20-Hydroxyeicosatetraenoic Acid as a Predictor of Neurological Deterioration in Acute Minor Ischemic Stroke

Influence of hyperbaric oxygen therapy-specialized care on limb motor function and mental state of cerebral infarction patients with hemiplegia

BACKGROUND

Currently, cerebral infarction (CI) is mainly treated by emergency craniotomy or conservative treatment. However, some studies have questioned the functional recovery of patients after hyperbaric oxygen therapy (HBOT)-specialized care.

OBJECTIVE

This paper mainly explores the influence of HBOT-specialized care on limb motor function (LMF) and mental state of CI patients with hemiplegia.

METHODS

The medical records of 113 CI patients with hemiplegia treated in our hospital from March 2020 to March 2022 were collected. Of these, 53 received routine care nursing (conventional group) and 60 cases were given HBOT-specialized care (research group). Patient general data, scores of Fugl-Meyer Assessment (FMA), National Institutes of Health Stroke Scale (NIHSS), Self-rating Anxiety/Depression Scale (SAS/SDS) and Barthel Index (BI), and nursing efficiency were comparatively analyzed.

RESULTS

The two groups showed comparability in general data. FMA and BI scores were increased in the research group after rehabilitation treatment, higher than the baseline and those of the conventional group, while NIHSS, SAS, and SDS scores were reduced, lower compared with baseline and those of the conventional group. In addition, significantly higher nursing efficiency was determined in the research group.

CONCLUSION

HBOT-specialized care has beneficial effects on LMF, mental state, negative emotions and self-care ability of CI patients with hemiplegia and can enhance nursing efficacy, which deserves clinical popularization.

Factors related to dietary quality among older stroke high-risk population in Tianjin community, China: a multicenter study

BACKGROUND

Stroke is a common and frequently-occurring disease in older people. It has the characteristics of high morbidity, high mortality, high recurrence rate and high disability rate. Most stroke risk studies are based on pathophysiology, however psychosocial factors such as diet quality are often understudied. The aim of this study was to assess stroke risk in urban community residents in Tianjin and investigate the factors that affect the dietary quality of older stroke high-risk populations.

METHODS

Using a cross-sectional, multicenter study, recruit people aged 60 to 80 in Tianjin. Dietary intake data were obtained through a validated food frequency questionnaire, which were used to calculate Alternate Healthy Eating Index-2010 (AHEI-2010) and to analyze its association with sociodemographic characteristics, stroke risk factors and health marker variables.

RESULTS

A total of 1068 participants from 4 community health service centers in Tianjin were recruited, including 300 low-risk individuals and 768 high-risk individuals. Compared with the low-risk group (62.75 ± 3.59), the AHEI-2010 mean score of the high-risk group (56.83 ± 6.54) was significantly lower. The top three most common risk factors among participants were dyslipidemia (80.3%), hypertension (60.6%), and physical inactivity (58.2%). Multiple logistic regression showed that diet quality was independently and significantly associated with stroke risk (OR = 0.765; 95%CI: 0.690-0.848, p < 0.001).

CONCLUSION

The diet quality of high-risk stroke population in Tianjin is far from ideal. At the same time, public health knowledge needs to be disseminated and educated, especially among those at high risk of cerebrovascular disease, with a focus on improving psychosocial factors such as diet quality.

Mice deficient for G-protein-coupled receptor 75 display altered presynaptic structural protein expression and disrupted fear conditioning recall

There are a number of G-protein-coupled receptors (GPCRs) that are considered "orphan receptors" because the information on their known ligands is incomplete. Yet, these receptors are important targets to characterize, as the discovery of their ligands may lead to potential new therapies. GPR75 was recently deorphanized because at least two ligands appear to bind to it, the chemokine CCL5 and the eicosanoid 20-Hydroxyeicosatetraenoic acid. Recent reports suggest that GPR75 may play a role in regulating insulin secretion and obesity. However, little is known about the function of this receptor in the brain. To study the function of GPR75, we have generated a knockout (KO) mouse model of this receptor and we evaluated the role that this receptor plays in the adult hippocampus by an array of histological, proteomic, and behavioral endpoints. Using RNAscope® technology, we identified GPR75 puncta in several Rbfox3-/NeuN-positive cells in the hippocampus, suggesting that this receptor has a neuronal expression. Proteomic analysis of the hippocampus in 3-month-old GPR75 KO animals revealed that several markers of synapses, including synapsin I and II are downregulated compared with wild type (WT). To examine the functional consequence of this down-regulation, WT and GPR75 KO mice were tested on a hippocampal-dependent behavioral task. Both contextual memory and anxiety-like behaviors were significantly altered in GPR75 KO, suggesting that GPR75 plays a role in hippocampal activity.

Serum neurofilament light chain levels are associated with early neurological deterioration in minor ischemic stroke

Objectives

Patients with minor ischemic stroke (MIS) frequently suffer from early neurological deterioration (END) and become disabled. Our study aimed to explore the association between serum neurofilament light chain (sNfL) levels and END in patients with MIS.

Methods

We conducted a prospective observational study in patients with MIS [defined as a National Institutes of Health Stroke Scale (NIHSS) score 0–3] admitted within 24 h from the onset of symptoms. sNfL levels were measured at admission. The primary outcome was END, defined as an increase in the NIHSS score by ≥2 points within 5 days after admission. Univariate and multivariate analyses were performed to explore the risk factors associated with END. Stratified analyses and interaction tests were conducted to identify variables that might modify the association between sNfL levels and END.

Results

A total of 152 patients with MIS were enrolled, of which 24 (15.8%) developed END. The median sNfL level was 63.1 [interquartile range (IQR), 51.2–83.4] pg/ml on admission, which was significantly higher than that of 40 age- and sex-matched healthy controls (median 47.6, IQR 40.8–56.1 pg/ml; p &lt; 0.001). Patients with MIS with END had a higher level of sNfL (with ND: median 74.1, IQR 59.5–89.8 pg/ml; without END: median 61.2, IQR 50.5–82.2 pg/ml; p = 0.026). After adjusting for age, baseline NIHSS score, and potential confounding factors in multivariate analyses, an elevated sNfL level (per 10 pg/mL) was associated with an increased risk of END [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.04–1.77; p = 0.027). Stratified analyses and interaction tests demonstrated that the association between sNfL and END did not change by age group, sex, baseline NIHSS score, Fazekas' rating scale, hypertension, diabetes mellitus, intravenous thrombolysis, and dual antiplatelet therapy in patients with MIS (all p for interaction &gt; 0.05). END was associated with an increased risk of unfavorable outcomes (modified Rankin scale score ranging from 3 to 6) at 3 months.

Conclusion

Early neurological deterioration is common in minor ischemic stroke and is associated with poor prognosis. The elevated sNfL level was associated with an increased risk of early neurological deterioration in patients with minor ischemic stroke. sNfL might be a promising biomarker candidate that can help to identify patients with minor ischemic stroke at high risk of neurological deterioration, for reaching individual therapeutic decisions in clinical practice.

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.

Prevalence and Risk Factors of High-Risk Population for Stroke: A Population-Based Cross-Sectional Survey in Southwestern China

With the aging of the population and the change of lifestyle in China, the prevalence and risk factors of the high-risk population for stroke may change. However, few studies performed community-based high-risk stroke population surveys in China. Hence, we performed this multicenter, cross-sectional, and community-based survey in Sichuan of southwestern China, according to the China National Stroke Screening Survey (CNSSS) program in 2015. The residents aged ≥ 40 years volunteered to participate in the face-to-face survey in 8 communities in Sichuan. The 8 communities were selected using the cluster randomization method. Subjects with at least three of the eight stroke-related risk factors were classified as a high-risk population for stroke. Otherwise were classified as a low-risk population for stroke. Furthermore, 1,011 individuals were randomly selected among the low-risk population for stroke as controls. Among 16,892 participants, 2,369 (14.0%) were high-risk population for stroke. After full adjustments, all eight risk factors for stroke were significantly associated with the high-risk population for stroke (P < 0.001). The largest contributor was hypertension [population-attributable risk (PAR) 28.4%], followed by physical inactivity (PAR 14.2%), dyslipidemia (PAR 11.2%), overweight/obesity (PAR 9.4%), diabetes (PAR 7.2%), family history (PAR 6.8%), smoking (PAR 5.9%), and atrial fibrillation (PAR 3.5%). Carotid atherosclerosis was more serious in the high-risk population for stroke than in controls (P < 0.05). The prevalence of the high-risk population for stroke was high in southwestern China. Hypertension, physical inactivity, and dyslipidemia were stronger contributors for the high-risk population for stroke. Individual-level and population-level interventions for these leading risk factors are very important for the primary prevention of stroke.

20-HETE Participates in Intracerebral Hemorrhage-Induced Acute Injury by Promoting Cell Ferroptosis

Intracerebral hemorrhage (ICH) is a highly fatal type of stroke that leads to various types of neuronal death. Recently, ferroptosis, a form of cell death resulting from iron-dependent lipid peroxide accumulation, was observed in a mouse ICH model. N-hydroxy-N'-(4-n-butyl-2-methylphenyl)-formamidine (HET0016), which inhibits synthesis of the arachidonic acid metabolite 20-hydroxyeicosatetraenoic acid (20-HETE), has shown a protective effect after ICH. However, the underlying mechanisms of the neuroprotective effect need further investigation. We explored whether 20-HETE participates in ICH-induced ferroptosis ex vivo by using hemoglobin-treated organotypic hippocampal slice cultures (OHSCs) and in vivo by using a collagenase-induced ICH mouse model. Ex vivo, we found that the 20-HETE synthesis inhibitor HET0016 and antagonist 20-6,15-HEDGE reduced hemoglobin-induced cell death, iron deposition, and lipid reactive oxygen species levels in OHSCs. Furthermore, 20-HETE inhibition in OHSCs increased the expression of glutathione peroxidase (GPX) 4, an antioxidant enzyme that serves as a main regulator of ferroptosis. In contrast, exposure of OHSCs to the 20-HETE stable mimetic 20-5,14-HEDGE induced cell death that was significantly inhibited by the ferroptosis inhibitor ferrostatin-1. In vivo, HET0016 treatment ameliorated focal deficits, reduced lesion volume, and decreased iron accumulation around the lesion at day 3 and 7 after ICH. In addition, lipid peroxidation was decreased and expression of GPX4 was increased in the HET0016-treated ICH group. The mitogen-activated protein kinase pathway also was inhibited by HET0016 in vivo. These results indicate that 20-HETE contributes to ICH-induced acute brain injury in part by activating ferroptosis pathways, thereby providing an upstream target for inhibiting ferroptosis.

20-hydroxyeiscosatetraenoic acid may be as a predictor of malignant middle cerebral artery infarction in patients with massive middle cerebral artery infarction

Background

Early identification of massive middle cerebral artery infarction (MCAI) at risk for malignant MCAI (m-MCAI) may be useful in selecting patients for aggressive therapies. The aim of this study was to determine whether CYP metabolites may help to predict impending m-MCAI.

Methods

This is a prospective, two-center observational study in 256 patients with acute massive MCAI. Plasma levels of 20-hydroxyeicosatetraenoic acid (20-HETE), epoxyeicosatrienoic acids, and dihydroxyeicosatrienoic acids were measured at admission. Brain computed tomography (CT) was performed at admission and repeated between day 3 and 7, or earlier if there was neurological deterioration. The primary outcome was m-MCAI. The m-MCAI was diagnosed when follow-up brain CT detected a more than two-thirds space-occupying MCAI with midline shift, compression of the basal cisterns, and neurological worsening.

Results

In total of 256 enrolled patients, 77 (30.1%) patients developed m-MCAI. Among the 77 patients with m-MCAI, 60 (77.9%) patients died during 3 months of stroke onset. 20-HETE level on admission was significantly higher in patients with m-MCAI than those without m-MCAI. There was an increase in the risk of m-MCAI with increase of 20-HETE levels. The third and fourth quartiles of 20-HETE levels were independent predictors of m-MCAI (OR: 2.86; 95% CI: 1.16 – 6.68; P = 0.025, and OR: 4.23; 95% CI: 1.35 – 8.26; P = 0.002, respectively).

Conclusions

Incidence of m-MCAI was high in patients with massive MCAI and the prognosis of m-MCAI is very poor. Elevated plasma 20-HETE may be as a predictor for m-MCAI in acute massive MCAI, and it might useful in clinical practice in therapeutic decision making.

Increased 20-HETE Signaling Suppresses Capillary Neurovascular Coupling After Ischemic Stroke in Regions Beyond the Infarct

Neurovascular coupling, the process by which neuronal activity elicits increases in the local blood supply, is impaired in stroke patients in brain regions outside the infarct. Such impairment may contribute to neurological deterioration over time, but its mechanism is unknown. Using the middle cerebral artery occlusion (MCAO) model of stroke, we show that neuronal activity-evoked capillary dilation is reduced by ∼75% in the intact cortical tissue outside the infarct border. This decrease in capillary responsiveness was not explained by a decrease in local neuronal activity or a loss of vascular contractility. Inhibiting synthesis of the vasoconstrictive molecule 20-hydroxyeicosatetraenoic acid (20-HETE), either by inhibiting its synthetic enzyme CYP450 ω-hydroxylases or by increasing nitric oxide (NO), which is a natural inhibitor of ω-hydroxylases, rescued activity-evoked capillary dilation. The capillary dilation unmasked by inhibiting 20-HETE was dependent on PGE2 activation of endoperoxide 4 (EP4) receptors, a vasodilatory pathway previously identified in healthy animals. Cortical 20-HETE levels were increased following MCAO, in agreement with data from stroke patients. Inhibition of ω-hydroxylases normalized 20-HETE levels in vivo and increased cerebral blood flow in the peri-infarct cortex. These data identify 20-HETE-dependent vasoconstriction as a mechanism underlying capillary neurovascular coupling impairment after stroke. Our results suggest that the brain's energy supply may be significantly reduced after stroke in regions previously believed to be asymptomatic and that ω-hydroxylase inhibition may restore healthy neurovascular coupling post-stroke.

Stroke risk and its association with quality of life: a cross-sectional study among Chinese urban adults

BACKGROUND

Stroke is a leading cause of mortality and disability worldwide. Most stroke risk studies focused on more established biological and pathophysiological risk factors such as hypertension and smoking, psychosocial factors such as quality of life are often under-investigated and thus less reported. The current study aims to estimate stroke risk and explore the impact of quality of life on stroke risk among a community sample of urban residents in Shanghai.

METHODS

This cross-sectional study was conducted in Fengxian District of Shanghai City from December 2018 to April 2019. 4030 representative participants were recruited through a multistage, stratified, probability proportional to size sampling method and completed the study. Stroke risk was assessed using the Rapid Stroke Risk Screening Chart that included 8 risk factors for stroke. Quality of life was measured using the World Health Organization Quality of Life-brief version (WHOQOL-BREF).

RESULTS

One-third of residents were at risk for stroke, including 14.39% at high risk, and 18.68% at middle risk. The top three most commonly reported risk factors were physical inactivity (37.30%), hypertension (25.38%), and smoking (17.32%). Quality of life and its four domains were all independently and significantly associated with stroke risk. Multinominal logistic regressions showed that a one-unit increase in the quality of life was associated with a decreased relative risk for middle-risk relative to low-risk of stroke by a factor of 0.988 (95% CI:0.979, 0.997, P = 0.007), and a decreased relative risk for high-risk relative to low-risk of stroke by a factor of 0.975 (95% CI:0.966, 0.984, P < 0.001).

CONCLUSIONS

Our findings showed an alarmingly high prevalence of stroke risk among the sample, which may require future intervention programs to focus on improving both biological and behavioral risk factors such as increasing physical activity, early diagnosis and treatment of hypertension, and smoking cessation, as well as improving psychosocial factors such as quality of life.

Personalized antiplatelet therapy based on clopidogrel/aspirin resistance tests in acute ischemic stroke and transient ischemic attack: Study protocol of a multi-center, single-blinded and randomized controlled trial

BACKGROUND

Clopidogrel and aspirin are key intervention for acute ischemic stroke (AIS) and transient ischemic attack (TIA). However, with increased clinical application, many patients have shown clopidogrel resistance (CR) and/or aspirin resistance (AR) that affect antiplatelet therapy on AIS/TIA. At present, there is no research reported on personalized antiplatelet therapy guidelines for patients with CR and/or AR. Our study aims to assess the effect of personalized antiplatelet therapy based on CYP2C19 genotype and urine 11-dhTxB2 tests in patients with AIS or TIA.

METHODS

This is a multi-center randomized controlled trial. Eligible patients with AIS/TIA from 14 comprehensive hospitals in Jiangxi province will be recruited after obtaining informed consent. Participants will be randomly divided into the intervention group and the control group at a ratio of 1:1. personalized antiplatelet therapy based on the CYP2C19 genotype/urine11-dhTxB2 tests will be given to the intervention group. Demographics, disease history, laboratory investigations, therapys, physiological tests, imaging reports and other clinical features will be collected. Clinical outcomes including stroke recurrence, Modified Rankin Scale (mRS) score, bleeding events and all-cause mortality will be assessed at the 1st, 3rd, 6th, and 12th-month post-discharge.

DISCUSSION

Our study will conduct free antiplatelet resistance tests and personalized antiplatelet therapy for AIS/TIA patients with CR/AR, ultimately evaluating personalized therapy effectiveness through one-year follow-up. The research results will help to assess the impact of personalized antiplatelet therapy on the prognosis of stroke, thus providing reference for precise clinical treatment.

Interactions among variants in P53 apoptotic pathway genes are associated with neurologic deterioration and functional outcome after acute ischemic stroke

OBJECTIVE

Neurologic deterioration (ND) and functional outcome after ischemic stroke (IS) are not accurately predicted by clinical pictures on admission. The aim of present study was to investigate the association of variants in P53 apoptotic pathway genes with ND and functional outcome after IS.

METHODS

Genotypes of nine variants in apoptosis-relevant genes were measured in patients with acute IS. Gene-gene interactions were analyzed by generalized multifactor dimensionality reduction (GMDR). The primary outcome was ND. ND was diagnosed in patients who worsened ≥2 points (National Institutes of Health Stroke Scale [NIHSS] score) within the first 10 days of stroke onset. The secondary outcome was functional status at 90 days after IS as measured by modified Rankin Scale (mRS) score.

RESULTS

A total of 705 enrolled patients, ND occurred in 174 (24.7%) patients, and 184 (26.1%) patients were poor functional outcome (mRS score > 2). Although the nine variants were not significantly associated with ND and functional outcome by univariate analysis, there was a gene-gene interaction among P53rs1042522, MDM-2rs2279744, and MMP-9 rs3918242 using GMDR analysis. The high-risk interaction among the three variants was independently associated with higher risk of ND (HR, 2.04, 95% CI: 1.22-5.64, p = .018) and poor functional outcome (OR, 2.68, 95% CI: 1.68-7.86, p = .004) after adjusting for the covariates.

CONCLUSION

The interactions among P53 rs1042522, MDM-2 rs2279744, and MMP-9 rs3918242 may increase the risk of ND and poor functional outcome and may be considered as a genetic marker of predicting ND and poor functional outcome after stroke.

Does CYP2C19 polymorphisms affect neurological deterioration in stroke/TIA patients?: A systematic review and meta-analysis of prospective cohort studies

BACKGROUND

The association between cytochrome P450 2C19 (CYP2C19) polymorphisms and neurological deterioration in stroke or transient ischemic attack (TIA) patients is not completely understood. Hence, we performed a systematic review and meta-analysis of prospective cohort studies to quantify this association.

METHODS

PubMed, Cochrane Library, Excerpta Medica Database, China National Knowledge Infrastructure and WanFang databases were searched for studies published up to April 2019. Prospective cohort studies that reported an association between CYP2C19 polymorphisms and neurological deterioration in stroke/TIA patients were included. Data on risk ratio (RR) and 95% confidence intervals (CI) were extracted and pooled by the authors. Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines were followed.

RESULTS

Twelve eligible studies were included. Twelve studies reported CYP2C19∗2, ∗3 loss-of-function alleles and 5 studies reported CYP2C19∗17 gain-of-function allele. Compared to non-carriers, carriers of CYP2C19∗2, ∗3 loss-of-function alleles had a significantly higher risk of neurological deterioration (RR, 1.63; 95%CI, 1.32-2.02). Conversely, carriers of CYP2C19∗17 gain-of-function allele had a significantly lower risk of neurological deterioration (RR, 0.520; 95%CI, 0.393-0.689) compared to non-carriers.

CONCLUSIONS

This meta-analysis demonstrated that the carriers of CYP2C19∗2, ∗3 loss-of-function alleles have an increased risk of neurological deterioration compared to non-carriers in stroke or TIA patients. Additionally, CYP2C19∗17 gain-of-function allele can reduce the risk of neurological deterioration.

The Value of Combined Detection of D-dimer and CD62p in Judging the Severity of Acute Cerebral Infarction and Short-Term Prognosis

Objective

To explore the value of combined detection of peripheral blood P-selectin (CD62p) and D-dimer (D-dimer) in the judgment of acute cerebral infarction severity and short-term prognosis.

Methods

268 patients with acute cerebral infarction from February 2015 to February 2019 were selected as the observation group. According to the National Institute of Health stroke scale, there were 90 cases (SCI group), 88 cases (MOCI group), and 90cases (MICI group) in the severe, moderate, and mild cerebral infarction groups, respectively. In the same period, 80 cases of healthy people served as the Normal group. Use flow cytometry to detect CD62p in peripheral blood and magnetic bead method to detect D-dimer level within 24 hours of onset. Logistic regression was used to analyze whether the two are factors affecting the short-term prognosis of acute cerebral infarction, and the ROC curve was drawn to evaluate the value of the combined detection of the two in the short-term prognosis of patients with acute cerebral infarction.

Results

Peripheral blood D-dimer and CD62p levels (2.95 ± 0.76 ng/l, 34.03 ± 5.29 ng/l) in the SCI group were higher than those in the MOCI group (2.30 ± 0.51 ng/l, 27.58 ± 5.56 ng/l) and the MICI group (1.87 ± 0.40 ng/l, 19.60 ± 3.98 ng/l); the difference between the groups was statistically significant (P < 0.05). Logistic regression analysis showed that D-dimer and CD62p were independent risk factors affecting the poor prognosis of patients with acute cerebral infarction (OR values were 3.752 and 1.213, and 95% CI were 1.612-7.934 and 1.093-1.342, respectively, both P < 0.05). The AUC of D-dimer combined with CD62p for predicting poor prognosis of acute cerebral infarction is 0.859, which is better than D-dimer and CD62p alone.

Conclusion

Peripheral blood D-dimer combined with CD62p detection is helpful for the risk stratification and short-term prognosis assessment of patients with acute cerebral infarction. Clinical detection is of great significance for the prevention and monitoring of disease development.

The Relationship between the Mean Platelet Volume and Carotid Atherosclerosis and Prognosis in Patients with Acute Cerebral Infarction

Objective

To investigate the relationship between mean platelet volume (MPV) level and carotid atherosclerosis and prognosis in patients with acute cerebral infarction. Methods. A retrospectively included 160 patients with acute cerebral infarction classified by TOAST classification as aortic atherosclerosis as the observation group. To analyze the relationship between MPV and carotid atherosclerosis, and use receiver operating characteristic (ROC) curves to analyze the role of MPV in predicting the prognosis of acute cerebral infarction in the observation group, grouping patients with different MPV by cut-off value, and analyze the differences in factors between the two groups of patients.

Results

MPV has a positive correlation with carotid atherosclerosis in patients with acute cerebral infarction. Multivariate logistic regression analysis revealed that increased MPV was an independent predictor of poor functional outcome in patients with acute cerebral infarction (Odds Ratio (OR): 6.152, 95% CI: 2.385-13.625, P < 0.01). ROC curve analysis showed that the area under the curve for MPV to predict poor prognosis was 0.868 (95% CI: 0.787-949, P < 0.01). The cutoff value, sensitivity, and specificity were 12.65, 76.2%, and 87.6%. Compared with patients with MPV < 12.65 at admission, patients with higher MPV levels (MPV ≥ 12.65) at admission have larger infarct size, more severe carotid artery stenosis, poor short-term prognosis, and higher mortality.

Conclusion

MPV level is closely related to the degree of carotid atherosclerosis in patients with acute cerebral infarction, and it is also an independent predictor of poor prognosis in patients with acute cerebral infarction at 3 months.

20-HETE synthesis inhibition attenuates traumatic brain injury-induced mitochondrial dysfunction and neuronal apoptosis via the SIRT1/PGC-1α pathway: A translational study

Objectives

20‐hydroxyeicosatetraenoic acid (20‐HETE) is a metabolite of arachidonic acid catalysed by cytochrome P450 enzymes and plays an important role in cell death and proliferation. We hypothesized that 20‐HETE synthesis inhibition may have protective effects in traumatic brain injury (TBI) and investigated possible underlying molecular mechanisms.

Materials and methods

Neurologic deficits, and lesion volume, reactive oxygen species (ROS) levels and cell death as assessed using immunofluorescence staining, transmission electron microscopy and Western blotting were used to determine post‐TBI effects of HET0016, an inhibitor of 20‐HETE synthesis, and their underlying mechanisms.

Results

The level of 20‐HETE was found to be increased significantly after TBI in mice. 20‐HETE synthesis inhibition reduced neuronal apoptosis, ROS production and damage to mitochondrial structures after TBI. Mechanistically, HET0016 decreased the Drp1 level and increased the expression of Mfn1 and Mfn2 after TBI, indicating a reversal of the abnormal post‐TBI mitochondrial dynamics. HET0016 also promoted the restoration of SIRT1 and PGC‐1α in vivo, and a SIRT1 activator (SRT1720) reversed the downregulation of SIRT1 and PGC‐1α and the abnormal mitochondrial dynamics induced by 20‐HETE in vitro. Furthermore, plasma 20‐HETE levels were found to be higher in TBI patients with unfavourable neurological outcomes and were correlated with the GOS score.

Conclusions

The inhibition of 20‐HETE synthesis represents a novel strategy to mitigate TBI‐induced mitochondrial dysfunction and neuronal apoptosis by regulating the SIRT1/PGC‐1α pathway.

1-Trifluoromethoxyphenyl-3-(1-Propionylpiperidin-4-yl) Urea Protects the Blood-Brain Barrier Against Ischemic Injury by Upregulating Tight Junction Protein Expression, Mitigating Apoptosis and Inflammation In Vivo and In Vitro Model

We previously have revealed that 1-trifluoromethoxyphenyl-3-(1- propionylpiperidin-4-yl) urea (TPPU), as a soluble epoxide hydrolase (sEH) inhibitor can reduce infarct volume, protect blood-brain barrier (BBB) and brain against ischemic injury in rats. Here, we investigated the potential mechanisms of TPPU on BBB integrity in both in permanent middle cerebral artery occlusion (pMCAO) rat model and in oxygen-glucose deprivation/reperfusion (OGD/R)-induced human brain microvascular endothelial cells (HBMVECs) model. In pMCAO rat, TPPU administration decreased brain edema and Evans blue content, increased tight junction proteins (TJs) expression of claudin-5, occludin, and zonula occludens-1 (ZO-1). In OGD/R model, OGD/R significantly increased permeability and cell apoptosis, downregulated the expression of claudin-5, ZO-1, occludin, and lymphoma (Bcl)-2. Notably, TPPU pretreatment effectively protected the BBB integrity by reducing the permeability, promoting expression of claudin-5, ZO-1, occluding and Bcl-2, mitigating reactive oxygen species (ROS) injury and release of interleukin-1β (IL-1β), IL-6β, and tumor necrosis factor-α (TNF-α), downregulating expression of matrix metalloproteinase-9 (MMP-9), MMP-2, bcl-2-associated X protein (Bax), IL-1β, IL-6β, and TNF-α. Moreover, OGD/R induced the up-regulation of p-p65, p-IκB, and p-p38, which were effectively decreased after TPPU pretreatment in comparison with that of the OGD/R group. Furthermore, pyrrolidinedithiocarbamate (PDTC, a selective inhibitor of NF-κB p65) not only alleviated the OGD/R-induced HBMVECs injury and permeability, but also reduced the expression of TNF-α, IL-6, IL-1β, p-p65, and p-IκB, and the protective effect of PDTC was equivalent to that of TPPU. These results indicate that TPPU protects BBB integrity against ischemic injury by multiple protective mechanisms, at least in part, by reducing ROS, inflammation, apoptosis, and suppressing the nuclear factor-κB (NF-κB) and p38 signaling pathways.

Lipids and Lipid Mediators Associated with the Risk and Pathology of Ischemic Stroke

Stroke is a severe neurological disorder in humans that results from an interruption of the blood supply to the brain. Worldwide, stoke affects over 100 million people each year and is the second largest contributor to disability. Dyslipidemia is a modifiable risk factor for stroke that is associated with an increased risk of the disease. Traditional and non-traditional lipid measures are proposed as biomarkers for the better detection of subclinical disease. In the central nervous system, lipids and lipid mediators are essential to sustain the normal brain tissue structure and function. Pathways leading to post-stroke brain deterioration include the metabolism of polyunsaturated fatty acids. A variety of lipid mediators are generated from fatty acids and these molecules may have either neuroprotective or neurodegenerative effects on the post-stroke brain tissue; therefore, they largely contribute to the outcome and recovery from stroke. In this review, we provide an overview of serum lipids associated with the risk of ischemic stroke. We also discuss the role of lipid mediators, with particular emphasis on eicosanoids, in the pathology of ischemic stroke. Finally, we summarize the latest research on potential targets in lipid metabolic pathways for ischemic stroke treatment and on the development of new stroke risk biomarkers for use in clinical practice.

Variants in clopidogrel-relevant genes and early neurological deterioration in ischemic stroke patients receiving clopidogrel

BACKGROUND

Early neurological deterioration (END) is common in acute ischemic stroke (IS). However, the underlying mechanisms for END are unclear. The aim of this study was to evaluate the associations of 16 variants in clopidogrel-relevant genes and interactions among these variants with END in acute IS patients receiving clopidogrel treatment.

METHODS

We consecutively enrolled 375 acute IS patients between June 2014 and January 2015. Platelet aggregation was measured on admission and after the 7-10 days of clopidogrel treatment. The 16 variants in clopidogrel-relevant genes were examined using mass spectrometry. The primary outcome was END within the 10 days of admission. Gene-gene interactions were analyzed by generalized multifactor dimensionality reduction (GMDR) methods.

RESULTS

Among the 375 patients, 95 (25.3%) patients developed END within the first 10 days of admission. Among the 16 variants, only CYP2C19*2 (rs4244285) AA/AG was associated with END using single-locus analytical approach. GMDR analysis revealed that there was a synergistic effect of gene-gene interactions among CYP2C19*2 rs4244285, P2Y12 rs16863323, and GPIIIa rs2317676 on the risk for END. The high-risk interactions among the three variants were associated with the higher platelet aggregation and independent predictor for END after adjusting for the covariates (hazard ratio: 2.82; 95% confidence interval: 1.36-7.76; P = 0.003).

CONCLUSIONS

END is very common in patients with acute IS. The mechanisms leading to END are most likely multifactorial. Interactions among CYP2C19*2 rs4244285, P2Y12 rs16863323, and GPIIIa rs2317676 may confer a higher risk for END. It was very important to modify clopidogrel therapy for the patients carrying the high-risk interactive genotypes.

CLINICAL TRIAL REGISTRATION INFORMATION

The study described here is registered at http://www.chictr.org/ (unique Identifier: ChiCTR-OCH-14004724). The date of trial registration was May 30, 2014.

Effect of Chitosan oligosaccharides on ischemic symptom and gut microbiota disbalance in mice with hindlimb ischemia

This study was designed to explore the effect of Chitosan oligosaccharides (COS) on mouse hindlimb ischemia by femoral artery ligation. Here, we demonstrated that COS treatment statistically promoted the blood perfusion and neovascularization in ischemic hindlimb of mice, accompanied by the suppression of inflammation and oxidative stress. By 16S rDNA gene sequencing, the disbalanced gut microbiota was observed in ischemic mice, while COS treatment, at least in part, restored the abundance changes of some intestinal bacteria at either phylum or genus levels. Based on metabolomics analysis on mouse plasma by UPLC-QTOF-MS, we screened 20 metabolites with the largest responses to ischemia, several of which were markedly reversed by COS. By Spearman's correlation analysis, the changed metabolites might act as a bridge between improved intestinal bacterial structure and alleviated hindlimb ischemia of mice treated by COS. Our studies point towards a potential role of COS in treatment of peripheral ischemia diseases.

Increasing trimethylamine N-oxide levels as a predictor of early neurological deterioration in patients with acute ischemic stroke

Background and aims: Trimethylamine N-oxide (TMAO), a pro-atherosclerotic intestinal microbiota metabolite, has mechanistic links to atherosclerosis development and cardiovascular diseases. In this study, we aimed to investigate whether serum TMAO levels could predict early neurological deterioration (END) after acute ischemic stroke.Methods: We prospectively recruited patients with first-ever ischemic stroke and hospitalized within 24 h of symptoms onset during Mar 2018 to Mar 2019. Plasma TMAO levels were quantified using stable isotope dilution high-performance liquid chromatography with tandem mass spectrometry after admission. END was defined as an increase in the total National Institutes of Health Stroke Scale by 2 or more points within 3 days.Results: Of the 362 patients included, END was diagnosed in 97 subjects (26.8%). The median TMAO concentrations were 4.8 μmol/L, with tertile levels as follows: first tertile (<3.9 μmol/L), second tertile (3.9-5.6 μmol/L), and third tertile (>5.6 μmol/L). Patients with END showed higher levels of TMAO (median 5.0 vs. 4.5 μmol/L, P = 0.005) at admission. In univariate logistic analysis, elevated plasma levels of TMAO [odd ratios for highest tertile vs. lowest tertile, 2.14; 95% confidence interval, 1.19-3.82] was a significant predictor of END in patients with ischemic stroke. This association remained significant after controlling for confounders in multivariate logistic analysis. Multiple-adjusted spline regression model further confirmed the dose-response relationship between TMAO levels and END (P < 0.001 for linearity).Conclusions: Our study indicated that increasing TMAO levels at admission might be associated with END after acute ischemic stroke.

Prevalence of stroke and stroke related risk factors: a population based cross sectional survey in southwestern China

Background

Stroke and its risk factors epidemiological survey can help identify individuals at higher risk and therefore promote stroke prevention strategies. The aim of this study was to estimate the current prevalence of stroke and high risk stroke population, and evaluate stroke associated risk factors in southwestern China.

Methods

This was a multi-center, cross sectional survey in southwestern China from May 2015 to September 2015. The eight communities were selected at random, and 17,413 residents aged ≥40 years volunteered to participate in this survey. Data were collected through face-to-face survey using a structured questionnaire. Five hundred twenty-one participants with incomplete questionnaires on stroke history or risk factors records were excluded.

Results

A total of 16,892 people included in analysis. The overall prevalence of stroke was 3.1% (95% CI 2.6–3.9%), 17.1% of participants were the high risk stroke population. After full adjustments, hypertension, diabetes, dyslipidemia, overweight, lack of exercise and family history of stroke were significantly associated with overall stroke and ischemic stroke. The largest contributor was hypertension (population-attributable risk 23.6%), followed by dyslipidemia, physical inactivity, family history of stroke, diabetes, and overweight. However, only hypertension (OR = 3.66, 95% CI 1.82–8.23) was significantly associated with hemorrhagic stroke.

Conclusions

The prevalence of stroke and high risk stroke population was high among adults aged ≥40 years in southwestern China. Hypertension, dyslipidemia and lack of exercise were stronger contributors for stroke, these findings suggest that individual-level and population-level interventions for these leading risk factors are necessary to prevent stroke.

Oxidative pathways of arachidonic acid as targets for regulation of platelet activation

Platelet activation plays an important role in acute and chronic cardiovascular disease states. Multiple pathways contribute to platelet activation including those dependent upon arachidonic acid. Arachidonic acid is released from the platelet membrane by phospholipase A2 action and is then metabolized in the cytosol by specific arachidonic acid oxidation enzymes including prostaglandin H synthase, 12-lipoxygenase, and cytochrome P450 to produce pro- and anti-inflammatory eicosanoids. This review aims to analyze the role of arachidonic acid oxidation on platelet activation, the enzymes that use it as a substrate associated as novel therapeutics target for antiplatelet drugs.

Conflicting Roles of 20-HETE in Hypertension and Stroke

Hypertension is the most common modifiable risk factor for stroke, and understanding the underlying mechanisms of hypertension and hypertension-related stroke is crucial. 20-hydroxy-5, 8, 11, 14-eicosatetraenoic acid (20-HETE), which plays an important role in vasoconstriction, autoregulation, endothelial dysfunction, angiogenesis, inflammation, and blood-brain barrier integrity, has been linked to hypertension and stroke. 20-HETE can promote hypertension by potentiating the vascular response to vasoconstrictors; it also can reduce blood pressure by inhibition of sodium transport in the kidney. The production of 20-HETE is elevated after the onset of both ischemic and hemorrhagic strokes; on the other hand, subjects with genetic variants in CYP4F2 and CYP4A11 that reduce 20-HETE production are more susceptible to stroke. This review summarizes recent genetic variants in CYP4F2, and CYP4A11 influencing 20-HETE production and discusses the role of 20-HETE in hypertension and the susceptibility to the onset, progression, and prognosis of ischemic and hemorrhagic strokes.

20-HETE synthesis inhibition promotes cerebral protection after intracerebral hemorrhage without inhibiting angiogenesis

20-HETE, an arachidonic acid metabolite synthesized by cytochrome P450 4A, plays an important role in acute brain damage from ischemic stroke or subarachnoid hemorrhage. We tested the hypothesis that 20-HETE inhibition has a protective effect after intracerebral hemorrhage (ICH) and then investigated its effect on angiogenesis. We exposed hippocampal slice cultures to hemoglobin and induced ICH in mouse brains by intrastriatal collagenase injection to investigate the protective effect of 20-HETE synthesis inhibitor N-hydroxy-N'-(4-n-butyl-2-methylphenyl)-formamidine (HET0016). Hemoglobin-induced neuronal death was assessed by propidium iodide after 18 h in vitro. Lesion volume, neurologic deficits, cell death, reactive oxygen species (ROS), neuroinflammation, and angiogenesis were evaluated at different time points after ICH. In cultured mouse hippocampal slices, HET0016 attenuated hemoglobin-induced neuronal death and decreased levels of proinflammatory cytokines and ROS. In vivo, HET0016 reduced brain lesion volume and neurologic deficits, and decreased neuronal death, ROS production, gelatinolytic activity, and the inflammatory response at three days after ICH. However, HET0016 did not inhibit angiogenesis, as levels of CD31, VEGF, and VEGFR2 were unchanged on day 28. We conclude that 20-HETE is involved in ICH-induced brain damage. Inhibition of 20-HETE synthesis may provide a viable means to mitigate ICH injury without inhibition of angiogenesis.

Matrix metalloproteinase-9 gene polymorphisms are associated with ischemic stroke severity and early neurologic deterioration in patients with atrial fibrillation

OBJECTIVES

The mechanisms of ischemic stroke severity and early neurologic deterioration (END) are not fully understood. The aim of the present study was to investigate the association of six variants in MMP-9 gene with ischemic stroke severity and the risk for END in ischemic stroke (IS) patients with atrial fibrillation (AF).

METHODS

This was a multi-center, prospective, observational study of 615 acute IS patients with AF admitted to six participating hospitals between June 2016 and October 2017. Ischemic stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) score on admission. END was defined as an increase of four or more points in NIHSS within 10 days of admission. Six variants of MMP-9 gene were examined using mass spectrometry.

RESULTS

Among the 615 enrolled patients, 112 (18.2%) patients presented with moderate or severe stroke (NIHSS score ≥16), and 108 (17.6%) patients suffered from END within 10 days of admission. Multiple logistic analysis showed that prestroke antiplatelet therapy, prestroke anticoagulant therapy, rs3918242 CT/TT, and rs3787268 AG/GG were independent predictors for stroke severity. Cox proportional hazard regression revealed that diabetes mellitus, prestroke antiplatelet therapy, prestroke anticoagulant therapy, rs1056628 AC/CC, and rs3918242 CT/TT were independently associated with the risk of END.

CONCLUSIONS

The incidence of moderate or severe stroke and END was very common in acute IS patients with AF. MMP-9 polymorphisms were independently associated with severe stroke and higher risk of END, and prestroke antithrombotic treatment was associated with less severe stroke and lower risk of END in patients with AF.

Variants in matrix metalloproteinase-9 gene are associated with hemorrhagic transformation in acute ischemic stroke patients with atherothrombosis, small artery disease, and cardioembolic stroke

OBJECTIVE

The potential effect of matrix metalloproteinase-9 (MMP-9) variants and these variants interactions on hemorrhagic transformation (HT) risk after ischemic stroke (IS) remain unclear. The aims of present study were to investigate the associations of six variants in MMP-9 with HT, and these variants interactions whether related to increased HT risk.

METHOD

A total of 705 patients with IS who were admitted to the participating hospitals within 48 hr of symptom onset were consecutively enrolled between March 2014 and December 2016. HT was confirmed by brain computed tomography (CT) scan during 14 days from stroke onset. Six variants of MMP-9 gene were measured by mass spectrometry. Interactions of gene variant-gene variant were assessed through generalized multifactor dimensionality reduction method (GMDR).

RESULTS

HT occurred in 104 (14.8%) patients. There were no differences in genotypes for the six variants between patients with and without HT using univariate analysis (all p > 0.05). GMDR analysis revealed that there was a synergistic effect of gene variant-gene variant interactions between rs3918242 and rs3787268 in MMP-9 gene. Cox regression analysis showed that high-risk interactions of rs3918242 and rs3787268 were associated with increased risk of HT after adjusting for covariates (hazard ratio: 2.08; 95% confidence interval: 1.34-7.85; p = 0.016).

CONCLUSION

Incidence of HT is common in acute IS in Chinese population. The mechanisms leading to HT are most likely multifactorial. Two-loci interactions of rs3918242 and rs3787268 in MMP-9 gene may confer a higher risk for HT.

Prestroke Aspirin Use is Associated with Clinical Outcomes in Ischemic Stroke Patients with Atherothrombosis, Small Artery Disease, and Cardioembolic Stroke

Aim: To evaluate the effect of prestroke aspirin (PA) use on initial stroke severity, early neurologic deterioration (END), stroke recurrence, hemorrhagic transformation (HT), and functional outcome in patients with ischemic stroke (IS).

Methods: This was a prospective, observational, multicenter cohort study. The acute IS patients with atherothrombosis (AT), small artery disease (SAD), or cardioembolic (CE) stroke within 24 hours of symptom onset were identified. National Institutes of Health Stroke Scale (NIHSS) scores on admission, clinical outcomes (END, recurrent ischemic stroke [RIS], myocardial infarction [MI], death, and hemorrhagic episodes), and functional outcome (modified Rankin Scale [mRS] scores) at three months after admission were compared between PA users and nonusers.

Results: Among the 1,862 patients, 401 (21.5%) reported PA use. The PA users had a significantly lower initial NIHSS score than the non-PA users. The effect was evident in AT stroke, but not in other subtypes. PA use was independently associated with the decreased risk of END. PA use increased the risk of HT; however, it was only associated with increased risk for asymptomatic HT, not for symptomatic HT. PA use was associated with better functional outcomes (mRS scores ≤ 2 points) irrespective of stroke subtypes at three months after admission, despite the increased risk of HT.

Conclusions: PA use may reduce initial stroke severity in AT stroke and the risk of END, and can improve functional outcome at three months irrespective of stroke subtypes.

Preceding Antithrombotic Treatment is Associated With Acute Ischemic Stroke Severity and Functional Outcome at 90 Days Among Patients With Atrial Fibrillation

BACKGROUND

Antithrombotic therapies are known to prevent ischemic stroke (IS) for patients with atrial fibrillation (AF), but are often underused in clinical practice. The aim of present study was to investigate the prevalence of patients with acute IS with known history of AF who were not receiving antithrombotic treatment before stroke and to evaluate the association of preceding antithrombotic treatment with stroke severity and outcomes at 90 days after admission.

MATERIALS AND METHODS

This was a retrospective, multi-center, observational study of 748 patients with acute IS and known history of AF admitted to 6 participating hospitals between March 2016 and October 2017. The primary outcome was stroke severity at admission as assessed using National Institutes of Health Stroke Scale (NIHSS) score. The secondary outcome was functional outcome at 90 days after admission as measured by modified Rankin Scale (mRS) score.

RESULTS

A total of 748 patients, 54 (7.2%) were receiving therapeutic warfarin (international normalized ratio [INR] ≥ 2) and 100 (13.4%) had subtherapeutic warfarin anticoagulation (INR < 2), 340 (45.5%) were receiving antiplatelet treatment, and 254 (34.0%) were not receiving any antithrombotic treatment prior to stroke. Compared with no antithrombotic treatment, therapeutic warfarin (OR: 0.64; 95% CI: 0.52-0.82; P = .022), and antiplatelet therapy only (OR: 0.89; 95% CI: 0.76-0.96; P = .041) were associated with lower odds ratio of moderate or severe stroke (NIHSS ≥ 16). Patients receiving preceding therapeutic warfarin (OR: 1.32; 95% CI: 1.22-3.57; P = .025), antiplatelet therapy only (OR: 1.13; 95% CI: 1.07-2.59; P = .043), and subtherapeutic warfarin with INR 1.5 to 1.99 (OR: 1.15; 95% CI: 1.10-2.66; P = .042) had higher odds ratio of better functional outcome (mRS ≤ 2) at 90 days.

CONCLUSIONS

Among patients with AF who had experienced an acute IS, inadequate therapeutic warfarin preceding the stroke was very prevalent in China. Therapeutic warfarin was associated with less severe stroke and better functional outcome at 90 days.

An overview of the biologic effects of omega-6 oxylipins in humans

Oxylipins are lipid mediators produced from polyunsaturated fatty acid (PUFA) metabolism, and are thought to be a molecular explanation for the diverse biological effects of PUFAs. Like PUFAs, oxylipins are distinguished by their omega-6 (n6) or omega-3 (n3) chemistry. We review the use of n6 oxylipins as biomarkers of disease and their use in diagnosis and risk assessment. We show cases where oxylipins derived from linoleate (LA) or arachidonate (AA) produced by the activities of lipoxygenase, cyclooxygenase, epoxygenase, ω/ω-1 hydroxylase, and autooxidation are useful as biomarkers or risk markers. HODEs, KODEs, EpOMEs, DiHOMEs, and other metabolites of LA as well as prostanoids, HETEs, KETEs, EpETrEs, and DiHETrEs, and other metabolites of AA were useful for understanding the different signaling environments in conditions from traumatic brain injury, to major coronary events, dyslipidemia, sepsis, and more. We next evaluate interventions that alter the concentrations of n6 oxylipins in plasma. We note the utility and response of each plasma fraction, and the generally increasing utility from the non-esterified, to the esterified, to the lipoprotein fractions. Finally, we review the effects which are specifically related to n6 oxylipins and most likely to be beneficial. Both n6 and n3 oxylipins work together in an exceedingly complex matrix to produce physiological effects. This overview should provide future investigators with important perspectives for the emerging utility of n6 oxylipins as products of n6 PUFAs in human health.

The contribution of TRPV1 channel to 20-HETE-Aggravated ischemic neuronal injury

20-Hydroxyeicosatetraenoic acid (20-HETE), a cytochrome P450 (CYP) 4A/4F-derived metabolite of arachidonic acid, directly contributes to ischemic neuronal injury. However, little is known about mediators of 20-HETE neurotoxicity after ischemia. Here, we focus on the role of transient receptor potential cation channel subfamily V member 1 (TRPV1) in 20-HETE-induced neurotoxicity. Our results showed that TRPV1 and CYP4A immunoreactivity were colocalized in neurons. TRPV1 inhibition attenuated 20-HETE mimetic 20-5,14-HEDGE-induced reactive oxygen species (ROS) production and neuronal injury in cultured neurons and protected ischemic neurons in vitro and in vivo. TRPV1 inhibition in combination with 20-HETE synthesis inhibitor HET0016 did not produce additional protective effects. Furthermore, TRPV1 genetic inhibition and NADPH oxidase inhibitor gp91ds-dat each attenuated ROS production to a similar extent. However, combined treatment did not achieve additional reduction. Therefore, we conclude that TRPV1 channels are involved in 20-HETE's ROS generation and neurotoxicity after ischemia.

Detrimental Effects of Testosterone Addition to Estrogen Therapy Involve Cytochrome P-450-Induced 20-HETE Synthesis in Aorta of Ovariectomized Spontaneously Hypertensive Rat (SHR), a Model of Postmenopausal Hypertension

Postmenopausal period has been associated to different symptoms such as hot flashes, vulvovaginal atrophy, hypoactive sexual desire disorder (HSDD) and others. Clinical studies have described postmenopausal women presenting HSDD can benefit from the association of testosterone to conventional hormonal therapy. Testosterone has been linked to development of cardiovascular diseases including hypertension and it also increases cytochrome P-450-induced 20-HETE synthesis which in turn results in vascular dysfunction. However, the effect of testosterone plus estrogen in the cardiovascular system is still very poorly studied. The aim of the present study is to evaluate the role of cytochrome P-450 pathway in a postmenopausal hypertensive female treated with testosterone plus estrogen. For that, hypertensive ovariectomized rats (OVX-SHR) were used as a model of postmenopausal hypertension and four groups were created: SHAM-operated (SHAM), ovariectomized SHR (OVX), OVX treated for 15 days with conjugated equine estrogens [(CEE) 9.6 μg/Kg/day/po] or CEE associated to testosterone [(CEE+T) 2.85 mg/kg/weekly/im]. Phenylephrine-induced contraction and generation of reactive oxygen species (ROS) were markedly increased in aortic rings from OVX-SHR compared to SHAM rats which were restored by CEE treatment. On the other hand, CEE+T abolished vascular effects by CEE and augmented both systolic and diastolic blood pressure of SHR. Treatment of aortic rings with the CYP/20-HETE synthesis inhibitor HET0016 (1 μM) reduced phenylephrine hyperreactivity and the augmented ROS generation in the CEE+T group. These results are paralleled by the increased CYP4F3 protein expression and activity in aortas of CEE+T. In conclusion, we showed that association of testosterone to estrogen therapy produces detrimental effects in cardiovascular system of ovariectomized hypertensive females via CYP4F3/20-HETE pathway. Therefore, our findings support the standpoint that the CYP/20-HETE pathway is an important therapeutic target for the prevention of cardiovascular disease in menopausal women in the presence of high levels of testosterone.

Changes in the hippocampal and peripheral phospholipid profiles are associated with neurodegeneration hallmarks in a long-term global cerebral ischemia model: Attenuation by Linalool

Phospholipid alterations in the brain are associated with progressive neurodegeneration and cognitive impairment after acute and chronic injuries. Various types of treatments have been evaluated for their abilities to block the progression of the impairment, but effective treatments targeting long-term post-stroke alterations are not available. In this study, we analyzed changes in the central and peripheral phospholipid profiles in ischemic rats and determined whether a protective monoterpene, Linalool, could modify them. We used an in vitro model of glutamate (125 μM) excitotoxicity and an in vivo global ischemia model in Wistar rats. Linalool (0.1 μM) protected neurons and astrocytes by reducing LDH release and restoring ATP levels. Linalool was administered orally at a dose of 25 mg/kg every 24 h for a month, behavioral tests were performed, and a lipidomic analysis was conducted using mass spectrometry. Animals treated with Linalool displayed faster neurological recovery than untreated ischemic animals, accompanied by better motor and cognitive performances. These results were confirmed by the significant reduction in astrogliosis, microgliosis and COX-2 marker, involving a decrease of 24:0 free fatty acid in the hippocampus. The altered profiles of phospholipids composed of mono and polyunsaturated fatty acids (PC 36:1; 42:1 (24:0/18:1)/LPC 22:6)/LPE 22:6) in the ischemic hippocampus and the upregulation of PI 36:2 and other LCFA (long chain fatty acids) in the serum of ischemic rats were prevented by the monoterpene. Based on these data, alterations in the central and peripheral phospholipid profiles after long-term was attenuated by oral Linalool, promoting a phospholipid homeostasis, related to the recovery of brain function.

Response to clopidogrel is associated with early neurological deterioration after acute ischemic stroke

Purpose

The relationship between response to clopidogrel and early neurological deterioration (END) after acute ischemic stroke (IS) is not well defined. The aim of present study was to evaluate the associations of clopidogrel resistance (CR) with END, and stratified analyze the effectiveness of clopidogrel alone and clopidogrel plus aspirin for the prevention of END.

Results

A total of 375 patients, 144 patients were received clopidogrel alone, 231 patients took clopidogrel plus aspirin. CR occurred in 153 patients (40.8%). 95 (25.3%) patients developed END within the first 10 days. Platelet aggregation was higher on admission, and inhibition of platelet aggregation was significantly lower in patients with END than patients without END. Diabetes mellitus, CR, and clopidogrel plus aspirin were independently associated with END. Dual antiplatelet therapy with aspirin and clopidogrel can inhibit both arachidonic acid (AA)-induced and ADP-induced platelet aggregation

Methods

This was a prospective, two-center study. A total of 375 IS patients taking clopidogrel alone or clopidogrel plus aspirin were enrolled. Platelet aggregation was measured before and after the 7–10 day treatment. CR was assessed by adenosine diphosphate (ADP)-induced platelet aggregation. The primary endpoint was END within the 10 days after admission. The secondary endpoint was a composite of recurrent ischemic stroke, myocardial infarction, and death during the 10 days after admission.

Conclusions

CR and END are fairly common after acute IS. CR is associated with higher risk of END. Clopidogrel plus aspirin combination therapy provides greater inhibition of platelet aggregation, and may afford protection against END.

P450 Eicosanoids and Reactive Oxygen Species Interplay in Brain Injury and Neuroprotection

Significance: Eicosanoids are endogenous lipid mediators that play important roles in brain function and disease. Acute brain injury such as that which occurs in stroke and traumatic brain injury increases the formation of eicosanoids, which, in turn, exacerbate or diminish injury. In chronic neurodegenerative diseases such as Alzheimer's disease and vascular dementia (VD), eicosanoid synthetic and metabolizing enzymes are altered, disrupting the balance between neuroprotective and neurotoxic eicosanoids. Recent Advances: Human and experimental studies have established the opposing roles of hydroxy- and epoxyeicosanoids and their potential utility as diagnostic biomarkers and therapeutic targets in neural injury. Critical Issues: A gap in knowledge remains in understanding the cellular and molecular mechanisms underlying the neurovascular actions of specific eicosanoids, such as specific isomers of epoxyeicosatrienoic (EETs) and hydroxyeicosatetraenoic acids (HETEs). Future Directions: EETs and HETEs exert their actions on brain cells by targeting multiple mechanisms, which include surface G-protein coupled receptors. The identification of high-affinity receptors for EETs and HETEs and their cellular localization in the brain will be a breakthrough in our understanding of these eicosanoids as mediators of cell-cell communications and contributors to brain development, function, and disease. Antioxid. Redox Signal. 28, 987-1007.

Interarm Blood Pressure Difference is Associated with Early Neurological Deterioration, Poor Short-Term Functional Outcome, and Mortality in Noncardioembolic Stroke Patients

Background and Purpose

Interarm differences in the systolic and diastolic blood pressures (IASBD and IADBD, respectively) are found in various populations, including stroke patients, but their significance for stroke outcomes has rarely been reported. We aimed to determine the associations of IASBD and IADBD with early neurological deterioration (END), functional outcome, and mortality.

Methods

This study included 1,008 consecutive noncardioembolic cerebral infarction patients who were admitted within 24 hours of onset and had automatic measurements of blood pressures in the bilateral arms. END was assessed within 72 hours of stroke onset according to predefined criteria. A poor functional outcome was defined as a score on the modified Rankin Scale ≥3 at 3 months after the index stroke. All-cause mortality was also investigated during a median follow-up of 24 months. The absolute difference of blood pressure measurements in both arms were used to define IASBD and IADBD.

Results

END occurred in 15.3% (155/1,008) of the patients. A multivariate analysis including sex, age, and variables for which the p value was <0.1 in a univariate analysis revealed that IASBD ≥10 mm Hg was significantly associated with END [odds ratio (OR)=1.75, 95% CI=1.02–3.01]. IADBD ≥10 mm Hg was also related to END (OR=3.11, 95% CI=1.61–5.99). Moreover, having both IASBD ≥10 mm Hg and IADBD ≥10 mm Hg was related to a poor functional outcome (OR=2.67, 95% CI=1.36–5.35) and mortality (hazard ratio=7.67, 95% CI=3.76–12.83) even after adjusting for END.

Conclusions

This study suggests that an interarm blood pressure difference of ≥10 mm Hg could be a useful indicator for the risks of END, poor functional outcome, and mortality.

Sex Differences in Regulation of Blood Pressure

Hypertension is one of the leading risk factors for cardiovascular disease, myocardial infarction, and stroke. There are gender differences in the prevalence of hypertension and in the mechanisms responsible for hypertension in humans. This review will discuss the mechanisms for regulation of blood pressure, sex differences that have been identified in animal studies, and the gender differences that have been identified in humans.

Platelet function-guided modification in antiplatelet therapy after acute ischemic stroke is associated with clinical outcomes in patients with aspirin nonresponse

PURPOSE

To investigate the association of clinical outcomes with platelet function-guided modification in antiplatelet therapy in patients with ischemic stroke.

RESULTS

Among 812 patients, 223 patients had aspirin nonresponse, 204 patients was modified in antiplatelet therapy after platelet function testing. Mean follow-up period was 4.8 ± 1.7 years (ranged from 1 to 6.4 years). The incidence rates of ischemic events, death, or bleeding events were not significantly different between the patients with and without antiplatelet therapy modification. However, in patients with aspirin nonresponse, antiplatelet therapy modification was associated with decreased ischemic events (hazard ratio, 0.67; 95% confidence interval [CI], 0.62-0.97; P = 0.01) and ischemic stroke (hazard ratio, 0.70; 95% CI, 0.63-0.98; P = 0.03) compared with no modification in antiplatelet therapy.

CONCLUSIONS

In patients with aspirin nonresponse, platelet function-guided modification in antiplatelet therapy after an ischemic stroke was associated with significantly lower rate of ischemic events. The platelet function testing may be useful to guide antiplatelet therapy modification.

METHODS

This is a retrospective, multicentre study. From August 2010 to December 2014, 812 patients with ischemic stroke underwent platelet function testing using platelet aggregation. Antiplatelet therapy modification was defined as any change in antiplatelet therapy after testing, including increasing aspirin dosage, adding an additional antiplatelet agent to aspirin, or switching to a more potent antiplatelet agent. The primary outcome was ischemic events. Secondary outcomes included death and bleeding events. Clinical outcomes were compared between patients with and without antiplatelet therapy modification using univariate and propensity score-adjusted analyses.

Epoxyeicosatrienoic Acids are Mediated by EPHX2 Variants and may be a Predictor of Early Neurological Deterioration in Acute Minor Ischemic Stroke

Aim: To investigatethe association of plasma epoxyeicosatrienoic acids (EETs) with early neurologic deterioration (END), and whether EETs are mediated by EPHX2 variants in patients with minor ischemic stroke (MIS).

Method: This was a prospective, multi-center observational study in patients with acute MIS in the Chinese population.Plasma EETs levels were measured on admission. Single nucleotide polymorphisms (SNPs) of EPHX2rs751141 were genotyped using mass spectrometry. The primary outcome was END within 10 days after admission. END was defined as an increase in NIHSS of 2 or more points. The degree of disability was assessed using the modified Rankin Scale (mRS) at 3 months after admission.

Results: A total of 322 patients were enrolled, of which 85 patients (26.4%) experienced END. The mean EETs level was 64.1 ± 7.5 nmol/L. EETs levels were significantly lower in patients with END compared to patients without END. Frequency of EPHX2 rs751141 GG was higher in patients with END than in patients without END, and EPHX2 rs751141 GG genotype was associated with lower EETs levels. Low level (< 64.4 nmol/L) of EETs was an independent predictor of END (first and second quartiles) in multivariate analyses. END was associated with a higher risk of poor outcome (mRS scores 3–6) at 3 months.

Conclusion: END is fairly common and associated with poor outcomes in acute MIS. EPHX2 variants may mediate EETs levels, and low levels of EETs may be a predictor for END in acute MIS.