Signaling pathways involved in ischemic stroke: molecular mechanisms and therapeutic interventions

Cell polarization in ischemic stroke: molecular mechanisms and advances

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as 'cell polarization.' There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations (microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

Substance basis and pharmacological mechanism of heat-clearing herbs in the treatment of ischaemic encephalopathy: a systematic review and network pharmacology

BACKGROUND AND OBJECTIVE

Ischaemic encephalopathy is a common cerebrovascular disease caused by insufficient blood supply to the cerebral vessels. The ischaemic encephalopathy is closely associated with the development of many chronic diseases such as obesity, hypertension and diabetes. Neurotrophic therapy has become the main therapeutic strategy for ischaemic encephalopathy. However, neurotrophic drugs only slightly recover the neurological function of patients, and their long-term efficacy is uncertain. Previous reports revealed that the active ingredients of natural medicines play important roles in the treatment of cerebral ischemia. In this study, we reviewed clearing herbs with anti-ischaemic encephalopathy functions using the data from quantitative statistical and network pharmacological exploration methods. We also discussed the different bioactive components and pharmacological effects of these herbs.

METHODS

First, we collected Chinese herbal prescriptions against ischaemic encephalopathy in four databases. Then, we statistically analysed the frequency of application of heat-clearing herbs to obtain the commonly used heat-clearing herbs against ischaemic encephalopathy, and classified them according to their efficacy according to the statistical results, to summarize the mechanism of anti-ischaemic effects of different bioactive components; Second, the network database was used to obtain the above components of heat-clearing Chinese medicines and their corresponding targets of action, disease targets of ischaemic stroke; Venny 2.1.0 was used to obtain component-disease target intersections; Cytoscape was used to construct the 'Drug-Active Ingredient-Target Network Graph '; DAVID was used for GO and KEGG enrichment analysis.

RESULTS

Literature and database screening involved 149 prescriptions, with a total of 269 flavours of Chinese medicines and 20 flavours of single-flavour heat-clearing Chinese medicines; The top nine in terms of frequency of use were Radix Paeoniae Rubra、Rehmanniae Radix Praeparata、Figwort Root、Cortex Moutan、Scutellariae Radix、Coptidis Rhizoma、Gardeniae Fructus、Cassiae Semen、Lonicerae Japonicae Flos. The common components obtained from network pharmacology were beta-sitosterol, quercetin, and stigmasterol, which mainly act on key targets such as RELA, AKT1, JUN, PRKACA, PTGS2, RAF1 and CHUK; and their active ingredients are mainly involved in signalling pathways such as Calcium, PI3K-Ak, MAPK, cAMP, IL-17, HIF-1, TNF, T-cell receptor, NF-kappa B and JAK-STAT.

CONCLUSIONS

Heat-clearing herbs are useful and promising for the protection against and prevention of ischemic encephalopathy. The results of the network pharmacological studies are similar to the mechanisms of anti-ischemic encephalopathy of the active ingredients of the purgative herbs we have listed; Thin either directly protects cerebrovascular tissues by improving vascular permeability and reducing the area of infarcted tissues, or produces protective effects through molecular signaling pathways. It can be seen that the components of heat-clearing Chinese medicines can exert cerebroprotective effects through multiple pathways, which provides us with a reference for further development and study of heat-clearing Chinese medicines in the treatment of ischemic cerebrovascular diseases.

Association of DNA methylation/demethylation with the functional outcome of stroke in a hyperinflammatory state

JOURNAL/nrgr/04.03/01300535-202410000-00024/figure1/v/2024-02-06T055622Z/r/image-tiff Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effect of DNA methylation on stroke at high levels of inflammation is unclear. In this study, we constructed a hyperinflammatory cerebral ischemia mouse model and investigated the effect of hypomethylation and hypermethylation on the functional outcome. We constructed a mouse model of transient middle cerebral artery occlusion and treated the mice with lipopolysaccharide to induce a hyperinflammatory state. To investigate the effect of DNA methylation on stroke, we used small molecule inhibitors to restrain the function of key DNA methylation and demethylation enzymes. 2,3,5-Triphenyltetrazolium chloride staining, neurological function scores, neurobehavioral tests, enzyme-linked immunosorbent assay, quantitative reverse transcription PCR and western blot assay were used to evaluate the effects after stroke in mice. We assessed changes in the global methylation status by measuring DNA 5-mc and DNA 5-hmc levels in peripheral blood after the use of the inhibitor. In the group treated with the DNA methylation inhibitor, brain tissue 2,3,5-triphenyltetrazolium chloride staining showed an increase in infarct volume, which was accompanied by a decrease in neurological scores and worsening of neurobehavioral performance. The levels of inflammatory factors interleukin 6 and interleukin-1 beta in ischemic brain tissue and plasma were elevated, indicating increased inflammation. Related inflammatory pathway exploration showed significant overactivation of nuclear factor kappa B. These results suggested that inhibiting DNA methylation led to poor functional outcome in mice with high inflammation following stroke. Further, the effects were reversed by inhibition of DNA demethylation. Our findings suggest that DNA methylation regulates the inflammatory response in stroke and has an important role in the functional outcome of hyperinflammatory stroke.

The advantages of multi-level omics research on stem cell-based therapies for ischemic stroke

Stem cell transplantation is a potential therapeutic strategy for ischemic stroke. However, despite many years of preclinical research, the application of stem cells is still limited to the clinical trial stage. Although stem cell therapy can be highly beneficial in promoting functional recovery, the precise mechanisms of action that are responsible for this effect have yet to be fully elucidated. Omics analysis provides us with a new perspective to investigate the physiological mechanisms and multiple functions of stem cells in ischemic stroke. Transcriptomic, proteomic, and metabolomic analyses have become important tools for discovering biomarkers and analyzing molecular changes under pathological conditions. Omics analysis could help us to identify new pathways mediated by stem cells for the treatment of ischemic stroke via stem cell therapy, thereby facilitating the translation of stem cell therapies into clinical use. In this review, we summarize the pathophysiology of ischemic stroke and discuss recent progress in the development of stem cell therapies for the treatment of ischemic stroke by applying multi-level omics. We also discuss changes in RNAs, proteins, and metabolites in the cerebral tissues and body fluids under stroke conditions and following stem cell treatment, and summarize the regulatory factors that play a key role in stem cell therapy. The exploration of stem cell therapy at the molecular level will facilitate the clinical application of stem cells and provide new treatment possibilities for the complete recovery of neurological function in patients with ischemic stroke.

Regulating NCOA4-Mediated Ferritinophagy for Therapeutic Intervention in Cerebral Ischemia-Reperfusion Injury

Ischemic stroke presents a global health challenge, necessitating an in-depth comprehension of its pathophysiology and therapeutic strategies. While reperfusion therapy salvages brain tissue, it also triggers detrimental cerebral ischemia-reperfusion injury (CIRI). In our investigation, we observed the activation of nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy in an oxygen-glucose deprivation/reoxygenation (OGD/R) model using HT22 cells (P < 0.05). This activation contributed to oxidative stress (P < 0.05), enhanced autophagy (P < 0.05) and cell death (P < 0.05) during CIRI. Silencing NCOA4 effectively mitigated OGD/R-induced damage (P < 0.05). These findings suggested that targeting NCOA4-mediated ferritinophagy held promise for preventing and treating CIRI. Subsequently, we substantiated the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway effectively regulated the NCOA4-mediated ferritinophagy, by applying the cGAS inhibitor RU.521 and performing NCOA4 overexpression (P < 0.05). Suppressing the cGAS-STING pathway efficiently curtailed ferritinophagy (P < 0.05), oxidative stress (P < 0.05), and cell damage (P < 0.05) of CIRI, while NCOA4 overexpression could alleviate this effect (P < 0.05). Finally, we elucidated the specific molecular mechanism underlying the protective effect of the iron chelator deferoxamine (DFO) on CIRI. Our findings revealed that DFO alleviated hypoxia-reoxygenation injury in HT22 cells through inhibiting NCOA4-mediated ferritinophagy and reducing ferrous ion levels (P < 0.05). However, the protective effects of DFO were counteracted by cGAS overexpression (P < 0.05). In summary, our results indicated that the activation of the cGAS-STING pathway intensified cerebral damage during CIRI by inducing NCOA4-mediated ferritinophagy. Administering the iron chelator DFO effectively attenuated NCOA4-induced ferritinophagy, thereby alleviating CIRI. Nevertheless, the role of the cGAS-STING pathway in CIRI regulation likely involves intricate mechanisms, necessitating further validation in subsequent investigations.

Precisely targeted drug delivery by mesenchymal stem cells-based biomimetic liposomes to cerebral ischemia-reperfusion injured hemisphere

The precise and targeted delivery of therapeutic agents to the lesion sites remains a major challenge in treating brain diseases represented by ischemic stroke. Herein, we modified liposomes with mesenchymal stem cells (MSC) membrane to construct biomimetic liposomes, termed MSCsome. MSCsome (115.99 ± 4.03 nm) exhibited concentrated accumulation in the cerebral infarcted hemisphere of mice with cerebral ischemia-reperfusion injury, while showing uniform distribution in the two cerebral hemispheres of normal mice. Moreover, MSCsome exhibited high colocalization with damaged nerve cells in the infarcted hemisphere, highlighting its advantageous precise targeting capabilities over liposomes at both the tissue and cellular levels. Leveraging its superior targeting properties, MSCsome effectively delivered Dl-3-n-butylphthalide (NBP) to the injured hemisphere, making a single-dose (15 mg/kg) intravenous injection of NBP-encapsulated MSCsome facilitate the recovery of motor functions in model mice by improving the damaged microenvironment and suppressing neuroinflammation. This study underscores that the modification of the MSC membrane notably enhances the capacity of liposomes for precisely targeting the injured hemisphere, which is particularly crucial in treating cerebral ischemia-reperfusion injury.

Intervention of exogenous VEGF protect brain microvascular endothelial cells from hypoxia-induced injury by regulating PLCγ/RAS/ERK and PI3K/AKT pathways

Ischemic stroke rapidly increases the expression level of vascular endothelial growth factor (VEGF), which promotes neovascularization during hypoxia. However, the effect and mechanism of VEGF intervention on cerebrovascular formation remain unclear. Therefore, our research discussed the protective effect of exogenous VEGF on cells in hypoxia environment in cerebral microvascular endothelial cells, simulating ischemic stroke in hypoxic environment. Firstly, we detected the proliferation and apoptosis of cerebral microvascular endothelial cells under hypoxia environment, as well the expression levels of VEGF-E, vascular endothelial growth factor re-ceptor-2 (VEGFR-2), BCL2, PRKCE and PINK1. Moreover, immunofluorescence and western blotting were used to verify the regulation of exogenous VEGF-E on VEGFR-2 expression in hypoxic or normal oxygen environment. Lastly, we manipulated the concentration of VEGF-E in the culture medium to investigate its impact on phospholipase Cγ1 (PLCγ1)/extracellular signaling regulatory protein kinase (ERK) -1/2 and protein kinase B (AKT) pathways. Additionally, we employed a PLCγ1 inhibitor (U73122) to investigate its impact on proliferation and PLCγ1/ERK pathways. The results show that hypoxia inhibited the proliferation of cerebral microvascular endothelial cells, promoted cell apoptosis, significantly up-regulated the expression of VEGF-E, VEGFR-2, PRKCE and PINK1, but down-regulated the expression of BCL2. Interference from exogenous VEGF-E activated PLCγ1/ERK-1/2 and AKT pathways, promoting cell proliferation and inhibiting apoptosis of hypoxic brain microvascular endothelial cells. In summary, exogenous VEGF-E prevents hypoxia-induced damage to cerebral microvascular endothelial cells by activating the PLCγ1/ERK and AKT pathways. This action inhibits the apoptosis pathway in hypoxic cerebral microvascular endothelial cells, thereby safeguarding the blood-brain barrier and the nervous system.

Cerebral [18F]AIF-FAPI-42-Based PET Imaging of Fibroblast Activation Protein for Non-invasive Quantification of Fibrosis After Ischemic Stroke

The development of fibrosis after injury to the brain or spinal cord limits the regeneration of the central nervous system in adult mammals. However, the extent of fibrosis in the injured brain has not been systematically investigated in mammals in vivo. This study aimed to assess whether [18F]AlF-FAPI-42-based cerebral positron emission tomography (PET) can be utilized to assess the extent of fibrosis in ischemic regions of the brain in vivo. Sprague-Dawley rats underwent permanent occlusion of the right middle cerebral artery (MCAO). On days 3, 7, 14, and 21 after MCAO, the uptake of [18F]AlF-FAPI-42 in the ischemic region of the brain in the MCAO groups surpassed that in the control group (day 0). The specific expression of fibroblast activation protein-α (FAP) in ischemic regions of the brain was also confirmed in immunohistofluorescence experiments in vitro. [18F]AlF-FAPI-42 intensity correlated with the density of collagen deposition in the ischemic hemisphere (p < 0.001). [18F]AlF-FAPI-42 PET/CT imaging demonstrated a specific uptake of radioactivity in the infarcted area in an ischemic stroke patient. PET imaging by using [18F]AlF-FAPI-42 offers a promising non-invasive method for monitoring the progression of cerebral fibrosis caused by ischemic stroke and may facilitate the clinical management of stroke patients. Trial registration: chictr.org.cn ChiCTR2200059004. Registered April 22, 2022.

Targeting TNF-α: The therapeutic potential of certolizumab pegol in the early period of cerebral ischemia reperfusion injury in mice

The neuroinflammatory response triggered by cerebral ischemia-reperfusion injury (CIRI) is characterized by the upsurge of pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-6, which promote leukocyte infiltration and subsequent accumulation in the ischemic zone. This accumulation further intensifies inflammation and aggravates ischemic damage. Certolizumab pegol (CZP), a monoclonal antibody targeting TNF-α, is widely used in treating various inflammatory diseases. This study explored the therapeutic potential of CZP in a mouse model of CIRI, induced by middle cerebral artery occlusion (MCAO), focusing on its influence on the microglial inflammatory response. In vitro analyses revealed that CZP markedly inhibits TNF-α-stimulated inflammation in primary microglia with an EC50 of 1.743 ng/mL. In vivo, MCAO mice treated with CZP (10 μg/mouse, i.p.) for 3 days showed reduced infarct volume, partially improved neurological function, and diminished blood-brain barrierdisruption. Additionally, CZP treatment curtailed microglial activation and the release of pro-inflammatory mediators in the early stages of stroke. It also favorably modulated microglial M1/M2 polarization, rebalanced Th17/Treg cells dynamics, and inhibited Caspase-8-mediated GSDMD cleavage, preventing microglial pyroptosis. Collectively, this study described that the treatment with CZP reversed damaging process caused by CIRI, offering a promising therapeutic strategy for the treatment of ischemic stroke.

A quinolinyl resveratrol derivative alleviates acute ischemic stroke injury by promoting mitophagy for neuroprotection via targeting CK2α'

Ischemic stroke (IS) is a serious threat to human health. The naturally derived small molecule (E)-5-(2-(quinolin-4-yl) ethenyl) benzene-1,3-diol (RV01) is a quinolinyl analog of resveratrol with great potential in the treatment of IS. The aim of this study was to investigate the potential mechanisms and targets for the protective effect of the RV01 on IS. The mouse middle cerebral artery occlusion and reperfusion (MCAO/R) and oxygen-glucose deprivation and reperfusion (OGD/R) models were employed to evaluate the effects of RV01 on ischemic injury and neuroprotection. RV01 was found to significantly increase the survival of SH-SY5Y cells and prevent OGD/R-induced apoptosis in SH-SY5Y cells. Furthermore, RV01 reduced oxidative stress and mitochondrial damage by promoting mitophagy in OGD/R-exposed SH-SY5Y cells. Knockdown of CK2α' abolished the RV01-mediated promotion on mitophagy and alleviation on mitochondrial damage as well as neuronal injury after OGD/R. These results were further confirmed by molecular docking, drug affinity responsive target stability and cellular thermal shift assay analysis. Importantly, in vivo study showed that treatment with the CK2α' inhibitor CX-4945 abolished the RV01-mediated alleviation of cerebral infarct volume, brain edema, cerebral blood flow and neurological deficit in MCAO/R mice. These data suggest that RV01 effectively reduces damage caused by acute ischemic stroke by promoting mitophagy through its interaction with CK2α'. These findings offer valuable insights into the underlying mechanisms through which RV01 exerts its therapeutic effects on IS.

Exploring the intricacies of calcium dysregulation in ischemic stroke: Insights into neuronal cell death and therapeutic strategies

Calcium ion (Ca2+) dysregulation is one of the main causes of neuronal cell death and brain damage after cerebral ischemia. During ischemic stroke, the ability of neurons to maintain Ca2+ homeostasis is compromised. Ca2+ regulates various functions of the nervous system, including neuronal activity and adenosine triphosphate (ATP) production. Disruptions in Ca2+ homeostasis can trigger a cascade of events, including activation of the unfolded protein response (UPR) pathway, which is associated with endoplasmic reticulum (ER) stress and mitochondrial dysfunction. This response occurs when the cell is unable to manage protein folding within the ER due to various stressors, such as a high influx of Ca2+. Consequently, the UPR is initiated to restore ER function and alleviate stress, but prolonged activation can lead to mitochondrial dysfunction and, ultimately, cell death. Hence, precise regulation of Ca2+ within the cell is mandatory. The ER and mitochondria are two such organelles that maintain intracellular Ca2+ homeostasis through various calcium-operating channels, including ryanodine receptors (RyRs), inositol trisphosphate receptors (IP3Rs), sarco/endoplasmic reticulum calcium ATPases (SERCAs), the mitochondrial Na+/Ca2+ exchanger (NCLX), the mitochondrial calcium uniporter (MCU) and voltage-dependent anion channels (VDACs). These channels utilize Ca2+ sequestering and release mechanisms to maintain intracellular Ca2+ homeostasis and ensure proper cellular function and survival. The present review critically evaluates the significance of Ca2+ and its physiological role in cerebral ischemia. We have compiled recent findings on calcium's role and emerging treatment strategies, particularly targeting mitochondria and the endoplasmic reticulum, to address Ca2+ overload in cerebral ischemia.

Argon neuroprotection in ischemic stroke and its underlying mechanism

Ischemic stroke (IS), primarily caused by cerebrovascular obstruction, results in severe neurological deficits and has emerged as a leading cause of death and disability worldwide. Recently, there has been increasing exploration of the neuroprotective properties of the inert gas argon. Argon has exhibited impressive neuroprotection in many in vivo and ex vivo experiments without signs of adverse effects, coupled with the advantages of being inexpensive and easily available. However, the efficient administration strategy and underlying mechanisms of neuroprotection by argon in IS are still unclear. This review summarizes current research on the neuroprotective effects of argon in IS with the goal to provide effective guidance for argon application and to elucidate the potential mechanisms of argon neuroprotection. Early and appropriate argon administration at as high a concentration as possible offers favorable neuroprotection in IS. Argon inhalation has been shown to provide some long-term protection benefits. Argon provides the anti-oxidative stress, anti-inflammatory and anti-apoptotic cytoprotective effects mainly around Toll-like receptor 2/4 (TLR2/4), mediated by extracellular signal-regulated kinase 1/2 (ERK1/2), nuclear factor (erythroid-derived 2)-like 2 (Nrf2), nuclear factor kappa-B (NF-ĸB) and B-cell leukemia/lymphoma 2 (Bcl-2). Therefore, argon holds significant promise as a novel clinical neuroprotective gas agent for ischemic stroke after further researches to identify the optimal application strategy and elucidate the underlying mechanism.

Nanomaterial-Based Strategies for Attenuating T-Cell-Mediated Immunodepression in Stroke Patients: Advancing Research Perspectives

This review article discusses the potential of nanomaterials in targeted therapy and immunomodulation for stroke-induced immunosuppression. Although nanomaterials have been extensively studied in various biomedical applications, their specific use in studying and addressing immunosuppression after stroke remains limited. Stroke-induced neuroinflammation is characterized by T-cell-mediated immunodepression, which leads to increased morbidity and mortality. Key observations related to immunodepression after stroke, including lymphopenia, T-cell dysfunction, regulatory T-cell imbalance, and cytokine dysregulation, are discussed. Nanomaterials, such as liposomes, micelles, polymeric nanoparticles, and dendrimers, offer advantages in the precise delivery of drugs to T cells, enabling enhanced targeting and controlled release of immunomodulatory agents. These nanomaterials have the potential to modulate T-cell function, promote neuroregeneration, and restore immune responses, providing new avenues for stroke treatment. However, challenges related to biocompatibility, stability, scalability, and clinical translation need to be addressed. Future research efforts should focus on comprehensive studies to validate the efficacy and safety of nanomaterial-based interventions targeting T cells in stroke-induced immunosuppression. Collaborative interdisciplinary approaches are necessary to advance the field and translate these innovative strategies into clinical practice, ultimately improving stroke outcomes and patient care.

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.

Ferritinophagy and Ferroptosis in Cerebral Ischemia Reperfusion Injury

Cerebral ischemia-reperfusion injury (CIRI) is the second leading cause of death worldwide, posing a huge risk to human life and health. Therefore, investigating the pathogenesis underlying CIRI and developing effective treatments are essential. Ferroptosis is an iron-dependent mode of cell death, which is caused by disorders in iron metabolism and lipid peroxidation. Previous studies demonstrated that ferroptosis is also a form of autophagic cell death, and nuclear receptor coactivator 4(NCOA4) mediated ferritinophagy was found to regulate ferroptosis by interfering with iron metabolism. Ferritinophagy and ferroptosis are important pathogenic mechanisms in CIRI. This review mainly summarizes the link and regulation between ferritinophagy and ferroptosis and further discusses their mechanisms in CIRI. In addition, the potential treatment methods targeting ferritinophagy and ferroptosis for CIRI are presented, providing new ideas for the prevention and treatment of clinical CIRI in the future.

Genetically Determined Plasma Hepatocyte Growth Factor Levels Are Associated With the Risk and Prognosis of Ischemic Stroke

BACKGROUND

Observational studies suggest that hepatocyte growth factor (HGF) is associated with the risk and prognosis of ischemic stroke, but the causality of these associations remains unclear. Therefore, we conducted Mendelian randomization (MR) analyses to explore the associations of genetically determined plasma HGF levels with the risk and prognosis of ischemic stroke.

METHODS

A total of 13 single-nucleotide polymorphisms associated with plasma HGF were selected as genetic instruments based on the data from a genome-wide association study with 21 758 European participants. Summary data about the risk of ischemic stroke were obtained from the MEGASTROKE (Multiancestry Genome-Wide Association Study of Stroke) Consortium with 34 217 ischemic stroke cases and 406 111 controls of European ancestry, and summary data about the prognosis of ischemic stroke were obtained from the GISCOME study (Genetics of Ischaemic Stroke Functional Outcome) with 6165 European patients with ischemic stroke. We conducted an inverse-variance weighted Mendelian randomization analysis followed by a series of sensitivity analyses to evaluate the associations of genetically determined plasma HGF with the risk and prognosis of ischemic stroke.

RESULTS

The primary analyses showed that genetically determined high HGF was associated with an increased risk of ischemic stroke (odds ratio per SD increase, 1.11 [95% CI, 1.04-1.19]; P=1.10×10-3) and poor prognosis of ischemic stroke (odds ratio per SD increase, 2.43 [95% CI, 1.76-3.52]; P=6.35×10-8). In the secondary analysis, genetically determined plasma HGF was associated with a high risk of large atherosclerotic stroke (odds ratio per SD increase, 1.39 [95% CI, 1.18-1.63]; P=5.08×10-5) but not small vessel stroke and cardioembolic stroke. Mendelian randomization-Egger regression showed no directional pleiotropy for all associations, and the sensitivity analyses with different Mendelian randomization methods further confirmed these findings.

CONCLUSIONS

We found positive associations of genetically determined plasma HGF with the risk and prognosis of ischemic stroke, suggesting that HGF might be implicated in the occurrence and development of ischemic stroke.

Echinacoside ameliorates post-stroke depression by activating BDNF signaling through modulation of Nrf2 acetylation

BACKGROUND

Post-stroke depression (PSD) affects approximately one-third of stroke survivors, leading to adverse outcomes in rehabilitation, reduced quality of life, and increased mortality rates. Despite these implications, the underlying causes of PSD remain unclear, posing challenges for prevention and treatment. Echinacoside (ECH), a natural compound with known neuroprotective and antidepressant properties, holds significant therapeutic potential for PSD. However, the precise mechanism of its action remains unknown.

PURPOSE

To unravel the specific mechanism through which ECH alleviates PSD by exploring the intricate interplay between ECH and Nrf2, as well as its impact on the BDNF/TrkB signaling axis.

STUDY DESIGN AND METHODS

A rat PSD model was established though middle cerebral artery occlusion coupled with chronic unpredictable mild stress, followed by ECH treatment. The rats' depressive state was evaluated using the sucrose preference test and force swimming test. Brain damage was assessed through TTC staining, Nissl staining, and TUNEL assay. The multifaceted mechanism of ECH in PSD was investigated using immunofluorescence, immunohistochemistry, RT-qPCR, dual-luciferase assay, and western blotting. Additionally, the interaction between ECH and Nrf2 was explored through molecular docking and microscale thermophoresis.

RESULTS

Our findings unveiled a novel facet of ECH action, demonstrating its unique ability to upregulate Nrf2 through acetylation within the hippocampus of PSD-affected rats (p < 0.05). Moreover, ECH showcased its distinctive potential by enhancing BDNF transcriptional activity, activating the BDNF/TrkB signaling axis, and orchestrating a comprehensive response against oxidative stress and apoptosis, thereby alleviating PSD symptoms in rats (p < 0.05).

CONCLUSIONS

This study not only provides insights into the pivotal role of Nrf2 in mediating the BDNF/TrkB axis activation by ECH but also highlights the novelty of ECH's mechanism in addressing PSD. The elucidation of these unique aspects positions ECH as a groundbreaking candidate for further exploration and development in the realm of PSD intervention.

In vivo protective effects of 6‑gingerol in cerebral ischemia involve preservation of antioxidant defenses and activation of anti‑apoptotic pathways

Stroke is an important medical problem in developing countries, characterized by a sudden disruption of blood supply to the brain, either through occlusion or hemorrhage. It is a major cause of neurological impairment, resulting in high medical costs. The present study examined the effect of 6-gingerol on morphological changes, antioxidant defenses, and the anti-apoptotic factors p38 mitogen-activated protein kinase (MAPK) and mitofusin (Mfn)2, in a rat model of focal cerebral ischemia. A total of 60 healthy male Wistar rats were randomly allocated into six groups: Control, right middle cerebral artery occlusion (Rt.MCAO) + vehicle, Rt.MCAO + piracetam, and Rt.MCAO + 6-Gin 5, 10 and 20 mg/kg BW groups. The results indicated that 6-gingerol treatment for a duration of 7 days reverses morphological alterations, enhances catalase and glutathione peroxidase activities, reduces Bax, caspase-3 and MAPK expression, and increases Bcl-xL and Mfn2 expression in the cortex and hippocampus. In conclusion, 6-gingerol demonstrated significant in vivo effectiveness in mitigating pathological changes induced by cerebral ischemia. This beneficial effect is attributed, at least in part, to preservation of antioxidant defenses and activation of anti-apoptotic pathways.

GSK-126 Attenuates Cell Apoptosis in Ischemic Brain Injury by Modulating the EZH2-H3K27me3-Bcl2l1 Axis

Whether epigenetic modifications participate in the cell apoptosis after ischemic stroke remains unclear. Histone 3 tri-methylation at lysine 27 (H3K27me3) is a histone modification that leads to gene silencing and is involved in the pathogenesis of ischemic stroke. Since the expression of many antiapoptotic genes is inhibited in the ischemic brains, here we aimed to offer an epigenetic solution to cell apoptosis after stroke by reversing H3K27me3 levels after ischemia. GSK-126, a specific inhibitor of enhancer of zeste homolog 2 (EZH2), significantly decreased H3K27me3 levels and inhibited middle cerebral artery occlusion (MCAO) induced and oxygen glucose deprivation (OGD) induced cell apoptosis. Moreover, GSK-126 attenuated the apoptosis caused by oxidative stress, excitotoxicity, and excessive inflammatory responses in vitro. The role of H3K27me3 in regulating of the expression of the antiapoptotic molecule B cell lymphoma-2 like 1 (Bcl2l1) explained the antiapoptotic effect of GSK-126. In conclusion, we found that GSK-126 could effectively protect brain cells from apoptosis after cerebral ischemia, and this role of GSK-126 is closely related to an axis that regulates Bcl2l1 expression, beginning with the regulation of EZH2-dependent H3K27me3 modification.

Cytokine profiling in senescent and reactive astrocytes: A systematic review

Astrocytes play an important role in neuroinflammation by producing proinflammatory molecules. In response to various stressful stimuli, astrocytes can become senescent or reactive, both are present in age-associated cognitive impairment and other neurodegenerative diseases, and contribute to neuroinflammation. However, there are no studies that compare the cytokines secreted by these types of astrocytes in the brain during aging. Hence, we aimed to broaden the picture of the secretory profiles and to differentiate the variability between them. Therefore, a systematic review was conducted following the guidelines of the "Reporting Items for Systematic Review and Meta-Analyses". Only three studies that met the inclusion terms evaluated age-related cytokine secretion, however, no evaluation of senescence or gliosis was performed. Consequently, to increase the spectrum of the review, studies where those phenotypes were induced and cytokines determined were included. Although some cytokines were common for gliosis and senescence, some interesting differences were also found. The dissimilarities in cytokines secretion between these phenotypes could be studied in the future as potential markers.

Peripheral inflammatory response in people after acute ischaemic stroke and isolated spontaneous cervical artery dissection

The systemic inflammatory response following acute ischaemic stroke remains incompletely understood. We characterised the circulating inflammatory profile in 173 acute ischaemic stroke patients by measuring 65 cytokines and chemokines in plasma. Participants were grouped based on their inflammatory response, determined by high-sensitivity C-reactive protein levels in the acute phase. We compared stroke patients' profiles with 42 people experiencing spontaneous cervical artery dissection without stroke. Furthermore, variations in cytokine levels among stroke aetiologies were analysed. Follow-up samples were collected in a subgroup of ischaemic stroke patients at three and twelve months. Ischaemic stroke patients had elevated plasma levels of HGF and SDF-1α, and lower IL-4 levels, compared to spontaneous cervical artery dissection patients without stroke. Aetiology-subgroup analysis revealed reduced levels of nine cytokines/chemokines (HGF, SDF-1α, IL-2R, CD30, TNF-RII, IL-16, MIF, APRIL, SCF), and elevated levels of IL-4 and MIP-1β, in spontaneous cervical artery dissection (with or without ischaemic stroke as levels were comparable between both groups) compared to other aetiologies. The majority of cytokine/chemokine levels remained stable across the study period. Our research indicates that stroke due to large artery atherosclerosis, cardioembolism, and small vessel occlusion triggers a stronger inflammatory response than spontaneous cervical artery dissection.

Role of histone deacetylases and sirtuins in the ischaemic stroke: a protocol for a systematic review and meta-analysis of animal studies

BACKGROUND

Stroke is a major cause of global mortality and disability. Currently, the treatment of acute ischaemic stroke through reperfusion has posed several challenges, raising the need for complementary options to protect the ischaemic penumbra. Recent investigations have indicated that certain epigenetic factors, specifically, histone deacetylases (HDACs) and sirtuins, can be promising for ischaemic stroke therapy, with recent studies suggesting that inhibitors of HDACs or sirtuins may provide neuronal protection after ischaemic stroke. However, the impact of specific HDAC/sirtuin isoforms on the survival of neuronal cells following stroke is still uncertain. This study aims to provide a comprehensive overview of the function of HDACs and their modulators in the treatment of acute ischaemic stroke.

METHODS

This systematic review and meta-analysis will encompass animal intervention studies that explore the efficacy of modulation of HDACs and sirtuins in the acute phase of ischaemic stroke. The review will be reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Electronic searches will be conducted in PubMed, Web of Science and Scopus, with subsequent screening by independent reviewers based on the established eligibility criteria. Methodological quality will be evaluated using the SYRCLE risk of bias tool. The primary outcomes will be infarct volume and functional response, with the secondary outcomes established a priori. Data pertaining to infarct volume will be used for random-effects meta-analysis. Additionally, a descriptive summary will be conducted for the functional response and secondary outcomes.

DISCUSSION

No systematic review and meta-analysis on the treatment of ischaemic stroke through HDAC modulation has been conducted to date. A comprehensive analysis of the available literature on the relevant preclinical investigations can yield invaluable insights in discerning the most effective trials and in further standardisation of preclinical studies.

SYSTEMATIC REVIEW REGISTRATION

This systematic review has been recorded in the International Prospective Register of Systematic Reviews (PROSPERO), with the assigned reference number: CRD42023381420.

Seasonal variability of lesions distribution in acute ischemic stroke: A retrospective study

Seasonal variability could have an impact on the incidence and outcome of stroke. However, little is known about the correlation between seasonal variability and location of acute cerebral infarction. This study aimed to explore the relationship between onset season and the lesions distribution of acute ischemic stroke (AIS). We retrospectively analysis data from 1488 AIS patients admitted to the Second Hospital of Tianjin Medical University from 2018 to 2022. All subjects completed head magnetic resonance imaging examination (MRI) and were divided into four groups according to the onset seasons. The lesions distribution of AIS was evaluated for anterior/posterior/double circulation infarction (DCI), unilateral/bilateral infarctions, and single/multiple cerebral infarctions based on MRI. Logistic regression models were employed to assess the association of season with lesions distribution of AIS. Subgroup analysis was performed in different stroke subtypes. Of 1488 patients, 387 (26.0%) AIS occurred in spring, 425 (28.6%) in summer, 331 (22.2%) in autumn and 345 (23.2%) in winter. Multivariate logistic regression demonstrated that the winter group had 2.15 times (95% CI:1.44-3.21) risk of multiple infarctions, 2.69 times (95% CI:1.80-4.02) of bilateral infarctions and 1.54 times (95% CI:1.05-2.26) of DCI compared with summer group, respectively. Subgroup analysis showed an increased risk of multiple (p < 0.01) or bilateral infarctions (p < 0.01) in small-artery occlusion (SAO) subtype, and higher risk of bilateral infarctions (p < 0.01) or DCI (p < 0.05) in large artery atherosclerosis (LAA) subtype during winter. No significant associations of season with lesions distribution in cardioembolism subtype. Our study highlighted a prominent seasonal variability in the lesions distribution of AIS, particularly in LAA and SAO subtypes. The findings could help to formulating meteorological risk warning strategies for different subtypes.

A study on the mechanism of Beclin-1 m6A modification mediated by catalpol in protection against neuronal injury and autophagy following cerebral ischemia

OBJECTIVE

Catalpol (CAT) has various pharmacological activities and plays a protective role in cerebral ischemia. It has been reported that CAT played a protective role in cerebral ischemia by upregulaing NRF1 expression. Bioinformatics analysis reveals that NRF1 can be used as a transcription factor to bind to the histone acetyltransferase KAT2A. However, the role of KAT2A in cerebral ischemia remains to be studied. Therefore, we aimed to investigate the role of CAT in cerebral ischemia and its related mechanism.

METHODS

In vitro, a cell model of oxygen and glucose deprivation/reperfusion (OGD/R) was constructed, followed by evaluation of neuronal injury and the expression of METTL3, Beclin-1, NRF1, and KAT2A. In vivo, a MCAO rat model was prepared by means of focal cerebral ischemia, followed by assessment of neurological deficit and brain injury in MCAO rats. Neuronal autophagy was evaluated by observation of autophagosomes in neurons or brain tissues by TEM and detection of the expression of LC3 and p62.

RESULTS

In vivo, CAT reduced the neurological function deficit and infarct volume, inhibited neuronal apoptosis in the cerebral cortex, and significantly improved neuronal injury and excessive autophagy in MCAO rats. In vitro, CAT restored OGD/R-inhibited cell viability, inhibited cell apoptosis, LDH release, and neuronal autophagy. Mechanistically, CAT upregulated NRF1, NRF1 activated METTL3 via KAT2A transcription, and METTL3 inhibited Beclin-1 via m6A modification.

CONCLUSION

CAT activated the NRF1/KAT2A/METTL3 axis and downregulated Beclin-1 expression, thus relieving neuronal injury and excessive autophagy after cerebral ischemia.

NADPH Oxidases in Neurodegenerative Disorders: Mechanisms and Therapeutic Opportunities

SIGNIFICANCE

The NADPH oxidase (NOX) enzyme family, located in the central nervous system (CNS), is recognized as a source of reactive oxygen species (ROS) in the brain. Despite its importance in cellular processes, excessive ROS generation leads to cell death and is involved in the pathogenesis of neurodegenerative disorders.

RECENT ADVANCES

NOX enzymes contribute to the development of neurodegenerative diseases, such as Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and stroke, highlighting their potential as targets for future therapeutic development. This review will discuss NOX's contribution and therapeutic targeting potential in neurodegenerative diseases, focusing on PD, AD, ALS, and Stroke.

CRITICAL ISSUES

Homeostatic and physiological levels of ROS are crucial for regulating several processes, such as development, memory, neuronal signaling, and vascular homeostasis. However, NOX-mediated excessive ROS generation is deeply involved in the damage of DNA, proteins, and lipids, leading to cell death in the pathogenesis of a wide range of diseases, namely neurodegenerative diseases.

FUTURE DIRECTIONS

It is essential to understand the role of NOX homologs in neurodegenerative disorders and the pathological mechanisms undergoing neurodegeneration mediated by increased levels of ROS. This further knowledge will allow the development of new specific NOX inhibitors and their application for neurodegenerative disease therapeutics.

Revealing the pharmacological mechanisms of nao-an dropping pill in preventing and treating ischemic stroke via the PI3K/Akt/eNOS and Nrf2/HO-1 pathways

Nao-an Dropping Pill (NADP) is a Chinese patent medicine which commonly used in clinic for ischemic stroke (IS). However, the material basis and mechanism of its prevention or treatment of IS are unclear, then we carried out this study. 52 incoming blood components were resolved by UHPLC-MS/MS from rat serum, including 45 prototype components. The potential active prototype components hydroxysafflor yellow A, ginsenoside F1, quercetin, ferulic acid and caffeic acid screened by network pharmacology showed strongly binding ability with PIK3CA, AKT1, NOS3, NFE2L2 and HMOX1 by molecular docking. In vitro oxygen-glucose deprivation/reperfusion (OGD/R) experimental results showed that NADP protected HA1800 cells from OGD/R-induced apoptosis by affecting the release of LDH, production of NO, and content of SOD and MDA. Meanwhile, NADP could improve behavioral of middle cerebral artery occlusion/reperfusion (MCAO/R) rats, reduce ischemic area of cerebral cortex, decrease brain water and glutamate (Glu) content, and improve oxidative stress response. Immunohistochemical results showed that NADP significantly regulated the expression of PI3K, Akt, p-Akt, eNOS, p-eNOS, Nrf2 and HO-1 in cerebral ischemic tissues. The results suggested that NADP protects brain tissues and ameliorates oxidative stress damage to brain tissues from IS by regulating PI3K/Akt/eNOS and Nrf2/HO-1 signaling pathways.

Bibliometric analysis of the gut microbiota and stroke from 2002 to 2022

Stroke is the fifth leading cause of death worldwide, and the functional status of the gut plays a key role in patients' prognosis. Recent publications have explored the gut association with stroke, but few articles have been published that specifically address a comprehensive bibliometric analysis of the gut microbiota and its association with stroke. To address this gap, we used bibliometric methods to examine the landscape of research concerning the gut and stroke over approximately two decades, utilizing the Web of Science Core Collection (WoSCC). On November 1, 2022, a search was conducted for English-language articles published between 2002 and 2022, with only including original articles. Visual and statistical analyses were performed using CiteSpace, VOSviewer, and Bibliometrix 4.1.0 Package. After screening relevant articles, the results revealed that the number of articles published in this field has progressively increased during the last two decades. In particular, the total number of publications rapidly increased year by year from 2014. Among them, China ranked first in the world with a total of 227 publications. Authorship analysis highlighted Wang Z as the most prolific author, with 18 publications and an H-index of 14, highlighting significant contributions to this field. Meanwhile, the Southern Medical University of China was identified as the most productive institution. Moreover, analysis of keywords revealed that 'cerebral ischemia', 'intestinal microbiota', 'gut microbiota', and 'trimethylamine N-oxide' were popular topics searched, and research on the relationship between stroke and the gut continues to be a research hotspot. In summary, this study presents an overview of the progress and emerging trends in research on the relationship between stroke and gut health over the past two decades, providing a valuable resource for researchers aiming to understand the current state of the field and identify potential directions for future studies.

Pharmacodynamics and mechanism of Erigeron breviscapus granules in the treatment of ischemic stroke in mice by regulating sphingolipid metabolism based on metabolomics

AIM

Erigeron breviscapus (Vant.) Hand.-Mazz. (EB) granules is the extract preparation of EB, with clear curative effect and unclear mechanism. This study intends to systematically explore the specific mechanism of EB granules in the treatment of IS from the metabolic perspective.

METHODS

The model of transient middle cerebral artery occlusion (tMCAO) in mice was established by the suture-occluded method. The therapeutic effect of EB granules on tMCAO mice was evaluated by behavioral evaluation, brain water content determination, 2,3,5-triphenyltetrazolium chloride (TTC) staining, hematoxylin-eosin (HE) staining, and levels of lactate dehydrogenase (LDH) and neuron specific enolase (NSE) in serum. In order to screen differential metabolites, non-targeted metabolomics technology was used to detect the metabolites in serum before and after administration. Univariate statistics, multivariate statistics and bioinformatics were used to analyze the changes of metabolites in serum of tMCAO mice. The possible related mechanism of EB granules in treating IS was screened by pathway enrichment analysis, and the preliminary verification was carried out at animal level by enzyme linked immunosorbent assay (ELISA) and western blot (WB).

RESULTS

EB granules could significantly improve behavior of tMCAO mice, reduce brain water content and cerebral infarction volume, improve morphology of brain tissue, reduce the levels of LDH and NSE in serum. A total of 232 differential metabolites were screened, which were mainly enriched in many biological processes such as sphingolipid metabolism. The differential metabolite S1P and its receptors S1PR1 and S1PR2 in sphingolipid metabolism were verified. The results showed that the level of S1P in brain tissue increased and the protein expression of S1PR1 decreased significantly after modeling, and reversed after administration, but there was no significant difference in the protein expression of S1PR2.

CONCLUSION

The therapeutic effects of EB granules may be related to affecting sphingolipid metabolism through regulating S1P/S1PR1.

FGF17 protects cerebral ischemia reperfusion-induced blood-brain barrier disruption via FGF receptor 3-mediated PI3K/AKT signaling pathway

Maintaining blood-brain barrier (BBB) integrity is critical components of therapeutic approach for ischemic stroke. Fibroblast growth factor 17 (FGF17), a member of FGF8 superfamily, exhibits the strongest expression throughout the wall of all major arteries during development. However, its molecular action and potential protective role on brain endothelial cells after stroke remains unclear. Here, we observed reduced levels of FGF17 in the serum of patients with ischemic stroke, as well as in the brains of mice subjected to middle cerebral artery occlusion (MCAO) injury and oxygen-glucose deprivation/reoxygenation (OGD/R)-induced brain microvascular endothelial cells (bEnd.3) cells. Moreover, treatment with exogenous recombinant human FGF17 (rhFGF17) decreased infarct volume, improved neurological deficits, reduced Evans Blue leakage and upregulated the expression of tight junctions in MCAO-injured mice. Meanwhile, rhFGF17 increased cell viability, enhanced trans-endothelial electrical resistance, reduced sodium fluorescein leakage, and alleviated reactive oxygen species (ROS) generation in OGD/R-induced bEnd.3 cells. Mechanistically, the treatment with rhFGF17 resulted in nuclear factor erythroid 2-related factor 2 (Nrf2) nuclear accumulation and upregulation of heme oxygenase-1 (HO-1) expression. Additionally, based on in-vivo and in-vitro research, rhFGF17 exerted protective effects against ischemia/reperfusion (I/R) -induced BBB disruption and endothelial cell apoptosis through the activation of the FGF receptor 3/PI3K/AKT signaling pathway. Overall, our findings indicated that FGF17 may hold promise as a novel therapeutic strategy for ischemic stroke patients.

Comprehensive Management of Stroke: From Mechanisms to Therapeutic Approaches

Acute ischemic stroke (AIS) is a challenging disease, which needs urgent comprehensive management. Endovascular thrombectomy (EVT), alone or combined with iv thrombolysis, is currently the most effective therapy for patients with acute ischemic stroke (AIS). However, only a limited number of patients are eligible for this time-sensitive treatment. Even though there is still significant room for improvement in the management of this group of patients, up until now there have been no alternative therapies approved for use in clinical practice. However, there is still hope, as clinical research with novel emerging therapies is now generating promising results. These drugs happen to stop or palliate some of the underlying molecular mechanisms involved in cerebral ischemia and secondary brain damage. The aim of this review is to provide a deep understanding of these mechanisms and the pathogenesis of AIS. Later, we will discuss the potential therapies that have already demonstrated, in preclinical or clinical studies, to improve the outcomes of patients with AIS.

Insight into the pathophysiological advances and molecular mechanisms underlying cerebral stroke: current status

Molecular pathways involved in cerebral stroke are diverse. The major pathophysiological events that are observed in stroke comprises of excitotoxicity, oxidative stress, mitochondrial damage, endoplasmic reticulum stress, cellular acidosis, blood-brain barrier disruption, neuronal swelling and neuronal network mutilation. Various biomolecules are involved in these pathways and several major proteins are upregulated and/or suppressed following stroke. Different types of receptors, ion channels and transporters are activated. Fluctuations in levels of various ions and neurotransmitters have been observed. Cells involved in immune responses and various mediators involved in neuro-inflammation get upregulated progressing the pathogenesis of the disease. Despite of enormity of the problem, there is not a single therapy that can limit infarction and neurological disability due to stroke. This is because of poor understanding of the complex interplay between these pathophysiological processes. This review focuses upon the past to present research on pathophysiological events that are involved in stroke and various factors that are leading to neuronal death following cerebral stroke. This will pave a way to researchers for developing new potent therapeutics that can aid in the treatment of cerebral stroke.

DCPIB Attenuates Ischemia-Reperfusion Injury by Regulating Microglial M1/M2 Polarization and Oxidative Stress

The inflammatory response plays an indispensable role in ischemia-reperfusion injury, the most significant of which is the inflammatory response caused by microglial polarization. Anti-inflammatory therapy is also an important remedial measure after failed vascular reconstruction. Maintaining the internal homeostasis of the brain is a crucial measure for suppressing the inflammatory response. The mechanism underlying the relationship between DCPIB, a selective blocker of volume-regulated anion channels (VRAC), and inflammation induced by cerebral ischemia-reperfusion injury is currently unclear. The purpose of this study was to investigate the relationship between DCPIB and microglial M1/M2 polarization-mediated inflammation after cerebral ischemia-reperfusion injury. C57BL/6 mice were subjected to transient middle cerebral artery occlusion (tMCAO). DCPIB was administered by a lateral ventricular injection within 5 min after reperfusion. Behavioral assessments were conducted at 1, 3, and 7 days after tMCAO/R. Pathological injuries were evaluated using TTC assay, HE and Nissl staining, brain water content measurement, and immunofluorescence staining. The levels of inflammatory cytokines were analyzed using qPCR and ELISA. Additionally, the phenotypic variations of microglia were examined using immunofluorescence staining. In mouse tMCAO/R model, DCPIB administration markably reduced mortality, improved behavioral performance, and alleviated pathological injury. DCPIB treatment significantly inhibited the inflammatory response, promoted the conversion of M1 microglia to M2 microglia via the MAPK signaling pathway, and ultimately protected neurons from the microglia-mediated inflammatory response. In addition, DCPIB inhibited oxidative stress induced by cerebral ischemia-reperfusion injury. In conclusion, DCPIB attenuates cerebral ischemia-reperfusion injury by regulating microglial M1/M2 polarization and oxidative stress.

Outcome of Pulmonary Embolism with and without Ischemic Stroke

Background: Ischemic stroke is the second, and pulmonary embolism (PE) is the third most common cardiovascular cause of death after myocardial infarction. Data regarding risk factors for ischemic stroke in patients with acute PE are limited. Methods: Patients were selected by screening the German nationwide in-patient sample for PE (ICD-code I26) and were stratified by ischemic stroke (ICD code I63) and compared. Results: The nationwide in-patient sample comprised 346,586 hospitalized PE patients (53.3% females) in Germany from 2011 to 2014; among these, 6704 (1.9%) patients had additionally an ischemic stroke. PE patients with ischemic stroke had a higher in-hospital mortality rate than those without (28.9% vs. 14.5%, p < 0.001). Ischemic stroke was independently associated with in-hospital death (OR 2.424, 95%CI 2.278-2.579, p < 0.001). Deep venous thrombosis and/or thrombophlebitis (DVT) combined with heart septal defect (OR 24.714 [95%CI 20.693-29.517], p < 0.001) as well as atrial fibrillation/flutter (OR 2.060 [95%CI 1.943-2.183], p < 0.001) were independent risk factors for stroke in PE patients. Systemic thrombolysis was associated with a better survival in PE patients with ischemic thrombolysis who underwent cardio-pulmonary resuscitation (CPR, OR 0.55 [95%CI 0.36-0.84], p = 0.006). Conclusions: Ischemic stroke did negatively affect the survival of PE. Combination of DVT and heart septal defect and atrial fibrillation/flutter were strong and independent risk factors for ischemic stroke in PE patients. In PE patients with ischemic stroke, who had to underwent CPR, systemic thrombolysis was associated with improved survival.

Astrocyte-Derived Extracellular Vesicles for Ischemic Stroke: Therapeutic Potential and Prospective

Stroke is a leading cause of death and disability in the world. Astrocytes are special glial cells within the central nervous system and play important roles in mediating neuroprotection and repair processes during stroke. Extracellular vesicles (EVs) are lipid bilayer particles released from cells that facilitate intercellular communication in stroke by delivering proteins, lipids, and RNA to target cells. Recently, accumulating evidence suggested that astrocyte-derived EVs (ADEVs) are actively involved in mediating numerous biological processes including neuroprotection and neurorepair in stroke and they are realized as an excellent therapeutic approach for treating stroke. In this review we systematically summarize the up-to-date research on ADEVs in stroke, and prospects for its potential as a novel therapeutic target for stroke. We also provide an overview of the effects and functions of ADEVs on stroke recovery, which may lead to developing clinically relevant therapies for stroke.

Fabrication of Shape Memory Polymer Endovascular Thrombectomy Device for Treating Ischemic Stroke

Stroke is the second result for death and ischemic stroke constitutes most of all stroke cases. Ischemic stroke takes place when blood clot or embolus blocks cerebral vessel and interrupts blood flow, which often leads to brain damage, permanent disability, or death. There is a 4.5-h (golden hour) treatment window to restore blood flow prior to permanent neurological impairment results. Current stroke treatments consist mechanical system or thrombolytic drug therapy to disrupt or dissolve thrombus. Promising method for stroke treatment is mechanical retrieving of thrombi employing device deployed endovascularly. Advent of smart materials has led to research fabrication of several minimally invasive endovascular devices that take advantage of new materials capabilities. One of these capabilities is shape memory, is capability of material to store temporary form, then activate to primary shape as subjected to stimuli. Shape memory polymers (SMPs) are employed as good materials for thrombectomy device fabrication. Therefore, current review presents thrombectomy device development and fabrication with SMPs. Design, performance, limitations, and in vitro or in vivo clinical results of SMP-based thrombectomy devices are identified. Review also sheds light on SMP's future outlook and recommendations for thrombectomy device application, opening a new era for advanced materials in materials science.

Intermittent fasting along with hydroalcoholic extract of Centella-asiatica ameliorates sub-acute hypoxia-induced ischemic stroke in adult zebrafish

Reduced blood flow (hypoxia) to the brain is thought to be the main cause of strokes because it deprives the brain of oxygen and nutrients. An increasing amount of evidence indicates that the Centella-Asiatica (HA-CA) hydroalcoholic extract has a variety of pharmacological benefits, such as antioxidant activity, neuroprotection, anti-inflammatory qualities, and angiogenesis promotion. Intermittent fasting (IF) has neurological benefits such as anti-inflammatory properties, neuroprotective effects, and the ability to enhance neuroplasticity. The current study evaluates the combined effect of IF (for 1, 6, and 12 days) along with HA-CA (daily up to 12 days) in adult zebrafish subjected to hypoxia every 5 min for 12 days followed by behavioral (novel tank and open-field tank test), biochemical (SOD, GSH-Px, and LPO), inflammatory (IL-10, IL-1β, and TNF-α), mitochondrial enzyme activities (Complex-I, II, and IV), signaling molecules (AMPK, MAPK, GSK-3β, Nrf2), and imaging/staining (H&E, TTC, and TEM) analysis. Results show that sub-acute hypoxia promotes the behavioral alterations, and production of radical species and alters the oxidative stress status in brain tissues of zebrafish, along with mitochondrial dysfunction, neuroinflammation, and alteration of signaling molecules. Nevertheless, HA-CA along with IF significantly ameliorates these defects in adult zebrafish as compared to their effects alone. Further, imaging analysis significantly provided evidence of infarct damage along with neuronal and mitochondrial damage which was significantly ameliorated by IF and HA-CA. The use of IF and HA-CA has been proven to enhance the physiological effects of hypoxia in all dimensions.

A Neutrophil Hijacking Nanoplatform Reprograming NETosis for Targeted Microglia Polarizing Mediated Ischemic Stroke Treatment

Precise and efficient regulation of microglia is vital for ischemic stroke therapy and prognosis. The infiltration of neutrophils into the brain provides opportunities for regulatory drugs across the blood-brain barrier, while hindered by neutrophil extracellular traps (NETs) and targeted delivery of intracerebral drugs to microglia. This study reports an efficient neutrophil hijacking nanoplatform (referred to as APTS) for targeted A151 (a telomerase repeat sequence) delivery to microglia without the generation of NETs. In the middle cerebral artery occlusion (MCAO) mouse model, the delivery efficiency to ischemic stroke tissues increases by fourfold. APTS dramatically reduces the formation of NETs by 2.2-fold via reprogramming NETosis to apoptosis in neutrophils via a reactive oxygen species scavenging-mediated citrullinated histone 3 inhibition pathway. Noteworthy, A151 within neutrophils is repackaged into apoptotic bodies following the death pattern reprogramming, which, when engulfed by microglia, polarizes microglia to an anti-inflammatory M2 phenotype. After four times treatment, the cerebral infarction area in the APTS group decreases by 5.1-fold. Thus, APTS provides a feasible, efficient, and practical drug delivery approach for reshaping the immune microenvironment and treating brain disorders in the central nervous system.

Effect of Cyclosporin H on ischemic injury and neutrophil infiltration in cerebral infarct model of rats via PET imaging

BACKGROUND

Brain ischemia-reperfusion injury is a complex process, and neuroinflammation is an important secondary contributing pathological event. Neutrophils play major roles in ischemic neuroinflammation. Once activated, neutrophils express formyl peptide receptors (FPRs), which are special receptors of a class of chemoattractants and may be potential targets to regulate the activity of neutrophils and control cerebral ischemic injury. This study was aimed to explore the ameliorating effect of Cyclosporin H (CsH), a potent FPR antagonist, on brain ischemic injury by inhibiting the activation and migration of neutrophils, and improving cerebral blood flow.

METHODS

We employed a middle cerebral artery occlusion (MCAO) Model on rats and performed behavioral, morphological, and microPET imaging assays to investigate the potential restoring efficacy of CsH on cerebral ischemic damages. Peptide N-cinnamoyl-F-(D)L-F-(D)L-F (cFLFLF), an antagonist to the neutrophil FPR with a high binding affinity, was used for imaging neutrophil distribution.

RESULTS

We found that CsH had similar effect with edaravone on improving the neurobehavioral deficient symptoms after cerebral ischemia-reperfusion, and treatment with CsH also alleviated ischemic cerebral infarction. Compared with the MCAO Model group, [18F]FDG uptake ratios of the CsH and edaravone treatment groups were significantly higher. The CsH-treated groups also showed significant increases in [18F]FDG uptake at 144 h when compared with that of 24 h. This result indicates that like edaravone, treatment with both doses of CsH promoted the recovery of blood supply after cerebral ischemic event. Moreover, MCAO-induced cerebral ischemia significantly increased the radiouptake of [68Ga]Ga-cFLFLF at 72 h after ischemia-reperfusion operation. Compared with MCAO Model group, radiouptake values of [68Ga]-cFLFLF in both doses of CsH and edaravone groups were all decreased significantly. These results showed that both doses of CsH resulted in a similar therapeutic effect with edaravone on inhibiting neutrophil infiltration in cerebral infarction.

CONCLUSION

Potent FPR antagonist CsH is promisingly beneficial in attenuating neuroinflammation and improving neurobehavioral function against cerebral infarction. Therefore, FPR may become a novel target for regulating neuroinflammation and improving prognosis for ischemic cerebrovascular disorders.

Melatonin alleviates ischemic stroke by inhibiting ferroptosis through the CYP1B1/ACSL4 pathway

This study utilized middle cerebral artery occlusion (MCAO) mouse models and HT-22 cell oxygen and glucose deprivation/reoxygenation (OGD/R) models to investigate the therapeutic effects of melatonin on ischemic brain injury. In the experiments, MCAO mice were treated with 5 and 10 mg/kg doses of melatonin, and H-T22 cells underwent OGD/R treatment and were administered different concentrations of melatonin. The results showed that melatonin significantly reduced ischemic brain area, neural damage, cerebral edema, and neuronal apoptosis in MCAO mice. In the HT-22 cell model, melatonin also improved cell proliferation ability, reduced apoptosis, and ROS production. Further mechanistic studies found that melatonin exerts protective effects by inhibiting ferroptosis, an iron-dependent form of regulated cell death, through regulation of the ACSL4/CYP1B1 pathway. In MCAO mice, melatonin decreased lipid peroxidation, ROS production, and ACSL4 protein expression. Overexpression of CYP1B1 increased ACSL4 ubiquitination and degradation, thereby increasing cell tolerance to ferroptosis, reducing ACSL4 protein levels, and decreasing ROS production. CYP1B1 knockdown obtained opposite results. The CYP1B1 metabolite 20-HETE induces expression of the E3 ubiquitin ligase FBXO10 by activating PKC signaling, which promotes ACSL4 degradation. In the OGD/R cell model, inhibition of CYP1B1 expression reversed the therapeutic effects of melatonin. In summary, this study demonstrates that melatonin protects the brain from ischemic injury by inhibiting ferroptosis through regulation of the ACSL4/CYP1B1 pathway, providing evidence for new therapeutic targets for ischemic brain injury.

Intranasal Delivery of Mitochondria Attenuates Brain Injury by AMPK and SIRT1/PGC-1α Pathways in a Murine Model of Photothrombotic Stroke

Ischemic stroke is one of the major causes of morbidity and mortality worldwide. Mitochondria play a vital role in the pathological processes of cerebral ischemic injury, but its transplantation and underlying mechanisms remain unclear. In the present study, we examined the effects of mitochondrial therapy on the modulation of AMPK and SIRT1/PGC-1α signaling pathway, oxidative stress, and NLRP3 inflammasome activation after photothrombotic ischemic stroke (pt-MCAO). The adult male mice were subjected to the pt-MCAO in which the proximal-middle cerebral artery was exposed with a 532-nm laser beam for 4 min by retro-orbital injection of a photosensitive dye (Rose Bengal: 15 mg/kg) before the laser light exposure and isolated mitochondria (100 μg protein) were administered intranasally at 30 min, 24 h, and 48 h following post-stroke. After 72 h, mice were tested for neurobehavioral outcomes and euthanized for infarct volume, brain edema, and molecular analysis. First, we found that mitochondria therapy significantly decreased brain infarct volume and brain edema, improved neurological dysfunction, attenuated ischemic stroke-induced oxidative stress, and neuroinflammation. Second, mitochondria treatment inhibited NLRP3 inflammasome activation. Finally, mitochondria therapy accelerated p-AMPKα(Thr172) and PGC-1α expression and resorted SIRT1 protein expression levels in pt-MCAO mice. In conclusion, our results demonstrate that mitochondria therapy exerts neuroprotective effects by inhibiting oxidative damage and inflammation, mainly dependent on the heightening activation of the AMPK and SIRT1/PGC-1α signaling pathway. Thus, intranasal delivery of mitochondria might be considered a new therapeutic strategy for ischemic stroke treatment.

Mastoparan M promotes functional recovery in stroke mice by activating autophagy and inhibiting ferroptosis

Neuronal ferroptosis and autophagy are crucial in the pathogenesis of cerebral ischemia-reperfusion injury (CIRI). Mastoparan M (Mast-M), extracted from the crude venom of Vespa magnifica (Smith), comprises 14 amino acid residues. Previous studies suggested that Mast-M reduces neuronal damage following global CIRI, but its protective mechanisms remain unclear. The present study examined the effect of Mast-M on middle cerebral artery occlusion/reperfusion (MCAO/R) induced neurological deficits using Grip, Rotarod, Longa test, and TTC staining, followed by treating the mice for three days with Mast-M (20, 40, and 80 μg/kg, subcutaneously). The results demonstrate that Mast-M promotes functional recovery in mice post-ischemic stroke, evidenced by improved neurological impairment, reduced infarct volume and neuronal damage. Meanwhile, the level of iron (Fe2+) and malonyldialdehyde was decreased in the ischemic hemisphere of MCAO/R mice at 24 hours or 48 hours by Mast-M (80 μg/kg) treatment, while the expression of NRF2, x-CT, GPX4, and LC3B protein was increased. Furthermore, these findings were validated in three models-oxygen-glucose deprivation/ reoxygenation, H2O2-induced peroxidation, and erastin-induced ferroptosis-in hippocampal neuron HT22 cells or primary neurons. These data suggested that Mast-M activates autophagy as well as inhibits ferroptosis. Finally, autophagy inhibitors were introduced to determine the relationship between the autophagy and ferroptosis, indicating that Mast-M alleviates ferroptosis by activating autophagy. Taken together, this study described that Mast-M alleviates cerebral infarction, neurologic impairment, and neuronal damage by activating autophagy and inhibiting ferroptosis, presenting a potential therapeutic approach for CIRI.

High glutamine increases stroke risk by inducing the endothelial-to-mesenchymal transition in moyamoya disease

At present, there is limited research on the mechanisms underlying moyamoya disease (MMD). Herein, we aimed to determine the role of glutamine in MMD pathogenesis, and 360 adult patients were prospectively enrolled. Human brain microvascular endothelial cells (HBMECs) were subjected to Integrin Subunit Beta 4 (ITGB4) overexpression or knockdown and atorvastatin. We assessed factors associated with various signaling pathways in the context of the endothelial-to-mesenchymal transition (EndMT), and the expression level of related proteins was validated in the superficial temporal arteries of patients. We found glutamine levels were positively associated with a greater risk of stroke (OR = 1.599, p = 0.022). After treatment with glutamine, HBMECs exhibited enhanced proliferation, migration, and EndMT, all reversed by ITGB4 knockdown. In ITGB4-transfected HBMECs, the MAPK-ERK-TGF-β/BMP pathway was activated, with Smad4 knockdown reversing the EndMT. Furthermore, atorvastatin suppressed the EndMT by inhibiting Smad1/5 phosphorylation and promoting Smad4 ubiquitination in ITGB4-transfected HBMECs. We also found the protein level of ITGB4 was upregulated in the superficial temporal arteries of patients with MMD. In conclusion, our study suggests that glutamine may be an independent risk factor for hemorrhage or infarction in patients with MMD and targeting ITGB4 could potentially be therapeutic approaches for MMD.

Drugs/agents for the treatment of ischemic stroke: Advances and perspectives

Ischemic stroke (IS) poses a significant threat to global human health and life. In recent decades, we have witnessed unprecedented progresses against IS, including thrombolysis, thrombectomy, and a few medicines that can assist in reopening the blocked brain vessels or serve as standalone treatments for patients who are not eligible for thrombolysis/thrombectomy therapies. However, the narrow time windows of thrombolysis/thrombectomy, coupled with the risk of hemorrhagic transformation, as well as the lack of highly effective and safe medications, continue to present big challenges in the acute treatment and long-term recovery of IS. In the past 3 years, several excellent articles have reviewed pathophysiology of IS and therapeutic medicines for the treatment of IS based on the pathophysiology. Regretfully, there is no comprehensive overview to summarize all categories of anti-IS drugs/agents designed and synthesized based on molecular mechanisms of IS pathophysiology. From medicinal chemistry view of point, this article reviews a multitude of anti-IS drugs/agents, including small molecule compounds, natural products, peptides, and others, which have been developed based on the molecular mechanism of IS pathophysiology, such as excitotoxicity, oxidative/nitrosative stresses, cell death pathways, and neuroinflammation, and so forth. In addition, several emerging medicines and strategies, including nanomedicines, stem cell therapy and noncoding RNAs, which recently appeared for the treatment of IS, are shortly introduced. Finally, the perspectives on the associated challenges and future directions of anti-IS drugs/agents are briefly provided to move the field forward.

Transsynaptic degeneration of ventral horn motor neurons exists but plays a minor role in lower motor system dysfunction in acute ischemic rats

BACKGROUND

As a leading cause of mortality and long-term disability, acute ischemic stroke can produce far-reaching pathophysiological consequences. Accumulating evidence has demonstrated abnormalities in the lower motor system following stroke, while the existence of Transsynaptic degeneration of contralateral spinal cord ventral horn (VH) neurons is still debated.

METHODS

Using a rat model of acute ischemic stroke, we analyzed spinal cord VH neuron counts contralaterally and ipsilaterally after stroke with immunofluorescence staining. Furthermore, we estimated the overall lower motor unit abnormalities after stroke by simultaneously measuring the modified neurological severity score (mNSS), compound muscle action potential (CMAP) amplitude, repetitive nerve stimulation (RNS), spinal cord VH neuron counts, and the corresponding muscle fiber morphology. The activation status of microglia and extracellular signal-regulated kinase 1/2 (ERK 1/2) in the spinal cord VH was also assessed.

RESULTS

At 7 days after stroke, the contralateral CMAP amplitudes declined to a nadir indicating lower motor function damage, and significant muscle disuse atrophy was observed on the same side; meanwhile, the VH neurons remained intact. At 14 days after focal stroke, lower motor function recovered with alleviated muscle disuse atrophy, while transsynaptic degeneration occurred on the contralateral side with elevated activation of ERK 1/2, along with the occurrence of neurogenic muscle atrophy. No apparent decrement of CMAP amplitude was observed with RNS during the whole experimental process.

CONCLUSIONS

This study offered an overview of changes in the lower motor system in experimental ischemic rats. We demonstrated that transsynaptic degeneration of contralateral VH neurons occurred when lower motor function significantly recovered, which indicated the minor role of transsynaptic degeneration in lower motor dysfunction during the acute and subacute phases of focal ischemic stroke.

Comparative neuroprotective effects of royal jelly and its unique compound 10-hydroxy-2-decenoic acid on ischemia-induced inflammatory, apoptotic, epigenetic and genotoxic changes in a rat model of ischemic stroke

OBJECTIVES

This study aimed to compare the efficacy of royal jelly (RJ) and its major fatty acid 10-hydroxy-2-decenoic acid (10-HDA) on ischemic stroke-related pathologies using histological and molecular approaches.

METHODS

Male rats were subjected to middle cerebral artery occlusion (MCAo) to induce ischemic stroke and were supplemented daily with either vehicle (control group), RJ or 10-HDA for 7 days starting on the day of surgery. On the eighth day, rats were sacrificed and brain tissue and blood samples were obtained to analyze brain infarct volume, DNA damage as well as apoptotic, inflammatory and epigenetic parameters.

RESULTS

Both RJ and 10-HDA supplementation significantly reduced brain infarction and decreased weight loss when compared to control animals. These effects were associated with reduced levels of active caspase-3 and PARP-1 and increased levels of acetyl-histone H3 and H4. Although both RJ and 10-HDA treatments significantly increased acetyl-histone H3 levels, the effect of RJ was more potent than that of 10-HDA. RJ and 10-HDA supplementation also alleviated DNA damage by significantly reducing tail length, tail intensity and tail moment in brain tissue and peripheral lymphocytes, except for the RJ treatment which tended to reduce tail moment in lymphocytes without statistical significance.

CONCLUSIONS

Our findings suggest that neuroprotective effects of RJ in experimental stroke can mostly be attributed to 10-HDA.

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.

Rhoa/ROCK, mTOR and Secretome-Based Treatments for Ischemic Stroke: New Perspectives

Ischemic stroke triggers a complex cascade of cellular and molecular events leading to neuronal damage and tissue injury. This review explores the potential therapeutic avenues targeting cellular signaling pathways implicated in stroke pathophysiology. Specifically, it focuses on the articles that highlight the roles of RhoA/ROCK and mTOR signaling pathways in ischemic brain injury and their therapeutic implications. The RhoA/ROCK pathway modulates various cellular processes, including cytoskeletal dynamics and inflammation, while mTOR signaling regulates cell growth, proliferation, and autophagy. Preclinical studies have demonstrated the neuroprotective effects of targeting these pathways in stroke models, offering insights into potential treatment strategies. However, challenges such as off-target effects and the need for tissue-specific targeting remain. Furthermore, emerging evidence suggests the therapeutic potential of MSC secretome in stroke treatment, highlighting the importance of exploring alternative approaches. Future research directions include elucidating the precise mechanisms of action, optimizing treatment protocols, and translating preclinical findings into clinical practice for improved stroke outcomes.

Ischemic stroke pathophysiology: A bibliometric and visualization analysis from 1990 to 2022

Background

Pathophysiology plays a significant role in the scientific study of ischemic stroke, and has attracted increasing interest from researchers in the field. However, a comprehensive bibliometric analysis is lacking in this field. The purpose of this study is to identify the current research status and hotspots of ischemic stroke pathophysiology from a bibliometric perspective.

Methods

The Web of Science Core Collection database was searched for articles published from 1990 to 2022. CiteSpace, VOSviewer, and R package "bibliometrix" software were used to analyze countries/regions, institutions, journals, authors, papers, and keywords to predict the latest trends in ischemic stroke pathophysiology research.

Results

This analysis collected 7578 records of ischemic stroke pathophysiology. China and America emerged as the leading countries in this field, with Harvard University being the most active institution. Among journals and authors in this field, journal Stroke and author Gregory YH Lip published the most papers, while Nature Medicine was the journal with the highest citation per article. Keywords and co-citation clusters were closely related to "central nervous system", "mechanisms", "biochemistry & molecular biology" and "radiology, nuclear medicine & medical imaging", while other related fields, such as peripheral organs damage induced by the central nervous system and rehabilitation after ischemic stroke, require further research efforts.

Conclusion

This is the first bibliometric study that comprehensively mapped out the knowledge structure and development trends of ischemic stroke pathophysiology in recent 32 years, which may provide a reference for scholars to explore ischemic stroke pathophysiology.

Myricetin Oligomer Triggers Multi-Receptor Mediated Penetration and Autophagic Restoration of Blood-Brain Barrier for Ischemic Stroke Treatment

Restoration of blood-brain barrier (BBB) dysfunction, which drives worse outcomes of ischemic stroke, is a potential target for therapeutic opportunities, whereas a sealed BBB blocks the therapeutics entrance into the brain, making the BBB protection strategy paradoxical. Post ischemic stroke, hypoxia/hypoglycemia provokes the up-regulation of transmembrane glucose transporters and iron transporters due to multiple metabolic disorders, especially in brain endothelial cells. Herein, we develop a myricetin oligomer-derived nanostructure doped with Ce to bypass the BBB which is cointermediated by glucose transporters and iron transporters such as glucose transporters 1 (GLUT1), sodium/glucose cotransporters 1 (SGLT1), and transferrin(Tf) reporter (TfR). Moreover, it exhibits BBB restoration capacity by regulating the expression of tight junctions (TJs) through the activation of protective autophagy. The myricetin oligomers scaffold not only acts as targeting moiety but is the prominent active entity that inherits all diverse pharmacological activities of myricetin. The suppression of oxidative damage, M1 microglia activation, and inflammatory factors makes it a multitasking nanoagent with a single component as the scaffold, targeting domain and curative components.

Th17 Cells and IL-17A in Ischemic Stroke

The neurological injury and repair mechanisms after ischemic stroke are complex. The inflammatory response is present throughout stroke onset and functional recovery, in which CD4 + T helper(Th) cells play a non-negligible role. Th17 cells, differentiated from CD4 + Th cells, are regulated by various extracellular signals, transcription factors, RNA, and post-translational modifications. Th17 cells specifically produce interleukin-17A(IL-17A), which has been reported to have pro-inflammatory effects in many studies. Recently, experimental researches showed that Th17 cells and IL-17A play an important role in promoting stroke pathogenesis (atherosclerosis), inducing secondary damage after stroke, and regulating post-stroke repair. This makes Th17 and IL-17A a possible target for the treatment of stroke. In this paper, we review the mechanism of action of Th17 cells and IL-17A in ischemic stroke and the progress of research on targeted therapy.