Pathogenic mechanisms following ischemic stroke. Neurol Sci. 2017;38:1167-1186. [PMID: 28417216 DOI: 10.1007/s10072-017-2938-1]

Dementia after Ischemic Stroke, from Molecular Biomarkers to Therapeutic Options

Ischemic stroke is a leading cause of disability worldwide. While much of post-stroke recovery is focused on physical rehabilitation, post-stroke dementia (PSD) is also a significant contributor to poor functional outcomes. Predictive tools to identify stroke survivors at risk for the development of PSD are limited to brief screening cognitive tests. Emerging biochemical, genetic, and neuroimaging biomarkers are being investigated in an effort to unveil better indicators of PSD. Additionally, acetylcholinesterase inhibitors, NMDA receptor antagonists, dopamine receptor agonists, antidepressants, and cognitive rehabilitation are current therapeutic options for PSD. Focusing on the chronic sequelae of stroke that impair neuroplasticity highlights the need for continued investigative trials to better assess functional outcomes in treatments targeted for PSD.

Acupuncture for stroke: A bibliometric analysis of global research from 2000 to 2022

Objective

This study aimed to explore the global and future research trends in acupuncture interventions for stroke between 2000 and 2022 using bibliometric analysis.

Method

A bibliometric analysis of literature from 2000 to 2022 in the Web of Science Core Collection was conducted in this study. The analysis utilized CiteSpace, VOSviewer, and Scimago Graphica software to identify the major contributors to publications, including authors, countries, institutions, journals, references, and keywords.

Results

The bibliometric analysis yielded a total of 860 publications. There was a gradual increase in the number of publications over the study period. China published the most articles. Evidence-Based Complementary and Alternative Medicine was the journal with the greatest number of publications. The most frequently used keywords were "acupuncture," "stroke," and "electroacupuncture."

Conclusion

These analysis uncovers the research trends in acupuncture for stroke spanning 2000 to 2022 and points to prospective research frontiers. This study provides a deeper and more thorough understanding of the connotations of acupuncture for stroke and guidance and support for future research in this field.

Ginsenoside CK cooperates with bone mesenchymal stem cells to enhance angiogenesis post-stroke via GLUT1 and HIF-1α/VEGF pathway

The transplantation of bone marrow mesenchymal stem cells (MSCs) in stroke is hindered by the restricted rates of survival and differentiation. Ginsenoside compound K (CK), is reported to have a neuroprotective effect and regulate energy metabolism. We applied CK to investigate if CK could promote the survival of MSCs and differentiation into brain microvascular endothelial-like cells (BMECs), thereby alleviating stroke symptoms. Therefore, transwell and middle cerebral artery occlusion (MCAO) models were used to mimic oxygen and glucose deprivation (OGD) in vitro and in vivo, respectively. Our results demonstrated that CK had a good affinity for GLUT1, which increased the expression of GLUT1 and the production of ATP, facilitated the proliferation and migration of MSCs, and activated the HIF-1α/VEGF signaling pathway to promote MSC differentiation. Moreover, CK cooperated with MSCs to protect BMECs, promote angiogenesis and vascular density, enhance neuronal and astrocytic proliferation, thereby reducing infarct volume and consequently improving neurobehavioral outcomes. These results suggest that the synergistic effects of CK and MSCs could potentially be a promising strategy for stroke.

Unravelling the complexity of the mitochondrial Ca2+ uniporter: regulation, tissue specificity, and physiological implications

Calcium (Ca2+) signalling acts a pleiotropic message within the cell that is decoded by the mitochondria through a sophisticated ion channel known as the Mitochondrial Ca2+ Uniporter (MCU) complex. Under physiological conditions, mitochondrial Ca2+ signalling is crucial for coordinating cell activation with energy production. Conversely, in pathological scenarios, it can determine the fine balance between cell survival and death. Over the last decade, significant progress has been made in understanding the molecular bases of mitochondrial Ca2+ signalling. This began with the elucidation of the MCU channel components and extended to the elucidation of the mechanisms that regulate its activity. Additionally, increasing evidence suggests molecular mechanisms allowing tissue-specific modulation of the MCU complex, tailoring channel activity to the specific needs of different tissues or cell types. This review aims to explore the latest evidence elucidating the regulation of the MCU complex, the molecular factors controlling the tissue-specific properties of the channel, and the physiological and pathological implications of mitochondrial Ca2+ signalling in different tissues.

BONE MARROW MESENCHYMAL STROMAL CELL-DERIVED EXOSOMAL NRF2 AMELIORATES CEREBRAL ISCHEMIA-REPERFUSION INJURY BY TRANSCRIPTIONALLY ACTIVATING LIN28A

ABSTRACT

Background: Cerebral ischemia-reperfusion (I/R) injury (CIRI) have severe consequences on brain function, and the exciting evidence has revealed protective role of acyl-CoA synthetase long chain family member 4 (Lin28a) against cerebral ischemia-reperfusion injury. The present work aims to reveal its molecular mechanism in regulating CIRI, with the hope of providing a therapeutic method for cerebral I/R injury. We hypothesized that the exosomal nuclear factor erythroid 2-related factor 2 (NRF2) derived from bone marrow mesenchymal stromal cells could transcriptionally activate Lin28a and thereby alleviate cerebral ischemia-reperfusion injury. This hypothesis was validated in the present work. Methods: Middle cerebral artery occlusion (MCAO) model was established using C57BL/6J mice, and the neurological deficit, infarct volume, and brain water content were assessed to evaluate neuron injury. Human glioblastoma cells (A172) were subjected to oxygen-glucose deprivation and reoxygenation (OGD/R) treatment to mimic a cerebral I/R injury cell model. Exosome isolation reagent was used to isolate exosomes from cell supernatant of bone marrow mesenchymal stromal cells through sequential centrifugation and filtration steps. mRNA expression level of Lin28a was detected by quantitative real-time polymerase chain reaction. Protein expression was analyzed by western blotting assay. TUNEL cell apoptosis detection kit was used to analyze cell apoptosis in brain tissues. Enzyme-linked immunosorbent assays and commercial kits were used to detect levels of inflammatory markers and oxidative stress markers. Ferrous Iron Colorimetric Assay Kit and Fe 2+ colorimetric assay kit were used to analyze Fe 2+ level. The association of Lin28a and NRF2 was identified by chromatin immunoprecipitation assay and dual-luciferase reporter assay. Results: The treatment of MCAO substantially augmented infarct volume in mice, impaired neurological function, and elevated brain water content. Lin28a was lowly expressed in brain tissues of mice with CIRI, and its overexpression protected against cerebral I/R injury of MCAO mice. Moreover, Lin28a overexpression protected A172 cells against OGD/R treatment-induced injury. Additionally, NRF2 transcriptionally activated Lin28a in A172 cells. Bone marrow mesenchymal stromal cell-derived exosomes increased Lin28a expression in a NRF2-dependent manner. Bone marrow mesenchymal stromal cell-derived exosomal NRF2 improved OGD/R-induced A172 cell injury by inducing Lin28a production. Conclusion: Bone marrow mesenchymal stromal cell-derived exosomal NRF2 improved CIRI by transcriptionally activating Lin28a.

Metabolomic discoveries for early diagnosis and traditional Chinese medicine efficacy in ischemic stroke

Ischemic stroke (IS), a devastating cerebrovascular accident, presents with high mortality and morbidity. Following IS onset, a cascade of pathological changes, including excitotoxicity, inflammatory damage, and blood-brain barrier disruption, significantly impacts prognosis. However, current clinical practices struggle with early diagnosis and identifying these alterations. Metabolomics, a powerful tool in systems biology, offers a promising avenue for uncovering early diagnostic biomarkers for IS. By analyzing dynamic metabolic profiles, metabolomics can not only aid in identifying early IS biomarkers but also evaluate Traditional Chinese Medicine (TCM) efficacy and explore its mechanisms of action in IS treatment. Animal studies demonstrate that TCM interventions modulate specific metabolite levels, potentially reflecting their therapeutic effects. Identifying relevant metabolites in cerebral ischemia patients holds immense potential for early diagnosis and improved outcomes. This review focuses on recent metabolomic discoveries of potential early diagnostic biomarkers for IS. We explore variations in metabolites observed across different ages, genders, disease severity, and stages. Additionally, the review examines how specific TCM extracts influence IS development through metabolic changes, potentially revealing their mechanisms of action. Finally, we emphasize the importance of integrating metabolomics with other omics approaches for a comprehensive understanding of IS pathophysiology and TCM efficacy, paving the way for precision medicine in IS management.

Effects of peripheral blood cells on ischemic stroke: Greater immune response or systemic inflammation?

Ischemic stroke is still one of the most serious medical conditions endangering human health worldwide. Current research on the mechanism of ischemic stroke focuses on the primary etiology as well as the subsequent inflammatory response and immune modulation. Recent research has revealed that peripheral blood cells and their components are crucial to the ensuing progression of ischemic stroke. However, it remains unclear whether blood cell elements are principally in charge of systemic inflammation or immunological regulation, or if their participation is beneficial or harmful to the development of ischemic stroke. In this review, we aim to describe the changes in peripheral blood cells and their corresponding parameters in ischemic stroke. Specifically, we elaborate on the role of each peripheral component in the inflammatory response or immunological modulation as well as their interactions. It has been suggested that more specific therapies aimed at targeting peripheral blood cell components and their role in inflammation or immunity are more favorable to the treatment of ischemic stroke.

Icariin inhibits apoptosis in OGD-induced neurons by regulating M2 pyruvate kinase

Background

Ischaemic stroke can lead to many complications, but treatment options are limited. Icariin is a traditional Chinese medicine with reported neuroprotective effects against ischaemic cerebral injury; however, the underlying mechanisms by which icariin ameliorates cell apoptosis require further study.

Purpose

This study aimed to investigate the therapeutic potential of icariin after ischaemic stroke and the underlying molecular mechanisms.

Methods

N2a neuronal cells were used to create an in vitro oxygen-glucose deprivation (OGD) model. The effects of icariin on OGD cells were assessed using the CCK-8 kit to detect the survival of cells and based on the concentration, apoptosis markers, inflammation markers, and M2 pyruvate kinase isoenzyme (PKM2) expression were detected using western blotting, RT-qPCR, and flow cytometry. To investigate the underlying molecular mechanisms, we used the PKM2 agonist TEPP-46 and detected apoptosis-related proteins.

Results

We demonstrated that icariin alleviated OGD-induced apoptosis in vitro. The expression levels of the apoptosis marker proteins caspase-3 and Bax were upregulated and Bcl-2 was downregulated. Furthermore, icariin reduced inflammation and downregulated the expression of PKM2. Moreover, activation of the PKM2 by pretreatment with the PKM2 agonist TEPP-46 enhanced the effects on OGD induced cell apoptosis in vitro.

Conclusion

This study elucidated the underlying mechanism of PKM2 in OGD-induced cell apoptosis and highlighted the potential of icariin in the treatment of ischaemic stroke.

Geraniol attenuates oxygen-glucose deprivation/reoxygenation-induced ROS-dependent apoptosis and permeability of human brain microvascular endothelial cells by activating the Nrf-2/HO-1 pathway

Blood-brain barrier breakdown and ROS overproduction are important events during the progression of ischemic stroke aggravating brain damage. Geraniol, a natural monoterpenoid, possesses anti-apoptotic, cytoprotective, anti-oxidant, and anti-inflammatory activities. Our study aimed to investigate the effect and underlying mechanisms of geraniol in oxygen-glucose deprivation/reoxygenation (OGD/R)-induced human brain microvascular endothelial cells (HBMECs). Apoptosis, caspase-3 activity, and cytotoxicity of HBMECs were evaluated using TUNEL, caspase-3 activity, and CCK-8 assays, respectively. The permeability of HBMECs was examined using FITC-dextran assay. Reactive oxygen species (ROS) production was measured using the fluorescent probe DCFH-DA. The protein levels of zonula occludens-1 (ZO-1), occludin, claudin-5, β-catenin, nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) were determined by western blotting. Geraniol showed no cytotoxicity in HBMECs. Geraniol and ROS scavenger N-acetylcysteine (NAC) both attenuated OGD/R-induced apoptosis and increase of caspase-3 activity and the permeability to FITC-dextran in HBMECs. Geraniol relieved OGD/R-induced ROS accumulation and decrease of expression of ZO-1, occludin, claudin-5, and β-catenin in HBMECs. Furthermore, we found that geraniol activated Nrf2/HO-1 pathway to inhibit ROS in HBMECs. In conclusion, geraniol attenuated OGD/R-induced ROS-dependent apoptosis and permeability in HBMECs through activating the Nrf2/HO-1 pathway.

Targeting pyroptosis to treat ischemic stroke: From molecular pathways to treatment strategy

Ischemic stroke is the primary reason for human disability and death, but the available treatment options are limited. Hence, it is imperative to explore novel and efficient therapies. In recent years, pyroptosis (a pro-inflammatory cell death characterized by inflammation) has emerged as an important pathological mechanism in ischemic stroke that can cause cell death through plasma membrane rupture and release of inflammatory cytokines. Pyroptosis is closely associated with inflammation, which exacerbates the inflammatory response in ischemic stroke. The level of inflammasomes, GSDMD, Caspases, and inflammatory factors is increased after ischemic stroke, exacerbating brain injury by mediating pyroptosis. Hence, inhibition of pyroptosis can be a therapeutic strategy for ischemic stroke. In this review, we have summarized the relationship between pyroptosis and ischemic stroke, as well as a series of treatments to attenuate pyroptosis, intending to provide insights for new therapeutic targets on ischemic stroke.

Sophoricoside ameliorates cerebral ischemia-reperfusion injury dependent on activating AMPK

AIMS

Ischemic stroke accounts for 87% of all strokes, and its death and disability bring a huge burden to society. Brain injury caused by ischemia-reperfusion (I/R) is also a major difficulty in clinical treatment and prognosis. Sophoricoside (SOP) is an isoflavone glycoside isolated from the seed of medical herb Sophora japonica L. Previously, SOP was found to be effective in anti-inflammation and glucose-lipid metabolism-related diseases. In order to investigate whether SOP has a regulatory effect on cerebral I/R injury, we conducted this study.

METHODS

Here, by application of SOP into MCAO (transient middle cerebral artery occlusion)-induced mice and OGD/R (oxygen glucose deprivation/reperfusion)-induced primary neurons, the regulation effects of SOP was analyzed by detecting neurological score of post-stroke mice, phenotypes of brains and brain sections, cell viabilities, and apoptosis- and inflammation-regulation. RNA sequencing and molecular biology experiments were performed to explore the mechanism of SOP regulating cerebral I/R injury.

RESULTS

SOP administration decreased the infarct size, neurological deficit score, neuronal cell injury, inflammation and apoptosis. Mechanistically, SOP exerted its protective effect by activating the AMP-activated protein kinase (AMPK) signaling pathway.

CONCLUSION

SOP inhibits cerebral I/R injury by promoting the phosphorylation of AMPK.

Comprehensive analysis of lncRNA-miRNA-mRNA ceRNA network in ischemic stroke

Objective

Competitive endogenous RNA (ceRNA) networks have uncovered a novel mode of RNA interaction, and are implicated in various biological processes and the pathogenesis of IS. This study aimed to explore the potential mechanisms underlying the ceRNA network in IS.

Methods

Four public datasets containing lncRNA and mRNA (GSE22255 and GSE16561) and miRNA (GSE55937 and GSE43618) expression profiles from the GEO database were systematically analyzed to explore the role of RNAs in ischemic stroke (IS). Differentially expressed mRNAs (DEmRNAs), lncRNAs (DElncRNAs), and miRNAs (DEmiRNAs) between IS and normal control samples were identified. LncRNA-miRNA and miRNA-mRNA interactions were predicted, and the competing endogenous RNA (ceRNA) regulatory network was constructed using the Cytoscape software. The correlation between the RNAs in the ceRNA network and the clinical features of the samples was evaluated. Finally, principal component analysis was performed on the RNAs that constitute the ceRNA regulatory network, and their differential expression and principal component relationships among different types of samples were observed.

Results

A total of 224 DEmRNAs, 7 DEmiRNAs, and four DElncRNAs related to IS in four datasets were identified. Then, through target gene prediction, a lncRNA-miRNA-mRNA ceRNA network that contained 3 DElncRNAs, 2 DEmiRNAs, and 24 DEmRNAs was constructed. Correlations of the clinical characteristics showed that PART1 and SERPINH1 were related to clinical diseases, WNK1 was related to lifestyle, and seven RNAs were related to age. PCA results indicate that three principal components of PC1, PC2, and PC3 can clearly distinguish between control and IS samples.

Conclusion

Overall, we constructed a ceRNA network in IS, which could offer insights into the molecular mechanism and potential prognostic biomarkers for further research.

Polydopamine-modified black phosphorus nanosheet drug delivery system for the treatment of ischemic stroke

Black phosphorus (BP), as a representative metal-free semiconductor, has been extensively explored. It has a higher drug loading capacity in comparison to conventional materials and also possesses excellent biocompatibility and biodegradability. Furthermore, BP nanosheets can enhance the permeability of the blood-brain barrier (BBB) upon near-infrared (NIR) irradiation, owing to their photothermal effect. However, the inherent instability of BP poses a significant limitation, highlighting the importance of surface modification to enhance its stability. Ischemic stroke (IS) is caused by the occlusion of blood vessels, and its treatment is challenging due to the hindrance caused by the BBB. Therefore, there is an urgent need to identify improved methods for bypassing the BBB for more efficient IS treatment. This research devised a novel drug delivery approach based on pterostilbene (Pte) supported by BP nanosheets, modified with polydopamine (PDA) to form BP-Pte@PDA. This system shows robust stability and traverses the BBB using effective photothermal mechanisms. This enables the release of Pte upon pH and NIR stimuli, offering potential therapeutic advantages for treating IS. In a middle cerebral artery occlusion mouse model, the BP-Pte@PDA delivery system significantly reduced infarct size, and brain water content, improved neurological deficits, reduced the TLR4 inflammatory factor expression, and inhibited cell apoptosis. In summary, the drug delivery system fabricated in this study thus demonstrated good stability, therapeutic efficacy, and biocompatibility, rendering it suitable for clinical application.

Circ_0000115 Protects Against Cerebral Ischemia Injury by Suppressing Neuronal Apoptosis, Oxidative Stress and Inflammation by miR-1224-5p/Nos3 Axis In Vitro

Cerebral ischemia is a severe neurological disability related to neuronal apoptosis and cellular stress response. Circular RNAs (circRNAs) are emerging regulators of cerebral ischemia. Herein, this study proposed to probe the action of circ_0000115 in cerebral ischemia injury. The mouse neuroblastoma cells N2a and HT22 underwent oxygen-glucose deprivation (OGD) were used as a model of in vitro cerebral ischemia. Levels of genes and proteins were detected by qRT-PCR and western blotting. Cell proliferation and apoptosis were determined by EdU assay and flow cytometry. Western blotting was used to detect the protein level of pro-inflammatory factors. The oxidative stress injury was evaluated by detecting reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) generation. Dual-luciferase reporter and RIP assays were used to confirm the target relationship between miR-1224-5p and circ_0000115 or nitric oxide synthase 3 (NOS3). OGD exposure decreased circ_0000115 and NOS3 expression, and increased miR-1224-5p in N2a and HT22 cells in a time-dependent manner. Circ_0000115 silencing attenuated OGD-induced apoptosis, oxidative stress and inflammation in N2a and HT22 cells. Mechanistically, circ_0000115 directly sponged miR-1224-5p, which targeted NOS3. Furthermore, rescue experiments showed that miR-1224-5p overexpression abolished the neuroprotective effect of circ_0000115 in N2a and HT22 cells under OGD treatment. Besides that, silencing of miR-1224-5p protected N2a and HT22 cells against OGD-evoked injury, which was counteracted by NOS3 knockdown. Circ_0000115 protects N2a and HT22 cells against OGD-evoked neuronal apoptosis, inflammation, and oxidative stress via the miR-1224-5p/NOS3 axis, providing an exciting view of the pathogenesis of cerebral ischemia.

Velvet antler polypeptide (VAP) protects against cerebral ischemic injury through NF-κB signaling pathway in vitro

OBJECTIVE

Velvet antler polypeptide (VAP) has been shown to play important roles in the immune and nervous systems. The purpose of this study was to investigate the protective effects of VAP on cerebral ischemic injury with the involvement of NF-κB signaling pathway in vitro.

MATERIALS AND METHODS

PC-12 cells stimulated by oxygen-glucose deprivation/reperfusion (OGD/R) was used to mimic cerebral ischemic injury in vitro. The levels of ROS, SOD, and intracellular concentrations of Ca2+ were measured by the relevant kits. Meanwhile, the expressions of inflammatory cytokines (IL-6, IL-1β, and TNF-α) were determined by ELISA kit assay. In addition, MTT, EdU, and flow cytometry assays were used to measure the cell proliferation and apoptosis. Besides which, the related proteins of NF-κB signaling pathway were measured by western blotting assay.

RESULTS

VAP alleviated cerebral ischemic injury by reducing OGD/R-induced oxidative stress, inflammation, and apoptosis in PC-12 cells in a time dependent manner. Mechanistically, VAP inhibited the levels of p-p65 and p-IkB-α in a time dependent manner, which was induced by OGD/R operation. Moreover, NF-κB agonist diprovocim overturned the suppression effects of VAP on OGD/R-induced oxidative stress, inflammation, and apoptosis in PC-12 cells.

CONCLUSIONS

The results demonstrate that VAP may alleviate cerebral ischemic injury by suppressing the activation of NF-κB signaling pathway.

Association between serum calcium and prognosis in patients with acute ischemic stroke in ICU: analysis of the MIMIC-IV database

BACKGROUND

While serum Ca has proven to be a reliable predictor of mortality across various diseases, its connection with the clinical outcomes of ischemic stroke (IS) remains inconclusive. Our research aimed to explore the relationships between serum total Ca (tCa) and serum ionized Ca (iCa) and mortality among acute IS (AIS) patients.

METHODS

We gathered data from 1773 AIS patients in the Medical Information Mart for Intensive Care Database IV, including baseline demographic data, comorbidities, vital signs, laboratory-based data, and scoring systems. Endpoints for the study encompassed 30-d, 90-d, and 365-d all-cause mortalities. Employing restricted cubic spline Cox regression, we explored potential nonlinear relationships between admission serum iCa and tCa levels and mortality. Participants were categorized into four groups based on serum iCa and tCa quartiles. Multivariable Cox regression analysis was then conducted to evaluate the independent association of iCa and tCa quartiles with all-cause mortality.

RESULTS

The restricted cubic spline revealed a U-shaped association between iCa and 30-d and 90-d mortality (P<0.05), while the relationship between iCa and 365-d mortality was linear (P<0.05). After adjusting for confounders, multivariable Cox analysis demonstrated that the lowest serum iCa level quartile was independently associated with increased risks of 30-d, 90-d, and 365-d mortality. Similarly, the highest serum iCa level quartile was independently associated with increased risks of 30-d and 90-d mortality, but not 365-d mortality. Notably, serum tCa level showed no association with increased risks of 30-d, 90-d, and 365-d mortality.

CONCLUSIONS

Our findings suggest that serum iCa, rather than tCa, is linked to ischemic stroke prognosis. Both high and low serum iCa levels are associated with poor short-term prognosis, while only low serum iCa is associated with poor long-term prognosis in AIS patients.

Perivascular macrophages in cerebrovascular diseases

Cerebrovascular diseases are a major cause of stroke and dementia, both requiring long-term care. These diseases involve multiple pathophysiologies, with mitochondrial dysfunction being a crucial contributor to the initiation of inflammation, apoptosis, and oxidative stress, resulting in injuries to neurovascular units that include neuronal cell death, endothelial cell death, glial activation, and blood-brain barrier disruption. To maintain brain homeostasis against these pathogenic conditions, brain immune cells, including border-associated macrophages and microglia, play significant roles as brain innate immunity cells in the pathophysiology of cerebrovascular injury. Although microglia have long been recognized as significant contributors to neuroinflammation, attention has recently shifted to border-associated macrophages, such as perivascular macrophages (PVMs), which have been studied based on their crucial roles in the brain. These cells are strategically positioned around the walls of brain vessels, where they mainly perform critical functions, such as perivascular drainage, cerebrovascular flexibility, phagocytic activity, antigen presentation, activation of inflammatory responses, and preservation of blood-brain barrier integrity. Although PVMs act as scavenger and surveillant cells under normal conditions, these cells exert harmful effects under pathological conditions. PVMs detect mitochondrial dysfunction in injured cells and implement pathological changes to regulate brain homeostasis. Therefore, PVMs are promising as they play a significant role in mitochondrial dysfunction and, in turn, disrupt the homeostatic condition. Herein, we summarize the significant roles of PVMs in cerebrovascular diseases, especially ischemic and hemorrhagic stroke and dementia, mainly in correlation with inflammation. A better understanding of the biology and pathobiology of PVMs may lead to new insights on and therapeutic strategies for cerebrovascular diseases.

Exosomes derived from human umbilical cord mesenchymal stem cells pretreated by monosialoteterahexosyl ganglioside alleviate intracerebral hemorrhage by down-regulating autophagy

PURPOSE

Intracerebral hemorrhage (ICH) results in substantial morbidity, mortality, and disability. Depleting neural cells in advanced stages of ICH poses a significant challenge to recovery. The objective of our research is to investigate the potential advantages and underlying mechanism of exosomes obtained from human umbilical cord mesenchymal stem cells (hUMSCs) pretreated with monosialoteterahexosyl ganglioside (GM1) in the prevention of secondary brain injury (SBI) resulting from ICH.

PATIENTS AND METHODS

In vitro, hUMSCs were cultured and induced to differentiate into neuron-like cells after they were pretreated with 150 μg/mL GM1. The exosomes extracted from the culture medium following a 6-h pretreatment with 150 μg/mL GM1 were used as the treatment group. Striatal infusion of collagenase and hemoglobin (Hemin) was used to establish in vivo and in vitro models of ICH.

RESULTS

After being exposed to 150 μg/mL GM1 for 6 h, specific cells displayed typical neuron-like cell morphology and expressed neuron-specific enolase (NSE). The rate of differentiation into neuron-like cells was up to (15.9 ± 5.8) %, and the synthesis of N-Acetylgalactosaminyltransferase (GalNAcT), which is upstream of GM1, was detected by Western blot. This study presented an increase in the synthesis of GalNAcT. Compared with the ICH group, apoptosis in the treatment group was remarkably reduced, as detected by TUNEL, and mitochondrial membrane potential was restored by JC-1. Additionally, Western blot revealed the restoration of up-regulated autophagy markers Beclin-1 and LC3 and the down-regulation of autophagy marker p62 after ICH.

CONCLUSION

These findings suggest that GM1 is an effective agent to induce the differentiation of hUMSCs into neuron-like cells. GM1 can potentially increase GalNAcT production through "positive feedback", which generates more GM1 and promotes the differentiation of hUMSCs. After pretreatment with GM1, exosomes derived from hUMSCs (hUMSCs-Exos) demonstrate a neuroprotective effect by inhibiting autophagy in the ICH model. This study reveals the potential mechanism by which GM1 induces differentiation of hUMSCs into neuron-like cells and confirms the therapeutic effect of hUMSCs-Exos pretreated by GM1 (GM1-Exos) on an ICH model, potentially offering a new direction for stem cell therapy in ICH.

4-Hydroxysesamin, a Modified Natural Compound, Attenuates Neuronal Apoptosis After Ischemic Stroke via Inhibiting MAPK Pathway

Background

The 4-hydroxysesamin (4-HS, a di-tetrahydrofuran lignin) is a modified sesamin that was prepared in the laboratory. This preclinical study was designed to preliminarily investigate the neuroprotective properties of 4-HS.

Methods

In vitro, neuronal injury and inflammation were simulated by oxygen-glucose deprivation and lipopolysaccharide (LPS) exposure in mouse hippocampal neuronal HT22 cell line, and treated with 4-HS and/or metformin (MET, MAPK pathway activator for exploring mechanism). CCK-8, flow cytometry, and enzyme-linked immunosorbent assay were performed to evaluate cell viability, apoptosis, and inflammation. Apoptosis- and pathway-related proteins were detected by Western blotting. Middle cerebral artery occlusion (MCAO) was constructed as a stroke model and treated with 4-HS for in vivo confirmation. Histological staining was used for in vivo evaluation of 4-HS properties.

Results

The 4-HS showed similar anti-inflammatory activity to sesamin but did not affect the cell viability of HT22 cells. In vitro, 4-HS improved the cell viability, ameliorated neuronal apoptosis, along with the reversion of apoptotic proteins (Bax, cleaved-caspase 3/9, Bcl-2) expression and inflammatory cytokines (IL-6, TNF-α, IL-10) in LPS-treated HT22 cells. The 4-HS suppressed the phosphorylation of ERK, JNK, and p38 but the addition of MET reversed 4-HS-induced changes of phenotype and protein expression in LPS-treated cells. In vivo, 4-HS showed apparent improvement in cerebral infarction, brain tissue morphology, neuronal architecture, apoptosis, and inflammation of MCAO mice, and also showed inhibiting effects on the phosphorylation of ERK, JNK, and p38, confirming in vivo results.

Conclusion

In this first pre-clinical study on 4-HS, we preliminarily demonstrated the neuroprotective properties of 4-HS both in cell and animal models, and proposed that the underlying mechanism might be associated with the MAPK pathway.

Histone deacetylase inhibition by suberoylanilide hydroxamic acid during reperfusion promotes multifaceted brain and vascular protection in spontaneously hypertensive rats with transient ischaemic stroke

Hypertension is the most prevalent modifiable risk factor for stroke and is associated with worse functional outcomes. Pharmacological inhibition of histone deacetylases by suberoylanilide hydroxamic acid (SAHA) modulates gene expression and has emerged as a promising therapeutic approach to reduce ischaemic brain injury. Here, we have tested the therapeutic potential of SAHA administered during reperfusion in adult male spontaneously hypertensive (SHR) rats subjected to transient middle cerebral artery occlusion (tMCAO; 90 min occlusion/24 h reperfusion). Animals received a single dose of SAHA (50 mg/kg) or vehicle i.p. at 1, 4, or 6 h after reperfusion onset. The time-course of brain histone H3 acetylation was studied. After tMCAO, drug brain penetrance and beneficial effects on behavioural outcomes, infarct volume, oedema, angiogenesis, blood-brain barrier integrity, cerebral artery oxidative stress and remodelling, and brain and vascular inflammation were evaluated. SAHA increased brain histone H3 acetylation from 1 to 6 h after injection, reaching the ischaemic brain administered during reperfusion. Treatment given at 4 h after reperfusion onset improved neurological score, reduced infarct volume and oedema, attenuated microglial activation, prevented exacerbated MCA angiogenic sprouting and blood-brain barrier breakdown, normalised MCA oxidative stress and remodelling, and modulated brain and cerebrovascular cytokine expression. Overall, we demonstrate that SAHA administered during early reperfusion exerts robust brain and vascular protection after tMCAO in hypertensive rats. These findings are aligned with previous research in ischaemic normotensive mice and help pave the way to optimise the design of clinical trials assessing the effectiveness and safety of SAHA in ischaemic stroke.

Chinese herbal medicine Ginkgo biloba L. preparations for ischemic stroke: An overview of systematic reviews and meta-analyses

BACKGROUND

Ginkgo biloba L. preparations (GBLPs) are a class of Chinese herbal medicine used in the adjuvant treatment of ischemic stroke (IS). Recently, several systematic reviews (SRs) and meta-analyses (MAs) of GBLPs for IS have been published.

OBJECTIVE

This overview aims to assess the quality of related SRs and MAs.

SEARCH STRATEGY

PubMed, Embase, Cochrane Library, Web of Science, Chinese Biological Medicine, China National Knowledge Infrastructure, Wanfang, and Chinese Science and Technology Journals databases were searched from their inception to December 31, 2022.

INCLUSION CRITERIA

SRs and MAs of randomized controlled trials (RCTs) that explored the efficacy of GBLPs for patients with IS were included.

DATA EXTRACTION AND ANALYSIS

Two independent reviewers extracted data and assessed the methodological quality, risk of bias (ROB), reporting quality, and credibility of evidence of the included SRs and MAs using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2), Risk of Bias in Systematic Reviews (ROBIS), the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA), and the Grading of Recommendations Assessment, Development and Evaluation (GRADE), respectively. Additionally, descriptive analysis and data synthesis were conducted.

RESULTS

Twenty-nine SRs/MAs involving 119 outcomes were included in this review. The overall methodological quality of all SRs/MAs was critically low based on AMSTAR 2, and 28 had a high ROB based on the ROBIS. According to the PRISMA statement, the reporting items of the included SRs/MAs are relatively complete. The results based on GRADE showed that of the 119 outcomes, 8 were rated as moderate quality, 24 as low quality, and 87 as very low quality. Based on the data synthesis, GBLPs used in conjunction with conventional treatment were superior to conventional treatment alone for decreasing neurological function scores.

CONCLUSION

GBLPs can be considered a beneficial supplemental therapy for IS. However, because of the low quality of the existing evidence, high-quality RCTs and SRs/MAs are warranted to further evaluate the benefits of GBLPs for treating IS. Please cite this article as: Meng TT, You YP, Li M, Guo JB, Song XB, Ding JY, Xie XL, Li AQ, Li SJ, Yin XJ, Wang P, Wang Z, Wang BL, He QY. Chinese herbal medicine Ginkgo biloba L. preparations for ischemic stroke: An overview of systematic reviews and meta-analyses. J Integr Med. 2024;22(2): 163-179.

Research hotspots and frontiers of preconditioning in cerebral ischemia: A bibliometric analysis

Background

Preconditioning is a promising strategy against ischemic brain injury, and numerous studies in vitro and in vivo have demonstrated its neuroprotective effects. However, at present there is no bibliometric analysis of preconditioning in cerebral ischemia. Therefore, a comprehensive overview of the current status, hot spots, and emerging trends in this research field is necessary.

Materials and methods

Studies on preconditioning in cerebral ischemia from January 1999-December 2022 were retrieved from the Web of Science Core Collection (WOSCC) database. CiteSpace was used for data mining and visual analysis.

Results

A total of 1738 papers on preconditioning in cerebral ischemia were included in the study. The annual publications showed an upwards and then downwards trend but currently remain high in terms of annual publications. The US was the leading country, followed by China, the most active country in recent years. Capital Medical University published the largest number of articles. Perez-Pinzon, Miguel A contributed the most publications, while KITAGAWA K was the most cited author. The focus of the study covered three areas: (1) relevant diseases and experimental models, (2) types of preconditioning and stimuli, and (3) mechanisms of ischemic tolerance. Remote ischemic preconditioning, preconditioning of mesenchymal stem cells (MSCs), and inflammation are the frontiers of research in this field.

Conclusion

Our study provides a visual and scientific overview of research on preconditioning in cerebral ischemia, providing valuable information and new directions for researchers.

Therapeutic potentialities of green tea (Camellia sinensis) in ischemic stroke: biochemical and molecular evidence

Ischemic stroke is a leading cause of disability and death in patients. Despite considerable recent advances in the treatment of ischemic stroke, only a limited number of effective neuroprotective agents are available for stroke. Green tea (Camellia sinensis) is a popular herbal plant, and numerous studies have indicated its health benefits for several diseases. Green tea is of interest due to its high content of catechin derivatives, including epicatechin, gallocatechin, epicatechin gallate, epigallocatechin, and epigallocatechin-3-gallate. This review tried to develop a feasible background for the potential effects of green tea and its bioactive derivatives concerning protection against ischemic stroke. Green tea's antioxidants, anti-inflammatory, anti-apoptotic, and neuroprotective effects are believed to be efficacious in stroke treatment. Evidence supports the idea that green tea can be used to assist in treating ischemic stroke.

Frequency specific alterations of the degree centrality in patients with acute basal ganglia ischemic stroke: a resting-state fMRI study

This study intended to investigate the frequency specific brain oscillation activity in patients with acute basal ganglia ischemic stroke (BGIS) by using the degree centrality (DC) method. A total of 34 acute BGIS patients and 44 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rs-fMRI) scanning. The DC values in three frequency bands (conventional band: 0.01-0.08 Hz, slow‑4 band: 0.027-0.073 Hz, slow‑5 band: 0.01-0.027 Hz) were calculated. A two-sample t-test was used to explore the between-group differences in the conventional frequency band. A two-way repeated-measures analysis of variance (ANOVA) was used to analyze the DC differences between groups (BGIS patients, HCs) and bands (slow‑4, slow‑5). Moreover, correlations between DC values and clinical indicators were performed. In conventional band, the DC value in the right middle temporal gyrus was decreased in BGIS patients compared with HCs. Significant differences of DC were observed between the two bands mainly in the bilateral cortical brain regions. Compared with the HCs, the BGIS patients showed increased DC in the right superior temporal gyrus and the left precuneus, but decreased mainly in the right inferior temporal gyrus, right inferior occipital gyrus, right precentral, and right supplementary motor area. Furthermore, the decreased DC in the right rolandic operculum in slow-4 band and the right superior temporal gyrus in slow-5 band were found by post hoc two-sample t-test of main effect of group. There was no significant correlation between DC values and clinical scales after Bonferroni correction. Our findings showed that the DC changes in BGIS patients were frequency specific. Functional abnormalities in local brain regions may help us to understand the underlying pathogenesis mechanism of brain functional reorganization of BGIS patients.

Electroacupuncture at GB20 improves cognitive ability and synaptic plasticity via the CaM-CaMKII-CREB signaling pathway following cerebral ischemia-reperfusion injury in rats

BACKGROUND

This study aimed to investigate the effects of electroacupuncture (EA) on cognitive recovery and synaptic remodeling in a rat model of middle cerebral artery occlusion (MCAO) followed by reperfusion and explore the possible mechanism.

METHOD

Focal cerebral ischemia was modeled in healthy adult Sprague-Dawley rats by MCAO. The MCAO rats were classified into four groups: sham, MCAO, MCAO + GB20 (receiving EA at GB20) and MCAO + NA (receiving EA at a "non-acupoint" location not corresponding to any traditional acupuncture point location about 10 mm above the iliac crest). Neurological deficit scores and behavior were assessed before and during the treatment. After intervention for 7 days, the hippocampus was dissected to analyze growth-associated protein (GAP)-43, synaptophysin (SYN) and postsynaptic density protein (PSD)-95 expression levels by Western blotting. Bioinformatic analysis and primary hippocampal neurons with calcium-voltage gated channel subunit alpha 1B (CACNA1B) gene overexpression were used to screen the target genes for EA against MCAO.

RESULTS

Significant amelioration of neurological deficits and learning/memory were found in MCAO + GB20 rats compared with MCAO or MCAO + NA rats. Protein levels of GAP-43, SYN and PSD-95 were significantly improved in MCAO + GB20-treated rats together with an increase in the number of synapses in the hippocampal CA1 region. CACNA1B appeared to be a target gene of EA in MCAO. There were increased mRNA levels of CACNA1B, calmodulin (CaM), Ca2+/calmodulin-dependent protein kinase type II (CaMKII) and cyclic adenosine monophosphate response element binding (CREB) and increased phosphorylation of CaM, CaMKII and CREB in the hippocampal region in MCAO + GB20 versus MCAO and MCAO + NA groups. CACNA1B overexpression modulated expression of the CaM-CaMKII-CREB axis.

CONCLUSION

EA treatment at GB20 may ameliorate the negative effects of MCAO on cognitive function in rats by enhancing synaptic plasticity. EA treatment at GB20 may exert this neuroprotective effect by regulating the CACNA1B-CaM-CaMKII-CREB axis.

The efficacy and safety of interleukin-1 receptor antagonist in stroke patients: A systematic review

Stroke is the leading cause of disability worldwide, yet there is currently no effective treatment available to mitigate its negative consequences. Pro-inflammatory cytokines, such as interleukin-1 (IL-1), are known to play a crucial role in exacerbating the aftermath of stroke. Thus, it is hypothesized that blocking inflammation and administering anti-inflammatory drugs at an optimal time and dosage may improve the long-term quality of life for stroke patients. This systematic review examines the effectiveness and safety of IL-1 receptor antagonist (IL-1Ra), commercially known as "anakinra," in clinical studies involving the treatment of stroke patients. A comprehensive literature search was conducted until October 2023 to identify relevant studies. The search yielded 1403 articles, out of which 598 were removed due to duplication. After a thorough review of 805 titles and abstracts, 797 articles were further excluded, resulting in 8 studies being included in this systematic review. The findings from all the included studies demonstrate that IL-1Ra is safe for use in acute ischemic and hemorrhagic stroke patients, with no significant adverse events reported. Additionally, biomarkers, clinical assessments, serious adverse events (AEs), and non-serious AEs consistently showed more favorable outcomes in IL-1Ra receiving patients. Stroke elevates the levels of several inflammatory cytokines, however, administration of IL-1RA directly or indirectly modulates these markers and improves some clinical outcomes, suggesting a potential therapeutic benefit of this intervention.

Alleviated cerebral infarction in male mice lacking all nitric oxide synthase isoforms after middle cerebral artery occlusion

PURPOSE

The role of the nitric oxide synthases (NOSs) system in cerebral infarction has been examined in pharmacological studies with non-selective NOSs inhibitors. However, due to the non-specificity of the non-selective NOSs inhibitors, its role remains to be fully elucidated. We addressed this issue in mice in which neuronal, inducible, and endothelial NOS isoforms were completely disrupted.

METHODS AND RESULTS

We newly generated mice lacking all three NOSs by crossbreeding each single NOS-/- mouse. In the male, cerebral infarct size at 24 h after middle cerebral artery occlusion (MCAO) was significantly smaller in the triple n/i/eNOSs-/- genotype as compared with wild-type genotype. Neurological deficit score and mortality rate were also significantly lower in the triple n/i/eNOSs-/- than in the WT genotype. In contrast, in the female, there was no significant difference in the cerebral infarct size in the two genotypes. In the male triple n/i/eNOSs-/- genotype, orchiectomy significantly increased the cerebral infarct size, and in the orchiectomized male triple n/i/eNOSs-/- genotype, treatment with testosterone significantly reduced it. Cyclopaedic and quantitative comparisons of mRNA expression levels in cerebral infarct lesions between the male wild-type and triple n/i/eNOSs-/- genotypes at 1 h after MCAO revealed significant involvements of decreased oxidative stress and mitigated mitochondrial dysfunction in the alleviated cerebral infarction in the male triple n/i/eNOSs-/- genotype.

CONCLUSIONS

These results provide the first evidence that the NOSs system exerts a deleterious effect against acute ischemic brain injury in the male.

Inhibition of Apoptosis in a Model of Ischemic Stroke Leads to Enhanced Cell Survival, Endogenous Neural Precursor Cell Activation and Improved Functional Outcomes

Stroke results in neuronal cell death, which causes long-term disabilities in adults. Treatment options are limited and rely on a narrow window of opportunity. Apoptosis inhibitors demonstrate efficacy in improving neuronal cell survival in animal models of stroke. However, many inhibitors non-specifically target apoptosis pathways and high doses are needed for treatment. We explored the use of a novel caspase-3/7 inhibitor, New World Laboratories (NWL) 283, with a lower IC50 than current caspase-3/7 inhibitors. We performed in vitro and in vivo assays to determine the efficacy of NWL283 in modulating cell death in a preclinical model of stroke. In vitro and in vivo assays show that NWL283 enhances cell survival of neural precursor cells. Delivery of NWL283 following stroke enhances endogenous NPC migration and leads to increased neurogenesis in the stroke-injured cortex. Furthermore, acute NWL283 administration is neuroprotective at the stroke injury site, decreasing neuronal cell death and reducing microglia activation. Coincident with NWL283 delivery for 8 days, stroke-injured mice exhibited improved functional outcomes that persisted following cessation of the drug. Therefore, we propose that NWL283 is a promising therapeutic warranting further investigation to enhance stroke recovery.

Sanpian decoction ameliorates cerebral ischemia-reperfusion injury by regulating SIRT1/ERK/HIF-1α pathway through in silico analysis and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathophysiological process involving multiple factors, and becomes the footstone of rehabilitation after ischemic stroke. Sanpian decoction (SPD) has exhibited protective effects against CIRI, migraine, and other cerebral vascular diseases. However, the underlying mechanisms have not been completely elucidated.

AIM OF THE STUDY

This study sought to explore the potential mechanisms underlying the effect of SPD against CIRI.

MATERIALS AND METHODS

High-performance liquid chromatography (HPLC) and ultra-high-performance liquid chromatography (UPLC) were carried out to determine the chemical constituents of SPD. A network pharmacology approach combined with experimental verification was conducted to elucidate SPD's multi-component, multi-target, and multi-pathway mechanisms in CIRI occurrence. The pharmacodynamics of the decoction was evaluated by establishing the rat model of middle cerebral artery occlusion/reperfusion (MCAO/R). In vivo and in vitro experiments were carried out, and the therapeutic effects of SPD were performed using 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (HE) staining, and Nissl staining. We used terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining and flow cytometry to evaluate cortex apoptosis. The quantification of mRNA and corresponding proteins were performed using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot respectively.

RESULTS

Our research showed that pretreatment with SPD improved neurological function and inhibited CIRI. Network pharmacology revealed that the hypoxia-inducible factor-1 (HIF-1) signaling pathway and mitogen-activated protein kinase (MAPK) signaling pathway-mediated apoptosis may be associated with CIRI. In vivo and in vitro experiments, we confirmed that SPD increased cerebral blood flow, improved neural function, and reduced neural apoptosis via up-regulating the expression of sirtuin 1 (SIRT1) and down-regulating phospho-extracellular regulated protein kinases (p-ERK)/ERK and HIF-1α levels in CIRI rats.

CONCLUSION

Taken together, the present study systematically revealed the potential targets and signaling pathways of SPD in the treatment of CIRI using in silico prediction and verified the therapeutic effects of SPD against CIRI via ameliorating apoptosis by regulating SIRT1/ERK/HIF-1α.

Blocking of microglia-astrocyte proinflammatory signaling is beneficial following stroke

Microglia and astrocytes play an important role in the neuroinflammatory response and contribute to both the destruction of neighboring tissue as well as the resolution of inflammation following stroke. These reactive glial cells are highly heterogeneous at both the transcriptomic and functional level. Depending upon the stimulus, microglia and astrocytes mount a complex, and specific response composed of distinct microglial and astrocyte substates. These substates ultimately drive the landscape of the initiation and recovery from the adverse stimulus. In one state, inflammation- and damage-induced microglia release tumor necrosis factor (TNF), interleukin 1α (IL1α), and complement component 1q (C1q), together "TIC." This cocktail of cytokines drives astrocytes into a neurotoxic reactive astrocyte (nRA) substate. This nRA substate is associated with loss of many physiological astrocyte functions (e.g., synapse formation and maturation, phagocytosis, among others), as well as a gain-of-function release of neurotoxic long-chain fatty acids which kill neighboring cells. Here we report that transgenic removal of TIC led to reduction of gliosis, infarct expansion, and worsened functional deficits in the acute and delayed stages following stroke. Our results suggest that TIC cytokines, and likely nRAs play an important role that may maintain neuroinflammation and inhibit functional motor recovery after ischemic stroke. This is the first report that this paradigm is relevant in stroke and that therapies against nRAs may be a novel means to treat patients. Since nRAs are evolutionarily conserved from rodents to humans and present in multiple neurodegenerative diseases and injuries, further identification of mechanistic role of nRAs will lead to a better understanding of the neuroinflammatory response and the development of new therapies.

Role of NLRP3 Inflammasome in Stroke Pathobiology: Current Therapeutic Avenues and Future Perspective

Neuroinflammation is a key pathophysiological feature of stroke-associated brain injury. A local innate immune response triggers neuroinflammation following a stroke via activating inflammasomes. The nucleotide-binding oligomerization domain leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome has been heavily implicated in stroke pathobiology. Following a stroke, several stimuli have been suggested to trigger the assembly of the NLRP3 inflammasome. Recent studies have advanced the understanding and revealed several new players regulating NLRP3 inflammasome-mediated neuroinflammation. This article discussed recent advancements in NLRP3 assembly and highlighted stroke-induced mitochondrial dysfunction as a major checkpoint to regulating NLRP3 activation. The NLRP3 inflammasome activation leads to caspase-1-dependent maturation and release of IL-1β, IL-18, and gasdermin D. In addition, genetic or pharmacological inhibition of the NLRP3 inflammasome activation and downstream signaling has been shown to attenuate brain infarction and improve the neurological outcome in experimental models of stroke. Several drug-like small molecules targeting the NLRP3 inflammasome are in different phases of development as novel therapeutics for various inflammatory conditions, including stroke. Understanding how these molecules interfere with NLRP3 inflammasome assembly is paramount for their better optimization and/or development of newer NLRP3 inhibitors. In this review, we summarized the assembly of the NLRP3 inflammasome and discussed the recent advances in understanding the upstream regulators of NLRP3 inflammasome-mediated neuroinflammation following stroke. Additionally, we critically examined the role of the NLRP3 inflammasome-mediated signaling in stroke pathophysiology and the development of therapeutic modalities to target the NLRP3 inflammasome-related signaling for stroke treatment.

3'-Daidzein Sulfonate Sodium Protects against Glutamate-induced Neuronal Injuries by Regulating NMDA Receptors

BACKGROUND

It was previously found that 3'-Daidzein Sulfonate Sodium (DSS) exhibits protective effects on cerebral ischemia/reperfusion injury (CI/RI).

AIM

This study aimed to explore the underlying molecular mechanisms involved in the neuroprotective effects of DSS against ischemic stroke.

METHODS

In this study, rats with transient middle cerebral artery occlusion (tMCAO) were used as an in vivo model, whereas PC12 cells treated with glutamate alone and rat primary cortical neurons treated with the combination of glutamate and glycine were used as in vitro models. Cell viability and lactate dehydrogenase (LDH) release were used to evaluate cell injury. Cell apoptosis was determined by flow cytometry. Quantitative polymerase chain reaction (qPCR), Western blotting, and immunofluorescent staining methods were used to determine the mRNA expressions and protein levels and location.

RESULTS

It was found that DSS significantly suppressed the impaired viability of PC12 cells induced by glutamate. DSS also increased cell viability while reducing the LDH release and apoptosis in primary cortical neurons injured by glutamate and glycine. In addition, DSS decreased GluN2B subunit expression while enhancing the expressions of GluN2A subunit and PSD95 in tMCAO rats' brains.

CONCLUSION

This study demonstrated that DSS protects against excitotoxic damage in neurons induced by CI/RI through regulating the expression of NMDA receptors and PSD95. Our findings provide experimental evidence for the potential clinical administration of DSS in ischemic stroke.

Efficacy and Mechanism Study of 6S-5-Methyltetrahydrofolate-Calcium Against Telencephalon Infarction Injury in Zebrafish Model of Ischemic Stroke

Ischemic stroke is a heterogeneous brain injury with complex pathophysiology and it is also a time sensitive neurological injury disease. At present, the treatment options for ischemic stroke are still limited. 6S-5-methyltetrahydrofolate-calcium (MTHF-Ca) is the calcium salt of the predominant form of dietary folate in circulation. MTHF-Ca has potential neuroprotective effect on neurocytes, but whether it can be used for ischemic stroke treatment remains unknown. We established zebrafish ischemic stroke model through photothrombotic method to evaluate the protective effect of MTHF-Ca on the ischemic brain injury of zebrafish. We demonstrated that MTHF-Ca reduced the brain damage by reducing motor dysfunction and neurobehavioral defects of zebrafish with telencephalon infarction injury. MTHF-Ca counteracted oxidative damages after Tel injury by increasing the activities of GSH-Px and SOD and decreasing the content of MDA. RNA-seq and RT-qPCR results showed that MTHF-Ca played a neuroprotective role by alleviating neuroinflammation, inhibiting blood coagulation, and neuronal apoptosis processes. Overall, we have demonstrated that MTHF-Ca has neuroprotective effect in ischemic stroke and can be used as a potential treatment for ischemic stroke.

Identification of Hub Genes and Pathways of Middle Cerebral Artery Occlusion in Aged Rats Using the Gene Expression Omnibus Database

Stroke remained the leading cause of disability in the world, and the most important non-modifiable risk factor was age. The treatment of stroke for elder patients faced multiple difficulties due to its complicated pathogenesis and mechanism. Therefore, we aimed to identify the potential differentially expressed genes (DEGs) and singnalling pathways for aged people of stroke. To compare the DEGs in the aged rats with or without middle cerebral artery occlusion (MCAO) and to analyse the important genes and the key signaling pathways involved in the development of cerebral ischaemia in aged rats. The Gene Expression Omnibus (GEO) analysis tool was used to analyse the DEGs in the GSE166162 dataset of aged MCAO rats compared with aged sham rats. Differential expression analysis was performed in aged MCAO rats and sham rats using limma. In addition, the 74 DEGs (such as Fam111a, Lcn2, Spp1, Lgals3 and Gpnmb were up-regulated; Egr2, Nr4a3, Arc, Klf4 and Nr4a1 were down-regulated) and potential compounds corresponding to the top 20 core genes in the Protein-Protein Interaction (PPI) network was constructed using the STRING database (version 12.0). Among these 30 compounds, resveratrol, cannabidiol, honokiol, fucoxanthin, oleandrin and tyrosol were significantly enriched. These DEGs were subjected to Gene Ontology (GO) function analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to determine the most significantly enriched pathway in aged MCAO rats. Moreover, innate immune response, the complement and coagulation cascades signaling pathway, the IL-17 and other signaling pathways were significantly correlated with the aged MCAO rats. Our study indicates that multiple genes and pathological processes involved in the aged people of stroke. The immune response might be the key pathway in the intervention of cerebral infarction in aged people.

Potential role of Nigella Sativa and its Constituent (Thymoquinone) in Ischemic Stroke

Ischemic stroke is one of the major causes of global mortality, which puts great demands on health systems and social welfare. Ischemic stroke is a complex pathological process involving a series of mechanisms such as ROS accumulation, Ca2+ overload, inflammation, and apoptosis. The lack of effective and widely applicable pharmacological treatments for ischemic stroke patients has led scientists to find new treatments. The use of herbal medicine, as an alternative or complementary therapy, is increasing worldwide. For centuries, our ancestors had known the remedial nature of Nigella sativa (Family Ranunculaceae) and used it in various ways, either as medicine or as food. Nowadays, N. sativa is generally utilized as a therapeutic plant all over the world. Most of the therapeutic properties of this plant are attributed to the presence of thymoquinone which is the major biological component of the essential oil. The present review describes the pharmacotherapeutic potential of N. sativa in ischemic stroke that has been carried out by various researchers. Existing literature highlights the protective effects of N. sativa as well as thymoquinone in ischemia stroke via different mechanisms including anti-oxidative stress, anti-inflammation, anti-apoptosis, neuroprotective, and vascular protective effects. These properties make N. sativa and thymoquinone promising candidates for developing potential agents for the prevention and treatment of ischemic stroke.

Functional Roles of Mesenchymal Stem Cell-derived Exosomes in Ischemic Stroke Treatment

Stroke is a life-threatening disease and one of the leading causes of death and physical disability worldwide. Currently, no drugs on the market promote neural recovery after stroke insult, and spontaneous remodeling processes are limited to induce recovery in the ischemic regions. Therefore, promoting a cell-based therapy has been needed to elevate the endogenous recovery process. Mesenchymal stem cells (MSCs) have been regarded as candidate cell sources for therapeutic purposes of ischemic stroke, and their therapeutic effects are mediated by exosomes. The microRNA cargo in these extracellular vesicles is mostly responsible for the positive effects. When it comes to the therapeutic viewpoint, MSCsderived exosomes could be a promising therapeutic strategy against ischemic stroke. The aim of this review is to discuss the current knowledge around the potential of MSCs-derived exosomes in the treatment of ischemic stroke.

Environmental Enrichment for Stroke and Traumatic Brain Injury: Mechanisms and Translational Implications

Acquired brain injuries, such as ischemic stroke, intracerebral hemorrhage (ICH), and traumatic brain injury (TBI), can cause severe neurologic damage and even death. Unfortunately, currently, there are no effective and safe treatments to reduce the high disability and mortality rates associated with these brain injuries. However, environmental enrichment (EE) is an emerging approach to treating and rehabilitating acquired brain injuries by promoting motor, sensory, and social stimulation. Multiple preclinical studies have shown that EE benefits functional recovery, including improved motor and cognitive function and psychological benefits mediated by complex protective signaling pathways. This article provides an overview of the enriched environment protocols used in animal models of ischemic stroke, ICH, and TBI, as well as relevant clinical studies, with a particular focus on ischemic stroke. Additionally, we explored studies of animals with stroke and TBI exposed to EE alone or in combination with multiple drugs and other rehabilitation modalities. Finally, we discuss the potential clinical applications of EE in future brain rehabilitation therapy and the molecular and cellular changes caused by EE in rodents with stroke or TBI. This article aims to advance preclinical and clinical research on EE rehabilitation therapy for acquired brain injury. © 2024 American Physiological Society. Compr Physiol 14:5291-5323, 2024.

Advances in nitric oxide regulators for the treatment of ischemic stroke

Ischemic stroke (IS) is a life-threatening disease worldwide. Nitric oxide (NO) derived from l-arginine catalyzed by NO synthase (NOS) is closely associated with IS. Three isomers of NOS (nNOS, eNOS and iNOS) produce different concentrations of NO, resulting in quite unlike effects during IS. Of them, n/iNOSs generate high levels of NO, detrimental to brain by causing nerve cell apoptosis and/or necrosis, whereas eNOS releases small amounts of NO, beneficial to the brain via increasing cerebral blood flow and improving nerve function. As a result, a large variety of NO regulators (NO donors or n/iNOS inhibitors) have been developed for fighting IS. Regrettably, up to now, no review systematically introduces the progresses in this area. This article first outlines dynamic variation rule of NOS/NO in IS, subsequently highlights advances in NO regulators against IS, and finally presents perspectives based on concentration-, site- and timing-effects of NO production to promote this field forward.

Trigeminal nerve stimulation: a current state-of-the-art review

Nearly 5 decades ago, the effect of trigeminal nerve stimulation (TNS) on cerebral blood flow was observed for the first time. This implication directly led to further investigations and TNS' success as a therapeutic intervention. Possessing unique connections with key brain and brainstem regions, TNS has been observed to modulate cerebral vasodilation, brain metabolism, cerebral autoregulation, cerebral and systemic inflammation, and the autonomic nervous system. The unique range of effects make it a prime therapeutic modality and have led to its clinical usage in chronic conditions such as migraine, prolonged disorders of consciousness, and depression. This review aims to present a comprehensive overview of TNS research and its broader therapeutic potentialities. For the purpose of this review, PubMed and Google Scholar were searched from inception to August 28, 2023 to identify a total of 89 relevant studies, both clinical and pre-clinical. TNS harnesses the release of vasoactive neuropeptides, modulation of neurotransmission, and direct action upon the autonomic nervous system to generate a suite of powerful multitarget therapeutic effects. While TNS has been applied clinically to chronic pathological conditions, these powerful effects have recently shown great potential in a number of acute/traumatic pathologies. However, there are still key mechanistic and methodologic knowledge gaps to be solved to make TNS a viable therapeutic option in wider clinical settings. These include bimodal or paradoxical effects and mechanisms, questions regarding its safety in acute/traumatic conditions, the development of more selective stimulation methods to avoid potential maladaptive effects, and its connection to the diving reflex, a trigeminally-mediated protective endogenous reflex. The address of these questions could overcome the current limitations and allow TNS to be applied therapeutically to an innumerable number of pathologies, such that it now stands at the precipice of becoming a ground-breaking therapeutic modality.

Recent Advances in Chemically Engineered Nanostructures Impact on Ischemic Stroke Treatment

Stroke is a serious public health problem that raises expenses for society and causes long-term impairment and death. However, due to restricted blood-brain barrier (BBB) penetration, there are few treatment alternatives for treating stroke. Recanalization techniques, neuroprotective medications, and recovery techniques are all forms of treatment. The ischemic stroke treatment window is too narrow for logical and efficient therapy, and detection is possible only in advanced stages. BBB integrity disruption, neurotoxicity, and the brief half-life of therapeutic thrombolytics are the key molecular pathogenic causes of ischemic stroke. Existing neuroprotective drugs' inability to promote the recovery of ischemic brain tissue after a stroke is another factor that contributes to the disease's progression, chronic nature, and severity. A possible approach to getting around these medication restrictions and boosting the effectiveness of therapies is nanotechnology. In order to get around these drug-related restrictions and boost the effectiveness of therapies for neurological conditions such as stroke, nanotechnology has emerged as a viable option. These problems might be avoided by using nanoparticle-based methods to create a thrombolytic medication that is safe to use after the tissue plasminogen activator (tPA) treatment window has passed. The idea of using biomimetic nanoparticles in the future for the treatment of ischemic stroke through immunotherapy and stem cell therapy is highlighted, along with recent advancements in the study of nanomaterials for ischemic stroke diagnostics and treatment.

Biomimetic nanoparticles in ischemic stroke therapy

Abstract

Ischemic stroke is one of the most severe neurological disorders with limited therapeutic strategies. The utilization of nanoparticle drug delivery systems is a burgeoning field and has been widely investigated. Among these, biomimetic drug delivery systems composed of biogenic membrane components and synthetic nanoparticles have been extensively highlighted in recent years. Biomimetic membrane camouflage presents an effective strategy to prolong circulation, reduce immunogenicity and enhance targeting. For one thing, biomimetic nanoparticles reserve the physical and chemical properties of intrinsic nanoparticle. For another, the biological functions of original source cells are completely inherited. Compared to conventional surface modification methods, this approach is more convenient and biocompatible. In this review, membrane-based nanoparticles derived from different donor cells were exemplified. The prospect of future biomimetic nanoparticles in ischemic stroke therapy was discussed.

Graphic abstract

CircCRIM1/microRNA-141-3p/thioredoxin-binding protein axis mediates neuronal apoptosis after cerebral ischemia-reperfusion

Numerous studies have indicated enrichment of circular RNA (circRNA) in the brain takes on a momentous role in cerebral ischemia-reperfusion (CIR) injury. A recent study discovered a novel circCRIM1, was highly expressed in the middle cerebral artery occlusion-reperfusion (MCAO/R) model. Nevertheless, its specific biological function remained unknown. The study was to explore circCRIM1 in CIR-induced neuronal apoptosis. As measured, circCRIM1 and TXNIP were up-regulated, while miR-141-3p was down-regulated in MCAO/R mouse model and OGD/R SH-SY5Y cells. Depleting circCRIM1 reduced the number of apoptotic neurons in MCAO/R rats, increased the number of Nissl bodies, prevented reactive oxygen species production and oxidative stress imbalance in brain tissues, repressed cleaved caspase-3, Bax, and Cyto C protein levels and increased Bcl-2 levels. Overexpression of circCRIM1 further repressed neuronal activity and accelerated apoptosis in OGD/R model, disrupted redox balance. Depleting circCRIM1 had the opposite effect in OGD/R model. Knocking down miR-141-3p or TXNIP weakened the effects of knocking down circCRIM1 or overexpressing circCRIM1, separately. Mechanistically, circCRIM1 exerted an active role in CIR injury via miR-141-3p to mediate TXNIP. All in all, the circCRIM1/miR-141-3p/TXNIP axis might be a latent therapeutic target for CIR injury.

Design and synthesis of 9-phenanthranilamide derivatives and the study of anti-inflammatory, antioxidant and neuroprotective activities

Oxidative stress and a series of excessive inflammatory responses are major obstacles to neurological functional recovery after ischemic stroke. In this study, we synthesized several novel 9-phenanthranilamide derivatives and evaluated their anti-inflammatory and antioxidant activities. Among the initially screened compounds, most could strongly inhibi lipopolysaccharide (LPS)-stimulated production of IL-1β, IL-6 and TNF-α in microglial cells. Additionally, compounds 8b, 8q, 8r and 8s significantly inhibited the production of NO, and they also had dose-dependent protective effects on PC12 neuronal cells induced by H2O2. The antineuroinflammatory effects of 8r and 8s were associated with the downregulation of LPS-induced inflammatory mediators of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and both compounds inhibited the NF-κB signaling pathway. Further examinations showed that 8s had a significant neuroprotective effect on rats with middle cerebral artery occlusion (MCAO). It decreased the infarct volume and the neurological deficit score. Overall, our results suggested that compound 8s might be a promising agent for stroke treatment.

Circ_0059662 exerts a positive role in oxygen-glucose deprivation/reoxygenation-induced SK-N-SH cell injury

Circular RNA (circRNA) is identified as a potential regulator of ischemic stroke (IS) progression. Through GEO database screening, it was found that circ_0059662 was highly expressed in acute IS patients. However, whether circ_0059662 participated in the IS process has not been studied. Oxygen-glucose deprivation/reoxygenation (OGD/R)-induced SK-N-SH cells were established to mimic IS cell models. The expression of circ_0059662, miR-579-3p, and ETS proto-oncogene 1 (ETS1) was measured via quantitative real-time PCR. Cell counting kit 8 assay, EdU assay and flow cytometry were utilized to detect cell proliferation and apoptosis. Western blot was employed to measure protein expression. ELISA was used to detect the levels of inflammation factors, and oxidative stress was determined by assessing SOD activity and MDA level. The relationship between miR-579-3p and circ_0059662 or ETS1 was examined via dual-luciferase reporter assay, RNA pull-down assay and RIP assay. Circ_0059662 was a circular RNA with highly expression in OGD/R-induced SK-N-SH cells. In OGD/R-induced cell injury, circ_0059662 knockdown promoted cell proliferation, and inhibited cell apoptosis, inflammation and oxidative stress. Circ_0059662 served as miR-579-3p sponge to positively regulate ETS1 expression. MiR-579-3p inhibitor and ETS1 overexpression could reverse the inhibition effect of circ_0059662 knockdown on OGD/R-induced cell injury. Besides, MiR-579-3p also could relieve OGD/R-induced SK-N-SH cell apoptosis, inflammation and oxidative stress by targeting ETS1. Our findings indicated that circ_0059662 knockdown alleviated OGD/R-induced SK-N-SH cell injury by sponging miR-579-3p to regulate ETS1 expression.

Microglia dynamic response and phenotype heterogeneity in neural regeneration following hypoxic-ischemic brain injury

Hypoxic-ischemic brain injury poses a significant threat to the neural niche within the central nervous system. In response to this pathological process, microglia, as innate immune cells in the central nervous system, undergo rapid morphological, molecular and functional changes. Here, we comprehensively review these dynamic changes in microglial response to hypoxic-ischemic brain injury under pathological conditions, including stroke, chronic intermittent hypoxia and neonatal hypoxic-ischemic brain injury. We focus on the regulation of signaling pathways under hypoxic-ischemic brain injury and further describe the process of microenvironment remodeling and neural tissue regeneration mediated by microglia after hypoxic-ischemic injury.

Exosomal miRNAs as Biomarkers of Ischemic Stroke

Exosomes are small lipid bilayer membrane particles released from all living cells into the extracellular environment. They carry several molecules and have a critical role in cell-cell communication under physiological and pathological conditions. In recent decades, exosomes, and especially their cargo, have emerged as a promising tool for several clinical conditions. However, the literature has become increasingly unambiguous in defining the role of exosomes in chronic cerebrovascular diseases. Because they can pass through the blood-brain barrier, they have great potential to reflect intracerebral changes. They can, thus, provide valuable insight into the mechanisms of central nervous system diseases. The purpose of this review is to describe the literature on the role of exosomal miRNA, which represents the most widely investigated exosomal biomarker, in strokes. First, we provide an overview of exosomes, from biology to isolation and characterization. Then, we describe the relationship between exosomes and stroke pathogenesis. Finally, we summarize the human studies evaluating exosomal miRNA biomarkers of stroke. Although the collective literature supports the potential use of exosomal miRNA as biomarkers of ischemic stroke, there are still several limitations hampering their introduction into clinical practice.

CircFKBP3 absence alleviates oxygen glucose deprivation-induced function loss of human brain microvascular endothelial cells in vitro via governing the miR-766-3p/TRAF3 axis

BACKGROUND

Brain microvascular endothelial cell (BMEC) functions loss is a key event in the development of ischemic stroke, which may be affected by the dysregulation of circular RNAs (circRNAs). We aimed to unveil the role of circRNA FKBP Prolyl Isomerase 3 (circFKBP3) in cell models of ischemic stroke.

METHODS

Cell models of ischemic stroke were constructed in human BEMCs (HBMECs) with the treatment of oxygen glucose deprivation (OGD). Quantitative real-time PCR (qPCR) and western blotting were conducted for expression analysis of circFKBP3, miR-766-3p and TNF receptor associated factor 3 (TRAF3). CCK-8, transwell, wound healing, flow cytometry, tube formation and ELISA assays were implemented to monitor cell viability, migration, apoptosis, angiogenesis and inflammation production. The putative binding relationship between miR-766-3p and circFKBP3 or TRAF3 was validated by dual-luciferase, RIP and pull-down assays.

RESULTS

CircFKBP3 expression was elevated in OGD-treated HBMECs. OGD suppressed HBMEC viability, migration, angiogenesis, and provoked cell apoptosis and inflammation production, while knockdown of circFKBP3 attenuated these effects. CircFKBP3 interacted with miR-766-3p, and circFKBP3 absence-repressed HBMEC function loss and inflammation were recovered by miR-766-3p inhibition. CircFKBP3 targeted miR-766-3p to regulate TRAF3 expression. MiR-766-3p enrichment-repressed HBMEC function loss and inflammation were recovered by TRAF3 overexpression.

CONCLUSION

CircFKBP3 absence alleviated OGD-induced function loss and inflammatory responses of HBMECs via governing the miR-766-3p/TRAF3 axis.

Changes of gut microbiota in patients at different phases of stroke

AIMS

Gut dysbiosis appears rapidly after acute stroke and may affect the prognosis, whereas changes in gut microbiota with gradual recovery from stroke are unknown and rarely studied. The purpose of this study is to explore the characteristics of gut microbiota changes over time after stroke.

METHODS

Stroke patients and healthy subjects were selected to compare the clinical data and gut microbiota of the patient group in two phases with that of healthy subjects and 16S rRNA gene sequencing was used to search the differences of gut microbiota in subjects.

RESULTS

Compared with the healthy subjects, the subacute patients mainly decreased the abundance of some gut microbial communities, while the decreased communities reduced and more communities increased the abundance in the convalescent patients. The abundance of Lactobacillaceae increased in both phases in patient group, while Butyricimona, Peptostreptococaceae and Romboutsia decreased in both phases. Correlation analysis found that the MMSE scores of patients in the two phases had the greatest correlation with the gut microbiota.

CONCLUSION

Gut dysbiosis still existed in patients in the subacute phase and convalescent phase, and gradually improved with the recovery of stroke. Gut microbiota may affect the prognosis of stroke by affecting BMI and/or related indicators, and there is a strong correlation between gut microbiota and cognitive function after stroke.

Crebanine ameliorates ischemia-reperfusion brain damage by inhibiting oxidative stress and neuroinflammation mediated by NADPH oxidase 2 in microglia

BACKGROUND

The urgent challenge for ischemic stroke treatment is the lack of effective neuroprotectants that target multiple pathological processes. Crebanine, an isoquinoline-like alkaloid with superior pharmacological activities, presents itself as a promising candidate for neuroprotection. However, its effects and mechanisms on ischemic stroke remain unknown.

METHODS

The effects of crebanine on brain damage following ischemic stroke were evaluated using the middle cerebral artery occlusion and reperfusion (MCAO/R) model. Mechanism of action was investigated using both MCAO/R rats and lipopolysaccharide (LPS)-activated BV-2 cells.

RESULTS

We initially demonstrated that crebanine effectively ameliorated the neurological deficits in MCAO/R rats, while also reducing brain edema and infarction. Treatment with crebanine resulted in the up-regulation of NeuN+ fluorescence density and down-regulation of FJB+ cell count, and mitigated synaptic damage. Crebanine attenuated the hyperactivation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (NOX2) by downregulating NADP+ and NADPH levels, suppressing gp91phox and p47phox expressions, and reducing p47phox membrane translocation in Iba-1+ cells. Additionally, crebanine reduced the quantity of Iba-1+ cells and protein expression. Correlation analysis has demonstrated that the inhibition of NOX2 activation in microglia is beneficial for mitigating I/R brain injuries. Moreover, crebanine exhibited significant antioxidant properties by down-regulating the expression of superoxide anion and intracellular reactive oxygen species in vivo and in vitro, and reducing lipid and DNA peroxidation. Crebanine exerted anti-inflammatory effect, as evidenced by the reduction in the expressions of nitric oxide, interleukin 1β, tumor necrosis factor α, interleukin 6, and inducible nitric oxide synthase. The effect of crebanine was achieved through the suppression of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPK) signaling pathway. This is supported by evidence showing reduced NF-κB p65 promoter activity and nucleus translocation, as well as suppressed IκBα phosphorylation and degradation. Additionally, it inhibited the phosphorylation of ERK, JNK, and p38 MAPKs. Importantly, the anti-oxidative stress and neuroinflammation effects of crebanine were further enhanced after silencing gp91phox and p47phox.

CONCLUSION

Crebanine alleviated the brain damages of MCAO/R rats by inhibiting oxidative stress and neuroinflammation mediated by NOX2 in microglia, implying crebanine might be a potential natural drug for the treatment of cerebral ischemia.

Scientific Landscape of Oxidative Stress in Stroke: From a Bibliometric Analysis to an in-Depth Review

Stroke is an acute cerebrovascular disease resulting from either obstruction or rupture of a blood vessel in the brain. Oxidative stress (OS), referred to a status where cellular oxidative capacities overwhelm antioxidative defenses, is involved in the pathophysiology of stroke. The bibliometric analysis and in-depth review aim to depict the research trend of OS in stroke. Relevant scientific publications were acquired from the Web of Science Core Collection database. Scientific landscape of OS in stroke was illustrated by general quantitative trend, impactful journals, and co-authorship of various academic units (i.e., countries/regions, organizations, and authors). Furthermore, theme analysis predicting the hot research issues and frontiers was performed. 15,826 documents regarding OS in stroke were obtained over a time span of more than 20 years from 1992 to 2021. The overall tendency of publication counts was continuously on the rise. Bibliometric analysis indicated China and the United States were predominant in this study field, as reflected by their high publication counts and intensive collaboration with other countries. Current key research areas of OS in stroke may lie in the investigation of neuroinflammation, and interaction among multiple cell death mechanisms including apoptosis, autophagy, and ferroptosis to search for effective treatments. Moreover, another hot topic could be the association between air pollution and stroke, and its underlying mechanisms. As the exploration of OS in stroke is speculated to be a continuous hot spot in the future, this article may be helpful for researchers to conduct future studies with the understanding of influential academic forces and research highlights.