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1.
Neurochem Int ; 175: 105705, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38412923

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease that seriously threatens the quality of life of the elderly. Its pathogenesis has not yet been fully elucidated. Ferroptosis, a cell death caused by excessive accumulation of iron-dependent lipid peroxides, has been implicated in the pathogenesis of AD. Uncontrolled lipid peroxidation is the core process of ferroptosis, and inhibiting lipid peroxidation of ferroptosis may be an important therapeutic target for AD. Based on previous studies, we mixed standards of icariin, astragaloside IV, and puerarin, named the standard mixture YHG, and investigated the effect of YHG on ferroptosis -lipid peroxidation in APP/PS1 mice. DFX, a ferroptosis inhibitor, was used as a control drug. In this study, APP/PS1 mice were used as an AD animal model, and behavioral experiments, iron level detection, Transmission electron microscopy (TEM) observation, lipid peroxidation level detection, antioxidant capacity detection, immunofluorescence, Western blot and real-time qPCR were performed. It was found that YHG could reduce body weight, significantly improve abnormal behaviors and the ultrastructure of hippocampal neurons in APP/PS1 mice. The results of biochemical tests showed that YHG reduced the contents of iron, malondialdehyde (MDA) and lipid peroxide (LPO) in brain tissue and serum, and increased the levels of superoxide dismutase (SOD) and reduced glutathione (GSH). Immunofluorescence, WesternBlot and real-time qPCR results showed that YHG could promote the expression of solute carrier family 7 member 11 (SLC7A11), solute carrier family 3 member 2 (SLC3A2) and glutathione peroxidase 4(GPX4). Inhibited the expression of long-chain acyllipid coenzyme a synthetase 4(ACSL4) and lysophosphatidyltransferase 3 (LPCAT3). This study suggests that the mechanism by which YHG improves cognitive dysfunction in APP/PS1 mice may be related to the inhibition of ferroptosis-lipid peroxidation.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Ferroptose , Flavonoides , Isoflavonas , Doenças Neurodegenerativas , Saponinas , Triterpenos , Humanos , Idoso , Animais , Camundongos , Peroxidação de Lipídeos , Qualidade de Vida , Peróxidos Lipídicos , Doença de Alzheimer/tratamento farmacológico , Ferro , 1-Acilglicerofosfocolina O-Aciltransferase
2.
Eur J Med Res ; 29(1): 126, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365822

RESUMO

OBJECTIVE: To investigate the value of dual-energy dual-source computed tomography (DSCT) in evaluating pulmonary perfusion changes before and after radiotherapy for esophageal cancer, and its clinical use in the early diagnosis of acute radiation pneumonia (ARP). METHODS: We selected 45 patients with pathologically confirmed esophageal cancer who received radiotherapy (total irradiation dose of 60 Gy). Dual-energy DSCT scans were performed before and after radiotherapy and the normalized iodine concentrations (NIC) in the lung fields of the areas irradiated with doses of > 20 Gy, 10-20 Gy, 5-10 Gy, and < 5 Gy were measured. We also checked for the occurrence of ARP in the patients, and the differences in NIC values and NIC reduction rates before and after radiotherapy were calculated and statistically analyzed. RESULTS: A total of 16 of the 45 patients developed ARP. The NIC values in the lung fields of all patients decreased at different degrees after radiotherapy, and the NIC values in the area where ARP developed, decreased significantly. The rate of NIC reduction and incidence rate of ARP increased gradually with the increasing irradiation dose, and the inter-group difference in NIC reduction rate was statistically significant (P < 0.05). Based on the receiver operating characteristic (ROC) curve analysis, the areas under the curves of NIC reduction rate versus ARP occurrence in the V5-10 Gy, V10-20 Gy, and V> 20 Gy groups were 0.780, 0.808, and 0.772, respectively. Sensitivity of diagnosis was 81.3%, 75.0%, and 68.8% and the specificity was 65.5%, 82.8%, and 79.3%, when taking 12.50%, 16.50%, and 26.0% as the diagnostic thresholds, respectively. The difference in NIC values in the lung fields of V<5 Gy before and after radiotherapy was not statistically significant (P > 0.05). CONCLUSION: The dual-energy DSCT could effectively evaluate pulmonary perfusion changes after radiotherapy for esophageal cancer, and the NIC reduction rate was useful as a reference index to predict ARP and provide further reference for decisions in clinical practice.


Assuntos
Lesão Pulmonar Aguda , Neoplasias Esofágicas , Iodo , Pneumonite por Radiação , Humanos , Pneumonite por Radiação/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Pulmão , Curva ROC , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/radioterapia
3.
Phytochemistry ; 214: 113823, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37579813

RESUMO

Six undescribed clerodane diterpenoids along with five known ones were isolated from the aerial parts of Salvia deserta, a traditional Uygur medicine. Their chemical structures including absolute configurations were elucidated by extensive spectroscopic analysis (including 1D and 2D NMR, HRESIMS, and IR), combined with calculated ECD method and single-crystal X-ray diffraction analysis. All the compounds possessed a terminal α,ß-unsaturated-γ-lactone moiety, and were assayed for their immunosuppressive activity via inhibiting the secretion of cytokines TNF-α and IL-6 in macrophages RAW264.7. Among them, (5R,8R,9S,10R)-18-nor-cleroda-2,13-dien-16,15-olide-4-one obviously suppressed the secretion of TNF-α and IL-6 with IC50 values of 8.55 and 13.65 µM, respectively.


Assuntos
Diterpenos Clerodânicos , Diterpenos , Salvia , Diterpenos Clerodânicos/farmacologia , Diterpenos Clerodânicos/química , Salvia/química , Interleucina-6 , Fator de Necrose Tumoral alfa , Componentes Aéreos da Planta/química , Estrutura Molecular , Diterpenos/química
4.
Phytochemistry ; 210: 113642, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36933879

RESUMO

Detailed phytochemical investigation on the traditional Chinese medicine Swertia pseudochinensis Hara led to the isolation of ten undescribed secoiridoids and fifteen known analogs. Their structures were elucidated by extensive spectroscopic analysis (including 1D and 2D NMR, and HRESIMS). Selected isolates were assayed for their anti-inflammatory and antibacterial activities, and moderate anti-inflammatory activity via inhibiting the secretion of cytokines IL-6 and TNF-α in macrophages RAW264.7 induced by LPS were observed. Antibacterial activity against Staphylococcus aureus was not found at 100 µM.


Assuntos
Medicamentos de Ervas Chinesas , Swertia , Medicina Tradicional Chinesa , Swertia/química , Iridoides/química , Medicamentos de Ervas Chinesas/farmacologia , Anti-Inflamatórios/farmacologia , Estrutura Molecular
5.
Zhongguo Zhong Yao Za Zhi ; 46(23): 6224-6230, 2021 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-34951249

RESUMO

Alzheimer's disease(AD) patients in China have been surging, and the resultant medical burden and care demand have a huge impact on the development of individuals, families, and the society. The active component compound of Epimedii Folium, Astragali Radix, and Puerariae Lobatae Radix(YHG) can regulate the expression of iron metabolism-related proteins to inhibit brain iron overload and relieve hypofunction of central nervous system in AD patients. Hepcidin is an important target regulating iron metabolism. This study investigated the effect of YHG on the expression of a disintegrin and metalloprotease-17(ADAM17), a key enzyme in the hydrolysis of ß amyloid precursor protein(APP) in HT22 cells, by mediating hepcidin. To be specific, HT22 cells were cultured in vitro, followed by liposome-mediated siRNA transfection to silence the expression of hepcidin. Real-time PCR and Western blot were performed to examine the silencing result and the effect of YHG on hepcidin in AD cell model. HT22 cells were randomized into 7 groups: control group, Aß25-35 induction(Aß) group, hepcidin-siRNA(siRNA) group, Aß25-35 + hepcidin-siRNA(Aß + siRNA) group, Aß25-35+YHG(Aß+YHG) group, hepcidin-siRNA+YHG(siRNA+YHG) group, Aß25-35+hepcidin-siRNA+YHG(Aß+siRNA+YHG) group. The expression of ADAM17 mRNA in cells was detected by real-time PCR, and the expression of ADAM17 protein by immunofluorescence and Western blot. Immunofluorescence showed that the ADAM17 protein expression was lower in the Aß group, siRNA group, and Aß+siRNA group than in the control group(P<0.05) and the expression was lower in the Aß+siRNA group(P<0.05) and higher in the Aß+YHG group(P<0.05) than in the Aß group. Moreover, the ADAM17 protein expression was lower in the Aß+siRNA group(P<0.05) and higher in the siRNA+YHG group(P< 0.05) than in the siRNA group. The expression was higher in the Aß+siRNA+YHG group than in the Aß+siRNA group(P<0.05). The results of Western blot and real-time PCR were consistent with those of immunofluorescence. The experiment showed that YHG induced hepcidin to up-regulate the expression of ADAM17 in AD cell model and promote the activation of non-starch metabolic pathways, which might be the internal mechanism of YHG in preventing and treating AD.


Assuntos
Doença de Alzheimer , Medicamentos de Ervas Chinesas , Pueraria , Proteína ADAM17 , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides , Medicamentos de Ervas Chinesas/farmacologia , Hepcidinas/genética , Humanos
6.
Neuropsychiatr Dis Treat ; 17: 649-657, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33658786

RESUMO

BACKGROUND: This study aimed to examine the differences in anxiety and depression between infertile Chinese couples in diverse stages of in vitro fertilization-embryo transfer (IVF-ET) and their relationship with the IVF-ET outcomes. METHODS: From February 2016 to December 2018, a total of 247 couples that were undergoing IVF-ET were randomly selected for this study. On the day they started their treatment (T1), the day human chorionic gonadotropin was administered (T2), and 4 days after the embryo transfer (T3), self-designed questionnaires, the Self-Rating Anxiety Scale, and the Self-Rating Depression Scale were completed to investigate anxiety and depression in different stages. RESULTS: Age had an effect on the anxiety and depression in women. Male infertility type and the cause of infertility had an effect on the anxiety and depression in men. The incidence of anxiety in women in the T1, T2, and T3 stages was 29.96%, 44.94%, and 17.81%, respectively. The anxiety scores of women were 46.14 ± 8.37, 50.83 ± 8.50, and 44.09 ± 8.17, respectively, which were significantly higher than those of men (p < 0.05). The anxiety score in stage T2 was the highest in women, and the depression score of women in stage T1 was the highest. The incidence of anxiety in men in the T1, T2, and T3 stages was 20.65%, 8.50%, and 6.07%, respectively. The incidence of anxiety was not significantly different in diverse stages (p > 0.05), and the same result was obtained for the incidence of depression. The anxiety and depression scores of the infertile couples in different stages were not related to the outcome of IVF-ET. CONCLUSION: The incidence of anxiety and depression in infertile couples in diverse stages of IVF-ET is different, especially in women, and the anxiety and depression of infertile couples in the process of IVF-ET may not be related to the outcome of assisted pregnancy.

7.
J Neurosci ; 39(23): 4624-4630, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30926745

RESUMO

Temporal lobe epilepsy (TLE) is a common and commonly devastating form of human epilepsy for which only symptomatic therapy is available. One cause of TLE is an episode of de novo prolonged seizures [status epilepticus (SE)]. Understanding the molecular signaling mechanisms by which SE transforms a brain from normal to epileptic may reveal novel targets for preventive and disease-modifying therapies. SE-induced activation of the BDNF receptor tyrosine kinase, TrkB, is one signaling pathway by which SE induces TLE. Although activation of TrkB signaling promotes development of epilepsy in this context, it also reduces SE-induced neuronal death. This led us to hypothesize that distinct signaling pathways downstream of TrkB mediate the desirable (neuroprotective) and undesirable (epileptogenesis) consequences. We subsequently demonstrated that TrkB-mediated activation of phospholipase Cγ1 is required for epileptogenesis. Here we tested the hypothesis that the TrkB-Shc-Akt signaling pathway mediates the neuroprotective consequences of TrkB activation following SE. We studied measures of molecular signaling and cell death in a model of SE in mice of both sexes, including wild-type and TrkBShc/Shc mutant mice in which a point mutation (Y515F) of TrkB prevents the binding of Shc to activated TrkB kinase. Genetic disruption of TrkB-Shc signaling had no effect on severity of SE yet partially inhibited activation of the prosurvival adaptor protein Akt. Importantly, genetic disruption of TrkB-Shc signaling exacerbated hippocampal neuronal death induced by SE. We conclude that therapies targeting TrkB signaling for preventing epilepsy should spare TrkB-Shc-Akt signaling and thereby preserve the neuroprotective benefits.SIGNIFICANCE STATEMENT Temporal lobe epilepsy (TLE) is a common and devastating form of human epilepsy that lacks preventive therapies. Understanding the molecular signaling mechanisms underlying the development of TLE may identify novel therapeutic targets. BDNF signaling thru TrkB receptor tyrosine kinase is one molecular mechanism promoting TLE. We previously discovered that TrkB-mediated activation of phospholipase Cγ1 promotes epileptogenesis. Here we reveal that TrkB-mediated activation of Akt protects against hippocampal neuronal death in vivo following status epilepticus. These findings strengthen the evidence that desirable and undesirable consequences of status epilepticus-induced TrkB activation are mediated by distinct signaling pathways downstream of this receptor. These results provide a strong rationale for a novel therapeutic strategy selectively targeting individual signaling pathways downstream of TrkB for preventing epilepsy.


Assuntos
Proteínas Hedgehog/metabolismo , Hipocampo/metabolismo , Glicoproteínas de Membrana/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Proteínas Tirosina Quinases/fisiologia , Células Receptoras Sensoriais/fisiologia , Estado Epiléptico/metabolismo , Animais , Sítios de Ligação , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Hipocampo/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mecanotransdução Celular , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Mutagênese Sítio-Dirigida , Fatores de Crescimento Neural/farmacologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fosforilação , Mutação Puntual , Ligação Proteica/genética , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Proteínas Recombinantes/metabolismo , Células Receptoras Sensoriais/efeitos dos fármacos , Estado Epiléptico/genética , Tato/fisiologia
8.
Rev Sci Instrum ; 90(12): 124709, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31893787

RESUMO

As one of the key components of an electromagnetic pulse simulator, the peaking capacitor is coaxially constructed with a laminate structure utilizing alternative thin metal rings and polymer film dielectrics, which is designed as a part of the antenna. This paper presents a coaxial film capacitor with a novel structure to improve its flashover performance. First, the relationship between the capacitance and the capacitor's structural parameters are deduced, and a theoretical basis of lengthening the polymer film dielectrics to enhance the flashover performance is discussed. Based on the theoretical analysis, two 150 pF, 3-layer coaxial film capacitors with different extended lengths for the polymer film dielectrics (10 and 60 mm) are designed and developed. For the capacitor with a 60 mm extended film dielectric, the polymethylmethacrylate rings are adhered to the thin metal rings to support the polymer film dielectrics using a soft adhesive. Electric field analyses show that a longer extended length could decrease the surface field at the edge of the polymer film dielectric by as much as 93%. Comparative insulation experiments show that the flashover voltage for the improved capacitor is 89.9% higher than the original one. The influence of the capacitor's polymer extensions (including the polymer supporting rings and the film dielectrics) on the radiating field of a cone antenna is analyzed numerically, and the results show that only slight changes are introduced into the radiating field. Finally, a designed 350 pF, 20-layer coaxial film capacitor with lengthened film dielectrics is presented.

9.
Antonie Van Leeuwenhoek ; 111(10): 1855-1862, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29637394

RESUMO

A Gram-stain negative, rod-shaped, non-motile, strictly aerobic bacterium HK-28T was isolated from a mangrove sediment sample in Haikou city, Hainan Province, China. Strain HK-28T was able to grow at 10-45 °C (optimum 25-30 °C), pH 5.0-8.5 (optimum 6.0-7.0) and 0.5-12.0% (w/v) NaCl (optimum 1.0-3.0%, w/v). The major cellular fatty acids were C16:0, Summed Feature 8 (C18:1 ω7c and/or C18:1 ω6c), Summed Feature 3 (C16:1 ω7c and/or C16:1 ω6c), C17:0, C12:0 3-OH and C17:1ω8c. Ubiquinone-8 (Q-8) was the predominant respiratory quinone. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, two unidentified aminophospholipids, four unidentified phospholipids, two unidentified glycolipid, an unidentified glycophospholipid, an unidentified aminolipid and an unidentified lipid. The DNA G+C content was 50.2 mol%. Accoroding to 16S rRNA gene sequence similarities, strain HK-28T shared 97.1 and 96.7% sequence similarities to the validly named species Gallaecimonas xiamenensis MCCC 1A01354T and Gallaecimonas pentaromativorans MCCC 1A06435T, respectively, and shared lower sequence similarities (< 92.0%) to all other genera. Phylogenetic analysis showed strain HK-28T was clustered with G. pentaromativorans MCCC 1A06435T and G. xiamenensis MCCC 1A01354T. Strain HK-28T showed low DNA-DNA relatedness with G. xiamenensis MCCC 1A01354T (28.3 ± 1.5%) and G. pentaromativorans MCCC 1A06435T (25.2 ± 2.4%). On the basis of phenotypic, chemotaxonomic and genotypic characteristics, strain HK-28T is considered to represent a novel species in the genus Gallaecimonas, for which the name Gallaecimonas mangrovi sp. nov. is proposed. The type strain is HK-28T (= KCTC 62177T = MCCC 1K03441).


Assuntos
Acanthaceae/microbiologia , Microbiologia Ambiental , Gammaproteobacteria/classificação , Sedimentos Geológicos/microbiologia , Gammaproteobacteria/química , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Metabolômica/métodos , Tipagem Molecular , Fenótipo , Filogenia , RNA Ribossômico 16S/genética
10.
Zhongguo Zhong Yao Za Zhi ; 43(1): 31-38, 2018 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29552808

RESUMO

The pharmacological activity of active ingredients from Chinese medicine depends greatly on the microecological environment of probiotics in the human body. After effective ingredients from traditional Chinese medicines are metabolized or biotransformed by probiotics, their metabolites can increase pharmacological activity, and can be absorbed more easily to improve the bioavailability. Therefore, the combination of Chinese medicines with probiotics is the innovation point in R&D of functional food and Chinese medicines, and also a new thinking for the modernization of Chinese medicine.This review summarizes and analyses the research progress on metabolism effects of gut microbiota on Chinese medicines components, the regulating effect of effective ingredients from Chinese medicine on intestinal probiotics, the application status of probiotics in traditional Chinese medicines, and the main problems and prospects in the research and development of Chinese medicines products with probiotic, aiming to provide theoretical guidance and practical value for the fermentation engineering of Chinese herbal medicine.


Assuntos
Medicamentos de Ervas Chinesas/metabolismo , Probióticos , Humanos , Medicina Tradicional Chinesa
11.
J Neurochem ; 140(4): 629-644, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27973753

RESUMO

Vagal Nerve Stimulation (VNS) Therapy® is a United States Food and Drug Administration approved neurotherapeutic for medically refractory partial epilepsy and treatment-resistant depression. The molecular mechanisms underlying its beneficial effects are unclear. We hypothesized that one mechanism involves neuronal activity-dependent modifications of central nervous system excitatory synapses. To begin to test this hypothesis, we asked whether VNS modifies the activity of neurons in amygdala and hippocampus. Neuronal recordings from adult, freely moving rats revealed that activity in both amygdala and hippocampus was modified by VNS immediately after its application, and changes were detected following 1 week of stimulation. To investigate whether VNS modifies the proteome of excitatory synapses, we established a label-free, quantitative liquid chromatography-tandem mass spectrometry workflow that enables global analysis of the constituents of the postsynaptic density (PSD) proteome. PSD proteins were biochemically purified from amygdala/piriform cortex of VNS- or dummy-treated rats following 1-week stimulation, and individual PSD protein levels were quantified by liquid chromatography-tandem mass spectrometry analysis. We identified 1899 unique peptides corresponding to 425 proteins in PSD fractions, of which expression levels of 22 proteins were differentially regulated by VNS with changes greater than 150%. Changes in a subset of these proteins, including significantly increased expression of neurexin-1α, cadherin 13 and voltage-dependent calcium channel α2δ1, the primary target of the antiepileptic drug gabapentin, and decreased expression of voltage-dependent calcium channel γ3, were confirmed by western blot analysis of PSD samples. These results demonstrate that VNS modulates excitatory synapses through regulating a subset of the PSD proteome. Our study reveals molecular targets of VNS and point to possible mechanisms underlying its beneficial effects, including activity-dependent formation of excitatory synapses.


Assuntos
Tonsila do Cerebelo/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Córtex Piriforme/fisiologia , Proteoma/metabolismo , Sinapses/metabolismo , Estimulação do Nervo Vago/métodos , Animais , Masculino , Neurônios/fisiologia , Proteoma/genética , Ratos , Ratos Sprague-Dawley , Sinapses/genética
12.
Neuron ; 88(3): 484-91, 2015 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-26481038

RESUMO

The BDNF receptor tyrosine kinase, TrkB, underlies nervous system function in both health and disease. Excessive activation of TrkB caused by status epilepticus promotes development of temporal lobe epilepsy (TLE), revealing TrkB as a therapeutic target for prevention of TLE. To circumvent undesirable consequences of global inhibition of TrkB signaling, we implemented a novel strategy aimed at selective inhibition of the TrkB-activated signaling pathway responsible for TLE. Our studies of a mouse model reveal that phospholipase Cγ1 (PLCγ1) is the dominant signaling effector by which excessive activation of TrkB promotes epilepsy. We designed a novel peptide (pY816) that uncouples TrkB from PLCγ1. Treatment with pY816 following status epilepticus inhibited TLE and prevented anxiety-like disorder yet preserved neuroprotective effects of endogenous TrkB signaling. We provide proof-of-concept evidence for a novel strategy targeting receptor tyrosine signaling and identify a therapeutic with promise for prevention of TLE caused by status epilepticus in humans.


Assuntos
Fragmentos de Peptídeos/uso terapêutico , Fosfolipase C gama/metabolismo , Receptor trkB/metabolismo , Estado Epiléptico/metabolismo , Estado Epiléptico/prevenção & controle , Desacopladores/uso terapêutico , Sequência de Aminoácidos , Animais , Epilepsia/genética , Epilepsia/metabolismo , Epilepsia/prevenção & controle , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Fosfolipase C gama/genética , Ratos , Ratos Sprague-Dawley , Receptor trkB/genética , Estado Epiléptico/genética
13.
Neural Regen Res ; 10(5): 778-85, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26109953

RESUMO

Abnormally increased levels of iron in the brain trigger cascade amplification in Alzheimer's disease patients, resulting in neuronal death. This study investigated whether components extracted from the Chinese herbs epimedium herb, milkvetch root and kudzuvine root could relieve the abnormal expression of iron metabolism-related protein in Alzheimer's disease patients. An APPswe /PS1ΔE9 double transgenic mouse model of Alzheimer's disease was used. The intragastric administration of compounds from epimedium herb, milkvetch root and kudzuvine root improved pathological alterations such as neuronal edema, increased the number of neurons, downregulated divalent metal transporter 1 expression, upregulated ferroportin 1 expression, and inhibited iron overload in the cerebral cortex of mice with Alzheimer's disease. These compounds reduced iron overload-induced impairment of the central nervous system, indicating a new strategy for developing novel drugs for the treatment of Alzheimer's disease.

14.
J Neurosci ; 35(23): 8866-81, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-26063919

RESUMO

We identified a family in which a translocation between chromosomes X and 14 was associated with cognitive impairment and a complex genetic disorder termed "Genetic Epilepsy and Febrile Seizures Plus" (GEFS(+)). We demonstrate that the breakpoint on the X chromosome disrupted a gene that encodes an auxiliary protein of voltage-gated Na(+) channels, fibroblast growth factor 13 (Fgf13). Female mice in which one Fgf13 allele was deleted exhibited hyperthermia-induced seizures and epilepsy. Anatomic studies revealed expression of Fgf13 mRNA in both excitatory and inhibitory neurons of hippocampus. Electrophysiological recordings revealed decreased inhibitory and increased excitatory synaptic inputs in hippocampal neurons of Fgf13 mutants. We speculate that reduced expression of Fgf13 impairs excitability of inhibitory interneurons, resulting in enhanced excitability within local circuits of hippocampus and the clinical phenotype of epilepsy. These findings reveal a novel cause of this syndrome and underscore the powerful role of FGF13 in control of neuronal excitability.


Assuntos
Epilepsia , Fatores de Crescimento de Fibroblastos/genética , Mutação/genética , Sinapses/genética , Potenciais Sinápticos/genética , Fatores Etários , Animais , Animais Recém-Nascidos , Linhagem Celular , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/genética , Modelos Animais de Doenças , Embrião de Mamíferos , Epilepsia/genética , Epilepsia/patologia , Epilepsia/fisiopatologia , Saúde da Família , Feminino , Febre/complicações , Hipocampo/patologia , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Canal de Sódio Disparado por Voltagem NAV1.1/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/fisiologia , Convulsões Febris/etiologia , Convulsões Febris/genética , Fatores Sexuais , Translocação Genética/genética , Cromossomo X/genética , Adulto Jovem
15.
Epilepsia ; 55(3): 456-63, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24502564

RESUMO

OBJECTIVE: Elucidating molecular mechanisms underlying limbic epileptogenesis may reveal novel targets for preventive therapy. Studies of TrkB mutant mice led us to hypothesize that signaling through a specific phospholipase (PLC), PLCγ1, promoted development of kindling. METHODS: To test this hypothesis, we examined the development of kindling in PLCγ1 heterozygous mice. We also examined the cellular and subcellular location of PLCγ1 in adult wild-type mice. RESULTS: The development of kindling was impaired in PLCγ1 heterozygous mice compared to wild-type controls. PLCγ1 immunoreactivity was localized to the soma and dendrites of both excitatory and inhibitory neurons in the hippocampus of adult mice. SIGNIFICANCE: This study implicates PLCγ1 signaling as the dominant pathway by which TrkB activation promotes limbic epileptogenesis. Its cellular localization places PLCγ1 in a position to modify the efficacy of both excitatory and inhibitory synaptic transmission. These findings advance PLCγ1 as a novel target for therapies aimed at preventing temporal lobe epilepsy induced by status epilepticus.


Assuntos
Hipocampo/química , Hipocampo/enzimologia , Excitação Neurológica/genética , Fosfolipase C gama/análise , Fosfolipase C gama/genética , Animais , Heterozigoto , Hipocampo/patologia , Excitação Neurológica/patologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Convulsões/genética , Convulsões/patologia , Transdução de Sinais/fisiologia
16.
Neuron ; 80(2): 429-41, 2013 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24139043

RESUMO

We analyzed four families that presented with a similar condition characterized by congenital microcephaly, intellectual disability, progressive cerebral atrophy, and intractable seizures. We show that recessive mutations in the ASNS gene are responsible for this syndrome. Two of the identified missense mutations dramatically reduce ASNS protein abundance, suggesting that the mutations cause loss of function. Hypomorphic Asns mutant mice have structural brain abnormalities, including enlarged ventricles and reduced cortical thickness, and show deficits in learning and memory mimicking aspects of the patient phenotype. ASNS encodes asparagine synthetase, which catalyzes the synthesis of asparagine from glutamine and aspartate. The neurological impairment resulting from ASNS deficiency may be explained by asparagine depletion in the brain or by accumulation of aspartate/glutamate leading to enhanced excitability and neuronal damage. Our study thus indicates that asparagine synthesis is essential for the development and function of the brain but not for that of other organs.


Assuntos
Aspartato-Amônia Ligase/deficiência , Aspartato-Amônia Ligase/genética , Encéfalo/enzimologia , Encéfalo/patologia , Predisposição Genética para Doença/genética , Microcefalia/enzimologia , Microcefalia/genética , Adolescente , Animais , Atrofia/complicações , Atrofia/enzimologia , Atrofia/genética , Criança , Feminino , Humanos , Lactente , Recém-Nascido , Deficiência Intelectual/complicações , Deficiência Intelectual/enzimologia , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Masculino , Camundongos , Camundongos Transgênicos , Microcefalia/complicações , Microcefalia/patologia , Mutação de Sentido Incorreto/genética , Linhagem , Síndrome
17.
Neuron ; 79(1): 31-8, 2013 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-23790754

RESUMO

Temporal lobe epilepsy is the most common and often devastating form of human epilepsy. The molecular mechanism underlying the development of temporal lobe epilepsy remains largely unknown. Emerging evidence suggests that activation of the BDNF receptor TrkB promotes epileptogenesis caused by status epilepticus. We investigated a mouse model in which a brief episode of status epilepticus results in chronic recurrent seizures, anxiety-like behavior, and destruction of hippocampal neurons. We used a chemical-genetic approach to selectively inhibit activation of TrkB. We demonstrate that inhibition of TrkB commencing after status epilepticus and continued for 2 weeks prevents recurrent seizures, ameliorates anxiety-like behavior, and limits loss of hippocampal neurons when tested weeks to months later. That transient inhibition commencing after status epilepticus can prevent these long-lasting devastating consequences establishes TrkB signaling as an attractive target for developing preventive treatments of epilepsy in humans.


Assuntos
Tonsila do Cerebelo/metabolismo , Epilepsia do Lobo Temporal/prevenção & controle , Hipocampo/metabolismo , Neurônios/metabolismo , Receptor trkB/genética , Estado Epiléptico/complicações , Animais , Comportamento Animal/fisiologia , Modelos Animais de Doenças , Eletroencefalografia , Epilepsia do Lobo Temporal/etiologia , Epilepsia do Lobo Temporal/genética , Ácido Caínico , Camundongos , Atividade Motora/fisiologia , Receptor trkB/metabolismo , Transdução de Sinais/genética , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/genética
18.
J Biol Chem ; 288(19): 13258-68, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23536187

RESUMO

BACKGROUND: The necessity for, or redundancy of, distinctive KChIP proteins is not known. RESULTS: Deletion of KChIP2 leads to increased susceptibility to epilepsy and to a reduction in IA and increased excitability in pyramidal hippocampal neurons. CONCLUSION: KChIP2 is essential for homeostasis in hippocampal neurons. SIGNIFICANCE: Mutations in K(A) channel auxiliary subunits may be loci for epilepsy. The somatodendritic IA (A-type) K(+) current underlies neuronal excitability, and loss of IA has been associated with the development of epilepsy. Whether any one of the four auxiliary potassium channel interacting proteins (KChIPs), KChIP1-KChIP4, in specific neuronal populations is critical for IA is not known. Here we show that KChIP2, which is abundantly expressed in hippocampal pyramidal cells, is essential for IA regulation in hippocampal neurons and that deletion of Kchip2 affects susceptibility to limbic seizures. The specific effects of Kchip2 deletion on IA recorded from isolated hippocampal pyramidal neurons were a reduction in amplitude and shift in the V½ for steady-state inactivation to hyperpolarized potentials when compared with WT neurons. Consistent with the relative loss of IA, hippocampal neurons from Kchip2(-/-) mice showed increased excitability. WT cultured neurons fired only occasional single action potentials, but the average spontaneous firing rate (spikes/s) was almost 10-fold greater in Kchip2(-/-) neurons. In slice preparations, spontaneous firing was detected in CA1 pyramidal neurons from Kchip2(-/-) mice but not from WT. Additionally, when seizures were induced by kindling, the number of stimulations required to evoke an initial class 4 or 5 seizure was decreased, and the average duration of electrographic seizures was longer in Kchip2(-/-) mice compared with WT controls. Together, these data demonstrate that the KChIP2 is essential for physiologic IA modulation and homeostatic stability and that there is a lack of functional redundancy among the different KChIPs in hippocampal neurons.


Assuntos
Potenciais de Ação , Homeostase , Proteínas Interatuantes com Canais de Kv/fisiologia , Subunidades Proteicas/fisiologia , Tonsila do Cerebelo/patologia , Tonsila do Cerebelo/fisiopatologia , Animais , Região CA1 Hipocampal/patologia , Região CA1 Hipocampal/fisiopatologia , Células Cultivadas , Estimulação Elétrica , Potenciais Pós-Sinápticos Excitadores , Técnicas In Vitro , Potenciais Pós-Sinápticos Inibidores , Excitação Neurológica , Camundongos , Camundongos da Linhagem 129 , Camundongos Transgênicos , Células Piramidais/metabolismo , Células Piramidais/fisiologia , Convulsões
19.
Int J Ophthalmol ; 5(2): 143-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22762038

RESUMO

AIM: To evaluate the efficacy of topical administration Natamycin, which is produced by China, in an experimental rabbit model of Fusarium solani keratitis, to provide experimental basis for the application of clinical safety. METHODS: Fusarium solani was induced in the right eye of 30 New Zealand rabbits. Forty-eight hours after inoculation, the animals were divided into 3 different treatment groups, 10 rabbit eyes of each group: Group 1 (Natamycin) treated with topical Natamycin, group 2 (Natacyn) treated with topical Natacyn, group 3 (control) treated with topical saline solution. The eyes of each group was examined clinically with slit lamp using ulcer scoring system on day 4, 10, 15, and 21 for status of healing, corneal vascularisation, iritis, hypopyon and macular nebula. The findings were recorded on day 10 and day 21. RESULTS: Ulcer score on day 10, day 15, day 21: The score of Natamycin group are 1.45±0.16, 1.08±0.11, 0.70±0.40. The score of Natacyn group are 1.35±0.12, 1.10±0.12, 0.65±0.35. the score of control group are 1.30±0.08, 3.63±0.28, 3.80±0.16. Natamycin group and Natacyn group were different from control group (P<0.01). There is no difference between Natamycin group and Natacyn group. Status of healing on day 10 and day 21: The cure rate of the Natamycin group is 90% on day 10, and 100% on day 21. The cure rate of the Natacyn group is 80% on day 10, and 100% on day 21.Natamycin group and Natacyn group were different from control group (P<0.01). There is no difference between Natamycin group and Natacyn group. Corneal vascularisation, iritis, hypopyon and macular nebula on day 10 and day 21: in Natamycin group, the number of the eyes which have Corner vascularisation, iritis, hypopyon and macular nebula are 2,0,0,2. In Natacyn group, the number of the eyes which have Corner vascularisation, iritis, hypopyon and macular nebula are 1,0,0,2. In control group, the number of the eyes which have Corner vascularisation, iritis, hypopyon and macular nebula are 9,9,8,9.Natamycin group and Natacyn group were different from control group (P<0.01). There is no difference between Natamycin group and Natacyn group. CONCLUSION: Natamycin was found to be effective in fungal keratitis, similar to Natacyn, and it can stop the corner vascularisation, iritis, hypopyon and macular nebula to happen. Natamyin manufactured in China is effective against fungal keratitis, with esay availability and low toxicity in its use.

20.
Int J Ophthalmol ; 5(2): 177-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22762045

RESUMO

AIM: To investigate the possible relationship between the influencing factors occurring before and during birth in full-term infants and the outcome of retinopathy. METHODS: Totally 816 full-term infants admitted in the neonate intensive unit of Boai Hospital of Zhongshan between 1 May, 2008 and 30 June, 2011 were included in the study. Fundus examination was performed and evaluated individually on them at the age of 48 hours after delivery, 2 weeks and 1 month. Some possible risk factors happening prenatally or during delivery such as pregnant related hypertension, placenta previa, placental abruption etc, as well as some neonatal risk factors such as neonatal asphyxia, hypoxic-ischemic encephalopathy (HIE), low birth weight etc, were recorded and evacuated. Then the effect of the risk factors of full-term infants on retinopathy was studied. RESULTS: The incidence of retinal hemorrhage of full-term infants with prenatal pregnant related hypertension (PRH) of the mother (43.6%) was significantly higher than that of full-term infants without (8.0%). (P<0.001). The incidence of retinal hemorrhage of full-term infants with neonatal asphyxia and /or hypoxic-ischemic encephalopathy (HIE)(29.3%) was significantly higher than that of those without (15.7%), but correlation was not found between the severity of retina hemorrhage and the degree of hypoxic disease. A pale color of optic disc was associated with a low birth weight of full-term infant. Full-term infants with birth weigh less than 2500g had a significant higher incidence of retinopathy than those with birth weight equal or more than 2500g ( P<0.001). CONCLUSION: The main influencing factors which lead to retinopathy of high risk full-term infants are prenatal factors such as PRH, and some neonatal risk factors such as asphyxia, hypoxic-ischemic encephalopathy, and low birth weight.

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