Targeting reactive nitrogen species: a promising therapeutic strategy for cerebral ischemia-reperfusion injury.

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Chen, Xing-miao; Chen, Han-sen; Xu, Ming-jing; Shen, Jian-gang

2013-01-01

Ischemic stroke accounts for nearly 80% of stroke cases. Recanalization with thrombolysis is a currently crucial therapeutic strategy for re-building blood supply, but the thrombolytic therapy often companies with cerebral ischemia-reperfusion injury, which are mediated by free radicals. As an important component of free radicals, reactive nitrogen species (RNS), including nitric oxide (NO) and peroxynitrite (ONOO(-)), play important roles in the process of cerebral ischemia-reperfusion injury. Ischemia-reperfusion results in the production of nitric oxide (NO) and peroxynitrite (ONOO(-)) in ischemic brain, which trigger numerous molecular cascades and lead to disruption of the blood brain barrier and exacerbate brain damage. There are few therapeutic strategies available for saving ischemic brains and preventing the subsequent brain damage. Recent evidence suggests that RNS could be a therapeutic target for the treatment of cerebral ischemia-reperfusion injury. Herein, we reviewed the recent progress regarding the roles of RNS in the process of cerebral ischemic-reperfusion injury and discussed the potentials of drug development that target NO and ONOO(-) to treat ischemic stroke. We conclude that modulation for RNS level could be an important therapeutic strategy for preventing cerebral ischemia-reperfusion injury.

Protective effect of zinc against ischemic neuronal injury in a middle cerebral artery occlusion model.

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Kitamura, Youji; Iida, Yasuhiko; Abe, Jun; Ueda, Masashi; Mifune, Masaki; Kasuya, Fumiyo; Ohta, Masayuki; Igarashi, Kazuo; Saito, Yutaka; Saji, Hideo

2006-02-01

In this study, we investigated the effect of vesicular zinc on ischemic neuronal injury. In cultured neurons, addition of a low concentration (under 100 microM) of zinc inhibited both glutamate-induced calcium influx and neuronal death. In contrast, a higher concentration (over 150 microM) of zinc decreased neuronal viability, although calcium influx was inhibited. These results indicate that zinc exhibits biphasic effects depending on its concentration. Furthermore, in cultured neurons, co-addition of glutamate and CaEDTA, which binds extra-cellular zinc, increased glutamate-induced calcium influx and aggravated the neurotoxicity of glutamate. In a rat transient middle cerebral artery occlusion (MCAO) model, the infarction volume, which is related to the neurotoxicity of glutamate, increased rapidly on the intracerebral ventricular injection of CaEDTA 30 min prior to occlusion. These results suggest that zinc released from synaptic vesicles may provide a protective effect against ischemic neuronal injury.

Ischemia preconditioning is neuroprotective in a rat cerebral ischemic injury model through autophagy activation and apoptosis inhibition

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Xia, D.Y.; Li, W.; Qian, H.R.; Yao, S.; Liu, J.G.; Qi, X.K.

2013-01-01

Sublethal ischemic preconditioning (IPC) is a powerful inducer of ischemic brain tolerance. However, its underlying mechanisms are still not well understood. In this study, we chose four different IPC paradigms, namely 5 min (5 min duration), 5×5 min (5 min duration, 2 episodes, 15-min interval), 5×5×5 min (5 min duration, 3 episodes, 15-min intervals), and 15 min (15 min duration), and demonstrated that three episodes of 5 min IPC activated autophagy to the greatest extent 24 h after IPC, as evidenced by Beclin expression and LC3-I/II conversion. Autophagic activation was mediated by the tuberous sclerosis type 1 (TSC1)-mTor signal pathway as IPC increased TSC1 but decreased mTor phosphorylation. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and hematoxylin and eosin staining confirmed that IPC protected against cerebral ischemic/reperfusion (I/R) injury. Critically, 3-methyladenine, an inhibitor of autophagy, abolished the neuroprotection of IPC and, by contrast, rapamycin, an autophagy inducer, potentiated it. Cleaved caspase-3 expression, neurological scores, and infarct volume in different groups further confirmed the protection of IPC against I/R injury. Taken together, our data indicate that autophagy activation might underlie the protection of IPC against ischemic injury by inhibiting apoptosis

Ischemia preconditioning is neuroprotective in a rat cerebral ischemic injury model through autophagy activation and apoptosis inhibition

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Xia, D.Y. [Department of Neurology, Navy General Hospital of PLA, Beijing (China); Li, W. [General Hospital of Shenyang Military Command, Department of Neurology, Shenyang, China, Department of Neurology, General Hospital of Shenyang Military Command, Shenyang (China); Qian, H.R.; Yao, S.; Liu, J.G.; Qi, X.K. [Department of Neurology, Navy General Hospital of PLA, Beijing (China)

2013-08-10

Sublethal ischemic preconditioning (IPC) is a powerful inducer of ischemic brain tolerance. However, its underlying mechanisms are still not well understood. In this study, we chose four different IPC paradigms, namely 5 min (5 min duration), 5×5 min (5 min duration, 2 episodes, 15-min interval), 5×5×5 min (5 min duration, 3 episodes, 15-min intervals), and 15 min (15 min duration), and demonstrated that three episodes of 5 min IPC activated autophagy to the greatest extent 24 h after IPC, as evidenced by Beclin expression and LC3-I/II conversion. Autophagic activation was mediated by the tuberous sclerosis type 1 (TSC1)-mTor signal pathway as IPC increased TSC1 but decreased mTor phosphorylation. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and hematoxylin and eosin staining confirmed that IPC protected against cerebral ischemic/reperfusion (I/R) injury. Critically, 3-methyladenine, an inhibitor of autophagy, abolished the neuroprotection of IPC and, by contrast, rapamycin, an autophagy inducer, potentiated it. Cleaved caspase-3 expression, neurological scores, and infarct volume in different groups further confirmed the protection of IPC against I/R injury. Taken together, our data indicate that autophagy activation might underlie the protection of IPC against ischemic injury by inhibiting apoptosis.

Baicalin attenuates focal cerebral ischemic reperfusion injury through inhibition of nuclear factor κB p65 activation

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Xue, Xia; Qu, Xian-Jun; Yang, Ying; Sheng, Xie-Huang; Cheng, Fang; Jiang, E-Nang; Wang, Jian-hua; Bu, Wen; Liu, Zhao-Ping

2010-01-01

Research highlights: → Permanent NF-κB p65 activation contributes to the infarction after ischemia-reperfusion injury in rats. → Baicalin can markedly inhibit the nuclear NF-κB p65 expression and m RNA levels after ischemia-reperfusion injury in rats. → Baicalin decreased the cerebral infarction area via inhibiting the activation of nuclear NF-κB p65. -- Abstract: Baicalin is a flavonoid compound purified from plant Scutellaria baicalensis Georgi. We aimed to evaluate the neuroprotective effects of baicalin against cerebral ischemic reperfusion injury. Male Wistar rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h followed by reperfusion for 24 h. Baicalin at doses of 50, 100 and 200 mg/kg was intravenously injected after ischemia onset. Twenty-four hours after reperfusion, the neurological deficit was scored and infarct volume was measured. Hematoxylin and eosin (HE) staining was performed to analyze the histopathological changes of cortex and hippocampus neurons. We examined the levels of NF-κB p65 in ischemic cortexes by Western blot analysis and RT-PCR assay. The results showed that the neurological deficit scores were significantly decreased from 2.0 ± 0.7 to 1.2 ± 0.4 and the volume of infarction was reduced by 25% after baicalin injection. Histopathological examination showed that the increase of neurons with pycnotic shape and condensed nuclear in cortex and hippocampus were not observed in baicalin treated animals. Further examination showed that NF-κB p65 in cortex was increased after ischemia reperfusion injury, indicating the molecular mechanism of ischemia reperfusion injury. The level of NF-κB p65 was decreased by 73% after baicalin treatment. These results suggest that baicalin might be useful as a potential neuroprotective agent in stroke therapy. The neuroprotective effects of baicalin may relate to inhibition of NF-κB p65.

Protection by the gross saponins of Tribulus terrestris against cerebral ischemic injury in rats involves the NF-κB pathway

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En-ping Jiang

2011-06-01

Full Text Available The aim of this study was to investigate whether the gross saponins of Tribulus terrestris (GSTT, a traditional Chinese herbal medicine, have neuroprotective effects on rats subjected to middle cerebral artery occlusion (MCAO, through nuclear factor-κB (NF-κB pathway and inflammatory mediators. Cerebral ischemia was produced by MCAO in either untreated (control or GSTT-pretreated rats, and the animals were examined for infarct volume, cerebral edema, neuro-behavioral abnormality and pathological changes. Meanwhile, the expression of NF-κB protein in brain tissue was analyzed on Western blots and the serum levels of TNF-α and IL-1 were determined by ELISA. The experimental results demonstrated that, compared with the control MCAO group, GSTT-pretreated MCAO group had significantly reduced infarct volume, brain edema and neuro-behavioral abnormality, and lesser degree of pathologic changes in the brain, as well as had lower levels of serum TNF-α and IL-1β, and higher levels of brain NF-κB (P<0.05. Furthermore, treatment with an NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC abolished the protective effects of GSTT against MCAO-induced cerebral ischemic injury. These results indicated that GSTT's ability to protect against cerebral ischemic injury was mediated through the NF-κB signaling pathway, and that GSTT may act through inhibition of the production of inflammatory mediators.

ischemic brain injury in neonatal rats

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Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, ... Methods: Forty-eight rats (P7-pups) were randomly assigned to one of four groups: ... Keywords: Hypoxic–ischemic brain injury, α-Lipoic acid, Cerebral infarct area, Edema, Antioxidants, .... Of the 48 rats initially used in the current study, 5.

Pre-Ischemic Treadmill Training for Prevention of Ischemic Brain Injury via Regulation of Glutamate and Its Transporter GLT-1

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Jingchun Guo

2012-07-01

Full Text Available Pre-ischemic treadmill training exerts cerebral protection in the prevention of cerebral ischemia by alleviating neurotoxicity induced by excessive glutamate release following ischemic stroke. However, the underlying mechanism of this process remains unclear. Cerebral ischemia-reperfusion injury was observed in a rat model after 2 weeks of pre-ischemic treadmill training. Cerebrospinal fluid was collected using the microdialysis sampling method, and the concentration of glutamate was determined every 40 min from the beginning of ischemia to 4 h after reperfusion with high-performance liquid chromatography (HPLC-fluorescence detection. At 3, 12, 24, and 48 h after ischemia, the expression of the glutamate transporter-1 (GLT-1 protein in brain tissues was determined by Western blot respectively. The effect of pre-ischemic treadmill training on glutamate concentration and GLT-1 expression after cerebral ischemia in rats along with changes in neurobehavioral score and cerebral infarct volume after 24 h ischemia yields critical information necessary to understand the protection mechanism exhibited by pre-ischemic treadmill training. The results demonstrated that pre-ischemic treadmill training up-regulates GLT-1 expression, decreases extracellular glutamate concentration, reduces cerebral infarct volume, and improves neurobehavioral score. Pre-ischemic treadmill training is likely to induce neuroprotection after cerebral ischemia by regulating GLT-1 expression, which results in re-uptake of excessive glutamate.

Cerebral Lactate Concentration in Neonatal Hypoxic-Ischemic Encephalopathy: In Relation to Time, Characteristic of Injury, and Serum Lactate Concentration

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Tai-Wei Wu

2018-05-01

Full Text Available BackgroundCerebral lactate concentration can remain detectable in neonatal hypoxic-ischemic encephalopathy (HIE after hemodynamic stability. The temporal resolution of regional cerebral lactate concentration in relation to the severity or area of injury is unclear. Furthermore, the interplay between serum and cerebral lactate in neonatal HIE has not been well defined. The study aims to describe cerebral lactate concentration in neonatal HIE in relation to time, injury, and serum lactate.Design/methodsFifty-two newborns with HIE undergoing therapeutic hypothermia (TH were enrolled. Magnetic resonance imaging and spectroscopy (MRI + MR spectroscopy were performed during and after TH at 54.6 ± 15.0 and 156 ± 57.6 h of life, respectively. Severity and predominant pattern of injury was scored radiographically. Single-voxel 1H MR spectra were acquired using short-echo (35 ms PRESS sequence localized to the basal ganglia (BG, thalamus (Thal, gray matter (GM, and white matter. Cerebral lactate concentration was quantified by LCModel software. Serum and cerebral lactate concentrations were plotted based on age at time of measurement. Multiple comparisons of regional cerebral lactate concentration based on severity and predominant pattern of injury were performed. Spearman’s Rho was computed to determine correlation between serum lactate and cerebral lactate concentration at the respective regions of interest.ResultsOverall, serum lactate concentration decreased over time. Cerebral lactate concentration remained low for less severe injury and decreased over time for more severe injury. Cerebral lactate remained detectable even after TH. During TH, there was a significant higher concentration of cerebral lactate at the areas of injury and also when injury was more severe. However, these differences were no longer observed after TH. There was a weak correlation between serum lactate and cerebral lactate concentration at the BG (rs�

A pathophysiological role of TRPV1 in ischemic injury after transient focal cerebral ischemia in mice

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Miyanohara, Jun [Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University (Japan); Shirakawa, Hisashi, E-mail: shirakaw@pharm.kyoto-u.ac.jp [Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University (Japan); Sanpei, Kazuaki [Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University (Japan); Nakagawa, Takayuki [Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University (Japan); Department of Clinical Pharmacology and Therapeutics, Kyoto University Hospital (Japan); Kaneko, Shuji [Department of Molecular Pharmacology, Graduate School of Pharmaceutical Sciences, Kyoto University (Japan)

2015-11-20

Transient receptor potential vanilloid 1 (TRPV1) is a non-selective cation channel with high Ca{sup 2+} permeability, which functions as a polymodal nociceptor activated by heat, protons and several vanilloids, including capsaicin and anandamide. Although TRPV1 channels are widely distributed in the mammalian brain, their pathophysiological roles in the brain remain to be elucidated. In this study, we investigated whether TRPV1 is involved in cerebral ischemic injury using a middle cerebral artery (MCA) occlusion model in wild-type (WT) and TRPV1-knockout (KO) mice. For transient ischemia, the left MCA of C57BL/6 mice was occluded for 60 min and reperfused at 1 and 2 days after ischemia. We found that neurological and motor deficits, and infarct volumes in TRPV1-KO mice were lower than those of WT mice. Consistent with these results, intracerebroventricular injection of a TRPV1 antagonist, capsazepine (20 nmol), 30 min before the onset of ischemia attenuated neurological and motor deficits and improved infarct size without influencing cerebral blood flow in the occluded MCA territory. The protective effect of capsazepine on ischemic brain damage was not observed in TRPV1-KO mice. WT and TRPV1-KO mice did not show any differences with respect to the increased number of Iba1-positive microglia/macrophages, GFAP-positive astrocytes, and Gr1-positive neutrophils at 1 and 2 days after cerebral ischemia. Taken together, we conclude that brain TRPV1 channels are activated by ischemic stroke and cause neurological and motor deficits and infarction after brain ischemia. - Highlights: • We investigated whether TRPV1 is involved in transient ischemic brain damage in mice. • Neurological deficits and infarct volumes were lower in TRPV1-KO mice than in WT mice. • Injection of a TRPV1 antagonist, capsazepine, attenuated neurological deficits and improved infarct size. • No differences in astrocytic or microglial activation were observed between WT and TRPV1-KO mice.

A pathophysiological role of TRPV1 in ischemic injury after transient focal cerebral ischemia in mice

International Nuclear Information System (INIS)

Miyanohara, Jun; Shirakawa, Hisashi; Sanpei, Kazuaki; Nakagawa, Takayuki; Kaneko, Shuji

2015-01-01

Transient receptor potential vanilloid 1 (TRPV1) is a non-selective cation channel with high Ca"2"+ permeability, which functions as a polymodal nociceptor activated by heat, protons and several vanilloids, including capsaicin and anandamide. Although TRPV1 channels are widely distributed in the mammalian brain, their pathophysiological roles in the brain remain to be elucidated. In this study, we investigated whether TRPV1 is involved in cerebral ischemic injury using a middle cerebral artery (MCA) occlusion model in wild-type (WT) and TRPV1-knockout (KO) mice. For transient ischemia, the left MCA of C57BL/6 mice was occluded for 60 min and reperfused at 1 and 2 days after ischemia. We found that neurological and motor deficits, and infarct volumes in TRPV1-KO mice were lower than those of WT mice. Consistent with these results, intracerebroventricular injection of a TRPV1 antagonist, capsazepine (20 nmol), 30 min before the onset of ischemia attenuated neurological and motor deficits and improved infarct size without influencing cerebral blood flow in the occluded MCA territory. The protective effect of capsazepine on ischemic brain damage was not observed in TRPV1-KO mice. WT and TRPV1-KO mice did not show any differences with respect to the increased number of Iba1-positive microglia/macrophages, GFAP-positive astrocytes, and Gr1-positive neutrophils at 1 and 2 days after cerebral ischemia. Taken together, we conclude that brain TRPV1 channels are activated by ischemic stroke and cause neurological and motor deficits and infarction after brain ischemia. - Highlights: • We investigated whether TRPV1 is involved in transient ischemic brain damage in mice. • Neurological deficits and infarct volumes were lower in TRPV1-KO mice than in WT mice. • Injection of a TRPV1 antagonist, capsazepine, attenuated neurological deficits and improved infarct size. • No differences in astrocytic or microglial activation were observed between WT and TRPV1-KO mice.

Ligustrazine monomer against cerebral ischemia-reperfusion injury

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Hai-jun Gao

2015-01-01

Full Text Available Ligustrazine (2,3,5,6-tetramethylpyrazine is a major active ingredient of the Szechwan lovage rhizome and is extensively used in treatment of ischemic cerebrovascular disease. The mechanism of action of ligustrazine use against ischemic cerebrovascular diseases remains unclear at present. This study summarizes its protective effect, the optimum time window of administration, and the most effective mode of administration for clinical treatment of cerebral ischemia/reperfusion injury. We examine the effects of ligustrazine on suppressing excitatory amino acid release, promoting migration, differentiation and proliferation of endogenous neural stem cells. We also looked at its effects on angiogenesis and how it inhibits thrombosis, the inflammatory response, and apoptosis after cerebral ischemia. We consider that ligustrazine gives noticeable protection from cerebral ischemia/reperfusion injury. The time window of ligustrazine administration is limited. The protective effect and time window of a series of derivative monomers of ligustrazine such as 2-[(1,1-dimethylethyloxidoimino]methyl]-3,5,6-trimethylpyrazine, CXC137 and CXC195 after cerebral ischemia were better than ligustrazine.

Actualities on molecular pathogenesis and repairing processes of cerebral damage in perinatal hypoxic-ischemic encephalopathy

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Praticò Andrea D

2010-09-01

Full Text Available Abstract Hypoxic-ischemic encephalopathy (HIE is the most important cause of cerebral damage and long-term neurological sequelae in the perinatal period both in term and preterm infant. Hypoxic-ischemic (H-I injuries develop in two phases: the ischemic phase, dominated by necrotic processes, and the reperfusion phase, dominated by apoptotic processes extending beyond ischemic areas. Due to selective ischemic vulnerability, cerebral damage affects gray matter in term newborns and white matter in preterm newborns with the typical neuropathological aspects of laminar cortical necrosis in the former and periventricular leukomalacia in the latter. This article summarises the principal physiopathological and biochemical processes leading to necrosis and/or apoptosis of neuronal and glial cells and reports recent insights into some endogenous and exogenous cellular and molecular mechanisms aimed at repairing H-I cerebral damage.

Neuroprotective Effect of the Ginsenoside Rg1 on Cerebral Ischemic Injury In Vivo and In Vitro Is Mediated by PPARγ-Regulated Antioxidative and Anti-Inflammatory Pathways

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Yang Li

2017-01-01

Full Text Available The ginsenoside Rg1 exerts a neuroprotective effect during cerebral ischemia/reperfusion injury. Rg1 has been previously reported to improve PPARγ expression and signaling, consequently enhancing its regulatory processes. Due to PPARγ’s role in the suppression of oxidative stress and inflammation, Rg1’s PPARγ-normalizing capacity may play a role in the observed neuroprotective action of Rg1 during ischemic brain injury. We utilized a middle cerebral artery ischemia/reperfusion injury model in rats in addition to an oxygen glucose deprivation model in cortical neurons to elucidate the mechanisms underlying the neuroprotective effects of Rg1. We found that Rg1 significantly increased PPARγ expression and reduced multiple indicators of oxidative stress and inflammation. Ultimately, Rg1 treatment improved neurological function and diminished brain edema, indicating that Rg1 may exert its neuroprotective action on cerebral ischemia/reperfusion injury through the activation of PPARγ signaling. In addition, the present findings suggested that Rg1 was a potent PPARγ agonist in that it upregulated PPARγ expression and was inhibited by GW9662, a selective PPARγ antagonist. These findings expand our previous understanding of the molecular basis of the therapeutic action of Rg1 in cerebral ischemic injury, laying the ground work for expanded study and clinical optimization of the compound.

Electrical stimulation of the vagus nerve protects against cerebral ischemic injury through an anti-infammatory mechanism

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Yao-xian Xiang

2015-01-01

Full Text Available Vagus nerve stimulation exerts protective effects against ischemic brain injury; however, the underlying mechanisms remain unclear. In this study, a rat model of focal cerebral ischemia was established using the occlusion method, and the right vagus nerve was given electrical stimulation (constant current of 0.5 mA; pulse width, 0.5 ms; frequency, 20 Hz; duration, 30 seconds; every 5 minutes for a total of 60 minutes 30 minutes, 12 hours, and 1, 2, 3, 7 and 14 days after surgery. Electrical stimulation of the vagus nerve substantially reduced infarct volume, improved neurological function, and decreased the expression levels of tumor necrosis factor-and interleukin- 6 in rats with focal cerebral ischemia. The experimental findings indicate that the neuroprotective effect of vagus nerve stimulation following cerebral ischemia may be associated with the inhibition of tumor necrosis factor- and interleukin-6 expression.

Perinatal Hypoxic-Ischemic brain injury; MR findings

International Nuclear Information System (INIS)

Park, Dong Woo; Seo, Chang Hye

1994-01-01

To characterize the MR findings of hypoxic-ischemic brain injury and to assess the value of the MR imaging. SE T1-, T2-weighted, and IR brain MR images of 44 infants and children with the past history of perinatal hypoxic insults were reviewed. Abnormal brain MR findings of 8 patients with birth history of prematurity and 36 patients with birth history of full-term/posterm including 7 with severe anoxic insult history, were compared in regard to the location and the character of the lesions. MRI demonstrated the followings; (1)abnormal signal intensity lesions of subcortical and/or deep cerebral white matter, cortex, and deep gray matter, (2)atrophy of the cerebral white matter, cortex and corpus callosum, with/without ventriculomegaly, and (3)delay in myelination. Periventricular and deep white matter lesions were demonstrated in the prematurity, the deep white matter lesions and/ or subcortical white matter lesions in the term/post-term, and deep gray matter lesions in the 7 patients with severe anoxic insults history. MR imaging was useful in the diagnosis of the hypoxic-ischemic brain injury, and the white and gray matter lesions were correlated with the time of the injury and the severity of hypoxic insult

Imaging of rat cerebral ischemia-reperfusion injury using99mTc-labeled duramycin

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Zhang Yuqing; Stevenson, Gail D.; Barber, Christy; Furenlid, Lars R.; Barrett, Harrison H.; Woolfenden, James M.; Zhao Ming; Liu Zhonglin

2013-01-01

Objectives: Prompt identification of necrosis and apoptosis in the infarct core and penumbra region is critical in acute stroke for delineating the underlying ischemic/reperfusion molecular pathologic events and defining therapeutic alternatives. The objective of this study was to investigate the capability of 99m Tc-labeled duramycin in detecting ischemia-reperfusion injury in rat brain after middle cerebral artery (MCA) occlusion. Methods: Ischemic cerebral injury was induced in ten rats by vascular insertion of a nylon suture in the left MCA for 3 hr followed by 21–24 hr reperfusion. After i.v. injection of 99m Tc-duramycin (1.0-3.5 mCi), dynamic cerebral images were acquired for 1 hr in six rats using a small-animal SPECT imager. Four other rats were imaged at 2 hr post-injection. Ex vivo images were obtained by autoradiography after sacrifice. Histologic analyses were performed to assess cerebral infarction and apoptosis. Results: SPECT images showed that 99m Tc-duramycin uptake in the left cerebral hemisphere was significantly higher than that in the right at 1 and 2 hr post-injection. The level of radioactive uptake in the ischemic brain varied based on ischemic severity. The average ratio of left cerebral hot-spot uptake to right hemisphere radioactivity, as determined by computerized ROI analysis, was 4.92 ± 0.79. Fractional washout at 1 hr was 38.2 ± 4.5% of peak activity for left cerebral hot-spot areas and 80.9 ± 2.0% for remote control areas (P 99m Tc-duramycin SPECT imaging may be useful for detecting and quantifying ongoing apoptotic neuronal cell loss induced by ischemia-reperfusion injury.

Sevoflurane postconditioning against cerebral ischemic neuronal injury is abolished in diet-induced obesity: role of brain mitochondrial KATP channels.

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Yang, Zecheng; Chen, Yunbo; Zhang, Yan; Jiang, Yi; Fang, Xuedong; Xu, Jingwei

2014-03-01

Obesity is associated with increased infarct volumes and adverse outcomes following ischemic stroke. However, its effect on anesthetic postconditioning‑induced neuroprotection has not been investigated. The present study examined the effect of sevoflurane postconditioning on focal ischemic brain injury in diet‑induced obesity. Sprague‑Dawley rats were fed a high‑fat diet (HF; 45% kcal as fat) for 12 weeks to develop obesity syndrome. Rats fed a low‑fat diet (LF; 10% kcal as fat) served as controls. The HF or LF‑fed rats were subjected to focal cerebral ischemia for 60 min, followed by 24 h of reperfusion. Postconditioning was performed by exposure to sevoflurane for 15 min immediately at the onset of reperfusion. The involvement of the mitochondrial KATP (mitoKATP) channel was analyzed by the administration of a selective inhibitor of 5‑hydroxydecanoate (5‑HD) prior to sevoflurane postconditioning or by administration of diazoxide (DZX), a mitoKATP channel opener, instead of sevoflurane. The cerebral infarct volume, neurological score and motor coordination were evaluated 24 h after reperfusion. The HF‑fed rats had larger infarct volumes, and lower neurological scores than the LF‑fed rats and also failed to respond to neuroprotection by sevoflurane or DZX. By contrast, sevoflurane and DZX reduced the infarct volumes and improved the neurological scores and motor coordination in the LF‑fed rats. Pretreatment with 5‑HD inhibited sevoflurane‑induced neuroprotection in the LF‑fed rats, whereas it had no effect in the HF‑fed rats. Molecular studies demonstrated that the expression of Kir6.2, a significant mitoKATP channel component, was reduced in the brains of the HF‑fed rats compared with the LF‑fed rats. The results of this study indicate that diet‑induced obesity eliminates the ability of anesthetic sevoflurane postconditioning to protect the brain against cerebral ischemic neuronal injury, most likely due to an impaired brain

Protective Mechanism of STAT3-siRNA on Cerebral Ischemia Injury

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He, Jinting; Yang, Le; Liang, Wenzhao

2018-01-01

Nerve cells in ischemic brain injury will occur a series of complex signal transduction pathway changes and produce the corresponding biological function, thus affecting the central nervous system functionally different cells in the ischemic brain injury metabolism, division, Differentiation and death process, while changes in signal pathways also play an important role in the repair process of the post-ischemic nervous system. JAK/STAT pathway and vascular lesions have some relevance, but its exact mechanism after cerebral ischemia is not yet fully understood. This study is intended to further explore the JAK / STAT pathway in the functional site of STAT3 in neuronal ischemia Hypoxic injury and related molecular mechanisms, targeting these targets design intervention strategies to block the signal pathway, in order to provide a theoretical basis for the treatment of ischemic brain damage in this pathway.

LncRNA FIRRE/NF-kB feedback loop contributes to OGD/R injury of cerebral microglial cells.

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Zang, Yunhua; Zhou, Xiyan; Wang, Qun; Li, Xia; Huang, Hailiang

2018-04-28

Stroke is one of the leading causes for serious long-term neurological disability. LncRNAs have been investigated to be dysregulated in ischemic stroke. However, the underlying mechanisms of some specific lncRNAs have not been clearly clarified. To determine lncRNA-mediated regulatory mechanism in ischemic stroke, we constructed OGD/R injury model of cerebral microglial cells. Microarray analysis was carried out and analyzed that lncRNA functional intergenic repeating RNA element (FIRRE) was associated with OGD/R injury. Based on the molecular biotechnology, we demonstrated that FIRRE could activate NF-kB signal pathway. Meanwhile, the activated NF-kB promoted FIRRE expression in OGD/R-treated cerebral microglial cells. Therefore, FIRRE and NF-kB formed a positive feedback loop to promote the transcription of NLRP3 inflammasome, thus contributed to the OGD/R injury of cerebral microglial cells. All findings in this study may help to explore novel and specific therapeutic target for ischemic stroke. Copyright © 2018. Published by Elsevier Inc.

The Traditional Herbal Medicine, Dangkwisoo-San, Prevents Cerebral Ischemic Injury through Nitric Oxide-Dependent Mechanisms

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Ji Hyun Kim

2011-01-01

Full Text Available Dangkwisoo-San (DS is an herbal extract that is widely used in traditional Korean medicine to treat traumatic ecchymosis and pain by promoting blood circulation and relieving blood stasis. However, the effect of DS in cerebrovascular disease has not been examined experimentally. The protective effects of DS on focal ischemic brain were investigated in a mouse model. DS stimulated nitric oxide (NO production in human brain microvascular endothelial cells (HBMECs. DS (10–300 μg/mL produced a concentration-dependent relaxation in mouse aorta, which was significantly attenuated by the nitric oxide synthase (NOS inhibitor L-NAME, suggesting that DS causes vasodilation via a NO-dependent mechanism. DS increased resting cerebral blood flow (CBF, although it caused mild hypotension. To investigate the effect of DS on the acute cerebral injury, C57/BL6J mice received 90 min of middle cerebral artery occlusion followed by 22.5 h of reperfusion. DS administered 3 days before arterial occlusion significantly reduced cerebral infarct size by 53.7% compared with vehicle treatment. However, DS did not reduce brain infarction in mice treated with the relatively specific endothelial NOS (eNOS inhibitor, N5-(1-iminoethyl-L-ornithine, suggesting that the neuroprotective effect of DS is primarily endothelium-dependent. This correlated with increased phosphorylation of eNOS in the brains of DS-treated mice. DS acutely improves CBF in eNOS-dependent vasodilation and reduces infarct size in focal cerebral ischemia. These data provide causal evidence that DS is cerebroprotective via the eNOS-dependent production of NO, which ameliorates blood circulation.

Chronic Exposure to Subtherapeutic Antibiotics Aggravates Ischemic Stroke Outcome in Mice

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Xiao-Hui Dong

2017-10-01

Full Text Available Subtherapeutic antibiotics have been widely used in agriculture since the 1950s, which can be accumulated in human body through various approaches and may have long-term consequences. However, there is limited information about the link between chronic subtherapeutic antibiotic exposure and the outcome of ischemic brain injury. Here we showed that long-term treatment with subtherapeutic chlortetracycline, penicillin or vancomycin, which were widely used in agriculture approved by US Food and Drug Administration (FDA, could impair EPC functions, reduce ischemic brain angiogenesis and aggravate cerebral ischemic injury and long-term stroke outcomes in mice. In addition, transplantated EPCs from chronic antibiotic-treated mice showed a lower therapeutic effect on cerebral ischemic injury reduction and local angiogenesis promotion compared to those from control mice, and EPCs from the donor animals could integrate into the recipient ischemic brain in mice. Furthermore, transplanted EPCs might exert paracrine effects on cerebral ischemic injury reduction in mice, which could be impaired by chronic antibiotic exposure. In conclusion, chronic subtherapeutic antibiotic exposure aggravated cerebral ischemic injury in mice, which might be partly attributed to the impairment of both EPC-mediated angiogenesis and EPCs' paracrine effects. These findings reveal a previously unrecognized impact of chronic subtherapeutic antibiotic exposure on ischemic injury.

Ischemic preconditioning protects against ischemic brain injury

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Xiao-meng Ma

2016-01-01

Full Text Available In this study, we hypothesized that an increase in integrin αv ß 3 and its co-activator vascular endothelial growth factor play important neuroprotective roles in ischemic injury. We performed ischemic preconditioning with bilateral common carotid artery occlusion for 5 minutes in C57BL/6J mice. This was followed by ischemic injury with bilateral common carotid artery occlusion for 30 minutes. The time interval between ischemic preconditioning and lethal ischemia was 48 hours. Histopathological analysis showed that ischemic preconditioning substantially diminished damage to neurons in the hippocampus 7 days after ischemia. Evans Blue dye assay showed that ischemic preconditioning reduced damage to the blood-brain barrier 24 hours after ischemia. This demonstrates the neuroprotective effect of ischemic preconditioning. Western blot assay revealed a significant reduction in protein levels of integrin αv ß 3, vascular endothelial growth factor and its receptor in mice given ischemic preconditioning compared with mice not given ischemic preconditioning 24 hours after ischemia. These findings suggest that the neuroprotective effect of ischemic preconditioning is associated with lower integrin αv ß 3 and vascular endothelial growth factor levels in the brain following ischemia.

Pharmacokinetic Study of Piracetam in Focal Cerebral Ischemic Rats.

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Paliwal, Pankaj; Dash, Debabrata; Krishnamurthy, Sairam

2018-04-01

Cerebral ischemia affects hepatic enzymes and brain permeability extensively. Piracetam was investigated up to phase III of clinical trials and there is lack of data on brain penetration in cerebral ischemic condition. Thus, knowledge of the pharmacokinetics and brain penetration of piracetam during ischemic condition would aid to improve pharmacotherapeutics in ischemic stroke. Focal cerebral ischemia was induced by middle cerebral artery occlusion for 2 h in male Wistar rats followed by reperfusion. After 24 h of middle cerebral artery occlusion or 22 h of reperfusion, piracetam was administered for pharmacokinetic, brain penetration, and pharmacological experiments. In pharmacokinetic study, blood samples were collected at different time points after 200-mg/kg (oral) and 75-mg/kg (intravenous) administration of piracetam through right external jugular vein cannulation. In brain penetration study, the cerebrospinal fluid, systemic blood, portal blood, and brain samples were collected at pre-designated time points after 200-mg/kg oral administration of piracetam. In a separate experiment, the pharmacological effect of the single oral dose of piracetam in middle cerebral artery occlusion was assessed at a dose of 200 mg/kg. All the pharmacokinetic parameters of piracetam including area under curve (AUC 0-24 ), maximum plasma concentration (C max ), time to reach the maximum plasma concentration (t max ), elimination half-life (t 1/2 ), volume of distribution (V z ), total body clearance, mean residence time, and bioavailability were found to be similar in ischemic stroke condition except for brain penetration. Piracetam exposure (AUC 0-2 ) in brain and CSF were found to be 2.4- and 3.1-fold higher, respectively, in ischemic stroke compared to control rats. Piracetam significantly reduced infarct volume by 35.77% caused by middle cerebral artery occlusion. There was no change in the pharmacokinetic parameters of piracetam in the ischemic stroke model except for

Lateral intracerebroventricular injection of Apelin-13 inhibits apoptosis after cerebral ischemia/reperfusion injury

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Xiao-ge Yan

2015-01-01

Full Text Available Apelin-13 inhibits neuronal apoptosis caused by hydrogen peroxide, yet apoptosis following cerebral ischemia-reperfusion injury has rarely been studied. In this study, Apelin-13 (0.1 µg/g was injected into the lateral ventricle of middle cerebral artery occlusion model rats. TTC, TUNEL, and immunohistochemical staining showed that compared with the cerebral ischemia/reperfusion group, infarct volume and apoptotic cell number at the ischemic penumbra region were decreased in the Apelin-13 treatment group. Additionally, Apelin-13 treatment increased Bcl-2 immunoreactivity and decreased caspase-3 immunoreactivity. Our findings suggest that Apelin-13 is neuroprotective against cerebral ischemia/reperfusion injury through inhibition of neuronal apoptosis.

Cortical neurogenesis in adult rats after ischemic brain injury: most new neurons fail to mature

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Qing-quan Li

2015-01-01

Full Text Available The present study examines the hypothesis that endogenous neural progenitor cells isolated from the neocortex of ischemic brain can differentiate into neurons or glial cells and contribute to neural regeneration. We performed middle cerebral artery occlusion to establish a model of cerebral ischemia/reperfusion injury in adult rats. Immunohistochemical staining of the cortex 1, 3, 7, 14 or 28 days after injury revealed that neural progenitor cells double-positive for nestin and sox-2 appeared in the injured cortex 1 and 3 days post-injury, and were also positive for glial fibrillary acidic protein. New neurons were labeled using bromodeoxyuridine and different stages of maturity were identified using doublecortin, microtubule-associated protein 2 and neuronal nuclei antigen immunohistochemistry. Immature new neurons coexpressing doublecortin and bromodeoxyuridine were observed in the cortex at 3 and 7 days post-injury, and semi-mature and mature new neurons double-positive for microtubule-associated protein 2 and bromodeoxyuridine were found at 14 days post-injury. A few mature new neurons coexpressing neuronal nuclei antigen and bromodeoxyuridine were observed in the injured cortex 28 days post-injury. Glial fibrillary acidic protein/bromodeoxyuridine double-positive astrocytes were also found in the injured cortex. Our findings suggest that neural progenitor cells are present in the damaged cortex of adult rats with cerebral ischemic brain injury, and that they differentiate into astrocytes and immature neurons, but most neurons fail to reach the mature stage.

Reno-Cerebral Reflex Activates the Renin-Angiotensin System, Promoting Oxidative Stress and Renal Damage After Ischemia-Reperfusion Injury.

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Cao, Wei; Li, Aiqing; Li, Jiawen; Wu, Chunyi; Cui, Shuang; Zhou, Zhanmei; Liu, Youhua; Wilcox, Christopher S; Hou, Fan Fan

2017-09-01

A kidney-brain interaction has been described in acute kidney injury, but the mechanisms are uncertain. Since we recently described a reno-cerebral reflex, we tested the hypothesis that renal ischemia-reperfusion injury (IRI) activates a sympathetic reflex that interlinks the renal and cerebral renin-angiotensin axis to promote oxidative stress and progression of the injury. Bilateral ischemia-reperfusion activated the intrarenal and cerebral, but not the circulating, renin-angiotensin system (RAS), increased sympathetic activity in the kidney and the cerebral sympathetic regulatory regions, and induced brain inflammation and kidney injury. Selective renal afferent denervation with capsaicin or renal denervation significantly attenuated IRI-induced activation of central RAS and brain inflammation. Central blockade of RAS or oxidative stress by intracerebroventricular (ICV) losartan or tempol reduced the renal ischemic injury score by 65% or 58%, respectively, and selective renal afferent denervation or reduction of sympathetic tone by ICV clonidine decreased the score by 42% or 52%, respectively (all p renal damage and dysfunction persisted after controlling blood pressure with hydralazine. This study uncovered a novel reflex pathway between ischemic kidney and the brain that sustains renal oxidative stress and local RAS activation to promote ongoing renal damage. These data suggest that the renal and cerebral renin-angiotensin axes are interlinked by a reno-cerebral sympathetic reflex that is activated by ischemia-reperfusion, which contributes to ischemia-reperfusion-induced brain inflammation and worsening of the acute renal injury. Antioxid. Redox Signal. 27, 415-432.

Role of phosphoinositide 3-kinase in ischemic postconditioning-induced attenuation of cerebral ischemia-evoked behavioral deficits in mice.

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Rehni, Ashish K; Singh, Nirmal

2007-01-01

The present study has been designed to pharmacologically investigate the role of phosphoinositide 3-kinase in ischemic postconditioning-induced reversal of global cerebral ischemia and reperfusion-induced behavioral dysfunction in mice. Bilateral carotid artery occlusion for 10 min followed by reperfusion for 24 h was employed in the present study to produce ischemia and reperfusion-induced cerebral injury in mice. Short-term memory was evaluated using the elevated plus maze test. The inclined beam walking test was employed to assess motor incoordination. Bilateral carotid artery occlusion followed by reperfusion produced impaired short-term memory, motor co-ordination and lateral push response. Three episodes of carotid artery occlusion for a period of 10 s and reperfusion of 10 s (ischemic postconditioning) significantly prevented ischemia-reperfusion-induced behavioral deficit measured in terms of loss of short-term memory, motor coordination and lateral push response. Wortmannin (2 mg/kg, iv), a phosphoinositide 3-kinase inhibitor given 10 min before ischemia attenuated the beneficial effects of ischemic postconditioning. It may be concluded that beneficial effects of ischemic postconditioning on global cerebral ischemia and reperfusion-induced behavioral deficits may involve activation of phosphoinositide 3-kinase-linked pathway.

Ischemic lesions related to cerebral angiography: Evaluation by diffusion weighted MR imaging

International Nuclear Information System (INIS)

Kato, Koki; Tomura, Noriaki; Takahashi, Satoshi; Sakuma, Ikuo; Watarai, Jiro

2003-01-01

We examined the incidence of ischemic lesions occurring after cerebral angiography by means of diffusion weighted MR imaging (DWI). Fifty patients were included in this study. Balloon occlusion tests of the internal carotid artery were performed in 9 of the 50 patients. DWI was performed on the same day as the cerebral angiography or on the following day. No new neurological deficits were found after cerebral angiography. However, 13 of the 50 cases revealed new ischemic lesions after cerebral angiography. The incidence of ischemic lesions was significantly different between patients who underwent balloon occlusion tests and patients who did not. The incidence of ischemic lesions was not influenced by the duration of the procedure, use of additional catheters, total amount of contrast material or the type of contrast material. The incidence of clinically silent ischemic lesions related to cerebral angiography is greater than the incidence of neurological complications. In patients who underwent occlusion tests of the internal carotid artery, the incidence of silent lesions was significantly higher than in patients who did not. (orig.)

Changes of resting cerebral activities in subacute ischemic stroke patients

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Ping Wu

2015-01-01

Full Text Available This study aimed to detect the difference in resting cerebral activities between ischemic stroke patients and healthy participants, define the abnormal site, and provide new evidence for pathological mechanisms, clinical diagnosis, prognosis prediction and efficacy evaluation of ischemic stroke. At present, the majority of functional magnetic resonance imaging studies focus on the motor dysfunction and the acute stage of ischemic stroke. This study recruited 15 right-handed ischemic stroke patients at subacute stage (15 days to 11.5 weeks and 15 age-matched healthy participants. A resting-state functional magnetic resonance imaging scan was performed on each subject to detect cerebral activity. Regional homogeneity analysis was used to investigate the difference in cerebral activities between ischemic stroke patients and healthy participants. The results showed that the ischemic stroke patients had lower regional homogeneity in anterior cingulate and left cerebrum and higher regional homogeneity in cerebellum, left precuneus and left frontal lobe, compared with healthy participants. The experimental findings demonstrate that the areas in which regional homogeneity was different between ischemic stroke patients and healthy participants are in the cerebellum, left precuneus, left triangle inferior frontal gyrus, left inferior temporal gyrus and anterior cingulate. These locations, related to the motor, sensory and emotion areas, are likely potential targets for the neural regeneration of subacute ischemic stroke patients.

Monitoring of cerebral haemodynamics in newborn infants

DEFF Research Database (Denmark)

Liem, K Djien; Greisen, Gorm

2010-01-01

The most important cerebrovascular injuries in newborn infants, particularly in preterm infants, are cerebral haemorrhage and ischemic injury. The typical cerebral vascular anatomy and the disturbance of cerebral haemodynamics play important roles in the pathophysiology. The term 'cerebral haemod...

The TRIF-dependent signaling pathway is not required for acute cerebral ischemia/reperfusion injury in mice

International Nuclear Information System (INIS)

Hua, Fang; Wang, Jun; Sayeed, Iqbal; Ishrat, Tauheed; Atif, Fahim; Stein, Donald G.

2009-01-01

TIR domain-containing adaptor protein (TRIF) is an adaptor protein in Toll-like receptor (TLR) signaling pathways. Activation of TRIF leads to the activation of interferon regulatory factor 3 (IRF3) and nuclear factor kappa B (NF-κB). While studies have shown that TLRs are implicated in cerebral ischemia/reperfusion (I/R) injury and in neuroprotection against ischemia afforded by preconditioning, little is known about TRIF's role in the pathological process following cerebral I/R. The present study investigated the role that TRIF may play in acute cerebral I/R injury. In a mouse model of cerebral I/R induced by transient middle cerebral artery occlusion, we examined the activation of NF-κB and IRF3 signaling in ischemic cerebral tissue using ELISA and Western blots. Neurological function and cerebral infarct size were also evaluated 24 h after cerebral I/R. NF-κB activity and phosphorylation of the inhibitor of kappa B (IκBα) increased in ischemic brains, but IRF3, inhibitor of κB kinase complex-ε (IKKε), and TANK-binding kinase1 (TBK1) were not activated after cerebral I/R in wild-type (WT) mice. Interestingly, TRIF deficit did not inhibit NF-κB activity or p-IκBα induced by cerebral I/R. Moreover, although cerebral I/R induced neurological and functional impairments and brain infarction in WT mice, the deficits were not improved and brain infarct size was not reduced in TRIF knockout mice compared to WT mice. Our results demonstrate that the TRIF-dependent signaling pathway is not required for the activation of NF-κB signaling and brain injury after acute cerebral I/R.

Cerebral hemodynamics in adult ischemic-type patients with moyamoya disease compared with those of atherothrombotic middle cerebral artery occlusion

International Nuclear Information System (INIS)

Idei, Masaru; Yamane, Kanji; Nishida, Masahiro; Manabe, Kazufumi; Yokota, Akira

2005-01-01

We measured regional cerebral blood flow (rCBF) in adult ischemic-type patients with moyamoya disease and in patients with atherothrombotic middle cerebral artery occlusion (MCAO) to investigate cerebral hemodynamics in adult ischemic-type of moyamoya disease. In this study we measured rCBF and regional cerebro-vascular response (rCVR) using acetazolamide by Xe-non-enhanced CT. Our subjects consisted of 15 adult ischemic-type patients with moyamoya disease and 27 atherothrombotic stroke patients with proximal occlusion of the middle cerebral artery. The region of inter est was conducted in the anterior cerebral artery, middle cerebral artery and posterior cerebral artery territories as well as basal ganglia regions. rGBF was preserved in all regions of patients with moyamoya disease. However, rCVR severely decreased in the anterior circulation territory in patients with moyamoya disease compared with those of MCAO. These results suggest that rCBF in the anterior circulation territory of adult ischemic-type patients with moyamoya disease is preserved by vasodilation of the cerebral arteries, while cerebral hemodynamic reserve capacity is severely reduced. The results indicated that basal moyamoya vessels are dilated. These findings may be one of the reasons why stroke occurs more frequently in adult than child patients with moyamoya disease. (author)

Neurovascular regulation in the ischemic brain.

Science.gov (United States)

Jackman, Katherine; Iadecola, Costantino

2015-01-10

The brain has high energetic requirements and is therefore highly dependent on adequate cerebral blood supply. To compensate for dangerous fluctuations in cerebral perfusion, the circulation of the brain has evolved intrinsic safeguarding measures. The vascular network of the brain incorporates a high degree of redundancy, allowing the redirection and redistribution of blood flow in the event of vascular occlusion. Furthermore, active responses such as cerebral autoregulation, which acts to maintain constant cerebral blood flow in response to changing blood pressure, and functional hyperemia, which couples blood supply with synaptic activity, allow the brain to maintain adequate cerebral perfusion in the face of varying supply or demand. In the presence of stroke risk factors, such as hypertension and diabetes, these protective processes are impaired and the susceptibility of the brain to ischemic injury is increased. One potential mechanism for the increased injury is that collateral flow arising from the normally perfused brain and supplying blood flow to the ischemic region is suppressed, resulting in more severe ischemia. Approaches to support collateral flow may ameliorate the outcome of focal cerebral ischemia by rescuing cerebral perfusion in potentially viable regions of the ischemic territory.

Sodium phenylbutyrate ameliorates focal cerebral ischemic/reperfusion injury associated with comorbid type 2 diabetes by reducing endoplasmic reticulum stress and DNA fragmentation.

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Srinivasan, Krishnamoorthy; Sharma, Shyam S

2011-11-20

Endoplasmic reticulum (ER) stress has been postulated to play a crucial role in the pathophysiology of cerebral ischemic/reperfusion (I/R) injury and diabetes. Diabetes is a major risk factor and also common amongst the people who suffer from stroke. In this study, we have investigated the neuroprotective potential of sodium 4-phenylbutyrate (SPB; 30-300mg/kg), a chemical chaperone by targeting ER stress in a rat model of transient focal cerebral ischemia associated with comorbid type 2 diabetes. Intraperitoneal treatment with SPB (100 and 300mg/kg) significantly ameliorated brain I/R damage as evidenced by reduction in cerebral infarct and edema volume. It also significantly improved the functional recovery of various neurobehavioral impairments (neurological deficit score, grip strength and rota rod) evoked by I/R compared with vehicle-treatment. Further, SPB (100mg/kg) significantly reduced the DNA fragmentation as shown by prominent reduction in terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells. This effect was observed concomitantly with significant attenuation in upregulation of 78kDa glucose regulated protein (GRP78), CCAAT/enhancer binding protein homologous protein or growth arrest DNA damage-inducible gene 153 (CHOP/GADD153) and activation of caspase-12, specific markers of ER stress/apoptosis. The neuroprotection observed with SPB was independent of its effect on cerebral blood flow and blood glucose. In conclusion, this study demonstrates the neuroprotective effect of SPB owing to amelioration of ER stress and DNA fragmentation. It also suggest that targeting ER stress might offer a promising therapeutic approach and benefits against ischemic stroke associated with comorbid type 2 diabetes. Copyright © 2011 Elsevier B.V. All rights reserved.

Totarol prevents neuronal injury in vitro and ameliorates brain ischemic stroke: Potential roles of Akt activation and HO-1 induction

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Gao, Yuanxue; Xu, Xiaojun; Chang, Sai; Wang, Yunjie; Xu, Yazhou; Ran, Siqi [Jiangsu Key Laboratory of Drug Screening, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009 (China); Huang, Zhangjian [Jiangsu Key Laboratory of Drug Discovery for Metabolic Diseases, China Pharmaceutical University, Nanjing 210009 (China); Li, Ping [Jiangsu Key Laboratory of Drug Screening, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009 (China); Li, Jia [National Center for Drug Screening, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, 189 Guo Shoujing Road, Shanghai 201203 (China); Zhang, Luyong [Jiangsu Key Laboratory of Drug Screening, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009 (China); Saavedra, Juan M. [Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC 20057 (United States); Liao, Hong, E-mail: liaohong56@hotmail.com [Jiangsu Key Laboratory of Drug Screening, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009 (China); Pang, Tao, E-mail: tpang@cpu.edu.cn [Jiangsu Key Laboratory of Drug Screening, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009 (China); Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, DC 20057 (United States)

2015-12-01

The natural product totarol, a phenolic diterpenoid and a major constituent isolated from the sap of Podocarpus totara, has been reported to have a potent antimicrobial activity. In this study, we determined whether totarol possessed an additional neuroprotective activity in vitro and in vivo. We found that totarol prevented glutamate- and oxygen and glucose deprivation-induced neuronal death in primary rat cerebellar granule neuronal cells and cerebral cortical neurons. Totarol increased Akt and GSK-3β phosphorylation, Nrf2 and heme oxygenase-1 (HO-1) protein expressions and suppressed oxidative stress by increasing GSH and SOD activities. The PI3K/Akt inhibitor LY294002 prevented totarol neuroprotective effect by suppressing the totarol-induced changes in HO-1 expression and the activities of GSH and SOD. The HO-1 inhibitor ZnPPIX also prevented totarol-increased GSH and SOD activities. In a model of acute cerebral ischemic injury in Sprague–Dawley rats, produced by occlusion of the middle cerebral artery for 2 h followed by 22 h or 46 h of reperfusion, totarol significantly reduced infarct volume and improved the neurological deficit. In this model, totarol increased HO-1 expression and the activities of GSH and SOD. These observations suggest that totarol may be a novel activator of the Akt/HO-1 pathway protecting against ischemic stroke through reduction of oxidative stress. - Graphical abstract: It is unknown whether the natural product totarol has neuroprotective effects in vitro and in vivo. This study underscores that totarol prevents neuronal injury in vitro, not only by activating PI3K/Akt pathway, but also via induction of Nrf2, HO-1, GSH and SOD expressions. Totarol also ameliorated acute cerebral ischemic injury in a rat ischemic stroke model. The findings highlight that totarol may be exploited for protecting against ischemic stroke through Akt/HO-1 pathway. - Highlights: • Totarol protects glutamate- and OGD-induced neuronal injury in vitro. �

Totarol prevents neuronal injury in vitro and ameliorates brain ischemic stroke: Potential roles of Akt activation and HO-1 induction

International Nuclear Information System (INIS)

Gao, Yuanxue; Xu, Xiaojun; Chang, Sai; Wang, Yunjie; Xu, Yazhou; Ran, Siqi; Huang, Zhangjian; Li, Ping; Li, Jia; Zhang, Luyong; Saavedra, Juan M.; Liao, Hong; Pang, Tao

2015-01-01

The natural product totarol, a phenolic diterpenoid and a major constituent isolated from the sap of Podocarpus totara, has been reported to have a potent antimicrobial activity. In this study, we determined whether totarol possessed an additional neuroprotective activity in vitro and in vivo. We found that totarol prevented glutamate- and oxygen and glucose deprivation-induced neuronal death in primary rat cerebellar granule neuronal cells and cerebral cortical neurons. Totarol increased Akt and GSK-3β phosphorylation, Nrf2 and heme oxygenase-1 (HO-1) protein expressions and suppressed oxidative stress by increasing GSH and SOD activities. The PI3K/Akt inhibitor LY294002 prevented totarol neuroprotective effect by suppressing the totarol-induced changes in HO-1 expression and the activities of GSH and SOD. The HO-1 inhibitor ZnPPIX also prevented totarol-increased GSH and SOD activities. In a model of acute cerebral ischemic injury in Sprague–Dawley rats, produced by occlusion of the middle cerebral artery for 2 h followed by 22 h or 46 h of reperfusion, totarol significantly reduced infarct volume and improved the neurological deficit. In this model, totarol increased HO-1 expression and the activities of GSH and SOD. These observations suggest that totarol may be a novel activator of the Akt/HO-1 pathway protecting against ischemic stroke through reduction of oxidative stress. - Graphical abstract: It is unknown whether the natural product totarol has neuroprotective effects in vitro and in vivo. This study underscores that totarol prevents neuronal injury in vitro, not only by activating PI3K/Akt pathway, but also via induction of Nrf2, HO-1, GSH and SOD expressions. Totarol also ameliorated acute cerebral ischemic injury in a rat ischemic stroke model. The findings highlight that totarol may be exploited for protecting against ischemic stroke through Akt/HO-1 pathway. - Highlights: • Totarol protects glutamate- and OGD-induced neuronal injury in vitro. �

The TRIF-dependent signaling pathway is not required for acute cerebral ischemia/reperfusion injury in mice

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Hua, Fang, E-mail: fhua2@emory.edu [Department of Emergency Medicine, Brain Research Laboratory, Emory University School of Medicine, 1365B Clifton Road, Suite 5100, Atlanta, GA 30322 (United States); Wang, Jun; Sayeed, Iqbal; Ishrat, Tauheed; Atif, Fahim; Stein, Donald G. [Department of Emergency Medicine, Brain Research Laboratory, Emory University School of Medicine, 1365B Clifton Road, Suite 5100, Atlanta, GA 30322 (United States)

2009-12-18

TIR domain-containing adaptor protein (TRIF) is an adaptor protein in Toll-like receptor (TLR) signaling pathways. Activation of TRIF leads to the activation of interferon regulatory factor 3 (IRF3) and nuclear factor kappa B (NF-{kappa}B). While studies have shown that TLRs are implicated in cerebral ischemia/reperfusion (I/R) injury and in neuroprotection against ischemia afforded by preconditioning, little is known about TRIF's role in the pathological process following cerebral I/R. The present study investigated the role that TRIF may play in acute cerebral I/R injury. In a mouse model of cerebral I/R induced by transient middle cerebral artery occlusion, we examined the activation of NF-{kappa}B and IRF3 signaling in ischemic cerebral tissue using ELISA and Western blots. Neurological function and cerebral infarct size were also evaluated 24 h after cerebral I/R. NF-{kappa}B activity and phosphorylation of the inhibitor of kappa B (I{kappa}B{alpha}) increased in ischemic brains, but IRF3, inhibitor of {kappa}B kinase complex-{epsilon} (IKK{epsilon}), and TANK-binding kinase1 (TBK1) were not activated after cerebral I/R in wild-type (WT) mice. Interestingly, TRIF deficit did not inhibit NF-{kappa}B activity or p-I{kappa}B{alpha} induced by cerebral I/R. Moreover, although cerebral I/R induced neurological and functional impairments and brain infarction in WT mice, the deficits were not improved and brain infarct size was not reduced in TRIF knockout mice compared to WT mice. Our results demonstrate that the TRIF-dependent signaling pathway is not required for the activation of NF-{kappa}B signaling and brain injury after acute cerebral I/R.

Current status and outlook of endovascular therapy for cerebral ischemic diseases

International Nuclear Information System (INIS)

Li Minghua; Zhao Jungong

2005-01-01

Improvement of diagnostic technology and increasing advent of new materials for intervention has created a new area for endovascular therapy of cerebral ischemic diseases. Current research findings have shown that endovascular thrombolysis in acute stage of cerebral infarction can accelerate the rate of re-canalization of occluded arteries and greatly decrease the morbidity and mortality of cerebral ischemic vascular diseases. Stenting of arterial stenosis can the improve of blood supply distal to the lesion, prevent recurrent cerebral ischemic stroke. As a result, endovascular thrombolysis for acute cerebral infarction and stenting for intracranial and carotid arterial stenosis are booming both at home and abroad. Proper selection of patients of acute cerebral infarction for endovascular thrombolysis with less complications could be achieved through CT perfusion, MR perfusion-weighted image (PWI) and diffusion-weighted image (DWI), non-invasive vascular imaging technology including CEMRA and CTA for confirming and demonstrating the sites and causes of cerebral ischemia, and furthermore for evaluating the survival ability and etc. The research team administered albumin and magnesium sulfate as neurological protection drug to treat rat infarction model within 6 hours of onset resulting with the same effect of decreasing the damage of ischemic cerebral tissue and without hemorrhagic complication. It is certain that hemorrhagic complication in thrombolysis is a result of multiple factors with no single drug being able to solve the problem. It is predictable that, based on semi-quantitative or quantitative parameters of CT or MRI in conjunction with PWI/DWI mismatch model rather than simply on the onset time of infarction for proper selection of patients of cerebral infarction, mechanic thrombus-disruption and/or intra-arterial thrombolysis together with intervention of neurological protection drug will be the trend for treating acute cerebral infarction in the future

Early cerebral hemodynamic, metabolic and histological changes in hypoxic-ischemic fetal lambs during postnatal life

Directory of Open Access Journals (Sweden)

Carmen eRey-Santano

2011-09-01

Full Text Available The hemodynamic, metabolic and biochemical changes produce during transition from fetal to neonatal life could be aggravated if asphyctic event occur during fetal life. The aim of the study was to examine the regional cerebral blood flow (RCBF, histological changes, and cerebral brain metabolism in preterm lambs, and to analyze the role of oxidative stress for the first hours of postnatal life following severe fetal asphyxia. 18 chronically instrumented fetal lambs were assigned to: hypoxic-ischemic group, following fetal asphyxia animals were delivered and maintained on intermittent-positive-pressure-ventilation for 3 hours, and non-injured animals that were managed similarly to the previous group and used as control group. During hypoxic-ischemic insult, injured group developed acidosis, hypoxia, hypercapnia, latacidaemia and tachycardia in comparison to control group, without hypotension. Intermittent-positive-pressure-ventilation transiently improved gas exchange and cardiovascular parameters. After HI injury and during ventilation-support, the increased RCBF in inner zones was maintained for hypoxic-ischemic group, but cortical flow did not exhibit differences compared to the control group. Also, the increase of TUNEL positive cells (apoptosis and antioxidant enzymes, and decrease of ATP reserves was significantly higher in the brain regions where the RCBF were not increased.In conclusion, early metabolic, histological and hemodynamic changes involved in brain damage have been intensively investigated and reported in premature asphyctic lambs for the first 3 hours of postnatal life. Those changes have been described in human neonates, so our model could be useful to test the security and the effectiveness of different neuroprotective or ventilatory strategies when are applied in the first hours after fetal hypoxic-ischemic injury.

Establishment of modified reversible regional cerebral ischemic models

International Nuclear Information System (INIS)

Ji Xunming; Ling Feng; Zhao Xiqing; Xuan Yun; Wang Yueqin; Ling Xiaolan; Chang Hongjun; Zhang Zhiping

2005-01-01

Objective: Modifying the method of establishing reversible middle cerebral ischemic models in rats for improvement of the stability and rate of success, so as to raise the reliability of cerebral ischemic study. Methods: Sixty male Wistar rats were randomly divided into two groups, modified and control groups, 30 rats in each group. The method of silicone- tipping on one end of the nylon suture was used to modify the establishment of embolus, and tip-heating method was used to establish the traditional embolus with all the other steps of the procedure just the same. The Zea Longa 5 scoring scale was used to estimate the neurological deficiency while TTC staining method was used to measure and calculate the volume of cerebral infarction. The percentage of successful models with 3-4 grade scorings and the coefficient of the variations of cerebral infarct volume were used to estimate the stability of the models. Results: The rate of success of establishment models in the modification group was significantly higher in comparing with the traditional group (93% vs 60%, χ 2 =9.32, P=0.002). The percentage of model establishment with 3-4 grade neurological scores in modification group was higher than that in the traditional group 96.4% vs 61.2%, χ 2 =9.51, P=0.002). The cerebral infarct volume in modification group and traditional group were (4.1450±0.5019) cm 3 and (3.8435 ± 0.8164) cm 3 , and the coefficients of variation were 12.01% and 21.24% respectively, which indicated that the stability of models was significantly higher in modification group than in the traditional one. Conclusions: The rates of success and stability of the models for reversible focal cerebral ischemia made by the modification method were significantly improved, with decreasing the cost of model creation and increasing the accuracy of study of ischemic cerebral vascular disease. (authors)

Cardiovascular risk factors cause premature rarefaction of the collateral circulation and greater ischemic tissue injury.

Science.gov (United States)

Moore, Scott M; Zhang, Hua; Maeda, Nobuyo; Doerschuk, Claire M; Faber, James E

2015-07-01

Collaterals lessen tissue injury in occlusive disease. However, aging causes progressive decline in their number and smaller diameters in those that remain (collateral rarefaction), beginning at 16 months of age in mice (i.e., middle age), and worse ischemic injury-effects that are accelerated in even 3-month-old eNOS(-/-) mice. These findings have found indirect support in recent human studies. We sought to determine whether other cardiovascular risk factors (CVRFs) associated with endothelial dysfunction cause collateral rarefaction, investigate possible mechanisms, and test strategies for prevention. Mice with nine different models of CVRFs of 4-12 months of age were assessed for number and diameter of native collaterals in skeletal muscle and brain and for collateral-dependent perfusion and ischemic injury after arterial occlusion. Hypertension caused collateral rarefaction whose severity increased with duration and level of hypertension, accompanied by greater hindlimb ischemia and cerebral infarct volume. Chronic treatment of wild-type mice with L-N (G)-nitro-arginine methylester caused similar rarefaction and worse ischemic injury which were not prevented by lowering arterial pressure with hydralazine. Metabolic syndrome, hypercholesterolemia, diabetes mellitus, and obesity also caused collateral rarefaction. Neither chronic statin treatment nor exercise training lessened hypertension-induced rarefaction. Chronic CVRF presence caused collateral rarefaction and worse ischemic injury, even at relatively young ages. Rarefaction was associated with increased proliferation rate of collateral endothelial cells, effects that may promote accelerated endothelial cell senescence.

Curcumin Protects Neuron against Cerebral Ischemia-Induced Inflammation through Improving PPAR-Gamma Function

OpenAIRE

Zun-Jing Liu; Wei Liu; Lei Liu; Cheng Xiao; Yu Wang; Jing-Song Jiao

2013-01-01

Cerebral ischemia is the most common cerebrovascular disease worldwide. Recent studies have demonstrated that curcumin had beneficial effect to attenuate cerebral ischemic injury. However, it is unclear how curcumin protects against cerebral ischemic injury. In the present study, using rat middle cerebral artery occlusion model, we found that curcumin was a potent PPAR ? agonist in that it upregulated PPAR ? expression and PPAR ? -PPRE binding activity. Administration of curcumin markedly dec...

Paradigms and mechanisms of inhalational anesthetics mediated neuroprotection against cerebral ischemic stroke

OpenAIRE

Wang, Hailian; Li, Peiying; Xu, Na; Zhu, Ling; Cai, Mengfei; Yu, Weifeng; Gao, Yanqin

2016-01-01

Cerebral ischemic stroke is a leading cause of serious long-term disability and cognitive dysfunction. The high mortality and disability of cerebral ischemic stroke is urging the health providers, including anesthesiologists and other perioperative professioners, to seek effective protective strategies, which are extremely limited, especially for those perioperative patients. Intriguingly, several commonly used inhalational anesthetics are recently suggested to possess neuroprotective effects...

MR findings of cerebral palsy: comparison between preterm patients and fullterm patients

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Hwang, Yoon Joon; Kim, Dong Ik; Yoon, Pyeong Ho; Jeon, Pyoung; Ryu, Young Hoon; Hwang, Geum Ju; Kim, Eun Kyung [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of); Lee, Byung Hee [Pundang Cha General Hospital, Sungnam (Korea, Republic of)

1997-09-01

To observe the MR findings of cerebral palsy by evaluating cerebral damage resulting from hypoxic ischemic injury and other variable causes and to compare the findings between preterm and full-term patients. We reviewed the MR findings of 102 cerebral palsy patients (71 full-term and 31 preterm). These were analysed with regard to deep and peripheral white matter, gray matter, basal ganglia, the thalamus, brainstem, cerebellum, corpus callosum and ventricles, according to the pattern of injury such as hypoxic ischemic injury, migration anomaly and early intrauterine injury, the findings of full-term and preterm patients were then compared. MR findings of preterm patients(n=3D31) were as follows;hypoxic ischemic injury(n=3D26),normal(n=3D2), and migration anomaly(n=3D3), while those of full-term patients(n=3D71) were hypoxic ischemic injury(n=3D41), normal(n=3D24), migration anomaly(n=3D4), early uterine injury(n=3D2), and perirolandic ischemic injury(n=3D6);in 5 patients, this latter condition was combined with status marmoratus. Periventricular leukomalacia was the most common finding in both preterm patients and full-term patients;selective neuronal necrosis, parasagittal injury and perirolandic injury were observed only in full-term patients. On MRI, variable findings of cerebral palsy were clearly observed;periventricular leukomalacia was the most common finding in both preterm and full-term patients.=20.

MR findings of cerebral palsy: comparison between preterm patients and fullterm patients

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Hwang, Yoon Joon; Kim, Dong Ik; Yoon, Pyeong Ho; Jeon, Pyoung; Ryu, Young Hoon; Hwang, Geum Ju; Kim, Eun Kyung; Lee, Byung Hee

1997-01-01

To observe the MR findings of cerebral palsy by evaluating cerebral damage resulting from hypoxic ischemic injury and other variable causes and to compare the findings between preterm and full-term patients. We reviewed the MR findings of 102 cerebral palsy patients (71 full-term and 31 preterm). These were analysed with regard to deep and peripheral white matter, gray matter, basal ganglia, the thalamus, brainstem, cerebellum, corpus callosum and ventricles, according to the pattern of injury such as hypoxic ischemic injury, migration anomaly and early intrauterine injury, the findings of full-term and preterm patients were then compared. MR findings of preterm patients(n=3D31) were as follows;hypoxic ischemic injury(n=3D26),normal(n=3D2), and migration anomaly(n=3D3), while those of full-term patients(n=3D71) were hypoxic ischemic injury(n=3D41), normal(n=3D24), migration anomaly(n=3D4), early uterine injury(n=3D2), and perirolandic ischemic injury(n=3D6);in 5 patients, this latter condition was combined with status marmoratus. Periventricular leukomalacia was the most common finding in both preterm patients and full-term patients;selective neuronal necrosis, parasagittal injury and perirolandic injury were observed only in full-term patients. On MRI, variable findings of cerebral palsy were clearly observed;periventricular leukomalacia was the most common finding in both preterm and full-term patients.=20

Rapamycin preconditioning attenuates transient focal cerebral ischemia/reperfusion injury in mice.

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Yin, Lele; Ye, Shasha; Chen, Zhen; Zeng, Yaoying

2012-12-01

Rapamycin, an mTOR inhibitor and immunosuppressive agent in clinic, has protective effects on traumatic brain injury and neurodegenerative diseases. But, its effects on transient focal ischemia/reperfusion disease are not very clear. In this study, we examined the effects of rapamycin preconditioning on mice treated with middle cerebral artery occlusion/reperfusion operation (MCAO/R). We found that the rapamycin preconditioning by intrahippocampal injection 20 hr before MCAO/R significantly improved the survival rate and longevity of mice. It also decreased the neurological deficit score, infracted areas and brain edema. In addition, rapamycin preconditioning decreased the production of NF-κB, TNF-α, and Bax, but not Bcl-2, an antiapoptotic protein in the ischemic area. From these results, we may conclude that rapamycin preconditioning attenuate transient focal cerebral ischemia/reperfusion injury and inhibits apoptosis induced by MCAO/R in mice.

Quantification of ante-mortem hypoxic ischemic brain injury by post-mortem cerebral magnetic resonance imaging in neonatal encephalopathy.

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Montaldo, Paolo; Chaban, Badr; Lally, Peter J; Sebire, Neil J; Taylor, Andrew M; Thayyil, Sudhin

2015-11-01

Post-mortem (PM) magnetic resonance imaging (MRI) is increasingly used as an alternative to conventional autopsy in babies dying from neonatal encephalopathy. However, the confounding effect of post-mortem changes on the detection of ante-mortem ischemic injury is unclear. We examined whether quantitative MR measurements can accurately distinguish ante-mortem ischemic brain injury from artifacts using post-mortem MRI. We compared PM brain MRI (1.5 T Siemens, Avanto) in 7 infants who died with neonatal encephalopathy (NE) of presumed hypoxic-ischemic origin with 7 newborn infants who had sudden unexplained neonatal death (SUND controls) without evidence of hypoxic-ischemic brain injury at autopsy. We measured apparent diffusion coefficients (ADCs), T1-weighted signal intensity ratios (SIRs) compared to vitreous humor and T2 relaxation times from 19 predefined brain areas typically involved in neonatal encephalopathy. There were no differences in mean ADC values, SIRs on T1-weighted images or T2 relaxation times in any of the 19 predefined brain areas between NE and SUND infants. All MRI images showed loss of cortical gray/white matter differentiation, loss of the normal high signal intensity (SI) in the posterior limb of the internal capsule on T1-weighted images, and high white matter SI on T2-weighted images. Normal post-mortem changes may be easily mistaken for ante-mortem ischemic injury, and current PM MRI quantitative assessment cannot reliably distinguish these. These findings may have important implications for appropriate interpretation of PM imaging findings, especially in medico-legal practice. Copyright © 2015 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

Attenuation of Cerebral Ischemic Injury in Smad1 Deficient Mice.

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Jamie K Wong

Full Text Available Stroke results in brain tissue damage from ischemia and oxidative stress. Molecular regulators of the protective versus deleterious cellular responses after cerebral ischemia remain to be identified. Here, we show that deletion of Smad1, a conserved transcription factor that mediates canonical bone morphogenetic protein (BMP signaling, results in neuroprotection in an ischemia-reperfusion (I/R stroke model. Uninjured mice with conditional deletion of Smad1 in the CNS (Smad1 cKO displayed upregulation of the reactive astrocyte marker GFAP and hypertrophic morphological changes in astrocytes compared to littermate controls. Additionally, cultured Smad1(-/- astrocytes exhibited an enhanced antioxidant capacity. When subjected to I/R injury by transient middle cerebral artery occlusion (tMCAO, Smad1 cKO mice showed enhanced neuronal survival and improved neurological recovery at 7 days post-stroke. This neuroprotective phenotype is associated with attenuated reactive astrocytosis and neuroinflammation, along with reductions in oxidative stress, p53 induction, and apoptosis. Our data suggest that Smad1-mediated signaling pathway is involved in stroke pathophysiology and may present a new potential target for stroke therapy.

Toll-like receptor 2 deficiency leads to delayed exacerbation of ischemic injury

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Bohacek Ivan

2012-08-01

Full Text Available Abstract Background Using a live imaging approach, we have previously shown that microglia activation after stroke is characterized by marked and long-term induction of the Toll-like receptor (TLR 2 biophotonic signals. However, the role of TLR2 (and potentially other TLRs beyond the acute innate immune response and as early neuroprotection against ischemic injury is not well understood. Methods TLR2−/− mice were subjected to transient middle cerebral artery occlusion followed by different reperfusion times. Analyses assessing microglial activation profile/innate immune response were performed using in situ hybridization, immunohistochemistry analysis, flow cytometry and inflammatory cytokine array. The effects of the TLR2 deficiency on the evolution of ischemic brain injury were analyzed using a cresyl violet staining of brain sections with appropriate lesion size estimation. Results Here we report that TLR2 deficiency markedly affects post-stroke immune response resulting in delayed exacerbation of the ischemic injury. The temporal analysis of the microglia/macrophage activation profiles in TLR2−/− mice and age-matched controls revealed reduced microglia/macrophage activation after stroke, reduced capacity of resident microglia to proliferate as well as decreased levels of monocyte chemotactic protein-1 (MCP-1 and consequently lower levels of CD45high/CD11b+ expressing cells as shown by flow cytometry analysis. Importantly, although acute ischemic lesions (24 to 72 h were smaller in TLR2−/− mice, the observed alterations in innate immune response were more pronounced at later time points (at day 7 after initial stroke, which finally resulted in delayed exacerbation of ischemic lesion leading to larger chronic infarctions as compared with wild-type mice. Moreover, our results revealed that TLR2 deficiency is associated with significant decrease in the levels of neurotrophic/anti-apoptotic factor Insulin-like growth factor-1 (IGF-1

Transcranial diffuse optical monitoring of microvascular cerebral hemodynamics after thrombolysis in ischemic stroke

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Zirak, Peyman; Delgado-Mederos, Raquel; Dinia, Lavinia; Carrera, David; Martí-Fàbregas, Joan; Durduran, Turgut

2014-01-01

The ultimate goal of therapeutic strategies for ischemic stroke is to reestablish the blood flow to the ischemic region of the brain. However, currently, the local cerebral hemodynamics (microvascular) is almost entirely inaccessible for stroke clinicians at the patient bed-side, and the recanalization of the major cerebral arteries (macrovascular) is the only available measure to evaluate the therapy, which does not always reflect the local conditions. Here we report the case of an ischemic stroke patient whose microvascular cerebral blood flow and oxygenation were monitored by a compact hybrid diffuse optical monitor during thrombolytic therapy. This monitor combined diffuse correlation spectroscopy and near-infrared spectroscopy. The reperfusion assessed by hybrid diffuse optics temporally correlated with the recanalization of the middle cerebral artery (assessed by transcranial-Doppler) and was in agreement with the patient outcome. This study suggests that upon further investigation, diffuse optics might have a potential for bed-side acute stroke monitoring and therapy guidance by providing hemodynamics information at the microvascular level.

Nicotinamide mononucleotide inhibits post-ischemic NAD(+) degradation and dramatically ameliorates brain damage following global cerebral ischemia.

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Park, Ji H; Long, Aaron; Owens, Katrina; Kristian, Tibor

2016-11-01

Nicotinamide adenine dinucleotide (NAD(+)) is an essential cofactor for multiple cellular metabolic reactions and has a central role in energy production. Brain ischemia depletes NAD(+) pools leading to bioenergetics failure and cell death. Nicotinamide mononucleotide (NMN) is utilized by the NAD(+) salvage pathway enzyme, nicotinamide adenylyltransferase (Nmnat) to generate NAD(+). Therefore, we examined whether NMN could protect against ischemic brain damage. Mice were subjected to transient forebrain ischemia and treated with NMN or vehicle at the start of reperfusion or 30min after the ischemic insult. At 2, 4, and 24h of recovery, the proteins poly-ADP-ribosylation (PAR), hippocampal NAD(+) levels, and expression levels of NAD(+) salvage pathway enzymes were determined. Furthermore, animal's neurologic outcome and hippocampal CA1 neuronal death was assessed after six days of reperfusion. NMN (62.5mg/kg) dramatically ameliorated the hippocampal CA1 injury and significantly improved the neurological outcome. Additionally, the post-ischemic NMN treatment prevented the increase in PAR formation and NAD(+) catabolism. Since the NMN administration did not affect animal's temperature, blood gases or regional cerebral blood flow during recovery, the protective effect was not a result of altered reperfusion conditions. These data suggest that administration of NMN at a proper dosage has a strong protective effect against ischemic brain injury. Published by Elsevier Inc.

Neuroprotection by curcumin in ischemic brain injury involves the Akt/Nrf2 pathway.

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Jingxian Wu

Full Text Available Oxidative damage plays a critical role in many diseases of the central nervous system. This study was conducted to determine the molecular mechanisms involved in the putative anti-oxidative effects of curcumin against experimental stroke. Oxygen and glucose deprivation/reoxygenation (OGD/R was used to mimic ischemic insult in primary cultured cortical neurons. A rapid increase in the intracellular expression of NAD(PH: quinone oxidoreductase1 (NQO1 induced by OGD was counteracted by curcumin post-treatment, which paralleled attenuated cell injury. The reduction of phosphorylation Akt induced by OGD was restored by curcumin. Consequently, NQO1 expression and the binding activity of nuclear factor-erythroid 2-related factor 2 (Nrf2 to antioxidant response element (ARE were increased. LY294002 blocked the increase in phospho-Akt evoked by curcumin and abolished the associated protective effect. Adult male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion for 60 minutes. Curcumin administration significantly reduced infarct size. Curcumin also markedly reduced oxidative stress levels in middle cerebral artery occlusion (MCAO rats; hence, these effects were all suppressed by LY294002. Taken together, these findings provide evidence that curcumin protects neurons against ischemic injury, and this neuroprotective effect involves the Akt/Nrf2 pathway. In addition, Nrf2 is involved in the neuroprotective effects of curcumin against oxidative damage.

Neuroprotection by Curcumin in Ischemic Brain Injury Involves the Akt/Nrf2 Pathway

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Wu, Jingxian; Li, Qiong; Wang, Xiaoyan; Yu, Shanshan; Li, Lan; Wu, Xuemei; Chen, Yanlin; Zhao, Jing; Zhao, Yong

2013-01-01

Oxidative damage plays a critical role in many diseases of the central nervous system. This study was conducted to determine the molecular mechanisms involved in the putative anti-oxidative effects of curcumin against experimental stroke. Oxygen and glucose deprivation/reoxygenation (OGD/R) was used to mimic ischemic insult in primary cultured cortical neurons. A rapid increase in the intracellular expression of NAD(P)H: quinone oxidoreductase1 (NQO1) induced by OGD was counteracted by curcumin post-treatment, which paralleled attenuated cell injury. The reduction of phosphorylation Akt induced by OGD was restored by curcumin. Consequently, NQO1 expression and the binding activity of nuclear factor-erythroid 2-related factor 2 (Nrf2) to antioxidant response element (ARE) were increased. LY294002 blocked the increase in phospho-Akt evoked by curcumin and abolished the associated protective effect. Adult male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion for 60 minutes. Curcumin administration significantly reduced infarct size. Curcumin also markedly reduced oxidative stress levels in middle cerebral artery occlusion (MCAO) rats; hence, these effects were all suppressed by LY294002. Taken together, these findings provide evidence that curcumin protects neurons against ischemic injury, and this neuroprotective effect involves the Akt/Nrf2 pathway. In addition, Nrf2 is involved in the neuroprotective effects of curcumin against oxidative damage. PMID:23555802

Treadmill exercise promotes neuroprotection against cerebral ischemia–reperfusion injury via downregulation of pro-inflammatory mediators

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Zhang Y

2016-12-01

Full Text Available Ying Zhang,1,* Richard Y Cao,2,* Xinling Jia,3,* Qing Li,1 Lei Qiao,1 Guofeng Yan,4 Jian Yang1 1Department of Rehabilitation, 2Laboratory of Immunology, Shanghai Xuhui Central Hospital, Shanghai Clinical Research Center, Chinese Academy of Sciences, 3School of Life sciences, Shanghai University, 4School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China *These authors contributed equally to this work Background: Stroke is one of the major causes of morbidity and mortality worldwide, which is associated with serious physical deficits that affect daily living and quality of life and produces immense public health and economic burdens. Both clinical and experimental data suggest that early physical training after ischemic brain injury may reduce the extent of motor dysfunction. However, the exact mechanisms have not been fully elucidated. The aim of this study was to investigate the effects of aerobic exercise on neuroprotection and understand the underlying mechanisms.Materials and methods: Middle cerebral artery occlusion (MCAO was conducted to establish a rat model of cerebral ischemia–reperfusion injury to mimic ischemic stroke. Experimental animals were divided into the following three groups: sham (n=34, MCAO (n=39, and MCAO plus treadmill exercise (n=28. The effects of aerobic exercise intervention on ischemic brain injury were evaluated using functional scoring, histological analysis, and Bio-Plex Protein Assays.Results: Early aerobic exercise intervention was found to improve motor function, prevent death of neuronal cells, and suppress the activation of microglial cells and astrocytes. Furthermore, it was observed that aerobic exercise downregulated the expression of the cytokine interleukin-1β and the chemokine monocyte chemotactic protein-1 after transient MCAO in experimental rats.Conclusion: This study demonstrates that treadmill exercise rehabilitation promotes neuroprotection against cerebral

CT fogging effect with ischemic cerebral infarcts

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Becker, H.; Desch, H.; Hacker, H.; Pencz, A.; Frankfurt Univ.

1979-01-01

Systematic CT studies on ten patients with persistent ischemic cerebral infarct revealed a constant phenomenon, the fogging effect. The hypodense infarct at the beginning will be isodense, or close to isodense, on the plain CT during the second or third week and at a later stage will be hypodense again. The fogging infarcted area shows homogeneous intensive contrast enhancement. Knowledge of the fogging effect is important for correct interpretation of the CT image and the indication for contrast medium CT. CT without contrast medium may lead to misinterpretation during the second and third week after the onset of cerebral infarction. (orig.) [de

CT fogging effect with ischemic cerebral infarcts

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Becker, H; Desch, H; Hacker, H; Pencz, A [Frankfurt Univ. (Germany, F.R.). Abt. fuer Neurologie; Frankfurt Univ. (Germany, F.R.). Abt. fuer Neuroradiologie)

1979-01-01

Systematic CT studies on ten patients with persistent ischemic cerebral infarct revealed a constant phenomenon, the fogging effect. The hypodense infarct at the beginning will be isodense, or close to isodense, on the plain CT during the second or third week and at a later stage will be hypodense again. The fogging infarcted area shows homogeneous intensive contrast enhancement. Knowledge of the fogging effect is important for correct interpretation of the CT image and the indication for contrast medium CT. CT without contrast medium may lead to misinterpretation during the second and third week after the onset of cerebral infarction.

Involvement of CCR-2 chemokine receptor activation in ischemic preconditioning and postconditioning of brain in mice.

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Rehni, Ashish K; Singh, Thakur Gurjeet

2012-10-01

The present study has been designed to investigate the potential role of CCR-2 chemokine receptor in ischemic preconditioning as well as postconditioning induced reversal of ischemia-reperfusion injury in mouse brain. Bilateral carotid artery occlusion of 17 min followed by reperfusion for 24h was employed in present study to produce ischemia and reperfusion induced cerebral injury in mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was evaluated using elevated plus-maze test and Morris water maze test. Rota rod test was employed to assess motor incoordination. Bilateral carotid artery occlusion followed by reperfusion produced cerebral infarction and impaired memory and motor co-ordination. Three preceding episodes of bilateral carotid artery occlusion for 1 min and reperfusion of 1 min were employed to elicit ischemic preconditioning of brain, while three episodes of bilateral carotid artery occlusion for 10s and reperfusion of 10s immediately after the completion of were employed to elicit ischemic postconditioning of brain. Both prior ischemic preconditioning as well as ischemic postconditioning immediately after global cerebral ischemia prevented markedly ischemia-reperfusion-induced cerebral injury as measured in terms of infarct size, loss of memory and motor coordination. RS 102895, a selective CCR-2 chemokine receptor antagonist, attenuated the neuroprotective effect of both the ischemic preconditioning as well as postconditioning. It is concluded that the neuroprotective effect of both ischemic preconditioning as well as ischemic postconditioning may involve the activation of CCR-2 chemokine receptors. Copyright © 2012 Elsevier Ltd. All rights reserved.

Free Radical Damage in Ischemia-Reperfusion Injury: An Obstacle in Acute Ischemic Stroke after Revascularization Therapy

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Ming-Shuo Sun

2018-01-01

Full Text Available Acute ischemic stroke is a common cause of morbidity and mortality worldwide. Thrombolysis with recombinant tissue plasminogen activator and endovascular thrombectomy are the main revascularization therapies for acute ischemic stroke. However, ischemia-reperfusion injury after revascularization therapy can result in worsening outcomes. Among all possible pathological mechanisms of ischemia-reperfusion injury, free radical damage (mainly oxidative/nitrosative stress injury has been found to play a key role in the process. Free radicals lead to protein dysfunction, DNA damage, and lipid peroxidation, resulting in cell death. Additionally, free radical damage has a strong connection with inducing hemorrhagic transformation and cerebral edema, which are the major complications of revascularization therapy, and mainly influencing neurological outcomes due to the disruption of the blood-brain barrier. In order to get a better clinical prognosis, more and more studies focus on the pharmaceutical and nonpharmaceutical neuroprotective therapies against free radical damage. This review discusses the pathological mechanisms of free radicals in ischemia-reperfusion injury and adjunctive neuroprotective therapies combined with revascularization therapy against free radical damage.

Neonatal ischemic brain injury: what every radiologist needs to know

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Badve, Chaitra A.; Khanna, Paritosh C.; Ishak, Gisele E.

2012-01-01

We present a pictorial review of neonatal ischemic brain injury and look at its pathophysiology, imaging features and differential diagnoses from a radiologist's perspective. The concept of perinatal stroke is defined and its distinction from hypoxic-ischemic injury is emphasized. A brief review of recent imaging advances is included and a diagnostic approach to neonatal ischemic brain injury is suggested. (orig.)

Neonatal ischemic brain injury: what every radiologist needs to know

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Badve, Chaitra A.; Khanna, Paritosh C.; Ishak, Gisele E. [Seattle Children' s Hospital, University of Washington Medical Center, Department of Radiology, Seattle, WA (United States)

2012-05-15

We present a pictorial review of neonatal ischemic brain injury and look at its pathophysiology, imaging features and differential diagnoses from a radiologist's perspective. The concept of perinatal stroke is defined and its distinction from hypoxic-ischemic injury is emphasized. A brief review of recent imaging advances is included and a diagnostic approach to neonatal ischemic brain injury is suggested. (orig.)

Drug Delivery to the Ischemic Brain

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Thompson, Brandon J.; Ronaldson, Patrick T.

2014-01-01

Cerebral ischemia occurs when blood flow to the brain is insufficient to meet metabolic demand. This can result from cerebral artery occlusion that interrupts blood flow, limits CNS supply of oxygen and glucose, and causes an infarction/ischemic stroke. Ischemia initiates a cascade of molecular events inneurons and cerebrovascular endothelial cells including energy depletion, dissipation of ion gradients, calcium overload, excitotoxicity, oxidative stress, and accumulation of ions and fluid. Blood-brain barrier (BBB) disruption is associated with cerebral ischemia and leads to vasogenic edema, a primary cause of stroke-associated mortality. To date, only a single drug has received US Food and Drug Administration (FDA) approval for acute ischemic stroke treatment, recombinant tissue plasminogen activator (rt-PA). While rt-PA therapy restores perfusion to ischemic brain, considerable tissue damage occurs when cerebral blood flow is re-established. Therefore, there is a critical need for novel therapeutic approaches that can “rescue” salvageable brain tissue and/or protect BBB integrity during ischemic stroke. One class of drugs that may enable neural cell rescue following cerebral ischemia/reperfusion injury is the HMG-CoA reductase inhibitors (i.e., statins). Understanding potential CNS drug delivery pathways for statins is critical to their utility in ischemic stroke. Here, we review molecular pathways associated with cerebral ischemia and novel approaches for delivering drugs to treat ischemic disease. Specifically, we discuss utility of endogenous BBB drug uptake transporters such as organic anion transporting polypeptides (OATPs/Oatps) and nanotechnology-based carriers for optimization of CNS drug delivery. Overall, this chapter highlights state-of-the-art technologies that may improve pharmacotherapy of cerebral ischemia. PMID:25307217

Curcumin Protects Neuron against Cerebral Ischemia-Induced Inflammation through Improving PPAR-Gamma Function

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Zun-Jing Liu

2013-01-01

Full Text Available Cerebral ischemia is the most common cerebrovascular disease worldwide. Recent studies have demonstrated that curcumin had beneficial effect to attenuate cerebral ischemic injury. However, it is unclear how curcumin protects against cerebral ischemic injury. In the present study, using rat middle cerebral artery occlusion model, we found that curcumin was a potent PPARγ agonist in that it upregulated PPARγ expression and PPARγ-PPRE binding activity. Administration of curcumin markedly decreased the infarct volume, improved neurological deficits, and reduced neuronal damage of rats. In addition, curcumin suppressed neuroinflammatory response by decreasing inflammatory mediators, such as IL-1β, TNF-α, PGE2, NO, COX-2, and iNOS induced by cerebral ischemia of rats. Furthermore, curcumin suppressed IκB degradation that was caused by cerebral ischemia. The present data also showed that PPARγ interacted with NF-κB-p65 and thus inhibited NF-κB activation. All the above protective effects of curcumin on cerebral ischemic injury were markedly attenuated by GW9662, an inhibitor of PPARγ. Our results as described above suggested that PPARγ induced by curcumin may play a critical role in protecting against brain injury through suppression of inflammatory response. It also highlights the potential of curcumin as a therapeutic agent against cerebral ischemia.

Relationship between hypertensive cerebral hemorrhage and ischemic lesions

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Yamaguchi, Shinya; Tsuchiya, Takashi; Yamaguchi, Takenori

1991-01-01

Patchy parenchymal lesions of increased intensity were frequently identified in patients with cerebral hemorrhage in T2-weighted image of high-fields MR imaging. We studied 64 patients with brain hemorrhage to determine the frequency and distribution of those lesions. We defined an area with high intensity in T2 weighted and low or iso-intensity area in T1 weighted images smaller than 1.5 cm in diameter to be 'ischemic lesion'. Ishemic lesions were found in 48 (75%) of all cases; in 25 (75%) of 32 patients with putaminal hemorrhage, in 15 (100%) of 15 with thalamic hemorrhage, in 3 (33%) of 9 with subcortical hemorrhage. Multiple ischemic lesions were more frequently seen in thalamic hemorrhage than in putaminal hemorrhage. Only 5 (10%) of 48 cases with associated ischemic lesions had a previous history related to those lesions. Multivariable regression analysis identified hypertension as the major predictor of the presence of ischemic lesions. Patients with brain hemorrhage frequently accompanied with incidental ischemic lesions, making it difficult to establish a guideline of blood pressure control for prevention of recurrent stroke. (author)

Cerebral Vascular Injury in Traumatic Brain Injury.

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Kenney, Kimbra; Amyot, Franck; Haber, Margalit; Pronger, Angela; Bogoslovsky, Tanya; Moore, Carol; Diaz-Arrastia, Ramon

2016-01-01

Traumatic cerebral vascular injury (TCVI) is a very frequent, if not universal, feature after traumatic brain injury (TBI). It is likely responsible, at least in part, for functional deficits and TBI-related chronic disability. Because there are multiple pharmacologic and non-pharmacologic therapies that promote vascular health, TCVI is an attractive target for therapeutic intervention after TBI. The cerebral microvasculature is a component of the neurovascular unit (NVU) coupling neuronal metabolism with local cerebral blood flow. The NVU participates in the pathogenesis of TBI, either directly from physical trauma or as part of the cascade of secondary injury that occurs after TBI. Pathologically, there is extensive cerebral microvascular injury in humans and experimental animal, identified with either conventional light microscopy or ultrastructural examination. It is seen in acute and chronic TBI, and even described in chronic traumatic encephalopathy (CTE). Non-invasive, physiologic measures of cerebral microvascular function show dysfunction after TBI in humans and experimental animal models of TBI. These include imaging sequences (MRI-ASL), Transcranial Doppler (TCD), and Near InfraRed Spectroscopy (NIRS). Understanding the pathophysiology of TCVI, a relatively under-studied component of TBI, has promise for the development of novel therapies for TBI. Published by Elsevier Inc.

Toll-like receptors in cerebral ischemic inflammatory injury

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Wang, Yan-Chun; Lin, Sen; Yang, Qing-Wu

2011-01-01

Abstract Cerebral ischemia triggers acute inflammation, which has been associated with an increase in brain damage. The mechanisms that regulate the inflammatory response after cerebral ischemia are multifaceted. An important component of this response is the activation of the innate immune system. However, details of the role of the innate immune system within the complex array of mechanisms in cerebral ischemia remain unclear. There have been recent great strides in our understanding of the...

Computerized tomographic evaluation of chronic ischemic lesions in cerebral white matter

International Nuclear Information System (INIS)

Yamanouchi, Hiroshi; Tohgi, Hideo; Iio, Masahiro; Tomonaga, Masanori.

1981-01-01

The purpose of this study is to clarify the correlation between the low density areas and periventricular lucency (PVL) on CT and the histopathologic changes of chronic ischemic lesions in cerebral white matter. Thirty seven brains from chronic cases with stroke and 17 brains from patients who showed PVLs on CT were examined histologically. CT scans were performed using GE CT/T. Chronic ischemic lesions with severe demyelination or diffuse cavitation were detected as low density areas on CT. But if associated with severe gliosis, those lesions could not be detected on CT. Areas with myelin pallor could not be detected on CT. In some cases diffuse ischemic lesions as demyelination and cavitation were found in the areas corresponding to PVLs on CT. However, they were not always expressed on CT. Other cases with PVL had no histological changes in the frontal white matter. In conclusion, chronic ischemic lesions in the cerebral white matter could not always be detected as low density areas on CT. This may be partly because decreased density due to demyelination and cavitation was counterbalanced by severe gliosis which tends to increase the density. In some cases PVLs were related to diffuse ischemic lesions in the frontal white matter, but this was not always the case. (author)

Intra-artery thrombolytic therapy for acute ischemic cerebral infarction

International Nuclear Information System (INIS)

Du Wei; Shao Chengmin; Wang Jianlin; Lei Jin; Jia Fan; Cao Lanfang; Chai Ruchang; Su Wei; Gu Jinchuan

2004-01-01

Objective: To evaluate the clinical effects of intra-arterial thrombolytic therapy for acute ischemic cerebral infarction and analyze the factors influencing the clinical prognosis. Methods: 32 patients were treated with intra-arterial thrombolysis using urokinase (median dose, 65 x 10 4 U) within 2-20 hours, after the onset. The patient's condition was assessed by neurologists using National Institutes of Health Stroke Scale (NIHSS) score right at the admission. Clinical outcome was assessed after 3 months and graded as good for Modified Rankin Scale (MRS) scores of 0 to 3 and poor for MRS scores of 4 or 5 and death. Results: Follow up cerebral angiography of 14 cases treated within 6 hours after onset showed complete/partial recanalization in 13 cases. Other 18 patients whose treatment started beyond 6 hours after onset out-came with complete/partial in 7. 20 (62.5%) of the 32 patients had good out-come, 12(37.5%) had poor outcome and two patients(9.4%) died. Cerebral hemorrhage occurred in 2 of the 32 patients. Good outcome was associated with an initial NIHSS score of <20 (P<0.01) and vascular recanalization (P<0.025). Recanalization was more likely to be obtained if thrombolysis began within 6 hours (P<0.05). Conclusion: Intra-arterial thrombolysis is a safe and effective therapy for acute ischemic cerebral infarction. (authors)

LXW7 ameliorates focal cerebral ischemia injury and attenuates inflammatory responses in activated microglia in rats

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Fang, T.; Zhou, D.; Lu, L.; Tong, X.; Wu, J.; Yi, L.

2016-01-01

Inflammation plays a pivotal role in ischemic stroke, when activated microglia release excessive pro-inflammatory mediators. The inhibition of integrin αvβ3 improves outcomes in rat focal cerebral ischemia models. However, the mechanisms by which microglia are neuroprotective remain unclear. This study evaluated whether post-ischemic treatment with another integrin αvβ3 inhibitor, the cyclic arginine-glycine-aspartic acid (RGD) peptide-cGRGDdvc (LXW7), alleviates cerebral ischemic injury. The anti-inflammatory effect of LXW7 in activated microglia within rat focal cerebral ischemia models was examined. A total of 108 Sprague-Dawley rats (250–280 g) were subjected to middle cerebral artery occlusion (MCAO). After 2 h, the rats were given an intravenous injection of LXW7 (100 μg/kg) or phosphate-buffered saline (PBS). Neurological scores, infarct volumes, brain water content (BWC) and histology alterations were determined. The expressions of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β)], and Iba1-positive activated microglia, within peri-ischemic brain tissue, were assessed with ELISA, western blot and immunofluorescence staining. Infarct volumes and BWC were significantly lower in LXW7-treated rats compared to those in the MCAO + PBS (control) group. The LXW7 treatment lowered the expression of pro-inflammatory cytokines. There was a reduction of Iba1-positive activated microglia, and the TNF-α and IL-1β expressions were attenuated. However, there was no difference in the Zea Longa scores between the ischemia and LXW7 groups. The results suggest that LXW7 protected against focal cerebral ischemia and attenuated inflammation in activated microglia. LXW7 may be neuroprotective during acute MCAO-induced brain damage and microglia-related neurodegenerative diseases

LXW7 ameliorates focal cerebral ischemia injury and attenuates inflammatory responses in activated microglia in rats

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Fang, T.; Zhou, D.; Lu, L.; Tong, X.; Wu, J.; Yi, L. [Department of Neurology, Shenzhen Hospital, Peking University, Shenzhen (China)

2016-08-01

Inflammation plays a pivotal role in ischemic stroke, when activated microglia release excessive pro-inflammatory mediators. The inhibition of integrin αvβ3 improves outcomes in rat focal cerebral ischemia models. However, the mechanisms by which microglia are neuroprotective remain unclear. This study evaluated whether post-ischemic treatment with another integrin αvβ3 inhibitor, the cyclic arginine-glycine-aspartic acid (RGD) peptide-cGRGDdvc (LXW7), alleviates cerebral ischemic injury. The anti-inflammatory effect of LXW7 in activated microglia within rat focal cerebral ischemia models was examined. A total of 108 Sprague-Dawley rats (250–280 g) were subjected to middle cerebral artery occlusion (MCAO). After 2 h, the rats were given an intravenous injection of LXW7 (100 μg/kg) or phosphate-buffered saline (PBS). Neurological scores, infarct volumes, brain water content (BWC) and histology alterations were determined. The expressions of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β)], and Iba1-positive activated microglia, within peri-ischemic brain tissue, were assessed with ELISA, western blot and immunofluorescence staining. Infarct volumes and BWC were significantly lower in LXW7-treated rats compared to those in the MCAO + PBS (control) group. The LXW7 treatment lowered the expression of pro-inflammatory cytokines. There was a reduction of Iba1-positive activated microglia, and the TNF-α and IL-1β expressions were attenuated. However, there was no difference in the Zea Longa scores between the ischemia and LXW7 groups. The results suggest that LXW7 protected against focal cerebral ischemia and attenuated inflammation in activated microglia. LXW7 may be neuroprotective during acute MCAO-induced brain damage and microglia-related neurodegenerative diseases.

Paradigms and mechanisms of inhalational anesthetics mediated neuroprotection against cerebral ischemic stroke.

Science.gov (United States)

Wang, Hailian; Li, Peiying; Xu, Na; Zhu, Ling; Cai, Mengfei; Yu, Weifeng; Gao, Yanqin

2016-01-01

Cerebral ischemic stroke is a leading cause of serious long-term disability and cognitive dysfunction. The high mortality and disability of cerebral ischemic stroke is urging the health providers, including anesthesiologists and other perioperative professioners, to seek effective protective strategies, which are extremely limited, especially for those perioperative patients. Intriguingly, several commonly used inhalational anesthetics are recently suggested to possess neuroprotective effects against cerebral ischemia. This review introduces multiple paradigms of inhalational anesthetic treatments that have been investigated in the setting of cerebral ischemia, such as preconditioning, proconditioning and postconditioning with a variety of inhalational anesthetics. The pleiotropic mechanisms underlying these inhalational anesthetics-afforded neuroprotection against stroke are also discussed in detail, including the common pathways shared by most of the inhalational anesthetic paradigms, such as anti-excitotoxicity, anti-apoptosis and anti-inflammation. There are also distinct mechanisms involved in specific paradigms, such as preserving blood brain barrier integrity, regulating cerebral blood flow and catecholamine release. The ready availability of these inhalational anesthetics bedside and renders them a potentially translatable stroke therapy attracting great efforts for understanding of the underlying mechanisms.

Retinal protective effects of topically administered agmatine on ischemic ocular injury caused by transient occlusion of the ophthalmic artery

Science.gov (United States)

Hong, S.; Hara, H.; Shimazawa, M.; Hyakkoku, K.; Kim, C.Y.; Seong, G.J.

2012-01-01

Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intraluminal occlusion of the middle cerebral artery of ddY mice (30-35 g) for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6), a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6), a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal sections were stained by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Transient ocular ischemia induced apoptosis of retinal cells in the entire retinal layer, and topically administered agmatine can significantly reduce this ischemic retinal injury. The proportion of apoptotic cells was definitely decreased (P agmatine application effectively decreases retinal damage in an in vivo ocular ischemic injury model. This implies that agmatine is a good candidate as a direct neuroprotective agent for eyes with ocular ischemic diseases. PMID:22331138

The protective effect of SCR(15-18) on cerebral ischemia-reperfusion injury.

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Li, Shu; Xian, Jinhong; He, Li; Luo, Xue; Tan, Bing; Yang, Yongtao; Liu, Gaoke; Wang, Zhengqing

2011-10-01

Soluble complement receptor type 1 (sCR1), a potent inhibitor of complement activation, has been shown to protect brain cells against cerebral ischemic/reperfusion (CI/R) injury due to its decay-accelerating activity for C3/C5 convertase and co-factor activity for C3b/C4b degradation. However, the effect of short consensus repeats (SCRs) 15-18, one of active domains of sCR1 with high C3b/C4b degradability, has not been demonstrated. Here, we investigated the protective effect of recombinant SCR(15-18) protein in middle cerebral artery occlusion (MCAO)-induced focal CI/R injury. Recombinant SCR(15-18) protein was successfully expressed in Escherichia coli and refolded to its optimal bioactivity. Seventy-five Sprague-Dawley rats were randomly assigned into three groups: sham-operated group, CI/R group, and SCR(15-18)+CI/R group pretreated with 20 mg/kg SCR(15-18) protein. After 2 hours of MCAO and subsequent 24 hours of reperfusion, rats were evaluated for neurological deficits and cerebral infarction. Polymorphonuclear leukocyte accumulation, C3b deposition, and morphological changes in cerebral tissue were also estimated. SCR(15-18) pretreatment induced a 20% reduction of infarct size and an improvement of neurological function with 22·2% decrease of neurological deficit scores. Inhibition of cerebral neutrophils infiltration by SCR(15-18) was indicated from the reduction of myeloperoxidase activity in SCR(15-18)+CI/R rats. Decreased C3b deposition and improved morphological changes were also found in cerebral tissue of SCR(15-18)-treated rats. Our studies suggest a definitive moderately protective effect of SCR(15-18) against CI/R damage and provide preclinical experimental evidence supporting the possibility of using it as a small anti-complement therapeutic agent for CI/R injury therapy.

Neuroprotective effect of hydroxy safflor yellow A against cerebral ischemia-reperfusion injury in rats: putative role of mPTP.

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Ramagiri, Sruthi; Taliyan, Rajeev

2016-01-01

Hydroxy safflor yellow A (HSYA) has been translated clinically for cardiovascular diseases. HSYA is also greatly acknowledged for its protective effects against cerebral ischemic-reperfusion (I/R) injury. Although the precise mechanism of cerebral I/R injury is not fully understood, oxygen-derived free radicals and mitochondrial permeability transition pore (mPTP) opening during I/R injury are widely recognized as an important contributor to neuronal injury. Thus, we speculated that the neuroprotective effects of HSYA against cerebral I/R injury may be associated with mPTP modulation. Induction of I/R injury was achieved by 60 min of middle cerebral artery occlusion, followed by reperfusion for 24 h. For behavior and cognitive assessment, neurological scoring (NSS), rotarod, and Y-maze task were performed. Oxidative damage was measured in terms of markers such as malondialdehyde, reduced glutathione, and catalase levels and cerebral infarct volumes were quantified using 2,3,5-triphenyl tetrazolinium chloride staining. I/R injury-induced inflammation was determined using tumor necrosis factor-α (TNF-α) levels. Animals exposed to I/R injury showed neurological severity, functional and cognitive disability, elevated oxidative markers, and TNF-α levels along with large infarct volumes. HSYA treatment during onset of reperfusion ameliorated performance in NSS, rotarod and Y-maze attenuated oxidative damage, TNF-α levels, and infarction rate. However, treatment with carboxyatractyloside, an mPTP opener, 20 min before HSYA, attenuated the protective effect of HSYA. Our study confirmed that protective effect of HSYA may be conferred through its free radical scavenger action followed by inhibiting the opening of mPTP during reperfusion and HSYA might act as a promising therapeutic agent against cerebral I/R injury.

Paeoniflorin, a Monoterpene Glycoside, Protects the Brain from Cerebral Ischemic Injury via Inhibition of Apoptosis.

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Zhang, Yuqin; Li, Huang; Huang, Mingqing; Huang, Mei; Chu, Kedan; Xu, Wei; Zhang, Shengnan; Que, Jinhua; Chen, Lidian

2015-01-01

Paeoniflorin (PF) is a principal bioactive component, which exhibits many pharmacological effects, including protection against ischemic injury. This paper aimed to investigate the protective effect of PF both in vivo and in vitro. Middle cerebral artery occlusion (MCAO) was performed on male Sprague-Dawley (SD) rat for 2 h, and different doses of PF or vehicle were administered 2 h after reperfusion. Rats were sacrificed after 7 days treatment of PF/vehicle. PF treatment for 7 days ameliorated MCAO-induced neurological deficit and decreased the infarct area. Further study demonstrated that PF inhibited the over-activation of astrocytes and apoptosis of neurons, and PF promoted up-regulation of neuronal specific marker neuron-specific nuclear (NeuN) and microtubule-associated protein 2 (MAP-2) in brain. Moreover, NMDA-induced neuron apoptosis was employed. The in vitro study revealed that PF treatment protected against NMDA-induced cell apoptosis and neuronal loss via up-regulation of neuronal specific marker NeuN, MAP-2 and Bcl-2 and the down-regulation Bax. Taken together, the present study demonstrates that PF produces its protective effect by inhibiting the over-activation of astrocytes, apoptosis of neurons and up-regulation of neuronal specific marker NeuN, MAP-2, and B-cell lymphoma-2 (Bcl-2), and down-regulation Bax. Our study reveals that PF may be a potential neuroprotective agent for stroke and can provide basic data for clinical use.

Protective effect of tetraethyl pyrazine against focal cerebral ischemia/reperfusion injury in rats: therapeutic time window and its mechanism.

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Jia, Jie; Zhang, Xi; Hu, Yong-Shan; Wu, Yi; Wang, Qing-Zhi; Li, Na-Na; Wu, Cai-Qin; Yu, Hui-Xian; Guo, Qing-Chuan

2009-03-01

Tetramethyl pyrazine has been considered an effective agent in treating neurons ischemia/reperfusion injury, but the mechanism of its therapeutic effect remains unclear. This study was to explore the therapeutic time window and mechanism of tetramethyl pyrazine on temporary focal cerebral ischemia/reperfusion injury. Middle cerebral artery occlusion was conducted in male Sprague-Dawley rats and 20 mg/kg of tetramethyl pyrazine was intraperitoneally injected at different time points. At 72 h after reperfusion, all animals' neurologic deficit scores were evaluated. Cerebrums were removed and cerebral infarction volume was measured. The expression of thioredoxin and thioredoxin reductase mRNA was determined at 6 and 24 h after reperfusion. Cerebral infarction volume and neurological deficit scores were significantly decreased in the group with tetramethyl pyrazine treatment. The expression of thioredoxin-1/thioredoxin-2 and thioredoxin reductase-1/thioredoxin reductase-2 was significantly decreased in rats with ischemia/reperfusion injury, while it was increased by tetramethyl pyrazine administration. Treatment with tetramethyl pyrazine, within 4 h after reperfusion, protects the brain from ischemic reperfusion injury in rats. The neuroprotective mechanism of tetramethyl pyrazine treatment is, in part, mediated through the upregulation of thioredoxin transcription.

Intranasal Delivery of Granulocyte Colony-Stimulating Factor Enhances Its Neuroprotective Effects Against Ischemic Brain Injury in Rats.

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Sun, Bao-Liang; He, Mei-Qing; Han, Xiang-Yu; Sun, Jing-Yi; Yang, Ming-Feng; Yuan, Hui; Fan, Cun-Dong; Zhang, Shuai; Mao, Lei-Lei; Li, Da-Wei; Zhang, Zong-Yong; Zheng, Cheng-Bi; Yang, Xiao-Yi; Li, Yang V; Stetler, R Anne; Chen, Jun; Zhang, Feng

2016-01-01

Granulocyte colony-stimulating factor (G-CSF) is a hematopoietic growth factor with strong neuroprotective properties. However, it has limited capacity to cross the blood-brain barrier and thus potentially limiting its protective capacity. Recent studies demonstrated that intranasal drug administration is a promising way in delivering neuroprotective agents to the central nervous system. The current study therefore aimed at determining whether intranasal administration of G-CSF increases its delivery to the brain and its neuroprotective effect against ischemic brain injury. Transient focal cerebral ischemia in rat was induced with middle cerebral artery occlusion. Our resulted showed that intranasal administration is 8-12 times more effective than subcutaneous injection in delivering G-CSF to cerebrospinal fluid and brain parenchyma. Intranasal delivery enhanced the protective effects of G-CSF against ischemic injury in rats, indicated by decreased infarct volume and increased recovery of neurological function. The neuroprotective mechanisms of G-CSF involved enhanced upregulation of HO-1 and reduced calcium overload following ischemia. Intranasal G-CSF application also promoted angiogenesis and neurogenesis following brain ischemia. Taken together, G-CSF is a legitimate neuroprotective agent and intranasal administration of G-CSF is more effective in delivery and neuroprotection and could be a practical approach in clinic.

Paradigms and mechanisms of inhalational anesthetics mediated neuroprotection against cerebral ischemic stroke

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Hailian Wang

2016-01-01

Full Text Available Cerebral ischemic stroke is a leading cause of serious long-term disability and cognitive dysfunction. The high mortality and disability of cerebral ischemic stroke is urging the health providers, including anesthesiologists and other perioperative professioners, to seek effective protective strategies, which are extremely limited, especially for those perioperative patients. Intriguingly, several commonly used inhalational anesthetics are recently suggested to possess neuroprotective effects against cerebral ischemia. This review introduces multiple paradigms of inhalational anesthetic treatments that have been investigated in the setting of cerebral ischemia, such as preconditioning, proconditioning and postconditioning with a variety of inhalational anesthetics. The pleiotropic mechanisms underlying these inhalational anesthetics-afforded neuroprotection against stroke are also discussed in detail, including the common pathways shared by most of the inhalational anesthetic paradigms, such as anti-excitotoxicity, anti-apoptosis and anti-inflammation. There are also distinct mechanisms involved in specific paradigms, such as preserving blood brain barrier integrity, regulating cerebral blood flow and catecholamine release. The ready availability of these inhalational anesthetics bedside and renders them a potentially translatable stroke therapy attracting great efforts for understanding of the underlying mechanisms.

Splenectomy exacerbates lung injury after ischemic acute kidney injury in mice

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Andrés-Hernando, Ana; Altmann, Christopher; Ahuja, Nilesh; Lanaspa, Miguel A.; Nemenoff, Raphael; He, Zhibin; Ishimoto, Takuji; Simpson, Pete A.; Weiser-Evans, Mary C.; Bacalja, Jasna

2011-01-01

Patients with acute kidney injury (AKI) have increased serum proinflammatory cytokines and an increased occurrence of respiratory complications. The aim of the present study was to examine the effect of renal and extrarenal cytokine production on AKI-mediated lung injury in mice. C57Bl/6 mice underwent sham surgery, splenectomy, ischemic AKI, or ischemic AKI with splenectomy and kidney, spleen, and liver cytokine mRNA, serum cytokines, and lung injury were examined. The proinflammatory cytokines IL-6, CXCL1, IL-1β, and TNF-α were increased in the kidney, spleen, and liver within 6 h of ischemic AKI. Since splenic proinflammatory cytokines were increased, we hypothesized that splenectomy would protect against AKI-mediated lung injury. On the contrary, splenectomy with AKI resulted in increased serum IL-6 and worse lung injury as judged by increased lung capillary leak, higher lung myeloperoxidase activity, and higher lung CXCL1 vs. AKI alone. Splenectomy itself was not associated with increased serum IL-6 or lung injury vs. sham. To investigate the mechanism of the increased proinflammatory response, splenic production of the anti-inflammatory cytokine IL-10 was determined and was markedly upregulated. To confirm that splenic IL-10 downregulates the proinflammatory response of AKI, IL-10 was administered to splenectomized mice with AKI, which reduced serum IL-6 and improved lung injury. Our data demonstrate that AKI in the absence of a counter anti-inflammatory response by splenic IL-10 production results in an exuberant proinflammatory response and lung injury. PMID:21677145

Neuroprotective effect of pretreatment with ganoderma lucidum in cerebral ischemia/reperfusion injury in rat hippocampus

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Zhang, Wangxin; Zhang, Quiling; Deng, Wen; Li, Yalu; Xing, Guoqing; Shi, Xinjun; Du, Yifeng

2014-01-01

Ganoderma lucidum is a traditional Chinese medicine, which has been shown to have both anti-oxidative and anti-inflammatory effects, and noticeably decreases both the infarct area and neuronal apoptosis of the ischemic cortex. This study aimed to investigate the protective effects and mechanisms of pretreatment with ganoderma lucidum (by intragastric administration) in cerebral ischemia/reperfusion injury in rats. Our results showed that pretreatment with ganoderma lucidum for 3 and 7 days reduced neuronal loss in the hippocampus, diminished the content of malondialdehyde in the hippocampus and serum, decreased the levels of tumor necrosis factor-α and interleukin-8 in the hippocampus, and increased the activity of superoxide dismutase in the hippocampus and serum. These results suggest that pretreatment with ganoderma lucidum was protective against cerebral ischemia/reperfusion injury through its anti-oxidative and anti-inflammatory actions. PMID:25317156

Cerebral ischemia is exacerbated by extracellular nicotinamide phosphoribosyltransferase via a non-enzymatic mechanism.

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Bing Zhao

Full Text Available Intracellular nicotinamide phosphoribosyltransferase (iNAMPT in neuron has been known as a protective factor against cerebral ischemia through its enzymatic activity, but the role of central extracellular NAMPT (eNAMPT is not clear. Here we show that eNAMPT protein level was elevated in the ischemic rat brain after middle-cerebral-artery occlusion (MCAO and reperfusion, which can be traced to at least in part from blood circulation. Administration of recombinant NAMPT protein exacerbated MCAO-induced neuronal injury in rat brain, while exacerbated oxygen-glucose-deprivation (OGD induced neuronal injury only in neuron-glial mixed culture, but not in neuron culture. In the mixed culture, NAMPT protein promoted TNF-α release in a time- and concentration-dependent fashion, while TNF-α neutralizing antibody protected OGD-induced, NAMPT-enhanced neuronal injury. Importantly, H247A mutant of NAMPT with essentially no enzymatic activity exerted similar effects on ischemic neuronal injury and TNF-α release as the wild type protein. Thus, eNAMPT is an injurious and inflammatory factor in cerebral ischemia and aggravates ischemic neuronal injury by triggering TNF-α release from glia cells, via a mechanism not related to NAMPT enzymatic activity.

Retinal protective effects of topically administered agmatine on ischemic ocular injury caused by transient occlusion of the ophthalmic artery

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S. Hong

2012-03-01

Full Text Available Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intraluminal occlusion of the middle cerebral artery of ddY mice (30-35 g for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6, a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6, a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal sections were stained by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL. Transient ocular ischemia induced apoptosis of retinal cells in the entire retinal layer, and topically administered agmatine can significantly reduce this ischemic retinal injury. The proportion of apoptotic cells was definitely decreased (P < 0.001; Kruskal-Wallis test. Overall, we determined that topical agmatine application effectively decreases retinal damage in an in vivo ocular ischemic injury model. This implies that agmatine is a good candidate as a direct neuroprotective agent for eyes with ocular ischemic diseases.

Aging causes collateral rarefaction and increased severity of ischemic injury in multiple tissues

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Faber, James E.; Zhang, Hua; Lassance-Soares, Roberta M.; Prabhakar, Pranay; Najafi, Amir H.; Burnett, Mary Susan; Epstein, Stephen E.

2011-01-01

Objective Aging is a major risk factor for increased ischemic tissue injury. Whether collateral rarefaction and impaired remodeling contribute to this is unknown. We quantified the number and diameter of native collaterals, and their remodeling in 3-, 16-, 24-, and 31-months-old mice. Methods and Results Aging caused an “age-dose-dependent” greater drop in perfusion immediately after femoral artery ligation, followed by a diminished recovery of flow and increase in tissue injury. These effects were associated with a decline in collateral number, diameter and remodeling. Angiogenesis was also impaired. Mechanistically, these changes were not accompanied by reduced recruitment of T-cells or macrophages to remodeling collaterals. However, eNOS signaling was dysfunctional, as indicated by increased protein nitrosylation and less phosphorylated eNOS and VASP in collateral wall cells. The cerebral circulation exhibited a similar age-dose-dependent loss of collateral number and diameter and increased tortuosity, resulting in an increase in collateral resistance and infarct volume (e.g., 6- and 3-fold, respectively, in 24-months-old mice) after artery occlusion. This was not associated with rarefaction of similarly-sized arterioles. Collateral remodeling was also reduced. Conclusions Our findings demonstrate that aging causes rarefaction and insufficiency of the collateral circulation in multiple tissues, resulting in more severe ischemic tissue injury. PMID:21617137

Investigation of the role of non-selective calcium channel blocker (flunarizine) on cerebral ischemic-reperfusion associated cognitive dysfunction in aged mice.

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Gulati, Puja; Muthuraman, Arunachalam; Kaur, Parneet

2015-04-01

The present study was designed to investigate the role of flunarizine (a non-selective calcium channel blocker) on cerebral ischemic-reperfusion associated cognitive dysfunction in aged mice. Bilateral carotid artery occlusion of 12min followed by reperfusion for 24h was given to induce cerebral injury in male Swiss mice. The assessment of learning & memory was performed by Morris water maze test; motor in-coordination was evaluated by rota rod, lateral push and inclined beam walking tests; cerebral infarct size was quantified by triphenyltetrazolium chloride staining. In addition, reduced glutathione (GSH), total calcium and acetylcholinesterase (AChE) activity were also estimated in aged brain tissue. Donepezil treated group served as a positive control in this study. Ischemia reperfusion (I/R) injury produced significant increase in cerebral infarct size. A significant loss of memory along with impairment of motor performance was also noted. Further, I/R injury also produced significant increase in levels of total calcium, AChE activity and decrease in GSH levels. Pretreatment of flunarizine significantly attenuated I/R induced infarct size, behavioral and biochemical changes. Hence, it may be concluded that, a non-selective calcium channel blocker can be useful in I/R associated cognitive dysfunction due to its anti-oxidant, anti-infarct and modulatory actions of neurotransmitters & calcium channels. Copyright © 2015 Elsevier Inc. All rights reserved.

The Effects of Different Repetitive Transcranial Magnetic Stimulation (rTMS Protocols on Cortical Gene Expression in a Rat Model of Cerebral Ischemic-Reperfusion Injury.

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Milos R Ljubisavljevic

Full Text Available Although repetitive Transcranial Magnetic Stimulation (rTMS in treatment of stroke in humans has been explored over the past decade the data remain controversial in terms of optimal stimulation parameters and the mechanisms of rTMS long-term effects. This study aimed to explore the potential of different rTMS protocols to induce changes in gene expression in rat cortices after acute ischemic-reperfusion brain injury. The stroke was induced by middle cerebral artery occlusion (MCAO with subsequent reperfusion. Changes in the expression of 96 genes were examined using low-density expression arrays after MCAO alone and after MCAO combined with 1Hz, 5Hz, continuous (cTBS and intermittent (iTBS theta-burst rTMS. rTMS over the lesioned hemisphere was given for two weeks (with a 2-day pause in a single daily session and a total of 2400 pulses. MCAO alone induced significant upregulation in the expression of 44 genes and downregulation in 10. Two weeks of iTBS induced significant increase in the expression of 52 genes. There were no downregulated genes. 1Hz and 5Hz had no significant effects on gene expression, while cTBS effects were negligible. Upregulated genes included those involved in angiogenesis, inflammation, injury response and cellular repair, structural remodeling, neuroprotection, neurotransmission and neuronal plasticity. The results show that long-term rTMS in acute ischemic-reperfusion brain injury induces complex changes in gene expression that span multiple pathways, which generally promote the recovery. They also demonstrate that induced changes primarily depend on the rTMS frequency (1Hz and 5Hz vs. iTBS and pattern (cTBS vs. iTBS. The results further underlines the premise that one of the benefits of rTMS application in stroke may be to prime the brain, enhancing its potential to cope with the injury and to rewire. This could further augment its potential to favorably respond to rehabilitation, and to restore some of the loss

The Effects of Different Repetitive Transcranial Magnetic Stimulation (rTMS) Protocols on Cortical Gene Expression in a Rat Model of Cerebral Ischemic-Reperfusion Injury

Science.gov (United States)

Ljubisavljevic, Milos R.; Javid, Asma; Oommen, Joji; Parekh, Khatija; Nagelkerke, Nico; Shehab, Safa; Adrian, Thomas E.

2015-01-01

Although repetitive Transcranial Magnetic Stimulation (rTMS) in treatment of stroke in humans has been explored over the past decade the data remain controversial in terms of optimal stimulation parameters and the mechanisms of rTMS long-term effects. This study aimed to explore the potential of different rTMS protocols to induce changes in gene expression in rat cortices after acute ischemic-reperfusion brain injury. The stroke was induced by middle cerebral artery occlusion (MCAO) with subsequent reperfusion. Changes in the expression of 96 genes were examined using low-density expression arrays after MCAO alone and after MCAO combined with 1Hz, 5Hz, continuous (cTBS) and intermittent (iTBS) theta-burst rTMS. rTMS over the lesioned hemisphere was given for two weeks (with a 2-day pause) in a single daily session and a total of 2400 pulses. MCAO alone induced significant upregulation in the expression of 44 genes and downregulation in 10. Two weeks of iTBS induced significant increase in the expression of 52 genes. There were no downregulated genes. 1Hz and 5Hz had no significant effects on gene expression, while cTBS effects were negligible. Upregulated genes included those involved in angiogenesis, inflammation, injury response and cellular repair, structural remodeling, neuroprotection, neurotransmission and neuronal plasticity. The results show that long-term rTMS in acute ischemic-reperfusion brain injury induces complex changes in gene expression that span multiple pathways, which generally promote the recovery. They also demonstrate that induced changes primarily depend on the rTMS frequency (1Hz and 5Hz vs. iTBS) and pattern (cTBS vs. iTBS). The results further underlines the premise that one of the benefits of rTMS application in stroke may be to prime the brain, enhancing its potential to cope with the injury and to rewire. This could further augment its potential to favorably respond to rehabilitation, and to restore some of the loss functions. PMID

Detection and monitoring of cerebral hemodynamic disturbances with transcranial color-coded duplex sonography in patients after head injury

International Nuclear Information System (INIS)

Kochanowicz, J.; Mariak, Z.; Lyson, T.; Lewko, J.; Krejza, J.; Bilello, M.

2006-01-01

Reduced cerebral blood flow after severe head injury results in an increased risk of ischemic brain damage. Blood flow should therefore be monitored with a simple, reliable method. Transcranial color-coded Doppler sonography (TCCS) is an accepted tool for the diagnosis of cerebral vasospasm; however, its usefulness in evaluating patients with head injury has not been proven. Cerebral blood-flow velocity in the middle, anterior, and posterior cerebral arteries was measured with a 2.5 MHz probe (Aplio SSA 770A, Toshiba, Japan) in 36 subjects with moderate or severe head injury. Serial measurements of resistance index (RI), peak-systolic, end-diastolic, and mean velocity in the middle cerebral arteries were performed 2-24 h after head trauma and in the subsequent days during hospitalization. Immediately after head trauma, increased RI values, and unusually decreased blood-flow velocity (mainly in MCA) were observed. Microcirculation disturbances were suspected because the end-diastolic velocity had substantially diminished. Changes in blood-flow parameters correlated with the clinical state, and in most cases, a poor prognosis. In some patients, blood-flow velocity increased above the normal reference limit and this implied poor prognosis. Transcranial color-coded Doppler sonography is a reliable, repeatable, and accessible tool that provides information about cerebral blood-flow disturbances and may hold diagnostic and prognostic importance. (orig.)

Correlation between brain injury and dysphagia in adult patients with stroke

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Nunes, Maria Cristina de Alencar

2012-01-01

Full Text Available Introduction: In the literature, the incidence of oropharyngeal dysphagia in patients with cerebrovascular accident (AVE ranges 20-90%. Some studies correlate the location of a stroke with dysphagia, while others do not. Objective: To correlate brain injury with dysphagia in patients with stroke in relation to the type and location of stroke. Method: A prospective study conducted at the Hospital de Clinicas with 30 stroke patients: 18 women and 12 men. All patients underwent clinical evaluation and swallowing nasolaryngofibroscopy (FEES®, and were divided based on the location of the injury: cerebral cortex, cerebellar cortex, subcortical areas, and type: hemorrhagic or transient ischemic. Results: Of the 30 patients, 18 had ischemic stroke, 10 had hemorrhagic stroke, and 2 had transient stroke. Regarding the location, 10 lesions were in the cerebral cortex, 3 were in the cerebral and cerebellar cortices, 3 were in the cerebral cortex and subcortical areas, and 3 were in the cerebral and cerebellar cortices and subcortical areas. Cerebral cortex and subcortical area ischemic strokes predominated in the clinical evaluation of dysphagia. In FEES®, decreased laryngeal sensitivity persisted following cerebral cortex and ischemic strokes. Waste in the pharyngeal recesses associated with epiglottic valleculae predominated in the piriform cortex in all lesion areas and in ischemic stroke. A patient with damage to the cerebral and cerebellar cortices from an ischemic stroke exhibited laryngeal penetration and tracheal aspiration of liquid and honey. Conclusion: Dysphagia was prevalent when a lesion was located in the cerebral cortex and was of the ischemic type.

Pretreatment with Sodium Phenylbutyrate Alleviates Cerebral Ischemia/Reperfusion Injury by Upregulating DJ-1 Protein

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Rui-Xin Yang

2017-06-01

Full Text Available Oxidative stress and mitochondrial dysfunction play critical roles in ischemia/reperfusion (I/R injury. DJ-1 is an endogenous antioxidant that attenuates oxidative stress and maintains mitochondrial function, likely acting as a protector of I/R injury. In the present study, we explored the protective effect of a possible DJ-1 agonist, sodium phenylbutyrate (SPB, against I/R injury by protecting mitochondrial dysfunction via the upregulation of DJ-1 protein. Pretreatment with SPB upregulated the DJ-1 protein level and rescued the I/R injury-induced DJ-1 decrease about 50% both in vivo and in vitro. SPB also improved cellular viability and mitochondrial function and alleviated neuronal apoptosis both in cell and animal models; these effects of SPB were abolished by DJ-1 knockdown with siRNA. Furthermore, SPB improved the survival rate about 20% and neurological functions, as well as reduced about 50% of the infarct volume and brain edema, of middle cerebral artery occlusion mice 23 h after reperfusion. Therefore, our findings demonstrate that preconditioning of SPB possesses a neuroprotective effect against cerebral I/R injury by protecting mitochondrial function dependent on the DJ-1 upregulation, suggesting that DJ-1 is a potential therapeutic target for clinical ischemic stroke.

Pretreatment with Sodium Phenylbutyrate Alleviates Cerebral Ischemia/Reperfusion Injury by Upregulating DJ-1 Protein.

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Yang, Rui-Xin; Lei, Jie; Wang, Bo-Dong; Feng, Da-Yun; Huang, Lu; Li, Yu-Qian; Li, Tao; Zhu, Gang; Li, Chen; Lu, Fang-Fang; Nie, Tie-Jian; Gao, Guo-Dong; Gao, Li

2017-01-01

Oxidative stress and mitochondrial dysfunction play critical roles in ischemia/reperfusion (I/R) injury. DJ-1 is an endogenous antioxidant that attenuates oxidative stress and maintains mitochondrial function, likely acting as a protector of I/R injury. In the present study, we explored the protective effect of a possible DJ-1 agonist, sodium phenylbutyrate (SPB), against I/R injury by protecting mitochondrial dysfunction via the upregulation of DJ-1 protein. Pretreatment with SPB upregulated the DJ-1 protein level and rescued the I/R injury-induced DJ-1 decrease about 50% both in vivo and in vitro . SPB also improved cellular viability and mitochondrial function and alleviated neuronal apoptosis both in cell and animal models; these effects of SPB were abolished by DJ-1 knockdown with siRNA. Furthermore, SPB improved the survival rate about 20% and neurological functions, as well as reduced about 50% of the infarct volume and brain edema, of middle cerebral artery occlusion mice 23 h after reperfusion. Therefore, our findings demonstrate that preconditioning of SPB possesses a neuroprotective effect against cerebral I/R injury by protecting mitochondrial function dependent on the DJ-1 upregulation, suggesting that DJ-1 is a potential therapeutic target for clinical ischemic stroke.

Cerebral Microbleeds and the Risk of Incident Ischemic Stroke in CADASIL (Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy).

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Puy, Laurent; De Guio, François; Godin, Ophélia; Duering, Marco; Dichgans, Martin; Chabriat, Hugues; Jouvent, Eric

2017-10-01

Cerebral microbleeds are associated with an increased risk of intracerebral hemorrhage. Recent data suggest that microbleeds may also predict the risk of incident ischemic stroke. However, these results were observed in elderly individuals undertaking various medications and for whom causes of microbleeds and ischemic stroke may differ. We aimed to test the relationship between the presence of microbleeds and incident stroke in CADASIL (Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts and Leukoencephalopathy)-a severe monogenic small vessel disease known to be responsible for both highly prevalent microbleeds and a high incidence of ischemic stroke in young patients. We assessed microbleeds on baseline MRI in all 378 patients from the Paris-Munich cohort study. Incident ischemic strokes were recorded during 54 months. Survival analyses were used to test the relationship between microbleeds and incident ischemic stroke. Three hundred sixty-nine patients (mean age, 51.4±11.4 years) were followed-up during a median time of 39 months (interquartile range, 19 months). The risk of incident ischemic stroke was higher in patients with microbleeds than in patients without (35.8% versus 19.6%, hazard ratio, 1.87; 95% confidence interval, 1.16-3.01; P =0.009). These results persisted after adjustment for history of ischemic stroke, age, sex, vascular risk factors, and antiplatelet agents use (hazard ratio, 1.89; 95% confidence interval, 1.10-3.26; P =0.02). The presence of microbleeds is an independent risk marker of incident ischemic stroke in CADASIL, emphasizing the need to carefully interpret MRI data. © 2017 American Heart Association, Inc.

Dietary and plant polyphenols exert neuroprotective effects and improve cognitive function in cerebral ischemia.

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Panickar, Kiran S; Jang, Saebyeol

2013-08-01

Cerebral ischemia is caused by an interruption of blood flow to the brain which generally leads to irreversible brain damage. Ischemic injury is associated with vascular leakage, inflammation, tissue injury, and cell death. Cellular changes associated with ischemia include impairment of metabolism, energy failure, free radical production, excitotoxicity, altered calcium homeostasis, and activation of proteases all of which affect brain functioning and also contribute to longterm disabilities including cognitive decline. Inflammation, mitochondrial dysfunction, increased oxidative/nitrosative stress, and intracellular calcium overload contribute to brain injury including cell death and brain edema. However, there is a paucity of agents that can effectively reduce cerebral damage and hence considerable attention has focused on developing newer agents with more efficacy and fewer side-effects. Polyphenols are natural compounds with variable phenolic structures and are rich in vegetables, fruits, grains, bark, roots, tea, and wine. Most polyphenols have antioxidant, anti-inflammatory, and anti-apoptotic properties and their protective effects on mitochondrial functioning, glutamate uptake, and regulating intracellular calcium levels in ischemic injury in vitro have been demonstrated. This review will assess the current status of the potential effects of polyphenols in reducing cerebral injury and improving cognitive function in ischemia in animal and human studies. In addition, the review will also examine available patents in nutrition and agriculture that relates to cerebral ischemic injury with an emphasis on plant polyphenols.

Intermittent fasting attenuates inflammasome activity in ischemic stroke.

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Fann, David Yang-Wei; Santro, Tomislav; Manzanero, Silvia; Widiapradja, Alexander; Cheng, Yi-Lin; Lee, Seung-Yoon; Chunduri, Prasad; Jo, Dong-Gyu; Stranahan, Alexis M; Mattson, Mark P; Arumugam, Thiruma V

2014-07-01

Recent findings have revealed a novel inflammatory mechanism that contributes to tissue injury in cerebral ischemia mediated by multi-protein complexes termed inflammasomes. Intermittent fasting (IF) can decrease the levels of pro-inflammatory cytokines in the periphery and brain. Here we investigated the impact of IF (16h of food deprivation daily) for 4months on NLRP1 and NLRP3 inflammasome activities following cerebral ischemia. Ischemic stroke was induced in C57BL/6J mice by middle cerebral artery occlusion, followed by reperfusion (I/R). IF decreased the activation of NF-κB and MAPK signaling pathways, the expression of NLRP1 and NLRP3 inflammasome proteins, and both IL-1β and IL-18 in the ischemic brain tissue. These findings demonstrate that IF can attenuate the inflammatory response and tissue damage following ischemic stroke by a mechanism involving suppression of NLRP1 and NLRP3 inflammasome activity. Copyright © 2014 Elsevier Inc. All rights reserved.

Computerized tomography of the brain and associated risk factors in 240 patients iwth reversible cerebral ischemic attacks (RIAs)

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Bozzao, L.; Fantozzi, L.M.; Carolei, A.; Pappata, S.; Vesentini, G.; Allori, L.; Rasura, M.; Fieschi, C.

1985-01-01

The frequency and distribution of focal low density cerebral ischemic lesions in RIA patients with regard to factors as age at onset, number and temporal profile of the reversible cerebral ischemic events on admission, presence of associated medical conditions such as hypertension and diabetes mellitus, have been investigated with computerized tomography of the brain. (author). 7 refs.; 1 tab

Cerebral collateral therapeutics in acute ischemic stroke: A randomized preclinical trial of four modulation strategies.

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Beretta, Simone; Versace, Alessandro; Carone, Davide; Riva, Matteo; Dell'Era, Valentina; Cuccione, Elisa; Cai, Ruiyao; Monza, Laura; Pirovano, Silvia; Padovano, Giada; Stiro, Fabio; Presotto, Luca; Paternò, Giovanni; Rossi, Emanuela; Giussani, Carlo; Sganzerla, Erik P; Ferrarese, Carlo

2017-10-01

Cerebral collaterals are dynamically recruited after arterial occlusion and highly affect tissue outcome in acute ischemic stroke. We investigated the efficacy and safety of four pathophysiologically distinct strategies for acute modulation of collateral flow (collateral therapeutics) in the rat stroke model of transient middle cerebral artery (MCA) occlusion. A composed randomization design was used to assign rats (n = 118) to receive phenylephrine (induced hypertension), polygeline (intravascular volume load), acetazolamide (cerebral arteriolar vasodilation), head down tilt (HDT) 15° (cerebral blood flow diversion), or no treatment, starting 30 min after MCA occlusion. Compared to untreated animals, treatment with collateral therapeutics was associated with lower infarct volumes (62% relative mean difference; 51.57 mm 3 absolute mean difference; p Collateral therapeutics acutely increased cerebral perfusion in the medial (+40.8%; p collaterals is feasible and provides a tissue-saving effect in the hyperacute phase of ischemic stroke prior to recanalization therapy.

Cerebral hypoxia and ischemia in preterm infants

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Alberto Ravarino

2014-06-01

Full Text Available Premature birth is a major public health issue internationally affecting 13 million babies worldwide. Hypoxia and ischemia is probably the commonest type of acquired brain damage in preterm infants. The clinical manifestations of hypoxic-ischemic injury in survivors of premature birth include a spectrum of cerebral palsy and intellectual disabilities. Until recently, the extensive brain abnormalities in preterm neonates appeared to be related mostly to destructive processes that lead to substantial deletion of neurons, axons, and glia from necrotic lesions in the developing brain. Advances in neonatal care coincide with a growing body of evidence that the preterm gray and white matter frequently sustain less severe insults, where tissue destruction is the minor component. Periventricular leukomalacia (PVL is the major form of white matter injury and consists classically of focal necrotic lesions, with subsequent cyst formation, and a less severe but more diffuse injury to cerebral white mater, with prominent astrogliosis and microgliosis but without overt necrosis. With PVL a concomitant injury occurs to subplate neurons, located in the subcortical white matter. Severe hypoxic-ischemic insults that trigger significant white matter necrosis are accompanied by neuronal degeneration in cerebral gray and white matter. This review aims to illustrate signs of cerebral embryology of the second half of fetal life and correlate hypoxic-ischemic brain injury in the premature infant. This should help us better understand the symptoms early and late and facilitate new therapeutic strategies. Proceedings of the International Course on Perinatal Pathology (part of the 10th International Workshop on Neonatology · October 22nd-25th, 2014 · Cagliari (Italy · October 25th, 2014 · The role of the clinical pathological dialogue in problem solving Guest Editors: Gavino Faa, Vassilios Fanos, Peter Van Eyken

Sequential changes in ischemic edema following transient focal cerebral ischemia in rats; Magnetic resonance imaging study

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Nagahiro, Shinji; Goto, Satoshi; Kogo, Kasei; Sumi, Minako; Takahashi, Mutsumasa; Ushio, Yukitaka [Kumamoto Univ. (Japan). School of Medicine

1994-07-01

Sequential and regional changes in ischemic edema following various durations of focal cerebral ischemia were studied by magnetic resonance (MR) imaging in a rat unilateral intraluminal middle cerebral artery occlusion model. Occlusion was performed from 5 minutes to 5 hours. T[sub 2]-weighted images were obtained chronologically 6 hours after onset of ischemia, on day 1 and day 7. An immunohistochemical study using antibodies to calcineurin and glial fibrillary acidic protein was performed to observe histological changes in the ischemic brain. The T[sub 2] high-signal-intensity areas representing ischemic edema were observed in the lateral striatum and/or the cerebral cortex by day 1 in all rats with 1- to 5-hour ischemia, and the areas were larger and detected earlier with longer durations of ischemia. In three of six rats with 15-minute ischemia and five of six rats with 30-minute ischemia, the T[sub 2] high-signal-intensity areas appeared transiently on day 1 in the dorsolateral striatum where loss of neurons expressing calcineurin immunoreactivity and associated gliosis were found. MR imaging in animal models of reversible focal ischemia can achieve sequential and noninvasive evaluation of dynamic regional changes in ischemic edema. (author).

Seizure Severity Is Correlated With Severity of Hypoxic-Ischemic Injury in Abusive Head Trauma.

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Dingman, Andra L; Stence, Nicholas V; O'Neill, Brent R; Sillau, Stefan H; Chapman, Kevin E

2017-12-12

The objective of this study was to characterize hypoxic-ischemic injury and seizures in abusive head trauma. We performed a retrospective study of 58 children with moderate or severe traumatic brain injury due to abusive head trauma. Continuous electroencephalograms and magnetic resonance images were scored. Electrographic seizures (51.2%) and hypoxic-ischemic injury (77.4%) were common in our cohort. Younger age was associated with electrographic seizures (no seizures: median age 13.5 months, interquartile range five to 25 months, versus seizures: 4.5 months, interquartile range 3 to 9.5 months; P = 0.001). Severity of hypoxic-ischemic injury was also associated with seizures (no seizures: median injury score 1.0, interquartile range 0 to 3, versus seizures: 4.5, interquartile range 3 to 8; P = 0.01), but traumatic injury severity was not associated with seizures (no seizures: mean injury score 3.78 ± 1.68 versus seizures: mean injury score 3.83 ± 0.95, P = 0.89). There was a correlation between hypoxic-ischemic injury severity and seizure burden when controlling for patient age (r s =0.61, P interquartile range 0 to 0.23 on magnetic resonance imaging done within two days versus median restricted diffusion ratio 0.13, interquartile range 0.01 to 0.43 on magnetic resonance imaging done after two days, P = 0.03). Electrographic seizures are common in children with moderate to severe traumatic brain injury from abusive head trauma, and therefore children with suspected abusive head trauma should be monitored with continuous electroencephalogram. Severity of hypoxic-ischemic brain injury is correlated with severity of seizures, and evidence of hypoxic-ischemic injury on magnetic resonance imaging may evolve over time. Therefore children with a high seizure burden should be reimaged to evaluate for evolving hypoxic-ischemic injury. Published by Elsevier Inc.

Hemispheric distribution of middle cerebral artery ischemic strokes in patients admitted to military hospital rawalpindi

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Tariq, M.; Ishtiaq, S.; Zulfiqar, S.O.

2016-01-01

Objective: To determine the difference in the frequency of middle cerebral artery (MCA) ischemic strokes between left and right cerebral hemispheres in the adult patients admitted to the Military Hospital (MH) Rawalpindi. Study Design: A descriptive study. Place and Duration of Study: MH Rawalpindi from 01 Dec 2013 to 30 Mar 2014. Patients and Methods: Seventy eight adult patients admitted to MH Rawalpindi with neurologic deficits consistent with MCA strokes and having no evidence of intracerebral haemorrhage on Computed Tomographic (CT) scan of brain. Descriptive Statistics were calculated using SPSS version 17. Results: A total of 78 patients met the inclusion criteria of the study; 35 (45 percent) patients had right MCA stroke while 43 (55 percent) had left MCA stroke. Conclusion: Left MCA ischemic strokes are more common than right MCA ischemic strokes. (author)

Experimental model considerations for the study of protein-energy malnutrition co-existing with ischemic brain injury.

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Prosser-Loose, Erin J; Smith, Shari E; Paterson, Phyllis G

2011-05-01

Protein-energy malnutrition (PEM) affects ~16% of patients at admission for stroke. We previously modeled this in a gerbil global cerebral ischemia model and found that PEM impairs functional outcome and influences mechanisms of ischemic brain injury and recovery. Since this model is no longer reliable, we investigated the utility of the rat 2-vessel occlusion (2-VO) with hypotension model of global ischemia for further study of this clinical problem. Male, Sprague-Dawley rats were exposed to either control diet (18% protein) or PEM induced by feeding a low protein diet (2% protein) for 7d prior to either global ischemia or sham surgery. PEM did not significantly alter the hippocampal CA1 neuron death (p = 0.195 by 2-factor ANOVA) or the increase in dendritic injury caused by exposure to global ischemia. Unexpectedly, however, a strong trend was evident for PEM to decrease the consistency of hippocampal damage, as shown by an increased incidence of unilateral or no hippocampal damage (p=0.069 by chi-square analysis). Although PEM caused significant changes to baseline arterial blood pH, pO(2), pCO(2), and fasting glucose (p0.269). Intra-ischemic tympanic temperature and blood pressure were strictly and equally controlled between ischemic groups. We conclude that co-existing PEM confounded the consistency of hippocampal injury in the 2-VO model. Although the mechanisms responsible were not identified, this model of brain ischemia should not be used for studying this co-morbidity factor. © 2011 Bentham Science Publishers Ltd.

Protective Effect Of Bosentan In Experimental Cerebral Ischemia-Reperfusion Injury

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Eser Ataş

2013-02-01

Full Text Available OBJECTIVE: In cerebral ischemia, there are many factors that start the events leading to cell death. These factors contain free radical production, excitotoxicity, sodium and calcium flow disruption, enzymatic changes, stimulation of the inflamatuar process, the activation of platelets and leukocytes, delayed coagulation, endothelial dysfunction and endothelin (ET release. Bosentan is the competitive antagonist of endothelin receptors; ETA and ETB. The aim of this study is to determine whether the protective effects of bosentan in experimental cerebral ischemia reperfusion injury. MATERIAL and METHODS: In this study, after ischemia-reperfusion procedure, bosentan molecule was regularly given to rats for 5 days. The brain tissues of decapitated rats were histopathologically examined. The levels of oxidant and antioxidant were determined in these brain tissues. RESULTS: It was observed that antioxidant levels and histopathological examinations were in rats given bosentan better than control group rats. CONCLUSION: In conclusion, this study has showed that bosentan may be an agent which could reduce negative effects resulting from neuronal death associated with ischemic stroke.

Metabolite changes in the ipsilateral and contralateral cerebral hemispheres in rats with middle cerebral artery occlusion

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Lei Ruan

2017-01-01

difference in the metabolite changes induced by ischemic injury in the contralateral and ipsilateral cerebral hemispheres. Our findings demonstrate the presence of characteristic changes in metabolites in the contralateral hemisphere and suggest that they are most likely caused by metabolic changes in the ischemic hemisphere.

Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes.

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Perna, Robert; Temple, Jessica

2015-01-01

Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n = 172) or hemorrhagic stroke (n = 112) within the past six months and were involved in a postacute neurorehabilitation program. Participants completed three months of postacute neurorehabilitation and the Mayo Portland Adaptability Inventory-4 (MPAI-4) at admission and discharge. Admission MPAI-4 scores and level of functioning were comparable. Results. Group ANOVA comparisons show no significant group differences at admission or discharge or difference in change scores. Both groups showed considerably reduced levels of productivity/employment after discharge as compared to preinjury levels. Conclusions. Though the pathophysiology of these types of strokes is different, both ultimately result in ischemic injuries, possibly accounting for lack of findings of differences between groups. In the present study, participants in both groups experienced similar functional levels across all three MPAI-4 domains both at admission and discharge. Limitations of this study include a highly educated sample and few outcome measures.

Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes

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Robert Perna

2015-01-01

Full Text Available Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n=172 or hemorrhagic stroke (n=112 within the past six months and were involved in a postacute neurorehabilitation program. Participants completed three months of postacute neurorehabilitation and the Mayo Portland Adaptability Inventory-4 (MPAI-4 at admission and discharge. Admission MPAI-4 scores and level of functioning were comparable. Results. Group ANOVA comparisons show no significant group differences at admission or discharge or difference in change scores. Both groups showed considerably reduced levels of productivity/employment after discharge as compared to preinjury levels. Conclusions. Though the pathophysiology of these types of strokes is different, both ultimately result in ischemic injuries, possibly accounting for lack of findings of differences between groups. In the present study, participants in both groups experienced similar functional levels across all three MPAI-4 domains both at admission and discharge. Limitations of this study include a highly educated sample and few outcome measures.

Mechanisms of gender-linked ischemic brain injury

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Liu, Mingyue; Dziennis, Suzan; Hurn, Patricia D.; Alkayed, Nabil J.

2010-01-01

Biological sex is an important determinant of stroke risk and outcome. Women are protected from cerebrovascular disease relative to men, an observation commonly attributed to the protective effect of female sex hormones, estrogen and progesterone. However, sex differences in brain injury persist well beyond the menopause and can be found in the pediatric population, suggesting that the effects of reproductive steroids may not completely explain sexual dimorphism in stroke. We review recent advances in our understanding of sex steroids (estradiol, progesterone and testosterone) in the context of ischemic cell death and neuroprotection. Understanding the molecular and cell-based mechanisms underlying sex differences in ischemic brain injury will lead to a better understanding of basic mechanisms of brain cell death and is an important step toward designing more effective therapeutic interventions in stroke. PMID:19531872

Intake of antioxidants and B vitamins is inversely associated with ischemic stroke and cerebral atherosclerosis

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Choe, Hansaem; Hwang, Ji-Yun; Yun, Jin A; Kim, Ji-Myung; Song, Tae-Jin; Chang, Namsoo; Kim, Yong-Jae

2016-01-01

BACKGROUND/OBJECTIVES This study was conducted to examine relationships between dietary habits and intakes of antioxidants and B vitamins and the risk of ischemic stroke, and to compare dietary factors according to the presence of cerebral artery atherosclerosis and stroke subtypes. SUBJECTS/METHODS A total of 147 patients and 144 control subjects were recruited consecutively in the metropolitan area of Seoul, Korea. Sixty participants each in the case and control groups were included in analyses after 1:1 frequency matching. In addition, 117 acute ischemic stroke patients were classified into subtypes according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) guidelines. Dietary intake was measured using a semi-quantitative food frequency questionnaire composed of 111 food items and plasma lipid and homocysteine levels were analyzed. RESULTS When compared with control subjects, stroke patients had unfavorable dietary behaviors and lower intakes of fruits (73.1 ± 83.2 g vs. 230.9 ± 202.1 g, P < 0.001), vegetables (221.1 ± 209.0 g vs. 561.7 ± 306.6 g, P < 0.001), and antioxidants, including vitamins C, E, B6, β-carotene, and folate. The intakes of fruits, vegetables, vitamin C, and folate were inversely associated with the risk of ischemic stroke after adjusting for confounding factors. Intakes of vegetables, vitamins C, B6, B12, and folate per 1,000 kcal were lower in ischemic stroke with cerebral atherosclerosis than in those without. Overall vitamin B12 intake per 1,000 kcal differed according to the TOAST classification (P = 0.004), but no differences among groups existed based on the post-hoc test. CONCLUSIONS When compared with control subjects, ischemic stroke patients, particularly those with cerebral atherosclerosis, had unfavorable dietary intake, which may have contributed to the development of ischemic stroke. These results indicate that proper dietary recommendations are important for the prevention of ischemic stroke. PMID:27698959

PKA Inhibitor H89 (N-[2-p-bromocinnamylamino-ethyl]-5-isoquinolinesulfonamide Attenuates Synaptic Dysfunction and Neuronal Cell Death following Ischemic Injury

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Juhyun Song

2015-01-01

Full Text Available The cyclic AMP-dependent protein kinase (PKA, which activates prosurvival signaling proteins, has been implicated in the expression of long-term potentiation and hippocampal long-term memory. It has come to light that H89 commonly known as the PKA inhibitor have diverse roles in the nervous system that are unrelated to its role as a PKA inhibitor. We have investigated the role of H89 in ischemic and reperfusion injury. First, we examined the expression of postsynaptic density protein 95 (PSD95, microtubule-associated protein 2 (MAP2, and synaptophysin in mouse brain after middle cerebral artery occlusion injury. Next, we examined the role of H89 pretreatment on the expression of brain-derived neurotrophic factor (BDNF, PSD95, MAP2, and the apoptosis regulators Bcl2 and cleaved caspase-3 in cultured neuroblastoma cells exposed to hypoxia and reperfusion injury. In addition, we investigated the alteration of AKT activation in H89 pretreated neuroblastoma cells under hypoxia and reperfusion injury. The data suggest that H89 may contribute to brain recovery after ischemic stroke by regulating neuronal death and proteins related to synaptic plasticity.

Cerebral postischemic hyperperfusion in PET and SPECT

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Cho, Inn Ho

2001-01-01

Cerebral post-ischemic hyperperfusion has been observed at the acute and subacute periods of ischemic stroke. In the animal stroke model, early post-ischemic hyperperfusion is the mark of recanalization of the occluded artery with reperfusion. In the PET studies to both humans and experimental animals, early post-ischemic hyperperfusion is not a key factor in the development of tissue infarction and indicates the spontaneous reperfusion of the ischemic brain tissue without late infarction or with small infarction. But late post-ischemic hyperperfusion shows the worse prognosis with reperfusion injury associated with brain tissue necrosis. Early post-ischemic hyperperfusion defined by PET and SPECT may be useful in predicting the prognosis of ischemic stroke and the effect of thrombolytic therapy

Neurological Injury and Cerebral Blood Flow in Single Ventricles Throughout Staged Surgical Reconstruction.

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Fogel, Mark A; Li, Christine; Elci, Okan U; Pawlowski, Tom; Schwab, Peter J; Wilson, Felice; Nicolson, Susan C; Montenegro, Lisa M; Diaz, Laura; Spray, Thomas L; Gaynor, J William; Fuller, Stephanie; Mascio, Christopher; Keller, Marc S; Harris, Matthew A; Whitehead, Kevin K; Bethel, Jim; Vossough, Arastoo; Licht, Daniel J

2017-02-14

Patients with a single ventricle experience a high rate of brain injury and adverse neurodevelopmental outcome; however, the incidence of brain abnormalities throughout surgical reconstruction and their relationship with cerebral blood flow, oxygen delivery, and carbon dioxide reactivity remain unknown. Patients with a single ventricle were studied with magnetic resonance imaging scans immediately prior to bidirectional Glenn (pre-BDG), before Fontan (BDG), and then 3 to 9 months after Fontan reconstruction. One hundred sixty-eight consecutive subjects recruited into the project underwent 235 scans: 63 pre-BDG (mean age, 4.8±1.7 months), 118 BDG (2.9±1.4 years), and 54 after Fontan (2.4±1.0 years). Nonacute ischemic white matter changes on T2-weighted imaging, focal tissue loss, and ventriculomegaly were all more commonly detected in BDG and Fontan compared with pre-BDG patients ( P <0.05). BDG patients had significantly higher cerebral blood flow than did Fontan patients. The odds of discovering brain injury with adjustment for surgical stage as well as ≥2 coexisting lesions within a patient decreased (63%-75% and 44%, respectively) with increasing amount of cerebral blood flow ( P <0.05). In general, there was no association of oxygen delivery (except for ventriculomegaly in the BDG group) or carbon dioxide reactivity with neurological injury. Significant brain abnormalities are commonly present in patients with a single ventricle, and detection of these lesions increases as children progress through staged surgical reconstruction, with multiple coexisting lesions more common earlier than later. In addition, this study demonstrated that BDG patients had greater cerebral blood flow than did Fontan patients and that an inverse association exists of various indexes of cerebral blood flow with these brain lesions. However, CO 2 reactivity and oxygen delivery (with 1 exception) were not associated with brain lesion development. URL: http

Investigation of cerebral iron deposition in aged patients with ischemic cerebrovascular disease using susceptibility-weighted imaging

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Liu Y

2016-08-01

Full Text Available Yin Liu, Jun Liu, Huanghui Liu, Yunjie Liao, Lu Cao, Bin Ye, Wei Wang Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, People’s Republic of China Objective: The aim of this study was to investigate focal iron deposition level in the brain in patients with ischemic cerebrovascular disease and its correlation with cerebral small vessel disease imaging markers.Patients and methods: Seventy-four patients with first-ever transient ischemic attack (median age: 69 years; 30 males and 44 females and 77 patients with positive ischemic stroke history (median age: 72 years; 43 males and 34 females were studied retrospectively. On phase image of susceptibility-weighted imaging and regions of interest were manually drawn at the bilateral head of the caudate nucleus, lenticular nucleus (LN, thalamus (TH, frontal white matter, and occipital white matter. The correlation between iron deposition level and the clinical and imaging variables was also investigated.Results: Iron deposition level at LN was significantly higher in patients with previous stroke history. It linearly correlated with the presence and number of cerebral microbleeds (CMBs but not with white matter hyperintensity and lacunar infarct. Multiple linear regression analysis showed that deep structure CMBs were the most relevant in terms of iron deposition at LN.Conclusion: Iron deposition at LN may increase in cases of more severe ischemia in aged patients with transient ischemic attack, and it may be an imaging marker for CMB of ischemic origin. Keywords: cerebral microbleed, ischemia, susceptibility-weighted imaging, iron, lenticular nucleus

In vivo measurements of cerebral metabolic abnormalities by proton spectroscopy after a transient ischemic attack revealing an internal carotid stenosis > 70%

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Giroud, M.; Becker, F.; Lemesle, M.; Walker, P.; Guy, F.; Martin, D.; Baudouin, N.; Brunotte, F.; Dumas, R.

1996-01-01

Aims: The aim of this work is to look for cerebral metabolic abnormalities within the first 3 days after a transient ischemic attack revealing an internal carotid stenosis > 70 %. Methods: Five patients with a transient ischemic attack lasting between 30 and 180 minutes, affecting sensory and motor brachio-facial territory, with or without aphasia. Were studied. A CT-scan, an EEG, a cervical Doppler ultrasound, a standard arteriography, a magnetic resonance imaging and a proton spectroscopy were performed within the cerebral area affected by the transient ischemic attack. We measured 2 markers: N-acetyl-aspartate, the marker of the neuronal mass, and lactate, the marker of anaerobe metabolism. In each case, a contralateral internal stenosis was diagnosed by cervical Doppler ultrasound and standard arteriography. No cerebral infarction was observed. Results: With the affected cerebral area defined according to clinical and EEG features, proton spectroscopy showed a significant rise of lactate, without any change in N-acetyl-aspartate levels. Conclusions: Within the first 3 days after a transient ischemic attack, there is a significant risk of lactate inside the affected cerebral area. This change may reflect a localized and transient hypoperfusion, but long enough to induce a rise of lactate but not sufficient to produce a cerebral infarct. This area is probably at risk to induce cerebral infarct. This data lead us to study the metabolic change induced by the asymptomatic internal carotid stenosis. (authors). 18 refs

Blunt Traumatic Extracranial Cerebrovascular Injury and Ischemic Stroke

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Paul M. Foreman

2017-04-01

Full Text Available Background: Ischemic stroke occurs in a significant subset of patients with blunt traumatic cerebrovascular injury (TCVI. The patients are victims of motor vehicle crashes, assaults or other high-energy collisions, and suffer ischemic stroke due to injury to the extracranial carotid or vertebral arteries. Summary: An increasing number of patients with TCVI are being identified, largely because of the expanding use of computed tomography angiography for screening patients with blunt trauma. Patients with TCVI are particularly challenging to manage because they often suffer polytrauma, that is, numerous additional injuries including orthopedic, chest, abdominal, and head injuries. Presently, there is no consensus about optimal management. Key Messages: Most literature about TCVI and stroke has been published in trauma, general surgery, and neurosurgery journals; because of this, and because these patients are managed primarily by trauma surgeons, patients with stroke due to TCVI have been essentially hidden from view of neurologists. This review is intended to bring this clinical entity to the attention of clinicians and investigators with specific expertise in neurology and stroke.

Frequency of cerebral infarction secondary to head injury and the underlying mechanisms: CT study

International Nuclear Information System (INIS)

Fernande-Fresno, L.; Manzanares, R.; Caniego, J.L.; Velasco, M.; Parra, M.L.; Monasterio, F.

1997-01-01

To study the frequency of and possible mechanisms producing severe head injury (HI) by serial CT studies. We reviewed brain CT results in 154 HI patients examined over the past 31 months. All of them were hospitalized in the Intensive Care Unit (ICU) presenting coma with Glosgow Coma Scale scores of 9 or under. A first CT scan was performed when the patients arrived in the emergency room and at a least one more was carried out over the following 1 to 6 days. Sixteen of the 154 patients presented ischemic areas of low attenuation in a territory of defined vascular distribution that did not exist in the CT done at admission; the majority of them also had extensive extraaxial or intraaxial hematomas causing a considerable mass effect and cerebral displacement inducing different types of herniation. The vascular territories involved were anterior cerebral artery in five cases, middle cerebral artery in two, posterior cerebral artery in seven lenticulostriate arteries in six, anterior choroidal artery in five, perforating thalamus in six, recurrent artery in one case and superior cerebellar artery in another. In our series, there was a high prevalence (10.4%) of infarcts associated with severe HI; the most common etiopathogenic mechanisms are cerebral displacement accompanied by compression and vessel strain. (Author) 13 refs

Protective Effect of Ischemic Postconditioning against Ischemia Reperfusion-Induced Myocardium Oxidative Injury in IR Rats

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Jiangwei Ma

2012-03-01

Full Text Available Brief episodes of myocardial ischemia-reperfusion (IR employed during reperfusion after a prolonged ischemic insult may attenuate the total ischemia-reperfusion injury. This phenomenon has been termed ischemic postconditioning. In the present study, we studied the possible effect of ischemic postconditioning on an ischemic reperfusion (IR-induced myocardium oxidative injury in rat model. Results showed that ischemic postconditioning could improve arrhythmia cordis, reduce myocardium infarction and serum creatin kinase (CK, lactate dehydrogenase (LDH and aspartate transaminase (AST activities in IR rats. In addition, ischemic postconditioning could still decrease myocardium malondialdehyde (MDA level, and increased myocardium Na+-K+-ATPase, Ca2+-Mg2+-ATPase, superoxide dismutase (SOD, catalase (CAT, glutathione peroxidase (GSH-Px and glutathione reductase (GR activities. It can be concluded that ischemic postconditioning possesses strong protective effects against ischemia reperfusion-induced myocardium oxidative injury in IR rats.

Probucol plus cilostazol attenuate hypercholesterolemia‑induced exacerbation in ischemic brain injury via anti-inflammatory effects.

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Kim, Ji Hyun; Hong, Ki Whan; Bae, Sun Sik; Shin, Yong-Il; Choi, Byung Tae; Shin, Hwa Kyoung

2014-09-01

Probucol, a lipid-lowering agent with anti-oxidant properties, is involved in protection against atherosclerosis, while cilostazol, an antiplatelet agent, has diverse neuroprotective properties. In this study, we investigated the anti-inflammatory effects of probucol and cilostazol on focal cerebral ischemia with hypercholesterolemia. Apolipoprotein E (ApoE) knockout (KO) mice were fed a high-fat diet (HFD) with or without 0.3% probucol and/or 0.2% cilostazol for 10 weeks. To assess the protective effects of the combined therapy of probucol and cilostazol on ischemic injury, the mice received 40 min of middle cerebral artery occlusion (MCAO). Infarct volumes, neurobehavioral deficits and neuroinflammatory mediators were subsequently evaluated 48 h after reperfusion. Probucol alone and probucol plus cilostazol significantly decreased total- and low-density lipoprotein (LDL)-cholesterol in ApoE KO with HFD. MCAO resulted in significantly larger infarct volumes in ApoE KO mice provided with HFD compared to those fed a regular diet, although these volumes were significantly reduced in the probucol plus cilostazol group. Consistent with a smaller infarct size, probucol alone and the combined treatment of probucol and cilostazol improved neurological and motor function. In addition, probucol alone and probucol plus cilostazol decreased MCP-1 expression and CD11b and GFAP immuno-reactivity in the ischemic cortex. These findings suggested that the inhibitory effects of probucol plus cilostazol in MCP-1 expression in the ischemic brain with hypercholesterolemia allowed the identification of one of the mechanisms responsible for anti-inflammatory action. Probucol plus cilostazol may therefore serve as a therapeutic strategy for reducing the impact of stroke in hypercholesterolemic subjects.

Severe hypertriglyceridemia does not protect from ischemic brain injury in gene-modified hypertriglyceridemic mice.

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Chen, Yong; Liu, Ping; Qi, Rong; Wang, Yu-Hui; Liu, George; Wang, Chun

2016-05-15

Hypertriglyceridemia (HTG) is a weak risk factor in primary ischemic stroke prevention. However, clinical studies have found a counterintuitive association between a good prognosis after ischemic stroke and HTG. This "HTG paradox" requires confirmation and further explanation. The aim of this study was to experimentally assess this paradox relationship using the gene-modified mice model of extreme HTG. We first used the human Apolipoprotein CIII transgenic (Tg-ApoCIII) mice and non-transgenic (Non-Tg) littermates to examine the effect of HTG on stroke. To our surprise, infarct size, neurological deficits, brain edema, BBB permeability, neuron density and lipid peroxidation were the same in Tg-ApoCIII mice and Non-Tg mice after temporary middle cerebral artery occlusion (tMCAO). In the late phase (21 days after surgery), no differences were found in brain atrophy, neurological dysfunctions, weight and mortality between the two groups. To confirm the results in Tg-ApoCIII mice, Glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1(GPIHBP1) knockout mice, another severe HTG mouse model, were used and yielded similar results. Our study demonstrates for the first time that extreme HTG does not affect ischemic brain injuries in the tMCAO mouse model, indicating that the association between HTG and good outcomes after ischemic stroke probably represents residual unmeasured confounding. Further clinical and prospective population-based studies are needed to explore variables that contribute to the paradox. Copyright © 2016 Elsevier B.V. All rights reserved.

Histone acetylation and CREB binding protein are required for neuronal resistance against ischemic injury.

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Ferah Yildirim

Full Text Available Epigenetic transcriptional regulation by histone acetylation depends on the balance between histone acetyltransferase (HAT and deacetylase activities (HDAC. Inhibition of HDAC activity provides neuroprotection, indicating that the outcome of cerebral ischemia depends crucially on the acetylation status of histones. In the present study, we characterized the changes in histone acetylation levels in ischemia models of focal cerebral ischemia and identified cAMP-response element binding protein (CREB-binding protein (CBP as a crucial factor in the susceptibility of neurons to ischemic stress. Both neuron-specific RNA interference and neurons derived from CBP heterozygous knockout mice showed increased damage after oxygen-glucose deprivation (OGD in vitro. Furthermore, we demonstrated that ischemic preconditioning by a short (5 min subthreshold occlusion of the middle cerebral artery (MCA, followed 24 h afterwards by a 30 min occlusion of the MCA, increased histone acetylation levels in vivo. Ischemic preconditioning enhanced CBP recruitment and histone acetylation at the promoter of the neuroprotective gene gelsolin leading to increased gelsolin expression in neurons. Inhibition of CBP's HAT activity attenuated neuronal ischemic preconditioning. Taken together, our findings suggest that the levels of CBP and histone acetylation determine stroke outcome and are crucially associated with the induction of an ischemia-resistant state in neurons.

Feasibility of arterial blood bypass using microcatheter in intraarterial thrombolysis for acute cerebral ischemic stroke

International Nuclear Information System (INIS)

Wang Wei; Li Cheng; Liu Zhensheng; Zhang Xinjiang; Zhou Longjiang; Yin Haiyan

2010-01-01

Objective: To assess the feasibility of arterial blood bypass using microcatheter in intraarterial thrombolysis for acute cerebral ischemic stroke. Methods: Six patients with acute cerebral infarction within 6 hours underwent intraarterial thrombolysis, in which arterial blood bypass was used. A 2.3 F microcatheter was advanced through the clot and two milliliters of contrast was injected beyond the clot that remained stagnant in the major branches. At this point, 20 ml of oxygenated blood from femoral artery was injected for 2 minutes through the microcatheter past the occluding clot. Then, conventional intraarterial thrombolysis, including fibrinolytic agents infusion and mechanical disruption, was performed. Intraarterial thrombolysis and oxygenated blood infusion alternated every 30 minutes. Results: Every patient received arterial blood bypass with average three times (from 1 to 5 times) in the process of the intraarterial thrombolysis, which cost (8.0 ± 3.2) min. Recanalization was achieved in all 6 patients, but minor subarachnoid hemorrhage developed in one patient. All the patients got favorable clinical outcome. The life conditions is excellent in 4 cases and good in 2 cases. Conclusions: Arterial blood bypass using microcatheter in intraarterial thrombolysis for acute cerebral ischemic stroke might be feasible, which did not interfere with conventional intraarterial thrombolysis and prolong the operation time significantly but could protect ischemic penumbra. (authors)

Homocysteine Aggravates Cortical Neural Cell Injury through Neuronal Autophagy Overactivation following Rat Cerebral Ischemia-Reperfusion

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Yaqian Zhao

2016-07-01

Full Text Available Elevated homocysteine (Hcy levels have been reported to be involved in neurotoxicity after ischemic stroke. However, the underlying mechanisms remain incompletely understood to date. In the current study, we hypothesized that neuronal autophagy activation may be involved in the toxic effect of Hcy on cortical neurons following cerebral ischemia. Brain cell injury was determined by hematoxylin-eosin (HE staining and TdT-mediated dUTP Nick-End Labeling (TUNEL staining. The level and localization of autophagy were detected by transmission electron microscopy, western blot and immunofluorescence double labeling. The oxidative DNA damage was revealed by immunofluorescence of 8-Hydroxy-2′-deoxyguanosine (8-OHdG. Hcy treatment aggravated neuronal cell death, significantly increased the formation of autophagosomes and the expression of LC3B and Beclin-1 in the brain cortex after middle cerebral artery occlusion-reperfusion (MCAO. Immunofluorescence analysis of LC3B and Beclin-1 distribution indicated that their expression occurred mainly in neurons (NeuN-positive and hardly in astrocytes (GFAP-positive. 8-OHdG expression was also increased in the ischemic cortex of Hcy-treated animals. Conversely, LC3B and Beclin-1 overexpression and autophagosome accumulation caused by Hcy were partially blocked by the autophagy inhibitor 3-methyladenine (3-MA. Hcy administration enhanced neuronal autophagy, which contributes to cell death following cerebral ischemia. The oxidative damage-mediated autophagy may be a molecular mechanism underlying neuronal cell toxicity of elevated Hcy level.

Neuroprotective Effect of β-Caryophyllene on Cerebral Ischemia-Reperfusion Injury via Regulation of Necroptotic Neuronal Death and Inflammation: In Vivo and in Vitro

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Mei Yang

2017-10-01

Full Text Available Necrotic cell death is a hallmark feature of ischemic stroke and it may facilitate inflammation by releasing intracellular components after cell-membrane rupture. Previous studies reported that β-caryophyllene (BCP mitigates cerebral ischemia-reperfusion (I/R injury, but the underlying mechanism remains unclear. We explored whether BCP exerts a neuroprotective effect in cerebral I/R injury through inhibiting necroptotic cell death and inflammation. Primary neurons with and without BCP (0.2, 1, 5, 25 μM treatment were exposed to oxygen-glucose deprivation and re-oxygenation (OGD/R. Neuron damage, neuronal death type and mixed lineage kinase domain-like (MLKL protein expression were assessed 48 h after OGD/R. Furthermore, mice underwent I/R procedures with or without BCP (8, 24, 72 mg/kg, ip.. Neurologic dysfunction, cerebral infarct volumes, cell death, cytokine levels, necroptosis core molecules, and HMGB1-TLR4 signaling were determined at 48 h after I/R. BCP (5 μM significantly reduced necroptotic neurons and MLKL protein expression following OGD/R. BCP (24, 72 mg/kg, ip. reduced infarct volumes, neuronal necrosis, receptor-interaction protein kinase-1 (RIPK1, receptor-interaction protein kinase-3 (RIPK3 expression, and MLKL phosphorylation after I/R injury. BCP also decreased high-mobility group box 1 (HMGB1, toll-like receptor 4 (TLR4, interleukin-1β (IL-1β, and tumor necrosis factor-α (TNF-α levels. Thus, BCP alleviates ischemic brain damage potentially by inhibiting necroptotic neuronal death and inflammatory response. This study suggests a novel application for BCP as a neuroprotective agent.

Detection of focal hypoxic-ischemic injury and neuronal stress in a rodent model of unilateral MCA occlusion/reperfusion using radiolabeled annexin V

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Mari, Carina; Goris, Michael L. [Division of Nuclear Medicine, Department of Radiology, Stanford University Hospital, CA 94305, Stanford (United States); Karabiyikoglu, Murat; Yenari, Midori Anne [Departments of Neurosurgery and Neurology, Stanford University Hospital, CA 94305, Stanford (United States); Tait, Jonathan F. [Department of Laboratory Medicine, University of Washington Medical Center, WA 98195-7110, Seattle (United States); Blankenberg, Francis G. [Division of Nuclear Medicine, Department of Radiology, Stanford University Hospital, CA 94305, Stanford (United States); Division of Pediatric Radiology, Department of Radiology, Stanford University, Lucile Salter Packard Children' s Hospital, 725 Welch Road, Room 1673, CA 94305, Palo Alto (United States)

2004-05-01

In this study we wished to determine whether technetium-99m annexin V, an in vivo marker of cellular injury and death, could be used to noninvasively monitor neuronal injury following focal middle cerebral artery (MCA) occlusion/reperfusion injury. Sixteen adult male Sprague-Dawley rats (along with four controls) underwent left (unilateral) MCA intraluminal beaded thread occlusion for 2 h followed by reperfusion. One hour following tail vein injection of 5-10 mCi of {sup 99m}Tc-annexin V, animals underwent either single-photon emission computerized tomography (SPECT) or autoradiography followed by immunohistochemical analyses. There was abnormal, bilateral, multifocal uptake of {sup 99m}Tc-annexin V in each cerebral hemisphere as seen by both SPECT and autoradiography at 4 h and 1, 3, and 7 days after initiation of occlusion. The average maximal annexin V uptake at 4 h was 310%{+-}85% and 365%{+-}151% above control values (P<0.006) within the right and left hemispheres, respectively, peaking on day 3 with values of 925%{+-}734% and 1,194%{+-}643% (P<0.03) that decreased by day 7 to 489%{+-}233% and 785%{+-}225% (P<0.01). Total lesional volume of the left hemisphere was 226%, 261%, and 451% (P<0.03) larger than the right at 4, 24, and 72 h after injury, respectively. Annexin V localized to the cytoplasm of injured neurons ipsilateral to the site of injury as well as to otherwise normal-appearing neurons of the contralateral hemisphere as confirmed by dual fluorescent microscopy. It is concluded that there is abnormal bilateral, multifocal annexin V uptake, greater on the left than on the right side, within 4 h of unilateral left MCA ischemic injury and that the uptake peaks at 3 days and decreases by 7 days after injury. This pattern suggests that neuronal stress may play a role in the response of the brain to focal injury and be responsible for annexin V uptake outside the region of ischemic insult. (orig.)

Studies on cerebral protection of digoxin against ischemia/reperfusion injury in mice.

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Kaur, Shaminder; Rehni, Ashish K; Singh, Nirmal; Jaggi, Amteshwar S

2009-04-01

The present study was designed to investigate the possible neuroprotective effect of digoxin induced pharmacological preconditioning (PP) and its probable mechanism. Bilateral carotid artery occlusion (BCAO) of 17 min followed by reperfusion for 24 h was employed to produce ischemia and reperfusion (I/R) induced cerebral injury in male swiss albino mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was assessed using elevated plus maze test. Degree of motor incoordination was evaluated using inclined beam walking test, rota rod test and lateral push test. Digoxin (0.08 mg/kg, i.p.) was administered 24 h before surgery in a separate group of animals to induce PP. BCAO followed by reperfusion, produced significant rise in cerebral infarct size along with impairment of memory and motor coordination. Digoxin treatment produced a significant decrease in cerebral infarct size and reversal of I/R induced impairment of memory and motor incoordination. Digoxin induced neuroprotective effect was abolished significantly by verapamil (15 mg/kg, i.p.), a L-type calcium channel blocker, ruthenium red (3 mg/kg, s.c.), an intracellular ryanodine receptor blocker and 3,4-dichlorobenzamil (Na(+)/Ca(2+) exchanger inhibitor). These findings indicate that digoxin preconditioning exerts a marked neuroprotective effect on the ischemic brain, which is possibly linked to digitalis induced increase in intracellular calcium levels eventually leading to the activation of calcium sensitive signal transduction cascades.

Imaging findings and cerebral perfusion in arterial ischemic stroke due to transient cerebral arteriopathy in children; Achados de imagem e perfusao arterial cerebral em acidente vascular cerebral isquemico devido a arteriopatia transitoria em crianca

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Barbosa Junior, Alcino Alves, E-mail: alcinojr@uol.com.br [Departamento de Diagnostico por Imagem, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Ellovitch, Saada Resende de Souza [Neuropediatria, Hospital Israelita Albert Einstein - HIAE, Sao Paulo, SP (Brazil); Pincerato, Rita de Cassia Maciel [Hospital Samaritano, Sao Paulo, SP (Brazil)

2012-04-15

We report the case of a 4-year-old female child who developed an arterial ischemic stroke in the left middle cerebral artery territory, due to a proximal stenosis of the supraclinoid internal carotid artery, most probably related to transient cerebral arteriopathy of childhood. Computed tomography scan, magnetic resonance imaging, perfusion magnetic resonance and magnetic resonance angiography are presented, as well as follow-up by magnetic resonance and magnetic resonance angiography exams. Changes in cerebral perfusion and diffusion-perfusion mismatch call attention. As far as we know, this is the first report of magnetic resonance perfusion findings in transient cerebral arteriopathy. (author)

Adding left atrial appendage closure to open heart surgery provides protection from ischemic brain injury six years after surgery independently of atrial fibrillation history: the LAACS randomized study.

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Park-Hansen, Jesper; Holme, Susanne J V; Irmukhamedov, Akhmadjon; Carranza, Christian L; Greve, Anders M; Al-Farra, Gina; Riis, Robert G C; Nilsson, Brian; Clausen, Johan S R; Nørskov, Anne S; Kruuse, Christina R; Rostrup, Egill; Dominguez, Helena

2018-05-23

Open heart surgery is associated with high occurrence of atrial fibrillation (AF), subsequently increasing the risk of post-operative ischemic stroke. Concomitant with open heart surgery, a cardiac ablation procedure is commonly performed in patients with known AF, often followed by left atrial appendage closure with surgery (LAACS). However, the protective effect of LAACS on the risk of cerebral ischemia following cardiac surgery remains controversial. We have studied whether LAACS in addition to open heart surgery protects against post-operative ischemic brain injury regardless of a previous AF diagnosis. One hundred eighty-seven patients scheduled for open heart surgery were enrolled in a prospective, open-label clinical trial and randomized to concomitant LAACS vs. standard care. Randomization was stratified by usage of oral anticoagulation (OAC) planned to last at least 3 months after surgery. The primary endpoint was a composite of post-operative symptomatic ischemic stroke, transient ischemic attack or imaging findings of silent cerebral ischemic (SCI) lesions. During a mean follow-up of 3.7 years, 14 (16%) primary events occurred among patients receiving standard surgery vs. 5 (5%) in the group randomized to additional LAACS (hazard ratio 0.3; 95% CI: 0.1-0.8, p = 0.02). In per protocol analysis (n = 141), 14 (18%) primary events occurred in the control group vs. 4 (6%) in the LAACS group (hazard ratio 0.3; 95% CI: 0.1-1.0, p = 0.05). In a real-world setting, LAACS in addition to elective open-heart surgery was associated with lower risk of post-operative ischemic brain injury. The protective effect was not conditional on AF/OAC status at baseline. LAACS study, clinicaltrials.gov NCT02378116 , March 4th 2015, retrospectively registered.

Dabrafenib, an inhibitor of RIP3 kinase-dependent necroptosis, reduces ischemic brain injury

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Shelly A Cruz

2018-01-01

Full Text Available Ischemic brain injury triggers neuronal cell death by apoptosis via caspase activation and by necroptosis through activation of the receptor-interacting protein kinases (RIPK associated with the tumor necrosis factor-alpha (TNF-α/death receptor. Recent evidence shows RIPK inhibitors are neuroprotective and alleviate ischemic brain injury in a number of animal models, however, most have not yet undergone clinical trials and safety in humans remains in question. Dabrafenib, originally identified as a B-raf inhibitor that is currently used to treat melanoma, was later revealed to be a potent RIPK3 inhibitor at micromolar concentrations. Here, we investigated whether Dabrafenib would show a similar neuroprotective effect in mice subjected to ischemic brain injury by photothrombosis. Dabrafenib administered intraperitoneally at 10 mg/kg one hour after photothrombosis-induced focal ischemic injury significantly reduced infarct lesion size in C57BL6 mice the following day, accompanied by a markedly attenuated upregulation of TNF-α. However, subsequent lower doses (5 mg/kg/day failed to sustain this neuroprotective effect after 4 days. Dabrafenib blocked lipopolysaccharides-induced activation of TNF-α in bone marrow-derived macrophages, suggesting that Dabrafenib may attenuate TNF-α-induced necroptotic pathway after ischemic brain injury. Since Dabrafenib is already in clinical use for the treatment of melanoma, it might be repurposed for stroke therapy.

Sulforaphane exerts neuroprotective effects via suppression of the inflammatory response in a rat model of focal cerebral ischemia

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Ma, Li-Li; Xing, Guo-Ping; Yu, Yin; Liang, Hui; Yu, Tian-Xia; Zheng, Wei-Hong; Lai, Tian-Bao

2015-01-01

Inflammatory damage plays an important role in cerebral ischemic pathogenesis and may represent a promising target for treatment. Sulforaphane exerts protective effects in a rat model of focal cerebral ischemia/reperfusion injury by alleviating brain edema. However, the possible mechanisms of sulforaphane after cerebral ischemia/reperfusion injury have not been fully elucidated. Therefore, in the present study, we investigated the effect of sulforaphane on inflammatory reaction and the potent...

Ketogenic Diet Provides Neuroprotective Effects against Ischemic Stroke Neuronal Damages

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Sheida Shaafi

2014-12-01

Full Text Available Ischemic stroke is a leading cause of death and disability in the world. Many mechanisms contribute in cell death in ischemic stroke. Ketogenic diet which has been successfully used in the drug-resistant epilepsy has been shown to be effective in many other neurologic disorders. The mechanisms underlying of its effects are not well studied, but it seems that its neuroprotective ability is mediated at least through alleviation of excitotoxicity, oxidative stress and apoptosis events. On the basis of these mechanisms, it is postulated that ketogenic diet could provide benefits to treatment of cerebral ischemic injuries.

Prdx6 Upregulation by Curcumin Attenuates Ischemic Oxidative Damage via SP1 in Rats after Stroke

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Gongwei Jia

2017-01-01

Full Text Available Background. The role of Peroxiredoxin 6 (Prdx6 in brain ischemia remains unclear. Curcumin (Cur treatment elicits neuroprotective effects against cerebral ischemic injury, and the associated mechanisms may involve Prdx6. In this study, we investigated whether Prdx6 and the transcription factor specific protein 1 (SP1 were involved in the antioxidant effect of Cur after stoke. Methods. Focal cerebral ischemic injury was induced by transient middle cerebral artery occlusion for 2 hours in male Sprague-Dawley rats treated with or without Prdx6 siRNA. Expression of Prdx6 in the penumbra was assessed by Real-Time PCR (RT-PCR, Western blot analysis, and immunoflourescent staining. In addition, infarct volume, neurological deficit score, and oxidative stress were evaluated. Prdx6 levels were also determined in the presence and absence of SP1 antagonist mithramycin A (MTM-A. Results. Cur treatment upregulated Prdx6 protein expression and the number of Prdx6-positive neuronal cells 24 hours after reperfusion. Cur treatment also attenuated oxidative stress and induced neuroprotective effects against ischemic damage, whereas the beneficial effects of Cur treatment were lost in animals treated with Prdx6-siRNA. Prdx6 upregulation by Cur treatment was abolished by SP1 antagonists MTM. Conclusions. Prdx6 upregulation by Cur treatment attenuates ischemic oxidative damage through SP1 induction in rats after stroke. This represents a novel mechanism of Cur-induced neuroprotection against cerebral ischemia.

Exercise preconditioning exhibits neuroprotective effects on hippocampal CA1 neuronal damage after cerebral ischemia

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Nabi Shamsaei; Mehdi Khaksari; Sohaila Erfani; Hamid Rajabi; Nahid Aboutaleb

2015-01-01

Recent evidence has suggested the neuroprotective effects of physical exercise on cerebral isch-emic injury. However, the role of physical exercise in cerebral ischemia-induced hippocampal damage remains controversial. The aim of the present study was to evaluate the effects of pre-ischemia treadmill training on hippocampal CA1 neuronal damage after cerebral ischemia. Male adult rats were randomly divided into control, ischemia and exercise + ischemia groups. In the exercise + ischemia group, rats were subjected to running on a treadmill in a designated time schedule (5 days per week for 4 weeks). Then rats underwent cerebral ischemia induction th rough occlusion of common carotids followed by reperfusion. At 4 days after cerebral ischemia, rat learning and memory abilities were evaluated using passive avoidance memory test and rat hippocampal neuronal damage was detected using Nissl and TUNEL staining. Pre-ischemic ex-ercise signiifcantly reduced the number of TUNEL-positive cells and necrotic cell death in the hippocampal CA1 region as compared to the ischemia group. Moreover, pre-ischemic exercise significantly prevented ischemia-induced memory dysfunction. Pre-ischemic exercise mighct prevent memory deficits after cerebral ischemia through rescuing hippocampal CA1 neurons from ischemia-induced degeneration.

Posttraumatic cerebral infarction due to progressive occlusion of the internal carotid artery after minor head injury in childhood: a case report.

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Matsumoto, Hiroaki; Kohno, Kanehisa

2011-07-01

Although minor head injury in childhood is a common occurrence and usually no complications, posttraumatic cerebral infarction has rarely been reported. Such infarction is characterized by occlusion of the lateral lenticulostriate artery. The authors report an atypical case of posttraumatic occlusion of the internal carotid artery (ICA) after minor head injury in childhood. A healthy 16-year-old boy was hit on the head by a pitch while playing baseball. He developed a transient ischemic attack involving the left extremities 15 min after the accident. Initial magnetic resonance imaging revealed neither hemorrhage nor infarction, and MR angiography demonstrated mild stenosis of the right carotid fork. Conservative therapy was started. However, 24 h after the accident, he suddenly developed left hemiparesis. Emergent neuroimaging demonstrated progressive occlusion of the supraclinoid portion of the right ICA and cerebral infarction of the deep white matter in the right frontal lobe. The hemiparesis deteriorated and the infarction area continued to expand on a daily. The patient underwent emergent superficial temporally artery-middle cerebral artery (STA-MCA) bypass. Intraoperative observation demonstrated that the supraclinoid portion of the right ICA was not thrombosed but pale with low tension and did not appear dissected. He fully recovered by 2 weeks after the operation. Postoperative investigations showed gradual improvement of the ICA occlusion. Minor head injury can cause cerebral infarction in childhood, although this is rare. If conservative therapy cannot prevent progressive cerebral infarction, STA-MCA bypass should be considered in case of the ICA occlusion.

Lysine and arginine reduce the effects of cerebral ischemic insults and inhibit glutamate-induced neuronal activity in rats

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Takashi Kondoh

2010-06-01

Full Text Available Intravenous administration of arginine was shown to be protective against cerebral ischemic insults via nitric oxide production and possibly via additional mechanisms. The present study aimed at evaluating the neuroprotective effects of oral administration of lysine (a basic amino acid, arginine, and their combination on ischemic insults (cerebral edema and infarction and hemispheric brain swelling induced by transient middle cerebral artery occlusion/reperfusion in rats. Magnetic resonance imaging and 2,3,5-triphenyltetrazolium chloride staining were performed two days after ischemia induction. In control animals, the major edematous areas were observed in the cerebral cortex and striatum. The volumes associated with cortical edema were significantly reduced by lysine (2.0 g/kg, arginine (0.6 g/kg, or their combined administration (0.6 g/kg each. Protective effects of these amino acids on infarction were comparable to the inhibitory effects on edema formation. Interestingly, these amino acids, even at low dose (0.6 g/kg, were effective to reduce hemispheric brain swelling. Additionally, the effects of in vivo microiontophoretic (juxtaneuronal applications of these amino acids on glutamate-evoked neuronal activity in the ventromedial hypothalamus were investigated in awake rats. Glutamate-induced neuronal activity was robustly inhibited by microiontophoretic applications of lysine or arginine onto neuronal membranes. Taken together, our results demonstrate the neuroprotective effects of oral ingestion of lysine and arginine against ischemic insults (cerebral edema and infarction, especially in the cerebral cortex, and suggest that suppression of glutamate-induced neuronal activity might be the primary mechanism associated with these neuroprotective effects.

Dietary and plant polyphenols exert neuroprotective effects and improve cognitive function in cerebral ischemia

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Cerebral ischemia is caused by an interruption of blood flow to the brain which generally leads to irreversible brain damage. Ischemic injury is associated with vascular leakage, inflammation, tissue injury, and cell death. Cellular changes associated with ischemia include impairment of metabolism, ...

Tanshinone IIA attenuates the cerebral ischemic injury-induced increase in levels of GFAP and of caspases-3 and -8.

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Zhou, L; Bondy, S C; Jian, L; Wen, P; Yang, F; Luo, H; Li, W; Zhou, Jun

2015-03-12

Tanshinone IIA (TSA) is a lipid soluble agent derived from the root of Salvia miltiorrhiza (Danshen). This plant is a traditional Chinese herb, which has been used widely in China especially for enhancing circulation. However mechanisms underlying its efficacy remain poorly understood. The present study was designed to illuminate events that may underlie the apparently neuroprotective effects of TSA following ischemic insult. Adult Sprague-Dawley rats were subjected to transient focal cerebral ischemia by use of a middle cerebral artery occlusion model. They were then randomly divided into a sham-operated control group, and cerebral ischemia/reperfusion groups receiving a two-hour occlusion. Further subsets of groups received the same durations of occlusion or were sham-operated but then received daily i.p. injections of high or low doses of TSA, for seven or 15days. Hematoxylin and eosin staining revealed lesions in the entorhinal cortex of both rats subject to ischemia and to a lesser extent to those receiving TSA after surgery. Levels of glial fibrillary acidic protein (GFAP), caspase-3 and caspase-8, were quantified by both immunohistochemistry and Western blotting. TSA treatment after middle cerebral artery occlusion, markedly reduced infarct size, and reduced the expression of caspase-3 and caspase-8. These changes were considered protective and were generally proportional to the dose of TSA used. These results suggest that TSA may effect neuroprotection by way of reduction of the extent of cell inflammation and death within affected regions. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Electroacupuncture improves cerebral blood flow and attenuates moderate ischemic injury via Angiotensin II its receptors-mediated mechanism in rats.

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Li, Jing; He, Jiaojun; Du, Yuanhao; Cui, Jingjun; Ma, Ying; Zhang, Xuezhu

2014-11-11

To investigate the effects and potential mechanism of electroacupuncture intervention on expressions of Angiotensin II and its receptors-mediated signaling pathway in experimentally induced cerebral ischemia. Totally 126 male Wistar rats were randomly divided into control group, model group and EA group. The latter two were further divided into ten subgroups (n = 6) following Middle Cerebral Artery Occlusion (MCAO). Changes in regional cerebral blood flow (rCBF) and expressions of Angiotensin II and its receptors (AT1R, AT2R), as well as effector proteins in phosphatidyl inositol signal pathway were monitored before and at different times after MCAO. MCAO-induced decline of ipsilateral rCBF was partially suppressed by electroacupuncture, and contralateral blood flow was also superior to that of model group. Angiotensin II level was remarkably elevated immediately after MCAO, while electroacupuncture group exhibited significantly lower levels at 1 to 3 h and the value was significantly increased thereafter. The enhanced expression of AT1R was partially inhibited by electroacupuncture, while increased AT2R level was further induced. Electroacupuncture stimulation attenuated and postponed the upregulated-expressions of Gq and CaM these upregulations. ELISA results showed sharply increased expressions of DAG and IP3, which were remarkably neutralized by electroacupuncture. MCAO induced significant increases in expression of Angiotensin II and its receptor-mediated signal pathway. These enhanced expressions were significantly attenuated by electroacupuncture intervention, followed by reduced vasoconstriction and improved blood supply in ischemic region, and ultimately conferred beneficial effects on cerebral ischemia.

Ginsenoside Rg1 improves ischemic brain injury by balancing ...

African Journals Online (AJOL)

Ginsenoside Rg1 improves ischemic brain injury by balancing mitochondrial ... and autophagy-related proteins were determined by reat time-polymerase chain ... Treatment with autophagy inhibitors decreased the mitochondrial protective ...

Cerebral Microbleeds are an Independent Predictor of Hemorrhagic Transformation Following Intravenous Alteplase Administration in Acute Ischemic Stroke.

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Nagaraja, Nandakumar; Tasneem, Nudrat; Shaban, Amir; Dandapat, Sudeepta; Ahmed, Uzair; Policeni, Bruno; Olalde, Heena; Shim, Hyungsub; Samaniego, Edgar A; Pieper, Connie; Ortega-Gutierrez, Santiago; Leira, Enrique C; Adams, Harold P

2018-05-01

Intravenous alteplase (rt-PA) increases the risk of hemorrhagic transformation of acute ischemic stroke. The objective of our study was to evaluate clinical, laboratory, and imaging predictors on forecasting the risk of hemorrhagic transformation following treatment with rt-PA. We also evaluated the factors associated with cerebral microbleeds that increase the risk of hemorrhagic transformation. Consecutive patients with acute ischemic stroke admitted between January 1, 2009 and December 31, 2013 were included in the study if they received IV rt-PA, had magnetic resonance imaging (MRI) of the brain on admission, and computed tomography or MRI of the brain at 24 (18-36) hours later to evaluate for the presence of hemorrhagic transformation. The clinical data, lipid levels, platelet count, MRI, and computed tomography images were retrospectively reviewed. The study included 366 patients, with mean age 67 ± 15 years; 46% were women and 88% were white. The median National Institutes of Health Stroke Scale (NIHSS) score was 6 (interquartile range 3-15). Hemorrhagic transformation was observed in 87 (23.8%) patients and cerebral microbleeds were noted in 95 (25.9%). Patients with hemorrhagic transformation tended to be older, nonwhite, have atrial fibrillation, higher baseline NIHSS score, lower cholesterol and triglyceride levels, and cerebral microbleeds and nonlacunar infarcts. Patients with cerebral microbleeds were more likely to be older, have hypertension, hyperlipidemia, previous history of stroke, and prior use of antithrombotics. On multivariate analysis race, NIHSS score, nonlacunar infarct, and presence of cerebral microbleeds were independently associated with hemorrhagic transformation following treatment with rt-PA. Presence of cerebral microbleeds is an independent predictor of hemorrhagic transformation of acute ischemic stroke following treatment with rt-PA. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights

Inhibition of miR-15 Protects Against Cardiac Ischemic Injury

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Hullinger, Thomas G.; Montgomery, Rusty L.; Seto, Anita G.; Dickinson, Brent A.; Semus, Hillary M.; Lynch, Joshua M.; Dalby, Christina M.; Robinson, Kathryn; Stack, Christianna; Latimer, Paul A.; Hare, Joshua M.; Olson, Eric N.; van Rooij, Eva

2012-01-01

Rationale Myocardial infarction (MI) is a leading cause of death worldwide. Because endogenous cardiac repair mechanisms are not sufficient for meaningful tissue regeneration, MI results in loss of cardiac tissue and detrimental remodeling events. MicroRNAs (miRNAs) are small, noncoding RNAs that regulate gene expression in a sequence dependent manner. Our previous data indicate that miRNAs are dysregulated in response to ischemic injury of the heart and actively contribute to cardiac remodeling after MI. Objective This study was designed to determine whether miRNAs are dysregulated on ischemic damage in porcine cardiac tissues and whether locked nucleic acid (LNA)-modified anti-miR chemistries can target cardiac expressed miRNAs to therapeutically inhibit miR-15 on ischemic injury. Methods and Results Our data indicate that the miR-15 family, which includes 6 closely related miRNAs, is regulated in the infarcted region of the heart in response to ischemia-reperfusion injury in mice and pigs. LNA-modified chemistries can effectively silence miR-15 family members in vitro and render cardiomyocytes resistant to hypoxia-induced cardiomyocyte cell death. Correspondingly, systemic delivery of miR-15 anti-miRs dose-dependently represses miR-15 in cardiac tissue of both mice and pigs, whereas therapeutic targeting of miR-15 in mice reduces infarct size and cardiac remodeling and enhances cardiac function in response to MI. Conclusions Oligonucleotide-based therapies using LNA-modified chemistries for modulating cardiac miRNAs in the setting of heart disease are efficacious and validate miR-15 as a potential therapeutic target for the manipulation of cardiac remodeling and function in the setting of ischemic injury. PMID:22052914

Posterior Cerebral Infarction following Loss of Guide Wire

OpenAIRE

Bugnicourt, Jean-Marc; Belhomme, Denis; Bonnaire, Bruno; Constans, Jean-Marc; Manaouil, Cécile

2013-01-01

Stroke after internal jugular venous cannulation typically leads to acute carotid or vertebral arteries injury and cerebral ischemia. We report the first case of delayed posterior cerebral infarction following loss of guide wire after left internal jugular venous cannulation in a 46-year-old woman with a history of inflammatory bowel disease. Our observation highlights that loss of an intravascular guide wire can be a cause of ischemic stroke in patients undergoing central venous catheterizat...

Cerebral blood flow in acute and chronic ischemic stroke using xenon-133 inhalation tomography

DEFF Research Database (Denmark)

Vorstrup, S; Paulson, O B; Lassen, N A

1986-01-01

Serial measurements of cerebral blood flow (CBF) were performed in 12 patients with acute symptoms of ischemic cerebrovascular disease. CBF was measured by xenon-133 inhalation and single photon emission computer tomography. Six patients had severe strokes and large infarcts on the CT scan...

Identification of proteins regulated by ferulic acid in a middle cerebral artery occlusion animal model-a proteomics approach.

Science.gov (United States)

Sung, Jin-Hee; Cho, Eun-Hae; Cho, Jae-Hyeon; Won, Chung-Kil; Kim, Myeong-Ok; Koh, Phil-Ok

2012-11-01

Ferulic acid plays a neuroprotective role in cerebral ischemia. The aim of this study was to identify the proteins that are differentially expressed following ferulic acid treatment during ischemic brain injury using a proteomics technique. Middle cerebral artery occlusion (MCAO) was performed to induce a focal cerebral ischemic injury in adult male rats, and ferulic acid (100 mg/kg) or vehicle was administered immediately after MCAO. Brain tissues were collected 24 hr after MCAO. The proteins in the cerebral cortex were separated using two-dimensional gel electrophoresis and were identified by mass spectrometry. We detected differentially expressed proteins between vehicle- and ferulic acid-treated animals. Adenosylhomocysteinase, isocitrate dehydrogenase [NAD(+)], mitogen-activated protein kinase kinase 1 and glyceraldehyde-3-phosphate dehydrogenase were decreased in the vehicle-treated group, and ferulic acid prevented the injury-induced decreases in these proteins. However, pyridoxal phosphate phosphatase and heat shock protein 60 were increased in the vehicle-treated group, while ferulic acid prevented the injury-induced increase in these proteins. It is accepted that these enzymes are involved in cellular metabolism and differentiation. Thus, these findings suggest evidence that ferulic acid plays a neuroprotective role against focal cerebral ischemia through the up- and down-modulation of specific enzymes.

Reduced cerebral ischemia-reperfusion injury in Toll-like receptor 4 deficient mice

International Nuclear Information System (INIS)

Cao Canxiang; Yang Qingwu; Lv Fenglin; Cui Jie; Fu Huabin; Wang Jingzhou

2007-01-01

Inflammatory reaction plays an important role in cerebral ischemia-reperfusion injury, however, its mechanism is still unclear. Our study aims to explore the function of Toll-like receptor 4 (TLR4) in the process of cerebral ischemia-reperfusion. We made middle cerebral artery ischemia-reperfusion model in mice with line embolism method. Compared with C3H/OuJ mice, scores of cerebral water content, cerebral infarct size and neurologic impairment in C3H/Hej mice were obviously lower after 6 h ischemia and 24 h reperfusion. Light microscopic and electron microscopic results showed that cerebral ischemia-reperfusion injury in C3H/Hej mice was less serious than that in C3H/OuJ mice. TNF-α and IL-6 contents in C3H/HeJ mice were obviously lower than that in C3H/OuJ mice with ELISA. The results showed that TLR4 participates in the process of cerebral ischemia-reperfusion injury probably through decrease of inflammatory cytokines. TLR4 may become a new target for prevention of cerebral ischemia-reperfusion injury. Our study suggests that TLR4 is one of the mechanisms of cerebral ischemia-reperfusion injury besides its important role in innate immunity

Deep cerebral microbleeds are negatively associated with HDL-C in elderly first-time ischemic stroke patients.

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Igase, Michiya; Kohara, Katsuhiko; Igase, Keiji; Yamashita, Shiro; Fujisawa, Mutsuo; Katagi, Ryosuke; Miki, Tetsuro

2013-02-15

Cerebral microbleeds (CMBs) detected on T2*-weighted MRI gradient-echo have been associated with increased risk of cerebral infarction. We evaluated risk factors for these lesions in a cohort of first-time ischemic stroke patients. Presence of CMBs in consecutive first-time ischemic stroke patients was evaluated. The location of CMBs was classified by cerebral region as strictly lobar (lobar CMBs) and deep or infratentorial (deep CMBs). Logistic regression analysis was performed to determine the contribution of lipid profile to the presence of CMBs. One hundred and sixteen patients with a mean age of 70±10years were recruited. CMBs were present in 74 patients. The deep CMBs group had significantly lower HDL-C levels than those without CMBs. In univariable analysis, advanced periventricular hyperintensity grade (PVH>2) and decreased HDL-C were significantly associated with the deep but not the lobar CMB group. On logistic regression analysis, HDL-C (beta=-0.06, p=0.002) and PVH grade >2 (beta=3.40, p=0.005) were independent determinants of deep CMBs. Low HDL-C may be a risk factor of deep CMBs, including advanced PVH status, in elderly patients with acute ischemic stroke. Management of HDL-C levels might be a therapeutic target for the prevention of recurrence of stroke. Copyright © 2012 Elsevier B.V. All rights reserved.

The permeability of puerarin loaded poly(butylcyanoacrylate) nanoparticles coated with polysorbate 80 on the blood-brain barrier and its protective effect against cerebral ischemia/reperfusion injury.

Science.gov (United States)

Zhao, Li-xia; Liu, An-chang; Yu, Shu-wen; Wang, Zeng-xin; Lin, Xiao-qian; Zhai, Guang-xi; Zhang, Qing-zhu

2013-01-01

Puerarin (PUE) is a good candidate for treating stroke, but its low concentration in brain after administration limits its curative efficacy. The aim of the present work was to design and characterize PUE loaded poly(butylcyanoacrylate) nanoparticles (PBCN) coated with polysorbate 80 (Ps 80), and to evaluate the effect of PBCN on the permeability of PUE across the blood-brain barrier (BBB) and the effect of PUE loaded PBCN on the cerebral ischemia/reperfusion injury. PUE loaded PBCN were successfully prepared by anionic polymerization method with the mean particle size of 201.2 nm and the zeta potential of -7.72 mV. The in vitro release behavior of PUE from the nanoparticles showed a biphasic profile manner with an initial burst release followed by a sustained release. The results of pharmacokinetic and biodistribution to brain performed in mice after intravenous administration showed that the drug concentrations in blood and brain for PUE loaded PBCN were both greater than these for the free drug. Moreover, compared with free drug, the vein injection of PUE loaded PBCN exerted the better neuroprotective effect in rats with focal cerebral ischemic injury via significantly decreasing neurological deficit scores, increasing body weight, lowing brain water content, and reducing the infarct volume. The results indicated that this preparation may reduce the total dose required for the stroke therapy with concurrent reduction in dose related toxicity. All these findings suggest that PBCN could enhance the transport of PUE to brain and have a potential as a neuroprotective agent in the focal cerebral ischemic injury.

Preferential cephalic redistribution of left ventricular cardiac output during therapeutic hypothermia for perinatal hypoxic-ischemic encephalopathy.

Science.gov (United States)

Hochwald, Ori; Jabr, Mohammad; Osiovich, Horacio; Miller, Steven P; McNamara, Patrick J; Lavoie, Pascal M

2014-05-01

To determine the relationship between left ventricular cardiac output (LVCO), superior vena cava (SVC) flow, and brain injury during whole-body therapeutic hypothermia. Sixteen newborns with moderate or severe hypoxic-ischemic encephalopathy were studied using echocardiography during and immediately after therapeutic hypothermia. Measures were also compared with 12 healthy newborns of similar postnatal age. Newborns undergoing therapeutic hypothermia also had cerebral magnetic resonance imaging as part of routine clinical care on postnatal day 3-4. LVCO was markedly reduced (mean ± SD 126 ± 38 mL/kg/min) during therapeutic hypothermia, whereas SVC flow was maintained within expected normal values (88 ± 27 mL/kg/min) such that SVC flow represented 70% of the LVCO. The reduction in LVCO during therapeutic hypothermia was mainly accounted by a reduction in heart rate (99 ± 13 vs 123 ± 17 beats/min; P newborns without brain injury (P = .013). Newborns with perinatal hypoxic-ischemic encephalopathy showed a preferential systemic-to-cerebral redistribution of cardiac blood flow during whole-body therapeutic hypothermia, which may reflect a lack of cerebral vascular adaptation in newborns with more severe brain injury. Copyright © 2014 Elsevier Inc. All rights reserved.

Pathways to ischemic neuronal cell death: are sex differences relevant?

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McCullough Louise D

2008-06-01

Full Text Available Abstract We have known for some time that the epidemiology of human stroke is sexually dimorphic until late in life, well beyond the years of reproductive senescence and menopause. Now, a new concept is emerging: the mechanisms and outcome of cerebral ischemic injury are influenced strongly by biological sex as well as the availability of sex steroids to the brain. The principal mammalian estrogen (17 β estradiol or E2 is neuroprotective in many types of brain injury and has been the major focus of investigation over the past several decades. However, it is becoming increasingly clear that although hormones are a major contributor to sex-specific outcomes, they do not fully account for sex-specific responses to cerebral ischemia. The purpose of this review is to highlight recent studies in cell culture and animal models that suggest that genetic sex determines experimental stroke outcome and that divergent cell death pathways are activated after an ischemic insult. These sex differences need to be identified if we are to develop efficacious neuroprotective agents for use in stroke patients.

Anti neuroinflammatory effect of Vildagliptin in ischaemia-reperfusion induced cerebral infarction in normal and STZ induced type-II diabetic rats

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Kaleru Purnachander

2016-03-01

Full Text Available Diabetes is one of the major risk factor for cerebral ischemic stroke. Increased base line levels of oxidative stress in diabetes will lead to cerebral ischemic damage. In pathological conditions such as cerebral ischemia/reperfusion injury, free radicals cause oxidative stress and inflammation leading to increased injury of brain. Inflammation is one of the major pathological mechanisms involved in cerebral ischemia and reperfusion injury. Vildagliptin newer anti-diabetic drug of the class DPP-4 inhibitors is reported to have anti-inflammatory properties apart from its antihyperglycemic activity. Therefore the aim of the present study is to evaluate the anti-inflammatory effect of Vildagliptin against cerebral infarction induced ischemia reperfusion injury in normal and STZ induced diabetic Wistar rats. Cerebral infarction was induced by bilateral common carotid artery occlusion followed by 4 hr reperfusion. Percent infarction, inflammatory markers such as MPO, TNF-α, IL-6 and IL-10 were analysed. Treatment with Vildagliptin for a period of four weeks produced significant reduction in percent cerebral infarct volume. Vildagliptin at 10 mg/kg dose, showed significant reduction in markers like MPO, TNF-α, IL-6 and IL-1β in diabetic group when compared to normal group and in contrast significant increase in anti-inflammatory marker like IL-10 levels. Vildagliptin showed significant cerebroprotective effect by antiinflammatory mechanisms.

A Microarray Study of Middle Cerebral Occlusion Rat Brain with Acupuncture Intervention

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Chao Zhang

2015-01-01

Full Text Available Microarray analysis was used to investigate the changes of gene expression of ischemic stroke and acupuncture intervention in middle cerebral artery occlusion (MCAo rat brain. Results showed that acupuncture intervention had a remarkable improvement in neural deficit score, cerebral blood flow, and cerebral infarction volume of MCAo rats. Microarray analysis showed that a total of 627 different expression genes were regulated in ischemic stroke. 417 genes were upregulated and 210 genes were downregulated. A total of 361 different expression genes were regulated after acupuncture intervention. Three genes were upregulated and 358 genes were downregulated. The expression of novel genes after acupuncture intervention, including Tph1 and Olr883, was further analyzed by Real-Time Quantitative Polymerase Chain Reaction (RT-PCR. Upregulation of Tph1 and downregulation of Olr883 indicated that the therapeutic effect of acupuncture for ischemic stroke may be closely related to the suppression of poststroke depression and regulation of olfactory transduction. In conclusion, the present study may enrich our understanding of the multiple pathological process of ischemic brain injury and indicate possible mechanisms of acupuncture on ischemic stroke.

Repeated exposure to methamphetamine induces sex-dependent hypersensitivity to ischemic injury in the adult rat heart.

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Boyd R Rorabaugh

Full Text Available We previously reported that adult female, but not male rats that were prenatally exposed to methamphetamine exhibit myocardial hypersensitivity to ischemic injury. However, it is unknown whether hypersensitivity to ischemic injury develops when rats are exposed to methamphetamine during adulthood. The goal of this study was to determine whether methamphetamine exposure during adulthood sensitizes the heart to ischemic injury.Adult male and female rats received daily injections of methamphetamine (5 mg/kg or saline for 10 days. Their hearts were isolated on day 11 and subjected to a 20 min ischemic insult on a Langendorff isolated heart apparatus. Cardiac contractile function was measured by an intraventricular balloon, and infarct size was measured by triphenyltetrazolium chloride staining.Hearts from methamphetamine-treated females exhibited significantly larger infarcts and suppressed postischemic recovery of contractile function compared to hearts from saline-treated females. In contrast, methamphetamine had no effect on infarct size or contractile recovery in male hearts. Subsequent experiments demonstrated that hypersensitivity to ischemic injury persisted in female hearts following a 1 month period of abstinence from methamphetamine. Myocardial protein kinase C-ε expression, Akt phosphorylation, and ERK phosphorylation were unaffected by adult exposure to methamphetamine.Exposure of adult rats to methamphetamine sex-dependently increases the extent of myocardial injury following an ischemic insult. These data suggest that women who have a heart attack might be at risk of more extensive myocardial injury if they have a recent history of methamphetamine abuse.

Repeated exposure to methamphetamine induces sex-dependent hypersensitivity to ischemic injury in the adult rat heart

Science.gov (United States)

Seeley, Sarah L.; Stoops, Thorne S.; D’Souza, Manoranjan S.

2017-01-01

Background We previously reported that adult female, but not male rats that were prenatally exposed to methamphetamine exhibit myocardial hypersensitivity to ischemic injury. However, it is unknown whether hypersensitivity to ischemic injury develops when rats are exposed to methamphetamine during adulthood. The goal of this study was to determine whether methamphetamine exposure during adulthood sensitizes the heart to ischemic injury. Methods Adult male and female rats received daily injections of methamphetamine (5 mg/kg) or saline for 10 days. Their hearts were isolated on day 11 and subjected to a 20 min ischemic insult on a Langendorff isolated heart apparatus. Cardiac contractile function was measured by an intraventricular balloon, and infarct size was measured by triphenyltetrazolium chloride staining. Results Hearts from methamphetamine-treated females exhibited significantly larger infarcts and suppressed postischemic recovery of contractile function compared to hearts from saline-treated females. In contrast, methamphetamine had no effect on infarct size or contractile recovery in male hearts. Subsequent experiments demonstrated that hypersensitivity to ischemic injury persisted in female hearts following a 1 month period of abstinence from methamphetamine. Myocardial protein kinase C-ε expression, Akt phosphorylation, and ERK phosphorylation were unaffected by adult exposure to methamphetamine. Conclusions Exposure of adult rats to methamphetamine sex-dependently increases the extent of myocardial injury following an ischemic insult. These data suggest that women who have a heart attack might be at risk of more extensive myocardial injury if they have a recent history of methamphetamine abuse. PMID:28575091

Posterior Cerebral Infarction following Loss of Guide Wire

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Jean-Marc Bugnicourt

2013-01-01

Full Text Available Stroke after internal jugular venous cannulation typically leads to acute carotid or vertebral arteries injury and cerebral ischemia. We report the first case of delayed posterior cerebral infarction following loss of guide wire after left internal jugular venous cannulation in a 46-year-old woman with a history of inflammatory bowel disease. Our observation highlights that loss of an intravascular guide wire can be a cause of ischemic stroke in patients undergoing central venous catheterization.

Early Cerebral Hemodynamic, Metabolic, and Histological Changes in Hypoxic-Ischemic Fetal Lambs during Postnatal Life.

Science.gov (United States)

Rey-Santano, Carmen; Mielgo, Victoria E; Gastiasoro, Elena; Murgia, Xabier; Lafuente, Hector; Ruiz-Del-Yerro, Estibaliz; Valls-I-Soler, Adolf; Hilario, Enrique; Alvarez, Francisco J

2011-01-01

The hemodynamic, metabolic, and biochemical changes produced during the transition from fetal to neonatal life may be aggravated if an episode of asphyxia occurs during fetal life. The aim of the study was to examine regional cerebral blood flow (RCBF), histological changes, and cerebral brain metabolism in preterm lambs, and to analyze the role of oxidative stress in the first hours of postnatal life following severe fetal asphyxia. Eighteen chronically instrumented newborn lambs were randomly assigned to either a control group or the hypoxic-ischemic (HI) group, in which case fetal asphyxia was induced just before delivery. All the animals were maintained on intermittent positive pressure ventilation for 3 h after delivery. During the HI insult, the injured group developed acidosis, hypoxia, hypercapnia, lactic acidosis, and tachycardia (relative to the control group), without hypotension. The intermittent positive pressure ventilation transiently improved gas exchange and cardiovascular parameters. After HI injury and during ventilatory support, there continued to be an increased RCBF in inner regions among the HI group, but no significant differences were detected in cortical flow compared to the control group. Also, the magnitude of the increase in TUNEL positive cells (apoptosis) and antioxidant enzymes, and decrease of ATP reserves was significantly greater in the brain regions where the RCBF was not higher. In conclusion, our findings identify early metabolic, histological, and hemodynamic changes involved in brain damage in premature asphyxiated lambs. Such changes have been described in human neonates, so our model could be useful to test the safety and the effectiveness of different neuroprotective or ventilation strategies applied in the first hours after fetal HI injury.

Cerebral blood flow in acute and chronic ischemic stroke using xenon-133 inhalation tomography

DEFF Research Database (Denmark)

Vorstrup, S; Paulson, O B; Lassen, N A

1986-01-01

. They showed in the acute phase (Days 1-3) very large low-flow areas, larger than the hypodense areas seen on the CT scan. The cerebral vasoconstrictor and vasodilator capacity was tested in the acute phase following aminophylline and acetazolamide, respectively. A preserved but reduced reactivity was seen......Serial measurements of cerebral blood flow (CBF) were performed in 12 patients with acute symptoms of ischemic cerebrovascular disease. CBF was measured by xenon-133 inhalation and single photon emission computer tomography. Six patients had severe strokes and large infarcts on the CT scan...

Hemopexin induces neuroprotection in the rat subjected to focal cerebral ischemia.

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Dong, Beibei; Cai, Min; Fang, Zongping; Wei, Haidong; Zhu, Fangyun; Li, Guochao; Dong, Hailong; Xiong, Lize

2013-06-10

The plasma protein hemopexin (HPX) exhibits the highest binding affinity to free heme. In vitro experiments and gene-knock out technique have suggested that HPX may have a neuroprotective effect. However, the expression of HPX in the brain was not well elucidated and its expression after cerebral ischemia-reperfusion injury was also poorly studied. Furthermore, no in vivo data were available on the effect of HPX given centrally on the prognosis of focal cerebral ischemia. In the present study, we systematically investigated expression of HPX in normal rat brain by immunofluorescent staining. The results showed that HPX was mainly expressed in vascular system and neurons, as well as in a small portion of astrocytes adjacent to the vessels in normal rat brain. Further, we determined the role of HPX in the process of focal cerebral ischemic injury and explored the effects of HPX treatment in a rat model of transient focal cerebral ischemia. After 2 h' middle cerebral artery occlusion (MCAO) followed by 24 h' reperfusion, the expression of HPX was increased in the neurons and astrocytes in the penumbra area, as demonstrated by immunohistochemistry and Western blot techniques. Intracerebroventricular injection of HPX at the onset of reperfusion dose-dependently reduced the infarct volumes and improved measurements of neurological function of the rat subjected to transient focal cerebral ischemia. The neuroprotective effects of HPX sustained for up to 7 days after experiments. Our study provides a new insight into the potential neuroprotective role of HPX as a contributing factor of endogenous protective mechanisms against focal cerebral ischemia injury, and HPX might be developed as a potential agent for treatment of ischemic stroke.

Hemodialysis Induces an Acute Decline in Cerebral Blood Flow in Elderly Patients

NARCIS (Netherlands)

Polinder-Bos, Harmke; Vállez García, David; Kuipers, Johanna; Elting, Jan Willem J.; Aries, M.J.H.; Krijnen, Wim P.; Groen, Hendrik; Willemsen, Antoon; van Laar, Peter; Strijkert, Fijanne; Luurtsema, Geert; Slart, Riemer; Westerhuis, Ralf; Gansevoort, Ron T.; Gaillard, Carlo A.; Franssen, Casper

The initiation of hemodialysis is associated with an accelerated decline of cognitive function and an increased incidence of cerebrovascular accidents and white matter lesions. Investigators have hypothesized that the repetitive circulatory stress of hemodialysis induces ischemic cerebral injury,

Acute stress decreases but chronic stress increases myocardial sensitivity to ischemic injury in rodents

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Eric D Eisenmann

2016-04-01

Full Text Available Cardiovascular disease is the largest cause of mortality worldwide, and stress is a significant contributor to the development of cardiovascular disease. The relationship between acute and chronic stress and cardiovascular disease is well-evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia-reperfusion injury. Conversely, chronic stress is arrythmogenic and increases sensitivity to myocardial ischemia-reperfusion injury. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions.

Neuroprotective effect of TAT-14-3-3ε fusion protein against cerebral ischemia/reperfusion injury in rats.

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Yuanjun Zhu

Full Text Available Stroke is the major cause of death and disability worldwide, and the thrombolytic therapy currently available was unsatisfactory. 14-3-3ε is a well characterized member of 14-3-3 family, and has been reported to protect neurons against apoptosis in cerebral ischemia. However, it cannot transverse blood brain barrier (BBB due to its large size. A protein transduction domain (PTD of HIV TAT protein, is capable of delivering a large variety of proteins into the brain. In this study, we generated a fusion protein TAT-14-3-3ε, and evaluated its potential neuroprotective effect in rat focal ischemia/reperfusion (I/R model. Western blot analysis validated the efficient transduction of TAT-14-3-3ε fusion protein into brain via a route of intravenous injection. TAT-14-3-3ε pre-treatment 2 h before ischemia significantly reduced cerebral infarction volume and improved neurologic score, while post-treatment 2 h after ischemia was less effective. Importantly, pre- or post-ischemic treatment with TAT-14-3-3ε significantly increased the number of surviving neurons as determined by Nissl staining, and attenuated I/R-induced neuronal apoptosis as showed by the decrease in apoptotic cell numbers and the inhibition of caspase-3 activity. Moreover, the introduction of 14-3-3ε into brain by TAT-mediated delivering reduced the formation of autophagosome, attenuated LC3B-II upregulation and reversed p62 downregulation induced by ischemic injury. Such inhibition of autophagy was reversed by treatment with an autophagy inducer rapamycin (RAP, which also attenuated the neuroprotective effect of TAT-14-3-3ε. Conversely, autophagy inhibitor 3-methyladenine (3-MA inhibited I/R-induced the increase in autophagic activity, and attenuated I/R-induced brain infarct. These results suggest that TAT-14-3-3ε can be efficiently transduced into brain and exert significantly protective effect against brain ischemic injury through inhibiting neuronal apoptosis and autophagic

Cytosolic phospholipase A2 alpha amplifies early cyclooxygenase-2 expression, oxidative stress and MAP kinase phosphorylation after cerebral ischemia in mice

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Koehler Raymond C

2010-07-01

Full Text Available Abstract Background The enzyme cytosolic phospholipase A2 alpha (cPLA2α has been implicated in the progression of cerebral injury following ischemia and reperfusion. Previous studies in rodents suggest that cPLA2α enhances delayed injury extension and disruption of the blood brain barrier many hours after reperfusion. In this study we investigated the role of cPLA2α in early ischemic cerebral injury. Methods Middle cerebral artery occlusion (MCAO was performed on cPLA2α+/+ and cPLA2α-/- mice for 2 hours followed by 0, 2, or 6 hours of reperfusion. The levels of cPLA2α, cyclooxygenase-2, neuronal morphology and reactive oxygen species in the ischemic and contralateral hemispheres were evaluated by light and fluorescent microscopy. PGE2 content was compared between genotypes and hemispheres after MCAO and MCAO and 6 hours reperfusion. Regional cerebral blood flow was measured during MCAO and phosphorylation of relevant MAPKs in brain protein homogenates was measured by Western analysis after 6 hours of reperfusion. Results Neuronal cPLA2α protein increased by 2-fold immediately after MCAO and returned to pre-MCAO levels after 2 hours reperfusion. Neuronal cyclooxygenase-2 induction and PGE2 concentration were greater in cPLA2α+/+ compared to cPLA2α-/- ischemic cortex. Neuronal swelling in ischemic regions was significantly greater in the cPLA2α+/+ than in cPLA2α-/- brains (+/+: 2.2 ± 0.3 fold vs. -/-: 1.7 ± 0.4 fold increase; P 2α+/+ ischemic core than in cPLA2α-/- (+/+: 7.12 ± 1.2 fold vs. -/-: 3.1 ± 1.4 fold; P 2α+/+, but not cPLA2α-/-, had disruption of neuron morphology and decreased PGE2 content. Phosphorylation of the MAPKs-p38, ERK 1/2, and MEK 1/2-was significantly greater in cPLA2a+/+ than in cPLA2α-/- ischemic cortex 6 hours after reperfusion. Conclusions These results indicate that cPLA2α modulates the earliest molecular and injury responses after cerebral ischemia and have implications for the potential clinical

Momordica charantia polysaccharides could protect against cerebral ischemia/reperfusion injury through inhibiting oxidative stress mediated c-Jun N-terminal kinase 3 signaling pathway.

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Gong, Juanjuan; Sun, Fumou; Li, Yihang; Zhou, Xiaoling; Duan, Zhenzhen; Duan, Fugang; Zhao, Lei; Chen, Hansen; Qi, Suhua; Shen, Jiangang

2015-04-01

Momordica charantia (MC) is a medicinal plant for stroke treatment in Traditional Chinese Medicine, but its active compounds and molecular targets are unknown yet. M. charantia polysaccharide (MCP) is one of the important bioactive components in MC. In the present study, we tested the hypothesis that MCP has neuroprotective effects against cerebral ischemia/reperfusion injury through scavenging superoxide (O2(-)), nitric oxide (NO) and peroxynitrite (ONOO(-)) and inhibiting c-Jun N-terminal protein kinase (JNK3) signaling cascades. We conducted experiments with in vivo global and focal cerebral ischemia/reperfusion rat models and in vitro oxygen glucose deprivation (OGD) neural cells. The effects of MCP on apoptotic cell death and infarction volume, the bioactivities of scavenging O2(-), NO and ONOO(-), inhibiting lipid peroxidation and modulating JNK3 signaling pathway were investigated. Major results are summarized as below: (1) MCP dose-dependently attenuated apoptotic cell death in neural cells under OGD condition in vitro and reduced infarction volume in ischemic brains in vivo; (2) MCP had directing scavenging effects on NO, O2(-) and ONOO(-) and inhibited lipid peroxidation; (3) MCP inhibited the activations of JNK3/c-Jun/Fas-L and JNK3/cytochrome C/caspases-3 signaling cascades in ischemic brains in vivo. Taken together, we conclude that MCP could be a promising neuroprotective ingredient of M. charantia and its mechanisms could be at least in part attributed to its antioxidant activities and inhibiting JNK3 signaling cascades during cerebral ischemia/reperfusion injury. Copyright © 2014 Elsevier Ltd. All rights reserved.

Neuroprotective Role of Nerve Growth Factor in Hypoxic-Ischemic Brain Injury

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Antonio Chiaretti

2013-06-01

Full Text Available Hypoxic-ischemic brain injuries (HIBI in childhood are frequently associated with poor clinical and neurological outcome. Unfortunately, there is currently no effective therapy to restore neuronal loss and to determine substantial clinical improvement. Several neurotrophins, such as Nerve Growth Factor (NGF, Brain-Derived Neurotrophic Factor (BDNF, and Glial Derived Neurotrophic Factor (GDNF, play a key role in the development, differentiation, and survival of the neurons of the peripheral and central nervous system. Experimental animal studies demonstrated their neuroprotective role in HIBI, while only a few studies examined the neuroprotective mechanisms in patients with severe HIBI. We report two cases of children with HIBI and prolonged comatose state who showed a significant improvement after intraventricular NGF administration characterized by amelioration of electroencephalogram (EEG and cerebral perfusion at single-photon emission computed tomography (SPECT. The improvement in motor and cognitive functions of these children could be related to the neuroprotective role exerted by NGF in residual viable cholinergic neurons, leading to the restoration of neuronal networks in the damaged brain.

Cerebral ischemic lesions detected with diffusion-weighted magnetic resonance imaging after carotid artery stenting: Comparison of several anti-embolic protection devices.

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Taha, Mahmoud M; Maeda, Masayuki; Sakaida, Hiroshi; Kawaguchi, Kenji; Toma, Naoki; Yamamoto, Akitaka; Hirose, Tomofumi; Miura, Youichi; Fujimoto, Masashi; Matsushima, Satoshi; Taki, Waro

2009-09-01

Distal embolism is an important periprocedural technical complication with carotid angioplasty and carotid artery stenting (CAS). We evaluated the safety and efficacy of protection devices used during CAS by detecting new cerebral ischemic lesions using diffusion-weighted magnetic resonance imaging in 95 patients who underwent 98 CAS procedures: 34 using single PercuSurge GuardWire, 31 using double balloon protection, 15 using proximal flow reverse protection devices, 14 using Naviballoon, and 4 using filter anti-embolic devices. Diffusion-weighted imaging was performed preoperatively and postoperatively to evaluate the presence of any new embolic cerebral lesions. Postoperative diffusion-weighted imaging revealed 117 new ischemic lesions. Three patients had new ischemic stroke, two minor and one major, all ipsilateral to the treated carotid artery. The remaining patients had clinically silent ischemia. The incidence of new embolic lesions was lower using the proximal flow reverse protection device than with the double balloon protection (33% vs. 48.4%), but the volume of ipsilateral new ischemic lesions per patient was 136.6 mm(3) vs. 86.9 mm(3), respectively. Neuroprotection with Naviballoon yielded ipsilateral lesions of large volume (86.6 mm(3)) and higher number (5.7 lesions per patient) than using the filter anti-embolic device (34.8 mm(3) and 1 lesion per patient). New cerebral ischemic lesions after neuroprotected CAS are usually silent. The lower incidence of distal ischemia using proximal flow reverse and double balloon protection devices is limited by the larger volume and higher number of ischemic lesions.

Cerebral ischemic lesions detected with diffusion-weighted magnetic resonance imaging after carotid artery stenting. Comparison of several anti-embolic protection devices

International Nuclear Information System (INIS)

Taha, M.M.; Maeda, Masayuki; Sakaida, Hiroshi

2009-01-01

Distal embolism is an important periprocedural technical complication with carotid angioplasty and carotid artery stenting (CAS). We evaluated the safety and efficacy of protection devices used during CAS by detecting new cerebral ischemic lesions using diffusion-weighted magnetic resonance imaging in 95 patients who underwent 98 CAS procedures: 34 using single PercuSurge GuardWire, 31 using double balloon protection, 15 using proximal flow reverse protection devices, 14 using Naviballoon, and 4 using filter anti-embolic devices. Diffusion-weighted imaging was performed preoperatively and postoperatively to evaluate the presence of any new embolic cerebral lesions. Postoperative diffusion-weighted imaging revealed 117 new ischemic lesions. Three patients had new ischemic stroke, two minor and one major, all ipsilateral to the treated carotid artery. The remaining patients had clinically silent ischemia. The incidence of new embolic lesions was lower using the proximal flow reverse protection device than with the double balloon protection (33% vs. 48.4%), but the volume of ipsilateral new ischemic lesions per patient was 136.6 mm 3 vs. 86.9 mm 3 , respectively. Neuroprotection with Naviballoon yielded ipsilateral lesions of large volume (86.6 mm 3 ) and higher number (5.7 lesions per patient) than using the filter anti-embolic device (34.8 mm 3 and 1 lesion per patient). New cerebral ischemic lesions after neuroprotected CAS are usually silent. The lower incidence of distal ischemia using proximal flow reverse and double balloon protection devices is limited by the larger volume and higher number of ischemic lesions. (author)

Metformin promotes focal angiogenesis and neurogenesis in mice following middle cerebral artery occlusion.

Science.gov (United States)

Liu, Yanqun; Tang, Guanghui; Zhang, Zhijun; Wang, Yongting; Yang, Guo-Yuan

2014-09-05

Current studies demonstrated that metformin is not only a hypoglycemic drug, but also a neuro-protective agent. However, the effect of metformin during ischemic brain injury is unclear. The aim of the present study is to explore the effect of metformin during ischemic brain injury. Adult male CD1 mice underwent 90min transient middle cerebral artery occlusion. Metformin (200mg/kg) was given at the time of reperfusion daily until sacrifice. Results showed that metformin treatment significantly reduced ischemia-induced brain atrophy volume compared to the control (pcerebral artery occlusion, suggesting that metformin is a potential new drug for ischemic stroke therapy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Ischemic stroke in patient with existing congenital hypoplasia of the middle cerebral artery

International Nuclear Information System (INIS)

Manchev, I.; Manolova, T.; Manchev, L.

2015-01-01

Presented is a clinical case of a woman 29 years old with ischemic stroke (IS), which has developed abruptly in existing congenital hypoplasia and occlusion of the middle cerebral artery. There are no other well or less well documented risk factors for cerebrovascular disease. In family history noted that the father of the patient died suddenly at the age of 45 years from stroke, also without evidence of vascular disease. On magnetic resonance imaging (MRI) of the brain is found high signal zone in the left nucleus lentiformis. We discussed the possibilities for implementing conventional angiography and eventually surgical procedures unfortunately rejected due to the high risk to the patient. Key words: Ischemic Stroke. Magnetic Resonance Imaging. Hypoplasia

Wavelet coherence analysis of dynamic cerebral autoregulation in neonatal hypoxic–ischemic encephalopathy

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Fenghua Tian

2016-01-01

Full Text Available Cerebral autoregulation represents the physiological mechanisms that keep brain perfusion relatively constant in the face of changes in blood pressure and thus plays an essential role in normal brain function. This study assessed cerebral autoregulation in nine newborns with moderate-to-severe hypoxic–ischemic encephalopathy (HIE. These neonates received hypothermic therapy during the first 72 h of life while mean arterial pressure (MAP and cerebral tissue oxygenation saturation (SctO2 were continuously recorded. Wavelet coherence analysis, which is a time-frequency domain approach, was used to characterize the dynamic relationship between spontaneous oscillations in MAP and SctO2. Wavelet-based metrics of phase, coherence and gain were derived for quantitative evaluation of cerebral autoregulation. We found cerebral autoregulation in neonates with HIE was time-scale-dependent in nature. Specifically, the spontaneous changes in MAP and SctO2 had in-phase coherence at time scales of less than 80 min (<0.0002 Hz in frequency, whereas they showed anti-phase coherence at time scales of around 2.5 h (~0.0001 Hz in frequency. Both the in-phase and anti-phase coherence appeared to be related to worse clinical outcomes. These findings suggest the potential clinical use of wavelet coherence analysis to assess dynamic cerebral autoregulation in neonatal HIE during hypothermia.

Relative cerebral blood volume as a marker of durable tissue-at-risk viability in hyperacute ischemic stroke.

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Cortijo, Elisa; Calleja, Ana Isabel; García-Bermejo, Pablo; Mulero, Patricia; Pérez-Fernández, Santiago; Reyes, Javier; Muñoz, Ma Fe; Martínez-Galdámez, Mario; Arenillas, Juan Francisco

2014-01-01

Selection of best responders to reperfusion therapies could be aided by predicting the duration of tissue-at-risk viability, which may be dependant on collateral circulation status. We aimed to identify the best predictor of good collateral circulation among perfusion computed tomography (PCT) parameters in middle cerebral artery (MCA) ischemic stroke and to analyze how early MCA response to intravenous thrombolysis and PCT-derived markers of good collaterals interact to determine stroke outcome. We prospectively studied patients with acute MCA ischemic stroke treated with intravenous thrombolysis who underwent PCT before treatment showing a target mismatch profile. Collateral status was assessed using a PCT source image-based score. PCT maps were quantitatively analyzed. Cerebral blood volume (CBV), cerebral blood flow, and Tmax were calculated within the hypoperfused volume and in the equivalent region of unaffected hemisphere. Occluded MCAs were monitored by transcranial Duplex to assess early recanalization. Main outcome variables were brain hypodensity volume and modified Rankin scale score at day 90. One hundred patients with MCA ischemic stroke imaged by PCT received intravenous thrombolysis, and 68 met all inclusion criteria. A relative CBV (rCBV) >0.93 emerged as the only predictor of good collaterals (odds ratio, 12.6; 95% confidence interval, 2.9-55.9; P=0.001). Early MCA recanalization was associated with better long-term outcome and lower infarct volume in patients with rCBV<0.93, but not in patients with high rCBV. None of the patients with rCBV<0.93 achieved good outcome in absence of early recanalization. High rCBV was the strongest marker of good collaterals and may characterize durable tissue-at-risk viability in hyperacute MCA ischemic stroke.

3H-1,2-Dithiole-3-thione as a novel therapeutic agent for the treatment of ischemic stroke through Nrf2 defense pathway.

Science.gov (United States)

Kuo, Ping-Chang; Yu, I-Chen; Scofield, Barbara A; Brown, Dennis A; Curfman, Eric T; Paraiso, Hallel C; Chang, Fen-Lei; Yen, Jui-Hung

2017-05-01

Cerebral ischemic stroke accounts for more than 80% of all stroke cases. During cerebral ischemia, reactive oxygen species produced in brain tissue induce oxidative stress and inflammatory responses. D3T, the simplest compound of the cyclic, sulfur-containing dithiolethiones, is found in cruciferous vegetables and has been reported to induce antioxidant genes and glutathione biosynthesis through activation of Nrf2. In addition to antioxidant activity, D3T was also reported to possess anti-inflammatory effects. In this study, we evaluated the therapeutic potential of D3T for the treatment of ischemic stroke and investigated the mechanisms underlying the protective effects of D3T in ischemic stroke. Mice subjected to transient middle cerebral artery occlusion/reperfusion (tMCAO/R) were administered with vehicle or D3T to evaluate the effect of D3T in cerebral brain injury. We observed D3T reduced infarct size, decreased brain edema, lessened blood-brain barrier disruption, and ameliorated neurological deficits. Further investigation revealed D3T suppressed microglia (MG) activation and inhibited peripheral inflammatory immune cell infiltration of CNS in the ischemic brain. The protective effect of D3T in ischemic stroke is mediated through Nrf2 induction as D3T-attenuated brain injury was abolished in Nrf2 deficient mice subjected to tMCAO/R. In addition, in vitro results indicate the induction of Nrf2 by D3T is required for its suppressive effect on MG activation and cytokine production. In summary, we demonstrate for the first time that D3T confers protection against ischemic stroke, which is mediated through suppression of MG activation and inhibition of CNS peripheral cell infiltration, and that the protective effect of D3T in ischemic stroke is dependent on the activation of Nrf2. Copyright © 2017 Elsevier Inc. All rights reserved.

13-Methyltetradecanoic acid mitigates cerebral ischemia/reperfusion injury

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Juan Yu

2016-01-01

Full Text Available 13-Methyltetradecanoic acid can stabilize cell membrane and have anti-inflammatory, antioxidant and anti-apoptotic effects. Previous studies mainly focused on peripheral nerve injury, but seldom on the central nervous system. We investigated whether these properties of 13-methyltetradecanoic acid have a neuroprotective effect on focal cerebral ischemia/reperfusion injury, and detected the expression of basic fibroblast growth factor and vascular endothelial growth factor. This study established rat models of middle cerebral artery occlusion/reperfusion injury by ischemia for 2 hours and reperfusion for 24 hours. At the beginning of reperfusion, 13-methyltetradecanoic acid 10, 40 or 80 mg/kg was injected into the tail vein. Results found that various doses of 13-methyltetradecanoic acid effectively reduced infarct volume, mitigate cerebral edema, and increased the mRNA and protein expression of basic fibroblast growth factor and vascular endothelial growth factor at 24 hours of reperfusion. The effect was most significant in the 13-methyltetradecanoic acid 40 and 80 mg/kg groups. The findings suggest that 13-methyltetradecanoic acid can relieve focal ischemia/reperfusion injury immediately after reperfusion, stimulate the upregulation of basic fibroblast growth factor and vascular endothelial growth factor to exert neuroprotective effects.

Conditioning techniques and ischemic reperfusion injury in relation to on-pump cardiac surgery

DEFF Research Database (Denmark)

Holmberg, Fredrik Eric Olof; Ottas, Konstantin Alex; Andreasen, Charlotte

2014-01-01

OBJECTIVES: The objective was to investigate the potential protective effects of two conditioning methods, on myocardial ischemic and reperfusion injury in relation to cardiac surgery. DESIGN: Totally 68 patients were randomly assigned to either a control group (n = 23), a remote ischemic...

Nutrition for brain recovery after ischemic stroke: an added value to rehabilitation.

Science.gov (United States)

Aquilani, Roberto; Sessarego, Paolo; Iadarola, Paolo; Barbieri, Annalisa; Boschi, Federica

2011-06-01

In patients who undergo rehabilitation after ischemic stroke, nutrition strategies are adopted to provide tube-fed individuals with adequate nutrition and/or to avoid the body wasting responsible for poor functional outcome and prolonged stay in the hospital. Investigations have documented that nutrition interventions can enhance the recovery of neurocognitive function in individuals with ischemic stroke. Experimental studies have shown that protein synthesis is suppressed in the ischemic penumbra. In clinical studies on rehabilitation patients designed to study the effects of counteracting or limiting this reduction of protein synthesis by providing protein supplementation, patients receiving such supplementation had enhanced recovery of neurocognitive function. Cellular damage in cerebral ischemia is also partly caused by oxidative damage secondary to free radical formation and lipid peroxidation. Increased oxidative stress negatively affects a patient's life and functional prognosis. Some studies have documented that nutrition supplementation with B-group vitamins may mitigate oxidative damage after acute ischemic stroke. Experimental investigations have also shown that cerebral ischemia changes synaptic zinc release and that acute ischemia increases zinc release, aggravating neuronal injury. In clinical practice, patients with ischemic stroke were found to have a lower than recommended dietary intake of zinc. Patients in whom daily zinc intake was normalized had better recovery of neurological deficits than subjects given a placebo. The aim of this review is to highlight those brain metabolic alterations susceptible to nutrition correction in clinical practice. The mechanisms underlying the relationship between cerebral ischemia and nutrition metabolic conditions are discussed.

Discussion on the treatment of cerebral ischemia-reperfusion injuries following intra-arterial thrombolysis

International Nuclear Information System (INIS)

Tian Hong; Song Chuan; Fan Ruxiong; Zhou Huchuan; Zhang Yubo; Zang Qiaoli; Zhang Yunquan; Liu Lei

2011-01-01

Objective: To investigate the therapeutic method of cerebral ischemia-reperfusion injuries occurred after arterial thrombolytic therapy for acute cerebral infarction. Methods: Thirty-five patients, encountered in authors' Department since Oct. 2005, with cerebral ischemia-reperfusion injuries, which occurred after thrombolytic therapy by using arterial perfusion of urokinase for acute cerebral infarction, were enrolled in this study. The clinical data were retrospectively analyzed. Results: After the thrombolytic therapy, completer or partial recanalization of the occluded cerebral arteries was obtained in 33 cases, while secondary cerebral hemorrhage occurred in 13 cases, of whom cerebral parenchyma bleeding was seen in 2 and hemorrhagic infarction in 11. Different degrees of cerebral edema were found in all 33 cases. Among them significant shift of the midline structures was detected in 18 (54.5%), which was manifested clinically as the worsening of disturbance of consciousness. Strict control of blood pressure, prompt adjustment of dehydration medication, strengthening the cerebral protection measures, cerebral decompression by fenestration, etc. were carried out. All the patients took a turn for the better and were out of danger with remarkable improvement of neurological functions except one patient who died from massive intracerebral hemorrhage. Conclusion: Usually, different degrees of reperfusion injuries will develop after thrombolytic therapy for cerebral arterial infarction. Strictly controlling blood pressure, promptly adjusting dehydration medication and strengthening cerebral protection are the keys to reduce the severity of cerebral reperfusion injuries. (authors)

Protective effect of grifolin against brain injury in an acute cerebral ...

African Journals Online (AJOL)

levels in tissue homogenates of the cerebral ischemic rats compared with those in the negative control ... (NO) in LPS-stimulated RAW 264.7 cells [10]. ... experimentation and animal use [13]. .... decrease in the percentage of tailed cells in the.

Neuroprotective effect of curcumin on transient focal cerebral ischemia in rats.

Science.gov (United States)

Zhao, Jing; Zhao, Yong; Zheng, Weiping; Lu, Yuyu; Feng, Gang; Yu, Shanshan

2008-09-10

Curcumin, a member of the curcuminoid family of compounds, is a yellow colored phenolic pigment obtained from the powdered rhizome of C. longa Linn. Recent studies have demonstrated that curcumin has protective effects against cerebral ischemia/reperfusion injury. However, little is known about its mechanism. Hence, in the present study the neuroprotective potential of curcumin was investigated in middle cerebral artery occlusion (MCAO) induced focal cerebral IR injury. Administration of curcumin 100 and 300 mg/kg i.p. 60 min after MCAO significantly diminished infarct volume, and improved neurological deficit in a dose-dependent manner. Nissl staining showed that the neuronal injury was significantly improved after being treated with curcumin. Curcumin significantly decreased the expression of caspase-3 protein. A higher number of TUNEL-positive cells were found in the vehicle group, but they were significantly decreased in the treated group. Taken together, these results suggest that the neuroprotective potentials of curcumin against focal cerebral ischemic injury are, at least in part, ascribed to its anti-apoptotic effects.

Neuroprotective actions of taurine on hypoxic-ischemic brain damage in neonatal rats.

Science.gov (United States)

Zhu, Xiao-Yun; Ma, Peng-Sheng; Wu, Wei; Zhou, Ru; Hao, Yin-Ju; Niu, Yang; Sun, Tao; Li, Yu-Xiang; Yu, Jian-Qiang

2016-06-01

Taurine is an abundant amino acid in the nervous system, which has been proved to possess antioxidation, osmoregulation and membrane stabilization. Previously it has been demonstrated that taurine exerts ischemic brain injury protective effect. This study was designed to investigate whether the protective effect of taurine has the possibility to be applied to treat neonatal hypoxic-ischemic brain damage. Seven-day-old Sprague-Dawley rats were treated with left carotid artery ligation followed by exposure to 8% oxygen to generate the experimental group. The cerebral damage area was measured after taurine post-treatment with 2,3,5-triphenyltetrazolium chloride (TTC) staining, Hematoxyline-Eosin (HE) staining and Nissl staining. The activities of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), total antioxidant capacity (T-AOC), myeloperoxtidase (MPO), ATP and Lactic Acid productions were assayed with ipsilateral hemisphere homogenates. Western-blot and immunofluorescence assay were processed to detect the expressions of AIF, Cyt C, Bax, Bcl-2 in brain. We found that taurine significantly reduced brain infarct volume and ameliorated morphological injury obviously reversed the changes of SOD, MDA, GSH-Px, T-AOC, ATP, MPO, and Lactic Acid levels. Compared with hypoxic-ischemic group, it showed marked reduction of AIF, Cyt C and Bax expressions and increase of Bcl-2 after post-treatment. We conclude that taurine possesses an efficacious neuroprotective effect after cerebral hypoxic-ischemic damage in neonatal rats. Copyright © 2016 Elsevier Inc. All rights reserved.

Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents.

Science.gov (United States)

Eisenmann, Eric D; Rorabaugh, Boyd R; Zoladz, Phillip R

2016-01-01

Cardiovascular disease (CVD) is the largest cause of mortality worldwide, and stress is a significant contributor to the development of CVD. The relationship between acute and chronic stress and CVD is well evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia-reperfusion injury (IRI). Conversely, chronic stress is arrhythmogenic and increases sensitivity to myocardial IRI. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions.

Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents

Science.gov (United States)

Eisenmann, Eric D.; Rorabaugh, Boyd R.; Zoladz, Phillip R.

2016-01-01

Cardiovascular disease (CVD) is the largest cause of mortality worldwide, and stress is a significant contributor to the development of CVD. The relationship between acute and chronic stress and CVD is well evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia–reperfusion injury (IRI). Conversely, chronic stress is arrhythmogenic and increases sensitivity to myocardial IRI. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions. PMID:27199778

Embrella embolic deflection device for cerebral protection during transcatheter aortic valve replacement

NARCIS (Netherlands)

Samim, Mariam; Agostoni, Pierfrancesco; Hendrikse, Jeroen; Budde, Ricardo P J; Nijhoff, Freek; Kluin, Jolanda; Ramjankhan, Faiz; Doevendans, Pieter A.; Stella, Pieter R.

2015-01-01

AIMS: To compare the extent of cerebral ischemic injury after transcatheter aortic valve replacement (TAVR) with the use of an Embrella Embolic Deflector System versus unprotected TAVR. METHODS: Fifteen patients with severe symptomatic aortic stenosis underwent TAVR with use of the Embrella Embolic

Embrella embolic deflection device for cerebral protection during transcatheter aortic valve replacement

NARCIS (Netherlands)

Samim, Mariam; Agostoni, Pierfrancesco; Hendrikse, Jeroen; Budde, Ricardo P. J.; Nijhoff, Freek; Kluin, Jolanda; Ramjankhan, Faiz; Doevendans, Pieter A.; Stella, Pieter R.

2015-01-01

Aims: To compare the extent of cerebral ischemic injury after transcatheter aortic valve replacement (TAVR) with the use of an Embrella Embolic Deflector System versus unprotected TAVR. Methods: Fifteen patients with severe symptomatic aortic stenosis underwent TAVR with use of the Embrella Embolic

The long-term risk of malignant astrocytic tumors after structural brain injury--a nationwide cohort study

DEFF Research Database (Denmark)

Munch, Tina Noergaard; Gørtz, Sanne; Wohlfahrt, Jan

2015-01-01

% CI: 0.49-0.90) compared with no injury. The specific long-term risks by type of injury were: traumatic brain injury RR = 0.32 (95% CI: 0.10-0.75); cerebral ischemic infarction RR = 0.69 (95% CI: 0.47-0.96); and intracerebral hemorrhage RR = 1.39 (95% CI: 0.64-2.60). CONCLUSION: We found no evidence......BACKGROUND: Neoplastic transformation of damaged astrocytes has been proposed as a possible pathological mechanism behind malignant astrocytic tumors. This study investigated the association between structural brain injuries causing reactive astrogliosis and long-term risk for malignant astrocytic...... tumors. METHODS: The cohort consisted of all individuals living in Denmark between 1978 and 2011. The personal identification number assigned to all individuals allowed retrieval of diagnoses of traumatic brain injury, cerebral ischemic infarction, and intracerebral hemorrhage from the National Patient...

The role in thanatogenesis of generalized brain edema in ischemic cerebral infarction (computer-morphometric research

Directory of Open Access Journals (Sweden)

E. A. Dyadyk

2012-12-01

Full Text Available This work presents the results of computer-morphometric study of perivascular and pericellular free (oedematous spaces in brain cortex at death from the ischemic cerebral infarction and from reasons unconnected directly with cerebral pathology. It was revealed, that the mean area of perivascular spaces (vasogenic edema index at brain infarction in 13 times exceeds such at extracerebral pathology, and mean area of pericellular spaces (cytotoxic edema index – almost in 12 times, but also it substantially differs on the degree of variation (in 2,5 times higher, than area of perivascular spaces.

Prophylactic Edaravone Prevents Transient Hypoxic-Ischemic Brain Injury: Implications for Perioperative Neuroprotection.

Science.gov (United States)

Sun, Yu-Yo; Li, Yikun; Wali, Bushra; Li, Yuancheng; Lee, Jolly; Heinmiller, Andrew; Abe, Koji; Stein, Donald G; Mao, Hui; Sayeed, Iqbal; Kuan, Chia-Yi

2015-07-01

Hypoperfusion-induced thrombosis is an important mechanism for postsurgery stroke and cognitive decline, but there are no perioperative neuroprotectants to date. This study investigated whether prophylactic application of Edaravone, a free radical scavenger already used in treating ischemic stroke in Japan, can prevent infarct and cognitive deficits in a murine model of transient cerebral hypoxia-ischemia. Adult male C57BL/6 mice were subjected to transient hypoxic-ischemic (tHI) insult that consists of 30-minute occlusion of the unilateral common carotid artery and exposure to 7.5% oxygen. Edaravone or saline was prophylactically applied to compare their effects on cortical oxygen saturation, blood flow, coagulation, oxidative stress, metabolites, and learning-memory using methods that include photoacoustic imaging, laser speckle contrast imaging, solid-state NMR, and Morris water maze. The effects on infarct size by Edaravone application at different time points after tHI were also compared. Prophylactic administration of Edaravone (4.5 mg/kg×2, IP, 1 hour before and 1 hour after tHI) improved vascular reperfusion, oxygen saturation, and the maintenance of brain metabolites, reducing oxidative stress, thrombosis, white-matter injury, and learning impairment after tHI insult. Delayed Edaravone treatment after 3 h post-tHI became unable to reduce infarct size. Acute application of Edaravone may be a useful strategy to prevent postsurgery stroke and cognitive impairment, especially in patients with severe carotid stenosis. © 2015 American Heart Association, Inc.

Rehabilitation Outcomes: Ischemic versus Hemorrhagic Strokes

OpenAIRE

Perna, Robert; Temple, Jessica

2015-01-01

Background. Ischemic and hemorrhagic strokes have different pathophysiologies and possibly different long-term cerebral and functional implications. Hemorrhagic strokes expose the brain to irritating effects of blood and ischemic strokes reflect localized or diffuse cerebral vascular pathology. Methods. Participants were individuals who suffered either an ischemic (n = 172) or hemorrhagic stroke (n = 112) within the past six months and were involved in a postacute neurorehabilitation program....

Progressive Ischemic Stroke due to Thyroid Storm-Associated Cerebral Venous Thrombosis

Science.gov (United States)

Tanabe, Natsumi; Hiraoka, Eiji; Hoshino, Masataka; Deshpande, Gautam A.; Sawada, Kana; Norisue, Yasuhiro; Tsukuda, Jumpei; Suzuki, Toshihiko

2017-01-01

Patient: Female, 49 Final Diagnosis: Cerebral venous thrombosis Symptoms: Altered mental state • weakness in limbs Medication: — Clinical Procedure: — Specialty: Endocrinology and Metabolic Objective: Rare co-existance of disease or pathology Background: Cerebral venous thrombosis (CVT) is a rare but fatal complication of hyperthyroidism that is induced by the hypercoagulable state of thyrotoxicosis. Although it is frequently difficult to diagnose CVT promptly, it is important to consider it in the differential diagnosis when a hyperthyroid patient presents with atypical neurologic symptoms. Care Report: A 49-year-old Japanese female with unremarkable medical history came in with thyroid storm and multiple progressive ischemic stroke identified at another hospital. Treatment for thyroid storm with beta-blocker, glucocorticoid, and potassium iodide-iodine was started and MR venography was performed on hospital day 3 for further evaluation of her progressive ischemic stroke. The MRI showed CVT, and anticoagulation therapy, in addition to the anti-thyroid agents, was initiated. The patient’s thyroid function was successfully stabilized by hospital day 10 and further progression of CVT was prevented. Conclusions: Physicians should consider CVT when a patient presents with atypical course of stroke or with atypical MRI findings such as high intensity area in apparent diffusion coefficient (ADC) mapping. Not only is an early diagnosis and initiation of anticoagulation important, but identifying and treating the underlying disease is essential to avoid the progression of CVT. PMID:28228636

Hyperexpressed netrin-1promoted neural stem cells migration in mice after focal cerebral ischemia

OpenAIRE

Haiyan Lu; Xiaoyan Song; Feng Wang; Guodong Wang; Yuncheng Wu; Qiaoshu Wang; Yongting Wang; Guoyuan Yang; Zhijun Zhang

2016-01-01

Endogenous Netrin-1 (NT-1) protein was significantly increased after cerebral ischemia, which may participate in the repair after transient cerebral ischemic injury. In this work, we explored whether NT-1 can be steadily overexpressed by adeno-associated virus (AAV) and the exogenous NT-1 can promote neural stem cells migration from the subventricular zone (SVZ) region after cerebral ischemia. Adult CD-1 mice were injected stereotacticly with AAV carrying NT-1 gene (AAV-NT-1). Mice underwent ...

Computer assisted radionuclide angiography to confirm reversible ischemic cerebral dysfunction

International Nuclear Information System (INIS)

Buell, U.; Lanksch, W.; Tosch, U.; Kleinhans, E.; Steinhoff, H.

1982-01-01

Computer assisted radionuclide angiography (CARNA) was employed in patients with transient ischemic attack (TIA) or prolonged reversible ischemic neurologic deficit (PRIND) to establish the sensitivity of CARNA in detecting and quantifying changes of cerebral perfusion in such selected patients. Moreover, results of CARNA were compared with findings of cranial radiographic angiography (RGA) to obtain data on combined sensitivities of these methods. CARNA may be the preferred noninvasive procedure employed because it detects and quantifies the vascular supply disorder in patients with TIA and PRIND. If no computer assistance is used to evaluate cranial radionuclide angiography, results are considerable less accurate. Specifity of CARNA is 84.6%. If CARNA is negative (25.2% in TIA; 12.7% in PRIND), a further method must be employed to confirm the cranial vascular origin of the attack. This may be RGA in TIA and transmission computed axial tomography (T-CAT) T-CAT in PRIND. This diagnos - tic sequence lead to 92.4% true positive in TIA and to 93.2% true positives in PRIND

Regional cerebral blood flow in acute stage with ischemic cerebrovascular disease by xenon-133 inhalation and single photon emission computerized tomography

Energy Technology Data Exchange (ETDEWEB)

Kurokawa, Hiroyuki; Iino, Katsuro; Kojima, Hisashi; Saito, Hitoshi; Suzuki, Mikio; Watanabe, Kazuo; Kato, Toshiro

1987-05-01

Single photon emission computed tomography (SPECT) with xenon-133 inhalation method was undertaken within 48 hr after the onset in 68 patients with ischemic cerebrovascular disease. The results for regional cerebral blood flow (rCBF) were compared with concurrently available computed tomography (CT) scans. In patients with cerebral infarction, SPECT detected ischemic lesions earlier than CT, with the detectability being 92 %. The area with a decreased blood flow, as seen on SPECT, was more extensive than the low density area on CT, with a concomitant decrease in blood flow in the contralateral cerebral hemisphere. Crossed cerebellar diaschisis was associated with stenosis of the internal carotid artery in 50 % (7/14), and with stenosis of the middle cerebral artery in 35 % (9/26). Abnormal SPECT findings were seen in 47 % (8/17) of the patients with transient ischemic attack (TIA). Five TIA patients had a decreased rCBF on SPECT, which was not provided by CT scans. On the contrary, small infarct lesions in the cerebral basal ganglia, as observed in 4 patients, was not detected by SPECT, but detected by CT. This may imply the limitations of SPECT in the detection of deep-seated lesions of the cerebrum. The results led to the conclusion that SPECT can be performed safely even in acute, seriously ill patients to know changes in rCBF because it is noninvasive and is capable of being repeated in a short time. (Namekawa, K.).

Serum uric acid levels and cerebral microbleeds in patients with acute ischemic stroke.

Directory of Open Access Journals (Sweden)

Wi-Sun Ryu

Full Text Available Unlike experimental studies indicating a neuroprotective property of uric acid, clinical studies have shown that elevated levels of uric acid are associated with a risk of ischemic stroke. However, the association of uric acid with cerebral hemorrhage has seldom been tested. We aimed to elucidate the association between uric acid and cerebral microbleeds (CMBs, a hemorrhage-prone cerebral microangiopathy. Seven hundred twenty-four patients with ischemic stroke who were consecutively admitted to our hospital were included in this study. We collected demographic, clinical, and laboratory data, including uric acid level, and examined the presence of CMBs using T2*-weighted gradient-echo MRI. We used logistic regression analysis to examine an independent association between uric acid and CMBs. Two-hundred twenty-six patients had CMBs (31.2%. After adjusting for possible confounders, elevated uric acid was independently associated with the presence of CMBs (the highest quartile vs. lowest quartile, adjusted odd ratio [OR], 1.98; 95% confidence interval [CI], 1.16-3.39. This association retained in patients with deep or infratentorial CMBs (with or without lobar CMBs but not among those with lobar CMBs. In addition, this association was robust among patients with hypertension (the highest quartile vs. lowest quartile, adjusted OR, 2.74; 95% CI, 1.43-5.24. In contrast, we did not find the association in patients without hypertension. We demonstrated that serum uric acid is independently associated with the presence of CMBs. In particular, the relation between uric acid and CMBs was robust in hypertensive patients.

Serum uric acid levels and cerebral microbleeds in patients with acute ischemic stroke.

Science.gov (United States)

Ryu, Wi-Sun; Kim, Chi Kyung; Kim, Beom Joon; Lee, Seung-Hoon

2013-01-01

Unlike experimental studies indicating a neuroprotective property of uric acid, clinical studies have shown that elevated levels of uric acid are associated with a risk of ischemic stroke. However, the association of uric acid with cerebral hemorrhage has seldom been tested. We aimed to elucidate the association between uric acid and cerebral microbleeds (CMBs), a hemorrhage-prone cerebral microangiopathy. Seven hundred twenty-four patients with ischemic stroke who were consecutively admitted to our hospital were included in this study. We collected demographic, clinical, and laboratory data, including uric acid level, and examined the presence of CMBs using T2*-weighted gradient-echo MRI. We used logistic regression analysis to examine an independent association between uric acid and CMBs. Two-hundred twenty-six patients had CMBs (31.2%). After adjusting for possible confounders, elevated uric acid was independently associated with the presence of CMBs (the highest quartile vs. lowest quartile, adjusted odd ratio [OR], 1.98; 95% confidence interval [CI], 1.16-3.39). This association retained in patients with deep or infratentorial CMBs (with or without lobar CMBs) but not among those with lobar CMBs. In addition, this association was robust among patients with hypertension (the highest quartile vs. lowest quartile, adjusted OR, 2.74; 95% CI, 1.43-5.24). In contrast, we did not find the association in patients without hypertension. We demonstrated that serum uric acid is independently associated with the presence of CMBs. In particular, the relation between uric acid and CMBs was robust in hypertensive patients.

Effect of Pre-nutrion of Flax Seed Oil (Linum Usitatissimum on the amount of Cerebral ischemic lesion and motor nerve disorders in animal model rat.

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SV Hosseini

2015-10-01

Full Text Available Background & aim: Stroke is the third death agent (factor in industrial countries after cardiovascular disease and cancer. With regard to high content of antioxidant materials in flax seed oil like &alpha-linolenic acid, lignan as well as phenolic combinations like secoisolarisirsinol (SDG, this study performed for studding relationship between of cerebral ischemic lesion and motor-nerve disorders in model of stroke in rat. Methods: in the study, 35 male mice from strain Wistar divided to 5 groups. The groups included control, sham and 3 experimental groups. They received doses 0.25, 0.5 and 0.75 ml/kg from flax seed oil orally. By gavage for 30 days two control and sham groups received aqua distillate (distil water. Two hours after the last gavaged dose, overly group with 7 pieces operated for measurement of the amount of cerebral lesion and motor-nerve disorders. (Middle Cerebral Artery Occlusion Model. Middle cerebral Artery Occlusion by the model resulted in local ischemic stroke in animal. Data analyzed by software SPSS, test ANOVA and disorders by test mann-Whitney. Findings: Average of records of motor-nerve disorders decreased significantly in group with dose 0.5 and 0.75 using flax seed oil (P<0.05. The amount of cerebral ischemic lesion in doses 0.5 and 0.75 than to control group is indicated meaning full different, but percent of the total cerebral lesion in control group in compared group with dose 0.25 is not indicated meaningful different. Percent of the amount of ischemic lesion in region penumbra in group 0.75 and 0.5 than to control group is indicated meaningful different, but percent of the amount of lesion in region penumbra in control group in compared region penumbra in group with dose 0.25 is not indicated meaning full different. Results: Findings of the study indicated that flax seed oil, particular in doses 0.5 and 0.75 resulted to decrease of the amount of cerebral ischemic lesion and decrease of motor-nerve disorders in

Use of Fluorescein Isothiocyanate-Inulin as a Marker for Intestinal Ischemic Injury.

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AlKukhun, Abedalrazaq; Caturegli, Giorgio; Munoz-Abraham, Armando Salim; Judeeba, Sami; Patron-Lozano, Roger; Morotti, Raffaella; Rodriguez-Davalos, Manuel I; Geibel, John P

2017-06-01

Intestinal ischemia is observed in conditions such as mesenteric ischemia, or during traumatic events such as intestinal transplantation. Intestinal ischemia leads to pathophysiologic disruptions that present as increased fluid secretion into the intestinal lumen. We propose a novel method to detect real-time ischemic injury that is used in an in vitro model applicable to intestinal transplantation. Small intestine segments from rats were procured. The segments were attached to customized perfusion chambers. Both intestines were perfused on the vascular side with a Ringer buffer solution. The experimental buffer solution was bubbled with 100% nitrogen to mimic ischemia. Both lumens were perfused with 3 mL HEPES-Ringer solution containing 50 μM fluorescein isothiocyanate (FITC)-inulin. Intraluminal samples were collected at 15-minute intervals to measure FITC-inulin concentration using a nanofluorospectrophotometer. Intestinal tissue samples were processed and evaluated by a blinded pathologist using the Park/Chiu scoring system for grading intestinal ischemia. Samples collected from the ischemic intestine showed a significant decrease in FITC-inulin fluorescence compared with the control intestine, indicating enhanced fluid secretion. Histopathologic samples from the experimental arm exhibited higher scores of ischemic injury in comparison with the control arm, confirming the FITC-inulin as a correlation to ischemia. Fluorescein isothiocyanate-inulin can be used as a real-time volume marker to monitor the ischemic state of intestinal tissue. A positive correlation between the degree of fluid shift and presence of ischemic injury. The changes in fluorescence signal provide a potential selective method to measure real-time fluid changes inside an intestinal graft to evaluate viability. Copyright © 2016 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

Demethylation of Circulating Estrogen Receptor Alpha Gene in Cerebral Ischemic Stroke.

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Hsiu-Fen Lin

Full Text Available Estrogen is involved in neuron plasticity and can promote neuronal survival in stroke. Its actions are mostly exerted via estrogen receptor alpha (ERα. Previous animal studies have shown that ERα is upregulated by DNA demethylation following ischemic injury. This study investigated the methylation levels in the ERα promoter in the peripheral blood of ischemic stroke patients.The study included 201 ischemic stroke patients, and 217 age- and sex-comparable healthy controls. The quantitative methylation level in the 14 CpG sites of the ERα promoter was measured by pyrosequencing in each participant. Multivariate regression model was used to adjust for stroke traditional risk factors. Stroke subtypes and sex-specific analysis were also conducted.The results demonstrated that the stroke cases had a lower ERα methylation level than controls in all 14 CpG sites, and site 13 and site 14 had significant adjusted p-values of 0.035 and 0.026, respectively. Stroke subtypes analysis showed that large-artery atherosclerosis and cardio-embolic subtypes had significantly lower methylation levels than the healthy controls at CpG site 5, site 9, site 12, site 13 and site 14 with adjusted p = 0.039, 0.009, 0.025, 0.046 and 0.027 respectively. However, the methylation level for the patients with small vessel subtype was not significant. We combined the methylation data from the above five sites for further sex-specific analysis. The results showed that the significant association only existed in women (adjusted p = 0.011, but not in men (adjusted p = 0.300.Female stroke cases have lower ERα methylation levels than those in the controls, especially in large-artery and cardio-embolic stroke subtypes. The study implies that women suffering from ischemic stroke of specific subtype may undergo different protective mechanisms to reduce the brain injury.

Cocktail treatment, a promising strategy to treat acute cerebral ischemic stroke?

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Li-jun Liang

2016-01-01

Full Text Available Up to now, over 1,000 experimental treatments found in cells and rodents have been difficult to translate to human ischemic stroke. Since ischemia and reperfusion, two separate stages of ischemic stroke, have different pathophysiological mechanisms leading to brain injury, a combination of protective agents targeting ischemia and reperfusion respectively may obtain substantially better results than a single agent. Normobaric hyperoxia (NBO has been shown to exhibit neuro- and vaso-protective effects by improving tissue oxygenation when it is given during ischemia, however the effect of NBO would diminish when the duration of ischemia and reperfusion was extended. Therefore, during reperfusion drug treatment targeting inflammation, oxidative stress and free radical scavenger would be a useful adjuvant to extend the therapeutic window of tissue plasminogen activator, the only United States Food and Drug Administration (FDA approved treatment for acute ischemic stroke. In this review, we discussed the neuro- and vaso-protective effects of NBO and recent finding of combining NBO with other drugs.

Experimental Model of Cerebral Hypoperfusion Produced Memory-learning Deficits, and Modifications in Gene Expression

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Rilda LEÓN

2015-01-01

Full Text Available Cerebral ischemia is a major cause of death, for this reason animal models of cerebral ischemia are widely used to study both the pathophysiology of ischemic phenomenon and the evaluation of possible therapeutic agents with protective or regenerative properties. The objectives of this study were to examine the presence of neuronal damage in different brain areas following the ischemic event, and assess consequences of such activities on the processes of memory and learning. The study group included an experimental group ischemic animals (30 rats with permanent bilateral occlusion of the carotids, and a control group. Was evaluated gene expression and inflammatory ischemic by qPCR techniques 24h post injury, brain tissue morphology in areas of cortex, striatum and hippocampus seven days post injury and processes of memory and learning, 12 days post injury. The morphological studies showed that the procedure induces death of cell populations in cortex, striatum and hippocampus, ischemia modified gfap gene expression and ho, il-6, il-17 and ifn-γ, which can be used as a marker of early ischemic process. Additionally, the ischemic injury caused spatial memory decline. This characterization gives us an experimental model to develop future studies on the pathophysiology of ischemic events and assessing therapeutic strategies. MODELO EXPERIMENTAL DE HIPOPERFUSIÓN CEREBRAL PRODUCE DÉFICIT DE LA MEMORIA Y APRENDIZAJE Y MODIFICACIONES EN LA EXPRESIÓN DE GENES. A escala mundial, la isquemia cerebral constituye una de las principales causas de muerte, por lo que los modelos animales de isquemia cerebral son extensamente usados tanto en el estudio de la pato-fisiología del fenómeno isquémico; como en la evaluación de agentes terapéuticos con posible efecto protector o regenerador.  Los objetivos de este estudio fueron examinar la presencia de daño neuronal en diferentes áreas cerebrales como consecuencia del evento isquémico; así como evaluar

Analysis of ischemic cerebral lesions using 3.0-T diffusion-weighted imaging and magnetic resonance angiography after revascularization surgery for ischemic disease.

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Murai, Yasuo; Mizunari, Takayuki; Takagi, Ryo; Amano, Yasuo; Mizumura, Sunao; Komaba, Yuichi; Okubo, Seiji; Kobayashi, Shiro; Teramoto, Akira

2013-07-01

Cerebral revascularization surgery (CRS) is increasingly recognized as an important component in the treatment of complex cerebral vascular disease and tumors. CRS requires that the incidence of perioperative neurological complications should be minimized, because CRS for ischemic disease is often not the goal of treatment, but rather a prophylactic surgery. CRS carries the risk of focal postoperative neurological deficits. Little has been established concerning mechanisms of post-CRS ischemia. We used 3.0-T diffusion-weighted magnetic resonance imaging (DWI) and magnetic resonance angiography (MRA) to analyze the incidence and mechanism of ischemic lesions. We studied the anterior circulation territory after 20 CRS procedures involving 33 vascular anastomosis procedures (13 double anastomoses and 7 single anastomoses) in 12 men and 8 women between June 2007 and October 2011. The operations included single or double superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis to treat internal carotid artery/MCA occlusions or severe MCA stenosis. A combined STA-MCA anastomosis and indirect bypass were performed for moyamoya disease. Postoperative DWI and MRA were obtained in all patients between 24 and 96 h after surgery to detect thromboembolism, hypoperfusion, or procedural ischemic complications and vasospasms of the donor STA. Follow-up DWI and MRA were carried out 1.8±0.6 days after CRS (range, 1-4 days). Temporary occlusion time for anastomoses averaged 18.9 min (range, 16-32 min). Asymptomatic new hyperintensities occurred in the ipsilateral hemisphere of 2 patients on postoperative DWI (10% patients/6.0% anastomoses), and 1 moyamoya patient (5.0% patients/3.0% anastomoses) developed a symptomatic hyperintensity in the ipsilateral occipital lobe in response to the operation. Two abnormal small (3.0-T DWI study of CRS and related clinical events. The incidence of symptomatic postoperative DWI abnormalities was restricted to 1 moyamoya patient

Remote ischaemic preconditioning and prevention of cerebral injury.

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Rehni, Ashish K; Shri, Richa; Singh, Manjeet

2007-03-01

Bilateral carotid artery occlusion of 10 min followed by reperfusion for 24 hr was employed in present study to produce ischaemia and reperfusion induced cerebral injury in mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Short-term memory was evaluated using elevated plus maze. Inclined beam walking test was employed to assess motor incoordination. Bilateral carotid artery occlusion followed by reperfusion produced cerebral infarction and impaired short-term memory, motor co-ordination and lateral push response. A preceding episode of mesenteric artery occlusion for 15 min and reperfusion of 15 min (remote mesenteric ischaemic preconditioning) prevented markedly ischaemia-reperfusion-induced cerebral injury measured in terms of infarct size, loss of short-term memory, motor coordination and lateral push response. Glibenclamide (5 mg/kg, iv) a KATP channel blocker and caffeine (7 mg/kg, iv) an adenosine receptor blocker attenuated the neuroprotective effect of remote mesenteric ischaemic preconditioning. It may be concluded that neuroprotective effect of remote mesenteric ischaemic preconditioning may be due to activation of adenosine receptors and consequent activation of KATP channels in mice.

Neurologic Injury and Cerebral Blood Flow In Single Ventricles Throughout Staged Surgical Reconstruction

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Fogel, Mark A.; Li, Christine; Elci, Okan U.; Pawlowski, Tom; Schwab, Peter J.; Wilson, Felice; Nicolson, Susan C.; Montenegro, Lisa M.; Diaz, Laura; Spray, Thomas L.; Gaynor, J William; Fuller, Stephanie; Mascio, Christopher; Keller, Marc S.; Harris, Matthew A.; Whitehead, Kevin K.; Bethel, Jim; Vossough, Arastoo; Licht, Daniel J.

2017-01-01

Background Single ventricle patients experience a high rate of brain injury and adverse neurodevelopmental outcome, however, the incidence of brain abnormalities throughout surgical reconstruction and its relationship with cerebral blood flow, oxygen delivery and carbon dioxide reactivity remains unknown. Methods Single ventricle patients were studied with MRI scans immediately prior to bidirectional Glenn (pre-BDG), prior to Fontan and then 3–9 months after Fontan reconstruction. Results One hundred and sixty eight consecutive subjects recruited into the project underwent 235 scans: 63 pre-BDG (mean age 4.8+1.7 months), 118 BDG (2.9+1.4 years) and 54 after Fontan (2.4+1.0 years). Non-acute ischemic white matter changes on T2 weighted imaging, focal tissue loss, and ventriculomegaly were all more commonly detected in BDG and Fontans compared to pre-BDG (P<0.05). BDG patients has significantly higher CBF than Fontan patients. The odds of discovering brain injury adjusting for surgical stage as well as 2 or more co-existing lesions within a patient all decreased (63–75% and 44% respectively) with increasing amount of cerebral blood flow (P<0.05). In general, there was no association of oxygen delivery (with the exception of ventriculomegaly in the BDG group) or carbon dioxide reactivity with neurological injury. Conclusion Significant brain abnormalities are commonly present in single ventricle patients and detection of these lesions increase as children progress through staged surgical reconstruction with multiple co-existing lesions more common earlier than later. In addition, this study demonstrated that BDG patients had greater CBF than Fontan patients and that there exists an inverse association of various indices of CBF with these brain lesions, however, CO2 reactivity, oxygen delivery (with one exception) were not associated with brain lesion development. PMID:28031423

Superselective intra-arterial fibrinolysis for acute cerebral ischemic infarct : usefulness of diffusion weighted MR imaging

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Byun, Woo Mok; Lee, Se Jin; Kim, Yong Sun; Han, Gun Soo; Bae, Won Kyong

1999-01-01

To evaluate the efficacy of superselective intra-arterial fibrinolysis for acute cerebral stroke and the usefulness of pre-and postfibrinolysis diffusion-weighted MRI (DWI). In 41 patients with acute ischemic stroke whose treatment involved intra-arterial fibrinolysis, the occlusion site, degree of recanalization, and clinical results were compared. In 12 patients, diffusion weighted MRI was performed before fibrinolysis, and eight of these also underwent diffusion-weighted MRI after fibrinolysis. Using diffusion-weighted MRI, neurological outcomes were compared with signal intensity ratio (SIR, or the average signal intensity within the region of interest divided by that in the contralateral, nonischemic, homologous region). Twenty patients showed complete recanalization, nine partial recanalization, and in twelve there was no recanalization. Fourteen patients (34%) improved neurologically. No relationship existed between occlusion sites, degree of recanalization, and clinical outcome. Among 12 patients who underwent DWI before fibrinolysis, complete recanalization was noted in eight. Neurological improvement was seen in four patients with low SIR( 1.7), neurological outcome was poor despite complete recanalization. Although superselective intra-arterial fibrinolysis for acute cerebral stroke is a good therapeutic method for recanalization, the clinical outcome can be disappointing. We therefore suggest that in cases of acute cerebral ischemic infaret, SIR-as seen on DWI-might be useful for predicting the benefits of recanalization. In such cases, further investigation of the use of DWI prior to fibrinolysis is therefore needed

Hydrogen sulfide intervention in focal cerebral ischemia/reperfusion injury in rats

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Xin-juan Li

2015-01-01

Full Text Available The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusion model in rats via the suture method. Ten minutes after middle cerebral artery occlusion, the animals were intraperitoneally injected with hydrogen sulfide donor compound sodium hydrosulfide. Immunofluorescence revealed that the immunoreactivity of P2X 7 in the cerebral cortex and hippocampal CA1 region in rats with cerebral ischemia/reperfusion injury decreased with hydrogen sulfide treatment. Furthermore, treatment of these rats with hydrogen sulfide significantly lowered mortality, the Longa neurological deficit scores, and infarct volume. These results indicate that hydrogen sulfide may be protective in rats with local cerebral ischemia/reperfusion injury by down-regulating the expression of P2X 7 receptors.

Arctigenin protects focal cerebral ischemia-reperfusion rats through inhibiting neuroinflammation.

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Fan, Tao; Jiang, Wei Long; Zhu, Jian; Feng Zhang, Yu

2012-01-01

Stroke is the third leading cause of death in industrialized countries and the most important cause of acquired adult disability. Many evidences suggest that inflammation accounts for the progression of cerebral ischemic injury. Arctigenin, a phenylpropanoid dibenzylbutyrolactone lignin isolated from certain plants, has shown anti-inflammatory activity against diabetes and Alzheimer's disease. In this study, we tested whether arctigenin can protect middle cerebral artery occluded (MCAO) rats. Male Sprague-Dawley rats were pretreated with arctigenin or vehicle for 7 d before being subjected to transient occlusion of middle cerebral artery and reperfusion. Rats were evaluated at 24 h after MCAO for neurological deficit scoring. Furthermore, the mechanism of the anti-inflammatory effect of arctigenin was investigated with a focus on inflammatory cells, proinflammatory cytokines, and transcriptional factors. Arctigenin significantly reduced cerebral infarction and improved neurological outcome. Arctigenin suppressed the activation of microglia and decreased the expression of interleukin (IL)- 1β and tumor necrosis factor (TNF)-α. These results revealed that arctigenin has a promising therapeutic effect in ischemic stroke treatment through an anti-inflammatory mechanism.

CT diagnosis of hypoxic ischemic encephalopathy

International Nuclear Information System (INIS)

Zhao Xiang; Ma Jiwei; Wu Lide

2004-01-01

Objective: To explore CT characteristics of hypoxic ischemic encephalopathy (HIE), and to improve the accuracy of CT diagnosis. Methods: 50 cases of neonatal asphyxia in perinatal period diagnosed as hypoxic ischemic encephalopathy by CT was analyzed. Results: The main manifestation of hypoxic ischemic encephalopathy is cerebral edema and intracranial hemorrhage. Focal or diffuse hypo-dense lesion and hyper-dense area in various location and morphology were seen on CT images. (1) Localized diffuse hypo-dense area in 1 or 2 cerebral lobe were found in 17 cases, and the lesions were localized in frontal lobe (n=6), in frontotemporal lobe (n=5), and in temporo-occipital lobe (n=6). (2) Hypo-density region involving more than three cerebral lobes were found in 18 cases, and abnormalities were found in frontotemporal and parietal lobe (n=8), accompanying with subarachnoid hemorrhage (n=2); in frontal, temporal and occipital lobe (n=6), in which cerebral hemorrhage was complicated (n=1); and in other cerebral lobe (n=4). (3) Diffuse low-density region in all cerebral lobe were found in 15 cases, in which subarachnoid hemorrhage was complicated in 4 cases, and ventricular hemorrhage was found in 2 case. Conclusion: CT imaging plays an important role in diagnosis of hypoxic ischemic encephalopathy and has shown its clinical value

Post traumatic brain perfusion SPECT analysis using reconstructed ROI maps of radioactive microsphere derived cerebral blood flow and statistical parametric mapping

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Gonzalez-Brito Manuel; Solano Juan; Sanchez Pablo; Georgiou Michael F; Capille Michael; McGoron Anthony J; Kuluz John W

2008-01-01

Abstract Background Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. Me...

Adoptive regulatory T-cell therapy preserves systemic immune homeostasis after cerebral ischemia.

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Li, Peiying; Mao, Leilei; Zhou, Guoqing; Leak, Rehana K; Sun, Bao-Liang; Chen, Jun; Hu, Xiaoming

2013-12-01

Cerebral ischemia has been shown to result in peripheral inflammatory responses followed by long-lasting immunosuppression. Our recent study demonstrated that intravenous delivery of regulatory T cells (Tregs) markedly protected against transient cerebral ischemia by suppressing neutrophil-derived matrix metallopeptidase 9 production in the periphery. However, the effect of Tregs on systemic inflammatory responses and immune status has not been fully characterized. Cerebral ischemia was induced by middle cerebral artery occlusion for 60 minutes in mice or 120 minutes in rats. Tregs were isolated from donor animals by CD4 and CD25 double selection and transferred intravenously to ischemic recipients at 2 hours after middle cerebral artery occlusion. Animals were euthanized on different days after reperfusion. The effects of Tregs on systemic inflammation and immune status were evaluated using flow cytometry, ELISAs, and immunohistochemistry. Systemic administration of purified Tregs raises functional Tregs in the blood and peripheral organs, including spleen and lymph nodes. These exogenous Tregs remain in the blood and peripheral organs for ≥12 days. Functionally, Treg adoptive transfer markedly inhibits middle cerebral artery occlusion-induced elevation of inflammatory cytokines (interleukin-6 and tumor necrosis factor α) in the blood. Furthermore, Treg treatment corrects long-term lymphopenia and improves cellular immune functions after ischemic brain injury. As a result, Treg-treated animals exhibit decreased bacterial loads in the blood during recovery from cerebral ischemic attack. Treg treatment did not exacerbate poststroke immunosuppression. On the contrary, Treg-treated animals displayed improved immune status after focal cerebral ischemia.

Optical spectroscopy for the detection of ischemic tissue injury

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Demos, Stavros [Livermore, CA; Fitzgerald, Jason [Sacramento, CA; Troppmann, Christoph [Sacramento, CA; Michalopoulou, Andromachi [Athens, GR

2009-09-08

An optical method and apparatus is utilized to quantify ischemic tissue and/or organ injury. Such a method and apparatus is non-invasive, non-traumatic, portable, and can make measurements in a matter of seconds. Moreover, such a method and apparatus can be realized through optical fiber probes, making it possible to take measurements of target organs deep within a patient's body. Such a technology provides a means of detecting and quantifying tissue injury in its early stages, before it is clinically apparent and before irreversible damage has occurred.

Aquaporin-4 inhibition mediates piroxicam-induced neuroprotection against focal cerebral ischemia/reperfusion injury in rodents.

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Bhattacharya, Pallab; Pandey, Anand Kumar; Paul, Sudip; Patnaik, Ranjana; Yavagal, Dileep R

2013-01-01

Aquaporin-4(AQP4) is an abundant water channel protein in brain that regulates water transport to maintain homeostasis. Cerebral edema resulting from AQP4 over expression is considered to be one of the major determinants for progressive neuronal insult during cerebral ischemia. Although, both upregulation and downregulation of AQP4 expression is associated with brain pathology, over expression of AQP4 is one of the chief contributors of water imbalance in brain during ischemic pathology. We have found that Piroxicam binds to AQP4 with optimal binding energy value. Thus, we hypothesized that Piroxicam is neuroprotective in the rodent cerebral ischemic model by mitigating cerebral edema via AQP4 regulation. Rats were treated with Piroxicam OR placebo at 30 min prior, 2 h post and 4 h post 60 minutes of MCAO followed by 24 hour reperfusion. Rats were evaluated for neurological deficits and motor function just before sacrifice. Brains were harvested for infarct size estimation, water content measurement, biochemical analysis, RT-PCR and western blot experiments. Piroxicam pretreatment thirty minutes prior to ischemia and four hour post reperfusion afforded neuroprotection as evident through significant reduction in cerebral infarct volume, improvement in motor behavior, neurological deficit and reduction in brain edema. Furthermore, ischemia induced surge in levels of nitrite and malondialdehyde were also found to be significantly reduced in ischemic brain regions in treated animals. This neuroprotection was found to be associated with inhibition of acid mediated rise in intracellular calcium levels and also downregulated AQP4 expression. Findings of the present study provide significant evidence that Piroxicam acts as a potent AQP4 regulator and renders neuroprotection in focal cerebral ischemia. Piroxicam could be clinically exploited for the treatment of brain stroke along with other anti-stroke therapeutics in future.

The Ubiquitin E3 Ligase TRAF6 Exacerbates Ischemic Stroke by Ubiquitinating and Activating Rac1.

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Li, Tao; Qin, Juan-Juan; Yang, Xia; Ji, Yan-Xiao; Guo, Fangliang; Cheng, Wen-Lin; Wu, Xiaolin; Gong, Fu-Han; Hong, Ying; Zhu, Xue-Yong; Gong, Jun; Wang, Zhihua; Huang, Zan; She, Zhi-Gang; Li, Hongliang

2017-12-13

Stroke is one of the leading causes of morbidity and mortality worldwide. Inflammation, oxidative stress, apoptosis, and excitotoxicity contribute to neuronal death during ischemic stroke; however, the mechanisms underlying these complicated pathophysiological processes remain to be fully elucidated. Here, we found that the expression of tumor necrosis factor receptor-associated factor 6 (TRAF6) was markedly increased after cerebral ischemia/reperfusion (I/R) in mice. TRAF6 ablation in male mice decreased the infarct volume and neurological deficit scores and decreased proinflammatory signaling, oxidative stress, and neuronal death after cerebral I/R, whereas transgenic overexpression of TRAF6 in male mice exhibited the opposite effects. Mechanistically, we demonstrated that TRAF6 induced Rac1 activation and consequently promoted I/R injury by directly binding and ubiquitinating Rac1. Either functionally mutating the TRAF6 ubiquitination site on Rac1 or inactivating Rac1 with a specific inhibitor reversed the deleterious effects of TRAF6 overexpression during I/R injury. In conclusion, our study demonstrated that TRAF6 is a key promoter of ischemic signaling cascades and neuronal death after cerebral I/R injury. Therefore, the TRAF6/Rac1 pathway might be a promising target to attenuate cerebral I/R injury. SIGNIFICANCE STATEMENT Stroke is one of the most severe and devastating neurological diseases globally. The complicated pathophysiological processes restrict the translation of potential therapeutic targets into medicine. Further elucidating the molecular mechanisms underlying cerebral ischemia/reperfusion injury may open a new window for pharmacological interventions to promote recovery from stroke. Our study revealed that ischemia-induced tumor necrosis factor receptor-associated factor 6 (TRAF6) upregulation binds and ubiquitinates Rac1 directly, which promotes neuron death through neuroinflammation and neuro-oxidative signals. Therefore, precisely targeting

Progesterone induces neuroprotection following reperfusion-promoted mitochondrial dysfunction after focal cerebral ischemia in rats.

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Andrabi, Syed Suhail; Parvez, Suhel; Tabassum, Heena

2017-06-01

Organelle damage and increases in mitochondrial permeabilization are key events in the development of cerebral ischemic tissue injury because they cause both modifications in ATP turnover and cellular apoptosis/necrosis. Early restoration of blood flow and improvement of mitochondrial function might reverse the situation and help in recovery following an onset of stroke. Mitochondria and related bioenergetic processes can be effectively used as pharmacological targets. Progesterone (P4), one of the promising neurosteroids, has been found to be neuroprotective in various models of neurological diseases, through a number of mechanisms. This influenced us to investigate the possible role of P4 in the mitochondria-mediated neuroprotective mechanism in an ischemic stroke model of rat. In this study, we have shown the positive effect of P4 administration on behavioral deficits and mitochondrial health in an ischemic stroke injury model of transient middle cerebral artery occlusion (tMCAO). After induction of tMCAO, the rats received an initial intraperitoneal injection of P4 (8 mg/kg body weight) or vehicle at 1 h post-occlusion followed by subcutaneous injections at 6, 12 and 18 h. Behavioral assessment for functional deficits included grip strength, motor coordination and gait analysis. Findings revealed a significant improvement with P4 treatment in tMCAO animals. Staining of isolated brain slices from P4-treated rats with 2,3,5-triphenyltetrazolium chloride (TTC) showed a reduction in the infarct area in comparison to the vehicle group, indicating the presence of an increased number of viable mitochondria. P4 treatment was also able to attenuate mitochondrial reactive oxygen species (ROS) production, as well as block the mitochondrial permeability transition pore (mPTP), in the tMCAO injury model. In addition, it was also able to ameliorate the altered mitochondrial membrane potential and respiration ratio in the ischemic animals, thereby suggesting that P4 has

Sex-dependent effects of sleep deprivation on myocardial sensitivity to ischemic injury.

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Zoladz, Phillip R; Krivenko, Anna; Eisenmann, Eric D; Bui, Albert D; Seeley, Sarah L; Fry, Megan E; Johnson, Brandon L; Rorabaugh, Boyd R

2016-01-01

Sleep deprivation is associated with increased risk of myocardial infarction. However, it is unknown whether the effects of sleep deprivation are limited to increasing the likelihood of experiencing a myocardial infarction or if sleep deprivation also increases the extent of myocardial injury. In this study, rats were deprived of paradoxical sleep for 96 h using the platform-over-water method. Control rats were subjected to the same condition except the control platform was large enough for the rats to sleep. Hearts from sleep deprived and control rats were subjected to 20 min ischemia on a Langendorff isolated heart system. Infarct size and post ischemic recovery of contractile function were unaffected by sleep deprivation in male hearts. In contrast, hearts from sleep-deprived females exhibited significantly larger infarcts than hearts from control females. Post ischemic recovery of rate pressure product and + dP/dT were significantly attenuated by sleep deprivation in female hearts, and post ischemic recovery of end diastolic pressure was significantly elevated in hearts from sleep deprived females compared to control females, indicating that post ischemic recovery of both systolic and diastolic function were worsened by sleep deprivation. These data provide evidence that sleep deprivation increases the extent of ischemia-induced injury in a sex-dependent manner.

Multiplex Brain Proteomic Analysis Revealed the Molecular Therapeutic Effects of Buyang Huanwu Decoction on Cerebral Ischemic Stroke Mice.

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Hong-Jhang Chen

Full Text Available Stroke is the second-leading cause of death worldwide, and tissue plasminogen activator (TPA is the only drug used for a limited group of stroke patients in the acute phase. Buyang Huanwu Decoction (BHD, a traditional Chinese medicine prescription, has long been used for improving neurological functional recovery in stroke. In this study, we characterized the therapeutic effect of TPA and BHD in a cerebral ischemia/reperfusion (CIR injury mouse model using multiplex proteomics approach. After the iTRAQ-based proteomics analysis, 1310 proteins were identified from the mouse brain with <1% false discovery rate. Among them, 877 quantitative proteins, 10.26% (90/877, 1.71% (15/877, and 2.62% (23/877 of the proteins was significantly changed in the CIR, BHD treatment, and TPA treatment, respectively. Functional categorization analysis showed that BHD treatment preserved the integrity of the blood-brain barrier (BBB (Alb, Fga, and Trf, suppressed excitotoxicity (Grm5, Gnai, and Gdi, and enhanced energy metabolism (Bdh, thereby revealing its multiple effects on ischemic stroke mice. Moreover, the neurogenesis marker doublecortin was upregulated, and the activity of glycogen synthase kinase 3 (GSK-3 and Tau was inhibited, which represented the neuroprotective effects. However, TPA treatment deteriorated BBB breakdown. This study highlights the potential of BHD in clinical applications for ischemic stroke.

Predictors of early infection in cerebral ischemic stroke.

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Ashour, Wmr; Al-Anwar, A D; Kamel, A E; Aidaros, M A

2016-01-01

Infection is the most common complication of stroke. To determine the risk factors and predictors of post-stroke infection (PSI), which developed within 7 days from the onset of acute ischemic stroke. The study included 60 ischemic stroke patients admitted in the Neurology Department of Zagazig University, Egypt, who were subdivided into: [Non Stroke Associated Infection group (nSAI); 30 patients having stroke without any criteria of infection within 7 days from the onset and Stroke Associated Infection group (SAI); 30 patients having stroke with respiratory tract infection (RTI) or urinary tract infection within 7 days], in addition to 30 healthy sex and age-matching subjects as control. All the patients had a detailed history taking, thorough clinical general and neurological examination, laboratory tests (Urine analysis & urine culture, blood sugar, lipid profile and serum tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-10), a chest radiography to assess RTI and brain computed tomography (CT) to exclude the hemorrhagic stroke and to confirm the ischemic stroke. SAI patients were found to be significantly older with higher baseline blood glucose level. Also the number of patients with tube feeding, lower conscious level, more stroke severity and more large size infarcts were significantly higher in SAI patients. There was a significant elevation in the IL-10, a significant decrease in the TNF-α and a significant decrease in the TNF-α/ IL-10 ratio, in the SAI group. The baseline serum level of IL-10 ≥ 14.5 pg/ ml and size of infarct area > 3.5 cm3 were found to be the independent predictors of PSI. Patients with older age, tube feeding, lower conscious level, worse baseline stroke severity, large cerebral infarcts in CT scan, and increased IL-10 serum level were more susceptible to infection. The baseline serum level of IL-10 ≥ 14.5 pg/ ml and the size of infarct area > 3.5 cm3 were the independent predictors of PSI.

Sulforaphane exerts neuroprotective effects via suppression of the inflammatory response in a rat model of focal cerebral ischemia.

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Ma, Li-Li; Xing, Guo-Ping; Yu, Yin; Liang, Hui; Yu, Tian-Xia; Zheng, Wei-Hong; Lai, Tian-Bao

2015-01-01

Inflammatory damage plays an important role in cerebral ischemic pathogenesis and may represent a promising target for treatment. Sulforaphane exerts protective effects in a rat model of focal cerebral ischemia/reperfusion injury by alleviating brain edema. However, the possible mechanisms of sulforaphane after cerebral ischemia/reperfusion injury have not been fully elucidated. Therefore, in the present study, we investigated the effect of sulforaphane on inflammatory reaction and the potential molecular mechanisms in cerebral ischemia rats. We found that sulforaphane significantly attenuated the blood-brain barrier (BBB) disruption; decreased the levels of pro-inflammatory cytokines tumor necrosis factor (TNF)-α and interleukin (IL)-1β; reduced the nitric oxide (NO) levels and inducible nitric oxide synthase (iNOS) activity; inhibited the expression of iNOS and cyclooxygenase-2 (COX-2). In addition, sulforaphane inhibits the expression of p-NF-κB p65 after focal cerebral ischemia-reperfusion injury. Taken together, our results suggest that sulforaphane suppresses the inflammatory response via inhibiting the NF-κB signaling pathway in a rat model of focal cerebral ischemia, and sulforaphane may be a potential therapeutic agent for the treatment of cerebral ischemia injury.

Endogenous protection derived from activin A/Smads transduction loop stimulated via ischemic injury in PC12 cells.

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Mang, Jing; Mei, Chun-Li; Wang, Jiao-Qi; Li, Zong-Shu; Chu, Ting-Ting; He, Jin-Ting; Xu, Zhong-Xin

2013-10-17

Activin A (ActA), a member of transforming growth factor-beta (TGF-b) super- family, affects many cellular processes, including ischemic stroke. Though the neuroprotective effects of exogenous ActA on oxygen-glucose deprivation (OGD) injury have already been reported by us, the endogenous role of ActA remains poorly understood. To further define the role and mechanism of endogenous ActA and its signaling in response to acute ischemic damage, we used an OGD model in PC12 cells to simulate ischemic injury on neurons in vitro. Cells were pre-treated by monoclonal antibody against activin receptor type IIA (ActRII-Ab). We found that ActRII-Ab augments ischemic injury in PC12 cells. Further, the extracellular secretion of ActA as well as phosphorylation of smad3 in PC12 cells was also up-regulated by OGD, but suppressed by ActRII-Ab. Taken together, our results show that ActRII-Ab may augment ischemic injury via blocking of transmembrane signal transduction of ActA, which confirmed the existence of endogenous neuroprotective effects derived from the ActA/Smads pathway. ActRIIA plays an important role in transferring neuronal protective signals inside. It is highly possible that ActA transmembrance signaling is a part of the positive feed-back loop for extracellular ActA secretion.

Endogenous Protection Derived from Activin A/Smads Transduction Loop Stimulated via Ischemic Injury in PC12 Cells

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Zhong-Xin Xu

2013-10-01

Full Text Available Activin A (ActA, a member of transforming growth factor-beta (TGF-b super- family, affects many cellular processes, including ischemic stroke. Though the neuroprotective effects of exogenous ActA on oxygen-glucose deprivation (OGD injury have already been reported by us, the endogenous role of ActA remains poorly understood. To further define the role and mechanism of endogenous ActA and its signaling in response to acute ischemic damage, we used an OGD model in PC12 cells to simulate ischemic injury on neurons in vitro. Cells were pre-treated by monoclonal antibody against activin receptor type IIA (ActRII-Ab. We found that ActRII-Ab augments ischemic injury in PC12 cells. Further, the extracellular secretion of ActA as well as phosphorylation of smad3 in PC12 cells was also up-regulated by OGD, but suppressed by ActRII-Ab. Taken together, our results show that ActRII-Ab may augment ischemic injury via blocking of transmembrane signal transduction of ActA, which confirmed the existence of endogenous neuroprotective effects derived from the ActA/Smads pathway. ActRIIA plays an important role in transferring neuronal protective signals inside. It is highly possible that ActA transmembrance signaling is a part of the positive feed-back loop for extracellular ActA secretion.

Rapid and long-term induction of effector immediate early genes (BDNF, Neuritin and Arc) in peri-infarct cortex and dentate gyrus after ischemic injury in rat brain

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Rickhag, Karl Mattias; Teilum, Maria; Wieloch, Tadeusz

2007-01-01

including cerebral cortex and hippocampus. Brain-derived neurotrophic factor (BDNF), Neuritin and Activity-regulated cytoskeleton-associated protein (Arc) belong to a subgroup of immediate early genes implicated in synaptic plasticity known as effector immediate early genes. Here, we investigated...... at 0-6 h of reperfusion for Neuritin and 0-12 h of reperfusion for Arc while BDNF was induced 0-9 h of reperfusion. Our study demonstrates a rapid and long-term activation of effector immediate early genes in distinct brain areas following ischemic injury in rat. Effector gene activation may be part...

Clinic-like animal model for causal-pathogenetical investigations of hypoxic-ischemic brain injuries. Combined application of the radioactive labelled microsphere method and Positron Emission Tomography. Kliniknahes Tiermodell fuer kausal-pathogenetische Untersuchungen hypoxisch-ischaemischer Hirnschaedigung. Kombinierter Einsatz von Mikrosphaeren-Methode und Positronen-Emissions-Tomographie

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Bauer, R.; Zwiener, U.; Bergmann, R. (Univ. Jena, Inst. fuer Pathologische Physiologie (Germany)); Manfrass, P.; Enghardt, W.; Fromm, W.D. (Zentralinstitut fuer Kernforschung, Bereich Festkoeper- und Kernphysik, Rossendorf (Germany)); Hoyer, D.; Guenther, K. (Leipzig Univ., Radiologische Klinik (Germany)); Schubert, H. (Univ. Jena, Tierexperimentelles Zentrum (Germany)); Beyer, R.; Beyer, G.J.; Steinbach, J.; Kretzschmer, M. (Zentralinstitut fuer Kernforschung, Bereich Radioaktive Isotope, Rossendorf (Germany))

1990-01-01

The complex nature of the pathogenesis in hypoxic-ischemic brain injuries equires the combined determination of the dynamics of main factors in these disturbing processes. The application of suitable methods for registration of such pathogenetic processes is shown in an adequate animal model for simulating the early hypoxic-ischemic brain injuries. That the radioactive labelled microsphere technique is suitable to comprehend quantitively the dynamics of the intracerebral redistribution of the circulating blood due to hypoxia/hypercapnia by simultaneous-multiple measuring of the regional cerebral blood flow. Therefore, at the first time an inadequate hypoxic-induced blood flow increase was shown in large parts of the forebrain in intrauterine growth retarded newborn piglets. For estimation of the regional cerebral glucose utilization in newborn piglets, the {sup 18}F-FDG Positron Emission Tomography is introduced. The measurements were carried out on a stationary high-density avalanche chamber (HIDAC) camera and yielded the fundamental application of this camera model for PET investigations also in the newborn brain due to the very good spatial resolution. (orig.).

Neuroprotective effect of gadolinium: a stretch-activated calcium channel blocker in mouse model of ischemia-reperfusion injury.

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Gulati, Puja; Muthuraman, Arunachalam; Jaggi, Amteshwar S; Singh, Nirmal

2013-03-01

The present study was designed to investigate the potential of gadolinium, a stretch-activated calcium channel blocker in ischemic reperfusion (I/R)-induced brain injury in mice. Bilateral carotid artery occlusion of 12 min followed by reperfusion for 24 h was given to induce cerebral injury in male Swiss mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was assessed using Morris water maze test and motor incoordination was evaluated using rota-rod, lateral push, and inclined beam walking tests. In addition, total calcium, thiobarbituric acid reactive substance (TBARS), reduced glutathione (GSH), and acetylcholinesterase (AChE) activity were also estimated in brain tissue. I/R injury produced a significant increase in cerebral infarct size. A significant loss of memory along with impairment of motor performance was also noted. Furthermore, I/R injury also produced a significant increase in levels of TBARS, total calcium, AChE activity, and a decrease in GSH levels. Pretreatment of gadolinium significantly attenuated I/R-induced infarct size, behavioral and biochemical changes. On the basis of the present findings, we can suggest that opening of stretch-activated calcium channel may play a critical role in ischemic reperfusion-induced brain injury and that gadolinium has neuroprotective potential in I/R-induced injury.

Regional cerebral blood flow in patients with transient ischemic attacks studied by Xenon-133 inhalation and emission tomography

DEFF Research Database (Denmark)

Vorstrup, S; Hemmingsen, R; Henriksen, L

1983-01-01

Cerebral blood flow CBF was studied in 14 patients with transient ischemic attacks TIA and arteriosclerotic neck vessel disease. CBF was measured by a rapidly rotating single photon emission computerized tomograph using Xenon-133 inhalation. This method yields images of 3 brain slices depicting CBF...... with no abnormality on the CT-scan. The abnormal blood flow pattern was found to be unchanged after clinically successful reconstructive vascular surgery. This suggests the presence of irreversible ischemic tissue damage without gross emollition (incomplete infarction). It is concluded, that TIAs are often harmful...... events, as no less than 9 of the 14 patients studied had evidence of complete and/or incomplete infarction. Thorough examination and rational therapy should be instituted as soon as possible to prevent further ischemic lesions....

Hyperglycemia decreases preoxiredoxin-2 expression in a middle cerebral artery occlusion model.

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Koh, Phil-Ok

2017-06-01

Diabetes is a major risk factor for stroke and is also associated with worsened outcomes following a stroke. Peroxiredoxin-2 exerts potent neuroprotective effects against oxidative stress. In the present study, we identified altered peroxiredoxin-2 expression in an ischemic stroke model under hyperglycemic conditions. Adult male rats were administrated streptozotocin (40 mg/kg) via intraperitoneal injection to induce diabetes. Middle cerebral artery occlusion (MCAO) was induced surgically 4 weeks after streptozotocin treatment and cerebral cortex tissues were isolated 24 hours after MCAO. Peroxiredoxin-2 expression was evaluated in the cerebral cortex of MCAO-operated animals using a proteomics approach, and was found to be decreased. In addition, the reduction in peroxiredoxin-2 levels was more severe in cerebral ischemia with diabetes compared to animals without diabetes. Reverse-transcriptase PCR and Western blot analyses confirmed the significantly reduced peroxiredoxin-2 expression in MCAO-operated animals under hyperglycemic conditions. It is an accepted fact that peroxiredoxin-2 has antioxidative activity against ischemic injury. Thus, the findings of this study suggest that a more severe reduction in peroxiredoxin-2 under hyperglycemic conditions leads to worsened brain damage during cerebral ischemia with diabetes.

Characterization of neuronal damage by iomazenil binding and cerebral blood flow in an ischemic rat model

International Nuclear Information System (INIS)

Toyama, Hiroshi; Takeuchi, Akira; Koga, Sukehiko; Matsumura, Kaname; Nakashima, Hiromichi; Takeda, Kan; Yoshida, Toshimichi; Ichise, Masanori

1998-01-01

I-123-iomazenil is a SPECT probe for central benzodiazepine receptors (BZR) which may reflect intact cortical neuron density after ischemic insults. We evaluated whether neuronal damage in rats could be characterized by iomazenil as compared with cerebral blood flow (CBF). Serial changes in I-125-iomazenil for BZR and I-123-IMP for CBF were analyzed after the unilateral middle cerebral artery occlusion in rats by using an in vivo dualtracer technique. Uptake ratios of affected to contralateral regions were calculated. The iomazenil as well as IMP were decreased in all regions except for the cerebellum (remote area). Both iomazenil and IMP increased over time except in the temporal region (ischemic core). The iomazenil uptake was higher than IMP except in the ischemic core between 1 and 3-4 wk when iomazenil was lower than IMP. Iomazenil showed a moderate decrease in the proximal and middle parietal regions (peri-infarct areas) at 3-4 wk. The triphenyl-tetrazolium-chloride (TTC) stain at 1 wk demonstrated unstained tissue in the temporal region indicating tissue necrosis. With hematoxylin-eosin (HE) stain at 1 wk, widespread neuronal necrosis with occasional intact neurons were found in the proximal parietal region, and isolated necrotic neurons were represented in the distal parietal region. Iomazenil correlated well with the neuron distribution and the finding of a discrepancy between iomazenil and IMP might be useful in evaluating the neuronal damage. (author)

Study of the influence and molecular mechanism of ticagrelor on cerebral ischemia reperfusion injury in rats

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Gui-Fa Chen

2017-06-01

Full Text Available Objective: To study the influence and molecular mechanism of ticagrelor on cerebral ischemia reperfusion injury in rats. Methods: SD rats were selected as experimental animals and divided into control group, model group, ticagrelor group and clopidogrel group, cerebral ischemic reperfusion injury models were made, then ticagrelor group were given intragastric administration of 150 mg ticagrelor, clopidogrel group were given intragastric administration of 90 mg clopidogrel. 1 week after intervention, the brain water content as well as the contents of oxidative stress molecules and inflammatory factors were measured. Results: Water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of model group were significantly higher than those of control group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly lower than those of control group; water content in brain, MDA, Ox-LDL, NFkB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of ticagrelor group and clopidogrel group were significantly lower than those of model group while SOD, GSH-Px and Prdx6 contents in brain tissue were significantly higher than those of model group; water content in brain, MDA, Ox-LDL, NF-kB, TNF-α, IL-1β and IL-6 contents in brain tissue as well as TNF-α, IL-1β and IL-6 contents in serum of ticagrelor group were significantly lower than those of clopidogrel group while SOD, GSHPx and Prdx6 contents in brain tissue were significantly higher than those of clopidogrel group. Conclusion: Ticagrelor can be more effective in inhibiting oxidative stress response and inflammatory response, and reducing the cerebral ischemia reperfusion injury than clopidogrel.

A quantitative spatiotemporal analysis of microglia morphology during ischemic stroke and reperfusion

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Morrison Helena W

2013-01-01

Full Text Available Abstract Background Microglia cells continuously survey the healthy brain in a ramified morphology and, in response to injury, undergo progressive morphological and functional changes that encompass microglia activation. Although ideally positioned for immediate response to ischemic stroke (IS and reperfusion, their progressive morphological transformation into activated cells has not been quantified. In addition, it is not well understood if diverse microglia morphologies correlate to diverse microglia functions. As such, the dichotomous nature of these cells continues to confound our understanding of microglia-mediated injury after IS and reperfusion. The purpose of this study was to quantitatively characterize the spatiotemporal pattern of microglia morphology during the evolution of cerebral injury after IS and reperfusion. Methods Male C57Bl/6 mice were subjected to focal cerebral ischemia and periods of reperfusion (0, 8 and 24 h. The microglia process length/cell and number of endpoints/cell was quantified from immunofluorescent confocal images of brain regions using a skeleton analysis method developed for this study. Live cell morphology and process activity were measured from movies acquired in acute brain slices from GFP-CX3CR1 transgenic mice after IS and 24-h reperfusion. Regional CD11b and iNOS expressions were measured from confocal images and Western blot, respectively, to assess microglia proinflammatory function. Results Quantitative analysis reveals a significant spatiotemporal relationship between microglia morphology and evolving cerebral injury in the ipsilateral hemisphere after IS and reperfusion. Microglia were both hyper- and de-ramified in striatal and cortical brain regions (respectively after 60 min of focal cerebral ischemia. However, a de-ramified morphology was prominent when ischemia was coupled to reperfusion. Live microglia were de-ramified, and, in addition, process activity was severely blunted proximal to

Transcriptomics and proteomics analyses of the PACAP38 influenced ischemic brain in permanent middle cerebral artery occlusion model mice

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Hori Motohide

2012-11-01

Full Text Available Abstract Introduction The neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP is considered to be a potential therapeutic agent for prevention of cerebral ischemia. Ischemia is a most common cause of death after heart attack and cancer causing major negative social and economic consequences. This study was designed to investigate the effect of PACAP38 injection intracerebroventrically in a mouse model of permanent middle cerebral artery occlusion (PMCAO along with corresponding SHAM control that used 0.9% saline injection. Methods Ischemic and non-ischemic brain tissues were sampled at 6 and 24 hours post-treatment. Following behavioral analyses to confirm whether the ischemia has occurred, we investigated the genome-wide changes in gene and protein expression using DNA microarray chip (4x44K, Agilent and two-dimensional gel electrophoresis (2-DGE coupled with matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS, respectively. Western blotting and immunofluorescent staining were also used to further examine the identified protein factor. Results Our results revealed numerous changes in the transcriptome of ischemic hemisphere (ipsilateral treated with PACAP38 compared to the saline-injected SHAM control hemisphere (contralateral. Previously known (such as the interleukin family and novel (Gabra6, Crtam genes were identified under PACAP influence. In parallel, 2-DGE analysis revealed a highly expressed protein spot in the ischemic hemisphere that was identified as dihydropyrimidinase-related protein 2 (DPYL2. The DPYL2, also known as Crmp2, is a marker for the axonal growth and nerve development. Interestingly, PACAP treatment slightly increased its abundance (by 2-DGE and immunostaining at 6 h but not at 24 h in the ischemic hemisphere, suggesting PACAP activates neuronal defense mechanism early on. Conclusions This study provides a detailed inventory of PACAP influenced gene expressions

Hexane extracts of Polygonum multiflorum improve tissue and functional outcome following focal cerebral ischemia in mice.

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Lee, Soo Vin; Choi, Kyung Ha; Choi, Young Whan; Hong, Jin Woo; Baek, Jin Ung; Choi, Byung Tae; Shin, Hwa Kyoung

2014-04-01

Polygonum multiflorum is a traditional Korean medicine that has been utilized widely in East Asian countries as a longevity agent. Clinical studies have demonstrated that Polygonum multiflorum improves hypercholesterolemia, coronary heart disease, neurosis and other diseases commonly associated with aging. However, scientific evidence defining the protective effects and mechanisms of Polygonum multiflorum against ischemic stroke is incomplete. In the present study, we investigated the cerebrovascular protective effects of Polygonum multiflorum against ischemic brain injury using an in vivo photothrombotic mouse model. To examine the underlying mechanism of action, we utilized an in vitro human brain microvascular endothelial cell (HBMEC) culture system. Hexane extracts (HEPM), ethyl acetate extracts (EAEPM) and methanol extracts (MEPM) of Polygonum multiflorum (100 mg/kg) were administered intraperitoneally 30 min prior to ischemic insult. Focal cerebral ischemia was induced in C57BL/6J mice and endothelial nitric oxide synthase knockout (eNOS KO) mice by photothrombotic cortical occlusion. We evaluated the infarct volume, as well as neurological and motor function, 24 h after ischemic brain injury. Following ischemic insult, HEPM induced a significant reduction in infarct volume and subsequent neurological deficits, compared with EAEPM and MEPM. HEPM significantly decreased infarct size and improved neurological and motor function, which was not observed in eNOS KO mice, suggesting that this cerebroprotective effect is primarily an eNOS-dependent mechanism. In vitro, HEPM effectively promoted NO production, however these effects were inhibited by the NOS inhibitor, L-NAME and the PI3K/Akt inhibitor, LY-294002. Furthermore, HEPM treatment resulted in increased phosphorylation-dependent activation of Akt and eNOS in HBMEC, suggesting that HEPM increased NO production via phosphorylation-dependent activation of Akt and eNOS. In conclusion, HEPM prevents cerebral

Regulatory T cells are strong promoters of acute ischemic stroke in mice by inducing dysfunction of the cerebral microvasculature.

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Kleinschnitz, Christoph; Kraft, Peter; Dreykluft, Angela; Hagedorn, Ina; Göbel, Kerstin; Schuhmann, Michael K; Langhauser, Friederike; Helluy, Xavier; Schwarz, Tobias; Bittner, Stefan; Mayer, Christian T; Brede, Marc; Varallyay, Csanad; Pham, Mirko; Bendszus, Martin; Jakob, Peter; Magnus, Tim; Meuth, Sven G; Iwakura, Yoichiro; Zernecke, Alma; Sparwasser, Tim; Nieswandt, Bernhard; Stoll, Guido; Wiendl, Heinz

2013-01-24

We have recently identified T cells as important mediators of ischemic brain damage, but the contribution of the different T-cell subsets is unclear. Forkhead box P3 (FoxP3)-positive regulatory T cells (Tregs) are generally regarded as prototypic anti-inflammatory cells that maintain immune tolerance and counteract tissue damage in a variety of immune-mediated disorders. In the present study, we examined the role of Tregs after experimental brain ischemia/reperfusion injury. Selective depletion of Tregs in the DEREG mouse model dramatically reduced infarct size and improved neurologic function 24 hours after stroke and this protective effect was preserved at later stages of infarct development. The specificity of this detrimental Treg effect was confirmed by adoptive transfer experiments in wild-type mice and in Rag1(-/-) mice lacking lymphocytes. Mechanistically, Tregs induced microvascular dysfunction in vivo by increased interaction with the ischemic brain endothelium via the LFA-1/ICAM-1 pathway and platelets and these findings were confirmed in vitro. Ablation of Tregs reduced microvascular thrombus formation and improved cerebral reperfusion on stroke, as revealed by ultra-high-field magnetic resonance imaging at 17.6 Tesla. In contrast, established immunoregulatory characteristics of Tregs had no functional relevance. We define herein a novel and unexpected role of Tregs in a primary nonimmunologic disease state.

[Sensitivity and specificity of the cerebral blood flow reactions to acupuncture in the newborn infants presenting with hypoxic ischemic encephalopathy].

Science.gov (United States)

Filonenko, A V; Vasilenko, A M; Khan, M A

2015-01-01

To evaluate the effects of acupuncture integrated into the standard therapy, the condition of cerebral blood flow, and other syndromes associated with cerebral ischemia in the newborn infants. MATERIAL AND METHODS. A total of 131 pairs of puerperae and newborns with hypoxic ischemic encephalopathy were divided into four treatment groups. 34 children of the first group were given standard therapy (control), in the second group comprised of 33 mothers and children the standard treatment was supplemented by acupuncture, the third group included only 32 mothers given the acupuncture treatment alone, and the fourth group contained only 32 newborn infants treated by acupuncture. Each course of acupuncture treatment consisted of five sessions. Sensitivity and specificity of cerebral blood flow reactions were determined based on the results of the ROC-analysis and the area under the curve before and after the treatment. The treatment with the use of acupuncture greatly improved the cerebrospinal hemodynamics (p newborn babies. The high level of sensitivity (84.4-94.8%) associated with good specificity makes it possible to distinguish between the true positive and true negative cases. Acupuncture integrated into the treatment of "mother-baby" pairs presenting with hypoxic ischemic encephalopathy can be used to improve the initially low level of cerebral blood flow in neonates presenting with this condition.

Effects of total saponins from Trillium tschonoskii rhizome on grey and white matter injury evaluated by quantitative multiparametric MRI in a rat model of ischemic stroke.

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Li, Manzhong; Ouyang, Junyao; Zhang, Yi; Cheng, Brian Chi Yan; Zhan, Yu; Yang, Le; Zou, Haiyan; Zhao, Hui

2018-04-06

Trillium tschonoskii rhizome (TTR), a medicinal herb, has been traditionally used to treat traumatic brain injury and headache in China. Although the potential neuroprotective efficacy of TTR has gained increasing interest, the pharmacological mechanism remains unclear. Steroid saponins are the main bioactive components of the herb. To investigate the protective and repair-promoting effects of the total saponins from TTR (TSTT) on grey and white matter damages in a rat model of middle cerebral artery occlusion (MCAO) using magnetic resonance imaging (MRI) assay. Ischemic stroke was induced by MCAO. TSTT and Ginaton (positive control) were administered orally to rats 6h after stroke and daily thereafter. After 15 days of treatment, the survival rate of each group was calculated. We then conducted neurological deficit scores and beam walking test to access the neurological function after ischemic stroke. Subsequently, T2-weighted imaging (T2WI) and T2 relaxometry mapping were performed to measure infarct volume and grey and white matter integrity, respectively. Moreover, diffusion tensor imaging (DTI) was carried out to evaluate the grey and white matter microstructural damage. Additionally, arterial spin labelling (ASL) - cerebral blood flow (CBF) and magnetic resonance angiography (MRA) images provided dynamic information about vascular hemodynamic dysfunction after ischemic stroke. Finally, haematoxylin and eosin (HE) staining was carried out to evaluate the stroke-induced pathological changes in the brain. The survival rate and neurological behavioural outcomes (Bederson scores and beam walking tests) were markedly ameliorated by TSTT (65mg/kg) treatment within 15 days after ischemic stroke. Moreover, T2WI and T2 relaxometry mapping showed that TSTT (65mg/kg) significantly reduced infarct volume and attenuated grey and white matter injury, respectively, which was confirmed by histopathological evaluation of brain tissue. The results obtained from DTI showed that

Cerebral Microbleeds Are Not Associated with Long-Term Cognitive Outcome in Patients with Transient Ischemic Attack or Minor Stroke

NARCIS (Netherlands)

Brundel, Manon; Kwa, Vincent I. H.; Bouvy, Willem H.; Algra, Ale; Kappelle, L. Jaap; Biessels, Geert Jan; Algra, A.; Kappelle, L. J.; Ramos, L. M. P.; de Schryver, E. L. L. M.; Kwa, V. I. H.; Jöbsis, G. J.; van der Sande, J. J.; Brouwers, P. J. A. M.; Roos, Y. E. B. M.; Stam, J.; Bakker, S. L. M.; Verbiest, H. B. C.; Schoonewille, W. J.; Linn, F. H. H.; Hertzberger, L. I.; van Gemert, H. M. A.; Berntsen, P. J. I. M.

2014-01-01

Background: Cerebral microbleeds have been related to cerebrovascular disease and dementia. They occur more frequently in patients with ischemic stroke than in the general population, but their relation to cognition in these patients is uncertain, particularly in the long run. We examined the

Remote Ischemic Conditioning to Protect against Ischemia-Reperfusion Injury: A Systematic Review and Meta-Analysis

Science.gov (United States)

Brevoord, Daniel; Kranke, Peter; Kuijpers, Marijn; Weber, Nina; Hollmann, Markus; Preckel, Benedikt

2012-01-01

Background Remote ischemic conditioning is gaining interest as potential method to induce resistance against ischemia reperfusion injury in a variety of clinical settings. We performed a systematic review and meta-analysis to investigate whether remote ischemic conditioning reduces mortality, major adverse cardiovascular events, length of stay in hospital and in the intensive care unit and biomarker release in patients who suffer from or are at risk for ischemia reperfusion injury. Methods and Results Medline, EMBASE and Cochrane databases were searched for randomized clinical trials comparing remote ischemic conditioning, regardless of timing, with no conditioning. Two investigators independently selected suitable trials, assessed trial quality and extracted data. 23 studies in patients undergoing cardiac surgery (15 studies), percutaneous coronary intervention (four studies) and vascular surgery (four studies), comprising in total 1878 patients, were included in this review. Compared to no conditioning, remote ischemic conditioning did not reduce mortality (odds ratio 1.22 [95% confidence interval 0.48, 3.07]) or major adverse cardiovascular events (0.65 [0.38, 1.14]). However, the incidence of myocardial infarction was reduced with remote ischemic conditioning (0.50 [0.31, 0.82]), as was peak troponin release (standardized mean difference −0.28 [−0.47, −0.09]). Conclusion There is no evidence that remote ischemic conditioning reduces mortality associated with ischemic events; nor does it reduce major adverse cardiovascular events. However, remote ischemic conditioning did reduce the incidence of peri-procedural myocardial infarctions, as well as the release of troponin. PMID:22860077

Clinical significance of cerebral microbleeds on MRI : A comprehensive meta-analysis of risk of intracerebral hemorrhage, ischemic stroke, mortality, and dementia in cohort studies (vI)

NARCIS (Netherlands)

A. Charidimou (Andreas); S. Shams (Sara); J.R. Romero (Jose Rafael); J. Ding (Jie); R. Veltkamp (Roland); S. Horstmann (Solveig); G. Eiriksdottir (Gudny); M.A. van Buchem (Mark); V. Gudnason (Vilmundur); J.J. Himali (Jayandra); M.E. Gurol (Edip); A. Viswanathan (Anand); T. Imaizumi (Toshio); M.W. Vernooij (Meike); S. Seshadri (Sudha); S.M. Greenberg (Steven); O.R. Benavente (Oscar); L.J. Launer (Lenore); A. Shoamanesh (Ashkan)

2018-01-01

markdownabstract__Background:__ Cerebral microbleeds can confer a high risk of intracerebral hemorrhage, ischemic stroke, death and dementia, but estimated risks remain imprecise and often conflicting. We investigated the association between cerebral microbleeds presence and these outcomes in a

Parameterized entropy analysis of EEG following hypoxic-ischemic brain injury

International Nuclear Information System (INIS)

Tong Shanbao; Bezerianos, Anastasios; Malhotra, Amit; Zhu Yisheng; Thakor, Nitish

2003-01-01

In the present study Tsallis and Renyi entropy methods were used to study the electric activity of brain following hypoxic-ischemic (HI) injury. We investigated the performances of these parameterized information measures in describing the electroencephalogram (EEG) signal of controlled experimental animal HI injury. The results show that (a): compared with Shannon and Renyi entropy, the parameterized Tsallis entropy acts like a spatial filter and the information rate can either tune to long range rhythms or to short abrupt changes, such as bursts or spikes during the beginning of recovery, by the entropic index q; (b): Renyi entropy is a compact and predictive indicator for monitoring the physiological changes during the recovery of brain injury. There is a reduction in the Renyi entropy after brain injury followed by a gradual recovery upon resuscitation

Stress test with adenosine in cerebral perfusion imaging for the diagnosis of ischemic cerebrovascular disease

International Nuclear Information System (INIS)

Yuan Gengbiao; Kuang Anren; Chen Xuehong; Li Xihuan; Feng Jianzhong

2004-01-01

Objective: This study purpose is to evaluate cerebrovascular response and reserve capacity (CVR, CVRC) by stress test with adenosine in cerebral perfusion imaging for the diagnosis of ischemic cerebrovascular diseases. Methods There were 25 patients suffered from transient ischemia attack and 16 patients suffered from occlusive cerebral artery in this study. The rest cerebral perfusion imaging was obtained 30 minutes post-injection of 99mTC-ethylene cysteinate dimmer. After 2-5 days, adenosine stress tests were performed. Adenosine (0.14 mg/kg min) was administered intravenously 3 minutes pre-injection of 99mTC-ECD.Under same condition, the rest and stress tests of cerebral perfusion imaging were performed. By visual and semiquantitative analysis, the results of the rest/stress imaging were divided into the following four patterns: A: The stress imaging showed an expand areas of hypoperfusion, asymmetry index (AI) was decreased; B: Rest imaging was normal but new hypoperfused areas appeared with AI index declining in stress test; C: The hypoperfused areas were decreased or disappeared in size with AI index increasing in stress test; D: No changes showed in cerebral perfusion imaging patterns and Al index between rest and stress tests. AI index was ratio of radio account of interest regions than average radio account of cerebella. Results It was found that A, B, C and D type were 24%,12%,56% and 8% respectively in the group of transient ischemia attack patients, and 31%,44%, 19% and 6% respectively in the group of occlusive cerebrovascular patients. In rest test, of 41 patients of cerebrovascular disease, there were 28 cases decreased of radio uptake, moreover in stress test, there were 38 case decreased of radio uptake, positive rate were 68.29% and 92.68% respectively. Compared to X±SD of AI index of rest/stress test, it is found to increasing and being significant statistics (p<0.01, Spass 8.0 statistics software). Conclusion: Adenosinal-induced vasodilatation

Term Neonate with Atypical Hypoxic-Ischemic Encephalopathy Presentation: A Case Report.

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Townley, Nick; McNellis, Emily; Sampath, Venkatesh

2017-07-01

We describe a case of atypical hypoxic-ischemic encephalopathy (HIE) in a neonate following a normal pregnancy and delivery who was found to have an umbilical vein thrombosis. The infant arrived to our center with continuous bicycling movement of her lower extremities. She had a continuous electroencephalogram that showed burst suppression and magnetic resonance imaging of the brain showed diffusely abnormal cerebral cortical/subcortical diffusion restriction which may be secondary hypoxic-ischemic injury. Interestingly, a pathology report noted a focal umbilical vein thrombosis appearing to have compressed an umbilical artery with associated arterial dissection and hematoma. Our case illustrates how umbilical venous or arterial thrombosis may be associated with HIE and refractory seizures.

The Protective Effect of Human Umbilical Cord Blood CD34+ Cells and Estradiol against Focal Cerebral Ischemia in Female Ovariectomized Rat: Cerebral MR Imaging and Immunohistochemical Study.

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Ching-Chung Liang

Full Text Available Human umbilical cord blood derived CD34+ stem cells are reported to mediate therapeutic effects in stroke animal models. Estrogen was known to protect against ischemic injury. The present study wished to investigate whether the protective effect of CD34+ cells against ischemic injury can be reinforced with complemental estradiol treatment in female ovariectomized rat and its possible mechanism. Experiment 1 was to determine the best optimal timing of CD34+ cell treatment for the neuroprotective effect after 60-min middle cerebral artery occlusion (MCAO. Experiment 2 was to evaluate the adjuvant effect of 17β-estradiol on CD34+ cell neuroprotection after MCAO. Experiment 1 showed intravenous infusion with CD34+ cells before MCAO (pre-treatment caused less infarction size than those infused after MCAO (post-treatment on 7T magnetic resonance T2-weighted images. Experiment 2 revealed infarction size was most significantly reduced after CD34+ + estradiol pre-treatment. When compared with no treatment group, CD34+ + estradiol pre-treatment showed significantly less ADC reduction at 2 h and 2 d, less CBF reduction at 2 h and less hyperperfusion at 2 d. The immunoreactivity of c-Fos, c-Jun and GFAP was attenuated, and BDNF showed significant recovery from 2 h to 2 d after MCAO, especially after CD34+ + estradiol pre-treatment. The present study suggests pre-treatment with CD34+ cells with complemental estradiol can be most protective against ischemic injury, which may act through stabilization of cerebral hemodynamics and normalization of the expressions of immediate early genes and BDNF.

Antiarrhythmic effect of heat adaptation in ischemic and reperfusion injury to the heart.

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Monastyrskaya, E A; Belkina, L M; Manukhina, E B; Malyshev, I Yu

2007-01-01

Study on a model of 6-day dosed adaptation to heat in rats showed that this adaptation decreased the severity of cardiac arrhythmias during ischemic and reperfusion injury. The duration of arrhythmias decreased not only in the ischemic period, but also under conditions of reperfusion. Adaptation delayed the development of arrhythmias during ischemia, decreased the number of animals with late reperfusion arrhythmias, and improved recovery of the heart after ischemia and reperfusion.

No improvement of neuronal metabolism in the reperfusion phase with melatonin treatment after hypoxic-ischemic brain injury in the neonatal rat.

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Berger, Hester R; Morken, Tora Sund; Vettukattil, Riyas; Brubakk, Ann-Mari; Sonnewald, Ursula; Widerøe, Marius

2016-01-01

Mitochondrial impairment is a key feature underlying neonatal hypoxic-ischemic (HI) brain injury and melatonin is potentially neuroprotective through its effects on mitochondria. In this study, we have used (1) H and (13) C NMR spectroscopy after injection of [1-(13) C]glucose and [1,2-(13) C]acetate to examine neuronal and astrocytic metabolism in the early reperfusion phase after unilateral HI brain injury in 7-day-old rat pups, exploring the effects of HI on mitochondrial function and the potential protective effects of melatonin on brain metabolism. One hour after hypoxia-ischemia, astrocytic metabolism was recovered and glycolysis was normalized, whereas mitochondrial metabolism in neurons was clearly impaired. Pyruvate carboxylation was also lower in both hemispheres after HI. The transfer of glutamate from neurons to astrocytes was higher whereas the transfer of glutamine from astrocytes to neurons was lower 1 h after HI in the contralateral hemisphere. Neuronal metabolism was equally affected in pups treated with melatonin (10 mg/kg) immediately after HI as in vehicle treated pups indicating that the given dose of melatonin was not capable of protecting the neuronal mitochondria in this early phase after HI brain injury. However, any beneficial effects of melatonin might have been masked by modulatory effects of the solvent dimethyl sulfoxide on cerebral metabolism. Neuronal and astrocytic metabolism was examined by (13) C and (1) H NMR spectroscopy in the early reperfusion phase after unilateral hypoxic-ischemic brain injury and melatonin treatment in neonatal rats. One hour after hypoxia-ischemia astrocytic mitochondrial metabolism had recovered and glycolysis was normalized, whereas mitochondrial metabolism in neurons was impaired. Melatonin treatment did not show a protective effect on neuronal metabolism. © 2015 International Society for Neurochemistry.

Evaluation of the Effects of Atorvastatin and Ischemic Postconditioning Preventing on the Ischemia and Reperfusion Injury: Experimental Study in Rats

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Henrique Budib Dorsa Pontes

Full Text Available Abstract Introduction: Reperfusion injury leads to systemic morphological and functional pathological alterations. Some techniques are already estabilished to attenuate the damage induced by reperfusion. Ischemic preconditioning is one of the standard procedures. In the last 20 years, several experimental trials demonstrated that the ischemic postconditioning presents similar effectiveness. Recently experimental trials demonstrated that statins could be used as pharmacological preconditioning. Methods: 41 Wistar rats (Rattus norvegicus albinus were distributed in 5 groups: Ischemia and Reperfusion (A, Ischemic Postconditioning (B, Statin (C, Ischemic Postconditioning + Statins (D and SHAM (E. After euthanasia, lungs, liver, kidneys and ileum were resected and submitted to histopathological analysis. Results: The average of lung parenchymal injury was A=3.6, B=1.6, C=1.2, D=1.2, E=1 (P=0.0029. The average of liver parenchymal injury was A=3, B=1.5, C=1.2, D=1.2, E = 0 (P<0.0001. The average of renal parenchymal injury was A=4, B=2.44, C=1.22, D=1.11, E=1 (P<0.0001. The average of intestinal parenchymal injury was A=2, B=0.66, C=0, D=0, E=0 (P=0.0006. The results were submitted to statistics applying Kruskal-Wallis test, estabilishing level of significance P<0.05. Conclusion: Groups submitted to ischemic postconditioning, to pre-treatment with statins and both methods associated demonstrated less remote reperfusion injuries, compared to the group submitted to ischemia and reperfusion without protection.

The application of functional MRI in evaluating ischemic injuries of lower limb skeletal muscle

International Nuclear Information System (INIS)

Xia Caifeng; Gu Jianping

2011-01-01

The ischemic injury of lower limb skeletal muscle is caused by various reasons that lead to limb arterial blood flow insufficiency and subsequent muscle tissue hypoxia. Exact and correct evaluation of the ischemic degree of the skeletal muscle is very important for the physicians to guide the clinical treatment, to assess the therapeutic effect and to judge the prognosis. With the development and updating of scanning hardware and software, together with the use of diffusion-weighted imaging (DWI), diffusion tensor imaging (DTI), perfusion-weighted imaging (PWI), blood oxygen level dependent (BOLD) imaging and magnetic resonance spectroscopy (MRS), etc. the application of MRI has been dramatically expanded both in clinical practice and scientific researches. Nowadays, functional MRI can accurately reflect the physiological structures and pathologic changes in detail. This article aims mainly to make a comprehensive review about the application of these techniques in assessing the ischemic injuries of lower limb skeletal muscle. (authors)

Is elevated SUA associated with a worse outcome in young Chinese patients with acute cerebral ischemic stroke?

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Zhang Bin

2010-09-01

Full Text Available Abstract Background Elevated serum uric acid (SUA levels can enhance its antioxidant prosperities and reduce the occurrence of cerebral infarction. Significantly elevated SUA levels have been associated with a better prognosis in patients with cerebral infarction; however, the results from some studies on the relationship between SUA and the prognosis of patients with cerebral infarction remain controversial. Methods We analyzed the relationship between SUA and clinical prognosis of 585 young Chinese adults with acute ischemic stroke as determined by the modified Rankin Scale at discharge. Using multivariate logistic regression modeling, we explore the relationship between SUA levels and patient's clinical prognosis. Results Lower SUA levels at time of admission were observed more frequently in the lowest quintile for patients with severe stroke (P = 0.02. Patients with cerebral infarction patients caused by small-vessel blockage had higher SUA concentrations (P = 0.01 and the lower mRS scores (P Conclusion Elevated SUA is an independent predictor for good clinical outcome of acute cerebral infarction among young adults.

Andrographolide stimulates p38 mitogen-activated protein kinase-nuclear factor erythroid-2-related factor 2-heme oxygenase 1 signaling in primary cerebral endothelial cells for definite protection against ischemic stroke in rats.

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Yen, Ting-Lin; Chen, Ray-Jade; Jayakumar, Thanasekaran; Lu, Wan-Jung; Hsieh, Cheng-Ying; Hsu, Ming-Jen; Yang, Chih-Hao; Chang, Chao-Chien; Lin, Yen-Kuang; Lin, Kuan-Hung; Sheu, Joen-Rong

2016-04-01

Stroke pathogenesis involves complex oxidative stress-related pathways. The nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) pathways have been considered molecular targets in pharmacologic intervention for ischemic diseases. Andrographolide, a labdane diterpene, has received increasing attention in recent years because of its various pharmacologic activities. We determined that andrographolide modulates the mitogen-activated protein kinase (MAPK)-Nrf2-HO-1 signaling cascade in primary cerebral endothelial cells (CECs) to provide positive protection against middle cerebral artery occlusion (MCAO)-induced ischemic stroke in rats. In the present study, andrographolide (10 μM) increased HO-1 protein and messenger RNA expressions, Nrf2 phosphorylation, and nuclear translocation in CECs, and these activities were disrupted by a p38 MAPK inhibitor, SB203580, but not by the extracellular signal-regulated kinase inhibitor PD98059 or c-Jun amino-terminal kinase inhibitor SP600125. Similar results were observed in confocal microscopy analysis. Moreover, andrographolide-induced Nrf2 and HO-1 protein expressions were significantly inhibited by Nrf2 small interfering RNA. Moreover, HO-1 knockdown attenuated the protective effect of andrographolide against oxygen-glucose deprivation-induced CEC death. Andrographolide (0.1 mg/kg) significantly suppressed free radical formation, blood-brain barrier disruption, and brain infarction in MCAO-insulted rats, and these effects were reversed by the HO-1 inhibitor zinc protoporphyrin IX. The mechanism is attributable to HO-1 activation, as directly evidenced by andrographolide-induced pronounced HO-1 expression in brain tissues, which was highly localized in the cerebral capillary. In conclusion, andrographolide increased Nrf2-HO-1 expression through p38 MAPK regulation, confirming that it provides protection against MCAO-induced brain injury. These findings provide strong evidence that andrographolide could

Pilocarpine-induced status epilepticus in rats involves ischemic and excitotoxic mechanisms.

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Paolo Francesco Fabene

Full Text Available The neuron loss characteristic of hippocampal sclerosis in temporal lobe epilepsy patients is thought to be the result of excitotoxic, rather than ischemic, injury. In this study, we assessed changes in vascular structure, gene expression, and the time course of neuronal degeneration in the cerebral cortex during the acute period after onset of pilocarpine-induced status epilepticus (SE. Immediately after 2 hr SE, the subgranular layers of somatosensory cortex exhibited a reduced vascular perfusion indicative of ischemia, whereas the immediately adjacent supragranular layers exhibited increased perfusion. Subgranular layers exhibited necrotic pathology, whereas the supergranular layers were characterized by a delayed (24 h after SE degeneration apparently via programmed cell death. These results indicate that both excitotoxic and ischemic injuries occur during pilocarpine-induced SE. Both of these degenerative pathways, as well as the widespread and severe brain damage observed, should be considered when animal model-based data are compared to human pathology.

Computer-aided diagnosis of acute ischemic stroke based on cerebral hypoperfusion using 4D CT angiography

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Charbonnier, Jean-Paul; Smit, Ewoud J.; Viergever, Max A.; Velthuis, Birgitta K.; Vos, Pieter C.

2013-02-01

The presence of collateral blood flow is found to be a strong predictor of patient outcome after acute ischemic stroke. Collateral blood flow is defined as an alternative way to provide oxygenated blood to ischemic cerebral tissue. Assessment of collateral blood supply is currently performed by visual inspection of a Computed Tomography Angiogram (CTA) which introduces inter-observer variability and depends on the grading scale. Furthermore, variations in the arterial contrast arrival time may lead to underestimation of collateral blood supply in a CTA which exerts a negative influence on the prediction of patient outcome. In this study, the feasibility of a Computer-aided Diagnosis system is investigated capable of objectively predicting patient outcome. We present a novel automatic method for quantitative assessment of cerebral hypoperfusion in timing-invariant (i.e. delay insensitive) CTA (TI-CTA). The proposed Vessel Density Symmetry algorithm automatically generates descriptive maps based on hemispheric asymmetry of blood vessels. Intensity and symmetry based features are extracted from these descriptive maps and subjected to a best-first-search feature selection. Linear Discriminant Analysis is performed to combine selected features into a likelihood of good patient outcome. Receiver operating characteristic (ROC) analysis is conducted to evaluate the diagnostic performance of the CAD by leave-one- patient-out cross validation. A Positive Predicting Value of 1 was obtained at a sensitivity of 25% with an area under the ROC-curve of 0.86. The results show that the CAD is feasible to objectively predict patient outcome. The presented CAD could make an important contribution to acute ischemic stroke diagnosis and treatment.

Neuroanatomic correlates of stroke-related myocardial injury.

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Ay, H; Koroshetz, W J; Benner, T; Vangel, M G; Melinosky, C; Arsava, E M; Ayata, C; Zhu, M; Schwamm, L H; Sorensen, A G

2006-05-09

Myocardial injury can occur after ischemic stroke in the absence of primary cardiac causes. The neuroanatomic basis of stroke-related myocardial injury is not well understood. To identify regions of brain infarction associated with myocardial injury using a method free of the bias of an a priori hypothesis as to any specific location. Of 738 consecutive patients with acute ischemic stroke, the authors identified 50 patients in whom serum cardiac troponin T (cTnT) elevation occurred in the absence of any apparent cause within 3 days of symptom onset. Fifty randomly selected, age- and sex-matched patients with ischemic stroke without cTnT elevation served as controls. Diffusion-weighted images with outlines of infarction were co-registered to a template, averaged, and then subtracted to find voxels that differed between the two groups. Voxel-wise p values were determined using a nonparametric permutation test to identify specific regions of infarction that were associated with cTnT elevation. The study groups were well balanced with respect to stroke risk factors, history of coronary artery disease, infarction volume, and frequency of right and left middle cerebral artery territory involvement. Brain regions that were a priori associated with cTnT elevation included the right posterior, superior, and medial insula and the right inferior parietal lobule. Among patients with right middle cerebral artery infarction, the insular cluster was involved in 88% of patients with and 33% without cTnT elevation (odds ratio: 15.00; 95% CI: 2.65 to 84.79). Infarctions in specific brain regions including the right insula are associated with elevated serum cardiac troponin T level indicative of myocardial injury.

Glucose administration after traumatic brain injury improves cerebral metabolism and reduces secondary neuronal injury.

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Moro, Nobuhiro; Ghavim, Sima; Harris, Neil G; Hovda, David A; Sutton, Richard L

2013-10-16

Clinical studies have indicated an association between acute hyperglycemia and poor outcomes in patients with traumatic brain injury (TBI), although optimal blood glucose levels needed to maximize outcomes for these patients' remain under investigation. Previous results from experimental animal models suggest that post-TBI hyperglycemia may be harmful, neutral, or beneficial. The current studies determined the effects of single or multiple episodes of acute hyperglycemia on cerebral glucose metabolism and neuronal injury in a rodent model of unilateral controlled cortical impact (CCI) injury. In Experiment 1, a single episode of hyperglycemia (50% glucose at 2 g/kg, i.p.) initiated immediately after CCI was found to significantly attenuate a TBI-induced depression of glucose metabolism in cerebral cortex (4 of 6 regions) and subcortical regions (2 of 7) as well as to significantly reduce the number of dead/dying neurons in cortex and hippocampus at 24 h post-CCI. Experiment 2 examined effects of more prolonged and intermittent hyperglycemia induced by glucose administrations (2 g/kg, i.p.) at 0, 1, 3 and 6h post-CCI. The latter study also found significantly improved cerebral metabolism (in 3 of 6 cortical and 3 of 7 subcortical regions) and significant neuroprotection in cortex and hippocampus 1 day after CCI and glucose administration. These results indicate that acute episodes of post-TBI hyperglycemia can be beneficial and are consistent with other recent studies showing benefits of providing exogenous energy substrates during periods of increased cerebral metabolic demand. © 2013 Elsevier B.V. All rights reserved.

Acute kidney injury and edaravone in acute ischemic stroke: the Fukuoka Stroke Registry.

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Kamouchi, Masahiro; Sakai, Hironori; Kiyohara, Yutaka; Minematsu, Kazuo; Hayashi, Kunihiko; Kitazono, Takanari

2013-11-01

A free radical scavenger, edaravone, which has been used for the treatment of ischemic stroke, was reported to cause acute kidney injury (AKI) as a fatal adverse event. The aim of the present study was to clarify whether edaravone is associated with AKI in patients with acute ischemic stroke. From the Fukuoka Stroke Registry database, 5689 consecutive patients with acute ischemic stroke who were hospitalized within 24 hours of the onset of symptoms were included in this study. A logistic regression analysis for the Fukuoka Stroke Registry cohort was done to identify the predictors for AKI. A propensity score-matched nested case-control study was also performed to elucidate any association between AKI and edaravone. Acute kidney injury occurred in 128 of 5689 patients (2.2%) with acute ischemic stroke. A multivariate analysis revealed that the stroke subtype, the basal serum creatinine level, and the presence of infectious complications on admission were each predictors of developing AKI. In contrast, a free radical scavenger, edaravone, reduced the risk of developing AKI (multivariate-adjusted odds ratio [OR] .45, 95% confidence interval [CI] .30-.67). Propensity score-matched case-control study confirmed that edaravone use was negatively associated with AKI (propensity score-adjusted OR .46, 95% CI .29-.74). Although AKI has a significant impact on the clinical outcome of hospital inpatients, edaravone has a protective effect against the development of AKI in patients with acute ischemic stroke. Copyright © 2013 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Cerebral blood flow in acute and chronic ischemic stroke using xenon-133 inhalation tomography

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Vorstrup, S; Paulson, O B; Lassen, N A

1986-01-01

Serial measurements of cerebral blood flow (CBF) were performed in 12 patients with acute symptoms of ischemic cerebrovascular disease. CBF was measured by xenon-133 inhalation and single photon emission computer tomography. Six patients had severe strokes and large infarcts on the CT scan....... They showed in the acute phase (Days 1-3) very large low-flow areas, larger than the hypodense areas seen on the CT scan. The cerebral vasoconstrictor and vasodilator capacity was tested in the acute phase following aminophylline and acetazolamide, respectively. A preserved but reduced reactivity was seen...... had occlusion of the relevant internal carotid artery. In all 6 patients, CBF studies at 2 and 6 months resembled the acute phase, showing large areas with reduced flow. At the 6 months follow-up, the vasodilatory stress test was repeated, and all but one showed a preserved but reduced vasoreactivity...

Differential Temporal Evolution Patterns in Brain Temperature in Different Ischemic Tissues in a Monkey Model of Middle Cerebral Artery Occlusion

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Zhihua Sun

2012-01-01

Full Text Available Brain temperature is elevated in acute ischemic stroke, especially in the ischemic penumbra (IP. We attempted to investigate the dynamic evolution of brain temperature in different ischemic regions in a monkey model of middle cerebral artery occlusion. The brain temperature of different ischemic regions was measured with proton magnetic resonance spectroscopy (1H MRS, and the evolution processes of brain temperature were compared among different ischemic regions. We found that the normal (baseline brain temperature of the monkey brain was 37.16°C. In the artery occlusion stage, the mean brain temperature of ischemic tissue was 1.16°C higher than the baseline; however, this increase was region dependent, with 1.72°C in the IP, 1.08°C in the infarct core, and 0.62°C in the oligemic region. After recanalization, the brain temperature of the infarct core showed a pattern of an initial decrease accompanied by a subsequent increase. However, the brain temperature of the IP and oligemic region showed a monotonously and slowly decreased pattern. Our study suggests that in vivo measurement of brain temperature could help to identify whether ischemic tissue survives.

Ischemic Retinopathy and Neovascular Proliferation Secondary to Severe Head Injury

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Muge Coban-Karatas

2014-01-01

Full Text Available We report a case with severe head trauma and perforating globe injury in one eye and ischemic retinopathy and neovascular proliferation in the other eye. A 37-year-old male was brought to the emergency department after a motor vehicle accident with severe maxillofacial trauma. Ophthalmic examination revealed hematoma of the left eyelids as well as traumatic rupture and disorganization of the left globe. On the right eye, anterior segment and fundoscopic examination were normal. Primary globe repair was performed. At postoperative one-month visit, the right eye revealed no pathology of the optic disc and macula but severe neovascularization in the temporal peripheral retina. The patient was diagnosed as ischemic retinopathy and neovascular proliferation due to head trauma.

Clinical application of dynamic digital subtraction angiography in cerebrovascular ischemic diseases

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Hirata, Yoshifumi; Nonaka, Nobuhito; Matsukado, Yasuhiko; Takahashi, Mutsumasa

1987-09-01

Dynamic intravenous digital subtraction angiography (IV-DSA) was performed in 37 patients with cerebrovascular ischemic diseases. The time density curve of IV-DSA was analysed, and peak time, mean transit time and mode of transit time were obtained in each patient. On the basis of these values, cerebral perfusion was classified into low, normal and high perfusion patterns. Normal perfusion pattern was noted in 40% of patients with transient ischemic attack (TIA) and 7 % of patients with cerebral infarction. Low perfusion pattern was observed in 60 % of patients with TIA and 87 % of patients with cerebral infarction. High perfusion pattern was encountered only in 7 % of patients with cerebral infarction. In ischemic patients with moyamoya disease, extremely prolonged cerebral circulation time was evidenced by the presence of a flat or uphill type of the time density curve. This finding well correlated with decreased cerebral blood flow on single photon emission tomography. These findings suggest that the analysis of dynamic DSA is very important and useful in the clinical evaluation of patients with cerebrovascular ischemic diseases.

Reduction of mitochondrial electron transport complex activity is restricted to the ischemic focus after transient focal cerebral ischemia in rats

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Christensen, Thomas; Diemer, Nils Henrik

2003-01-01

Using histochemical methods offering high topographical resolution for evaluation of changes in the ischemic focus and the penumbra, the mitochondrial electron transport chain (ETC) complexes I, II, and IV were examined in rats subjected to 2 h of proximal occlusion of the middle cerebral artery...

Transglutaminase 2 gene ablation protects against renal ischemic injury by blocking constant NF-κB activation

International Nuclear Information System (INIS)

Kim, Dae-Seok; Kim, Bora; Tahk, Hongmin; Kim, Dong-Hyun; Ahn, Eu-Ree; Choi, Changsun; Jeon, Yoon; Park, Seo Young; Lee, Ho; Oh, Seung Hyun; Kim, Soo-Youl

2010-01-01

Research highlights: → No acute renal tubular necrotic lesions were found in TGase2 -/- mice with ischemic kidney injury. → NF-κB activation is reduced in TGase2 -/- mice with ischemic kidney injury. → Hypoxic stress did not increase NF-κB activity in MEFs from TGase2 -/- mice. → COX-2 induction is suppressed in TGase2 -/- mice with ischemic kidney injury. -- Abstract: Transglutaminase 2 knockout (TGase2 -/- ) mice show significantly reduced inflammation with decreased myofibroblasts in a unilateral ureteral obstruction (UUO) model, but the mechanism remains to be clarified. Nuclear factor-κB (NF-κB) activation plays a major role in the progression of inflammation in an obstructive nephropathy model. However, the key factors extending the duration of NF-κB activation in UUO are not known. In several inflammatory diseases, we and others recently found that TGase 2 plays a key role in extending NF-κB activation, which contributes to the pathogenesis of disease. In the current study, we found that NF-κB activity in mouse embryogenic fibroblasts (MEFs) from TGase2 -/- mice remained at the control level while the NF-κB activity of wild-type (WT) MEFs was highly increased under hypoxic stress. Using the obstructive nephropathy model, we found that NF-κB activity remained at the control level in TGase2 -/- mouse kidney tissues, as measured by COX-2 expression, but was highly increased in WT tissues. We conclude that TGase 2 gene ablation reduces the duration of NF-κB activation in ischemic injury.

99mTc-HMPAO Regional Cerebral Blood Flow SPECT in Transient Ischemic Attacks

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Ahn, Myeong Im; Park, Young Ha; Lee, Sung Yong; Chung, Soo Kyo; Kim, Jong Woo; Bahk, Yong Whee

1989-01-01

Transient ischemic attacks (TJAs) is a syndrome resulting from brain ischemia lasting less than 24 hours. The mechanisms of TIAs may be similar to those of cerebral embolism and thrombosis, and thus TIAs may be followed by cerebral infarction. Despite the availability of CT scanning, the diagnosis and management of TIAs continue to be difficult. Recently SPECT has been advocated as a diagnostic imaging modality. We performed 99m Tc-HMPAO regional cerebral blood flow (rCRF) SPECT in 24 patients with the clinical diagnosis of TIAs to assess its ability to detect early changes of rCBF, and determine the diagnostic value. Ten men and fourteen women with an average of 51 years (range; 27-74 years) were included. All but 8 patients had normal brain CT prior to SPECT. The two patients had moderate degree of brain atrophy and the 6 patients nonspecific calcifications. Eighteen of the 24 patients had abnormal 99m Tc-HMPAO rCBF SPECT. Fifteen had unilateral involvement and the other three had bilateral involvements. Seventy-five percents of the defects were found in the left cerebral hemisphere. According to the distribution of the lesions (total number: 34 lesions), fourteen were in the parietal, eight in the temporal, and the remainders were elsewhere. 99m Tc-HMPAO rCHF SPECT is sensitive in detecting rCRF abnormalities in patients with TIAs, and represent the most accurate diagnostic tool available in the diagnosis of TIAs

Lower Serum Caveolin-1 Is Associated with Cerebral Microbleeds in Patients with Acute Ischemic Stroke

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Jun Zhang

2016-01-01

Full Text Available Caveolin-1 (Cav-1 plays pivotal roles in the endothelial damage following stroke. The present study aimed to investigate whether serum Cav-1 level is associated with the presence of cerebral small vessel disease (cSVD in patients with acute ischemic stroke. To this end, 156 patients were consecutively enrolled. Cranial magnetic resonance imaging was analyzed to determine the surrogates of cSVD, including cerebral microbleeds (CMBs, silent lacunar infarcts (SLIs, and white matter hyperintensities (WMHs. After adjusting for potential confounders, patients with low Cav-1 level had a higher risk of CMBs than patients with high Cav-1 level (OR: 4.05, 95% CI: 1.77–9.30. However, there was no relationship between Cav-1 and the presence of SLIs or WMHs. When CMBs were stratified by location and number, a similar association was found in patients with deep or infratentorial CMBs (OR: 4.04, 95% CI: 1.59–10.25 and with multiple CMBs (OR: 3.18, 95% CI: 1.16–8.72. These results suggest lower serum Cav-1 levels may be associated with CMBs, especially those that are multiple and located in deep brain or infratentorial structures, in patients with acute ischemic stroke. Cav-1 may be involved in the pathophysiology of CMBs, and may act as a potential target for treating cSVD.

Effects of Mild Blast Traumatic Brain Injury on Cerebral Vascular, Histopathological, and Behavioral Outcomes in Rats

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Zeng, Yaping; Deyo, Donald; Parsley, Margaret A.; Hawkins, Bridget E.; Prough, Donald S.; DeWitt, Douglas S.

2018-01-01

Abstract To determine the effects of mild blast-induced traumatic brain injury (bTBI), several groups of rats were subjected to blast injury or sham injury in a compressed air-driven shock tube. The effects of bTBI on relative cerebral perfusion (laser Doppler flowmetry [LDF]), and mean arterial blood pressure (MAP) cerebral vascular resistance were measured for 2 h post-bTBI. Dilator responses to reduced intravascular pressure were measured in isolated middle cerebral arterial (MCA) segments, ex vivo, 30 and 60 min post-bTBI. Neuronal injury was assessed (Fluoro-Jade C [FJC]) 24 and 48 h post-bTBI. Neurological outcomes (beam balance and walking tests) and working memory (Morris water maze [MWM]) were assessed 2 weeks post-bTBI. Because impact TBI (i.e., non-blast TBI) is often associated with reduced cerebral perfusion and impaired cerebrovascular function in part because of the generation of reactive oxygen and nitrogen species such as peroxynitrite (ONOO−), the effects of the administration of the ONOO− scavenger, penicillamine methyl ester (PenME), on cerebral perfusion and cerebral vascular resistance were measured for 2 h post-bTBI. Mild bTBI resulted in reduced relative cerebral perfusion and MCA dilator responses to reduced intravascular pressure, increases in cerebral vascular resistance and in the numbers of FJC-positive cells in the brain, and significantly impaired working memory. PenME administration resulted in significant reductions in cerebral vascular resistance and a trend toward increased cerebral perfusion, suggesting that ONOO− may contribute to blast-induced cerebral vascular dysfunction. PMID:29160141

Protective effect of naringenin in experimental ischemic stroke: down-regulated NOD2, RIP2, NF-κB, MMP-9 and up-regulated claudin-5 expression.

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Bai, Xue; Zhang, Xiangjian; Chen, Linyu; Zhang, Jian; Zhang, Lan; Zhao, Xumeng; Zhao, Ting; Zhao, Yuan

2014-08-01

Inflammatory damage plays a pivotal, mainly detrimental role in cerebral ischemic pathogenesis and may represent a promising target for treatment. Naringenin (NG) has gained growing appreciation for its beneficial biological effects through its anti-inflammatory property. Whether this protective effect applies to cerebral ischemic injury, we therefore investigate the potential neuroprotective role of NG and the underlying mechanisms. Focal cerebral ischemia in male Sprague-Dawley rats was induced by permanent middle cerebral artery occlusion (pMCAO) and NG was pre-administered intragastrically once daily for four consecutive days before surgery. Neurological deficit, brain water content and infarct volume were measured at 24 h after stroke. Immunohistochemistry, Western blot and RT-qPCR were used to explore the anti-inflammatory potential of NG in the regulation of NOD2, RIP2 and NF-κB in ischemic cerebral cortex. Additionally, the activities of MMP-9 and claudin-5 were analyzed to detect NG's influence on blood-brain barrier. Compared with pMCAO and Vehicle groups, NG noticeably improved neurological deficit, decreased infarct volume and edema at 24 h after ischemic insult. Consistent with these results, our data also indicated that NG significantly downregulated the expression of NOD2, RIP2, NF-κB and MMP-9, and upregulated the expression of claudin-5 (P < 0.05). The results provided a neuroprotective profile of NG in cerebral ischemia, this effect was likely exerted by down-regulated NOD2, RIP2, NF-κB, MMP-9 and up-regulated claudin-5 expression.

Regional cerebral blood flow before and after vascular surgery in patients with transient ischemic attacks with 133-xenon inhalation tomography

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Vorstrup, S; Hemmingsen, Ralf; Lindewald, H

1982-01-01

Cerebral blood flow CBF was studied in 14 patients with transient ischemic attacks TIA and arteriosclerotic neck vessel disease. CBF was measured by a rapidly rotating single photon emission computerized tomograph using Xenon-133 inhalation. This method yields images of 3 brain slices depicting CBF...... with no abnormality on the CT-scan. The abnormal blood flow pattern was found to be unchanged after clinically successful reconstructive vascular surgery. This suggests the presence of irreversible ischemic tissue damage without gross emollition (incomplete infarction). It is concluded, that TIAs are often harmful...... events, as no less than 9 of the 14 patients studied had evidence of complete and/or incomplete infarction. Thorough examination and rational therapy should be instituted as soon as possible to prevent further ischemic lesions....

Purine Metabolism in Acute Cerebral Ischemia

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Ye. V. Oreshnikov

2008-01-01

Full Text Available Objective: to study the specific features of purine metabolism in clinically significant acute cerebral ischemia. Subjects and materials. Three hundred and fifty patients with the acutest cerebral ischemic stroke were examined. The parameters of gas and electrolyte composition, acid-base balance, the levels of malonic dialdehyde, adenine, guanine, hypox-anthine, xanthine, and uric acid, and the activity of xanthine oxidase were determined in arterial and venous bloods and spinal fluid. Results. In ischemic stroke, hyperuricemia reflects the severity of cerebral metabolic disturbances, hemodynamic instability, hypercoagulation susceptiility, and the extent of neurological deficit. In ischemic stroke, hyperuri-corachia is accompanied by the higher spinal fluid levels of adenine, guanine, hypoxanthine, and xanthine and it is an indirect indicator of respiratory disorders of central genesis, systemic acidosis, hypercoagulation susceptibility, free radical oxidation activation, the intensity of a stressor response to cerebral ischemia, cerebral metabolic disturbances, the depth of reduced consciousness, and the severity of neurological deficit. Conclusion. The high venous blood activity of xanthine oxidase in ischemic stroke is associated with the better neurological parameters in all follow-up periods, the better early functional outcome, and lower mortality rates. Key words: hyperuricemia, stroke, xanthine oxidase, uric acid, cerebral ischemia.

Effects of Remote Ischemic Conditioning Methods on Ischemia-Reperfusion Injury in Muscle Flaps: An Experimental Study in Rats

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Durdane Keskin

2017-09-01

Full Text Available Background The aim of this study was to investigate the effects of remote ischemic conditioning on ischemia-reperfusion injury in rat muscle flaps histopathologically and biochemically. Methods Thirty albino rats were divided into 5 groups. No procedure was performed in the rats in group 1, and only blood samples were taken. A gracilis muscle flap was elevated in all the other groups. Microclamps were applied to the vascular pedicle for 4 hours in order to achieve tissue ischemia. In group 2, no additional procedure was performed. In groups 3, 4, and 5, the right hind limb was used and 3 cycles of ischemia-reperfusion for 5 minutes each (total, 30 minutes was applied with a latex tourniquet (remote ischemic conditioning. In group 3, this procedure was performed before flap elevation (remote ischemic preconditoning. In group 4, the procedure was performed 4 hours after flap ischemia (remote ischemic postconditioning. In group 5, the procedure was performed after the flap was elevated, during the muscle flap ischemia episode (remote ischemic perconditioning. Results The histopathological damage score in all remote conditioning ischemia groups was lower than in the ischemic-reperfusion group. The lowest histopathological damage score was observed in group 5 (remote ischemic perconditioning. Conclusions The nitric oxide levels were higher in the blood samples obtained from the remote ischemic perconditioning group. This study showed the effectiveness of remote ischemic conditioning procedures and compared their usefulness for preventing ischemia-reperfusion injury in muscle flaps.

Effects of Remote Ischemic Conditioning Methods on Ischemia-Reperfusion Injury in Muscle Flaps: An Experimental Study in Rats.

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Keskin, Durdane; Unlu, Ramazan Erkin; Orhan, Erkan; Erkilinç, Gamze; Bogdaycioglu, Nihal; Yilmaz, Fatma Meric

2017-09-01

The aim of this study was to investigate the effects of remote ischemic conditioning on ischemia-reperfusion injury in rat muscle flaps histopathologically and biochemically. Thirty albino rats were divided into 5 groups. No procedure was performed in the rats in group 1, and only blood samples were taken. A gracilis muscle flap was elevated in all the other groups. Microclamps were applied to the vascular pedicle for 4 hours in order to achieve tissue ischemia. In group 2, no additional procedure was performed. In groups 3, 4, and 5, the right hind limb was used and 3 cycles of ischemia-reperfusion for 5 minutes each (total, 30 minutes) was applied with a latex tourniquet (remote ischemic conditioning). In group 3, this procedure was performed before flap elevation (remote ischemic preconditoning). In group 4, the procedure was performed 4 hours after flap ischemia (remote ischemic postconditioning). In group 5, the procedure was performed after the flap was elevated, during the muscle flap ischemia episode (remote ischemic perconditioning). The histopathological damage score in all remote conditioning ischemia groups was lower than in the ischemic-reperfusion group. The lowest histopathological damage score was observed in group 5 (remote ischemic perconditioning). The nitric oxide levels were higher in the blood samples obtained from the remote ischemic perconditioning group. This study showed the effectiveness of remote ischemic conditioning procedures and compared their usefulness for preventing ischemia-reperfusion injury in muscle flaps.

Magnetic resonance imaging in acute ischemic stroke

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Ohta, Kouichi [Mito Red Cross Hospital (Japan)

2000-01-01

This paper summarizes current MRI technology used in the diagnosis of acute cerebral infarction and discusses tasks for further improvement of MRI technology. First, the principles and methods of MRI imaging are described in terms of 1) diffusion-weighted imaging (DWI) and ADC maps, 2) perfusion imaging, 3) the fluid-attenuated inversion recovery (FLAIR) method, and 4) MR angiography (MRA). Then, the actual use of MRI in the early phase of ischemic cerebrovascular disorders is discussed focusing on general MRI procedures, cases in which an ischemic lesion dose not yield a high signal with DWI in the acute phase, and chronological changes in DWI signal strength and ADC. Third, chronological changes in acute cerebrovascular disorder in an animal model of local cerebral ischemia are summarized in terms of expansion of reduced ADC areas and ischemic penumbras in the acute phase of cerebral ischemia. Finally, chronological changes in acute ischemic disorders in patients with cerebrovascular disorders are assessed by reviewing the development of reduced ADC and expansion of DWI lesions. Whether MRI can identify cerebral tissues that can be rescued by the reperfusion method by examining the mismatchs between perfusion images and DWI, relative CBV, and ADC is also discussed. (K.H.)

Pathophysiological studies of experimental brain edema and cerebral ischemia using MRI/S

International Nuclear Information System (INIS)

Naruse, Shoji; Higuchi, Toshihiro; Horikawa, Yoshiharu; Tanaka, Chuzo; Hirakawa, Kimiyoshi

1987-01-01

Pathophysiological changes in experimental brain edema and cerebral ischemia were examined by the in vivo 1 H- and 31 P-NMR method. Two types of experimental brain edema were induced in rats by cold injury and by triethyltin (TET) intoxication. Experimental cerebral ischemia was induced in rats by the four-vessel occlusion method. During the course of these pathological conditions, the 1 H-MRIs and 31 P-NMR spectra were measured sequentially with a single NMR spectrometer (4.8 tesla, 9 cm bore magnet). In the cold-injury edema, high-intensity lesions were detected in the gray and white matters of the injured hemisphere by means of SE images with a long Te 3 hours after the injury. The intensity reached its maximum 16 to 24 hours after the injury, and then returned to normal 7 days later. These high-intensity lesions indicated an increase in the T2 value in the edematous tissue. There were no changes in the 31 P-NMR spectra during the course of edema formation and absorption. In the TET-induced edema, high-intensity lesions were also detected in the bilateral white matter by means of SE images with a long Te from the 3rd day up to the 7th day during the injection of TET. These high-intensity lesions subsided 42 days after the discontinuance of injecting TET. There were no changes in the 31 P-NMR spectra during the whole course of TET-induced edema. In the cerebral ischemia, no remarkable changes in the MRI were detected in either SE or IR images during the ischemic and recirculated periods. However, dynamic changes in the 31 P-NMR spectra were detected during the course of cerebral ischemia. In the pre-ischemic period, the peaks of the ATP, PCr, phosphodiesters (PDE), Pi, and phosphomonoesters (PME) were detected. After the induction of ischemia, the ATP and PCr peaks decreased, while one Pi peak increased rapidly. (J.P.N.)

Pathophysiological studies of experimental brain edema and cerebral ischemia using MRI/S

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Naruse, S; Higuchi, T; Horikawa, Y; Tanaka, C; Hirakawa, K

1987-02-01

Pathophysiological changes in experimental brain edema and cerebral ischemia were examined by the in vivo /sup 1/H- and /sup 31/P-NMR method. Two types of experimental brain edema were induced in rats by cold injury and by triethyltin (TET) intoxication. Experimental cerebral ischemia was induced in rats by the four-vessel occlusion method. During the course of these pathological conditions, the /sup 1/H-MRIs and /sup 31/P-NMR spectra were measured sequentially with a single NMR spectrometer (4.8 tesla, 9 cm bore magnet). In the cold-injury edema, high-intensity lesions were detected in the gray and white matters of the injured hemisphere by means of SE images with a long Te 3 hours after the injury. The intensity reached its maximum 16 to 24 hours after the injury, and then returned to normal 7 days later. These high-intensity lesions indicated an increase in the T2 value in the edematous tissue. There were no changes in the /sup 31/P-NMR spectra during the course of edema formation and absorption. In the TET-induced edema, high-intensity lesions were also detected in the bilateral white matter by means of SE images with a long Te from the 3rd day up to the 7th day during the injection of TET. These high-intensity lesions subsided 42 days after the discontinuance of injecting TET. There were no changes in the /sup 31/P-NMR spectra during the whole course of TET-induced edema. In the cerebral ischemia, no remarkable changes in the MRI were detected in either SE or IR images during the ischemic and recirculated periods. However, dynamic changes in the /sup 31/P-NMR spectra were detected during the course of cerebral ischemia. In the pre-ischemic period, the peaks of the ATP, PCr, phosphodiesters (PDE), Pi, and phosphomonoesters (PME) were detected. After the induction of ischemia, the ATP and PCr peaks decreased, while one Pi peak increased rapidly.

Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

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Chiva-Blanch, Gemma; Suades, Rosa; Crespo, Javier; Peña, Esther; Padró, Teresa; Jiménez-Xarrié, Elena; Martí-Fàbregas, Joan; Badimon, Lina

2016-01-01

Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke. Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells) were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls. Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions. Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger cerebral lesions

Microparticle Shedding from Neural Progenitor Cells and Vascular Compartment Cells Is Increased in Ischemic Stroke.

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Gemma Chiva-Blanch

Full Text Available Ischemic stroke has shown to induce platelet and endothelial microparticle shedding, but whether stroke induces microparticle shedding from additional blood and vascular compartment cells is unclear. Neural precursor cells have been shown to replace dying neurons at sites of brain injury; however, if neural precursor cell activation is associated to microparticle shedding, and whether this activation is maintained at long term and associates to stroke type and severity remains unknown. We analyzed neural precursor cells and blood and vascular compartment cells microparticle shedding after an acute ischemic stroke.Forty-four patients were included in the study within the first 48h after the onset of stroke. The cerebral lesion size was evaluated at 3-7 days of the stroke. Circulating microparticles from neural precursor cells and blood and vascular compartment cells (platelets, endothelial cells, erythrocytes, leukocytes, lymphocytes, monocytes and smooth muscle cells were analyzed by flow cytometry at the onset of stroke and at 7 and 90 days. Forty-four age-matched high cardiovascular risk subjects without documented vascular disease were used as controls.Compared to high cardiovascular risk controls, patients showed higher number of neural precursor cell- and all blood and vascular compartment cell-derived microparticles at the onset of stroke, and after 7 and 90 days. At 90 days, neural precursor cell-derived microparticles decreased and smooth muscle cell-derived microparticles increased compared to levels at the onset of stroke, but only in those patients with the highest stroke-induced cerebral lesions.Stroke increases blood and vascular compartment cell and neural precursor cell microparticle shedding, an effect that is chronically maintained up to 90 days after the ischemic event. These results show that stroke induces a generalized blood and vascular cell activation and the initiation of neuronal cell repair process after stroke. Larger

Effect of Ischemic Postconditioning and Atorvastatin in the Prevention of Remote Lung Reperfusion Injury

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Carlos Henrique Marques dos Santos

Full Text Available Abstract Objective: The aim of the present study was to evaluate the ability of ischemic postconditioning, atorvastatin and both associated to prevent or minimize reperfusion injury in the lung of rats subjected to ischemia and reperfusion by abdominal aortic clamping. Methods: We used 41 Wistar norvegic rats, which were distributed into 5 groups: ischemia and reperfusion (I/R, ischemic postcondictioning (IPC, postconditioning + atorvastatin (IPC+A, atorvastatin (A and SHAM. It was performed a medium laparotomy, dissection and isolation of the infra-renal abdominal aorta; except for the SHAM group, all the others were submitted to the aortic clamping for 70 minutes (ischemia and posterior clamp removal (reperfusion, 70 minutes. In the IPC and IPC+A groups, postconditioning was performed between the ischemia and reperfusion phases by four cycles of reperfusion and ischemia lasting 30 seconds each. In the IPC+A and A groups, preceding the surgical procedure, administration of 3.4 mg/day of atorvastatin was performed for seven days by gavage. After the surgical procedure, the right caudal lobe was removed from the lung for histological study, using tissue injury score ranging from grade 1 (normal tissue to grade 4 (intense lesion. Results: The mean lung injury was 3.6 in the I/R group, 1.6 in the IPC group, 1.2 in the IPC+A group, 1.2 in the A group, and 1 in the SHAM group (P<0.01. Conclusion: Ischemic postconditioning and atorvastatin were able to minimize lung reperfusion injury, alone or in combination.

Hypothermia therapy for newborns with hypoxic ischemic encephalopathy.

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Silveira, Rita C; Procianoy, Renato S

2015-01-01

Therapeutic hypothermia reduces cerebral injury and improves the neurological outcome secondary to hypoxic ischemic encephalopathy in newborns. It has been indicated for asphyxiated full-term or near-term newborn infants with clinical signs of hypoxic-ischemic encephalopathy (HIE). A search was performed for articles on therapeutic hypothermia in newborns with perinatal asphyxia in PubMed; the authors chose those considered most significant. There are two therapeutic hypothermia methods: selective head cooling and total body cooling. The target body temperature is 34.5 °C for selective head cooling and 33.5 °C for total body cooling. Temperatures lower than 32 °C are less neuroprotective, and temperatures below 30 °C are very dangerous, with severe complications. Therapeutic hypothermia must start within the first 6h after birth, as studies have shown that this represents the therapeutic window for the hypoxic-ischemic event. Therapy must be maintained for 72 h, with very strict control of the newborn's body temperature. It has been shown that therapeutic hypothermia is effective in reducing neurologic impairment, especially in full-term or near-term newborns with moderate hypoxic-ischemic encephalopathy. Therapeutic hypothermia is a neuroprotective technique indicated for newborn infants with perinatal asphyxia and hypoxic-ischemic encephalopathy. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Opposite effects of the gap junction blocker octanol on focal cerebral ischemia occluded for different durations.

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Ding, Wenting; Zhou, Lequan; Liu, Wei; Guan, Li; Li, Xiaoying; Liu, Haimei; Yan, Fuman; Xu, Jinwen; Zeng, Weiyong; Qiu, Min

2014-06-01

Protectants and executioners have been demonstrated to be used by gap junctions in focal cerebral ischemia. Certain researchers hypothesized that the opposite role of gap junctions may be associated with the injury extent, which has been demonstrated to be highly correlated with occlusion duration. In order to examine this hypothesis directly, the effects of octanol, a frequently used drug, were examined to investigate the role of gap junctions, in rats following middle cerebral artery occlusion (MCAO) for 30 min/2 h and 24 h reperfusion, respectively. Octanol significantly reduced the infarct volume following 2 h of occlusion concomitant with lower neurological deficits, whereas it enlarged the infarct volume following 30 min of occlusion. Consistently, octanol attenuated the number of transferase dUTP nick-end labeling (TUNEL) positive neurons in the hippocampal CA1 region following 2 h of occlusion, while opposite effects were observed for 30 min of occlusion. Further immunohistochemical studies demonstrated that the expression of B-cell leukemia-2 (Bcl-2, anti-apoptotic protein) was upregulated and that Bcl-2-associated X (Bax, proapoptotic protein) was downregulated following 2 h of occlusion in the octanol group compared with the ischemic group. Conversely, octanol downregulated the expression of the Bcl-2 protein concomitant with increased Bax protein following 30 min of occlusion. These results indicated that the gap junction blocker octanol can protect against ischemic injury following long-term occlusion, however, can aggravate ischemic injury following short-term occlusion.

Decimeter waves in complex treatment of patients with cerebral blood circulation insufficiency

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Strelkova, N.I.

Decimeter waves (DMW) were introduced into the therapeutic armamentarium relatively recently. The effect of DMW on the CNS was studied in the Division of Neurology at the Central Scientific Research Institute of Resort Science and Physiotherapy for a number of years on four groups of patients: (A) Parkinson's Disease Group, (B) patients with sequelae of open and closed craniocerebral injuries, (C) cerebral stroke patients basically of the ischemic type and (D) patients with transitory cerebral circulation disorders. The experience gained showed that the use of DMW improved cerebral circulation and aided in development of collateral circulation. It was found that in cases of tremor Parkinsonism and in epilepsy, DMW therapy should be applied to the collarbone area. Application of DMW in early stages of injury needs further study. Obviously, a single therapeutic intervention cannot provide complete recovery; a combined treatment must be applied, advisably under conditions of a resort spa. 11 references.

New asymptomatic ischemic lesions on diffusion-weighted imaging after cerebral angiography

International Nuclear Information System (INIS)

Shibazaki, Kensaku

2006-01-01

Conventional cerebral angiography (CAG) is relatively low risk for neurological complications. However, diffusion-weighted imaging (DWI) after CAG occasionally reveal an asymptomatic ischemic lesion on the brain. The aim of this study was to investigate the frequency of new asymptomatic or symptomatic DWI lesions after CAG and to clarify the factors associated with them. Fifty-six patients with acute ischemic stroke and transient ischemic attack were prospectively enrolled. Magnetic resonance imaging (MRI) studies including DWI were studied twice, within 48 hours before and after CAG. The following factors were assessed; age, gender, history of stroke, history of ischemic heart disease, vascular risk factors, National Institutes of Health Stroke Scale (NIHSS) score on admission, stroke subtype, treatment before stroke or transient ischemic attack (TIA) (antiplatelets or warfarin), approach for catheters (transbrachial or femoral artery), amount of contrast medium used, length of the angiographic procedure, and fluoroscophy time. We divided the patients into two groups according to the presence of new DWI lesions after CAG; Positive group had new DWI lesions, whereas the Negative group had none. After CAG, no patients had new neurological deficits. New asymptomatic DWI lesions were observed in 24 patients (42.9%). The significant differences observed between two groups were as follows; age (69.8±11.3 for the Positive group versus 61.9±11.3 for the Negative group, p=0.043), female (54% versus 28%, p=0.048), non-small vessel occlusion (100% versus 66%, p=0.009), catheter approach for transfemoral artery (63% versus 13%, p<0.001), mean length of the angiographic procedure (63.1±21.6 min versus 43.7±14.2 min, p<0.001), mean fluoroscopy time (26.5±13.0 min versus 14.9±5.9 mm, p<0.001). Sensitivity and specificity analysis to discriminate the positive and negative groups revealed 17 minutes to be the critical threshold point (sensitivity 66.6% and specificity 68

Protective Effect of Klotho against Ischemic Brain Injury Is Associated with Inhibition of RIG-I/NF-κB Signaling

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Hong-Jing Zhou

2018-01-01

Full Text Available Aging is the greatest independent risk factor for the occurrence of stroke and poor outcomes, at least partially through progressive increases in oxidative stress and inflammation with advanced age. Klotho is an antiaging gene, the expression of which declines with age. Klotho may protect against neuronal oxidative damage that is induced by glutamate. The present study investigated the effects of Klotho overexpression and knockdown by an intracerebroventricular injection of a lentiviral vector that encoded murine Klotho (LV-KL or rat Klotho short-hairpin RNA (LV-KL shRNA on cerebral ischemia injury and the underlying anti-neuroinflammatory mechanism. The overexpression of Klotho induced by LV-KL significantly improved neurobehavioral deficits and increased the number of live neurons in the hippocampal CA1 and caudate putamen subregions 72 h after cerebral hypoperfusion that was induced by transient bilateral common carotid artery occlusion (2VO in mice. The overexpression of Klotho significantly decreased the immunoreactivity of glial fibrillary acidic protein and ionized calcium binding adaptor molecule-1, the expression of retinoic-acid-inducible gene-I, the nuclear translocation of nuclear factor-κB, and the production of proinflammatory cytokines (tumor necrosis factor α and interleukin-6 in 2VO mice. The knockdown of Klotho mediated by LV-KL shRNA in the brain exacerbated neurological dysfunction and cerebral infarct after 22 h of reperfusion following 2 h middle cerebral artery occlusion in rats. These findings suggest that Klotho itself or enhancers of Klotho may compensate for its aging-related decline, thus providing a promising therapeutic approach for acute ischemic stroke during advanced age.

Omega-3 fatty acids protect the brain against ischemic injury by activating Nrf2 and upregulating heme oxygenase 1.

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Zhang, Meijuan; Wang, Suping; Mao, Leilei; Leak, Rehana K; Shi, Yejie; Zhang, Wenting; Hu, Xiaoming; Sun, Baoliang; Cao, Guodong; Gao, Yanqin; Xu, Yun; Chen, Jun; Zhang, Feng

2014-01-29

Ischemic stroke is a debilitating clinical disorder that affects millions of people, yet lacks effective neuroprotective treatments. Fish oil is known to exert beneficial effects against cerebral ischemia. However, the underlying protective mechanisms are not fully understood. The present study tests the hypothesis that omega-3 polyunsaturated fatty acids (n-3 PUFAs) attenuate ischemic neuronal injury by activating nuclear factor E2-related factor 2 (Nrf2) and upregulating heme oxygenase-1 (HO-1) in both in vitro and in vivo models. We observed that pretreatment of rat primary neurons with docosahexaenoic acid (DHA) significantly reduced neuronal death following oxygen-glucose deprivation. This protection was associated with increased Nrf2 activation and HO-1 upregulation. Inhibition of HO-1 activity with tin protoporphyrin IX attenuated the protective effects of DHA. Further studies showed that 4-hydroxy-2E-hexenal (4-HHE), an end-product of peroxidation of n-3 PUFAs, was a more potent Nrf2 inducer than 4-hydroxy-2E-nonenal derived from n-6 PUFAs. In an in vivo setting, transgenic mice overexpressing fatty acid metabolism-1, an enzyme that converts n-6 PUFAs to n-3 PUFAs, were remarkably resistant to focal cerebral ischemia compared with their wild-type littermates. Regular mice fed with a fish oil-enhanced diet also demonstrated significant resistance to ischemia compared with mice fed with a regular diet. As expected, the protection was associated with HO-1 upregulation, Nrf2 activation, and 4-HHE generation. Together, our data demonstrate that n-3 PUFAs are highly effective in protecting the brain, and that the protective mechanisms involve Nrf2 activation and HO-1 upregulation by 4-HHE. Further investigation of n-3 PUFA neuroprotective mechanisms may accelerate the development of stroke therapies.

Enhanced expressions of microvascular smooth muscle receptors after focal cerebral ischemia occur via the MAPK MEK/ERK pathway

DEFF Research Database (Denmark)

Maddahi, A.; Edvinsson, L.

2008-01-01

), the enhanced vascular receptor expression, and attenuated the cerebral infarct and improved neurology score. CONCLUSION: Our results show that MCAO results in upregulation of cerebrovascular ETB, AT1 and 5-HT1B receptors. Blockade of this event with a MEK1 inhibitor as late as 6 h after the insult reduced...... the role of the MEK/ERK pathway in receptor expression following ischemic brain injury using the specific MEK1 inhibitor U0126. METHODS AND RESULT: Rats were subjected to a 2-h middle cerebral artery occlusion (MCAO) followed by reperfusion for 48-h and the ischemic area was calculated. The expression...... of phosphorylated ERK1/2 and Elk-1, and of endothelin ETA and ETB, angiotensin AT1, and 5-hydroxytryptamine 5-HT1B receptors were analyzed with immunohistochemistry using confocal microscopy in cerebral arteries, microvessels and in brain tissue. The expression of endothelin ETB receptor was analyzed...

Transient cerebral ischemia induces albumin expression in microglia only in the CA1 region of the gerbil hippocampus.

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Park, Joon Ha; Park, Jin-A; Ahn, Ji Hyeon; Kim, Yang Hee; Kang, Il Jun; Won, Moo-Ho; Lee, Choong-Hyun

2017-07-01

Albumin, the most abundant plasma protein, is known to exhibit a neuroprotective effect in animal models of focal and global cerebral ischemia. In the present study, the expression and immunoreactivity of albumin was examined in the hippocampus following 5 min of transient cerebral ischemia in gerbils. Albumin immunoreactivity was observed in microglia of the CA1 hippocampal region 2 days post‑ischemic insult, and it was significantly increased at 4 days following ischemia-reperfusion. In addition, at 4 days post‑ischemic insult, albumin‑immunoreactive microglia were abundant in the stratum pyramidale of the CA1 region. The present results demonstrated that albumin was newly expressed post‑injury in microglia in the CA1 region, suggesting ischemia‑induced neuronal loss. Albumin expression may therefore be associated with ischemia‑induced delayed neuronal death in the CA1 region following transient cerebral ischemia.

Neuroprotective Efficacy of an Aminopropyl Carbazole Derivative P7C3-A20 in Ischemic Stroke.

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Wang, Shu-Na; Xu, Tian-Ying; Wang, Xia; Guan, Yun-Feng; Zhang, Sai-Long; Wang, Pei; Miao, Chao-Yu

2016-09-01

NAMPT is a novel therapeutic target of ischemic stroke. The aim of this study was to investigate the effect of a potential NAMPT activator, P7C3-A20, an aminopropyl carbazole derivative, on ischemic stroke. In vitro study, neuron protection effect of P7C3-A20 was investigated by co-incubation with primary neurons subjected to oxygen-glucose deprivation (OGD) or oxygen-glucose deprivation/reperfusion (OGD/R) injury. In vivo experiment, P7C3-A20 was administrated in middle cerebral artery occlusion (MCAO) rats and infarct volume was examined. Lastly, the brain tissue nicotinamide adenine dinucleotide (NAD) levels were detected in P7C3-A20 treated normal or MCAO mice. Cell viability, morphology, and Tuj-1 staining confirmed the neuroprotective effect of P7C3-A20 in OGD or OGD/R model. P7C3-A20 administration significantly reduced cerebral infarction in MCAO rats. Moreover, brain NAD levels were elevated both in normal and MCAO mice after P7C3-A20 treatment. P7C3-A20 has neuroprotective effect in cerebral ischemia. The study contributes to the development of NAMPT activators against ischemic stroke and expands the horizon of the neuroprotective effect of aminopropyl carbazole chemicals. © 2016 John Wiley & Sons Ltd.

Cerebral microangiopathies

International Nuclear Information System (INIS)

Linn, Jennifer

2011-01-01

Cerebral microangiopathies are a very heterogenous group of diseases characterized by pathological changes of the small cerebral vessels. They account for 20 - 30 % of all ischemic strokes. Degenerative microangiopathy and sporadic cerebral amyloid angiography represent the typical acquired cerebral microangiopathies, which are found in over 90 % of cases. Besides, a wide variety of rare, hereditary microangiopathy exists, as e.g. CADASIL (Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy), Fabrys disease and MELAS syndrome (Mitochondrial myopathy, Encephalopathy, Lactic Acidosis, and Stroke-like episodes). (orig.)

Neurosteroids and Ischemic Stroke: Progesterone a Promising Agent in Reducing the Brain Injury in Ischemic Stroke.

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Andrabi, Syed Suhail; Parvez, Suhel; Tabassum, Heena

2017-01-01

Progesterone (P4), a well-known neurosteroid, is produced by ovaries and placenta in females and by adrenal glands in both sexes. Progesterone is also synthesized by central nervous system (CNS) tissues to perform various vital neurological functions in the brain. Apart from performing crucial reproductive functions, it also plays a pivotal role in neurogenesis, regeneration, cognition, mood, inflammation, and myelination in the CNS. A substantial body of experimental evidence from animal models documents the neuroprotective role of P4 in various CNS injury models, including ischemic stroke. Extensive data have revealed that P4 elicits neuroprotection through multiple mechanisms and systems in an integrated manner to prevent neuronal and glial damage, thus reducing mortality and morbidity. Progesterone has been described as safe for use at the clinical level through different routes in several studies. Data regarding the neuroprotective role of P4 in ischemic stroke are of great interest due to their potential clinical implications. In this review, we succinctly discuss the biosynthesis of P4 and distribution of P4 receptors (PRs) in the brain. We summarize our work on the general mechanisms of P4 mediated via the modulation of different PR and neurotransmitters. Finally, we describe the neuroprotective mechanisms of P4 in ischemic stroke models and related clinical prospects.

[Retrospective analysis of risk factors in 900 patients with ischemic cerebral stroke of wind-phlegm collateral obstruction syndrome and qi deficiency blood stasis syndrome in Wuhan District].

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Qiu, Xin; Wang, Kai-xin; Chen, Guo-hua

2011-11-01

To analyze the correlation between risk factors and ischemic cerebral stroke of wind-phlegm collateral obstruction syndrome and qi deficiency blood stasis syndrome. Totally 900 patients of the two syndrome types were recruited. Risk factors correlated to ischemic cerebral stroke such as gender, age, time of onset, site of infarction, tongue proper, tongue fur, pulse picture, hypertension, diabetes, past stroke history, hyperlipidemia, hematocrit, smoking, drinking, genetic factor, blood type, complications were analyzed using Chi-square test and non-conditional Logistic regression analysis. Statistical significance existed between the two syndrome types in age (X2 = 8.2392, P = 0.0413), hyperlipidemia (X2 = 4.8386, P = 0.0278), tongue proper (X2 = 7.9470, P = 0.0048), and tongue fur (X2 = 4.3298, P = 0.0375). Statistical significance existed between the two syndrome types in hyperlipidemia, tongue proper, and tongue fur, and their OR value was 0.699 (P = 0.0282), 0.332 (P =0.0071), and 0.667 (P = 0.0382) respectively. The OR value of the past stroke history was 3.226 (P = 0.0314), that of complications 0.203 (P = 0.0705), and that of anterior circulation infarction 0.214 (P = 0.0098). Among different ages groups, the constituent ratio of qi deficiency blood stasis syndrome was obviously higher than that of wind-phlegm collateral obstruction syndrome. Besides, patients of qi deficiency blood stasis syndrome were liable to suffer from hyperlipidemia, anterior circulation infarction, and complications. The age, blood lipid levels, site of infarction, complications are closely correlated with Chinese syndrome types of ischemic cerebral stroke, which can provide objective indices for typing ischemic cerebral stroke.

Nrdp1 Increases Ischemia Induced Primary Rat Cerebral Cortical Neurons and Pheochromocytoma Cells Apoptosis Via Downregulation of HIF-1α Protein

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Yuan Zhang

2017-09-01

Full Text Available Neuregulin receptor degradation protein-1 (Nrdp1 is an E3 ubiquitin ligase that targets proteins for degradation and regulates cell growth, apoptosis and oxidative stress in various cell types. We have previously shown that Nrdp1 is implicated in ischemic cardiomyocyte death. In this study, we investigated the change of Nrdp1 expression in ischemic neurons and its role in ischemic neuronal injury. Primary rat cerebral cortical neurons and pheochromocytoma (PC12 cells were infected with adenoviral constructs expressing Nrdp1 gene or its siRNA before exposing to oxygen-glucose deprivation (OGD treatment. Our data showed that Nrdp1 was upregulated in ischemic brain tissue 3 h after middle cerebral artery occlusion (MCAO and in OGD-treated neurons. Of note, Nrdp1 overexpression by Ad-Nrdp1 enhanced OGD-induced neuron apoptosis, while knockdown of Nrdp1 with siRNA attenuated this effect, implicating a role of Nrdp1 in ischemic neuron injury. Moreover, Nrdp1 upregulation is accompanied by increased protein ubiquitylation and decreased protein levels of ubiquitin-specific protease 8 (USP8 in OGD-treated neurons, which led to a suppressed interaction between USP8 and HIF-1α and subsequently a reduction in HIF-1α protein accumulation in neurons under OGD conditions. In conclusion, our data support an important role of Nrdp1 upregulation in ischemic neuronal death, and suppressing the interaction between USP8 and HIF-1α and consequently the hypoxic adaptive response of neurons may account for this detrimental effect.

Cerebrovascular ischemic protection by pre- and post-conditioning

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Jeffrey M Gidday

2015-01-01

Full Text Available Stroke and cardiac arrest involve injury to all the brain′s resident cells and their respective progenitors, including neurons, all glial subtypes, vascular smooth muscle, vascular endothelium, and pericytes, resulting either in the death of the individual or in a lesion that likely manifests as long-term impairments across a number of cognitive and functional domains. Thousands of studies in experimental animals and results from a few clinical trials in humans have demonstrated that the mechanisms responsible for ischemic brain injury can be blocked or slowed by survival-enhancing epigenetic responses induced by "conditioning" the brain with a stress stimulus paradigm before or even after ictus. The resultant reduction in lesion size and functional deficits are often termed endogenous "neuroprotection," but this in fact involves cytoprotective responses on the part of all the aforementioned resident brain cells and the circulating immune cells as well. The present review will summarize findings demonstrating conditioning-induced protection of the cerebral vasculature, that in turn manifests as reductions in vascularly targeted inflammatory responses; less endothelial injury and improvements in structural integrity of the circulation across all levels of organization; enhanced perfusion with less thrombosis; reductions in vascular dysregulation and reactivity impairments; and, over the longer term, more robust angiogenesis and vascular remodeling. Advancing the mechanistic basis for these innately vasculoprotective phenotypes may provide therapeutic targets for limiting cerebral circulatory injury and dysfunction following stroke and cardiac arrest.

Acupuncture regulates the glucose metabolism in cerebral functional regions in chronic stage ischemic stroke patients---a PET-CT cerebral functional imaging study

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Huang Yong

2012-06-01

Full Text Available Abstract Background Acupuncture has been applied to aid in the recovery of post-stroke patients, but its mechanism is unclear. This study aims to analyze the relationship between acupuncture and glucose metabolism in cerebral functional regions in post-stroke patients using 18 FDG PET-CT techniques. Forty-three ischemic stroke patients were randomly divided into 5 groups: the Waiguan (TE5 needling group, the TE5 sham needling group, the sham point needling group, the sham point sham needling group and the non-needling group. Cerebral functional images of all patients were then acquired using PET-CT scans and processed by SPM2 software. Results Compared with the non-needling group, sham needling at TE5 and needling/sham needling at the sham point did not activate cerebral areas. However, needling at TE5 resulted in the activation of Brodmann Area (BA 30. Needling/sham needling at TE5 and needling at the sham point did not deactivate any cerebral areas, whereas sham needling at the sham point led to deactivation in BA6. Compared with sham needling at TE5, needling at TE5 activated BA13, 19 and 47 and did not deactivate any areas. Compared with needling at the sham point, needling at TE5 had no associated activation but a deactivating effect on BA9. Conclusion Needling at TE5 had a regulating effect on cerebral functional areas shown by PET-CT, and this may relate to its impact on the recovery of post-stroke patients.

Upregulation of NOX2 and NOX4 Mediated by TGF-β Signaling Pathway Exacerbates Cerebral Ischemia/Reperfusion Oxidative Stress Injury

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Zheng Lou

2018-04-01

Full Text Available Background/Aims: Ischemic stroke is still one of the leading debilitating diseases with high morbidity and mortality. NADPH oxidase (NOX-derived reactive oxygen species (ROS play an important role in cerebral ischemia/reperfusion (I/R injury. However, the mechanism underlying the regulation of ROS generation is still not fully elucidated. This study aims to explore the role of transforming growth beta (TGF-β signals in ROS generation. Methods: Sprague–Dawley rats were subjected to I/R injury, and PC-12 cells were challenged by hypoxia/reoxygenation (H/R and/or treated with activin receptor-like kinase (ALK5 inhibitor Sb505124 or siRNA against ALK5. Brain damage was evaluated using neurological scoring, triphenyl tetrazolium chloride staining, hematoxylin and eosin staining, infarct volume measurement, TUNEL staining, and caspase-3 activity measurement. Expression of TGF-β and oxidative stress-related genes was analyzed by real-time polymerase chain reaction and Western blot; NOX activity and ROS level were measured using spectrophotometry and fluorescence microscopy, respectively. Results: I/R contributed to severe brain damage (impaired neurological function, brain infarction, tissue edema, apoptosis, TGF-β signaling activation (upregulation of ALK5, phosphorylation of SMAD2/3 and oxidative stress (upregulation of NOX2/4, rapid release of ROS [oxidative burst]. However, Sb505124 significantly reversed these alterations and protected rats against I/R injury. As in the animal results, H/R also contributed to TGF-β signaling activation and oxidative stress. Likewise, the inhibition of ALK5 or ALK5 knockdown significantly reversed these alterations in PC-12 cells. Other than ALK5 knockdown, ALK5 inhibition had no effect on the expression of ALK5 in PC-12 cells. Conclusions: Our studies demonstrated that TGF-β signaling activation is involved in the regulation of NOX2/NOX4 expression and exacerbates cerebral I/R injury.

Electroacupuncture pretreatment induces tolerance against focal cerebral ischemia through activation of canonical Notch pathway

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Zhao Yu

2012-09-01

Full Text Available Abstract Background Electroacupuncture (EA pretreatment can induce the tolerance against focal cerebral ischemia. However, the underlying mechanisms have not been fully understood. Emerging evidences suggest that canonical Notch signaling may be involved in ischemic brain injury. In the present study, we tested the hypothesis that EA pretreatment-induced tolerance against focal cerebral ischemia is mediated by Notch signaling. Results EA pretreatment significantly enhanced Notch1, Notch4 and Jag1 gene transcriptions in the striatum, except Notch1 intracellular domain level, which could be increased evidently by ischemia. After ischemia and reperfusion, Hes1 mRNA and Notch1 intracellular domain level in ischemic striatum in EA pretreatment group were increased and reached the peak at 2 h and 24 h, respectively, which were both earlier than the peak achieved in control group. Intraventricular injection with the γ-secretase inhibitor MW167 attenuated the neuroprotective effect of EA pretreatment. Conclusions EA pretreatment induces the tolerance against focal cerebral ischemia through activation of canonical Notch pathway.

Retinal ischemic injury rescued by sodium 4-phenylbutyrate in a rat model.

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Jeng, Yung-Yue; Lin, Nien-Ting; Chang, Pen-Heng; Huang, Yuan-Ping; Pang, Victor Fei; Liu, Chen-Hsuan; Lin, Chung-Tien

2007-03-01

Retinal ischemia is a common cause of visual impairment for humans and animals. Herein, the neuroprotective effects of phenylbutyrate (PBA) upon retinal ischemic injury were investigated using a rat model. Retinal ganglion cells (RGCs) were retrograde labeled with the fluorescent tracer fluorogold (FG) applied to the superior collicoli of test Sprague-Dawley rats. High intraocular pressure and retinal ischemia were induced seven days subsequent to such FG labeling. A dose of either 100 or 400 mg/kg PBA was administered intraperitoneally to test rats at two time points, namely 30 min prior to the induction of retinal ischemia and 1 h subsequent to the cessation of the procedure inducing retinal ischemia. The test-rat retinas were collected seven days subsequent to the induction of retinal ischemia, and densities of surviving RGCs were estimated by counting FG-labeled RGCs within the retina. Histological analysis revealed that ischemic injury caused the loss of retinal RGCs and a net decrease in retinal thickness. For PBA-treated groups, almost 100% of the RGCs were preserved by a pre-ischemia treatment with PBA (at a dose of either 100 or 400 mg/kg), while post-ischemia treatment of RGCs with PBA did not lead to the preservation of RGCs from ischemic injury by PBA as determined by the counting of whole-mount retinas. Pre-ischemia treatment of RGCs with PBA (at a dose of either 100 or 400 mg/kg) significantly reduced the level of ischemia-associated loss of thickness of the total retina, especially the inner retina, and the inner plexiform layer of retina. Besides, PBA treatment significantly reduced the ischemia-induced loss of cells in the ganglion-cell layer of the retina. Taken together, these results suggest that PBA demonstrates a marked neuroprotective effect upon high intraocular pressure-induced retinal ischemia when the PBA is administered prior to ischemia induction.

Human-derived physiological heat shock protein 27 complex protects brain after focal cerebral ischemia in mice.

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Shinichiro Teramoto

Full Text Available Although challenging, neuroprotective therapies for ischemic stroke remain an interesting strategy for countering ischemic injury and suppressing brain tissue damage. Among potential neuroprotective molecules, heat shock protein 27 (HSP27 is a strong cell death suppressor. To assess the neuroprotective effects of HSP27 in a mouse model of transient middle cerebral artery occlusion, we purified a "physiological" HSP27 (hHSP27 from normal human lymphocytes. hHSP27 differed from recombinant HSP27 in that it formed dimeric, tetrameric, and multimeric complexes, was phosphorylated, and contained small amounts of αβ-crystallin and HSP20. Mice received intravenous injections of hHSP27 following focal cerebral ischemia. Infarct volume, neurological deficit scores, physiological parameters, and immunohistochemical analyses were evaluated 24 h after reperfusion. Intravenous injections of hHSP27 1 h after reperfusion significantly reduced infarct size and improved neurological deficits. Injected hHSP27 was localized in neurons on the ischemic side of the brain. hHSP27 suppressed neuronal cell death resulting from cytochrome c-mediated caspase activation, oxidative stress, and inflammatory responses. Recombinant HSP27 (rHSP27, which was artificially expressed and purified from Escherichia coli, and dephosphorylated hHSP27 did not have brain protective effects, suggesting that the phosphorylation of hHSP27 may be important for neuroprotection after ischemic insults. The present study suggests that hHSP27 with posttranslational modifications provided neuroprotection against ischemia/reperfusion injury and that the protection was mediated through the inhibition of apoptosis, oxidative stress, and inflammation. Intravenously injected human HSP27 should be explored for the treatment of acute ischemic strokes.

Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents

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Eisenmann, Eric D.; Rorabaugh, Boyd R.; Zoladz, Phillip R.

2016-01-01

Cardiovascular disease is the largest cause of mortality worldwide, and stress is a significant contributor to the development of cardiovascular disease. The relationship between acute and chronic stress and cardiovascular disease is well-evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia-reperfusion injury. Conversely, chronic stress is arrythmogenic and incr...

(1)H NMR-based metabonomics revealed protective effect of Naodesheng bioactive extract on ischemic stroke rats.

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Luo, Lan; Zhen, Lifeng; Xu, Yatao; Yang, Yongxia; Feng, Suxiang; Wang, Shumei; Liang, Shengwang

2016-06-20

Stroke is a leading cause of death and disability in the world. However, current therapies are limited. Naodesheng, a widely used traditional Chinese medicine prescription, has shown a good clinical curative effect on ischemic stroke. Also, Naodesheng has been suggested to have neuroprotective effect on focal cerebral ischemia rats, but the underlying molecular mechanism remains unclear. The present study was designed to evaluate the effect of Naodesheng bioactive extract on the metabolic changes in brain tissue, plasma and urine induced by cerebral ischemia perfusion injury, and explore the possible metabolic mechanisms by using a (1)H NMR-based metabonomics approach. A middle cerebral artery occlusion rat model was established and confirmed by the experiments of neurobehavioral abnormality evaluation, brain tissue TTC staining and pathological examination. The metabolic changes in brain tissue, plasma and urine were then assessed by a (1)H NMR technique combined with multivariate statistical analysis method. These NMR data showed that cerebral ischemia reperfusion induced great metabolic disorders in brain tissue, plasma and urine metabolisms. However, Naodesheng bioactive extract could reverse most of the imbalanced metabolites. Meanwhile, it was found that both the medium and high dosages of Naodesheng bioactive extract were more effective on the metabolic changes than the low dosage, consistent with histopathological assessments. These results revealed that Naodesheng had protective effect on ischemic stroke rats and the underlying mechanisms involved multiple metabolic pathways, including energy metabolism, amino acid metabolism, oxidative stress and inflammatory injury. The present study could provide evidence that metabonomics revealed its capacity to evaluate the holistic efficacy of traditional Chinese medicine and explore the underlying mechanisms. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Magnetic resonance imaging in acute stage of cerebral ischemia

International Nuclear Information System (INIS)

Yamagata, Sen; Kikuchi, Haruhiko; Ihara, Ikuo

1986-01-01

The value of the nuclear magnetic resonance image (MRI) was investigated in the acute stage of experimental cerebral ischemia. The MRI system employed was designed for clinical use, and the superconducting magnet was operated at a field strength of 1.5 tesla. Ischemic insult was made by transorbital occlusion of the middle cerebral artery (MCA) permanently in 4 cats and temporarily in 2 cats. After MCA occlusion the regional cerebral blood flow (rCBF) was measured on the affected cortex, and 5 cats with rCBF below 10 ml/100 g/min and one with rCBF over 15 ml/100 g/min were studied. In the permanent occlusion group, MRI was performed every 2 hours from 4 to 12 hours after MCA occlusion and another MRI was carried out 20 min after gadolinium-diethylenetriamine-pentaacetic acid (Gd-DTPA) intravenous administration. The earliest changes were found 6 to 8 hours after MCA occlusion on the spin echo image (repetition time = 1.4 sec, echo time = 70 msec) in 3 cats with severe ischemia. It was postulated that the ischemic lesion could be depicted less than 6 hours on more T 2 -weighted images. The increased intensity area was markedly enhanced with Gd-DTPA 12 hours after occlusion. In the recirculation group, the increased intensity area was observed on enhanced MRI in a cat with recirculation as early as one hour after MCA occlusion, although it was not found on the plain MRI. In the other cat with recirculation after 2 hours' occlusion, definite lesion was found in all parameter images without enhancement. The results suggest that changes in cerebral ischemia can be obtained on the MRI earlier than X-ray computed tomography, and that it may be possible to determine the severity of the ischemic brain injury by the MRI findings. (author)

Intravital and post-mortem CT examinations of cerebral gunshot injuries

International Nuclear Information System (INIS)

Schumacher, M.; Oehmichen, M.; Koenig, H.G.; Einighammer, H.; Koeln Univ.; Tuebingen Univ.; Duesseldorf Univ.

1983-01-01

The value of CT was assessed in 24 patients who died of cerebral gun-shot injuries and in two patients with more recent injuries in order to reconstruct the mode of injury and for adding forensic information. The post-mortem and intravital appearances are described and are compared with ultrasound rotation compound scans of the isolated brains. CT showed good agreement with pathological findings. Ultrasound produced images with an accuracy between CT and photographs of the brain specimen. Both methods are regarded as valuable additions to the pathological and forensic information concerning gunshot injuries. (orig.) [de

Estudo de fatores clínicos preditivos para crises epilépticas após acidente vascular cerebral isquêmico Preditive clinical factors for epileptic seizures after ischemic stroke

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Marcia Maiumi Fukujima

1996-06-01

Full Text Available Apresentamos aspectos clínicos de 35 pacientes com acidente vascular cerebral isquêmico que evoluíram com crises epilépticas (Grupo 1, comparando-os a 35 pacientes com AVCI sem crises epilépticas (Grupo 2. A comparação das idades entre os grupos não mostrou diferença significante. O sexo masculino e a raça branca predominaram em ambos os grupos. Diabetes melito, hipertensão arterial, ataque isquêmico transitório, acidente vascular cerebral pregresso, enxaqueca, doença de Chagas, embolia cerebral cardiogênica e uso de anticoncepcional oral não diferiram significantemente entre os grupos. Tabagismo e etilismo foram significantemente mais freqüentes no Grupo 1 (pPreditive clinical factors for epileptic seizures after ischemic stroke. Clinical features of 35 patients with ischemic stroke who developed epilepsy (Group 1 were compared with those of 35 patients with ischemic stroke without epilepsy (Group 2. The age of the patients did not differ between the groups. There were more men than women and more white than other races in both groups. Diabetes melitus, hypertension, transient ischemic attack, previous stroke, migraine, Chagas disease, cerebral embolism of cardiac origin and use of oral contraceptive did not differ between the groups. Smokers and alcohol users were more frequent in Group 1 (p<0,05. Most patients of Group 1 presented with hemiparesis; none presented cerebellar or brainstem involvement. Perhaps strokes in smokers have some different aspects, that let them more epileptogenic than in non smokers.

Noninvasive quantitative assessment of cerebral blood flow (CBF) using Tc-99m ECD SPECT with adjunctive radionuclide angiography in ischemic stroke

International Nuclear Information System (INIS)

Yim, Jun Sung; Choi, Yun Young; Kim, Seung Hyun; Kim, Myung Ho; Cho, Suk Shin

1999-01-01

Quantitative CBF measurements are essential for diagnosing ischemic lesion, evaluating the therapeutic effects and predicting the prognosis of cerebral ischemia. Even though several methods have been introduced, these techniques are too cumbersome and invasive to be applied to routine studies. In this study, a non-invasive simple method for the quantitative angiography. Fifteen normal controls and 27 patients with unilateral carotid ischemic stoke were selected. Brain perfusion index (BPI) of each hemisphere was measured in each subject by acquisition of serial radionuclide angiography after injection of 20mCi of Tc-99m ECD. With Lassen's correction algorithm of curve-linear relationship between the brain activity and blood flow, rCBF on transaxial SPECT slice corresponding with MRI lesion sites (ischemic core, border zone and contralateral mirror locus) were calculated. BPI values for normal controls showed a significant negative correlation with advantage age (r=-0.64, p=0.021) and hemisphric BPI were 11.02±1.6 and 7.8±1.4 for normal controls and patient, respectively. Significant differences were observed between two groups (p=0.0012). rCBF obtained from core zone (12±2.5 ml/100/min), boneder zone (29.2±8.1) and contralateral mirror locus (52.1±15.1) were clearly defined in each subject of patient group. Measurement of BPI and rCBF using Tc-99m ECD SPECT with adjunctive radionuclide angiography could be an useful, simple and non-invasive method in evaluation of the cerebral flood in the ischemic stroke

Cerebral perfusion changes in traumatic diffuse brain injury. IMP SPECT studies

International Nuclear Information System (INIS)

Ito, Hiroshi; Kawashima, Ryuta; Fukuda, Hiroshi; Ishii, Kiyoshi; Onuma, Takehide.

1997-01-01

Diffuse brain injury (DBI) is characterized by axonal degeneration and neuronal damage which cause diffuse brain atrophy. We have investigated the time course of abnormalities in cerebral perfusion distribution in cases of DBI by using Iodine-123-IMP SPECT, and the relationship to the appearance of diffuse brain atrophy. SPECT scans were performed on eight patients with diffuse brain injury due to closed cranial trauma in acute and chronic stages. All patients showed abnormalities in cerebral perfusion with decreases in perfusion, even in non-depicted regions on MRI, and the affected areas varied throughout the period of observation. Diffuse brain atrophy appeared in all patients. In some patients, diffuse brain atrophy was observed at or just after the time when the maximum number of lesions on SPECT were seen. The abnormalities in cerebral perfusion in cases of DBI might therefore be related to axonal degeneration and neuronal damage which causes diffuse brain atrophy. (author)

Evidence that the EphA2 receptor exacerbates ischemic brain injury.

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John Thundyil

Full Text Available Ephrin (Eph signaling within the central nervous system is known to modulate axon guidance, synaptic plasticity, and to promote long-term potentiation. We investigated the potential involvement of EphA2 receptors in ischemic stroke-induced brain inflammation in a mouse model of focal stroke. Cerebral ischemia was induced in male C57Bl6/J wild-type (WT and EphA2-deficient (EphA2(-/- mice by middle cerebral artery occlusion (MCAO; 60 min, followed by reperfusion (24 or 72 h. Brain infarction was measured using triphenyltetrazolium chloride staining. Neurological deficit scores and brain infarct volumes were significantly less in EphA2(-/- mice compared with WT controls. This protection by EphA2 deletion was associated with a comparative decrease in brain edema, blood-brain barrier damage, MMP-9 expression and leukocyte infiltration, and higher expression levels of the tight junction protein, zona occludens-1. Moreover, EphA2(-/- brains had significantly lower levels of the pro-apoptotic proteins, cleaved caspase-3 and BAX, and higher levels of the anti-apoptotic protein, Bcl-2 as compared to WT group. We confirmed that isolated WT cortical neurons express the EphA2 receptor and its ligands (ephrin-A1-A3. Furthermore, expression of all four proteins was increased in WT primary cortical neurons following 24 h of glucose deprivation, and in the brains of WT mice following stroke. Glucose deprivation induced less cell death in primary neurons from EphA2(-/- compared with WT mice. In conclusion, our data provide the first evidence that the EphA2 receptor directly contributes to blood-brain barrier damage and neuronal death following ischemic stroke.

QUANTITATIVE CHANGES IN REGIONAL CEREBRAL BLOOD FLOW INDUCED BY COLD, HEAT AND ISCHEMIC PAIN: A CONTINUOUS ARTERIAL SPIN LABELING STUDY

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Frölich, Michael A.; Deshpande, Hrishikesh; Ness, Timothy; Deutsch, Georg

2012-01-01

Background The development of arterial spin labeling methods, has allowed measuring regional cerebral blood flow (rCBF) quantitatively and to show the pattern of cerebral activity associated with any state such as a sustained pain state or changes due to a neurotropic drug. Methods We studied the differential effects of three pain conditions in ten healthy subjects on a 3T scanner during resting baseline, heat, cold and ischemic pain using continuous arterial spin labeling. Results Cold pain showed the greatest absolute rCBF increases in left anterior cingulate cortex, left amygdala, left angular gyrus, and Brodmann Area 6, and a significant rCBF decrease in the cerebellum. Changes in rCBF were characteristic of the type of pain condition: cold and heat pain showed increases, while the ischemic condition showed a reduction in mean absolute gray matter flow compared to rest. An association of subjects’ pain tolerance and cerebral blood flow was noted. Conclusions The observation that quantitative rCBF changes are characteristic of the pain task employed and that there is a consistent rCBF change in Brodman area 6, an area responsible for the integration of a motor response to pain, should provide extremely useful information in the quest to develop an imaging biomarker of pain. Conceivably, response in BA6 may serve as an objective measure of analgesic efficacy. PMID:22913924

Quantitative changes in regional cerebral blood flow induced by cold, heat and ischemic pain: a continuous arterial spin labeling study.

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Frölich, Michael A; Deshpande, Hrishikesh; Ness, Timothy; Deutsch, Georg

2012-10-01

The development of arterial spin labeling methods has allowed measuring regional cerebral blood flow (rCBF) quantitatively and to show the pattern of cerebral activity associated with any state such as a sustained pain state or changes due to a neurotropic drug. The authors studied the differential effects of three pain conditions in 10 healthy subjects on a 3 Tesla scanner during resting baseline, heat, cold, and ischemic pain using continuous arterial spin labeling. Cold pain showed the greatest absolute rCBF increases in left anterior cingulate cortex, left amygdala, left angular gyrus, and Brodmann area 6, and a significant rCBF decrease in the cerebellum. Changes in rCBF were characteristic of the type of pain condition: cold and heat pain showed increases, whereas the ischemic condition showed a reduction in mean absolute gray matter flow compared with rest. An association of subjects' pain tolerance and cerebral blood flow was noted. The observation that quantitative rCBF changes are characteristic of the pain task used and that there is a consistent rCBF change in Brodman area 6, an area responsible for the integration of a motor response to pain, should provide extremely useful information in the quest to develop an imaging biomarker of pain. Conceivably, response in BA6 may serve as an objective measure of analgesic efficacy.

Insulin-like growth factor -1 (IGF-1) derived neuropeptides, a novel strategy for the development of pharmaceuticals for managing ischemic brain injury.

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Guan, Jian

2011-08-01

Insulin-Like Growth Factor-1 (IGF-1) is neuroprotective and improves long-term function after brain injury. However, its clinical application to neurological disorders is limited by its large molecular size, poor central uptake, and mitogenic potential. Glycine-proline-glutamate (GPE) is naturally cleaved from the IGF-1 N-terminal and is also neuroprotective after ischemic injury, thus providing a potential novel strategy of drug discovery for management of neurological disorders. GPE is not enzymatically stable, thus intravenous infusion of GPE becomes necessary for stable and potent neuroprotection. The broad effective dose range and treatment window of 3-7 h after the lesion suggest its potential for treating acute brain injuries. The neuroprotective action of GPE is not age selective, is not dependent on cerebral reperfusion, plasma glucose concentrations, and core body temperature. G-2mPE, a GPE analogue designed to be more resistant to enzymatic activity, has a prolonged plasma half-life and is more potent in neuroprotection. Neuroprotection by GPE and its analogue may be involved in modulation of inflammation, promotion of astrocytosis, inhibition of apoptosis, and in vascular remodeling. Small neuropeptides have advantages over growth factors in the treatment of brain injury, and modified neuropeptides, designed to overcome the limitations of their endogenous counterparts, represent a novel strategy of pharmaceutical discovery for neurological disorders. © 2010 Blackwell Publishing Ltd.

The ischemic perinatal brain damage

International Nuclear Information System (INIS)

Crisi, G.; Mauri, C.; Canossi, G.; Della Giustina, E.

1986-01-01

The term ''hypoxic-ischemic encephalopathy'' covers a large part of neonatal neuropathology including the various forms of intracerebral haemorrhage. In the present work the term is confined to ischemic brain edema and actual infarction, be it diffuse or focal. Eighteen newborns with CT evidence of ischemic brain lesions and infarctual necrosis were selected. Emphasis is placed on current data on neuropathology of ischemic brain edema and its CT appearance. Particular entities such as periventricular leukomalacia and multicystic encephalopathy are discussed. Relationship between CT and temporal profile of cerebral damage is emphasized in order to predict the structural sequelae and the longterm prognosis

The pro-resolving lipid mediator Maresin 1 protects against cerebral ischemia/reperfusion injury by attenuating the pro-inflammatory response

International Nuclear Information System (INIS)

Xian, Wenjing; Wu, Yan; Xiong, Wei; Li, Longyan; Li, Tong; Pan, Shangwen; Song, Limin; Hu, Lisha; Pei, Lei; Yao, Shanglong

2016-01-01

Inflammation plays a crucial role in acute ischemic stroke pathogenesis. Macrophage-derived Maresin 1 (MaR1) is a newly uncovered mediator with potent anti-inflammatory abilities. Here, we investigated the effect of MaR1 on acute inflammation and neuroprotection in a mouse brain ischemia reperfusion (I/R) model. Male C57 mice were subjected to 1-h middle cerebral artery occlusion (MCAO) and reperfusion. By the methods of 2,3,5-triphenyltetrazolium chloride, haematoxylin and eosin or Fluoro-Jade B staining, neurological deficits scoring, ELISA detection, immunofluorescence assay and western blot analysis, we found that intracerebroventricular injection of MaR1 significantly reduced the infarct volume and neurological defects, essentially protected the brain tissue and neurons from injury, alleviated pro-inflammatory reactions and NF-κB p65 activation and nuclear translocation. Taken together, our results suggest that MaR1 significantly protects against I/R injury probably by inhibiting pro-inflammatory reactions. - Highlights: • MaR1 significantly protects against ischemia reperfusion injury. • MaR1 inhibits pro-inflammatory cytokines and chemokines and reducing glial activation and neutrophil infiltration. • These effects at least partially occurred via suppression of the NF-κB p65 signalling pathway.

The pro-resolving lipid mediator Maresin 1 protects against cerebral ischemia/reperfusion injury by attenuating the pro-inflammatory response

Energy Technology Data Exchange (ETDEWEB)

Xian, Wenjing [Department of Anesthesiology, Institute of Anesthesiology and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Wu, Yan [Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Xiong, Wei [Department of Anesthesiology, Institute of Anesthesiology and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Li, Longyan [Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Li, Tong [Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Pan, Shangwen [Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Song, Limin [Department of Anesthesiology, Institute of Anesthesiology and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Hu, Lisha [Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Pei, Lei [Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Yao, Shanglong, E-mail: ysltian@163.com [Department of Anesthesiology, Institute of Anesthesiology and Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); and others

2016-03-25

Inflammation plays a crucial role in acute ischemic stroke pathogenesis. Macrophage-derived Maresin 1 (MaR1) is a newly uncovered mediator with potent anti-inflammatory abilities. Here, we investigated the effect of MaR1 on acute inflammation and neuroprotection in a mouse brain ischemia reperfusion (I/R) model. Male C57 mice were subjected to 1-h middle cerebral artery occlusion (MCAO) and reperfusion. By the methods of 2,3,5-triphenyltetrazolium chloride, haematoxylin and eosin or Fluoro-Jade B staining, neurological deficits scoring, ELISA detection, immunofluorescence assay and western blot analysis, we found that intracerebroventricular injection of MaR1 significantly reduced the infarct volume and neurological defects, essentially protected the brain tissue and neurons from injury, alleviated pro-inflammatory reactions and NF-κB p65 activation and nuclear translocation. Taken together, our results suggest that MaR1 significantly protects against I/R injury probably by inhibiting pro-inflammatory reactions. - Highlights: • MaR1 significantly protects against ischemia reperfusion injury. • MaR1 inhibits pro-inflammatory cytokines and chemokines and reducing glial activation and neutrophil infiltration. • These effects at least partially occurred via suppression of the NF-κB p65 signalling pathway.

Electroacupuncture ameliorates post-stroke learning and memory through minimizing ultrastructural brain damage and inhibiting the expression of MMP-2 and MMP-9 in cerebral ischemia-reperfusion injured rats.

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Lin, Ruhui; Yu, Kunqiang; Li, Xiaojie; Tao, Jing; Lin, Yukun; Zhao, Congkuai; Li, Chunyan; Chen, Li-Dian

2016-07-01

The aim of the present study was to investigate the potential neuroprotective effects of electroacupuncture (EA) in the treatment of cerebral ischemia/reperfusion (I/R) injury, and to elucidate the association between this neuroprotective effect and brain ultrastructure and expression of matrix metalloproteinase (MMP)‑2 and 9. Rats underwent focal cerebral I/R injury by arterial ligation and received in vivo therapeutic EA at the Baihui (DU20) and Shenting (DU24) acupoints. The therapeutic efficacy was then evaluated following the surgery. The results of the current study demonstrated that EA treatment significantly ameliorated neurological deficits and reduced cerebral infarct volume compared with I/R injured rats. Furthermore, EA improved the learning and memory ability of rats following I/R injury, inhibited blood brain barrier breakdown and reduced neuronal damage in the ischemic penumbra. Furthermore, EA attenuated ultrastructural changes in the brain tissue following ischemia and inhibited MMP‑2/MMP‑9 expression in cerebral I/R injured rats. The results suggest that EA ameliorates anatomical deterioration, and learning and memory deficits in rats with cerebral I/R injury.

Electroacupuncture Ameliorates Learning and Memory via Activation of the CREB Signaling Pathway in the Hippocampus to Attenuate Apoptosis after Cerebral Hypoperfusion

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Han, Xiaohua; Zhao, Xiuxiu; Lu, Min; Liu, Fang; Guo, Feng; Zhang, Jinghui; Huang, Xiaolin

2013-01-01

Studies have shown that electroacupuncture (EA) ameliorates learning and memory after ischemic injury. However, there have been few studies elucidating the mechanisms of EA on learning and memory in cerebral hypoperfusion. In this study, we explored the cAMP response element-binding protein (CREB) signaling pathway-mediated antiapoptotic action involved in EA-induced improvement of learning and memory. EA at GV20 and GV14 acupoints was applied in cerebral hypoperfusion rats. A Morris water ma...

Isoflurane anesthesia initiated at the onset of reperfusion attenuates oxidative and hypoxic-ischemic brain injury.

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Sergey A Sosunov

Full Text Available This study demonstrates that in mice subjected to hypoxia-ischemia (HI brain injury isoflurane anesthesia initiated upon reperfusion limits a release of mitochondrial oxidative radicals by inhibiting a recovery of complex-I dependent mitochondrial respiration. This significantly attenuates an oxidative stress and reduces the extent of HI brain injury. Neonatal mice were subjected to HI, and at the initiation of reperfusion were exposed to isoflurane with or without mechanical ventilation. At the end of HI and isoflurane exposure cerebral mitochondrial respiration, H2O2 emission rates were measured followed by an assessment of cerebral oxidative damage and infarct volumes. At 8 weeks after HI navigational memory and brain atrophy were assessed. In vitro, direct effect of isoflurane on mitochondrial H2O2 emission was compared to that of complex-I inhibitor, rotenone. Compared to controls, 15 minutes of isoflurane anesthesia inhibited recovery of the compex I-dependent mitochondrial respiration and decreased H2O2 production in mitochondria supported with succinate. This was associated with reduced oxidative brain injury, superior navigational memory and decreased cerebral atrophy compared to the vehicle-treated HI-mice. Extended isoflurane anesthesia was associated with sluggish recovery of cerebral blood flow (CBF and the neuroprotection was lost. However, when isoflurane anesthesia was supported with mechanical ventilation the CBF recovery improved, the event associated with further reduction of infarct volume compared to HI-mice exposed to isoflurane without respiratory support. Thus, in neonatal mice brief isoflurane anesthesia initiated at the onset of reperfusion limits mitochondrial release of oxidative radicals and attenuates an oxidative stress. This novel mechanism contributes to neuroprotective action of isoflurane. The use of mechanical ventilation during isoflurane anesthesia counterbalances negative effect of isoflurane anesthesia on

An experimental study on cerebral ischemic penumbra imaging with 99Tcm-HL91

International Nuclear Information System (INIS)

Zhu Cansheng; Jiang Ningyi

2002-01-01

Objective: To investigate the biodistribution of 99 Tc m -4,9-diaza-3,3,10,10-tetramethyl dodecan-2,11-dione dioxime (HL91) in rat model of middle cerebral artery occlusion (MCAO). Methods: Thirty-one MCAO rats were established. Fourteen rats were used to study the biodistribution of 99 Tc m -HL91 and 15 rats were used to study the distribution of 99 Tc m -HL91 in the brain of MCAO model rats. Autoradiographic study of brain was also done in 16 MCAO model rats. Results: The liver and kidney retention were higher than that in other tissues. At 1 h after injection, small intestine retention was also high. But radioactivity in normal brain was low. Retention in target site was higher than that in non-target site. Difference between subgroups of operation and that of pseudo operation was significant (P 99 Tc m -HL91 at the target-ischemic area was shown in the autoradiograph. By using computer-enhanced image analysis, difference between target site and non-target site in the same autoradiograph and the differences between operation subgroups and that of pseudo-subgroups were all significant via Dunnett t-test and One-Way ANOVA. Conclusions: 99 Tc m -HL91 can be avidly taken up by ischemic penumbra and target/non-target ratio is high. 99 Tc m -HL91 is a potential agent for hypoxic tissue imaging, and 99 Tc m -HL91 SPECT is a promising modality in detecting the ischemic penumbra

Ischemic conditioning-induced endogenous brain protection: Applications pre-, per- or post-stroke.

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Wang, Yuechun; Reis, Cesar; Applegate, Richard; Stier, Gary; Martin, Robert; Zhang, John H

2015-10-01

In the area of brain injury and neurodegenerative diseases, a plethora of experimental and clinical evidence strongly indicates the promise of therapeutically exploiting the endogenous adaptive system at various levels like triggers, mediators and the end-effectors to stimulate and mobilize intrinsic protective capacities against brain injuries. It is believed that ischemic pre-conditioning and post-conditioning are actually the strongest known interventions to stimulate the innate neuroprotective mechanism to prevent or reverse neurodegenerative diseases including stroke and traumatic brain injury. Recently, studies showed the effectiveness of ischemic per-conditioning in some organs. Therefore the term ischemic conditioning, including all interventions applied pre-, per- and post-ischemia, which spans therapeutic windows in 3 time periods, has recently been broadly accepted by scientific communities. In addition, it is extensively acknowledged that ischemia-mediated protection not only affects the neurons but also all the components of the neurovascular network (consisting of neurons, glial cells, vascular endothelial cells, pericytes, smooth muscle cells, and venule/veins). The concept of cerebroprotection has been widely used in place of neuroprotection. Intensive studies on the cellular signaling pathways involved in ischemic conditioning have improved the mechanistic understanding of tolerance to cerebral ischemia. This has added impetus to exploration for potential pharmacologic mimetics, which could possibly induce and maximize inherent protective capacities. However, most of these studies were performed in rodents, and the efficacy of these mimetics remains to be evaluated in human patients. Several classical signaling pathways involving apoptosis, inflammation, or oxidation have been elaborated in the past decades. Newly characterized mechanisms are emerging with the advances in biotechnology and conceptual renewal. In this review we are going to focus on

Niosomes of ascorbic acid and α-tocopherol in the cerebral ischemia-reperfusion model in male rats.

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Varshosaz, Jaleh; Taymouri, Somayeh; Pardakhty, Abbas; Asadi-Shekaari, Majid; Babaee, Abodolreza

2014-01-01

The objective of the present study was to prepare a stable iv injectable formulation of ascorbic acid and α-tocopherol in preventing the cerebral ischemia. Different niosomal formulations were prepared by Span and Tween mixed with cholesterol. The physicochemical characteristics of niosomal formulations were evaluated in vitro. For in vivo evaluation, the rats were made ischemic by middle cerebral artery occlusion model for 30 min and the selected formulation was used for determining its neuroprotective effect against cerebral ischemia. Neuronal damage was evaluated by optical microscopy and transmission electron microscopy. The encapsulation efficiency of ascorbic acid was increased to more than 84% by remote loading method. The cholesterol content of the niosomes, the hydrophilicity potential of the encapsulated compounds, and the preparation method of niosomes were the main factors affecting the mean volume diameter of the prepared vesicles. High physical stability of the niosomes prepared from Span 40 and Span 60 was demonstrated due to negligible size change of vesicles during 6 months storage at 4-8(°)C. In vivo studies showed that ST60/Chol 35 : 35 : 30 niosomes had more neuroprotective effects against cerebral ischemic injuries in male rats than free ascorbic acid.

Therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemia/reperfusion injury in rats.

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Guo, Chao; Zhu, Yanrong; Weng, Yan; Wang, Shiquan; Guan, Yue; Wei, Guo; Yin, Ying; Xi, Miaomaio; Wen, Aidong

2014-01-01

Breviscapine injection is a Chinese herbal medicine standardized product extracted from Erigeron breviscapus (Vant.) Hand.-Mazz. It has been widely used for treating cardiovascular and cerebrovascular diseases. However, the therapeutic time window and the action mechanism of breviscapine are still unclear. The present study was designed to investigate the therapeutic time window and underlying therapeutic mechanism of breviscapine injection against cerebral ischemic/reperfusion injury. Sprague-Dawley rats were subjected to middle cerebral artery occlusion for 2h followed by 24h of reperfusion. Experiment part 1 was used to investigate the therapeutic time window of breviscapine. Rats were injected intravenously with 50mg/kg breviscapine at different time-points of reperfusion. After 24h of reperfusion, neurologic score, infarct volume, brain water content and serum level of neuron specific enolase (NSE) were measured in a masked fashion. Part 2 was used to explore the therapeutic mechanism of breviscapine. 4-Hydroxy-2-nonenal (4-HNE), 8-hydroxyl-2'- deoxyguanosine (8-OHdG) and the antioxidant capacity of ischemia cortex were measured by ELISA and ferric-reducing antioxidant power (FRAP) assay, respectively. Immunofluorescence and western blot analysis were used to analyze the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Part 1: breviscapine injection significantly ameliorated neurologic deficit, reduced infarct volume and water content, and suppressed the levels of NSE in a time-dependent manner. Part 2: breviscapine inhibited the increased levels of 4-HNE and 8-OHdG, and enhanced the antioxidant capacity of cortex tissue. Moreover, breviscapine obviously raised the expression of Nrf2 and HO-1 proteins after 24h of reperfusion. The therapeutic time window of breviscapine injection for cerebral ischemia/reperfusion injury seemed to be within 5h after reperfusion. By up-regulating the expression of Nrf2/HO-1 pathway

Cardioprotection against experimental myocardial ischemic injury using cornin

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Y. Xu

2016-01-01

Full Text Available Phosphorylated-cyclic adenosine monophosphate response element-binding protein (Phospho-CREB has an important role in the pathogenesis of myocardial ischemia. We isolated the iridoid glycoside cornin from the fruit of Verbena officinalis L, investigated its effects against myocardial ischemia and reperfusion (I/R injury in vivo, and elucidated its potential mechanism in vitro. Effects of cornin on cell viability, as well as expression of phospho-CREB and phospho-Akt in hypoxic H9c2 cells in vitro, and myocardial I/R injury in vivo, were investigated. Cornin attenuated hypoxia-induced cytotoxicity significantly in H9c2 cells in a concentration-dependent manner. Treatment of H9c2 cells with cornin (10 µM blocked the reduction of expression of phospho-CREB and phospho-Akt in a hypoxic condition. Treatment of rats with cornin (30 mg/kg, iv protected them from myocardial I/R injury as indicated by a decrease in infarct volume, improvement in hemodynamics, and reduction of severity of myocardial damage. Cornin treatment also attenuated the reduction of expression of phospho-CREB and phospho-Akt in ischemic myocardial tissue. These data suggest that cornin exerts protective effects due to an increase in expression of phospho-CREB and phospho-Akt.

Mechanical injury induces brain endothelial-derived microvesicle release: Implications for cerebral vascular injury during traumatic brain injury

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Allison M. Andrews

2016-02-01

Full Text Available It is well established that the endothelium responds to mechanical forces induced by changes in shear stress and mechanotransduction. However, our understanding of vascular remodeling following traumatic brain injury (TBI remains incomplete. Recently published studies have revealed that lung and umbilical endothelial cells produce extracellular microvesicles (eMVs, such as microparticles, in response to changes in mechanical forces (blood flow and mechanical injury. Yet, to date, no studies have shown whether brain endothelial cells produce eMVs following TBI. The brain endothelium is highly specialized and forms the blood-brain barrier (BBB, which regulates diffusion and transport of solutes into the brain. This specialization is largely due to the presence of tight junction proteins (TJPs between neighboring endothelial cells. Following TBI, a breakdown in tight junction complexes at the BBB leads to increased permeability, which greatly contributes to the secondary phase of injury. We have therefore tested the hypothesis that brain endothelium responds to mechanical injury, by producing eMVs that contain brain endothelial proteins, specifically TJPs. In our study, primary human adult brain microvascular endothelial cells (BMVEC were subjected to rapid mechanical injury to simulate the abrupt endothelial disruption that can occur in the primary injury phase of TBI. eMVs were isolated from the media following injury at 2, 6, 24 and 48 hrs. Western blot analysis of eMVs demonstrated a time-dependent increase in TJP occludin, PECAM-1 and ICAM-1 following mechanical injury. In addition, activation of ARF6, a small GTPase linked to extracellular vesicle production, was increased after injury. To confirm these results in vivo, mice were subjected to sham surgery or TBI and blood plasma was collected 24 hrs post-injury. Isolation and analysis of eMVs from blood plasma using cryo-EM and flow cytometry revealed elevated levels of vesicles containing

Mechanical Injury Induces Brain Endothelial-Derived Microvesicle Release: Implications for Cerebral Vascular Injury during Traumatic Brain Injury.

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Andrews, Allison M; Lutton, Evan M; Merkel, Steven F; Razmpour, Roshanak; Ramirez, Servio H

2016-01-01

It is well established that the endothelium responds to mechanical forces induced by changes in shear stress and strain. However, our understanding of vascular remodeling following traumatic brain injury (TBI) remains incomplete. Recently published studies have revealed that lung and umbilical endothelial cells produce extracellular microvesicles (eMVs), such as microparticles, in response to changes in mechanical forces (blood flow and mechanical injury). Yet, to date, no studies have shown whether brain endothelial cells produce eMVs following TBI. The brain endothelium is highly specialized and forms the blood-brain barrier (BBB), which regulates diffusion and transport of solutes into the brain. This specialization is largely due to the presence of tight junction proteins (TJPs) between neighboring endothelial cells. Following TBI, a breakdown in tight junction complexes at the BBB leads to increased permeability, which greatly contributes to the secondary phase of injury. We have therefore tested the hypothesis that brain endothelium responds to mechanical injury, by producing eMVs that contain brain endothelial proteins, specifically TJPs. In our study, primary human adult brain microvascular endothelial cells (BMVEC) were subjected to rapid mechanical injury to simulate the abrupt endothelial disruption that can occur in the primary injury phase of TBI. eMVs were isolated from the media following injury at 2, 6, 24, and 48 h. Western blot analysis of eMVs demonstrated a time-dependent increase in TJP occludin, PECAM-1 and ICAM-1 following mechanical injury. In addition, activation of ARF6, a small GTPase linked to extracellular vesicle production, was increased after injury. To confirm these results in vivo, mice were subjected to sham surgery or TBI and blood plasma was collected 24 h post-injury. Isolation and analysis of eMVs from blood plasma using cryo-EM and flow cytometry revealed elevated levels of vesicles containing occludin following brain trauma

Distribution of ischemic infarction and stenosis of intra- and extracranial arteries in young Chinese patients with ischemic stroke.

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Ojha, Rajeev; Huang, Dongya; An, Hedi; Liu, Rong; Du, Cui; Shen, Nan; Tu, Zhilan; Li, Ying

2015-11-23

The distribution of cerebral ischemic infarction and stenosis in ischemic stroke may vary with age-group, race and gender. This study was conducted to understand the risk factors and characteristics of cerebral infarction and stenosis of vessels in young Chinese patients with ischemic stroke. This was a retrospective study, from January 2007 to July 2012, of 123 patients ≤50 years diagnosed with acute ischemic stroke. Patient characteristics were compared according to sex (98 males and 25 females) and age group (51 patients were ≤45 years and 72 patients were 46-50 years). Characteristics of acute ischemic infarction were studied by diffusion weighted imaging. Stenosis of intra- and extracranial arteries was diagnosed by duplex sonography, head magnetic resonance angiography (MRA) or cervical MRA. Common risk factors were hypertension (72.4 %), dyslipidemia (55.3 %), smoking (54.4 %) and diabetes (33.3 %). Lacunar Infarction was most common in our patients (41.5 %). Partial anterior circulation infarction was predominant in females (52.0 vs 32.7 %; P = 0.073) and posterior circulation infarction in males (19.8 vs 4 %; P = 0.073). Multiple brain infarctions were found in 38 patients (30.9 %). Small artery atherosclerosis was found in 54 patients (43.9 %), with higher prevalence in patients of the 46-50 years age-group. Intracranial stenosis was more common than extracranial stenosis, and middle cerebral artery stenosis was most prevalent (27.3 %). Stenosis in the anterior circulation was more frequent than in the posterior circulation (P young patients, hypertension, smoking, dyslipidemia and diabetes were common risk factors. Intracranial stenosis was most common. The middle cerebral artery was highly vulnerable.

Abnormalities of Microcirculation and Intracranial and Cerebral Perfusion Pressures in Severe Brain Injury

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Yu. A. Churlyaev

2008-01-01

Full Text Available Objective: to evaluate the states of microcirculation, cerebral perfusion intracranial pressures in patients with isolated severe brain injury (SBI and to determine their possible relationships. Subjects and methods. 148 studies were performed in 16 victims with SBI. According to the outcome of brain traumatic disease, the patients were divided into two groups: 1 those who had a good outcome (n=8 and 2 those who had a fatal outcome (n=8. Microcirculation was examined by skin laser Doppler flowmetry using a LAKK-01 capillary blood flow laser analyzer (LAZMA Research-and-Production Association, Russian Federation. All the victims underwent surgical interventions to remove epi-, subdural, and intracerebral hematomas. A Codman subdural/intraparenchymatous intracranial pressure (ICD sensor (Johnson & Johnson, United Kingdom was intraoperatively inserted in the victims. Cerebral perfusion pressure (CPP was calculated using the generally accepted formula: CPP = MBP (mean blood pressure — ICD. ICD, CPP, and microcirculation were studied on postoperative days 1, 3, 5, and 7. Their values were recorded simultaneously. Ninety and 58 studies were conducted in the group of patients with good and fatal outcomes, respectively. Results. No correlation between the changes in MBP, ICD, and microcirculatory parameters suggested that the value of ICD was determined by the nature of brain damage and it was the leading and determining indicator in the diagnosis and treatment of secondary cerebral lesions. The amplitude of low-frequency fluctuations directly correlated with ICD, which indicated that they might be used to evaluate cerebral perfusion and impaired cerebral circulation indirectly in victims with severe brain injury. Conclusion. The laser Doppler flowmetric technique makes it possible not only to qualitatively, but also quantitatively determine changes in the tissue blood flow system in severe brain injury. With this technique, both the local and central

Diffusion-weighted MR imaging in animal modil with acute ischemic brain infarction : evaluation of reversible brain injury

International Nuclear Information System (INIS)

Byun, Woo Mok; Chang, Han Won; Cho, Inn Ho; Hah, Jung Sang; Sung, Eon Gi

2001-01-01

To determine whether the analysis of abnormally high signal intensities in ischemic tissue, as revealed by diffusion-weighted MR imaging (DWI) can be used to evaluate reversible brain lesions in a cat model of acute ischemia. Ten cats were divided into two groups of five (Group I and Group II), and in all animals the middle cerebral artery was temporarily occluded. Group I underwent T2-DWI 30 minutes after occlusion, and Group II 120 minutes after occlusion. In both groups, DWI was performed one hour and 24 hours after reperfusion (at one hour, non-T2-weighted; at 24 hours, T2-weighted). Both occlusion and reperfusion were monitored by 99m TC-ECD brain perfusion SPECT. All animals were sacrificed 24 hours later and their brain tissue was stained with TTC. Signal intensity ratios (SIR, signifying average signal intensity within the region of interest divided by that in the contralateral, nonischemic, homologous region) of the two groups, as seen on DWI were compared. The percentage of hemispheric lesions occurring in the two groups was also compared. SIR after occlusion of the middle cerebral artery was 1.29 in Group I and 1.59 in Group II. Twenty-four hours after reperfusion, SIR in Group I was higher than in Group II (p<0.01). After occlusion and reperfusion, the percentage of hemispheric lesions in Group I was less than in Group II. For the latter, the percentage of these lesions revealed by TTC staining and T2-weighted imaging was 48% and 59%, respectively, findings distinctly different from those for Group I. In addition, in group I, infarction was revealed by neither TTC staining nor T2-weighted imaging (p<0.01). The use of DWI to evaluate signal intensity ratios can help determine whether or not brain injury after temporary cerebral ischemia is reversible

Numerous Fusiform and Saccular Cerebral Aneurysms in Central Nervous System Lupus Presenting with Ischemic Stroke.

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Majidi, Shahram; Leon Guerrero, Christopher R; Gandhy, Shreya; Burger, Kathleen M; Sigounas, Dimitri

2017-07-01

Central nervous system (CNS) involvement occurs in up to 50% of patients with systemic lupus erythematosus (SLE). Cerebral aneurysm formation is a rare complication of CNS lupus. The majority of these patients present with subarachnoid hemorrhage. We report a patient with an active SLE flare who presented with a recurrent ischemic stroke and was found to have numerous unruptured fusiform and saccular aneurysms in multiple vascular territories. He was treated with high-dose steroid and rituximab along with aspirin and blood pressure control for stroke prevention. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

Post Traumatic Cerebral Oedema in Severe Head Injury is Related to Intracranial Pressure and Cerebral Perfusion Pressure but not to Cerebral Compliance

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U Nujaimin

2009-07-01

Full Text Available This was a prospective cohort study, carried out in the Neuro Intensive Care Unit, Department of Neurosciences, Hospital Universiti Sains Malaysia, Kubang Kerian Kelantan. The study was approved by the local ethics committee and was conducted between November 2005 and September 2007 with a total of 30 patients included in the study. In our study, univariate analysis showed a statistically significant relationship between mean intracranial pressure (ICP as well as cerebral perfusion pressure (CPP with both states of basal cistern and the degree of diffuse injury and oedema based on the Marshall classification system. The ICP was higher while CPP and compliance were lower whenever the basal cisterns were effaced in cases of cerebral oedema with Marshall III and IV. In comparison, the study revealed lower ICP, higher mean CPP and better mean cerebral compliance if the basal cisterns were opened or the post operative CT brain scan showed Marshall I and II. These findings suggested the surgical evacuation of clots to reduce the mass volume and restoration of brain anatomy may reduce vascular engorgement and cerebral oedema, therefore preventing intracranial hypertension, and improving cerebral perfusion pressure and cerebral compliance. Nevertheless the study did not find any significant relationship between midline shifts and mean ICP, CPP or cerebral compliance even though lower ICP, higher CPP and compliance were frequently observed when the midline shift was less than 0.5 cm. As the majority of our patients had multiple and diffuse brain injuries, the absence of midline shift did not necessarily mean lower ICP as the pathology was bilateral and even when after excluding the multiple lesions, the result remained insignificant. We assumed that the CT brain scan obtained after evacuation of the mass lesion to assess the state basal cistern and classify the diffuse oedema may prognosticate the intracranial pressure and cerebral perfusion pressure

The experimental study of CT-guided hepatocyte growth factor gene therapy for cerebral ischemic diseases

International Nuclear Information System (INIS)

Zhang Xiaobo; Jin Zhengyu; Li Mingli; Wang Renzhi; Li Guilin; Kong Yanguo; Wang Jianming; Gao Shan; Guan Hongzhi; Wang Detian; Luo Yufeng

2006-01-01

Objectives: To investigate the feasibility of CT guided hepatocyte growth factor (HGF) gene therapy for cerebral ischemic diseases. Methods: Human HGF cDNA was ligated to pIRES 2 -EGFP vector. The recombinant plasmid was transfected into the penumbra tissue with liposome, guided by CT perfusion images. After seven days of transfer with recombinant plasmid, the cut sections of rat brain tissues of the treated and control groups were analyzed including immunohistochemistry, vessel count, cerebral blood flow and infarct volume etc. in order to investigate HGF gene expression and biological effect. Results: Enzymatic digestion and electrophoresis confirmed that HGF fragments had been correctly cloned into the space between the BamH I and Sal I sites of pIRES 2 -EGFP. After 7 days of HGF gene transfection, expression of HGF in transfected neurocytes of treated group was observed with immunohistochemistry. The number of vessels in penumbra tissues transfected with HGF vectors and the CBF measured by perfusion CT all were significantly increased than those of the controls (P 2 -EGFP-HGF complexes can transfect the penumbra tissues and definitely express HGF protein. The HGF gene products can stimulate angiogenesis, promote collateral circulation formation and reduce infarct volume in vivo and therefore is beneficial to the treatment of cerebral ischemia. (authors)

Interferon-β Modulates Inflammatory Response in Cerebral Ischemia.

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Kuo, Ping-Chang; Scofield, Barbara A; Yu, I-Chen; Chang, Fen-Lei; Ganea, Doina; Yen, Jui-Hung

2016-01-08

Stroke is a leading cause of death in the world. In >80% of strokes, the initial acute phase of ischemic injury is due to the occlusion of a blood vessel resulting in severe focal hypoperfusion, excitotoxicity, and oxidative damage. Interferon-β (IFNβ), a cytokine with immunomodulatory properties, was approved by the US Food and Drug Administration for the treatment of relapsing-remitting multiple sclerosis for more than a decade. Its anti-inflammatory properties and well-characterized safety profile suggest that IFNβ has therapeutic potential for the treatment of ischemic stroke. We investigated the therapeutic effect of IFNβ in the mouse model of transient middle cerebral artery occlusion/reperfusion. We found that IFNβ not only reduced infarct size in ischemic brains but also lessened neurological deficits in ischemic stroke animals. Further, multiple molecular mechanisms by which IFNβ modulates ischemic brain inflammation were identified. IFNβ reduced central nervous system infiltration of monocytes/macrophages, neutrophils, CD4(+) T cells, and γδ T cells; inhibited the production of inflammatory mediators; suppressed the expression of adhesion molecules on brain endothelial cells; and repressed microglia activation in the ischemic brain. Our results demonstrate that IFNβ exerts a protective effect against ischemic stroke through its anti-inflammatory properties and suggest that IFNβ is a potential therapeutic agent, targeting the reperfusion damage subsequent to the treatment with tissue plasminogen activator. © 2016 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

Neuronal SIRT1 (Silent Information Regulator 2 Homologue 1) Regulates Glycolysis and Mediates Resveratrol-Induced Ischemic Tolerance.

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Koronowski, Kevin B; Khoury, Nathalie; Saul, Isabel; Loris, Zachary B; Cohan, Charles H; Stradecki-Cohan, Holly M; Dave, Kunjan R; Young, Juan I; Perez-Pinzon, Miguel A

2017-11-01

Resveratrol, at least in part via SIRT1 (silent information regulator 2 homologue 1) activation, protects against cerebral ischemia when administered 2 days before injury. However, it remains unclear if SIRT1 activation must occur, and in which brain cell types, for the induction of neuroprotection. We hypothesized that neuronal SIRT1 is essential for resveratrol-induced ischemic tolerance and sought to characterize the metabolic pathways regulated by neuronal Sirt1 at the cellular level in the brain. We assessed infarct size and functional outcome after transient 60 minute middle cerebral artery occlusion in control and inducible, neuronal-specific SIRT1 knockout mice. Nontargeted primary metabolomics analysis identified putative SIRT1-regulated pathways in brain. Glycolytic function was evaluated in acute brain slices from adult mice and primary neuronal-enriched cultures under ischemic penumbra-like conditions. Resveratrol-induced neuroprotection from stroke was lost in neuronal Sirt1 knockout mice. Metabolomics analysis revealed alterations in glucose metabolism on deletion of neuronal Sirt1 , accompanied by transcriptional changes in glucose metabolism machinery. Furthermore, glycolytic ATP production was impaired in acute brain slices from neuronal Sirt1 knockout mice. Conversely, resveratrol increased glycolytic rate in a SIRT1-dependent manner and under ischemic penumbra-like conditions in vitro. Our data demonstrate that resveratrol requires neuronal SIRT1 to elicit ischemic tolerance and identify a novel role for SIRT1 in the regulation of glycolytic function in brain. Identification of robust neuroprotective mechanisms that underlie ischemia tolerance and the metabolic adaptations mediated by SIRT1 in brain are crucial for the translation of therapies in cerebral ischemia and other neurological disorders. © 2017 American Heart Association, Inc.

Aerobic exercise combined with huwentoxin-I mitigates chronic cerebral ischemia injury

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Hai-feng Mao

2017-01-01

Full Text Available Ca2+ channel blockers have been shown to protect neurons from ischemia, and aerobic exercise has significant protective effects on a variety of chronic diseases. The present study injected huwentoxin-I (HWTX-I, a spider peptide toxin that blocks Ca2+ channels, into the caudal vein of a chronic cerebral ischemia mouse model, once every 2 days, for a total of 15 injections. During this time, a subgroup of mice was subjected to treadmill exercise for 5 weeks. Results showed amelioration of cortical injury and improved neurological function in mice with chronic cerebral ischemia in the HWTX-I + aerobic exercise group. The combined effects of HWTX-I and exercise were superior to HWTX-I or aerobic exercise alone. HWTX-I effectively activated the Notch signal transduction pathway in brain tissue. Aerobic exercise up-regulated synaptophysin mRNA expression. These results demonstrated that aerobic exercise, in combination with HWTX-I, effectively relieved neuronal injury induced by chronic cerebral ischemia via the Notch signaling pathway and promoting synaptic regeneration.

Detection of hypoxic-ischemic brain injury with 3D-enhanced T2* weighted angiography (ESWAN) imaging

Energy Technology Data Exchange (ETDEWEB)

Gang, QiangQiang, E-mail: rousikang@163.com; Zhang, Jianing, E-mail: 1325916060@qq.com; Hao, Peng, E-mail: 1043600590@qq.com; Xu, Yikai, E-mail: yikaivip@163.com

2013-11-01

Objective: To demonstrate the use of 3D-enhanced T2* weighted angiography (ESWAN) imaging for the observation and quantification of the evolution of brain injury induced by a recently developed model of hypoxic-ischemic brain injury (HI/R) in neonatal piglets. Methods: For these experiments, newborn piglets were subjected to HI/R injury, during which ESWAN scanning was performed, followed by H and E staining and immunohistochemistry of AQP-4 expression. Results: In the striatum, values from T2* weighted magnetic resonance imaging (MRI) increased and reached their highest level at 3 days post injury, whereas T2* values increased and peaked at 24 h in the subcortical region. The change in T2* values was concordant with brain edema. Phase values in the subcortical border region were not dependent on time post-injury. Magnitude values were significantly different from the control group, and increased gradually over time in the subcortical border region. Susceptibility-weighted images (SWI) indicated small petechial hemorrhages in the striatum and thalamus, as well as dilated intramedullary veins. Conclusion: SWI images can be used to detect white and gray matter microhemorrhages and dilated intramedullary veins. The T2*, phase, and magnitude map can also reflect the development of brain injury. Our data illustrate that ESWAN imaging can increase the diagnostic sensitivity and specificity of MRI in neonatal hypoxic-ischemic encephalopathy.

Detection of hypoxic-ischemic brain injury with 3D-enhanced T2* weighted angiography (ESWAN) imaging

International Nuclear Information System (INIS)

Gang, QiangQiang; Zhang, Jianing; Hao, Peng; Xu, Yikai

2013-01-01

Objective: To demonstrate the use of 3D-enhanced T2* weighted angiography (ESWAN) imaging for the observation and quantification of the evolution of brain injury induced by a recently developed model of hypoxic-ischemic brain injury (HI/R) in neonatal piglets. Methods: For these experiments, newborn piglets were subjected to HI/R injury, during which ESWAN scanning was performed, followed by H and E staining and immunohistochemistry of AQP-4 expression. Results: In the striatum, values from T2* weighted magnetic resonance imaging (MRI) increased and reached their highest level at 3 days post injury, whereas T2* values increased and peaked at 24 h in the subcortical region. The change in T2* values was concordant with brain edema. Phase values in the subcortical border region were not dependent on time post-injury. Magnitude values were significantly different from the control group, and increased gradually over time in the subcortical border region. Susceptibility-weighted images (SWI) indicated small petechial hemorrhages in the striatum and thalamus, as well as dilated intramedullary veins. Conclusion: SWI images can be used to detect white and gray matter microhemorrhages and dilated intramedullary veins. The T2*, phase, and magnitude map can also reflect the development of brain injury. Our data illustrate that ESWAN imaging can increase the diagnostic sensitivity and specificity of MRI in neonatal hypoxic-ischemic encephalopathy

Carvacrol Exerts Neuroprotective Effects Via Suppression of the Inflammatory Response in Middle Cerebral Artery Occlusion Rats.

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Li, Zhenlan; Hua, Cong; Pan, Xiaoqiang; Fu, Xijia; Wu, Wei

2016-08-01

Increasing evidence demonstrates that inflammation plays an important role in cerebral ischemia. Carvacrol, a monoterpenic phenol, is naturally occurring in various plants belonging to the family Lamiaceae and exerts protective effects in a mice model of focal cerebral ischemia/reperfusion injury by reducing infarct volume and decreasing the expression of cleaved caspase-3. However, the anti-inflammatory mechanisms by which carvacrol protect the brain have yet to be fully elucidated. We investigated the effects of carvacrol on inflammatory reaction and inflammatory mediators in middle cerebral artery occlusion rats. The results of the present study showed that carvacrol inhibited the levels of inflammatory cytokines and myeloperoxidase (MPO) activity, as well as the expression of iNOS and COX-2. It also increased SOD activity and decreased MDA level in ischemic cortical tissues. In addition, carvacrol treatment suppressed the ischemia/reperfusion-induced increase in the protein expression of nuclear NF-kB p65. In conclusion, we have shown that carvacrol inhibits the inflammatory response via inhibition of the NF-kB signaling pathway in a rat model of focal cerebral ischemia. Therefore, carvacrol may be a potential therapeutic agent for the treatment of cerebral ischemia injury.

The preliminary study of CT cerebral perfusion imaging in transient ischemic attacks

International Nuclear Information System (INIS)

Lu Jie; Li Kuncheng; Du Xiangying

2002-01-01

Objective: To probe the application of CT cerebral perfusion imaging on transient ischemic attacks (TIA). Methods: Conventional CT and CT cerebral perfusion imaging were performed on 5 normal adults and 20 patients with clinically diagnosed TIA. After regular CT examination, dynamic scans of 40 seconds were performed on selected slice (usually on the basal ganglia slice), while 40 ml non-ionic contrast material were bolus injected through antecubital vein with. These dynamic images were processed with the 'Perfusion CT' software package on a PC based workstation. Cerebral blood flow (CBF) and time to peak (TP) enhancement were measured within specific regions of the brain on CT perfusion images. Quantitative analysis was performed for these images. Results: A gradient of perfusion between gray matter and white matter was showed on cT perfusion images in normal adults and TIA patients. CBF and TP for normal cortical and white matter were 378.2 ml·min -1 ·L -1 , 7.8 s and 112.5 ml·min -1 ·L -1 , 9.9 s, respectively. In 20 cases with TIA, persisting abnormal perfusion changes corresponding to clinical symptoms were found in 15 cases with prolonged TP. Other 5 cases showed normal results. TP of affected side (11.8 +- 4.4) s compared with that of the contralateral side (9.1 +- 3.1) s was significantly prolonged (t = 5.277, P -1 · -1 ] and contralateral side [(229.1 +- 41.4) ml·min -1 ·L -1 ]. Conclusion: Perfusion CT provides valuable hemodynamic information and shows the extent of perfusion disturbances for patients with TIA

Diagnostic Accuracy of a New Cardiac Electrical Biomarker for Detection of Electrocardiogram Changes Suggestive of Acute Myocardial Ischemic Injury

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Schreck, David M; Fishberg, Robert D

2014-01-01

Objective A new cardiac “electrical” biomarker (CEB) for detection of 12-lead electrocardiogram (ECG) changes indicative of acute myocardial ischemic injury has been identified. Objective was to test CEB diagnostic accuracy. Methods This is a blinded, observational retrospective case-control, noninferiority study. A total of 508 ECGs obtained from archived digital databases were interpreted by cardiologist and emergency physician (EP) blinded reference standards for presence of acute myocardial ischemic injury. CEB was constructed from three ECG cardiac monitoring leads using nonlinear modeling. Comparative active controls included ST voltage changes (J-point, ST area under curve) and a computerized ECG interpretive algorithm (ECGI). Training set of 141 ECGs identified CEB cutoffs by receiver-operating-characteristic (ROC) analysis. Test set of 367 ECGs was analyzed for validation. Poor-quality ECGs were excluded. Sensitivity, specificity, and negative and positive predictive values were calculated with 95% confidence intervals. Adjudication was performed by consensus. Results CEB demonstrated noninferiority to all active controls by hypothesis testing. CEB adjudication demonstrated 85.3–94.4% sensitivity, 92.5–93.0% specificity, 93.8–98.6% negative predictive value, and 74.6–83.5% positive predictive value. CEB was superior against all active controls in EP analysis, and against ST area under curve and ECGI by cardiologist. Conclusion CEB detects acute myocardial ischemic injury with high diagnostic accuracy. CEB is instantly constructed from three ECG leads on the cardiac monitor and displayed instantly allowing immediate cost-effective identification of patients with acute ischemic injury during cardiac rhythm monitoring. PMID:24118724

Agmatine attenuates brain edema through reducing the expression of aquaporin-1 after cerebral ischemia

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Kim, Jae Hwan; Lee, Yong Woo; Park, Kyung Ah; Lee, Won Taek; Lee, Jong Eun

2010-01-01

Brain edema is frequently shown after cerebral ischemia. It is an expansion of brain volume because of increasing water content in brain. It causes to increase mortality after stroke. Agmatine, formed by the decarboxylation of -arginine by arginine decarboxylase, has been shown to be neuroprotective in trauma and ischemia models. The purpose of this study was to investigate the effect of agmatine for brain edema in ischemic brain damage and to evaluate the expression of aquaporins (AQPs). Results showed that agmatine significantly reduced brain swelling volume 22 h after 2 h middle cerebral artery occlusion in mice. Water content in brain tissue was clearly decreased 24 h after ischemic injury by agmatine treatment. Blood–brain barrier (BBB) disruption was diminished with agmatine than without. The expressions of AQPs-1 and -9 were well correlated with brain edema as water channels, were significantly decreased by agmatine treatment. It can thus be suggested that agmatine could attenuate brain edema by limitting BBB disruption and blocking the accumulation of brain water content through lessening the expression of AQP-1 after cerebral ischemia. PMID:20029450

Protective Effect of Extract of Folium Ginkgo on Repeated Cerebral Ischemia-Reperfusion Injury

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

Objective: To study the protective effect of extract of Folium Ginkgo (FGE) on repeated cerebral ischemia-reperfusion injury. Methods: The model in waking mice induced by repeated cerebral ischemia-reperfusion were used in the experiment to observe the effect of FGE on behavior, oxygen free radical metabolism and prostaglandin E2 (PGE2) content by step-through experiment, diving stand and colorimetric method. Results: FGE could obviously improve the learning ability and memory of model animals, and could lower obviously the content of malonyldialdehyde, nitric oxide and PGE2, restore the lowered activity of superoxide dismutase and catalase in cerebral tissue. Conclusion: FGE has highly protective effect against repeated ischemia-reperfusion injury, the mechanism might be related with its action on anti-lipid oxidatin, improve the activity of antioxidase and inhibit the producing of PGE2.

High-Target Versus Low-Target Blood Pressure Management During Cardiopulmonary Bypass to Prevent Cerebral Injury in Cardiac Surgery Patients: A Randomized Controlled Trial.

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Vedel, Anne G; Holmgaard, Frederik; Rasmussen, Lars S; Langkilde, Annika; Paulson, Olaf B; Lange, Theis; Thomsen, Carsten; Olsen, Peter Skov; Ravn, Hanne Berg; Nilsson, Jens C

2018-04-24

Cerebral injury is an important complication after cardiac surgery with the use of cardiopulmonary bypass. The rate of overt stroke after cardiac surgery is 1% to 2%, whereas silent strokes, detected by diffusion-weighted magnetic resonance imaging, are found in up to 50% of patients. It is unclear whether a higher versus a lower blood pressure during cardiopulmonary bypass reduces cerebral infarction in these patients. In a patient- and assessor-blinded randomized trial, we allocated patients to a higher (70-80 mm Hg) or lower (40-50 mm Hg) target for mean arterial pressure by the titration of norepinephrine during cardiopulmonary bypass. Pump flow was fixed at 2.4 L·min -1 ·m -2 . The primary outcome was the total volume of new ischemic cerebral lesions (summed in millimeters cubed), expressed as the difference between diffusion-weighted imaging conducted preoperatively and again postoperatively between days 3 and 6. Secondary outcomes included diffusion-weighted imaging-evaluated total number of new ischemic lesions. Among the 197 enrolled patients, mean (SD) age was 65.0 (10.7) years in the low-target group (n=99) and 69.4 (8.9) years in the high-target group (n=98). Procedural risk scores were comparable between groups. Overall, diffusion-weighted imaging revealed new cerebral lesions in 52.8% of patients in the low-target group versus 55.7% in the high-target group ( P =0.76). The primary outcome of volume of new cerebral lesions was comparable between groups, 25 mm 3 (interquartile range, 0-118 mm 3 ; range, 0-25 261 mm 3 ) in the low-target group versus 29 mm 3 (interquartile range, 0-143 mm 3 ; range, 0-22 116 mm 3 ) in the high-target group (median difference estimate, 0; 95% confidence interval, -25 to 0.028; P =0.99), as was the secondary outcome of number of new lesions (1 [interquartile range, 0-2; range, 0-24] versus 1 [interquartile range, 0-2; range, 0-29] respectively; median difference estimate, 0; 95% confidence interval, 0-0; P =0

Glibenclamide for the treatment of ischemic and hemorrhagic stroke.

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Caffes, Nicholas; Kurland, David B; Gerzanich, Volodymyr; Simard, J Marc

2015-03-04

Ischemic and hemorrhagic strokes are associated with severe functional disability and high mortality. Except for recombinant tissue plasminogen activator, therapies targeting the underlying pathophysiology of central nervous system (CNS) ischemia and hemorrhage are strikingly lacking. Sur1-regulated channels play essential roles in necrotic cell death and cerebral edema following ischemic insults, and in neuroinflammation after hemorrhagic injuries. Inhibiting endothelial, neuronal, astrocytic and oligodendroglial sulfonylurea receptor 1-transient receptor potential melastatin 4 (Sur1-Trpm4) channels and, in some cases, microglial KATP (Sur1-Kir6.2) channels, with glibenclamide is protective in a variety of contexts. Robust preclinical studies have shown that glibenclamide and other sulfonylurea agents reduce infarct volumes, edema and hemorrhagic conversion, and improve outcomes in rodent models of ischemic stroke. Retrospective studies suggest that diabetic patients on sulfonylurea drugs at stroke presentation fare better if they continue on drug. Additional laboratory investigations have implicated Sur1 in the pathophysiology of hemorrhagic CNS insults. In clinically relevant models of subarachnoid hemorrhage, glibenclamide reduces adverse neuroinflammatory and behavioral outcomes. Here, we provide an overview of the preclinical studies of glibenclamide therapy for CNS ischemia and hemorrhage, discuss the available data from clinical investigations, and conclude with promising preclinical results that suggest glibenclamide may be an effective therapeutic option for ischemic and hemorrhagic stroke.

Glibenclamide for the Treatment of Ischemic and Hemorrhagic Stroke

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Nicholas Caffes

2015-03-01

Full Text Available Ischemic and hemorrhagic strokes are associated with severe functional disability and high mortality. Except for recombinant tissue plasminogen activator, therapies targeting the underlying pathophysiology of central nervous system (CNS ischemia and hemorrhage are strikingly lacking. Sur1-regulated channels play essential roles in necrotic cell death and cerebral edema following ischemic insults, and in neuroinflammation after hemorrhagic injuries. Inhibiting endothelial, neuronal, astrocytic and oligodendroglial sulfonylurea receptor 1–transient receptor potential melastatin 4 (Sur1–Trpm4 channels and, in some cases, microglial KATP (Sur1–Kir6.2 channels, with glibenclamide is protective in a variety of contexts. Robust preclinical studies have shown that glibenclamide and other sulfonylurea agents reduce infarct volumes, edema and hemorrhagic conversion, and improve outcomes in rodent models of ischemic stroke. Retrospective studies suggest that diabetic patients on sulfonylurea drugs at stroke presentation fare better if they continue on drug. Additional laboratory investigations have implicated Sur1 in the pathophysiology of hemorrhagic CNS insults. In clinically relevant models of subarachnoid hemorrhage, glibenclamide reduces adverse neuroinflammatory and behavioral outcomes. Here, we provide an overview of the preclinical studies of glibenclamide therapy for CNS ischemia and hemorrhage, discuss the available data from clinical investigations, and conclude with promising preclinical results that suggest glibenclamide may be an effective therapeutic option for ischemic and hemorrhagic stroke.

Effect of electroacupuncture on TRPM7 mRNA expression after cerebral ischemia/reperfusion in rats via TrkA pathway.

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Zhao, Li; Shi, Jing; Sun, Ning; Tian, Shunlian; Meng, Xianfang; Liu, Xiaochun; Li, Lingli

2005-01-01

The effect of electroacupuncture (EA) on TRPM7 mRNA expression of focal cerebral ischemia in rats and further the role of EA in the relationship between TRPM7 and trkA pathway was investigated. Thirty SD rats were randomly divided into 5 groups : normal group, ischemia/reperfusion group, EA treated group (ischemic rats with EA treatment), TE infusion group (ischemic rats with EA treatment and TE buffer infusion), AS-ODN group (ischemic rats with EA treatment and antisense trkA oligonucleotide infusion). The stroke animal model was established by the modified method of middle cerebral artery occlusion. Antisense trkA oligonucleotide that blocked NGFs effects was injected into cerebroventricle before EA. The TRPM7 mRNA was detected by RT-PCR method. The results showed that there were low TRPM7 mRNA levels in cortex and hippocampus in normal group. Compared with normal group, TRPM7 mRNA expression was increased significantly in ischemia/reperfusion group (PPM7 mRNA was found in EA treated group in contrast to ischemia/reperfusion group (P<0.05). The expression of TRPM7 mRNA in AS-ODN group was remarkably increased compared with EA treated group and TE infusion group (P<0.05). The results indicated that TRPM7 channels in the ischemic cortex and hippocampus in rats might play a key role in ischemic brain injury. EA could reverse the overexpression of TRPM7 in cerebral ischemia/reperfusion rats. And the inhibitory effect of EA on TRPM7 channels might be through trkA pathway.

Cerebral angiographic findings in thromboangiitis obliterans

International Nuclear Information System (INIS)

No, Young J.; Lee, Eun M.; Kim, Jong S.; Lee, Deok H.

2005-01-01

Transient ischemic attacks (TIAs) or ischemic stroke may complicate thromboangiitis obliterans (TAO). However, there has been debate regarding the mechanism of ischemic stroke in TAO. We report the case of a patient with TAO who developed repeated TIAs. An angiogram showed multiple alternative areas of arterial occlusions in the distal segments of both middle cerebral arteries. Extensive collateral vessels around the occluded segment were also observed, which resembled the ''tree root'' or ''corkscrew'' vessels described in the peripheral arteries in TAO. Our patient illustrates that cerebral manifestations of TAO may occur with vascular changes that are identical with those encountered in the limb arteries in TAO. (orig.)

Salvia miltiorrhiza Bunge (Danshen) extract attenuates permanent cerebral ischemia through inhibiting platelet activation in rats.

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Fei, Yu-Xiang; Wang, Si-Qi; Yang, Li-Jian; Qiu, Yan-Ying; Li, Yi-Ze; Liu, Wen-Yuan; Xi, Tao; Fang, Wei-Rong; Li, Yun-Man

2017-07-31

Danshen is a crude herbal drug isolated from dried roots of Salvia miltiorrhiza Bunge. This plant is widely used in oriental medicine for the treatment of cardiovascular and cerebrovascular diseases. The supercritical CO 2 extract from Danshen (SCED) (57.85%, 5.67% and 4.55% for tanshinone IIA, tanshinone I and cryptotanshinone respectively) was studied in this article, whose potential molecular mechanism remains unclear, especially in anti-thrombosis. The present study was designed to observe the protective effect of SCED on ischemic stroke in rats and to explore the underlying anti-thrombosis mechanism. Following induction of cerebral ischemia in rats by permanent middle cerebral artery occlusion (pMCAO). Neurological defect score, cerebral blood flow, infarct size, and brain edema were measured to evaluate the injury. Arteriovenous shunt thrombosis model and adenosine 5'-diphosphate (ADP) induced acute pulmonary embolism model were conducted to estimate the antithrombotic effect of SCED. In order to investigate the effects of SCED on platelet aggregation, rat platelet-rich-plasma (PRP) were incubated with SCED prior to the addition of the stimuli (ADP or 9, 11-dideoxy-11α, 9α-epoxymethanoprostaglandin F2α (U46619)). Aggregation was monitored in a light transmission aggregometer. Inhibitory effect of SCED on thromboxane A2 (TXA 2 ) release was detected by ELISA kit. Phospholipase C (PLC)/ Protein kinase C (PKC) signaling pathway was analyzed by a Western blot technique. The effect of the SCED was also studied in vivo on bleeding time in mice. SCED improved the neurological defect score, increased cerebral blood flow, reduced infarct size and alleviated brain edema in rats exposed to pMCAO. After administration of SCED, thrombosis formation in arteriovenous shunt was inhibited and recovery time in pulmonary embolism was shortened. The inhibitory effect of SCED on platelet activation was further confirmed by TXB 2 ELISA kit and Western blot analysis of PLC

Post traumatic brain perfusion SPECT analysis using reconstructed ROI maps of radioactive microsphere derived cerebral blood flow and statistical parametric mapping

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Gonzalez-Brito Manuel

2008-02-01

Full Text Available Abstract Background Assessment of cerebral blood flow (CBF by SPECT could be important in the management of patients with severe traumatic brain injury (TBI because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia, or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. Methods The focal effects of moderate traumatic brain injury (TBI on cerebral blood flow (CBF by SPECT cerebral blood perfusion (CBP imaging in an animal model were investigated by parallelized statistical techniques. Regional CBF was measured by radioactive microspheres and by SPECT 2 hours after injury in sham-operated piglets versus those receiving severe TBI by fluid-percussion injury to the left parietal lobe. Qualitative SPECT CBP accuracy was assessed against reference radioactive microsphere regional CBF measurements by map reconstruction, registration and smoothing. Cerebral hypoperfusion in the test group was identified at the voxel level using statistical parametric mapping (SPM. Results A significant area of hypoperfusion (P Conclusion The suitability of SPM for application to the experimental model and ability to provide insight into CBF changes in response to traumatic injury was validated by the SPECT SPM result of a decrease in CBP at the left parietal region injury area of the test group. Further study and correlation of this characteristic lesion with long-term outcomes and auxiliary diagnostic modalities is critical to developing more effective critical care treatment guidelines and automated medical imaging processing techniques.

The synergetic effect of edaravone and borneol in the rat model of ischemic stroke.

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Wu, Hai-Yin; Tang, Ying; Gao, Li-Yan; Sun, Wei-Xiang; Hua, Yao; Yang, Shi-Bao; Zhang, Zheng-Ping; Liao, Gao-Yong; Zhou, Qi-Gang; Luo, Chun-Xia; Zhu, Dong-Ya

2014-10-05

Free radical production contributes to the early ischemic response and the neuroinflammatory response to injury initiates the second wave of cell death following ischemic stroke. Edaravone is a free radical scavenger, and borneol has shown anti-inflammatory effect. We investigated the synergistic effect of these two drugs in the rat model of transient cerebral ischemia. Edaravone scavenged OH, NO and ONOO─ concentration-dependently, and borneol inhibited ischemia/reperfusion-induced tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β) and cyclooxygenase-2 (COX-2) expressions. In the rat model of transient cerebral ischemia and reperfusion, the combination of edaravone and borneol significantly ameliorated ischemic damage with an optimal proportion of 4:1. Emax (% inhibition) of edaravone, borneol and two drugs in combination was 55.7%, 65.8% and 74.3% respectively. ED50 of edaravone and borneol was 7.17 and 0.36 mg/kg respectively. When two drugs in combination, ED50 was 0.484 mg/kg, in which edaravone was 0.387 mg/kg (ineffective dose) and borneol was 0.097 mg/kg (ineffective dose). Combination index (CI)edaravone and borneol. The combination exhibited a therapeutic time window of 6h in ischemia/reperfusion model, and significantly ameliorated damages in permanent ischemia model. Moreover, two drugs in combination promoted long-term effect, including improved elemental vital signs, sensorimotor functions and spatial cognition. Our results suggest that the combination of edaravone and borneol have a synergistic effect for treating ischemic stroke. Copyright © 2014 Elsevier B.V. All rights reserved.

Arctigenin attenuates ischemic stroke via SIRT1-dependent inhibition of NLRP3 inflammasome.

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Zhang, Shimeng; Jiang, Liangjun; Che, Fengyuan; Lu, Yucheng; Xie, Zhongxiang; Wang, Hao

2017-11-04

Arctigenin (ARC), a phenylpropanoid dibenzylbutyrolactone lignan derived from Arctium lappa L, has been reported to protect against cerebral ischemia injury in rats, but the underlying mechanism is unclear. In this study, we investigated whether ARC ameliorated ischemic stroke by inhibiting NLRP3 inflammasome-derived neuroinflammation and whether SIRT1 signaling was involved in this process. ARC (20 mg/kg) or vehicle were intraperitoneally injected to Sprague-Dawley rats for 3 days before middle cerebral artery occlusion (MCAO) surgery performed. The infarct volume, neurological score, brain water content, neuroinflammation, NLRP3 inflammasome activation and SIRT1 protein expression were assessed. Furthermore, we also investigated whether ARC protected against cerebral ischemia via SIRT1-dependent inhibition of NLRP3 inflammasome by administrating EX527, a specific SIRT1 inhibitor, under oxygen-glucose deprivation (OGD) condition. We found that ARC pretreatment decreased infarct volume, neurological score and brain water content. Moreover, ARC treatment effectively inhibited cerebral ischemia induced NLRP3 inflammasome activation and IL-1β, IL-18 secretion both in vivo and in vitro. Futhermore, ARC treatment activated Silent information regulator 1 (SIRT1) singnaling in the brain. Importantly, suppress of SIRT1 reversed the inhibitory effect of ARC on NLRP3 inflammasome activation. Taken together our results demonstrated that ARC may confer protection against ischemic stroke by inhibiting NLRP3 inflammasome activation. The activation of SIRT1 signaling pathway may contribute to the neuroprotection of ARC in MCAO. Copyright © 2017 Elsevier Inc. All rights reserved.

Is higher body temperature beneficial in ischemic stroke patients with normal admission CT angiography of the cerebral arteries?

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Kvistad, Christopher Elnan; Khanevski, Andrej; Nacu, Aliona; Thomassen, Lars; Waje-Andreassen, Ulrike; Naess, Halvor

2014-01-01

Low body temperature is considered beneficial in ischemic stroke due to neuroprotective mechanisms, yet some studies suggest that higher temperatures may improve clot lysis and outcomes in stroke patients treated with tissue plasminogen activator (tPA). The effect of increased body temperature in stroke patients treated with tPA and with normal computed tomography angiography (CTA) on admission is unknown. We hypothesized a beneficial effect of higher body temperature in the absence of visible clots on CTA, possibly due to enhanced lysis of small, peripheral clots. Patients with ischemic stroke admitted to our Stroke Unit between February 2006 and April 2013 were prospectively registered in a database (Bergen NORSTROKE Registry). Ischemic stroke patients treated with tPA with normal CTA of the cerebral arteries were included. Outcomes were assessed by the modified Rankin Scale (mRS) after 1 week. An excellent outcome was defined as mRS=0, and a favorable outcome as mRS=0-1. A total of 172 patients were included, of which 48 (27.9%) had an admission body temperature ≥37.0°C, and 124 (72.1%) had a body temperature temperature ≥37.0°C was independently associated with excellent outcomes (odds ratio [OR]: 2.8; 95% confidence interval [CI]: 1.24-6.46; P=0.014) and favorable outcomes (OR: 2.8; 95% CI: 1.13-4.98; P=0.015) when adjusted for confounders. We found an association between higher admission body temperature and improved outcome in tPA-treated stroke patients with normal admission CTA of the cerebral arteries. This may suggest a beneficial effect of higher body temperature on clot lysis in the absence of visible clots on CTA.

[New developments in spastic unilateral cerebral palsy].

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Chabrier, S; Roubertie, A; Allard, D; Bonhomme, C; Gautheron, V

2010-01-01

Hemiplegic (or spastic unilateral) cerebral palsy accounts for about 30% of all cases of cerebral palsy. With a population prevalence of 0.6 per 1000 live births, it is the most common type of cerebral palsy among term-born children and the second most common type after diplegia among preterm infants. Many types of prenatal and perinatal brain injury can lead to congenital hemiplegia and brain MRI is the most useful tool to classify them with accuracy and to provide early prognostic information. Perinatal arterial ischemic stroke thus appears as the leading cause in term infants, whereas encephalopathy of prematurity is the most common cause in premature babies. Other causes include brain malformations, neonatal sinovenous thrombosis, parenchymal hemorrhage (for example due to coagulopathy or alloimmune thrombocytopenia) and the more recently described familial forms of porencephaly associated with mutations in the COL4A1 gene. In adjunction with pharmacologic treatment (botulinium neurotoxin injection), new evidence-based rehabilitational interventions, such as constraint-induced movement therapy and mirror therapy, are increasingly being used.

Mild hypothermia as a treatment for central nervous system injuries: Positive or negative effects.

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Darwazeh, Rami; Yan, Yi

2013-10-05

Besides local neuronal damage caused by the primary insult, central nervous system injuries may secondarily cause a progressive cascade of related events including brain edema, ischemia, oxida-tive stress, excitotoxicity, and dysregulation of calcium homeostasis. Hypothermia is a beneficial strategy in a variety of acute central nervous system injuries. Mild hypothermia can treat high intra-cranial pressure following traumatic brain injuries in adults. It is a new treatment that increases sur-vival and quality of life for patients suffering from ischemic insults such as cardiac arrest, stroke, and neurogenic fever following brain trauma. Therapeutic hypothermia decreases free radical produc-tion, inflammation, excitotoxicity and intracranial pressure, and improves cerebral metabolism after traumatic brain injury and cerebral ischemia, thus protecting against central nervous system dam-age. Although a series of pathological and physiological changes as well as potential side effects are observed during hypothermia treatment, it remains a potential therapeutic strategy for central nervous system injuries and deserves further study.

Enhanced expressions of microvascular smooth muscle receptors after focal cerebral ischemia occur via the MAPK MEK/ERK pathway

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Edvinsson Lars

2008-09-01

Full Text Available Abstract Background MEK1/2 is a serine/threonine protein that phosphorylates extracellular signal-regulated kinase (ERK1/2. Cerebral ischemia results in enhanced expression of cerebrovascular contractile receptors in the middle cerebral artery (MCA leading to the ischemic region. Here we explored the role of the MEK/ERK pathway in receptor expression following ischemic brain injury using the specific MEK1 inhibitor U0126. Methods and result Rats were subjected to a 2-h middle cerebral artery occlusion (MCAO followed by reperfusion for 48-h and the ischemic area was calculated. The expression of phosphorylated ERK1/2 and Elk-1, and of endothelin ETA and ETB, angiotensin AT1, and 5-hydroxytryptamine 5-HT1B receptors were analyzed with immunohistochemistry using confocal microscopy in cerebral arteries, microvessels and in brain tissue. The expression of endothelin ETB receptor was analyzed by quantitative Western blot. We demonstrate that there is an increase in the number of contractile smooth muscle receptors in the MCA and in micro- vessels within the ischemic region. The enhanced expression occurs in the smooth muscle cells as verified by co-localization studies. This receptor upregulation is furthermore associated with enhanced expression of pERK1/2 and of transcription factor pElk-1 in the vascular smooth muscle cells. Blockade of transcription with the MEK1 inhibitor U0126, given at the onset of reperfusion or as late as 6 hours after the insult, reduced transcription (pERK1/2 and pElk-1, the enhanced vascular receptor expression, and attenuated the cerebral infarct and improved neurology score. Conclusion Our results show that MCAO results in upregulation of cerebrovascular ETB, AT1 and 5-HT1B receptors. Blockade of this event with a MEK1 inhibitor as late as 6 h after the insult reduced the enhanced vascular receptor expression and the associated cerebral infarction.

Advances of 11C-flumazenil receptor imaging in ischemic penumbra

International Nuclear Information System (INIS)

Zhang Jun

2004-01-01

The ischemic penumbra is the target of therapy for ischemic stroke patients, so it is extremely important to investigate an imaging technique that may identify accurately the viability of cerebral tissues early. The neuroreceptor imaging with positron emission tomography has achieved some successes in this study field, in particular, the 11 C-flumazenil receptor imaging, which can not only differentiate between the neurons of functional impairment and those of morphological destruction, and then distinguish the ischemic penumbra from the irreversible damage tissues, but predict the malignant course of cerebral infarction. Consequently, these will help to select the patients benefiting from the intervention therapy and plan effectively the therapeutic strategies. (authors)

Niosomes of Ascorbic Acid and α-Tocopherol in the Cerebral Ischemia-Reperfusion Model in Male Rats

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Jaleh Varshosaz

2014-01-01

Full Text Available The objective of the present study was to prepare a stable iv injectable formulation of ascorbic acid and α-tocopherol in preventing the cerebral ischemia. Different niosomal formulations were prepared by Span and Tween mixed with cholesterol. The physicochemical characteristics of niosomal formulations were evaluated in vitro. For in vivo evaluation, the rats were made ischemic by middle cerebral artery occlusion model for 30 min and the selected formulation was used for determining its neuroprotective effect against cerebral ischemia. Neuronal damage was evaluated by optical microscopy and transmission electron microscopy. The encapsulation efficiency of ascorbic acid was increased to more than 84% by remote loading method. The cholesterol content of the niosomes, the hydrophilicity potential of the encapsulated compounds, and the preparation method of niosomes were the main factors affecting the mean volume diameter of the prepared vesicles. High physical stability of the niosomes prepared from Span 40 and Span 60 was demonstrated due to negligible size change of vesicles during 6 months storage at 4–8°C. In vivo studies showed that ST60/Chol 35 : 35 : 30 niosomes had more neuroprotective effects against cerebral ischemic injuries in male rats than free ascorbic acid.

PET imaging of cerebral perfusion and oxygen consumption in acute ischemic stroke: Relation to outcome

International Nuclear Information System (INIS)

Marchal, G.; Serrati, C.; Rioux, P.; Petit-Taboue, M.C.; Viader, F.; Sayette, V. de la; Doze, F. le; Lonchon, P; Derlon, J.M.; Orgogozo, J.M.; Baron, J.C.

1993-01-01

The authors used positron emission tomography (PET) to assess the relation between combined imaging of cerebral blood flow and oxygen consumption 5-18 h after first middle cerebral artery (MCA) stroke and neurological outcome at 2 months. All 18 patients could be classified into three visually defined PET patterns of perfusion and oxygen consumption changes. Pattern 1 suggested extensive irreversible damage and was consistently associated with poor outcome. Pattern 2 suggested continuing ischemia and was associated with variable outcome. Pattern 3 with hyperperfusion and little or no metabolic alteration, was associated with excellent recovery, which suggests that early reperfusion is beneficial. This relation between PET and outcome was highly significant. The results suggest that within 5-18 h of stroke onset, PET is a good predictor of outcome in patterns 1 and 3, for which therapy seems limited. The absence of predictive value for pattern 2 suggests that it is due to a reversible ischemic state that is possibly amenable to therapy. These findings may have important implications for acute MCA stroke management and for patients' selection for therapeutic trials

Manejo da hipertensão arterial na isquemia cerebral aguda Management of arterial hypertension in patients with acute ischemic stroke

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WALTER JOSÉ FAGUNDES-PEREYRA

1999-12-01

Full Text Available OBJETIVO: Avaliar o nível de conhecimento dos médicos, através de sua conduta, em paciente com quadro de hipertensão arterial na fase aguda da isquemia cerebral. Também comentamos as principais condutas nesta fase, com ênfase na tensão arterial (TA. MÉTODO: Foram entrevistados 120 médicos da clínica médica e da cirurgia geral, em dez dos maiores Hospitais de Belo Horizonte, em 1997. Todos responderam a um questionário contendo um caso clínico de paciente hipertenso leve, admitido com quadro de isquemia cerebral e tensão arterial de 186x110 mmHg. Os profissionais deveriam optar por reduzir, aumentar ou manter a TA. RESULTADOS: Dos entrevistados, 38 (31,7% responderam que reduziriam os níveis tensionais, 82 (68,3% optaram pela manutenção e nenhum aumentaria (pPURPOSE: We aimed with study to assess the current clinical practice about the management of high blood pressure in patients in the acute phase of ischemic stroke. We also comment some topics of ischemic stroke treatment. METHODS: A case report of a patient admitted 8 hours after onset of ischemic stroke and with blood pressure of 186x110 mmHg was presented to 120 surgeons and clinician. They were asked to decide the best therapeutic option: to increase, decrease or maintenance blood pressure. RESULTS: Thirty-eight physicians (31,7% considered decreasing blood pressure the best therapeutics, 82 (68,3% considered maintenance and none decided to increase it (p < 0.05. There was no difference between the two specialties conduct. The physicians, with more than 10 years of graduation, had a tendency to decrease the blood pressure (p <0.05. CONCLUSION: The maintenance of blood pressure may present a sufficient blood support to compensate brain flow. A high percentage of the physicians (31,7% do not know about the current concepts of therapeutics considering hypertension in acute ischemic stroke. The development on special units to treat these patients ("stroke units" may eventually

The Long-Term Outcome Comparison of Different Time-Delayed Kallikrein Treatments in a Mouse Cerebral Ischemic Model

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Yaohui Ni

2018-01-01

Full Text Available Delayed administration of kallikrein after cerebral infarction can improve neurological function. However, the appropriate kallkrein treatment time after ischemic stroke has not been illuminated. In this study, we compared the long-term outcome among three kallikrein therapeutic regimens starting at different time points following mouse cerebral ischemia. Furthermore, the protective mechanisms involving neurogenesis, angiogenesis, and AKT-GSK3β-VEGF signaling pathway were analyzed. Human tissue kallikrein was injected through the tail vein daily starting at 8 h, 24 h, or 36 h after right middle cerebral artery occlusion (MCAO until the 28th day. Three therapeutic regimens all protected against neurological dysfunction, but kallikrein treatment starting at 8 h after MCAO had the best efficacy. Additionally, kallikrein treatment at 8 h after MCAO significantly enhanced cell proliferation including neural stem cell and induced differentiation of neural stem cell into mature neuron. Kallikrein treatment starting at 8 h also promoted more angiogenesis than other two treatment regimens, which was associated with AKT-GSK3β-VEGF signaling pathway. Thus, we confirm that three delayed kallikrein treatments provide protection against cerebral infarction and furthermore suggest that kallikrein treatment starting at 8 h had a better effect than that at 24 h and 36 h. These findings provide the experimental data contributing to better clinical application of exogenous kallikrein.

Sex-dependent effects of chronic psychosocial stress on myocardial sensitivity to ischemic injury.

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Rorabaugh, Boyd R; Krivenko, Anna; Eisenmann, Eric D; Bui, Albert D; Seeley, Sarah; Fry, Megan E; Lawson, Joseph D; Stoner, Lauren E; Johnson, Brandon L; Zoladz, Phillip R

2015-01-01

Individuals with post-traumatic stress disorder (PTSD) experience many debilitating symptoms, including intrusive memories, persistent anxiety and avoidance of trauma-related cues. PTSD also results in numerous physiological complications, including increased risk for cardiovascular disease (CVD). However, characterization of PTSD-induced cardiovascular alterations is lacking, especially in preclinical models of the disorder. Thus, we examined the impact of a psychosocial predator-based animal model of PTSD on myocardial sensitivity to ischemic injury. Male and female Sprague-Dawley rats were exposed to psychosocial stress or control conditions for 31 days. Stressed rats were given two cat exposures, separated by a period of 10 days, and were subjected to daily social instability throughout the paradigm. Control rats were handled daily for the duration of the experiment. Rats were tested on the elevated plus maze (EPM) on day 32, and hearts were isolated on day 33 and subjected to 20 min ischemia and 2 h reperfusion on a Langendorff isolated heart system. Stressed male and female rats gained less body weight relative to controls, but only stressed males exhibited increased anxiety on the EPM. Male, but not female, rats exposed to psychosocial stress exhibited significantly larger infarcts and attenuated post-ischemic recovery of contractile function compared to controls. Our data demonstrate that predator stress combined with daily social instability sex-dependently increases myocardial sensitivity to ischemic injury. Thus, this manipulation may be useful for studying potential mechanisms underlying cardiovascular alterations in PTSD, as well as sex differences in the cardiovascular stress response.

Effect of early rehabilitation training on oxygen free radical generation and nerve injury in patients with cerebral hemorrhage

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Zhao-Shu Liu

2017-08-01

Full Text Available Objective: To study the effect of early rehabilitation training combined with edaravone on oxygen free radical generation and nerve injury in patients with cerebral hemorrhage. Methods: A total of 56 patients with acute cerebral hemorrhage who were treated in Zigong Third People’s Hospital between July 2014 and March 2017 were selected and randomly divided into early rehabilitation group and routine rehabilitation group, the early rehabilitation group began the rehabilitation training 2 d after cerebral hemorrhage condition was stabilized, and routine rehabilitation group began the rehabilitation training 14 d after cerebral hemorrhage. Serum contents of oxygen free radicals, nerve injury markers and neurotrophic molecules were detected 28 d and 56 d after cerebral hemorrhage. Results: 28 d and 56 d after cerebral hemorrhage, serum MDA, AOPP, 8-OHdG, GFAP, NSE, Tf, Ft and S100B levels of early rehabilitation group were significantly lower than those of routine rehabilitation group while BDNF, NGF, NTF-α and IGF-I levels were significantly higher than those of routine rehabilitation group. Conclusion: Early rehabilitation training combined with edaravone for cerebral hemorrhage can inhibit the oxygen free radical generation, reduce the degree of nerve injury and improve the neurotrophic state.

The role of exogenous neural stem cells transplantation in cerebral ischemic stroke.

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Chen, Lukui; Qiu, Rong; Li, Lushen; He, Dan; Lv, Haiqin; Wu, Xiaojing; Gu, Ning

2014-11-01

To observe the effects of neural stem cells (NSCs) transplantation in rats' striatum and subventricular zone (SVZ) in rat models of focal cerebral ischemia and reperfusion. Hippocampus was extracted from fetal rats with 14 days of gestation. Suspension culture was used to isolate and culture the rat's NSCs. A cerebral ischemia and reperfusion rat's model was made on the left side of the brain through occlusion of the left middle cerebral artery. Neurological signs were assessed by Zea Longa's five-grade scale, with scores 1, 2, and 3 used to determine the successful establishment of the rat's model. The NSCs were stereotaxically injected into the left striatum 24 hours after the successful rat's model was built. Rats were then randomly divided into 5 groups, namely, normal group, sham operation group, ischemia group, PBS transplantation group, and NSCs transplantation group, each of which was observed on day 3, day 7, and day 14. The ischemia-related neurological deficits were assessed by using a 7-point evaluation criterion. Forelimb injuries were evaluated in all rats using the foot-fault approach. Infarct size changes were observed through TTC staining and cell morphology and structure in the infarct region were investigated by Nissl staining. Apoptosis and apoptosis-positive cell counts were studied by Tunel assay. Expressions of double-labeling positive cells in the striatum and subventricular zone (SVZ) were observed by BrdU/NeuN and BrdU/GFAP fluorescent double-labeling method and the number of positive cells in the striatum and SVZ was counted. Results from the differently treated groups showed that right hemiplegia occurred in the ischemia group, PBS transplantation group, and NSCs transplantation group in varying degrees. Compared with the former two groups, there was least hemiplegia in the NSCs transplantation group. The TTC staining assay showed that rats in the NSCs transplantation group had smaller infarct volume than those from the PBS

Continuous determination of optimal cerebral perfusion pressure in traumatic brain injury

NARCIS (Netherlands)

Aries, M.J.H.; Czosnyka, Marek; Budohoski, Karol P.; Steiner, Luzius A.; Lavinio, Andrea; Kolias, Angelos G.; Hutchinson, Peter J.; Brady, Ken M.; Menon, David K.; Pickard, John D.; Smielewski, Peter

Objectives: We have sought to develop an automated methodology for the continuous updating of optimal cerebral perfusion pressure (CPPopt) for patients after severe traumatic head injury, using continuous monitoring of cerebrovascular pressure reactivity. We then validated the CPPopt algorithm by

Endogenous Protection Derived from Activin A/Smads Transduction Loop Stimulated via Ischemic Injury in PC12 Cells

OpenAIRE

Mang, Jing; Mei, Chun-Li; Wang, Jiao-Qi; Li, Zong-Shu; Chu, Ting-Ting; He, Jin-Ting; Xu, Zhong-Xin

2013-01-01

Activin A (ActA), a member of transforming growth factor-beta (TGF-b) super- family, affects many cellular processes, including ischemic stroke. Though the neuroprotective effects of exogenous ActA on oxygen-glucose deprivation (OGD) injury have already been reported by us, the endogenous role of ActA remains poorly understood. To further define the role and mechanism of endogenous ActA and its signaling in response to acute ischemic damage, we used an OGD model in PC12 cells to simulate isch...

Diaschisis with cerebral infarction

Energy Technology Data Exchange (ETDEWEB)

Slater, R.; Reivich, M.; Goldberg, H.; Banka, R.; Greenberg, J.

1977-01-01

Fifteen patients admitted to Philadelphia General Hospital with acute strokes had repeated measurements of cerebral blood flow measured by the /sup 133/X inhalation method. A progressive decline in cerebral blood flow in both hemispheres was observed during the first week after infarction in twelve of these patients. This decline could be partially explained by loss of autoregulation, but could not be correlated with level of consciousness, clinical status of PCO2. This progressive decline in flow in the non-ischemic hemisphere indicates a process more complex than a simple destruction of axonal afferants to neurons as implied by the term diaschisis. The flow changes in the non-ischemic hemisphere are likely caused by a combination of the immediate effects of decreased neuronal stimulation modified by loss of autoregulation, release of vasoactive substances, cerebral edema, and other factors.

A Case Of Transient Ischemic Attack Presenting As Hemichroea

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Hasan Hüseyin Özdemir

2013-12-01

Full Text Available Chorea is defined as; involuntary movements of the distal parts of limbs which have arrhythmic, rapid, bouncing or smooth, simple or complex properties. Choreiform movements occur when putamen, globus pallidus and subthalamic nucleus are affected. Chorea can be observed during the course of metabolic and vascular diseases, neurodegenerative or hereditary diseases. Chorea may be a rare symptom of cerebral hypoperfusion. Transient ischemic attack is an event that occurs in short term characterized by a temporary ischemia of brain. A wide variety of symptoms can be seen depending on the localization of cerebral hypoperfusion. Hemichorea is a very rare finding observed during transient ischemic attacks. In this article hemichorea in a case of symptomatic transient ischemic attack is discussed with relevant literature.

Multi-site laser Doppler flowmetry for assessing collateral flow in experimental ischemic stroke: Validation of outcome prediction with acute MRI.

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Cuccione, Elisa; Versace, Alessandro; Cho, Tae-Hee; Carone, Davide; Berner, Lise-Prune; Ong, Elodie; Rousseau, David; Cai, Ruiyao; Monza, Laura; Ferrarese, Carlo; Sganzerla, Erik P; Berthezène, Yves; Nighoghossian, Norbert; Wiart, Marlène; Beretta, Simone; Chauveau, Fabien

2017-06-01

High variability in infarct size is common in experimental stroke models and affects statistical power and validity of neuroprotection trials. The aim of this study was to explore cerebral collateral flow as a stratification factor for the prediction of ischemic outcome. Transient intraluminal occlusion of the middle cerebral artery was induced for 90 min in 18 Wistar rats. Cerebral collateral flow was assessed intra-procedurally using multi-site laser Doppler flowmetry monitoring in both the lateral middle cerebral artery territory and the borderzone territory between middle cerebral artery and anterior cerebral artery. Multi-modal magnetic resonance imaging was used to assess acute ischemic lesion (diffusion-weighted imaging, DWI), acute perfusion deficit (time-to-peak, TTP), and final ischemic lesion at 24 h. Infarct volumes and typology at 24 h (large hemispheric versus basal ganglia infarcts) were predicted by both intra-ischemic collateral perfusion and acute DWI lesion volume. Collateral flow assessed by multi-site laser Doppler flowmetry correlated with the corresponding acute perfusion deficit using TTP maps. Multi-site laser Doppler flowmetry monitoring was able to predict ischemic outcome and perfusion deficit in good agreement with acute MRI. Our results support the additional value of cerebral collateral flow monitoring for outcome prediction in experimental ischemic stroke, especially when acute MRI facilities are not available.

Memantine mediates neuroprotection via regulating neurovascular unit in a mouse model of focal cerebral ischemia.

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Chen, Zheng-Zhen; Yang, Dan-Dan; Zhao, Zhan; Yan, Hui; Ji, Juan; Sun, Xiu-Lan

2016-04-01

Memantine is a low-moderate affinity and uncompetitive N-methyl-d-aspartate receptor (NMDAR) antagonist, which is also a potential neuroprotectant in acute ischemic stroke for its particular action profiles. The present study was to reveal the mechanisms involved in the neuroprotection of memantine. We used a mouse model of permanent focal cerebral ischemia via middle cerebral artery occlusion to verify our hypothesis. 2,3,5-Triphenyltetrazolium chloride staining was used to compare infarct size. The amount of astrocytes and the somal volume of the microglia cell body were analyzed by immunohistochemistry and stereological estimates. Western blotting was used to determine the protein expressions. Memantine prevented cerebral ischemia-induced brain infarct and neuronal injury, and reduced oxygen-glucose deprivation-induced cortical neuronal apoptosis. Moreover, memantine reduced the amount of the damaged astrocytes and over activated microglia after 24h of ischemia. In the early phase of ischemia, higher production of MMP-9 was observed, and thereby collagen IV was dramatically disrupted. Meanwhile, the post-synaptic density protein 95(PSD-95) was also severely cleavaged. Memantine decreased MMP-9 secretion, prevented the degradation of collagen IV in mouse brain. PSD-95 cleavage was also inhibited by memantine. These results suggested that memantine exerted neuroprotection effects in acute ischemic brain damage, partially via improving the functions of neurovascular unit. Taking all these findings together, we consider that memantine might be a promising protective agent against ischemic stroke. Copyright © 2016 Elsevier Inc. All rights reserved.

Acute posterior multifocal placoid pigment epitheliopathy associated with cerebral vasculitis.

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Weinstein, J M; Bresnick, G H; Bell, C L; Roschmann, R A; Brooks, B R; Strother, C M

1988-09-01

Acute multifocal posterior placoid pigment epitheliopathy (APMPPE) is an unusual self-limited retinal disorder that has been associated with various systemic complications. To our knowledge, three prior cases associated with cerebral vasculitis have been described. This article describes a patient with APMPPE and angiographically documented cerebral vasculitis who was notable because of (a) the presence of two different cerebral ischemic events, occurring 1 month apart, and (b) the long latency (3 months) between the onset of ocular symptoms and the second cerebral ischemic event. Recognition of the association between APMPPE and cerebral vasculitis may permit early treatment of CNS involvement and prevention of morbidity.

Comparison of MR imaging after administration of dysprosium-based magnetic-susceptibility contrast media with diffusion-weighted MR imaging in evaluation of regional cerebral ischemia

International Nuclear Information System (INIS)

Moseley, M.E.; Kucharczyk, J.; Kurhanewicz, J.; Mintorovitch, J.; Cohen, Y.; Rocklage, S.; Quay, S.C.; Norman, D.

1989-01-01

This paper reports on a study to establish whether a nonionic T2-shortening contrast agent, Dy-DTPA-bis(methylamide) (Dy-DTPA-BMA), would facilitate early detection of stroke-induced cerebral perfusion deficits. The sensitivity of susceptibility-enhanced MR imaging was compared with that of diffusion-weighted MR imaging in the same cats subjected to unilateral occlusion of the middle cerebral artery (MCA). A 2-T unit, equipped with self-shielded gradient coils (± 20 G/cm, 15-cm bore size), was used in conjunction with an 8.5-cm inner diameter low-pass bird cage proton imaging coil. Diffusion-weighted images displayed increased signal intensity in the ischemic MCA territory less than 1 hour after occlusion, whereas T2-weighted MR images without contrast enhancement usually failed to depict injury for 2--3 hours after toke. With contrast administration (0.5 mmoles/kg of Dy-DTPA-BMA), however, T2-weighted images revealed perfusion deficits (hyperintensity) within 1 hour after MCA occlusion, and these corresponded to the anatomic regions of ischemic injury shown on diffusion-weighted MR images

Post traumatic brain perfusion SPECT analysis using reconstructed ROI maps of radioactive microsphere derived cerebral blood flow and statistical parametric mapping.

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McGoron, Anthony J; Capille, Michael; Georgiou, Michael F; Sanchez, Pablo; Solano, Juan; Gonzalez-Brito, Manuel; Kuluz, John W

2008-02-29

Assessment of cerebral blood flow (CBF) by SPECT could be important in the management of patients with severe traumatic brain injury (TBI) because changes in regional CBF can affect outcome by promoting edema formation and intracranial pressure elevation (with cerebral hyperemia), or by causing secondary ischemic injury including post-traumatic stroke. The purpose of this study was to establish an improved method for evaluating regional CBF changes after TBI in piglets. The focal effects of moderate traumatic brain injury (TBI) on cerebral blood flow (CBF) by SPECT cerebral blood perfusion (CBP) imaging in an animal model were investigated by parallelized statistical techniques. Regional CBF was measured by radioactive microspheres and by SPECT 2 hours after injury in sham-operated piglets versus those receiving severe TBI by fluid-percussion injury to the left parietal lobe. Qualitative SPECT CBP accuracy was assessed against reference radioactive microsphere regional CBF measurements by map reconstruction, registration and smoothing. Cerebral hypoperfusion in the test group was identified at the voxel level using statistical parametric mapping (SPM). A significant area of hypoperfusion (P TBI. Statistical mapping of the reference microsphere CBF data confirms a focal decrease found with SPECT and SPM. The suitability of SPM for application to the experimental model and ability to provide insight into CBF changes in response to traumatic injury was validated by the SPECT SPM result of a decrease in CBP at the left parietal region injury area of the test group. Further study and correlation of this characteristic lesion with long-term outcomes and auxiliary diagnostic modalities is critical to developing more effective critical care treatment guidelines and automated medical imaging processing techniques.

Computed microtomography visualization and quantification of mouse ischemic brain lesion by nonionic radio contrast agents.

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Dobrivojević, Marina; Bohaček, Ivan; Erjavec, Igor; Gorup, Dunja; Gajović, Srećko

2013-02-01

To explore the possibility of brain imaging by microcomputed tomography (microCT) using x-ray contrasting methods to visualize mouse brain ischemic lesions after middle cerebral artery occlusion (MCAO). Isolated brains were immersed in ionic or nonionic radio contrast agent (RCA) for 5 days and subsequently scanned using microCT scanner. To verify whether ex-vivo microCT brain images can be used to characterize ischemic lesions, they were compared to Nissl stained serial histological sections of the same brains. To verify if brains immersed in RCA may be used afterwards for other methods, subsequent immunofluorescent labeling with anti-NeuN was performed. Nonionic RCA showed better gray to white matter contrast in the brain, and therefore was selected for further studies. MicroCT measurement of ischemic lesion size and cerebral edema significantly correlated with the values determined by Nissl staining (ischemic lesion size: P=0.0005; cerebral edema: P=0.0002). Brain immersion in nonionic RCA did not affect subsequent immunofluorescent analysis and NeuN immunoreactivity. MicroCT method was proven to be suitable for delineation of the ischemic lesion from the non-infarcted tissue, and quantification of lesion volume and cerebral edema.

The correlation of insulin resistance with the cerebral injury and stress reaction in patients with traumatic brain injury

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Zhan Lan

2017-04-01

Full Text Available Objective: To study the correlation of insulin resistance with the cerebral injury and stress reaction in patients with traumatic brain injury (TBI. Methods: 78 patients who were diagnosed with acute traumatic brain injury in our hospital between May 2014 and August 2016 were selected as the TBI group, and 90 healthy volunteers who received physical examination during the same period were selected as the control group. The peripheral blood was collected to detect glucose, insulin and nerve injury marker molecules, stress hormones as well as oxidative stress reaction products, and the insulin resistance index (HOMA-IR was calculated. Results: The HOMA-IR index of TBI group was significantly higher than that of control group (P<0.05; serum neuron-specific enolase (NSE, ubiquitin carboxy-terminal hydrolase L1 (UCH-L1, S100β, myelin basic protein (MBP, glucagon, growth hormone, cortisol, malondialdehyde (MDA and 8-hydroxy-deoxyguanosine (8-OHdGlevels of TBI group were significantly higher than those of control group (P<0.05; serum NSE, UCH-L1, S100β, MBP, glucagon, growth hormone, cortisol, MDA and 8-OHdG levels of patients with high HOMA-IR were significantly higher than those of patients with low HOMA-IR (P<0.05. Conclusion: The insulin resistance increases significantly in patients with traumatic brain injury, and is closely related to the degree of cerebral injury and stress reaction.

Astragaloside IV for Experimental Focal Cerebral Ischemia: Preclinical Evidence and Possible Mechanisms

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Hui-Lin Wang

2017-01-01

Full Text Available Astragaloside IV (AST-IV is a principal component of Radix Astragali seu Hedysari (Huangqi and exerts potential neuroprotection in experimental ischemic stroke. Here, we systematically assessed the effectiveness and possible mechanisms of AST-IV for experimental acute ischemic stroke. An electronic search in eight databases was conducted from inception to March 2016. The study quality score was evaluated using the CAMARADES. Rev Man 5.0 software was used for data analyses. Thirteen studies with 244 animals were identified. The study quality score of included studies ranged from 3/10 to 8/10. Eleven studies showed significant effects of AST-IV for ameliorating the neurological function score (P<0.05; seven studies for reducing the infarct volume (P<0.05; and three or two studies for reducing the brain water content and Evans blue leakage (P<0.05, respectively, compared with the control. The mechanisms of AST-IV for ischemic stroke are multiple such as antioxidative/nitration stress reaction, anti-inflammatory, and antiapoptosis. In conclusion, the findings of present study indicated that AST-IV could improve neurological deficits and infarct volume and reduce the blood-brain barrier permeability in experimental cerebral ischemia despite some methodological flaws. Thus, AST-IV exerted a possible neuroprotective effect during the cerebral ischemia/reperfusion injury largely through its antioxidant, anti-inflammatory, and antiapoptosis properties.

Nanomedicine in cerebral palsy

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Balakrishnan, Bindu; Nance, Elizabeth; Johnston, Michael V; Kannan, Rangaramanujam; Kannan, Sujatha

2013-01-01

Cerebral palsy is a chronic childhood disorder that can have diverse etiologies. Injury to the developing brain that occurs either in utero or soon after birth can result in the motor, sensory, and cognitive deficits seen in cerebral palsy. Although the etiologies for cerebral palsy are variable, neuroinflammation plays a key role in the pathophysiology of the brain injury irrespective of the etiology. Currently, there is no effective cure for cerebral palsy. Nanomedicine offers a new frontier in the development of therapies for prevention and treatment of brain injury resulting in cerebral palsy. Nanomaterials such as dendrimers provide opportunities for the targeted delivery of multiple drugs that can mitigate several pathways involved in injury and can be delivered specifically to the cells that are responsible for neuroinflammation and injury. These materials also offer the opportunity to deliver agents that would promote repair and regeneration in the brain, resulting not only in attenuation of injury, but also enabling normal growth. In this review, the current advances in nanotechnology for treatment of brain injury are discussed with specific relevance to cerebral palsy. Future directions that would facilitate clinical translation in neonates and children are also addressed. PMID:24204146

Cerebral microdialysis and PtiO2 to decide unilateral decompressive craniectomy after brain gunshot

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Boret Henry

2012-01-01

Full Text Available Decompressive craniectomy (DC following brain injury can induce complications (hemorrhage, infection, and hygroma. It is then considered as a last-tier therapy, and can be deleteriously delayed. Focal neuromonitoring (microdialysis and PtiO2 can help clinicians to decide bedside to perform DC in case of intracranial pressure (ICP around 20 to 25 mmHg despite maximal medical treatment. This was the case of a hunter, brain injured by gunshot. DC was performed at day 6, because of unstable ICP, ischemic trend of PtiO2, and decreased cerebral glucose but normal lactate/pyruvate ratio. His evolution was good despite left hemiplegia due to initial injury.

Improvement in regional CBF by L-serine contributes to its neuroprotective effect in rats after focal cerebral ischemia.

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Tao-Jie Ren

Full Text Available To investigate the mechanisms underlying the neuroprotective effect of L-serine, permanent focal cerebral ischemia was induced by occlusion of the middle cerebral artery while monitoring cerebral blood flow (CBF. Rats were divided into control and L-serine-treated groups after middle cerebral artery occlusion. The neurological deficit score and brain infarct volume were assessed. Nissl staining was used to quantify the cortical injury. L-serine and D-serine levels in the ischemic cortex were analyzed with high performance liquid chromatography. We found that L-serine treatment: 1 reduced the neurological deficit score, infarct volume and cortical neuron loss in a dose-dependent manner; 2 improved CBF in the cortex, and this effect was inhibited in the presence of apamin plus charybdotoxin while the alleviation of both neurological deficit score and infarct volume was blocked; and 3 increased the amount of L-serine and D-serine in the cortex, and inhibition of the conversion of L-serine into D-serine by aminooxyacetic acid did not affect the reduction of neurological deficit score and infarct volume by L-serine. In conclusion, improvement in regional CBF by L-serine may contribute to its neuroprotective effect on the ischemic brain, potentially through vasodilation which is mediated by the small- and intermediate-conductance Ca(2+-activated K(+ channels on the cerebral blood vessel endothelium.

[Results of thrombolyses procedures in acute ischemic cerebral stroke realized in Kraków 2004-2007--Grant Ministry of Science and Information].

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Popiela, Tadeusz J; Urbanik, Andrzej; Słowik, Agnieszka

2010-01-01

To lower the number of complications of acute cerebral ischemic stroke and to reduce the time of rehabilitation in these patients it is necessary to induce treatment within the first 3 hours of the onset of the stroke. Early intervention however, is possible only in cases with the confirm localized ischemic focus visualized in one of the diagnostic imaging methods. The most widespread is CT, hovewer the first symptoms of ischemic stroke can be seen not beforel2 hours of the onset. The study evaluated the effectiveness of early diagnostics of ischemic stroke using perfusion CT (pCT) with subsequent intravenous or intra-arterial thrombolysis. The patients with ischemic stroke confirmed by pCT and qualified to thrombolysis in the first 3 hours of the onset of the stroke were randomly selected to intravenous or intra-arterial thrmobolysis. Those, who were 3 to 6 hours of the onset of the stroke were qualified to intra-arterial thrombolysis. A study group consisted of 377 patients hospitalized due to ischemic stroke. Of these pCT was performed in 76 cases, intravenous thrombolysis in 4 and intra-arterial thrombolysis in 2. Clinical condition substantially improved in 3 patients. Obtained results indicate the necessity to introduce pCT to the routine diagnostics of the acute ischemic stroke. A small number of patients eligible for thrombolysis does not allow to compare the effectiveness of intra-arterial and intravenous thrombolysis, however the project allowed to work out the efficient system of diagnostics and treatment of the acute ischemic stroke in the area of Krakow based on the standards used in the European countries.

Exercise preconditioning improves behavioral functions following transient cerebral ischemia induced by 4-vessel occlusion (4-VO) in rats.

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Tahamtan, Mahshid; Allahtavakoli, Mohammad; Abbasnejad, Mehdi; Roohbakhsh, Ali; Taghipour, Zahra; Taghavi, Mohsen; Khodadadi, Hassan; Shamsizadeh, Ali

2013-12-01

There is evidence that exercise decreases ischemia/reperfusion injury in rats. Since behavioral deficits are the main outcome in patients after stroke, our study was designed to investigate whether exercise preconditioning improves the acute behavioral functions and also brain inflammatory injury following cerebral ischemia. Male rats weighing 250-300 g were randomly allocated into five experimental groups. Exercise was performed on a treadmill 30min/day for 3 weeks. Ischemia was induced by 4-vessel occlusion method. Recognition memory was assessed by novel object recognition task (NORT) and step-through passive avoidance task. Sensorimotor function and motor movements were evaluated by adhesive removal test and ledged beam-walking test, respectively. Brain inflammatory injury was evaluated by histological assessment. In NORT, the discrimination ratio was decreased after ischemia (P test, a significant reduction in response latency was observed in the ischemic group. Exercise preconditioning significantly decreased the response latency in the ischemic rats (P test, latency to touch and remove the sticky labels from forepaw was increased following induction of ischemia (all P beam-walking test, the slip ratio was increased following ischemia (P < 0.05).  In the ischemia group, marked neuronal injury in hippocampus was observed. These neuropathological changes were attenuated by exercise preconditioning (P < 0.001). Our results showed that exercise preconditioning improves behavioral functions and maintains more viable cells in the dorsal hippocampus of the ischemic brain.

A novel therapy to attenuate acute kidney injury and ischemic allograft damage after allogenic kidney transplantation in mice.

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Faikah Gueler

Full Text Available Ischemia followed by reperfusion contributes to the initial damage to allografts after kidney transplantation (ktx. In this study we tested the hypothesis that a tetrapeptide EA-230 (AQGV, might improve survival and attenuate loss of kidney function in a mouse model of renal ischemia/reperfusion injury (IRI and ischemia-induced delayed graft function after allogenic kidney transplantation. IRI was induced in male C57Bl/6N mice by transient bilateral renal pedicle clamping for 35 min. Treatment with EA-230 (20-50mg/kg twice daily i.p. for four consecutive days was initiated 24 hours after IRI when acute kidney injury (AKI was already established. The treatment resulted in markedly improved survival in a dose dependent manner. Acute tubular injury two days after IRI was diminished and tubular epithelial cell proliferation was significantly enhanced by EA-230 treatment. Furthermore, CTGF up-regulation, a marker of post-ischemic fibrosis, at four weeks after IRI was significantly less in EA-230 treated renal tissue. To learn more about these effects, we measured renal blood flow (RBF and glomerular filtration rate (GFR at 28 hours after IRI. EA-230 improved both GFR and RBF significantly. Next, EA-230 treatment was tested in a model of ischemia-induced delayed graft function after allogenic kidney transplantation. The recipients were treated with EA-230 (50 mg/kg twice daily i.p. which improved renal function and allograft survival by attenuating ischemic allograft damage. In conclusion, EA-230 is a novel and promising therapeutic agent for treating acute kidney injury and preventing IRI-induced post-transplant ischemic allograft injury. Its beneficial effect is associated with improved renal perfusion after IRI and enhanced regeneration of tubular epithelial cells.

Cerebral microbleeds are not associated with long-term cognitive outcome in patients with transient ischemic attack or minor stroke.

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Brundel, Manon; Kwa, Vincent I H; Bouvy, Willem H; Algra, Ale; Kappelle, L Jaap; Biessels, Geert Jan

2014-01-01

Cerebral microbleeds have been related to cerebrovascular disease and dementia. They occur more frequently in patients with ischemic stroke than in the general population, but their relation to cognition in these patients is uncertain, particularly in the long run. We examined the relationship between microbleeds in patients with a transient ischemic attack (TIA) or minor ischemic stroke, and cognitive performance 4 years later. Participants were recruited from a prospective multicenter cohort of patients with a TIA or minor ischemic stroke (n=397). They underwent magnetic resonance imaging (MRI), including a T2*-weighted sequence, within 3 months after their ischemic event. Microbleeds, atrophy, lacunae and white matter hyperintensities (WMH) were rated visually. Cognitive status was examined in 94% of all patients who were still alive after a mean interval of 3.8 years by the Dutch version of the Telephone Interview for Cognitive Status (TICS; n=280) or by an Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) obtained from a close relative if a TICS could not be obtained (n=48). The relationship between presence of microbleeds and TICS or IQCODE score was assessed with linear regression analyses adjusted for age, sex, educational level and time interval between MRI and cognitive evaluation. The mean age was 65±12 years at inclusion. The vascular event at inclusion was a TIA in 170 patients (52%) and a minor ischemic stroke in 155 patients (47%). Microbleeds were present in 11.6% of the patients. Patients with microbleeds were significantly older than patients without microbleeds (70±9 vs. 64±12 years), more often had hypertension, and had more cerebral atrophy, WMH and lacunae on MRI (all pTICS score was 35.3±5.9 for patients with microbleeds (n=29) and 34.6±5.2 for patients without microbleeds (n=251); the adjusted mean difference (95% CI) was 1.69 (-0.01 to 3.38). The total IQCODE score was 66.0±10.8 for patients with microbleeds (n=9

Early Recurrence and Cerebral Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation: Effect of Anticoagulation and Its Timing: The RAF Study.

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Paciaroni, Maurizio; Agnelli, Giancarlo; Falocci, Nicola; Caso, Valeria; Becattini, Cecilia; Marcheselli, Simona; Rueckert, Christina; Pezzini, Alessandro; Poli, Loris; Padovani, Alessandro; Csiba, Laszló; Szabó, Lilla; Sohn, Sung-Il; Tassinari, Tiziana; Abdul-Rahim, Azmil H; Michel, Patrik; Cordier, Maria; Vanacker, Peter; Remillard, Suzette; Alberti, Andrea; Venti, Michele; Scoditti, Umberto; Denti, Licia; Orlandi, Giovanni; Chiti, Alberto; Gialdini, Gino; Bovi, Paolo; Carletti, Monica; Rigatelli, Alberto; Putaala, Jukka; Tatlisumak, Turgut; Masotti, Luca; Lorenzini, Gianni; Tassi, Rossana; Guideri, Francesca; Martini, Giuseppe; Tsivgoulis, Georgios; Vadikolias, Kostantinos; Liantinioti, Chrissoula; Corea, Francesco; Del Sette, Massimo; Ageno, Walter; De Lodovici, Maria Luisa; Bono, Giorgio; Baldi, Antonio; D'Anna, Sebastiano; Sacco, Simona; Carolei, Antonio; Tiseo, Cindy; Acciarresi, Monica; D'Amore, Cataldo; Imberti, Davide; Zabzuni, Dorjan; Doronin, Boris; Volodina, Vera; Consoli, Domenico; Galati, Franco; Pieroni, Alessio; Toni, Danilo; Monaco, Serena; Baronello, Mario Maimone; Barlinn, Kristian; Pallesen, Lars-Peder; Kepplinger, Jessica; Bodechtel, Ulf; Gerber, Johannes; Deleu, Dirk; Melikyan, Gayane; Ibrahim, Faisal; Akhtar, Naveed; Mosconi, Maria Giulia; Bubba, Valentina; Silvestri, Ilenia; Lees, Kennedy R

2015-08-01

The best time for administering anticoagulation therapy in acute cardioembolic stroke remains unclear. This prospective cohort study of patients with acute stroke and atrial fibrillation, evaluated (1) the risk of recurrent ischemic event and severe bleeding; (2) the risk factors for recurrence and bleeding; and (3) the risks of recurrence and bleeding associated with anticoagulant therapy and its starting time after the acute stroke. The primary outcome of this multicenter study was the composite of stroke, transient ischemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding and major extracranial bleeding within 90 days from acute stroke. Of the 1029 patients enrolled, 123 had 128 events (12.6%): 77 (7.6%) ischemic stroke or transient ischemic attack or systemic embolism, 37 (3.6%) symptomatic cerebral bleeding, and 14 (1.4%) major extracranial bleeding. At 90 days, 50% of the patients were either deceased or disabled (modified Rankin score ≥3), and 10.9% were deceased. High CHA2DS2-VASc score, high National Institutes of Health Stroke Scale, large ischemic lesion and type of anticoagulant were predictive factors for primary study outcome. At adjusted Cox regression analysis, initiating anticoagulants 4 to 14 days from stroke onset was associated with a significant reduction in primary study outcome, compared with initiating treatment before 4 or after 14 days: hazard ratio 0.53 (95% confidence interval 0.30-0.93). About 7% of the patients treated with oral anticoagulants alone had an outcome event compared with 16.8% and 12.3% of the patients treated with low molecular weight heparins alone or followed by oral anticoagulants, respectively (P=0.003). Acute stroke in atrial fibrillation patients is associated with high rates of ischemic recurrence and major bleeding at 90 days. This study has observed that high CHA2DS2-VASc score, high National Institutes of Health Stroke Scale, large ischemic lesions, and type of anticoagulant administered

Evaluation of asymmetries of blood flow rate and of circulation time by intravenous radionuclide cerebral angiography in patients with ischemic completed stroke.

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Bartolini, A; Primavera, A; Gasparetto, B

1984-12-01

155 patients with ischemic completed stroke of varying severity and outcome have been evaluated by radionuclide cerebral angiography with analysis of regional time-activity curves. Two parameters have been evaluated: area under the upslope of the curve (Aup) reflecting regional blood flow rate and moment of the whole curve reflecting tracer circulation time (rABCT) Combination of these two methods ensured increased detection of perfusion asymmetries.

Systematic Analysis of RNA Regulatory Network in Rat Brain after Ischemic Stroke

Directory of Open Access Journals (Sweden)

Juan Liu

2018-01-01

Full Text Available Although extensive studies have identified large number of microRNAs (miRNAs and long noncoding RNAs (lncRNAs in ischemic stroke, the RNA regulation network response to focal ischemia remains poorly understood. In this study, we simultaneously interrogate the expression profiles of lncRNAs, miRNAs, and mRNAs changes during focal ischemia induced by transient middle cerebral artery occlusion. A set of 1924 novel lncRNAs were identified and may involve brain injury and DNA repair as revealed by coexpression network analysis. Furthermore, many short interspersed elements (SINE mediated lncRNA:mRNA duplexes were identified, implying that lncRNAs mediate Staufen1-mediated mRNA decay (SMD which may play a role during focal ischemia. Moreover, based on the competitive endogenous RNA (ceRNA hypothesis, a stroke regulatory ceRNA network which reveals functional lncRNA:miRNA:mRNA interactions was revealed in ischemic stroke. In brief, this work reports a large number of novel lncRNAs responding to focal ischemia and constructs a systematic RNA regulation network which highlighted the role of ncRNAs in ischemic stroke.

In vivo measurements of cerebral metabolic abnormalities by proton spectroscopy after a transient ischemic attack revealing an internal carotid stenosis > 70%; Anomalies metaboliques cerebrales mesurees in vivo par la spectroscopie du proton dans les accidents ischemiques transitoires revelant une stenose de la carotide interne superieure a 70%

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Giroud, M.; Becker, F.; Lemesle, M.; Walker, P.; Guy, F.; Martin, D.; Baudouin, N.; Brunotte, F.; Dumas, R. [Centre Hospitalier Universitaire, 21 -Dijon (France)

1996-06-01

Aims: The aim of this work is to look for cerebral metabolic abnormalities within the first 3 days after a transient ischemic attack revealing an internal carotid stenosis > 70 %. Methods: Five patients with a transient ischemic attack lasting between 30 and 180 minutes, affecting sensory and motor brachio-facial territory, with or without aphasia. Were studied. A CT-scan, an EEG, a cervical Doppler ultrasound, a standard arteriography, a magnetic resonance imaging and a proton spectroscopy were performed within the cerebral area affected by the transient ischemic attack. We measured 2 markers: N-acetyl-aspartate, the marker of the neuronal mass, and lactate, the marker of anaerobe metabolism. In each case, a contralateral internal stenosis was diagnosed by cervical Doppler ultrasound and standard arteriography. No cerebral infarction was observed. Results: With the affected cerebral area defined according to clinical and EEG features, proton spectroscopy showed a significant rise of lactate, without any change in N-acetyl-aspartate levels. Conclusions: Within the first 3 days after a transient ischemic attack, there is a significant risk of lactate inside the affected cerebral area. This change may reflect a localized and transient hypoperfusion, but long enough to induce a rise of lactate but not sufficient to produce a cerebral infarct. This area is probably at risk to induce cerebral infarct. This data lead us to study the metabolic change induced by the asymptomatic internal carotid stenosis. (authors). 18 refs.

Transient ischemic attacks with and without a relevant infarct on computed tomographic scans cannot be distinguished clinically. Dutch Transient Ischemic Attack Study Group

NARCIS (Netherlands)

Koudstaal, P. J.; van Gijn, J.; Lodder, J.; Frenken, W. G.; Vermeulen, M.; Franke, C. L.; Hijdra, A.; Bulens, C.

1991-01-01

We prospectively studied clinical and computed tomographic (CT) scan findings in 79 patients with a transient ischemic attack (TIA) and a relevant cerebral infarction on CT, also known as cerebral infarction with transient signs (CITS). We compared the results with those of 527 concurrent patients

DNA damage response in nephrotoxic and ischemic kidney injury

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Yan, Mingjuan; Tang, Chengyuan [Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011 (China); Ma, Zhengwei [Department of Cellular Biology & Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, GA 30912 (United States); Huang, Shuang [Department of Anatomy and Cell Biology, University of Florida College of Medicine, Gainesville, FL (United States); Dong, Zheng, E-mail: zdong@augusta.edu [Department of Nephrology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011 (China); Department of Cellular Biology & Anatomy, Medical College of Georgia at Augusta University and Charlie Norwood VA Medical Center, Augusta, GA 30912 (United States)

2016-12-15

DNA damage activates specific cell signaling cascades for DNA repair, cell cycle arrest, senescence, and/or cell death. Recent studies have demonstrated DNA damage response (DDR) in experimental models of acute kidney injury (AKI). In cisplatin-induced AKI or nephrotoxicity, the DDR pathway of ATR/Chk2/p53 is activated and contributes to renal tubular cell apoptosis. In ischemic AKI, DDR seems more complex and involves at least the ataxia telangiectasia mutated (ATM), a member of the phosphatidylinositol 3-kinase-related kinase (PIKK) family, and p53; however, while ATM may promote DNA repair, p53 may trigger cell death. Targeting DDR for kidney protection in AKI therefore relies on a thorough elucidation of the DDR pathways in various forms of AKI.

Mortality study for a decade: ischemic stroke in the elderly.

Directory of Open Access Journals (Sweden)

Javier J. García Zacarías

2014-09-01

Full Text Available Cerebrovascular diseases are among the top three causes of death in Cuba and the world, about 80 % of these patients belong to Ischemic Stroke. The objective of this paper is to describe the clinical and developmental profile of patients who died of Ischemic Stroke. A descriptive, prospective research, cross- sectional study was made, the sample included all deaths from ischemic stroke at the University Hospital "Camilo Cienfuegos" Sancti Spiritus, between January 1st, 2001 and December 31, 2010, and persons over 60 years of age with necropsy performed. Atherothrombotic stroke was the most frequent category, the highest mortality rates were observed in persons over 80 years of age and in females, hypertension, ischemic heart disease and transient ischemic attack were the main significant medical history; most patients were admitted in the stroke unit and died in Middle Progressive Care, cerebral edema and intracranial hypertension and hypostatic bronchopne umonia were complications and specific main causes of most frequent death. Value of cerebral edema and hypostatic bronchopneumonia as clinical complications and causes of death in patients investigated is confirmed.

Ameliorating effects of traditional Chinese medicine preparation, Chinese materia medica and active compounds on ischemia/reperfusion-induced cerebral microcirculatory disturbances and neuron damage

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Sun, Kai; Fan, Jingyu; Han, Jingyan

2015-01-01

Ischemic stroke and ischemia/reperfusion (I/R) injury induced by thrombolytic therapy are conditions with high mortality and serious long-term physical and cognitive disabilities. They have a major impact on global public health. These disorders are associated with multiple insults to the cerebral microcirculation, including reactive oxygen species (ROS) overproduction, leukocyte adhesion and infiltration, brain blood barrier (BBB) disruption, and capillary hypoperfusion, ultimately resulting in tissue edema, hemorrhage, brain injury and delayed neuron damage. Traditional Chinese medicine (TCM) has been used in China, Korea, Japan and other Asian countries for treatment of a wide range of diseases. In China, the usage of compound TCM preparation to treat cerebrovascular diseases dates back to the Han Dynasty. Even thousands of years earlier, the medical formulary recorded many classical prescriptions for treating cerebral I/R-related diseases. This review summarizes current information and underlying mechanisms regarding the ameliorating effects of compound TCM preparation, Chinese materia medica, and active components on I/R-induced cerebral microcirculatory disturbances, brain injury and neuron damage. PMID:26579420

Forensic applications of cerebral single photon emission computed tomography in mild traumatic brain injury.

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Wortzel, Hal S; Filley, Christopher M; Anderson, C Alan; Oster, Timothy; Arciniegas, David B

2008-01-01

Traumatic brain injury (TBI) is a substantial source of mortality and morbidity world wide. Although most such injuries are relatively mild, accurate diagnosis and prognostication after mild TBI are challenging. These problems are complicated further when considered in medicolegal contexts, particularly civil litigation. Cerebral single photon emission computed tomography (SPECT) may contribute to the evaluation and treatment of persons with mild TBI. Cerebral SPECT is relatively sensitive to the metabolic changes produced by TBI. However, such changes are not specific to this condition, and their presence on cerebral SPECT imaging does not confirm a diagnosis of mild TBI. Conversely, the absence of abnormalities on cerebral SPECT imaging does not exclude a diagnosis of mild TBI, although such findings may be of prognostic value. The literature does not demonstrate consistent relationships between SPECT images and neuropsychological testing or neuropsychiatric symptoms. Using the rules of evidence shaped by Daubert v. Merrell Dow Pharmaceuticals, Inc., and its progeny to analyze the suitability of SPECT for forensic purposes, we suggest that expert testimony regarding SPECT findings should be admissible only as evidence to support clinical history, neuropsychological test results, and structural brain imaging findings and not as stand-alone diagnostic data.