RESUMO
BACKGROUND: Cerebral infarction occurs when the arteries to brain are obstructed, and motor impairment contralateral to responsible lesion is commonly recognized. Few studies have profiled the characteristics of cases with ipsilateral motor impairment. We sought to characterize clinical features of patients with motor dysfunction caused by ipsilateral ischemic stroke. METHODS: We retrieved and analyzed the medical data for patients with ipsilateral cerebral infarction. Patients were regarded as having ipsilateral cerebral infarction if motor impairment is ipsilateral to recent stroke lesions. RESULTS: Only 22 patients with unusual ipsilateral cerebral infarction were included in this study. Ipsilateral limb paralysis was observed in all cases, and one case showed central facioplegia. Majority of patients with limb paralysis (90.9%, 20/22) presented with mild muscle strength deficits (MRC grading of 4 or more). Most of the patients (72.7%, 16/22) had a past history of stroke, and previous strokes were contralateral to the side of the recent stroke in 14 out of 16 patients (87.5%). No history of stroke or cerebral injury was identified in seven patients. With aspect of MRI findings, recent infarct lesions of all cases were located along the corticospinal tract. CONCLUSIONS: History of stroke plays an important role in the pathogenesis of ipsilateral motor impairment, and cortical reorganization in the unaffected hemisphere may contribute to the compensation of motor function after stroke. Besides that, some cases with first stroke may be due to impairment of ipsilateral uncrossed corticospinal fibers.
Assuntos
Infarto Cerebral/complicações , Infarto Cerebral/patologia , Lateralidade Funcional/fisiologia , Paralisia/etiologia , Paralisia/fisiopatologia , Adulto , Idoso , Infarto Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Transtornos Motores/etiologia , Transtornos Motores/fisiopatologia , Neuroimagem , Paralisia/diagnóstico por imagem , Acidente Vascular Cerebral/complicaçõesRESUMO
PURPOSE: Reflex epilepsy is a type of epilepsy with seizures that are consistently triggered by a specific stimulus. Zipai is a Chinese ancient card game which has been popular in Southern China for hundreds of years. We sought to report and characterize clinical features of patients with reflex epilepsy evoked by playing Zipai. METHODS: We collected and analyzed clinical data of patients with Zipai-induced epilepsy. Patients were regarded as having Zipai-induced epilepsy if they suffered at least two seizure attack during the course of playing Zipai. Prolonged electroencephalography (EEG) and brain magnetic resonance imaging (MRI) were applied to all patients. All patients were advised to avoid watching and playing Zipai games in daily life, instead of using antiepileptic drugs. The seizure outcome was assessed during outpatient visits and by telephone contact. RESULTS: Five patients were included in this study. No spontaneous seizures occurred in all five patients. No patients had experienced myoclonic and coexistent absences with generalized tonic-clonic seizures (GTCS). All patients had normal MRI and prolonged EEG findings. All patients were advised to avoid the Zipai game, and became seizure-free without medication during the follow-up period (mean 5.4â¯years, range 3.5-7â¯years). CONCLUSION: Zipai-induced epilepsy may be an unreported subtype form of reflex epilepsy with praxis induction. Nonpharmacological conservative treatment plays a significant role in the treatment of reflex epilepsy.
Assuntos
Aprendizagem da Esquiva , Epilepsia Reflexa/diagnóstico por imagem , Epilepsia Reflexa/prevenção & controle , Jogos Recreativos , Adulto , Anticonvulsivantes/uso terapêutico , Aprendizagem da Esquiva/fisiologia , China , Eletroencefalografia/tendências , Epilepsia Reflexa/psicologia , Seguimentos , Jogos Recreativos/psicologia , Humanos , Imageamento por Ressonância Magnética/tendências , Masculino , Convulsões/diagnóstico por imagem , Convulsões/prevenção & controle , Convulsões/psicologia , Resultado do Tratamento , Adulto JovemRESUMO
CD4+ T cells and many cytokines play critical roles in the pathogenesis of Guillain-Barré Syndrome (GBS), an immune-mediated inflammatory disease. However, the role of IL-35, a novel member of the IL-12 cytokine family, in this kind of disease has not yet been elucidated. In this study, we investigated the functional changes of CD4+ T cells from GBS patients with IL-35 treatment in vitro. This study involved 21 GBS patients and an equal number of healthy controls (HCs). The results indicated that the average concentration of IL-35 in the plasma of GBS patients was lower than that of healthy controls (HCs). Increased levels of STAT1, STAT3 and STAT4 proteins and T-bet, ROR γt, IFN-γ and IL-17A mRNA were observed in CD4+ T cells from GBS patients. In contrast, the levels of STAT5 and STAT6 proteins and GATA3, Foxp3, IL-4 and TGF-ß1 mRNAs were decreased in GBS patients in comparison with those of HCs. In addition, treatment of CD4+ T cells from GBS patients with IL-35 upregulated IL-35, STAT5 and STAT6 protein and T-bet, GATA3, Foxp3, IFN-γ, IL-4, IL-17A and TGF-ß1 mRNA while inhibited levels of STAT3 and STAT4 protein and RORγt and IL-17A mRNA. These results indicate that IL-35 might play a potential role in GBS pathogenesis. Further studies are required in order to evaluate its role in GBS.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Citocinas/imunologia , Síndrome de Guillain-Barré/imunologia , Adulto , Citocinas/sangue , Feminino , Síndrome de Guillain-Barré/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Adulto JovemRESUMO
BACKGROUND: Epilepsy is one of the most common neurological disorders, and approximately one-third of patients with epilepsy are resistant to anti-epileptic drugs (AEDs). Recent emerging evidence has demonstrated the roles of innate immunity and the associated inflammatory processes in epilepsy. Toll-like receptors (TLRs) are a type of pattern-recognition receptor that promote innate immune defense. The SOCS proteins as negative-feedback regulators in cytokine signaling are involved in the regulation of TLR-mediated immune responses. However, few studies investigating the role of TLRs and SOCSs in epilepsy have been reported. METHODS: To explore the role of innate immunity in the mechanism of epilepsy, the pentylenetetrazole (PTZ) kindling rat model was established using intraperitoneal injection of PTZ. The expression levels of TLR2, TLR4, and STAT molecules in rat hippocampi were analyzed using qRT-PCR and western blotting techniques. The expression levels of SOCS-1 and SOCS-3 in rat hippocampi were analyzed using qRT-PCR. RESULTS: Our data demonstrated that both the mRNA and protein expression of TLR2 and TLR4 were significantly upregulated in the rat hippocampus with PTZ injection, which was accompanied by an inhibition of SOCS-1 and SOCS-3 and an upregulation of STAT3. CONCLUSIONS: Our study suggested that SOCSs and TLRs contribute to the development of epilepsy which may lead to therapeutic interventions that limit epileptogenesis.
Assuntos
Epilepsia/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Excitação Neurológica , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Receptores Toll-Like/metabolismo , Animais , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Epilepsia/patologia , Epilepsia/fisiopatologia , Interleucina-1beta/metabolismo , Masculino , Pentilenotetrazol , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição STAT/metabolismo , Proteínas Supressoras da Sinalização de Citocina/genética , Receptores Toll-Like/genética , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genéticaRESUMO
Epilepsy is a brain disorder, which is characterized by a predisposition to generate seizures that are associated with neurobiological, psychological cognitive and linguistic problems. Current treatments of epilepsy remain difficult, and antiepileptic drugs fail for some patients. Expressions of different microRNAs (miRNAs) in different brain regions are implicated in epileptogenic activity. MiRNAs are important regulators of seizure-induced neuronal death. The activation of inflammatory pathways is involved in reactive astrocytes and cells of the microglia in human temporal lobe epilepsy (TLE). MiRNAs are regulators of the innate immune response in the modulation of astrocyte-mediated inflammation. These miRNAs can possibly be used as a novel therapeutic target in the treatment of TLE. Targeting miRNA in epilepsy supports it as a feasible strategy for the treatment of epilepsy. But this powerful technique has received less attention as a potential therapeutic strategy. This is mainly because of the lack of well-defined targets in epilepsy. This review focuses on the role of miRNA in epilepsy, and recent advances in miRNA targeted epileptic therapies.
Assuntos
Epilepsia/genética , Epilepsia/terapia , MicroRNAs/uso terapêutico , Animais , Citocinas/metabolismo , Regulação da Expressão Gênica/genética , Humanos , Mediadores da Inflamação/uso terapêutico , MicroRNAs/genéticaRESUMO
Background: An increasing number of observational studies have suggested an association between dental caries and Alzheimer's disease (AD). The association between dental caries and Alzheimer's disease may be mediated by confounders or reverse causality. In this study, we conducted bidirectional two-sample Mendelian randomization (MR) to estimate the bidirectional causality between dental caries and AD. Materials and Methods: Genome-wide association study (GWAS) summary statistics of dental caries were extracted from a published meta-analysis which included a total of 487,823 participants. GWAS datasets of AD and AD onset age were obtained from the FinnGen bank. A bidirectional two-sample analysis was performed to explore the causality between dental caries and AD. Results: For the dental caries-AD causality estimation, there was no significant association between dental caries and AD, neither with the AD GWASs from the FinnGen database (OR: 1.041, p = 0.874) nor with those from the International Genomics of Alzheimer's Project (OR: 1.162, p = 0.409). In addition, the genetic susceptibility to dental caries was not related to the onset age of AD. No causality existed between dental caries and early-onset AD (OR: 0.515, p = 0.302) or late-onset AD (OR: 1.329, p = 0.347). For the AD-dental caries relationship, no causality was detected by the IVW method (OR: 1.000, p = 0.717). Findings from other MR methods were consistent. The pleiotropy test and sensitivity analysis confirmed the validity of these MR results. Conclusions: In this bidirectional MR study, robust evidence to support a bidirectional causal effect between dental caries and AD from the GWAS results within large-scale European-descent populations was absent. Having dental caries would not alter the onset age of AD.
Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/epidemiologia , Causalidade , Estudo de Associação Genômica Ampla , Análise da Randomização MendelianaRESUMO
OBJECTIVE: A myriad of transcription factors and inflammatory cytokines have been described to participate in the pathogenesis of Guillain-Barré syndrome (GBS). However, the innate immunity components--Toll-like receptors (TLRs)--have never been explored in this disease. We therefore investigated the expression of TLR2, 4 and 9 in the peripheral circulation of GBS patients as well as healthy controls. METHODS: Twenty-one GBS patients and 21 healthy donors participated in this study. Peripheral blood mononuclear cells were used for mRNA and protein analysis of TLR-related molecules. Also, peripheral blood mononuclear cells from different subjects were incubated with different TLR agonists and the subsequent IFN-γ secretion was determined. RESULTS: Expression of TLR2, 4 and 9 as well as their related signaling molecules were higher in GBS patients compared to healthy controls. Disability scores of GBS patients had a strong positive correlation with the high levels of expression of TLR2, 4 and 9. CONCLUSIONS: The TLR signaling pathway may be involved in the pathogenesis of GBS.
Assuntos
Regulação da Expressão Gênica/fisiologia , Síndrome de Guillain-Barré/patologia , Leucócitos Mononucleares/metabolismo , Receptores Toll-Like/metabolismo , Adulto , Citocinas/metabolismo , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Síndrome de Guillain-Barré/imunologia , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Estatística como Assunto , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Adulto JovemRESUMO
Susceptible-strain animals immunized with P2 peptide could generate the disease of experimental autoimmune neuritis (EAN) with inflammation and demyelination of peripheral nerve. A myriad of transcription factors and inflammatory cytokines have been found to participate in this process; however, the roles of toll-like receptors (TLRs) are poorly understood in EAN. The aim of this study is to explore the role of TLR9 in the pathogenesis of EAN. The EAN was induced in Lewis rat by immunization with P2(53-78) and complete Freund's adjuvant. CpG oligodeoxynucleotides (ODN) (cODN), a suppressive ODN (sODN) and a control non-specific ODN (nODN) were respectively administered to explore the role of TLR9 in EAN both in vivo and vitro. Following immunization up to the peak phase of EAN, EAN rats inoculated with sODN had remarkably better clinical score of EAN and expressed a significantly inhibited TLR9 signaling pathway. Our study suggests that TLR9 may be involved in the pathogenesis of EAN.
Assuntos
Síndrome de Guillain-Barré/imunologia , Neurite Autoimune Experimental/imunologia , Oligodesoxirribonucleotídeos Antissenso/administração & dosagem , Receptor Toll-Like 9/metabolismo , Animais , Modelos Animais de Doenças , Progressão da Doença , Suscetibilidade a Doenças , Adjuvante de Freund/administração & dosagem , Síndrome de Guillain-Barré/terapia , Humanos , Imunização , Masculino , Proteína P2 de Mielina/administração & dosagem , Neurite Autoimune Experimental/induzido quimicamente , Neurite Autoimune Experimental/genética , Neurite Autoimune Experimental/fisiopatologia , Neurite Autoimune Experimental/terapia , Oligodesoxirribonucleotídeos Antissenso/efeitos adversos , Fragmentos de Peptídeos/administração & dosagem , Ratos , Ratos Endogâmicos Lew , Receptor Toll-Like 9/genéticaRESUMO
Objectives: Multiple sclerosis (MS) is a chronic inflammatory autoimmune and degenerative disorder of the central nervous system. Telomeres are protective structures located at the ends of linear chromosomes, and leukocyte telomere length (LTL) is closely connected with cell aging and senescence. However, the relationship between LTL and the risk of MS remains unknown. Methods: We performed a two-sample Mendelian randomization (MR) to evaluate whether LTL was causally associated with MS risk. Results: In our MR analysis, 12 LTL-related variants were selected as valid instrumental variables, and a causal relationship between LTL and MS was suggested. The risk of MS nearly doubled as the genetically predicted LTL shortened by one standard deviation (SD) under the inverse variance weighted (IVW) fixed effect model (odds ratio (OR) = 2.00, 95% confidence interval (CI): 1.52-2.62, p = 6.01e-07). Similar estimated causal effects were also observed under different MR models. The MR-Egger regression test did not reveal any evidence of directional pleiotropy (intercept = -0.005, stand error (SE) = 0.03, p = 0.87). The Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO) analysis also indicated no directional pleiotropy or outliers for any LTL-related IVs (p-global test = 0.13). In addition, a leave-one-out sensitivity analysis showed similar findings, which further emphasized the validity and stability of the causal relationship. Conclusions: Our results suggest a potential causal effect of LTL on the risk of MS. Genetically predicted shorter LTL could increase the risk of MS in the European population. LTL should be noted and emphasized in the pathogenesis and treatment of MS.
Assuntos
Análise da Randomização Mendeliana , Esclerose Múltipla , Estudo de Associação Genômica Ampla , Humanos , Leucócitos , Esclerose Múltipla/genética , Polimorfismo de Nucleotídeo Único , Telômero/genéticaRESUMO
OBJECTIVE: To observe the expression of cyclin-dependent kinase 5 (Cdk5), p35, tau protein and the activity of Cdk5 in rat hippocampus during pentylenetetrazole (PTZ) kindling process and their correlation with mossy fiber sprouting (MFS) so as to investigate the role of Cdk5/p35 in epileptogenesis. METHODS: A total of 240 healthy male SD rats were divided randomly into normal controls and pentylenetetrazole (PTZ) treatment groups. The epileptic models were established by injection of PTZ intraperitoneally. At Day 3, Weeks 1, 2, 4 & 6 after a daily injection of PTZ, Timm staining was scored in the CA3 region and dentate gyrus. At the same time, the mRNA and protein of Cdk5 and p35, total tau protein and its phosphorylation at ser202 and Cdk5 activity were analyzed in the hilus and stratum granulosum of dentate gyrus and the CA1, CA3 regions of hippocampus. The methods of in situ hybridization, immunohistochemistry, Western blot and immuno-precipitation and liquid scintillation counter were employed respectively. RESULTS: Prominent MFS was observed in area CA3 rather than the inner molecular layer in PTZ-treated rats. And the degree of MFS progressed with the development of behavioral kindled seizures. The expressions of Cdk5/p35 mRNA and protein, tau protein and its phosphorylation at Ser202 significantly increased from Day 3 to Week 4 in the PTZ treatment group. It was in accordance with the progression of MFS in area CA3. CONCLUSION: Cdk5/p35 and its substrate tau protein may be involved in MFS. Understanding the molecular mechanisms of MFS may lead to therapeutic interventions for limiting epileptogenesis.
Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Excitação Neurológica/metabolismo , Fibras Musgosas Hipocampais/metabolismo , Pentilenotetrazol/efeitos adversos , Proteínas tau/metabolismo , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: The most well-documented synaptic reorganization associated with temporal lobe epilepsy is mossy fiber sprouting (MFS), which is believed to play a critical role in epileptogenesis. However, the molecular mechanisms underlying this phenomenon remain unclear. Cyclin-dependent kinase 5 (Cdk5) is a proline-directed serine/threonine kinase which is found to be crucial in axon growth and synaptic plasticity. We hypothesized that Cdk5 contributed to MFS via phosphorylating its substrate tau protein, which was known to facilitate microtubule stabilization and axonal elongation. METHODS: 240 male SD rats were randomly divided into the control group and PTZ group. The epileptic models were established by intraperitoneal PTZ injection, while the control rats were injected with an equal dose of saline. At different time points, Cdk5/p35 mRNA and protein, total tau protein and its phosphorylation at Ser202 (p-tau) and Cdk5 activity were analyzed in different regions of hippocampus by in situ hybridization, immunohistochemistry, Western blot, immuno-precipitation and liquid scintillation counter. Hippocampus was also evaluated for MFS with Timm stain. RESULTS: Prominent MFS was observed in area CA3 rather than the inner molecular layer in PTZ treated rats and the degree of MFS progressed with the development of behavioral kindled seizures. The expression of Cdk5/p35 mRNA and protein, tau protein and its phosphorylation at Ser202 significantly increased from 3 days to 4 weeks in the PTZ group, which was in accordance with the progression of MFS in area CA3. CONCLUSIONS: Cdk5/p35 and its substrate tau protein may be involved in MFS. Understanding the molecular mechanisms underlying MFS may lead to therapeutic interventions that limit epileptogenesis.
Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Hipocampo/metabolismo , Fibras Nervosas/fisiologia , Pentilenotetrazol/farmacologia , Proteínas tau/metabolismo , Animais , Quinase 5 Dependente de Ciclina/genética , Progressão da Doença , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/fisiopatologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Imuno-Histoquímica , Hibridização In Situ , Injeções Intraperitoneais , Excitação Neurológica/fisiologia , Masculino , Fibras Nervosas/efeitos dos fármacos , Pentilenotetrazol/administração & dosagem , Ratos , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/metabolismoRESUMO
AIM: The aim of this study was to determine the correlations among hippocampal damage, spontaneous recurrent seizures (SRS), and mossy fiber sprouting (MFS) using pentylenetetrazole (PTZ) kindling model. METHODS: Chronic epileptic model was established by administration of PTZ. Behaviour and EEG seizure activity were recorded. Rats' hippocampus were analyzed with haematoxylin and eosin (H&E) stain for histological lesions and evaluated for MFS with Timm stain. RESULTS: Prominent MFS was observed in area CA3 rather than the inner molecular layer in PTZ treated rats and the degree of MFS progressed with the development of behavioral kindled seizures. MFS preceded the occurrence of spontaneous seizures. No obvious neuronal necrosis and loss were observed in different regions of the hippocampus during kindling progression. CONCLUSION: MFS is not the outcome of SRS. Severe hippocampal damage is not required in the development of MFS and SRS.
Assuntos
Hipocampo/patologia , Excitação Neurológica/patologia , Fibras Musgosas Hipocampais/patologia , Convulsões/patologia , Animais , Eletroencefalografia , Hipocampo/fisiopatologia , Masculino , Fibras Musgosas Hipocampais/fisiopatologia , Neurônios/patologia , Pentilenotetrazol/toxicidade , Ratos , Ratos Sprague-Dawley , Convulsões/fisiopatologia , Coloração e Rotulagem , Estatísticas não ParamétricasRESUMO
The aim of this study was to investigate the changes of expression of Fas-associated proteins and its cellular localization in the peri-infarct region following transient focal cerebral ischemia. Adult male Sprague-Dawley rats underwent right middle cerebral artery occlusion (MCAo) for 2 h and reperfusion for 1, 3, 6, 12 and 24 h. The expression of Fas-associated death domain protein (FADD), Fas-associated phosphatase-1 (FAP-1) caspase-8 and death-associated protein (Daxx), the pro-apoptotic genes, were examined by methods of RT-PCR, immunohistochemistry and Western blot. The results showed that the expression levels of mRNA and protein for FADD and caspase-8 increased significantly at 1-3 h after reperfusion, peaked at 12 h, then declined markedly at 24 h. The time course change of FAP-1 was consistent with that of FADD. The expression level of mRNA and protein for death-associated protein (Daxx) increased significantly at 3 h after reperfusion and persisted for 24 h at a high level. Immunofluorescence double-staining laser scanning showed that the immunoreactivity of FADD was localized in cytoplasm, and Daxx immunoreactivity was translocated from nucleus to cytoplasm at 3 h after reperfusion. The TUNEL-positive cells could be found in peri-infarct region at 3 h and increased with time after reperfusion. Our findings suggest a possible association between expression of FADD, caspase-8, Daxx and FAP-1 genes and apoptosis following ischemia.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Isquemia Encefálica/metabolismo , Proteína de Domínio de Morte Associada a Fas/metabolismo , Proteínas Nucleares/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 13/metabolismo , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose/genética , Apoptose/fisiologia , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismo , Isquemia Encefálica/complicações , Caspase 8/genética , Caspase 8/metabolismo , Proteína de Domínio de Morte Associada a Fas/genética , Imuno-Histoquímica , Masculino , Chaperonas Moleculares , Proteínas Nucleares/genética , Proteína Tirosina Fosfatase não Receptora Tipo 13/genética , RNA Mensageiro/análise , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Distribuição TecidualRESUMO
OBJECTIVE: To observe the expression of cyclin-dependent kinase 5 (Cdk5) and p35 in rat hippocampus during pentetrazole kindling process and their relation with mossy fiber sprouting (MFS), and to investigate the role of Cdk5/p35 in epileptogenesis. METHODS: Altogether 120 healthy male SD rats were randomly divided into a control group and a pentylenetetrazole (PTZ) treated group. The epileptic models were established by the injection of PTZ intraperitoneally while the control rats were injected with an equal dose of saline. At the 3rd day, 1st week, 2nd week, 4th week, and 6th week after daily injection, Timm staining was performed in area CA3 and dentate gyrus, and the mRNA and protein of Cdk5 and p35 were analyzed in the hilus and stratum granulosum of dentate gyrus and area CA1 and CA3 of hippocampus, by in situ hybridization and immunohistochemistry, respectively. RESULTS: The expression levels of Cdk5 and p35 mRNA were significantly higher in the PTZ treated subgroups of the 3rd day, 1st week, 2nd week, and 4th week than those in the controls. Thereafter, the expression decreased to the level of controls. The expression level of Cdk5 and p35 protein increased from the 3rd day to 2nd week, and then gradually decreased to the level of the controls. Timm scores for PTZ groups were 1 to approximately 4 before kindling and 4~5 after kindling in area CA3. CONCLUSION: Change of Cdk5/p35 expression in the hippocampus may play a role in epileptogenesis by influencing the process of mossy fiber sprouting.
Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Epilepsia/metabolismo , Excitação Neurológica/metabolismo , Fibras Musgosas Hipocampais/metabolismo , Pentilenotetrazol/toxicidade , Fosfotransferases/metabolismo , Animais , Quinase 5 Dependente de Ciclina/genética , Epilepsia/induzido quimicamente , Excitação Neurológica/efeitos dos fármacos , Masculino , Fosfotransferases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Aleatória , Ratos , Ratos Sprague-DawleyRESUMO
OBJECTIVE: To determine the changes of mossy fiber sprouting in hippocampus of pre-kindling and post-kindling rats of chronic epilepsy induced by pentylenetetrazole (PTZ). METHODS: Sixty rats were randomly divided into a control group and a PTZ group (PTZ 30 mg/kg, intraperitoneal injection, once daily). The changes of mossy fiber sprouting in hippocampus of pre-kindling and post-kindling rats were examined by Timm staining. RESULTS: Before the occurrence of convulsion confirmed by behavior and EEG, the mossy fiber sprouting was found in the PTZ group. The grade of the mossy fiber sprouting increased with the gradual establishment of kindling effect. CONCLUSION: Mossy fiber sprouting may play an important role in the onset and development of epilepsy.
Assuntos
Epilepsia/patologia , Excitação Neurológica/efeitos dos fármacos , Fibras Musgosas Hipocampais/crescimento & desenvolvimento , Pentilenotetrazol/farmacologia , Animais , Modelos Animais de Doenças , Epilepsia/induzido quimicamente , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-DawleyRESUMO
Mossy fiber sprouting (MFS) is a unique feature of chronic epilepsy. However, the molecular signals underlying MFS are still unclear. The repulsive guidance molecule A (RGMa) appears to contribute to axon growth and axonal guidance, and may exert its biological effects by dephosphorylating focal adhesion kinase (FAK) at Tyr397, then regulating the activation of Ras. The objective of this study was to explore the expression patterns of RGMa, FAK (Tyr397) and Ras in epileptogenesis, and their correlation with MFS. The epileptic models were established by intraperitoneal pentylenetetrazole (PTZ) injection of SpragueDawley rats. At 3 days and at 1, 2, 4 and 6 weeks after the first PTZ injection, Timm staining was scored at different time points in the CA3 region of the hippocampus and dentate gyrus. The protein levels of RGMa, FAK (Tyr397) and Ras were analyzed at different time points in the CA3 region of the hippocampus using immunofluorescence, immunohistochemistry and western blot analysis. Compared with the control (salineinjected) group, the expression of RGMa in the CA3 area was significantly downregulated (P<0.05) from 3 days and still maintained the low expression at 6 weeks in the PTZ group. The expression of FAK (Tyr397) and Ras was upregulated (P<0.05) in the PTZ groups. The Timm score in the CA3 region was significantly higher than that in the control group at different time points and reached a peak at 4 weeks. In the CA3 region, no obvious distinction was observed at the different time points in the control group. To the best of our knowledge, these are the first results to indicate that the RGMaFAKRas pathway may be involved in MFS and the development of temporal lobe epilepsy.
Assuntos
Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Proteínas de Membrana/metabolismo , Fibras Musgosas Hipocampais/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Comportamento Animal , Região CA3 Hipocampal/metabolismo , Região CA3 Hipocampal/patologia , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/fisiopatologia , Proteínas Ligadas por GPI , Imuno-Histoquímica , Masculino , Pentilenotetrazol/efeitos adversos , Ratos , Convulsões/induzido quimicamente , Convulsões/metabolismo , Convulsões/patologia , Convulsões/fisiopatologia , Regulação para CimaRESUMO
OBJECTIVE: To observe the incidence of cerebral apoplexy among the community populations in Changsha, Hunan Province. METHODS: Surveillance of the incidence of cerebral apoplexy and analysis of its subtypes were conducted among 10,000 urban residents in Changsha selected by random cluster sampling from 1986 to 1990. The number of people under surveillance was amplified to 50,000 in 1991 and the studies lasted to December 2000. RESULTS: Among the Chamgsha populations, the annual average incidence of cerebral hemorrhage was 171.7 per 100,000 during the period 1986 - 1990. The annual average incidence of cerebral apoplexy was 238.9/100,000 with an adjusted rate of 200.2/100,000, and the annual average incidence of cerebral hemorrhage, accounting for 53.8% of cerebral apoplexy, was 128.5/100,000 with an adjusted rate of 100.3/100,000). CONCLUSION: The annual average incidence of cerebral hemorrhage in community populations is 128.5 per 100,000 during the period of fifteen years, 1986 - 2000, in Changsha, one of the areas with high incidence of cerebral hemorrhage.
Assuntos
Hemorragia Cerebral/epidemiologia , China/epidemiologia , Feminino , Humanos , Incidência , Imageamento por Ressonância Magnética , Masculino , Fatores de Tempo , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVE: To investigate the influence of reperfusion after ischemia for 90, 120, 180 minutes on the focal ischemia reperfusion animal model. METHODS: The string-fastening method was used to establish focal ischemia-reperfusion models in SD rats and the rats were divided into 4 groups: ischemia-reperfusion for 90, 120 and 180 minute groups and the sham operation group. TTC-dying method was applied to determine the volumes of cerebral infarctions and nerve function grades scoring to estimate the behaviour of the model. RESULTS: TIC-dying method showed that the ischemia area was mainly located in the cortex 2-4 mm behind the optic chiasm. There were no obvious differences among the three groups in the volumes of cerebral infarction, the volumes of cerebral infarctions were larger in the 120 and 180 minute groups than the 90 minute group. The behaviour change of reperfusion after 3 to 6 hours was the most significant in the three groups. CONCLUSION: Cerebral ischemia for 120 minutes is ideal for establishing the animal model.
Assuntos
Isquemia Encefálica , Modelos Animais de Doenças , Traumatismo por Reperfusão , Animais , Comportamento Animal , Feminino , Infarto da Artéria Cerebral Média , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Fatores de TempoRESUMO
Epilepsy is a common and often deleterious neurological condition. Emerging evidence has demonstrated the roles of innate immunity and the associated inflammatory processes in epilepsy. In a previous study, we found that Tolllike receptors (TLRs) are upregulated and promote mossy fiber sprouting (MFS) in an epileptic model. As downstream effectors of TLRs, the activating transcription factor 3 (ATF3) and p53 proteins were shown to be involved in neurite outgrowth. In the present study, we hypothesized that ATF3 and p53 participate in the process of epilepsy and can affect MFS. To investigate this hypothesis, we examined the expression of ATF3 and p53 in hippocampal tissues of rats kindled by pentylenetetrazole (PTZ) using immunofluorescence, immunohistochemistry and western blotting. MFS was evaluated by Timm staining in the hippocampus. Results from these experiments revealed that expression of ATF3 and p53 is significantly higher (p<0.05) in the CA3 area of the hippocampus in the PTZ-treated group compared to the control group. ATF3 expression gradually increased from 3 days to 4 weeks, peaked at 4 weeks and decreased slightly at 6 weeks in the PTZ group, while the expression of p53 was maintained at similar levels at different timepoints following PTZ treatment. No obvious difference in the expression of these proteins was observed between the PTZ and the control group in the dentate gyrus (DG) area (p>0.05). The degree of MFS in the PTZ group peaked at 4 weeks and was maintained at a high level until 6 weeks postPTZ treatment. In conclusion, ATF3 and p53 may be involved in the occurrence of seizure and play critical roles in MFS in the PTZ kindling model.
Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Hipocampo/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Imuno-Histoquímica , Masculino , Pentilenotetrazol/toxicidade , Ratos , Ratos Sprague-Dawley , Convulsões/induzido quimicamente , Convulsões/metabolismo , Convulsões/patologia , Fatores de TempoRESUMO
Mossy fiber sprouting (MFS) is a pathological phenomenon that is commonly observed in temporal lobe epilepsy (TLE). However, the molecular mechanisms underlying MFS remain unclear. It has been demonstrated that the tau protein is important in the progression of MFS by the regulation of microtubule dynamics and axonal transport, with all of these functions of tau modulated by its site-specific phosphorylation. Glycogen synthase kinase-3ß (GSK-3ß) is an active kinase that regulates the phosphorylation of tau protein. Therefore, it was hypothesized that GSK-3ß contributes to MFS by phosphorylating tau protein. The aim of the present study was to determine the expression and activity of GSK-3ß at different regions in the rat hippocampus during the pentylenetetrazole (PTZ)-kindling process in order to demonstrate the possible correlation with MFS, and to investigate the involvement of GSK-3ß in epileptogenesis. Male Sprague-Dawley rats (n=180) were randomly divided into the control and PTZ-treated groups. The chronic epileptic model was established by intraperitoneal injection of PTZ and the hippocampus was observed for the presence of MFS using Timm staining. GSK-3ß mRNA, protein and activity were analyzed in various regions of the hippocampus using in situ hybridization, immunohistochemistry and immunoprecipitation followed by a kinase assay and liquid scintillation counting, respectively. MFS was observed prior to kindling and an increased distribution of Timm granules were observed in the CA3 region of the PTZ-treated rats; however, this was not demonstrated in the supragranular layer of the dentate gyrus. The expression of GSK-3ß mRNA and protein, as well as the GSK-3ß activity, increased significantly from 3 days to 4 weeks in the PTZ group, and this was correlated with the progression of MFS in the CA3 area. In addition, it was demonstrated that MFS did not result from TLE. GSK-3ß may therefore be involved in the progression of MFS and is important in epileptogenesis. An understanding of the molecular mechanisms underlying MFS may lead to the identification of a novel therapeutic target to limit epileptogenesis.