RESUMO
OBJECTIVE: T1-weighted MRI images are commonly used for volumetric assessment of brain structures. Magnetization prepared 2 rapid gradient echo (MP2RAGE) sequence offers superior gray (GM) and white matter (WM) contrast. This study aimed to quantitatively assess the agreement of whole brain tissue and deep GM (DGM) volumes obtained from MP2RAGE compared to the widely used MP-RAGE sequence. METHODS: Twenty-nine healthy participants were included in this study. All subjects underwent a 3T MRI scan acquiring high-resolution 3D MP-RAGE and MP2RAGE images. Twelve participants were re-scanned after one year. The whole brain, as well as DGM segmentation, was performed using CAT12, volBrain, and FSL-FAST automatic segmentation tools based on the acquired images. Finally, contrast-to-noise ratio between WM and GM (CNRWG), the agreement between the obtained tissue volumes, as well as scan-rescan variability of both sequences were explored. RESULTS: Significantly higher CNRWG was detected in MP2RAGE vs. MP-RAGE (Mean ± SD = 0.97 ± 0.04 vs. 0.8 ± 0.1 respectively; p<0.0001). Significantly higher total brain GM, and lower cerebrospinal fluid volumes were obtained from MP2RAGE vs. MP-RAGE based on all segmentation methods (p<0.05 in all cases). Whole-brain voxel-wise comparisons revealed higher GM tissue probability in the thalamus, putamen, caudate, lingual gyrus, and precentral gyrus based on MP2RAGE compared with MP-RAGE. Moreover, significantly higher WM probability was observed in the cerebellum, corpus callosum, and frontal-and-temporal regions in MP2RAGE vs. MP-RAGE. Finally, MP2RAGE showed a higher mean percentage of change in total brain GM compared to MP-RAGE. On the other hand, MP-RAGE demonstrated a higher overtime percentage of change in WM and DGM volumes compared to MP2RAGE. CONCLUSIONS: Due to its higher CNR, MP2RAGE resulted in reproducible brain tissue segmentation, and thus is a recommended method for volumetric imaging biomarkers for the monitoring of neurological diseases.
Assuntos
Encéfalo/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética , Substância Branca/diagnóstico por imagem , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/ultraestrutura , Encéfalo/ultraestrutura , Mapeamento Encefálico , Sistema Nervoso Central/diagnóstico por imagem , Sistema Nervoso Central/ultraestrutura , Líquido Cefalorraquidiano/metabolismo , Feminino , Substância Cinzenta/ultraestrutura , Voluntários Saudáveis , Hipocampo/diagnóstico por imagem , Hipocampo/ultraestrutura , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Manejo de Espécimes , Tálamo/diagnóstico por imagem , Tálamo/ultraestrutura , Substância Branca/ultraestruturaRESUMO
Traumatic brain injury (TBI) remains one of the leading causes of death and disability worldwide. Our previous studies have found that traditional Chinese medicine, Panax notoginseng (P. notoginseng) can reduce cerebral hemorrhage in rats with TBI. Yet, the exact mechanism still remains unclear. According to the random number table, 36 SD rats were randomly divided into six groups: Sham group (negative control group), Model group, PIK inhibitor group (positive group), P. notoginseng group (experimental group), Rapamycin group, and Panax notoginseng+Rapamycin group (experimental group). In the Model group (M group, the group showing signs of TBI without any treatment), the neural function defect score was significantly decreased, while sequestosome 1 (P62), Beclin 1, and microtubule-associated protein 1 light chain 3 (LC3-II) were significantly increased. The brain tissue was significantly damaged, and many autophagosomes were observed in the cytoplasm. Compared with the Model group and the Rapamycin group (M+Rapa group, the group showing signs of TBI with Rapamycin treatment), P62, Beclin 1, and LC3-II were significantly decreased, the score of neural function defect was significantly improved, and the brain tissue damage was significantly reduced in the PIK (phosphatidylinositol 3-kinase) inhibitor group (M+LY group, the group showing signs of TBI with PIK inhibitor treatment). Compared with the Model group, mTOR was decreased and LC3-II was increased; however, there were no significant changes in neural function defect score, HE staining, Nissl staining, and transmission electron microscopy in the Rapamycin group. Compared with the Model group, the neural function defect score at 72h was significantly improved, mTOR was significantly increased, P62, Beclin 1, and LC3-II significantly decreased, brain tissue damage was reduced in HE staining and Nissl staining, autophagosomes were reduced in cytoplasm by transmission electron microscopy in the P. notoginseng group (M+PN group, the group showing signs of TBI with P. notoginseng treatment). Also, there was no significant difference between P. notoginseng group and P. notoginseng+Rapamycin group (M+PN+Rapa group, the group showing signs of TBI with P. notoginseng+Rapamycin treatment). P. notoginseng protects the rat brain function from TBI by inhibiting autophagy through the mTOR signaling pathway and other autophagy pathways.
Assuntos
Lesões Encefálicas Traumáticas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/administração & dosagem , Panax notoginseng/química , Extratos Vegetais/administração & dosagem , Animais , Autofagia/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/fisiopatologia , Encéfalo/ultraestrutura , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/fisiopatologia , Modelos Animais de Doenças , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Ratos , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/metabolismoRESUMO
Ischemic stroke is a major health concern and a leading cause of mortality worldwide. Oxidative stress is an early event in the course of stroke inducing neuro-inflammation and cell death. Grape seed extract (GSE) is a natural phytochemical mixture exhibiting antioxidant, anti-inflammatory and neuroprotective properties. Orlistat (ORL) is an anti-obesity agent and a gastro-intestinal lipase inhibitor which showed recently beneficial effects on brain lipotoxicity. Recent studies reported the increase of lipase activity upon stroke which led us to investigate the neuroprotective effect of ORL on rat brain I/R injury as well as the putative synergism with GSE. I/R insult infarcted the brain parenchyma as assessed by TTC staining, induced an oxidative stress as revealed by increased lipoperoxidation along with alteration of antioxidant enzymes activities which was corrected using the cotreatment of ORL + GSE. I/R also disturbed the main metabolic pathways involved in brain fueling as glycolysis, neoglucogenesis, glycogenolysis, TCA cycle and electron transfer chain (ETC) complexes. These disturbances were also corrected with the cotreatment ORL + GSE which maintained energetic activities near to the control level. I/R also disrupted transition metals distribution, along with associated enzymes as tyrosinase, LDH or glutamine synthetase activities and induced hippocampal inflammation as revealed by glycogen depletion from dentate gyrus area along with depressed anti-inflammatory IL1ß cytokine and increased pro-inflammatory CD68 antigen. Interestingly almost all I/R-induced disturbances were corrected either partially upon ORL and GSE on their own and the best neuroprotection was obtained in the presence of both drugs (ORL + GSE) enabling robust neuroprotection of the sub granular zone within hippocampal dentate gyrus area.
Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Infarto Encefálico/prevenção & controle , Encéfalo/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Fármacos Neuroprotetores/farmacologia , Orlistate/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão/prevenção & controle , Animais , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Infarto Encefálico/metabolismo , Infarto Encefálico/patologia , Modelos Animais de Doenças , Quimioterapia Combinada , Mediadores da Inflamação/metabolismo , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologiaRESUMO
Alzheimer's Disease (AD) is a devastating neurodegenerative disorder without a cure. Here we show that mitochondrial respiratory chain complex I is an important small molecule druggable target in AD. Partial inhibition of complex I triggers the AMP-activated protein kinase-dependent signaling network leading to neuroprotection in symptomatic APP/PS1 female mice, a translational model of AD. Treatment of symptomatic APP/PS1 mice with complex I inhibitor improved energy homeostasis, synaptic activity, long-term potentiation, dendritic spine maturation, cognitive function and proteostasis, and reduced oxidative stress and inflammation in brain and periphery, ultimately blocking the ongoing neurodegeneration. Therapeutic efficacy in vivo was monitored using translational biomarkers FDG-PET, 31P NMR, and metabolomics. Cross-validation of the mouse and the human transcriptomic data from the NIH Accelerating Medicines Partnership-AD database demonstrated that pathways improved by the treatment in APP/PS1 mice, including the immune system response and neurotransmission, represent mechanisms essential for therapeutic efficacy in AD patients.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Pironas/uso terapêutico , Doença de Alzheimer/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuroproteção , Estudo de Prova de Conceito , Pironas/farmacologia , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND: Repeated practice to acquire expertise could result in the structural and functional changes in relevant brain circuits as a result of long-term potentiation, neurogenesis, glial genesis, and remodeling. PURPOSE: The goal of this study is to use surface-based morphology (SBM) to study cortical thickness differences in Chinese chess experts and novices, and to use regions of cortical thickness differences as seeds to guide a resting state connectivity analysis of the same population. METHODS: A raw public dataset from Huaxi MR Research Center consisting of 29 Chinese chess experts and 29 novices was used in this study, with both T1-weighted and resting state functional MRI. Surface based morphometry was performed on the T1 images with the Freesurfur pipeline, with a vertex significance threshold of p<0.05 and a cluster false discovery rate of α < 0.05. Regions with significant differences were used in a seed-based comparison of resting state functional connectivity carried out with Statistical Parameter Mapping (SPM) and the Connectivity Toolbox (CONN). Regions of connectivity differences within groups were computed with a voxel significance threshold of p<0.05 and a cluster false discovery rate of α < 0.01. RESULTS: Ten regions of the cortex of Chinese chess experts were found to be thinner than chess novices, including regions involved in visual processing, attention, working and episodic memory, and mental imagery, as well as several regions in the prefrontal cortex. There were no regions where experts' cortices were thicker than novices. Three of the thinner regions exhibited increased functional connectivity to distant brain regions in chess experts. CONCLUSIONS: Brain regions that are structurally affected by chess training are associated with processes that would likely have a high utility in chess expertise. Using a hierarchical control model, we hypothesize that the functional changes linked with some of these structural changes are related to the professionally trained chess players' ability to perceive and use contextual information, visuospatial perception, and outcome prediction in the domain of chess, all contributing to their exceptional performance.
Assuntos
Encéfalo/ultraestrutura , Cognição , Percepção , Adolescente , Adulto , Atenção , Mapeamento Encefálico , Jogos Recreativos/psicologia , Humanos , Rede Nervosa , Adulto JovemRESUMO
Epigallocatechin gallate (EGCG) is an inhibitor of DYRK1A, a serine/threonine kinase considered to be a major contributor of cognitive dysfunctions in Down syndrome (DS). Two clinical trials in adult patients with DS have shown the safety and efficacy to improve cognitive phenotypes using commercial green tea extract containing EGCG (45% content). In the present study, we performed a preclinical study using FontUp®, a new nutritional supplement with a chocolate taste specifically formulated for the nutritional needs of patients with DS and enriched with a standardized amount of EGCG in young mice overexpressing Dyrk1A (TgBACDyrk1A). This preparation is differential with previous one used, because its green tea extract has been purified to up 94% EGCG of total catechins. We analyzed the in vitro effect of green tea catechins not only for EGCG, but for others residually contained in FontUp®, on DYRK1A kinase activity. Like EGCG, epicatechin gallate was a noncompetitive inhibitor against ATP, molecular docking computations confirming these results. Oral FontUp® normalized brain and plasma biomarkers deregulated in TgBACDyrk1A, without negative effect on liver and cardiac functions. We compared the bioavailability of EGCG in plasma and brain of mice and have demonstrated that EGCG had well crossed the blood-brain barrier.
Assuntos
Encéfalo/efeitos dos fármacos , Catequina/análogos & derivados , Síndrome de Down/dietoterapia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/antagonistas & inibidores , Chá/química , Animais , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Disponibilidade Biológica , Biomarcadores/sangue , Biomarcadores/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Catequina/administração & dosagem , Catequina/efeitos adversos , Catequina/química , Catequina/uso terapêutico , Suplementos Nutricionais , Síndrome de Down/sangue , Síndrome de Down/enzimologia , Síndrome de Down/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica de Varredura , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Polifenóis/análise , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Regulação para Cima , Quinases DyrkRESUMO
INTRODUCTION: To explore the underlying mechanism of electroacupuncture (EA) treatment on central post-stroke pain (CPSP), and provide basic evidence for the EA treatment on CPSP. METHODS: Firstly, 40 male SD rats were successfully established with a model of CPSP, under the intervention of different EA frequencies (2 Hz and 15 Hz) and fluoxetine (5 ml/kg and 0.4 mg/ml), whose brain tissue was then removed for paraffin-embedded sectioning; secondly, LPS induced the primary brain cells in the hippocampus to cause inflammation model which were added NS398 (inhibitor of COX-2) and DKK-1 (inhibitor of ß-catenin) later. The lesion sites of brain tissue were observed by Nissl staining and Transmission Electron Microscope (TEM) and autophagy-related proteins (LC3B, p62, LAMP-1), COX-2 and ß-catenin were detected by Western Blot and immunohistochemical staining. Finally, the correlation between LC3B, COX-2, and ß-catenin was calculated by multispectral quantification. RESULTS: (1) In the EA group (15 Hz), the number of Nissl bodies increased, autophagy-related protein LC3B-â ¡/â , LAMP-1, COX-2, and ß-catenin was lowly expressed, p62 was highly expressed; (2) COX-2, ß-catenin and LC3B are positively correlated with each other (COX-2 & ß-catenin: r = 0.923; COX-2 & LC3B: r = 0.818; ß-catenin & LC3B: r = 0.801); (3) Nissl bodies of primary brain cells of the hippocampus under LPS were like animal experiments; after addition of DKK-1, high expression of ß-catenin and COX-2 induced by LPS was significantly down-regulated, and LC3B-II/I was significantly down-regulated, and p62 protein only had up-regulation trend; after addition of NS398, COX-2 and LC3B-II/I was significantly down-regulated. CONCLUSION: EA may inhibit autophagy in the hippocampus by reducing ß-catenin/COX-2 protein expression and effectively alleviating CPSP. SIGNIFICANCE STATEMENT: Previous studies have found that EA can reduce the expression of NK-1R in damaged rats by inhibition of COX-2 and ß-catenin loops, which controls the activation of glial cells in the damaged area and the apoptosis of neuronal cells, and alleviated pain. In the male SD rat model, we evaluated this effect that EA inhibits autophagy in the hippocampus by reducing ß-catenin/COX-2 protein expression in the brain tissue. In addition, we assessed expression levels of autophagy-related proteins and genes on the inflammatory primary brain cells model. From the experiment, we found EA may inhibit autophagy in the hippocampus by reducing ß-catenin/COX-2 protein expression. These findings provide a foundation for the interpretation of the mechanism of EA on relieving CPSP in clinical practice.
Assuntos
Autofagia , Eletroacupuntura , Hipocampo/metabolismo , Hipocampo/patologia , Dor/metabolismo , Dor/patologia , Acidente Vascular Cerebral/complicações , Animais , Astrócitos/ultraestrutura , Encéfalo/ultraestrutura , Encefalite/complicações , Encefalite/metabolismo , Masculino , Dor/etiologia , Limiar da Dor , Ratos Sprague-DawleyRESUMO
Sporadic Creutzfeldt-Jakob disease (sCJD) is a rare neurodegenerative disease that can mimic other neurological disorders. We present a case of sCJD in a 64-year-old man that presented with corticobasal syndrome and survived for 3 years. He presented initially with dementia, hemiparkinsonism and alien limb phenomenon and was diagnosed with corticobasal degeneration, ultimately progressing to immobility and akinetic mutism. With a normal MRI 1 year before onset, his neuroimaging 1 year later revealed abnormal DaTscan, cortical and hippocampal atrophy with ventricular dilatation on MRI, and diffusion-weighted cortical ribboning and thalamic hyperintensity. Postmortem, the patient's brain was collected by the Parkinson's UK Tissue Bank. Prion protein immunohistochemistry revealed widespread diffuse microvacuolar staining without kuru-type plaques. Hyperphosphorylated tau was only found in the entorhinal cortex and hippocampus. This case highlights the clinical heterogeneity of sCJD presentation and the important inclusion of CJD in the differential diagnosis of atypical presentations of neurodegenerative disease.
Assuntos
Doenças dos Gânglios da Base/diagnóstico , Síndrome de Creutzfeldt-Jakob/patologia , Degenerações Espinocerebelares/diagnóstico , Autopsia , Doenças dos Gânglios da Base/patologia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/tratamento farmacológico , Demência/diagnóstico , Diagnóstico Diferencial , Imagem de Difusão por Ressonância Magnética/métodos , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos , Proteínas Priônicas/metabolismo , Doenças Raras , Degenerações Espinocerebelares/patologia , Tálamo/diagnóstico por imagemRESUMO
Lead (Pb) is a ubiquitous environmental and industrial pollutant with worldwide health problems. The present study was designed to investigate the neurotoxic effects of Pb in albino rats and to evaluate the ameliorative role of garlic as well as Spirulina maxima against such toxic effects. Forty adult male rats were used in this investigation (10 rats/group). Group I: served as control, Group II: rats received lead acetate (100 mg/kg), Group III: rats received both lead acetate (100 mg/kg) and garlic (600 mg/kg) and Group IV: rats received both lead acetate (100 mg/kg) and spirulina (500 mg/kg) daily by oral gavage for one month. Exposure to Pb acetate adversely affected the measured acetyl cholinesterase enzyme activity, oxidative stress and lipid peroxidation parameters as well as caspase-3 gene expression in brain tissue (cerebrum and cerebellum). Light and electron microscopical examination of the cerebrum and cerebellum showed various lesions after exposure to Pb which were confirmed by immunohistochemistry. On the other hand, administration of garlic and spirulina concomitantly with lead acetate ameliorated most of the undesirable effects. It could be concluded that, the adverse effects induced by lead acetate, were markedly ameliorated by co-treatment with S. maxima more than garlic.
Assuntos
Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Caspase 3/metabolismo , Alho , Chumbo/toxicidade , Fármacos Neuroprotetores/administração & dosagem , Spirulina , Animais , Encéfalo/patologia , Encéfalo/ultraestrutura , Expressão Gênica , Masculino , Estresse Oxidativo , Extratos Vegetais/administração & dosagem , RatosRESUMO
Thiamethoxam (TMX) is a neurotoxic insecticide widely used for insect pest control. TMX and other neonicotinoids are reported to be potential causes of honey bee decline. Due to its systematic action, TMX may be recovered in pollen, bee bread, nectar, and honey, which make bees likely to be exposed to contaminated diet. In this study, we used immunolabeling to demonstrate that sublethal concentrations of TMX decrease the protein levels of synapsin in the mushroom bodies (MBs) and the antennal lobes (ALs) of pupae and newly emerged worker bees that were exposed through the food to TMX during the larval phase. A decrease in the synapsin level was observed in the MBs of pupae previously exposed to 0.001 and 1.44â¯ng/µL and in newly emerged bees previously exposed to 1.44â¯ng/µL and no changes were observed in the optical lobes (OLs). In the ALs, the decrease was observed in pupae and newly emerged bees exposed to 1.44â¯ng/µL. Because the MBs and ALs are brain structures involved in stimuli reception, learning, and memory consolidation and because synapsin is important for the regulation of neurotransmitter release, we hypothesize that exposure to sublethal concentrations of TMX during the larval stage may cause neurophysiological disorders in honey bees.
Assuntos
Abelhas/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Sinapsinas/metabolismo , Tiametoxam/toxicidade , Animais , Abelhas/crescimento & desenvolvimento , Abelhas/metabolismo , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Inseticidas/análise , Larva/metabolismo , Pólen/química , Pupa/efeitos dos fármacos , Pupa/metabolismo , Tiametoxam/análiseRESUMO
In 1873 Camillo Golgi published an article that contained the description of entire nerve cells stained in black with a new histological procedure, the black reaction. He subsequently organized all the observations made with this method in a book published in 1885. On the basis of these studies, Golgi developed a physiological model of the brain that was influenced by a holistic conception he had in mind. He named this theory diffuse nervous network, assuming that the axonal prolongations were fused (or intimately interlaced) in a diffuse web along which the nervous impulse propagated. One of the scientists who quickly understood the importance of Golgi's results was the Spanish anatomist Santiago Ramón y Cajal. However, when he studied the brain with the black reaction, he had in mind the idea of the nerve cells as independent "units" (named neurons by Waldeyer, 1891). Thus Ramón y Cajal quickly became the champion of the neuron theory that paradoxically developed thanks to the same black reaction used by Golgi for the formulation of the opposite diffuse nervous network theory. The controversy between Golgi and Ramón y Cajal represents a dramatic instance of a theory-driven perception of the same morphological evidence.
Assuntos
Encéfalo/anatomia & histologia , Imaginação , Neurônios , Neurociências/história , Fisiologia , Animais , Encéfalo/ultraestrutura , História do Século XIX , História do Século XX , Humanos , Neuroanatomia/história , Neurônios/ultraestrutura , Fisiologia/história , UltrassonografiaRESUMO
BACKGROUND: Although studies have reported an increased risk for mood disorders in Hashimoto's thyroiditis (HT) patients even in the euthyroid state, the mechanisms involved remain unclear. Neuroinflammation may play a key role in the etiology of mood disorders in humans and behavioral disturbances in rodents. Therefore, this study established a euthyroid HT model in mice and investigated whether HT itself was capable of triggering neuroinflammation accompanied by emotional alterations. METHODS: Experimental HT was induced by immunizing NOD mice with thyroglobulin and adjuvant twice. Four weeks after the last challenge, mice were tested for anxiety-like behavior in the open field and elevated plus maze tests and depression-like behavior in the forced swimming and tail suspension tests. Then, animals were sacrificed for thyroid-related parameter measure as well as detection of cellular and molecular events associated with neuroinflammation. The changes in components of central serotonin signaling were also investigated. RESULTS: HT mice showed intrathyroidal monocyte infiltration and rising serum thyroid autoantibody levels accompanied by normal thyroid function, which defines euthyroid HT in humans. These mice displayed more anxiety- and depressive-like behaviors than controls. HT mice further showed microglia and astrocyte activation in the frontal cortex detected by immunohistochemistry, real-time RT-PCR, and transmission electron microscopy (TEM). These observations were also accompanied by enhanced gene expression of proinflammatory cytokines IL-1ß and TNF-α in the frontal cortex. Despite this inflammatory response, no signs of neuronal apoptosis were visible by the TUNEL staining and TEM in the frontal cortex of HT mice. Additionally, IDO1 and SERT, key serotonin-system-related genes activated by proinflammatory cytokines, were upregulated in HT mice, accompanied by reduced frontal cortex serotonin levels. CONCLUSIONS: Our results are the first to suggest that HT induces neuroinflammation and alters related serotonin signaling in the euthyroid state, which may underlie the deleterious effects of HT itself on emotional function.
Assuntos
Sintomas Afetivos/etiologia , Encefalite/etiologia , Doença de Hashimoto/complicações , Animais , Encéfalo/patologia , Encéfalo/ultraestrutura , Proteínas de Ligação ao Cálcio/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite/patologia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Feminino , Adjuvante de Freund/toxicidade , Proteína Glial Fibrilar Ácida/metabolismo , Doença de Hashimoto/etiologia , Doença de Hashimoto/patologia , Elevação dos Membros Posteriores , Marcação In Situ das Extremidades Cortadas , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Proteínas dos Microfilamentos/metabolismo , Microscopia Eletrônica de Transmissão , Neuroglia/patologia , Neuroglia/ultraestrutura , Neurônios/patologia , Neurônios/ultraestrutura , Natação/psicologiaRESUMO
BACKGROUND: Electroacupuncture (EA) has been proved to be effective in treating certain neuropathic pain conditions. The mechanisms of pain relief by EA are not fully understood. There have been sporadic reports of damage in the peripheral nervous system (PNS) and regions of the central nervous system (CNS) at the ultrastructural level following peripheral nerve injury. However, information about possible systemic changes in the PNS and CNS after nerve injury is scarce. OBJECTIVES: The goal of this study was to examine the ultrastructural changes of the nervous system induced by a local injection of cobra venom into the sciatic nerve and to compare the ultrastructural changes in rats with or without treatment with EA or pregabalin. STUDY DESIGN: An experimental study. SETTING: Department of Anesthesiology, Pain Medicine, and Critical Care Medicine, Aviation General Hospital of China Medical University. METHODS: In this study, using an established model of sciatic neuralgia induced by local injection of cobra venom into the sciatic nerve, we examined ultrastructural changes of the PNS and CNS and how they respond to EA and pregabalin treatment. EA and pregabalin were given daily from postoperative day (POD) 14 to 36. Based on previous works, the frequency of EA stimulation of the ST36 and GB34 acupoints was held to 2/100 Hz variable. Pain sensitivity in the sciatic neuralgia rats with and without treatments was assessed using the von Frey test. Ultrastructural alterations were examined bilaterally in the prefrontal cortex, hippocampus, medulla oblongata; and the cervical, thoracic, and lumbar spinal cords on PODs 14, 40, and 60. Ultrastructural examinations were also carried out on the bilateral sciatic nerves and dorsal root ganglion (DRG) at the cervical, thoracic and lumbar levels. In rats treated with EA or pregabalin, the ultrastructure was examined on PODs 40 and 60. RESULTS: Behavioral signs of pain and systemic ultrastructural changes including demyelination were observed at all levels of the PNS and CNS in rats with sciatic neuralgia. After intervention, the mechanical withdrawal thresholds of the EA group and pregabalin group were significantly higher than that of the cobra venom group (P < 0.05). Both EA and pregabalin treatments partially reversed increased cutaneous sensitivity to mechanical stimulation. However, only the EA treatment was able to repair the ultrastructural damages caused by cobra venom. LIMITATIONS: The results confirm that peripheral nerve injury led to the ultrastructural damage at different levels of the CNS as demonstrated with electron microscopy; however, we need to further verify this at both the molecular level and in light microscope level. Sciatic neuralgia induced by cobra venom is a chemical injury, and whether this exactly mimics a peripheral nerve mechanical injury is still unclear. CONCLUSIONS: Local cobra venom injection leads to systemic neurotoxicity. EA and pregabalin alleviate pain via different mechanisms. KEY WORDS: Sciatic neuralgia, cobra venom, demyelination, electroacupuncture, pregabalin, rat model.
Assuntos
Eletroacupuntura/métodos , Neuralgia/patologia , Analgésicos/farmacologia , Animais , Encéfalo/patologia , Encéfalo/ultraestrutura , China , Venenos Elapídicos/toxicidade , Gânglios Espinais/patologia , Gânglios Espinais/ultraestrutura , Masculino , Neuralgia/induzido quimicamente , Limiar da Dor/efeitos dos fármacos , Limiar da Dor/fisiologia , Pregabalina/farmacologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/patologia , Nervo Isquiático/ultraestrutura , Medula Espinal/patologia , Medula Espinal/ultraestruturaRESUMO
Understanding the mitochondrial processes that contribute to body energy metabolism may provide an attractive therapeutic target for obesity and co-morbidities. Here we investigated whether intermittent dietary supplementation with conjugated linoleic (CLA, 18:2n-6), docosahexaenoic (22:6n-3, DHA) and eicosapentaenoic (20:5n-3, EPA) acids, either alone or in combination, changes body metabolism associated with mitochondrial functions in the brain, liver, skeletal muscle and brown adipose tissue (BAT). Male C57Bl/6 mice were divided into groups: CLA (50% cis-9, trans-11; 50% trans-10, cis-12), EPA/DHA (64% EPA; 28% DHA), CLA plus EPA/DHA or control (linoleic acid). Each mouse received 3 g/kg b.w. of the stated oil by gavage on alternating days for 60 days. Dietary supplementation with CLA or EPA/DHA increased body VO2 consumption, VCO2 production and energy expenditure, being fish oil (FO) the most potent even in combination with CLA. Individually, both oils reduced mitochondrial density in BAT. CLA supplementation alone also a) elevated the expression of uncoupling proteins in soleus, liver and hippocampus and the uncoupling activity in the last two, ad this effect was associated with reduced hydrogen peroxide production in hippocampus; b) increased proteins related to mitochondrial fission in liver. EPA/DHA supplementation alone also a) induced mitochondrial biogenesis in liver, soleus and hippocampus associated with increased expression of PGC1-α; b) induced proteins related to mitochondrial fusion in the liver, and fission and fusion in the hippocampus. Therefore, this study shows changes on mitochondrial mechanisms induced by CLA and/or EPA/DHA that can be associated with elevated body energy expenditure.
Assuntos
Ácidos Docosa-Hexaenoicos/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Ácidos Linoleicos Conjugados/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Tecido Adiposo Marrom/ultraestrutura , Animais , Encéfalo/ultraestrutura , Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Expressão Gênica/efeitos dos fármacos , Hipocampo/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Proteínas de Desacoplamento Mitocondrial/genética , Músculo Esquelético/ultraestrutura , Consumo de Oxigênio/efeitos dos fármacosRESUMO
EGb 761 is a standardized natural extract from Ginkgo biloba leaf that has shown neuroprotective effects after ischemic stroke. This study aimed to use magnetic resonance imaging (MRI) to noninvasively evaluate whether EGb 761 promotes neurovascular restoration and axonal remodeling in a rat model of focal cerebral ischemia. Male Sprague-Dawley rats were subjected to permanent right middle cerebral artery occlusion (MCAO) and treated with EGb 761 (60â¯mg/kg) or saline intragastrically once daily for 15 days starting 6â¯h after MCAO. Functional recovery was analyzed using beam walking test. Multi-parametric MRI was applied to examine the alterations of gray-white structures, intracranial vessels, cerebral perfusion and axonal integrity, and followed with histological studies. Furthermore, the protein expression of axonal remodeling related signaling pathways including protein kinase B (AKT)/ glycogen synthase kinase-3ß (GSK-3ß)/ collapsin response mediator protein 2 (CRMP2) and NogoA/NgR were detected by Western blotting analysis. Multi-parametric MRI demonstrated that EGb 761 significantly reduced infarct volume, alleviated gray and white matter damage, and enhanced collateral circulation, cerebral perfusion and axonal remodeling. Histological examinations supported the MRI results. EGb 761 treatment facilitated behavioral recovery and amplified endogenous neurogenesis. Notably, treatment with EGb 761 significantly increased the levels of p-AKT, p-GSK-3ß and decreased the expression of p-CRMP2. In addition, EGb 761 treatment up-regulated the expression of growth associated protein 43 (GAP-43) and suppressed the activation of axonal growth inhibitory molecules NogoA and NgR. These findings indicated that EGb 761 enhanced neurovascular restoration, amplified endogenous neurogenesis and promoted axonal regeneration, which in concert may contribute to gray-white matter reorganization and functional outcome after stroke.
Assuntos
Axônios/ultraestrutura , Encéfalo/diagnóstico por imagem , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Animais , Encéfalo/irrigação sanguínea , Encéfalo/ultraestrutura , Circulação Cerebrovascular/efeitos dos fármacos , Imagem de Tensor de Difusão , Modelos Animais de Doenças , Ginkgo biloba , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Neurogênese/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Ratos Sprague-Dawley , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
Reduced cerebral blood flow in Alzheimer's disease (AD) may occur in early AD, which contributes to the pathogenesis and/or pathological progression of AD. Reversing this deficit may have therapeutic potential. Certain traditional Chinese herbal medicines (e.g., Saponin and its major component Xueshuantong [XST]) increase blood flow in humans, but whether they could be effective in treating AD patients has not been tested. We found that systemic XST injection elevated cerebral blood flow in APP/PS1 transgenic mice using two-photon time-lapse imaging in the same microvessels before and after injection. Subchronic XST treatment led to improved spatial learning and memory and motor performance in the APP/PS1 mice, suggesting improved neural plasticity and functions. Two-photon time lapse imaging of the same plaques revealed a reduction in plaque size after XST treatment. In addition, western blots experiments showed that XST treatment led to reduced processing of amyloid-ß protein precursor (AßPP) and enhanced clearance of amyloid-ß (Aß) without altering the total level of AßPP. We also found increased synapse density in the immediate vicinity of amyloid plaques, suggesting enhanced synaptic function. We conclude that targeting cerebral blood flow can be an effective strategy in treating AD.
Assuntos
Doença de Alzheimer/tratamento farmacológico , Antipsicóticos/uso terapêutico , Encéfalo/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Circulação Cerebrovascular/genética , Modelos Animais de Doenças , Feminino , Humanos , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Presenilina-1/genética , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/genética , Teste de Desempenho do Rota-Rod , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Sinaptofisina/metabolismo , Fatores de TempoRESUMO
BACKGROUND: Advances in tissue clearing and molecular labeling methods are enabling unprecedented optical access to large intact biological systems. These developments fuel the need for high-speed microscopy approaches to image large samples quantitatively and at high resolution. While light sheet microscopy (LSM), with its high planar imaging speed and low photo-bleaching, can be effective, scaling up to larger imaging volumes has been hindered by the use of orthogonal light sheet illumination. RESULTS: To address this fundamental limitation, we have developed light sheet theta microscopy (LSTM), which uniformly illuminates samples from the same side as the detection objective, thereby eliminating limits on lateral dimensions without sacrificing the imaging resolution, depth, and speed. We present a detailed characterization of LSTM, and demonstrate its complementary advantages over LSM for rapid high-resolution quantitative imaging of large intact samples with high uniform quality. CONCLUSIONS: The reported LSTM approach is a significant step for the rapid high-resolution quantitative mapping of the structure and function of very large biological systems, such as a clarified thick coronal slab of human brain and uniformly expanded tissues, and also for rapid volumetric calcium imaging of highly motile animals, such as Hydra, undergoing non-isomorphic body shape changes.
Assuntos
Microscopia de Fluorescência/métodos , Animais , Encéfalo/ultraestrutura , Humanos , Hydra/ultraestruturaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Bu Shen Yi Sui capsule (BSYSC), based on traditional Chinese formula Liu Wei Di Huang pill, is effective for the treatment of multiple sclerosis (MS) in clinical experience and trials. Our previous studies confirmed that BSYSC had the neuroprotective effect in MS and its animal model, experimental autoimmune encephalomyelitis (EAE); however, its mechanism of action was not clear. Thus, the effect of BSYSC on remyelination and the underlying mechanisms were investigated in the EAE mice. MATERIALS AND METHODS: The EAE model was established by injecting subcutaneously myelin oligodendrocyte protein (MOG) 35-55 in mice. Mice were treated with BSYSC (3.02â¯g/kg) or vehicle daily by oral gavage for 40 days. The body weight and clinical score of mice were evaluated. Brain was observed by magnetic resonance imaging. The inflammation infiltrate of brain and spinal cord was determined by hematoxylin-eosin staining, while the structure of myelin sheath was visualized by transmission electron microscopy on days 23 and 40 post immunization (dpi), respectively. The protein and mRNA levels of platelets-derived growth factor receptor (PDGFR) α and 2', 3'-cyclic nucleotide-3'-phosphodiesterase (CNPase) were measured by immunohistochemistry, western blot and quantitative real-time polymerase chain reaction. The protein expressions of semaphorins (Sema) 3A, Neuropilin (NRP) -â¯1, leukemia inhibitory factor (LIF), LIF receptor (LIFR) and Nkx6.2 were further investigated by western blot. RESULTS: BSYSC treatment improved the body weight and clinical score of EAE mice, alleviated inflammatory infiltration and nerve fiber injuries. It also protected the ultrastructural integrity of myelin sheath. BSYSC significantly increased expressions of PDGFRα and CNPase in mice with EAE on 40 dpi. Furthermore, BSYSC treatment increased the expressions of LIF, LIFR and Nkx6.2 and reduced Sema3A and NRP-1 in EAE mice on 40 dpi. CONCLUSIONS: The data demonstrated that BSYSC exhibited the neuroprotective effect against EAE by promoting oligodendrocyte progenitor cells (OPCs) proliferation and differentiation, thus facilitating remyelination. Sema3A/NRP-1, LIF/LIFR and Nkx6.2 are likely contributed to the effects of BSYSC on OPCs.
Assuntos
Encéfalo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Encefalomielite Autoimune Experimental/tratamento farmacológico , Proteínas de Homeodomínio/metabolismo , Subunidade alfa de Receptor de Fator Inibidor de Leucemia/metabolismo , Fator Inibidor de Leucemia/metabolismo , Bainha de Mielina/efeitos dos fármacos , Neuropilina-1/metabolismo , Fármacos Neuroprotetores/farmacologia , Semaforina-3A/metabolismo , Medula Espinal/efeitos dos fármacos , Fatores de Transcrição/metabolismo , 2',3'-Nucleotídeo Cíclico Fosfodiesterases/metabolismo , Administração Oral , Animais , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Cápsulas , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Medicamentos de Ervas Chinesas/administração & dosagem , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Feminino , Camundongos Endogâmicos C57BL , Bainha de Mielina/metabolismo , Bainha de Mielina/ultraestrutura , Glicoproteína Mielina-Oligodendrócito , Fármacos Neuroprotetores/administração & dosagem , Células Precursoras de Oligodendrócitos/efeitos dos fármacos , Células Precursoras de Oligodendrócitos/metabolismo , Células Precursoras de Oligodendrócitos/patologia , Fragmentos de Peptídeos , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/ultraestrutura , Fatores de TempoRESUMO
OBJECTIVES: Acquired aplastic anemia (AA) is a hematopoietic stem cell disease that leads to hematopoietic disorder and peripheral blood pancytopenia. We investigated whether nutritional support is helpful to AA recovery. METHODS: We established a rat model with AA. A nutrient mixture was administered to rats with AA through different dose gavage once per day for 55 d. Animals in this study were assigned to one of five groups: normal control (NC; group includes normal rats); AA (rats with AA); high dose (AA + nutritional mixture, 2266.95 mg/kg/d); medium dose (1511.3 mg/kg/d); and low dose (1057.91 mg/kg/d). The effects of nutrition administration on general status and mitochondrial function of rats with AA were evaluated. RESULTS: The nutrient mixture with which the rats were supplemented significantly improved weight, peripheral blood parameters, and histologic parameters of rats with AA in a dose-dependent manner. Furthermore, we observed that the number of mitochondria in the liver, spleen, kidney, and brain was increased after supplementation by transmission electron microscopy analysis. Nutrient administration also improved mitochondrial DNA content, adenosine triphosphate content, and membrane potential but inhibited oxidative stress, thus, repairing the mitochondrial dysfunction of the rats with AA. CONCLUSIONS: Taken together, nutrition supplements may contribute to the improvement of mitochondrial function and play an important role in the recuperation of rats with AA.
Assuntos
Anemia Aplástica/fisiopatologia , Anemia Aplástica/terapia , Mitocôndrias/fisiologia , Apoio Nutricional/métodos , Trifosfato de Adenosina/análise , Anemia Aplástica/patologia , Animais , Encéfalo/ultraestrutura , DNA/análise , Modelos Animais de Doenças , Rim/ultraestrutura , Potencial da Membrana Mitocondrial/fisiologia , Microscopia Eletrônica de Transmissão , Mitocôndrias/química , Mitocôndrias/patologia , Mitocôndrias Hepáticas/patologia , Mitocôndrias Hepáticas/fisiologia , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Baço/ultraestruturaRESUMO
Children and adolescents have the highest rates of traumatic brain injury (TBI), with mild TBI (mTBI) accounting for most of these injuries. Adolescents are particularly vulnerable and often suffer from post-injury symptomologies that may persist for months. We hypothesized that the combination of resveratrol (RES), prebiotic fiber (PBF), and omega-3 fatty acids (docosahexaenoic acid (DHA)) would be an effective therapeutic supplement for the mitigation of mTBI outcomes in the developing brain. Adolescent male and female Sprague-Dawley rats were randomly assigned to the supplement (3S) or control condition, which was followed by a mTBI or sham insult. A behavioral test battery designed to examine symptomologies commonly associated with mTBI was administered. Following the test battery, tissue was collected from the prefrontal cortex (PFC) and primary auditory cortex for Golgi-Cox analysis of spine density, and for changes in expression of 6 genes (Aqp4, Gfap, Igf1, Nfl, Sirt1, and Tau). 3S treatment altered the behavioral performance of sham animals indicating that dietary manipulations modify premorbid characteristics. 3S treatment prevented injury-related deficits in the longer-term behavior measures, medial prefrontal cortex (mPFC) spine density, and levels of Aqp4, Gfap, Igf1, Nfl, and Sirt1 expression in the PFC. Although not fully protective, treatment with the supplement significantly improved post-mTBI function and warrants further investigation.