Targeting neutrophils in ischemic stroke: translational insights from experimental studies

CKLF1 in cardiovascular and cerebrovascular diseases

Chemokine like factor 1 (CKLF1) is a novel atypical chemokine, playing a crucial role in cardiovascular and cerebrovascular diseases (CCVDs) demonstrated by a growing body of works. In cardiovascular diseases including atherosclerosis and myocardial infarction, meanwhile in cerebrovascular diseases such as ischemic stroke and hemorrhagic stroke, the expression levels of CKLF1 change markedly, which triggers downstream signaling pathways by binding with its functional receptors, and then exerts multiple effects to participate in the occurrence and development of these CCVDs. The functional roles of CKLF1 are dynamic and CKLF1 may act as a double-edged sword. The CCVDs-promoting role is related to recruiting inflammatory cells, enhancing the proliferation of vascular smooth muscle cells and endothelial cells, while the CCVDs-suppressing role may correlate with migration of nerve cells and promotion of hematopoietic stem cell proliferation which contributes to disease recovery. Based on this, the paper intends to review expression shifts, potential roles, and molecular mechanisms of CKLF1 in CCVDs, and the current status of CKLF1 targeted therapeutic strategies is also included. We hope this review may provide a valuable reference for using CKLF1 as a diagnostic and prognostic biomarker for CCVDs or developing novel treatments.

Sepsis compromises post-ischemic stroke neurological recovery and is associated with sex differences

AIMS

Infection is a complication after stroke and outcomes vary by sex. Thus, we investigated if sepsis affects brain from ischemic stroke and sex involvement.

MAIN METHODS

Male and female Wistar rats, were submitted to middle cerebral artery occlusion (MCAO) and after 7 days sepsis to cecal ligation and perforation (CLP). Infarct size, neuroinflammation, oxidative stress, and mitochondrial activity were quantified 24 h after CLP in the prefrontal cortex and hippocampus. Survival and neurological score were assessed up to 15 days after MCAO or 8 days after CLP (starting at 2 h after MCAO) and memory at the end.

KEY FINDINGS

CLP decreased survival, increased neurological impairments in MCAO females. Early, in male sepsis following MCAO led to increased glial activation in the brain structures, and increased TNF-α and IL-1β in the hippocampus. All groups had higher IL-6 in both tissues, but the hippocampus had lower IL-10. CLP potentiated myeloperoxidase (MPO) in the prefrontal cortex of MCAO male and female. In MCAO+CLP, only male increased MPO and nitrite/nitrate in hippocampus. Males in all groups had protein oxidation in the prefrontal cortex, but only MCAO+CLP in the hippocampus. Catalase decreased in the prefrontal cortex and hippocampus of all males and females, and MCAO+CLP only increased this activity in males. Female MCAO+CLP had higher prefrontal cortex complex activity than males. In MCAO+CLP-induced long-term memory impairment only in females.

SIGNIFICANCE

The parameters evaluated for early sepsis after ischemic stroke show a worse outcome for males, while females are affected during long-term follow-up.

Mechanistic insights into Lipocalin-2 in ischemic stroke and hemorrhagic brain injury: Integrating animal and clinical studies

Brain injuries, including strokes and traumatic brain injuries (TBI), are a major global health concern, contributing significantly to both mortality and long-term disability. Recent research has identified lipocalin-2 (LCN2), a glycoprotein secreted by various brain cells, as a key factor in influencing brain injury outcomes. Evidence from animal and clinical studies firmly establishes the pivotal role of LCN2 in driving the inflammatory responses triggered by damage to brain tissue. Furthermore, increased LCN2 promotes cellular differentiation, blood-brain barrier breakdown, and decreases cell viability. Interventions with LCN2 inhibitors attenuated brain injury through a reduction in the inflammation process and enhanced cellular viability. Potential mechanisms of LCN2 involve several pathways including the Janus kinase-2 (JAK2)-signal transducers and the transcription-3 (STAT3) signaling, hypoxia-inducible factor 1-alpha (HIF-1α)-LCN2-vascular endothelial growth factor alpha (VEGFα), and the PKR-like ER kinase (PERK) pathways. LCN2 itself interacts with diverse inflammatory cytokines in TBI and intracranial hemorrhage (ICH), resulting in disruption of the blood-brain barrier, increased programmed cell death, and an imbalance in iron homeostasis. Clinical studies have also shown that increased LCN2 level can act as a prognostic biomarker of outcomes following brain injuries. Therefore, this review aims to comprehensively evaluate the role and underlying mechanisms of LCN2 in brain injuries, including stroke and TBI, and explore potential therapeutic interventions targeting LCN2 in these conditions.

DNMT3A dysfunction promotes neuroinflammation and exacerbates acute ischemic stroke

Somatic mutations related to clonal hematopoiesis of indeterminate potential (CHIP) are risk factors for stroke. The impact of DNMT3A, the most mutated gene in CHIP, on clinical functional outcomes of acute ischemic stroke (AIS) remains unclear. In a well-characterized cohort of 8524 ischemic stroke patients, we demonstrated that DNMT3A-driven CHIP was significantly associated with neurological disability in these patients. With a stroke mouse model of transient middle cerebral artery occlusion (tMCAO), we demonstrated that DNMT3A protein levels in the brain penumbra increased. The DNMT3A inhibitor RG108 administration amplified neutrophil proliferation in the blood, promoted neutrophil infiltration into the brain penumbra, and exaggerated proinflammatory activation in tMCAO male mice. DNMT3A inhibition also significantly increased infarct volume and worsened neurobehavioral function in tMCAO male mice. In conclusion, DNMT3A somatic mutations are associated with worsened neurological disability in some patients with AIS, potentially through increased neutrophil proliferation and infiltration in the ischemic brain region. These findings suggest a possible mechanism for proinflammatory activation and tissue damage in the affected brain tissue, highlighting the need for further research in this area.

Alteration of N6-methyladenosine modification profiles in the neutrophilic RNAs following ischemic stroke

BACKGROUND

N6-methyladenosine (m6A) is one of the most extensive RNA methylation modifications in eukaryotes and participates in the pathogenesis of numerous diseases including ischemic stroke. Peripheral blood neutrophils are forerunners after ischemic brain injury and exert crucial functions. This study aims to explore the transcriptional profiles of m6A modification in neutrophils of patients with ischemic stroke.

RESULTS

We found that the expression levels of m6A regulators FTO and YTHDC1 were notably decreased in the neutrophils following ischemic stroke, and FTO expression was negatively correlated with neutrophil counts and neutrophil-to-lymphocyte ratio (NLR). The m6A mRNA&lncRNA epigenetic transcriptome microarray identified 416 significantly upregulated and 500 significantly downregulated mRNA peaks in neutrophils of ischemic stroke patients. Moreover, 48 mRNAs and 18 lncRNAs were hypermethylated, and 115 mRNAs and 29 lncRNAs were hypomethylated after cerebral ischemia. Gene ontology (GO) analysis identified that these m6A-modified mRNAs were primarily enriched in calcium ion transport, long-term synaptic potentiation, and base-excision repair. The signaling pathways involved were EGFR tyrosine kinase inhibitor resistance, ErbB, and base excision repair signaling pathway. MeRIP-qPCR validation results showed that NRG1 and GDPD1 were significantly hypermethylated, and LIG1, CHRND, lncRNA RP11-442J17.2, and lncRNA RP11-600P1.2 were significantly hypomethylated after cerebral ischemia. Moreover, the expression levels of major m6A regulators Mettl3, Fto, Ythdf1, and Ythdf3 were obviously declined in the brain and leukocytes of post-stroke mouse models.

CONCLUSION

This study explored the RNA m6A methylation pattern in the neutrophils of ischemic stroke patients, indicating that it is an intervention target of epigenetic regulation in ischemic stroke.

Postoperative neutrophil-to-lymphocyte ratio predicts malignant cerebral edema following endovascular treatment for acute ischemic stroke

Background and purpose

Malignant cerebral edema (MCE) is one of serious complications with high mortality following endovascular treatment (EVT) for acute ischemic stroke (AIS) with large vessel occlusion. We aimed to investigate the relationship between postoperative neutrophil-to-lymphocyte ratio (NLR) and MCE after EVT.

Methods

The clinical and imaging data of 175 patients with AIS of anterior circulation after EVT were studied. Admission and postoperative NLR were determined. The presence of MCE was evaluated on the computed tomography performed 24 h following EVT. The clinical outcomes were measured using the modified Rankin Scale (mRS) at 90-day after onset. Univariate and multivariate regression analyses were used to analyze the relationship between postoperative NLR and MCE. Optimal cutoff values of postoperative NLR to predict MCE were defined using receiver operating characteristic analysis.

Results

MCE was observed in 24% of the patients who underwent EVT and was associated with a lower rate of favorable clinical outcomes at 90-day. Multivariate logistic regression analysis demonstrated that baseline Alberta Stroke Program Early CT Score (ASPECT) score (OR = 0.614, 95% CI 0.502-0.750, p = 0.001), serum glucose (OR = 1.181, 95% CI 1.015-1.374, p = 0.031), and postoperative NLR (OR = 1.043, 95% CI 1.002-1.086, p = 0.041) were independently associated with MCE following EVT for AIS with large vessel occlusion. Postoperative NLR had an area under the receiver operating characteristic curve of 0.743 for prediction MCE, and the optimal cutoff value was 6.15, with a sensitivity and specificity of 86.8% and 55%.

Conclusion

Elevated postoperative NLR is independently associated with malignant brain edema following EVT for AIS with large vessel occlusion, and may serve as an early predictive indicator for MCE after EVT.

Exacerbation of thromboinflammation by JAK2V617F mutation worsens the prognosis of cerebral venous sinus thrombosis

ABSTRACT

Cerebral venous sinus thrombosis (CVST) is an uncommon venous thromboembolic event accounting for <1% of strokes resulting in brain parenchymal injuries. JAK2V617F mutation, the most frequent driving mutation of myeloproliferative neoplasms, has been reported to be associated with worse clinical outcomes in patients with CVST. We investigated whether hematopoietic JAK2V617F expression predisposes to specific pathophysiological processes and/or worse prognosis after CVST. Using an in vivo mouse model of CVST, we analyzed clinical, biological, and imaging outcomes in mice with hematopoietic-restricted Jak2V617F expression, compared with wild-type Jak2 mice. In parallel, we studied a human cohort of JAK2V617F-positive or -negative CVST. Early after CVST, mice with hematopoietic Jak2V617F expression had increased adhesion of platelets and neutrophils in cerebral veins located in the vicinity of CVST. On day 1, Jak2V617F mice had a worse outcome characterized by significantly more frequent and severe intracranial hemorrhages (ICHs) and higher mortality rates. Peripheral neutrophil activation was enhanced, as indicated by higher circulating platelet-neutrophil aggregates, upregulated CD11b expression, and higher myeloperoxydase plasma level. Concurrently, immunohistological and brain homogenate analysis showed higher neutrophil infiltration and increased blood-brain barrier disruption. Similarly, patients with JAK2V617F-positive CVST tended to present higher thrombotic burden and had significantly higher systemic immune-inflammation index, a systemic thromboinflammatory marker, than patients who were JAK2V617F-negative. In mice with CVST, our study corroborates that Jak2V617F mutation leads to a specific pattern including increased thrombotic burden, ICH, and mortality. The exacerbated thromboinflammatory response, observed both in mice and patients positive for JAK2V617F, could contribute to hemorrhagic complications.

Characterization of the Components and Metabolites of Achyranthes Bidentata in the Plasma and Brain Tissue of Rats Based on Ultrahigh Performance Liquid Chromatography-High-Resolution Mass Spectrometry (UHPLC-HR-MS)

BACKGROUND

Achyranthes bidentata (AR) is a traditional Chinese herb used for the treatment of hypertension and cerebral ischemia, but its pharmacological effects are not known.

AIM OF STUDY

We aimed to detect and accurately identify the components and metabolites of AR in the plasma and brain tissue of Sprague Dawley rats.

METHODS

We employed ultrahigh performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HR-MS) to detect AR components in the plasma and brain tissue of rats. The absorption and metabolites in the plasma and brain tissue of normal control rats and rats that underwent middle cerebral artery occlusion (MCAO) were characterized and compared.

RESULTS

A total of 281 compounds, including alkaloids, flavonoids, terpenoids, phenylpropanes, sugars and glycosides, steroids, triterpenes, amino acids, and peptides, was identified in samples of Achyranthes bidentata (TCM-AR). Four types of absorbable prototype components and 48 kinds of metabolites were identified in rats in the normal control plasma group which were given AR (AR plasma group), and five kinds of metabolites were identified in rats of the normal control brain tissue group which were given AR (AR brain group). Three absorbed prototype components and 13 metabolites were identified in the plasma of rats which underwent MCAO and were given AR (MCAO + AR plasma group). Six absorbed prototype components and two metabolites were identified in the brain tissue of rats who underwent MCAO and were administered AR (MCAO + AR brain group). These results showed that, after the oral administration of AR, the number of identified components in plasma was more than that in brain tissue. The number of prototype components in the AR plasma group was higher than that in the MCAO + AR plasma group, which may indicate that metabolite absorption in rats undergoing MCAO was worse. The number of prototype components in the MCAO + AR brain group was higher than that in the AR brain group, indicating that the blood-brain barrier was destroyed after MCAO, resulting in more compounds entering brain tissue.

CONCLUSIONS

UHPLC-HR-MS was used to rapidly analyze the components and metabolites of AR in the blood and brain of rats under normal and pathologic conditions, and to comprehensively characterize the components of TCM-AR. We also analyzed and compared the absorbable components and metabolites of normal rats under cerebral ischemia-reperfusion injury to explore the potential mechanism of action. This method could be applied to various Chinese herbs and disease models, which could promote TCM modernization.

Circulating Chemokines and Short- and Long-Term Outcomes After Ischemic Stroke

Chemokines are vital in post-cerebral ischemia inflammatory reactions. We investigate the possible relationship between plasma chemokines and short-term and long-term outcomes after stroke. This study included 235 patients (median age, 72 years; 49.8% female) suffering from ischemic stroke, or transient ischemic attack admitted to the hospital within 24 h of onset. We evaluated chemokines CCL2, CCL5, CXCL8, CXCL9, and CXCL10 in plasma samples collected upon admission. Further, we assessed functional outcomes at 3- and 12-months, all-cause fatality over 5 years, and episodes of delirium within the first 7 days of admission. Multivariate analysis revealed an association between higher CXCL10 levels and an increased risk of poor functional outcomes at 3 months (OR: 3.02, 95%CI: 1.22-7.46, p = 0.016) and 12 months (OR: 2.32, 95%CI: 1.03-5.26, p = 0.043), as well as an increased death risk (HR: 1.79, 95%CI: 1.04-3.07, p = 0.036). High CXCL8 levels independently predicted poor functional outcomes at 12 months (OR: 2.69, 95%CI: 1.39-6.31, p = 0.005) and a higher 5-year case fatality rate (HR: 1.90, 95%CI: 1.23-2.93, p = 0.004). Elevated CXCL9 levels also predicted unfavourable functional outcomes at 12 months (OR: 2.45, 95%CI: 1.07-5.61, p = 0.034). In univariate analysis, increased levels of CXCL8, CXCL9, and CXCL10 showed an association with delirium, although this link was not evident in the multivariate analysis. Plasma CXCL8 and CXCL10 show potential as prognostic biomarkers for stroke outcomes and as therapeutic targets suitable for reverse translation.

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.

Systemic biomarker associated with poor outcome after futile reperfusion

BACKGROUND

Successful recanalization does not lead to complete tissue reperfusion in a considerable percentage of ischemic stroke patients. This study aimed to identify biomarkers associated with futile recanalization. Leukoaraiosis predicts poor outcomes of this phenomenon. Soluble tumour necrosis factor-like weak inducer of apoptosis (sTWEAK), which is associated with leukoaraiosis degrees, could be a potential biomarker.

METHODS

This study includes two cohorts of ischemic stroke patients in a multicentre retrospective observational study. Effective reperfusion, defined as a reduction of ≥8 points in the National Institutes of Health Stroke Scale (NIHSS) within the first 24 h, was used as a clinical marker of effective reperfusion.

RESULTS

In the first cohort study, female sex, age, and high NIHSS at admission (44.7% vs. 81.1%, 71.3 ± 13.7 vs. 81.1 ± 6.7; 16 [13, 21] vs. 23 [17, 28] respectively; p < .0001) were confirmed as predictors of futile recanalization. ROC curve analysis showed that leukocyte levels (sensitivity of 99%, specificity of 55%) and sTWEAK level (sensitivity of 92%, specificity of 88%) can discriminate between poor and good outcomes. Both biomarkers simultaneously are higher associated with outcome after effective reperfusion (OR: 2.17; CI 95% 1.63-4.19; p < .0001) than individually (leukocytes OR: 1.38; CI 95% 1.00-1.64, p = .042; sTWEAK OR: 1.00; C I95% 1.00-1.01, p = .019). These results were validated using a second cohort, where leukocytes and sTWEAK showed a sensitivity of 100% and specificity of 66.7% and 75% respectively.

CONCLUSIONS

Leukocyte and sTWEAK could be biomarkers of reperfusion failure and subsequent poor outcomes. Further studies will be necessary to explore its role in reperfusion processes.

Dietary vitamin B6 intake and stroke are negatively associated in adults: A cross-sectional study from the NHANES

Background

The relationship between dietary vitamin B6 and stroke risk is controversial; thus, we analyzed their correlation using data from the National Health and Nutrition Examination Survey (NHANES).

Method

Data from 2005 to 2018 were collected from the NHANES database. Two 24-h dietary recalls and a standard questionnaire were used to evaluate vitamin B6 intake and stroke prevalence. We used logistic regression models to estimate the association between dietary vitamin B6 intake and stroke risk and investigated the nonlinear relationship between them using a restricted cubic spline (RCS). Sensitivity analysis was conducted using propensity score matching (PSM).

Results

Among 24,214 participants, 921 were patients diagnosed with stroke, while 23,293 were without stroke. The multivariate logistic regression model revealed that individuals in the highest quartile of vitamin B6 consumption had a significantly lower stroke risk than those in the lowest quartile under the fully adjusted model (OR: 0.48, 95 % CI: 0.35-0.66, P < 0.001). Subgroup analyses showed that dietary intake of vitamin B6 was a significant protective factor against stroke risk in different populations, with the most pronounced effect in the population engaging in moderate-intensity physical activity (OR: 0.34, 95%CI: 0.20-0.57). The RCS models revealed a non-linear L-shaped relationship (P for nonlinearity = 0.006) between stroke and dietary intake of vitamin B6.

Conclusions

Our study shows that an increased intake of vitamin B6 could be an effective strategy in reducing the risk of stroke.

Relationship between thrombus vWF and NETs with clinical severity and peripheral blood immunocytes' indicators in patients with acute ischemic stroke

OBJECTIVE

To investigate the association between von Willebrand factor (vWF) and neutrophil extracellular traps (NETs) in thrombus with clinical severity and peripheral blood immunocytes' indicators in patients with early-stage acute ischemic stroke (AIS).

METHODS

A retrospective study was conducted using the clinical data of 66 patients with AIS who underwent endovascular mechanical thrombectomy and had their thrombus samples collected. The concentrations of vWF and NETs in the thrombus samples were quantitatively assessed. Peripheral blood samples taken in the early stages of the disease were analyzed for total white blood cell counts (WBC), ratios of neutrophils (NEU%), lymphocytes (LYM%), eosinophils (EOS%), and monocytes (MONO%). The severity of clinical symptoms in these patients was evaluated using the modified Rankin Scale (mRS), Essen Stroke Risk Score (ESRS), Barthel Index (BI), and National Institute of Health Stroke Scale (NIHSS).

RESULTS

Higher vWF levels in thrombus were associated with lower NIHSS scores, while higher NETs levels were associated with higher initial NIHSS scores. In the early stages of AIS, WBC count and vWF levels were negatively correlated, as well as NEU%. LYM% was positively correlated with vWF level; however, it was negatively correlated with NETs. EOS% was positively correlated with vWF levels.

CONCLUSION

In the early stages of AIS, a higher peripheral WBC count and NEU%, combined with decreased EOS% and LYM%, were significantly correlated with a lower vWF level in the thrombus, potentially indicating more severe symptoms. Consequently, the timely administration of vWF-targeted medications is recommended for such patients. Reduced LYM% is indicative of elevated NETs levels and correlated with more severe clinical symptoms. Therefore, the prompt initiation of NETs-targeted medication is warranted for these patients.

Application and advances of biomimetic membrane materials in central nervous system disorders

Central nervous system (CNS) diseases encompass spinal cord injuries, brain tumors, neurodegenerative diseases, and ischemic strokes. Recently, there has been a growing global recognition of CNS disorders as a leading cause of disability and death in humans and the second most common cause of death worldwide. The global burdens and treatment challenges posed by CNS disorders are particularly significant in the context of a rapidly expanding global population and aging demographics. The blood-brain barrier (BBB) presents a challenge for effective drug delivery in CNS disorders, as conventional drugs often have limited penetration into the brain. Advances in biomimetic membrane nanomaterials technology have shown promise in enhancing drug delivery for various CNS disorders, leveraging properties such as natural biological surfaces, high biocompatibility and biosafety. This review discusses recent developments in biomimetic membrane materials, summarizes the types and preparation methods of these materials, analyzes their applications in treating CNS injuries, and provides insights into the future prospects and limitations of biomimetic membrane materials.

Transcriptome Analysis Reveals Dynamic Microglial-Induced A1 Astrocyte Reactivity via C3/C3aR/NF-κB Signaling After Ischemic Stroke

Microglia and astrocytes are key players in neuroinflammation and ischemic stroke. A1 astrocytes are a subtype of astrocytes that are extremely neurotoxic and quickly kill neurons. Although the detrimental A1 astrocytes are present in many neurodegenerative diseases and are considered to accelerate neurodegeneration, their role in the pathophysiology of ischemic stroke is poorly understood. Here, we combined RNA-seq, molecular and immunological techniques, and behavioral tests to investigate the role of A1 astrocytes in the pathophysiology of ischemic stroke. We found that astrocyte phenotypes change from a beneficial A2 type in the acute phase to a detrimental A1 type in the chronic phase following ischemic stroke. The activated microglial IL1α, TNF, and C1q prompt commitment of A1 astrocytes. Inhibition of A1 astrocytes induction attenuates reactive gliosis and ameliorates morphological and functional defects following ischemic stroke. The crosstalk between astrocytic C3 and microglial C3aR contributes to the formation of A1 astrocytes and morphological and functional defects. In addition, NF-κB is activated following ischemic stroke and governs the formation of A1 astrocytes via direct targeting of inflammatory cytokines and chemokines. Taken together, we discovered that A2 astrocytes and A1 astrocytes are enriched in the acute and chronic phases of ischemic stroke respectively, and that the C3/C3aR/NF-κB signaling leads to A1 astrocytes induction. Therefore, the C3/C3aR/NF-κB signaling is a novel therapeutic target for ischemic stroke treatment.

Pannexin1 Channel-Mediated Inflammation in Acute Ischemic Stroke

Emerging evidence suggests that inflammation mediated by the pannexin1 channel contributes significantly to acute ischemic stroke. It is believed that the pannexin1 channel is key in initiating central system inflammation during the early stages of acute ischemic stroke. Moreover, the pannexin1 channel is involved in the inflammatory cascade to maintain the inflammation levels. Specifically, the interaction of pannexin1 channels with ATP-sensitive P2X7 purinoceptors or promotion of potassium efflux mediates the activation of the NLRP3 inflammasome, triggering the release of pro-inflammatory factors such as IL-1 and IL-18, exacerbating and sustaining inflammation of brain. Also, increased release of ATP induced by cerebrovascular injury activates pannexin1 in vascular endothelial cells. This signal directs peripheral leukocytes to migrate into ischemic brain tissue, leading to an expansion of the inflammatory zone. Intervention strategies targeting pannexin1 channels may greatly alleviate inflammation after acute ischemic stroke to improve this patient population's clinical outcomes. In this review, we sought to summarize relevant studies on inflammation mediated by the pannexin1 channel in acute ischemic stroke and discussed the possibility of using brain organoid-on-a-chip technology to screen miRNAs that exclusively target the pannexin1 channel to provide new therapeutic measures for targeted regulation of pannexin1 channel to reduce inflammation in acute ischemic stroke.

The immunomodulatory mechanism of acupuncture treatment for ischemic stroke: research progress, prospects, and future direction

Ischemic stroke (IS) is one of the leading causes of death and disability. Complicated mechanisms are involved in the pathogenesis of IS. Immunomodulatory mechanisms are crucial to IS. Acupuncture is a traditional non-drug treatment that has been extensively used to treat IS. The exploration of neuroimmune modulation will broaden the understanding of the mechanisms underlying acupuncture treatment. This review summarizes the immune response of immune cells, immune cytokines, and immune organs after an IS. The immunomodulatory mechanisms of acupuncture treatment on the central nervous system and peripheral immunity, as well as the factors that influence the effects of acupuncture treatment, were summarized. We suggest prospects and future directions for research on immunomodulatory mechanisms of acupuncture treatment for IS based on current progress, and we hope that these will provide inspiration for researchers. Additionally, acupuncture has shown favorable outcomes in the treatment of immune-based nervous system diseases, generating new directions for research on possible targets and treatments for immune-based nervous system diseases.

Convergence of nanomedicine and neutrophils for drug delivery

Neutrophils have recently emerged as promising carriers for drug delivery due to their unique properties including rapid response toward inflammation, chemotaxis, and transmigration. When integrated with nanotechnology that has enormous advantages in improving treatment efficacy and reducing side effects, neutrophil-based nano-drug delivery systems have expanded the repertoire of nanoparticles employed in precise therapeutic interventions by either coating nanoparticles with their membranes, loading nanoparticles inside living cells, or engineering chimeric antigen receptor (CAR)-neutrophils. These neutrophil-inspired therapies have shown superior biocompatibility, targeting ability, and therapeutic robustness. In this review, we summarized the benefits of combining neutrophils and nanotechnologies, the design principles and underlying mechanisms, and various applications in disease treatments. The challenges and prospects for neutrophil-based drug delivery systems were also discussed.

Neutrophil Membrane-Camouflaged Polyprodrug Nanomedicine for Inflammation Suppression in Ischemic Stroke Therapy

Neuroinflammation has emerged as a major concern in ischemic stroke therapy because it exacebates neurological dysfunction and suppresses neurological recovery after ischemia/reperfusion. Fingolimod hydrochloride (FTY720) is an FDA-approved anti-inflammatory drug which exhibits potential neuroprotective effects in ischemic brain parenchyma. However, delivering a sufficient amount of FTY720 through the blood-brain barrier into brain lesions without inducing severe cardiovascular side effects remains challenging. Here, a neutrophil membrane-camouflaged polyprodrug nanomedicine that can migrate into ischemic brain tissues and in situ release FTY720 in response to elevated levels of reactive oxygen species. This nanomedicine delivers 15.2-fold more FTY720 into the ischemic brain and significantly reduces the risk of cardiotoxicity and infection compared with intravenously administered free drug. In addition, single-cell RNA-sequencing analysis identifies that the nanomedicine attenuates poststroke inflammation by reprogramming microglia toward anti-inflammatory phenotypes, which is realized via modulating Cebpb-regulated activation of NLRP3 inflammasomes and secretion of CXCL2 chemokine. This study offers new insights into the design and fabrication of polyprodrug nanomedicines for effective suppression of inflammation in ischemic stroke therapy.

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.

Fibrinogen deposition promotes neuroinflammation and fibrin-derived γ377-395 peptide ameliorates neurological deficits after ischemic stroke

BACKGROUND

Fibrin(ogen) deposition in the central nervous system (CNS) contributes to neuropathological injury; however, its role in ischemic stroke is unknown. In this study, we identified fibrinogen as a novel proinflammatory regulator of post-stroke neuroinflammation and revealed the neuro-protection effect of fibrin-derived γ377-395peptide in stroke.

METHODS

Fibrinogen depletion and fibrinogen-derived γ377-395peptide treatment were performed 2 h after establishing a permanent middle cerebral artery occlusion (pMCAO) model. The infarction volume, neurological score, fibrin(ogen) deposition, and inflammatory response were evaluated 24 h after occlusion. Both in vivo and in vitro studies were conducted to assess the therapeutic potential of the γ377-395peptide in blocking the interactions between fibrin(ogen) and neutrophils.

RESULTS

Fibrin(ogen) deposited in the infarct core promoted post-stroke inflammation and exacerbated neurological deficits in the acute phase after stroke onset. Reducing fibrinogen deposition resulted in a decrease in infarction volume, improved neurological scores, and reduced inflammation in the brain. Additionally, the presence of neutrophil accumulation near fibrin(ogen) deposits was observed in ischemic lesions, and the engagement of fibrin(ogen) by integrin receptor αMβ2 promoted neutrophil activation and post-stroke inflammation. Finally, inhibiting fibrin(ogen)-mediated neutrophil activation using a fibrinogen-derived γ377-395peptide significantly attenuated neurological deficits.

CONCLUSIONS

Fibrin(ogen) is a crucial regulator of post-stroke inflammation and contributes to secondary brain injury. The inflammation induced by fibrin(ogen) is primarily driven by neutrophils during acute ischemic stroke and can be ameliorated using the fibrin-derived γ377-395peptide. Targeting the fibrin(ogen)-mediated neuropathological process represents a promising approach for neuroprotective therapy after stroke while preserving its beneficial coagulation function.

Discovery and validation of molecular patterns and immune characteristics in the peripheral blood of ischemic stroke patients

Background

Stroke is a disease with high morbidity, disability, and mortality. Immune factors play a crucial role in the occurrence of ischemic stroke (IS), but their exact mechanism is not clear. This study aims to identify possible immunological mechanisms by recognizing immune-related biomarkers and evaluating the infiltration pattern of immune cells.

Methods

We downloaded datasets of IS patients from GEO, applied R language to discover differentially expressed genes, and elucidated their biological functions using GO, KEGG analysis, and GSEA analysis. The hub genes were then obtained using two machine learning algorithms (least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE)) and the immune cell infiltration pattern was revealed by CIBERSORT. Gene-drug target networks and mRNA-miRNA-lncRNA regulatory networks were constructed using Cytoscape. Finally, we used RT-qPCR to validate the hub genes and applied logistic regression methods to build diagnostic models validated with ROC curves.

Results

We screened 188 differentially expressed genes whose functional analysis was enriched to multiple immune-related pathways. Six hub genes (ANTXR2, BAZ2B, C5AR1, PDK4, PPIH, and STK3) were identified using LASSO and SVM-RFE. ANTXR2, BAZ2B, C5AR1, PDK4, and STK3 were positively correlated with neutrophils and gamma delta T cells, and negatively correlated with T follicular helper cells and CD8, while PPIH showed the exact opposite trend. Immune infiltration indicated increased activity of monocytes, macrophages M0, neutrophils, and mast cells, and decreased infiltration of T follicular helper cells and CD8 in the IS group. The ceRNA network consisted of 306 miRNA-mRNA interacting pairs and 285 miRNA-lncRNA interacting pairs. RT-qPCR results indicated that the expression levels of BAZ2B, C5AR1, PDK4, and STK3 were significantly increased in patients with IS. Finally, we developed a diagnostic model based on these four genes. The AUC value of the model was verified to be 0.999 in the training set and 0.940 in the validation set.

Conclusion

Our research explored the immune-related gene expression modules and provided a specific basis for further study of immunomodulatory therapy of IS.

Targeting brain-peripheral immune responses for secondary brain injury after ischemic and hemorrhagic stroke

The notion that the central nervous system is an immunologically immune-exempt organ has changed over the past two decades, with increasing evidence of strong links and interactions between the central nervous system and the peripheral immune system, both in the healthy state and after ischemic and hemorrhagic stroke. Although primary injury after stroke is certainly important, the limited therapeutic efficacy, poor neurological prognosis and high mortality have led researchers to realize that secondary injury and damage may also play important roles in influencing long-term neurological prognosis and mortality and that the neuroinflammatory process in secondary injury is one of the most important influences on disease progression. Here, we summarize the interactions of the central nervous system with the peripheral immune system after ischemic and hemorrhagic stroke, in particular, how the central nervous system activates and recruits peripheral immune components, and we review recent advances in corresponding therapeutic approaches and clinical studies, emphasizing the importance of the role of the peripheral immune system in ischemic and hemorrhagic stroke.

Bioinformatics-driven identification and validation of diagnostic biomarkers for cerebral ischemia reperfusion injury

Objective

This article aims to identify genetic features associated with immune cell infiltration in cerebral ischemia-reperfusion injury (CIRI) development through bioinformatics, with the goal of discovering diagnostic biomarkers and potential therapeutic targets.

Methods

We obtained two datasets from the Gene Expression Omnibus (GEO) database to identify immune-related differentially expressed genes (IRDEGs). These genes' functions were analyzed via Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG). Tools such as CIBERSORT and ssGSEA assessed immune cell infiltration. The Starbase and miRDB databases predicted miRNAs interacting with hub genes, and Cytoscape software mapped mRNA-miRNA interaction networks. The ENCORI database was employed to predict RNA binding proteins interacting with hub genes. Key genes were identified using a random forest algorithm and constructing a Support Vector Machine (SVM) model. LASSO regression analysis constructed a diagnostic model for hub genes to determine their diagnostic value, and PCR analysis validated their expression in cerebral ischemia-reperfusion.

Results

We identified 10 IRDEGs (C1qa, Ccl4, Cd74, Cd8a, Cxcl10, Gmfg, Grp, Lgals3bp, Timp1, Vim). The random forest algorithm, and SVM model intersection revealed three key genes (Ccl4, Gmfg, C1qa) as diagnostic biomarkers for CIRI. LASSO regression analysis, further refined this to two key genes (Ccl4 and C1qa), With ROC curve, analysis confirming their diagnostic efficacy (C1qa AUC = 0.75, Ccl4 AUC = 0.939). PCR analysis corroborated these findings.

Conclusions

Our study elucidates immune and metabolic response mechanisms in CIRI, identifying two immune-related genes as key biomarkers and potential therapeutic targets in response to cerebral ischemia-reperfusion injury.

Machine learning identifies novel coagulation genes as diagnostic and immunological biomarkers in ischemic stroke

BACKGROUND

Coagulation system is currently known associated with the development of ischemic stroke (IS). Thus, the current study is designed to identify diagnostic value of coagulation genes (CGs) in IS and to explore their role in the immune microenvironment of IS.

METHODS

Aberrant expressed CGs in IS were input into unsupervised consensus clustering to classify IS subtypes. Meanwhile, key CGs involved in IS were further selected by weighted gene co-expression network analysis (WGCNA) and machine learning methods, including random forest (RF), support vector machine (SVM), generalized linear model (GLM) and extreme-gradient boosting (XGB). The diagnostic performance of key CGs were evaluated by receiver operating characteristic (ROC) curves. At last, quantitative PCR (qPCR) was performed to validate the expressions of key CGs in IS.

RESULTS

IS patients were classified into two subtypes with different immune microenvironments by aberrant expressed CGs. Further WGCNA, machine learning methods and ROC curves identified ACTN1, F5, TLN1, JMJD1C and WAS as potential diagnostic biomarkers of IS. In addition, their expressions were significantly correlated with macrophages, neutrophils and/or T cells. GSEA also revealed that those biomarkers may regulate IS via immune and inflammation. Moreover, qPCR verified the expressions of ACTN1, F5 and JMJD1C in IS.

CONCLUSIONS

The current study identified ACTN1, F5 and JMJD1C as novel coagulation-related biomarkers associated with IS immune microenvironment, which enriches our knowledge of coagulation-mediated pathogenesis of IS and sheds light on next-step in vivo and in vitro experiments to elucidate the relevant molecular mechanisms.

Neutrophil extracellular traps correlate with severity and prognosis in patients with ischemic stroke: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

A correlation between neutrophil extracellular traps (NETs) and ischemic stroke (IS) has been hypothesized, but the results of relevant studies remain controversial. The purpose was to determine whether NETs have an impact on ischemic stroke.

METHODS

The studies on the correlation between NETs and IS were retrieved from CNKI, Wanfang Data, VIP, CBM, PubMed, Web of Science, Embase, and Cochrane databases by computer from the start of the database to December 2022. The study adhered to PRISMA guidelines. The PICOS model was used to create inclusion criteria. Two researchers screened the literature and extracted the relevant data. The quality of the included studies was evaluated using the NOS and the 11 items recommended by the AHRQ, and meta-analysis was completed using Stata 15.1 software.

RESULTS

The researchers included 752 patients in 7 studies (4 case-control studies and 3 cross-sectional studies). The meta-analysis found NETs are positively associated with the severity of IS at the time of onset [r(95% CI) = 0.31(0.24, 0.38), P < 0.001]. NETs are positively associated with a worse prognosis of IS [r(95% CI) = 0.34(0.13, 0.53), P = 0.003].

CONCLUSION

The presence of NETs is positively related to the severity and prognosis of IS. Higher levels of NETs indicate a more severe disease and a poorer prognosis. Because the number and quality of included studies are limited, the above results must be supported by further high-quality studies.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/ , identifier: CRD42022356619.

Atomic force microscopy in disease-related studies: Exploring tissue and cell mechanics

Despite significant progress in human medicine, certain diseases remain challenging to promptly diagnose and treat. Hence, the imperative lies in the development of more exhaustive criteria and tools. Tissue and cellular mechanics exhibit distinctive traits in both normal and pathological states, suggesting that "force" represents a promising and distinctive target for disease diagnosis and treatment. Atomic force microscopy (AFM) holds great promise as a prospective clinical medical device due to its capability to concurrently assess surface morphology and mechanical characteristics of biological specimens within a physiological setting. This review presents a comprehensive examination of the operational principles of AFM and diverse mechanical models, focusing on its applications in investigating tissue and cellular mechanics associated with prevalent diseases. The findings from these studies lay a solid groundwork for potential clinical implementations of AFM. RESEARCH HIGHLIGHTS: By examining the surface morphology and assessing tissue and cellular mechanics of biological specimens in a physiological setting, AFM shows promise as a clinical device to diagnose and treat challenging diseases.

FOXO1 reshapes neutrophils to aggravate acute brain damage and promote late depression after traumatic brain injury

BACKGROUND

Neutrophils are traditionally viewed as first responders but have a short onset of action in response to traumatic brain injury (TBI). However, the heterogeneity, multifunctionality, and time-dependent modulation of brain damage and outcome mediated by neutrophils after TBI remain poorly understood.

METHODS

Using the combined single-cell transcriptomics, metabolomics, and proteomics analysis from TBI patients and the TBI mouse model, we investigate a novel neutrophil phenotype and its associated effects on TBI outcome by neurological deficit scoring and behavioral tests. We also characterized the underlying mechanisms both in vitro and in vivo through molecular simulations, signaling detections, gene expression regulation assessments [including dual-luciferase reporter and chromatin immunoprecipitation (ChIP) assays], primary cultures or co-cultures of neutrophils and oligodendrocytes, intracellular iron, and lipid hydroperoxide concentration measurements, as well as forkhead box protein O1 (FOXO1) conditional knockout mice.

RESULTS

We identified that high expression of the FOXO1 protein was induced in neutrophils after TBI both in TBI patients and the TBI mouse model. Infiltration of these FOXO1high neutrophils in the brain was detected not only in the acute phase but also in the chronic phase post-TBI, aggravating acute brain inflammatory damage and promoting late TBI-induced depression. In the acute stage, FOXO1 upregulated cytoplasmic Versican (VCAN) to interact with the apoptosis regulator B-cell lymphoma-2 (BCL-2)-associated X protein (BAX), suppressing the mitochondrial translocation of BAX, which mediated the antiapoptotic effect companied with enhancing interleukin-6 (IL-6) production of FOXO1high neutrophils. In the chronic stage, the "FOXO1-transferrin receptor (TFRC)" mechanism contributes to FOXO1high neutrophil ferroptosis, disturbing the iron homeostasis of oligodendrocytes and inducing a reduction in myelin basic protein, which contributes to the progression of late depression after TBI.

CONCLUSIONS

FOXO1high neutrophils represent a novel neutrophil phenotype that emerges in response to acute and chronic TBI, which provides insight into the heterogeneity, reprogramming activity, and versatility of neutrophils in TBI.

The role of oxidative stress in blood-brain barrier disruption during ischemic stroke: Antioxidants in clinical trials

Ischemic stroke is one of the leading causes of death and disability. Occlusion and reperfusion of cerebral blood vessels (i.e., ischemia/reperfusion (I/R) injury) generates reactive oxygen species (ROS) that contribute to brain cell death and dysfunction of the blood-brain barrier (BBB) via oxidative stress. BBB disruption influences the pathogenesis of ischemic stroke by contributing to cerebral edema, hemorrhagic transformation, and extravasation of circulating neurotoxic proteins. An improved understanding of mechanisms for ROS-associated alterations in BBB function during ischemia/reperfusion (I/R) injury can lead to improved treatment paradigms for ischemic stroke. Unfortunately, progress in developing ROS targeted therapeutics that are effective for stroke treatment has been slow. Here, we review how ROS are produced in response to I/R injury, their effects on BBB integrity (i.e., tight junction protein complexes, transporters), and the utilization of antioxidant treatments in ischemic stroke clinical trials. Overall, knowledge in this area provides a strong translational framework for discovery of novel drugs for stroke and/or improved strategies to mitigate I/R injury in stroke patients.

Immune cells: potential carriers or agents for drug delivery to the central nervous system

Drug delivery systems (DDS) have recently emerged as a promising approach for the unique advantages of drug protection and targeted delivery. However, the access of nanoparticles/drugs to the central nervous system (CNS) remains a challenge mainly due to the obstruction from brain barriers. Immune cells infiltrating the CNS in the pathological state have inspired the development of strategies for CNS foundation drug delivery. Herein, we outline the three major brain barriers in the CNS and the mechanisms by which immune cells migrate across the blood-brain barrier. We subsequently review biomimetic strategies utilizing immune cell-based nanoparticles for the delivery of nanoparticles/drugs to the CNS, as well as recent progress in rationally engineering immune cell-based DDS for CNS diseases. Finally, we discuss the challenges and opportunities of immune cell-based DDS in CNS diseases to promote their clinical development.

Inflammation biomarkers in the intracranial blood are associated with outcome in patients with ischemic stroke

BACKGROUND

Performing endovascular treatment (EVT) in patients with acute ischemic stroke (AIS) allows a port of entry for intracranial biological sampling.

OBJECTIVE

To test the hypothesis that specific immune players are molecular contributors to disease, outcome biomarkers, and potential targets for modifying AIS.

METHODS

We examined 75 subjects presenting with large vessel occlusion of the anterior circulation and undergoing EVT. Intracranial blood samples were obtained by microcatheter aspiration, as positioned for stent deployment. Peripheral blood samples were collected from the femoral artery. Plasma samples were quality controlled by electrophoresis and analyzed using a Mesoscale multiplex for targeted inflammatory and vascular factors.

RESULTS

We measured 37 protein biomarkers in our sample cohort. Through multivariate analysis, adjusted for age, intravenous thrombolysis, pretreatment National Institutes of Health Stroke Scale and Alberta Stroke Program Early CT scores, we found that post-clot blood levels of interleukin-6 (IL-6) were significantly correlated (adjusted P value <0.05) with disability assessed by the modified Rankin Scale (mRS) score at 90 days, with medium effect size. Chemokine (C-C) ligand 17 CCL17/TARC levels were inversely correlated with the mRS score. Examination of peripheral blood showed that these correlations did not reach statistical significance after correction. Intracranial biomarker IL-6 level was specifically associated with a lower likelihood of favorable outcome, defined as a mRS score of 0-2.

CONCLUSIONS

Our findings show a signature of blood inflammatory factors at the cerebrovascular occlusion site. The correlations between these acute-stage biomarkers and mRS score outcome support an avenue for add-on and localized immune modulatory strategies in AIS.

Endothelial peroxiredoxin-4 is indispensable for blood-brain barrier integrity and long-term functional recovery after ischemic stroke

The endothelial lining of cerebral microvessels is damaged relatively early after cerebral ischemia/reperfusion (I/R) injury and mediates blood-brain barrier (BBB) disruption, neurovascular injury, and long-term neurological deficits. I/R induces BBB leakage within 1 h due to subtle structural alterations in endothelial cells (ECs), including reorganization of the actin cytoskeleton and subcellular redistribution of junctional proteins. Herein, we show that the protein peroxiredoxin-4 (Prx4) is an endogenous protectant against endothelial dysfunction and BBB damage in a murine I/R model. We observed a transient upregulation of Prx4 in brain ECs 6 h after I/R in wild-type (WT) mice, whereas tamoxifen-induced, selective knockout of Prx4 from endothelial cells (eKO) mice dramatically raised vulnerability to I/R. Specifically, eKO mice displayed more BBB damage than WT mice within 1 to 24 h after I/R and worse long-term neurological deficits and focal brain atrophy by 35 d. Conversely, endothelium-targeted transgenic (eTG) mice overexpressing Prx4 were resistant to I/R-induced early BBB damage and had better long-term functional outcomes. As demonstrated in cultures of human brain endothelial cells and in animal models of I/R, Prx4 suppresses actin polymerization and stress fiber formation in brain ECs, at least in part by inhibiting phosphorylation/activation of myosin light chain. The latter cascade prevents redistribution of junctional proteins and BBB leakage under conditions of Prx4 repletion. Prx4 also tempers microvascular inflammation and infiltration of destructive neutrophils and proinflammatory macrophages into the brain parenchyma after I/R. Thus, the evidence supports an indispensable role for endothelial Prx4 in safeguarding the BBB and promoting functional recovery after I/R brain injury.

Cell Membrane Camouflaged Biomimetic Nanoparticles as a Versatile Platform for Brain Diseases Treatment

Although there are various advancements in biomedical in the past few decades, there are still challenges in the treatment of brain diseases. The main difficulties are the inability to deliver a therapeutic dose of the drug to the brain through the blood-brain barrier (BBB) and the serious side effects of the drug. Thus, it is essential to select biocompatible drug carriers and novel therapeutic tools to better enhance the effect of brain disease treatment. In recent years, biomimetic nanoparticles (BNPs) based on natural cell membranes, which have excellent biocompatibility and low immunogenicity, are widely used in the treatment of brain diseases to enable the drug to successfully cross the BBB and target brain lesions. BNPs can prolong the circulation time in vivo, are more conducive to drug aggregation in brain lesions. Cell membranes (CMs) from cancer cells (CCs), red blood cells (RBCs), white blood cells (WBCs), and so on are used as biomimetic coatings for nanoparticles (NPs) to achieve the ability to target, evade clearance, or stimulate the immune system. This review summarizes the application of different cell sources as BNPs coatings in the treatment of brain diseases and discusses the possibilities and challenges of clinical translation.

Upregulation of TRPC1 in microglia promotes neutrophil infiltration after ischemic stroke

Neutrophil infiltration has been linked to worse clinical outcomes after ischemic stroke. Microglia, a key type of immune-competent cell, engage in cross-talk with the infiltrating immune cells in the inflamed brain area, yet the molecular mechanisms involved remain largely unexplored. In this study, we investigated the mechanisms of how canonical transient receptor potential 1 (TRPC1) modulated neutrophil infiltration in male mouse cerebral ischemia and reperfusion injury (CIRI) models. Our findings revealed a notable upregulation of TRPC1 in microglia within both middle cerebral artery occlusion reperfusion (MCAO/R) and in vitro oxygen-glucose deprivation/regeneration (OGD/R) model. Conditional Trpc1 knockdown in microglia markedly reduced infarct volumes and alleviated neurological deficits. Microglia conditional Trpc1 knockdown mice displayed less neutrophil infiltration in peri-infarct area. Trpc1 knockdown microglia exhibited a reduced primed proinflammatory phenotype with less secretion of CC-Chemokines ligand (CCL) 5 and CCL2 after MCAO/R. Blocking CCL5/2 significantly mitigated neutrophil infiltration in microglia/neutrophil transwell co-culture system upon OGD/R condition. Trpc1 knockdown markedly reduced store-operated calcium entry and nuclear factor of activated T-cells c1 (NFATc1) level in OGD/R treated microglia. Overexpression of Nfatc1 reversed the CCL5/2 reducing effect of Trpc1 knockdown, which is mediated by small interfering RNA in BV2 cells upon OGD/R. Our data indicate that upregulation of TRPC1 in microglia stimulates the production of CCL5/2 through the Ca2+/NFATc1 pathway. Upregulated CCL5/2 leads to an increase in neutrophil infiltration into the brain, thereby aggravating reperfusion injury. Our results demonstrate the importance of TRPC1 in microglia-mediated neuroinflammation and suggest a potential means for reducing CIRI induced neurological injury.

Myeloid cells in vascular dementia and Alzheimer's disease: Possible therapeutic targets?

Growing evidence supports the suggestion that the peripheral immune system plays a role in different pathologies associated with cognitive impairment, such as vascular dementia (VD) or Alzheimer's disease (AD). The aim of this review is to summarize, within the peripheral immune system, the implications of different types of myeloid cells in AD and VD, with a special focus on post-stroke cognitive impairment and dementia (PSCID). We will review the contributions of the myeloid lineage, from peripheral cells (neutrophils, platelets, monocytes and monocyte-derived macrophages) to central nervous system (CNS)-associated cells (perivascular macrophages and microglia). Finally, we will evaluate different potential strategies for pharmacological modulation of pathological processes mediated by myeloid cell subsets, with an emphasis on neutrophils, their interaction with platelets and the process of immunothrombosis that triggers neutrophil-dependent capillary stall and hypoperfusion, as possible effector mechanisms that may pave the way to novel therapeutic avenues to stop dementia, the epidemic of our time. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.

The Relevance of Reperfusion Stroke Therapy for miR-9-3p and miR-9-5p Expression in Acute Stroke-A Preliminary Study

Reperfusion stroke therapy is a modern treatment that involves thrombolysis and the mechanical removal of thrombus from the extracranial and/or cerebral arteries, thereby increasing penumbra reperfusion. After reperfusion therapy, 46% of patients are able to live independently 3 months after stroke onset. MicroRNAs (miRNAs) are essential regulators in the development of cerebral ischemia/reperfusion injury and the efficacy of the applied treatment. The first aim of this study was to examine the change in serum miRNA levels via next-generation sequencing (NGS) 10 days after the onset of acute stroke and reperfusion treatment. Next, the predictive values of the bioinformatics analysis of miRNA gene targets for the assessment of brain ischemic response to reperfusion treatment were explored. Human serum samples were collected from patients on days 1 and 10 after stroke onset and reperfusion treatment. The samples were subjected to NGS and then validated using qRT-PCR. Differentially expressed miRNAs (DEmiRNAs) were used for enrichment analysis. Hsa-miR-9-3p and hsa-miR-9-5p expression were downregulated on day 10 compared to reperfusion treatment on day 1 after stroke. The functional analysis of miRNA target genes revealed a strong association between the identified miRNA and stroke-related biological processes related to neuroregeneration signaling pathways. Hsa-miR-9-3p and hsa-miR-9-5p are potential candidates for the further exploration of reperfusion treatment efficacy in stroke patients.

Assessing the predictive value of neutrophil percentage to albumin ratio for ICU admission in ischemic stroke patients

Background

Acute ischemic stroke (AIS) remains a substantial global health challenge, contributing to increased morbidity, disability, and mortality. This study aimed at investigating the predictive value of the neutrophil percentage to albumin ratio (NPAR) in determining intensive care unit (ICU) admission among AIS patients.

Methods

A retrospective observational study was conducted, involving AIS cases admitted to a tertiary hospital in Jordan between 2015 and 2020. Lab data were collected upon admission, and the primary outcome was ICU admission during hospitalization. Descriptive and inferential analyses were performed using SPSS version 29.

Results

In this study involving 364 AIS patients, a subset of 77 (21.2%) required admission to the ICU during their hospital stay, most frequently within the first week of admission. Univariable analysis revealed significantly higher NPAR levels in ICU-admitted ischemic stroke patients compared to those who were not admitted (23.3 vs. 15.7, p < 0.001), and multivariable regression models confirmed that higher NPAR (≥19.107) independently predicted ICU admission in ischemic stroke patients (adjusted odds ratio [aOR] = 4.85, 95% CI: 1.83-12.83). Additionally, lower GCS scores and higher neutrophil-to-lymphocyte ratio (NLR) were also associated with increased likelihood of ICU admission. In terms of predictive performance, NPAR showed the highest accuracy with an AUC of 0.885, sensitivity of 0.805, and specificity of 0.854, using a cutoff value of 19.107. NPAR exhibits an AUC of 0.058, significantly outperforming NLR (Z = 2.782, p = 0.005).

Conclusion

NPAR emerged as a robust independent predictor of ICU admission in ischemic stroke patients, surpassing the predictive performance of the NLR.

Hyperglycemia exacerbates cerebral ischemia/reperfusion injury by up-regulating autophagy through p53-Sesn2-AMPK pathway

Hyperglycemia exacerbates ischemic brain injury by up-regulating autophagy. However, the underlying mechanisms are unknown. This study aims to determine whether hyperglycemia activates autophagy through the p53-Sesn2-AMPK signaling pathway. Rats were subjected to 30-min middle cerebral artery occlusion (MCAO) with reperfusion for 1- and 3-day under normo- and hyperglycemic conditions; and HT22 cells were exposed to oxygen deprivation (OG) or oxygen-glucose deprivation and re-oxygenation (OGD/R) with high glucose. Autophagy inhibitors, 3-MA and ARI, were used both in vivo and in vitro. The results showed that, compared with the normoglycemia group (NG), hyperglycemia (HG) increased infarct volume and apoptosis in penumbra area, worsened neurological deficit, and augmented autophagy. after MCAO followed by 1-day reperfusion. Further, HG promoted the conversion of LC-3I to LC-3II, decreased p62, increased protein levels of aldose reductase, p53, P-p53ser15, Sesn2, AMPK and numbers of autophagosomes and autolysosomes, detected by transmission electron microscopy and mRFP-GFP-LC3 molecular probe, in the cerebral cortex after ischemia and reperfusion injury in animals or in cultured HT22 cells exposed to hypoxia with high glucose content. Finally, experiments with autophagy inhibitors 3-MA and aldose reductase inhibitor (ARI) revealed that while both inhibitors reduced the number of TUNEL positive neurons and reversed the effects of hyperglycemic ischemia on LC3 and p62, only ARI decreased the levels of p53, P-p53ser15. These results suggested that hyperglycemia might induce excessive autophagy to aggravate the brain injury resulted from I/R and that hyperglycemia might activate the p53-Sesn2-AMPK signaling pathway, in addition to the classical PI3K/AKT/mTOR autophagy pathway.

Machine learning predictors of risk of death within 7 days in patients with non-traumatic subarachnoid hemorrhage in the intensive care unit: A multicenter retrospective study

Non-traumatic subarachnoid hemorrhage (SAH) is a critical neurosurgical emergency with a high mortality rate, imposing a significant burden on both society and families. Accurate prediction of the risk of death within 7 days in SAH patients can provide valuable information for clinicians, enabling them to make better-informed medical decisions. In this study, we developed six machine learning models using the MIMIC III database and data collected at our institution. These models include Logistic Regression (LR), AdaBoosting (AB), Multilayer Perceptron (MLP), Bagging (BAG), Gradient Boosting Machines (GBM), and Extreme Gradient Boosting (XGB). The primary objective was to identify predictors of death within 7 days in SAH patients admitted to intensive care units. We employed univariate and multivariate logistic regression as well as Pearson correlation analysis to screen the clinical variables of the patients. The initially screened variables were then incorporated into the machine learning models, and the performance of these models was evaluated. Furthermore, we compared the performance differences among the six models and found that the MLP model exhibited the highest performance with an AUC of 0.913. In this study, we conducted risk factor analysis using Shapley values to identify the factors associated with death within 7 days in patients with SAH. The risk factors we identified include Gcsmotor, bicarbonate, wbc, spo2, heartrate, age, nely, glucose, aniongap, GCS, rbc, sysbp, sodium, and gcseys. To provide clinicians with a useful tool for assessing the risk of death within 7 days in SAH patients, we developed a web calculator based on the MLP machine learning model.

Mechanisms of immune response and cell death in ischemic stroke and their regulation by natural compounds

Ischemic stroke (IS), which is the third foremost cause of disability and death worldwide, has inflammation and cell death as its main pathological features. IS can lead to neuronal cell death and release factors such as damage-related molecular patterns, stimulating the immune system to release inflammatory mediators, thereby resulting in inflammation and exacerbating brain damage. Currently, there are a limited number of treatment methods for IS, which is a fact necessitating the discovery of new treatment targets. For this review, current research on inflammation and cell death in ischemic stroke was summarized. The complex roles and pathways of the principal immune cells (microglia, astrocyte, neutrophils, T lymphocytes, and monocytes/macrophage) in the immune system after IS in inflammation are discussed. The mechanisms of immune cell interactions and the cytokines involved in these interactions are summarized. Moreover, the cell death mechanisms (pyroptosis, apoptosis, necroptosis, PANoptosis, and ferroptosis) and pathways after IS are explored. Finally, a summary is provided of the mechanism of action of natural pharmacological active ingredients in the treatment of IS. Despite significant recent progress in research on IS, there remain many challenges that need to be overcome.

Leukocyte differential gene expression prognostic value for high versus low seizure frequency in temporal lobe epilepsy

BACKGROUND

This study was performed to test the hypothesis that systemic leukocyte gene expression has prognostic value differentiating low from high seizure frequency refractory temporal lobe epilepsy (TLE).

METHODS

A consecutive series of patients with refractory temporal lobe epilepsy was studied. Based on a median baseline seizure frequency of 2.0 seizures per month, low versus high seizure frequency was defined as ≤ 2 seizures/month and > 2 seizures/month, respectively. Systemic leukocyte gene expression was analyzed for prognostic value for TLE seizure frequency. All differentially expressed genes were analyzed, with Ingenuity® Pathway Analysis (IPA®) and Reactome, to identify leukocyte gene expression and biological pathways with prognostic value for seizure frequency.

RESULTS

There were ten males and six females with a mean age of 39.4 years (range: 16 to 62 years, standard error of mean: 3.6 years). There were five patients in the high and eleven patients in the low seizure frequency cohorts, respectively. Based on a threshold of twofold change (p < 0.001, FC > 2.0, FDR < 0.05) and expression within at least two pathways from both Reactome and Ingenuity® Pathway Analysis (IPA®), 13 differentially expressed leukocyte genes were identified which were all over-expressed in the low when compared to the high seizure frequency groups, including NCF2, HMOX1, RHOB, FCGR2A, PRKCD, RAC2, TLR1, CHP1, TNFRSF1A, IFNGR1, LYN, MYD88, and CASP1. Similar analysis identified four differentially expressed genes which were all over-expressed in the high when compared to the low seizure frequency groups, including AK1, F2R, GNB5, and TYMS.

CONCLUSIONS

Low and high seizure frequency TLE are predicted by the respective upregulation and downregulation of specific leukocyte genes involved in canonical pathways of neuroinflammation, oxidative stress and lipid peroxidation, GABA (γ-aminobutyric acid) inhibition, and AMPA and NMDA receptor signaling. Furthermore, high seizure frequency-TLE is distinguished prognostically from low seizure frequency-TLE by differentially increased specific leukocyte gene expression involved in GABA inhibition and NMDA receptor signaling. High and low seizure frequency patients appear to represent two mechanistically different forms of temporal lobe epilepsy based on leukocyte gene expression.

Study of the neutrophil percentage-to-albumin ratio as a biomarker for predicting recurrence of first-episode ischemic stroke

OBJECTIVE

Neutrophils and albumin are associated with recurrence in patients with acute ischemic stroke. The purpose of this study was to evaluate the association between the neutrophil percentage-to-albumin ratio (NPAR) and recurrence in patients with first-episode acute ischemic stroke to identify a more predictive biomarker for ischemic stroke recurrence.

METHODS

In this study, the clinical data of patients with first-episode acute ischemic stroke admitted to the Department of Neurology of Shanxi Bethune Hospital from June 2021 to June 2022 were retrospectively collected, and a total of 829 patients who met the inclusion and exclusion criteria were followed up for 3 months. We evaluated the recurrence of patients within 3 months after acute ischemic stroke. Univariable and multivariable analyses were performed to determine the relationship between the NPAR and recurrence within 3 months in patients with AIS. Finally, ROC curves were used to compare the predicted values of albumin, neutrophil percentage, the neutrophil-to-lymphocyte ratio, and the NPAR.

RESULTS

A total of 829 first-episode acute ischemic stroke patients were included. The median NPAR was 1.60 (IQR 1.44-1.79). The percentage of patients with a 3-month recurrence was 6.0 % (50/829). The multivariate analysis showed that the NPAR was independently associated with the risk of recurrence within 3 months in acute ischemic stroke (OR 9.71, 95 % CI: 3.05-31.62, P < 0.001). The optimal cutoff value of the NPAR for predicting recurrence of acute ischemic stroke within 3 months was 1.78, with a sensitivity of 0.80 and a specificity of 0.75. Compared with the NLR, albumin and neutrophil percentage, the NPAR showed the greatest area under the curve (AUC) [0.78 (0.73, 0.83)]. The AUC test showed that the difference in the NPAR and neutrophil-to-lymphocyte ratio (P = 0.019), NPAR and albumin (P = 0.013), and NPAR and neutrophil percentage (P = 0.007) were statistically significant, while the difference between the other two were not statistically significant (P > 0.05).

CONCLUSION

1. The recurrence rate within 3 months among patients with a first episode of acute ischemic stroke was 6.0 %.2. The NPAR was independently associated with recurrence within 3 months among patients with a first episode of acute ischemic stroke. Moreover, the NPAR may be a more effective biomarker for predicting recurrence in acute ischemic stroke patients than the albumin level, neutrophil percentage, and neutrophil-to-lymphocyte ratio.

Predictive Role of Pre-Thrombolytic Neutrophil-Platelet Ratio on Hemorrhagic Transformation After Intravenous Thrombolysis in Acute Ischemic Stroke

To investigate the predictive role of the neutrophil-platelet ratio (NPR) before intravenous thrombolysis (IVT) on hemorrhagic transformation (HT) in patients with acute ischemic stroke (AIS). AIS patients treated with IVT without endovascular therapy between June 2019 and February 2023 were included. Patients were divided into high NPR (>35) and low NPR (≤35) groups according to the optimal threshold NPR value for identifying high-risk patients before IVT. The baseline data and the incidence of HT and symptomatic intracranial hemorrhage (sICH) were compared between the two groups. The predictive role of the NPR and other related factors on HT after IVT was analyzed by multivariate logistic regression. A total of 247 patients were included, with an average age of 67.5 ± 12.4 years. Post-thrombolytic HT was observed in 18.6% of the patients, and post-thrombolytic sICH was observed in 1.2% of the patients. There were 69 patients in the high NPR group and 178 patients in the low NPR group. The incidence of HT in the high NPR group was significantly higher than that in the low NPR group (30.4% vs 16.3%, P < .05). The incidence of sICH was significantly higher in the high NPR group than in the low NPR group (14.5% vs 1.7%, P < .001). Multivariate logistic regression analysis showed that NPR > 35 was positively correlated with HT (odds ratio (OR) = 3.236, 95% confidence interval (CI): 1.481-7.068, P = .003) and sICH (OR = 13.644, 95% CI: 2.392-77.833, P = .003). A high NPR (>35) before IVT may be a predictor of HT in AIS patients. This finding may help clinicians make clinical decisions before IVT in AIS patients.

Ocimum sanctum [Tulsi] as a Potential Immunomodulator for the Treatment of Ischemic Injury in the Brain

Stroke causes brain damage and is one of the main reasons for death. Most survivors of stroke face long-term physical disabilities and cognitive dysfunctions. In addition, they also have persistent emotional and behavioral changes. The two main treatments that are effective are reperfusion with recombinant tissue plasminogen activator and recanalization of penumbra using mechanical thrombectomy. However, these treatments are suitable only for a few patients due to limitations such as susceptibility to hemorrhage and the requirement for administering tissue plasminogen activators within the short therapeutic window during the early hours following a stroke. The paucity of interventions and treatments could be because of the multiple pathological mechanisms induced in the brain by stroke. The ongoing immune response following stroke has been attributed to the worsening brain injury. Hence, novel compounds with immunomodulatory properties that could improve the outcome of stroke patients are required. Natural compounds and medicinal herbs with anti-inflammatory activities and having minimal or no adverse systemic effect could be beneficial in treating stroke. Ocimum sanctum is a medicinal herb that can be considered an effective therapeutic option for ischemic brain injury. Ocimum sanctum, commonly known as holy basil or "Tulsi," is mentioned as the "Elixir of Life" for its healing powers. Since antiquity, Tulsi has been used in the Ayurvedic and Siddha medical systems to treat several diseases. It possesses immuno-modulatory activity, which can alter cellular and humoral immune responses. Tulsi can be considered a potential option as an immuno-modulator for treating various diseases, including brain stroke. In this review, we will focus on the immunomodulatory properties of Tulsi, specifically its effect on both innate and adaptive immunity, as well as its antioxidant and antiinflammatory properties, which could potentially be effective in treating ongoing immune reactions following ischemic brain injury.

Role of Lipocalin-2 in N1/N2 Neutrophil Polarization After Stroke

BACKGROUND

Neutrophils and Lipocalin-2 (LCN2) play pivotal roles in cerebral ischemiareperfusion (I/R) injury. However, their contribution is not fully clarified.

OBJECTIVE

This study aimed to explore the role of LCN2 and its association with neutrophil polarization in I/R injury.

METHODS

A mouse model of middle cerebral artery occlusion (MCAO) was used to induce cerebral ischemia. LCN2mAb was administered 1 h and Anti-Ly6G was administered for 3d before MCAO. The role of LCN2 in the polarity transition of neutrophils was explored using an in vitro HL-60 cell model.

RESULTS

LCN2mAb pretreatment had neuroprotective effects in mice. The expression of Ly6G was not significantly different, but the expression of N2 neutrophils was increased. In the in vitro study, LCN2mAb-treated N1-HL-60 cells induced N2-HL-60 polarization.

CONCLUSION

LCN2 may affect the prognosis of ischemic stroke by mediating neutrophil polarization.

Perspective from single-cell sequencing: Is inflammation in acute ischemic stroke beneficial or detrimental?

BACKGROUND

Acute ischemic stroke (AIS) is a common cerebrovascular event associated with high incidence, disability, and poor prognosis. Studies have shown that various cell types, including microglia, astrocytes, oligodendrocytes, neurons, and neutrophils, play complex roles in the early stages of AIS and significantly affect its prognosis. Thus, a comprehensive understanding of the mechanisms of action of these cells will be beneficial for improving stroke prognosis. With the rapid development of single-cell sequencing technology, researchers have explored the pathophysiological mechanisms underlying AIS at the single-cell level.

METHOD

We systematically summarize the latest research on single-cell sequencing in AIS.

RESULT

In this review, we summarize the phenotypes and functions of microglia, astrocytes, oligodendrocytes, neurons, neutrophils, monocytes, and lymphocytes, as well as their respective subtypes, at different time points following AIS. In particular, we focused on the crosstalk between microglia and astrocytes, oligodendrocytes, and neurons. Our findings reveal diverse and sometimes opposing roles within the same cell type, with the possibility of interconversion between different subclusters.

CONCLUSION

This review offers a pioneering exploration of the functions of various glial cells and cell subclusters after AIS, shedding light on their regulatory mechanisms that facilitate the transformation of detrimental cell subclusters towards those that are beneficial for improving the prognosis of AIS. This approach has the potential to advance the discovery of new specific targets and the development of drugs, thus representing a significant breakthrough in addressing the challenges in AIS treatment.

Recent advances in tissue repair of the blood-brain barrier after stroke

The selective permeability of the blood-brain barrier (BBB) enables the necessary exchange of substances between the brain parenchyma and circulating blood and is important for the normal functioning of the central nervous system. Ischemic stroke inflicts damage upon the BBB, triggering adverse stroke outcomes such as cerebral edema, hemorrhagic transformation, and aggravated neuroinflammation. Therefore, effective repair of the damaged BBB after stroke and neovascularization that allows for the unique selective transfer of substances from the BBB after stroke is necessary and important for the recovery of brain function. This review focuses on four important therapies that have effects of BBB tissue repair after stroke in the last seven years. Most of these new therapies show increased expression of BBB tight-junction proteins, and some show beneficial results in terms of enhanced pericyte coverage at the injured vessels. This review also briefly outlines three effective classes of approaches and their mechanisms for promoting neoangiogenesis following a stroke.

Immunothrombosis in neurovascular disease

A State of the Art lecture titled "Immunothrombosis in Neurovascular Diseases" was presented at the International Society on Thrombosis and Haemostasis Congress in 2023. Despite significant clinical advancements in stroke therapy, stroke remains a prominent contributor to both mortality and disability worldwide. Brain injury resulting from an ischemic stroke is a dynamic process that unfolds over time. Initially, an infarct core forms due to the abrupt and substantial blockage of blood flow. In the subsequent hours to days, the surrounding tissue undergoes gradual deterioration, primarily driven by sustained hypoperfusion, programmed cell death, and inflammation. While anti-inflammatory strategies have proven highly effective in experimental models of stroke, their successful translation to clinical use has proven challenging. To overcome this translational hurdle, a better understanding of the distinct immune response driving ischemic stroke brain injury is needed. In this review article, we give an overview of current knowledge regarding the immune response in ischemic stroke and the contribution of immunothrombosis to this process. We discuss therapeutic approaches to overcome detrimental immunothrombosis in ischemic stroke and how these can be extrapolated to other neurovascular diseases, such as Alzheimer's disease and multiple sclerosis. Finally, we summarize relevant new data on this topic presented during the 2023 International Society on Thrombosis and Haemostasis Congress.

Inflammation, Anti-inflammatory Interventions, and Post-stroke Cognitive Impairment: a Systematic Review and Meta-analysis of Human and Animal Studies

The pathophysiology and treatment of post-stroke cognitive impairment (PSCI) are not clear. Stroke triggers an inflammatory response, which might affect synapse function and cognitive status. We performed a systematic review and meta-analysis to assess whether patients with PSCI have increased levels of inflammatory markers and whether anti-inflammatory interventions in animals decrease PSCI. We systematically searched PubMed, EMBASE, and PsychInfo for studies on stroke. For human studies, we determined the standardized mean difference (SMD) on the association between PSCI and markers of inflammation. For animal studies, we determined the SMD of post-stroke cognitive outcome after an anti-inflammatory intervention. Interventions were grouped based on proposed mechanism of action. In patients, the SMD of inflammatory markers for those with versus those without PSCI was 0.46 (95% CI 0.18; 0.76; I2 = 92%), and the correlation coefficient between level of inflammation and cognitive scores was - 0.25 (95% CI - 0.34; - 0.16; I2 = 75%). In animals, the SMD of cognition for those treated with versus those without anti-inflammatory interventions was 1.43 (95% CI 1.12; 1.74; I2 = 83%). The largest effect sizes in treated animals were for complement inhibition (SMD = 1.94 (95% CI 1.50; 2.37), I2 = 51%) and fingolimod (SMD = 2.1 (95% CI 0.75; 3.47), I2 = 81%). Inflammation is increased in stroke survivors with cognitive impairment and is negatively correlated with cognitive functioning. Anti-inflammatory interventions seem to improve cognitive functioning in animals. Complement inhibition and fingolimod are promising therapies on reducing PSCI.

Nanomaterial-Based Drug Delivery Systems for Ischemic Stroke

Ischemic stroke is a leading cause of death and disability in the world. At present, reperfusion therapy and neuroprotective therapy, as guidelines for identifying effective and adjuvant treatment methods, are limited by treatment time windows, drug bioavailability, and side effects. Nanomaterial-based drug delivery systems have the characteristics of extending half-life, increasing bioavailability, targeting drug delivery, controllable drug release, and low toxicity, thus being used in the treatment of ischemic stroke to increase the therapeutic effects of drugs. Therefore, this review provides a comprehensive overview of nanomaterial-based drug delivery systems from nanocarriers, targeting ligands and stimulus factors of drug release, aiming to find the best combination of nanomaterial-based drug delivery systems for ischemic stroke. Finally, future research areas on nanomaterial-based drug delivery systems in ischemic stroke and the implications of the current knowledge for the development of novel treatment for ischemic stroke were identified.