígeno , Glucosa , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo

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Ischemic stroke (IS) accounts for more than 80% of the total stroke, which represents the leading cause of mortality and disability worldwide. Cerebral ischemia/reperfusion injury (CI/RI) is a cascade of pathophysiological events following the restoration of blood flow and reoxygenation, which not only directly damages brain tissue, but also enhances a series of pathological signaling cascades, contributing to inflammation, further aggravate the damage of brain tissue. Paradoxically, there are still no effective methods to prevent CI/RI, since the detailed underlying mechanisms remain vague. Mitochondrial dysfunctions, which are characterized by mitochondrial oxidative stress, Ca2+ overload, iron dyshomeostasis, mitochondrial DNA (mtDNA) defects and mitochondrial quality control (MQC) disruption, are closely relevant to the pathological process of CI/RI. There is increasing evidence that mitochondrial dysfunctions play vital roles in the regulation of programmed cell deaths (PCDs) such as ferroptosis and PANoptosis, a newly proposed conception of cell deaths characterized by a unique form of innate immune inflammatory cell death that regulated by multifaceted PANoptosome complexes. In the present review, we highlight the mechanisms underlying mitochondrial dysfunctions and how this key event contributes to inflammatory response as well as cell death modes during CI/RI. Neuroprotective agents targeting mitochondrial dysfunctions may serve as a promising treatment strategy to alleviate serious secondary brain injuries. A comprehensive insight into mitochondrial dysfunctions-mediated PCDs can help provide more effective strategies to guide therapies of CI/RI in IS.

RESUMEN

Introduction: Puerarin (PUE) is a natural compound isolated from Puerariae Lobatae Radix, which has a neuroprotective effect on IS. We explored the therapeutic effect and underlying mechanism of PUE on cerebral I/R injury by inhibiting oxidative stress related to the PI3K/Akt/Nrf2 pathway in vitro and in vivo. Methods: The middle cerebral artery occlusion and reperfusion (MCAO/R) rats and oxygen-glucose deprivation and reperfusion (OGD/R) were selected as the models, respectively. The therapeutic effect of PUE was observed using triphenyl tetrazolium and hematoxylin-eosin staining. Tunel-NeuN staining and Nissl staining to quantify hippocampal apoptosis. The reactive oxygen species (ROS) level was detected by flow cytometry and immunofluorescence. Biochemical method to detect oxidative stress levels. The protein expression related to PI3K/Akt/Nrf2 pathway was detected by using Western blotting. Finally, co-immunoprecipitation was used to study the molecular interaction between Keap1 and Nrf2. Results: In vivo and vitro studies showed that PUE improved neurological deficits in rats, as well as decreased oxidative stress. Immunofluorescence and flow cytometry indicated that the release of ROS can be inhibited by PUE. In addition, the Western blotting results showed that PUE promoted the phosphorylation of PI3K and Akt, and enabled Nrf2 to enter the nucleus, which further activated the expression of downstream antioxidant enzymes such as HO-1. The combination of PUE with PI3K inhibitor LY294002 reversed these results. Finally, co-immunoprecipitation results showed that PUE promoted Nrf2-Keap1 complex dissociation. Discussion: Taken together, PUE can activate Nrf2 via PI3K/Akt and promote downstream antioxidant enzyme expression, which could further ameliorate oxidative stress, against I/R-induced Neuron injury.

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Cerebral ischemia-reperfusion injury (CI/RI) remains the main cause of disability and death in stroke patients due to lack of effective therapeutic strategies. One of the main issues related to CI/RI treatment is the presence of the blood-brain barrier (BBB), which affects the intracerebral delivery of drugs. Ginkgolide B (GB), a major bioactive component in commercially available products of Ginkgo biloba, has been shown significance in CI/RI treatment by regulating inflammatory pathways, oxidative damage, and metabolic disturbance, and seems to be a candidate for stroke recovery. However, limited by its poor hydrophilicity and lipophilicity, the development of GB preparations with good solubility, stability, and the ability to cross the BBB remains a challenge. Herein, we propose a combinatorial strategy by conjugating GB with highly lipophilic docosahexaenoic acid (DHA) to obtain a covalent complex GB-DHA, which can not only enhance the pharmacological effect of GB, but can also be encapsulated in liposomes stably. The amount of finally constructed Lipo@GB-DHA targeting to ischemic hemisphere was validated 2.2 times that of free solution in middle cerebral artery occlusion (MCAO) rats. Compared to the marketed ginkgolide injection, Lipo@GB-DHA significantly reduced infarct volume with better neurobehavioral recovery in MCAO rats after being intravenously administered both at 2 h and 6 h post-reperfusion. Low levels of reactive oxygen species (ROS) and high neuron survival in vitro was maintained via Lipo@GB-DHA treatment, while microglia in the ischemic brain were polarized from the pro-inflammatory M1 phenotype to the tissue-repairing M2 phenotype, which modulate neuroinflammatory and angiogenesis. In addition, Lipo@GB-DHA inhibited neuronal apoptosis via regulating the apoptotic pathway and maintained homeostasis by activating the autophagy pathway. Thus, transforming GB into a lipophilic complex and loading it into liposomes provides a promising nanomedicine strategy with excellent CI/RI therapeutic efficacy and industrialization prospects.

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BACKGROUND: Angiogenesis is an important mechanism of recovery from ischemic stroke. Recent studies have found that there is a close relationship between the VEGF/Notch pathway and angiogenesis. It is unknown whether EA can exert a brain protection effect and promote angiogenesis by acting on the VEGF/Notch signaling pathway after focal cerebral ischemia-reperfusion injury (CIRI). METHODS: The Middle Cerebral Artery occlusion/Reperfusion (MCAo/R) model was established, in which rats were subjected to occlusion with ischemic intervention for 30 min, followed by reperfusion for 8 h, 1 day, 3 days, and 7 days. The first EA treatment was performed 90 min after the animal model was successfully established, and then EA treatments were performed once a day for 7 days. The 2,3,5-triphenyltetrazolium chloride staining and neurological deficit examination were performed to assess the level of CIRI and neuroprotection by EA. Expression levels of VEGFA, Notch1, and Hes1 proteins were measured via western blotting, while the morphological changes of ECs and microvasculature in the cortex were determined using an ultrastructural observation method. RESULTS: EA treatment of PC6, GV26, and SP6 can significantly improve the neurological function of MCAO/R rats, reduce the volume of cerebral infarction, and modulate the ultrastructure of ECs and microvessels in pathological states. Western blotting revealed that EA increased VEGFA protein expression at 8 h and 3 days after CIRI, as well as Notch1 protein expression at 1 and 7 days. Subsequently, EA activated the VEGF/Notch pathway, increasing the expression of the downstream target protein Hes1, reversing EC death, and promoting angiogenesis. CONCLUSION: Our findings showed that EA plays a role in promoting angiogenesis following focal CIRI, and we hypothesized that this was due to the regulation of ECs by the EA-activated VEGF/Notch signaling pathway.

Asunto(s)

Lesiones Encefálicas , Isquemia Encefálica , Electroacupuntura , Daño por Reperfusión , Ratas , Animales , Electroacupuntura/métodos , Ratas Sprague-Dawley , Isquemia Encefálica/terapia , Factor A de Crecimiento Endotelial Vascular , Isquemia , Reperfusión , Daño por Reperfusión/prevención & control , Transducción de Señal , Células Endoteliales/metabolismo , Infarto de la Arteria Cerebral Media/terapia

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BACKGROUND: The role of ferroptosis in ischemic stroke has been hotly debated recently, but the mechanism is not clearly clarified. It has been reported that the NLRP3 inflammasome is essential for the progression of ischemic stroke. Whether the ferroptosis after ischemic stroke mediated by the activation of NLRP3 inflammasome is still not reported. In this study, we investigated the effect of NLRP3 deficiency on ferroptosis following cerebral ischemia-reperfusion injury (CIRI) in vivo and in vitro. MATERIALS: In vivo, we used C57BL/6J mice and NLRP3-/- mice to establish a model of middle cerebral artery occlusion (MCAO). After 3 days of reperfusion, we assessed neurological function and then performed TTC staining to measure the infarct volume. Besides, we measured the expression of NLRP3 inflammasome-related proteins and the ferroptosis-inhibiting protein glutathione peroxidase 4 (GPX4) by western blotting (WB) and immunofluorescence (IF). Moreover, we evaluated the levels of ferroptosis-related factors (Fe2+, MDA and GSH) in the infarct area by using appropriate kits. Furthermore, we used WB to measure the expression of Kelch-like epichlorohydrin-associated protein 1 (Keap1) and nuclear factor erythroid 2-related factor 2 (Nrf2), which participate in the progression of ischemic stroke. In vitro, we knocked down NLRP3 with small interfering RNAs (siRNAs) and established an oxygen glucose deprivation/Reperfusion (OGD/R) model in BV2 cells to simulate ischemic conditions. Next, we assessed the viability of BV2 cells by the Cell Counting Kit (CCK)-8 cytotoxicity assay. Moreover, we used WB to measure the expression of NLRP3, IL-1ß, GPX4, Keap1 and Nrf2 proteins which are involved in CIRI. RESULTS: Three days after MCAO, the NLRP3-/- mice exhibited smaller cerebral infarct volumes and lower neurological deficit scores. The expression of NLRP3 inflammasome-associated proteins (IL-18 and IL-1ß) and Keap1/Nrf2 signaling pathway moleculars (Keap1 and Nrf2) in mice brain tissue and BV2 cells were inhibited by NLRP3 knockout/knockdown, while the expression of GPX4, one of the ferroptosis-related factors was increased. Furthermore, the contents of Fe2+ and MDA in the brain tissues of NLRP3-/- mice were decreased, while the content of GSH were increased significantly. CONCLUSION: Inhibition of the NLRP3 inflammasome alleviates CIRI by inhibiting ferroptosis and inflammation, possibly through a mechanism of the Keap1-Nrf2 pathway.

Asunto(s)

Ferroptosis , Accidente Cerebrovascular Isquémico , Daño por Reperfusión , Animales , Ratones , Ratones Endogámicos C57BL , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Proteína 1 Asociada A ECH Tipo Kelch , Factor 2 Relacionado con NF-E2 , Epiclorhidrina , Infarto

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@#ObjectiveTo explore the protective effect of Sox11 gene on cerebral ischemia reperfusion injury(CIRI)in mice and its mechanism,so as to provide a new target for the treatment of CIRI.MethodsThe mouse middle cerebral artery occlusion(MCAO)model and Neuro2A cell oxygen glucose deprivation reperfusion(OGDR)model were established and detected for the temporal and spatial distribution of Sox11 in the models by real-time quantitative PCR,Western blot,immunohistochemistry(IHC)and immunohistofluorescence(IHF).The altered expression of some crucial genes in the pathway of apoptosis and inflammation in OGDR model after the disruption of Sox11 expression was detected by Western blot.ResultsThe expression level of Sox11 mRNA and protein increased significantly in both MCAO and Neuro2A OGDR models(P = 0.000 1 ～ 0.038 8);After CIRI,Sox11 expression was elevated in the hippocampal dentate gyrus(DG)region of mice;After interfering with the expression of Sox11 in OGDR model,the expression of apoptosis-related protein Cleaved Caspase 3 significantly increased,while the expression of anti-apoptosis protein Bcl-2 significantly decreased,and the expression of phosphorylated NF-κB(p-NF-κB)protein related to inflammatory reaction also up-regulated significantly.Conclusion Sox11gene had a protective effect against CIRI in mice,and was involved in the regulation of apoptosis and inflammation pathways after CIRI.

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Objective:To observe the effects of acupuncture on the expression of circRNA_011989 and circRNA_009775 in the hippocampal tissue of cerebral ischemia/reperfusion injury(CIRI)rats.Methods:CIRI model rats were prepared by the thread bolus method and treated by means of acupuncture(AC).The Garcia score was used to assess the neurological function.TTC staining was used to detect the volume ratio of cerebral infarction.The target prediction website was used to predict the miRNAs and corresponding mRNAs bound by circRNA_011989 and circRNA_009775,and Cytoscape was used to construct the circRNA-miRNA-mRNA co-expression network.The expression of circRNA_011989,circRNA_009775,miR-466b-5p,miR-3065-3p,Rims1,and Slc30a3 in the hippocampal region of the ische-mic side was detected by real time RT-PCR.Results:Compared with CIRI group,Garcia score of rats in CIRI+AC group was significantly increased(P＜0.01),and the infarct volume decreased.The expressions of circRNA_011989,circRNA_009775,Rims1,and Slc30a3 in right hippocampus were up-regulated(P＜0.05,P＜0.01),but the miR-466b-5p and miR-3065-3p were down-regulated(P＜0.05).Conclusion:Acupuncture may significantly ameliorate the neurological deficit symptoms in CIRI rats by upregulating the expression of circRNA_011989 and circRNA_009775,and the specific mechanism may be related to the activation of circRNA_011989/miR-466b-5p/Rim.s1 and circRNA_009775/miR-3065-3p/Slc30a3 axis related.

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Stroke remains one of the leading reasons of mortality and physical disability worldwide. The treatment of cerebral ischemic stroke faces challenges, partly due to a lack of effective treatments. In this study, we demonstrated that autophagy was stimulated by transient middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R). Treatment with (-)-epigallocatechin-3-gallate (EGCG), a bioactive ingredient in green tea, was able to mitigate cerebral ischemia/reperfusion injury (CIRI), given the evidence that EGCG administration could reduce the infarct volume and protect poststroke neuronal loss in MCAO/R mice in vivo and attenuate cell loss in OGD/R-challenged HT22 cells in vitro through suppressing autophagy activity. Mechanistically, EGCG inhibited autophagy via modulating the AKT/AMPK/mTOR phosphorylation pathway both in vivo and in vitro models of stroke, which was further confirmed by the results that the administration of GSK690693, an AKT/AMPK inhibitor, and rapamycin, an inhibitor of mTOR, reversed aforementioned changes in autophagy and AKT/AMPK/mTOR signaling pathway. Overall, the application of EGCG relieved CIRI by suppressing autophagy via the AKT/AMPK/mTOR phosphorylation pathway.

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Background: The incidence of ischemic cerebrovascular disease is increasing in recent years and has been one of the leading causes of neurological dysfunction and death. Ginsenoside Rg1 has been found to protect against neuronal damage in many neurodegenerative diseases. However, the effect and mechanism by which Rg1 protects against cerebral ischemia-reperfusion injury (CIRI) are not fully understood. Here, we report the neuroprotective effects of Rg1 treatment on CIRI and its possible mechanisms in mice. Methods: A bilateral common carotid artery ligation was used to establish a chronic CIRI model in mice. HT22 cells were treated with Rg1 after OGD/R to study its effect on [Ca2+]i. The open-field test and pole-climbing experiment were used to detect behavioral injury. The laser speckle blood flowmeter was used to measure brain blood flow. The Nissl and H&E staining were used to examine the neuronal damage. The Western blotting was used to examine MAP2, PSD95, Tau, p-Tau, NOX2, PLC, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging was used to test the level of [Ca2+]i. Results: Rg1 treatment significantly improved cerebral blood flow, locomotion, and limb coordination, reduced ROS production, increased MAP2 and PSD95 expression, and decreased p-Tau, NOX2, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging results showed that Rg1 could inhibit calcium overload and resist the imbalance of calcium homeostasis after OGD/R in HT22 cells. Conclusion: Rg1 plays a neuroprotective role in attenuating CIRI by inhibiting oxidative stress, calcium overload, and neuroinflammation.

RESUMEN

The study of brain diseases has long been of interest to researchers worldwide, and stroke is the third leading cause of death that threatens human health. At the same time, cerebral ischemia-reperfusion injury is closely associated with high rates of disability and mortality. The conditions of the 6-aminoquinolyl N-hydroxysccinimidyl carbamate method for the derivatization of amino acids in the bone marrow fluid and hippocampus of C57BL/6 mice with cerebral ischemia-reperfusion injury were explored and optimized, such as the column temperature, concentration of derivatization reagents and mobile phase concentration. The mobile phase consisted of 20 mm sodium acetate solution (phosphoric acid to adjust pH 5.0) and 60% acetonitrile solution at a flow rate of 1 ml min-1 . The 23 analytes were separated and determined in a gradient elution procedure; the correlation coefficient r was >0.9990 in the range 0.1-8.0 µg ml-1 . The results showed that the content of relevant analytes was significantly changed in the cerebral ischemia-reperfusion injury model, and the method was suitable for the simultaneous determination of 23 amino acids in the bone marrow fluid and hippocampus of C57BL/6 mice.

Asunto(s)

Médula Ósea , Daño por Reperfusión , Aminoácidos , Aminoquinolinas , Animales , Cromatografía Líquida de Alta Presión/métodos , Hipocampo , Humanos , Indicadores y Reactivos , Ratones , Ratones Endogámicos C57BL

RESUMEN

Ischemic stroke is an acute cerebrovascular disease characterized by sudden interruption of blood flow in a certain part of the brain, leading to serious disability and death. At present, treatment methods for ischemic stroke are limited to thrombolysis or thrombus removal, but the treatment window is very narrow. However, recovery of cerebral blood circulation further causes cerebral ischemia/reperfusion injury (CIRI). The endoplasmic reticulum (ER) plays an important role in protein secretion, membrane protein folding, transportation, and maintenance of intracellular calcium homeostasis. Endoplasmic reticulum stress (ERS) plays a crucial role in cerebral ischemia pathophysiology. Mild ERS helps improve cell tolerance and restore cell homeostasis; however, excessive or long-term ERS causes apoptotic pathway activation. Specifically, the protein kinase R-like endoplasmic reticulum kinase (PERK), activating transcription factor 6 (ATF6), and inositol-requiring enzyme 1 (IRE1) pathways are significantly activated following initiation of the unfolded protein response (UPR). CIRI-induced apoptosis leads to nerve cell death, which ultimately aggravates neurological deficits in patients. Therefore, it is necessary and important to comprehensively explore the mechanism of ERS in CIRI to identify methods for preserving brain cells and neuronal function after ischemia.