Modulation of NLRP3 inflammasome-related-inflammation via RIPK1/RIPK3-DRP1 or HIF-1α signaling by phenothiazine in hypothermic and normothermic neuroprotection after acute ischemic stroke.

BACKGROUND: Inflammation and subsequent mitochondrial dysfunction and cell death worsen outcomes after revascularization in ischemic stroke. Receptor-interacting protein kinase 1 (RIPK1) activated dynamin-related protein 1 (DRP1) in a NLRPyrin domain containing 3 (NLRP3) inflammasome-dependent fashion and Hypoxia-Inducible Factor (HIF)-1α play key roles in the process. This study determined how phenothiazine drugs (chlorpromazine and promethazine (C + P)) with the hypothermic and normothermic modality impacts the RIPK1/RIPK3-DRP1 and HIF-1α pathways in providing neuroprotection. METHODS: A total of 150 adult male Sprague-Dawley rats were subjected to 2 h middle cerebral artery occlusion (MCAO) followed by 24 h reperfusion. 8 mg/kg of C + P was administered at onset of reperfusion. Infarct volumes, mRNA and protein expressions of HIF-1α, RIPK1, RIPK3, DRP-1, NLRP3-inflammation and cytochrome c-apoptosis were assessed. Apoptotic cell death, infiltration of neutrophils and macrophages, and mitochondrial function were evaluated. Interaction between RIPK1/RIPK3 and HIF-1α/NLRP3 were determined. In SH-SY5Y cells subjected to oxygen/glucose deprivation (OGD), the normothermic effect of C + P on inflammation and apoptosis were examined. RESULTS: C + P significantly reduced infarct volumes, mitochondrial dysfunction (ATP and ROS concentration, citrate synthase and ATPase activity), inflammation and apoptosis with and without induced hypothermia. Overexpression of RIPK1, RIPK3, DRP-1, NLRP3-inflammasome and cytochrome c-apoptosis were all significantly reduced by C + P at 33 °C and the RIPK1 inhibitor (Nec1s), suggesting hypothermic effect of C + P via RIPK1/RIPK3-DRP1pathway. When body temperature was maintained at 37 °C, C + P and HIF-1α inhibitor (YC-1) reduced HIF-1α expression, leading to reduction in mitochondrial dysfunction, NLRP3 inflammasome and cytochrome c-apoptosis, as well as the interaction of HIF-1α and NLRP3. These were also evidenced in vitro, indicating a normothermic effect of C + P via HIF-1α. CONCLUSION: Hypothermic and normothermic neuroprotection of C + P involve different pathways. The normothermic effect was mediated by HIF-1α, while hypothermic effect was via RIPK1/RIPK3-DRP1 signaling. This provides a theoretical basis for future precise exploration of hypothermic and normothermic neuroprotection.

Rapid Intravenous Glyceryl Trinitrate in Ischemic Damage (RIGID): A potential neuroprotection strategy for acute ischemic stroke (AIS) patients.

Despite advances in intravenous thrombolysis and endovascular thrombectomy, numerous acute ischemic stroke survivors continue to experience various disability levels. The nitric oxide (NO) donor, Glyceryl Trinitrate (GTN), has been identified as a potential neuroprotective agent against ischemic damage. We evaluated the safety and feasibility of intravenous GTN in AIS patients. Subsequently, we conducted a secondary analysis to assess for possible efficacy of GTN as a neuroprotectant. We conducted a prospective, double-blind, randomized controlled trial in the Stroke Intervention & Translational Center (SITC) in Beijing Luhe Hospital, Capital Medical University (ChiCTR2100046271). AIS patients within 24 h of stroke onset were evenly divided into GTN or control groups (n = 20 each). The GTN group received intravenous GTN (5 mg in 50 ml saline at a rate of 0.4 mg/h for 12.5 h/day over 2 days), while controls were administered an equivalent volume of 0.9% saline. Both groups followed standard Stroke Guidelines for treatment. Safety measures focused on SBP<110 mmHg and headache occurrence. Efficacy was assessed via the 90-day modified rankin score (mRS) and the national institutes of health stroke score (NIHSS). Of the 40 AIS patients, baseline characteristics such as age, gender, risk factors, and pre-mRS scores showed no significant difference between the groups. Safety measures of SBP<110 mmHg and headache occurrence were comparable. Overall, 90-day mRS (1 vs. 1) and NIHSS (1 vs. 1) did not significantly differ between groups. However, the GTN-treated group had a benefit in enhancing NIHSS recovery (△NIHSS 4.5 vs. 3, p = 0.028), indicating that GTN may augment recovery. Subgroup analyses revealed a benefit in the GTN group at the 90-day NIHSS score and △NIHSS follow up for non-thrombolysis patients (1 vs. 2, p = 0.016; 5 vs. 2, p = 0.001). Moreover, the GTN group may benefit mild stroke patients in NIHSS score at 90 day and △NIHSS observed at 90 days (1 vs. 1, p = 0.025; 3 vs. 2 p = 0.002). Overall, while preliminary data suggest GTN might aid recovery in NIHSS improvement, the evidence is tempered due to sample size limitations. The RIGID study confirms the safety and feasibility of intravenous GTN administration for AIS patients. Preliminary data also suggest that the GTN group may provide improvement in NIHSS recovery compared to the control group. Furthermore, a potential benefit for non-thrombolysis patients and those with mild stroke symptoms was identified, suggesting a possible potential role as a tailored intervention in specific AIS subgroups. Due to the limited sample size, further larger RCT will be necessary to replicate these results. TRIAL REGISTRATION: www.chictr.org.cn, identifier: ChiCTR2100046271.

Exploring the Therapeutic Potential of Peritoneal Dialysis (PD) in the Treatment of Neurological Disorders.

Peritoneal dialysis (PD) is a well-established renal replacement therapy commonly employed in clinical practice. While its primary application is in the treatment of kidney disease, its potential in addressing other systemic disorders, including neurological diseases, has garnered increasing interest. This study provides a comprehensive overview of the related technologies, unique advantages, and clinical applications of PD in the context of neurological disorders. By exploring the mechanism underlying PD, its application in neurological diseases, and associated complications, we addressed the feasibility and benefits of PD as an adjunct therapy for various neurological conditions. Our study aims to highlight its role in detoxification and symptom management, as well as its advantages over other universally accepted methods of renal replacement therapy. Our goal is to bring to the spotlight the therapeutic potential of PD in neurological diseases, such as stroke, stimulate further research, and broaden the scope of its application in the clinical setting.

Post-stroke dizziness, depression and anxiety.

OBJECTIVE: Vestibular and psychiatric disorders are very closely related. Previous research shows that the discomfort and dysfunction caused by dizziness in patients can affect psychological processes, leading to anxiety and depression, and the irritation of anxiety and depression can aggravate the discomfort of dizziness. But the causal relationship between dizziness in the recovery period of stroke and Post-stroke depression (PSD) / Post-stroke anxiety (PSA) is not clear. Identifying the causal relationship between them can enable us to conduct more targeted treatments. METHODS: We review the epidemiology and relationship of dizziness, anxiety, and depression, along with the related neuroanatomical basis. We also review the pathophysiology of dizziness after stroke, vestibular function of patients experiencing dizziness, and the causes and mechanisms of PSD and PSA. We attempt to explore the possible relationship between post-stroke dizziness and PSD and PSA. CONCLUSION: The treatment approach for post-stroke dizziness depends on its underlying cause. If the dizziness is a result of PSD and PSA, addressing these psychological factors may alleviate the dizziness. This can be achieved through targeted treatments for PSD and PSA, such as psychotherapy, antidepressants, or anxiolytics, which could indirectly improve dizziness symptoms. Conversely, if PSA and PSD are secondary to vestibular dysfunction caused by stroke, a thorough vestibular function assessment is crucial. Identifying the extent of vestibular impairment allows for tailored interventions. These could include vestibular rehabilitation therapy and medication aimed at vestibular restoration. By improving vestibular function, secondary symptoms like anxiety and depression may also be mitigated.

The Greater Omentum: Multifaceted Interactions in Neurological Recovery and Disease Progression.

The greater omentum, a unique anatomical structure composed of adipocytes, loose connective tissue, and a dense vascular network. Plays a pivotal role beyond its traditional understanding. It houses specialized immunological units known as 'Milky spots,' making it a key player in immune response. Moreover, the omentum's capacity to enhance tissue perfusion, absorb edema fluid, boost acetylcholine synthesis, and foster neuron repair have rendered it a topic of interest in the context of various diseases, especially neurological disorders. This review provides a comprehensive overview of the intricate anatomy and histology of the greater omentum, casting light on its multifaceted functions and its associations with a spectrum of diseases. With a specific focus on neurological ailments, we delineate the intricate relationship that the omentum shares with other pathologies like stroke and we underly its contribution to serving as a therapeutic agent in neurological disorders. By deciphering the underlying mechanisms and emphasizing areas that demand further investigation. This review aims to spark renewed interest and pave the way for comprehensive studies exploring the greater omentum's potential in neurology and broader medicine overall. Given these diverse interactions that yet remain elusive, we must investigate and understand the nuanced relationship between the greater omentum and pathologies, especially its role in stroke's pathophysiology and therapeutic interventions so as to enhance patient care.

The Modulatory Role of Hypothermia in Post-Stroke Brain Inflammation: Mechanisms and Clinical Implications.

BACKGROUND: Acute ischemic stroke remains a major contributor to mortality and disability worldwide. The use of hypothermia has emerged as a promising neuroprotective strategy, with proven effectiveness in cardiac arrest and neonatal hypoxic-ischemic injury. SUMMARY: This review explores the therapeutic potential of hypothermia in ischemic stroke by examining its impact on post-stroke inflammatory responses. We synthesized evidence from basic and clinical studies to illustrate the inhibitory effects of hypothermia on post-stroke brain inflammation. The underlying mechanisms include modulation of microglial activation and polarization, downregulation of key inflammatory pathways such as MAPKs, NF-KB, and JAK/STAT, protection of the blood-brain barrier integrity, and reduction of immune cell infiltration into the brain. We also discuss the current limitations of hypothermia treatment in clinical practice and highlight future research directions for optimizing protocols and evaluating its clinical efficacy in stroke patients. KEY MESSAGES: Therapeutic hypothermia (TH) has evolved significantly with advancements in medical technologies, especially with the introduction of automated cooling devices, both intravascular and surface based. However, a refined, highly individualized and effective hypothermia protocol may stand robust against the devastating consequences of ischemic stroke, and we think it should become the future development goal.

A novel stroke rehabilitation strategy and underlying stress granule regulations through inhibition of NLRP3 inflammasome activation.

OBJECTIVE: Dynamic changes in ischemic pathology after stroke suggested a "critical window" of enhanced neuroplasticity immediately after stroke onset. Although physical exercise has long been considered a promising strategy of stroke rehabilitation, very early physical exercise may exacerbate brain injury. Since remote ischemic conditioning (RIC) promotes neuroprotection and neuroplasticity, the present study combined RIC with sequential exercise to establish a new rehabilitation strategy for a better rehabilitative outcome. METHODS: A total of 120 adult male Sprague-Dawley rats were used and divided into five groups: (1) sham, (2) stroke, (3) stroke with exercise, (4) stroke with RIC, and (5) stroke with RIC followed by exercise. Brain damage was evaluated by infarct volume, neurological deficit, cell death, and lactate dehydrogenase (LDH) activity. Long-term functional outcomes were determined by grid walk tests, rotarod tests, beam balance tests, forelimb placing tests, and the Morris water maze. Neuroplasticity was evaluated through measurements of both mRNA and protein levels of synaptogenesis (synaptophysin [SYN], post-synaptic density protein-95 [PSD-95], and brain-derived neurotrophic factor [BDNF]) and angiogenesis (vascular endothelial growth factor [VEGF], angiopoietin-1 [Ang-1], and angiopoietin-2 [Ang-2]). Inflammasome activation was measured by concentrations of interleukin-18 (IL-18) and IL-1ß detected by enzyme-linked immunosorbent assay (ELISA) kits, mRNA expressions of NLR pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain (ASC), IL-18 and IL-1ß, and protein quantities of NLRP3, ASC, cleaved-caspase-1, gasdermin D-N (GSDMD-N), and IL-18 and IL-1ß. Stress granules (SGs), including GTPase-activating protein-binding protein 1 (G3BP1), T cell-restricted intracellular antigen-1 (TIA1), and DEAD-box RNA helicase 3X (DDX3X) were evaluated at mRNA and protein levels. The interactions between DDX3X with NLRP3 or G3BP1 were determined by immunofluorescence and co-immunoprecipitation. RESULTS: Early RIC decreased infarct volumes, neurological deficits, cell death, and LDH activity at post-stroke Day 3 (p < 0.05). All treatment groups showed significant improvement in functional outcomes, including sensory, motor, and cognitive functions. RIC and exercise, as compared to RIC or physical exercise alone, had improved functional outcomes after stroke (p < 0.05), as well as synaptogenesis and angiogenesis (p < 0.05). RIC significantly reduced mRNA and protein expressions of NLRP3 (p < 0.05). SGs formation peaked at 0 h after ischemia, then progressively decreased until 24 h postreperfusion, which was reversed by RIC (p < 0.05). The assembly of SGs consumed DDX3X and then inhibited NLRP3 inflammasome activation. CONCLUSIONS: RIC followed by exercise induced a better rehabilitation in ischemic rats, while early RIC alleviated ischemia-reperfusion injury via stress-granule-mediated inhibition of NLRP3 inflammasome.

Association of Early Longitudinal Changes in the Neutrophil-to-Lymphocyte Ratio With Adverse Clinical Outcomes in Acute Ischemic Stroke Patients After Endovascular Treatment.

BACKGROUND: We aim to elucidate the contribution of early dynamic changes in the neutrophil-to-lymphocyte ratio (NLR) to poor clinical outcomes in acute ischemic stroke patients after endovascular treatment (EVT). METHODS: Acute ischemic stroke patients who underwent EVT were consecutively recruited from January 2019 to July 2022. Blood cell counts were sampled at admission and at following 24 hours after EVT. Clinical outcome measures included 3-month functional dependence (modified Rankin scale of 3-6), symptomatic intracranial hemorrhage, and mortality at 7 days and 30 days. Multinomial logistic regressions were used to evaluate the association of changes in the NLR with unfavorable outcomes. RESULTS: A total of 590 patients were included in the final analysis. The multinomial logistic model indicated that the increasing changes in the NLR after EVT was an independent factor for poor outcomes; the adjusted odds ratio was 1.06 (95% confidence interval [CI] 1.03-1.10; P < 0.001) at poor 3-month functional outcomes, 1.07 (95% CI 1.04-1.10; P < 0.001) at symptomatic intracranial hemorrhage, 1.08 (95% CI 1.05-1.12; P < 0.001) at mortality at 7 days, and 1.04 (95% CI 1.02-1.07; P = 0.001) at mortality at 30 days. Areas under the curve of changes in NLR to discriminate adverse outcomes were 0.725, 0.687, 0.664, and 0.659, respectively. The optimal cutoff values were 5.77 (56.6% sensitivity, 81.0% specificity), 6.92 (60.0% sensitivity, 77.0% specificity), 8.64 (51.0% sensitivity, 82.0% specificity), and 8.64 (48.7% sensitivity, 83.0% specificity), respectively. CONCLUSIONS: The NLR in acute ischemic stroke patients increased remarkably independent of successful reperfusion. Elevated changes in the NLR might predict malignant hemorrhagic transformation, adverse functional outcomes, and short-term mortality.

Prevalence and Impact of Medical Complications on Clinical Outcomes in Acute Ischemic Stroke Patients After Endovascular Therapy - Data From a Comprehensive Stroke Unit in China.

OBJECTIVE: We aim to assess the incidence and impact of in-hospital medical complications (MCs) on clinical outcomes in acute ischemic stroke (AIS) patients after endovascular therapy (EVT). METHODS: AIS patients who underwent EVT were consecutively recruited from January 2019 to July 2022. The primary outcome was a poor 3-month functional outcome, defined as a modified Rankin Scale score (mRS) of 3-6. The safety variables were symptomatic intracerebral hemorrhage and mortality at 7 and 30 days. RESULTS: A total of 306 (50.1%) patients experienced at least one of the MCs. The most common MC was pneumonia (42.6%). Multivariate analysis revealed that the setting of MCs was an independent predictor of a poor 3-month functional outcome (adjusted odds ratio [aOR] 4.40, 95% confidence interval [CI] 3.01-6.42; P < 0.001). In the subgroup analysis, this trend was significant, especially in the patients aged 60-75 years (aOR 5.87, 95% CI 3.45-9.97; P < 0.001) or with baseline NIHSS (≤16) (aOR 5.05, 95% CI 2.84-9.01; P < 0.001). For individuals, cardiac events (aOR 8.56, 95% CI 4.05-18.09; P < 0.001), pneumonia (aOR 5.08, 95% CI 3.42-7.55; P < 0.001), and gastrointestinal bleeding (GIB) (aOR 6.12, 95% CI 3.40-11.01; P < 0.001) were independently associated with the poor 3-month outcome. The setting of MCs was independently associated with symptomatic intracerebral hemorrhage (aOR 2.11, 95% CI 1.22-3.64; P = 0.007) and mortality at 30 days (aOR 2.11, 95% CI 1.22-3.64; P = 0.007) after adjustment, but not with mortality at 7 days. CONCLUSIONS: MCs in AIS patients after EVT have a high incidence, despite successful reperfusion, adversely affecting clinical outcomes and increasing short-term mortality.

Vestibular function is associated with immune inflammatory response.

Association between vestibular function and immune inflammatory response has garnered increasing interest. Immune responses can lead to anatomical or functional alterations of the vestibular system, and inflammatory reactions may impair hearing and balance. Vestibular disorders comprise a variety of conditions, such as vestibular neuritis, benign paroxysmal positional vertigo, Meniere's disease, vestibular migraine, posterior circulation ischemia, and bilateral vestibular disease. Moreover, some patients with autoimmune diseases develop vestibulocochlear symptom. This paper offers an overview of prevalent vestibular diseases and discusses associations between vestibular dysfunction and immune diseases.

Arterial Glyceryl Trinitrate in Acute Ischemic Stroke After Thrombectomy for Neuroprotection (AGAIN): A Pilot Randomized Controlled Trial.

Although endovascular therapy demonstrates robust clinical efficacy in acute ischemic stroke (AIS), not all stroke patients benefit from successful reperfusion. This study aimed to evaluate the safety, feasibility, and preliminary efficacy of intra-arterial administration of glyceryl trinitrate (GTN) after endovascular recanalization for neuroprotection. This is a prospective randomized controlled study. Eligible patients were randomized to receive 800 µg GTN or the same volume of normal saline through the catheter after recanalization. The primary outcome was symptomatic intracranial hemorrhage (ICH), while secondary outcomes included mortality, functional outcome, infarction volume, complications, and blood nitrate index (NOx). A total of 40 patients were enrolled and randomized with no participants being lost to follow-up. There was no significant difference in the proportion of sICH between GTN and control groups. Additionally, no significant difference was observed in mortality or rates of neurological deterioration and other complications. Favorable trends, while non-significant, were noted in both outcome and imaging for functional independence at 90 days and reduction in final infarct volume (75.0% vs 65.0%; 33.2 vs 38.9 ml) for the GTN group. Moreover, the concentration of blood NOx in the GTN group was significantly higher than in the control group at 2 h after GTN administration (26.2 vs 18.0 µmol/l, p < 0.05). The AGAIN study suggests intra-arterial administration of GTN post-endovascular therapy is safe and feasible and GTN successfully raised NOx levels over controls at 2 h. A multi-center randomized controlled trial with a larger sample size is warranted to determine GTN neoadjuvant efficacy.

Phenothiazines reduced autophagy in ischemic stroke through endoplasmic reticulum (ER) stress-associated PERK-eIF2α pathway.

BACKGROUND: Neuroprotective effects have been the main focus of new treatment modalities for ischemic stroke. Phenothiazines, or chlorpromazine plus promethazine (C + P), are known to prevent the generation of free radicals and uptake of Ca2+ by plasma membrane; they have a potential as a treatment for acute ischemic stroke (AIS). This study aims to investigate the role of endoplasmic reticulum (ER) stress-associated PERK-eIF2α pathway underlying the phenothiazine-induced neuroprotective effects after cerebral ischemia/reperfusion (I/R) injury. METHODS: A total of 49 male Sprague Dawley rats (280-320 g) were randomly divided into 4 groups (n = 7 per group): (1) sham, (2) I/R that received 2 h of middle cerebral artery occlusion (MCAO), followed by 6 or 24 h of reperfusion, (3) MCAO treated by C + P without temperature control and (4) MCAO treated by C + P with temperature control. Human neuroblastoma (SH-SY5Y) cells were used in 5 groups: (1) control, (2) oxygen-glucose deprivation (OGD) for 2 h followed by reoxygenation (OGD/R), (3) OGD/R with C + P; (4) OGD/R with PERK inhibitor, GSK2656157, and (5) OGD/R with C + P and GSK2656157. The molecules of ER stress, unfolded protein response (UPR) (Bip, PERK, p-PERK, p-PERK/PERK, eIF2α, p-eIF2α, p-eIF2α/eIF2α), autophagy (ATG12, LC3II/I), and apoptosis (BAX, Bcl-XL) were measured at mRNA levels by real time PCR and protein levels by Western blotting. RESULTS: In ischemic rats followed by reperfusion, expression of Bip, p-PERK/PERK, p-eIF2α/eIF2α, ATG12, and LC3II/I, as well as BAX were all significantly increased. These markers were significantly reduced by C + P at both 6 and 24 h of reperfusion. Anti-apoptotic Bcl-XL expression was increased, while pro-apoptotic BAX expression was decreased by C + P. In SH-SY5Y cell lines, both C + P and GSK2656157 significantly reduced the level of autophagy and apoptosis after I/R, respectively. The combination of GSK2656157 and C + P did not promote the same effect, suggesting that C + P did not induce any neuroprotective effect by inhibiting autophagy and apoptosis through the PERK-eIF2α pathway when this pathway was already blocked by GSK2656157. In general, the reduction in body temperature by phenothiazines was associated with better neuroprotection but it did not reach significant levels. CONCLUSION: The combined treatment of C + P plays a crucial role in stroke therapy by inhibiting ER stress-mediated autophagy, thereby leading to reduced apoptosis and increased neuroprotection. Our findings highlight the PERK-eIF2α pathway as a central mechanism through which C + P exerts its beneficial effects. The results from this study may pave the way for the development of more targeted and effective treatments for stroke patients.

Hepatic responses following acute ischemic stroke: A clinical research update.

Acute ischemic stroke (AIS) not only affects the brain but also has significant implications for peripheral organs through neuroendocrine regulation. This reciprocal relationship influences overall brain function and stroke prognosis. Recent research has highlighted the importance of poststroke liver changes in determining patient outcomes. In our previous study, we investigated the relationship between stroke and liver function. Our findings revealed that the prognostic impact of stress-induced hyperglycemia in patients undergoing acute endovascular treatment for acute large vessel occlusion is closely related to their preexisting diabetes status. We found that the liver contributes to stress hyperglycemia after AIS by increasing hepatic gluconeogenesis and decreasing hepatic insulin sensitivity. These changes are detrimental to the brain, particularly in patients without diabetes. Furthermore, we examined the role of bilirubin, a byproduct of hepatic hemoglobin metabolism, in stroke pathophysiology. Our results demonstrated that blood bilirubin levels can serve as predictors of stroke severity and may hold therapeutic potential for reducing oxidative stress-induced stroke injury in patients with mild stroke. These results underscore the potential role of the liver in the oxidative stress response following AIS, paving the way for further investigation into liver-targeted therapeutic strategies to improve stroke prognosis and patient outcomes.

Montelukast sodium protects against focal cerebral ischemic injury by regulating inflammatory reaction via promoting microglia polarization.

BACKGROUND: Neuroinflammation plays an important role in brain injury and repair. Regulation of post-stroke inflammation may be a reasonable strategy to treat ischemic stroke. The present study demonstrates that montelukast sodium protected brain tissue by regulating the post-stroke inflammatory reaction. METHODS: Adult male mice underwent distal occlusion of the middle cerebral artery (d-MCAO) surgery, followed by intraperitoneal injection of montelukast sodium or equivalent saline, from day 0-7 after the operation. On the 7th day, Rotarod and adhesive-removal test were performed. M AP2 staining, and Iba1, CD206, and CD16/32 co staining were performed. BV2 microglial cell lines were co-cultured with different concentrations of montelukast sodium with or without lipopolysaccharide (LPS). Real-time polymerase chain reaction (rt-PCR) and enzyme linked immunosorbent assay (ELISA) were used to detect the mRNA expression of M1 and M2 phenotypic microglia markers and the release of cytokines representing from different phenotypes of microglia cells. RESULTS: Montelukast sodium prolonged the time that d-MCAO mice remained on the rotating bar, shortened the time to remove the sticker on the opposite claw, and reduced the infarct volume, promoting the transformation of microglial cells/macrophages around the infarct to the M2 phenotype. Montelukast sodium increased the mRNA expression of Arg-1, CD206, TGF-ß, and IL-10 in BV2 microglial cell lines stimulated by LPS, while decreased the expression of iNOS, TNF-α, and CD16/32. CONCLUSION: Montelukast sodium can protect against focal cerebral ischemic injury by regulating inflammatory reaction via promoting microglia polarization.

Cerebral Glucose Metabolism and Potential Effects on Endoplasmic Reticulum Stress in Stroke.

Ischemic stroke is an extremely common pathology with strikingly high morbidity and mortality rates. The endoplasmic reticulum (ER) is the primary organelle responsible for conducting protein synthesis and trafficking as well as preserving intracellular Ca2+ homeostasis. Mounting evidence shows that ER stress contributes to stroke pathophysiology. Moreover, insufficient circulation to the brain after stroke causes suppression of ATP production. Glucose metabolism disorder is an important pathological process after stroke. Here, we discuss the relationship between ER stress and stroke and treatment and intervention of ER stress after stroke. We also discuss the role of glucose metabolism, particularly glycolysis and gluconeogenesis, post-stroke. Based on recent studies, we speculate about the potential relationship and crosstalk between glucose metabolism and ER stress. In conclusion, we describe ER stress, glycolysis, and gluconeogenesis in the context of stroke and explore how the interplay between ER stress and glucose metabolism contributes to the pathophysiology of stroke.

Vertebrobasilar artery cooling infusion in acute ischemic stroke for posterior circulation following thrombectomy: Rationale, design and protocol for a prospective randomized controlled trial.

Background: Although endovascular mechanical thrombectomy demonstrates clinical efficacy in posterior circulation acute ischemic stroke (AIS), only one third of these patients attain functional independence with a third of patients' expiring despite vascular recanalization. Neuroprotection strategies, such as therapeutic hypothermia (TH) have been considered a promising adjunctive treatment in AIS. We propose the following rationale, design and protocol for a prospective randomized controlled trial (RCT) aimed to determine whether Vertebrobasilar Artery Cooling Infusion (VACI) improves functional outcomes in posterior circulation AIS patients post mechanical thrombectomy. Methods: Subjects in the study will be assigned randomly to either the cooling infusion or the control group in a 1:1 ratio (n = 40). Patients allocated to the cooling infusion group will receive 300 ml cool saline at 4C through the catheter (30 ml/min) into vertebral artery after thrombectomy. The control group will receive the same volume of 37C saline. All patients enrolled will receive standard care according to current guidelines for stroke management. The primary outcome is symptomatic intracranial hemorrhage (ICH), whereas the secondary outcomes include functional outcome score, infarction volume, mortality, ICH, fatal ICH, cerebral vasospasm, coagulation abnormality, pneumonia and urinary infection. Discussions: This study will determine the preliminary safety, feasibility, and neuroprotective benefits of VACI in posterior circulation AIS patients with reperfusion therapy. The results of this study may provide evidence for VACI as a new therapy in posterior circulation AIS. Clinical Trial Registration: www.chictr.org.cn, ChiCTR2200065806, registered on November 15, 2022.

Large vessel occlusion stroke outcomes in diabetic vs. non-diabetic patients with acute stress hyperglycemia.

Objective: This study assesses whether stress-induced hyperglycemia is a predictor of poor outcome at 3 months for patients with acute ischemic stroke (AIS) treated by endovascular treatment (EVT) and impacted by their previous blood glucose status. Methods: This retrospective study collected data from 576 patients with AIS due to large vessel occlusion (LVO) treated by EVT from March 2019 to June 2022. The sample was composed of 230 and 346 patients with and without diabetes mellitus (DM), respectively, based on their premorbid diabetic status. Prognosis was assessed with modified Rankin Scale (mRS) at 3-month after AIS. Poor prognosis was defined as mRS>2. Stress-induced hyperglycemia was assessed by fasting glucose-to-glycated hemoglobin ratio (GAR). Each group was stratified into four groups by quartiles of GAR (Q1-Q4). Binary logistic regression analysis was used to identify relationship between different GAR quartiles and clinical outcome after EVT. Results: In DM group, a poor prognosis was seen in 122 (53%) patients and GAR level was 1.27 ± 0.44. These variables were higher than non-DM group and the differences were statistically significant (p < 0.05, respectively). Patients with severe stress-induced hyperglycemia demonstrated greater incidence of 3-month poor prognosis (DM: Q1, 39.7%; Q2, 45.6%; Q3, 58.6%; Q4, 68.4%; p = 0.009. Non-DM: Q1, 31%; Q2, 32.6%; Q3, 42.5%; Q4, 64%; p < 0.001). However, the highest quartile of GAR was independently associated with poor prognosis at 3 months (OR 3.39, 95% CI 1.66-6.96, p = 0.001), compared to the lowest quartile in non-DM patients after logistic regression. This association was not observed from DM patients. Conclusion: The outcome of patients with acute LVO stroke treated with EVT appears to be influenced by premorbid diabetes status. However, the poor prognosis at 3-month in patients with DM is not independently correlated with stress-induced hyperglycemia. This could be due to the long-term damage of persistent hyperglycemia and diabetic patients' adaptive response to stress following acute ischemic damage to the brain.

Induced Inflammatory and Oxidative Markers in Cerebral Microvasculature by Mentally Depressive Stress.

Background: Cerebrovascular disease (CVD) is recognized as the leading cause of permanent disability worldwide. Depressive disorders are associated with increased incidence of CVD. The goal of this study was to establish a chronic restraint stress (CRS) model for mice and examine the effect of stress on cerebrovascular inflammation and oxidative stress responses. Methods: A total of forty 6-week-old male C57BL/6J mice were randomly divided into the CRS and control groups. In the CRS group (n = 20), mice were placed in a well-ventilated Plexiglas tube for 6 hours per day for 28 consecutive days. On day 29, open field tests (OFT) and sucrose preference tests (SPT) were performed to assess depressive-like behaviors for the two groups (n = 10/group). Macrophage infiltration into the brain tissue upon stress was analyzed by measuring expression of macrophage marker (CD68) with immunofluorescence in both the CRS and control groups (n = 10/group). Cerebral microvasculature was isolated from the CRS and controls (n = 10/group). mRNA and protein expressions of tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-6 (IL-6), vascular cell adhesion molecule-1 (VCAM-1), and macrophage chemoattractant protein-1 (MCP-1) in the brain vessels were measured by real-time PCR and Western blot (n = 10/group). Reactive oxygen species (ROS), hydrogen peroxide (H2O2), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activities were quantified by ELISA to study the oxidative profile of the brain vessels (n = 10/group). Additionally, mRNA and protein expressions of NOX subunits (gp91phox, p47phox, p67phox, and p22phox) in the cerebrovascular endothelium were analyzed by real-time PCR and Western blot (n = 10/group). Results: CRS decreased the total distances (p < 0.05) and the time spent in the center zone in OFT (p < 0.001) and sucrose preference test ratio in SPT (p < 0.01). Positive ratio of CD68+ was increased with CRS in the entire region of the brain (p < 0.001), reflecting increased macrophage infiltration. CRS increased the expression of inflammatory factors and oxidative stress in the cerebral microvasculature, including TNF-α (p < 0.001), IL-1ß (p < 0.05), IL-6 (p < 0.05), VCAM-1 (p < 0.01), MCP-1 (p < 0.01), ROS (p < 0.001), and H2O2 (p < 0.001). NADPH oxidase (NOX) was activated by CRS (p < 0.01), and mRNA and protein expressions of NOX subunits (gp91phox, p47phox, p67phox, and p22phox) in brain microvasculature were found to be increased. Conclusions: To our knowledge, this is the first study to demonstrate that CRS induces depressive stress and causes inflammatory and oxidative stress responses in the brain microvasculature.

Exercise postconditioning reduces ischemic injury via suppression of cerebral gluconeogenesis in rats.

Pre-stroke exercise conditioning reduces neurovascular injury and improves functional outcomes after stroke. The goal of this study was to explore if post-stroke exercise conditioning (PostE) reduced brain injury and whether it was associated with the regulation of gluconeogenesis. Adult rats received 2 h of middle cerebral artery (MCA) occlusion, followed by 24 h of reperfusion. Treadmill activity was then initiated 24 h after reperfusion for PostE. The severity of the brain damage was determined by infarct volume, apoptotic cell death, and neurological deficit at one and three days after reperfusion. We measured gluconeogenesis including oxaloacetate (OAA), phosphoenolpyruvate (PEP), pyruvic acid, lactate, ROS, and glucose via ELISA, as well as the location and expression of the key enzyme phosphoenolpyruvate carboxykinase (PCK)-1/2 via immunofluorescence. We also determined upstream pathways including forkhead transcription factor (FoxO1), p-FoxO1, 3-kinase (PI3K)/Akt, and p-PI3K/Akt via Western blot. Additionally, the cytoplasmic expression of p-FoxO1 was detected by immunofluorescence. Compared to non-exercise control, PostE (*p < .05) decreased brain infarct volumes, neurological deficits, and cell death at one and three days. PostE groups (*p < .05) saw increases in OAA and decreases in PEP, pyruvic acid, lactate, ROS, glucose levels, and tissue PCKs expression on both days. PCK-1/2 expressions were also significantly (*p < .05) suppressed by the exercise setting. Additionally, phosphorylated PI3K, AKT, and FoxO1 protein expression were significantly induced by PostE at one and three days (*p < .05). In this study, PostE reduced brain injury after stroke, in association with activated PI3K/AKT/FoxO1 signaling, and inhibited gluconeogenesis. These results suggest the involvement of FoxO1 regulation of gluconeogenesis underlying post-stroke neuroprotection.

The Key Role of Initiation Timing on Stroke Rehabilitation by Remote Ischemic Conditioning with Exercise (RICE).

OBJECTIVE: Physical therapy is an integral part of post-stroke rehabilitation. Remote ischemic conditioning (RIC) induces neuroprotection within 24 hours after stroke, during which exercise is unsafe and ineffective. We combined RIC with exercise to establish a novel rehabilitation strategy, RICE (RIC+Exercise). The aim of this study was to optimize the RICE protocol in neurorehabilitation. METHODS: Thirty-two adult male Sprague-Dawley rats were placed in one of four groups: stroke with no rehabilitation or stroke with various RICE protocols. To further understand the mechanisms underlying neurorehabilitation, sixteen adult male Sprague-Dawley were added, each placed in one of two groups: stroke with exerciseor RIC  . Long-term functional outcomes were determined by beam balance, rota-rod, grid walk, forelimb placing, and Morris water maze tests up to 28 days after stroke (p < 0.05). Changes in neuroplasticity including synaptogenesis (assessed by measuring synaptophysin, post-synaptic density protein-95, and brain-derived neutrophic factor), angiogenesis (via vascular endothelial growth factor, Angiopoietin-1, and Angiopoietin-2), and regulatory molecules (including hypoxia inducible factor-1α, phospholipase D2 and the mechanistic target of rapamycin pathway), were all measured at both mRNA and protein levels (p < 0.05). RESULTS: All rehabilitation groups showed significant improvement in functional outcomes and levels of synaptogenesis and angiogenesis. 5 day RICE groups, in which RIC was started five days prior to exercise, demonstrated the greatest improvement among these parameters. The results also suggested that the HIF-1α/PLD2/mTOR signaling pathway may be implicated in post-stroke neuroplasticity. CONCLUSIONS: RICE, particularly RIC initiation at hour 6 post-reperfusion followed by exercise on day 5, enhanced post-stroke rehabilitation in rats.