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1.
Braz. j. med. biol. res ; 54(4): e10498, 2021. graf
Article in English | LILACS | ID: biblio-1153543

ABSTRACT

It is known that neuronal apoptosis contributes to pathology of cerebral ischemia injury. Zonisamide (ZNS) has shown anti-apoptosis effects in recent studies. The present study investigated whether the anti-apoptotic effect can account for the neuroprotective action of ZNS on cerebral ischemia. Neuronal cells were maintained under oxygen-glucose deprivation conditions to simulate cerebral ischemia and treated with ZNS simultaneously. The apoptosis of the cells and expression of apoptosis-related proteins were investigated by flow cytometry and western blot analysis, respectively. A cerebral ischemia mouse model was created via middle cerebral artery occlusion, and the mice were treated with ZNS. Neurological deficit scores and infarct volumes of the cerebral ischemia mice were measured. The apoptosis status of the neuronal cells was evaluated by TUNEL staining. In vitro, the ZNS treatment inhibited both the apoptosis of the neuronal cells and apoptosis-related protein expression (caspase-3, caspase-8, and calpain-1) induced by the oxygen-glucose deprivation. The anti-apoptosis effect of ZNS could occur through the blocking of reactive oxygen species. Moreover, ZNS treatment significantly ameliorated neurological deficits and reduced infarct volumes in the cerebral ischemia mice model. In this study, ZNS exerted neuroprotective effects by inhibition of apoptosis in neuronal cells in cerebral ischemia. Therefore, ZNS might be a promising therapy for cerebral ischemia.


Subject(s)
Animals , Rats , Reperfusion Injury , Brain Ischemia/drug therapy , Neuroprotective Agents/pharmacology , Apoptosis , Infarction, Middle Cerebral Artery/drug therapy , Zonisamide/pharmacology
2.
Article in Chinese | WPRIM | ID: wpr-878984

ABSTRACT

One new and two known dammarane-type saponins were isolated from the leaves of Gynostemma pentaphyllum using various chromatographic methods. Their structures were identified by HR-ESI-MS,~( 1)H-NMR, ~(13)C-NMR, 2 D-NMR spectra as 2α,3β,12β,20,24(S)-tetrahdroxydammar-25-en-3-O-[β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-β-D-xylopyranosyl(1→6)-β-D-glucopyranoside(1, a new compound, namely gypenoside J5) and 2α,3β,12β,20,24(R)-tetrahdroxydammar-25-en-3-O-[β-D-glucopyranosyl(1→2)-β-D-glucopyranosyl]-20-O-β-D-xylopyranosyl(1→6)-β-D-glucopyranoside(2) and 2α,3β,12β,20-tetrahydroxy-25-hydroperoxy-dammar-23-en-3-O-[β-D-glucopyranosyl(1→2)][β-D-glucopyranosyl]-20-O-[β-D-xylopyranosyl(1→6)]-β-D-glucopy-ranoside(3), respectively. Compounds 1 and 2 were a pair of C-24 epimers. All compounds showed weak cytotoxicity agxinst H1299, HepG2, PC-3, SH-SY5 Y cancer cell lines. However, they exerted protective effect against SH-SY5 Y cellular damage induced by H_2O_2 dose-dependently, of which compound 1 displayed the strongest antioxidant effect. The present study suggested that G. pentaphyllum has antioxidative potential and the saponins from G. pentaphyllum are considered as the active compounds with neuroprotecitve effect.


Subject(s)
Gynostemma , Molecular Structure , Neuroprotective Agents/pharmacology , Saponins/pharmacology , Triterpenes/pharmacology
3.
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
4.
Braz. arch. biol. technol ; 63: e20190072, 2020. graf
Article in English | LILACS | ID: biblio-1132180

ABSTRACT

Abstract In live organisms, there is a balance between the production of reactive oxygen species (ROS) and their neutralization. The increased level of these species leads to a condition called redox imbalance. The aim of this study was to evaluate the protective action of isobenzofuranones in primary cultures of hippocampal neurons subjected to redox imbalance. To accomplish this, MTT and LIVE/DEAD assays were initially performed. In the cultures pretreated with isobenzofuranones 1 and 2, there was a higher number of live cells when compared to that in the untreated ones. Regarding redox imbalance, there was a significant increase in the intracellular levels of ROS. The cultures pretreated with isobenzofuranones showed a reduction in ROS levels. Lipid peroxidation caused by oxidative damage was significantly reduced in the cultures pretreated with isobenzofuranones 1 and 2. Taken together, these data show the ability of isobenzofuranones 1 and 2 to significantly minimize cytotoxicity, cell death, intracellular levels of ROS and lipid peroxidation induced by redox imbalance. These results suggest that isobenzofuranones 1 and 2 represent a possible alternative therapy for the neurodegenerative disturbances that are triggered by ROS production increases.


Subject(s)
Animals , Male , Mice , Oxidation-Reduction/drug effects , Benzofurans/pharmacology , Reactive Oxygen Species , Neuroprotective Agents/pharmacology , Hydrogen Peroxide , Benzofurans/chemical synthesis , Cell Death , Primary Cell Culture , Hippocampus/cytology , Neurons/metabolism
5.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 459-479, sept. 2019. ilus
Article in English | LILACS | ID: biblio-1008268

ABSTRACT

Neuronal cell damage is often caused by prolonged misuse of Methylphenidate (MPH). Topiramate (TPM) carries neuroprotective properties but its assumed mechanism remains unclear. The present study evaluates in vivo role of various doses of TPM and its mechanism against MPH-induced motor activity and related behavior disorder. Thus, we used domoic acid (DOM), bicuculline (BIC), Ketamine (KET), Yohimibine (YOH) and Haloperidole (HAL) as AMPA/kainite, GABAA, NMDA, ɑ2 adrenergic and D2 of dopamine receptor antagonists respectively. Open Field Test (OFT), Elevated Plus Maze (EPM) and Forced Swim Test (FST) were used to study motor activity, anxiety and depression level. TPM (100 and 120 mg/kg) reduced MPH-induced rise and inhibited MPH-induced promotion in motor activity disturbance, anxiety and depression. Pretreatment of animals with KET, HAL, YOH and BIC inhibited TPM- improves anxiety and depression through the interacting with Dopaminergic, GABAA, NMDA and ɑ2-adrenergic receptors.


El daño a las células neuronales a menudo es causado por el uso prolongado de metilfenidato (MPH). El topiramato (TPM) tiene propiedades neuroprotectoras, pero su mecanismo de acción no es claro. El presente estudio evalúa el papel in vivo de varias dosis de TPM y su mecanismo contra la actividad motora inducida por MPH y el trastorno de comportamiento relacionado. Utilizamos ácido domoico (DOM), bicuculina (BIC), ketamina (KET), yohimbina (YOH) y haloperidol (HAL), así como antagonistas AMPA/kainato, GABAA, NMDA, ɑ2-adrenérgico y D2 dopaminérgicos, respectivamente. Se utilizaron las pruebas de campo abierto (OFT), elevación de laberinto (EPM) y natación forzada (FST) para estudiar la actividad motora, la ansiedad y el nivel de depresión. El TPM (100 y 120 mg/kg) redujo el aumento inducido por MPH e inhibió la promoción inducida por MPH en la alteración de la actividad motora, la ansiedad y la depresión. El tratamiento previo de animales con KET, HAL, YOH y BIC inhibió el TPM, mejora la ansiedad y la depresión a través de la interacción con los receptores dopaminérgicos, GABAA, NMDA y ɑ2-adrenérgico.


Subject(s)
Animals , Male , Rats , Behavior, Animal/drug effects , Neuroprotective Agents/pharmacology , Topiramate/pharmacology , Mental Disorders/prevention & control , Methylphenidate/adverse effects , Rats, Wistar , Neurotransmitter Agents/metabolism , Mental Disorders/chemically induced , Motor Activity/drug effects
6.
Arq. neuropsiquiatr ; 77(1): 39-46, Jan. 2019. tab, graf
Article in English | LILACS | ID: biblio-983876

ABSTRACT

ABSTRACT Objective: We investigated the protective effect of the extract of the Camellia japonica L. flower on cerebral ischemia-reperfusion injury in rats. Methods: The rat ischemia-reperfusion injury was induced by middle cerebral artery occlusion for 90 minutes and reperfusion for 48 hours. The animals received an intravenous injection once a day of 20, 40, 80 mg/kg extract of C. japonica for three consecutive days before the ischemia reperfusion. The learning and memory function, the infarct volume, serum malondialdehyde (MDA) level and lactate dehydrogenase activity, and extravasation of immunoglobulin G (IgG) into cerebral parenchyma were assessed as the cell damage index. Results: Pretreatment with extract of C. japonica markedly reduced the infarct volume, serum malondialdehyde level and lactate dehydrogenase activity, and markedly inhibited the extravasation of IgG. Moreover, pretreatment with extract of C. japonica may also inhibit the learning and memory deficits induced by an ischemia-reperfusion injury. Conclusion: It was concluded that pretreatment with extract of C. japonica has a protective effect on cerebral ischemia-reperfusion injury in rats.


RESUMO Objetivo: Investigamos o efeito protetor do extrato da flor de Camellia japonica L. (ECJ) na lesão de reperfusão isquêmica cerebral (I/R) em ratos. Métodos: A lesão de I/R de rato foi induzida por uma oclusão da artéria cerebral média por 90 minutos e reperfusão por 48 horas. Os animais receberam uma injeção intravenosa uma vez ao dia de 20, 40, 80 mg/kg de ECJ por três dias consecutivos antes da I/R. A função de aprendizagem e memória, o volume do infarto, o nível sérico de malondialdeído (MDA), a atividade da desidrogenase láctica e o extravasamento de imunoglobulina (IgG) no parênquima cerebral foram avaliados como índices de dano celular. Resultados: O pré-tratamento com ECJ reduziu acentuadamente o volume do infarto, o nível sérico de MDA e a atividade da desidrogenase láctica, e inibiu marcadamente o extravasamento de IgG. Além disso, o pré-tratamento com ECJ também poderia inibir os déficits de aprendizado e memória induzidos pela lesão de I/R. Conclusão: O pré-tratamento com ECJ tem um efeito protetor contra lesão cerebral de I/R em ratos.


Subject(s)
Animals , Male , Female , Plant Extracts/pharmacology , Reperfusion Injury/prevention & control , Brain Ischemia/prevention & control , Neuroprotective Agents/pharmacology , Camellia/chemistry , Swimming/physiology , Time Factors , Immunoglobulin G/blood , Nimodipine/pharmacology , Random Allocation , Reproducibility of Results , Treatment Outcome , Rats, Sprague-Dawley , Disease Models, Animal , L-Lactate Dehydrogenase/analysis , Malondialdehyde/blood
7.
Clinics ; 74: e674, 2019. tab, graf
Article in English | LILACS | ID: biblio-1019700

ABSTRACT

OBJECTIVE: To evaluate the effects of interleukin-6 (IL-6) and erythropoietin (EPO) in experimental acute spinal cord injury (SCI) in rats. METHODS: Using standardized equipment, namely, a New York University (NYU) Impactor, a SCI was produced in 50 Wistar rats using a 10-g weight drop from a 12.5-mm height. The rats were divided into the following 5 groups of 10 animals each: "Group EPO", treated with erythropoietin only; "Group EPO + IL-6", treated with both substances; "Group IL-6", receiving IL-6 administration only; "Group Placebo", receiving a placebo solution; and "Group Sham", submitted to an incomplete procedure (only laminectomy, without SCI). All drugs and the placebo solution were administered intraperitoneally for three weeks. The animals were followed up for 42 days. Functional motor recovery was monitored by the Basso, Beattie, and Bresnahan (BBB) scale on days 2, 7, 14, 21, 28, 35 and 42. Motor-evoked potential tests were performed on the 42nd day. Histological analysis was performed after euthanasia. RESULTS: The group receiving EPO exhibited superior functional motor results on the BBB scale. IL-6 administration alone was not superior to the placebo treatment, and the IL-6 combination with EPO yielded worse results than did EPO alone. CONCLUSIONS: Using EPO after acute SCI in rats yielded benefits in functional recovery. The combination of EPO and IL-6 showed benefits, but with inferior results compared to those of isolated EPO; moreover, isolated use of IL-6 resulted in no benefit.


Subject(s)
Animals , Male , Rats , Spinal Cord Injuries/drug therapy , Erythropoietin/therapeutic use , Interleukin-6/therapeutic use , Evoked Potentials, Motor/drug effects , Spinal Cord Injuries/pathology , Erythropoietin/pharmacology , Interleukin-6/pharmacology , Rats, Wistar , Neuroprotective Agents/pharmacology , Recovery of Function/drug effects , Disease Models, Animal
8.
Acta cir. bras ; 34(12): e201901205, 2019. graf
Article in English | LILACS | ID: biblio-1054687

ABSTRACT

Abstract Purpose To investigate the effects of huperzine A (HupA) on hippocampal inflammatory response and neurotrophic factors in aged rats after anesthesia. Methods Thirty-six Sprague Dawley rats (20-22 months old) were randomly divided into control, isofluran, and isoflurane+HupA groups; 12 rats in each group. The isoflurane+HupA group was intraperitoneally injected with 0.2 mg/kg of HupA. After 30 min, isoflurane inhalation anesthesia was performed in the isoflurane and isoflurane+HupA groups. After 24 h from anesthesia, Morris water maze experiment and open-field test were performed. Hippocampal inflammatory and neurotrophic factors were determined. Results Compared with isoflurane group, in isofluran+HupA group the escape latency of rats was significantly decreased (P < 0.05), the original platform quadrant residence time and traversing times were significantly increased (P < 0.05), the central area residence time was significantly increased (P < 0.05), the hippocampal tumor necrosis factor α, interleukin 6 and interleukin 1β levels were significantly decreased (P < 0.05), and the hippocampal nerve growth factor, brain derived neurotrophic factor and neurotrophin-3 levels were significantly increased (P < 0.05). Conclusion HupA may alleviate the cognitive impairment in rats after isoflurane anesthesia by decreasing inflammatory factors and increasing hippocampal neurotrophic factors in hippocampus tissue.


Subject(s)
Humans , Animals , Male , Sesquiterpenes/pharmacology , Neuroprotective Agents/pharmacology , Anesthetics, Inhalation/adverse effects , Alkaloids/pharmacology , Hippocampus/drug effects , Nerve Growth Factors/drug effects , Enzyme-Linked Immunosorbent Assay , Random Allocation , Reproducibility of Results , Interleukin-6/analysis , Rats, Sprague-Dawley , Maze Learning , Interleukin-1beta/analysis , Hippocampus/metabolism , Isoflurane/adverse effects , Anesthesia/adverse effects , Nerve Growth Factors/analysis
9.
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
10.
Clinics ; 73: e161, 2018. graf
Article in English | LILACS | ID: biblio-890761

ABSTRACT

OBJECTIVES: Erythropoietin may have neuroprotective potential after ischemia of the central nervous system. Here, we conducted a study to characterize the protective effects of erythropoietin on retinal ganglion cells and gliotic reactions in an experimentally induced oligemia model. METHODS: Rats were subjected to global oligemia by bilateral common carotid artery occlusion and then received either vehicle or erythropoietin via intravitreal injection after 48 h; they were euthanized one week after the injection. The densities of retinal ganglion cells and contents of glial fibrillary acidic protein (astrocytes/Müller cells) and cluster of differentiation 68 clone ED1 (microglia/macrophages), assessed by fluorescence intensity, were evaluated in frozen retinal sections by immunofluorescence and epifluorescence microscopy. RESULTS: Retinal ganglion cells were nearly undetectable one week after oligemia compared with the sham controls; however, these cells were partially preserved in erythropoietin-treated retinas. The contents of glial fibrillary acidic protein and cluster of differentiation 68 clone ED1, markers for reactive gliosis, were significantly higher in retinas after bilateral common carotid artery occlusion than those in both sham and erythropoietin-treated retinas. CONCLUSIONS: The number of partially preserved retinal ganglion cells in the erythropoietin-treated group suggests that erythropoietin exerts a neuroprotective effect on oligemic/ischemic retinas. This effect could be related to the down-modulation of glial reactivity, usually observed in hypoxic conditions, clinically observed during glaucoma or retinal artery occlusion conditions. Therefore, glial reactivity may enhance neurodegeneration in hypoxic conditions, like normal-tension glaucoma and retinal ischemia, and erythropoietin is thus a candidate to be clinically applied after the detection of decreased retinal blood flow.


Subject(s)
Animals , Male , Retinal Ganglion Cells/drug effects , Erythropoietin/pharmacology , Neuroprotective Agents/pharmacology , Glial Fibrillary Acidic Protein/drug effects , Retinal Diseases/pathology , Cell Count , Hematopoietic Cell Growth Factors/pharmacology , Rats, Wistar , Carotid Artery, Common/surgery , Carotid Artery Injuries/surgery , Disease Models, Animal , Ectodysplasins/drug effects
11.
Acta cir. bras ; 32(10): 862-872, Oct. 2017. graf
Article in English | LILACS | ID: biblio-886174

ABSTRACT

Abstract Purpose: To investigate whether the neuroprotective effect of TSA on cerebral ischemia reperfusion injury is mediated by the activation of Akt/GSK-3β signaling pathway. Methods: Mice were randomly divided into four groups (n=15): sham group (S); ischemia reperfusion group (IR); ischemia reperfusion and pretreated with TSA group (IR+T); ischemia reperfusion and pretreated with TSA and LY294002 group (IR+T+L). The model of cerebral ischemia reperfusion was established by 1h of MCAO following 24h of reperfusion. TSA (5mg/kg) was intraperitoneally given for 3 days before MCAO, Akt inhibitor, LY294002 (15 nmol/kg) was injected by tail vein 30 min before the MCAO. Results: TSA significantly increased the expression of p-Akt, p-GSK-3β proteins and the levels of SOD, Bcl-2, reduced the infarct volume and the levels of MDA, ROS, TNF-α, IL-1β, Bax, Caspase-3, TUNEL and attenuated neurological deficit in mice with transient MCAO, LY294002 weakened such effect of TSA dramatically. Conclusions: TSA could significantly decrease the neurological deficit and reduce the cerebral infarct volume, oxidative stress, inflammation, as well as apoptosis during cerebral ischemia reperfusion injury, which was achieved by activation of the Akt/GSK-3β signaling pathway.


Subject(s)
Animals , Male , Rats , Signal Transduction/drug effects , Ischemic Attack, Transient/metabolism , Neuroprotective Agents/pharmacology , Glycogen Synthase Kinase 3/drug effects , Proto-Oncogene Proteins c-akt/drug effects , Histone Deacetylase Inhibitors/pharmacology , Signal Transduction/physiology , Ischemic Attack, Transient/physiopathology , Glycogen Synthase Kinase 3/metabolism , Disease Models, Animal , Mice, Inbred BALB C
12.
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
13.
Braz. j. med. biol. res ; 50(4): e5561, 2017. graf
Article in English | LILACS | ID: biblio-839280

ABSTRACT

The aim of this study was to investigate whether exogenous retinoic acid (RA) can upregulate the mRNA and protein expression of growth-associated protein 43 (GAP-43), thereby promoting brain functional recovery in a rat distal middle cerebral artery occlusion (MCAO) model of ischemia. A total of 216 male Sprague Dawley rats weighing 300–320 g were divided into 3 groups: sham-operated group, MCAO+vehicle group and MCAO+RA group. Focal cortical infarction was induced with a distal MCAO model. The expression of GAP-43 mRNA and protein in the ipsilateral perifocal region was assessed using qPCR and immunocytochemistry at 1, 3, 7, 14, 21, and 28 days after distal MCAO. In addition, an intraperitoneal injection of RA was given 12 h before MCAO and continued every day until the animal was sacrificed. Following ischemia, the expression of GAP-43 first increased considerably and then decreased. Administration of RA reduced infarction volume, promoted neurological functional recovery and upregulated expression of GAP-43. Administration of RA can ameliorate neuronal damage and promote nerve regeneration by upregulating the expression of GAP-43 in the perifocal region after distal MCAO.


Subject(s)
Animals , Male , GAP-43 Protein/metabolism , Gene Expression/drug effects , Infarction, Middle Cerebral Artery/prevention & control , Neuroprotective Agents/pharmacology , Tretinoin/pharmacology , Up-Regulation/drug effects , Brain Ischemia/prevention & control , GAP-43 Protein/genetics , Immunohistochemistry , Infarction, Middle Cerebral Artery/metabolism , Infarction, Middle Cerebral Artery/pathology , Random Allocation , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Reproducibility of Results , Time Factors
14.
Rev. bras. anestesiol ; 66(6): 613-621, Nov.-Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-829707

ABSTRACT

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.


Subject(s)
Animals , Female , Pregnancy , Rats , Hypoxia, Brain/prevention & control , Brain Ischemia/pathology , Apoptosis/drug effects , Neuroprotective Agents/pharmacology , Anesthetics, Inhalation/pharmacology , Isoflurane/pharmacology , Hypoxia, Brain/pathology , Rats, Sprague-Dawley , CA1 Region, Hippocampal/pathology , CA3 Region, Hippocampal/pathology , Glucose/deficiency , Hippocampus/pathology , Animals, Newborn
15.
Rev. chil. neurocir ; 42(2): 144-150, nov. 2016. tab
Article in Spanish | LILACS | ID: biblio-869767

ABSTRACT

El Traumatismo Raquimedular (TRM) implica todas las lesiones traumáticas que dañan los huesos, ligamentos, músculos, cartílagos, estructuras vasculares, radiculares o meníngeas a cualquier nivel de la médula espinal. Las consecuencias personales, familiares, sociales y económicas de esta enfermedad, hacen que sea un tema relevante en la actualidad. El propósito de esta revisión es entregar al lector las herramientas elementales sobre el TRM, y está principalmente enfocada en el tratamiento, el cual se aborda estrechamente relacionado con la fisiopatología para comprender los mecanismos moleculares y biomecánicos de trauma, incluyendo sus complicaciones y el manejo de éstas. Respecto al tratamiento del TRM, se aborda la evidencia que ofrecen las terapias actualmente validadas y las aún controversiales, incluyendo los glucocorticoides, la reducción cerrada y la cirugía precoz. Además las terapias emergentes como la hipotermia terapéutica, los nuevos agentes neuroprotectores que se encuentran en fases preclínicas y clínicas de estudio como el riluzol, la minociclina, el litio, los antagonistas opioides, entre otros, y los agentes neurorregenerativos como el Cethrin y el Anti-Nogo que han mostrado buenos resultados en la recuperación neurológica. Las recomendaciones actuales respecto a la terapia con células madre y subtipos de células madre en la actualidad, es que deben llevarse a cabo sólo en el contexto de ensayos clínicos. Aunque aún no existen terapias que permitan la recuperación neurológica completa en todos o la mayoría de los pacientes, las terapias emergentes prevén un futuro promisorio en los resultados clínicos de los pacientes con TRM.


The traumatic spinal cord injury (TSCI) involves all traumatic injuries that harm the bones, ligaments, muscles, cartilage, vascular, radicular or meningeal structures, at any level of the spinal cord. The personal, family, social and economic consequences of this disease, make it an important issue today. The purpose of this review is to provide the reader, the basic tools of the TRM, and it is mainly aimed at the treatment, which it approaches closely related to the pathophysiology, to understand the molecular and biomechanical mechanisms of trauma, including its complications and his management. Regarding treatment of TSCI, the evidence offered by currently validated and controversial therapies is discussed, including glucocorticoids, closed reduction and early surgery. Also emerging therapies such as therapeutic hypothermia, new neuroprotective agents currently in preclinical and clinical phases as riluzole, minocycline, lithium, opioid antagonists, among others, and neuroregenerative agents like Cethrin and Anti- Nogo that have shown good results in neurological recovery. Current recommendations for therapy with stem cells and subtype stem cell, is that only should be carried out in the context of clinical trials. Although there are not still therapies that allow full neurological recovery in all or most patients, emerging therapies provide a promising future in the clinical outcomes of patients with TRM.


Subject(s)
Humans , Spinal Canal/physiopathology , Spinal Canal/injuries , Neuroprotective Agents/pharmacology , Hypothermia, Induced/methods , Spinal Cord Regeneration , Stem Cell Transplantation , Multiple Trauma/epidemiology , Spinal Cord Injuries/complications , Spinal Cord Injuries/therapy , Glucocorticoids/administration & dosage , Prognosis , Closed Fracture Reduction/methods
16.
Arq. neuropsiquiatr ; 74(9): 730-736, Sept. 2016. tab, graf
Article in English | LILACS | ID: lil-796044

ABSTRACT

ABSTRACT Propentofylline is a xanthine derivative that depresses activation of glial cells, whose responses contribute to neural tissue damage during inflammation. Ethidium bromide injection into the central nervous system induces local oligodendroglial and astrocytic loss, resulting in primary demyelination, neuroinflammation and blood-brain barrier disruption. Surviving astrocytes present a vigorous reaction around the injury site with increased immunoreactivity to glial fibrillary acidic protein (GFAP). Objective This study aimed to evaluate the effect of propentofylline administration on astrocytic response following gliotoxic injury. Method Wistar rats were injected with ethidium bromide into the cisterna pontis and treated or not with propentofylline (12.5mg/kg/day, intraperitoneal) during the experimental period. Brainstem sections were collected from 15 to 31 days after gliotoxic injection and processed for GFAP immunohistochemistry. Results and Conclusion Results demonstrate that propentofylline decreased astrocytic activation until the 21st day, suggesting that this drug may have a role in reducing glial scar development following injury.


RESUMO A propentofilina é uma xantina que deprime a ativação das células gliais, cujas respostas contribuem para o dano neural durante inflamação. A injeção de brometo de etídio no sistema nervoso central induz a perda oligodendroglial e astrocitária, resultando em desmielinização, neuroinflamação e ruptura da barreira hematoencefálica. Os astrócitos sobreviventes apresentam vigorosa reação ao redor da lesão com aumento da imunorreatividade à proteína glial fibrilar ácida (GFAP). Objetivo Este estudo objetivou avaliar o efeito da propentofilina sobre a resposta astrocitária após injúria gliotóxica. Método Ratos Wistar foram injetados com brometo de etídio na cisterna basal e tratados ou não com propentofilina (12.5mg/kg/dia, intraperitoneal). Amostras do tronco encefálico foram coletadas dos 15 aos 31 dias pós-injeção do gliotóxico e processadas para estudo ultraestrutural e imuno-histoquímico para GFAP. Resultados e Conclusão Os resultados demonstram que a propentofilina reduziu a ativação astrocitária até o 21o dia, sugerindo que essa droga pode atuar na redução da cicatriz glial após injúria.


Subject(s)
Animals , Male , Xanthines/pharmacology , Brain Stem/drug effects , Astrocytes/drug effects , Neuroprotective Agents/pharmacology , Time Factors , Brain Stem/metabolism , Immunohistochemistry , Astrocytes/metabolism , Reproducibility of Results , Demyelinating Diseases/metabolism , Demyelinating Diseases/prevention & control , Treatment Outcome , Rats, Wistar , Disease Models, Animal , Ethidium/toxicity , Glial Fibrillary Acidic Protein/analysis , Glial Fibrillary Acidic Protein/drug effects , Gliotoxin/toxicity
17.
Clinics ; 71(6): 351-360, tab, graf
Article in English | LILACS | ID: lil-787429

ABSTRACT

OBJECTIVE: To evaluate the functional and histological effects of ganglioside G(M1) and erythropoietin after experimental spinal cord contusion injury. METHODS: Fifty male Wistar rats underwent experimental spinal cord lesioning using an NYU-Impactor device and were randomly divided into the following groups, which received treatment intraperitoneally. The G(M1) group received ganglioside G(M1) (30 mg/kg); the erythropoietin group received erythropoietin (1000 IU/kg); the combined group received both drugs; and the saline group received saline (0.9%) as a control. A fifth group was the laminectomy group, in which the animals were subjected to laminectomy alone, without spinal lesioning or treatment. The animals were evaluated according to the Basso, Beattie and Bresnahan (BBB) scale, motor evoked potential recordings and, after euthanasia, histological analysis of spinal cord tissue. RESULTS: The erythropoietin group had higher BBB scores than the G(M1) group. The combined group had the highest BBB scores, and the saline group had the lowest BBB scores. No significant difference in latency was observed between the three groups that underwent spinal cord lesioning and intervention. However, the combined group showed a significantly higher signal amplitude than the other treatment groups or the saline group (p<0.01). Histological tissue analysis showed no significant difference between the groups. Axonal index was significantly enhanced in the combined group than any other intervention (p<0.01). CONCLUSION: G(M1) and erythropoietin exert therapeutic effects on axonal regeneration and electrophysiological and motor functions in rats subjected to experimental spinal cord lesioning and administering these two substances in combination potentiates their effects.


Subject(s)
Animals , Male , Erythropoietin/pharmacology , G(M1) Ganglioside/pharmacology , Neuroprotective Agents/pharmacology , Recovery of Function/drug effects , Spinal Cord Injuries/drug therapy , Drug Therapy, Combination , Erythropoietin/therapeutic use , G(M1) Ganglioside/therapeutic use , Injections, Intraperitoneal , Locomotion/drug effects , Models, Animal , Necrosis , Random Allocation , Rats, Wistar , Reaction Time/drug effects , Spinal Cord Injuries/pathology , Spinal Cord Injuries/physiopathology
18.
Braz. j. med. biol. res ; 49(2): e4543, 2016. graf
Article in English | LILACS | ID: biblio-951657

ABSTRACT

High plasma levels of homocysteine (Hcy) promote the progression of neurodegenerative diseases. However, the mechanism by which Hcy mediates neurotoxicity has not been elucidated. We observed that upon incubation with Hcy, the viability of a neuroblastoma cell line Neuro2a declined in a dose-dependent manner, and apoptosis was induced within 48 h. The median effective concentration (EC50) of Hcy was approximately 5 mM. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) nuclear translocation and acylation has been implicated in the regulation of apoptosis. We found that nuclear translocation and acetylation of GAPDH increased in the presence of 5 mM Hcy and that higher levels of acetyltransferase p300/CBP were detected in Neuro2a cells. These findings implicate the involvement of GAPDH in the mechanism whereby Hcy induces apoptosis in neurons. This study highlights a potentially important pathway in neurodegenerative disorders, and a novel target pathway for neuroprotective therapy.


Subject(s)
Animals , Rabbits , Apoptosis/drug effects , Neuroprotective Agents/pharmacology , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Homocysteine/pharmacology , Acetylation , Acetyltransferases/analysis , Time Factors , Cell Count , Cell Extracts/chemistry , Cell Nucleus/metabolism , Cell Survival/physiology , Enzyme Induction , Blotting, Western , Fluorescent Antibody Technique , Apoptosis/physiology , Neuroprotective Agents/administration & dosage , Cell Line, Tumor , p300-CBP Transcription Factors/metabolism , Homocysteine/administration & dosage
19.
Arq. neuropsiquiatr ; 73(9): 784-790, Sept. 2015. ilus
Article in English | LILACS | ID: lil-757393

ABSTRACT

Inflammation and oxidative stress have important roles in memory impairment. The effect of 7-nitroindazole (7NI) on lipopolysaccharide (LPS)-induced memory impairment was investigated. Rats were used, divided into four groups that were treated as follows: (1) control (saline); (2) LPS; (3) 7NI-LPS; and (4) 7NI before passive avoidance (PA). In the LPS group, the latency for entering the dark compartment was shorter than in the controls (p < 0.01 and p < 0.001); while in the 7NI-LPS group, it was longer than in the LPS group (p < 0.01 and p < 0.001). Malondialdehyde (MDA) and nitric oxide (NO) metabolite concentrations in the brain tissues of the LPS group were higher than in the controls (p < 0.001 and p < 0.05); while in the 7NI-LPS group, they were lower than in the LPS group (p < 0.001 and p < 0.05, respectively). The thiol content in the brain of the LPS group was lower than in the controls (p < 0.001); while in the 7NI-LPS group, it was higher than in the LPS group (p < 0.001). It is suggested that brain tissue oxidative damage and NO elevation have a role in the deleterious effects of LPS on memory retention that are preventable using 7NI.


Inflamação e estresse oxidativo tem importante papel no déficit de memória. O efeito do 7-nitroindazol (7NI) no déficit de memória induzido por lipossacarídeos (LPS) foi investigado. Foram utilizados ratos que foram divididos em quatro grupos e tratados da seguinte maneira: (1) controles (solução salina); (2) LPS; (3) 7NI-LPS; e (4) 7NI antes da esquiva passiva (PA). No grupo LPS, a latência para entrar no compartimento escuro foi mais curta que nos controles (p < 0,01 e p < 0,001); enquanto no grupo 7NI-LPS, a latência foi maior que aquela do grupo LPS (p < 0,01 e p < 0,001). Concentrações de malondialdeído (MDA) e metabólitos do ácido nítrico (NO) no tecido cerebral do grupo LPS foram maiores que aquelas dos controles (p < 0,001 e p < 0,05); enquanto no grupo 7NI-LPS, as concentrações foram menores do que no grupo LPS (p < 0,001 e p < 0,05, respectivamente). O conteúdo cerebral de tiol no grupo LPS foi menos do que nos controles (p < 0,001); enquanto no grupo 7NI-LPS, este conteúdo foi maior que no grupo LPS (p < 0,001). Sugere-se que o dano oxidativo cerebral e o aumento de NO tenham um papel nos efeitos deteriorativos dos LPS na memória de retenção, e que isto possa ser prevenido com o uso de 7NI.


Subject(s)
Animals , Male , Rats , Indazoles/pharmacology , Lipopolysaccharides/toxicity , Memory Disorders/prevention & control , Memory/drug effects , Neuroprotective Agents/pharmacology , Brain Chemistry , Memory Disorders/chemically induced , Rats, Wistar
20.
Acta cir. bras ; 30(6): 394-400, 06/2015. tab, graf
Article in English | LILACS | ID: lil-749642

ABSTRACT

PURPOSE: To evaluate the central nervous system toxicity of cisplatin and neuroprotective effect of selenium. METHODS: Twenty-one male Wistar albino rats were divided into three groups: control (C), cisplatin (CS), cisplatin and selenium (CSE, n=7 in each group). Cisplatin (12 mg/kg/day, i.p.) was administered to CS and CSE groups for three days. Furthermore, CSE group received 3mg/kg/day (twice-a-day as 1.5 mg/kg) selenium via oral gavage five days before cisplatin injection and continued for 11 consecutive days. The same volumes of saline were administered to C group intraperitoneally and orally at same time. RESULTS: Heterochromatic and vacuolated neurons and dilated capillary vessels in the brain were observed in the histochemical examinations of cisplatin treated group. Rats that were given a dose of 3mg/kg/day selenium decreased the cisplatin induced histopathological changes in the brain, indicating a protective effect. In addition, cytoplasmic staining of the cell for bcl-2, both cytoplasmic and nuclear staining for bax were determined to be positive in the all groups. Bax positive cells were increased in the CS group compared to C group, in contrast to decreased bcl-2 positivity. CONCLUSION: Selenium limited apototic activity and histological changes due to the cisplatin related central neurotoxicity. .


Subject(s)
Animals , Male , Antineoplastic Agents/toxicity , Antioxidants/pharmacology , Brain/drug effects , Cisplatin/toxicity , Neurons/drug effects , Selenium/pharmacology , Apoptosis/drug effects , Brain/pathology , Immunohistochemistry , Models, Animal , Neuroprotective Agents/pharmacology , Rats, Wistar , Reproducibility of Results , Time Factors
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