Cerebral Ischemia-reperfusion Injury Research Articles

Aquaporins alteration revealed kidney damages in cerebral ischemia/reperfusion rats

BackgroundRestoration of blood supply is a desired goal for the treatment of acute ischemic stroke. However, the restoration often leads to cerebral ischemia-reperfusion injury (CIR/I), which greatly increases the risk of non-neural organ damage. In particular, the acute kidney injury might be one of the most common complications. AimsThe study aimed to understand the damage occurred and the potential molecular mechanisms. MethodsThe study was explored on the CIR/I rats generated by performing middle cerebral artery occlusion/reperfusion (MCAO/Reperfusion). The rats were evaluated with injury on the brains, followed by the non-neural organs including kidneys, livers, colons and stomachs. They were examined further with histopathological changes, and gene expression alterations by using RT-qPCR of ten aquaporins (Aqps) subtypes including Aqp1～Aqp9 and Aqp11. Furthermore, the Aqps expression profiles were constructed for each organ and analyzed by performing Principle Component Analysis. In addition, immunohistochemistry was explored to look at the protein expression of Aqp1, Aqp2, Aqp3 and Aqp4 in the rat kidneys. ResultsThere was a prominent down-regulation profile in the MCAO/Reperfusion rat kidneys. The protein expression of Aqp1, Aqp2, Aqp3 and Aqp4 was decreased in the kidneys of the MCAO/Reperfusion rats. We suggested that the kidney was in the highest risk to be damaged following the CIR/I. Down-regulation of Aqp2, Aqp3 and Aqp4 was involved in the acute kidney injury induced by the CIR/I.

Utilizing network pharmacology, molecular docking, and animal models to explore the therapeutic potential of the WenYang FuYuan recipe for cerebral ischemia-reperfusion injury through AGE-RAGE and NF-κB/p38MAPK signaling pathway modulation

BackgroundStroke is a debilitating condition with high morbidity, disability, and mortality that significantly affects the quality of life of patients. In China, the WenYang FuYuan recipe is widely used to treat ischemic stroke. However, the underlying mechanism remains unknown, so exploring the potential mechanism of action of this formula is of great practical significance for stroke treatment. ObjectiveThis study employed network pharmacology, molecular docking, and in vivo experiments to clarify the active ingredients, potential targets, and molecular mechanisms of the WenYang FuYuan recipe in cerebral ischemia-reperfusion injury, with a view to providing a solid scientific foundation for the subsequent study of this recipe. Materials and methodsActive ingredients of the WenYang FuYuan recipe were screened using the traditional Chinese medicine systems pharmacology database and analysis platform. Network pharmacology approaches were used to explore the potential targets and mechanisms of action of the WenYang FuYuan recipe for the treatment of cerebral ischemia-reperfusion injury. The Middle Cerebral Artery Occlusion/Reperfusion 2 h Sprague Dawley rat model was prepared, and TTC staining and modified neurological severity score were applied to examine the neurological deficits in rats. HE staining and Nissl staining were applied to examine the pathological changes in rats. Immunofluorescence labeling and Elisa assay were applied to examine the expression levels of certain proteins and associated factors, while qRT-PCR and Western blotting were applied to examine the expression levels of linked proteins and mRNAs in disease-related signaling pathways. ResultsWe identified 62 key active ingredients in the WenYang FuYuan recipe, with 222 highly significant I/R targets, forming 138 pairs of medication components and component-targets, with the top five being Quercetin, Kaempferol, Luteolin, β-sitosterol, and Stigmasterol. The key targets included TP53, RELA, TNF, STAT1, and MAPK14 (p38MAPK). Targets related to cerebral ischemia-reperfusion injury were enriched in chemical responses, enzyme binding, endomembrane system, while enriched pathways included lipid and atherosclerosis, fluid shear stress and atherosclerosis, AGE-RAGE signaling in diabetic complications. In addition, the main five active ingredients and targets in the WenYang FuYuan recipe showed high binding affinity (e.g. Stigmasterol and MAPK14, total energy <−10.5 Kcal/mol). In animal experiments, the WenYang FuYuan recipe reduced brain tissue damage, increased the number of surviving neurons, and down-regulated S100β and RAGE protein expression. Moreover, the relative expression levels of key targets such as TP53, RELA and p38MAPK mRNA were significantly down-regulated in the WenYang FuYuan recipe group, and serum IL-6 and TNF-a factor levels were reduced. After WenYang FuYuan recipe treatment, the AGE-RAGE signaling pathway and downstream NF-kB/p38MAPK signaling pathway-related proteins were significantly modulated. ConclusionThis study utilized network pharmacology, molecular docking, and animal experiments to identify the potential mechanism of the WenYang FuYuan recipe, which may be associated with the regulation of the AGE-RAGE signaling pathway and the inhibition of target proteins and mRNAs in the downstream NF-kB/p38MAPK pathway.

Tongqiao Huoxue Decoction inhibits ferroptosis by facilitating ACSL4 ubiquitination degradation for neuroprotection against cerebral ischemia-reperfusion injury

BackgroundCerebral ischemia-reperfusion injury (CIRI) refers to brain tissue injury caused by the temporary interruption of cerebral blood flow ischemia followed by the restoration of reperfusion, which is the main cause of post-stroke brain injury. A traditional Chinese herbal preparation called Tongqiao Huoxue Decoction (TQHX) has shown promise in reducing CIRI in rats. However, the mechanism of this herbal preparation for CIRI remains unclear. PurposeThis study aimed to evaluate the therapeutic effect of TQHX extract on rats with CIRI and to further explore the underlying mechanisms. MethodsThe active ingredients of TQHX extract were quantified by the high-performance liquid chromatography (HPLC) condition. We conducted thorough investigations to assess the effects of TQHX on CIRI and ferroptosis using oxygen-glucose deprivation/reperfusion (OGD/R)-treated PC12 cells as an in vitro model and transient middle cerebral artery occlusion (tMCAO) animals as an in vivo model. The neurological score assessment was performed to evaluate the neuroprotective effects of TQHX extract on tMCAO rats. Using histologic methods to study the extent of cerebral infarction, blood-brain barrier, and rat brain tissue. We examined the impact of TQHX on ferroptosis-related markers of Fe2+, superoxide dismutase (SOD), reactive oxygen species (ROS), and malondialdehyde (MDA) in the brain tissue. In addition, the expression of key proteins and markers of ferroptosis, as well as key factors associated with Acyl-CoA synthetase long-chain family member 4 (ACSL4) were detected by Western blot and quantitative real-time PCR (RT-qPCR). ResultsTQHX extract could decrease the Longa score and extent of cerebral infarction of tMCAO rats, which exerted the function of neuroprotection. Additionally, TQHX treatment efficiently decreased levels of MDA and ROS while increasing the expression of SOD and ferroptosis-related proteins including ferritin heavy chain 1 (FTH1) and glutathione peroxidase 4 (GPX4) at the transcription and translation level. Meanwhile, TQHX provided strong protection against oxidative stress and ferritin accumulation by increasing the ubiquitination and degradation of ACSL4. The injection of OE-ACSL4 reversed the effects of TQHX on neuroprotection and ferroptosis inhibition in PC12 cells. The injection of shACSL4 reversely validate the crucial role of ACSL4 in CIRI rat treatment. ConclusionThis work shows that TQHX promotes the ubiquitination-mediated degradation of ACSL4, which improves oxidative stress and inhibits the beginning of ferroptosis in cells. TQHX provides a possible path for additional research in CIRI therapies, advancing translational investigations.

Naodesheng Pills Ameliorate Cerebral Ischemia Reperfusion-Induced Ferroptosis via Inhibition of the ERK1/2 Signaling Pathway.

Ferroptosis plays a crucial role in the occurrence and development of cerebral ischemia-reperfusion (I/R) injury and is regulated by mitogen-activated protein kinase 1/2 (ERK1/2). In China, Naodesheng Pills (NDSP) are prescribed to prevent and treat cerebrosclerosis and stroke. However, the protective effects and mechanism of action of NDSP against cerebral I/R-induced ferroptosis remain unclear. We investigated whether NDSP exerts its protective effects against I/R injury by regulating ferroptosis and aimed to elucidate the underlying mechanisms. The efficacy of NDSP was evaluated using a Sprague-Dawley rat model of middle cerebral artery occlusion and an in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) model. Brain injury was assessed using 2,3,5-triphenyltetrazolium chloride (TTC), hematoxylin and eosin staining, Nissl staining, and neurological scoring. Western blotting was performed to determine the expression levels of glutathione peroxidase 4 (GPX4), divalent metal-ion transporter-1 (DMT1), solute carrier family 7 member 11 (SLC7A11), and transferrin receptor 1 (TFR1). Iron levels, oxidative stress, and mitochondrial morphology were also evaluated. Network pharmacology was used to assess the associated mechanisms. NDSP (1.08 g/kg) significantly improved cerebral infarct area, cerebral water content, neurological scores, and cerebral tissue damage. Furthermore, NDSP inhibited I/R- and OGD/R-induced ferroptosis, as evidenced by the increased protein expression of GPX4 and SLC7A11, suppression of TFR1 and DMT1, and an overall reduction in oxidative stress and Fe2+ levels. The protective effects of NDSP in vitro were abolished by the GPX4 inhibitor RSL3. Network pharmacology analysis revealed that ERK1/2 was the core target gene and that NDSP reduced the amount of phosphorylated ERK1/2. NDSP exerts its protective effects against I/R by inhibiting cerebral I/R-induced ferroptosis, and this mechanism is associated with the regulation of ferroptosis via the ERK1/2 signaling pathway.

L-DOPA ameliorates hippocampus-based mitochondria respiratory dysfunction caused by GCI/R injury

Mitochondrial dysmorphology/dysfunction follow global cerebral ischemia-reperfusion (GCI/R) injury, leading to neuronal death. Our previous researches demonstrated that Levodopa (L-DOPA) improves learning and memory impairment in GCI/R rats by increasing synaptic plasticity of hippocampal neurons. This study investigates if L-DOPA, used in Parkinson's disease treatment, alleviates GCI/R-induced cell death by enhancing mitochondrial quality. Metabolomics and transcriptomic results showed that GCI/R damage affected the Tricarboxylic acid (TCA) cycle in the hippocampus. The results of this study show that L-DOPA stabilized mitochondrial membrane potential and ultrastructure in hippocampus of GCI/R rats, increased dopamine level in hippocampus, decreased succinic acid level, and stabilized Ca2+ level in CA1 subregion of hippocampus. As a precursor of dopamine, L-DOPA is presumed to improves mitochondrial function in hippocampus of GCI/R rats. However, dopamine cannot cross the blood-brain barrier, so L-DOPA is used in clinical therapy to supplement dopamine. In this investigation, OGD/R models were established in isolated mouse hippocampal neurons (HT22) and primary rat hippocampal neurons. Notably, dopamine exhibited a multifaceted impact, demonstrating inhibition of mitochondrial reactive oxygen species (mitoROS) production, stabilization of mitochondrial membrane potential and Ca2+ level, facilitation of TCA circulation, promotion of aerobic respiratory metabolism, and downregulation of succinic acid-related gene expression. Consistency between in vitro and in vivo results underscores dopamine's significant neuroprotective role in mitigating mitochondrial dysfunction following global cerebral hypoxia and ischemia injury. Supplement dopamine may represent a promising therapy to the cognitive impairment caused by GCI/R injury.

Electroacupuncture pretreatment alleviates rats cerebral ischemia-reperfusion injury by inhibiting ferroptosis

ObjectiveTo explore the preventive effect of electroacupuncture pretreatment on stroke in rats by inhibiting ferroptosis and oxidative stress. MethodsRats were randomly assigned to the sham, middle cerebral artery occlusion/reperfusion (MCAO/R), MCAO/R + EP, MCAO/R + EP + erastin, and MCAO/R + EP + ferrostatin 1 groups. Daily electroacupuncture was performed 2 weeks before establishing the MCAO/R model utilizing the modified Zea Longa suture method. Rats were sacrificed 1 day after reperfusion, and brain tissues were collected. They were prepared for hematoxylin and eosin staining, prussian blue staining, transmission electron microscope. Measurement of total iron levels using a commercial kit, detection of malondialdehyde (MDA) and superoxide dismutase (SOD) levels by ELISA, and examination of 15-lox2, GPX4, SLC7A11, ACSL4, and TFR1 by western blotting. ResultsCompared with sham rats, cerebral infarction size was dramatically larger in MCAO/R rats. Moreover, the MCAO/R group displayed damaged mitochondria with a disarranged structure of cristae; free iron, total iron levels, and oxidative stress were significantly higher. Cerebral pathological lesions, oxidative stress, total iron levels, and protein levels of ACSL4, TFR1, and 15-lox2 were significantly reduced in the MCAO/R + EP and MCAO/R + EP + ferrostatin 1 groups, while the protective effect of electroacupuncture pretreatment on cerebral ischemia-reperfusion injury was inhibited by treatment with the ferroptosis activator erastin. ConclusionElectroacupuncture pretreatment can protect rats from cerebral ischemia-reperfusion injury by reducing the area of cerebral infarction and inhibiting ferroptosis and oxidative stress.

Integrated pharmacokinetic-pharmacodynamic modeling and metabolomic research on polyphenol-rich fraction of Thymus quinquecostatus Celak. Alleviating cerebral ischemia-reperfusion injury

Ethnopharmacological relevanceThymus quinquecostatus Celak., a member of thymus genus in Lamiaceae family, has been used as a folk medicine for relieving exterior syndrome and alleviating pain in China. The polyphenol-rich fraction (PRF) derived from Thymus quinquecostatus Celak. had been validated that it can protect cerebral ischemia-reperfusion injury (CIRI) by activating Keap1/Nrf2/HO-1 signaling pathway.Aim of this study: To explore effective components and their pharmacokinetic and pharmacodynamic characteristics as well as possible mechanisms of PRF in treating CIRI. Materials and methodsNormal treated group (NTG) and tMCAO model treated group (MTG) rats were administrated PRF intragastrically. The prototype components and metabolites of PRF in plasma and brain were analyzed by the UPLC-Q-Exactive Orbitrap MSn method. Subsequently, the pharmacokinetics properties of indicative components were performed based on HPLC-QQQ-MS/MS. SOD and LDH activities were determined to study the pharmacodynamic (PD) properties of PRF. The PK-PD relationship of PRF was constructed. In addition, the effect of PRF on endogenous metabolites in plasma and brain was investigated using metabolomic method. ResultsSalvianic acid A, caffeic acid, rosmarinic acid, scutellarin, and apigenin-7-O-glucuronide were selected as indicative components based on metabolic analysis. The non-compartmental parameters were calculated for indicative components in plasma and brain of NTG and MTG rats. Furthermore, single-component and multi-component PK-PD modeling involved Emax, Imax PD models for effect indexes were fitted as well as ANN models were established, which indicated that these components can work together to regulate SOD and LDH activities in plasma and SOD activity in brain tissue to improve CIRI. Additionally, PRF may ameliorate CIRI by regulating the disorder of endogenous metabolites in lipid metabolism, amino acid metabolism, and purine metabolism pathways in vivo, among which lipid metabolism and purine metabolism are closely related to oxidative stress. ConclusionThe PK-PD properties of effect substances and mechanisms of PRF anti-CIRI were further elaborated. The findings provide a convincing foundation for the application of T. quinquecostatus Celak. in the maintenance of human health disorders.

Mechanism of ameliorating cerebral ischemia/reperfusion injury by antioxidant inhibition of autophagy based on network pharmacology and experimental verification.

Cerebral ischemia-reperfusion injury (CIRI) is one of the most difficult challenges in cerebrovascular disease research. It is primarily caused by excessive autophagy induced by oxidative stress. Previously, a novel compound X5 was found, and the excellent antioxidant activity of it was verified in this study. Moreover, network pharmacological analysis suggested that compound X5 was closely associated with autophagy and the mTOR pathway. In vitro, X5 could significantly inhibit the expression of autophagy proteins Beclin-1 and LC3-β, which are induced by H2O2, and promote the expression of SIRT1. In vivo, compound X5 significantly reduced the infarct size and improved the neurological function scores in the middle cerebral artery occlusion (MCAO) model of rats. In conclusion, ROS-induced autophagy is closely related to mTOR, SIRT1 and others, and X5 holds promise as a candidate for the treatment of CIRI.

Exploring the mechanism of acupuncture and moxibustion in the treatment of cerebral ischemia-reperfusion injury based on network pharmacology

Objective To explore the potential mechanism of acupuncture and moxibustion in the treatment of cerebral ischemia reperfusion injury (CIRI) using network pharmacology. Methods Firstly, the potential targets of acupuncture and moxibustion for CIRI were screened from the GEO database, and then the disease targets of CIRI were screened through data cleaning. Finally, the intersection between the disease targets of acupuncture and moxibustion for CIRI and the disease targets of CIRI were obtained, so as to obtain the key targets of acupuncture and moxibustion for CIRI. The Gene Ontology (GO) and The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed on these key targets. Results A total of 18804 potential CIRI targets, 370 CIRI disease targets and 152 key targets were obtained. GO and KEGG enrichment analysis of the key targets were performed to obtain the most significantly enriched GO entries and key pathways of the targets in cellular components, molecular functions and biological processes. Conclusion Acupuncture and moxibustion may treat CIRI by regulating calcium ion transport, postsynaptic organization and circadian entrainment.

NIR-II nanoprobes for investigating the glymphatic system function under anesthesia and stroke injury

The glymphatic system plays an important role in the transportation of cerebrospinal fluid (CSF) and the clearance of metabolite waste in brain. However, current imaging modalities for studying the glymphatic system are limited. Herein, we apply NIR-II nanoprobes with non-invasive and high-contrast advantages to comprehensively explore the function of glymphatic system in mice under anesthesia and cerebral ischemia–reperfusion injury conditions. Our results show that the supplement drug dexmedetomidine (Dex) enhances CSF influx in the brain, decreases its outflow to mandibular lymph nodes, and leads to significant differences in CSF accumulation pattern in the spine compared to isoflurane (ISO) alone, while both ISO and Dex do not affect the clearance of tracer-filled CSF into blood circulation. Notably, we confirm the compromised glymphatic function after cerebral ischemia–reperfusion injury, leading to impaired glymphatic influx and reduced glymphatic efflux. This technique has great potential to elucidate the underlying mechanisms between the glymphatic system and central nervous system diseases.Graphical

Retraction: Reduced levels of A20 protein prompted RIPK1-dependent apoptosis and blood-brain barrier breakdown during cerebral ischemia reperfusion injury.

Retraction: Reduced levels of A20 protein prompted RIPK1-dependent apoptosis and blood-brain barrier breakdown during cerebral ischemia reperfusion injury.

Voacangine mitigates oxidative stress and neuroinflammation in middle cerebral artery occlusion-induced cerebral ischemia/reperfusion injury by averting the NF-κBp65/MAPK signaling pathways in rats.

Ischemic stroke is a leading cause of human mortality. Cerebral ischemia-reperfusion injury (CI/RI) is a primary cause of stroke. Ischemia-reperfusion (I/R) resulting in oxidative stress and inflammatory events may lead to severe neuronal impairments. Thus, anti-oxidative and anti-inflammatory mediators that can alleviate post-I/R neuronal injuries are required for the treatment of CI/RI. An alkaloid, voacangine (VCG) is a recognized antioxidant, anti-inflammatory, and anticancer agent. Hence, the current study intended to explore the neuroprotective potential and the principal mechanisms of VCG in CI/RI. The experimental rats were divided into four sets: control, I/R-induced, I/R + VCG (2.5 mg/kg), I/R + VCG (5 mg/kg). CI/RI was induced by implanting a thread into the middle cerebral artery occlusion (MCAO) model. Brain damages were assessed on the basis of brain edema, brain infarct volume, neurological deficit score, histopathology, oxidative stress, and neuroinflammation. Results revealed that VCG inhibited the triggering of NLRP3 inflammasome, pro-inflammatory cytokines, lipid peroxidation, but enhanced the antioxidant status in MCAO rats. Furthermore, VCG treatment averted brain damage by I/R, neuroinflammation, and oxidative stress by suppressing NF-κBp65/MAPK pathways. The results of the study provide pertinent insights pertaining to the role of VCG as a potential neuroprotective agent against ischemic stroke.

The protective effect and mechanism of glycosides of cistanche deserticola on rats in middle cerebral artery occlusion (MCAO) model

ABSTRACT Cerebral ischemia-reperfusion injury (CIRI) occurs frequently clinically as a complication following cardiovascular resuscitation resulting in neuronal damage specifically to the hippocampal CA1 region with consequent cognitive impairment. Apoptosis and oxidative stress were proposed as major risk factors associated with CIRI development. Previously, glycosides obtained from Cistanche deserticola (CGs) were shown to play a key role in counteracting CIRI; however, the underlying mechanisms remain to be determined. This study aimed to investigate the neuroprotective effect of CGs on subsequent CIRI in rats. The model of CIRI was established for 2 hr and reperfusion for 24 hr by middle cerebral artery occlusion (MCAO) model. The MCAO rats were used to measure the antioxidant and anti-apoptotic effects of CGs on CIRI. Neurological function was evaluated by the Longa neurological function score test. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to detect the area of cerebral infarction. Nissl staining was employed to observe neuronal morphology. TUNEL staining was used to detect neuronal apoptosis, while Western blot determined protein expression levels of factors for apoptosis-related and PI3K/AKT/Nrf2 signaling pathway. Data demonstrated that CGs treatment improved behavioral performance, brain injury, and enhanced antioxidant and anti-apoptosis in CIRI rats. In addition, CGs induced activation of PI3K/AKT/Nrf2 signaling pathway accompanied by inhibition of the expression of apoptosis-related factors. Evidence indicates that CGs amelioration of CIRI involves activation of the PI3K/AKT/Nrf2 signaling pathway associated with increased cellular viability suggesting these glycosides may be considered as an alternative compound for CIRI treatment.

4′-O-methylbavachalcone alleviates ischemic stroke injury by inhibiting parthanatos and promoting SIRT3

Cerebral ischemia-reperfusion injury (CIRI) can induce massive death of ischemic penumbra neurons via oxygen burst, exacerbating brain damage. Parthanatos is a form of caspase-independent cell death involving excessive activation of PARP-1, closely associated with intense oxidative stress following CIRI. 4′-O-methylbavachalcone (MeBavaC), an isoprenylated chalcone component in Fructus Psoraleae, has potential neuroprotective effects. This study primarily investigates whether MeBavaC can act on SIRT3 to alleviate parthanatos of ischemic penumbra neurons induced by CIRI. MeBavaC was oral gavaged to the middle cerebral artery occlusion-reperfusion (MCAO/R) rats after occlusion. The effects of MeBavaC on cerebral injury were detected by the neurological deficit score and cerebral infarct volume. In vitro, PC-12 cells were subjected to oxygen and glucose deprivation/reoxygenation (OGD/R), and assessed cell viability and cell injury. Also, the levels of ROS, mitochondrial membrane potential (MMP), and intracellular Ca2+ levels were detected to reflect mitochondrial function. We conducted western blotting analyses of proteins involved in parthanatos and related signaling pathways. Finally, the exact mechanism between the neuroprotection of MeBavaC and parthanatos was explored. Our results indicate that MeBavaC reduces the cerebral infarct volume and neurological deficit scores in MCAO/R rats, and inhibits the decreased viability of PC-12 cells induced by OGD/R. MeBavaC also downregulates the expression of parthanatos-related death proteins PARP-1, PAR, and AIF. However, this inhibitory effect is weakened after the use of a SIRT3 inhibitor. In conclusion, the protective effect of MeBavaC against CIRI may be achieved by inhibiting parthanatos of ischemic penumbra neurons through the SIRT3-PARP-1 axis.

Dietary Supplementation with Nervonic Acid Ameliorates Cerebral Ischemia-Reperfusion Injury by Modulating of Gut Microbiota Composition-Fecal Metabolites Interaction.

Cerebral ischemia-reperfusion (IR) injury stands as a prominent global contributor to disability and mortality. Nervonic acid (NA), a bioactive elongated monounsaturated fatty acid, holds pivotal significance in human physiological well-being. This research aims to explore the prophylactic effects and fundamental mechanisms of NA in a rat model of cerebral IR injury. Through the induction of middle cerebral artery occlusion, this study establishes a rat model of cerebral IR injury and comprehensively assesses the pharmacodynamic impacts of NA pretreatment. This evaluation involves behavioral analyses, histopathological examinations, and quantification of serum markers. Detailed mechanisms of nervonic acid's prophylactic effects are revealed through fecal metabolomics and 16S rRNA sequencing analyses. Our findings robustly support nervonic acid's capacity to ameliorate neurological impairments in rats afflicted with cerebral IR injury. Beyond its neurological benefits, NA demonstrates its potential by rectifying metabolic perturbations across diverse pathways, particularly those pertinent to unsaturated fatty acid metabolism. Additionally, NA emerges as a modulator of gut microbiota composition, notably by selectively enhancing vital genera like Lactobacillus. These comprehensive findings highlight the potential of incorporating NA as a functional component in dietary interventions aimed at targeting cerebral IR injury.

Astragaloside IV combined with ligustrazine ameliorates abnormal mitochondrial dynamics via Drp1 SUMO/deSUMOylation in cerebral ischemia-reperfusion injury.

Astragaloside IV (AST IV) and ligustrazine (Lig), the main ingredients of Astragali Radix and Chuanxiong Rhizoma respectively, have demonstrated significant benefits in treatment of cerebral ischemia -reperfusion injury (CIRI); however, the mechanisms underlying its benificial effects remain unclear. SUMO-1ylation and deSUMO-2/3ylation of dynamin-related protein 1 (Drp1) results in mitochondrial homeostasis imbalance following CIRI, which subsequently aggravates cell damage. This study investigates the mechanisms by which AST IV combined with Lig protects against CIRI, focusing on the involvement of SUMOylation in mitochondrial dynamics. Rats were administrated AST IV and Lig for 7 days, and middle cerebral artery occlusion was established to mimic CIRI. Neural function, cerebral infarction volume, cerebral blood flow, cognitive function, cortical pathological lesions, and mitochondrial morphology were measured. SH-SY5Y cells were subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) injury. Mitochondrial membrane potential and lactic dehydrogenase (LDH), reactive oxygen species (ROS), and adenosine triphosphate (ATP) levels were assessed with commercial kits. Moreover, co-immunoprecipitation (Co-IP) was used to detect the binding of SUMO1 and SUMO2/3 to Drp1. The protein expressions of Drp1, Fis1, MFF, OPA1, Mfn1, Mfn2, SUMO1, SUMO2/3, SENP1, SENP2, SENP3, SENP5, and SENP6 were measured using western blot. In rats with CIRI, AST IV and Lig improved neurological and cognitive functions, restored CBF, reduced brain infarct volume, and alleviated cortical neuron and mitochondrial damage. Moreover, in SH-SY5Y cells, the combination of AST IV and Lig enhanced cellular viability, decreased release of LDH and ROS, increased ATP content, and improved mitochondrial membrane potential. Furthermore, AST IV combined with Lig reduced the binding of Drp1 with SUMO1, increased the binding of Drp1 with SUMO2/3, suppressed the expressions of Drp1, Fis1, MFF, and SENP3, and increased the expressions of OPA1, Mfn1, Mfn2, SENP1, SENP2, and SENP5. SUMO1 overexpression promoted mitochondrial fission and inhibited mitochondrial fusion, whereas SUMO2/3 overexpression suppressed mitochondrial fission. AST IV combined with Lig could reverse the effects of SUMO1 overexpression while enhancing those of SUMO2/3 overexpression. This study posits that the combination of AST IV and Lig has the potential to reduce the SUMO-1ylation of Drp1, augment the SUMO-2/3ylation of Drp1, and thereby exert a protective effect against CIRI.

Research progress on the role of astrocytes in cerebral ischemia/reperfusion injury

The pathophysiological mechanism of cerebral ischemia/reperfusion injury (CIRI) is complex, and the current treatment methods are limited and the efficacy is not good. Previous therapeutic strategies of CIRI mostly target neurons, but no significant progress has been made. At present, astrocytes are expected to be promising effector cells for the treatment of CIRI. Astrocytes are a "double-edged sword" in the pathological process of CIRI, with both neurotoxic and neuroprotective effects on the central nervous system. How to effectively use astrocytes to treat CIRI has become a research hotspot. In this review, the dual roles of astrocytes in CIRI mechanism were reviewed, and the related mechanisms of astrocytes in relieving oxidative stress induced by CIRI were emphasized, in order to provide new ideas for the treatment of CIRI.

Mechanism of acupuncture in attenuating cerebral ischaemia-reperfusion injury based on nuclear receptor coactivator 4 mediated ferritinophagy.

To explore the effect of acupuncture treatment on cerebral ischaemia-reperfusion injury (CIRI) and reveal the underlying mechanism of the effect based on nuclear receptor coactivator 4 (NCOA4) mediated ferritinophagy. Sprague-Dawley male rats were divided into four groups: the sham group, model group, acupuncture group, and sham acupuncture group. After 2 h of middle cerebral artery occlusion (MCAO), reperfusion was performed for 24 h to induce CIRI. The rats were treated with acupuncture at the Neiguan (PC6) and Shuigou (GV26) acupoints. Their neurological function was evaluated by taking their Bederson scores at 2 h after ischaemia and 24 h after reperfusion. Triphenyltetrazolium chloride staining was applied to assess the cerebral infarct volume at 24 h after reperfusion. The malondialdehyde (MDA) and ferrous iron (Fe2+) levels were observed after 24 h of reperfusion using an assay kit. Western blotting was performed to detect the expression of NCOA4 and ferritin heavy chain 1 (FTH1) at 24 h after reperfusion. Moreover, the colocalization of ferritin with neurons, NCOA4 with microtubule-associated protein 1 light chain 3 (LC3), and NCOA4 with ferritin was visualized using immunofluorescence staining. Acupuncture significantly improved neurological function and decreased cerebral infarct volume in the acupuncture group. Following CIRI, the expression of NCOA4, LC3 and FTH1 was increased, which enhanced ferritinophagy and induced an inappropriate accumulation of Fe2+ and MDA in the ischaemic brain. However, acupuncture dramatically downregulated the expression of NCOA4, LC3 and FTH1, inhibited the overactivation of ferritinophagy, and decreased the levels of MDA and Fe2+. Acupuncture can inhibit NCOA4-mediated ferritinophagy and protect neurons against CIRI in a rat model.

The protective effects of methylene blue on astrocytic swelling after cerebral ischemia-reperfusion injuries are mediated by Aquaporin-4 and metabotropic glutamate receptor 5 activation

Methylene blue (MB) was found to exert neuroprotective effect on different brain diseases, such as ischemic stroke. This study assessed the MB effects on ischemia induced brain edema and its role in the inhibition of aquaporin 4 (AQP4) and metabotropic glutamate receptor 5 (mGluR5) expression. Rats were exposed 1 h transient middle cerebral artery occlusion (tMCAO), and MB was injected intravenously following reperfusion (3 mg/kg). Magnetic resonance imaging (MRI) and 2,3,5-triphenyltetrazolium chloride (TTC) staining was performed 48 h after the onset of tMCAO to evaluate the brain infarction and edema. Brain tissues injuries as well as the glial fibrillary acidic protein (GFAP), AQP4 and mGluR5 expressions were detected. Oxygen and glucose deprivation/reoxygenation (OGD/R) was performed on primary astrocytes (ASTs) to induce cell swelling. MB was administered at the beginning of reoxygenation, and the perimeter of ASTs was measured by GFAP immunofluorescent staining. 3,5-dihydroxyphenylglycine (DHPG) and fenobam were given at 24 h before OGD to examine their effects on MB functions on AST swelling and AQP4 expression. MB remarkably decreased the volumes of T2WI and ADC lesions, as well as the cerebral swelling. Consistently, MB treatment significantly decreased GFAP, mGluR5 and AQP4 expression at 48 h after stroke. In the cultivated primary ASTs, OGD/R and DHPG significantly increased ASTs volume as well as AQP4 expression, which was reversed by MB and fenobam treatment. The obtained results highlight that MB decreases the post-ischemic brain swelling by regulating the activation of AQP4 and mGluR5, suggesting potential applications of MB on clinical ischemic stroke treatment.

Mitochondria-associated endoplasmic reticulum membranes tethering protein VAPB-PTPIP51 protects against ischemic stroke through inhibiting the activation of autophagy.

Mitochondria-associated endoplasmic reticulum membranes (MAMs) serve as a crucial bridge connecting the endoplasmic reticulum (ER) and mitochondria within cells. Vesicle-associated membrane protein-associated protein B (VAPB) and protein tyrosine phosphatase interacting protein 51 (PTPIP51) are responsible for the formation and stability of MAMs, which have been implicated in the pathogenesis of various diseases. However, the role of MAMs in ischemic stroke (IS) remains unclear. We aimed to investigate the role of MAMs tethering protein VAPB-PTPIP51 in experimental cerebral ischemia. We simulated cerebral ischemia-reperfusion injury (CIRI) by using a mouse middle cerebral artery occlusion (MCAO) model. We observed a decrease in VAPB-PTPIP51 expression in the brain tissue. Our findings suggested compromised MAMs after MCAO, as a decreased mitochondria-ER contact (MERC) coverage and an increased distance were observed through the transmission electron microscope (TEM). Upon VAPB or PTPIP51 knockdown, the damage to MAMs was exacerbated, accompanied by excessive autophagy activation and increased reactive oxygen species (ROS) production, resulting in an enlarged infarct area and exacerbated neurological deficits. Notably, we observed that this damage was concomitant with the inhibition of the PI3K/AKT/mTOR pathway and was successfully mitigated by the treatment with the PI3K activator. Our findings suggest that the downregulation of VAPB-PTPIP51 expression after IS mediates structural damage to MAMs. This may exacerbate CIRI by inhibiting the PI3K pathway and activating autophagy, thus providing new therapeutic targets for IS.