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1.
Proc Natl Acad Sci U S A ; 121(17): e2319607121, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38635635

RESUMO

The development of seizures in epilepsy syndromes associated with malformations of cortical development (MCDs) has traditionally been attributed to intrinsic cortical alterations resulting from abnormal network excitability. However, recent analyses at single-cell resolution of human brain samples from MCD patients have indicated the possible involvement of adaptive immunity in the pathogenesis of these disorders. By exploiting the MethylAzoxyMethanol (MAM)/pilocarpine (MP) rat model of drug-resistant epilepsy associated with MCD, we show here that the occurrence of status epilepticus and subsequent spontaneous recurrent seizures in the malformed, but not in the normal brain, are associated with the outbreak of a destructive autoimmune response with encephalitis-like features, involving components of both cell-mediated and humoral immune responses. The MP brain is characterized by blood-brain barrier dysfunction, marked and persisting CD8+ T cell invasion of the brain parenchyma, meningeal B cell accumulation, and complement-dependent cytotoxicity mediated by antineuronal antibodies. Furthermore, the therapeutic treatment of MP rats with the immunomodulatory drug fingolimod promotes both antiepileptogenic and neuroprotective effects. Collectively, these data show that the MP rat could serve as a translational model of epileptogenic cortical malformations associated with a central nervous system autoimmune response. This work indicates that a preexisting brain maldevelopment predisposes to a secondary autoimmune response, which acts as a precipitating factor for epilepsy and suggests immune intervention as a therapeutic option to be further explored in epileptic syndromes associated with MCDs.


Assuntos
Epilepsia , Acetato de Metilazoximetanol/análogos & derivados , Pilocarpina , Ratos , Humanos , Animais , Autoimunidade , Epilepsia/induzido quimicamente , Epilepsia/patologia , Convulsões/patologia , Encéfalo/patologia , Modelos Animais de Doenças
2.
Clin Sci (Lond) ; 138(9): 555-572, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38602323

RESUMO

Epilepsy, a chronic neurological disorder characterized by recurrent seizures, affects millions of individuals worldwide. Despite extensive research, the underlying mechanisms leading to epileptogenesis, the process by which a normal brain develops epilepsy, remain elusive. We, here, explored the immune system and spleen responses triggered by pilocarpine-induced status epilepticus (SE) focusing on their role in the epileptogenesis that follows SE. Initial examination of spleen histopathology revealed transient disorganization of white pulp, in animals subjected to SE. This disorganization, attributed to immune activation, peaked at 1-day post-SE (1DPSE) but returned to control levels at 3DPSE. Alterations in peripheral blood lymphocyte populations, demonstrated a decrease following SE, accompanied by a reduction in CD3+ T-lymphocytes. Further investigations uncovered an increased abundance of T-lymphocytes in the piriform cortex and choroid plexus at 3DPSE, suggesting a specific mobilization toward the Central Nervous System. Notably, splenectomy mitigated brain reactive astrogliosis, neuroinflammation, and macrophage infiltration post-SE, particularly in the hippocampus and piriform cortex. Additionally, splenectomized animals exhibited reduced lymphatic follicle size in the deep cervical lymph nodes. Most significantly, splenectomy correlated with improved neuronal survival, substantiated by decreased neuronal loss and reduced degenerating neurons in the piriform cortex and hippocampal CA2-3 post-SE. Overall, these findings underscore the pivotal role of the spleen in orchestrating immune responses and neuroinflammation following pilocarpine-induced SE, implicating the peripheral immune system as a potential therapeutic target for mitigating neuronal degeneration in epilepsy.


Assuntos
Doenças Neuroinflamatórias , Pilocarpina , Baço , Estado Epiléptico , Animais , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/patologia , Baço/imunologia , Baço/patologia , Masculino , Doenças Neuroinflamatórias/patologia , Doenças Neuroinflamatórias/induzido quimicamente , Doenças Neuroinflamatórias/imunologia , Esplenectomia , Ratos Sprague-Dawley , Hipocampo/patologia , Modelos Animais de Doenças , Linfócitos T/imunologia , Córtex Piriforme/patologia , Neurônios/patologia
3.
ACS Chem Neurosci ; 15(9): 1937-1947, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38630556

RESUMO

The development of antiepileptic drugs is still a long process. In this study, heparin-modified superparamagnetic iron oxide nanoparticles (UFH-SPIONs) were prepared, and their antiepileptic effect and underlying mechanism were investigated. UFH-SPIONs are stable, homogeneous nanosystems with antioxidant enzyme activity that are able to cross the blood-brain barrier (BBB) and enriched in hippocampal epileptogenic foci. The pretreatment with UFH-SPIONs effectively prolonged the onset of seizures and reduced seizure severity after lithium/pilocarpine (LP)-induced seizures in rats. The pretreatment with UFH-SPIONs significantly decreased the expression of inflammatory factors in hippocampal tissues, including IL-6, IL-1ß, and TNF-α. LP-induced oxidative stress in hippocampal tissues was in turn reduced upon pretreatment with UFH-SPIONs, as evidenced by an increase in the levels of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) and a decrease in the level of lipid peroxidation (MDA). Moreover, the LP-induced upregulation of apoptotic cells was decreased upon pretreatment with UFH-SPIONs. Together, these observations suggest that the pretreatment with UFH-SPIONs ameliorates LP-induced seizures and downregulates the inflammatory response and oxidative stress, which exerts neuronal protection during epilepsy.


Assuntos
Epilepsia do Lobo Temporal , Heparina , Inflamação , Cloreto de Lítio , Nanopartículas Magnéticas de Óxido de Ferro , Estresse Oxidativo , Pilocarpina , Animais , Estresse Oxidativo/efeitos dos fármacos , Ratos , Masculino , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/tratamento farmacológico , Cloreto de Lítio/farmacologia , Heparina/farmacologia , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/induzido quimicamente , Ratos Sprague-Dawley , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Anticonvulsivantes/farmacologia
4.
CNS Neurosci Ther ; 30(3): e14656, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38439573

RESUMO

AIMS: In this study, the anticonvulsant action of closed-loop, low-frequency deep brain stimulation (DBS) was investigated. In addition, the changes in brain rhythms and functional connectivity of the hippocampus and prefrontal cortex were evaluated. METHODS: Epilepsy was induced by pilocarpine in male Wistar rats. After the chronic phase, a tripolar electrode was implanted in the right ventral hippocampus and a monopolar electrode in medial prefrontal cortex (mPFC). Subjects' spontaneous seizure behaviors were observed in continuous video recording, while the local field potentials (LFPs) were recorded simultaneously. In addition, spatial memory was evaluated by the Barnes maze test. RESULTS: Applying hippocampal DBS, immediately after seizure detection in epileptic animals, reduced their seizure severity and duration, and improved their performance in Barnes maze test. DBS reduced the increment in power of delta, theta, and gamma waves in pre-ictal, ictal, and post-ictal periods. Meanwhile, DBS increased the post-ictal-to-pre-ictal ratio of theta band. DBS decreased delta and increased theta coherences, and also increased the post-ictal-to-pre-ictal ratio of coherence. In addition, DBS increased the hippocampal-mPFC coupling in pre-ictal period and decreased the coupling in the ictal and post-ictal periods. CONCLUSION: Applying closed-loop, low-frequency DBS at seizure onset reduced seizure severity and improved memory. In addition, the changes in power, coherence, and coupling of the LFP oscillations in the hippocampus and mPFC demonstrate low-frequency DBS efficacy as an antiepileptic treatment, returning LFPs to a seemingly non-seizure state in subjects that received DBS.


Assuntos
Epilepsia , Pilocarpina , Humanos , Masculino , Ratos , Animais , Pilocarpina/toxicidade , Ratos Wistar , Convulsões/induzido quimicamente , Convulsões/terapia , Anticonvulsivantes , Hipocampo , Aprendizagem em Labirinto
5.
Chem Biol Drug Des ; 103(3): e14481, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38458969

RESUMO

Studies have shown that saikosaponin D (SSD) has favorable neurotherapeutic effects. Therefore, the objective of this study was to explore the efficacy and possible molecular mechanisms of SSD on pilocarpine (PP)-induced astrocyte injury. Primary astrocytes were isolated from juvenile rats and identified using immunofluorescence. The cells were treated with PP and/or SSD for 6 h and 12 h, respectively, followed by measurement of their viability through 3-(4,5-dimethylthiazol)-2,5-diphenyl-tetrazolium bromide (MTT) assay. Next, quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure the expression levels of Glial fibrillary acidic protein (GFAP), C3, S100 calcium binding protein A10 (S100a10), pentraxin 3 (Ptx3), toll-like receptor 4 (TLR4), and RAG in astrocytes after different treatments. Enzyme-linked immunosorbent assay and biochemical tests were utilized to evaluate the level of inflammatory factors [interleukin (IL)-1ß, IL-6, and tumor necrosis factor alpha (TNF-α)] secreted by cells and the content of oxidative stress-related factors (malondialdehyde [MDA] and glutathione [GSH]) or enzyme activity (catalase [CAT] and glutathione peroxidase [GPX]) in cells. The JC-1 mitochondrial membrane potential (MMP) fluorescence probe was used to measure the MMP in astrocytes. Additionally, western blot was applied to test the expression of proteins related to the nod-like receptor protein 3 (NLRP3)/caspase-1 signaling pathway. PP treatment (1 mM) induced cell injury by significantly reducing the viability of astrocytes and expression of cellular markers. SSD treatment (4 µM) had no toxicity to astrocytes. Besides, SSD (4 µM) treatment could significantly up-regulate the cell viability and marker expression of PP-induced astrocytes. Furthermore, SSD could be employed to inhibit inflammation (reduce IL-1ß, IL-6, and TNF-α levels) and oxidative stress (decrease MDA level, elevate GSH level, the activity of CAT and GPX), and ameliorate mitochondrial dysfunction (upregulate JC-1 ratio) in PP-induced astrocytes. Moreover, further mechanism exploration revealed that SSD treatment significantly reduced the activity of the NLRP3/caspase-1 signaling pathway activated by PP induction. SSD increased cell viability, inhibited inflammation and oxidative stress response, and ameliorated mitochondrial dysfunction in PP-induced astrocyte injury model, thus playing a neuroprotective role. The mechanism of SSD may be related to the inhibition of the NLRP3/caspase-1 inflammasome.


Assuntos
Benzimidazóis , Carbocianinas , Doenças Mitocondriais , Proteína 3 que Contém Domínio de Pirina da Família NLR , Ácido Oleanólico/análogos & derivados , Saponinas , Ratos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Astrócitos/metabolismo , Astrócitos/patologia , Pilocarpina/toxicidade , Fator de Necrose Tumoral alfa/genética , Caspases/metabolismo , Interleucina-6 , Transdução de Sinais , Inflamação/metabolismo
6.
Epilepsy Res ; 202: 107355, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38555654

RESUMO

BACKGROUND: The hyperpolarization-activated cyclic nucleotide-gated cation channel (HCN1) is predominantly located in key regions associated with epilepsy, such as the neocortex and hippocampus. Under normal physiological conditions, HCN1 plays a crucial role in the excitatory and inhibitory regulation of neuronal networks. In temporal lobe epilepsy, the expression of HCN1 is decreased in the hippocampi of both animal models and patients. However, whether HCN1 expression changes during epileptogenesis preceding spontaneous seizures remains unclear. OBJECTIVE: The aim of this study was to determine whether the expression of HCN1 is altered during the epileptic prodromal phase, thereby providing evidence for its role in epileptogenesis. METHODS: We utilized a cobalt wire-induced rat epilepsy model to observe changes in HCN1 during epileptogenesis and epilepsy. Additionally, we also compared HCN1 alterations in epileptogenic tissues between cobalt wire- and pilocarpine-induced epilepsy rat models. Long-term video EEG recordings were used to confirm seizures development. Transcriptional changes, translation, and distribution of HCN1 were assessed using high-throughput transcriptome sequencing, total protein extraction, membrane and cytoplasmic protein fractionation, western blotting, immunohistochemistry, and immunofluorescence techniques. RESULTS: In the cobalt wire-induced rat epilepsy model during the epileptogenesis phase, total HCN1 mRNA and protein levels were downregulated. Specifically, the membrane expression of HCN1 was decreased, whereas cytoplasmic HCN1 expression showed no significant change. The distribution of HCN1 in the distal dendrites of neurons decreased. During the epilepsy period, similar HCN1 alterations were observed in the neocortex of rats with cobalt wire-induced epilepsy and hippocampus of rats with lithium pilocarpine-induced epilepsy, including downregulation of mRNA levels, decreased total protein expression, decreased membrane expression, and decreased distal dendrite expression. CONCLUSIONS: Alterations in HCN1 expression and distribution are involved in epileptogenesis beyond their association with seizure occurrence. Similarities in HCN1 alterations observed in epileptogenesis-related tissues from different models suggest a shared pathophysiological pathway in epileptogenesis involving HCN1 dysregulation. Therefore, the upregulation of HCN1 expression in neurons, maintenance of the HCN1 membrane, and distal dendrite distribution in neurons may represent promising disease-modifying strategies in epilepsy.


Assuntos
Modelos Animais de Doenças , Epilepsia , Hipocampo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização , Canais de Potássio , Ratos Sprague-Dawley , Animais , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Masculino , Epilepsia/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/genética , Epilepsia/fisiopatologia , Ratos , Hipocampo/metabolismo , Canais de Potássio/metabolismo , Canais de Potássio/genética , Pilocarpina/toxicidade , Cobalto/farmacologia , Eletroencefalografia , Neurônios/metabolismo , Neocórtex/metabolismo
7.
Sci Rep ; 14(1): 4835, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418461

RESUMO

An increasing number of studies have focused on the role of NEDD4-2 in regulating neuronal excitability and the mechanism of epilepsy. However, the exact mechanism has not yet been elucidated. Here, we explored the roles of NEDD4-2 and the CLC-2 channel in regulating neuronal excitability and mesial temporal lobe epilepsy (MTLE) pathogenesis. First, chronic MTLE models were induced by lithium-pilocarpine in developmental rats. Coimmunoprecipitation analysis revealed that the interaction between CLC-2 and NEDD4-2. Western blot analyses indicated that NEDD4-2 expression was downregulated, while phosphorylated (P-) NEDD4-2 and CLC-2 expression was upregulated in adult MTLE rats. Then, the primary hippocampal neuronal cells were isolated and cultured, and the NEDD4-2 was knocked down by shRNA vector, resulting in decreased protein levels of CLC-2. While CLC-2 absence caused increased NEDD4-2 in cells. Next, in an epileptic cell model induced by a Mg2+-free culture, whole-cell current-clamp recording demonstrated that NEDD4-2 deficiency inhibited the spontaneous action potentials of cells, and CLC-2 absence caused more significant decrease in the spontaneous action potentials of cells. In conclusion, we herein revealed that NEDD4-2 regulates the expression of CLC-2, which is involved in neuronal excitability, and participates in the pathogenesis of MTLE.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Animais , Ratos , Canais de Cloro CLC-2 , Modelos Animais de Doenças , Epilepsia/metabolismo , Epilepsia do Lobo Temporal/metabolismo , Hipocampo/metabolismo , Pilocarpina/efeitos adversos
8.
Epilepsia Open ; 9(2): 665-678, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38321819

RESUMO

OBJECTIVE: The goal of this research was to evaluate the effect of DM type 2 (DM2) on SE severity, neurodegeneration, and brain oxidative stress (OS) secondary to seizures. METHODS: DM2 was induced in postnatal day (P) 3 male rat pups by injecting streptozocin (STZ) 100 mg/kg; control rats were injected with citrate buffer as vehicle. At P90, SE was induced by the lithium-pilocarpine administration and seizure latency, frequency, and severity were evaluated. Neurodegeneration was assessed 24 h after SE by Fluoro-Jade B (F-JB) staining, whereas OS was estimated by measuring lipid peroxidation and reactive oxygen species (ROS). RESULTS: DM2 rats showed an increase in latency to the first generalized seizure and SE onset, had a higher number and a longer duration of seizures, and displayed a larger neurodegeneration in the hippocampus (CA3, CA1, dentate gyrus, and hilus), the piriform cortex, the dorsomedial nucleus of the thalamus and the cortical amygdala. Our results also show that only SE, neither DM2 nor the combination of DM2 with SE, caused the increase in ROS and brain lipid peroxidation. SIGNIFICANCE: DM2 causes higher seizure severity and neurodegeneration but did not exacerbate SE-induced OS under these conditions. PLAIN LANGUAGE SUMMARY: Our research performed in animal models suggests that type 2 diabetes mellitus (DM2) may be a risk factor for causing higher seizure severity and seizure-induced neuron cell death. However, even when long-term seizures promote an imbalance between brain pro-oxidants and antioxidants, DM2 does not exacerbate that disproportion.


Assuntos
Diabetes Mellitus Tipo 2 , Estado Epiléptico , Ratos , Animais , Masculino , Diabetes Mellitus Tipo 2/complicações , Espécies Reativas de Oxigênio/efeitos adversos , Pilocarpina/efeitos adversos , Convulsões , Estado Epiléptico/induzido quimicamente , Estresse Oxidativo
9.
Sci Rep ; 14(1): 5063, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424459

RESUMO

The ketogenic diet (KD) has been shown to be effective in refractory epilepsy after long-term administration. However, its interference with short-term brain metabolism and its involvement in the early process leading to epilepsy remain poorly understood. This study aimed to assess the effect of a short-term ketogenic diet on cerebral glucose metabolic changes, before and after status epilepticus (SE) in rats, by using [18F]-FDG PET. Thirty-nine rats were subjected to a one-week KD (KD-rats, n = 24) or to a standard diet (SD-rats, n = 15) before the induction of a status epilepticus (SE) by lithium-pilocarpine administrations. Brain [18F]-FDG PET scans were performed before and 4 h after this induction. Morphological MRIs were acquired and used to spatially normalize the PET images which were then analyzed voxel-wisely using a statistical parametric-based method. Twenty-six rats were analyzed (KD-rats, n = 15; SD-rats, n = 11). The 7 days of the KD were associated with significant increases in the plasma ß-hydroxybutyrate level, but with an unchanged glycemia. The PET images, recorded after the KD and before SE induction, showed an increased metabolism within sites involved in the appetitive behaviors: hypothalamic areas and periaqueductal gray, whereas no area of decreased metabolism was observed. At the 4th hour following the SE induction, large metabolism increases were observed in the KD- and SD-rats in areas known to be involved in the epileptogenesis process late-i.e., the hippocampus, parahippocampic, thalamic and hypothalamic areas, the periaqueductal gray, and the limbic structures (and in the motor cortex for the KD-rats only). However, no statistically significant difference was observed when comparing SD and KD groups at the 4th hour following the SE induction. A one-week ketogenic diet does not prevent the status epilepticus (SE) and associated metabolic brain abnormalities in the lithium-pilocarpine rat model. Further explorations are needed to determine whether a significant prevention could be achieved by more prolonged ketogenic diets and by testing this diet in less severe experimental models, and moreover, to analyze the diet effects on the later and chronic stages leading to epileptogenesis.


Assuntos
Dieta Cetogênica , Estado Epiléptico , Ratos , Animais , Pilocarpina/farmacologia , Lítio/farmacologia , Ratos Wistar , Fluordesoxiglucose F18/farmacologia , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Hipocampo , Modelos Animais de Doenças
10.
Eur J Med Res ; 29(1): 121, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355613

RESUMO

INTRODUCTION: Epilepsy is a common neurological disorder that presents with challenging mechanisms and treatment strategies. This study investigated the neuroprotective effects of quinpirole on lithium chloride pilocarpine-induced epileptic rats and explored its potential mechanisms. METHODS: Lithium chloride pilocarpine was used to induce an epileptic model in rats, and the effects of quinpirole on seizure symptoms and cognitive function were evaluated. The Racine scoring method, electroencephalography, and Morris water maze test were used to assess seizure severity and learning and memory functions in rats in the epileptic group. Additionally, immunohistochemistry and Western blot techniques were used to analyze the protein expression levels and morphological changes in glutamate receptor 2 (GluR2; GRIA2), BAX, and BCL2 in the hippocampi of rats in the epileptic group. RESULTS: First, it was confirmed that the symptoms in rats in the epileptic group were consistent with features of epilepsy. Furthermore, these rats demonstrated decreased learning and memory function in the Morris water maze test. Additionally, gene and protein levels of GluR2 in the hippocampi of rats in the epileptic group were significantly reduced. Quinpirole treatment significantly delayed seizure onset and decreased the mortality rate after the induction of a seizure. Furthermore, electroencephalography showed a significant decrease in the frequency of the spike waves. In the Morris water maze test, rats from the quinpirole treatment group demonstrated a shorter latency period to reach the platform and an increased number of crossings through the target quadrant. Network pharmacology analysis revealed a close association between quinpirole and GluR2 as well as its involvement in the cAMP signaling pathway, cocaine addiction, and dopaminergic synapses. Furthermore, immunohistochemistry and Western blot analysis showed that quinpirole treatment resulted in a denser arrangement and a more regular morphology of the granule cells in the hippocampi of rats in the epileptic group. Additionally, quinpirole treatment decreased the protein expression of BAX and increased the protein expression of BCL2. CONCLUSION: The current study demonstrated that quinpirole exerted neuroprotective effects in the epileptic rat model induced by lithium chloride pilocarpine. Additionally, it was found that the treatment not only alleviated the rats' seizure symptoms, but also improved their learning and memory abilities. This improvement was linked to the modulation of protein expression levels of GLUR2, BAX, and BCL2. These findings provided clues that would be important for further investigation of the therapeutic potential of quinpirole and its underlying mechanisms for epilepsy treatment.


Assuntos
Epilepsia , Fármacos Neuroprotetores , Ratos , Animais , Pilocarpina/toxicidade , Pilocarpina/uso terapêutico , Cloreto de Lítio/uso terapêutico , Fármacos Neuroprotetores/efeitos adversos , Quimpirol/efeitos adversos , Proteína X Associada a bcl-2/uso terapêutico , Epilepsia/induzido quimicamente , Epilepsia/tratamento farmacológico , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Modelos Animais de Doenças
11.
Int J Mol Sci ; 25(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38338969

RESUMO

In humans and animal models, temporal lobe epilepsy (TLE) is associated with reorganization of hippocampal neuronal networks, gliosis, neuroinflammation, and loss of integrity of the blood-brain barrier (BBB). More than 30% of epilepsies remain intractable, and characterization of the molecular mechanisms involved in BBB dysfunction is essential to the identification of new therapeutic strategies. In this work, we induced status epilepticus in rats through injection of the proconvulsant drug pilocarpine, which leads to TLE. Using RT-qPCR, double immunohistochemistry, and confocal imaging, we studied the regulation of reactive glia and vascular markers at different time points of epileptogenesis (latent phase-3, 7, and 14 days; chronic phase-1 and 3 months). In the hippocampus, increased expression of mRNA encoding the glial proteins GFAP and Iba1 confirmed neuroinflammatory status. We report for the first time the concomitant induction of the specific proteins CD31, PDGFRß, and ColIV-which peak at the same time points as inflammation-in the endothelial cells, pericytes, and basement membrane of the BBB. The altered expression of these proteins occurs early in TLE, during the latent phase, suggesting that they could be associated with the early rupture and pathogenicity of the BBB that will contribute to the chronic phase of epilepsy.


Assuntos
Barreira Hematoencefálica , Epilepsia do Lobo Temporal , Epilepsia , Receptor beta de Fator de Crescimento Derivado de Plaquetas , Estado Epiléptico , Animais , Humanos , Ratos , Barreira Hematoencefálica/metabolismo , Colágeno/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Epilepsia/metabolismo , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Hipocampo/metabolismo , Neuroglia/metabolismo , Pericitos/metabolismo , Pilocarpina/efeitos adversos , Ratos Sprague-Dawley , Estado Epiléptico/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Receptores do Fator de Crescimento Derivado de Plaquetas/genética , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo
12.
Eur J Pharmacol ; 966: 176375, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38307381

RESUMO

The role of the Wnt/ß-catenin signaling pathway in epilepsy and the effects of its modulators as efficacious treatment options, though postulated, has not been sufficiently investigated. We evaluated the involvement of ß-catenin and GSK-3ß, the significant proteins in this pathway, in the lithium chloride-pilocarpine-induced status epilepticus model in rodents to study acute phase of temporal lobe epilepsy (TLE). The modulators studied were 6-BIO, a GSK-3ß inhibitor and Sulindac, a Dvl protein inhibitor. The disease group exhibited increased seizure score and seizure frequency, and the assessment of neurobehavioral parameters indicated notable alterations. Furthermore, histopathological examination of hippocampal brain tissues revealed significant neurodegeneration. Immunohistochemical study of hippocampus revealed neurogenesis in 6-BIO and sulindac groups. The gene and protein expression by RT-qPCR and western blotting studies indicated Wnt/ß-catenin pathway downregulation and increased apoptosis in the acute phase of TLE. 6-BIO was very efficient in upregulating the Wnt pathway, decreasing neuronal damage, increasing neurogenesis in hippocampus and decreasing seizure score and frequency in comparison to sulindac. This suggests that both GSK-3ß and ß-catenin are potential and novel drug targets for acute phase of TLE, and treatment options targeting these proteins could be beneficial in successfully managing acute epilepsy. Further evaluation of 6-BIO to explore its therapeutic potential in other models of epilepsy should be conducted.


Assuntos
Epilepsia do Lobo Temporal , Estado Epiléptico , Ratos , Animais , Pilocarpina , Via de Sinalização Wnt/fisiologia , Lítio/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , beta Catenina/metabolismo , Sulindaco/efeitos adversos , Sulindaco/metabolismo , Hipocampo/metabolismo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/metabolismo , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/metabolismo , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/tratamento farmacológico
13.
Arch Dis Child ; 109(4): 304-307, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38253430

RESUMO

OBJECTIVE: To verify the rate and predictors of 'quantity not sufficient' (QNS) among Brazilian infants younger than 3 months with positive newborn screening (NBS) for cystic fibrosis (CF). DESIGN: Prospective, population-based study. SETTING: Public Statewide Newborn Screening Programme where the incidence rate of CF is ≈1:11 000. PATIENTS: Subjects with positive two-tiered immunoreactive trypsinogen. INTERVENTIONS: Sweat induction and collection were performed in the same facility; one sweat sample was obtained per individual. MAIN OUTCOME MEASURES: The QNS rate and its predictors; analysis corresponded to the day of sweat collection. RESULTS: Among the 975 participants, QNS rates for 10 and 15 µL were 3.6% (95% CI 2.5% to 4.9%) and 8.3% (95% CI 6.6% to 10.2%). Infants weighing >3056 and >3845 g and with gestational age higher than 37 weeks had a greater likelihood (5.5 and 6.7, and 2.7 and 5.8 times more, respectively) of avoiding QNS than their peers. CONCLUSION: QNS rates fulfilled the requirements, but predictors differed from those recommended by the Cystic Fibrosis Foundations guidelines.


Assuntos
Fibrose Cística , Pilocarpina , Recém-Nascido , Lactente , Humanos , Fibrose Cística/diagnóstico , Fibrose Cística/epidemiologia , Iontoforese , Suor/química , Estudos Prospectivos , Triagem Neonatal , Tripsinogênio , Regulador de Condutância Transmembrana em Fibrose Cística , Cloretos/análise
14.
Clin Ther ; 46(2): 104-113, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38216351

RESUMO

PURPOSE: This study was undertaken to evaluate the safety and efficacy of CSF-1 (0.4% pilocarpine hydrochloride ophthalmic solution) for use in individuals with presbyopia. METHODS: Two Phase 3 multicenter, randomized, double-masked, vehicle-controlled, parallel-group clinical trials were conducted in 35 private ophthalmology clinics in the United States from October 2020 to February 2022. Key inclusion criteria were the following: (1) age 45-64 years, (2) distance-corrected near visual acuity (DCNVA) at 40 cm ≥0.40 and ≤0.90 logarithm of the minimum angle of resolution (logMAR, approximately 20/50-20/160 Snellen) in at least 1 eye, (3) manifest refraction (MR) between -4.50 and +2.00 diopter (D) sphere in each eye with ≤2.00D difference between eyes, (4) <2.00D of cylinder MR in each eye, (5) ≤0.04 logMAR (20/20-2 or better) corrected distance visual acuity (CDVA) at 4 m in each eye. Key exclusion criteria were the following: (1) >0.14 logMAR (7 letters) improvement in post-vehicle treatment in monocular DCNVA in either eye at visit 1, (2) introcular pressure (IOP) <9 or >22 mm Hg, (3) average dark-adapted pupillometry <3.5 mm in either eye, (4) prior refractive surgery or intraocular lens (IOL) implantation. Participants applied CSF-1 or vehicle twice per day for 2 weeks. Efficacy and safety assessments were performed at several times on days 1, 8, and 15. Response was defined as ≥3-line gain in DCNVA without loss of ≥1-line in CDVA in the study eye under mesopic room lighting conditions. The primary efficacy endpoint was measured 1 hour post-dose 1 on day 8. Key secondary endpoints were 2 hours post-dose 1, and 1 and 2 hours post-dose 2, also on day 8. Safety endpoints were ocular and non-ocular treatment-related adverse events (TRAE), conjunctival redness, drop comfort, slit-lamp biomicroscopy, intraocular pressure, indirect fundoscopy, and CDVA at 4 m. FINDINGS: Six hundred thirteen participants were randomized to CSF-1 (n = 309) or vehicle (n = 304). Participants were predominantly White (80.8%) and female (62.0%), with mean age (standard deviation) of 54.7 (4.8). CSF-1 met the primary and key secondary endpoints. At the primary endpoint, 40.1% of the CSF-1 group achieved response versus 19.1% of the vehicle group (P < 0.0001). The percentage of responders was significantly greater in CSF-1 compared with vehicle at all tested times. Changes from baseline in all safety endpoints were comparable between groups. Most adverse events (AEs) were mild and transient. Neither serious nor severe AEs were reported with CSF-1. IMPLICATIONS: CSF-1, a low-dose pilocarpine ophthalmic solution, demonstrated superiority to vehicle in improving near vision in individuals with presbyopia without compromising distance vision. CSF-1 demonstrated a favorable safety profile. CLINICALTRIALS: gov identifier: NCT04599933 (NEAR-1), NCT04599972 (NEAR-2).


Assuntos
Lentes Intraoculares , Presbiopia , Feminino , Humanos , Pessoa de Meia-Idade , Implante de Lente Intraocular/efeitos adversos , Implante de Lente Intraocular/métodos , Fator Estimulador de Colônias de Macrófagos , Soluções Oftálmicas/efeitos adversos , Pilocarpina/efeitos adversos , Presbiopia/tratamento farmacológico , Presbiopia/complicações
15.
Neurobiol Dis ; 192: 106424, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290566

RESUMO

BACKGROUND: Managing refractory epilepsy presents a significant a substantial clinical challenge. Deep brain stimulation (DBS) has emerged as a promising avenue for addressing refractory epilepsy. However, the optimal stimulation targets and effective parameters of DBS to reduce seizures remian unidentified. OBJECTIVES: This study endeavors to scrutinize the therapeutic potential of DBS within the zona incerta (ZI) across diverse seizure models and elucidate the associated underlying mechanisms. METHODS: We evaluated the therapeutic potential of DBS with different frequencies in the ZI on kainic acid (KA)-induced TLE model or M1-cortical seizures model, pilocarpine-induced M1-cortical seizure models, and KA-induced epilepsy model. Further, employing calcium fiber photometry combined with cell-specific ablation, we sought to clarified the causal role of ZI GABAergic neurons in mediating the therapeutic effects of DBS. RESULTS: Our findings reveal that DBS in the ZI alleviated the severity of seizure activities in the KA-induced TLE model. Meanwhile, DBS attenuated seizure activities in KA- or pilocarpine-induced M1-cortical seizure model. In addition, DBS exerts a mitigating influence on KA induced epilepsy model. DBS in the ZI showed anti-seizure effects at low frequency spectrum, with 5 Hz exhibiting optimal efficacy. The low-frequency DBS significantly increased the calcium activities of ZI GABAergic neurons. Furthermore, selective ablation of ZI GABAergic neurons with taCasp3 blocked the anti-seizure effect of low-frequency DBS, indicating the anti-seizure effect of DBS is mediated by the activation of ZI GABAergic neurons. CONCLUSION: Our results demonstrate that low-frequency DBS in the ZI attenuates seizure via driving GABAergic neuronal activity. This suggests that the ZI represents a potential DBS target for treating both hippocampal and cortical seizure through the activation of GABAergic neurons, thereby holding therapeutic significance for seizure treatment.


Assuntos
Estimulação Encefálica Profunda , Epilepsia Resistente a Medicamentos , Epilepsia , Zona Incerta , Humanos , Pilocarpina/toxicidade , Cálcio , Estimulação Encefálica Profunda/métodos , Neurônios GABAérgicos , Epilepsia/terapia , Ácido Caínico/toxicidade , Convulsões/terapia
16.
JCI Insight ; 9(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38193536

RESUMO

Prolonged seizures can disrupt stem cell behavior in the adult hippocampus, an important brain structure for spatial memory. Here, using a mouse model of pilocarpine-induced status epilepticus (SE), we characterized spatiotemporal expression of Lin28a mRNA and proteins after SE. Unlike Lin28a transcripts, induction of LIN28A protein after SE was detected mainly in the subgranular zone, where immunoreactivity was found in progenitors, neuroblasts, and immature and mature granule neurons. To investigate roles of LIN28A in epilepsy, we generated Nestin-Cre:Lin28aloxP/loxP (conditional KO [cKO]) and Nestin-Cre:Lin28a+/+ (WT) mice to block LIN28A upregulation in all neuronal lineages after acute seizure. Adult-generated neuron- and hippocampus-associated cognitive impairments were absent in epileptic LIN28A-cKO mice, as evaluated by pattern separation and contextual fear conditioning tests, respectively, while sham-manipulated WT and cKO animals showed comparable memory function. Moreover, numbers of hilar PROX1-expressing ectopic granule cells (EGCs), together with PROX1+/NEUN+ mature EGCs, were significantly reduced in epileptic cKO mice. Transcriptomics analysis and IHC validation at 3 days after pilocarpine administration provided potential LIN28A downstream targets such as serotonin receptor 4. Collectively, our findings indicate that LIN28A is a potentially novel target for regulation of newborn neuron-associated memory dysfunction in epilepsy by modulating seizure-induced aberrant neurogenesis.


Assuntos
Epilepsia , Estado Epiléptico , Animais , Nestina/genética , Pilocarpina/toxicidade , Convulsões/induzido quimicamente , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/genética , Hipocampo , Neurogênese
17.
Neurochem Int ; 174: 105677, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38290616

RESUMO

It is widely acknowledged that epilepsy is a neurological disorder characterized by recurrent and atypical neuronal discharges, resulting in transient dysfunction within the brain. The protective role of hydrogen sulfide (H2S) in epilepsy has been elucidated by recent studies, but the underlying mechanisms remain poorly understood. To investigate this, the concentration of H2S was measured by spectrophotometry and a fluorescent probe in LiCl/Pilocarpine (LiCl/Pilo)-induced seizures in rats. The localization of proteins was examined using immunofluorescence. Electroencephalogram and behavioral tests were employed to evaluate the occurrence of seizures. Neuropathological changes in the hippocampus were examined by hematoxylin-eosin staining, Nissl staining, and transmission electron microscopy. Through proteomics and bioinformatics analysis, we identified the differential proteins in the hippocampus of rats following H2S intervention. Protein changes were detected through western blotting. The results showed that H2S treatment significantly alleviated seizures and minimized post-seizures neurological damage in rats. Proteomics analysis revealed adenylate cyclase 3 (AC3) as a protein potentially targeted by H2S. Moreover, the AC3 activator forskolin reversed the downregulation effect of H2S on the AC3/cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA)/transient receptor potential vanilloid 2 (TRPV2) signaling pathway. In conclusion, H2S targets and downregulates the expression of AC3, thereby modulating the AC3/cAMP/PKA signaling pathway to regulate the expression of TRPV2 in LiCl/Pilo-induced seizures, ultimately leading to seizure inhibition and neuroprotection.


Assuntos
Adenilil Ciclases , Epilepsia , Pilocarpina , Ratos , Animais , Pilocarpina/toxicidade , Neuroproteção , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Convulsões/induzido quimicamente , Convulsões/prevenção & controle , Convulsões/metabolismo , AMP Cíclico/metabolismo , Epilepsia/induzido quimicamente
18.
Epilepsy Res ; 200: 107296, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219422

RESUMO

Mutations within the Kv7.2 and Kv7.3 genes are well described causes for genetic childhood epilepsies. Knowledge on these channels in acquired focal epilepsy, especially in mesial temporal lobe epilepsy (mTLE), however, is scarce. Here, we used the rat pilocarpine model of drug-resistant mTLE to elucidate both expression and function by quantitative polymerase-chain reaction, immunohistochemistry, and electrophysiology, respectively. We found transcriptional downregulation of Kv7.2 and Kv7.3 as well as reduced Kv7.2 expression in epileptic CA1. Consequences were altered synaptic transmission, hyperexcitability which consisted of epileptiform afterpotentials, and increased susceptibility to acute GABAergic disinhibition. Importantly, blocking Kv7 channels with XE991 increased hyperexcitability in control tissue, but not in chronically epileptic tissue suggesting that the Kv7 deficit had precluded XE991 effects in this tissue. Conversely, XE991 resulted in comparable reduction of the paired-pulse ratio in both experimental groups implying preserved presynaptic Kv7.2 function of Schaffer collateral terminals. Consistent with Kv7.2/7.3 downregulation, the Kv7.3 channel opener ß-hydroxybutyrate failed to mitigate hyperexcitability. Our findings demonstrate that compromised Kv7 function is not only relevant in genetic epilepsy, but also in acquired focal epilepsy. Moreover, they help explain reduced anti-seizure efficacy of Kv7 channel openers in drug-resistant epilepsy.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Humanos , Ratos , Animais , Criança , Pilocarpina/toxicidade , Epilepsia do Lobo Temporal/induzido quimicamente , Regulação para Baixo , Potenciais da Membrana
19.
BMC Complement Med Ther ; 24(1): 49, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254071

RESUMO

BACKGROUND: The continuous evolution of drug-resistant influenza viruses highlights the necessity for repurposing naturally-derived and safe phytochemicals with anti-influenza activity as novel broad-spectrum anti-influenza medications. METHODS: In this study, nitrogenous alkaloids were tested for their viral inhibitory activity against influenza A/H1N1 and A/H5N1 viruses. The cytotoxicity of tested alkaloids on MDCK showed a high safety range (CC50 > 200 µg/ml), permitting the screening for their anti-influenza potential. RESULTS: Herein, atropine sulphate, pilocarpine hydrochloride and colchicine displayed anti-H5N1 activities with IC50 values of 2.300, 0.210 and 0.111 µg/ml, respectively. Validation of the IC50 values was further depicted by testing the three highly effective alkaloids, based on their potent IC50 values against seasonal influenza A/H1N1 virus, showing comparable IC50 values of 0.204, 0.637 and 0.326 µg/ml, respectively. Further investigation suggests that colchicine could suppress viral infection by primarily interfering with IAV replication and inhibiting viral adsorption, while atropine sulphate and pilocarpine hydrochloride could directly affect the virus in a cell-free virucidal effect. Interestingly, the in silico molecular docking studies suggest the abilities of atropine, pilocarpine, and colchicine to bind correctly inside the active sites of the neuraminidases of both influenza A/H1N1 and A/H5N1 viruses. The three alkaloids exhibited good binding energies as well as excellent binding modes that were similar to the co-crystallized ligands. On the other hand, consistent with in vitro results, only colchicine could bind correctly against the M2-proton channel of influenza A viruses (IAVs). This might explicate the in vitro antiviral activity of colchicine at the replication stage of the virus replication cycle. CONCLUSION: This study highlighted the anti-influenza efficacy of biologically active alkaloids including colchicine. Therefore, these alkaloids should be further characterized in vivo (preclinical and clinical studies) to be developed as anti-IAV agents.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Vírus da Influenza A , Influenza Humana , Humanos , Colchicina/farmacologia , Pilocarpina , Influenza Humana/tratamento farmacológico , Simulação de Acoplamento Molecular , Estações do Ano , Compostos Fitoquímicos/farmacologia , Atropina , Antivirais/farmacologia
20.
Behav Brain Res ; 462: 114833, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38220059

RESUMO

Depression and anxiety are associated with dysfunction of the mesolimbic dopamine system. The rostromedial tegmental nucleus (RMTg) is predominantly composed of GABAergic neurons that exhibit dense projections and strongly inhibit mesolimbic dopaminergic neurons, proposed as a major "brake" for the system. Consequently, the RMTg may be a crucial brain region for regulating these emotions. The central cholinergic system, particularly the muscarinic receptors, plays an important regulatory role in depression and anxiety. M3 muscarinic receptors are distributed on GABAergic neurons in the RMTg, but their involvement in the regulation of depression and anxiety remains uncertain. This study aimed to examine the effects of RMTg M3 muscarinic receptors on regulating depression- and anxiety-like behaviors in adult male Wistar rats, as assessed through the forced swim, tail suspension, and elevated plus maze tests. The results showed that intra-RMTg injections of the M1/M3 muscarinic receptors agonist, pilocarpine (3, 10, and 30 µg/side), or the M3 muscarinic receptors antagonist, 4-DAMP (0.5, 1, and 2 µg/side), did not alter the immobility time in the forced swim and tail suspension tests. Additionally, pilocarpine (30 µg/side) decreased time spent in open arms and increased time in closed arms in the elevated plus maze; while 4-DAMP (1 and 2 µg/side) played the opposite role by increasing time spent in open arms and decreasing time in closed arms. These findings suggest that RMTg M3 muscarinic receptors have differential effects on regulating depression- and anxiety-like behaviors. Enhancing or inhibiting these receptors can produce anxiogenic or anxiolytic effects, but have no impact on depression-like behavior. Therefore, RMTg M3 muscarinic receptors are involved in regulating anxiety and may be a potential therapeutic target for anxiolytic drugs.


Assuntos
Pilocarpina , Piperidinas , Área Tegmentar Ventral , Ratos , Animais , Masculino , Pilocarpina/farmacologia , Depressão/tratamento farmacológico , Ratos Wistar , Receptores Muscarínicos , Ansiedade/tratamento farmacológico
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