Disulfiram downregulates ferredoxin 1 to maintain copper homeostasis and inhibit inflammation in cerebral ischemia/reperfusion injury.

In the current study, we aimed to investigate whether disulfiram (DSF) exerts a neuroprotective role in cerebral ischemiareperfusion (CI-RI) injury by modulating ferredoxin 1 (FDX1) to regulate copper ion (Cu) levels and inhibiting inflammatory responses. To simulate CI-RI, a transient middle cerebral artery occlusion (tMCAO) model in C57/BL6 mice was employed. Mice were administered with or without DSF before and after tMCAO. Changes in infarct volume after tMCAO were observed using TTC staining. Nissl staining and hematoxylin-eosin (he) staining were used to observe the morphological changes of nerve cells at the microscopic level. The inhibitory effect of DSF on initial inflammation was verified by TUNEL assay, apoptosis-related protein detection and iron concentration detection. FDX1 is the main regulatory protein of copper death, and the occurrence of copper death will lead to the increase of HSP70 stress and inflammatory response. Cuproptosis-related proteins and downstream inflammatory factors were detected by western blotting, immunofluorescence staining, and immunohistochemistry. The content of copper ions was detected using a specific kit, while electron microscopy was employed to examine mitochondrial changes. We found that DSF reduced the cerebral infarction volume, regulated the expression of cuproptosis-related proteins, and modulated copper content through down regulation of FDX1 expression. Moreover, DSF inhibited the HSP70/TLR-4/NLRP3 signaling pathway. Collectively, DSF could regulate Cu homeostasis by inhibiting FDX1, acting on the HSP70/TLR4/NLRP3 pathway to alleviate CI/RI. Accordingly, DSF could mitigate inflammatory responses and safeguard mitochondrial integrity, yielding novel therapeutic targets and mechanisms for the clinical management of ischemia-reperfusion injury.

RNA sequencing reveals the potential mechanism of exercise preconditioning for cerebral ischemia reperfusion injury in rats.

INTRODUCTION: Cerebral ischemia reperfusion injury (CIRI) often leads to deleterious complications after stroke patients receive reperfusion therapy. Exercise preconditioning (EP) has been reported to facilitate brain function recovery. We aim to explore the specific mechanism of EP in CIRI. METHODS: Sprague-Dawley rats were randomized into Sham, middle cerebral artery occlusion (MCAO), and EP groups (n = 11). The rats in the EP group received adaptive training for 3 days (10 m/min, 20 min/day, with a 0° incline) and formal training for 3 weeks (6 days/week, 25 m/min, 30 min/day, with a 0° incline). Then, rats underwent MCAO surgery to establish CIRI models. After 48 h, neurological deficits and cerebral infarction of the rats were measured. Neuronal death and apoptosis in the cerebral cortices were detected. Furthermore, RNA sequencing was conducted to investigate the specific mechanism of EP on CIRI, and qPCR and Western blotting were further applied to confirm RNA sequencing results. RESULTS: EP improved neurological deficit scores and reduced cerebral infarction in MCAO rats. Additionally, pre-ischemic exercise also alleviated neuronal death and apoptosis of the cerebral cortices in MCAO rats. Importantly, 17 differentially expressed genes (DEGs) were identified through RNA sequencing, and these DEGs were mainly enriched in the HIF-1 pathway, cellular senescence, proteoglycans in cancer, and so on. qPCR and Western blotting further confirmed that EP could suppress TIMP1, SOCS3, ANGPTL4, CDO1, and SERPINE1 expressions in MCAO rats. CONCLUSION: EP can improve CIRI in vivo, the mechanism may relate to TIMP1 expression and HIF-1 pathway, which provided novel targets for CIRI treatment.

Combining metabolomics and network pharmacology to investigate the protective effect of Jiawei Xinglou Chengqi Granules in ischemic stroke.

Jiawei Xinglou Chengqi Granule (JXCG) is an effective herbal medicine for the treatment of ischemic stroke (IS). JXCG has been shown to effectively ameliorate cerebral ischemic symptoms in clinical practice, but the underlying mechanisms are unclear. In this study, we investigated the mechanisms of action of JXCG in the treatment of IS by combining metabolomics with network pharmacology. The chemical composition of JXCG was analyzed using ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Ultra-high performance liquid chromatography-tandem time-of-flight mass spectrometry (UHPLC-Q-TOF MS) untargeted metabolomics were used to identify differential metabolites within metabolic pathways. Network pharmacology was applied to mine potential targets of JXCG in the treatment of IS. The identified key targets were validated by constructing an integrated network of metabolomics and network pharmacology and by molecular docking using Cytoscape. The effect of JXCG on IS was evaluated in vivo, and the predicted targets and pathways of JXCG in IS therapy were assessed using immunoblotting. Combining metabolomics and network pharmacology, we identified the therapeutic targets of JXCG for IS. Notably, JXCG lessened neuronal damage and reduced cerebral infarct size in rats with IS. Western blot analysis showed that JXCG upregulated PRKCH and downregulated PRKCE and PRKCQ proteins. Our combined network pharmacology and metabolomics findings showed that JXCG may have therapeutic potential in the treatment of IS by targeting multiple factors and pathways.

Chikusetsu Saponin IVa liposomes modified with a retro-enantio peptide penetrating the blood-brain barrier to suppress pyroptosis in acute ischemic stroke rats.

BACKGROUND: The therapeutic strategies for acute ischemic stroke were faced with substantial constraints, emphasizing the necessity to safeguard neuronal cells during cerebral ischemia to reduce neurological impairments and enhance recovery outcomes. Despite its potential as a neuroprotective agent in stroke treatment, Chikusetsu saponin IVa encounters numerous challenges in clinical application. RESULT: Brain-targeted liposomes modified with THRre peptides showed substantial uptake by bEnd. 3 and PC-12 cells and demonstrated the ability to cross an in vitro blood-brain barrier model, subsequently accumulating in PC-12 cells. In vivo, they could significantly accumulate in rat brain. Treatment with C-IVa-LPs-THRre notably reduced the expression of proteins in the P2RX7/NLRP3/Caspase-1 pathway and inflammatory factors. This was evidenced by decreased cerebral infarct size and improved neurological function in MCAO rats. CONCLUSION: The findings indicate that C-IVa-LPs-THRre could serve as a promising strategy for targeting cerebral ischemia. This approach enhances drug concentration in the brain, mitigates pyroptosis, and improves the neuroinflammatory response associated with stroke.

[Mechanism study of 6-shogaol alleviating cerebral ischemia/reperfusion injury by regulating microRNA-26a-5p/death-associated protein kinase 1].

OBJECTIVE: To investigate whether 6-shogaol (6-SH) alleviates oxygen-glucose deprivation/reoxygenation (OGD/R)-induced neuronal autophagy and calcium overload by promoting the expression of microRNA-26a-5p (miR-26a-5p) and inhibiting death-associated protein kinase 1 (DAPK1), and to explore its potential mechanisms. METHODS: Primary cultured logarithmic growth phase mouse hippocampal neurons HT22 cells were taken and cell counting kit-8 (CCK-8) was used to detect cell viability, searching for the optimal concentration of Na2S2O4. HT22 cells were divided into blank control group (NC group), OGD/R group (sugar-free culture medium + 10 mmol/L Na2S2O4 treatment for 1.5 hours followed by normal culture medium for 4 hours), 6-SH intervention group (cultured with 10 µmol/L 6-SH for 4 hours after OGD), negative control inhibitor pretreatment group (transfected with negative control inhibitor for 48 hours followed by OGD, then cultured with 6-SH for 4 hours), and miR-26a-5p inhibitor pretreatment group (transfected with miR-26a-5p inhibitor for 48 hours followed by OGD, then cultured with 6-SH for 4 hours). Cell viability of each group was detected by CCK-8 method; cell ultrastructure was observed under transmission electron microscopy; real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the gene expressions of DAPK1 and miR-26a-5p; molecular docking were used to verify the interaction between 6-SH and miR-26a-5p; dual-luciferase assay was used to verify the targeting relationship between DAPK1 and miR-26a-5p; flow cytometry was used to determine the levels of intracellular Ca2+; Western blotting was used to detect the protein expressions of phosphorylated-glutamate receptor 2B (p-NMDAR2B) Ser1303, DAPK1, autophagy related protein Beclin1, light chain 3 (LC3), and p-DAPK1 Ser308; immunofluorescence was used to detect the expression of LC3 and Beclin1. RESULTS: The results of the CCK-8 assay showed that the cell viability of the 6-SH intervention group was significantly increased compared to the OGD/R group, while the cell viability of the miR-26a-5p inhibitor pretreatment group was significantly decreased compared to the 6-SH intervention group. Transmission electron microscopy revealed that the number of autophagosomes in the 6-SH intervention group was significantly reduced compared to the OGD/R group, while the number of autophagosomes in the miR-26a-5p inhibitor pretreatment group was significantly increased compared to the 6-SH intervention group. RT-qPCR results showed that compared with the OGD/R group, the expression of miR-26a-5p was significantly upregulated and the expression of DAPK1 mRNA was significantly downregulated in the 6-SH intervention group; compared with the 6-SH intervention group, the expression of miR-26a-5p was significantly downregulated and the expression of DAPK1 mRNA was significantly upregulated in the miR-26a-5p inhibitor pretreatment group. Molecular docking verified the interaction between 6-SH and miR-26a-5p. Dual-luciferase reporter gene assay showed that compared with the negative control group, mmu-miR-26a-5p significantly downregulated the luciferase expression of m-DAPK1-3UTR-WT, indicating a binding interaction between them. Flow cytometry results showed that compared with the OGD/R group, the level of intracellular Ca2+; was significantly decreased in the 6-SH intervention group; compared with the 6-SH intervention group, the level of Ca2+ was significantly increased in the miR-26a-5p inhibitor pretreatment group. Western blotting results showed that compared with the OGD/R group, the protein expressions of p-NMDAR2B Ser1303, DAPK1, Beclin1, and LC3 were significantly decreased in the 6-SH intervention group (p-NMDAR2B Ser1303/ß-actin: 2.34±0.27 vs. 4.78±0.39, DAPK1/ß-actin: 1.40±0.13 vs. 2.37±0.21, Beclin1/ß-actin: 2.61±0.32 vs. 4.32±0.29, LC3/ß-actin: 2.52±0.45 vs. 5.09±0.18, all P < 0.05), while the protein expression of p-DAPK1 Ser308 was significantly increased (p-DAPK1 Ser308/ß-actin: 0.66±0.09 vs. 0.40±0.02, P < 0.05); compared with the 6-SH intervention group, the protein expressions of p-NMDAR2B Ser1303, DAPK1, Beclin1, and LC3 were significantly increased in the miR-26a-5p inhibitor pretreatment group (p-NMDAR2B Ser1303/ß-actin: 4.08±0.14 vs. 2.34±0.27, DAPK1/ß-actin: 1.96±0.15 vs. 1.40±0.13, Beclin1/ß-actin: 3.92±0.31 vs. 2.61±0.32, LC3/ß-actin: 4.33±0.33 vs. 2.52±0.45, all P < 0.05), while the expression of p-DAPK1 Ser308 protein was significantly decreased (p-DAPK1 Ser308/ß-actin: 0.33±0.12 vs. 0.66±0.09, P < 0.05); immunofluorescence staining showed that compared with the OGD/R group, the fluorescence intensity of LC3 and Beclin1 was significantly decreased in the 6-SH intervention group; compared with the 6-SH intervention group, the fluorescence intensity of LC3 and Beclin1 was significantly increased in the miR-26a-5p inhibitor pretreatment group. CONCLUSIONS: 6-SH can alleviate neuronal damage by regulating miR-26a-5p/DAPK1 to reduce autophagy and calcium overload in cells.

Reversal of cerebral ischaemia and hypoxia and of sickness behaviour by megadose sodium ascorbate in ovine Gram-negative sepsis.

BACKGROUND: The mechanisms by which megadose sodium ascorbate improves clinical status in experimental sepsis is unclear. We determined its effects on cerebral perfusion, oxygenation, and temperature, and plasma levels of inflammatory biomarkers, nitrates, nitrites, and ascorbate in ovine Gram-negative sepsis. METHODS: Sepsis was induced by i.v. infusion of live Escherichia coli for 31 h in unanaesthetised Merino ewes instrumented with a combination sensor in the frontal cerebral cortex to measure tissue perfusion, oxygenation, and temperature. Fluid resuscitation at 23 h was followed by i.v. megadose sodium ascorbate (0.5 g kg-1 over 30 min+0.5 g kg-1 h-1 for 6.5 h) or vehicle (n=6 per group). Norepinephrine was titrated to restore mean arterial pressure (MAP) to 70-80 mm Hg. RESULTS: At 23 h of sepsis, MAP (mean [sem]: 85 [2] to 64 [2] mm Hg) and plasma ascorbate (27 [2] to 15 [1] µM) decreased (both P<0.001). Cerebral ischaemia (901 [58] to 396 [40] units), hypoxia (34 [1] to 19 [3] mm Hg), and hyperthermia (39.5 [0.1]°C to 40.8 [0.1]°C) (all P<0.001) developed, accompanied by malaise and lethargy. Sodium ascorbate restored cerebral perfusion (703 [121] units], oxygenation (30 [2] mm Hg), temperature (39.2 [0.1]°C) (all PTreatment<0.05), and the behavioural state to normal. Sodium ascorbate slightly reduced the sepsis-induced increase in interleukin-6, returned VEGF-A to normal (both PGroupxTime<0.01), and increased plasma ascorbate (20 000 [300] µM; PGroup<0.001). The effects of sodium ascorbate were not reproduced by equimolar sodium bicarbonate. CONCLUSIONS: Megadose sodium ascorbate rapidly reversed sepsis-induced cerebral ischaemia, hypoxia, hyperthermia, and sickness behaviour. These effects were not reproduced by an equimolar sodium load.

Modulating the RPS27A/PSMD12/NF-κB pathway to control immune response in mouse brain ischemia-reperfusion injury.

BACKGROUND: Investigating immune cell infiltration in the brain post-ischemia-reperfusion (I/R) injury is crucial for understanding and managing the resultant inflammatory responses. This study aims to unravel the role of the RPS27A-mediated PSMD12/NF-κB axis in controlling immune cell infiltration in the context of cerebral I/R injury. METHODS: To identify genes associated with cerebral I/R injury, high-throughput sequencing was employed. The potential downstream genes were further analyzed using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI) analyses. For experimental models, primary microglia and neurons were extracted from the cortical tissues of mouse brains. An in vitro cerebral I/R injury model was established in microglia using the oxygen-glucose deprivation/reoxygenation (OGD/R) technique. In vivo models involved inducing cerebral I/R injury in mice through the middle cerebral artery occlusion (MCAO) method. These models were used to assess neurological function, immune cell infiltration, and inflammatory factor release. RESULTS: The study identified RPS27A as a key player in cerebral I/R injury, with PSMD12 likely acting as its downstream regulator. Silencing RPS27A in OGD/R-induced microglia decreased the release of inflammatory factors and reduced neuron apoptosis. Additionally, RPS27A silencing in cerebral cortex tissues mediated the PSMD12/NF-κB axis, resulting in decreased inflammatory factor release, reduced neutrophil infiltration, and improved cerebral injury outcomes in I/R-injured mice. CONCLUSION: RPS27A regulates the expression of the PSMD12/NF-κB signaling axis, leading to the induction of inflammatory factors in microglial cells, promoting immune cell infiltration in brain tissue, and exacerbating brain damage in I/R mice. This study introduces novel insights and theoretical foundations for the treatment of nerve damage caused by I/R, suggesting that targeting the RPS27A and downstream PSMD12/NF-κB signaling axis for drug development could represent a new direction in I/R therapy.

Single-nucleus RNA sequencing reveals glial cell type-specific responses to ischemic stroke in male rodents.

Neuroglia critically shape the brain´s response to ischemic stroke. However, their phenotypic heterogeneity impedes a holistic understanding of the cellular composition of the early ischemic lesion. Here we present a single cell resolution transcriptomics dataset of the brain´s acute response to infarction. Oligodendrocyte lineage cells and astrocytes range among the most transcriptionally perturbed populations and exhibit infarction- and subtype-specific molecular signatures. Specifically, we find infarction restricted proliferating oligodendrocyte precursor cells (OPCs), mature oligodendrocytes and reactive astrocytes, exhibiting transcriptional commonalities in response to ischemic injury. OPCs and reactive astrocytes are involved in a shared immuno-glial cross talk with stroke-specific myeloid cells. Within the perilesional zone, osteopontin positive myeloid cells accumulate in close proximity to CD44+ proliferating OPCs and reactive astrocytes. In vitro, osteopontin increases the migratory capacity of OPCs. Collectively, our study highlights molecular cross talk events which might govern the cellular composition of acutely infarcted brain tissue.

[Exogenous leptin improves cerebral ischemia-reperfusion-induced glutamate excitotoxic injury in mice by up-regulating GLT-1 and GLAST expression in astrocytes].

OBJECTIVE: To investigate the protective effect of exogenous leptin against focal cerebral ischemia-reperfusion (I/R) injury in mice and explore the underlying mechanism. METHODS: A total of 100 C57BL/6 mice were randomly divided into 5 groups, including a sham-operated group, cerebral I/R model group, and 3 leptin treatment groups with intraperitoneal injections of 0.5, 1.0 or 2.0 leptin immediately after occlusion of the internal carotid artery. At 24 h after reperfusion, neurological function scores of the mice were assessed, and TTC staining was used to determine the area of cerebral infarction. The pathological changes in the cortical brain tissue of the mice were observed using HE staining, and degenerative damage of the cortical neurons were assessed with Fluoro-Jade C staining. The expression of glial fibrillary acidic protein in cortical brain tissues was detected using immunohistochemistry and Western blotting. In another 45 C57BL/6 mice with sham operation, I/R modeling, or leptin (1 mg/kg) treatment, glutamic acid in the cortical brain tissue was detected using glutamate assay, and cortical glutamate-aspartate transporter (GLAST) and glutamate transporter-1 (GLT-1) protein expressions were detected using immunohistochemistry. RESULTS: Compared with the I/R model mice, the leptin-treated mice had significantly lower neurological deficit scores, smaller cerebral infarct area, milder pathologies in the cortical brain tissue, and lessened cortical neuronal damage with normal morphology and less excessive proliferation of the astrocytes. Leptin treatment significantly up-regulated the expressions of GLT-1 and GLAST and lowered the content of glutamic acid in the brain tissue of the I/R mice. CONCLUSION: Exogenous leptin has obvious neuroprotective effect against cerebral I/R injury in mice, mediated probably by controlling excessive astrocyte proliferation and up-regulating cortical GLT-1 and GLAST expressions to reduce glutamate-mediated excitotoxic injury of the astrocytes.

[Soy isoflavones alleviates calcium overload in rats with cerebral ischemia-reperfusion by inhibiting the Wnt/Ca2+ signaling pathway].

OBJECTIVE: To explore the mechanism by which soybean isoflavone (SI) reduces calcium overload induced by cerebral ischemia-reperfusion (I/R). METHODS: Forty-eight SD rats were randomized into 4 groups to receive sham operation, cerebral middle artery occlusion for 2 h followed by 24 h of reperfusion (I/R model group), or injection of adeno-associated virus carrying Frizzled-2 siRNA or empty viral vector into the lateral cerebral ventricle after modeling.Western blotting was used to examine Frizzled-2 knockdown efficiency and changes in protein expressions in the Wnt/Ca2+ signaling pathway.Calcium levels and pathological changes in the ischemic penumbra (IP) were measured using calcium chromogenic assay and HE staining, respectively.Another 72 SD randomly allocated for sham operation, I/R modeling, or soy isoflavones pretreatment before modeling were examined for regional cerebral blood flow using a Doppler flowmeter, and the cerebral infarct volume was assessed using TTC staining.Pathologies in the IP area were evaluated using HE and Nissl staining, and ROS level, Ca2+ level, cell apoptosis, and intracellular calcium concentration were analyzed using immunofluorescence assay or flow cytometry; the protein expressions of Wnt5a, Frizzled-2, and P-CaMK Ⅱ in the IP were detected with Western blotting and immunohistochemistry. RESULTS: In rats with cerebral I/R, Frizzled-2 knockdown significantly lowered calcium concentration (P < 0.001) and the expression levels of Wnt5a, Frizzled-2, and P-CaMK Ⅱ in the IP area.In soy isoflavones-pretreated rats, calcium concentration, ROS and MDA levels, cell apoptosis rate, cerebral infarct volume, and expression levels of Wnt/Ca2+ signaling pathway-related proteins were all significantly lower while SOD level was higher than those in rats in I/R model group. CONCLUSION: Soy isoflavones can mitigate calcium overload in rats with cerebral I/R by inhibiting the Wnt/Ca2+ signaling pathway.

In vivo mapping of cellular resolution neuropathology in brain ischemia with diffusion MRI.

Noninvasive mapping of cellular pathology can provide critical diagnostic and prognostic information. Recent advances in diffusion magnetic resonance imaging enabled in vivo examination of tissue microstructures well beyond the imaging resolution. Here, we proposed to use diffusion time-dependent diffusion kurtosis imaging (tDKI) to simultaneously assess cellular morphology and transmembrane permeability in hypoxic-ischemic (HI) brain injury. Through numerical simulations and organoid imaging, we demonstrated the feasibility of capturing effective size and permeability changes using tDKI. In vivo MRI of HI-injured mouse brains detected a shift of the tDKI peak to longer diffusion times, suggesting swelling of the cellular processes. Furthermore, we observed a faster decrease of the tDKI tail, reflecting increased transmembrane permeability associated with up-regulated water exchange or necrosis. Such information, unavailable from a single diffusion time, can predict salvageable tissues. Preliminary applications of tDKI in patients with ischemic stroke suggested increased transmembrane permeability in stroke regions, illustrating tDKI's potential for detecting pathological changes in the clinics.

Disintegration of Cav-1/ß-catenin complex attenuates neuronal death after ischemia-reperfusion injury by promoting ß-catenin nuclear translocation.

BACKGROUND: The roles of Caveolin-1 (Cav-1) and the Wnt/ß-catenin signaling pathways in cerebral ischemia-reperfusion (I/R) injury are well established. The translocation of ß-catenin into the nucleus is critical for regulating neuronal apoptosis, repair, and neurogenesis within the ischemic brain. It has been reported that the scaffold domain of Caveolin-1 (Cav-1) (residues 95-98) interacts with ß-catenin (residues 330-337). However, the specific contribution of the Cav-1/ß-catenin complex to I/R injury remains unknown. METHODS AND RESULTS: To investigate the mechanism underlying the involvement of the Cav-1/ß-catenin complex in the subcellular translocation of ß-catenin and its subsequent effects on cerebral I/R injury, we treated ischemic brains with ASON (Cav-1 antisense oligodeoxynucleotides) or FTVT (a competitive peptide antagonist of the Cav-1 and ß-catenin interaction). Our study demonstrated that the binding of Cav-1 to ß-catenin following I/R injury prevented the nuclear accumulation of ß-catenin. Treatment with ASON or FTVT after I/R injury significantly increased the levels of nuclear ß-catenin. Furthermore, ASON reduced the phosphorylation of ß-catenin at Ser33, Ser37, and Thr41, which contributes to its proteasomal degradation, while FTVT increased phosphorylation at Tyr333, which is associated with its nuclear translocation. CONCLUSIONS: The above results indicate that the formation of the Cav-1/ß-catenin complex anchors ß-catenin in the cytoplasm following I/R injury. Additionally, both ASON and FTVT treatments attenuated neuronal death in ischemic brains. Our study suggests that targeting the interaction between Cav-1 and ß-catenin serve as a novel therapeutic strategy to protect against neuronal damage during cerebral injury.

FABP3 Induces Mitochondrial Autophagy to Promote Neuronal Cell Apoptosis in Brain Ischemia-Reperfusion Injury.

This study elucidates the molecular mechanisms by which FABP3 regulates neuronal apoptosis via mitochondrial autophagy in the context of cerebral ischemia-reperfusion (I/R). Employing a transient mouse model of middle cerebral artery occlusion (MCAO) established using the filament method, brain tissue samples were procured from I/R mice. High-throughput transcriptome sequencing on the Illumina CN500 platform was performed to identify differentially expressed mRNAs. Critical genes were selected by intersecting I/R-related genes from the GeneCards database with the differentially expressed mRNAs. The in vivo mechanism was explored by infecting I/R mice with lentivirus. Brain tissue injury, infarct volume ratio in the ischemic penumbra, neurologic deficits, behavioral abilities, neuronal apoptosis, apoptotic factors, inflammatory factors, and lipid peroxidation markers were assessed using H&E staining, TTC staining, Longa scoring, rotation experiments, immunofluorescence staining, and Western blot. For in vitro validation, an OGD/R model was established using primary neuron cells. Cell viability, apoptosis rate, mitochondrial oxidative stress, morphology, autophagosome formation, membrane potential, LC3 protein levels, and colocalization of autophagosomes and mitochondria were evaluated using MTT assay, LDH release assay, flow cytometry, ROS/MDA/GSH-Px measurement, transmission electron microscopy, MitoTracker staining, JC-1 method, Western blot, and immunofluorescence staining. FABP3 was identified as a critical gene in I/R through integrated transcriptome sequencing and bioinformatics analysis. In vivo experiments revealed that FABP3 silencing mitigated brain tissue damage, reduced infarct volume ratio, improved neurologic deficits, restored behavioral abilities, and attenuated neuronal apoptosis, inflammation, and mitochondrial oxidative stress in I/R mice. In vitro experiments demonstrated that FABP3 silencing restored OGD/R cell viability, reduced neuronal apoptosis, and decreased mitochondrial oxidative stress. Moreover, FABP3 induced mitochondrial autophagy through ROS, which was inhibited by the free radical scavenger NAC. Blocking mitochondrial autophagy with sh-ATG5 lentivirus confirmed that FABP3 induces mitochondrial dysfunction and neuronal apoptosis by activating mitochondrial autophagy. In conclusion, FABP3 activates mitochondrial autophagy through ROS, leading to mitochondrial dysfunction and neuronal apoptosis, thereby promoting cerebral ischemia-reperfusion injury.

Forsythoside B alleviates cerebral ischemia-reperfusion injury via inhibiting NLRP3 inflammasome mediated by SIRT1 activation.

BACKGROUND: The inflammatory response is a key factor in the pathogenesis of cerebral ischemia/reperfusion injury (CIRI), and anti-inflammatory interventions may offer a promising therapeutic strategy. Forsythoside B (FB) is a phenylethanoid glycoside isolated from Forsythiae fructus, which has been reported to have anti-inflammatory effects. However, the mechanism of the neuroprotective effect of FB on CIRI remains unclear. METHODS: Adult male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion/reperfusion (MCAO/R). FB was administered intraperitoneally for 3 days prior to MCAO/R. Cerebral infarct volume and neurological deficit score were used as indices to evaluate MCAO/R injury. The serum levels of inflammatory factors and antioxidant enzymes were measured. The activation of silent information regulator 2 homolog 1 (Sirt1) and the inhibition of the nucleotide-binding oligomerization domain-like receptor with a pyrin domain 3 (NLRP3) pathway were assessed through western blot and immunohistochemistry analysis. Furthermore, the rats were treated with Sirt1 shRNA 3 days before MCAO/R by stereotactical injection into the ipsilateral hemispheric region to assess the impact of Sirt1 knockdown on the protection of FB during MCAO/R. RESULTS: FB reduced cerebral infarct volume and neurological deficit score in MCAO/R rats. FB reduced pathological changes and cell apoptosis in the hippocampal CA1 region and cortex on the ischemic side of rats. FB inhibited the serum levels of inflammatory factors and increased the activities of antioxidant enzymes. Further study showed that FB inhibited the activation of the NLRP3 pathway and induced Sirt1 activation. CONCLUSION: FB demonstrated neuroprotective and anti-inflammatory effects by inhibiting the NLRP3 pathway through Sirt1 activation in CIRI.

The Effect of Intranasal Administration of Gangliosides on the Viability of CA1 Hippocampal Neurons in Rat Two-Vessel Occlusion Model of Forebrain Ischemia/Reperfusion Injury.

Intranasal administration of total bovine brain gangliosides (6 mg/kg) to rats protected the CA1 hippocampal neurons from the death caused by two-vessel occlusion model (with hypotension) of forebrain ischemia/reperfusion injury. The immunohistochemical reaction of specific antibodies to marker proteins of activated microglia (Iba1) and astrocytes (GFAP) in hippocampal slices revealed the neuroprotective effect of exogenous gangliosides which can be mostly explained by their ability to suppress neuroinflammation and gliosis. The expression of neurotrophic factor BDNF in the CA1 region of hippocampus did not differ in sham-operated rats and animals exposed to ischemia/reperfusion. However, the administration of gangliosides increased the BDNF expression in both control and ischemic groups. The intranasal route of administration allows using lower concentrations of gangliosides preventing the death of hippocampal neurons.

ARMC10 regulates mitochondrial dynamics and affects mitochondrial function via the Wnt/ß-catenin signalling pathway involved in ischaemic stroke.

Mitochondrial dynamics has emerged as an important target for neuronal protection after cerebral ischaemia/reperfusion. Therefore, the aim of this study was to investigate the mechanism by which ARMC10 regulation of mitochondrial dynamics affects mitochondrial function involved in ischaemic stroke (IS). Mitochondrial morphology was detected by laser scanning confocal microscopy (LSCM), and mitochondrial ultrastructural alterations were detected by electron microscopy. The expression of mitochondrial dynamics-related genes Drp1, Mfn1, Mfn2, Fis1, OPA1 and ARMC10 and downstream target genes c-Myc, CyclinD1 and AXIN2 was detected by RT-qPCR. Western blot was used to detect the protein expression of ß-catenin, GSK-3ß, p-GSK-3ß, Bcl-2 and Bax. DCFH-DA fluorescent probe was to detect the effect of ARMC10 on mitochondrial ROS level, Annexin V-FITC fluorescent probe was to detect the effect of ARMC10 on apoptosis, and ATP assay kit was to detect the effect of ARMC10 on ATP production. Mitochondrial dynamics was dysregulated in clinical IS samples and in the OGD/R cell model, and the relative expression of ARMC10 gene was significantly decreased in IS group (p < 0.05). Knockdown and overexpression of ARMC10 could affect mitochondrial dynamics, mitochondrial function and neuronal apoptosis. Agonist and inhibitor affected mitochondrial function and neuronal apoptosis by targeting Wnt/ß-Catenin signal pathway. In the OGD/R model, ARMC10 affected mitochondrial function and neuronal apoptosis through the mechanism that regulates Wnt/ß-catenin signalling pathway. ARMC10 regulates mitochondrial dynamics and protects mitochondrial function by activating Wnt/ß-catenin signalling pathway, to exert neuroprotective effects.

Phelligridimer A enhances the expression of mitofusin 2 and protects against cerebral ischemia/reperfusion injury.

Mitochondrial dysfunction and endoplasmic reticulum (ER) stress play pivotal roles in the pathology of cerebral ischemia. In this study, we investigated whether phelligridimer A (PA), an active compound isolated from the medicinal and edible fungus Phellinus igniarius, ameliorates ischemic cerebral injury by restoring mitochondrial function and restricting ER stress. An in vitro cellular model of ischemic stroke-induced neuronal damage was established by exposing HT-22 neuronal cells to oxygen-glucose deprivation/reoxygenation (OGD/R). An in vivo animal model was established in rats subjected to middle cerebral artery occlusion/reperfusion (MCAO/R). The results showed that PA (1-10 µM) dose-dependently increased HT-22 cell viability, reduced OGD/R-induced lactate dehydrogenase release, and reversed OGD/R-induced apoptosis. PA reduced OGD/R-induced accumulation of reactive oxygen species, restored mitochondrial membrane potential, and increased ATP levels. Additionally, PA reduced the expression of the 78-kDa glucose-regulated protein (GRP78) and the phosphorylation of inositol-requiring enzyme-1α (p-IRE1α) and eukaryotic translation-initiation factor 2α (p-eIF2α). PA also inhibited the activation of the mitogen-activated protein kinase (MAPK) pathway in the OGD/R model. Moreover, treatment with PA restored the expression of mitofusin 2 (Mfn-2), a protein linking mitochondria and ER. The silencing of Mfn-2 abolished the protective effects of PA. The results from the animal study showed that PA (3-10 mg/kg) significantly reduced the volume of cerebral infarction and neurological deficits, which were accompanied by an increased level of Mfn-2, and decreased activation of the ER stress in the penumbra of the ipsilateral side after MCAO/R in rats. Taken together, these results indicate that PA counteracts cerebral ischemia-induced injury by restoring mitochondrial function and reducing ER stress. Therefore, PA might be a novel protective agent to prevent ischemia stroke-induced neuronal injury.

Molecular Pathogenesis of Ischemic and Hemorrhagic Strokes: Background and Therapeutic Approaches.

Stroke represents one of the neurological diseases most responsible for death and permanent disability in the world. Different factors, such as thrombus, emboli and atherosclerosis, take part in the intricate pathophysiology of stroke. Comprehending the molecular processes involved in this mechanism is crucial to developing new, specific and efficient treatments. Some common mechanisms are excitotoxicity and calcium overload, oxidative stress and neuroinflammation. Furthermore, non-coding RNAs (ncRNAs) are critical in pathophysiology and recovery after cerebral ischemia. ncRNAs, particularly microRNAs, and long non-coding RNAs (lncRNAs) are essential for angiogenesis and neuroprotection, and they have been suggested to be therapeutic, diagnostic and prognostic tools in cerebrovascular diseases, including stroke. This review summarizes the intricate molecular mechanisms underlying ischemic and hemorrhagic stroke and delves into the function of miRNAs in the development of brain damage. Furthermore, we will analyze new perspectives on treatment based on molecular mechanisms in addition to traditional stroke therapies.

Overexpression of olfactory receptor 78 ameliorates brain injury in cerebral ischaemia-reperfusion rats by activating Prkaca-mediated cAMP/PKA-MAPK pathway.

Ischemic stroke is one of the main causes of disability and death. However, recanalization of occluded cerebral arteries is effective only within a very narrow time window. Therefore, it is particularly important to find neuroprotective biological targets for cerebral artery recanalization. Here, gene expression profiles of datasets GSE160500 and GSE97537 were downloaded from the GEO database, which were related to ischemic stroke in rats. Olfactory receptor 78 (Olfr78) was screened, and which highly associated with Calcium signalling pathway and MAPK pathway. Interacting protein of Olfr78, Prkaca, was predicted by STRING, and their interaction was validated by Co-IP analysis. Then, a rat model of middle cerebral artery occlusion/reperfusion (MCAO/R) and a neuronal cell model stimulated by oxygen-glucose deprivation/reoxygenation (OGD/R) were constructed, and the results showed that expression of Olfr78 and Prkaca was downregulated in MCAO rats and OGD/R-stimulated neurons. Overexpression of Olfr78 or Prkaca inhibited the secretion of inflammatory factors, Ca2+ overload, and OGD/R-induced neuronal apoptosis. Moreover, Overexpression of Prkaca increased protein levels of cAMP, PKA and phosphorylated p38 in OGD/R-stimulated neurons, while SB203580, a p38 inhibitor, treatment inhibited activation of the cAMP/PKA-MAPK pathway and counteracted the effect of Olfr78 overexpression on improvement of neuronal functions. Meanwhile, overexpression of Olfr78 or Prkaca markedly inhibited neuronal apoptosis and improved brain injury in MCAO/R rats. In conclusion, overexpression of Olfr78 inhibited Ca2+ overload and reduced neuronal apoptosis in MCAO/R rats by promoting Prkaca-mediated activation of the cAMP/PKA-MAPK pathway, thereby improving brain injury in cerebral ischaemia-reperfusion.

Alterations in brain fluid physiology during the early stages of development of ischaemic oedema.

Oedema occurs when higher than normal amounts of solutes and water accumulate in tissues. In brain parenchymal tissue, vasogenic oedema arises from changes in blood-brain barrier permeability, e.g. in peritumoral oedema. Cytotoxic oedema arises from excess accumulation of solutes within cells, e.g. ischaemic oedema following stroke. This type of oedema is initiated when blood flow in the affected core region falls sufficiently to deprive brain cells of the ATP needed to maintain ion gradients. As a consequence, there is: depolarization of neurons; neural uptake of Na+ and Cl- and loss of K+; neuronal swelling; astrocytic uptake of Na+, K+ and anions; swelling of astrocytes; and reduction in ISF volume by fluid uptake into neurons and astrocytes. There is increased parenchymal solute content due to metabolic osmolyte production and solute influx from CSF and blood. The greatly increased [K+]isf triggers spreading depolarizations into the surrounding penumbra increasing metabolic load leading to increased size of the ischaemic core. Water enters the parenchyma primarily from blood, some passing into astrocyte endfeet via AQP4. In the medium term, e.g. after three hours, NaCl permeability and swelling rate increase with partial opening of tight junctions between blood-brain barrier endothelial cells and opening of SUR1-TPRM4 channels. Swelling is then driven by a Donnan-like effect. Longer term, there is gross failure of the blood-brain barrier. Oedema resolution is slower than its formation. Fluids without colloid, e.g. infused mock CSF, can be reabsorbed across the blood-brain barrier by a Starling-like mechanism whereas infused serum with its colloids must be removed by even slower extravascular means. Large scale oedema can increase intracranial pressure (ICP) sufficiently to cause fatal brain herniation. The potentially lethal increase in ICP can be avoided by craniectomy or by aspiration of the osmotically active infarcted region. However, the only satisfactory treatment resulting in retention of function is restoration of blood flow, providing this can be achieved relatively quickly. One important objective of current research is to find treatments that increase the time during which reperfusion is successful. Questions still to be resolved are discussed.