Associations of Proinflammatory Cytokines With the Risk of Recurrent Stroke

Correlations of Levels of Peripheral Blood Inflammatory Cytokines and Serum Lipoprotein-Associated Phospholipase-A2 with Acute Ischemic Stroke and Their Early Prognostic Value

Respecting the significant role of inflammation in acute ischemic stroke (AIS) development, we explored the correlations of inflammatory cytokines and lipoprotein-associated phospholipase-A2 (Lp-PLA2) with AIS and their early prognostic value. The retrospectively enrolled subjects [Study (AIS patients) and Control (healthy volunteers) groups] were determined for serum index levels. Neurological impairment and early prognosis of AIS patients were assessed. The relationship of National Institutes of Health Stroke Scale (NIHSS) and the indexes and the risk factors and predictive value of peripheral blood inflammatory cytokines combined with Lp-PLA2 for poor early prognosis were analyzed. Interleukin (IL)-1β, IL-6, tumor necrosis factor-α (TNF-α), and Lp-PLA2 levels rose in AIS patients, while IL-10 dropped. The NIHSS score positively correlated with IL-1β, TNF-α, and Lp-PLA2 and negatively correlated with IL-10. As AIS aggravated, IL-1β, IL-6, TNF-α, and Lp-PLA2 rose dependently, but IL-10 dropped. Patients in the poor early prognosis group had higher diabetes proportions, NIHSS scores and serum IL-1β, IL-6, TNF-α, and Lp-PLA2 levels at admission, as well as lower IL-10 levels than those in the good early prognosis group. IL-6, IL-1β, TNF-α, and Lp-PLA2 were risk factors, but IL-10 was a protective factor against poor early prognosis in AIS patients, with their combined detection showing high predictive value. Collectively, highly expressed IL-6, TNF-α, IL-1β, and Lp-PLA2 and lowly expressed IL-10 in patients with AIS closely related to AIS development and early prognosis, and their combination could increase the predictive value of NIHSS for AIS poor early prognosis.

Molecular and Neuroimaging Profile Associated with the Recurrence of Different Types of Strokes: Contribution from Real-World Data

Objective: This study aimed to investigate potential specific molecular and neuroimaging biomarkers for stroke subtype recurrence to improve secondary stroke prevention. Methods: A retrospective analysis was conducted on a prospective stroke biobank. The main endpoint was to evaluate the association between different biomarkers and the recurrence of stroke subtypes. Serum levels of interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-a) were analyzed as inflammation biomarkers; N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and microalbuminuria were used as atrial/endothelial dysfunction biomarkers, while leukoaraiosis (LA) and soluble TNF-like inducers of apoptosis (sTWEAK) were used as biomarkers for blood-brain barrier dysfunction. Demographic and clinical variables were also included. Results: A total of 5038 stroke patients were included, with a mean follow-up of 4.9 years (±3.3). Stroke recurrences were observed in 18.4% of patients (927 individuals). The main results found were as follows: LA was independently associated with lacunar stroke recurrence (adjusted OR 9.50; 95% CI: 3.12-28.93). NT-pro-BNP levels higher than >1000 pg/mL were independently associated with cardioembolic stroke recurrence (adjusted OR 1.80; 95% CI: 1.23-2.61). Persistently elevated TNF-a levels (>24 pg/mL) after stroke recurrence showed an adjusted OR of 21.26 (95% CI: 12.42-37.59) for atherothrombotic subtype, whereas persistently high sTWEAK levels (>7000 pg/mL) after a second hemorrhagic stroke showed an adjusted OR of 4.81 (95% CI: 2.86-8.07) for hemorrhagic subtype. Conclusions: The presence of LA and high levels of NT-pro-BNP, TNF-a, and sTWEAK were associated with an increased risk for lacunar, cardioembolic, atherothrombotic, and hemorrhagic stroke recurrences, respectively.

Mendelian randomization assessing causal relationship between fibrinogen levels and ischemic stroke

OBJECTIVE

High fibrinogen levels are associated with an increased risk of ischaemic stroke (IS). We used mendelian randomisation (MR) to explore a potential causal relationship.

MATERIALS AND METHODS

Data for assessing the relationship between gene variant, disease and biological levels needed for a MR approach was collected using a meta-analytical approach. Inverse-variance weighted (IVW) approach was used for the main analyses and alternative approach for sensitivity analyses. The relationship between fibrinogen levels and IS was assessed using Odds Ratio (OR), while mean difference (g/L) was used for the relationship between SNP (rs1800790) and fibrinogen levels.

RESULTS

The variant FGB rs1800790 SNP was interrogated as an instrumental variable of fibrinogen levels. A meta-analysis with 24 studies (12 case-control and 12 cohort studies, totalling 20,902 cases and 76,510 controls was conducted. Homozygotes (AG) of rs1800790 have 0.14g/L (95%CI: 0.08-0.19, P<0.001) and minor allele (AA) have 0.18g/L (95%CI: 0.01-0.35, P=0.037) higher levels of plasma fibrinogen concentration compared with homozygous for the major allele (GG). The risk of IS was significantly increased in 1-g/L (OR=1.83, 95%CI: 0.92-3.62, P=0.084), or 1-SD of fibrinogen levels (OR=1.39, 95%CI: 1.03-1.87, P=0.030), or above median levels (OR=1.22, 95%CI: 1.02-1.46, P=0.029) or categorical levels tertiles (OR=1.50, 95%CI: 1.26-1.79, P<0.001). Each 1-g/L increase in fibrinogen levels was causally associated with a higher risk of ischemic stroke (OR=2.28, 95%CI: 1.53-3.03, P<0.001) in the Mendelian randomisation analysis.

CONCLUSIONS

Elevated fibrinogen levels are a causative risk factor for ischaemic stroke with each 1g/L increase doubling its risk.

A Review on Current Aspects of Curcumin-Based Effects in Relation to Neurodegenerative, Neuroinflammatory and Cerebrovascular Diseases

Curcumin is among the most well-studied natural substances, known for its biological actions within the central nervous system, its antioxidant and anti-inflammatory properties, and human health benefits. However, challenges persist in effectively utilising curcumin, addressing its metabolism and passage through the blood-brain barrier (BBB) in therapies targeting cerebrovascular diseases. Current challenges in curcumin's applications revolve around its effects within neoplastic tissues alongside the development of intelligent formulations to enhance its bioavailability. Formulations have been discovered including curcumin's complexes with brain-derived phospholipids and proteins, or its liposomal encapsulation. These novel strategies aim to improve curcumin's bioavailability and stability, and its capability to cross the BBB, thereby potentially enhancing its efficacy in treating cerebrovascular diseases. In summary, this review provides a comprehensive overview of molecular pathways involved in interactions of curcumin and its metabolites, and brain vascular homeostasis. This review explores cellular and molecular current aspects, of curcumin-based effects with an emphasis on curcumin's metabolism and its impact on pathological conditions, such as neurodegenerative diseases, schizophrenia, and cerebral angiopathy. It also highlights the limitations posed by curcumin's poor bioavailability and discusses ongoing efforts to surpass these impediments to harness the full therapeutic potential of curcumin in neurological disorders.

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.

Increased Piezo1 expression in myofibroblasts in patients with symptomatic carotid atherosclerotic plaques undergoing carotid endarterectomy: A pilot study

OBJECTIVES

We aimed to investigate Piezo1 expression in myofibroblasts in symptomatic and asymptomatic patients undergoing carotid endarterectomy and its relationship with atherosclerotic plaque formation.

METHODS

This cross-sectional study analyzed carotid plaques of 17 randomly selected patients who underwent carotid endarterectomy from May 2015 to August 2017. In total, 51 sections (the most stenotic lesion, and the sections 5-mm proximal and distal) stained with hematoxylin-eosin and elastica-Masson were examined. Immunohistochemistry was performed using antibodies to Piezo1. The Piezo1 score of a section was calculated semiquantitatively, averaged across 30 randomly selected myofibroblasts in the fibrous cap of the plaque.

RESULTS

Of 17 patients (mean age: 74.2 ± 7.1 years), 15 were men, 9 had diabetes mellitus, and 13 had hypertension. Symptomatic patients had higher mean Piezo1 score than asymptomatic patients (1.78 ± 0.23 vs 1.34 ± 0.17, p < .001). Univariate linear regression analyses suggested an association between plaque rupture, thin-cap fibroatheroma and microcalcifications and the Piezo1 score (p = .001, .008, and 0.003, respectively).

CONCLUSIONS

Increased Piezo1 expression of myofibroblasts may be associated with atherosclerotic carotid plaque instability. Further study is warranted to support this finding.

IL-6 and stroke recurrence in ischemic stroke

Objective: This study aimed to evaluate the predictive value of IL-6 for stroke recurrence in acute ischemic stroke.Methods: Patients who were admitted within 48 h of onset were included. At 3-month, stroke recurrence was assessed. IL-6 levels were measured in serum samples taken upon admission.Results: Out of the 305 patients, 47 (15.4%) experienced a stroke recurrence. The risk of stroke recurrence increased by 8% (OR: 1.08; 95% CI: 1.04-1.11; p < 0.001) for every 1 pg/ml increase in IL-6 serum level, both in unadjusted and adjusted analyses (6%; OR: 1.06; 95% CI: 1.02-1.10; p = 0.001).Conclusion: The study supports the usefulness of IL-6 as a predictive biomarker for stroke recurrence after acute ischemic stroke.

Plasma fibrinogen and risk of vascular recurrence after ischaemic stroke: An individual participant and summary-level data meta-analysis of 11 prospective studies

INTRODUCTION

Inflammation is an emerging target for secondary prevention after stroke and randomised trials of anti-inflammatory therapies are ongoing. Fibrinogen, a putative pro-inflammatory marker, is associated with first stroke, but its association with major adverse cardiovascular events (MACE) after stroke is unclear.

MATERIALS AND METHODS

We did a systematic review investigating the association between fibrinogen and post-stroke vascular recurrence. Authors were invited to provide individual-participant data (IPD) and where available we did within-study multivariable analyses with adjustment for cardiovascular risk factors and medications. Adjusted summary-level data was extracted from published reports from studies that did not provide IPD. We pooled risk ratios (RR) by random-effects meta-analysis by comparing supra-median with sub-median fibrinogen levels and performed pre-specified subgroup analysis according to timing of phlebotomy after the index event.

RESULTS

Eleven studies were included (14,002 patients, 42,800 follow-up years), of which seven provided IPD. Fibrinogen was associated with recurrent MACE on unadjusted (RR 1.35, 95% CI 1.17-1.57, supra-median vs sub-median) and adjusted models (RR 1.21, 95% CI 1.06-1.38). Fibrinogen was associated with recurrent stroke on univariate analysis (RR 1.19, 95% CI 1.03-1.39), but not after adjustment (RR 1.11, 95% CI 0.94-1.31). The association with recurrent MACE was consistently observed in patients with post-acute (⩾14 days) fibrinogen measures (RR 1.29, 95% CI 1.16-1.45), but not in those with early phlebotomy (<14 days) (RR 0.98, 95% CI 0.82-1.18) (Pinteraction = 0.01). Similar associations were observed for recurrent stroke.

DISCUSSION AND CONCLUSION

Fibrinogen was independently associated with recurrence after stroke, but the association was modified by timing of phlebotomy. Fibrinogen measurements might be useful to identify patients who are more likely to derive benefit from anti-inflammatory therapies after stroke.

The differences of fibrinogen levels in various types of hemorrhagic transformations

Introduction

Hemorrhagic transformation (HT) is a serious complication that can occur spontaneously after an acute ischemic stroke (AIS) or after a thrombolytic/mechanical thrombectomy. Our study aims to explore the potential correlations between fibrinogen levels and the occurrence of spontaneous HT (sHT) and HT after mechanical thrombectomy (tHT).

Methods

A total of 423 consecutive AIS patients diagnosed HT who did not undergone thrombolysis and 423 age- and sex-matched patients without HT (non-HT) were enrolled. Fibrinogen levels were measured within 24 h of admission after stroke. The cohorts were trisected according to fibrinogen levels. The HT were further categorized into hemorrhagic infarction (HI) or parenchymal hematoma (PH) based on their imaging characteristics.

Results

In sHT cohort, fibrinogen levels were higher in HT patients than non-HT patients (p < 0.001 versus p = 0.002). High fibrinogen levels were associated with the severity of HT. HT patients without atrial fibrillation (AF) had higher levels of fibrinogen compared to non-HT (median 3.805 vs. 3.160, p < 0.001). This relationship did not differ among AF patients. In tHT cohort, fibrinogen levels were lower in HT patients than non-HT patients (p = 0.002). Lower fibrinogen levels were associated with the severity of HT (p = 0.004). The highest trisection of fibrinogen both in two cohorts were associated with HT [sHT cohort: OR = 2.515 (1.339-4.725), p = 0.016; that cohort: OR = 0.238 (0.108-0.523), p = 0.003].

Conclusion

Our study suggests that lower fibrinogen level in sHT without AF and higher fibrinogen level in tHT are associated with more severe HT.

Targeting inflammation to reduce recurrent stroke

BACKGROUND

Approximately one in four stroke patients suffer from recurrent vascular events, underlying the necessity to improve secondary stroke prevention strategies. Immune mechanisms are causally associated with coronary atherosclerosis. However, stroke is a heterogeneous disease and the relative contribution of inflammation across stroke mechanisms is not well understood. The optimal design of future randomized control trials (RCTs) of anti-inflammatory therapies to prevent recurrence after stroke must be informed by a clear understanding of the prognostic role of inflammation according to stroke subtype and individual patient factors.

AIM

In this narrative review, we discuss (1) inflammatory pathways in the etiology of ischemic stroke subtypes; (2) the evidence on inflammatory markers and vascular recurrence after stroke; and (3) review RCT evidence of anti-inflammatory agents for vascular prevention.

SUMMARY OF REVIEW

Experimental work, genetic epidemiological data, and plaque-imaging studies all implicate inflammation in atherosclerotic stroke. However, emerging evidence also suggests that inflammatory mechanisms are also important in other stroke mechanisms. Advanced neuroimaging techniques support the role of neuroinflammation in blood-brain barrier dysfunction in cerebral small vessel disease (cSVD). Systemic inflammatory processes also promote atrial cardiopathy, incident and recurrent atrial fibrillation (AF). Although several inflammatory markers have been associated with recurrence after stroke, interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) are presently the most promising markers to identify patients at increased vascular risk. Several RCTs have shown that anti-inflammatory therapies reduce vascular risk, including stroke, in coronary artery disease (CAD). Some, but not all of these trials, selected patients on the basis of elevated hsCRP. Although unproven after stroke, targeting inflammation to reduce recurrence is a compelling strategy and several RCTs are ongoing.

CONCLUSION

Evidence points toward the importance of inflammation across multiple stroke etiologies and potential benefit of anti-inflammatory targets in secondary stroke prevention. Taking the heterogeneous stroke etiologies into account, the use of serum biomarkers could be useful to identify patients with residual inflammatory risk and perform biomarker-led patient selection for future RCTs.

Serum from Stroke Patients with High-Grade Carotid Stenosis Promotes Cyclooxygenase-Dependent Endothelial Dysfunction in Non-ischemic Mice Carotid Arteries

Atherosclerosis is responsible for 20% of ischemic strokes, and severe carotid stenosis is associated with a higher incidence of first-ever and recurrent strokes. The release of pro-inflammatory mediators into the blood in severe atherosclerosis may aggravate endothelial dysfunction after stroke contributing to impair disease outcomes. We hypothesize that environments of severe carotid atherosclerotic disease worsen endothelial dysfunction in stroke linked to enhanced risk of further cerebrovascular events. We mounted nonischemic common carotid arteries from 2- to 4-month-old male Oncins France 1 mice in tissue baths for isometric contraction force measurements and exposed them to serum from men with a recent ischemic stroke and different degrees of carotid stenosis: low- or moderate-grade stenosis (LMGS; < 70%) and high-grade stenosis (HGS; ≥ 70%). The results show that serum from stroke patients induced an impairment of acetylcholine relaxations in mice carotid arteries indicative of endothelium dysfunction. This effect was more pronounced after incubation with serum from patients with a recurrent stroke or vascular death within 1 year of follow-up. When patients were stratified according to the degree of stenosis, serum from HGS patients induced more pronounced carotid artery endothelial dysfunction, an effect that was associated with enhanced circulating levels of IL-1β. Mechanistically, endothelial dysfunction was prevented by both nonselective and selective COX blockade. Altogether, the present findings add knowledge on the understanding of the mechanisms involved in the increased risk of stroke in atherosclerosis and suggest that targeting COX in the carotid artery wall may represent a potential novel therapeutic strategy for secondary stroke prevention.

Initial stroke severity and discharge outcome in patients with muscle mass deficit

This study aimed to investigate the association between muscle mass deficit and the initial severity of ischemic stroke. The impact of muscle mass deficit on the discharge outcome was also evaluated. This retrospective study included 660 patients with acute ischemic stroke who underwent bioelectrical impedance analyses. We compared the National Institute of Health Stroke Scale (NIHSS) score, occurrence of moderate stroke (NIHSSS ≥ 5) at admission, and unfavorable functional outcome (modified Rankin Scale score ≥ 2) at discharge between patients with and without muscle mass deficit using Poisson and logistic regression analyses. The mean age of the study patients was 65.6 ± 13.0, and 63.3% were males. Muscle mass deficit was present in 24.4% of patients. Muscle mass deficit was significantly and independently associated with NIHSS score or moderate stroke (all p < 0.05). This association was noted regardless of patient characteristics. Among the respective NIHSS items, muscle mass deficit was significantly associated with facial palsy, motor function of the arm or leg, limb ataxia, and dysarthria. Muscle mass deficit also led to unfavorable functional outcome, which was mediated by the initial NIHSS score. In conclusion, muscle mass deficit is associated with higher NIHSS score and unfavorable functional outcome in patients with acute ischemic stroke.

Secondary Prevention and Extreme Cardiovascular Risk Evaluation (SEVERE-1), Focus on Prevalence and Associated Risk Factors: The Study Protocol

INTRODUCTION

Despite significant improvement in secondary CardioVascular (CV) preventive strategies, some acute and chronic coronary syndrome (ACS and CCS) patients will suffer recurrent events (also called "extreme CV risk"). Recently new biochemical markers, such as uric acid (UA), lipoprotein A [Lp(a)] and several markers of inflammation, have been described to be associated with CV events recurrence. The SEcondary preVention and Extreme cardiovascular Risk Evaluation (SEVERE-1) study will accurately characterize extreme CV risk patients enrolled in cardiac rehabilitation (CR) programs.

AIM

 Our aims will be to describe the prevalence of extreme CV risk and its association with newly described biochemical CV risk factors.

AIM

Our aims will be to describe the prevalence of extreme CV risk and its association with newly described biochemical CV risk factors.

METHODS

We will prospectively enrol 730 ACS/CCS patients at the beginning of a CR program. Extreme CV risk will be retrospectively defined as the presence of a previous (within 2 years) CV events in the patients' clinical history. UA, Lp(a) and inflammatory markers (interleukin-6 and -18, tumor necrosis factor alpha, C-reactive protein, calprotectin and osteoprotegerin) will be assessed in ACS/CCS patients with extreme CV risk and compared with those without extreme CV risk but also with two control groups: 1180 hypertensives and 765 healthy subjects. The association between these biomarkers and extreme CV risk will be assessed with a multivariable model and two scoring systems will be created for an accurate identification of extreme CV risk patients. The first one will use only clinical variables while the second one will introduce the biochemical markers. Finally, by exome sequencing we will both evaluate polygenic risk score ability to predict recurrent events and perform mendellian randomization analysis on CV biomarkers.

CONCLUSIONS

Our study proposal was granted by the European Union PNRR M6/C2 call. With this study we will give definitive data on extreme CV risk prevalence rising attention on this condition and leading cardiologist to do a better diagnosis and to carry out a more intensive treatment optimization that will finally leads to a reduction of future ACS recurrence. This will be even more important for cardiologists working in CR that is a very important place for CV risk definition and therapies refinement.

Immunoinflammatory Background of Neuronal Damage in Stroke

Ischemic stroke is caused by a reduction in blood flow to the brain and is a major cause of mortality and disability worldwide [...].

Inflammatory biomarkers of ischemic stroke

Ischemic stroke remains the second leading cause of death and among the major causes of morbidity worldwide. Therapeutic options are currently limited to early reperfusion strategies, while pharmacological neuroprotective strategies despite showing promising results in the experimental setting constantly failed to enter the clinical arena. Inflammation plays an important role in the pathophysiology of ischemic stroke and mediators of inflammation have been longtime investigated as possible prognostic marker and therapeutic target for stroke patients. Here, we summarized available evidence on the role of cytokines, soluble adhesion molecules and adipokines in the pathophysiology, prognosis and therapy of ischemic stroke.

Research progress on the protective mechanism of a novel soluble epoxide hydrolase inhibitor TPPU on ischemic stroke

Arachidonic Acid (AA) is the precursor of cerebrovascular active substances in the human body, and its metabolites are closely associated with the pathogenesis of cerebrovascular diseases. In recent years, the cytochrome P450 (CYP) metabolic pathway of AA has become a research hotspot. Furthermore, the CYP metabolic pathway of AA is regulated by soluble epoxide hydrolase (sEH). 1-trifluoromethoxyphenyl-3(1-propionylpiperidin-4-yl) urea (TPPU) is a novel sEH inhibitor that exerts cerebrovascular protective activity. This article reviews the mechanism of TPPU's protective effect on ischemic stroke disease.

Role of plaque inflammation in symptomatic carotid stenosis

Objective

Prior studies have shown that plaque inflammation on FDG-PET and the symptomatic carotid atheroma inflammation lumen-stenosis (SCAIL) score were associated with recurrent ischemic events, but the findings have thus far not been widely validated. Therefore, we aimed to validate the findings of prior studies.

Methods

A single-center prospective cohort study that recruited patients with (1) recent TIA or ischemic stroke within the past 30 days, (2) ipsilateral carotid artery stenosis of ≥50%, and (3) were not considered for early carotid revascularization. The (1) maximum standardized uptake value (SUVmax) of the symptomatic carotid plaque, (2) the SCAIL score, and (3) stenosis severity of the symptomatic carotid artery were measured for all patients. The outcomes were (1) a 90-day ipsilateral ischemic stroke and (2) a 90-day ipsilateral symptomatic TIA or major adverse cardiovascular event (MACE).

Results

Among the 131 patients included in the study, the commonest cardiovascular risk factor was hypertension (95 patients, 72.5%), followed by diabetes mellitus (77 patients, 58.8%) and being a current smoker (64 patients, 48.9%). The median (IQR) duration between the index cerebral ischemic event and recruitment to the study was 1 (0, 2.5) days. The median (IQR) duration between the index cerebral ischemic event and FDG-PET was 5 (4, 7) days. A total of 14 (10.7%) patients had a 90-day stroke, and 41 (31.3%) patients had a 90-day TIA or MACE. On comparison of the predictive performances of the SCAIL score and SUVmax, SUVmax was found to be superior to the SCAIL score for predicting both 90-day ipsilateral ischemic stroke (AUC: SCAIL = 0.79, SUVmax = 0.92; p < 0.001; 95% CI = 0.072, 0.229) and 90-day TIA or MACE (AUC: SCAIL = 0.76, SUVmax = 0.84; p = 0.009; 95% CI = 0.020, 0.143).

Conclusion

Plaque inflammation as quantified on FDG-PET may serve as a reliable biomarker for risk stratification among patients with ECAD and recent TIA or ischemic stroke. Future studies should evaluate whether patients with significant plaque inflammation as quantified on FDG-PET benefit from carotid revascularization and/or anti-inflammatory therapy.

Role of Endogenous Lipopolysaccharides in Neurological Disorders

Lipopolysaccharide (LPS) is a cell-wall immunostimulatory endotoxin component of Gram-negative bacteria. A growing body of evidence reveals that alterations in the bacterial composition of the intestinal microbiota (gut dysbiosis) disrupt host immune homeostasis and the intestinal barrier function. Microbial dysbiosis leads to a proinflammatory milieu and systemic endotoxemia, which contribute to the development of neurodegenerative diseases and metabolic disorders. Two important pathophysiological hallmarks of neurodegenerative diseases (NDDs) are oxidative/nitrative stress and inflammation, which can be initiated by elevated intestinal permeability, with increased abundance of pathobionts. These changes lead to excessive release of LPS and other bacterial products into blood, which in turn induce chronic systemic inflammation, which damages the blood-brain barrier (BBB). An impaired BBB allows the translocation of potentially harmful bacterial products, including LPS, and activated neutrophils/leucocytes into the brain, which results in neuroinflammation and apoptosis. Chronic neuroinflammation causes neuronal damage and synaptic loss, leading to memory impairment. LPS-induced inflammation causes inappropriate activation of microglia, astrocytes, and dendritic cells. Consequently, these alterations negatively affect mitochondrial function and lead to increases in oxidative/nitrative stress and neuronal senescence. These cellular changes in the brain give rise to specific clinical symptoms, such as impairment of locomotor function, muscle weakness, paralysis, learning deficits, and dementia. This review summarizes the contributing role of LPS in the development of neuroinflammation and neuronal cell death in various neurodegenerative diseases.

Selected Mediators of Inflammation in Patients with Acute Ischemic Stroke

During a stroke, a series of biochemical and metabolic changes occur which eventually lead to the death of cells by necrosis or apoptosis. This is a multi-stage process involving oxidative stress and an inflammatory response from the first signs of occlusion of a blood vessel until the late stages of regeneration and healing of ischemic tissues. The purpose of the research was to assess the concentration of pro-inflammatory cytokines IL-6 and TNF-α in the blood serum of patients with ischemic stroke (AIS) and to investigate their role as new markers in predicting functional prognosis after thrombolytic therapy. The researches have shown that the concentrations of the measured biomarkers were higher compared to the control group. Serum levels of IL-6 and THF-α before the initiation of intravenous thrombolysis were lower in the subgroup of patients with a favourable functional result (mRS: 0−2 pts) compared to the group of patients with an unfavourable functional result (mRS: 3−6 pts). A positive correlation was found between the concentration of IL-6 and TNF-α in patients with AIS during <4.5 h and on one day after the onset of stroke, which means that the concentration of IL-6 increases with the increase in TNF-α concentration. It has also been shown that higher levels of IL-6 in the acute phase of stroke and on the first and seventh days, and TNF-α during onset, were associated with poorer early and late prognosis in patients treated with intravenous thrombolysis. A relationship was found between the level of IL-6 and TNF-α in the subacute AIS and the severity of the neurological deficit. It has been shown that the investigated biomarkers may be a prognostic factor in the treatment of thrombolytic AIS.

Role of Glial Cell-Derived Oxidative Stress in Blood-Brain Barrier Damage after Acute Ischemic Stroke

The integrity of the blood-brain barrier (BBB) is mainly maintained by endothelial cells and basement membrane and could be regulated by pericytes, neurons, and glial cells including astrocytes, microglia, oligodendrocytes (OLs), and oligodendrocyte progenitor cells (OPCs). BBB damage is the main pathological basis of hemorrhage transformation (HT) and vasogenic edema after stroke. In addition, BBB damage-induced HT and vasogenic edema will aggravate the secondary brain tissue damage. Of note, after reperfusion, oxidative stress-initiated cascade plays a critical role in the BBB damage after acute ischemic stroke (AIS). Although endothelial cells are the target of oxidative stress, the role of glial cell-derived oxidative stress in BBB damage after AIS also should receive more attention. In the current review, we first introduce the physiology and pathophysiology of the BBB, then we summarize the possible mechanisms related to BBB damage after AIS. We aim to characterize the role of glial cell-derived oxidative stress in BBB damage after AIS and discuss the role of oxidative stress in astrocytes, microglia cells and oligodendrocytes in after AIS, respectively.

Right Atrial Fluorodeoxyglucose Uptake Is a Risk Factor for Stroke and Improves Prediction of Stroke Above the CHA2DS2-VASc Score in Patients With Atrial Fibrillation

Background

Atrial fibrillation (AF) is a common arrhythmia, and its most severe and dreaded complication is stroke. The CHA2DS2-VASc score is currently recommended for stroke risk assessment in AF. We aimed to explore the relationship between atrial FDG uptake and stroke and whether atrial FDG uptake could provide incremental value above the CHA2DS2-VAS score to predict stroke in AF by 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT).

Materials and Methods

From September 2017 to December 2020, we retrospectively enrolled 230 patients (115 with AF and 115 without AF as the non-AF group, matched for the date of PET/CT examination and the basic characteristics of the patient) who underwent 18F-FDG PET/CT due to tumor screening or preoperative staging after prolonged fasting and followed up for at least 12 months from the date of PET/CT examination; the endpoint event is the occurrence of stroke. We visually and quantitatively analyzed 18F-FDG uptake in the right and left atria (RA/LA), right and left atrial appendage (RAA/LAA), right and left ventricle (RV/LV), and collected clinical features. In addition, according to the endpoint event (stroke), the enrolled population was divided into the stroke group and non-stroke group, and relevant clinical features and atrial FDG uptake indicators of the two groups were analyzed. Univariate and multivariate Cox regression analyzes were used to analyze the risk factors of stroke events. The Kaplan–Meier survival curve of atrial FDG uptake was drawn, and the log-rank method was used to compare the differences in the survival curves of the two groups. Receiver operating characteristic (ROC) curves were used to examine the discriminatory power of atrial FDG uptake in predicting stroke and determine whether the addition of atrial FDG uptake improves predictive value beyond the CHA2DS2-VASc score for stroke.

Results

In the AF group, more than half of patients had RA FDG uptake and one-fifth had LA FDG uptake, while one patient had RA FDG uptake and two patients had LA FDG uptake in the non-AF group. In quantitative analysis, the maximum standardized uptake value (SUVmax) of the RA and LA in the AF group was significantly higher than that of the non-AF group (all P &lt; 0.001). We followed up the patients for 28 ± 10 months, and finally, 31 patients had stroke. In the stroke group, atrial fibrillation, RA SUVmax, RAA SUVmax, LAA SUVmax, age ≥ 75 years, and left atrial dilation were significantly higher than those of the non-stroke group (all P &lt; 0.05). Multivariate Cox regression analysis showed that high RA SUVmax (RA SUVmax ≥ 2.62) was an independent risk factor for stroke (HR = 4.264, 95% CI 1.368–13.293, P = 0.012). By using the log-rank test, patients with high RA SUVmax had a significantly higher incidence of stroke compared with patients with low RA SUVmax (P &lt; 0.001). Addition of high RA SUVmax to the CHA2DS2-VASc score could predict stroke more effectively, with a larger AUC 0.790 (P &lt; 0.001).

Conclusion

This study found a significant correlation between atrial FDG uptake and AF, especially in RA. Meanwhile, RA FDG uptake is an independent risk factor for stroke, and patients with high RA SUVmax have a significantly higher risk of stroke. Moreover, RA FDG uptake improves prediction of stroke above the CHA2DS2-VASc score in patients with AF.

A Nomogram for Predicting Patent Foramen Ovale-Related Stroke Recurrence

Background

The high prevalence of patent foramen ovale (PFO) in cryptogenic stroke suggested a stroke-causing role for PFO. As risk factors for recurrence of such stroke are not recognized, clinicians cannot sufficiently identify, treat, and follow-up high-risk patients. Therefore, this study aimed to establish a prediction model for PFO-related stroke recurrence.

Methods

This study included 392 patients with PFO-related stroke in a training set and 164 patients with PFO-related stroke in an independent validation set. In the training set, independent risk factors for recurrence identified using forward stepwise Cox regression were included in nomogram 1, and those identified using least absolute shrinkage and selection operator(LASSO)regression were included in nomogram 2. Nomogram performance and discrimination were assessed using the concordance index (C-index), area under the curve (AUC), calibration curve, and decision curve analyses (DCA). The results were also validated in the validation set.

Results

Nomogram 1 was based on homocysteine (Hcy), high-sensitivity C-reactive protein (hsCRP), and albumin (ALB), and nomogram 2 was based on age, diabetes, hypertension, right-to-left shunt, ALB, prealbumin, hsCRP, and Hcy. The C-index of nomogram 1 was 0.861, which was not significantly different from that of nomogram 2 (0.893). The 2- and 5-year AUCs of nomogram 1 were 0.863 and 0.777, respectively. In the validation set, nomogram 1 still had good discrimination (C-index, 0.862; 2-year AUC, 0.839; 5-year AUC, 0.990). The calibration curve showed good homogeneity between the prediction by nomogram 1 and the actual observation. DCA demonstrated that nomogram 1 was clinically useful. Moreover, patients were successfully divided into two distinct risk groups (low and high risk) for recurrence rate by nomogram 1.

Conclusions

Nomogram 1, based on Hcy, hsCRP, and ALB levels, provided a more clinically realistic prognostic prediction for patients with PFO-related stroke. This model could help patients with PFO-related stroke to facilitate personalized prognostic evaluations.

Biochemical clusters predict mortality and reported inability to work 10 ​years later

BACKGROUND

Chronic systemic inflammation has been linked to premature mortality and limited somatic as well as mental health with consequences for capability to work and everyday functioning. We recently identified three biochemical clusters of endocrine and immune parameters (C-reactive protein (CRP), interleukin-6 (IL-6), fibrinogen, cortisol and creatinine) in participants, age 35-81 years, of the open access Midlife in the United States Study (MIDUS) dataset. These clusters have been validated in an independent cohort of Japanese mid-life adults. Among these clusters, the one characterized by high inflammation coupled with low cortisol and creatinine concentrations was associated with the highest disease burden, referred to as high-risk cluster in the following. The current study aims to further examine the nature of this cluster and specifically whether it predicts mortality and the reported inability to work the last 30 days 10 years after the biomarker assessment.

METHODS AND FINDINGS

Longitudinally assessed health data from N ​= ​1234 individuals were analyzed in the current study. Logistic regression analyses were performed to predict mortality within one decade after first assessment (T0 ​= ​first assessment; T1 ​= ​second assessment). General linear models were used to predict the number of days study participants were unable to work due to health issues in the last 30 days (assessed at T1, analyses restricted to individuals <70 years of age). Biological sex, disease burden, and age at T0 were used as covariates in all analyses. Individuals in the previously identified high-risk cluster had a higher risk for mortality (22% of individuals deceased between T0 and T1 versus 10% respectively 9% in the two other clusters). Logistic regression models predicting mortality resulted in a significant difference between individuals from the high-risk cluster compared to those from an identified reference cluster (indicator method, p ​= ​.012), independently of age and disease burden. Furthermore, individuals in the high-risk cluster reported a higher number of disability days during the past 30 days (3.4 days in the high-risk cluster versus 1.5 respectively 1.0 days in the reference clusters) assessed at T1. All pairwise comparisons involving the high-risk cluster were significant (all ps ​< ​.001).

CONCLUSIONS

Immune-endocrine profiles are predictive of mortality within the following decade over and above age and disease burden. The findings thus highlight the importance of biomarker-based risk profiling that may provide new targets for interventions in the context of preventive medicine in the transition from health to disease and disease-related mortality.

How biomarker patterns can be utilized to identify individuals with a high disease burden: a bioinformatics approach towards predictive, preventive, and personalized (3P) medicine

Prevalences of non-communicable diseases such as depression and a range of somatic diseases are continuously increasing requiring simple and inexpensive ways to identify high-risk individuals to target with predictive and preventive approaches. Using k-mean cluster analytics, in study 1, we identified biochemical clusters (based on C-reactive protein, interleukin-6, fibrinogen, cortisol, and creatinine) and examined their link to diseases. Analyses were conducted in a US American sample (from the Midlife in the US study, N = 1234) and validated in a Japanese sample (from the Midlife in Japan study, N = 378). In study 2, we investigated the link of the biochemical clusters from study 1 to childhood maltreatment (CM). The three identified biochemical clusters included one cluster (with high inflammatory signaling and low cortisol and creatinine concentrations) indicating the highest disease burden. This high-risk cluster also reported the highest CM exposure. The current study demonstrates how biomarkers can be utilized to identify individuals with a high disease burden and thus, may help to target these high-risk individuals with tailored prevention/intervention, towards personalized medicine. Furthermore, our findings raise the question whether the found biochemical clusters have predictive character, as a tool to identify high-risk individuals enabling targeted prevention. The finding that CM was mostly prevalent in the high-risk cluster provides first hints that the clusters could indeed have predictive character and highlight CM as a central disease susceptibility factor and possibly as a leverage point for disease prevention/intervention.

A Score of Low-Grade Inflammation for Predicting Stroke Recurrence in Patients with Ischemic Stroke

Background and Purpose

The impact of low-grade inflammation (LGI) on stroke recurrence has not been well studied yet. We aimed to evaluate the association between LGI and stroke recurrence in patients with ischemic stroke.

Methods

Patients with first-ever ischemic stroke diagnosed within 72 hours of symptoms onset were consecutively recruited from the Nanjing Stroke Registry Program. C-reactive protein (CRP) level, white blood cell (WBC) count, platelet (PLT) count, and neutrophil-to-lymphocyte ratio (NLR) were conceived as low-grade inflammation biomarkers and combined into a standardized LGI score. The association of LGI score with the risk of stroke recurrence was analyzed with multivariate Cox regression models. Analyses accounting for the competing risk of stroke recurrence and death were also performed.

Results

Of the 1214 patients studied (median age, 61 years; male, 71.6%), 177 (14.6%) patients experienced a recurrent stroke with a median follow-up of 23.0 (interquartile ranges, 14.5-34.0) months. Patients with stroke recurrence had a higher LGI score (median, 3 versus -2; P < 0.001) than those without recurrence. The univariate analysis indicated that patients with LGI scores in the fourth quartile were more likely to have a stroke recurrence (hazard ratios [HR], 4.312; 95% confidence interval [CI], 2.675-6.952; P < 0.001). After adjusting for potential confounders, the association remained significant in the multivariate Cox regression model (HR, 4.080; 95% CI, 2.420-6.879; P < 0.001). Competing risks model and sensitivity analysis further confirmed this conclusion.

Conclusion

This study showed that an elevated LGI score was associated with a higher risk of stroke recurrence, independent of other vascular risk factors.

Elevated Serum Inflammatory Markers in Subacute Stroke Are Associated With Clinical Outcome but Not Modified by Aerobic Fitness Training: Results of the Randomized Controlled PHYS-STROKE Trial

Background: Inflammatory markers, such as C-reactive Protein (CRP), Interleukin-6 (IL-6), tumor necrosis factor (TNF)-alpha and fibrinogen, are upregulated following acute stroke. Studies have shown associations of these biomarkers with increased mortality, recurrent vascular risk, and poor functional outcome. It is suggested that physical fitness training may play a role in decreasing long-term inflammatory activity and supports tissue recovery.

Aim: We investigated the dynamics of selected inflammatory markers in the subacute phase following stroke and determined if fluctuations are associated with functional recovery up to 6 months. Further, we examined whether exposure to aerobic physical fitness training in the subacute phase influenced serum inflammatory markers over time.

Methods: This is an exploratory analysis of patients enrolled in the multicenter randomized-controlled PHYS-STROKE trial. Patients within 45 days of stroke onset were randomized to receive either four weeks of aerobic physical fitness training or relaxation sessions. Generalized estimating equation models were used to investigate the dynamics of inflammatory markers and the associations of exposure to fitness training with serum inflammatory markers over time. Multiple logistic regression models were used to explore associations between inflammatory marker levels at baseline and three months after stroke and outcome at 3- or 6-months.

Results: Irrespective of the intervention group, high sensitive CRP (hs-CRP), IL-6, and fibrinogen (but not TNF-alpha) were significantly lower at follow-up visits when compared to baseline (p all ≤ 0.01). In our cohort, exposure to aerobic physical fitness training did not influence levels of inflammatory markers over time. In multivariate logistic regression analyses, increased baseline IL-6 and fibrinogen levels were inversely associated with worse outcome at 3 and 6 months. Increased levels of hs-CRP at 3 months after stroke were associated with impaired outcome at 6 months. We found no independent associations of TNF-alpha levels with investigated outcome parameters.

Conclusion: Serum markers of inflammation were elevated after stroke and decreased within 6 months. In our cohort, exposure to aerobic physical fitness training did not modify the dynamics of inflammatory markers over time. Elevated IL-6 and fibrinogen levels in early subacute stroke were associated with worse outcome up to 6-months after stroke.

Clinical Trial Registration:ClinicalTrials.gov, NCT01953549.

Dose-Dependent Association of Inflammatory Cytokines with Carotid Atherosclerosis in Transient Ischaemic Attack: Implications for Clinical Trials

INTRODUCTION

The 5-year recurrence risk after ischaemic stroke and transient ischaemic attack (TIA) is 25-30%. Although inflammation may be a target for prevention trials, the contribution of plaque inflammation to acute cerebrovascular events remains unclear. We investigated the association of acute inflammatory cytokines and high-sensitivity C-reactive protein (CRP) with recently symptomatic carotid atherosclerosis in a prospective cohort study.

METHODS

Blood and Imaging markers of TIA BIO-TIA) is a multicentre prospective study of imaging and inflammatory markers in patients with TIA. Exclusion criteria were infection and other co-morbid illnesses associated with inflammation. CRP and serum cytokines (interleukin [IL]-6, IL-1β, IL-8, IL-10, IL-12, interferon-γ [IFN-γ] and tumour necrosis factor-α [TNF-α]) were measured. All patients had carotid imaging.

RESULTS

Two hundred and thirty-eight TIA cases and 64 controls (TIA mimics) were included. Forty-nine (20.6%) cases had symptomatic internal carotid artery stenosis. Pro-inflammatory cytokine levels increased in a dose-dependent manner across controls, TIA without carotid stenosis (CS), and TIA with CS (IL-1β, ptrend = 0.03; IL-6, ptrend < 0.0001; IL-8, ptrend = 0.01; interferon (IFN)-γ, ptrend = 0.005; TNF-α, ptrend = 0.003). Results were unchanged when DWI-positive cases were excluded. On multivariable linear regression, only age (p = 0.01) and CS (p = 0.04) independently predicted log-IL-6. On multivariable Cox regression, CRP was the only independent predictor of 90-day stroke recurrence (adjusted hazard ratio per 1-unit increase 1.03 [95% CI: 1.01-1.05], p = 0.003).

CONCLUSION

Symptomatic carotid atherosclerosis was associated with elevated cytokines in TIA patients after controlling for other sources of inflammation. High-sensitivity CRP was associated with recurrent ischaemic stroke at 90 days. These findings implicate acute plaque inflammation in the pathogenesis of cerebral thromboembolism and support a rationale for randomized trials of anti-inflammatory therapy for stroke patients, who were excluded from coronary trials.

Inflammatory cytokines, high-sensitivity C-reactive protein, and risk of one-year vascular events, death, and poor functional outcome after stroke and transient ischemic attack

Background

Inflammation driven by pro-inflammatory cytokines is a new therapeutic target in coronary disease. Few data exist on the association of key upstream cytokines and post-stroke recurrence. In a prospective cohort study, we investigated the association between pivotal cytokines, high-sensitivity C-reactive protein (hsCRP) and one-year outcomes.

Methods

BIO-STROKETIA is a multi-center prospective cohort study of non-severe ischemic stroke (modified Rankin score ≤ 3) and transient ischemic attack. Controls were patients with transient symptoms attending transient ischemic attack clinics with non-ischemic final diagnosis. Exclusion criteria were severe stroke, infection, and other pro-inflammatory disease; hsCRP and cytokines (interleukin (IL) 6, IL-1β, IL-8, IL-10, IL-12, interferon-γ (IFN-γ), tumor-necrosis factor-α (TNF-α)) were measured. The primary outcome was one-year recurrent stroke/coronary events (fatal and non-fatal).

Results

In this study, 680 patients (439 stroke, 241 transient ischemic attack) and 68 controls were included. IL-6, IL-1β, IL-8, IFN-γ, TNF-α, and hsCRP were higher in stroke/transient ischemic attack cases (p ≤ 0.01 for all). On multivariable Cox regression, IL-6, IL-8, and hsCRP independently predicted one-year recurrent vascular events (adjusted hazard ratios (aHR) per-quartile increase IL-6 1.31, confidence interval (CI) 1.02–1.68, p = 0.03; IL-8 1.47, CI 1.15–1.89, p = 0.002; hsCRP 1.28, CI 1.01–1.62, p = 0.04). IL-6 (aHR 1.98, CI 1.26–3.14, p = 0.003) and hsCRP (aHR 1.81, CI 1.20–2.74, p = 0.005) independently predicted one-year fatality. IL-6 and hsCRP (adjusted odds ratio per-unit increase 1.02, CI 1.01–1.04) predicted poor functional outcome, with a trend for IL-1β (p = 0.054).

Conclusion

Baseline inflammatory cytokines independently predicted late recurrence, supporting a rationale for randomized trials of anti-inflammatory agents for prevention after stroke and suggesting that targeted therapy to high-risk patients with high baseline inflammation may be beneficial.

Post-traumatic stress disorder and its association with stroke and stroke risk factors: A literature review

Stroke is a major cause of mortality and disability globally that has multiple risk factors. A risk factor that has recently gained more attention is post-traumatic stress disorder (PTSD). Literature searches were carried out for updated PTSD information and for the relationship between PTSD and stroke. The review was divided into two sections, one exploring PTSD as an independent risk factor for stroke, with a second concentrating on PTSD's influence on stroke risk factors. The study presents accumulating evidence that shows traumatic stress predicts stroke and is also linked to many major stroke risk factors. The review contributes knowledge to stroke aetiology and acts as a reference for understanding the relationship between PTSD and stroke. The information presented indicates that screening and identification of traumatic experience would be beneficial for directing stroke patients to appropriate psychological and lifestyle interventions. In doing so, the burden of stroke may be reduced worldwide.

Interleukin-6, C-reactive protein, fibrinogen, and risk of recurrence after ischaemic stroke: Systematic review and meta-analysis

BACKGROUND

Recent randomised trials showed benefit for anti-inflammatory therapies in coronary disease but excluded stroke. The prognostic value of blood inflammatory markers after stroke is uncertain and guidelines do not recommend their routine measurement for risk stratification.

METHODS

We performed a systematic review and meta-analysis of studies investigating the association of C-reactive protein (CRP), interleukin-6 (IL-6) and fibrinogen and risk of recurrent stroke or major vascular events (MVEs). We searched EMBASE and Ovid Medline until 10/1/19. Random-effects meta-analysis was performed for studies reporting comparable effect measures.

RESULTS

Of 2,515 reports identified, 39 met eligibility criteria (IL-6, n = 10; CRP, n = 33; fibrinogen, n = 16). An association with recurrent stroke was reported in 12/26 studies (CRP), 2/11 (fibrinogen) and 3/6 (IL-6). On random-effects meta-analysis of comparable studies, CRP was associated with an increased risk of recurrent stroke [pooled hazard ratio (HR) per 1 standard-deviation (SD) increase in loge-CRP (1.14, 95% CI 1.06-1.22, p < 0.01)] and MVEs (pooled HR 1.21, CI 1.10-1.34, p < 0.01). Fibrinogen was also associated with recurrent stroke (HR 1.26, CI 1.07-1.47, p < 0.01) and MVEs (HR 1.31, 95% CI 1.15-1.49, p < 0.01). Trends were identified for IL-6 for recurrent stroke (HR per 1-SD increase 1.17, CI 0.97-1.41, p = 0.10) and MVEs (HR 1.22, CI 0.96-1.55, p = 0.10).

CONCLUSION

Despite evidence suggesting an association between inflammatory markers and post-stroke vascular recurrence, substantial methodological heterogeneity was apparent between studies. Individual-patient pooled analysis and standardisation of methods are needed to determine the prognostic role of blood inflammatory markers and to improve patient selection for randomised trials of inflammatory therapies.

Effects of ML351 and tissue plasminogen activator combination therapy in a rat model of focal embolic stroke

Thrombolytic stroke therapy with tissue plasminogen activator (tPA) is limited by risks of hemorrhagic transformation (HT). We have reported that a new 12/15-lipoxygenase (12/15-LOX) inhibitor ML351 reduced tPA related HT in mice subjected to experimental stroke under anticoagulation. In this study, we asked whether ML351 can ameliorate tPA induced HT in an embolic stroke model. Rats were subjected to embolic middle cerebral artery occlusion with 2 or 3 hr ischemia and tPA infusion, with or without ML351. Regional cerebral blood flow was monitored 2 hr after ischemia and continuously monitored for 1 hr after treatment for determining reperfusion. Hemoglobin was determined in brain homogenates and infarct volume was quantified at 24 hr after stroke.12/15-LOX, cluster of differentiation 68(CD68), immunoglobulin G (IgG), and tight junction proteins expression was detected by immunohistochemistry. ML351 significantly reduced tPA related hemorrhage after stroke without affecting its thrombolytic efficacy. ML351 also reduced blood-brain barrier disruption and improved preservation of junction proteins. ML351 and tPA combination improved neurological deficit of rats even though ML351 did not further reduce the infarct volume compared to tPA alone treated animals. Pro-inflammatory cytokines were suppressed by ML351 both in vivo and in vitro experiments. We further showed that ML351 suppressed the expression of c-Jun-N-terminal kinase (JNK) in brains and microglia cultures, whereas exogenous 12-HETE attenuated this effect in vitro. In conclusion, ML351 and tPA combination therapy is beneficial in ameliorating HT after ischemic stroke. This protective effect is probably because of 12/15-LOX inhibition and suppression of JNK-mediated microglia/macrophage activation.

The Role of C-Reactive Protein and Fibrinogen in the Development of Intracerebral Hemorrhage: A Mendelian Randomization Study in European Population

Background: The causal association of C-reactive protein (CRP) and fibrinogen on intracerebral hemorrhage (ICH) remains uncertain. We investigated the causal associations of CRP and fibrinogen with ICH using two-sample Mendelian randomization. Method: We used single-nucleotide polymorphisms associated with CRP and fibrinogen as instrumental variables. The summary data on ICH were obtained from the International Stroke Genetics Consortium (1,545 cases and 1,481 controls). Two-sample Mendelian randomization estimates were performed to assess with inverse-variance weighted and sensitive analyses methods including the weighted median, the penalized weighted median, pleiotropy residual sum and outlier (MR-PRESSO) approaches. MR-Egger regression was used to explore the pleiotropy. Results: The MR analyses indicated that genetically predicted CRP concentration was not associated with ICH, with an odds ratio (OR) of 1.263 (95% CI = 0.935-1.704, p = 0.127). Besides, genetically predicted fibrinogen concentration was not associated with an increased risk of ICH, with an OR of 0.879 (95% CI = 0.060-18.281; p = 0.933). No evidence of pleiotropic bias was detected by MR-Egger. The findings were overall robust in sensitivity analyses. Conclusions: Our findings did not support that CRP and fibrinogen are causally associated with the risk of ICH.

Inflammatory Markers in Severity of Intracerebral Hemorrhage II: A Follow Up Study

Introduction

Spontaneous intracerebral hemorrhage (ICH) results in significant morbidity and mortality. The pathogenesis of brain injury after ICH is thought to be due to mechanical damage followed by ischemic, cytotoxic, and inflammatory changes in the underlying and surrounding tissue. Various inflammatory and non-inflammatory biomarkers have been studied as predictors and potential therapeutic targets for intracerebral hemorrhage. Our prior study showed an association with low vascular endothelial growth factor (VEGF) levels and increased mortality. This current study looks to expand on our prior results and will look at the relationship between tumor necrosis factor alpha (TNFα), C-reactive protein (CRP), VEGF, Homocysteine (Hcy), and CRP to albumin ratio (CAR) in predicting outcomes and severity in spontaneous intracerebral hemorrhage.

Methods

We conducted a retrospective chart review of patients with spontaneous intracerebral hemorrhage with TNFα, CRP, VEGF, Hcy levels drawn on admission. Albumin and CRP levels on admission were used to calculate CAR. Ninety-nine patients were included in the study. Primary outcomes included death, early neurologic decline (END), and hemorrhage size. Secondary outcomes included late neurologic decline (LND), Glasgow Coma Scale (GCS) on admission, GCS on discharge, ICH score, change in hemorrhage size, need for surgical intervention, and length of ICU stay.

Results

A total of 99 patients were included in this study, with 42% requiring surgical intervention and an overall mortality of 16%. Basal ganglia hemorrhage was seen in 41% of patients. Hcy and CAR were significantly correlated with ICH size in basal ganglia patients (r-=0.36, p=0.03; r=0.43, p=0.03, respectively). CAR was significantly correlated with ICH score (r=0.33, p=0.007874). Admission VEGF levels less than 45 pg/ml had 8.4-fold increase in mortality (odds ratio [OR] 8.4545, p=0.0488). Patients with TNFα levels greater than 1.40 pg/ml had a 4.1-fold increase in mortality (OR 4.1, p=0.04)

Conclusion

Our study demonstrated that low levels (<45 pg/ml) of VEGF were associated with an 8.4-fold increase in mortality, supporting the neuroprotective effect of this protein. Elevated Hcy and CAR levels were associated with an increase in hemorrhage size in patients with basal ganglia hemorrhages. TNFα levels greater than 1.40 pg/ml were associated with a 4.1-fold increase in mortality, and this together with CAR being correlated with increased hemorrhage size and ICH score further demonstrate the inflammatory consequences after intracerebral hemorrhage. Future studies directed at lowering CRP, TNFα, and Hcy and/or increasing VEGF in intracerebral hemorrhage patients are needed and may be beneficial.

Search for Reliable Circulating Biomarkers to Predict Carotid Plaque Vulnerability

Atherosclerosis is responsible for 20% of ischemic strokes, and the plaques from the internal carotid artery the most frequently involved. Lipoproteins play a key role in carotid atherosclerosis since lipid accumulation contributes to plaque progression and chronic inflammation, both factors leading to plaque vulnerability. Carotid revascularization to prevent future vascular events is reasonable in some patients with high-grade carotid stenosis. However, the degree of stenosis alone is not sufficient to decide upon the best clinical management in some situations. In this context, it is essential to further characterize plaque vulnerability, according to specific characteristics (lipid-rich core, fibrous cap thinning, intraplaque hemorrhage). Although these features can be partly detected by imaging techniques, identifying carotid plaque vulnerability is still challenging. Therefore, the study of circulating biomarkers could provide adjunctive criteria to predict the risk of atherothrombotic stroke. In this regard, several molecules have been found altered, but reliable biomarkers have not been clearly established yet. The current review discusses the concept of vulnerable carotid plaque, and collects existing information about putative circulating biomarkers, being particularly focused on lipid-related and inflammatory molecules.

Elevated plasma high-sensitivity C-reactive protein at admission predicts the occurrence of post-stroke fatigue at 6 months after ischaemic stroke

BACKGROUND AND PURPOSE

Post-stroke fatigue (PSF) is a common neuropsychiatric affective symptom occurring after stroke. Evidence indicates activated inflammatory pathways are involved in modulating the stroke and fatigue. High-sensitivity C-reactive protein (hs-CRP) is one of the most sensitive indicators of inflammation. Our aim was to estimate the association between plasma hs-CRP and PSF after acute ischaemic stroke.

METHODS

In all, 212 acute ischaemic stroke patients were consecutively recruited within the first 14 days after stroke onset and followed up for 6 months. Plasma hs-CRP levels were assayed by enzyme linked immunosorbent assay. Fatigue severity was assessed using the Fatigue Scale for Motor and Cognitive Functions. A score ≥ 43 is defined as PSF.

RESULTS

Sixty-eight stroke patients (32.1%) were diagnosed with PSF at 6 months' follow-up. In the patients with PSF, plasma hs-CRP levels were significantly higher compared with those in non-PSF patients (t = -8.524, P ≤ 0.001). In multivariate analyses, plasma levels of hs-CRP were independently associated with PSF at 6 months (odds ratio 3.435, 95% confidence interval 2.222-5.309; P ≤ 0.001) after adjusting other recorded variables. Based on the receiver operating characteristic curve, the optimal cut-off value of plasma hs-CRP levels as an indicator for the prediction of PSF was projected to be 0.52 mg/dl, which yielded a sensitivity of 77.9% and a specificity of 74.3%, with the area under the curve 0.794 (95% confidence interval 0.725-0.864; P ≤ 0.001).

CONCLUSION

Elevated plasma hs-CRP levels at admission were associated with PSF 6 months after stroke, suggesting that these alterations might predict the development of PSF in stroke patients.

Cohort profile: BIOVASC-late, a prospective multicentred study of imaging and blood biomarkers of carotid plaque inflammation and risk of late vascular recurrence after non-severe stroke in Ireland

PURPOSE

Inflammation is important in stroke. Anti-inflammatory therapy reduces vascular events in coronary patients. ¹⁸F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) identifies plaque inflammation-related metabolism. However, long-term prospective cohort studies investigating the association between carotid plaque inflammation, identified on ¹⁸F-FDG PET and the risk of recurrent vascular events, have not yet been undertaken in patients with stroke.

PARTICIPANTS

The Biomarkers Imaging Vulnerable Atherosclerosis in Symptomatic Carotid disease (BIOVASC) study and Dublin Carotid Atherosclerosis Study (DUCASS) are two prospective multicentred observational cohort studies, employing near-identical methodologies, which recruited 285 patients between 2008 and 2016 with non-severe stroke/transient ischaemic attack and ipsilateral carotid stenosis (50%-99%). Patients underwent coregistered carotid ¹⁸F-FDG PET/CT angiography and phlebotomy for measurement of inflammatory cytokines. Plaque ¹⁸F-FDG-uptake is expressed as maximum standardised uptake value (SUV_max) and tissue-to-background ratio. The BIOVASC-Late study is a follow-up study (median 7 years) of patients recruited to the DUCASS/BIOVASC cohorts.

FINDINGS TO DATE

We have reported that ¹⁸F-FDG-uptake in atherosclerotic plaques of patients with symptomatic carotid stenosis predicts early recurrent stroke, independent of luminal narrowing. The incorporation of ¹⁸F-FDG plaque uptake into a clinical prediction model also improves discrimination of early recurrent stroke, when compared with risk stratification by luminal stenosis alone. However, the relationship between ¹⁸F-FDG-uptake and late vascular events has not been investigated to date.

FUTURE PLANS

The primary aim of BIOVASC-Late is to investigate the association between SUV_max in symptomatic 'culprit' carotid plaque (as a marker of systemic inflammatory atherosclerosis) and the composite outcome of any late major vascular event (recurrent ischaemic stroke, coronary event or vascular death). Secondary aims are to investigate associations between: (1) SUV_max in symptomatic plaque, and individual vascular endpoints (2) SUV_max in asymptomatic contralateral carotid plaque and SUV_max in ipsilateral symptomatic plaque (3) SUV_max in asymptomatic carotid plaque and major vascular events (4) inflammatory cytokines and vascular events.

Extracellular ASC exacerbated the recurrent ischemic stroke in an NLRP3-dependent manner

Using a photothrombotic mouse model of single stroke, we show that a single stroke onset increases the nuclear factor-κB (NF-κB), NLR family CARD domain containing protein 4 (NLRC4), and absent in melanoma 2 (AIM2) inflammasomes, as well as the mRNA levels of NLRP3. Next, using a photothrombotic mouse model of recurrent stroke, we found that recurrent strokes increased the activation of NLRP3, exacerbated the brain damage and the pro-inflammatory response in wild type (WT) mice, but not in NLRP3 knockout (NLRP3 KO) mice. Additionally, we found that apoptosis-associated speck-like protein containing a CARD (ASC) protein level surrounding the infarct area was comparatively increased, but that ASC specks outside of microglia in both the ipsilateral and contralateral of stroke site were decreased in NLRP3 KO mice relative to wild-type (WT) controls, and the number of ASC specks surrounding the second infarct area was positively correlated to the damage scores. Mechanistically, we found that recombinant ASC (RecASC) activated NLRP3 and induced pro-inflammatory responses, exacerbating the outcome of ischemic stroke, in WT mice, but not in NLRP3 KO mice. We therefore conclude that the NLRP3 inflammasome is activated by two attacks of stroke, which act together with ASC to exacerbate recurrent strokes.

Correlation Between Skeletal Muscle Mass Deficit and Poor Functional Outcome in Patients with Acute Ischemic Stroke

BACKGROUND AND AIMS

To date, the correlation between sarcopenia, which exists before a stroke, and acute stroke outcome remains partially understood. This study aims to evaluate the skeletal muscle mass deficit using the bioelectrical impedance analysis in patients with acute ischemic stroke.

METHODS

We enrolled 164 geriatric patients with acute ischemic stroke (108 males and 56 females) who underwent the bioelectrical impedance analysis. We evaluated clinical outcomes and their impact on patients with the skeletal muscle mass deficit determined using the skeletal muscle mass index.

RESULTS

The skeletal muscle mass deficit was obtained using the bioelectrical impedance analysis in 101 patients. Patients with the skeletal muscle mass deficit determined by the skeletal muscle mass index exhibited severe neurological impairment and functional status on admission; moreover, they tended to display poor functional outcome and prolonged hospital stay. Logistic regression analysis revealed that the skeletal muscle mass deficit remained an independent poor outcome predictor.

CONCLUSIONS

This study establishes the presence of the skeletal muscle mass deficit in over half patients with acute ischemic stroke. Furthermore, the skeletal muscle mass deficit correlates with neurological impairment owing to stroke with poorer functional prognosis.

Induction of Noninflammatory Pain in an Experimental Foot Lameness Model in Horses

The mechanism by which nonsteroidal anti-inflammatory drugs mitigate pain caused by a heart bar shoe (HBS) model of lameness is unknown. The purpose of this study was to determine if this HBS model of lameness induces inflammation in horses. Five healthy adult horses from a university teaching herd were enrolled. A custom HBS was applied to the left front foot of each horse, followed by induction of the American Association of Equine Practitioners Lameness Score of 4. Inflammatory markers including serum amyloid A (SAA) concentration, local venous tumor necrosis factor alpha and prostaglandin E2 (PGE2) concentrations, and foot temperature were measured before lameness induction and 1, 3, and 13 hours after lameness induction. Lameness induction using the HBS model did not significantly increase production of plasma SAA, tumor necrosis factor alpha, or PGE2 concentrations at measured time points. Immediately and 1 hour after lameness induction, dorsal coronary band temperatures were higher in the left front foot compared with the right front foot, but there was no difference at 3 or 13 hours. In conclusion, the HBS model did not induce inflammation as assessed by select inflammatory markers, suggesting that the HBS model induces mechanical rather than inflammatory pain. This should be considered when using the HBS model to assess analgesic drugs in horses.

Protein Cytokines, Cytokine Gene Polymorphisms, and Potential Acute Coronary Syndrome Symptoms

The purpose of this study was to determine whether relationships exist among protein cytokines, cytokine gene polymorphisms, and symptoms of potential acute coronary syndrome (ACS). Participants included 438 patients presenting to the emergency department (ED) whose symptoms triggered a cardiac evaluation (206 ruled in and 232 ruled out for ACS). Presence or absence of 13 symptoms was recorded upon arrival. Levels of tumor necrosis factor α (TNF-α), interleukin (IL)-6, and IL-18 were measured for all patients. A pilot analysis of 85 patients (ACS = 49; non-ACS = 36) genotyped eight single-nucleotide polymorphisms (SNPs; four TNF and four IL6 SNPs). Logistic regression models were tested to determine whether cytokines or SNPs predicted symptoms. Increased levels of TNF-α and IL-6 were associated with a decreased likelihood of chest discomfort for all patients. Increased levels of IL-6 were associated with a lower likelihood of chest discomfort and chest pressure for ACS patients, and an increased likelihood of shoulder and upper back pain for non-ACS patients. Elevated IL-18 was associated with an increased likelihood of sweating in patients with ACS. Of the four TNF SNPs, three were associated with shortness of breath, lightheadedness, unusual fatigue, and arm pain. In all, protein cytokines and TNF polymorphisms were associated with 11 of 13 symptoms assessed. Future studies are needed to determine the predictive ability of cytokines and related SNPs for a diagnosis of ACS or to determine whether biomarkers can identify patients with specific symptom clusters.

The mean platelet volume on admission predicts unfavorable stroke outcomes in patients treated with IV thrombolysis

Purpose

The role of biomarkers in the prediction of acute ischemic stroke (AIS) outcome or response to thrombolytic therapy (with recombinant tissue plasminogen activator [rt-PA]) remains limited. The aim of this study was to evaluate whether mean platelet volume (MPV) could predict short-term functional outcome in patients with AIS following rt-PA treatment.

Patients and methods

This was a retrospective analysis of 237 AIS patients (mean age 71.04±0.8 years, 50.6% women) consecutively admitted to a tertiary care center between 2011 and 2015.

Results

The mean MPV in the cohort was 9.8±0.35 fL (lowest tertile <7.29 fL, median 7.29–8.8 fL, and highest tertile >8.8 fL). Patients in the lowest tertile compared to median and highest tertiles were less often dependent (modified Rankin scale [mRS] ≥3) at admission (87.2% vs 96.1% and 96.1%, respectively, P=0.04) and less often had a poor stroke outcome (mRS 4–6) at discharge (28.2% vs 55.3% and 44.7%, P<0.01). However, there was no significant difference between tertiles with regard to AIS etiology, CT (Alberta Stroke Program Early CT) score, frequency of stroke due to large artery occlusion, risk of secondary hemorrhage, and early neurologic deterioration. Multivariable analysis after adjustment for confounders showed that patients in the second and third tertiles had a significantly higher risk of poor stroke outcome (OR =1.9, 95% CI =1.01–4), lack of early improvement (OR =1.91, 95% CI =1.05–3.47), lower chance of good outcome (mRS 0–2; OR =0.38, 95% CI =0.18–0.78), or minor stroke at discharge (OR =0.47, 95% CI =0.26–0.84). Receiver operating characteristic analysis for prediction of poor stroke outcome showed that the optimal cut-off point of MPV was 8.8 fL (area under the curve 0.586 [0.512–0.659], P=0.03) with a sensitivity of 82.7% and a specificity of 43.9%.

Conclusion

Disabling or fatal ischemic stroke in thrombolyzed patients was observed more often in patients with high admission MPV. The prognostic value of MPV was independent of other well-defined individual risk factors.

NK cells in cerebral ischemia

As a vital cell type in immune system and infiltrating cells in ischemic brain, NK cells can bridge the crosstalk between immune system and nervous system in stroke setting. The mechanism of action of NK cells is complicated, involving direct and indirect actions. NK cells are closely associated with poststroke inflammation, immunodepression and infections. The excessive inflammatory response in ischemic brain is one of the important causes for aggravating cerebral ischemic injury. Besides the inflammation induced by ischemia itself, thrombolytic drug tissue plasminogen activator (tPA) administration could also induce deteriorative inflammation, which is unfavorable for stroke control and recovery. Regulating NK cells may has the potential to modulate the immune response, limiting the development of ischemic damage and getting better outcome. In addition, post-stroke immunosuppression may lead to infections which contribute to higher severity and mortality of ischemic stroke (IS). Targeting NK cells may help to find novel pathways for IS therapy, which can both ameliorate the infarction itself, but also reduce the infectious complications. NK cells may also link IS and related diseases, suggesting NK cells can be used as a diagnostic or prognostic biomarker for IS prevention and treatment.

Inflammatory Markers and Severity of Intracerebral Hemorrhage

Background and purpose

The pathogenesis of brain injury after intracerebral hemorrhage is thought to be due to mechanical damage followed by ischemic, cytotoxic, and inflammatory changes in the underlying and surrounding tissue.In recent years, there has been a greater research interest into the various inflammatory biomarkers and growth factors that are secreted during intracerebral hemorrhage. The biomarkers investigated in this study are tumor necrosis factor alpha (TNF alpha), C-reactive protein (CRP), homocysteine (Hcy), and vascular endothelial growth factor (VEGF). The aim of this study was to further investigate the effects of these biomarkers in predicting the acute severity outcome of intracerebral hemorrhage (ICH).

Methods

We conducted a retrospective chart review of patients with spontaneous ICH with TNF alpha, CRP, VEGF, and Hcy levels drawn on admission. Forty-two patients with spontaneous ICH with at least one of the above labs were included in the study. Primary outcomes included death, Glasgow Coma Scale (GCS) on admission, early neurologic decline (END), and hemorrhage size. Secondary outcomes included GCS on discharge, ICH score, functional outcome risk stratification scale of intracerebral hemorrhage (FUNC score), change in hemorrhage size, need for surgical intervention, and length of intensive care unit (ICU) stay.

Results

Forty-two patients with spontaneous intracerebral hemorrhage (ICH) were analyzed, 12 patients (28.5%) required surgical intervention, and four patients (9.5%) died. Only low VEGF serum values were found to predict mortality. TNF alpha, CRP, Hcy, and VEGF levels in our patients with ICH were not found to predict early neurologic decline and were not correlated with GCS on admission, initial hemorrhage size, change in hemorrhage size, need for surgical intervention, ICH score, FUNC score, midline shift, and length of ICU stay. CRP and Hcy were elevated in 58% and 31% of patients tested, respectively. GCS on admission and ICH score were significantly associated with mortality.

Conclusion

After careful statistical review of the data obtained from this patient population, only low VEGF values were found to be a significant predictor of mortality. However, elevated CRP and Hcy levels were associated with a non-significant trend in hemorrhage size and mortality suggesting that CRP and Hcy-lowering therapies may decrease hemorrhagic stroke risk and severity.

Inflammatory Profiles of the Interleukin Family and Network in Cerebral Hemorrhage

Cerebral hemorrhage is a series of devastating cerebrovascular diseases with high mortality, morbidity and recurrence rate. Localized and systemic immuno-reactions are involved. Aggregation of immunocytes, which were both recruited from the peripheral circulation and resident in the central nervous system, is induced and activated by hematoma-related blood components. Subsequently, various cytokines, chemokines, free radicals and toxic chemicals are secreted to participant host defense responses. Among these, neuro-inflammation plays critical roles in both the pathologic processes of secondary injuries and recovery of neural damages. Numerous treatment strategies have been proposed, aiming at controlling the balance between anti- and proinflammation. Here, we summarized our current understanding and potential clinical applications for cytokines of the interleukin family in the pathogenesis of hemorrhagic stroke. In addition, we conducted protein-protein network, gene ontology and KEGG analysis on the interleukins using online bioinformatic tools to further elaborate the comprehensive mechanisms of interleukins in cerebral hemorrhage.

Rheumatoid arthritis significantly increased recurrence risk after ischemic stroke/transient ischemic attack

The effect of RA on recurrent stroke is unknown. Therefore, we examined effects of rheumatoid arthritis (RA) on risk of stroke recurrence and investigated the interaction between RA and traditional cardiovascular risk factors on recurrence risk after ischemic stroke (IS) or transient ischemic attack (TIA). Of 3190 patients with IS or TIA recruited in this cohort study, 638 were comorbid with RA and 2552 without RA. Stroke recurrence, RA, lifestyle, lipid variables and other comorbidities were identified through linkage between a nationwide stroke database in Taiwan and the National Health Insurance claims database. Cox proportional hazard models with competing risk adjustment were used to evaluate the relationship between RA and recurrent stroke. Patients with RA showed a significantly increased risk of recurrent stroke, particular in recurrent IS/TIA. The increased risk of recurrent IS/TIA in RA patients may through the changes of triglycerides (TG)/high-density lipoprotein cholesterol (HDL-C) ratio. A positive additive interaction was observed between RA and current smoking on the risk of recurrent IS/TIA. Significantly increased risks for recurrent IS/TIA were observed among RA patients who smoked > 40 years or those who smoked > 20 cigarettes/day. This study provides the first evidence that RA significantly increased recurrence IS/TIA risk. The changes of TG/HDL-C ratio may play some roles in the recurrence IS/TIA risk in RA patients. In addition, our results suggest that smoking increases the risk of recurrent IS/TIA in RA patients and reinforces the need for aggressive smoking cessation efforts in RA patients.