Immune responses to stroke: mechanisms, modulation, and therapeutic potential

Epigenetic regulation of the inflammatory response in stroke

Stroke is classified as ischemic or hemorrhagic, and there are few effective treatments for either type. Immunologic mechanisms play a critical role in secondary brain injury following a stroke, which manifests as cytokine release, blood-brain barrier disruption, neuronal cell death, and ultimately behavioral impairment. Suppressing the inflammatory response has been shown to mitigate this cascade of events in experimental stroke models. However, in clinical trials of anti-inflammatory agents, long-term immunosuppression has not demonstrated significant clinical benefits for patients. This may be attributable to the dichotomous roles of inflammation in both tissue injury and repair, as well as the complex pathophysiologic inflammatory processes in stroke. Inhibiting acute harmful inflammatory responses or inducing a phenotypic shift from a pro-inflammatory to an anti-inflammatory state at specific time points after a stroke are alternative and promising therapeutic strategies. Identifying agents that can modulate inflammation requires a detailed understanding of the inflammatory processes of stroke. Furthermore, epigenetic reprogramming plays a crucial role in modulating post-stroke inflammation and can potentially be exploited for stroke management. In this review, we summarize current findings on the epigenetic regulation of the inflammatory response in stroke, focusing on key signaling pathways including nuclear factor-kappa B, Janus kinase/signal transducer and activator of transcription, and mitogen-activated protein kinase as well as inflammasome activation. We also discuss promising molecular targets for stroke treatment. The evidence to date indicates that therapeutic targeting of the epigenetic regulation of inflammation can shift the balance from inflammation-induced tissue injury to repair following stroke, leading to improved post-stroke outcomes.

Investigating the shared genetic architecture between anxiety and stroke

BACKGROUND

An epidemiological association between anxiety and stroke is well-established; however, the role of shared genetic factors remain unclear. This study aimed to investigate the shared genetic architecture between anxiety and stroke.

METHODS

Using public genome-wide association study (GWAS) summary statistics of anxiety and stroke, we performed linkage disequilibrium score regression and super genetic covariance analyzer for global and local genetic correlation studies. Risk single nucleotide polymorphisms (SNPs) were identified through genome-wide association meta-analysis, multi-trait analysis of GWAS and PLINK, followed by functional mapping and annotation. Additionally, we conducted transcriptome-wide association studies to explore the relationship between genes and associated disease risk.

RESULTS

Our analysis revealed a significant genome-wide genetic correlation between anxiety and stroke. We also identified one previously unreported significant SNP (rs62099231), one risk loci, as well as identified three shared risk genes for anxiety and stroke (WDR6, CCDC71, NCKIPSD).

CONCLUSION

Our study demonstrated a shared genetic structure between anxiety and stroke, enhancing our understanding of their pathogenesis and highlighting potential therapeutic targets.

Calycosin‑7‑O‑β‑D‑glucoside downregulates mitophagy by mitigating mitochondrial fission to protect HT22 cells from oxygen‑glucose deprivation/reperfusion‑induced injury

Calycosin‑7‑O‑β‑D‑glucoside (CG), a major active ingredient of Astragali Radix, exerts neuroprotective effects against cerebral ischemia; however, whether the effects of CG are associated with mitochondrial protection remains unclear. The present study explored the role of CG in improving mitochondrial function in a HT22 cell model of oxygen‑glucose deprivation/reperfusion (OGD/R). The Cell Counting Kit‑8 assay, flow cytometry, immunofluorescence and western blotting were performed to investigate the effects of CG on mitochondrial function. The results demonstrated that mitochondrial function was restored after treatment with CG, as indicated by reduced mitochondrial reactive oxygen species levels, increased mitochondrial membrane potential and improved mitochondrial morphology. Overactivated mitophagy was revealed to be inhibited by the regulation of proteins involved in fission [phosphorylated‑dynamin‑related protein 1 (Drp1) and Drp1] and mitophagy (LC3, p62 and translocase of outer mitochondrial membrane 20), and mitochondrial biogenesis was demonstrated to be enhanced by increased levels of sirtuin 1 (SIRT1) and peroxisome proliferator‑activated receptor γ coactivator‑1α (PGC‑1α). In addition, neuronal apoptosis was ameliorated by CG, as determined by a decreased rate of apoptosis, and levels of caspase‑3 and Bcl‑2/Bax. In conclusion, the present study demonstrated that CG may alleviate OGD/R‑induced injury by upregulating SIRT1 and PGC‑1α protein expression, and reducing excessive mitochondrial fission and overactivation of mitophagy.

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.

Time of day dependent reduction in stroke infarct volume by the Reverb agonist SR9009 in mice

Ischemic stroke leads to disability and death worldwide and evidence suggests that stroke severity is affected by the time dimension of the stroke. Rev-Erbα regulates the core circadian clock through repression of the positive clock element Bmal1. However, it remains unclear if a Rev-Erbα agonist (SR9009) alleviates stroke pathology in mice. We found that stroke reduces the level of Rev-Erbα and elevates neuroinflammation and stroke severity at zeitgeber time (ZT) ZT06. Therefore, we hypothesized that SR9009 treatment may reduce neuroinflammation and stroke severity in a mouse suture occlusion model. At 12 to 14 weeks, C57BL/6 J (Wild Type, n = 5-10 mice/group) mice were randomly assigned to undergo MCAO stroke for 60 min at either zeitgeber time ZT06 (MCAO-ZT06-sleep phase) or ZT18 (MCAO-ZT18-awake phase). Stroked mice were treated with SR9009 (100 mg/kg) or vehicle at 1 h and 24 h after MCAO. After forty-eight hours of stroke, TTC staining, Western blot, and qRT-PCR were performed. We found that SR9009 treatment alleviates neuroinflammation and infarct volume by Rev-Erb remodeling in ZT06 stroke mice but not in ZT18 stroke mice. Additionally, monocytic and neutrophilic NLRP3 as well as brain NLRP3 levels were reduced by SR9009 treatment in ZT06 stroke though no effects were observed at ZT18 stroke. SR9009 also reduced TNFα expression and increased IL-10 expression in blood and brain in ZT06 stroke mice and no differences were observed at ZT18. There were no significant effects of SR9009 on neurological deficit score and sensorimotor function at ZT06 or ZT18 at 48 h. Our study demonstrates that SR9009 treatment reduces stroke volume, circulating immune response, circadian expression, and that the protection was circadian- and treatment time-dependent.

Benzydamine attenuates microglia-mediated neuroinflammation and ischemic brain injury by targeting cathepsin s

Microglia, the primary immune cells of the central nervous system, play a crucial role in the neuroinflammatory processes following ischemic stroke. Targeting neuroinflammation is a promising strategy to enhance the outcomes of ischemic stroke. Benzydamine (BA), a well-known non-steroidal anti-inflammatory drug, has demonstrated potential in inhibiting pro-inflammatory cytokines across various disease models. However, the potential role of BA in microglial activation and post-stroke neuroinflammation remains unclear. Our study reveals that BA effectively suppresses the lipopolysaccharide (LPS)-stimulated pro-inflammatory responses of primary microglia, with high-dose BA (10 μM) suppressing LPS-induced inflammatory markers by up to 59.1 % in the mRNA levels of IL-1β. Furthermore, BA mitigated ischemic brain injury in experimental stroke mice. BA treatment also significantly attenuated neuroinflammatory responses and attenuates ischemic brain injury in experimental stroke mice. Further investigation revealed that BA reduces the release of the LPS-stimulated pro-inflammatory factors and activation of primary microglia by directly binding to and inhibiting the activity of cathepsin S (CTSS). In conclusion, our study identifies BA as a promising CTSS inhibitor with potential to suppress neuroinflammation following ischemic stroke. Our findings provide a theoretical basis for developing new neuroprotective strategies.

Construction of an lncRNA-mediated ceRNA network to investigate the inflammatory regulatory mechanisms of ischemic stroke

Long non-coding RNAs (lncRNAs) are among the most abundant types of non-coding RNAs in the genome and exhibit particularly high expression levels in the brain, where they play crucial roles in various neurophysiological and neuropathological processes. Although ischemic stroke is a complex multifactorial disease, the involvement of brain-derived lncRNAs in its intricate regulatory networks remains inadequately understood. In this study, we established a cerebral ischemia-reperfusion injury model using middle cerebral artery occlusion (MCAO) in male Sprague-Dawley rats. High-throughput sequencing was performed to profile the expression of cortical lncRNAs post-stroke, with subsequent validation using RT-PCR and qRT-PCR. Among the 31,183 lncRNAs detected in the rat cerebral cortex, 551 were differentially expressed between the MCAO and sham-operated groups in the ipsilateral cortex (fold change ≥2.0, P < 0.05). An integrated analysis of the 20 most abundant and significantly differentially expressed lncRNAs (DELs) identified 25 core cytoplasmic DELs, which were used to construct an interaction network based on their targeting relationships. This led to the establishment of a comprehensive lncRNA-miRNA-mRNA regulatory network comprising 12 lncRNAs, 16 sponge miRNAs, and 191 target mRNAs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed that differentially expressed mRNAs (DEmRNAs) were significantly enriched in stroke-related pathways. Our analysis predicted four key lncRNAs, four miRNAs, and eleven crucial mRNAs involved in post-transcriptional regulation through competing endogenous RNA (ceRNA) mechanisms. These molecules were shown to participate extensively in post-stroke processes, including angiogenesis, axonal regeneration, inflammatory responses, microglial activation, blood-brain barrier (BBB) disruption, apoptosis, autophagy, ferroptosis, and thrombocytopenia. These findings highlight the role of lncRNAs as multi-level regulators in the complex network of post-stroke mechanisms, providing novel insights into the pathophysiological processes of stroke.

Modified human mesenchymal stromal/stem cells restore cortical excitability after focal ischemic stroke in rats

Allogeneic modified bone marrow-derived human mesenchymal stromal/stem cells (hMSC-SB623 cells) are in clinical development for the treatment of chronic motor deficits after traumatic brain injury and cerebral ischemic stroke. However, their exact mechanisms of action remain unclear. Here, we investigated the effects of this cell therapy on cortical network excitability, brain tissue, and peripheral blood at a chronic stage after ischemic stroke in a rat model. One month after focal cortical ischemic stroke, hMSC-SB623 cells or the vehicle solution were injected into the peri-stroke cortex. Starting one week after treatment, cortical excitability was assessed ex vivo. hMSC-SB623 cell transplants reduced stroke-induced cortical hyperexcitability, restoring cortical excitability to control levels. The histology of brain tissue revealed an increase of factors relevant to neuroregeneration, and synaptic and cellular plasticity. Whole-blood RNA sequencing and serum protein analyses showed that intra-cortical hMSC-SB623 cell transplantation reversed effects of stroke on peripheral blood factors known to be involved in stroke pathophysiology. Our findings demonstrate that intra-cortical transplants of hMSC-SB623 cells correct stroke-induced circuit disruptions even at the chronic stage, suggesting broad usefulness as a therapeutic for neurological conditions with network hyperexcitability. Additionally, the transplanted cells exert far-reaching immunomodulatory effects whose therapeutic impact remains to be explored.

Targeting MAPK14 in microglial cells: neuroimmune implications of Panax ginseng in post-stroke inflammation

AIM

This study investigates the molecular mechanisms through which Panax ginseng and Panax notoginseng saponin (PNS) mitigate neuroinflammatory damage and promote neural repair postischemic stroke, utilizing bioinformatics, and experimental approaches.

BACKGROUND

Cerebral infarction significantly contributes to disability worldwide, with chronic neuroinflammation worsening cognitive impairments and leading to neurodegenerative diseases. Addressing neuroimmune interactions is crucial for slowing disease progression and enhancing patient recovery, highlighting the need for advanced research in neuroimmune regulatory mechanisms and therapeutic strategies.

OBJECTIVE

To elucidate the effects of the traditional Chinese medicine components Panax ginseng and PNS on neuroinflammatory damage following ischemic stroke, focusing on the molecular pathways involved in mitigating inflammation and facilitating neural repair.

METHODS

The study employs single-cell sequencing and transcriptomic analysis to investigate gene expression changes associated with cerebral infarction. Gene set enrichment analysis and weighted gene co-expression network analysis are used to identify key molecular markers and core genes. Furthermore, pharmacological profiling, including functional assays, assesses the impact of Ginsenoside-Rc, a PNS derivative, on microglial cell viability, cytokine production, and reactive oxygen species (ROS) levels.

RESULTS

Our analysis revealed that MAPK14 is a critical mediator in the neuroinflammatory response to ischemic stroke. Ginsenoside-Rc potentially targets and modulates MAPK14 activity to suppress inflammation. Experimental validation showed that Ginsenoside-Rc treatment, combined with MAPK14 silencing, significantly alters MAPK14 expression and mitigates neuroinflammatory damage, evidenced by reduced microglial cell death, inflammatory factor secretion, and ROS production.

CONCLUSION

Ginsenoside-Rc's modulation of MAPK14 offers a promising therapeutic strategy for reducing neuroinflammation and potentially improving cognitive recovery post-ischemic stroke. This supports the therapeutic application of the traditional Chinese medicine Sanqi in ischemic stroke care, providing a theoretical and experimental foundation for its use.

OTHERS

Future work will focus on extending these findings through clinical trials to evaluate the efficacy and safety of Ginsenoside-Rc in human subjects, aiming to translate these promising preclinical results into practical therapeutic interventions for ischemic stroke recovery.

Long non-coding RNA OIP5-AS1 protects neurons from ischemia-reperfusion injury and inhibits neuronal apoptosis through TAB-2

Ischemic stroke represents a highly perilous cerebrovascular disorder, involving a variety of complex pathophysiological mechanisms. OIP5 antisense RNA 1 (OIP5-AS1) is a long non-coding RNA (LncRNA) that has been shown to play a pivotal role in a variety of disease systems. However, there are relatively few studies on ischemic stroke. This research aimed to elucidate the direct impact of OIP5-AS1 on neuronal cells following cerebral ischemia-reperfusion. Our study revealed a significant reduction in OIP5-AS1 expression in mouse neurons following middle cerebral artery occlusion/reperfusion (MCAO/R). Overexpression of OIP5-AS1 in neurons inhibits neuronal apoptosis induced by cerebral ischemia-reperfusion injury (CIRI) and exerts a neuroprotective role. Mechanistically, OIP5-AS1 may play a neuroprotective role after CIRI by up-regulating the expression of TAK1 binding protein 2 (TAB-2), reducing neuronal mitochondrial damage, and inhibiting apoptosis. OIP5-AS1 may become a novel therapeutic target for ischemic stroke.

RiboTag RNA Sequencing Identifies Local Translation of HSP70 in Astrocyte Endfeet After Cerebral Ischemia

Brain ischemia causes disruption in cerebral blood flow and blood-brain barrier integrity, which are normally maintained by astrocyte endfeet. Emerging evidence points to dysregulation of the astrocyte translatome during ischemia, but its effects on the endfoot translatome are unknown. In this study, we aimed to investigate the early effects of ischemia on the astrocyte endfoot translatome in a rodent cerebral ischemia and reperfusion model of stroke. To do so, we immunoprecipitated astrocyte-specific tagged ribosomes (RiboTag IP) from mechanically isolated brain microvessels. In mice subjected to middle cerebral artery occlusion and reperfusion and contralateral controls, we sequenced ribosome-bound RNAs from perivascular astrocyte endfeet and identified 205 genes that were differentially expressed in the endfoot translatome after ischemia. The main biological processes associated with these differentially expressed genes included proteostasis, inflammation, cell cycle/death, and metabolism. Transcription factors whose targets were enriched amongst upregulated translating genes included HSF1, the master regulator of the heat shock response. The most highly upregulated genes in the translatome were HSF1-dependent Hspa1a and Hspa1b, which encode the inducible HSP70. Using qPCR, Western blot, and immunohistochemistry, we confirmed that HSP70 is upregulated in astrocyte endfeet after ischemia. This coincided with an increase in ubiquitination across the proteome that suggests that ischemia induces a disruption in proteostasis in astrocyte endfeet. These findings suggest a robust proteostasis response to proteotoxic stress in the endfoot translatome after ischemia. Modulating proteostasis in endfeet may be a strategy to preserve endfoot function and BBB integrity after ischemic stroke.

Mechanism of inflammatory response and therapeutic effects of stem cells in ischemic stroke: current evidence and future perspectives

Ischemic stroke is a leading cause of death and disability worldwide, with an increasing trend and tendency for onset at a younger age. China, in particular, bears a high burden of stroke cases. In recent years, the inflammatory response after stroke has become a research hotspot: understanding the role of inflammatory response in tissue damage and repair following ischemic stroke is an important direction for its treatment. This review summarizes several major cells involved in the inflammatory response following ischemic stroke, including microglia, neutrophils, monocytes, lymphocytes, and astrocytes. Additionally, we have also highlighted the recent progress in various treatments for ischemic stroke, particularly in the field of stem cell therapy. Overall, understanding the complex interactions between inflammation and ischemic stroke can provide valuable insights for developing treatment strategies and improving patient outcomes. Stem cell therapy may potentially become an important component of ischemic stroke treatment.

Non-coding RNAs in acute ischemic stroke: from brain to periphery

Acute ischemic stroke is a clinical emergency and a condition with high morbidity, mortality, and disability. Accurate predictive, diagnostic, and prognostic biomarkers and effective therapeutic targets for acute ischemic stroke remain undetermined. With innovations in high-throughput gene sequencing analysis, many aberrantly expressed non-coding RNAs (ncRNAs) in the brain and peripheral blood after acute ischemic stroke have been found in clinical samples and experimental models. Differentially expressed ncRNAs in the post-stroke brain were demonstrated to play vital roles in pathological processes, leading to neuroprotection or deterioration, thus ncRNAs can serve as therapeutic targets in acute ischemic stroke. Moreover, distinctly expressed ncRNAs in the peripheral blood can be used as biomarkers for acute ischemic stroke prediction, diagnosis, and prognosis. In particular, ncRNAs in peripheral immune cells were recently shown to be involved in the peripheral and brain immune response after acute ischemic stroke. In this review, we consolidate the latest progress of research into the roles of ncRNAs (microRNAs, long ncRNAs, and circular RNAs) in the pathological processes of acute ischemic stroke-induced brain damage, as well as the potential of these ncRNAs to act as biomarkers for acute ischemic stroke prediction, diagnosis, and prognosis. Findings from this review will provide novel ideas for the clinical application of ncRNAs in acute ischemic stroke.

Research progress of small-molecule natural medicines for the treatment of ischemic stroke

Stroke is the second leading cause of disability and mortality worldwide, imposing a substantial socioeconomic burden on individuals and healthcare systems. Annually, approximately 14 million people experience stroke, with ischemic stroke comprising nearly 85% of cases, of which 10% to 20% involve large vessel occlusions. Currently, recombinant tissue plasminogen activator (tPA) remains the only approved pharmacological intervention. However, its utility is limited due to a narrow therapeutic window and low recanalization rates, making it applicable to only a minority of patients. Therefore, there is an urgent need for novel therapeutic strategies, including pharmacological advancements and combinatory treatments. Small-molecule natural medicines, particularly those derived from traditional Chinese herbs, have demonstrated significant therapeutic potential in ischemic stroke management. These compounds exert multiple neuroprotective effects, such as antioxidation, anti-inflammatory action, and inhibition of apoptosis, all of which are critical in mitigating stroke-induced cerebral damage. This review comprehensively examines the pathophysiology of acute ischemic stroke (AIS) and highlights the recent progress in the development of small-molecule natural medicines as promising therapeutic agents for cerebral ischemic stroke.

Association of physical activity, sedentary behavior and stroke in older adults

Objective

The aim of this study was to investigate the relationship between physical activity, sedentary behavior and stroke in people aged 60 years and older.

Methods

The study included 3,010 participants aged 60 and older from the National Health and Nutrition Examination Survey (NHANES). Data on sedentary behavior, physical activity and stroke were obtained through questionnaires. Statistical analyses were performed using a complex multistage sampling design and weighted multivariate logistic regression. Smoothed curve fitting and threshold effects analyses were used to explore non-linear relationships between physical activity, sedentary behavior and stroke.

Results

There were 244 (7.53%) participants aged 60 years and older who had experienced a stroke. After adjusting for all covariates, physical activity, sedentary behavior and stroke were significantly associated [OR (95% CI) for physical activity: 0.622 (0.443, 0.875), p = 0.009; OR (95% CI) for sedentary behavior: 2.602 (1.557, 4.348), p = 0.003]. C-reactive protein mediated the association between sedentary behavior and stroke among older adults, with a mediation of 3.64%.

Conclusion

In people aged 60 years and older, sedentary behavior was positively associated with stroke, whereas physical activity was negatively associated with stroke, and C-reactive protein mediated the relationship between sedentary behavior and stroke.

Mendelian randomization and mediation examination of the immune cell-mediated link between sphingomyelin and stroke

OBJECTIVE

The study established a direct link between stroke and sphingomyelin. The precise biology underlying this connection is yet unknown, though. As a result, we decided to investigate the potential causal relationship between Sphingomyelin and genetic vulnerability to stroke, as well as the potential mediating function that immune cells may play in this process, using Mendelian randomization (MR) approaches.

METHODS

A published genome-wide association study (GWAS) dataset of European populations served as the foundation for the MR Study. The inverse variance weighting (IVW) model is the main technique. Four additional statistical techniques (MR Egger, Weighted median, Simple mode, and Weighted mode) were also employed to enhance the verification process. Reverse MR Analysis was utilized to reinforce the findings, and heterogeneity and horizontal pleipotency were assessed. Additionally, this study looked into potential immune cell mediating roles in the causal link between sphingomyelin and stroke using two-step MR techniques.

RESULT

The IVW metod's results indicated that sphingomyelin genetic susceptibility was linked to a high risk of stroke (OR = 1.045 [95 %CI, 1.004-1.087; P = 0.031). Additionally, the statistical result of SSC-A on CD8br and stroke was IVW [P = 0.007, OR(95 % CI) 1.020 (1.005-1.034)], which was proportionate to the increased risk of stroke. A lower incidence of stroke IVW is linked to CD45 on CD8br [P = 0.004, OR(95 % CI) 0.993 (0.988-0.998)]. Furthermore, our results imply that SSC-A on CD8br and CD45 on CD8br contribute to the causative relationship between sphingomyelin and stroke. The percentages of conciliation are 5.38 %, 22.7 %, 33.5 %), and 0.000999, 0.0152, 0.0132, respectively.

CONCLUSION

We confirmed the effect of sphingomyelin on stroke and conducted in-depth studies. SSC-A on CD8br and CD45 on CD8br is latent stroke mediators associated with sphingomyelin. Through two-step mediated Mendelian randomization analysis, we provide new insights into the etiology and treatment of stroke.

Interplay of cell death pathways and immune responses in ischemic stroke: insights into novel biomarkers

Stroke is a severe neurological disease and a major worldwide issue, mostly manifesting as ischemic stroke (IS). In order to create effective treatments for IS, it is imperative to fully understand the underlying pathologies, as the existing therapeutic choices are inadequate. Recent investigations have shown the complex relationships between several programmed cell death (PCD) pathways, including necroptosis, ferroptosis, and pyroptosis, and their correlation with immune responses during IS. However, this relationship is still unclear. To address this gap, this review study explored the cellular interactions in the immune microenvironment of IS. Then, to validate prior findings and uncover biomarkers, the study investigated bioinformatics studies. Several pathways, including nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), Toll-like receptor 4 (TLR4), and receptor-interacting protein kinase (RIPK), were involved in PCD-immune interactions. The bioinformatics studies reported key biomarkers such as glutathione peroxidase 4 (GPX4), NOD-like receptor family pyrin domain containing 3 (NLRP3), gasdermin D (GSDMD), and TLR4, which have important implications in ferroptosis, cuproptosis, pyroptosis, and necroptosis respectively. These biomarkers were associated with PCD mechanisms such as oxidative stress and inflammatory reactions. The immune infiltration analysis consistently revealed a significant correlation between PCD pathways and detrimental immune cells, such as neutrophils and γδ T cells. Conversely, M2 macrophages and T helper cells showed protective effects. In conclusion, considering the intricate network of interactions between immune responses and PCD pathways, this study emphasized the necessity of a paradigm shift in therapeutic approaches to address the injuries that are related to this complex network.

Association between red cell distribution width-to-lymphocyte ratio and 30-day mortality in patients with ischemic stroke: a retrospective cohort study

OBJECTIVES

Ischaemic stroke (IS) has become a major health problem globally as it is one of the leading causes of long-term disability and death. This study aimed to evaluate the association between red cell distribution width (RDW) to lymphocyte (LYM) ratio (RLR) and 30-day mortality risk in patients with IS.

METHODS

The present study employed a retrospectively cohort study design with the adult data extracted from the Medical Information Mart for Intensive Care (MIMIC-III, MIMIC-IV) databases between 2001 and 2019. The RLR was measured using RDW and LYM. Confounders were adjusted in Cox proportional hazards model. The outcome was 30-day mortality. Univariable and multivariable Cox proportional hazards models were establised. A further analysis was conducted on the basis of subgroup stratification by heart failure (HF) (yes or no), atrial fibrillation or flutter (yes or no), hypertension (yes or no), dyslipidemia (yes or no), sepsis (yes or no), and age (≥ 65 years and < 65 years).

RESULTS

In this study, 1,127 adult patients with IS were finally identified. Among them,818 patients survived (the survival group) and 309 patients died (the death group). The mean age was older in individuals from the death group than those from the survival group (70.19 years vs. 64.56 years). The elevated levels of RLR were linked to an increased risk of mortality within 30 days in patients with IS, with an HR of 1.70 (95% CI: 1.34-2.17). Subgroup analyses showed that high RLR levels was a significant risk factor for mortality at 30 days particularly in IS patients aged ≥ 65 years, HF, no atrial fibrillation or flutter, no hypertension, no dyslipidemia, and no sepsis.

CONCLUSION

Our study shows that high levels of RLR were associated with an increased risk of 30-day mortality in patients with IS, providing additional prognostic information for the treatment and supportive care of these patients.

Immune mechanisms and shared immune targets in neurodegenerative diseases

The immune system plays a major part in neurodegenerative diseases. In some, such as multiple sclerosis, it is the primary driver of the disease. In others, such as Alzheimer disease, amyotrophic lateral sclerosis and Parkinson disease, it has an amplifying role. Immunotherapeutic approaches that target the adaptive and innate immune systems are being explored for the treatment of almost all neurological diseases, and the targets and approaches are often common across diseases. Microglia are the primary immune cells in the brain that contribute to disease pathogenesis, and are consequently a common immune target for therapy. Other therapeutic approaches target components of the peripheral immune system, such as regulatory T cells and monocytes, which in turn act within the CNS. This Review considers in detail how microglia, monocytes and T cells contribute to the pathogenesis of multiple sclerosis, Alzheimer disease, amyotrophic lateral sclerosis and Parkinson disease, and their potential as shared therapeutic targets across these diseases. The microbiome is also highlighted as an emerging therapeutic target that indirectly modulates the immune system. Therapeutic approaches being developed to target immune function in neurodegenerative diseases are discussed, highlighting how immune-based approaches developed to treat one disease could be applicable to multiple other neurological diseases.

Lactate modulates microglial inflammatory responses through HIF-1α-mediated CCL7 signaling after cerebral ischemia in mice

Lactate is a potent regulator of neuroinflammation. We recently demonstrated that lactate alleviated neuronal injury via HIF-1α-regulated microglial inflammation after oxygen-glucose deprivation (OGD). However, the underlying mechanisms and the effect of lactate on microglial responses after ischemic stroke remained unknown. Mouse acute cerebral ischemia-reperfusion injury was induced by middle cerebral artery occlusion (MCAO). L-lactate (100 mM, 2 μl) was intracerebroventricularly administrated 30 min after the reperfusion. Microglia responses were evidenced by the expression of multiple markers such as CD86, iNOS, arginase-1, CD206 and Ym1 in the peri-infarction 24 h after MCAO using western blot analysis and quantitative real-time PCR. Inflammatory factors IL-6, TNF-α, TGF-β and IL-10, as well as NF-κB signaling were also detected. Infarct size and neuronal apoptosis in the peri-infarction at 24 h, mice survival within 7 days and long-term neurobehavioral function were evaluated. The involvement of HIF-1α in lactate-mediated microglial inflammation after MCAO was assessed using a HIF-1α inhibitor. Additionally, transcriptome analysis was used to identify the potential lactate targets in BV2 cells after OGD. The recombinant product of the identified CCL7 gene was used to verify its effect on cerebral ischemia-reperfusion injury in vivo. Lactate supplementation reduced infarction volume, neuronal apoptosis and neurological deficits. Lactate reduced the expression of CD86, iNOS, IL-6, TNF-α and elevated the expression of arginase-1, CD206, Ym1, TGF-β and IL-10 in the peri-infarction at 24 h after reperfusion. Consistently, lactate inhibited the NF-κB signaling. Additionally, lactate upregulated HIF-1α in microglia 24 h after reperfusion, while inhibition of HIF-1α reversed the effects of lactate on brain damage and neuroinflammation after cerebral ischemia. Furthermore, CCL7 was identified as the top down-regulated inflammatory gene induced by lactate in OGD-treated BV2 cells. It was also found high expression of CCL7 in the peri-infarction at 24 h after reperfusion and lactate treatment inhibited CCL7 expression. However, HIF-1α inhibitor reversed the effect of lactate treatment on CCL7 expression. Finally, supplementation of recombinant CCL7 reversed the mitigated neuroinflammation and neuroprotective effect rendered by lactate treatment after MCAO. We concluded that treatment with lactate modulated the microglia inflammatory responses and alleviated cerebral ischemia injury. The inhibition of CCL7/NF-κB signaling by HIF-1α might be involved in the beneficial effect of lactate treatment.

Exploring the Role of Chemokine-Related Gene Deregulation and Immune Infiltration in Ischemic Stroke: Insights into CXCL16 and SEMA3E as Potential Biomarkers

Ischemic stroke is a leading cause of mortality and disability globally. Understanding the role of chemokine-related differently expressed genes (CDGs) in ischemic stroke pathophysiology is essential for advancing diagnostic and therapeutic strategies. We conducted comprehensive analyses using the GSE16561 dataset: chemokine pathway enrichment via GSVA, differential expression of 12 CDGs, Pearson correlation, and functional enrichment analyses (GO and KEGG). Machine learning algorithms were employed to develop diagnostic models, evaluated using ROC curve analysis. A nomogram was constructed and validated with independent datasets (GSE58294). Gene set enrichment analysis (GSEA) and immuno-infiltration analysis were also performed. Chemokine pathway scores were significantly elevated in ischemic stroke, indicating their potential involvement. Logistic regression emerged as the most effective diagnostic model, with CXCL16 and SEMA3E as significant biomarkers. The nomogram exhibited high discriminatory ability (AUC = 0.964), well-calibrated predictions, and clinical utility across datasets. GSEA highlighted key biological pathways associated with CXCL16 and SEMA3E. Immuno-infiltration analysis revealed significant differences in immune cell infiltration between control and ischemic stroke groups, with distinct correlations between CXCL16 and SEMA3E expression and immune cell populations. This study highlights the deregulation of CDGs in ischemic stroke and their implications in critical biological processes. CXCL16 and SEMA3E are identified as key biomarkers with potential diagnostic utility. Insights from gene set enrichment and immuno-infiltration analyses provide mechanistic understanding, suggesting novel therapeutic targets and enhancing clinical decision-making in ischemic stroke management.

Triolein alleviates ischemic stroke brain injury by regulating autophagy and inflammation through the AKT/mTOR signaling pathway

BACKGROUND

Triolein, a symmetric triglyceride exhibiting anti-inflammatory and antioxidant properties, has demonstrated potential in mitigating cellular damage. However, its therapeutic efficacy in ischemic stroke (IS) and underlying molecular mechanisms remain elusive. Given the critical roles of inflammation and autophagy in IS pathogenesis, this study aimed to elucidate the effects of triolein in IS and investigate its mechanism of action.

METHODS

We evaluated the impact of triolein using both in vitro oxygen-glucose deprivation/reoxygenation (OGD/R) and in vivo middle cerebral artery occlusion (MCAO/R) models. Neurological function and cerebral infarct volume were assessed 72 h post-reperfusion. Autophagy was quantified through monodansyl cadaverine (MDC) labeling of autophagic vesicles and Western blot analysis of autophagy-related proteins. Microglial activation was visualized via immunofluorescence, while inflammatory cytokine expression was quantified using RT-qPCR. The cytoprotective effect of triolein on OGD/R-induced HT22 cells was evaluated using Cell Counting Kit-8 and lactate dehydrogenase release assays. The involvement of the Protein kinase B/Mechanistic target of rapamycin kinase (AKT/mTOR) pathway was assessed through Western blot analysis.

RESULTS

Triolein administration significantly reduced infarct volume, enhanced neurological recovery, and attenuated M1 microglial activation and inflammation in MCAO/R-induced mice. Western blot analysis and MDC labeling revealed that triolein exerted an inhibitory effect on post-IS autophagy. Notably, in the BV2-induced OGD/R model, triolein demonstrated an autophagy-dependent suppression of the inflammatory response. Furthermore, triolein inhibited the activation of the AKT/mTOR signaling pathway, consequently attenuating autophagy and mitigating the post-IS inflammatory response.

CONCLUSIONS

This study provides novel evidence that triolein exerts neuroprotective effects by inhibiting post-stroke inflammation through an autophagy-dependent mechanism. Moreover, the modulation of the AKT/mTOR signaling pathway appears to be integral to the neuroprotective efficacy of triolein. These findings elucidate potential therapeutic strategies for IS management and warrant further investigation.

The fuzzy MAD stroke conjecture, using Fuzzy C Means to classify multimodal apparent diffusion for ischemic stroke lesion stratification

BACKGROUND

In conjunction with an epidemiologically determined treatment window, current radiological acute ischemic stroke practice discerns two lesion (stage) types: core (dead tissue, identified by diffusion-weighted imaging (DWI)) and penumbra (tissue region receiving just enough blood flow to be potentially salvageable, identified by the perfusion diffusion mismatch). However, advancements in preclinical and clinical studies have indicated that this approach may be too rigid, warranting a more fine-grained patient-tailored approach. This study aimed to demonstrate the ability to noninvasively provide insights into the current in vivo stroke lesion cascade.

METHODS

To elucidate a finer-grained depiction of the acute focal ischemic stroke cascade in vivo, we retrospectively applied our multimodal apparent diffusion (MAD) method to multi-b-value DWI, up to a b-value of 10,000 s/mm2 in 34 patients with acute focal ischemic stroke. Fuzzy C Means was used to cluster the MAD parameters.

RESULTS

We discerned 18 clusters consistent with normal appearing tissue (NAT) types and 14 potential ischemic lesion (stage) types, providing insights into the variability and aggressiveness of lesion progression and current anomalous stroke-related imaging features. Of the 529 ischemic stroke lesion instances previously identified by two radiologists, 493 (92 %) were autonomously identified; 460 (87 %) were identified as efficaciously or better than the radiologists.

CONCLUSIONS

The data analyzed included a small number of clinical patients without follow-up or contemporaneous histology; therefor, the findings and theorizing should be treated as conjecture. Nevertheless, each identified NAT and lesion type is consistent with the known underpinnings of physiological tissues and pathological ischemic stroke lesion (stage) types. Several findings should be considered in current clinical imaging: WM fluid accumulation, BBB compromise conundrum, b1000 identified core may not be dead tissue, and a practical reason for DWI (pseudo) normalization.

Cortistatin exerts an immunomodulatory and neuroprotective role in a preclinical model of ischemic stroke

Ischemic stroke is the result of a permanent or transient occlusion of a brain artery, leading to irreversible tissue injury and long-term sequelae. Despite ongoing advancements in revascularization techniques, stroke remains the second leading cause of death worldwide. A comprehensive understanding of the complex and interconnected mechanisms, along with the endogenous mediators that modulate stroke responses is essential for the development of effective interventions. Our study investigates cortistatin, a neuropeptide extensively distributed in the immune and central nervous systems, known for its immunomodulatory properties. With neuroinflammation and peripheral immune deregulation as key pathological features of brain ischemia, cortistatin emerges as a promising therapeutic candidate. To this aim, we evaluated its potential effect in a well-established middle cerebral artery occlusion (MCAO) preclinical stroke model. Our findings indicated that the peripheral administration of cortistatin at 24 h post-stroke significantly reduced neurological damage and enhanced recovery. Importantly, cortistatin-induced neuroprotection was multitargeted, as it modulated the glial reactivity and astrocytic scar formation, facilitated blood-brain barrier recovery, and regulated local and systemic immune dysfunction. Surprisingly, administration of cortistatin at immediate and early post-stroke time points proved to be not beneficial and even detrimental. These results emphasize the importance of understanding the spatio-temporal dynamics of stroke pathology to develop innovative therapeutic strategies with appropriate time windows. Premature interruption of certain neuroinflammatory processes might inadvertently compromise neuroprotective mechanisms. In summary, our study highlights cortistatin as a novel pleiotropic therapeutic approach against ischemic stroke, offering new treatment options for patients who undergo early revascularization intervention but unsuccessful recovery.

Perioperative complications of middle cerebral artery occlusion in rats alleviated by human umbilical cord mesenchymal stem cells

For acute ischemic stroke treatment, the limitations of treatment methods and the high incidence of perioperative complications seriously affect the survival rate and postoperative recovery of patients. Human umbilical cord mesenchymal stem cells (hucMSCs) have multi-directional differentiation potential and immune regulation function, which is a potential cell therapy. The present investigation involved developing a model of cerebral ischemia-reperfusion injury by thrombectomy after middle cerebral artery occlusion (MCAO) for 90 min in rats and utilizing comprehensive multi-system evaluation methods, including the detection of brain tissue ischemia, postoperative survival rate, neurological score, anesthesia recovery monitoring, pain evaluation, stress response, and postoperative pulmonary complications, to elucidate the curative effect of tail vein injection of hucMSCs on MCAO's perioperative complications. Based on our research, it has been determined that hucMSCs treatment can reduce the volume of brain tissue ischemia, promote the recovery of neurological function, and improve the postoperative survival rate of MCAO in rats. At the same time, hucMSCs treatment can prolong the time of anesthesia recovery, relieve the occurrence of delirium during anesthesia recovery, and also have a good control effect on postoperative weight loss, facial pain expression, and lung injury. It can also reduce postoperative stress response by regulating blood glucose and serum levels of stress-related proteins including TNF-α, IL-6, CRP, NE, cortisol, β-endorphin, and IL-10, and ultimately promote the recovery of MCAO's perioperative complications.

The Role of Gut Microbiota in Blood-Brain Barrier Disruption after Stroke

Growing evidence has proved that alterations in the gut microbiota have been linked to neurological disorders including stroke. Structural and functional disruption of the blood-brain barrier (BBB) is observed after stroke. In this context, there is pioneering evidence supporting that gut microbiota may be involved in the pathogenesis of stroke by regulating the BBB function. However, only a few experimental studies have been performed on stroke models to observe the BBB by altering the structure of gut microbiota, which warrant further exploration. Therefore, in order to provide a novel mechanism for stroke and highlight new insights into BBB modification as a stroke intervention, this review summarizes existing evidence of the relationship between gut microbiota and BBB integrity and discusses the mechanisms of gut microbiota on BBB dysfunction and its role in stroke.

Assessment of corticospinal tract damage and cytokines response in early and late stages of acute unilateral brainstem infarction patients

Background

Acute brainstem infarction is associated with high morbidity and mortality, the integrity of corticospinal tract (CST) detected via diffusion tensor imaging (DTI) can assist in predicting the motor recovery of the patients. In addition to the damage caused by ischemia and reperfusion, sterile inflammation also contributes to the brain injury after stroke. However, the changes in CST integrity detected by DTI in acute brainstem infarction have yet to be fully elucidated, and it is still unclear whether sterile inflammation can cause damage to the CST.

Methods

In this study, the acute brainstem infarction patients in the early (EABI patients, n = 19) and late (LABI patients, n = 21) stages and healthy controls (HCs, n = 22) are employed. The probabilistic tractography technique was used and the fractional anisotropy (FA) value was chosen to evaluated the integrity of the CST, the IL-6, IL-10, IL-17, IL-1β, and tumor necrosis factor (TNF)-α levels in the plasma are measured to evaluate the level of inflammation.

Results

Compared to the HCs (F = 13.634, p ANOVA < 0.001), the CST FA values on the infarcted side were abnormally elevated in EABI patients (p LSD = 0.003), and decreased in LABI patients (p LSD = 0.034). The levels of IL-6 (F = 12.311, p ANOVA < 0.001, EABI vs HCs: p LSD < 0.001, LABI vs HCs: p LSD < 0.001), IL-10 (F = 11.329, p ANOVA < 0.001, EABI vs HCs: p LSD < 0.001, LABI vs HCs: p LSD = 0.017) and IL-1β (F = 15.986, p ANOVA < 0.001, EABI vs HCs: p LSD < 0.001, LABI vs HCs: p LSD < 0.001) were increased in both EABI and LABI patients, while the IL-17 levels were elevated only in LABI patients (F = 4.258, p ANOVA = 0.019, LABI vs HCs: p LSD = 0.027). Among these cytokines, the increased IL-6 (r = 0.663, p = 0.002) and IL-1β (r = 0.615, p = 0.005) levels of EABI patients might be related to the elevated CST FA values, while the increased IL-17 (r = -0.599, p = 0.004) levels of LABI patients might contribute to the decrease of the CST FA values.

Conclusion

Our study reveals that the increased CST FA values in EABI patients may include signals generated by the immune cells which move along the CST. The sterile inflammation may contribute to the impairment of CST integrity in LABI patients.

Mechanistic exploration of ubiquitination-mediated pathways in cerebral ischemic injury

The ubiquitin-proteasome system (UPS) plays a pivotal role in regulating protein homeostasis and cellular processes, including protein degradation, trafficking, DNA repair, and cell signaling. During cerebral ischemia, ischemic conditions profoundly disrupt UPS activity, leading to proteasomal dysfunction and the accumulation of abnormal proteins. This imbalance contributes to neuronal injury and cell death observed in ischemic stroke. The UPS is intricately linked to various signaling pathways crucial for neuronal survival, inflammation, and cellular stress response, such as NF-κB, TRIM, TRIP, JAK-STAT, PI3K/Akt, and ERK1/2. Alterations in the ubiquitination process can significantly impact the activation and regulation of these pathways, exacerbating ischemic brain injury. Therapeutic approaches targeting the UPS in cerebral ischemia aim to rebalance protein levels, reduce proteotoxic stress, and mitigate neuronal injury. Strategies include proteasome inhibition, targeting specific ubiquitin ligases and deubiquitinating enzymes, and modulating ubiquitination-mediated regulation of key signaling pathways implicated in ischemia-induced pathophysiology. Therefore, the present review discusses the molecular mechanisms underlying UPS dysfunction in ischemic stroke is crucial for developing effective therapeutic interventions. Modulating ubiquitination-mediated pathways through therapeutic interventions targeting specific UPS components holds significant promise for mitigating ischemic brain injury and promoting neuroprotection and functional recovery in patients with cerebral ischemia.

Decoding senescence of aging single cells at the nexus of biomaterials, microfluidics, and spatial omics

Aging has profound effects on the body, most notably an increase in the prevalence of several diseases. An important aging hallmark is the presence of senescent cells that no longer multiply nor die off properly. Another characteristic is an altered immune system that fails to properly self-surveil. In this multi-player aging process, cellular senescence induces a change in the secretory phenotype, known as senescence-associated secretory phenotype (SASP), of many cells with the intention of recruiting immune cells to accelerate the clearance of these damaged senescent cells. However, the SASP phenotype results in inducing secondary senescence of nearby cells, resulting in those cells becoming senescent, and improper immune activation resulting in a state of chronic inflammation, called inflammaging, in many diseases. Senescence in immune cells, termed immunosenescence, results in further dysregulation of the immune system. An interdisciplinary approach is needed to physiologically assess aging changes of the immune system at the cellular and tissue level. Thus, the intersection of biomaterials, microfluidics, and spatial omics has great potential to collectively model aging and immunosenescence. Each of these approaches mimics unique aspects of the body undergoes as a part of aging. This perspective highlights the key aspects of how biomaterials provide non-cellular cues to cell aging, microfluidics recapitulate flow-induced and multi-cellular dynamics, and spatial omics analyses dissect the coordination of several biomarkers of senescence as a function of cell interactions in distinct tissue environments. An overview of how senescence and immune dysregulation play a role in organ aging, cancer, wound healing, Alzheimer's, and osteoporosis is included. To illuminate the societal impact of aging, an increasing trend in anti-senescence and anti-aging interventions, including pharmacological interventions, medical procedures, and lifestyle changes is discussed, including further context of senescence.

Inhibition of PCSK9 Protects against Cerebral Ischemia‒Reperfusion Injury via Attenuating Microcirculatory Dysfunction

Proprotein convertase substilin/kexin type 9 (PCSK9), a pivotal protein regulating lipid metabolism, has been implicated in promoting microthrombotic formation and inflammatory cascades, thereby contributing to cardiovascular ischemia/reperfusion (I/R) injury. However, its involvement in cerebral I/R injury and its potential role in microcirculation protection remain unexplored. In this investigation, we utilized a middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model to simulate ischemic stroke. Different concentrations of evolocumab (1, 5, 10 mg/kg, i.v.), a PCSK9 inhibitor, were administered to assess its impact. Immunofluorescence staining was employed to analyze changes in the expression of occludin, claudin-5, thrombocyte, ICAM-1, VCAM-1, and CD45, providing insights into blood-brain barrier integrity, platelet adhesion, and immune cell infiltration. Moreover, the Morris water maze and elevated plus maze were utilized to evaluate neurological and behavioral functions in MCAO/R mice, shedding light on the effects of PCSK9 inhibition. Our findings revealed a surge in plasma PCSK9 levels post-MCAO/R, peaking at 24 h post-reperfusion. Evolocumab (10 mg/kg) treatment significantly mitigated brain infarction and neurological deficits, evidenced by enhanced locomotor function and reduced post-stroke anxiety. However, it did not ameliorate cognitive impairment following MCAO/R. Additionally, evolocumab administration led to diminished leakage of evans blue solution and upregulated expression of occludin and claudin-5. Thrombocyte, ICAM-1, VCAM-1, and CD45 levels were notably reduced in the penumbral area post-evolocumab treatment. These protective effects are speculated to be mediated through the inhibition of the ERK/NF-κB pathway. The PCSK9 inhibitor evolocumab holds promise as a therapeutic agent during the acute phase of stroke, exerting its beneficial effects by modulating the ERK/NF-κB signaling pathway.

Soluble Urokinase-Type Plasminogen Activator Receptor and Inflammatory Biomarker Response with Prognostic Significance after Acute Neuronal Injury - a Prospective Cohort Study

Aneurysmal subarachnoid hemorrhage (aSAH), ischemic stroke (IS), and traumatic brain injury (TBI) are severe conditions impacting individuals and society. Identifying reliable prognostic biomarkers for predicting survival or recovery remains a challenge. Soluble urokinase type plasminogen activator receptor (suPAR) has gained attention as a potential prognostic biomarker in acute sepsis. This study evaluates suPAR and related neuroinflammatory biomarkers in serum for brain injury prognosis. This prospective study included 31 aSAH, 30 IS, 13 TBI, and three healthy controls (n = 77). Serum samples were collected on average 5.9 days post-injury, analyzing suPAR, IL-1β, cyclophilin A, and TNFα levels using ELISA. Outcomes were assessed 90 days post-injury with the modified Rankin Scale (mRS), categorized as favorable (mRS 0-2) or unfavorable (mRS 3-6). Statistical analyses included 2-tailed t-tests, Pearson's correlations, and machine learning linear discriminant analysis (LDA) for biomarker combinations. Elevated suPAR levels were found in brain injury patients compared to controls (p = 0.017). Increased suPAR correlated with unfavorable outcomes (p = 0.0018) and showed prognostic value (AUC = 0.66, p = 0.03). IL-1β levels were higher in the unfavorable group (p = 0.0015). LDA combinatory analysis resulted a fair prognostic accuracy with canonical equation = 0.775[suPAR] + 0.667[IL1-β] (AUC = 0.77, OR 0.296, sensitivity 93.1%, specificity 53.1%, p = 0.0007). No correlation was found between suPAR and CRP or infection status. Elevated suPAR levels in acute brain injury patients were associated with poorer outcomes, highlighting suPAR's potential as a prognostic biomarker across different brain injury types. Combining IL-1β with suPAR improved prognostic accuracy, supporting a multimodal biomarker approach for predicting outcomes.

STING orchestrates microglia polarization via interaction with LC3 in autophagy after ischemia

Autophagy has both protective and pathogenetic effects on injury caused by cerebral ischemia/reperfusion (I/R). Our previous research has indicated that stimulator of interferon genes (STING) could orchestrate microglia polarization following middle cerebral artery occlusion. However, it remains largely unexplored whether STING balances microglial polarization by regulating autophagy in brain I/R injury. Here, STING was observed to show an up-regulation in the microglia from mice subjected to experimental ischemic stroke. Strikingly, the deletion of STING led to the significant skewness of microglia activated by ischemia from a pro- to anti-inflammatory state and substantially alleviated ischemia-induced infarction and neuronal injury. In addition, STING-null mice can restore long-term neurobehavioral function. Then, the crosstalk between neuroinflammation and microglia autophagy was analyzed. The differential activity of autophagy in wild-type and STING-knockout (KO) mice or primary microglia was largely reversed when STING was restored in microglia. Irritating autophagy by rapamycin skewed the anti‑inflammatory state induced by STING-KO to a pro‑inflammatory state in microglia. Furthermore, microtubule-associated protein light-chain-3 (LC3) was identified as the key factor in the STING regulation of autophagy by glutathione-S-transferase (GST) pull-down analysis. Mechanically, STING can directly interact with LC3 through the STING transmembrane domain (1-139aa). Herein, current data determine the pivotal role of autophagy, specifically via LC3 protein, in the regulation of microglial phenotypic transformation by STING. These findings may provide a possible treatment target for delaying the progression of ischemic stroke.

Spatiotemporal transcriptomic map of glial cell response in a mouse model of acute brain ischemia

The role of nonneuronal cells in the resolution of cerebral ischemia remains to be fully understood. To decode key molecular and cellular processes that occur after ischemia, we performed spatial and single-cell transcriptomic profiling of the male mouse brain during the first week of injury. Cortical gene expression was severely disrupted, defined by inflammation and cell death in the lesion core, and glial scar formation orchestrated by multiple cell types on the periphery. The glial scar was identified as a zone with intense cell-cell communication, with prominent ApoE-Trem2 signaling pathway modulating microglial activation. For each of the three major glial populations, an inflammatory-responsive state, resembling the reactive states observed in neurodegenerative contexts, was observed. The recovered spectrum of ischemia-induced oligodendrocyte states supports the emerging hypothesis that oligodendrocytes actively respond to and modulate the neuroinflammatory stimulus. The findings are further supported by analysis of other spatial transcriptomic datasets from different mouse models of ischemic brain injury. Collectively, we present a landmark transcriptomic dataset accompanied by interactive visualization that provides a comprehensive view of spatiotemporal organization of processes in the postischemic mouse brain.

Cognitive function in older adults with stroke: A latent profile analysis

BACKGROUND

Post-stroke cognitive impairment (PSCI) is one of the major complications after a stroke. Therefore, it is necessary to identify different categories of cognitive function in older adults with stroke and to explore factors associated with different levels of cognitive function in older adults after stroke.

METHODS

A cross-sectional survey was conducted using convenience sampling to collect data from 1076 older adults with stroke from 5 hospitals in Lanzhou City, Gansu Province, China, from June 2022 to August 2023. Latent Profile Analysis (LPA) was used to identify cognitive function subgroups among older adults with stroke, and multinomial logistic regression was used to analyze the related factors.

RESULTS

1076 older adults with stroke were identified and classified as class-1: cognitive impairment, class-2: mild cognitive impairment, class-3: normal cognitive function. Age, gender, education level, hemorrhagic stroke, cerebrovascular disease are associated with different levels of cognitive function in older adults after stroke.

CONCLUSIONS

These findings highlight the heterogeneity of cognitive function in older adults with stroke. Our research could assist healthcare professionals in China to identify older adults with a high risk of cognitive impairment and to develop individualized interventions based on their characteristics.

RNF13 protects neurons against ischemia-reperfusion injury via stabilizing p62-mediated Nrf2/HO-1 signaling pathway

BACKGROUND

Cerebral ischemia/reperfusion injury (CIRI), a common, universal clinical problem that costs a large proportion of the economic and disease burden. Identifying the key regulators of cerebral I/R injury could provide potential strategies for clinically improving the prognosis of stroke. Ring finger protein 13 (RNF13) has been proven to be involved in the inflammatory response. Here, we aimed to identify the role of RNF13 in cerebral I/R injury and further reveal its immanent mechanisms.

METHODS

The CRISPR/Cas9 based knockout mice, RNA sequencing, mass spectrometry, co-immunoprecipitation, GST-pull down, immunofluorescent staining, western blot, RT-PCR were used to investigate biodistribution, function and mechanism of RNF13 during cerebral I/R injury.

RESULTS

In the present study, we found that RNF13 was significantly up-regulated in patients, mice and primary neurons after I/R injury. Deficiency of RNF13 aggravated I/R-induced neurological impairment, inflammatory response and apoptosis while overexpression of RNF13 inhibited I/R injury. Mechanistically, this inhibitory effect of RNF13 during I/R injury was confirmed to be dependent on the blocking of TRIM21-mediated autophagy-dependent degradation of p62 and the stabilization of the p62-mediated Nrf2/HO-1 signaling pathway.

CONCLUSION

RNF13 is a crucial regulator of cerebral I/R injury that plays its role in inhibiting cell apoptosis and inflammatory response by preventing the autophagy-medicated degradation of the p62/Nrf2/HO-1 signaling pathway via blocking the interaction of TRIM21-p62 complex. Therefore, RNF13 represents a potential pharmacological target in acute ischemia stroke therapy.

The role of ACSL4 in stroke: mechanisms and potential therapeutic target

Stroke, as a neurological disorder with a poor overall prognosis, has long plagued the patients. Current stroke therapy lacks effective treatments. Ferroptosis has emerged as a prominent subject of discourse across various maladies in recent years. As an emerging therapeutic target, notwithstanding its initial identification in tumor cells associated with brain diseases, it has lately been recognized as a pivotal factor in the pathological progression of stroke. Acyl-CoA synthetase long-chain family member 4 (ACSL4) is a potential target and biomarker of catalytic unsaturated fatty acids mediating ferroptosis in stroke. Specifically, the upregulation of ACSL4 leads to heightened accumulation of lipid peroxidation products and reactive oxygen species (ROS), thereby exacerbating the progression of ferroptosis in neuronal cells. ACSL4 is present in various tissues and involved in multiple pathways of ferroptosis. At present, the pharmacological mechanisms of targeting ACSL4 to inhibit ferroptosis have been found in many drugs, but the molecular mechanisms of targeting ACSL4 are still in the exploratory stage. This paper introduces the physiopathological mechanism of ACSL4 and the current status of the research involved in ferroptosis crosstalk and epigenetics, and summarizes the application status of ACSL4 in modern pharmacology research, and discusses the potential application value of ACSL4 in the field of stroke.

Bioinformatics Approach to Identify the Pathogenetic Link of Gut Microbiota-Derived Short-Chain Fatty Acids and Ischemic Stroke

Stroke is a life-threatening condition that impairs the arteries and causes neurological impairment. The incidence of stroke is increasing year by year with the arrival of the aging population. Thus, there is an urgent need for early stroke diagnosis. Short-chain fatty acids (SCFAs) can modulate the central nervous system and directly and indirectly impact behavioral and cognitive functions. This study aimed to investigate the connection between SCFA metabolism and stroke development via bioinformatic analysis. Initially, the Gene Set Enrichment Analysis (GSEA) and immune cell infiltration analysis were performed based on RNA data from stroke patients to comprehend the mechanisms governing stroke pathogenesis. The functional analysis, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI), was performed based on the Differentially Expressed Gene (DEG) selected by the limma package. 1220 SCFA metabolism-related genes screened from Genecards databases were intersected with 242 genes in main modules determined by Weighted Gene Co-Expression Network Analysis (WGCNA), and the final 10 SCFA key genes were obtained. GO analysis revealed that these genes were involved in immune response processes. Through lasso regression analyses, we established a stroke early diagnosis model and selected 6 genes with diagnostic value. The genes were validated by the area under curve (AUC) values and had a relatively good diagnostic performance. Finally, 4 potential therapeutic drugs targeting these genes were predicted using the Drug Signatures Database (DSigDB) via Enrichr. In conclusion, this paper analyzes the involvement of SCFAs in the complex gut-brain axis mechanism, which contributes to developing new targets for treating central nervous system diseases and provides new ideas for early ischemic stroke diagnosis.

Target modulation of glycolytic pathways as a new strategy for the treatment of neuroinflammatory diseases

Neuroinflammation is an innate and adaptive immune response initiated by the release of inflammatory mediators from various immune cells in response to harmful stimuli. While initially beneficial and protective, prolonged or excessive neuroinflammation has been identified in clinical and experimental studies as a key pathological driver of numerous neurological diseases and an accelerant of the aging process. Glycolysis, the metabolic process that converts glucose to pyruvate or lactate to produce adenosine 5'-triphosphate (ATP), is often dysregulated in many neuroinflammatory disorders and in the affected nerve cells. Enhancing glucose availability and uptake, as well as increasing glycolytic flux through pharmacological or genetic manipulation of glycolytic enzymes, has shown potential protective effects in several animal models of neuroinflammatory diseases. Modulating the glycolytic pathway to improve glucose metabolism and ATP production may help alleviate energy deficiencies associated with these conditions. In this review, we examine six neuroinflammatory diseases-stroke, Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), and depression-and provide evidence supporting the role of glycolysis in their treatment. We also explore the potential link between inflammation-induced aging and glycolysis. Additionally, we briefly discuss the critical role of glycolysis in three types of neuronal cells-neurons, microglia, and astrocytes-within physiological processes. This review highlights the significance of glycolysis in the pathology of neuroinflammatory diseases and its relevance to the aging process.

Progress of Exosomal MicroRNAs and Traditional Chinese Medicine Monomers in Neurodegenerative Diseases

Exosomes, extracellular vesicles secreted by various cells, actively participate in intercellular communication by facilitating the exchange of crucial molecular information such as DNA, RNA, and lipids. Within this intricate network, microRNAs, endogenous non-coding small RNAs, emerge as pivotal regulators of post-transcriptional gene expression, significantly influencing the development of neurodegenerative diseases. The historical prominence of traditional Chinese medicine (TCM) in clinical practice in China underscores its enduring significance. Notably, TCM monomers, serving as active constituents within herbal medicine, assume a critical role in the treatment of neurodegenerative diseases, particularly in mitigating oxidative stress, inhibiting apoptosis, and reducing inflammation. This comprehensive review aims to delineate the specific involvement of exosomal microRNAs in various neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, stroke, and amyotrophic lateral sclerosis. Furthermore, the exploration extends to the application of TCM monomers, elucidating their efficacy as therapeutic agents in these conditions. Additionally, the review examines the utilization of exosomes as drug delivery carriers in the context of neurodegenerative diseases, providing a nuanced understanding of the potential synergies between TCM and modern therapeutic approaches. This synthesis of knowledge aims to contribute to the advancement of our comprehension of the intricate molecular mechanisms underlying neurodegeneration and the potential therapeutic avenues offered by TCcom interventions.

Innate immunity-mediated neuroinflammation promotes the onset and progression of post-stroke depression

Post-stroke depression (PSD) is a prevalent psychiatric disorder after stroke, with the incidence of approximately one-third among stroke survivors. It is classified as an organic mental disorder and has a well-documented association with stroke affecting various aspects of patients, such as the recovery of limb motor function, daily living self-care ability, and increasing the mortality of stroke survivors. However, the pathogenesis of PSD is not yet fully understood. Currently, immune inflammation is a research hotspot. This review focuses on the pathogenesis of PSD, particularly elucidating the role of inflammation in mediating neuroinflammation through innate immunity. Simultaneously, we highlight that peripheral inflammation following a stroke may trigger a detrimental cycle of neuroinflammation by activating innate immune pathways within the central nervous system, which could potentially contribute to the development of PSD. Lastly, we summarize potential treatments for PSD and propose targeting cytokines and innate immune pathways as novel therapeutic approaches.

Constitutive DAMPs in CNS injury: From preclinical insights to clinical perspectives

Damage-associated molecular patterns (DAMPs) are endogenous molecules released in tissues upon cellular damage and necrosis, acting to initiate sterile inflammation. Constitutive DAMPs (cDAMPs) have the particularity to be present within the intracellular compartments of healthy cells, where they exert diverse functions such as regulation of gene expression and cellular homeostasis. However, after injury to the central nervous system (CNS), cDAMPs are rapidly released by stressed, damaged or dying neuronal, glial and endothelial cells, and can trigger inflammation without undergoing structural modifications. Several cDAMPs have been described in the injured CNS, such as interleukin (IL)-1α, IL-33, nucleotides (e.g. ATP), and high-mobility group box protein 1. Once in the extracellular milieu, these molecules are recognized by the remaining surviving cells through specific DAMP-sensing receptors, thereby inducing a cascade of molecular events leading to the production and release of proinflammatory cytokines and chemokines, as well as cell adhesion molecules. The ensuing immune response is necessary to eliminate cellular debris caused by the injury, allowing for damage containment. However, seeing as some molecules associated with the inflammatory response are toxic to surviving resident CNS cells, secondary damage occurs, aggravating injury and exacerbating neurological and behavioral deficits. Thus, a better understanding of these cDAMPs, as well as their receptors and downstream signaling pathways, could lead to identification of novel therapeutic targets for treating CNS injuries such as SCI, TBI, and stroke. In this review, we summarize the recent literature on cDAMPs, their specific functions, and the therapeutic potential of interfering with cDAMPs or their signaling pathways.

Efficacy of different traditional Chinese medicine decoctions in the treatment of ischemic stroke: a network meta-analysis

Objective

Currently, traditional Chinese medicine (TCM) and its combinations are widely used in the treatment and rehabilitation of patients with ischemic stroke. However, current studies should mainly focus on the therapeutic effects of traditional Chinese medicines alone. This paper will employ a network meta-analysis to compare the efficacy of different TCM decoctions in the treatment of patients with ischemic stroke.

Methods

Chinese and English databases including PubMed, Embase, Cochrane Library, and Web of Science were searched to collect randomized controlled trials of TCM decoctions in the treatment of patients with ischemic stroke (IS), with a search time frame until April 2024. A library of references was created using EndNote 21. Quality assessment was performed using the Version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2). A Bayesian network meta-analysis of data was performed using R4.3.1 and STATA 15.0.

Results

A network meta-analysis was conducted on 119 randomized controlled trials including 12,137 IS patients. The following TCM decoctions were involved: Xinglou Chengqi Decoction (XLCQT), Shenqi Tongluo Decoction (SQTLF), Zhongfeng Jiuxian Decoction (ZFJXT), Yiqi Tongluo Decoction (YQTLT), Tongqiao Huoxue Tang (TQHXT), Tongluo Xifeng Decoction (TLXFT), Tongluo Fuzheng Decoction (TLFZT), Xuefu Zhuyu Decoction (XFZYT), Xiaoxuming Decoction (XXMT), Qufeng Xingxue Tongluo Formula (QFXXTLF), Banxia Baizhu Tianma Decoction (BXBZTMT), Buyang Huanwu Tang (BYHWT),Huatan Tongluo Decoction (HTTLT), Yiqi Huoxue Tongluo Decoction (YQHXTLT), Yiqi Huoxue Decoction (YQHXT), and Yiqi Huoxue Kaiqiao Prescription (YQHXKQP). Of them, XFZYT was most effective in reducing the NIHSS score; SQTLF was most effective in increasing the Barthel Index (BI) score; and HTTLT was most effective in improving activities of daily living (ADL).

Conclusion

This network meta-analysis provided data on the relative efficacy of different TCM decoctions. Of them, XFZYT was most effective in reducing the NIHSS score; SQTLF was most effective in increasing the BI score; and HTTLT was most effective in improving the ADL score. At the same time, overall, XFZYT ranked first with its best efficacy regarding all the three outcome measures above, and SQTLF came second with its impact on two of the outcome measures.

Buyang huanwu decoction alleviates stroke-induced immunosuppression in MCAO mice by reducing splenic T cell apoptosis triggered by AIM2 inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

Ischemic stroke is a serious disabling and fatal disease that places a heavy burden on the world. Stroke induces a state of systemic immunosuppression that is strongly associated with an increased risk of infection and severe outcomes. Buyang Huanwu Decoction (BYHWD) is an ancient Chinese traditional formula with a good clinical and experimental basis. However, the role of BYHWD on post-stroke immunomodulation, especially immunosuppression, is unclear.

AIM OF THE STUDY

The aim of this study was to investigate the pharmacological mechanism of BYHWD to alleviate ischemic stroke by analyzing splenic T cells apoptosis triggered by the AIM2 inflammasome activation cascade.

MATERIALS AND METHODS

An ischemic stroke model in C57BL/6 J mice was constructed using the MCAO method. The mNSS test and the hanging wire test were conducted to evaluate neurological impairment in mice. Histopathological damage was visualized by Nissl staining and HE staining. The protective effects of BYHWD on the spleen were determined by splenic index and spleen HE staining. The inhibition of AIM2 inflammasome cascade by BYHWD were explored through immunofluorescence (IF), flow cytometry, enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription polymerase chain reaction (qRT-PCR). Flow cytometry was used to assess the apoptosis of splenic T cells.

RESULTS

BYHWD significantly reduced infarct size, improved neurological function scores, and alleviated histopathological damage in middle cerebral artery occlusion (MCAO) mice. At the same time, BYHWD salvaged spleen atrophy. BYHWD significantly ameliorated apoptosis of splenic T lymphocytes. Key proteins and factors in the AIM2/IL-1β/FasL/Fas axis are effectively inhibited from expression after BYHWD treatment.

CONCLUSION

It is the first study to demonstrate that BYHWD can improve stroke-induced immunosuppression by down-regulating Fas-dependent splenic T-cell apoptosis triggered by peripheral AIM2 inflammasome-driven signaling cascade.

IL-33/ST2 signaling in monocyte-derived macrophages maintains blood-brain barrier integrity and restricts infarctions early after ischemic stroke

BACKGROUND

Brain microglia and infiltrating monocyte-derived macrophages are vital in preserving blood vessel integrity after stroke. Understanding mechanisms that induce immune cells to adopt vascular-protective phenotypes may hasten the development of stroke treatments. IL-33 is a potent chemokine released from damaged cells, such as CNS glia after stroke. The activation of IL-33/ST2 signaling has been shown to promote neuronal viability and white matter integrity after ischemic stroke. The impact of IL-33/ST2 on blood-brain barrier (BBB) integrity, however, remains unknown. The current study fills this gap and reveals a critical role of IL-33/ST2 signaling in macrophage-mediated BBB protection after stroke.

METHODS

Transient middle cerebral artery occlusion (tMCAO) was performed to induce ischemic stroke in wildtype (WT) versus ST2 knockout (KO) male mice. IL-33 was applied intranasally to tMCAO mice with or without dietary PLX5622 to deplete microglia/macrophages. ST2 KO versus WT bone marrow or macrophage cell transplantations were used to test the involvement of ST2+ macrophages in BBB integrity. Macrophages were cocultured in transwells with brain endothelial cells (ECs) after oxygen-glucose deprivation (OGD) to test potential direct effects of IL33-treated macrophages on the BBB in vitro.

RESULTS

The ST2 receptor was expressed in brain ECs, microglia, and infiltrating macrophages. Global KO of ST2 led to more IgG extravasation and loss of ZO-1 in cerebral microvessels 3 days post-tMCAO. Intranasal IL-33 administration reduced BBB leakage and infarct severity in microglia/macrophage competent mice, but not in microglia/macrophage depleted mice. Worse BBB injury was observed after tMCAO in chimeric WT mice reconstituted with ST2 KO bone marrow, and in WT mice whose monocytes were replaced by ST2 KO monocytes. Macrophages treated with IL-33 reduced in vitro barrier leakage and maintained tight junction integrity after OGD. In contrast, IL-33 exerted minimal direct effects on the endothelial barrier in the absence of macrophages. IL-33-treated macrophages demonstrated transcriptional upregulation of an array of protective factors, suggesting a shift towards favorable phenotypes.

CONCLUSION

Our results demonstrate that early-stage IL-33/ST2 signaling in infiltrating macrophages reduces the extent of acute BBB disruption after stroke. Intranasal IL-33 administration may represent a new strategy to reduce BBB leakage and infarct severity.

RiboTag RNA Sequencing Identifies Local Translation of HSP70 In Astrocyte Endfeet After Cerebral Ischemia

Brain ischemia causes disruption in cerebral blood flow and blood-brain barrier (BBB) integrity which are normally maintained by the astrocyte endfeet. Emerging evidence points to dysregulation of the astrocyte translatome during ischemia, but its effects on the endfoot translatome are unknown. In this study, we aimed to investigate the early effects of ischemia on the astrocyte endfoot translatome in a rodent model of cerebral ischemia-reperfusion. To do so, we immunoprecipitated astrocyte-specific tagged ribosomes (RiboTag IP) from mechanically isolated brain microvessels. In mice subjected to middle cerebral artery occlusion and reperfusion and contralateral controls, we sequenced ribosome-bound RNAs from perivascular astrocyte endfeet and identified 205 genes that were differentially expressed in the translatome after ischemia. Pathways associated with the differential expressions included proteostasis, inflammation, cell cycle, and metabolism. Transcription factors whose targets were enriched amongst upregulated translating genes included HSF1, the master regulator of the heat shock response. The most highly upregulated genes in the translatome were HSF1-dependent Hspa1a and Hspa1b , which encode the inducible HSP70. We found that HSP70 is upregulated in astrocyte endfeet after ischemia, coinciding with an increase in ubiquitination across the proteome. These findings suggest a robust proteostasis response to proteotoxic stress in the endfoot translatome after ischemia. Modulating proteostasis in endfeet may be a strategy to preserve endfeet function and BBB integrity after ischemic stroke.

Association between neutrophil-to-lymphocyte ratio and short-term all-cause mortality in patients with cerebrovascular disease admitted to the intensive care unit-a study based on the MIMIC-IV database

Background

Inflammation plays a crucial role in cerebrovascular disease (CVD) progression. Neutrophil-to-lymphocyte ratio (NLR) is an important inflammatory marker, though its diagnostic role in CVD is still under investigation. This study evaluates the relationship between NLR and short-term all-cause mortality in patients with CVD admitted to the intensive care unit (ICU).

Methods

We conducted a retrospective study using data from the Medical Information Mart for Intensive Care (MIMIC-IV) (v2.2) database, including 4,327 adult ICU-admitted CVD patients. NLR values at admission were analyzed alongside various mortality variables. Multivariate Cox proportional hazards regression models and Kaplan-Meier (K-M) survival curves assessed the relationship between NLR and short-term all-cause mortality. Predictive power, sensitivity, specificity, and area under the curve (AUC) of NLR for short-term mortality were investigated using Receiver Operating Characteristic (ROC) analysis. Additionally, restricted cubic spline (RCS) curves and subgroup analyses were conducted.

Results

Among the 4,327 patients, 3,600 survived (survival group) and 727 died (non-survival group) within 28 days of admission (mortality rate: 16.8%). A multivariate Cox regression analysis identified NLR as an independent predictor of 28-day all-cause mortality (hazard ratio: 1.013; 95% confidence interval: 1.0086-1.0188; p < 0.001). The predictive model, incorporating NLR, age, gender, BMI, Charlson comorbidity index (CCI), WBC counts, Platelet, INR, and CRP, achieved an AUC of 0.686 (95% confidence interval: 0.665-0.70). While platelet-to-lymphocyte ratio was also analyzed, its predictive efficiency was less pronounced compared to NLR. A best NLR threshold of 6.19 was determined, distinguishing survivors from non-survivors. Kaplan-Meier survival curves showed that patients with NLR ≥ 6.19 had significantly lower survival rates at 7-, 14-, 21-, and 28-days. Subgroup analyses indicated that NLR did not significantly interact with most subgroups.

Conclusion

NLR may serve as an independent predictor for short-term all-cause mortality in ICU-admitted CVD patients, enhancing our understanding of the association between inflammatory biomarkers and CVD prognosis.

Role of transcription factors, noncoding RNAs, epitranscriptomics, and epigenetics in post-ischemic neuroinflammation

Post-stroke neuroinflammation is pivotal in brain repair, yet persistent inflammation can aggravate ischemic brain damage and hamper recovery. Following stroke, specific molecules released from brain cells attract and activate central and peripheral immune cells. These immune cells subsequently release diverse inflammatory molecules within the ischemic brain, initiating a sequence of events, including activation of transcription factors in different brain cell types that modulate gene expression and influence outcomes; the interactive action of various noncoding RNAs (ncRNAs) to regulate multiple biological processes including inflammation, epitranscriptomic RNA modification that controls RNA processing, stability, and translation; and epigenetic changes including DNA methylation, hydroxymethylation, and histone modifications crucial in managing the genic response to stroke. Interactions among these events further affect post-stroke inflammation and shape the depth of ischemic brain damage and functional outcomes. We highlighted these aspects of neuroinflammation in this review and postulate that deciphering these mechanisms is pivotal for identifying therapeutic targets to alleviate post-stroke dysfunction and enhance recovery.

Jun-activated SOCS1 enhances ubiquitination and degradation of CCAAT/enhancer-binding protein β to ameliorate cerebral ischaemia/reperfusion injury

This study investigates the molecular mechanisms behind ischaemia/reperfusion (I/R) injury in the brain, focusing on neuronal apoptosis. It scrutinizes the role of the Jun proto-oncogene in apoptosis, involvement of SOCS1 in neural precursor cell accumulation in ischaemic regions, and the upregulation of C-EBPβ in the hippocampus following I/R. Key to the study is understanding how Jun controls C-EBPβ degradation via SOCS1, potentially offering new clinical treatment avenues for I/R. Techniques such as mRNA sequencing, KEGG enrichment analysis and protein-protein interaction (PPI) in mouse models have indicated involvement of Jun (AP-1) in I/R-induced cerebral damage. The study employs middle cerebral artery occlusion in different mouse models and oxygen-glucose deprivation/reoxygenation in cortical neurons to examine the impacts of Jun and SOCS1 manipulation on cerebral I/R injury and neuronal damage. The findings reveal that I/R reduces Jun expression in the brain, but its restoration lessens cerebral I/R injury and neuron death. Jun activates SOCS1 transcriptionally, leading to C-EBPβ degradation, thereby diminishing cerebral I/R injury through the SOCS1/C-EBPβ pathway. These insights provide a deeper understanding of post-I/R cerebral injury mechanisms and suggest new therapeutic targets for cerebral I/R injury. KEY POINTS: Jun and SOCS1 are poorly expressed, and C-EBPβ is highly expressed in ischaemia/reperfusion mouse brain tissues. Jun transcriptionally activates SOCS1. SOCS1 promotes the ubiquitination-dependent C-EBPβ protein degradation. Jun blunts oxygen-glucose deprivation/reoxygenation-induced neuron apoptosis and alleviates neuronal injury. This study provides a theoretical basis for the management of post-I/R brain injury.