Applicability of [18F]FDG/PET for investigating rosmarinic acid preconditioning efficacy in a global stroke model in mice

ABSTRACT Positron emission tomography (PET) is a non-invasive nuclear imaging technique that uses radiotracers to track cell activity. The radiopharmaceutical 18F-fluoro-2-deoxyglucose ([18F] FDG) is most commonly used in nuclear medicine for the diagnosis of various diseases, including stroke. A stroke is a serious condition with high mortality and morbidity rates. Rosmarinic acid (RA) is a promising therapeutic agent that exerts neuroprotective effects against various neurological diseases. Therefore, this study aimed to evaluate the applicability of [18F]FDG/PET for investigating the neuroprotective effects of RA in case of a global stroke model in mice. The [18F]FDG/PET technique facilitates the observation of ischemia and reperfusion injuries in the brain. Moreover, the recovery of glucose metabolism in three specific brain regions, the striatum, superior colliculus, and inferior colliculus, was observed after preconditioning with RA. It was concluded that the [18F]FDG/PET technique may be useful for stroke diagnosis and the assessment of treatment response. In addition, a long-term longitudinal study using biochemical analysis in conjunction with functional imaging may provide further conclusive results regarding the effect of RA on cerebral ischemia.

Therapeutic Effects of Dimethyl Fumarate on the Rat Model of Brain Ischemia

Abstract Blood-brain barrier (BBB) disruption, inflammation, and cell death are major pathogenic mechanisms in ischemic stroke. Dimethyl fumarate (DMF) has anti-inflammatory and immune-modulatory effects. So, this study aimed to elucidate the effects of DMF on brain ischemia in the middle cerebral artery occlusion (MCAO) model. 69 Sprague-Dawley male rats were allocated into a sham group that was just subjected to surgery stress; vehicle and DMF groups, after MCAO, received vehicle or 30 mg/kg DMF for three days. Neurological scores were evaluated every day. BBB disruption was evaluated by the extravasation of Evans blue. In addition to the measurement of brain water content, the total and infarct volume, numerical density, and the total number of neurons, non-neurons, and dead neurons in the right cortex were estimated by stereological methods. RT-PCR was done to analyze the expression levels of NF-κB and Nrf2. Although brain ischemia treatment with DMF did not have a significant effect on the infarction size, it improved neurobehavioral function, BBB disruption, cerebral edema, increased number of neurons, and expression of Nrf2. It also decreased the number of dead neurons and the expression of NF-κB. DMF beneficial effects on stroke may be mediated through both increase of the Nrf2 and decrease of NF-κB expression

18ß-glycyrrhetinic acid attenuates global cerebral ischemia/reperfusion-induced cardiac damage in C57BL/J6 mice

Abstract The aim of the present study is to investigate the cardioprotective effects of 18ß-glycyrrhetinic acid (18ß -GA) against oxidative and histological damage caused by global cerebral ischemia/ reperfusion (I/R) in C57BL/J6 mice. All male mice (n:40) were randomly divided into four groups: (1) sham-operated (Sham), (2) I/R, (3) 18ß-GA, and (4) 18ß -GA+I/R. Ischemia was not applied to the sham and 18ß-GA groups. In the I/R group, the bilateral carotid arteries were clipped for 15 min to induce ischemia, and the mice were treated with the vehicle for 10 days. In the 18ß-GA group, the mice were given 18ß-GA (100 mg/kg) for 10 days following a median incision without carotid occlusion. In the 18ß-GA+I/R group, the ischemic procedure performed to the I/R model was applied to the animals and afterwards they were intraperitoneally (i.p.) treated with 18ß-GA (100 mg/kg) for 10 days. It was found that global cerebral I/R increased TBARS levels and decreased antioxidant parameters. The 18ß-GA treatment decreased the level of TBARS and increased GSH, GPx, CAT, SOD activities. Also, the control group cardiac tissue samples were observed to have a normal histological appearance with the Hematoxylin-Eosin staining method. Histopathological damage was observed in the heart tissue samples belonging to the I/R group. The 18ß-GA treatment ameliorates oxidative and histological injury in the heart tissue after global ischemia reperfusion, and may be a beneficial alternative treatment

Morphometric analysis and pattern of protein and gene expression of apoptosis in focal cerebral ischemia in rats and the neuroprotetive action of hypothermia and ketoprofen / Análisis morfométrico y modelo de expresión de proteína y genes de apoptosis en isquemia cerebral focal en ratas y la acción neuroprotectora de hipotermia y ketoprofeno

This study aimed to investigate the morphometric and the pattern of protein and gene expression related to the extrinsic apoptotic pathway in experimental focal cerebral ischemia and the hole of neuroprotection with hypothermia and ketoprofen. For this analysis, 120 rats were randomly divided into 3 groups (20 animals each): control - no surgery (20 animals); sham - simulation of surgery (20 animals); ischemic - focal ischemia for 1 hour, without reperfusion (80 animals) and divided into four subgroups with 20 animals each: ischemic + intraischemic hypothermia; ischemic + previous intravenous ketoprofen, and ischemic + hypothermia and ketoprofen. The infarct volume was measured using morphometric analysis of infarct areas defined by triphenyl tetrazolium chloride and the patterns of expression of the apoptosis genes (Fas, c-Flip, caspase-8 and caspase-3) and the apoptosis protein caspase-3 were evaluated by quantitative real-time PCR and immunohistochemistry, respectively. Hypo expression of genes of extrinsic pathway of apoptosis was observed: Fas receptor, c-Flip and caspase-8 in the ischemics areas. Increases in the gene and protein caspase-3 in the ischemic areas were also observed, and these increases were reduced by hypothermia and ketoprofen, also noted in the morphometric study. The caspases-3 increase suggests that this gene plays an important role in apoptosis, probably culminating in cell death and that the neuroprotective effect of hypothermia and ketoprofen is involved.

Este estudio tuvo como objetivo investigar la morfometría y el patrón de expresión de proteínas y genes relacionados con la vía apoptótica extrínseca en la isquemia cerebral focal experimental y el agujero de neuroprotección con hipotermia y ketoprofeno. Se dividieron aleatoriamente 120 ratas en 3 grupos (20 animales cada uno): control - sin cirugía (20 animales); simulación - simulación de cirugía (20 animales); isquemia isquemia focal durante 1 hora, sin reperfusión (80 animales) y dividida en cuatro subgrupos con 20 animales cada uno: isquemia + hipotermia intraisquémica; isquemia + ketoprofeno intravenoso previo, e isquemia + hipotermia y ketoprofeno. El volumen del infarto se midió utilizando un análisis morfométrico de áreas de infarto definidas por cloruro de trifenil tetrazolio y los patrones de expresión de los genes de apoptosis (Fas, c-Flip, caspase-8 y caspase-3) y la proteína de apoptosis caspase-3 fueron evaluados por PCR cuantitativa en tiempo real e inmunohistoquímica, respectivamente. Se observó hipoexpresión de genes de la vía extrínseca de la apoptosis: receptor Fas, c-Flip y caspasa-8 en las áreas isquémicas. También se observaron aumentos en el gen y la proteína caspasa-3 en las áreas isquémicas y estos aumentos se redujeron por hipotermia y ketoprofeno, también observado por estudio morfométrico. El aumento de caspasas-3 sugiere que este gen tiene un papel importante en la apoptosis, y probable causa de muerte celular, involucrando el efecto neuroprotector de la hipotermia y el ketoprofeno.

Áreas exofocales de lesión a mediano y largo término post-isquemia cerebral / Exofocal areas of medium- and long-term injury after cerebral ischemia

La isquemia cerebral es el tipo de accidente cerebrovascular más común, generando altas tasas de mortalidad y morbilidad a nivel mundial. El entendimiento de la fisiopatología de la lesión cerebral ha requerido de la implementación de modelos experimentales que permitan evaluar los fenómenos celulares, sobre todo aquellos a largo plazo. Por tal razón, el objetivo del presente trabajo fue evaluar las áreas exofocales a un mes y cuatro meses post-isquemia cerebral en un modelo experimental. Ratas Wistar fueron sometidas a una isquemia focal transitoria (t-MCAo) y un grupo fueron sacrificados al mes y otro grupo a los cuatro meses post-isquemia para su posterior análisis histológico. Los cortes fueron teñidos con Nissl y se realizó inmunohistoquímica de la proteína Tau. Nuestros resultados muestran tres áreas de lesión exofocal tanto al mes como a los cuatro meses post-isquemia: el giro dentado, la amígdala y el tálamo. Estas regiones se han asociado al control emocional, lo cual sugiere que a largo término post-isquemia se tengan en cuenta hallazgos clínicos que evalúen cambios emocionales en los pacientes que han sufrido un evento isquémico cerebral.

Cerebral ischemia is the most common type of stroke, which generates high mortality and morbidity rates worldwide. The understanding of the pathophysiology of brain injury has required the implementation of experimental models that allow the evaluation of cellular phenomena, especially those in the long-term. For this reason, the objective of the present work was to evaluate the exofocal areas at one month and four months after cerebral ischemia. Wistar rats were subjected to transient focal ischemia (t-MCAo) and one group was sacrificed one month and another group at four months' post-ischemia for subsequent histological analysis. The cuts were stained with Nissl and immunohistochemistry of the Tau protein was performed. Our results show three areas of exofocal lesion both one month and four months' post-ischemia: the thalamus, the dentate gyrus, and the amygdala. These regions have been associated with emotional control, which suggests that in the long-term post-ischemia clinical findings that evaluate emotional changes in patients who have suffered a cerebral ischemic event should be considered.

Analysis of Caspase-9 protein and microRNAs miR-21, miR-126 and miR-155 related to the apoptosis mechanism in the cerebellum of rats submitted to focal cerebral ischemia associated with an alcoholism model / Análise da proteína Caspase-9 e dos microRNAs miR-21, miR-126 e miR-155 relacionados ao mecanismo de apoptose no cerebelo de ratos submetidos à isquemia cerebral focal associada ao modelo de alcoolismo

ABSTRACT This study aimed to analyze the cerebellum of rats submitted to an experimental focal cerebral ischemia, by middle cerebral artery occlusion for 90 minutes, followed by reperfusion for 48 hours, associated with an alcoholism model. Methods Fifty adult Wistar rats were used, subdivided into five experimental groups: control group (C): animals submitted to anesthesia only; sham group (S): animals submitted to complete simulation of the surgical procedure; ischemic group (I): animals submitted to focal cerebral ischemia for 90 minutes followed by reperfusion for 48 hours; alcoholic group (A): animals that received daily absolute ethanol diluted 20% in water for four weeks; and, ischemic and alcoholic group (I + A): animals receiving the same treatment as group A and, after four weeks, submitted to focal cerebral ischemia for 90 minutes, followed by reperfusion for 48 hours. The cerebellum samples were collected and immunohistochemical analysis of Caspase-9 protein and serum analysis by RT-PCR of microRNAs miR-21, miR-126 and miR155 were performed. Results The expression of Caspase-9 was higher in groups I, A and I + A. In the microRNAs analyses, miR-126 was higher in groups A and I + A, miR-155 was higher in groups I and I + A. Conclusions We conclude that apoptosis occurs in the cerebellar cortex, even if it is distant from the ischemic focus, and that microRNAs 126 and 155 show a correlation with cellular apoptosis in ischemic rats and those submitted to the chronic alcohol model.

RESUMO O objetivo deste estudo foi analisar o cerebelo de ratos submetidos à isquemia cerebral focal experimental, por oclusão da artéria cerebral média por 90 minutos, seguida de reperfusão por 48 horas, associada a um modelo de alcoolismo. Métodos Foram utilizados 50 ratos Wistar adultos, subdivididos em cinco grupos experimentais: grupo controle (C): animais submetidos apenas à anestesia; grupo sham (S): animais submetidos à simulação completa do procedimento cirúrgico; grupo isquêmico (I): animais submetidos à isquemia cerebral focal por 90 minutos, seguidos de reperfusão por 48 horas; grupo alcoólico (A): animais que receberam etanol absoluto diário diluído em 20% em água por quatro semanas; e grupo isquêmico e alcoólico (I + A): animais que recebem o mesmo tratamento do grupo A e, após quatro semanas, submetidos à isquemia cerebral focal por 90 minutos, seguidos de reperfusão por 48 horas. As amostras de cerebelo foram coletadas e a análise imuno-histoquímica da proteína Caspase-9 e a análise sérica por RT-PCR dos microRNAs miR-21, miR-126 e miR155 foram realizadas. Resultados A expressão de Caspase-9 foi maior nos grupos I, A e I + A. Nas análises de microRNAs, o miR-126 foi maior nos grupos A e I + A, o miR-155 foi maior nos grupos I e I + A. Conclusões Concluímos que a apoptose ocorre no córtex cerebelar, mesmo distante do foco isquêmico, e que os microRNAs 126 e 155 mostram uma correlação com a apoptose celular em ratos isquêmicos e submetidos ao modelo crônico de álcool.

Ceguera cortical como manifestación inicial de endocarditis trombótica no bacteriana / Cortical blindness as initial manifestation of nonbacterial thrombotic endocarditis

La endocarditis trombótica no bacteriana, antiguamente conocida como endocarditis marántica, es una entidad infrecuente en la que se desarrollan vegetaciones estériles, compuestas por fibrina en las válvulas del corazón. Suele diagnosticarse en el momento de la autopsia o en enfermedades oncológicas avanzadas. Las neoplasias malignas más frecuentemente asociadas con esta entidad son las de pulmón, páncreas, estómago y adenocarcinomas de origen primario desconocido. Es necesario descartar la endocarditis infecciosa y establecer la presencia de vegetaciones valvulares mediante ecocardiografía. Presentamos el caso de una paciente con diagnóstico reciente de adenocarcinoma de estómago en estadio avanzado que presentó ceguera cortical e imágenes compatibles con isquemia cerebral. El ecocardiograma transesofágico mostró dos vegetaciones en válvula mitral. Los hemocultivos fueron negativos. Se enfatiza la importancia de sospechar endocarditis trombótica no bacteriana en enfermos con cáncer y embolismo sistémico.

Nonbacterial thrombotic endocarditis, formerly known as marantic endocarditis, it is an infrequent entity in which sterile, fibrin vegetations develop on heart valve leaflets. It is often diagnosed at the time of autopsy or in late-stage malignancies. The most common malignancies associated with nonbacterial thrombotic endocarditis are lung, pancreatic, gastric cancer and adenocarcinomas of an unknown primary site. Diagnosis requires ruling out infective endocarditis and establishing the presence of valvular vegetations using echocardiography. We report the case of a patient with a recent diagnosis of advanced gastric adenocarcinoma who presented with cortical blindness. The computed tomography was compatible with cerebral ischemia. The transoesophageal echocardiogram showed two vegetations in mitral valve. Blood cultures were negative. We emphasize the importance of suspecting nonbacterial thrombotic endocarditis in patients with cancer and systemic embolism.

Arteritis de células gigantes en el sistema vertebrobasilar, isquemias cerebelo-occipitales y parálisis III par: caso clínico / Giant cell arteritis of the vertebrobasilar system, posterior ischemia and palsy of the third nerve: report of one case

Giant cell arteritis is the most common vasculitis in patients aged over 50 years. We report an 89-year-old woman with significant weight loss and persistent frontal-occipital headaches lasting two months. The neurological examination at admission identified a decrease in visual acuity of the left eye, paralysis of the third cranial nerve of the right eye and alterations of body motility without objective signs of damage of the motor or sensitive pathways. Magnetic resonance imaging showed changes of the temporal artery wall and in both vertebral arteries, as well as bilateral cerebellar and occipital ischemic lesions. The Doppler ultrasound of the temporal arteries was compatible with Giant cell arteritis. Treatment with steroids was started. While receiving oral prednisone, the patient suffered new infarcts of the posterior territory, documented with a CAT scan.

Neurogenesis and gliogenesis modulation in cerebral ischemia by CDK5 RNAi-based therapy / Modulación de la neurogénesis y la gliogénesis en la isquemia cerebral mediante una terapia basada en la interferencia de CDK5

Abstract Introduction: Cerebral ischemia is the third cause of death risk in Colombia and the first cause of physical disability worldwide. Different studies on the silencing of the cyclin-dependent kinase 5 (CDK5) have shown that reducing its activity is beneficial in ischemic contexts. However, its effect on neural cell production after cerebral ischemia has not been well studied yet. Objective: To evaluate CDK5 silencing on the production of neurons and astrocytes after a focal cerebral ischemia in rats. Materials and methods: We used 40 eight-week-old male Wistar rats. Both sham and ischemia groups were transduced at CA1 hippocampal region with an adeno-associated viral vector using a noninterfering (shSCRmiR) and an interfering sequence for CDK5 (shCDK5miR). We injected 50 mg/kg of bromodeoxyuridine intraperitoneally from hour 24 to day 7 post-ischemia. We assessed the neurological abilities during the next 15 days and we measured the immunoreactivity of bromodeoxyuridine (BrdU), doublecortin (DCX), NeuN, and glial fibrillary acid protein (GFAP) from day 15 to day 30 post-ischemia. Results: Our findings showed that CDK5miR-treated ischemic animals improved their neurological score and presented increased BrdU+ cells 15 days after ischemia, which correlated with higher DCX and lower GFAP fluorescence intensities, and, although mature neurons populations did not change, GFAP immunoreactivity was still significantly reduced at 30 days post-ischemia in comparison with untreated ischemic groups. Conclusion: CDK5miR therapy generated the neurological recovery of ischemic rats associated with the induction of immature neurons proliferation and the reduction of GFAP reactivity at short and longterm post-ischemia.

Resumen Introducción. La isquemia cerebral es la tercera causa de riesgo de muerte en Colombia y la primera causa de discapacidad física en el mundo. En diversos estudios en los que se silenció la cinasa 5 dependiente de la ciclina (CDK5) se ha demostrado que la reducción de su actividad es beneficiosa frente a la isquemia. Sin embargo, su efecto sobre la neurogénesis después de la isquemia no se ha dilucidado suficientemente. Objetivo. Evaluar el silenciamiento de la CDK5 en la neurogénesis y la gliogénesis después de la isquemia cerebral focal en ratas. Materiales y métodos. Se usaron 40 machos de rata Wistar de ocho semanas de edad. Los grupos de control y los isquémicos sometidos a transducción en la región del hipocampo CA1, se inyectaron intraperitonealmente por estereotaxia con 50 mg/kg de bromodesoxiuridina (BrdU) a partir de las 24 horas y hasta el día 7 después de la isquemia, con un vector viral asociado a adenovirus usando una secuencia no interferente (SCRmiR) y una interferente (CDK5miR). Se evaluó la capacidad neurológica durante los quince días siguientes y se detectó la capacidad de inmunorreacción para la BrdU, la proteína doblecortina (DCX), los núcleos neuronales (NeuN), y la proteína fibrilar acídica de la glía (Glial Fibrillary Acidic Protein, GFAP) a los 15 y 30 días de la isquemia. Resultados. Los animales isquémicos tratados con CDK5miR mejoraron su puntuación neurológica y presentaron un incremento de la BrdU+ a los 15 días de la isquemia, lo cual se correlacionó con una mayor intensidad de la DCX+ y una menor de la GFAP+. No hubo modificación de los NeuN+, pero sí una reducción significativa de la GFAP+ a los 30 días de la isquemia en los animales tratados comparados con los animales isquémicos no tratados. Conclusión. La terapia con CDK5miR generó la recuperación neurológica de ratas isquémicas asociada con la inducción de la neurogénesis y el control de la capacidad de reacción de la proteína GFAP a corto y largo plazo después de la isquemia.

Paraoxonase-1 polymorphisms and cerebral ischemic stroke: a pilot study in mexican patients / Caracterización polimórfica de la paraoxonasa-1 en el infarto cerebral aterotrombótico de una poblacion mexicana: estudio piloto

Abstract Background: The serum paraoxonase-1 (PON1) associated to HDL presents two common polymorphisms in the positions 192 and 55. These polymorphisms are considered determinant of the capacity of HDL to protect LDL from their oxidative modification. In this context, the PON1 genotype has been associated with cardiovascular diseases, including stroke. Objective: To determine the allelic and genotypic frequencies of PON1 L55M and Q192R as well as the enzymatic activities of PON1 in subjects with and without atherothrombotic stroke. Methods: There were included 28 people with atherothrombotic stroke and 29 without stroke. The genotyping was carried out by PCR-RFLP and the phenotyping by measurement of the activities of paraoxonase and arylesterase in serum. Results: For the polymorphism Q192R, the allelic frequencies (Q/R) were 0.46/0.54 and 0.48/0.52 (p= 0.843) for the control group and the group with stroke, respectively. While for the polymorphism L55M, the allelic frequencies (L/M) were 0.81/0.19 for the control group, and 0.78/0.22 for the group with stroke (p= 0.610). The activity levels of paraoxonase were not significantly different between the control and stroke groups (450 vs. 348 UI/mL, p= 0.093) While the activity levels of arylesterase were significantly different between the studied groups (90 vs. 70 UI/mL, p= 0.001); however, upon adjustment by multiple linear regression, it was not longer significant. Conclusion: The polymorphisms Q192R and L55M, and the paraoxonase activity of PON1 are not risk factors for atherothrombotic stroke according to the results of this study.

Resumen Introducción: La paraoxonasa-1 (PON1) sérica asociada a las HDL presenta dos polimorfismos comunes en las posiciones 192 y 55. Estos polimorfismos se consideran determinantes para la capacidad de las HDL de proteger a las LDL de su modificación oxidativa. En este contexto, el genotipo de PON1 se ha asociado con enfermedades cerebrovasculares, que incluyen el infarto cerebral. Objetivo: Determinar las frecuencias alélicas y genotípicas de PON1-L55M y PON1- Q192R, así como las actividades enzimáticas de PON1 en sujetos con y sin infarto cerebral aterotrombótico. Métodos: Se incluyeron 28 personas con infarto cerebral aterotrombótico y 29 sin infarto. Las genotipificaciones se realizaron mediante PCR-RFLP y las fenotipificaciones mediante la medición de las actividades paraoxonasa y arilesterasa en suero. Resultados: Para el polimorfismo Q192R, las frecuencias alélicas (Q/R) fueron 0.46/0.54 y 0.48/0.52 (p= 0.843) para el grupo control y el grupo con infarto, respectivamente. Mientras que para el polimorfismo L55M, las frecuencias alélicas (L/M) fueron 0.81/0.19 para el grupo control y 0.78/0.22 para el grupo con infarto (p= 0.610). Los niveles de actividad paraoxonasa no fueron significativamente diferentes entre los grupos control y con infarto (450 vs. 348 Ul/mL, p= 0.093). Mientras que los niveles de actividad arilesterasa fueron significativamente diferentes entre los grupos estudiados (90 vs. 70 Ul/mL, p= 0.001), sin embargo, al ajustarla por regresión lineal múltiple, dejo de ser significativa. Conclusión: Los polimorfismos Q192R y L55M, y la actividad paraoxonasa de la PON1 no son factores de riesgo para el infarto cerebral aterotrombótico en este estudio.

Could infarct location predict the long-term functional outcome in childhood arterial ischemic stroke? / ¿Puede la localización del infarto predecir el resultado funcional a largo plazo en el ictus isquémico arterial pediátrico?

ABSTRACT Objective: To explore the influence of infarct location on long-term functional outcome following a first-ever arterial ischemic stroke (AIS) in non-neonate children. Method: The MRIs of 39 children with AIS (median age 5.38 years; 36% girls; mean follow-up time 5.87 years) were prospectively evaluated. Infarct location was classified as the absence or presence of subcortical involvement. Functional outcome was measured using the modified Rankin scale (mRS) for children after the follow-up assessment. We utilized multivariate logistic regression models to estimate the odds ratios (ORs) for the outcome while adjusting for age, sex, infarct size and middle cerebral artery territory involvement (significance < 0.05). Results: Both infarcts ≥ 4% of total brain volume (OR 9.92; CI 1.76 - 55.9; p 0.009) and the presence of subcortical involvement (OR 8.36; CI 1.76 - 53.6; p 0.025) independently increased the risk of marked functional impairment (mRS 3 to 5). Conclusion: Infarct extension and location can help predict the extent of disability after childhood AIS.

RESUMEN Objetivo: Para explorar la influencia de la localización del infarto sobre los resultados funcionales a largo plazo después de un primer ictus isquémico arterial (IIA) en ninos posterior a la edad neonatal. Métodos: Se evaluaron de forma prospectiva imágenes por RM de 39 ninos con IIA (mediana de edad: 5,38 años; 36% ninas; seguimiento promedio: 5,87 anos). La localización del infarto fue clasificada como ausencia o presencia de compromiso subcortical. El resultado funcional fue medido utilizando la escala modificada de Rankin (mRS) para ninos en una evaluación al final del seguimiento. Utilizamos modelos de regresión logística multivariada para estimar los odds ratios (ORs) para el resultado ajustado para la edad, sexo, tamaño del infarto y compromiso del territorio vascular de la arteria cerebral media (significancia < 0,05). Resultados: Tanto el tamaño del infarto > 4% del volumen encefálico total (OR 9,92; IC 1,76-55,9; p 0,009) como la presencia de compromiso subcortical (OR 8,36; IC 1,76-53,6; p 0,025) incrementaron independientemente el riesgo de presentar marcado compromiso funcional (mRS 3 a 5). Conclusión: La extensión y localización del infarto pueden ayudar a predecir la magnitud de la discapacidad posterior a un IIA durante la niñez.

Histopathologic comparison of dexmedetomidine's and thiopental's cerebral protective effects on focal cerebral ischemia in rats / Comparação histopatológica dos efeitos protetores cerebrais de dexmedetomidina e tiopental sobre isquemia cerebral focal em ratos

Abstract This study was designed to investigate whether dexmedetomidine and thiopental have cerebral protective effects after focal cerebral ischemia in rats. Thirty male Sprague Dawley rats were randomly assigned to three groups: control group (Group C, n = 10), dexmedetomidine group (Group D, n = 10), thiopental group (Group T, n = 10). After all rats were anesthetized, they were intubated, then mechanically ventilated. A catheter was inserted into the right femoral artery for continuous mean arterial pressure, physiological parameters and blood sampling at baseline, 5 min after occlusion and 20 min after reperfusion. A catheter was inserted into the left femoral vein for intravenous (IV) medication administration. Right common carotid artery of each rat was isolated and clamped for 45 min. At the end of the duration common carotid artery were unclamped and the brain reperfusion was achieved for 90 min. Dexmedetomidine was administered for Group D IV infusion, and Group T received thiopental IV. According to histopathologic scores cerebral ischemia was documented in all rats in Group C, but no ischemia was found in three rats in Group T and in four rats in Group D. Grade 3 cerebral ischemia was documented in three rats in Group C, and in only one rat in both groups T and D. For histopathologic grades the difference between Group T and Group D was not significant (p > 0.05). But the differences between Group C and Group T (p < 0.05) and Group C and Group D (p < 0.01) were statically significant. In conclusion, we demonstrated that dexmedetomidine and thiopental have experimental histopathologic cerebral protective effects on experimental focal cerebral ischemia in rats.

Resumo Este estudo foi desenhado para investigar se dexmedetomidina e tiopental têm efeitos protetores cerebrais após isquemia cerebral focal em ratos. Trinta ratos da linhagem Sprague Dawley foram randomicamente alocados em três grupos: controle (Grupo C, n = 10), dexmedetomidina (Grupo D, n = 10) e tiopental (Grupo T, n = 10). Após a anestesia, foram intubados e ventilados mecanicamente. Um cateter foi inserido na artéria femoral direita para monitoração contínua da pressão arterial média (PAM) e dos parâmetros fisiológicos e para coleta de amostras de sangue na fase basal, 5 minutos após a oclusão e 20 minutos após a reperfusão. Um cateter foi inserido na veia femoral esquerda para administração intravenosa (IV) de medicamentos. A artéria carótida comum direita de cada rato foi isolada e pinçada durante 45 minutos. No fim dos 45 minutos, o pinçamento foi removido e a reperfusão do cérebro foi obtida por 90 minutos. Dexmedetomidina foi administrada por infusão IV no Grupo D e tiopental no Grupo T. De acordo com as pontuações histopatológicas, isquemia cerebral foi observada em todos os ratos do Grupo C, mas não foi encontrada em três ratos do Grupo T e em quatro ratos do Grupo D. O grau 3 de isquemia cerebral foi encontrada em três ratos do grupo C e em apenas um rato de ambos os grupos T e D. Para os graus histopatológicos, a diferença entre o Grupo T e o Grupo D não foi significativa (p > 0,05). Porém, as diferenças entre o Grupo C e o Grupo T (p < 0,05) e entre o Grupo C e o Grupo D (p < 0,01) foram estatisticamente significativas. Em conclusão, demonstramos que dexmedetomidina e tiopental têm efeitos histopatológicos protetores cerebrais sobre isquemia cerebral focal experimental em ratos.

Isoflurane provides neuroprotection in neonatal hypoxic ischemic brain injury by suppressing apoptosis / Isoflurano fornece neuroproteção em lesão cerebral hipóxico-isquêmica neonatal por inibição da apoptose

Abstract Background and objectives: Isoflurane is halogenated volatile ether used for inhalational anesthesia. It is widely used in clinics as an inhalational anesthetic. Neonatal hypoxic ischemia injury ensues in the immature brain that results in delayed cell death via excitotoxicity and oxidative stress. Isoflurane has shown neuroprotective properties that make a beneficial basis of using isoflurane in both cell culture and animal models, including various models of brain injury. We aimed to determine the neuroprotective effect of isoflurane on hypoxic brain injury and elucidated the underlying mechanism. Methods: A hippocampal slice, in artificial cerebrospinal fluid with glucose and oxygen deprivation, was used as an in vitro model for brain hypoxia. The orthodromic population spike and hypoxic injury potential were recorded in the CA1 and CA3 regions. Amino acid neurotransmitters concentration in perfusion solution of hippocampal slices was measured. Results: Isoflurane treatment caused delayed elimination of population spike and improved the recovery of population spike; decreased frequency of hypoxic injury potential, postponed the onset of hypoxic injury potential and increased the duration of hypoxic injury potential. Isoflurane treatment also decreased the hypoxia-induced release of amino acid neurotransmitters such as aspartate, glutamate and glycine induced by hypoxia, but the levels of γ-aminobutyric acid were elevated. Morphological studies showed that isoflurane treatment attenuated edema of pyramid neurons in the CA1 region. It also reduced apoptosis as evident by lowered expression of caspase-3 and PARP genes. Conclusions: Isoflurane showed a neuro-protective effect on hippocampal neuron injury induced by hypoxia through suppression of apoptosis.

Resumo Justificativa e objetivos: Isoflurano é um éter volátil halogenado usado para anestesia por via inalatória. É amplamente usado na clínica como um anestésico para inalação. A lesão hipóxico-isquêmica neonatal ocorre no cérebro imaturo e resulta em morte celular tardia via excitotoxicidade e estresse oxidativo. Isoflurano mostrou ter propriedades neuroprotetoras que formam uma base benéfica para o seu uso tanto em cultura de células quanto em modelos animais, incluindo vários modelos de lesão cerebral. Nosso objetivo foi determinar o efeito neuroprotetor de isoflurano em hipóxia cerebral e elucidar o mecanismo subjacente. Métodos: Fatias de hipocampo, em fluido cerebrospinal artificial (CSFA) com glicose e privação de oxigênio, foram usadas como um modelo in vitro de hipóxia cerebral. O pico de população ortodrômica (PPO) e o potencial de lesão hipóxica (PLH) foram registrados nas regiões CA1 e CA3. A concentração de neurotransmissores de aminoácidos na solução de perfusão das fatias de hipocampo foi medida. Resultados: O tratamento com isoflurano retardou a eliminação do PPO e melhorou a recuperação do PPO; diminuiu a frequência do PLH, retardou o início do PLH e aumentou a duração do PLH. O tratamento com isoflurano também diminuiu a liberação de neurotransmissores de aminoácidos induzida pela hipóxia, como aspartato, glutamato e glicina, mas os níveis de ácido γ-aminobutírico (GABA) estavam elevados. Estudos morfológicos mostram que o tratamento de edema com isoflurano atenuou o edema de neurônios piramidais na região CA1. Também reduziu a apoptose, como mostrado pela expressão reduzida da caspase-3 e genes PARP. Conclusões: Isoflurano mostrou um efeito neuroprotetor na lesão neuronal no hipocampo induzida por hipóxia através da supressão de apoptose.

Morphological and immunohistochemical analysis of apoptosis in the cerebellum of rats subjected to focal cerebral ischemia with or without alcoholism model

ABSTRACT PURPOSE: To evaluated histopathological changes, morphometric and expression of proteins CASPASE-3, BCL-2 and XIAP related to apoptosis in the cerebellum after induction of temporary focal cerebral ischemia followed by reperfusion, with or without a model of chronic alcoholism. METHODS: Fifty Wistar rats were used and divided into: control group (C), sham group (S), ischemic group (I), alcoholic group (A), and ischemic and alcoholic group (IA). The cerebellum samples collected were stained for histopathological and morphometric analysis and immunohistochemistry study. RESULTS: Histopathological changes were observed a greater degree in animals in groups A and IA. The morphometric study showed no difference in the amount of cells in the granular layer of the cerebellum between the groups. The expression of CASPASE-3 was higher than BCL-2 and XIAP in the groups A and IA. CONCLUSION: We observed correlation between histopathological changes and the occurrence of apoptosis in cerebellar cortex.

Assessment transcallosal Diaschisis in a model of focal cerebral ischemia in rats / Evaluación de la diásquisis transcallosa en un modelo de isquemia cerebral focal en ratas

Objective: To evaluate transcallosal changes after a local ischemic injury in rats by using the monoclonal marker anti-NeuN (Mouse anti-neuronal nuclei). Methods: Twenty eight adult, male, Wistar rats were subjected to focal injury in the right hemisphere. The technique used was the experimental model of focal ischemic injury through intraluminal suture of the middle cerebral artery. Analyses were made for the five groups: and after the lesion (control), at 24 h, 96 h, 10 days and 20 days. Exofocal neuronal damage was inferred from neuronal immunoreactivity changes to NeuN. Results: In the cortex contralateral to the lesion, immunoreactivity was diminished. This was most notable in the supragranular layers 24 h post ischemia. After 96 h, there was a generalized diminishment of the inmmunoreactivity in supra and infragranular layers. At 10 and 20 days, the tissue recovered some NeuN immunoreactivity, but there were set changes in the VI layer. Conclusion: The immunoreactive changes to NeuN support the process of interhemispheric diaschisis. Changes in immunoreactivity could indicate metabolic stress secondary to the disruption in connectivity to the site of lesion.

Objetivo: Evaluar los cambios exofocales transcallosos después de lesión isquémica focal en ratas, mediante marcación inmunohistoquímica con el anticuerpo monoclonal anti-NeuN (Mouse Anti-Neuronal Nuclei). Métodos: Se intervinieron 28 ratas machos Wistar adultas. Mediante el modelo experimental de isquemia cerebral focal del territorio de la arteria cerebral media por filamento intraluminal, se les ocasionó una lesión focal en el hemisferio derecho. Posteriormente se evaluó el hemisferio contralateral, marcando la población neuronal con el anticuerpo monoclonal anti-NeuN. Se definieron cinco grupos de evaluación: uno de control, 24 h, 96 h, 10 días y 20 días. Se evaluaron los cambios neuronales exofocales después de la lesión con base en la observación de los cambios en la inmunoreactividad de las neuronas al NeuN. Resultados: Se redujo la inmunoreactividad en la corteza contralateral a la lesión. Este fenómeno fue más notable en las capas supragranulares después de 24 h post isquemia. Después de 96 h hubo una disminución generalizada de la inmmunoreactivity en las capas supra e infragranulares. A los 10 y 20 días, el tejido recobró alguna inmunoreactividad NeuN, estos cambios se dieron en la capa VI. Conclusiones: Los cambios inmunorreactivos a NeuN apoyan el proceso de diasquisis interhemisférica. Los cambios en la inmunorreactividad podrían indicar estrés metabólico secundario a la interrupción en la conectividad con el sitio de la lesión.

Multidetector computed tomography angiography in clinically suspected hyperacute ischemic stroke in the anterior circulation: an etiological workup in a cohort of Brazilian patients / Angiotomografia computadorizada multidetectores na avaliação da suspeita clínica de acidente vascular encefálico isquêmico hiperagudo da circulação anterior: determinação etiológica precoce em um grupo de pacientes brasileiros

Objective The potential of computed tomography angiography (CTA) was assessed for early determination of stroke subtypes in a Brazilian cohort of patients with stroke. Method From July 2011 to July 2013, we selected patients with suspected hyperacute stroke (< 6 hours). Intracranial and cervical arteries were scrutinized on CTA and their imaging features were correlated with concurrent subtype of stroke. Results Stroke was documented in 50/106 selected patients (47.2%) based on both clinical grounds and imaging follow-up (stroke group), with statistically significant arterial stenosis and vulnerable plaques on CTA. Intracranial large artery disease was demonstrated in 34% of patients in the stroke group. Partial territorial infarct prevailed (86%) while artery-to-artery embolization was the most common stroke mechanism (52%). Conclusion Multidetector CTA was useful for the etiologic work-up of hyperacute ischemic stroke and facilitated the knowledge about the topographic pattern of brain infarct in accordance with its causative mechanism. .

Objetivo Avaliar o potencial da angiotomografia computadorizada multidetectores (ATCM) na determinação etiológica precoce do acidente vascular encefálico (AVE) e correlacionar o mecanismo causal com o padrão de infarto. Método De Julho de 2011 a Julho de 2013, foram selecionados os pacientes com suspeita clínica de AVE hiperagudo. Os achados da ATCM dos vasos intracranianos e cervicais foram correlacionados com a etiologia final do evento. Resultados AVE foi confirmado em 50/106 pacientes (47,2%). Estes apresentaram alterações angiográficas estatisticamente mais relevantes. Aterosclerose dos grandes vasos intracranianos esteve presente em 34% destes pacientes. O padrão radiológico topográfico de infarto mais comum foi o infarto territorial parcial (86%). A embolização arterio-arterial foi o mecanismo mais prevalente (52%). Conclusão A utilização da ATCM traz benefícios na detecção etiológica precoce dos pacientes com suspeita de AVE hiperagudo, além de possibilitar o entendimento do padrão radiológico topográfico de acordo com o mecanismo causal do evento isquêmico. .

Role of cyclooxygenase-2 in Trypanosoma cruzi survival in the early stages of parasite host-cell interaction

Chagas disease, caused by the intracellular protozoan Trypanosoma cruzi, is a serious health problem in Latin America. During this parasitic infection, the heart is one of the major organs affected. The pathogenesis of tissue remodelling, particularly regarding cardiomyocyte behaviour after parasite infection and the molecular mechanisms that occur immediately following parasite entry into host cells are not yet completely understood. When cells are infected with T. cruzi, they develop an inflammatory response, in which cyclooxygenase-2 (COX-2) catalyses rate-limiting steps in the arachidonic acid pathway. However, how the parasite interaction modulates COX-2 activity is poorly understood. In this study, the H9c2 cell line was used as our model and we investigated cellular and biochemical aspects during the initial 48 h of parasitic infection. Oscillatory activity of COX-2 was observed, which correlated with the control of the pro-inflammatory environment in infected cells. Interestingly, subcellular trafficking was also verified, correlated with the control of Cox-2 mRNA or the activated COX-2 protein in cells, which is directly connected with the assemble of stress granules structures. Our collective findings suggest that in the very early stage of the T. cruzi-host cell interaction, the parasite is able to modulate the cellular metabolism in order to survives.

La combinación de atorvastatina y meloxicam inhibe la neuroinflamación y atenúa el daño celular en la isquemia cerebral experimental por embolia arterial / Atorvastatin-meloxicam association inhibits neuroinflammation and attenuates the cellular damage in cerebral ischemia by arterial embolism.

Introducción. El accidente cerebrovascular es la segunda causa de muerte y la primera de discapacidad en el mundo, y más de 85 % es de origen isquémico. Objetivo. Evaluar en un modelo de infarto cerebral por embolia arterial el efecto de la atorvastatina y el meloxicam, administrados por separado y de forma conjunta, sobre la respuesta neuronal, los astrocitos y la microglia. Materiales y métodos. Se sometieron ratas Wistar a embolia de la arteria carótida y a tratamiento con meloxicam y atorvastatina, administrados por separado y conjuntamente, a las 6, 24, 48 y 72 horas. Se evaluó la reacción de las proteínas COX-2, GFAP y OX-42 en las neuronas, los astrocitos y la microglia mediante inmunohistoquímica y estudios morfológicos y de densitometría. Los datos obtenidos se evaluaron por medio de un análisis de varianza y de pruebas no paramétricas de comparación múltiple. Resultados. La isquemia cerebral por embolia arterial incrementó significativamente (p<0,001) la reacción de los astrocitos y la microglia, en tanto que la atorvastatina y el meloxicam, administrados por separado y de forma conjunta, la redujeron. La isquemia produjo acortamiento de las proyecciones de los astrocitos, engrosamiento celular, ruptura de las expansiones protoplásmicas (clasmatodendrosis) y cambios morfológicos en la microglia propios de diversas etapas de actividad. En las zonas circundantes del foco se incrementó la reacción inmunológica de la COX-2 y se redujo en el foco isquémico, en tanto que el meloxicam y la atorvastatina redujeron significativamente (p<0,001) la reacción inmunológica en la zona circundante del foco, restableciendo la marcación de la ciclooxigenasa en el foco isquémico. Conclusión. La combinación de meloxicam y atorvastatina atenúa la respuesta de los astrocitos y la microglia en el proceso inflamatorio posterior a la isquemia cerebral por embolia arterial, reduciendo la degeneración neuronal y restableciendo el equilibrio morfológico y funcional del tejido nervioso.

Introduction: Stroke is the second leading cause of death and the first cause of disability in the world, with more than 85% of the cases having ischemic origin. Objective: To evaluate in an embolism model of stroke the effect of atorvastatin and meloxicam on neurons, astrocytes and microglia. This evaluation was done administering each medication individually and in association. Materials and methods: Wistar rats were subjected to carotid arterial embolism and treatment with meloxicam and atorvastatin at 6, 24, 48 and 72 hours. Using immunohistochemistry, we evaluated the immunoreactivity of COX-2 protein, GFAP and OX-42 in neurons, astrocytes and microglia by densitometric and morphological studies. Data were evaluated by variance analysis and non-parametric multiple comparison. Results: Cerebral ischemia by arterial embolism increased significantly the reactivity of microglia and astrocytes (p<0.001), whereas it was reduced by atorvastatin, meloxicam and their association. Ischemia produced astrocytic shortening, cellular thickening, protoplasmic rupture expansions (clasmatodendrosis) and microglial morphological changes characteristic of various activity stages. In perifocal areas, immunoreactivity of COX-2 was increased and in the ischemic focus it was reduced, while meloxicam and atorvastatin significantly reduced (p<0.001) perifocal immunoreactivity, restoring the marking of cyclooxygenase in the ischemic focus. Conclusion: These results suggest that the meloxicam-atorvastatin association attenuates astrocytic and microglial response in the inflammatory process after cerebral ischemia by arterial embolism, reducing neurodegeneration and restoring the morphological and functional balance of nervous tissue .

Analysis of the NMDA in focal cerebral ischemia in rats / Análisis del NMDA en isquemia cerebral focal en ratas

NMDAR (N-methyl-D-aspartate receptor) is one subtype of ionotrophic glutamate receptor which is extensively distributed in the central nervous system (CNS). In the mammalian CNS, NMDAR serves prominent roles in the pathophysiologic process of cerebral ischemia. This study aimed to investigate the pattern of expression of protein and gene of the excitatory neurotransmitter NMDAR in experimental focal cerebral ischemia and the hole of neuroprotection with hypothermia and ketoprofen. 120 rats were randomly divided into 6 groups (20 animals each): control - no surgery; sham - simulation of surgery; ischemic - focal ischemia for 1 hour, without reperfusion; ischemic + intraischemic hypothermia; ischemic + previous intravenous ketoprofen, and ischemic + hypothermia and ketoprofen. Ten animals from each experimental group were used to establish the volume of infarct. Transient focal cerebral ischemia was obtained in rats by occlusion of the middle cerebral artery with an intraluminal suture. The infarct volume was measured using morphometric analysis of infarct areas defined by triphenyl tetrazolium chloride and the patterns of expression of the protein and gene NMDA were evaluated by immunohistochemistry and quantitative real-time PCR, respectively. Increases in the protein and gene NMDA receptor in the ischemics areas were observed and these increases were reduced by hypothermia and ketoprofen. The increase in the NMDA receptor protein and gene expression observed in the ischemic animals was reduced by neuroprotection (hypothermia and ketoprofen). The NMDA receptor increases in the ischemic area suggests that the NMDA mediated neuroexcitotoxicity plays an important role in cell death and that the neuroprotective effect of both, hypothermia and ketoprofen is directly involved with the NMDA...

NMDAR (N-metil-D-aspartato) es un tipo de receptor de glutamato ionotrópico y está ampliamente distribuido en el sistema nervioso central (SNC). En el SNC de mamíferos, NMDAR se destaca de manera importante en el proceso fisiopatológico de la isquemia cerebral. Este estudio tuvo como objetivo investigar el patrón de expresión de proteínas y genes para el NMDA neurotransmisor excitatorio experimental de la isquemia cerebral focal y el vacío en la neuroprotección con hipotermia y ketoprofeno. Se dividieron 120 ratas aleatoriamente en grupos de 6 animales cada uno (20): Control - sin cirugía; Sham - simulación de cirugía; isquémicas - isquemia focal durante 1 hora, sin reperfusión isquémica; hipotermia intra-isquémica; isquemia; previa aplicación de ketoprofeno intravenoso, e hipotermia isquémica y ketoprofeno. Diez animales de cada grupo experimental fueron utilizados para establecer el volumen de infarto.La isquemia cerebral focal transitoria fue obtenida en ratas mediante oclusión de la arteria cerebral media con una sutura intraluminal. El volumen de infarto fue medido mediante análisis morfométrico de las áreas de infarto definidas por cloruro de trifenil tetrazolio y patrones de expresión de la proteína y el gen de NMDA, fueron evaluados por inmunohistoquímica y PCR cuantitativa en tiempo real, respectivamente. Se observaron aumentos en la proteína y en el gen del receptor de NMDA en las áreas isquémicas y estos aumentos fueron reducidos por la hipotermia y ketoprofeno. El aumento de la proteína del receptor de NMDA y la expresión génica observada en los animales isquémicos fue reducido mediante hipotermia y ketoprofeno. Los aumentos del receptor de NMDA en el área isquémica sugiere que la neuro excitotoxicidad mediada por NMDA desempeña un papel importante en la muerte celular y que el efecto neuroprotector de ambos, hipotermia y ketoprofeno está directamente relacionado al NMDA...

Role of PPAR, a Nuclear Hormone Receptor in Neuroprotection.

Peroxisome proliferator-activated receptors (PPARs) belong to the nuclear receptor superfamily. PPAR-alpha is involved in wound healing, stimulation of lipid and folic acid catabolism, inflammation control, inhibition of ureagenesis and peroxisome proliferation. The PPAR/ is involved wound healing, cell proliferation, embryo implantation, adipocyte differentiation, myelination alteration and apoptosis. The PPAR is involved in fat, lipid and calorie utilization, sugar control, inflammation control and macrophage (MQ) matutation. Homocysteine (Hcy) binds to nuclear peroxisome proliferator activated receptor. Increase in PPAR expression decreases the level of nitrotyrosine and increases endothelial nitric oxide concentration, decreases metalloproteinase activity and expression as well as elastinolysis and reverses Hcy-mediated vascular dysfunction. The PPAR initially recognized as a regulator of adipocyte development has become a potential therapeutic target for the treatment of diverse disorders. In addition, the activation of PPAR receptor ameliorates neurodegenerative disease. This review focuses on the recent knowledge of PPAR in neuroprotection and deals with the mechanism of neuroprotection of central nervous system disorder by PPAR.