Vitamin B6 prevents Isocarbophos-induced posterior cerebral artery injury in offspring rats through up-regulating S1P receptor expression.

We have previously reported that the long-term exposure of Isocarbophos, a kind of organophosphorus compounds, induces vascular dementia (VD) in rats. Studies have also shown that organophosphorus compounds have adverse effects on offsprings. Vitamin B6 is a coenzyme mainly involved in the regulation of metabolism and has been demonstrated to ameliorate VD. Sphingosine-1-phosphate (S1P), a biologically active lipid, plays a vital role in the cardiovascular system. However, whether S1P is involved in the therapeutic effects of Vitamin B6 on posterior cerebral artery injury has yet to be further answered. In the present study, we aimed to explore the potential influence of Vitamin B6 on Isocarbophos-induced posterior cerebral artery injury in offspring rats and the role of the S1P receptor in this process. We found that Vitamin B6 significantly improves the vasoconstriction function of the posterior cerebral artery in rats induced by Isocarbophos by the blood gas analysis and endothelium-dependent relaxation function assay. We further demonstrated that Vitamin B6 alleviates the Isocarbophos-induced elevation of ICAM-1, VCAM-1, IL-1, and IL-6 by using the enzyme-linked immunosorbent assay kits. By performing immunofluorescence and the western blot assay, we revealed that Vitamin B6 prevents the down-regulation of S1P in posterior cerebral artery injury. It is worth noting that Fingolimod, the S1P inhibitor, significantly inhibits the Vitamin B6-induced up-regulation of S1P in posterior cerebral artery injury. Collectively, our data indicate that Vitamin B6 may be a novel drug for the treatment of posterior cerebral artery injury and that S1P may be a drug target for its treatment.

Current treatment for childhood arterial ischaemic stroke.

Paediatric arterial ischaemic stroke is an important cause of neurological morbidity in children, with consequences including motor disorders, intellectual impairment, and epilepsy. The causes of paediatric arterial ischaemic stroke are unique compared with those associated with stroke in adulthood. The past decade has seen substantial advances in paediatric stroke research and clinical care, but many unanswered questions and controversies remain. Shortage of prospective evidence for the use of recanalisation therapies in patients with paediatric stroke has resulted in little standardisation of disease management. Substantial time delays in diagnosis and treatment continue to challenge best possible care. In this Review, we highlight on some of the most pressing and productive aspects of research in the treatment of arterial ischaemic stroke in children, including epidemiology and cause, rehabilitation, secondary stroke prevention, and treatment updates focusing on advances in hyperacute therapies such as intravenous thrombolysis, mechanical thrombectomy, and critical care. Finally, we provide a future perspective for improving outcomes and quality of life for affected children and their families.

Risk of acute arterial events associated with treatment of inflammatory bowel diseases: nationwide French cohort study.

OBJECTIVE: Patients with IBD are at increased risk of acute arterial events. Antitumour necrosis factor (TNF) agents and thiopurines may, via their anti-inflammatory properties, lower the risk of acute arterial events. The aim of this study was to assess the impact of thiopurines and anti-TNFs on the risk of acute arterial events in patients with IBD. DESIGN: Patients aged 18 years or older and affiliated to the French national health insurance with a diagnosis of IBD were followed up from 1 April 2010 until 31 December 2014. The risks of acute arterial events (including ischaemic heart disease, cerebrovascular disease and peripheral artery disease) were compared between thiopurines and anti-TNFs exposed and unexposed patients with marginal structural Cox proportional hazard models adjusting for baseline and time-varying demographics, medications, traditional cardiovascular risk factors, comorbidities and IBD disease activity. RESULTS: Among 177 827 patients with IBD (96 111 (54%) women, mean age at cohort entry 46.2 years (SD 16.3), 90 205 (50.7%) with Crohn's disease (CD)), 4145 incident acute arterial events occurred (incidence rates: 5.4 per 1000 person-years). Compared with unexposed patients, exposure to anti-TNFs (HR 0.79, 95% CI 0.66 to 0.95), but not to thiopurines (HR 0.93, 95% CI 0.82 to 1.05), was associated with a decreased risk of acute arterial events. The magnitude in risk reduction was highest in men with CD exposed to anti-TNFs (HR 0.54, 95% CI 0.40 to 0.72). CONCLUSION: Exposure to anti-TNFs is associated with a decreased risk of acute arterial events in patients with IBD, particularly in men with CD.

3-Aminobenzamide protects against cerebral artery injury and inflammation in rats with intracranial aneurysms.

This study aimed to investigate the treatment effects and molecular mechanism of 3-aminobenzamide (3-AB) on intracranial aneurysms (IA). The IA model was established in male Sprague-Dawley (SD) rats and sham group was set up without ligation. The rats were intraperitoneally injected with normal saline in sham and model control groups and 10 mg/kg, 20 mg/kg and 40 mg/kg 3-AB for low, middle and high 3-AB groups for 3 months, respectively. The rates in and blood pressures of caudal artery were measured and anterior cerebral artery and olfactory artery were stained with hematoxylin and eosin (HE) for morphology observation. Besides, the effects of 3-AB on inflammatory cells, macrophages, neutrophils and T cells, were evaluated using immunohistochemistry. Gene expressions of TNF-α, MMP-9, MMP-2, iNOS, TLR4, PARP-1 and p65 were measured using qRT-PCR and the protein levels of TLR4, PARP-1 and p-p65 were evaluated using western blotting. Blood pressures of rats in 3-AB treatment groups were decreased in a dose-dependent manner. The damage of cerebral artery wall was alleviated and the inflammatory cells (macrophages, neutrophils and T cells) were reduced to some extent in 3-AB high-dose groups. The gene expression of TNF-α, MMP-9, MMP-2, iNOS, TLR4, PARP-1 and p65, as well as the protein expression of TLR4, PARP-1 and p-p65 in 3-AB treatment groups were decreased in a dose-dependent manner (P < 0.01).3-AB exhibited therapeutic effects on IA through inhibiting the secretions of inflammatory cytokines and MMPs.

Clinical and haematological risk factors for cerebral macrovasculopathy in a sickle cell disease newborn cohort: a prospective study.

Children with sickle cell disease (SCD) have a significant vascular morbidity, especially cerebral macrovasculopathy (CV), detectable by transcranial Doppler. This study aimed to identify risk factors for CV using longitudinal biological and clinical data in a SCD newborn cohort followed at the Robert Debre Reference centre (n = 375 SS/Sß(0) ). Median follow-up was 6·8 years (2677 patient-years). Among the 59 children presenting with CV, seven had a stroke. Overall, the incidence of CV was 2·20/100 patient-years [95% confidence interval (95% CI): 1·64-2·76] and the incidence of stroke was 0·26/100 patient-years (95% CI: 0·07-0·46). The cumulative risk of CV by age 14 years was 26·0% (95% CI: 20·0-33·3%). Risk factors for CV were assessed by a Cox model encompassing linear multivariate modelling of longitudinal quantitative variables. Years per upper-airway obstruction [Hazard ratio (HR) = 1·47; 95% CI: 1·05-2·06] or bronchial obstruction (HR = 1·76; 95% CI: 1·49-2·08) and reticulocyte count (HR = 1·82 per 50 × 10(9) /l increase; 95% CI: 1·10-3·01) were independent risk factors whereas fetal haemoglobin level (HR = 0·68 per 5% increase; 95% CI: 0·48-0·96) was protective. Alpha-thalassaemia was not protective in multivariate analysis (ancillary analysis n = 209). Specific treatment for upper or lower-airway obstruction and indirect targeting of fetal haemoglobin and reticulocyte count by hydroxycarbamide could potentially reduce the risk of CV.

Rationale and Design of the PROSPECTIVE Trial: Probucol Trial for Secondary Prevention of Atherosclerotic Events in Patients with Prior Coronary Heart Disease.

BACKGROUND: Reduction of serum LDL-cholesterol by statins was shown to improve clinical outcomes in patients with coronary heart disease (CHD). Although intensive statin therapy significantly reduced cardiovascular risks, atherosclerotic cardiovascular events have not been completely prevented. Therefore, effective pharmacologic therapy is necessary to improve "residual risks" in combination with statins. Probucol has a potent antioxidative effect, inhibits the oxidation of LDL, and reduces xanthomas. Probucol Trial for Secondary Prevention of Atherosclerotic Events in Patients with Prior Coronary Heart Disease (PROSPECTIVE) is a multicenter, randomized, prospective study designed to test the hypothesis that the addition of probucol to other lipid-lowering drugs will prevent cerebro- and cardiovascular events in patients with prior coronary events and high LDL cholesterol levels. STUDY DESIGN: The study will recruit approximately 860 patients with a prior CHD and dyslipidemia with LDL-C level ≥140 mg/dl without any medication and those treated with any lipid-lowering drugs with LDL-C level ≥100 mg/dl. Lipid-lowering agents are continuously administered during the study period in control group, and probucol (500 mg/day, 250 mg twice daily) is added to lipid-lowering therapy in the test group. The efficacy and safety of probucol with regard to the prevention of cerebro- and cardiovascular events and the intima-media thickness of carotid arteries as a surrogate marker will be evaluated. SUMMARY: PROSPECTIVE will determine whether the addition of probucol to other lipid-lowering drugs improves cerebro- and cardiovascular outcomes in patients with prior coronary heart disease. Furthermore, the safety of a long-term treatment with probucol will be clarified.

Safety of anticoagulants in children with arterial ischemic stroke.

Pediatric arterial ischemic stroke (AIS) is increasingly diagnosed and carries significant risks of recurrence, morbidity, and mortality. Anticoagulant therapy (ACT) is commonly prescribed in childhood AIS. Hemorrhagic complication rates in pediatric stroke are unknown, and adult safety data are of limited applicability. We analyzed a prospectively enrolled cohort of children (aged 1 month-18 years) with acute AIS selected using standardized criteria for protocol-based ACT over 14-year period. We assessed ACT-associated intracranial hemorrhage (ICH), including frequency, clinical and radiologic characteristics, predictors, and outcome. Among 215 children with AIS, 123 received ACT within 7 days after diagnosis. During anticoagulation, 14 (11%) children developed new or increased ICH, all within 26 days from diagnosis. ICH was symptomatic in 5 (4%), asymptomatic in 9 (7%), and mild (European Cooperative Acute Stroke Study grades HI1 or HI2) in all but 1 child (ECASS PH-2). Long-term neurologic outcomes after ACT-associated ICH in survivors were abnormal in 73% (8/11). Comparably, 12 of 75 (16%) children treated without anticoagulation developed new or increased ICH on follow-up imaging (P = .3507). We conclude that ACT is relatively safe in children with AIS, with a 4% risk of symptomatic ICH. Based on the safety of ACT in our study, clinical trials of ACT in childhood AIS are warranted.

Failure to impact prevalence of arterial ischemic stroke in pediatric cardiac patients over three decades.

INTRODUCTION: Over the past three decades, significant advances in treatment have improved the mortality of children with cardiac disease. The effect of these advances on the prevalence of arterial ischemic stroke (AIS) is unknown. We describe AIS in children with cardiac disease in the modern era. DESIGN: The prospectively enrolled Intermountain Pediatric Stroke Database (including Utah, Wyoming, Idaho, and Nevada) was queried for all patients less than 18 years old with new-onset AIS between January 1, 2003 and August 31, 2009. Medical records of patients with AIS and cardiac disease were reviewed for cardiac diagnosis, age at AIS, anticoagulant therapy, diuretics, hematocrit, bolus fluids, and ongoing morbidity. Data were analyzed using chi-square test and a mixed-effects Poisson regression growth curve model. RESULTS: AIS incidence in our catchment area was 0.01% (10.7/100,000; N = 97). The incidence of AIS in patients with cardiac disease was higher compared with AIS in the total population (incidence 0.13% [132/100,000], odds ratio [OR] 16.1, 95% confidence interval [CI; 9.7--25.9], P < 0.001). Of the 97 patients with AIS, 24 had cardiac disease (25%). The most common cardiac diagnosis was single ventricle (SV; 8/24, 33%). The incidence of AIS in patients with SV cardiac disease was higher compared with those with other cardiac diagnoses (incidence 1.38% [1380/100,000], OR 15.3, 95% CI [5.7--38.2], P < 0.001). Modeling the prevalence estimates reported since 1978, the prevalence of cardiac disease in AIS patients has remained unchanged across time (prevalence increase per each additional year, 0.5%, 95% CI [--2.1%, 3.1%], P = 0.71). CONCLUSION: Children with cardiac disease (particularly those with SV) have increased risk for AIS. The prevalence is unchanged from reports over previous decades. AIS occurred in SV patients despite compliance with current anticoagulation recommendations. Future efforts should focus on best practices to prevent AIS in cardiac patients.

Overexpression of dimethylarginine dimethylaminohydrolase protects against cerebral vascular effects of hyperhomocysteinemia.

RATIONALE: Hyperhomocysteinemia is a cardiovascular risk factor that is associated with elevation of the nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA). OBJECTIVE: Using mice transgenic for overexpression of the ADMA-hydrolyzing enzyme dimethylarginine dimethylaminohydrolase-1 (DDAH1), we tested the hypothesis that overexpression of DDAH1 protects from adverse structural and functional changes in cerebral arterioles in hyperhomocysteinemia. METHODS AND RESULTS: Hyperhomocysteinemia was induced in DDAH1 transgenic (DDAH1 Tg) mice and wild-type littermates using a high methionine/low folate (HM/LF) diet. Plasma total homocysteine was elevated approximately 3-fold in both wild-type and DDAH1 Tg mice fed the HM/LF diet compared with the control diet (P<0.001). Plasma ADMA was approximately 40% lower in DDAH1 Tg mice compared with wild-type mice (P<0.001) irrespective of diet. Compared with the control diet, the HM/LF diet diminished endothelium-dependent dilation to 10 micromol/L acetylcholine in cerebral arterioles of both wild-type (12 + or - 2 versus 29 + or - 3%; P<0.001) and DDAH1 Tg (14 + or - 3 versus 28 + or - 2%; P<0.001) mice. Responses to 10 micromol/L papaverine, a direct smooth muscle dilator, were impaired with the HM/LF diet in wild-type mice (30 + or - 3 versus 45 + or - 5%; P<0.05) but not DDAH1 Tg mice (45 + or - 7 versus 48 + or - 6%). DDAH1 Tg mice also were protected from hypertrophy of cerebral arterioles (P<0.05) but not from accelerated carotid artery thrombosis induced by the HM/LF diet. CONCLUSIONS: Overexpression of DDAH1 protects from hyperhomocysteinemia-induced alterations in cerebral arteriolar structure and vascular muscle function.

Gamma-Hydroxybutyrate (GHB), gamma-butyrolactone (GBL), and 1,4-butanediol (1,4-BD) reduce the volume of cerebral infarction in rodent transient middle cerebral artery occlusion.

gamma-Hydroxybutyric acid (GHB), an endogenous organic acid catabolite of gamma-aminobutyric acid (GABA), has been shown to have tissue-protective effects in various organs, including the brain. We examined the potential neuroprotective effect of GHB and its chemical precursors, gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD), in the rodent ischemic stroke model by intraluminal filament middle cerebral artery occlusion (MCAO). Adult male Sprague-Dawley rats underwent transient left-sided MCAO and received intraperitoneal treatment with 300 mg/kg of GHB, GBL, 1,4-BD, or control vehicle given at 30 min before, as well as 180 and 360 min after the onset of ischemia. Infarct volumes were determined 24 h after MCAO. In transient MCAO, the mean volume of infarction for control rats was 464.4 +/- 17.9 cu.mm versus 273.6 +/- 53.1, 233.3 +/- 44.7, and 275.4 +/- 39.9 cu.mm for rats treated with 1,4-BD (P < 0.05), GBL (P < 0.05), and GHB (P < 0.05), respectively. We conclude that GHB, GBL, and 1,4-BD protect against rat focal cerebral ischemia from transient MCAO.

Deglycosylated anti-amyloid-beta antibodies eliminate cognitive deficits and reduce parenchymal amyloid with minimal vascular consequences in aged amyloid precursor protein transgenic mice.

Systemic administration of anti-amyloid-beta (Abeta) antibodies results in reduced parenchymal amyloid but increased vascular amyloid and microhemorrhage in amyloid precursor protein (APP) transgenic mice. Here, we evaluate the effects of reducing effector interactions of the antibody via deglycosylation. Mice aged 20 months were treated weekly for 4 months and tested behaviorally before they were killed. APP transgenic mice receiving either anti-Abeta (2H6) or deglycosylated anti-Abeta (de-2H6) showed significant improvement in radial arm water maze performance compared with mice receiving a control antibody. Both groups receiving anti-Abeta antibodies showed significant reductions in total Abeta immunochemistry and Congo red. Significantly fewer vascular amyloid deposits and microhemorrhages were observed in mice administered the de-2H6 antibody compared with those receiving unmodified 2H6 antibody. Deglycosylated anti-Abeta antibodies may be preferable to unmodified IgG because they retain the cognition-enhancing and amyloid-reducing properties of anti-Abeta immunotherapy, while greatly attenuating the increased vascular amyloid deposition and microhemorrhage observed with unmodified IgG.

Pretreatment with the free radical scavenger edaravone prevents cerebral hyperperfusion after carotid endarterectomy.

OBJECTIVE: Cerebral hyperperfusion syndrome after carotid endarterectomy (CEA) is a rare but potentially devastating complication. The purpose of the present study, which was not a randomized controlled trial but a case cohort study with historical control, was to determine whether pretreatment with a novel free radical scavenger, edaravone, could prevent occurrence of cerebral hyperperfusion after CEA. METHODS: Fifty patients with ipsilateral internal carotid artery stenosis (>/=70%) underwent CEA with administration of edaravone before internal carotid artery clamping. Preoperative cerebral blood flow and cerebrovascular reactivity (CVR) to acetazolamide were assessed with single-photon emission computed tomography (SPECT). Cerebral blood flow also was measured immediately after CEA and on the 3rd postoperative day. RESULTS: Cerebral hyperperfusion (cerebral blood flow increase >/=100% compared with preoperative values) was revealed by SPECT performed immediately after CEA in only one patient (2%), who also exhibited reduced preoperative CVR. The incidence of post-CEA hyperperfusion as revealed by SPECT in the control group (51 CEA patients without administration of edaravone) was significantly higher (16%) (P = 0.0310, control versus treatment group). In addition, in a subgroup of patients with reduced preoperative CVR, the incidence of post-CEA hyperperfusion as revealed by SPECT in the edaravone group (7%) was significantly lower than that in the control group (67%) (P = 0.0029). Logistic regression analysis demonstrated that reduced preoperative CVR and absence of pretreatment with edaravone were significant independent predictors of post-CEA hyperperfusion as revealed by SPECT. CONCLUSION: Pretreatment with edaravone can prevent occurrence of cerebral hyperperfusion after CEA.

Effect of combination of a tissue-type plasminogen activator and an endothelin receptor antagonist, FR139317, in the rat cerebral infarction model.

We were interested to investigate if a combination of a modified tissue-type plasminogen activator, SUN9216, which is constructed by modifying a single amino acid (Asn117-Gln117) to yield a tissue-type plasminogen activator lacking finger and growth factor domains with a long half-life in blood, and an endothelin receptor antagonist, FR139317, (R)2-[(R)-2-[(S)-2[[1-(hexahydro-1H-azepinyl)]carbonyl]amino-4- methyl-pentanoyl]amino-3-[3-(1-methyl-1H-indolyl)]propionyl)amino-3- (2-pyridyl)propionic acid, has greater thrombolytic efficacy than a thrombolytic agent alone in reducing the size of cerebral infarction. The thrombotic occlusion of the rat middle cerebral artery was induced by a photochemical reaction between rose bengal and green light, which causes endothelial injury followed by platelet adhesion and formation of a platelet-rich thrombus. SUN9216 (1 mg/kg) was injected intravenously 30 min after the middle cerebral artery occlusion and the time for reopening of the middle cerebral artery by SUN9216 was monitored for a 60-min period under an operating microscope. In the rats in which thrombolysis was achieved with SUN9216, the size of the cerebral infarction was significantly (P < 0.05) reduced as compared with that in the rats treated with saline and was comparable to the reduction produced by the combination doses. It is concluded that, under the present experimental conditions, endothelin may not be involved in the impaired local cerebral blood flow after thrombolysis.

AT-877, a Ca2+ antagonist, fails to reduce infarct size following rat middle-cerebral artery occlusion.

We investigated the effects of AT-877, a Ca2+ antagonist, on rat middle-cerebral artery occlusion. All rats had 6-h ischemia, and treated animals received either 3 or 10 mg/kg AT-877 s.c. just after the occlusion. Control animals received an equal volume of the vehicle. Prior to sacrifice, significant changes in the decrease of blood pressure and the increase of plasma glucose were observed in the treated rats. Although the infarct size tended to decrease, this decrease was not significant. Only when the blood pressure- or plasma glucose-matched subgroups were compared, the infarct volume decreased significantly in the drug-treated animals. Thus, AT-877 failed to reduce ischemic brain damage unless the blood pressure or plasma glucose were controlled.

[Thoughts about brain protection in carotid surgery]. / Réflexions à propos de la protection cérébrale dans la chirurgie carotidienne.

Brain protective measures and monitoring devices in carotid surgery tend towards absolute prevention of strokes without totally achieving this objective. When a post-operative stroke occurs, the question is: is it a brain protection failure, a technical fault or an ill-advised indication? However, apart from massive stroke, other significant disorders may occur especially affecting higher functions. We studied a series of 126 patients with a mean age of 68.4 years who underwent 140 carotid repairs. The average clamping time was 21.8 min. Brain protection always consisted of: general anesthesia and heparinization, hyperoxygenation, light hypercapnia without shunting or monitoring. Two deaths and one hemiplegia (2.1%) were due to an incorrect indication or technical error. Three resolving neurological events were related to clamping intolerance (2.1%). What appears to be responsible, in case of stroke, is not so much clamping but technical errors. We also observed disturbances of higher functions in 25 patients (17.8%). A study using psychometric tests performed preoperatively and at a convenient time from the operation is proposed in order to demonstrate carotid clamping effects on higher functions.