Inflammation-Mediated Angiogenesis in Ischemic Stroke

Telencephalic stab wound injury induces regenerative angiogenesis and neurogenesis in zebrafish: unveiling the role of vascular endothelial growth factor signaling and microglia

JOURNAL/nrgr/04.03/01300535-202510000-00025/figure1/v/2024-11-26T163120Z/r/image-tiff After brain damage, regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals, suggesting a close link between these processes. However, the mechanisms by which these processes interact are not well understood. In this work, we aimed to study the correlation between angiogenesis and neurogenesis after a telencephalic stab wound injury. To this end, we used zebrafish as a relevant model of neuroplasticity and brain repair mechanisms. First, using the Tg( fli1:EGFP × mpeg1.1:mCherry ) zebrafish line, which enables visualization of blood vessels and microglia respectively, we analyzed regenerative angiogenesis from 1 to 21 days post-lesion. In parallel, we monitored brain cell proliferation in neurogenic niches localized in the ventricular zone by using immunohistochemistry. We found that after brain damage, the blood vessel area and width as well as expression of the fli1 transgene and vascular endothelial growth factor ( vegfaa and vegfbb ) were increased. At the same time, neural stem cell proliferation was also increased, peaking between 3 and 5 days post-lesion in a manner similar to angiogenesis, along with the recruitment of microglia. Then, through pharmacological manipulation by injecting an anti-angiogenic drug (Tivozanib) or Vegf at the lesion site, we demonstrated that blocking or activating Vegf signaling modulated both angiogenic and neurogenic processes, as well as microglial recruitment. Finally, we showed that inhibition of microglia by clodronate-containing liposome injection or dexamethasone treatment impairs regenerative neurogenesis, as previously described, as well as injury-induced angiogenesis. In conclusion, we have described regenerative angiogenesis in zebrafish for the first time and have highlighted the role of inflammation in this process. In addition, we have shown that both angiogenesis and neurogenesis are involved in brain repair and that microglia and inflammation-dependent mechanisms activated by Vegf signaling are important contributors to these processes. This study paves the way for a better understanding of the effect of Vegf on microglia and for studies aimed at promoting angiogenesis to improve brain plasticity after brain injury.

Environmental enrichment: a neurostimulatory approach to aging and ischemic stroke recovery and rehabilitation

Environmental enrichment (EE) represents a robust experimental framework exploring the intricate interplay between genes and the environment in shaping brain development and function. EE is recognized as a non-invasive intervention, easily translatable to elderly human cohorts, and extrapolated from research on animal aging models. Age is the most important risk factor for ischemic stroke. Research indicates that EE, characterized by increased sensory, cognitive, and social stimulation, leads to structural changes in the brain, such as enhanced dendritic complexity and synaptic density, particularly in the hippocampus and cortex. Tailored EE interventions for elderly stroke survivors include cognitively stimulating activities and participation in social groups. These interventions enhance cognitive function and support recovery by promoting neural repair. Additionally, EE helps to mitigate sensory deficits commonly observed in older adults, ultimately improving mental performance and quality of life. EE has shown promise in preventing relapse, enhancing attention, reducing anxiety, forestalling age-related DNA methylation alterations, and amplifying neurogenesis through heightened neural progenitor cell (NPC) populations. Aligning preclinical studies with clinical trials can enhance neurorehabilitation conditions for stroke patients, thereby optimizing the environments in which they recover. This can be achieved through the concerted efforts of multidisciplinary teams working collaboratively. This review explores how EE specifically impacts the aging brain and ischemic stroke, a major age-related neurological disorder with global health implications. The potential of enviro-mimetics and relevant clinical studies on EE's effects on ischemic stroke survivors are discussed. This review enhances our understanding of the effects of EE on aging and ischemic stroke, motivating further research aimed at refining strategies for stroke management and recovery.

The Neuroprotective Mechanisms of Kaempferol in Experimental Ischemic Stroke: A Preclinical Systematic Review

Ischemic stroke represents a critical global health challenge, resulting in significant mortality and disability worldwide, yet there are limited effective treatment options currently available. While the intricate molecular pathways underlying the onset and progression of ischemic stroke are multifaceted, relying on a single therapeutic approach is unlikely to yield effective treatment for this complex disease. Therefore, it is crucial to explore efficient strategies that employ multifaceted targeting and address the multifarious pathological processes to overcome the challenges associated with ischemic brain injury. In recent times, natural plant-derived compounds have garnered significant interest as promising neuroprotective agents for the management of neurological conditions, including ischemic stroke. This study investigates the possible neuroprotective properties of kaempferol, a naturally occurring flavonoid compound, in mitigating the detrimental consequences of cerebral ischemic events. The findings from the reviewed preclinical studies suggest that kaempferol exhibits significant neuroprotective potential as a multifaceted therapeutic agent for ischemic stroke. Its efficacy stems from a combination of antioxidant, anti-inflammatory, and anti-apoptotic properties, which collectively mitigate ischemic stroke-induced brain injury. While these results are promising, clinical studies are essential to validate kaempferol's therapeutic viability for ischemic stroke patients.

Paeoniflorin Attenuates Limb Ischemia by Promoting Angiogenesis Through ERα/ROCK-2 Pathway

Background: Peripheral artery disease (PAD) is a high-risk vascular condition, and vascular remodeling has become a promising therapeutic approach. Paeoniflorin (PF) is the main bioactive compound in the roots of Paeonia lactiflora Pall, which is commonly used to treat a range of cardiovascular disorders. However, the mechanisms underlying the ameliorating effects of PF on PAD remain unclear. Therefore, the purpose of this study was to explore the therapeutic efficiency of PF on PAD and determine its mechanisms. Methods: The blood flow of mice was detected with a laser Doppler dot scanning imaging system. HE staining was used to observe the morphological changes of ischemic muscle. The changes in the serologic indexes were detected with an automatic biochemical assay, and the capillary density of ischemic gastrocnemius was detected with a Lectin immunofluorescence assay. The expression of angiogenesis-related proteins in ischemic gastrocnemius was detected with Western blotting, and the proportion of macrophages and neutrophils in total cells was detected with flow cytometry. Results: PF significantly increased blood flow, capillary density and protein expressions of vascular endothelial growth factor A (VEGFA), matrix metalloproteinase 2 (MMP2), matrix metalloproteinase 2 (MMP9), and estrogen receptor α (ERα) in mouse ischemic tissue in a PAD model. PF enhances the migration of endothelial cells and promotes the formation of tubular structures, involving the ERα/ROCK2 signaling pathway. Furthermore, PF was found to promote the phenotypic transformation of macrophages and alleviated grave inflammatory responses during vascular remodeling. Conclusions: We determined that PF as a potent compound in promoting angiogenesis and mitigating inflammatory responses during revascularization.

Key mechanisms of angiogenesis in the infarct core: association of macrophage infiltration with venogenesis

Angiogenesis in the ischemic penumbra compensates for microcirculatory dysfunction and promotes neuronal plasticity after stroke. However, the current understanding may be highly biased because the contribution of veins to angiogenesis has been overlooked. This study revealed that the remodeling processes of veins differ from those of arteries after ischemia. Ligation of the right jugular vein increased the infarct volume, decreased cerebral blood flow and impaired long-term functional restoration after stroke. RNA-seq analysis revealed significant upregulation of the expression of genes associated with angiogenesis in the infarct core during the recovery period. By using gelatin ink-alkaline phosphatase-oil red O (GIAO) staining, we found that venogenesis, the process of creating new veins, was the predominant angiogenic event in the infarct core. Macrophage infiltration and transformation are closely associated with venogenesis in the infarct core. However, depletion of macrophages in the circulation by clodronate liposomes in the acute phase inhibited the proliferation of endothelial progenitor cells and decreased the vascular density in the infarct core. This study demonstrated that dynamic vein remodeling is crucial for cerebral ischemic damage and subsequent neuronal restoration. Angiogenesis occurs in the infarct core during the recovery period, promotes the absorption of necrotic tissue and facilitates functional recovery after stroke.

Loss of white matter tracts and persistent microglial activation in the chronic phase of ischemic stroke in female rats and the effect of miR-20a-3p treatment

Our previous studies showed that intravenous injections of the small non-coding RNA mir-20a-3p is neuroprotective for stroke in the acute phase and attenuates long-term cognitive impairment in middle-aged female rats. In this study, we evaluated postmortem brain pathology at 100+d after stroke in a set of behaviorally characterized animals. This included Sham (no stroke) controls or stroke animals that received either mir20a-3p at 4h, 24h and 70d iv post stroke (MCAo+mir20a-3p) or a scrambled oligo (MCAo+Scr). Brain volumetric features were analyzed with T2 weighted and Diffusion Tensor magnetic resonance imaging (MRI) followed by histological analysis. Principal component analysis of Fractional Anisotropy (FA)-diffusion tensor MRI measures showed that MCAo+Scr and MCAo+mir20a-3p groups differed significantly in the volume of white matter but not gray matter. Weil myelin-stained sections confirmed decreased volume of the corpus callosum, internal capsule and the anterior commissure in the ischemic hemisphere of MCAo+Scr animals compared to the non-ischemic hemisphere, while sham and MCAo+Mir-20a-3p showed no hemispheric asymmetries. The MCAo+Scr group also exhibited asymmetry in hemisphere and lateral ventricle volumes, with ventricular enlargement in the ischemic hemisphere as compared to the non-ischemic hemisphere. The numbers of microglia were significantly elevated in white matter tracts in the MCAo+Scr group, with a trend towards increased myelin phagocytic microglia in these tracts. Regression analysis indicated that performance on an episodic memory test (novel object recognition test; NORT) was associated with decreased white matter volume and increased microglial numbers. These data support the hypothesis that stroke-induced cognitive impairment is accompanied by white matter attrition and persistent microglial activation and is consistent with reports that cognitive deterioration resulting from vascular diseases, such as stroke, is associated with secondary neurodegeneration in regions distal from the initial infarction.

Clustered VEGF Nanoparticles in Microporous Annealed Particle (MAP) Hydrogel Accelerates Functional Recovery and Brain Tissue Repair after Stroke

Ischemic stroke, a blockage in the vasculature of the brain that results in insufficient blood flow, is one of the world's leading causes of disability. The cascade of inflammation and cell death that occurs immediately following stroke drives vascular and functional loss that does not fully recover over time, and no FDA-approved therapies exist that stimulate regeneration post-stroke. We have previously developed a hydrogel scaffold that delivered heparin nanoparticles with and without VEGF bound to their surface to promote angiogenesis and reduce inflammation, respectively. However, the inclusion of the naked heparin nanoparticles warranted concern over the development of bleeding complications. Here, we explore how microporous annealed particle (MAP) scaffolds functionalized with VEGF coated heparin nanoparticles can both reduce inflammation and promote angiogenesis - without the inclusion of free heparin nanoparticles. We show that our updated design not only successfully promotes de novo tissue formation, including the development of mature vessels and neurite sprouting, but it also leads to functional improvement in a photothrombotic stroke model. In addition, we find increased astrocyte infiltration into the infarct site correlated with mature vessel formation. This work demonstrates how our biomaterial design can enhance endogenous regeneration post-stroke while eliminating the need for excess heparin.

Local delivery of platelet-derived factors mitigates ischemia and preserves ovarian function through angiogenic modulation: A personalized regenerative strategy for fertility preservation

As the most prominent and ideal modality in female fertility preservation, ovarian tissue cryopreservation, and transplantation often confront the challenge of ischemic damage and follicular loss from avascular transplantation. To surmount this impediment, we engineered a novel platelet-derived factors-encapsulated fibrin hydrogel (PFH), a paradigmatic biomaterial. PFH encapsulates autologous platelet-derived factors, utilizing the physiological blood coagulation cascade for precise local delivery of bioactive molecules. In our study, PFH markedly bolstered the success of avascular ovarian tissue transplantation. Notably, the quantity and quality of follicles were preserved with improved neovascularization, accompanied by decreased DNA damage, increased ovulation, and superior embryonic development rates under a Low-concentration Platelet-rich plasma-derived factors encapsulated fibrin hydrogel (L-PFH) regimen. At a stabilized point of tissue engraftment, gene expression analysis mirrored normal ovarian tissue profiles, underscoring the effectiveness of L-PFH in mitigating the initial ischemic insult. This autologous blood-derived biomaterial, inspired by nature, capitalizes on the blood coagulation cascade, and combines biodegradability, biocompatibility, safety, and cost-effectiveness. The adjustable properties of this biomaterial, even in injectable form, extend its potential applications into the broader realm of personalized regenerative medicine. PFH emerges as a promising strategy to counter ischemic damage in tissue transplantation, signifying a broader therapeutic prospect. (197 words).

A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

JOURNAL/nrgr/04.03/01300535-202502000-00028/figure1/v/2024-05-28T214302Z/r/image-tiff Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI (QK) are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases. However, conventional topical drug delivery often results in a burst release of the drug, leading to transient retention (inefficacy) and undesirable diffusion (toxicity) in vivo. Therefore, a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke. Matrix metalloproteinase-2 (MMP-2) is gradually upregulated after cerebral ischemia. Herein, vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG (TIMP) and customizable peptide amphiphilic (PA) molecules to construct nanofiber hydrogel PA-TIMP-QK. PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro. The results indicated that PA-TIMP-QK promoted neuronal survival, restored local blood circulation, reduced blood-brain barrier permeability, and restored motor function. These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Non-histone lactylation: unveiling its functional significance

Lactylation, a newly discovered protein posttranslational modification (PTM) in 2019, primarily occurs on lysine residues. Lactylation of histones was initially identified, and subsequent studies have increasingly demonstrated its widespread presence on non-histone proteins. Recently, high-throughput proteomics studies have identified a large number of lactylated proteins and sites, revealing their global regulatory role in disease development. Notably, this modification is catalyzed by lactyltransferase and reversed by delactylase, with numerous new enzymes, such as AARS1/2, reported to be involved. Specifically, these studies have revealed how lactylation exerts its influence through alterations in protein spatial conformation, molecular interactions, enzyme activity and subcellular localization. Indeed, lactylation is implicated in various physiological and pathological processes, including tumor development, cardiovascular and cerebrovascular diseases, immune cell activation and psychiatric disorders. This review provides the latest advancements in research on the regulatory roles of non-histone protein lactylation, highlighting its crucial scientific importance for future studies.

Acute Three-Dimensional Hypoxia Regulates Angiogenesis

Hypoxia elicits a multitude of tissue responses depending on the severity and duration of the exposure. While chronic hypoxia is shown to impact development, regeneration, and cancer, the understanding of the threats of acute (i.e., short-term) hypoxia is limited mainly due to its transient nature. Here, a novel gelatin-dextran (Gel-Dex) hydrogel is established that decouples hydrogel formation and oxygen consumption and thus facilitates 3D sprouting from endothelial spheroids and, subsequently, induces hypoxia "on-demand." The Gel-Dex platform rapidly achieves acute moderate hypoxic conditions without compromising its mechanical properties. Acute exposure to hypoxia leads to increased endothelial cell migration and proliferation, promoting the total length and number of vascular sprouts. This work finds that the enhanced angiogenic response is mediated by reactive oxygen species, independently of hypoxia-inducible factors. Reactive oxygen species-dependent matrix metalloproteinases activity mediated angiogenic sprouting is observed following acute hypoxia. Overall, the Gel-Dex hydrogel offers a novel platform to study how "on-demand" acute moderate hypoxia impacts angiogenesis, with broad applicability to the development of novel sensing technologies.

Polymorphism in Genes Encoding HSP40 Family Proteins is Associated with Ischemic Stroke Risk and Brain Infarct Size: A Pilot Study

BACKGROUND

Heat shock proteins (HSPs) play a critical role in the molecular mechanisms of ischemic stroke (IS). A possible role for HSP40 family proteins in atherosclerosis progression has already been revealed; however, to date, molecular genetic studies on the involvement of genes encoding proteins of the HSP40 family in IS have not yet been carried out.

AIM

We sought to determine whether nine single nucleotide polymorphisms (SNPs) in genes encoding HSP40 family proteins (DNAJB1, DNAJB2, DNAJA1, DNAJA2, DNAJA3 and DNAJC7) are associated with the risk and clinical features of IS.

METHODS

Using TaqMan-based polymerase chain reaction (PCR) and the MassArray-4 system, DNA samples of 2551 Russians - 1306 IS patients and 1245 healthy individuals - were genotyped.

RESULTS

SNP rs2034598 DNAJA2 decreased the risk of IS exclusively in male patients (odds ratio = 0.81, 95% confidence interval 0.78-0.98, p = 0.028); rs7189628 DNAJA2 increased the brain infarct size (p = 0.04); and rs6500605 DNAJA3 lowered the age of onset of IS (p = 0.03). SNPs rs10448231 DNAJA1, rs7189628 DNAJA2, rs4926222 DNAJB1 and rs2034598 DNAJA2 were involved in the strongest epistatic interactions linked to IS; SNP rs10448231 DNAJA1 is characterised by the most essential mono-effect (2.96% of IS entropy); all of the top SNP-SNP interaction models included the pairwise combination rs7189628 DNAJA2×rs4926222 DNAJB1, which was found to be a key factor determining susceptibility to IS. In interactions with the studied SNPs, smoking was found to have multidirectional effects (synergism, antagonism or additive effect) and the strongest mono-effect (3.47% of IS entropy), exceeding the mono-effects of rs6500605 DNAJA3, rs10448231 DNAJA1, rs2034598 DNAJA2, rs7189628 DNAJA2 and rs4926222 DNAJB1, involved in the best G×E models and determining 0.03%-0.73% of IS entropy.

CONCLUSIONS

We are the first to discover polymorphisms in genes encoding HSP40 family proteins as a major risk factor for IS and its clinical manifestations. The comprehensive bioinformatics analysis revealed molecular mechanisms, underscoring their significance in the pathogenesis of IS, primarily reflecting the regulation of heat stress, proteostasis and cellular signalling.

Enriched environment enhances angiogenesis in ischemic stroke through SDF-1/CXCR4/AKT/mTOR pathway

Environmental-gene interactions significantly influence various bodily functions. Enriched environment (EE), a non-pharmacological treatment method, enhances angiogenesis in ischemic stroke (IS). However, underlying the role of EE in angiogenesis in aged mice post-IS remain unclear. This study aimed to determine the potential mechanism by which EE mediates angiogenesis in 12-month-old IS mice and oxygen-glucose deprivation/reperfusion (OGD/R)-induced bEnd.3 cells. In vivo, EE treatment alleviated the neurological deficits, enhanced angiogenesis, upregulated SDF-1, VEGFA, and the AKT/mTOR pathway. In addition, exogenous SDF-1 treatment had a protective effect similar to that of EE treatment in aged mice with IS. However, SDF-1 neutralizing antibody, AMD3100 (CXCR4 inhibitor), ARQ092 (AKT inhibitor), and rapamycin (mTOR inhibitor) treatment blocked the neuroprotective effect of EE treatment and inhibited angiogenesis in IS mice. In vitro, exogenous SDF-1 promoted migration of OGD/R-induced bEnd.3 cells and activated the AKT/mTOR pathway. AMD3100, ARQ092, and rapamycin inhibited SDF-1-induced cell migration. Collectively, these findings demonstrate that EE enhances angiogenesis and improves the IS outcomes through SDF-1/CXCR4/AKT/mTOR pathway.

miRNA-6236 Regulation of Postischemic Skeletal Muscle Angiogenesis

BACKGROUND

Peripheral arterial disease affects >200 million people worldwide and is characterized by impaired blood flow to the lower extremities. There are no effective medical treatments available. Using the mouse hind-limb ischemia model and miRNA sequencing, we identified a novel miRNA, miR-6236, whose expression significantly elevated in ischemic mouse limbs compared with nonischemic limbs. The role of miR-6236 in general or in postischemic angiogenesis is not known. Here we describe its role using in vivo and in vitro models of peripheral arterial disease.

METHODS AND RESULTS

In primary mouse and human endothelial cells, we studied the effect of simulated ischemia on miR-6236 expression and assessed its role in cell viability, apoptosis, migration, and tube formation during ischemia. Furthermore, we developed miR-6236 null mice and tested its role in postischemic perfusion recovery using the hind-limb ischemia model. Lastly, using bioinformatics and gene expression analysis, we identified putative angiogenic miR-6236 targets. In vitro simulated ischemia-enhanced miR-6236 expression in mouse and human endothelial cells, whereas its inhibition improved viability, migration, tube formation, and reduced apoptosis. In vivo ischemic mouse skeletal muscle tissue showed higher miR-6236 expression compared with nonischemic muscles. Loss of miR-6236 improved impaired postischemic perfusion recovery and poor angiogenesis associated with streptozotocin-induced diabetes in mice. Six of the 8 miR-6236 predicted angiogenic target mRNAs showed expression consistent with regulation by miR-6236 in ischemic skeletal muscle.

CONCLUSIONS

Our results show for the first time that miR-6236 plays a key role in regulating postischemic perfusion recovery and angiogenesis.

Sevoflurane Postconditioning Protects From an Early Neurological Deficit After Subarachnoid Hemorrhage: Results of a Randomized Laboratory Study in Rats

BACKGROUND

Subarachnoid hemorrhage (SAH) is associated with neurocognitive impairment. Recent data suggest that sevoflurane attenuates edema formation after SAH in rats. However, so far, no information is available about the long-term repair phase, nor if sevoflurane impacts functionality by increasing vascularity. This study tested whether sevoflurane postconditioning would improve long-term neurologic deficit through increased formation of new vessels close to the hemorrhage area.

METHODS

Fifty-three animals were subjected to SAH or sham surgery with or without a 2-hour sevoflurane postconditioning (versus propofol anesthesia). Animal survival, including dropout animals due to death or reaching termination criteria, as well as neurologic deficit, defined by the Garcia score, were assessed 2 hours after recovery until postoperative day 14. On day 14, blood samples and brain tissue were harvested. Vessel density was determined by the number of cluster of differentiation 31 (CD31)-positive vessels, and activated glial cells by glial fibrillary acidic protein (GFAP)-positive astrocytes per field of view.

RESULTS

The survival rate for sham animals was 100%, 69% in the SAH-propofol and 92% in the SAH-sevoflurane groups. According to the log-rank Mantel-Cox test, survival curves were significantly different ( P = .024). The short-term neurologic deficit was higher in SAH-propofol versus SAH-sevoflurane animals 2 hours after recovery and on postoperative day 1 (propofol versus sevoflurane: 14. 6 ± 3.4 vs 15. 9 ± 2.7 points, P = .034, and 16. 2 ± 3.5 vs 17. 8 ± 0.9 points, P = .015). Overall complete recovery from neurologic deficit was observed on day 7 in both SAH groups (18. 0 ± 0.0 vs 18. 0 ± 0.0 points, P = 1.000). Cortical vascular density increased to 80. 6 ± 15.0 vessels per field of view in SAH-propofol animals (vs 71. 4 ± 10.1 in SAH-sevoflurane, P < .001). Activation of glial cells, an indicator of neuroinflammation, was assessed by GFAP-positive astrocytes GFAP per field of view. Hippocampal GFAP-positive cells were 201 ± 68 vs 179 ± 84 cells per field of view in SAH-propofol versus SAH-sevoflurane animals ( P < .001).

CONCLUSIONS

Sevoflurane postconditioning improves survival by 23% (SAH-sevoflurane versus SAH-propofol). The sevoflurane intervention could attenuate the early neurologic deficit, while the long-term outcome was similar across the groups. A higher vascular density close to the SAH area in the propofol group was not associated with improved outcomes.

Microglia-mediated endothelial protection: the role of SHPL-49 in ischemic stroke

It was previously shown that SHPL-49, a glycoside derivative of salidroside formed through structural modification, exhibited neuroprotective effects in a rat cerebral ischemia model of permanent middle cerebral artery occlusion (pMCAO). Additionally, SHPL-49 enhanced the mRNA expression of vascular endothelial growth factor-a (Vegf-a) in macrophages. Microglia, functioning as resident macrophages within the brain, promptly respond to cerebral ischemia and engage in interactions with the cells of the Glial-Vascular Unit to orchestrate nerve injury responses. We postulated that the neuroprotective effects of SHPL-49 were mediated through microglia-dependent amelioration of endothelial dysfunction following cerebral ischemia. The present study demonstrates that SHPL-49 effectively mitigated microglia-dependent endothelial dysfunction in the pMCAO model by upregulating the expression of VEGF and suppressing the release of MMP-9 from microglia. Further MRI analyses confirmed that SHPL-49 significantly reduced nerve and endothelial function when microglia were depleted in the brains of pMCAO rats. The above phenomenon was also confirmed in the in vitro experiment investigating microglia-mediated brain endothelial cell function. Furthermore, we discovered that SHPL-49 activates the VEGFR2/Akt/eNOS pathways in endothelial cells and suppresses the p38 MAPK/MMP-9 pathways in microglia cells, thereby facilitating brain endothelial cell protection. Altogether, we have demonstrated that SHPL-49 effectively ameliorates endothelial dysfunction induced by cerebral ischemia through a microglia-dependent mechanism, thereby providing more valuable insights and references for the clinical evaluation of SHPL-49 injection for ischemic stroke.

Global research trends and prospects on immune-related therapy in ischemic stroke: a bibliometric analysis

Background

Following ischemic stroke, non-neuronal cells within the nervous system play a crucial role in maintaining neurovascular unit functions, regulating metabolic and inflammatory processes of the nervous system. Investigating the functions and regulation of these cells, particularly immune cells, deepens our understanding of the complex mechanisms of neuroinflammation and immune modulation after ischemic stroke and provides new perspectives and methods for immune-related therapy.

Methods

The annual distribution, journals, authors, countries, institutions, and keywords of articles published between 2015 and 2024 were visualized and analyzed using CiteSpace and other bibliometric tools.

Results

A total of 1,089 relevant articles or reviews were included, demonstrating an overall upward trend; The terms "cerebral ischemia," "immune response," "brain ischemia," "cerebral inflammation," "neurovascular unit," and "immune infiltration," etc. are hot keywords in this field.

Conclusion

In recent years, research on immune-related therapy for ischemic stroke has focused on mechanisms of occurrence, protection and repair of the blood-brain barrier (BBB) by non-neuronal cells, and regulation of immunosuppression and inflammation. Among these, reducing BBB disruption to minimize secondary brain damage has become a hotspot. At the same time, the complex roles of immune responses have attracted attention, particularly the balance between regulatory T cells and Th17 cells in regulating neuroinflammation and promoting neurological function recovery, which is crucial to reduce secondary neuronal damage and improve prognosis, potentially establishing a pivotal frontier in this domain of investigation.

Comparative analysis of meningeal transcriptomes in birds: Potential pathways of resilience to repeated impacts

The meninges and associated vasculature (MAV) play a crucial role in maintaining cerebral integrity and homeostasis. Recent advances in transcriptomic analysis have illuminated the significance of the MAV in understanding the complex physiological interactions at the interface between the skull and the brain after exposure to mechanical stress. To investigate how physiological responses may confer resilience against repetitive mechanical stress, we performed the first transcriptomic analysis of avian MAV tissues using the Downy Woodpecker (Dryobates pubescens) and Tufted Titmouse (Baeolophus bicolor) as the comparison species. Our findings reveal divergences in gene expression profiles related to immune response, cellular stress management, and protein translation machinery. The male woodpeckers exhibit a tailored immune modulation strategy that potentially dampens neuroinflammation while preserving protective immunity. Overrepresented genes involved in cellular stress responses suggest enhanced mechanisms for mitigating damage and promoting repair. Additionally, the enrichment of translation-associated pathways hints at increased capacity for protein turnover and cellular remodeling vital for recovery. Our study not only fills a critical gap in avian neurobiology but also lays the groundwork for research in comparative neuroprotection.

Comparing clinical outcomes in patients with type 2 diabetes mellitus after ischaemic stroke: Sodium-glucose cotransporter 2 inhibitors users versus non-users. A propensity score matching National Cohort Study

AIM

This nationwide cohort study evaluated the impact of sodium-glucose co-transporter-2 inhibitors (SGLT2i) on patients with type 2 diabetes mellitus (T2DM) after ischaemic stroke (IS), aiming to compare clinical outcomes between SGLT2i-treated patients and those not receiving SGLT2i.

MATERIALS AND METHODS

Utilizing Taiwan's National Health Insurance Research Database, we identified 707 patients with T2DM treated with SGLT2i and 27 514 patients not treated with SGLT2i after an IS, respectively, from 1 May 2016 to 31 December 2019. Propensity score matching was applied to balance baseline characteristics. The follow-up period extended from the index date (3 months after the index acute IS) until the independent occurrence of the study outcomes, 6 months after discontinuation of the index drug, or the end of the study period (31 December 2020), whichever came first.

RESULTS

After propensity score matching, compared with the non-SGLT2i group (n = 2813), the SGLT2i group (n = 707) exhibited significantly lower recurrent IS rates (3.605% per year vs. 5.897% per year; hazard ratio: 0.55; 95% confidence interval: 0.34-0.88; p = 0.0131) and a significant reduction in all-cause mortality (5.396% per year vs. 7.489% per year; hazard ratio: 0.58; 95% confidence interval: 0.39-0.85; p = 0.0058). No significant differences were observed in the rates of acute myocardial infarction, cardiovascular death, heart failure hospitalization, or lower limb amputation.

CONCLUSIONS

Our findings indicate significantly lower risks of recurrent IS and all-cause mortality among patients with T2DM receiving SGLT2i treatment. Further studies are required to validate these results and investigate the underlying mechanisms behind the observed effects.

The Los Angeles motor scale (LAMS) and ASPECTS score are independently associated with DSA ASITN collateral score

BACKGROUND

Mechanical thrombectomy (MT) is the treatment standard in eligible patients with acute ischemic stroke (AIS) secondary to large vessel occlusions (LVO). Studies have shown that good collateral status is a strong predictor of MT efficacy, thus making collateral status important to quickly assess. The Los Angeles Motor Scale is a clinically validated tool for identifying LVO in the field. The aim of this study is to investigate whether admission LAMS score is also associated with the American Society of Interventional and Therapeutic Neuroradiology (ASITN) collateral score on digital subtraction angiography (DSA).

METHODS

We conducted a retrospective multicenter cohort study of consecutive patients presenting with AIS caused by LVO from 9/1/2017 to 10/1/2023 with diagnostically adequate DSA imaging. Demographic, clinical, and imaging data was collected through manual chart review. Both univariate and multivariate analysis were applied to assess associations. A p-value <0.05 was considered significant.

RESULTS

A total of 308 patients (median age: 68, IQR: 57.5-77) were included in the study. On multivariate logistic regression analysis, we found that lower admission LAMS score (adjusted OR: 0.82, 95% CI: 0.68-0.98, p < 0.05) and higher ASPECTS score (adjusted OR: 1.21, 95% CI: 1.02-1.42, p < 0.05) were independently associated with good DSA ASITN collateral score of 3-4.

CONCLUSIONS

Admission LAMS and ASPECTS score are both independently associated with DSA ASITN collateral score. This demonstrates the capability of LAMS to act as a surrogate marker of CS in the field.

Effect of advanced maternal age on ischemic stroke vulnerability in aged rats: Investigating on blood-brain barrier permeability and gene expression

Background

Advanced maternal age (AMA), commonly defined as pregnancy at or above 35 years old. Based on the evidence, this trend has raised concerns about potential health consequences for mothers, particularly in relation to ischemic stroke. Studies suggest that AMA may be associated with a higher risk of ischemic stroke in women due to physiological changes that impact vascular health and increase cardiovascular risk factors. The aim of this study was to investigate the effect of AMA on the extent of damage after ischemic stroke in aged rats.

Methods

Female rats that gave birth at an old age (10 months) and at a young age (4 months) were subjected to ischemic stroke in old age (20 months) and subsequently compared.We assessed neurological deficits, infarct volume, blood-brain barrier (BBB) permeability, TNF-alpha levels, total oxidant capacity, and gene expressions that play a role in BBB integrity (VEGF, Occludin, and MMP-9) following ischemic stroke.

Results

There were significantly elevated levels of MMP-9 expression and reduced levels of occludin in AMA rats. Additionally, AMA rats had significantly higher levels of TNF-alpha and total oxidant capacity after experiencing an ischemic stroke. AMA rats showed significantly higher brain water content (BBB permeability), infarct volume, and neurological deficits compared to young-aged pregnancies.

Discussion

Complex relationship between pregnancy-related physiological changes, aging, vascular gene expression, and inflammatory factors may play a role in the increased vulnerability observed in older pregnant rats. The similarities between pregnancy-related alterations and aging highlight the influence of advanced maternal age on susceptibility to ischemic stroke.

Integrated Strategies for Targeting Arteriogenesis and Angiogenesis After Stroke

The interdependence between arteriogenesis and angiogenesis is crucial for enhancing perfusion by synchronously improving leptomeningeal collaterals (LMCs) and microvascular networks after stroke. However, current approaches often focus on promoting arteriogenesis and angiogenesis separately, neglecting the potential synergistic benefits of targeting both processes simultaneously. Therefore, it is imperative to consider both arteriogenesis and angiogenesis as integral and complementary strategies for post-stroke revascularization. To gain a deeper understanding of their relationships after stroke and to facilitate the development of targeted revascularization strategies, we compared them based on their timescale, space, and pathophysiology. The temporal differences in the occurrence of arteriogenesis and angiogenesis allow them to restore blood flow at different stages after stroke. The spatial differences in the effects of arteriogenesis and angiogenesis enable them to specifically target the ischemic penumbra and core infarct region. Additionally, the endothelial cell, as the primary effector cell in their pathophysiological processes, is promising target for enhancing both. Therefore, we provide an overview of key signals that regulate endothelium-mediated arteriogenesis and angiogenesis. Finally, we summarize current therapeutic strategies that involve these signals to promote both processes after stroke, with the aim of inspiring future therapeutic advances in revascularization.

The natural compound sinometumine E derived from Corydalis decumbens promotes angiogenesis by regulating HIF-1/ VEGF pathway in vivo and in vitro

The rhizome of Corydalis decumbens is a traditional Chinese medicine commonly utilized in the clinical treatment of acute ischemic stroke. Numerous phytochemical and biological investigations have demonstrated that protoberberine alkaloids from C. decumbens exhibit diverse pharmaceutical activities against various diseases. Sinometumine E (SE), a protoberberine alkaloid isolated from C. decumbens for the first time, is characterized by a complex 6/6/6/6/6/6 hexacyclic skeleton. In the current study, we investigated the protective effects of SE on endothelial cell injury and its angiogenesis effects in zebrafish. The results suggested that SE showed significant anti-ischemic effects on OGD/R-induced HBEC-5i and HUVECs cell ischemia/reperfusion injury model. Furthermore, it promoted angiogenesis in PTK787-induced, MPTP-induced, and atorvastatin-induced vessel injury models of zebrafish, while also suppressing hypoxia-induced locomotor impairment in zebrafish. Transcriptome sequencing analysis provided a sign that SE likely to promotes angiogenesis through the HIF-1/VEGF signaling pathway to exert anti-ischemic effects. Consistently, SE modulated several genes related to HIF-1/VEGF signal pathway, such as hif-1, vegf, vegfr-2, pi3k, erk, akt and plcγ. Molecular docking analysis revealed that VEGFR-2 exhibited high binding affinity with SE, and western blot analysis confirmed that SE treatment enhanced the expression of VEGFR-2. In conclusion, our study profiled the angiogenic activities of SE in vitro and in vivo. The key targets and related pathways involved in anti-ischemic effects of SE, shedding light on the pharmacodynamic components and mechanisms of Corydalis decumbens, and provides valuable insights for identifying effective substances for the treatment of ischemic stroke.

The Transcriptional Landscape of Pericytes in Acute Ischemic Stroke

The current treatment options for ischemic stroke aim to achieve reperfusion but are time critical. Novel therapeutic approaches that can be given beyond the limited time window of 3-4.5 h are still an unmet need to be addressed to improve stroke outcomes. The lack of oxygen and glucose in the area of ischemic injury initiates a pathological cascade leading to blood-brain barrier (BBB) breakdown, inflammation, and neuronal cell death, a process that may be intercepted to limit stroke progression. Pericytes located at the blood/brain interface are one of the first responders to hypoxia in stroke and therefore a potential target cell for early stroke interventions. Using single-cell RNA sequencing in a mouse model of permanent middle cerebral artery occlusion, we investigated the temporal differences in transcriptomic signatures in pericytes at 1, 12, and 24 h after stroke. Our results reveal a stroke-specific subcluster of pericytes that is present at 12 and 24 h and characterized by the upregulation of genes mainly related to cytokine signaling and immune response. This study identifies temporal transcriptional changes in the acute phase of ischemic stroke that reflect the early response of pericytes to the ischemic insult and its secondary consequences and may constitute potential future therapeutic targets.

The Janus face of HIF-1α in ischemic stroke and the possible associated pathways

Stroke is the most devastating disease, causing paralysis and eventually death. Many clinical and experimental trials have been done in search of a new safe and efficient medicine; nevertheless, scientists have yet to discover successful remedies that are also free of adverse effects. This is owing to the variability in intensity, localization, medication routes, and each patient's immune system reaction. HIF-1α represents the modern tool employed to treat stroke diseases due to its functions: downstream genes such as glucose metabolism, angiogenesis, erythropoiesis, and cell survival. Its role can be achieved via two downstream EPO and VEGF strongly related to apoptosis and antioxidant processes. Recently, scientists paid more attention to drugs dealing with the HIF-1 pathway. This review focuses on medicines used for ischemia treatment and their potential HIF-1α pathways. Furthermore, we discussed the interaction between HIF-1α and other biological pathways such as oxidative stress; however, a spotlight has been focused on certain potential signalling contributed to the HIF-1α pathway. HIF-1α is an essential regulator of oxygen balance within cells which affects and controls the expression of thousands of genes related to sustaining homeostasis as oxygen levels fluctuate. HIF-1α's role in ischemic stroke strongly depends on the duration and severity of brain damage after onset. HIF-1α remains difficult to investigate, particularly in ischemic stroke, due to alterations in the acute and chronic phases of the disease, as well as discrepancies between the penumbra and ischemic core. This review emphasizes these contrasts and analyzes the future of this intriguing and demanding field.

NEAT1 inhibits the angiogenic activity of cerebral arterial endothelial cells by inducing the M1 polarization of microglia through the AMPK signaling pathway

BACKGROUND

Enhancing angiogenesis may be an effective strategy to promote functional recovery after ischemic stroke. Inflammation regulates angiogenesis. Microglia are crucial cells that initiate inflammatory responses after various brain injuries. Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) plays a role in regulating brain injury. This study aimed to explore the effects of NEAT1-regulated microglial polarization on the neovascularization capacity of cerebrovascular endothelial cells and the underlying molecular regulatory mechanisms.

METHODS

Mouse cerebral arterial endothelial cells (mCAECs) were co-cultured with BV-2 cells in different groups using a Transwell system. NEAT1 expression levels were measured by fluorescence quantitative reverse transcription PCR. Levels of IL-1β, IL-6, TNF-α, Arg-1, IL-4, and IL-10 were determined using ELISA. Expression levels of CD86 and CD163 were detected by immunofluorescence. The neovascularization capacity of mCAECs was assessed using CCK-8, Transwell, Transwell-matrigel, and tube formation assays. Label-free quantification proteomics was carried out to identify differentially expressed proteins. Protein levels were measured by Western blotting.

RESULTS

NEAT1 overexpression induced M1 polarization in BV-2 cells, whereas NEAT1 knockdown blocked lipopolysaccharide-induced M1 polarization in microglia. NEAT1-overexpressing BV-2 cells suppressed the angiogenic ability of mCAECs, and NEAT1-knocking BV-2 cells promoted the angiogenic ability of mCAECs under lipopolysaccharide treatment. Label-free quantitative proteomic analysis identified 144 upregulated and 131 downregulated proteins that were induced by NEAT1 overexpression. The AMP-activated protein kinase (AMPK) signaling pathway was enriched in the Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed proteins. Further verification showed that NEAT1 inactivated the AMPK signaling pathway. Moreover, the AMPK activator 5-aminoimidazole-4-carboxamide ribonucleotide reversed the effect of NEAT1 on BV-2 polarization and the regulatory effect of NEAT1-overexpressing BV-2 cells on the angiogenic ability of mCAECs.

CONCLUSIONS

NEAT1 inhibits the angiogenic activity of mCAECs by inducing M1 polarization of BV-2 cells through the AMPK signaling pathway. This study further clarified the impact and mechanism of NEAT1 on microglia and the angiogenic ability of cerebrovascular endothelial cells.

Decoding Tumor Angiogenesis for Therapeutic Advancements: Mechanistic Insights

Tumor angiogenesis, the formation of new blood vessels within the tumor microenvironment, is considered a hallmark of cancer progression and represents a crucial target for therapeutic intervention. The tumor microenvironment is characterized by a complex interplay between proangiogenic and antiangiogenic factors, regulating the vascularization necessary for tumor growth and metastasis. The study of angiogenesis involves a spectrum of techniques, spanning from biomarker assessment to advanced imaging modalities. This comprehensive review aims to provide insights into the molecular intricacies, regulatory dynamics, and clinical implications of tumor angiogenesis. By delving into these aspects, we gain a deeper understanding of the processes driving vascularization in tumors, paving the way for the development of novel and effective antiangiogenic therapies in the fight against cancer.

Enhanced angiogenesis in the thalamus induced by a novel TSPO ligand ameliorates cognitive deficits after focal cortical infarction

Neuronal loss in the ipsilateral thalamus after focal cortical infarction participates in post-stroke cognitive deficits, and enhanced angiogenesis in the thalamus is expected to reduce neuronal damage. We hypothesize that novel translocator protein (TSPO) ligand, 2-Cl-MGV-1, can promote angiogenesis, attenuate neuronal loss in the thalamus, and ameliorate post-stroke cognitive deficits. Cortical infarction was induced by distal middle cerebral artery occlusion (dMCAO) in stroke-prone renovascular hypertensive rats. 2-Cl-MGV-1 or dimethyl sulfoxide was administered 24 h after dMCAO and then for 6 or 13 days. Spatial learning and memory were assessed using the Morris water maze. Neuronal loss, TSPO expression, angiogenesis, and intrinsic pathway were determined by immunofluorescence and immunoblotting 7 and 14 days after dMCAO. Cortical infarction caused post-stroke cognitive deficits and secondary neuronal loss with gliosis in the ipsilateral thalamus within 14 days of dMCAO. Increased angiogenesis and elevated expression of vascular TSPO were detected in the ipsilateral thalamus, and treatment with 2-Cl-MGV-1 enhanced angiogenesis by stimulating the PI3K-AKT-mTOR pathway. The effects of 2-Cl-MGV-1 on angiogenesis coincided with reduced neuronal loss in the thalamus and contributed to improvements in post-stroke cognitive deficits. Our findings suggest that 2-Cl-MGV-1 stimulates angiogenesis, ameliorates neuronal loss in the thalamus, and improves post-stroke cognitive deficits.

Resveratrol ameliorates glioblastoma inflammatory response by reducing NLRP3 inflammasome activation through inhibition of the JAK2/STAT3 pathway

OBJECTIVES

The aim of this study was to investigate the anti-tumor effect of resveratrol (RSV) on glioblastoma (GBM) and its specific mechanism in improving the inflammatory response of the tumor microenvironment. The tumor microenvironment of GBM is highly neuroinflammatory, inducing tumor immunosuppression. Therefore, ameliorating the inflammatory response is an important focus for anti-tumor research.

METHODS

The anti-tumor effect of RSV on GBM was demonstrated through in vitro cellular assays, including CCK-8, EdU, PI staining, Transwell, wound healing assay, and flow cytometry. Potential mechanisms of RSV's anti-GBM effects were identified through network pharmacological analysis. In addition, the relationship of RSV with the JAK2/STAT3 signaling pathway and the inflammasome NLRP3 was verified using Western blot.

RESULTS

RSV significantly inhibited cell viability in GBM cell lines LN-229 and U87-MG. Furthermore, it inhibited the proliferation and invasive migration ability of GBM cells, while promoting apoptosis. Network pharmacological analysis revealed a close association between the anti-GBM effects of RSV and the JAK/STAT signaling pathway, as well as inflammatory responses. Western blot analysis confirmed that RSV inhibited the over-activation of the inflammasome NLRP3 through the JAK2/STAT3 signaling pathway. Partial reversal of RSV's inhibition of inflammasome NLRP3 was observed with the addition of the JAK/STAT agonist RO8191.

CONCLUSIONS

In vitro, RSV can exert anti-tumor effects on GBM and improve the inflammatory response in the GBM microenvironment by inhibiting the activation of the JAK2/STAT3 signaling pathway. These findings provide new insights into potential therapeutic targets for GBM.

The role and therapeutic potential of nuclear factor κB (NF-κB) in ischemic stroke

Stroke is a prevalent cerebrovascular condition with a global impact, causing significant rates of illness and death. Despite extensive research, the available treatment options for stroke remain restricted. Hence, it is crucial to gain a deeper understanding of the molecular mechanisms associated with the onset and advancement of stroke in order to establish a theoretical foundation for novel preventive and therapeutic approaches. NF-κB, also known as nuclear factor κB, is a transcription factor responsible for controlling the expression of numerous genes and plays a crucial role in diverse physiological processes. NF-κB is triggered and regulates neuroinflammation and other processes after stroke, promoting the generation of cytokine storms and contributing to the advancement of ischemic stroke (IS). Therefore, NF-κB could potentially play a vital role in stroke by regulating diverse pathophysiological processes. This review provides an overview of the functions of NF-κB in stroke and its governing mechanisms. In addition, our attention is directed towards various potential therapies that aim to inhibit the NF-κB signaling pathway in order to offer valuable insights for the advancement of innovative treatment approaches for stroke.

Understanding mechanistic aspect of the therapeutic role of herbal agents on neuroplasticity in cerebral ischemic-reperfusion injury

ETHNOPHARMACOLOGICAL RELEVANCE

Stroke is one of the leading causes of death and disability. The only FDA-approved therapy for treating stroke is tissue plasminogen activator (tPA), exhibiting a short therapeutic window. Due to this reason, only a small number of patients can be benefitted in this critical period. In addition, the use of endovascular interventions may reverse vessel occlusion more effectively and thus help further improve outcomes in experimental stroke. During recovery of blood flow after ischemia, patients experience cognitive, behavioral, affective, emotional, and electrophysiological changes. Therefore, it became the need for an hour to discover a novel strategy for managing stroke. The drug discovery process has focused on developing herbal medicines with neuroprotective effects via modulating neuroplasticity.

AIM OF THE STUDY

We gather and highlight the most essential traditional understanding of therapeutic plants and their efficacy in cerebral ischemia-reperfusion injury. In addition, we provide a concise summary and explanation of herbal drugs and their role in improving neuroplasticity. We review the pharmacological activity of polyherbal formulations produced from some of the most frequently referenced botanicals for the treatment of cerebral ischemia damage.

MATERIALS AND METHODS

A systematic literature review of bentham, scopus, pubmed, medline, and embase (elsevier) databases was carried out with the help of the keywords like neuroplasticity, herbal drugs, neural progenitor cells, neuroprotection, stem cells. The review was conducted using the above keywords to understand the therapeutic and mechanistic role of herbal neuroprotective agents on neuroplasticity in cerebral ischemic-reperfusion injury.

RESULTS

Neuroplasticity emerged as an alternative to improve recovery and management after cerebral ischemic reperfusion injury. Neuroplasticity is a physiological process throughout one's life in response to any stimuli and environment. Traditional herbal medicines have been established as an adjuvant to stroke therapy since they were used from ancient times and provided promising effects as an adjuvant to experimental stroke. The plants and phytochemicals such as Curcuma longa L., Moringa oliefera Lam, Panax ginseng C.A. Mey., and Rehmannia glutinosa (Gaertn.) DC., etc., have shown promising effects in improving neuroplasticity after experimental stroke. Such effects occur by modulation of various molecular signalling pathways, including PI3K/Akt, BDNF/CREB, JAK/STAT, HIF-1α/VEGF, etc. CONCLUSIONS: Here, we gave a perspective on plant species that have shown neuroprotective effects and can show promising results in promoting neuroplasticity with specific targets after cerebral ischemic reperfusion injury. In this review, we provide the complete detail of studies conducted on the role of herbal drugs in improving neuroplasticity and the signaling pathway involved in the recovery and management of experimental stroke.

Crosstalk between inflammasomes, inflammation, and Nrf2: Implications for gestational diabetes mellitus pathogenesis and therapeutics

The role of inflammasomes in gestational diabetes mellitus (GDM) has emerged as a critical area of research in recent years. Inflammasomes, key components of the innate immune system, are now recognized for their involvement in the pathogenesis of GDM. Activation of inflammasomes in response to various triggers during pregnancy can produce pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and interleukin-18 (IL-18), contributing to systemic inflammation and insulin resistance. This dysregulation not only impacts maternal health but also poses significant risks to fetal development and long-term health outcomes. Understanding the intricate interplay between inflammasomes and GDM holds promise for developing novel therapeutic strategies and interventions to mitigate the adverse effects of this condition on both mothers and their offspring. Researchers have elucidated that targeting inflammasomes using anti-inflammatory drugs and compounds can effectively reduce inflammation in GDM. Furthermore, the addition of nuclear factor erythroid 2-related factor 2 (Nrf2) to this complex mechanism opens novel avenues for therapeutics. The antioxidant properties of Nrf2 may potentially suppress inflammasome activation in GDM. This comprehensive review investigates the intricate relationship between inflammasomes and GDM, emphasizing the pivotal role of inflammation in its pathogenesis. It also sheds light on potential therapeutic strategies targeting inflammasome activation and explores the role of Nrf2 in mitigating inflammation in GDM.

[Biomarkers of atherothrombotic and cardioembolic subtypes of acute ischemic stroke]

OBJECTIVE

To evaluate the concentrations of CC-chemokines and stable metabolites of nitric oxide (NO) and endothelin-1 (ET-1) in patients with atherothrombotic (AT) and cardioembolic (CE) subtypes of ischemic stroke (IS) in the acute period.

MATERIAL AND METHODS

Sixty patients diagnosed with IS in the carotid basin were examined. Group 1 included 30 patients with AT, group 2 - 30 patients with CE subtype of IS. The control group consisted of 20 age-matched patients without a history of stroke. All patients were assessed on admission for functional status using the Barthel Index (BI), the Modified Rankin Scale (mRS) and the National Institutes of Health Stroke Scale (NIHSS). Neuroimaging parameters were assessed using CT/MRI data. Laboratory diagnostics included assessment of serum concentrations of interleukin (IL)-1β, IL-6, IL-16, interferon gamma (IFN-γ), CC-chemokines (CCL2, CCL-7, CCL8, CCL13, CCL15, CCL23) and stable metabolites of NO and ET-1.

RESULTS

All patients with IS had moderate stroke severity scores according to NIHSS, BI and mRS. Analysis of the indices of the main clinical scales revealed.

higher NIHSS scores, the prevalence of body mass index (BMI), the size of IS foci and the presence of multifocal lesions in patients of group 2. Compared with the control group, a significant increase of IFN- γ and IL-16 was noted in patients of both groups; ET-1, CCL2 and CCL15 were elevated in group 1; IL-1β, IL-6, CCL8 and CCL23 - in group 2. A comparative analysis between groups revealed higher concentrations of ET-1, CCL2 and CCL15 in group 1 and the increase of IL-1β, IL-6, IL-16 and CCL13 in group 2.

CONCLUSION

The results allow considering cytokines CCL23, IL-6, IL-16, IL-1β and IFN-γ as indicators of IS severity; CCL2, CCL15 and ET-1 as important regulators of atherogenesis and indicators of the AT subtype of IS; IL-1β, IL-6 and CCL13 as markers of complications of atrial fibrillation. The findings indicate the necessity of multicentre studies with a large sample size to determine the potential value of CCR1/CCR2 chemokines and stable metabolites as biomarkers of course of different IS subtypes.

Astrocytic expression of Yes-associated protein (YAP) regulates retinal neovascularization in a mouse model of oxygen-induced retinopathy

Pathological neovascularization is the hallmark of many vascular oculopathies. There is still a great deal of uncertainty surrounding retinal neovascularization research. A working hypothesis that astrocytic Yes-associated protein (YAP) act as a key factor in retinal neovascularization was proposed. And our study was conducted to verified this hypothesis. In vivo, we successfully generated mice deficient in YAP in astrocytes (YAPf/f GFAP-Cre mice) and set up oxygen-induced retinopathy (OIR) model. Pathological neovascularization was evaluated by immunofluorescence staining and western blotting. In vitro, cultured retinal astrocytes were transfected with YAP siRNA. Enzyme-linked immunosorbent assay (ELISA) and western blot were used to determine the proteins in the supernatants and cells. The results showed that YAP was upregulated and activated in the OIR mice retinas. Conditional ablation of YAP aggravated pathological neovascularization, along with the upregulation of vascular endothelial growth factor A (VEGF-A) and monocyte chemoattractant protein-1 (MCP-1). Studies in vitro confirmed that the knockdown of YAP in astrocytes lead to increases in VEGF-A and MCP-1 levels, thus enhancing pro-angiogenic capability of YAP-deficit astrocytes. In conclusion, astrocytic YAP alleviates retinal pathological angiogenesis by inhibiting the over-activation of astrocytes, which suppresses excessive VEGF-A production and neuroinflammation.

Serum resolvin D1 potentially predicts neurofunctional recovery, the risk of recurrence and death in patients with acute ischemic stroke

Resolvin D1 (RvD1) represses inflammation, oxidative damage and neural injury related to acute ischemic stroke (AIS) progression. The present study aimed to explore the association of serum RvD1 with disease features, neurological recovery and prognosis in patients with AIS. A total of 212 patients with newly diagnosed AIS, whose serum RvD1 was quantified at admission and at discharge using an ELISA were enrolled in the current study. The modified Rankin scale (mRS) score was noted at 3 months after patient enrolment (M3), and patients were followed up for a median duration of 11.4 (range, 1.1-21.0) months. The median RvD1 in patients with AIS at admission was 1.07 (range, 0.11-9.29) ng/ml and it was negatively correlated with the neutrophil/lymphocyte ratio (r=-0.160; P=0.009) and C-reactive protein level (r=-0.272; P<0.001), but it was not correlated with comorbidities or other biochemical indexes. RvD1 at admission was lower in patients with mRS >2 at M3 (P=0.001), recurrence (P=0.001) or death (P=0.032) compared with that in patients without the aforementioned characteristics, which had a general ability to estimate mRS >2 at M3 [area under curve (AUC), 0.633], as well as lower risk of recurrence (AUC, 0.745) and death (AUC, 0.757) according to receiver operator characteristic (ROC) curve analyses. The median RvD1 was raised to 1.70 (range, 0.30-16.62) ng/ml at discharge. RvD1 at discharge was able to forecast mRS >2 at M3 (AUC, 0.678) and was able to predict the risk of recurrence (AUC, 0.796) and death (AUC, 0.826) in the ROC curve analyses. Increased serum RvD1 was associated with an attenuated inflammation status, and predicted improved neurological recovery, and lower risk of recurrence and death in patients with AIS. More specifically, its level at discharge exhibits a better prognostic utility than that at admission.

[Indicators of cognitive impairment of varying severity in the acute period of ischemic stroke]

OBJECTIVE

To assess phenotype and identify biomarkers of cognitive impairment (CI) of varying severity in patients in the acute period of ischemic stroke (IS) based on the analysis of clinical and paraclinical indicators.

MATERIAL AND METHODS

Two hundred and forty patients with diagnosed IS and presence of CI were examined. Depending on the scores on the Montreal Cognitive Assessment Scale, patients were divided into two groups: group 1 (n=182) with mild CI, group 2 (n=58) with dementia. On admission, stroke severity according to the National Institutes of Health Stroke Scale (NIHSS), activities of daily living assessed by the Barthel Scale and patient independence assessed by the modified Rankin Scale (mRS) were determined. Neuropsychological examination was performed on day 14 and included investigation of episodic memory, executive functions, speech, gnosis, praxis, and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) parameters. Immunological diagnostics included a study of the concentration of cytokines of various groups (interleukin (IL)-1b, IL-6, IL-16, granulocyte-macrophage colony-stimulating factor (GM-CSF), chemokines CXCL10, CXCL11, CXCL9, tumor necrosis factor α (TNFα)). Neuroimaging parameters were assessed using brain MRI data with verification of the STRIVE criteria and the medial temporal lobe atrophy scale (MTA). The standard application software package SPSS Statistics, Pandas and SciPy libraries were used for statistical analysis.

RESULTS

Patients of group 2 had lower scores in all cognitive domains with the greatest reduction in perception, constructive praxis, semantic information processing and mnestic function. These analyses revealed a higher degree of IQCODE, prevalence of features corresponding to STRIVE/MTA criteria in patients of group 2, while patients of group 1 had higher NIHSS and mRS scores. When serum concentrations of cytokines were assessed, patients of group 1 showed higher concentrations of IL-1b, IL-6, GM-CSF and TNFα, while group 2 patients had higher concentrations of cytokine CXCL10.

CONCLUSION

The presence of pre-stroke CI, baseline indicators of the patient's functional status, neuroimaging parameters of MTA/STRIVE and age are reflected in the structure and severity of cognitive deficit in the acute period of IS. Investigation of the role of interleukins, GM-CSF, TNFα and CXCL10 in the pathogenesis of IS and their association with the progression of post-stroke CI requires further studies with a larger sample size and longer follow-up period.

Drivers of Chronic Pathology Following Ischemic Stroke: A Descriptive Review

Stroke is the third leading cause of death and long-term disability in the world. Considered largely a disease of aging, its global economic and healthcare burden is expected to rise as more people survive into advanced age. With recent advances in acute stroke management, including the expansion of time windows for treatment with intravenous thrombolysis and mechanical thrombectomy, we are likely to see an increase in survival rates. It is therefore critically important to understand the complete pathophysiology of ischemic stroke, both in the acute and subacute stages and during the chronic phase in the months and years following an ischemic event. One of the most clinically relevant aspects of the chronic sequelae of stroke is its extended negative effect on cognition. Cognitive impairment may be related to the deterioration and dysfunctional reorganization of white matter seen at later timepoints after stroke, as well as ongoing progressive neurodegeneration. The vasculature of the brain also undergoes significant insult and remodeling following stroke, undergoing changes which may further contribute to chronic stroke pathology. While inflammation and the immune response are well established drivers of acute stroke pathology, the chronicity and functional role of innate and adaptive immune responses in the post-ischemic brain and in the peripheral environment remain largely uncharacterized. In this review, we summarize the current literature on post-stroke injury progression, its chronic pathological features, and the putative secondary injury mechanisms underlying the development of cognitive impairment and dementia. We present findings from clinical and experimental studies and discuss the long-term effects of ischemic stroke on both brain anatomy and functional outcome. Identifying mechanisms that occur months to years after injury could lead to treatment strategies in the chronic phase of stroke to help mitigate stroke-associated cognitive decline in patients.

Fingerprint of Circulating Immunocytes as Biomarkers for the Prognosis of Brain Inflammation and Neuronal Injury after Cardiac Arrest

Cardiac arrest is one of the most dangerous health problems in the world. Outcome prognosis is largely based on cerebral performance categories determined by neurological evaluations. Few systemic tests are currently available to predict survival to hospital discharge. Here, we present the results from the preclinical studies of cardiac arrest and resuscitation (CAR) in mice to identify signatures of circulating immune cells as blood-derived biomarkers to predict outcomes after CAR. Two flow cytometry panels for circulating blood lymphocytes and myeloid-derived cells, respectively, were designed to correlate with neuroinflammation and neuronal and dendritic losses in the selectively vulnerable regions of bilateral hippocampi. We found that CD4+CD25+ regulatory T cells, CD11b+CD11c- and CD11b+Ly6C+Ly6G+ myeloid-derived cells, and cells positive for the costimulatory molecules CD80 and CD86 in the blood were correlated with activation of microglia and astrocytosis, and CD4+CD25+ T cells are additionally correlated with neuronal and dendritic losses. A fingerprint pattern of blood T cells and monocytes is devised as a diagnostic tool to predict CAR outcomes. Blood tests aimed at identifying these immunocyte patterns in cardiac arrest patients will guide future clinical trials to establish better prognostication tools to avoid unnecessary early withdrawal from life-sustaining treatment.

Disparities in cardio-oncology: Implication of angiogenesis, inflammation, and chemotherapy

Cancers and cardiovascular diseases are the top two causes of death in the United States. Over the past decades, novel therapies have slowed the cancer mortality rate, yet cardiac failures have risen due to the toxicity of cancer treatments. The mechanisms behind this relationship are poorly understood and it is crucial that we properly treat patients at risk of developing cardiac failure in response to cancer treatments. Currently, we rely on early-stage biomarkers of inflammation and angiogenesis to detect cardiotoxicity before it becomes irreversible. Identification of such biomarkers allows healthcare professionals to decrease the adverse effects of cancer therapies. Angiogenesis and inflammation have a systemic influence on the heart and vasculature following cancer therapy. In the field of cardio-oncology, there has been a recent emphasis on gender and racial disparities in cardiotoxicity and the impact of these disparities on disease outcomes, but there is a scarcity of data on how cardiotoxicity varies across diverse populations. Here, we will discuss how current markers of angiogenesis and inflammation induced by cancer therapy are related to disparities in cardiovascular health.

Heterogeneity of T cells in periapical lesions and in vitro validation of the proangiogenic effect of GZMA on HUVECs

AIM

T cells are key immunomodulatory cells in periapical lesions. This study aimed to explore the roles of T cells in chronic apical periodontitis (CAP) using single-cell RNA sequencing and to further investigate Granzyme A (GZMA) in angiogenesis regulation.

METHODOLOGY

A total of five CAP samples were collected for single-cell RNA sequencing. We performed subcluster and lineage-tracing analyses for T cells. According to differential gene expression, distinct biological functions enriched in T cells of CAP were presented by gene set enrichment analysis (GSEA) and compared with healthy gingiva (data obtained from the GEO database). CellChat was used to explore potential ligand-receptor interactions between T cells and endothelial cells in CAP. The coculture of primary human umbilical vein endothelial cells (HUVECs) and Jurkat T cells, as well as the addition of GZMA recombinant protein, was used to validate the predicted pair of GZMA and coagulation factor II thrombin receptor (F2R) by RT-PCR, angiogenesis and migration assays.

RESULTS

A transcriptomic atlas of 44 746 individual cells was constructed from the periapical lesions of five patients with CAP by single-cell RNA-seq, and eight cell types were identified. We identified nine subsets of T cells and deciphered the cellular heterogeneity of T cells in CAP at the functional level by subclustering and GSEA. Lineage tracing revealed a distinct lineage of T cells in CAP and predicted the transition of the T cellular state upon CAP. GSEA revealed multiple biological processes and relevant angiogenesis genes upregulated in CAP T cells. GZMA-F2R pairs were predicted by cell-cell interactions in CAP. High expression of GZMA and F2R was observed in the coculture of HUVECs and Jurkat T cells, and the proangiogenic capacity of the GZMA recombinant protein was emphasized by in vitro experiments.

CONCLUSIONS

Our study provides novel insights into the heterogeneity of T cells in periapical lesions and reveals the potential role of GZMA in T cells in regulating angiogenesis in HUVECs.

Integrative Approaches in Acute Ischemic Stroke: From Symptom Recognition to Future Innovations

Among the high prevalence of cerebrovascular diseases nowadays, acute ischemic stroke stands out, representing a significant worldwide health issue with important socio-economic implications. Prompt diagnosis and intervention are important milestones for the management of this multifaceted pathology, making understanding the various stroke-onset symptoms crucial. A key role in acute ischemic stroke management is emphasizing the essential role of a multi-disciplinary team, therefore, increasing the efficiency of recognition and treatment. Neuroimaging and neuroradiology have evolved dramatically over the years, with multiple approaches that provide a higher understanding of the morphological aspects as well as timely recognition of cerebral artery occlusions for effective therapy planning. Regarding the treatment matter, the pharmacological approach, particularly fibrinolytic therapy, has its merits and challenges. Endovascular thrombectomy, a game-changer in stroke management, has witnessed significant advances, with technologies like stent retrievers and aspiration catheters playing pivotal roles. For select patients, combining pharmacological and endovascular strategies offers evidence-backed benefits. The aim of our comprehensive study on acute ischemic stroke is to efficiently compare the current therapies, recognize novel possibilities from the literature, and describe the state of the art in the interdisciplinary approach to acute ischemic stroke. As we aspire for holistic patient management, the emphasis is not just on medical intervention but also on physical therapy, mental health, and community engagement. The future holds promising innovations, with artificial intelligence poised to reshape stroke diagnostics and treatments. Bridging the gap between groundbreaking research and clinical practice remains a challenge, urging continuous collaboration and research.

The Circadian System Is Essential for the Crosstalk of VEGF-Notch-mediated Endothelial Angiogenesis in Ischemic Stroke

Ischemic stroke is a major public health problem worldwide. Although the circadian clock is involved in the process of ischemic stroke, the exact mechanism of the circadian clock in regulating angiogenesis after cerebral infarction remains unclear. In the present study, we determined that environmental circadian disruption (ECD) increased the stroke severity and impaired angiogenesis in the rat middle cerebral artery occlusion model, by measuring the infarct volume, neurological tests, and angiogenesis-related protein. We further report that Bmal1 plays an irreplaceable role in angiogenesis. Overexpression of Bmal1 promoted tube-forming, migration, and wound healing, and upregulated the vascular endothelial growth factor (VEGF) and Notch pathway protein levels. This promoting effect was reversed by the Notch pathway inhibitor DAPT, according to the results of angiogenesis capacity and VEGF pathway protein level. In conclusion, our study reveals the intervention of ECD in angiogenesis in ischemic stroke and further identifies the exact mechanism by which Bmal1 regulates angiogenesis through the VEGF-Notch1 pathway.

Neuroinflammatory Dysfunction of the Blood-Brain Barrier and Basement Membrane Dysplasia Play a Role in the Development of Drug-Resistant Epilepsy

Drug-resistance epilepsy (DRE) is a key problem in neurology. It is possible that damage to the blood-brain barrier (BBB) may affect resistance in DRE. The aim of this work was to assess the damage and dysfunction in the BBB in the area of epileptic foci in patients with DRE under conditions of neuroinflammation. The changes to the BBB in temporal lobe epilepsy (by immunohistochemistry and transmission electron microscopy), levels of neuroinflammatory proteins, and cytokine levels in the blood (by multiplex analysis) were studied. Increased levels of vascular endothelial growth factor (VEGF) and growth-regulated protein (GRO), and decreased levels of epidermal growth factor (EGF) in plasma, combined with overexpression of the VEGF-A receptor by endotheliocytes were detected. Malformation-like growths of the basement membrane of the capillaries of the brain complicate the delivery of antiepileptic drugs (AEDs). Dysplasia of the basement membrane is the result of inadequate reparative processes in chronic inflammation. In conclusion, it should be noted that damage to the microcirculatory network of the brain should be considered one of the leading factors contributing to DRE.

Potential enhancement of post-stroke angiogenic response by targeting the oligomeric aggregation of p53 protein

Tumor suppressor gene p53 and its aggregate have been found to be involved in many angiogenesis-related pathways. We explored the possible p53 aggregation formation mechanisms commonly occur after ischemic stroke, such as hypoxia and the presence of reactive oxygen species (ROS). The angiogenic pathways involving p53 mainly occur in nucleus or cytoplasm, with one exception that occurs in mitochondria. Considering the high mitochondrial density in brain and endothelial cells, we proposed that the cyclophilin D (CypD)-dependent vascular endothelial cell (VECs) necrosis pathway occurring in the mitochondria is one of the major factors that affects angiogenesis. Hence, targeting p53 aggregation, a key intermediate in the pathway, could be an alternative therapeutic target for post-stroke management.

Isoflurane Anesthesia's Impact on Gene Expression Patterns of Rat Brains in an Ischemic Stroke Model

BACKGROUND

Ischemic stroke (IS) is one of the most severe brain diseases. Animal models with anesthesia are actively used to study stroke genomics and pathogenesis. However, the anesthesia-related gene expression patterns of ischemic rat brains remain poorly understood. In this study, we sought to elucidate the impact of isoflurane (ISO) anesthesia on the extent of ischemic brain damage and gene expression changes associated with stroke.

METHODS

We used the transient middle cerebral artery occlusion (tMCAO) model under long-term and short-term ISO anesthesia, magnetic resonance imaging (MRI), RNA sequencing, and bioinformatics.

RESULTS

We revealed that the volume of cerebral damage at 24 h after tMCAO was inversely proportional to the duration of ISO anesthesia. Then, we revealed hundreds of overlapping ischemia-related differentially expressed genes (DEGs) with a cutoff of >1.5; Padj < 0.05, and 694 and 1557 DEGs only under long-term and short-term anesthesia, respectively, using sham-operated controls. Concomitantly, unique DEGs identified under short-term anesthesia were mainly associated with neurosignaling systems, whereas unique DEGs identified under long-term anesthesia were predominantly related to the inflammatory response.

CONCLUSIONS

We were able to determine the effects of the duration of anesthesia using isoflurane on the transcriptomes in the brains of rats at 24 h after tMCAO. Thus, specific genome responses may be useful in developing potential approaches to reduce damaged areas after cerebral ischemia and neuroprotection.

Therapeutic effects of a standardized-flavonoid Diospyros kaki L.f. leaf extract on transient focal cerebral ischemia-induced brain injury in mice

This study aimed to investigate the neuroprotective and therapeutic effects of Diospyros kaki L.f. leaves (DK) on transient focal cerebral ischemic injury and underlying mechanisms using a middle cerebral artery occlusion (MCAO) model of mice. The animals received the MCAO operation on day 0. The daily administrations of DK (50 and 100 mg/kg, p.o) and edaravone (6 mg/kg, i.v), a reference drug with radical scavenging activity, were started 7 days before (pre-treatment) or immediately after the MCAO operation (post-treatment) and continued during the experimental period. Histochemical, biochemical, and neurological changes and cognitive performance were evaluated. MCAO caused cerebral infarction and neuronal cell loss in the cortex, striatum, and hippocampus in a manner accompanied by spatial cognitive deficits. These neurological and cognitive impairments caused by MCAO were significantly attenuated by pre- and post-ischemic treatments with DK and edaravone, suggesting that DK, like edaravone, has therapeutic potential for cerebral ischemia-induced brain damage. DK and edaravone suppressed MCAO-induced changes in biomarkers for apoptosis (TUNEL-positive cell number and cleaved caspase-3 protein expression) and oxidative stress (glutathione and malondialdehyde contents) in the brain. Interestingly, DK, but not edaravone, mitigated an increase in blood-brain permeability and down-regulation of vascular endothelial growth factor protein expression caused by MCAO. Although the exact chemical constituents implicated in the effects of DK remain to be clarified, the present results indicate that DK exerts neuroprotective and therapeutic activity against transient focal cerebral ischemia-induced injury probably by suppressing oxidative stress, apoptotic process, and mechanisms impairing blood-brain barrier integrity in the brain.

Extracellular Vesicles as Delivery Shippers for Noncoding RNA-Based Modulation of Angiogenesis: Insights from Ischemic Stroke and Cancer

Ischemic stroke and systemic cancer are two of the leading causes of mortality. Hypoxia is a central pathophysiological component in ischemic stroke and cancer, representing a joint medical function. This function includes angiogenesis regulation. Vascular remodeling coupled with axonal outgrowth following cerebral ischemia is critical in improving poststroke neurological functional recovery. Antiangiogenic strategies can inhibit cancer vascularization and play a vital role in impeding cancer growth, invasion, and metastasis. Although there are significant differences in the cause of angiogenesis across both pathophysiological conditions, emerging evidence states that common signaling structures, such as extracellular vesicles (EVs) and noncoding RNAs (ncRNAs), are involved in this context. EVs, heterogeneous membrane vesicles encapsulating proteomic genetic information from parental cells, act as multifunctional regulators of intercellular communication. Among the multifaceted roles in modulating biological responses, exhaustive evidence shows that ncRNAs are selectively sorted into EVs, modulating common specific aspects of cancer development and stroke prognosis, namely, angiogenesis. This review will discuss recent advancements in the EV-facilitated/inhibited progression of specific elements of angiogenesis with a particular concern about ncRNAs within these vesicles. The review is concluded by underlining the clinical opportunities of EV-derived ncRNAs as diagnostic, prognostic, and therapeutic agents.

Shaping the brain vasculature in development and disease in the single-cell era

The CNS critically relies on the formation and proper function of its vasculature during development, adult homeostasis and disease. Angiogenesis - the formation of new blood vessels - is highly active during brain development, enters almost complete quiescence in the healthy adult brain and is reactivated in vascular-dependent brain pathologies such as brain vascular malformations and brain tumours. Despite major advances in the understanding of the cellular and molecular mechanisms driving angiogenesis in peripheral tissues, developmental signalling pathways orchestrating angiogenic processes in the healthy and the diseased CNS remain incompletely understood. Molecular signalling pathways of the 'neurovascular link' defining common mechanisms of nerve and vessel wiring have emerged as crucial regulators of peripheral vascular growth, but their relevance for angiogenesis in brain development and disease remains largely unexplored. Here we review the current knowledge of general and CNS-specific mechanisms of angiogenesis during brain development and in brain vascular malformations and brain tumours, including how key molecular signalling pathways are reactivated in vascular-dependent diseases. We also discuss how these topics can be studied in the single-cell multi-omics era.

Friends or foes: The mononuclear phagocyte system in ischemic stroke

Ischemic stroke (IS) is a major cause of disability and death in adults, and the immune response plays an indispensable role in its pathological process. After the onset of IS, an inflammatory storm, with the infiltration and mobilization of the mononuclear phagocyte system (MPS), is triggered in the brain. Microglia are rapidly activated in situ, followed by waves of circulating monocytes into the ischemic area. Activated microglia and monocytes/macrophages are mainly distributed in the peri-infarct area. These cells have similar morphology and functions, such as secreting cytokines and phagocytosis. Previously, the presence of the MPS was considered a marker of an exacerbated inflammatory response that contributes to brain damage. However, recent studies have suggested a rather complicated role of the MPS in IS. Here, we reviewed articles focusing on various functions of the MPS among different phases of IS, including recruitment, polarization, phagocytosis, angiogenesis, and interaction with other types of cells. Moreover, due to the characteristics of the MPS, we also noted clinical research addressing alterations in the MPS as potential biomarkers for IS patients for the purposes of predicting prognosis and developing novel therapeutic strategies.

Exosomes for angiogenesis induction in ischemic disorders

Ischaemic disorders are leading causes of morbidity and mortality worldwide. While the current therapeutic approaches have improved life expectancy and quality of life, they are unable to "cure" ischemic diseases and instate regeneration of damaged tissues. Exosomes are a class of extracellular vesicles with an average size of 100-150 nm, secreted by many cell types and considered a potent factor of cells for paracrine effects. Since exosomes contain multiple bioactive components such as growth factors, molecular intermediates of different intracellular pathways, microRNAs and nucleic acids, they are considered as cell-free therapeutics. Besides, exosomes do not rise cell therapy concerns such as teratoma formation, alloreactivity and thrombotic events. In addition, exosomes are stored and utilized more convenient. Interestingly, exosomes could be an ideal complementary therapeutic tool for ischemic disorders. In this review, we discussed therapeutic functions of exosomes in ischemic disorders including angiogenesis induction through various mechanisms with specific attention to vascular endothelial growth factor pathway. Furthermore, different delivery routes of exosomes and different modification strategies including cell preconditioning, gene modification and bioconjugation, were highlighted. Finally, pre-clinical and clinical investigations in which exosomes were used were discussed.