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1.
J Cell Biochem ; 121(1): 43-48, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31599049

RESUMO

BACKGROUND: This study aimed to study the expression level of cofilin after electroacupuncture (EA) pretreatment, using ischemic brain injury model in mice. In addition, infarct volume and neurological functions were measured to understand whether electroacupuncture stimulation could restore the functions of the brain. METHODS: Total of 36 mice was randomly divided into three groups: sham group, middle cerebral artery occlusion model (MACO), and middle cerebral artery occlusion model pretreated with EA (MACO + EA). Mice were stimulated at "Baihui (G20)" and "Dazhui (G14)" 24 hours before focal cerebral ischemia. Infarct volume and neuronal function of brain tissue were scored among different experimental groups. The expression level of cofilin and phosphocofilin of brain tissue were evaluated by using Western blot analysis. TUNEL assay was performed to determine the degree of cell apoptosis. RESULTS: Compared with the sham group, the level of cofilin was dramatically reduced in the MACO group. EA pretreatment could reduce the protein level of cofilin, while EA therapy could also upregulate the protein level of phosphocofilin. Improved neuronal function, smaller infarct volume, and reduced neuronal apoptosis were observed among the mice underwent EA before middle artery occlusion. CONCLUSION: Our results from Western blot analysis and TUNEL assay might suggest that the upregulation of cofilin was concerned with the EA protects rats from ischemic brain injury. Cofilin might be a potential target for developing drugs against brain ischemia.


Assuntos
Fatores de Despolimerização de Actina/metabolismo , Lesões Encefálicas/prevenção & controle , Isquemia Encefálica/metabolismo , Eletroacupuntura , Regulação da Expressão Gênica , Animais , Apoptose , Western Blotting , Encéfalo/metabolismo , Lesões Encefálicas/metabolismo , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média , Camundongos , Camundongos Endogâmicos C57BL , Artéria Cerebral Média/patologia , Neurônios/metabolismo , Estresse Oxidativo , Substâncias Protetoras
2.
Neurol Res ; 40(6): 499-507, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29576013

RESUMO

Objectives Intracranial atherosclerotic stenosis (ICAS) is one of the most common causes of stroke worldwide. We adapted a rat model of atherosclerosis to study brain intracranial atherosclerosis, and further investigated how omega-3 fatty acids (O3FA) attenuated the development of ICAS by reducing the generation of reactive oxygen species (ROS) and the activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activity. Methods Adult male Sprague-Dawley rats were divided into control normal-cholesterol or high-cholesterol diet groups with or without O3FA for up to 6 weeks. NG-nitro-L-arginine methyl ester (L-NAME, 3 mg/mL), a nitric oxide synthase inhibitor, was added to the drinking water of the high-cholesterol groups during the first 2 weeks. The rats received supplementation with O3FA (5 mg/kg/day) by gavage. At 3 and 6 weeks, we measured blood lipid levels, including low-density lipoprotein (LDL), cholesterol (CHO), triglycerides (TG), and high-density lipoprotein (HDL) as atherosclerotic blood markers. The lumen of middle cerebral artery (MCA) and the thickness of the vessel wall were assessed histologically. ROS production was measured. NOX activity and mRNA and protein expression of NOX subunits (p47phox, gp91phox, p22phox, and p67phox) were measured. Results A high-cholesterol diet exhibited a significant increase in the classic blood markers (LDL, CHO, and TG) for atherosclerosis, as well as a decrease in HDL. These markers were found to be progressively more severe with time. Additionally, increased lumen stenosis and intimal thickening were observed in the MCA for this group. Rats given O3FA demonstrated attenuation of blood lipid levels with an absence of morphological changes.O3FA significantly reduced ROS production and NOX activity in the brain. Moreover, O3FA decreased the mRNA and protein expression of the NOX subunits p47phox, gp91phox, and p67phox. Conclusions Long-term O3FA dietary supplementation prevents the development of intracranial atherosclerosis. This O3FA effect appears to be mediated by its attenuation of NOX subunit expression and NOX activity, therefore reducing ROS production. O3FA dietary supplement shows promising results in the prevention of ICAS.


Assuntos
Encéfalo/enzimologia , Ácidos Graxos Ômega-3/uso terapêutico , Arteriosclerose Intracraniana/dietoterapia , Arteriosclerose Intracraniana/enzimologia , NADPH Oxidases/metabolismo , Animais , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Constrição Patológica/dietoterapia , Constrição Patológica/enzimologia , Constrição Patológica/patologia , Modelos Animais de Doenças , Arteriosclerose Intracraniana/patologia , Lipídeos/sangue , Masculino , Microvasos/enzimologia , Microvasos/patologia , Artéria Cerebral Média/enzimologia , Artéria Cerebral Média/patologia , Tamanho do Órgão , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo
3.
Neuroscience ; 334: 226-235, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27522963

RESUMO

OBJECTIVES: Intracranial atherosclerotic stenosis (ICAS) is one of the most common causes of stroke worldwide and, in particular, has been implicated as a leading cause of recurrent ischemic stroke. We adapted a rat model of atherosclerosis to study brain intracranial atherosclerosis, and further investigated the effect of omega-3 fatty acids (O3FA) in attenuating development of ICAS. MATERIALS AND METHODS: Adult male Sprague-Dawley rats were divided into control normal-cholesterol or high-cholesterol diet groups with or without O3FA for up to 6weeks. During the first 2weeks, NG-nitro-l-arginine methyl ester (l-NAME, 3mg/mL) was added to the drinking water of the high-cholesterol groups. The rats received supplementation with O3FA (5mg/kg/day) by gavages. Blood lipids including low density lipoprotein (LDL), cholesterol (CHO), triglycerides (TG) and high density lipoprotein (HDL) were measured at 3 and 6weeks. The lumen of middle cerebral artery (MCA) and the thickness of the vessel wall were assessed. Inflammatory molecular markers were assessed by Western blot. RESULTS: A high-cholesterol diet exhibited a significant increase in the classic blood markers (LDL, CHO, and TG) for atherosclerosis, as well as a decrease in HDL. These markers were found to be progressively more severe with time. Lumen stenosis and intimal thickening were increased in MCA. O3FA showed attenuation of blood lipids with an absence of morphological changes. O3FA significantly reduced the inflammatory marker CD68 in MCA and prevented monocyte chemotactic protein (MCP-1) and interferon-γ (IFN-γ) expression in the brain. O3FA similarly decreased inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL-6), markers affiliated with monocyte activity in atherosclerosis. Furthermore, O3FA significantly inhibited the expression of vascular cell adhesion molecule-1 (VCAM-1), a marker for endothelial activation. Lastly, O3FA increased ATP-binding cassette transporter A1 (ABCA1) protein expression via silent information regulator 1 (SIRT1) activation, thus increasing cholesterol efflux from macrophages to HDL. CONCLUSIONS: Long-term O3FA dietary supplementation prevents the development of intracranial atherosclerosis. This O3FA effect appears to be mediated by its prevention of macrophage infiltration into the vessel wall, therefore reducing inflammation and intimal thickening. While similar effects in humans need to be determined, O3FA dietary supplement shows promising results in the prevention of ICAS.


Assuntos
Suplementos Nutricionais , Ácidos Graxos Ômega-3/administração & dosagem , Arteriosclerose Intracraniana/prevenção & controle , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Western Blotting , Encéfalo/irrigação sanguínea , Encéfalo/imunologia , Encéfalo/patologia , Quimiocina CCL2/metabolismo , Colesterol/administração & dosagem , Colesterol/efeitos adversos , Colesterol/sangue , Constrição Patológica/sangue , Constrição Patológica/imunologia , Constrição Patológica/patologia , Constrição Patológica/prevenção & controle , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Interleucina-6/metabolismo , Arteriosclerose Intracraniana/sangue , Arteriosclerose Intracraniana/imunologia , Arteriosclerose Intracraniana/patologia , Masculino , Artéria Cerebral Média/patologia , Ratos Sprague-Dawley , Sirtuína 1/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
4.
J Stroke Cerebrovasc Dis ; 24(11): 2474-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26381781

RESUMO

BACKGROUND: In this study, we evaluated the microembolic signals (MES) frequency with transcranial Doppler ultrasound (TCD) in patients with atrial fibrillation (AF) under anticoagulant therapy, and we compared the treatment groups. METHODS: Ninety-nine patients with nonvalvular AF with a history of stroke using warfarin (46%), 67 patients using rivaroxaban (31%), and 49 patients using dabigatran (23%), that is, a total of 215 patients, who have been referred to the stroke outpatient section of our department from May 2013 to November 2014, were included in the study. CHA(2)DS(2)VASc scoring was made for all patients, and International Normalized Ratio (INR) value was evaluated in patients using warfarin. All patients were monitored with TCD on the middle cerebral arteries bilaterally for 30 minutes. Embolic signals were evaluated according to their density and the mean number of signals in 2 consecutive recordings. RESULTS: The incidence of emboli in the treatment group was 32 (32%) for warfarin, 24 (36%) for rivaroxaban, and 17 (35%) for dabigatran. The analysis of variance revealed that there was no statistically significant differences between the treatment groups in terms of patients' age (P = .145), CHA(2)DS(2)VASc scores (P = .968), and the number of emboli (P = .783). As CHA(2)DS(2)VASc score increases, number of emboli increase. A statistically significant negative correlation between the number of emboli and INR scores was found in the warfarin group. The number of emboli decreases as INR decreases. CONCLUSIONS: As we aim to reduce the risk of emboli to a minimum with anticoagulant therapy, this screening for MES can give us an idea for the risk of stroke.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Embolia/tratamento farmacológico , Resultado do Tratamento , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Dabigatrana , Embolia/diagnóstico por imagem , Embolia/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/patologia , Rivaroxabana , Índice de Gravidade de Doença , Ultrassonografia Doppler Transcraniana , Varfarina
5.
Zhongguo Zhong Yao Za Zhi ; 39(17): 3367-70, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25522630

RESUMO

OBJECTIVE: To establish a general method of focal cerebral ischemia model in different varieties of mice. METHOD: Each group of healthy adult KM and C57BL/6 mice were randomly divided into control group (n = 10) and MCAO group (n = 10). The mice in MCAO group were applied in the preparation of the MCAO model by intraluminal occlusion using monofilament. Twenty-four hours after operation,the neurologic function was evaluated,middle cerebral artery blood flow was monitored and the infarction volume was calculated by TTC staining, to evaluate the reliability of the model. RESULT: In the MCAO group, the base value of the cerebral blood flow down of KM and C57BL/6 mice respectively was (81.65 ± 4.59)%, (83.68 ± 6.25)%. The neurological deficit score respectively was (2.30 ± 0.82), (2.50 ± 0.80). TTC staining can clearly show the infarction area, and relatively stable, 24 hours of the survival rate of KM and C57BL/6 mice were 100% and 80% respectively. CONCLUSION: The key link is the optimization and improvement of monofilament, temperature, anesthesia and so on. The modified intraluminal occlusion of MCAO using monofilament is a kind of reliable and simple method to establish experimental cerebral ischemia model in mice.


Assuntos
Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/fisiopatologia , Artéria Cerebral Média/fisiopatologia , Animais , Velocidade do Fluxo Sanguíneo , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Encéfalo/fisiopatologia , Isquemia Encefálica/complicações , Circulação Cerebrovascular , Infarto da Artéria Cerebral Média/complicações , Masculino , Camundongos Endogâmicos C57BL , Artéria Cerebral Média/patologia , Artéria Cerebral Média/cirurgia , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/fisiopatologia , Especificidade da Espécie
6.
PLoS One ; 9(10): e110766, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25333878

RESUMO

BACKGROUND AND PURPOSE: Chronic hypertension decreases internal diameter of cerebral arteries and arterioles. We recently showed that short-term treatment with the angiotensin II receptor blocker telmisartan restored baseline internal diameter of small cerebral arterioles in spontaneously hypertensive rats (SHR), via reversal of structural remodeling and inhibition of the angiotensin II vasoconstrictor response. As larger arteries also participate in the regulation of cerebral circulation, we evaluated whether similar short-term treatment affects middle cerebral arteries of SHR. METHODS: Baseline internal diameters of pressurised middle cerebral arteries from SHR and their respective controls, Wistar Kyoto rats (WKY) and responses to angiotensin II were studied in a small vessel arteriograph. Pressure myogenic curves and passive internal diameters were measured following EDTA deactivation, and elastic modulus from stress-strain relationships. RESULTS: Active baseline internal diameter was 23% lower in SHR compared to WKY, passive internal diameter (EDTA) 28% lower and elastic modulus unchanged. Pressure myogenic curves were shifted to higher pressure values in SHR. Telmisartan lowered blood pressure but had no effect on baseline internal diameter nor on structural remodeling (passive internal diameter and elastic modulus remained unchanged compared to SHR). Telmisartan shifted the pressure myogenic curve to lower pressure values than SHR. CONCLUSION: In the middle cerebral arteries of SHR, short-term treatment with telmisartan had no effect on structural remodeling and did not restore baseline internal diameter, but allowed myogenic tone to adapt towards lower pressure values.


Assuntos
Anti-Hipertensivos/farmacologia , Remodelamento Atrial/efeitos dos fármacos , Benzimidazóis/farmacologia , Benzoatos/farmacologia , Artérias Cerebrais/efeitos dos fármacos , Artérias Cerebrais/patologia , Animais , Anti-Hipertensivos/administração & dosagem , Benzimidazóis/administração & dosagem , Benzoatos/administração & dosagem , Pressão Sanguínea/efeitos dos fármacos , Artérias Cerebrais/fisiopatologia , Masculino , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/patologia , Artéria Cerebral Média/fisiopatologia , Ratos , Ratos Endogâmicos SHR , Telmisartan , Vasoconstrição/efeitos dos fármacos
7.
Toxicol Mech Methods ; 24(6): 438-47, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24965906

RESUMO

This study was designed to test the pre-treatment doses of guggulipid (50 mg/kg), aspirin (100 mg/kg) per orally and co-administration of both drugs for 28 days followed by middle cerebral artery occlusion - a model of focal cerebral ischemia in rats. Middle cerebral artery was occluded for two hours, followed by reperfusion for 22 hours for the induction of focal cerebral ischemia in rats. Neurobehavioral tests like locomotor activity and grip strength tests were performed before sacrificing the animal. After neurobehavioral tests, the animals were sacrificed for the measurement of infarction areas and biochemical estimations in brain. Locomotor activity and grip strength were significantly improved in guggulipid and aspirin pre-treated rats. Guggulipid and aspirin pre-treatment reduced the infarction areas as compared with middle cerebral occluded (MCAO) rats. An elevation of nitrite, thiobarbituric acid reactive substance (TBARS), acetylcholine esterase activity (AchE) and reduction in antioxidant enzymes like superoxide dismutase (SOD), glutathione (GSH) and catalase were observed following MCAO. Pre-treatment with guggulipid and aspirin caused a reduction in TBARS and nitrite levels, AchE, but elevated GSH level, SOD and catalase activities as compared with MCAO rats. The protective effects observed in this study were due to antioxidant, anti-inflammatory and anti-hyperlipidemic properties of guggulipid. The protective effect of guggulipid in cerebral ischemia, that it may have a role in reversing the symptoms and may offer significant neuroprotection in stroke.


Assuntos
Aspirina/farmacologia , Isquemia Encefálica/prevenção & controle , Artéria Cerebral Média/patologia , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Gomas Vegetais/farmacologia , Acetilcolinesterase/metabolismo , Animais , Aspirina/administração & dosagem , Isquemia Encefálica/patologia , Catalase/metabolismo , Commiphora , Inibidores de Ciclo-Oxigenase/administração & dosagem , Sinergismo Farmacológico , Quimioterapia Combinada , Hipolipemiantes/administração & dosagem , Hipolipemiantes/farmacologia , Masculino , Artéria Cerebral Média/efeitos dos fármacos , Atividade Motora , Fármacos Neuroprotetores/administração & dosagem , Extratos Vegetais/administração & dosagem , Gomas Vegetais/administração & dosagem , Ratos , Ratos Wistar
10.
J Stroke Cerebrovasc Dis ; 22(5): 656-60, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22576008

RESUMO

BACKGROUND: There has been little effective treatment in patients with cerebral infarction at >24 hours after onset. We assessed the effects of high-dose argatroban therapy in delayed administration, and investigated the mechanism based on our clinical findings. METHODS: Argatroban 30 mg was first administered for 15 minutes intravenously, and then 90 mg for 60 minutes followed by 60 mg for 60 minutes were infused continuously. The change of vascular obstruction caused by the treatment was assessed with magnetic resonance angiography. RESULTS: In 4 patients studied, high-dose argatroban resulted in 100% recanalization of occluded vessels (5/5), even though argatroban was administrated >24 hours after onset. On the other hand, when an inadequate dose of argatroban was administered, a hemorrhage was identified. This supports our hypothesis that high-dose argatroban promotes recanalization by deactivating thrombin and exerting an anticoagulant effect on the vascular endothelium. CONCLUSIONS: High-dose argatroban is an effective treatment for cerebral infarction and offers a novel therapeutic approach for delayed hospitalized patients at >24 hours after onset. Additional studies are necessary to identify the cellular and molecular mechanisms and determine the adequate dose in order to reduce risks of complication.


Assuntos
Antitrombinas/administração & dosagem , Infarto da Artéria Cerebral Média/tratamento farmacológico , Artéria Cerebral Média/efeitos dos fármacos , Ácidos Pipecólicos/administração & dosagem , Tempo para o Tratamento , Idoso , Idoso de 80 Anos ou mais , Antitrombinas/efeitos adversos , Arginina/análogos & derivados , Coagulação Sanguínea/efeitos dos fármacos , Constrição Patológica , Esquema de Medicação , Feminino , Humanos , Infarto da Artéria Cerebral Média/sangue , Infarto da Artéria Cerebral Média/diagnóstico , Infusões Intravenosas , Angiografia por Ressonância Magnética , Masculino , Artéria Cerebral Média/patologia , Ácidos Pipecólicos/efeitos adversos , Sulfonamidas , Fatores de Tempo , Resultado do Tratamento
11.
Chin J Integr Med ; 19(2): 137-42, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23001461

RESUMO

OBJECTIVE: To investigate the effects of Qushuanling Capsule ( QSLC) on thrombus formation and platelet aggregation in rats. METHODS: Arteriovenous bypass, venous thrombosis, and middle cerebral artery thrombosis models were used in rats to investigate the anti-thrombotic effects of QSLC, a compound of nine Chinese herbs. The platelet aggregation induced by adenosine diphosphate (ADP), thrombin or arachidonic acid (AA), as well as the contents of thromboxane B(2) (TXB(2)) and 6-keto-prostaglandin F1α (6-keto-PGF1α) in rat plasma and aortic walls, were determined to investigate the possible mechanisms of the anti-thrombotic effects of QSLC. RESULTS: After oral administration with QSLC for 7 days, arteriovenous bypass thrombosis was obviously suppressed compared with the model group, venous thrombosis was also obviously suppressed, rat behaviors were obviously improved, and brain infarct size as well as water content were also reduced. The platelet aggregation induced by ADP or thrombin was inhibited by QSLC, but the drug had no effect on AA-induced platelet aggregation and content of TXB(2) and 6-keto-PGF1α in plasma and the aortic wall. CONCLUSION: These results suggest that QSLC can be used in the prevention and treatment of thrombotic diseases, and that its mechanism of action may be related to inhibition of platelet aggregation.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Agregação Plaquetária/efeitos dos fármacos , Trombose/tratamento farmacológico , Trombose/patologia , 6-Cetoprostaglandina F1 alfa/sangue , Difosfato de Adenosina/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/patologia , Infarto Cerebral/sangue , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/patologia , Masculino , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/patologia , Ratos , Ratos Sprague-Dawley , Tromboxano B2/sangue , Trombose Venosa/tratamento farmacológico , Trombose Venosa/patologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-24082328

RESUMO

We investigated the curative effect of Pheretima aspergillum (earthworm, PA) on rats with middle cerebral artery occlusion (MCAo). The MCAo-induced cerebral infarction was established and its underlying mechanisms by counting the infarction areas and evaluating the rats' neurological status. Immunostaining was used to test the expression of NeuN, and glial fibrillary acidic (GFAP), S100B, and brain-derived neurotrophic factor (BDNF) proteins. Our results showed that oral administration of PA for two weeks to rats with MCAo successfully reduced cerebral infarction areas in the cortex and striatum, and also reduced scores of neurological deficit. The PA-treated MCAo rats showed greatly decreased neuronal death, glial proliferation, and S100B proteins in the penumbra area of the cortex and in the ischemic core area of the cortex, but BDNF did not changed. These results demonstrated novel and detailed cellular mechanisms underlying the neuroprotective effects of PA in MCAo rats.


Assuntos
Produtos Biológicos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Infarto Cerebral/tratamento farmacológico , Infarto da Artéria Cerebral Média/complicações , Fármacos Neuroprotetores/uso terapêutico , Oligoquetos , Administração Oral , Animais , Antígenos Nucleares/metabolismo , Produtos Biológicos/farmacologia , Encéfalo/metabolismo , Encéfalo/patologia , Infarto Cerebral/etiologia , Infarto Cerebral/metabolismo , Infarto Cerebral/patologia , Modelos Animais de Doenças , Masculino , Artéria Cerebral Média/patologia , Proteínas do Tecido Nervoso/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo
13.
Acta Neurochir Suppl ; 111: 225-30, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21725760

RESUMO

Capsaicin, a transient receptor potential vanilloid 1 (TRPV1) agonist, has recently been shown to provide neuroprotection against brain injury in experimental adult models of cerebral ischemia. Accordingly, in this study, we investigated the way in which capsaicin-mediated TRPV1 modulation could attenuate damage in an experimental hypoxic-ischemic (HI) neonatal brain injury model. The Rice-Vannucci method was used in 10-day-old rat pups by performing unilateral carotid artery ligation followed by 2 h of hypoxia (8% O2 at 37°C). Capsaicin was administered intraperitoneally (0.2 mg/kg or 2.0 mg/kg) at 3 h pre-HI or 1 h post-HI. Post assessment included measurement of infarction volume at 24 and 72 h in addition to an assessment of the vascular dynamics of the middle cerebral artery (MCA) at 6 h post-HI. The results indicated that pre-treatment with capsaicin reduced infarction volume significantly with either low-dose or high-dose treatment. Pre-treatment also improved myogenic tone and decreased apoptotic changes in the distal MCA. We concluded that capsaicin pre-treatment may provide neurovascular protection against neonatal HI.


Assuntos
Capsaicina/administração & dosagem , Infarto da Artéria Cerebral Média/prevenção & controle , Artéria Cerebral Média/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Análise de Variância , Animais , Animais Recém-Nascidos , Infarto Encefálico/etiologia , Infarto Encefálico/prevenção & controle , Modelos Animais de Doenças , Esquema de Medicação , Regulação da Expressão Gênica/efeitos dos fármacos , Infarto da Artéria Cerebral Média/patologia , Artéria Cerebral Média/patologia , Fosfopiruvato Hidratase/metabolismo , Ratos , Canais de Cátion TRPV/metabolismo , Sais de Tetrazólio , Fatores de Tempo , Fator de von Willebrand/metabolismo
14.
Exp Brain Res ; 206(2): 209-17, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20369232

RESUMO

Left unilateral neglect is frequently reported after right hemispheric lesions of the middle cerebral artery (MCA) damaging the parietal-frontal cortical-subcortical network subserving space representation and awareness. However, accumulating evidence shows that neglect can also follow lesions of the posterior cerebral artery (PCA) that do not directly affect this parietal-frontal network. Surgical studies in the monkeys have demonstrated that complete callosal resection combined with lesion of the right optic tract entirely deprives the right hemisphere of visual inputs from the left hemispace provoking severe left unilateral neglect. Here, through the detailed study of two patients we show, for the first time, that PCA lesions selectively affecting the splenium of the corpus callosum and the adjacent right primary visual cortex provoke severe neglect selectively restricted to the visual domain. No trace of personal, motor or representational-imagery neglect was found. Also at variance with previous case studies in which neglect followed lesion of the trunk or the genu of the corpus callosum, no restriction of neglect to tasks performed with the right hand, no left hemispatial limb akinesia, no tactile extinction for the left hand and no tactile anomia for stimuli explored with the left hand were observed. These findings demonstrate that brain lesions depriving intact parietal and frontal attentional areas from specific sensory inputs can yield spatial neglect limited to specific sensory modalities or sectors of space.


Assuntos
Atenção/fisiologia , Lesões Encefálicas/complicações , Lateralidade Funcional/fisiologia , Transtornos da Percepção/etiologia , Percepção Espacial/fisiologia , Idoso , Idoso de 80 Anos ou mais , Mapeamento Encefálico , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Feminino , Lobo Frontal/patologia , Humanos , Masculino , Artéria Cerebral Média/patologia , Testes Neuropsicológicos , Lobo Parietal/patologia
15.
J Pharmacol Sci ; 109(3): 368-79, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19305121

RESUMO

The roots of Panax notoginseng (PN) are commonly used as a therapeutic agent to stop hemorrhage and as a tonic to promote health in traditional Korean medicine. Stroke triggers an inflammatory response that not only plays a central role in the pathogenesis of cerebral ischemia, but also induces secondary damage. This study was designed to investigate the neuroprotective effects of the methanol extract of PN on the infarct volume induced by middle cerebral artery occlusion (MCAO) (90-min occlusion and 24-h reperfusion) in rat brains. The PN extract (50 mg/kg, i.p.) was administered 2 h after the onset of MCAO. The PN-treated groups had a reduction in infarct volume by 23.82 +/- 8.9%. In the PN extract-treated groups, the microglial density was significantly decreased in the peri-infarct region; the underlying mechanism was inhibition of inflammatory mediators, such as inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2, via blocking of the NF-kappaB pathway. Furthermore, in vitro studies showed that the PN extract significantly reduced the production of iNOS-derived NO and COX-2-derived prostaglandin E(2) through the regulation of gene transcription levels in primary microglia and BV-2 cells. These results suggest that anti-inflammatory and microglial activation inhibitory effects of the PN extract may contribute to its neuroprotective effects in brain ischemia.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Panax notoginseng/química , Extratos Vegetais/farmacologia , Animais , Isquemia Encefálica/fisiopatologia , Ciclo-Oxigenase 2/efeitos dos fármacos , Dinoprostona/metabolismo , Injeções Intraperitoneais , Masculino , Medicina Tradicional Coreana , Microglia/efeitos dos fármacos , Microglia/metabolismo , Artéria Cerebral Média/patologia , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Óxido Nítrico Sintase Tipo II/efeitos dos fármacos , Óxido Nítrico Sintase Tipo II/metabolismo , Raízes de Plantas , Ratos , Ratos Sprague-Dawley , Transcrição Gênica/efeitos dos fármacos
16.
J Pharm Pharmacol ; 60(3): 349-55, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18284815

RESUMO

Breviscapine, a flavonoid isolated from the traditional Chinese medicinal herb Erigerin breviscapus, has been proved to be effective in protecting the brain against ischaemic damage, but the mechanisms remain unknown. In this study, we have demonstrated the effects of breviscapine on neuronal apoptosis in a rat model of transient focal cerebral ischaemia. Rats were administered with breviscapine (50 or 100 mg kg(-1)/day) intragastrically for seven successive days, then subjected to 2-h brain ischaemia induced by middle cerebral artery occlusion, followed by 24-h reperfusion. After reperfusion, the rats were killed and the brain samples were collected. Haematoxylin-eosin staining was used to evaluate the histopathological changes. Terminal deoxynucleotidyl transferase-mediated biotiny-lated UTP nick end labeling (TUNEL) and flow cytometry (FCM) analysis were used to detect the level of apoptosis. The expressions of bcl-2 and caspase-3 in the cortex were determined by Western blot. Significant increases in the number of haematoxylin-eosin- and TUNEL-positive staining cells and DNA fragmentation were observed at 24 h after reperfusion, and the increases were inhibited by breviscapine (50 and 100 mg kg(-1)). Breviscapine at both doses markedly inhibited the expression and activation of caspase-3 and up-regulated the expression of bcl-2. These findings suggested that breviscapine attenuated neuroapoptosis and regulated the protein expression related to apoptosis after transient focal cerebral ischaemia, which may have contributed, in part, to the protective effects of breviscapine on cerebral ischaemic damage.


Assuntos
Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Ataque Isquêmico Transitório/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Animais , Caspase 3/efeitos dos fármacos , Caspase 3/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Erigeron/química , Flavonoides/administração & dosagem , Citometria de Fluxo , Regulação da Expressão Gênica/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Masculino , Medicina Tradicional Chinesa , Artéria Cerebral Média/patologia , Fármacos Neuroprotetores/administração & dosagem , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley
17.
Eur J Neurol ; 14(8): 937-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17662019

RESUMO

We report the rare presentation of lacunar stroke syndrome secondary to single perforator mouth occlusion from radiation-induced middle cerebral artery (MCA) stem arteriopathy. A 30-year-old female had acute-onset right-sided ataxic hemiparesis and dysarthria. As a child, she had a medulloblastoma of the posterior fossa and had surgery followed by cranial radiotherapy. She had no significant vascular risk factors. Acute CT showed extensive bilateral basal ganglia and left thalamic calcification; DWI showed a left internal capsule lacunar infarct; and MRA and CTA showed a 50% stenosis of the proximal left MCA.


Assuntos
Infarto Encefálico/etiologia , Infarto da Artéria Cerebral Média/etiologia , Artéria Cerebral Média/efeitos da radiação , Radioterapia/efeitos adversos , Adulto , Gânglios da Base/patologia , Gânglios da Base/efeitos da radiação , Infarto Encefálico/patologia , Infarto Encefálico/fisiopatologia , Calcinose/etiologia , Calcinose/patologia , Calcinose/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Cápsula Interna/irrigação sanguínea , Cápsula Interna/patologia , Cápsula Interna/fisiopatologia , Meduloblastoma/radioterapia , Artéria Cerebral Média/patologia , Artéria Cerebral Média/fisiopatologia , Tálamo/patologia , Tálamo/efeitos da radiação , Tomografia Computadorizada por Raios X
18.
Exp Toxicol Pathol ; 59(1): 9-16, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17596924

RESUMO

A monkey model (Cynomolgus) was established to evaluate the delayed neurological damage evident at areas distant from ischemic cerebral foci. In addition to proton magnetic resonance spectroscopy (MRS) monitoring in life, histological examinations of specimens of the brain was conducted on lesions produced 6h and 1, 2, 4 and 8 weeks after unilateral (left) permanent middle cerebral artery occlusion (pMCO) on five monkeys. In addition to the typical images evident at primary ischemic foci around the middle cerebral artery, MRS revealed and enhanced, clearer region, due to edema extending into the reticular and compact area of the left substantia nigra one week after pMCO, inducing right hemiparesis caused by focal cerebral ischemia. Similar histological lesions were also induced in the left thalamus 4 weeks after pMCO. Thereafter, a variety of histological findings including astrocytic activation, reduced number of nerve cells and gliosis were found in the above described areas far apart from the original ischemic cerebral foci. Our monkey model should be suitable for studies elucidating the pathological process in cerebral ischemia as well as for investigating therapeutic strategies involving ischemic stroke in humans.


Assuntos
Arteriopatias Oclusivas/patologia , Isquemia Encefálica/patologia , Modelos Animais de Doenças , Espectroscopia de Ressonância Magnética/métodos , Artéria Cerebral Média/patologia , Animais , Arteriopatias Oclusivas/complicações , Astrócitos/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/etiologia , Isquemia Encefálica/metabolismo , Gliose/complicações , Gliose/metabolismo , Gliose/patologia , Macaca fascicularis , Imageamento por Ressonância Magnética , Neurônios/patologia , Paresia/etiologia , Paresia/metabolismo , Paresia/fisiopatologia , Tálamo/patologia
19.
Prog Neurol Surg ; 20: 375-387, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17318004

RESUMO

In vitro isometric myograph and histopathological studies were performed on rat middle cerebral arteries (MCAs) to explore changes in contractile capacity following experimental Gamma Knife radiosurgery. Right MCAs were treated with 25 Gy and 50 Gy at the 50% isodose line, while contralateral vessels received 15 Gy and 20 Gy at the 20% isodose region. Survival period varied from 3 to 18 months. Reduction in contractile capacity of irradiated normal rat MCAs was detected but their lumina remained patent. In another study, we investigated human AVM tissue cultures in order to detect genetic and phenotypic modifications contributing to vessel occlusion after irradiation. In culture, the proliferation index decreased considerably following 15-, 20-, 25- or 50-Gy irradiation at the 5th posttreatment day and remained depressed during the observation period of 14 days. P53, p21Waf-1 and mdm-2 mRNA contents were elevated significantly after irradiation, indicating enhanced apoptosis. Immunohistochemistry revealed vigorous vimentin positivity in the nonirradiated control AVM cultures, which gradually decreased by the time in the irradiated specimens. Smooth muscle alpha-actin positivity was prominent in the irradiated cultivated samples, suggesting transformation of resting fibroblasts onto activated myofibroblastic elements with contractile capacity. This transformation process was confirmed by the appearance of TGF-Beta in the irradiated AVM cell lines also. These data support the hypothesis that one of the contributing factors to AVM shrinkage and obliteration after radiosurgery might be fibrocyte-myofibroblastic cell transformation in the vessel wall.


Assuntos
Malformações Arteriovenosas Intracranianas/patologia , Malformações Arteriovenosas Intracranianas/fisiopatologia , Malformações Arteriovenosas Intracranianas/cirurgia , Artéria Cerebral Média/patologia , Artéria Cerebral Média/fisiologia , Animais , Humanos , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/efeitos da radiação , Modelos Animais , Necrose , Cloreto de Potássio/farmacologia , Prostaglandinas F/farmacologia , Radiocirurgia/métodos , Ratos , Ratos Wistar , Técnicas de Cultura de Tecidos , Uridina Trifosfato/farmacologia
20.
Neurosurg Focus ; 21(3): E4, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-17029343

RESUMO

OBJECT: The efficacy of nimodipine was examined in a murine model of subarachnoid hemorrhage (SAH). End points included the diameter of the lumen of the middle cerebral artery (MCA) and behavioral outcome. An apolipoprotein E (apoE)-mimetic peptide, acetyl-AS-Aib-LRKL-Aib-KRLL-amide, previously shown to have promise in this model was tested both alone and in combination with nimodipine. The effects of carboxyamidotriazole (CAI), a non-voltage-gated calcium channel blocker, were explored using the same animal paradigm. METHODS: Experimental SAH was induced in male C57B1/6J mice. For 3 days postoperatively, behavioral analyses were performed. In the first experiment, the mice were treated with vehicle or with low- or high-dose CAI for 3 days. In the second experiment, the mice were treated with vehicle, high- and low-dose nimodipine, and/or the apoE-mimetic peptide. On postoperative Day 3 each mouse was killed and perfused. Following this, the right MCA was removed and its lumen measured. Mice that received nimodipine demonstrated significant behavioral improvements when compared with vehicle-treated mice, but there was no clear dose-dependent effect on MCA diameter. Administration of the apoE-mimetic peptide was associated with improved functional performance and a significant reduction in vasospasm. Mice that received high-dose CAI performed worse on functional tests, despite a significant increase in the diameters of their MCA lumina. CONCLUSIONS: These results demonstrate a dissociation between vasospasm and neurological outcomes that is consistent with findings of previous clinical trials.


Assuntos
Anti-Hipertensivos/uso terapêutico , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/patologia , Vasoespasmo Intracraniano/tratamento farmacológico , Vasoespasmo Intracraniano/patologia , Animais , Apolipoproteínas E/química , Comportamento Animal , Bloqueadores dos Canais de Cálcio/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/patologia , Exame Neurológico , Nimodipina/uso terapêutico , Peptídeos/uso terapêutico , Tempo de Reação/efeitos dos fármacos , Teste de Desempenho do Rota-Rod/métodos , Hemorragia Subaracnóidea/complicações , Resultado do Tratamento , Triazóis/uso terapêutico , Vasoespasmo Intracraniano/etiologia
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