Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 27
Filter
1.
Int. j. morphol ; 38(3): 523-529, June 2020. graf
Article in English | LILACS | ID: biblio-1098282

ABSTRACT

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.


Subject(s)
Animals , Rats , Brain Ischemia/genetics , Brain Ischemia/metabolism , Immunohistochemistry , Brain Ischemia/pathology , Brain Ischemia/therapy , Ketoprofen/pharmacology , Apoptosis/genetics , Neuroprotective Agents/pharmacology , Disease Models, Animal , Caspase 3/genetics , Caspase 8/genetics , Real-Time Polymerase Chain Reaction , Hypothermia, Induced
2.
Int. j. morphol ; 38(3): 616-621, June 2020. graf
Article in English | LILACS | ID: biblio-1098296

ABSTRACT

The chronic consumption of alcohol causes a worsening of the events that follow the cerebral ischemia. These events are regulated through the expression of several genes and microRNAs. The aimof this work was To analyze and describe the expression profile of PARP and AIF and miRNA-9 proteins in rats submitted to focal cerebral ischemia, associated or not with chronic alcoholism model. Methods: Twenty adult Wistar rats, subdivided into: control; ischemic; alcoholic and ischemic / alcoholized for immunohistochemical analysis and miRNA-9 gene expression. Results: There was a reduction in the protein expression of PARP-1 and a positive marking for AIF in the ischemic / alcoholized group. The miRNA-9 did not obtain significant expression. The association of ischemia with chronic alcohol use promoted a tendency to low expression of miRNA-9, low expression of PARP-1 and high expression of AIF, indicating an interference in the protective effect of miRNA-9 be observed in the other groups.


El consumo crónico de alcohol provoca un empeoramiento de los eventos que siguen a la isquemia cerebral. Estos eventos están regulados a través de la expresión de varios genes y microRNA. El objetivo de este trabajo fue analizar y describir el perfil de expresión de las proteínas PARP y AIF y microRNA-9 en ratas sometidas a isquemia cerebral focal, asociadas o no, con el modelo de alcoholismo crónico. Veinte ratas Wistar adultas se dividieron en: grupo control, isquémico alcohólico, e isquémico / alcoholizado para análisis inmunohistoquímico y expresión de genes microRNA-9. Resultados: Hubo una reducción en la expresión de proteínas de PARP-1 y un marcado positivo para AIF en el grupo isquémico / alcoholizado. No se observó una expresión significativa en el microRNA-9. La asociación de la isquemia con el consumo crónico de alcohol promovió una tendencia a la baja expresión de microRNA-9, baja expresión de PARP1 y alta expresión de AIF, lo que indica una interferencia en el efecto protector de microRNA-9 en los otros grupos.


Subject(s)
Animals , Rats , Brain Ischemia/metabolism , Alcoholism/metabolism , Immunohistochemistry , Brain Ischemia/genetics , Rats, Wistar , MicroRNAs/metabolism , Disease Models, Animal , Alcoholism/genetics , Apoptosis Inducing Factor/metabolism , Poly (ADP-Ribose) Polymerase-1/metabolism
3.
Biol. Res ; 52: 32, 2019. graf
Article in English | LILACS | ID: biblio-1038783

ABSTRACT

BACKGROUND: Long non-coding RNA H19 (H19) plays an important role by regulating protein expression in different tissues and organs of the body. However, whether H19 induces hypoxia/reoxygenation (h/R) injury via increase of autophagy in the hepatoma carcinoma cells is unknown. RESULTS: H19 was expressed in the hepatoma carcinoma cells (Hep G2 and HCCLM3 cells) and its expression was most in 8 h/24R. The knockdown of H19 and 3-MA (an autophagy inhibitor) protected against h/R-induced apoptosis, cell damage, the expression of cleaved caspase-3 and cleaved caspase-9, the release of cytochrome c (Cyt c). The knockdown of H19 and 3-MA also decreased the autophagic vesicles (AVs) and the expression of Beclin-1 and the ration of LC3-II/LC3-I, and increased cell viability, the expression of Bcl-2 and P62 and the phosphorylation of PI3K, Akt and mTOR. In addition, chloroquine (CQ, an inhibitor of autophagy flux) markedly decreased formation of autophagy flux (the ration of LC3-II/LC3-I). The results of the knockdown of H19 group were similar to those of the 3-MA (or CQ) group. Rapamycin (a mTOR inhibitor, an autophagy activator) further down-regulated h/R-induced decrease of the phosphorylated PI3K, Akt and mTOR. The knockdown of H19 cancelled the effect of rapamycin. The overexpression of H19 further expanded h/R-induced increase of the ration of LC3-II/LC3-I and decrease of the phosphorylated PI3K, Akt and mTOR. CONCLUSIONS: Our results suggest that the long non-coding RNA H19 induces h/R injury by up-regulation of autophagy via activation of PI3K-Akt-mTOR pathway in the hepatoma carcinoma cells.


Subject(s)
Humans , Reperfusion Injury/metabolism , Carcinoma, Hepatocellular/metabolism , RNA, Long Noncoding/metabolism , Liver Neoplasms/metabolism , Hypoxia/metabolism , Oxygen/metabolism , Autophagy/drug effects , Up-Regulation/physiology , Brain Ischemia/metabolism , Apoptosis/physiology , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology
4.
Acta cir. bras ; 33(2): 117-124, Feb. 2018. tab, graf
Article in English | LILACS | ID: biblio-886260

ABSTRACT

Abstract Purpose: To observe the efficacy of phosphocreatine pre-administration (PCr-PA) on X-linked inhibitor of apoptosis protein (XIAP), the second mitochondia-derived activator of caspase (Smac) and apoptosis in the ischemic penumbra of rats with focal cerebral ischemia-reperfusion injury (CIRI). Methods: A total of 60 healthy male Sprague Dawley (SD) rats were randomly divided into three groups (n=20): group A (the sham operation group), group B <intraperitoneally injected with 20 mg/kg (10 mg/ml) of saline before preparing the ischemia-reperfusion (IR) model>, and group C <intraperitoneally injected with 20 mg/kg (10 mg/ml) of PCr immediately before preparing the IR model>. After 24 h for reperfusion, the neurological function was evaluated and the tissue was sampled to detect expression of XIAP, Smac and caspase-3 positive cells in the ischemic penumbra so as to observe the apoptosis. Results: Compared with group B, neurological deficit scores, numbers of apoptotic cells, expression of Smac,caspase-9 and the numbers of Caspase-3 positive cells were decreased while expression of XIAP were increased in the ischemic penumbra of group C. Conclusions: Phosphocreatine pre-administration may elicit neuroprotective effects in the brain by increasing expression of X-linked inhibitor of apoptosis protein, reducing expression of second mitochondia-derived activator of caspase, and inhibiting the apoptosis in the ischemic penumbra.


Subject(s)
Humans , Animals , Male , Rats , Phosphocreatine/pharmacology , Cardiotonic Agents/pharmacology , Reperfusion Injury/metabolism , Brain Ischemia/metabolism , Mitochondrial Proteins/metabolism , Intracellular Signaling Peptides and Proteins/metabolism , X-Linked Inhibitor of Apoptosis Protein/metabolism , Random Allocation , Brain Ischemia/prevention & control , Rats, Sprague-Dawley , Apoptosis/drug effects , Neuroprotective Agents/pharmacology , Disease Models, Animal , Drug Evaluation, Preclinical , Apoptosis Regulatory Proteins , Caspase 3/metabolism
5.
Braz. j. med. biol. res ; 51(5): e6714, 2018. tab, graf
Article in English | LILACS | ID: biblio-889083

ABSTRACT

This study aimed to investigate the protective effect of salvinorin A on the cerebral pial artery after forebrain ischemia and explore related mechanisms. Thirty Sprague-Dawley rats received forebrain ischemia for 10 min. The dilation responses of the cerebral pial artery to hypercapnia and hypotension were assessed in rats before and 1 h after ischemia. The ischemia reperfusion (IR) control group received DMSO (1 µL/kg) immediately after ischemia. Two different doses of salvinorin A (10 and 20 µg/kg) were administered following the onset of reperfusion. The 5th, 6th, and 7th groups received salvinorin A (20 µg/kg) and LY294002 (10 µM), L-NAME (10 μM), or norbinaltorphimine (norBIN, 1 μM) after ischemia. The levels of cGMP in the cerebrospinal fluid (CSF) were also measured. The phosphorylation of AKT (p-AKT) was measured in the cerebral cortex by western blot at 24 h post-ischemia. Cell necrosis and apoptosis were examined by hematoxylin-eosin staining (HE) and TUNEL staining, respectively. The motor function of the rats was evaluated at 1, 2, and 5 days post-ischemia. The dilation responses of the cerebral pial artery were significantly impaired after ischemia and were preserved by salvinorin A treatment. In addition, salvinorin A significantly increased the levels of cGMP and p-AKT, suppressed cell necrosis and apoptosis of the cerebral cortex and improved the motor function of the rats. These effects were abolished by LY294002, L-NAME, and norBIN. Salvinorin A preserved cerebral pial artery autoregulation in response to hypercapnia and hypotension via the PI3K/AKT/cGMP pathway.


Subject(s)
Animals , Male , Rats , Cerebral Arteries/drug effects , Brain Ischemia/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Diterpenes, Clerodane/pharmacology , Signal Transduction , Cerebral Arteries/physiopathology , Brain Ischemia/drug therapy , Morpholines/administration & dosage , Chromones/administration & dosage , Rats, Sprague-Dawley , Cyclic GMP/cerebrospinal fluid , Cyclic GMP/metabolism , NG-Nitroarginine Methyl Ester , Diterpenes, Clerodane/antagonists & inhibitors , Disease Models, Animal , Naltrexone/administration & dosage , Naltrexone/analogs & derivatives
6.
Acta cir. bras ; 32(6): 459-466, June 2017. tab, graf
Article in English | LILACS | ID: biblio-886207

ABSTRACT

Abstract Purpose: To investigate the effects of dexmedetomidine (DEX) on amino acid contents and the cerebral ultrastructure of rats with cerebral ischemia-reperfusion injury (I/R). Methods: Thirty-six, male, Wistar rats were randomly divided into three groups: the sham operation group (group C), the ischemia-reperfusion group (group I/R), and the DEX group (group D). The middle cerebral artery occlusion model was prepared by the modified Longa method. The time of ischemia was 180 min, and 120 min after reperfusion, the amount of glutamate (Glu), and γ-aminobutyric acid (GABA) in the brain were measured, and the ultrastructure-level changes in the cerebral cortex were examined using electron microscopy. Results: Compared to group C, Glu contents in group D, and I/R significantly increased. Compared to group I/R, Glu contents in group D significantly decreased. Compared to group C, GABA contents in group D, and I/R significantly increased, and those in group D significantly increased, as compared to group I/R. The cerebral ultrastructure was normal in group C. Vacuolar degeneration in the plastiosome and nervous processes, was more critical than in group D. Vascular endothelial cells (VEC) were damaged. On the contrary, these changes in group D significantly improved. Conclusion: Dexmedetomidine is capable of decreasing glutamergic content, and increasing GABAergic content, in order to decrease the injury of the cerebral ultrastructure, following cerebral ischemia-reperfusion injury.


Subject(s)
Animals , Male , Rats , Reperfusion Injury/metabolism , Cerebral Cortex/chemistry , Brain Ischemia/drug therapy , Neuroprotective Agents/pharmacology , Dexmedetomidine/pharmacology , Glutamine/metabolism , Cerebral Cortex/ultrastructure , Brain Ischemia/metabolism , Rats, Wistar , gamma-Aminobutyric Acid/drug effects , gamma-Aminobutyric Acid/metabolism , Amino Acids/drug effects , Amino Acids/metabolism
7.
Arq. neuropsiquiatr ; 75(1): 30-35, Jan. 2017. graf
Article in English | LILACS | ID: biblio-838854

ABSTRACT

ABSTRACT Alcohol consumption aggravates injuries caused by ischemia. Many molecular mechanisms are involved in the pathophysiology of cerebral ischemia, including neurotransmitter expression, which is regulated by microRNAs. Objective: To evaluate the microRNA-219 and NMDA expression in brain tissue and blood of animals subjected to cerebral ischemia associated with alcoholism. Methods: Fifty Wistar rats were divided into groups: control, sham, ischemic, alcoholic, and ischemic plus alcoholic. The expression of microRNA-219 and NMDA were analyzed by real-time PCR. Results: When compared to the control group, the microRNA-219 in brain tissue was less expressed in the ischemic, alcoholic, and ischemic plus alcoholic groups. In the blood, this microRNA had lower expression in alcoholic and ischemic plus alcoholic groups. In the brain tissue the NMDA gene expression was greater in the ischemic, alcoholic, and ischemic plus alcoholic groups. Conclusion: A possible modulation of NMDA by microRNA-219 was observed with an inverse correlation between them.


RESUMO Algumas condições podem agravar os danos causados pelo processo isquêmico, tais como o consumo de álcool, e diversos mecanismos moleculares que estão envolvidos na fisiopatologia da isquemia cerebral, incluindo a expressão de neurotransmissores, e estes podem estar regulados por microRNAs. Objetivo: Avaliar a expressão de NMDA e do microRNA-219 no tecido cerebral e no sangue de animais submetidos à isquemia cerebral associada ao alcoolismo. Métodos: 50 ratos Wistar foram divididos em: controle, sham, isquêmico, alcoólico e isquêmico mais alcoólico. A expressão de microRNA-219 e de NMDA foram analisadas por PCR em tempo real. Resultados: Quando comparado com o grupo controle, o microRNA-219 no tecido cerebral foi menos expresso nos grupos isquêmico, alcoólico e associado. No sangue, este microRNA teve menor expressão no grupo alcoólico e no associado. Em relação à expressão do gene do NMDA, em tecido cerebral foi maior nos grupos isquêmico, alcoólico e no associado. Conclusão: Uma possível modulação de NMDA pelo microRNA-219 foi observada, com uma correlação inversa entre eles.


Subject(s)
Animals , Male , Rats , Brain Ischemia/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism , MicroRNAs/metabolism , Alcoholism/complications , Immunohistochemistry , Brain Ischemia/etiology , Rats, Wistar , Disease Models, Animal
8.
Acta cir. bras ; 31(9): 629-637, Sept. 2016. graf
Article in English | LILACS | ID: lil-795996

ABSTRACT

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.


Subject(s)
Animals , Male , Cerebellum/pathology , Brain Ischemia/pathology , Apoptosis , Ethanol/pharmacology , Alcoholism/pathology , Apoptosis Regulatory Proteins/metabolism , Immunohistochemistry , Reperfusion Injury/pathology , Cerebellum/drug effects , Cerebellum/metabolism , Brain Ischemia/metabolism , Rats, Wistar , Statistics, Nonparametric , Proto-Oncogene Proteins c-bcl-2/metabolism , Disease Models, Animal , Alcoholism/metabolism , X-Linked Inhibitor of Apoptosis Protein/metabolism , Caspase 3/metabolism
9.
Braz. j. med. biol. res ; 48(9): 798-804, Sept. 2015. ilus
Article in English | LILACS | ID: lil-756403

ABSTRACT

Stroke is the third most common cause of death worldwide, and most stroke survivors present some functional impairment. We assessed the striatal oxidative balance and motor alterations resulting from stroke in a rat model to investigate the neuroprotective role of physical exercise. Forty male Wistar rats were assigned to 4 groups: a) control, b) ischemia, c) physical exercise, and d) physical exercise and ischemia. Physical exercise was conducted using a treadmill for 8 weeks. Ischemia-reperfusion surgery involved transient bilateral occlusion of the common carotid arteries for 30 min. Neuromotor performance (open-field and rotarod performance tests) and pain sensitivity were evaluated beginning at 24 h after the surgery. Rats were euthanized and the corpora striata was removed for assay of reactive oxygen species, lipoperoxidation activity, and antioxidant markers. Ischemia-reperfusion caused changes in motor activity. The ischemia-induced alterations observed in the open-field test were fully reversed, and those observed in the rotarod test were partially reversed, by physical exercise. Pain sensitivity was similar among all groups. Levels of reactive oxygen species and lipoperoxidation increased after ischemia; physical exercise decreased reactive oxygen species levels. None of the treatments altered the levels of antioxidant markers. In summary, ischemia-reperfusion resulted in motor impairment and altered striatal oxidative balance in this animal model, but those changes were moderated by physical exercise.


Subject(s)
Animals , Male , Rats , Brain Ischemia/complications , Corpus Striatum/metabolism , Motor Disorders/prevention & control , Oxidative Stress/physiology , Physical Conditioning, Animal/physiology , Reperfusion Injury/complications , Brain Ischemia/metabolism , Catalase/metabolism , Disease Models, Animal , Glutathione/metabolism , Lipid Peroxidation , Motor Disorders/etiology , Oxidation-Reduction , Pain/physiopathology , Rats, Wistar , Reactive Oxygen Species/analysis , Superoxide Dismutase/metabolism
10.
Indian J Exp Biol ; 2014 Jun; 52(6): 597-605
Article in English | IMSEAR | ID: sea-153738

ABSTRACT

Limb remote ischemic postconditioning (LRIP) can reduce ischemia-reperfusion injury (IRI), but its mechanisms are still unclear. We hypothesize that LRIP reduces IRI by reversing eNOS uncoupling. Focal ischemia was induced in Sprague-Dawley rats by middle cerebral artery occlusion for 2 h followed by a 24 h reperfusion. Before this surgery, folic acid (FA) was administered to the drug treatment group by gavage for 11 days. After a 24 h reperfusion, behavioural testing, vascular function, NO concentration and superoxide dismutase activity in the serum were determined. In addition, the infarct size of the brain was also detected. The mRNA of eNOS, nNOS, GTP cyclohydrolase I (GTPCH), P22phox and xanthine oxidase (XO) in the ischemic region were detected by RT-PCR, and nitrotyrosine (Tyr-NO2) was detected using Western blot analysis. The results showed that LRIP, FA and FA+LRIP all could improve behavioural score, and increase NO–mediated endothelium-dependent vasomotor responses, reduce infarction of rats subjected to IRI. Western blot and RT-PCR analyses showed that the Tyr-NO2 levels and the mRNA expression of NADPH oxidase catalytic subunit P22phox and XO were up-regulated in the ischemic brain, which was significantly inhibited by LRIP, FA and FA+LRIP. The mRNA expression of the rate-limiting enzyme in BH4 synthesis, GTPCH, was down-regulated in the ischemic brain, which could be significantly augmented by LRIP and FA+LRIP. It can be concluded that IRI induces eNOS uncoupling in the cerebral ischemic region and LRIP partially reverses the eNOS uncoupling induced by IRI.


Subject(s)
Animals , Brain/blood supply , Brain/metabolism , Brain Ischemia/metabolism , Brain Ischemia/prevention & control , Extremities/blood supply , Ischemic Postconditioning/methods , Male , Nitric Oxide Synthase Type III/metabolism , Rats , Rats, Sprague-Dawley , Reperfusion Injury/metabolism , Reperfusion Injury/prevention & control
11.
Int. j. morphol ; 30(3): 979-985, Sept. 2012. ilus
Article in English | LILACS | ID: lil-665512

ABSTRACT

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...


Subject(s)
Animals , Rats , Brain Ischemia/metabolism , Brain Ischemia/pathology , Receptors, N-Methyl-D-Aspartate/metabolism , Ketoprofen/metabolism , Neuroprotective Agents/metabolism , Gene Expression , Hypothermia , Immunohistochemistry , Real-Time Polymerase Chain Reaction , Receptors, N-Methyl-D-Aspartate/genetics
12.
Article in English | WPRIM | ID: wpr-14964

ABSTRACT

Reactive oxygen species (ROS) contribute to the development of a number of neuronal diseases including ischemia. DJ-1, also known to PARK7, plays an important role in transcriptional regulation, acting as molecular chaperone and antioxidant. In the present study, we investigated whether DJ-1 protein shows a protective effect against oxidative stress-induced neuronal cell death in vitro and in ischemic animal models in vivo. To explore DJ-1 protein's potential role in protecting against ischemic cell death, we constructed cell permeable Tat-DJ-1 fusion proteins. Tat-DJ-1 protein efficiently transduced into neuronal cells in a dose- and time-dependent manner. Transduced Tat-DJ-1 protein increased cell survival against hydrogen peroxide (H2O2) toxicity and also reduced intracellular ROS. In addition, Tat-DJ-1 protein inhibited DNA fragmentation induced by H2O2. Furthermore, in animal models, immunohistochemical analysis revealed that Tat-DJ-1 protein prevented neuronal cell death induced by transient forebrain ischemia in the CA1 region of the hippocampus. These results demonstrate that transduced Tat-DJ-1 protein protects against cell death in vitro and in vivo, suggesting that the transduction of Tat-DJ-1 may be useful as a therapeutic agent for ischemic injuries related to oxidative stress.


Subject(s)
Animals , Blood-Brain Barrier/metabolism , Brain Ischemia/metabolism , CA1 Region, Hippocampal/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Gerbillinae , Intracellular Signaling Peptides and Proteins/administration & dosage , Lipid Peroxidation , Malondialdehyde/metabolism , Mice , Neuroprotective Agents/administration & dosage , Oncogene Proteins/administration & dosage , Oxidative Stress , Prosencephalon/drug effects , Rats , Recombinant Fusion Proteins/administration & dosage , tat Gene Products, Human Immunodeficiency Virus/administration & dosage
13.
Indian J Biochem Biophys ; 2011 Apr; 48(2): 73-81
Article in English | IMSEAR | ID: sea-135303

ABSTRACT

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.


Subject(s)
Animals , Brain Ischemia/metabolism , Brain Ischemia/pathology , Brain Ischemia/therapy , Cell Death , Central Nervous System/cytology , Central Nervous System/metabolism , Central Nervous System/pathology , Cytoprotection , Humans , Neurodegenerative Diseases/metabolism , Neurodegenerative Diseases/pathology , Neurodegenerative Diseases/therapy , Neurons/cytology , Neurons/pathology , Neuroprotective Agents/metabolism , PPAR gamma/metabolism
14.
Arq. bras. neurocir ; 29(2): 58-63, jun. 2010.
Article in Portuguese | LILACS | ID: lil-583496

ABSTRACT

Procede-se a uma revisão das alterações bioquímicas e hemodinâmicas causadas pela isquemia do tecido nervoso. Trata-se de uma visão introdutória que aborda a fisiopatologia e as repercussões da terapêutica sobre a hemodinâmica encefálica.


This is a review on the biochemical and hemodynamic alterations caused by the isquemia in the neural tissue. This text introduce the pathophysiology and the therapeutic effects of this ischemic alterations.


Subject(s)
Hemodynamics , Intracranial Hypertension , Brain Ischemia/classification , Brain Ischemia/complications , Brain Ischemia/physiopathology , Brain Ischemia/metabolism , Brain Ischemia/therapy , Acidosis
15.
Arq. bras. neurocir ; 29(2): 64-68, jun. 2010.
Article in Portuguese | LILACS | ID: lil-583497

ABSTRACT

O objetivo deste texto é o de estruturar e sistematizar novas hipóteses fisiopatológicas sobre as modificações hemodinâmicas do cérebro submetido à isquemia e à reperfusão. São propostas e analisadas hipóteses bioquímicas e hemodinâmicas do fenômeno da hipoperfusão pós-hiperemia.


The aim of this publication is to elaborate and discuss a new pathophysiological hypothesis about the haemodinamic modifications into the brain that occur after the reperfusion. Biochemical and haemodinamic hypothesis are proposed and analyzed, concerning the hipoperfusion following the hiperemia phenomenon.


Subject(s)
Hemodynamics , Hyperemia , Brain Ischemia/physiopathology , Brain Ischemia/metabolism , Reperfusion Injury
16.
Article in English | WPRIM | ID: wpr-44277

ABSTRACT

The aim of this study was to evaluate the effect of early motor balance and coordination training on functional recovery and brain plasticity in an ischemic rat stroke model, compared with simple locomotor exercise. Adult male Sprague-Dawley rats with cortical infarcts were trained under one of four conditions: nontrained control, treadmill training, motor training on the Rota-rod, or both Rota-rod and treadmill training. All types of training were performed from post-operation day 1 to 14. Neurological and behavioral performance was evaluated by Menzies' scale, the prehensile test, and the limb placement test, at post-operation day 1, 7, and 14. Both Rota-rod and treadmill training increased the expression of synaptophysin in subcortical regions of the ischemic hemisphere including the hippocampus, dentate gyrus, and thalamus, but did not affect levels of brain-derived neurotrophic factor or tyrosin kinase receptor B. The Rota-rod training also improved Menzies' scale and limb placement test scores, whereas the simple treadmill training did neither. The control group showed significant change only in Menzies' scale score. This study suggests that early motor balance and coordination training may induce plastic changes in subcortical regions of the ischemic hemisphere after stroke accompanied with the recovery of sensorimotor performance.


Subject(s)
Animals , Brain Ischemia/metabolism , Brain-Derived Neurotrophic Factor/metabolism , Dentate Gyrus/metabolism , Disease Models, Animal , Hippocampus/metabolism , Immunohistochemistry , Male , Motor Activity , Neuronal Plasticity/physiology , Physical Conditioning, Animal , Physical Therapy Modalities , Rats , Rats, Sprague-Dawley , Receptor, trkB/metabolism , Stroke/metabolism , Synaptophysin/metabolism , Thalamus/metabolism , Time Factors
17.
Acta cir. bras ; 22(2): 125-129, Mar.-Apr. 2007. graf
Article in English | LILACS | ID: lil-443689

ABSTRACT

PURPOSE: To evaluate the in vivo alterations on ketone bodies metabolism after cerebral ischemia/reperfusion through an experimental model of brain ischemia induced by simple occlusion of common carotid arteries (CCAs) in Wistar rats. METHODS: Forty-eight male Wistar rats were randomly distributed on two groups (S - Sham; T - Test) and further redistributed into four times sets of study. After bilateral occlusion of CCAs for 30min, the animals of group T were allowed reperfusion for 0, 5, 10 and 15min. Samples of cerebral tissue and systemic arterial blood were collected and the metabolites acetoacetate (ACT) and beta-hydroxybutyrate (BHB) were determined. RESULTS: Cerebral ACT and BHB levels increased significantly in Group T after 30min of carotid occlusion (time 0). The highest brain ketone bodies (ACT+BHB) concentration was verified at 5min of reperfusion, decreasing after 10min of recirculation. Systemic ketone bodies levels increased similarly between test and sham groups. Group S demonstrated a significant increase in cerebral and systemic ACT and BHB concentrations mainly after 40-45min of study. CONCLUSIONS: The partial transient acute global brain ischemia induced by the bilateral carotid occlusion in Wistar rats triggered ketogenesis probably due to a central stimulation of catecholamine secretion. There was an increased cerebral uptake of ketone bodies following brain ischemia, reaffirming these metabolites as alternative energy substrates under conditions of cerebral metabolic stress as well as its potential role on neuroprotection. The greatest changes in ketone bodies metabolism were verified at initial minutes of recirculation as a result of the reperfusion injury phenomenon.


OBJETIVO: Avaliar as alterações in vivo no metabolismo dos corpos cetônicos após isquemia/reperfusão cerebral através de um modelo experimental de isquemia cerebral induzido pela simples oclusão das artérias carótidas comuns (CCAs) em ratos Wistar. MÉTODOS: Quarenta e oito ratos Wistar machos foram distribuídos aleatoriamente em dois grupos (S - Controle; T - Teste) e cada um deles redistribuídos em quatro tempos de estudos. Após oclusão bilateral das CCAs por 30min, permitiu-se reperfusão aos animais do grupo T nos tempos 0, 5, 10 e 15min. Foram coletadas amostras de tecido cerebral e sangue arterial sistêmico e quantificados os metabólitos acetoacetato (ACT) e beta-hidroxibutirato (BHB). RESULTADOS: Os níveis cerebrais de ACT e BHB aumentaram significantemente no Grupo T após 30min de oclusão carotídea (tempo 0). A maior concentração de corpos cetônicos (ACT+BHB) foi verificada aos 5min de reperfusão, diminuindo após 10min de recirculação. Os níveis de corpos cetônicos sistêmicos aumentaram de modo semelhante entre os grupos teste e controle. O Grupo S demonstrou significante aumento nas concentrações sistêmicas e cerebrais de ACT e BHB principalmente após 40-45min de estudo. CONCLUSÕES: A isquemia cerebral aguda transitória e parcial induzida pela oclusão bilateral das carótidas em ratos Wistar ativou a cetogênese provavelmente devido à estimulação central da secreção de catecolaminas. Houve um aumento da captação dos corpos cetônicos após isquemia cerebral, reafirmando esses metabólitos como substratos energéticos alternativos em condições de estresse metabólico cerebral, bem como suas potencialidades na neuroproteção. As maiores alterações no metabolismo dos corpos cetônicos foram verificadas nos minutos iniciais de recirculação como resultado do fenômeno da lesão de reperfusão.


Subject(s)
Animals , Male , Rats , Brain Ischemia/metabolism , Carotid Artery, Common , Carotid Artery Diseases/physiopathology , Ketone Bodies/metabolism , Reperfusion Injury/metabolism , /blood , Acetoacetates/blood , Brain Ischemia/physiopathology , Disease Models, Animal , Energy Metabolism , Oxidative Stress/physiology , Random Allocation , Rats, Wistar , Reperfusion Injury/physiopathology , Statistics, Nonparametric , Time Factors
18.
Article in English | WPRIM | ID: wpr-125140

ABSTRACT

Platelet activation has a critical role in arterial disorders. In this study, we showed that the upregulation of P-selectin expression on platelets was related with clinical worsening in acute ischemic stroke. We serially (within 24 hr, at 72 hr, and 7 days) measured the expression of P-selectin on platelets in patients with acute ischemic stroke (n=45) and investigated the correlation between their extents and clinical severity of ischemic stroke. A significant relationship between the P-selectin expressions and National Institute of Health Stroke Scale (NIHSS) was observed at 72 hr and 7 days after ischemic stroke onset. Patients with clinical deterioration showed significantly increased expression of P-selectin on platelets as compared to those without deterioration. These results suggest that the P-selectin expression on platelets may contribute to the aggravation of clinical course in acute ischemic stroke. Thus, adequate manipulation of activated platelets is an important therapeutic strategy in acute ischemic stroke.


Subject(s)
Adult , Aged , Aged, 80 and over , Arteriosclerosis/pathology , Blood Platelets/metabolism , Brain Ischemia/metabolism , Cell Adhesion Molecules/metabolism , Cerebrovascular Disorders/metabolism , Disease Progression , Female , Flow Cytometry , Humans , Male , Middle Aged , P-Selectin/biosynthesis , Signal Transduction , Stroke/metabolism , Time Factors , Up-Regulation
19.
Arq. neuropsiquiatr ; 58(2B): 583-8, jun. 2000. ilus
Article in English | LILACS | ID: lil-264465

ABSTRACT

PURPOSE: To analyze the main aspects of neuroprotection and excitotoxicity. DISCUSSION: This is a significant theory on the pathophysiology of cerebral ischemia; it is based on the release of excitatory aminoacid (EAA), mainly glutamate. The sequence starts with a decrease of the blood flow and ends in neuronal death. The main stages of this reaction are herein presented and discussed. An in depth study of the effects of the excessive intracellular calcium is undertaken. Neuroprotectors (NP) are a group of drugs that reduce the excitotoxicity, opposing the excessive release of EAA and its intracellular effects. Neuroprotectors represent a rational approach to stroke treatment and offer a number of potential advantages. They prevent or limit ischemia-induced damage. CONCLUSION: There are many experimental and clinical NP trials. A minimum of 800 trials are currently under study worldwide. The most important NP subgroups are: N-methyl D-aspartate (NMDA) antagonists, gamma-amino butyric acid (GABA) agonists, amino-hydroxy-methyl-isoxalone propionic acid (AMPA) antagonists, reducers of intracellular Ca++ inhibitors of nitric oxide modulation pathway free radicals scavengers, sodium channel antagonists, glutamate release inhibitor, growth factors, hypothermia and potassium channel activators.


Subject(s)
Humans , Brain Ischemia/physiopathology , Neuroprotective Agents/pharmacology , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Brain Ischemia/metabolism , Brain Ischemia/prevention & control , Brain/metabolism , Excitatory Amino Acid Antagonists/pharmacology , Neurotoxins/pharmacology
20.
Braz. j. med. biol. res ; 32(10): 1295-302, Oct. 1999. graf
Article in English | LILACS | ID: lil-252281

ABSTRACT

Brain ischemia followed by reperfusion causes neuronal death related to oxidative damage. Furthermore, it has been reported that subjects suffering from ischemic cerebrovascular disorders exhibit changes in circulating platelet aggregation, a characteristic that might be important for their clinical outcome. In the present investigation we studied tert-butyl hydroperoxide-initiated plasma chemiluminescence and thiol content as measures of peripheral oxidative damage in naive and preconditioned rats submitted to forebrain ischemia produced by the 4-vessel occlusion method. Rats were submitted to 2 or 10 min of global transient forebrain ischemia followed by 60 min or 1, 2, 5, 10 or 30 days of reperfusion. Preconditioned rats were submitted to a 10-min ischemic episode 1 day after a 2-min ischemic event (2 + 10 min), followed by 60 min or 1 or 2 days of reperfusion. It has been demonstrated that such preconditioning protects against neuronal death in rats and gerbils submitted to a lethal (10 min) ischemic episode. The results show that both 2 and 10 min of ischemia cause an increase of plasma chemiluminescence when compared to control and sham rats. In the 2-min ischemic group, the effect was not present after reperfusion. In the 10-min ischemic group, the increase was present up to 1 day after recirculation and values returned to control levels after 2 days. However, rats preconditioned to ischemia (2 + 10 min) and reperfusion showed no differences in plasma chemiluminescence when compared to controls. We also analyzed plasma thiol content since it has been described that sulfhydryl (SH) groups significantly contribute to the antioxidant capacity of plasma. There was a significant decrease of plasma thiol content after 2, 10 and 2 + 10 min of ischemia followed by reperfusion when compared to controls. We conclude that ischemia may cause, along with brain oxidative damage and cell death, a peripheral oxidative damage that is reduced by the preconditioning phenomenon


Subject(s)
Rats , Animals , Male , Brain Ischemia/blood , Ischemic Preconditioning , Oxidative Stress , Sulfhydryl Compounds/blood , tert-Butylhydroperoxide/blood , Antioxidants , Brain Ischemia/metabolism , Cell Death , Luminescent Measurements , Rats, Wistar , Reperfusion , Sulfhydryl Compounds/metabolism , tert-Butylhydroperoxide/metabolism , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL