Reperfusion injury following cerebral ischemia: pathophysiology, MR imaging, and potential therapies

Design and synthesis of 1,4,8-triazaspiro[4.5]decan-2-one derivatives as novel mitochondrial permeability transition pore inhibitors

Ischaemia/reperfusion injury (IRI) is a condition that occurs when tissues from different organs undergo reperfusion following an ischaemic event. The mitochondrial permeability transition pore (mPTP), a multiprotein platform including structural components of ATP synthase with putative gate function, is an emerging pharmacological target that could be modulated to facilitate the restoration of organ function after a hypoxic insult. Herein, we reported the synthesis and biological characterisation of new molecules with a 1,4,8-triaza-spiro[4.5]decan-2-one framework of potential interest for the treatment of IRI able to inhibit the opening of mPTP in a cardiac model in vitro. Modelling studies were useful to rationalise the observed structure-activity relationship detecting a binding site for the investigated molecules at the interface between the c8-ring and subunit a of ATP synthase. Compound 14e was shown to display high potency as mPTP inhibitor combined with the capability to counteract cardiomyocytes death in an in vitro model of hypoxia/reoxygenation.

Impact of Transchalcone on Neurological Outcomes in Cerebral Ischemia-reperfusion Injury in Rat: Role of AMP-activated Protein Kinase-mitochondrial Signaling Pathways

ABSTRACT

Cerebral ischemia-reperfusion (CIR) injury results in significant secondary brain damage after ischemic stroke due to oxidative stress, mitochondrial dysfunction, and neuroinflammation. Transchalcone (TCH), a polyphenolic compound, exhibits antioxidant and anti-inflammatory properties that may contribute to neuroprotection. The present study investigated the potential protective effects of TCH in a rat model of CIR, focusing on its impact on the activation of AMP-activated protein kinase (AMPK) pathway, mitochondrial function, and inflammatory mediators. Sixty adult Sprague-Dawley rats were randomly divided into five groups of Control, CIR (ischemia-reperfusion only), CIR+TCH (CIR with TCH), CIR+CC (CIR with compound C), and CIR+CC+TCH (CIR with compound C plus TCH). TCH (100 μg/kg b.w per day) was given intraperitoneally over 7 days before CIR injury to animals. Middle cerebral artery occlusion was performed for 60 min to induce cerebral ischemia, and then blood flow was restored (reperfusion) for 24 h. Neuromotor function was assessed using neurological scoring, rotarod, and grid tests. The infarct volumes were determined using 2,3,5-triphenyltetrazolium chloride staining. Mitochondrial function was evaluated using fluorometric and calorimetric methods. Oxidative stress and inflammatory mediators were measured by enzyme-linked immunosorbent assay. Protein expression was analyzed using Western blotting. CIR significantly impaired neuromotor function, increased infarct volume, elevated mitochondrial reactive oxygen species (ROS) levels, and disrupted adenosine triphosphate (ATP) synthesis and manganese superoxide dismutase (Mn-SOD) activity. It also heightened pro-inflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor-alpha, and nuclear factor kappa B levels while reducing the anti-inflammatory IL-10 level. TCH treatment significantly attenuated CIR outcomes by promoting AMPK phosphorylation, upregulating peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) and nuclear factor erythroid 2-related factor 2 (NRF2) expression, reducing mitochondrial ROS, improving ATP production and Mn-SOD activity, and suppressing pro-inflammatory cytokine mediators while increasing IL-10. Co-treatment with compound C (a selective AMPK inhibitor) significantly diminished the protective effects of TCH, confirming the contribution of AMPK signaling in its neuroprotective mechanism. TCH provides significant neuroprotection against CIR injury by activating AMPK/PGC-1α and AMPK/NRF2 signaling, preserving mitochondrial function, and modulating inflammation. These findings highlight the therapeutic potential of TCH for ischemic stroke management.

Neuroprotective effect of apo-9'-fucoxanthinone against cerebral ischemia injury by targeting the PI3K/AKT/GSK-3β pathway

Neuronal loss in cerebral ischemia primarily results from the combined effects of inflammatory responses and programmed cell death. Currently, there is an urgent need for potent neuroprotectants targeting both inflammatory and apoptotic responses for the treatment of ischemic stroke. Marine natural products are a vital source of novel drug candidates. Apo-9'-fucoxanthinone (APO-9'), a degradation product of fucoxanthin derived from marine brown algae, is known for its substantial anti-inflammatory effects, yet its neuroprotective action has not been clearly defined. In this study, the neuroprotective effects of APO-9' in alleviating cerebral ischemia injury and the underlying mechanism were primarily explored with the aid of tandem mass tag-based quantitative proteomics. APO-9' was found to markedly decrease the levels of inflammation factors by suppressing the IKK/IκB/NF-κB pathway in lipopolysaccharide (LPS)-induced BV2 cells. It also attenuated apoptotic responses in both LPS-induced BV2 cells and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced SH-SY5Y cells. These neuroprotective effects of APO-9' were linked to the activation of the PI3K/AKT pathway. Intraperitoneal injection of APO-9' in a MCAO mouse model showed significant cerebral protection against ischemia. The involvements of the IKK/IκB/NF-κB and PI3K/AKT/GSK-3β pathways were also confirmed in its alleviation of cerebral ischemia in vivo. This study established that APO-9' exerted neuroprotection against cerebral ischemia by inhibiting inflammatory and apoptotic cascades via the IKK/IκB/NF-κB and PI3K/AKT/GSK-3β signaling pathways.

Exercise preconditioning increases circulating exosome miR-124 expression and alleviates apoptosis in rats with cerebral ischemia-reperfusion injury

OBJECTIVES

Exercise as a non-pharmacological intervention can exert beneficial effects directly through exosomes crossing the blood-brain barrier and reduce apoptosis after cerebral ischaemia/reperfusion injury (CI/RI). miRNA-124 (miR-124) is present in exosomes and plays an important role in regulating cerebral neurological activity; however, the mechanism of the relationship between exercise and the activity of exosomes and apoptosis after CI/RI remains unclear. Therefore, the present study investigated the effects of exercise preconditioning on CI/RI from the perspective of exosomal miR-124 and apoptosis.

METHODS

The middle cerebral artery occlusion/reperfusion (MCAO/R) model was established by blocking the middle cerebral artery, and a motorized running wheel was chosen as the method of exercise preconditioning for rats, the morphology, particle concentration and particle size distribution of the exosome samples were identified at the 6 h, 12 h, and 24 h time points. RT-PCR, western blotting, immunohistochemistry, TUNEL staining, TTC staining and mNSS scores were used to investigate the effects of exercise preconditioning on apoptosis in MCAO/R rats.

RESULTS

The results showed exercise reduced neurological dysfunction and infarct size, increased the content of plasma exocrine miR-124 at 24 h, which inhibited the expression of STAT3, increased the expression of the anti-apoptotic BCL-2, and decreased the expression of the pro-apoptotic BAX, thereby reducing apoptosis.

CONCLUSIONS

Our findings indicated that exercise preconditioning can enhance the anti-apoptotic capacity of tissues in the rat ischemic penumbra and reduce apoptosis after CI/RI via the exosomal miR-124, STAT3, BCL-2/BAX pathway.

Early penumbral FLAIR changes predict tissue fate in patients with large vessel occlusions

BACKGROUND

In patients with an acute ischemic stroke, the penumbra is defined as ischemic tissue that remains salvageable when reperfusion occurs. However, the expected clinical recovery congruent with penumbral salvage is not always observed.

AIMS

We aimed to determine whether the magnetic resonance imaging (MRI)-defined penumbra includes irreversible neuronal loss that impedes expected clinical recovery after reperfusion.

METHODS

In the prospective French Acute Multimodal Imaging Study to Select Patients for Mechanical Thrombectomy (FRAME) and an observational cohort of patients with large vessel occlusions undergoing endovascular treatment, we quantified penumbral integrity by fluid-attenuated inversion recovery (FLAIR) changes. We studied the influence of recanalization status on the evolution of penumbral FLAIR changes and studied penumbral FLAIR changes as predictor of tissue fate and functional outcome on the 90-day modified Rankin Scale (mRS).

RESULTS

Recanalization status did not modify the evolution of rFLAIR signal intensity (SI) over time in the total cohort, but was associated with lower SI in the FRAME subset (b = -0.06, p for interaction = 0.04). Median rFLAIR SI was higher at baseline in the subsequently infarcted penumbra compared to the salvaged (ratio = 1.07, standard deviation (SD) = 0.07 vs 1.03, SD = 0.06 p < 0.0001, n = 150). The severity and extent of rFLAIR SI changes did not predict 90-day functional outcome in univariate (p = 0.09) and multivariate logistic regression (p = 0.4).

CONCLUSIONS

Recanalization status did not influence the evolution of penumbral FLAIR changes. FLAIR SI changes in the baseline penumbra were associated with tissue fate, but not functional outcome.

Unlocking the Potential of l-α-Glycerylphosphorylcholine: From Metabolic Pathways to Therapeutic Applications

l-α-Glycerylphosphorylcholine (GPC), also known as choline alphoscerate or α-glycerophosphorylcholine, serves as both a pharmaceutical product and a dietary supplement. Through its metabolic pathways, GPC acts as the precursor not only of choline and acetylcholine but also of various phospholipids. Extensive preclinical and clinical evidence demonstrates that GPC effectively alleviates cognitive impairment associated with Alzheimer's disease, vascular dementia, cerebral ischemia, stress, and epilepsy, among other conditions. Additionally, GPC has beneficial effects on such conditions and measures as ischemic/hypoxic conditions, ionizing radiation-induced damage, exercise performance, growth hormone release, and liver damage. As well as facilitating cholinergic neurotransmission, evidence also indicates GPC, among other activities, also can promote γ-aminobutyric acid release, enhance protein kinase C activity, facilitate hippocampal neurogenesis, upregulate neurotrophic factors, and inhibit inflammation. In preclinical studies, results indicate that GPC is not genotoxic in vitro or in vivo. Extensive human studies indicate GPC causes no severe adverse effects. Possible risks of atherosclerosis and stroke await necessary validation. In this review, the GPC-related metabolic pathways, pharmacological effects, mechanisms of action, and safety evaluation are discussed with the aim of providing a comprehensive understanding of GPC.

Bioactivity and Neuroprotective Effects of Extra Virgin Olive Oil in a Mouse Model of Cerebral Ischemia: An In Vitro and In Vivo Study

Cerebral ischemia is a pathological condition characterized by complete blood and oxygen supply deprivation to neuronal tissue. The ischemic brain compensates for the rapid decline in ATP levels by increasing the anaerobic glycolysis rate, which leads to lactate accumulation and subsequent acidosis. Astrocytes play a critical role in regulating cerebral energy metabolism. Mitochondria are significant targets in hypoxia-ischemia injury, and disruptions in mitochondrial homeostasis and cellular energetics worsen outcomes, especially in the elderly. Elevated levels of n-3 polyunsaturated fatty acids (PUFAs) protect the adult and neonatal brain from ischemic damage by suppressing inflammation, countering oxidative stress, supporting neurovascular unit reconstruction, and promoting oligodendrogenesis. This study examines extra virgin olive oil (EVOO) treatment on TNC WT and TNC M23 cells, focusing on oxygen consumption and reactive oxygen species (ROS) production. This study investigates the effects of different durations of middle cerebral artery occlusion (MCAo) and EVOO administration on cerebral infarct volume, neurological scores, mitochondrial function, and cell viability. Cerebral infarct volume increased with longer ischemia times, while EVOO treatment (0.5 mg/kg/day) significantly reduced infarction across all MCAo durations. The oxygen consumption assays demonstrate EVOO's dose-dependent stimulation of mitochondrial respiration in astrocytes, particularly at lower concentrations. Furthermore, EVOO-treated cells reduce ROS production during hypoxia, improve cell viability under ischemic stress, and enhance ATP production in ischemic conditions, underscoring EVOO's neuroprotective potential.

Platelet related gene IQGAP1 contributes to the onset and abnormal immune landscape of ischemic stroke patients

INTRODUCTION

Ischemic stroke (IS) is a complex illness resulting from a combination of numerous environmental and genetic risk factors. Recent reports have shed light on the vital role that platelets play in the pathophysiology of IS. Here, we aimed to explore the potential platelet-related genes in IS and investigate the effect of platelet-related genes in the immune microenvironment of IS.

METHODS

The data of IS were retrieved from the Gene Expression Omnibus database. Firstly, we screened the platelet-related genes that were correlated with the onset of IS using differential expression analysis, enrichment analyses, and protein-protein interaction (PPI) network. Moreover, we analyzed the clinical value and functional information of platelet-related genes in IS. Finally, we explored the correlation between platelet-related genes and immune cells' infiltration.

RESULTS

Ten platelet-related genes that were correlated with the onset of IS were identified, among which IQGAP1 was located at the core of the PPI network. IQGAP1 was found to be expressed in the normal brain tissue and its expression was significantly elevated in IS samples. The area under the curve (AUC) values for IQGAP1 in both the GSE16561 and GSE58294 datasets were close to 1. IQGAP1 knockdown might increase OGD/R‑induced HT22 cell viability. Additionally, FoxO signaling pathway, NOD-like receptor signaling pathway, Phagosome and Platelet activation pathways were significantly activated in IS patients with high IQGAP1 expression compared to those with low IQGAP1 expression. The IS patients in the IQGAP1high and IQGAP1low groups showed dramatically different proportions of immune cells and immune-related functions, and the IQGAP1 expression was correlated with the immune cell' infiltration in IS.

CONCLUSIONS

In this study, we identified the IQGAP1 might serve as a potential diagnostic marker for IS, and the IQGAP1 expression was very relevant in determining the immune cell' infiltration in IS patients.

CircRNA: A new target for ischemic stroke

Ischemic stroke, a clinical emergency and disease with a poor prognosis, has a negative impact on the survival index of patients. It is frequently precipitated by a multitude of risk factors, including trauma. Currently, there is a paucity of predictive indicators for early intervention. As stable and abundant RNA in the body, circRNAs play a regulatory role in miRNAs and proteins, which affect the occurrence and development of diseases. Moreover, circRNAs can serve as predictors of clinical diseases. Several studies have demonstrated that circRNAs play pivotal roles in numerous aspects of ischemic stroke. Consequently, circRNAs have emerged as key areas of investigation in the field of ischemic stroke.

Cellular and Intravital Nucleus Imaging by a D-π-A Type of Red-Emitting Two-Photon Fluorescent Probe

The advancement in fluorescent probe technology for visualizing nuclear morphology and nucleic acid distribution in live cells and in vivo has attracted considerable interest within the biomedical research community, as it offers invaluable insights into cellular dynamics across various physiological and pathological contexts. In this study, we present a novel two-photon nucleus-imaging fluorescent probe called Nu-red, which is a typical donor(D)-π-acceptor(A) rotor composed of the donor (dihydroquinoline) and acceptor (pyridiniumylpentadienitrile) parts linked by a single bond. This probe offers several advantages, including long-wavelength excitation and emission (λex/λem = 610/664 nm), favorable quantum yields (1.35-22.15%), excellent two-photon absorption cross-section (425.92 GM), high selectivity and sensitivity, high DNA-binding affinity (Ka = 3.7 × 107 M-1, comparable to that of the commercial nucleus stain Hoechst 33342), rapid entry into the nucleus (1 min), low cytotoxicity, membrane-permeability, good water solubility, applicability to various cell lines, and compatibility with other commercial probes. Leveraging these aforementioned advantages, Nu-red was successfully employed to visualize cell division in living cells, distinguish abnormal division cells from normal ones, and track morphological changes in the nucleus during cell apoptosis. More notably, Nu-red was utilized to visualize nuclear shrinkage and pyknosis in the brain of a living mouse model of ischemic stroke.

α7-Nicotinic Acetylcholine Receptor Activation Modulates BV2 Microglial Plasticity via miR-21/TNF-α/NFκB in Oxygen-Glucose Deprivation/Reoxygenation

Elevated inflammatory reactions are a significant component in cerebral ischemia-reperfusion injury (CIRI). Activation of α7-Nicotinic Acetylcholine Receptor (α7nAChR) reduces stroke-induced inflammation in rats, but the anti-inflammatory pathway in microglia under CIRI condition remains unclear. This study employed qRT-PCR, protein assays, NanoString analysis, and bioinformatics to examine the effects of PNU282987 treatment (α7nAChR agonist) on BV2 microglial functional differentiation in oxygen-glucose deprivation/reoxygenation (OGDR) condition. OGDR significantly increased the gene expression of pro-inflammatory markers such as TNF-α, IL-6, and IL1β, while α7nAChR agonists reduced these markers. The anti-inflammatory gene marker IL-10 was upregulated by α7nAChR agonist treatment. Downstream pathway marker analysis showed that both gene and protein expression of NFκB was associated with anti-inflammatory effects. Blocking microRNA-21 with antagomir reversed the anti-inflammatory effects. NanoString analysis revealed that microRNA-21 inhibition significantly affected inflammation-related genes, including AL1RAP, TLR9, FLT1, PTGIR, NFκB, TREM2, TNF, SMAD7, FOS, CCL5, IFIT1, CFB, CXCL10, IFI44, DDIT3, IRF7, OASL1, IL1A, IFIT2, C3, CD40, STAT2, IFIT3, IL1RN, OAS1A, CSF1, CCL4, CCL2, CCL3, BCL2L1, and ITGB2. Enrichment analysis of upregulated genes identified Gene Ontology Biological Processes related to cytokine responses and TNF-associated pathways. This study highlights α7nAChR activation as a key regulator of anti-inflammatory responses in BV2 microglia under OGDR conditions, with micro-RNA21 identified as a crucial mediator of receptor-driven neuroprotection via the TNF-α/NFκB signalling pathway.

The Effect of Acute Stroke Treatment on S100B, IMA, and Thiol-Disulfide Balance

BACKGROUND

A variety of processes, ranging from blood-brain barrier disruption to circulating biomarkers, contributes to reperfusion injury in acute stroke treatment.

OBJECTIVE

We aimed to investigate the effects of thrombolytic therapy and endovascular thrombectomy therapy on serum S100 calcium-binding protein B, ischemia-modified albumin and thiol-disulfide balance in patients who arrived within the first 6 h of acute ischemic stroke.

MATERIAL AND METHODS

The study considered 66 patients with the diagnosis of acute ischemic stroke who underwent thrombolytic therapy or EVT in the first 6 h, as well as 32 healthy volunteers. Venous blood samples were collected before tPA and EVT and 24 h after treatment. S100B, native thiol, disulfide, total thiol, and Ischemia-modified albumin (IMA) levels were measured.

RESULTS

The S100B, total thiol, and native thiol values of the patients in the tPA group before and after the treatment showed statistical significance (P < 0.001). S100B, total thiol, and native thiol values were shown to be lower. The disulfide and IMA values of the patients in the tPA group did not differ significantly (respectively, P = 0.302, P = 0.054). However, disulfide and IMA levels were found to increase after treatment compared to pretreatment. The patients in the EVT group showed a significant difference in terms of S100B values (P < 0.001) and IMA values (P = 0.024).

CONCLUSIONS

Determining how to protect the brain from free radical damage is important. More research should be carried out on treatments that prevent free radical damage in ischemia-reperfusion injury, as well as treatments for acute ischemic stroke.

Ineffectiveness of 6,2',4'-trimethoxyflavone in mitigating cerebral ischemia/reperfusion injury after post-reperfusion administration in rats

BACKGROUND

Pharmacological inhibition of aryl hydrocarbon receptor (AhR) activation after ischemia alleviates cerebral ischemia/reperfusion (IR) injury.

PURPOSE

To investigate whether AhR antagonist administration after reperfusion was also effective in attenuating cerebral IR injury.

MATERIAL AND METHODS

A total of 24 Sprague-Dawley rats were divided into the sham-operated group (no IR), control group (IR), and 6,2',4'-trimethoxyflavone (TMF) group (IR + TMF administration), with 10 rats assigned to each group. Cerebral IR injury was induced by 60 min of middle cerebral artery occlusion followed by reperfusion. TMF (5 mg/kg) was used as the AhR antagonist and was administered intraperitoneally immediately after reperfusion. Cerebral IR injury was observed using magnetic resonance imaging (MRI) and neurobehavioral assessments at baseline, immediately after ischemia, and at 3 days after ischemia.

RESULTS

On MRI, the TMF group showed no significant differences in relative apparent diffusion coefficient (ADC), T2, and fractional anisotropy (FA) values; midline shift value; and infarct volume. In terms of neurobehavioral function, factors such as grip strength, contralateral forelimb use, time to touch, and time to remove adhesive tape from the forepaw, were also not significantly different between the control and TMF groups.

CONCLUSION

This study demonstrated that AhR treatment after reperfusion had no noticeable effect on reducing cerebral IR injury in rats.

Ischemia-reperfusion injury in a salvaged penumbra: Longitudinal high-tesla perfusion magnetic resonance imaging in a rat model

INTRODUCTION

Although ischemia-reperfusion (I/R) injury varies between cortical and subcortical regions, its effects on specific regions remain unclear. In this study, we used various magnetic resonance imaging (MRI) techniques to examine the spatiotemporal dynamics of I/R injury within the salvaged ischemic penumbra (IP) and reperfused ischemic core (IC) of a rodent model, with the aim of enhancing therapeutic strategies by elucidating these dynamics.

MATERIALS AND METHODS

A total of 17 Sprague-Dawley rats were subjected to 1 h of transient middle cerebral artery occlusion with a suture model. MRI, including diffusion tensor imaging (DTI), T2-weighted imaging, perfusion-weighted imaging, and T1 mapping, was conducted at multiple time points for up to 5 days during the I/R phases. The spatiotemporal dynamics of blood-brain barrier (BBB) modifications were characterized through changes in T1 within the IP and IC regions and compared with mean diffusivity (MD), T2, and cerebral blood flow.

RESULTS

During the I/R phases, the MD of the IC initially decreased, normalized after recanalization, decreased again at 24 h, and peaked on day 5. By contrast, the IP remained relatively stable. Both the IP and IC exhibited hyperperfusion, with the IP reaching its peak at 24 h, followed by resolution, whereas hyperperfusion was maintained in the IC until day 5. Despite hyperperfusion, the IP maintained an intact BBB, whereas the IC experienced persistent BBB leakage. At 24 h, the IC exhibited an increase in the T2 signal, corresponding to regions exhibiting BBB disruption at 5 days.

CONCLUSIONS

Hyperperfusion and BBB impairment have distinct patterns in the IP and IC. Quantitative T1 mapping may serve as a supplementary tool for the early detection of malignant hyperemia accompanied by BBB leakage, aiding in precise interventions after recanalization. These findings underscore the value of MRI markers in monitoring ischemia-specific regions and customizing therapeutic strategies to improve patient outcomes.

Multi-Target and Multi-Phase Adjunctive Cerebral Protection for Acute Ischemic Stroke in the Reperfusion Era

Stroke remains the leading cause of death and disability in some countries, predominantly attributed to acute ischemic stroke (AIS). While intravenous thrombolysis and endovascular thrombectomy are widely acknowledged as effective treatments for AIS, boasting a high recanalization rate, there is a significant discrepancy between the success of revascularization and the mediocre clinical outcomes observed among patients with AIS. It is now increasingly understood that the implementation of effective cerebral protection strategies, serving as adjunctive treatments to reperfusion, can potentially improve the outcomes of AIS patients following recanalization therapy. Herein, we reviewed several promising cerebral protective methods that have the potential to slow down infarct growth and protect ischemic penumbra. We dissect the underlying reasons for the mismatch between high recanalization rates and moderate prognosis and introduce a novel concept of "multi-target and multi-phase adjunctive cerebral protection" to guide our search for neuroprotective agents that can be administered alongside recanalization therapy.

Glycyrrhetinic acid triggers a protective autophagy by inhibiting the JAK2/STAT3 pathway in cerebral ischemia/reperfusion injury

Cerebral ischemia/reperfusion injury (CIRI) is a common feature of ischemic stroke leading to a poor prognosis. Effective treatments targeting I/R injury are still insufficient. The study aimed to investigate the mechanisms, by which glycyrrhizic acid (18β-GA) in ameliorates CIRI. Our results showed that 18β-GA significantly decreased the infarct volume, neurological deficit scores, and pathological changes in the brain tissue of rats after middle cerebral artery occlusion. Western blotting showed that 18β-GA inhibited the expression levels of phosphorylated JAK2 and phosphorylated STAT3. Meanwhile, 18β-GA increased LC3-II protein levels in a reperfusion duration-dependent manner, which was accompanied by an increase in the Bcl-2/Bax ratio. Inhibition of 18β-GA-induced autophagy by 3-methyladenine (3-MA) enhanced apoptotic cell death. In addition, 18β-GA inhibited the JAK2/STAT3 pathway, which was largely activated in response to oxygen-glucose deprivation/reoxygenation. However, the JAK2/STAT3 activator colivelin TFA abolished the inhibitory effect of 18β-GA, suppressed autophagy, and significantly decreased the Bcl-2/Bax ratio. Taken together, these findings suggested that 18β-GA pretreatment ameliorated CIRI partly by triggering a protective autophagy via the JAK2/STAT3 pathway. Therefore might be a potential drug candidate for treating ischemic stroke.

A model of mitochondrial superoxide production during ischaemia-reperfusion injury for therapeutic development and mechanistic understanding

Ischaemia-reperfusion (IR) injury is the paradoxical consequence of the rapid restoration of blood flow to an ischaemic organ. Although reperfusion is essential for tissue survival in conditions such as myocardial infarction and stroke, the excessive production of mitochondrial reactive oxygen species (ROS) upon reperfusion initiates the oxidative damage that underlies IR injury, by causing cell death and inflammation. This ROS production is caused by an accumulation of the mitochondrial metabolite succinate during ischaemia, followed by its rapid oxidation upon reperfusion by succinate dehydrogenase (SDH), driving superoxide production at complex I by reverse electron transport. Inhibitors of SDH, such as malonate, show therapeutic potential by decreasing succinate oxidation and superoxide production upon reperfusion. To better understand the mechanism of mitochondrial ROS production upon reperfusion and to assess potential therapies, we set up an in vitro model of IR injury. For this, isolated mitochondria were incubated anoxically with succinate to mimic ischaemia and then rapidly reoxygenated to replicate reperfusion, driving a burst of ROS formation. Using this system, we assess the factors that contribute to the magnitude of mitochondrial ROS production in heart, brain, and kidney mitochondria, as well as screening for inhibitors of succinate oxidation with therapeutic potential.

The Sirtuin 5 Inhibitor MC3482 Ameliorates Microglia‑induced Neuroinflammation Following Ischaemic Stroke by Upregulating the Succinylation Level of Annexin-A1

In our previous study, we concluded that sirtuin 5 (SIRT5) was highly expressed in microglia following ischaemic stroke, which induced excessive neuroinflammation and neuronal injury. Therefore, SIRT5-targeting interventions should reduce neuroinflammation and protect against ischaemic brain injury. Here, we showed that treatment with a specific SIRT5 inhibitor, MC3482, alleviated microglia-induced neuroinflammation and improved long-term neurological function in a mouse model of stroke. The mice were administrated with either vehicle or 2 mg/kg MC3482 daily for 7 days via lateral ventricular injection following the onset of middle cerebral artery occlusion. The outcome was assessed by a panel of tests, including a neurological outcome score, declarative memory, sensorimotor tests, anxiety-like behavior and a series of inflammatory factors. We observed a significant reduction of infarct size and inflammatory factors, and the improvement of long-term neurological function in the early stages during ischaemic stroke when the mice were treated with MC3482. Mechanistically, the administration of MC3482 suppressed the desuccinylation of annexin-A1, thereby promoting its membrane recruitment and extracellular secretion, which in turn alleviated neuroinflammation during ischaemic stroke. Based on our findings, MC3482 offers promise as an anti-ischaemic stroke treatment that targets directly the disease's underlying factors.

The Role of Neutrophils in Multiple Sclerosis and Ischemic Stroke

Inflammation plays an important role in numerous central nervous system (CNS) disorders. Its role is ambiguous-it can induce detrimental effects, as well as repair and recovery. In response to injury or infection, resident CNS cells secrete numerous factors that alter blood-brain barrier (BBB) function and recruit immune cells into the brain, like neutrophils. Their role in the pathophysiology of CNS diseases, like multiple sclerosis (MS) and stroke, is highly recognized. Neutrophils alter BBB permeability and attract other immune cells into the CNS. Previously, neutrophils were considered a homogenous population. Nowadays, it is known that various subtypes of these cells exist, which reveal proinflammatory or immunosuppressive functions. The primary goal of this review was to discuss the current knowledge regarding the important role of neutrophils in MS and stroke development and progression. As the pathogenesis of these two disorders is completely different, it gives the opportunity to get insight into diverse mechanisms of neutrophil involvement in brain pathology. Our understanding of the role of neutrophils in CNS diseases is still evolving as new aspects of their activity are being unraveled. Neutrophil plasticity adds another level to their functional complexity and their importance for CNS pathophysiology.

Neuroprotective effects of galectin‑1 on cerebral ischemia/reperfusion injury by regulating oxidative stress

Oxidative stress contributes to the pathology of cerebral ischemia/reperfusion (I/R) injury. Galectin-1 has shown an anti-oxidative stress effect. The present study investigated whether this anti-oxidative stress effect can account for the neuroprotective actions of galectin-1 induced by cerebral I/R injury. A cerebral I/R injury model was created in C57Bl/6 mice by transient occlusion of the middle cerebral artery, after which the mice were treated with galectin-1 for 3 days. Infarct volumes were measured. A rotarod test and neurological deficit score assessment was performed to evaluate the neurological deficits. Oxidative stress was evaluated by measuring the levels of reactive oxygen species (ROS) and lipid peroxidation malondialdehyde (MDA), while the anti-oxidative stress status was assessed by measuring molecules such as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidation enzyme (GSH-Px) in the ischemic cerebral hemisphere of mice. The inflammatory cytokines, including Interleukin 1 (IL-1), IL-6 and tumor necrosis factor alpha (TNF-α) were measured, and the expression of microglia was evaluated by immunohistochemistry in the ischemic cerebral hemisphere of mice. Galectin-1 treatment ameliorated neurological deficits and reduced infarct volumes in the mice model with cerebral I/R injury. Moreover, it was demonstrated that galectin-1 can significantly alleviate cerebral I/R injury in the ischemic cerebral hemisphere by decreasing the production of ROS and MDA, but increasing the production of CAT, SOD and GSH-Px. Galectin-1 treatment decreased microglia expression, and IL-1, IL-6 and TNF-α levels in the ischemic cerebral hemisphere of mice. Galectin-1 could improve the outcome of cerebral I/R injury by alleviating oxidative stress. Moreover, the neuroprotective effect of galectin-1 in cerebral ischemia could be related to its anti-oxidative stress effect.

Mitochondrial respiration in peripheral arterial disease depends on stage severity

Peripheral arterial disease (PAD) is an increasing cause of morbidity and its severity is graded based on clinical manifestation. To investigate the influence of the different stages on myopathy of ischemic muscle we analysed severity-dependent effects of mitochondrial respiration in PAD. Eighteen patients with severe PAD, defined as chronic limb-threatening ischemia, 47 patients with intermittent claudication (IC) and 22 non-ischemic controls were analysed. High-resolution respirometry (HRR) was performed on muscle biopsies of gastrocnemius and vastus lateralis muscle of patients in different PAD stages to investigate different respiratory states. Results from HRR are given as median and interquartile range and were normalized to citrate synthase activity (CSA), a marker for mitochondrial content. In order to account for inter-individual differences between patients and controls, we calculated the ratio of O₂-flux in gastrocnemius muscle over vastus muscle ('GV ratio'). CSA of the gastrocnemius muscle as a proxy for mitochondrial content was significantly lower in critical ischemia compared to controls. Mitochondrial respiration normalized to CSA was higher in IC compared to controls. Likewise, the GV ratio was significantly higher in IC compared to control. Mitochondrial respiration and CSA of PAD patients showed stage-dependent modifications with greater changes in the mild PAD stage group (IC).

An Efficient CNN-Based Method for Intracranial Hemorrhage Segmentation from Computerized Tomography Imaging

Intracranial hemorrhage (ICH) resulting from traumatic brain injury is a serious issue, often leading to death or long-term disability if not promptly diagnosed. Currently, doctors primarily use Computerized Tomography (CT) scans to detect and precisely locate a hemorrhage, typically interpreted by radiologists. However, this diagnostic process heavily relies on the expertise of medical professionals. To address potential errors, computer-aided diagnosis systems have been developed. In this study, we propose a new method that enhances the localization and segmentation of ICH lesions in CT scans by using multiple images created through different data augmentation techniques. We integrate residual connections into a U-Net-based segmentation network to improve the training efficiency. Our experiments, based on 82 CT scans from traumatic brain injury patients, validate the effectiveness of our approach, achieving an IOU score of 0.807 ± 0.03 for ICH segmentation using 10-fold cross-validation.

Proper Indication of Decompressive Craniectomy for the Patients with Massive Brain Edema after Intra-arterial Thrombectomy

OBJECTIVE

Numerous studies have indicated that early decompressive craniectomy (DC) for patients with major infarction can be life-saving and enhance neurological outcomes. However, most of these studies were conducted by neurologists before the advent of intra-arterial thrombectomy (IA-Tx). This study aims to determine whether neurological status significantly impacts the final clinical outcome of patients who underwent DC following IA-Tx in major infarction.

METHODS

This analysis included 67 patients with major anterior circulation major infarction who underwent DC after IA-Tx, with or without intravenous tissue plasminogen activator. We retrospectively reviewed the medical records, radiological findings, and compared the neurological outcomes based on the "surgical time window" and neurological status at the time of surgery.

RESULTS

For patients treated with DC following IA-Tx, a Glasgow coma scale (GCS) score of 7 was the lowest score correlated with a favorable outcome (p=0.013). Favorable outcomes were significantly associated with successful recanalization after IA-Tx (p=0.001) and perfusion/diffusion (P/D)-mismatch evident on magnetic resonance imaging performed immediately prior to IA-Tx (p=0.007). However, the surgical time window (within 36 hours, p=0.389; within 48 hours, p=0.283) did not correlate with neurological outcomes.

CONCLUSION

To date, early DC surgery after major infarction is crucial for patient outcomes. However, this study suggests that the indication for DC following IA-Tx should include neurological status (GCS ≤7), as some patients treated with early DC without considering the neurological status may undergo unnecessary surgery. Recanalization of the occluded vessel and P/D-mismatch are important for long-term neurological outcomes.

Fluid shear stress induced-endothelial phenotypic transition contributes to cerebral ischemia-reperfusion injury and repair

Long-term ischemia leads to insufficient cerebral microvascular perfusion and dysfunction. Reperfusion restores physiological fluid shear stress (FSS) but leads to serious injury. The mechanism underlying FSS-induced endothelial injury in ischemia-reperfusion injury (IRI) remains poorly understood. In this study, a rat model of middle cerebral artery occlusion was constructed to explore cerebrovascular endothelial function and inflammation in vivo. Additionally, the rat brain microvascular endothelial cells (rBMECs) were exposed to a laminar FSS of 0.5 dyn/cm2 for 6 h and subsequently restored to physiological fluid shear stress level (2 dyn/cm2) for 2 and 12 h, respectively. We found that reperfusion induced endothelial-to-mesenchymal transition (EndMT) in endothelial cells, leading to serious blood-brain barrier dysfunction and endothelial inflammation, accompanied by the nuclear accumulation of Yes-associated protein (YAP). During the later stage of reperfusion, cerebral endothelium was restored to the endothelial phenotype with a distinct change in mesenchymal-to-endothelial transition (MEndT), while YAP was translocated and phosphorylated in the cytoplasm. Knockdown of YAP or inhibition of actin polymerization markedly impaired the EndMT in rBMECs. These findings suggest that ischemia-reperfusion increased intensity of FSS triggered an EndMT process and, thus, led to endothelial inflammation and tissue injury, whereas continuous FSS induced a time-dependent reversal MEndT event contributing to the endothelial repair. This study provides valuable insight for therapeutic strategies targeting IRI.

GPR55 Inactivation Diminishes Splenic Responses and Improves Neurological Outcomes in the Mouse Ischemia/Reperfusion Stroke Model

Although strokes are frequent and severe, treatment options are scarce. Plasminogen activators, the only FDA-approved agents for clot treatment (tissue plasminogen activators (tPAs)), are used in a limited patient group. Moreover, there are few approaches for handling the brain's inflammatory reactions to a stroke. The orphan G protein-coupled receptor 55 (GPR55)'s connection to inflammatory processes has been recently reported; however, its role in stroke remains to be discovered. Post-stroke neuroinflammation involves the central nervous system (CNS)'s resident microglia activation and the infiltration of leukocytes from circulation into the brain. Additionally, splenic responses have been shown to be detrimental to stroke recovery. While lymphocytes enter the brain in small numbers, they regularly emerge as a very influential leukocyte subset that causes secondary inflammatory cerebral damage. However, an understanding of how this limited lymphocyte presence profoundly impacts stroke outcomes remains largely unclear. In this study, a mouse model for transient middle cerebral artery occlusion (tMCAO) was used to mimic ischemia followed by a reperfusion (IS/R) stroke. GPR55 inactivation, with a potent GPR55-specific antagonist, ML-193, starting 6 h after tMCAO or the absence of the GPR55 in mice (GPR55 knock out (GPR55ko)) resulted in a reduced infarction volume, improved neurological outcomes, and decreased splenic responses. The inhibition of GPR55 with ML-193 diminished CD4+T-cell spleen egress and attenuated CD4+T-cell brain infiltration. Additionally, ML-193 treatment resulted in an augmented number of regulatory T cells (Tregs) in the brain post-tMCAO. Our report offers documentation and the functional evaluation of GPR55 in the brain-spleen axis and lays the foundation for refining therapeutics for patients after ischemic attacks.

Implications of Post-recanalization Perfusion Deficit After Acute Ischemic Stroke: a Scoping Review of Clinical and Preclinical Imaging Studies

The goal of reperfusion therapy for acute ischemic stroke (AIS) is to restore cerebral blood flow through recanalization of the occluded vessel. Unfortunately, successful recanalization does not always result in favorable clinical outcome. Post-recanalization perfusion deficits (PRPDs), constituted by cerebral hypo- or hyperperfusion, may contribute to lagging patient recovery rates, but its clinical significance remains unclear. This scoping review provides an overview of clinical and preclinical findings on post-ischemic reperfusion, aiming to elucidate the pattern and consequences of PRPD from a translational perspective. The MEDLINE database was searched for quantitative clinical and preclinical studies of AIS reporting PRPD based on cerebral circulation parameters acquired by translational tomographic imaging methods. PRPD and stroke outcome were mapped on a charting table, creating an overview of PRPD after AIS. Twenty-two clinical and twenty-two preclinical studies were included. Post-recanalization hypoperfusion is rarely reported in clinical studies (4/22) but unequivocally associated with detrimental outcome. Post-recanalization hyperperfusion is more commonly reported (18/22 clinical studies) and may be associated with positive or negative outcome. PRPD has been replicated in animal studies, offering mechanistic insights into causes and consequences of PRPD and allowing delineation of possible courses of PRPD. Complex relationships exist between PRPD and stroke outcome. Diversity in methods and lack of standardized definitions in reperfusion studies complicate the characterization of reperfusion patterns. Recommendations are made to advance the understanding of PRPD mechanisms and to further disentangle the relation between PRPD and disease outcome.

A narrative review of intravascular catheters in therapeutic hypothermia

Therapeutic hypothermia (TH) has been regarded as a promising neuroprotective method for acute ischemic stroke (AIS) for decades. During the development of TH, most researchers focused on improving hypothermic benefits by optimizing treatment processes and conditions. Intravenous thrombolysis and endovascular thrombectomy, for instance, have been introduced into AIS treatment. However, the lack of specialized intervention consumables, especially intervention catheter, led to inaccurate and uncontrolled hypothermic temperature, limited the efficacy of TH. In this review, intervention catheters as well as accessory equipment utilized in TH treatment has been summarized. Hopefully, this review may inspire the future development of TH specialized intervention catheter, enhance the outcome of TH, and neuroprotective efficacy in AIS.

Role of Microglia in Stroke

Ischemic stroke is a complex brain pathology caused by an interruption of blood supply to the brain. It results in neurological deficits which that reflect the localization and the size of the compromised brain area and are the manifestation of complex pathogenic events triggered by energy depletion. Inflammation plays a prominent role, worsening the injury in the early phase and influencing poststroke recovery in the late phase. Activated microglia are one of the most important cellular components of poststroke inflammation, appearing from the first few hours and persisting for days and weeks after stroke injury. In this chapter, we will discuss the nature of the inflammatory response in brain ischemia, the contribution of microglia to injury and regeneration after stroke, and finally, how ischemic stroke directly affects microglia functions and survival.

Lower Melatonin Indicates Poor Short-term Prognosis in Patients with Acute Ischemic Stroke

AIMS

We evaluated endogenous melatonin levels in the acute phase of cerebral infarction and explored the impact of possible changes in melatonin levels on the prognosis of patients.

METHODS

This study recruited acute ischemic stroke (AIS) patients from the Department of the Second Affiliated Hospital of Soochow University between December 2019 and June 2021, along with healthy control subjects. Salivary melatonin samples were collected from each participant between 7 pm and 10 pm, and fasting plasma was collected the following morning to measure the levels of inflammatory markers. The prognosis was assessed through follow-up three months after discharge. The relationship between melatonin levels and plasma inflammatory markers was assessed, followed by an analysis of the effect of melatonin levels on patient prognosis.

RESULTS

The study enrolled a total of 160 participants, including 120 AIS patients aged 50 years or older (61.7% male) and 40 age-matched controls (55.0% male). The AIS group exhibited lower salivary melatonin levels at 19 (P = 0.002), 20 (P < 0.001), 21 (P < 0.001), and 22 (P < 0.001) o'clock, and the average melatonin level was also lower (P < 0.001). Logistic regression analysis models indicated an association between low melatonin levels and poor prognosis. Salivary melatonin levels demonstrated good predictive ability for the prognosis of AIS patients.

CONCLUSION

Melatonin levels were lower in AIS patients compared to controls. In addition, lower melatonin levels were associated with a poorer prognosis among AIS patients.

Neuroprotective effects of ivermectin against transient cerebral ischemia-reperfusion in rats

Stroke is a leading cause of disability and death worldwide. Ivermectin is a broad-spectrum anti-parasitic agent with potential anti-bacterial, anti-viral, and anti-cancer effects. However, the effects of ivermectin on the brain are poorly described. This study examined the effects of ivermectin on cerebral ischemia-reperfusion (IR) in rats. A rat model of transient global IR was induced by bilateral carotid artery occlusion for 20 min. Rats received ivermectin (2 mg/kg/day, ip) one hour after inducing cerebral IR for three consecutive days at 24-h intervals. Next, we examined the effects of ivermectin on brain infarction, histopathology, malondialdehyde levels, myeloperoxidase activity, spatial learning and memory, and phospho-AMPK protein levels. The results showed that ivermectin reduced brain infarct size (P < 0.001) and histopathological changes such as cerebral leukocyte accumulation and edema (P < 0.05) compared to untreated rats with IR. Treatment with ivermectin also decreased myeloperoxidase activity (P < 0.01) and malondialdehyde levels (P < 0.05) while increasing AMPK activity (P < 0.001), memory, and learning compared to the untreated IR group. Overall, we show for the first time that ivermectin conferred neuroprotective effects in a rat model of cerebral IR. Our results indicate that three days of treatment with ivermectin reduced brain infarct size, lipid peroxidation, and myeloperoxidase activity and improved memory and learning in rats with cerebral IR. These effects likely occurred via AMPK-dependent mechanisms.

Predictors for hemorrhagic transformation and cerebral edema in stroke patients with first-pass complete recanalization

BACKGROUND

Predictors of radiological complications attributable to reperfusion injury remain unknown when baseline setting is optimal for endovascular treatment and procedural setting is the best in stroke patients with large vessel occlusion (LVO).

AIMS

To identify clinical and radiological/procedural predictors for hemorrhagic transformation (HT) and cerebral edema (CED) at 24 hr in patients obtaining complete recanalization in one pass of thrombectomy for ischemic stroke ⩽ 6 h from symptom onset with intra-cranial anterior circulation LVO and ASPECTS ⩾ 6.

METHODS

We conducted a cohort study on prospectively collected data from 1400 patients enrolled in the Italian Registry of Endovascular Treatment in Acute Stroke.

RESULTS

HT was reported in 248 (18%) patients and early CED was reported in 260 (19.2%) patients. In the logistic regression model including predictors from a first model with clinical variables and from a second model with radiological/procedural variables, diabetes mellitus (odds ratio (OR) = 1.832, 95% confidence interval (CI) = 1.201-2.795), higher National Institutes of Health Stroke Scale (NIHSS) (OR = 1.076, 95% CI = 1.044-1.110), lower Alberta Stroke Program Early CT (ASPECTS) (OR = 0.815, 95% CI = 0.694-0.957), and longer onset-to-groin time (OR = 1.005, 95% CI = 1.002-1.007) were predictors of HT, whereas general anesthesia was inversely associated with HT (OR = 0.540, 95% CI = 0.355-0.820). Higher NIHSS (OR = 1.049, 95% CI = 1.021-1.077), lower ASPECTS (OR = 0.700, 95% CI = 0.613-0.801), intravenous thrombolysis (OR = 1.464, 95% CI = 1.061-2.020), longer onset-to-groin time (OR = 1.002, 95% CI = 1.001-1.005), and longer procedure time (OR = 1.009, 95% CI = 1.004-1.015) were predictors of early CED. After repeating a fourth logistic regression model including also good collaterals, the same variables remained predictors for HT and/or early CED, except diabetes mellitus and thrombolysis, while good collaterals were inversely associated with early CED (OR = 0.385, 95% CI = 0.248-0.599).

CONCLUSIONS

Higher NIHSS, lower ASPECTS, and longer onset-to-groin time were predictors for both HT and early CED. General anesthesia and good collaterals were inversely associated with HT and early CED, respectively. Longer procedure time was predictor of early CED.

CD8+ T cells in brain injury and neurodegeneration

The interaction between the peripheral immune system and the brain is increasingly being recognized as an important layer of neuroimmune regulation and plays vital roles in brain homeostasis as well as neurological disorders. As an important population of T-cell lymphocytes, the roles of CD8+ T cells in infectious diseases and tumor immunity have been well established. Recently, increasing number of complex functions of CD8+ T cells in brain disorders have been revealed. However, an advanced summary and discussion of the functions and mechanisms of CD8+ T cells in brain injury and neurodegeneration are still lacking. Here, we described the differentiation and function of CD8+ T cells, reviewed the involvement of CD8+ T cells in the regulation of brain injury including stroke and traumatic brain injury and neurodegenerative diseases, such as Alzheimer's disease (AD) and Parkinson's disease (PD), and discussed therapeutic prospects and future study goals. Understanding these processes will promote the investigation of T-cell immunity in brain disorders and provide new intervention strategies for the treatment of brain injury and neurodegeneration.

The role and mechanisms of microvascular damage in the ischemic myocardium

Following myocardial ischemic injury, the most effective clinical intervention is timely restoration of blood perfusion to ischemic but viable myocardium to reduce irreversible myocardial necrosis, limit infarct size, and prevent cardiac insufficiency. However, reperfusion itself may exacerbate cell death and myocardial injury, a process commonly referred to as ischemia/reperfusion (I/R) injury, which primarily involves cardiomyocytes and cardiac microvascular endothelial cells (CMECs) and is characterized by myocardial stunning, microvascular damage (MVD), reperfusion arrhythmia, and lethal reperfusion injury. MVD caused by I/R has been a neglected problem compared to myocardial injury. Clinically, the incidence of microvascular angina and/or no-reflow due to ineffective coronary perfusion accounts for 5-50% in patients after acute revascularization. MVD limiting drug diffusion into injured myocardium, is strongly associated with the development of heart failure. CMECs account for > 60% of the cardiac cellular components, and their role in myocardial I/R injury cannot be ignored. There are many studies on microvascular obstruction, but few studies on microvascular leakage, which may be mainly due to the lack of corresponding detection methods. In this review, we summarize the clinical manifestations, related mechanisms of MVD during myocardial I/R, laboratory and clinical examination means, as well as the research progress on potential therapies for MVD in recent years. Better understanding the characteristics and risk factors of MVD in patients after hemodynamic reconstruction is of great significance for managing MVD, preventing heart failure and improving patient prognosis.

Unconventional T cells in brain homeostasis, injury and neurodegeneration

The interaction between peripheral immune cells and the brain is an important component of the neuroimmune axis. Unconventional T cells, which include natural killer T (NKT) cells, mucosal-associated invariant T (MAIT) cells, γδ T cells, and other poorly defined subsets, are a special group of T lymphocytes that recognize a wide range of nonpolymorphic ligands and are the connection between adaptive and innate immunity. Recently, an increasing number of complex functions of these unconventional T cells in brain homeostasis and various brain disorders have been revealed. In this review, we describe the classification and effector function of unconventional T cells, review the evidence for the involvement of unconventional T cells in the regulation of brain homeostasis, summarize the roles and mechanisms of unconventional T cells in the regulation of brain injury and neurodegeneration, and discuss immunotherapeutic potential as well as future research goals. Insight of these processes can shed light on the regulation of T cell immunity on brain homeostasis and diseases and provide new clues for therapeutic approaches targeting brain injury and neurodegeneration.

Intracerebral hirudin injection alleviates cognitive impairment and oxidative stress and promotes hippocampal neurogenesis in rats subjected to cerebral ischemia

Cerebral ischemia starts with cerebral blood flow interruption that causes severely limited oxygen and glucose supply, eliciting a cascade of pathological events, such as excitotoxicity, oxidative stress, calcium dysregulation, and inflammatory response, which could ultimately result in neuronal death. Hirudin has beneficial effects in ischemic stroke and possesses antioxidant and anti-inflammatory properties. Therefore, we investigated the biological functions of hirudin and its related mechanisms in cerebral ischemia. The ischemia-like conditions were induced by transient middle cerebral artery occlusion (MCAO). To investigate hirudin roles, intracerebroventricular injection of 10 U hirudin was given to the rats. Cognitive and motor functions were examined by beam walking and Morris water maze tests. 2,3,5-triphenyl tetrazolium chloride-stained brain sections were used to measure infarct volume. Oxidative stress was determined by assessment of oxidative stress markers. The proliferated cells were labeled by BrdU and Nestin double staining. Western blotting was performed to measure protein levels. Hirudin administration improved cognitive and motor deficits post-ischemia. Hirudin reduced brain infarction and neurological damage in MCAO-subjected rats. Hirudin alleviated oxidative stress and enhanced neurogenesis in ischemic rats. Hirudin facilitated the promotion of phosphorylation of extracellular signal-regulated kinase (ERK) 1/2 and serine-threonine kinase. In sum, hirudin alleviates cognitive deficits by attenuating oxidative stress and promoting hippocampal neurogenesis through the regulation of ERK1/2 and serine-threonine kinase in MCAO-subjected rats.

Neuroprotective effects of Coenzyme Q10 in ischemia-reperfusion injury via inflammation and oxidative stress reduction in adult male rats

This study aimed to investigate the potential neuroprotective effects of coenzyme Q10 in cerebral ischemia-reperfusion injury-induced neuronal damage and explore the underlying mechanisms. Twenty-eight adult male rats, weighing approximately 200-300 grams, were randomly divided into four groups: the sham group (neck dissection without ischemia), the control group (30 minutes of bilateral common carotid artery ligation followed by one hour of reperfusion), the vehicle group (oral carboxymethylcellulose solution for seven days prior to bilateral common carotid artery ligation and reperfusion), and the treatment group (seven days of coenzyme Q10 pretreatment followed by bilateral common carotid artery occlusion and reperfusion). Histopathological analysis and measurement of brain infarct size were performed, and cerebral levels of IL-6, IL-10, TNF-α, ICAM-1, NF-κB p65, and total antioxidant capacity were assessed. These cerebral tissue levels and cerebral infarct size were significantly elevated in the control and vehicle groups compared to the sham group. Conversely, the total antioxidant capacity was significantly reduced in these groups. Coenzyme Q10 treatment resulted in a significant increase in IL-10 and total antioxidant capacity levels, along with a significant decrease in IL-6, ICAM-1, TNF-α, and NF-κB p65 levels. Histopathological analysis revealed a significant reduction in ischemic damage in the coenzyme Q10-treated group. Coenzyme Q10 has neuroprotective properties in rats subjected to cerebral ischemia/reperfusion injury, possibly through its anti-inflammatory and anti-oxidative effects.

The Pathological Mechanism of Neuronal Autophagy-Lysosome Dysfunction After Ischemic Stroke

The abnormal initiation of autophagy flux in neurons after ischemic stroke caused dysfunction of autophagy-lysosome, which not only led to autophagy flux blockage, but also resulted in autophagic death of neurons. However, the pathological mechanism of neuronal autophagy-lysosome dysfunction did not form a unified viewpoint until now. In this review, taking the autophagy lysosomal dysfunction of neurons as a starting point, we summarized the molecular mechanisms that led to neuronal autophagy lysosomal dysfunction after ischemic stroke, which would provide theoretical basis for the clinical treatment of ischemic stroke.

Noninvasive In Vivo Thrombus Imaging in Patients With Ischemic Stroke or Transient Ischemic Attack-Brief Report

BACKGROUND

18F-GP1 is a novel positron-emitting radiotracer that is highly specific for activated platelets and thrombus. In a proof-of-concept study, we aimed to determine its potential clinical application in establishing the role and origin of thrombus in ischemic stroke.

METHODS

Eleven patients with recent ischemic stroke (n=9) or transient ischemic attack (n=2) underwent 18F-GP1 positron emission tomography and computed tomography angiography at a median of 11 (range, 2-21) days from symptom onset. 18F-GP1 uptake (maximum target-to-background ratio) was assessed in the carotid arteries and brain.

RESULTS

18F-GP1 uptake was identified in 10 of 11 patients: 4 in the carotid arteries only, 3 in the brain only, and 3 in both the brain and carotid arteries. In those with carotid uptake, 4 participants had >50% stenosis and 3 had nonstenotic disease. One case had bilateral stenotic disease (>70%), but only the culprit carotid artery demonstrated 18F-GP1 uptake. The average uptake was higher in the culprit (median maximum target-to-background ratio, 1.55 [interquartile range, 1.26-1.82]) compared with the contralateral nonculprit carotid artery (maximum target-to-background ratio, 1.22 [1.19-1.6]). In those with brain 18F-GP1 uptake (maximum target-to-background ratio, 6.45 [4.89-7.65]), areas of acute infarction on computed tomography correlated with brain 18F-GP1 uptake in 6 cases. Ex vivo autoradiography of postmortem infarcted brain tissue showed focal uptake corresponding to intraluminal thrombus within the culprit vessel and downstream microvasculature. There was also evidence of diffuse uptake within some of the infarcted brain tissue reflecting parenchymal petechial hemorrhage.

CONCLUSIONS

18F-GP1 positron emission tomography and computed tomography angiography is a novel noninvasive method of identifying in vivo cerebrovascular thrombosis, which holds major promise in understanding the role and origin of thrombosis in stroke.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03943966.

Mechanoresponsive Drug Delivery Systems for Vascular Diseases

Mechanoresponsive drug delivery systems (DDS) have emerged as promising candidates to improve the current effectiveness and lower the side effects typically associated with direct drug administration in the context of vascular diseases. Despite tremendous research efforts to date, designing drug delivery systems able to respond to mechanical stimuli to potentially treat these diseases is still in its infancy. By understanding relevant biological forces emerging in healthy and pathological vascular endothelium, it is believed that better-informed design strategies can be deduced for the fabrication of simple-to-complex macromolecular assemblies capable of sensing mechanical forces. These responsive systems are discussed through insights into essential parameter design (composition, size, shape, and aggregation state) , as well as their functionalization with (macro)molecules that are intrinsically mechanoresponsive (e.g., mechanosensitive ion channels and mechanophores). Mechanical forces, including the pathological shear stress and exogenous stimuli (e.g., ultrasound, magnetic fields), used for the activation of mechanoresponsive DDS are also introduced, followed by in vitro and in vivo experimental models used to investigate and validate such novel therapies. Overall, this review aims to propose a fresh perspective through identified challenges and proposed solutions that could be of benefit for the further development of this exciting field.

Development and characterization of transfontanelle photoacoustic imaging system for detection of intracranial hemorrhages and measurement of brain oxygenation: Ex-vivo

We have developed and optimized an imaging system to study and improve the detection of brain hemorrhage and to quantify oxygenation. Since this system is intended to be used for brain imaging in neonates through the skull opening, i.e., fontanelle, we called it, Transfontanelle Photoacoustic Imaging (TFPAI) system. The system is optimized in terms of optical and acoustic designs, thermal safety, and mechanical stability. The lower limit of quantification of TFPAI to detect the location of hemorrhage and its size is evaluated using in-vitro and ex-vivo experiments. The capability of TFPAI in measuring the tissue oxygenation and detection of vasogenic edema due to brain blood barrier disruption are demonstrated. The results obtained from our experimental evaluations strongly suggest the potential utility of TFPAI, as a portable imaging modality in the neonatal intensive care unit. Confirmation of these findings in-vivo could facilitate the translation of this promising technology to the clinic.

A network pharmacology approach to decipher the total flavonoid extract of Dracocephalum Moldavica L. in the treatment of cerebral ischemia- reperfusion injury

BACKGROUND AND OBJECTIVE

Cerebral ischemia-reperfusion injury (CIRI) is a major injury that seriously endangers human health and is characterized by high mortality and high disability. The total flavonoid extract of Dracocephalum moldavica L.(TFDM) in the treatment of CIRI has been proved by clinical practice. But the mechanism for the treatment of CIRI by TFDM has not been systematically revealed.

STUDY DESIGN AND METHODS

The active compounds contained in TFDM were screened by literature mining and pharmacokinetic parameters, and the targets related to CIRI were collected by searching Drugbank, Genecards and OMIM databases. Cytoscape software was used to construct the protein interaction network of TFDM for the prevention and treatment of CIRI. Geneontology and signal pathway enrichment were analyzed. The key target pathway network of TFDM compounds was constructed and verified by pharmacological experiment in vitro.

RESULTS

21 active components were screened, 158 potential drug targets for the prevention and treatment of CIRI were obtained, 53 main targets were further screened in the protein-protein interaction network, and 106 signal pathways, 76 biological processes, 26 cell components and 50 molecular functions were enriched (P<0.05). Through the compound-target-pathway network, the key compounds that play a role in the prevention and treatment of CIRI, such as acacetin, apigenin and other flavonoids, as well as the corresponding key targets and key signal pathways, such as AKT1, SRC and EGFR were obtained. TFDM significantly decreased LDH, MDA levels and increased the NO activity levels in CIRI. Further studies have shown that TFDM increases the number of SRC proteins, and TFDM also increases p-AKT/ AKT. Molecular docking results showed that acacetin-7-O (- 6''-acetyl) -glucopyranoside, acacetin7-O-β-D-glucopyranoside, apigenin-7-O-β-D-galactoside respectively had good affinity for SRC protein. Acacetin-7-O (- 6''-acetyl) -glucopyranoside,acacetin-7-O-β-D-glucuronide, acacetin7-O-β-D-glucopyranoside had good affinity for AKT1 protein, respectively.

CONCLUSION

Our research showed that TFDM had the characteristics of multi-component, multi-target and multi-channel in the treatment of CIRI. The potential mechanism may be associated with the following signaling pathways:1) the signaling pathways of VEGF/SRC, which promote angiogenesis, 2) the signaling pathways of PI3K/AKT, which inhibit apoptosis, and 3) acacetin-7-O (- 6''-acetyl) -glucopyranoside is expected to be used as a candidate monomer component for natural drugs for further development.

Ligustrazine Nanoparticle Hitchhiking on Neutrophils for Enhanced Therapy of Cerebral Ischemia-Reperfusion Injury

Ischemic stroke is a refractory disease that endangers human health and safety owing to cerebral ischemia. Brain ischemia induces a series of inflammatory reactions. Neutrophils migrate from the circulatory system to the site of cerebral ischemia and accumulate in large numbers at the site of inflammation across the blood-brain barrier. Therefore, hitchhiking on neutrophils to deliver drugs to ischemic brain sites could be an optimal strategy. Since the surface of neutrophils has a formyl peptide receptor (FPR), this work modifies a nanoplatform surface by the peptide cinnamyl-F-(D)L-F-(D)L-F (CFLFLF), which can specifically bind to the FPR receptor. After intravenous injection, the fabricated nanoparticles effectively adhered to the surface of neutrophils in peripheral blood mediated by FPR, thereby hitchhiking with neutrophils to achieve higher accumulation at the inflammatory site of cerebral ischemia. In addition, the nanoparticle shell is composed of a polymer with reactive oxygen species (ROS)-responsive bond breaking and is encased in ligustrazine, a natural product with neuroprotective properties. In conclusion, the strategy of hitching the delivered drugs to neutrophils in this study could improve drug enrichment in the brain, thereby providing a general delivery platform for ischemic stroke or other inflammation-related diseases.

Asialo-rhuEPO as a Potential Neuroprotectant for Ischemic Stroke Treatment

Neuroprotective drugs to protect the brain against cerebral ischemia and reperfusion (I/R) injury are urgently needed. Mammalian cell-produced recombinant human erythropoietin (rhuEPOM) has been demonstrated to have excellent neuroprotective functions in preclinical studies, but its neuroprotective properties could not be consistently translated in clinical trials. The clinical failure of rhuEPOM was thought to be mainly due to its erythropoietic activity-associated side effects. To exploit its tissue-protective property, various EPO derivatives with tissue-protective function only have been developed. Among them, asialo-rhuEPO, lacking terminal sialic acid residues, was shown to be neuroprotective but non-erythropoietic. Asialo-rhuEPO can be prepared by enzymatic removal of sialic acid residues from rhuEPOM (asialo-rhuEPOE) or by expressing human EPO gene in glycoengineered transgenic plants (asialo-rhuEPOP). Both types of asialo-rhuEPO, like rhuEPOM, displayed excellent neuroprotective effects by regulating multiple cellular pathways in cerebral I/R animal models. In this review, we describe the structure and properties of EPO and asialo-rhuEPO, summarize the progress on neuroprotective studies of asialo-rhuEPO and rhuEPOM, discuss potential reasons for the clinical failure of rhuEPOM with acute ischemic stroke patients, and advocate future studies needed to develop asialo-rhuEPO as a multimodal neuroprotectant for ischemic stroke treatment.

Integrative Analysis of Single-Cell and Bulk Sequencing Data Depicting the Expression and Function of P2ry12 in Microglia Post Ischemia-Reperfusion Injury

P2ry12 is a microglial marker gene. Recently, increasing evidence has demonstrated that its expression levels can vary in response to different CNS disorders and can affect microglial functions, such as polarization, plasticity, and migration. However, the expression and function of P2ry12 in microglia during ischemia-reperfusion injury (IRI) remain unclear. Here, we developed a computational method to obtain microglia-specific P2ry12 genes (MSPGs) using sequencing data associated with IRI. We evaluated the change in comprehensive expression levels of MSPGs during IRI and compared it to the expression of P2ry12 to determine similarity. Subsequently, the MSPGs were used to explore the P2ry12 functions in microglia through bioinformatics. Moreover, several animal experiments were also conducted to confirm the reliability of the results. The expression of P2ry12 was observed to decrease gradually within 24 h post injury. In response, microglia with reduced P2ry12 expression showed an increase in the expression of one receptor-encoding gene (Flt1) and three ligand-encoding genes (Nampt, Igf1, and Cxcl2). Furthermore, double-labeling immunofluorescence staining revealed that inhibition of P2ry12 blocked microglial migration towards vessels during IRI. Overall, we employ a combined computational and experimental approach to successfully explore P2ry12 expression and function in microglia during IRI.

POU Domain Class 2 Transcription Factor 2 Inhibits Ferroptosis in Cerebral Ischemia Reperfusion Injury by Activating Sestrin2

Cerebral ischemia reperfusion injury (CIRI) is the commonest cause of brain dysfunction. Up-regulation of POU domain class 2 transcription factor 2 (POU2F2) has been reported in patients with cerebral ischemia, while the role of POU2F2 in CIRI remains elusive. Middle cerebral artery occlusion/reperfusion (MCAO/R) in mice and oxygen and glucose deprivation/reperfusion (OGD/R) in mouse primary cortical neurons were used as models of CIRI injury in vivo and in vitro. Lentivirus-mediated POU2F2 knockdown further impaired CIRI induced by MCAO/R in mice, which was accompanied by increased-neurological deficits, cerebral infarct volume and neuronal loss. Our evidence suggested that POU2F2 deficiency deteriorated oxidative stress and ferroptosis according to the phenomenon such as the abatement of SOD, GSH, glutathione peroxidase 4 (GPX4) activity and accumulation of ROS, lipid ROS, 4-hydroxynonenal (4-HNE) and MDA. In vivo, primary cortical neurons with POU2F2 knockdown also showed worse neuronal damage, oxidative stress and ferroptosis. Sestrin2 (Sesn2) was reported as a neuroprotection gene and involved in ferroptosis mechanism. Up-regulation of Sesn2 was observed in the ischemic penumbra and OGD/R-induced neuronal cells. Further, we proved that POU2F2, as a transcription factor, could bind to Sesn2 promoter and positively regulate its expression. Sesn2 overexpression relieved oxidative stress and ferroptosis induced by POU2F2 knockdown in OGD/R-treated neurons. This research demonstrated that CIRI induced a compensatory increase of POU2F2 and Sesn2. Down-regulated POU2F2 exacerbated CIRI through the acceleration of oxidative stress and ferroptosis possibly by decreasing Sesn2 expression, which offers new sights into therapeutic mechanisms for CIRI.

Up-regulation of lncRNA NEAT1 in cerebral ischemic stroke promotes activation of astrocytes by modulation of miR-488-3p/RAC1

We aim to research the molecular mechanism of lncRNA NEAT1 in the activation of astrocytes in a cerebral ischemia-reperfusion injury model. Mouse model of cerebral ischemia-reperfusion injury was constructed, and shNEAT1 was transfected. The infarct area, brain water content, and neurological deficiency were detected. Immunofluorescence detection and fluorescence in situ hybridization (FISH) assay were processed to detect glial fibrillary acidic protein (GFAP) expression. Astrocyte cells were cultured for oxygen-glucose deprivation/re-oxygenation (OGD)/re-oxygenation model construction. After treatment by shNEAT1, miR-488-3p mimic, miR-488-3p inhibitor, Q-PCR assay, western blot and ELISA were undertaken to detect the expressions of NEAT1, miR-488-3p, RAC1, inflammatory cytokines, RAC1 and GFAP. Dual luciferase reporter assay and RNA-binding protein immunoprecipitation (RIP) assay were used to verify the binding of NEAT1, miR-488-3p and RAC1. The expression of NEAT1 in brain tissue was significantly higher than that in Sham operation group. Knockdown of NEAT1 inhibited the brain damage caused by middle cerebral artery occlusion (MCAO) treatment, reduced the inflammatory response, and suppressed the activation of astrocytes. By constructing an in vitro OGD/R cell model, it was found that NEAT1 knockdown also inhibited the activation of astrocytes caused by OGD/R. Knockdown of NEAT1 caused the up-regulation of miR-488-3p and the down-regulation of RAC1. Knockdown of miR-488-3p or over-expression of RAC1 reversed the inhibitory effect of shNEAT1 on OGD/R-induced astrocyte activation. Over-expression of NEAT1 in cerebral ischemic stroke promotes activation of astrocytes by modulation miR-488-3p/RAC1, which is proved in vitro. Our study may provide a new idea for the diagnosis and treatment of MCAO.

Apelin-13 prevents the effects of oxygen-glucose deprivation/reperfusion on bEnd.3 cells by inhibiting AKT-mTOR signaling

Autophagy plays works by degrading misfolded proteins and dysfunctional organelles and maintains intracellular homeostasis. Apelin-13 has been investigated as an agent that might protect the blood-brain barrier (BBB) from cerebral ischemia/reperfusion (I/R) injury. In this study, we examined whether apelin-13 protects cerebral microvascular endothelial cells, important components of the BBB, from I/R injury by regulating autophagy. To mimic I/R injury, the mouse cerebral microvascular endothelia l cell line bEnd 3 undergoes the process of oxygen and glucose deprivation and re feeding in the process of culture. Cell viability was detected using a commercial kit, and cell migration was monitored by in vitro scratch assay. The tight junction (TJ) proteins ZO-1 and occludin; the autophagy markers LC3 II, beclin 1, and p62; and components of the AKT-mTOR signaling pathway were detected by Western blotting and immunofluorescence. To confirm the role of autophagy in OGD/R and the protective effect of apelin-13, we treated the cells with 3-methyladenine (3-MA), a pharmacological inhibitor of autophagy. Our results demonstrated that OGD/R increased autophagic activity but decreased viability, abundance of TJs, and migration. Viability and TJ abundance were further reduced when the OGD/R group was treated with 3-MA. These results indicated that bEnd.3 upregulates autophagy to ameliorate the effects of OGD/R injury on viability and TJs, but that the autophagy induced by OGD/R alone is not sufficient to protect against the effect on cell migration. Treatment of OGD/R samples with apelin-13 markedly increased viability, TJ abundance, and migration, as well as autophagic activity, whereas 3-MA inhibited this increase, suggesting that apelin-13 exerted its protective effects by upregulating autophagy.

Analysis of hippocampus in rats with acute brain ischemia-reperfusion injury treated with leuprolide acetate, an agonist of GnRH

BACKGROUND

The hippocampus is highly vulnerable to damage in the brain ischemia-reperfusion injury model. Leuprolide acetate has been shown to promote neurological recovery after injury in various regions of the central nervous system.

OBJECTIVE

The objective of this study was to assess the histology of the hippocampus and the expression of neuronal recovery markers, specifically the 200 kDa neurofilaments and the myelin basic protein, in rats with brain ischemia-reperfusion injury treated with leuprolide acetate.

METHODS

The rats were divided into three groups: Sham, ischemia-reperfusion with saline solution, and ischemia-reperfusion treated with leuprolide acetate. Coronal brain slices were obtained and stained with hematoxylin-eosin. The histological analysis involved quantifying the number of neurons in the hippocampal regions CA1, CA3 and DG. The myelin basic protein and neurofilaments were quantified using western blot.

RESULTS

The number of neurons in CA1 and DG was significantly higher in the leuprolide acetate group compared to the untreated group. Additionally, the expression of neurofilament and myelin basic protein markers was significantly increased in rats treated with leuprolide acetate compared to the untreated rats.

CONCLUSIONS

Leuprolide acetate promotes the recovery of hippocampal neurons in an acute brain ischemia-reperfusion injury model. These findings suggest that leuprolide acetate could be a potential therapeutic intervention for reversing damage in hippocampal ischemic lesions.

Sevoflurane postconditioning ameliorates cerebral ischemia-reperfusion injury in rats via TLR4/MyD88/TRAF6 signaling pathway

To determine whether sevoflurane postconditioning protects against cerebral ischemia reperfusion (I/R) injury and its potential mechanism, we employed bioinformatic analysis, neurological assessments, and western blot analysis, as well as triphenyl tetrazolium chloride, hematoxylin and eosin, Nissl, and immunofluorescence staining. We identified 103 differentially expressed genes induced by cerebral I/R, including 75 upregulated genes and 28 downregulated genes enriched for certain biological processes (involving regulation of inflammatory responses, cellular responses to interleukin 1, and chemokine activity) and signaling pathways (such as transcriptional misregulation in cancer, interleukin-17 signaling, rheumatoid arthritis, MAPK signaling, and Toll-like receptor signaling). As a typical path in Toll-like receptor signaling pathway, in the current study, we investigated the protective effect of sevoflurane postconditioning in cerebral I/R rats and further explore the role of TLR4/MyD88/TRAF6 signaling pathway in it. The results showed cerebral I/R-induced neurological deficits were comparatively less severe following sevoflurane postconditioning. In addition, TLR4/MyD88/TRAF6 signaling pathway-related proteins and neuropathic damage were ameliorated in aged rats following sevoflurane postconditioning, while the TLR4 agonist lipopolysaccharide aggravated these changes. Together, these findings suggest that sevoflurane postconditioning ameliorates cerebral I/R injury by a mechanism involving inhibition of the TLR4/MyD88/TRAF6 signaling pathway to suppress neuroinflammatory responses.

Wasp venom from Vespa magnifica acts as a neuroprotective agent to alleviate neuronal damage after stroke in rats

CONTEXT

Acute ischaemic stroke (AIS) is a major cause of disability and death, which is a serious threat to human health and life. Wasp venom extracted from Vespa magnifica Smith (Vespidae) could treat major neurological disorders.

OBJECTIVE

This study investigated the effects of wasp venom on AIS in rats.

MATERIAL AND METHODS

We used a transient middle cerebral artery occlusion (MCAO) model in Sprague-Dawley rats (260-280 g, n = 8-15) with a sham operation group being treated as negative control. MCAO rats were treated with wasp venom (0.05, 0.2 and 0.6 mg/kg, i.p.) using intraperitoneal injection. After treatment 48 h, behavioural tests, cortical blood flow (CBF), TTC staining, H&E staining, Nissl staining, TUNEL assay, immunohistochemistry (IHC) and ELISA were employed to investigate neuroprotective effects of wasp venom.

RESULTS

Compared with the MCAO group, wasp venom (0.6 mg/kg) improved neurological impairment, accelerated CBF recovery (205.6 ± 52.92 versus 216.7 ± 34.56), reduced infarct volume (337.1 ± 113.2 versus 140.7 ± 98.03) as well as BBB permeability as evidenced by changes in claudin-5 and AQP4. In addition, function recovery of stroke by wasp venom treatment was associated with a decrease in TNF-α, IL-1β, IL-6 and inhibition activated microglia as well as apoptosis. Simultaneously, the wasp venom regulated the angiogenesis factors VEGF and b-FGF in the brain.

CONCLUSIONS

Wasp venom exhibited a potential neuroprotective effect for AIS. In the future, we will focus on determining whether the observed actions were due to a single compound or the interaction of multiple components of the venom.