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1.
Eur J Pharmacol ; 978: 176792, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38950834

RESUMO

The lithium-pilocarpine model is commonly used to recapitulate characteristics of human intractable focal epilepsy. In the current study, we explored the impact of topiramate (TPM) alone and in combination with pregabalin and lacosamide administration for 6 weeks on the evolution of spontaneous recurrent seizures (SRS) and disease-modifying potential on associated neuropsychiatric comorbidities. In addition, redox impairments and neurodegeneration in hippocampus regions vulnerable to temporal lobe epilepsy (TLE) were assessed by cresyl violet staining. Results revealed that acute electrophysiological (EEG) profiling of the ASD cocktail markedly halted sharp ictogenic spikes as well as altered dynamics of brain wave oscillations thus validating the need for polytherapy vs. monotherapy. In TLE animals, pharmacological intervention for 6 weeks with topiramate 10 mg/kg in combination with PREG and LAC at the dose of 20 mg/kg exhibited marked protection from SRS incidence, improved body weight, offensive aggression, anxiety-like behavior, cognitive impairments, and depressive-like behavior (p < 0.05). Moreover, combination therapy impeded redox impairments as evidenced by decreased MDA and AchE levels and increased activity of antioxidant SOD, GSH enzymes. Furthermore, polytherapy rescued animals from SE-induced neurodegeneration with increased neuronal density in CA1, CA3c, CA3ab, hilus, and granular cell layer (GCL) of the dentate gyrus. In conclusion, early polytherapy with topiramate in combination with pregabalin and lacosamide prompted synergy and prevented epileptogenesis with associated psychological and neuropathologic alterations.


Assuntos
Modelos Animais de Doenças , Eletroencefalografia , Lacosamida , Fármacos Neuroprotetores , Pregabalina , Topiramato , Animais , Lacosamida/farmacologia , Lacosamida/uso terapêutico , Topiramato/farmacologia , Topiramato/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Masculino , Pregabalina/farmacologia , Pregabalina/uso terapêutico , Ratos , Comportamento Animal/efeitos dos fármacos , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Quimioterapia Combinada , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Hipocampo/patologia , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/fisiopatologia , Ratos Wistar , Epilepsia do Lobo Temporal/tratamento farmacológico , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/induzido quimicamente
2.
Exp Gerontol ; 177: 112198, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37150330

RESUMO

Senescence-accelerated mouse prone 8 (SAMP8) mice exhibit cognitive defects and neuron loss with aging, and were used to study anti-aging effects of Dendrobium nobile alkaloids (DNLA). DNLA (20 and 40 mg/kg) were orally administered to SAMP8 mice from 6 to 10 months of age. At 10-month of age, behavioral tests via Y-maze and Open-field and neuron damage via Nissl staining were evaluated. Protein was extracted and subjected to phosphorylated proteomic analysis followed by bioinformatic analysis. The cognitive deficits and neuron loss in hippocampus and cortex of aged SAMP8 mice were improved by DNLA. Hippocampal proteomic analysis revealed 196 differentially expressed protein/genes in SAMP8 compared to age-matched senescence-accelerated resistant SAMR1 mice. Gene Oncology enriched the tubulin binding, microtubule binding, and other activities. Kyoto Encyclopedia of Genes and Genomes (KEGG) revealed endocytosis, mRNA surveillance, tight junction, protein processing in endoplasmic reticulum, aldosterone synthesis and secretion, and glucagon signaling pathway changes. Upregulated protein/genes in the hippocampus of SAMP8 mice, such as Lmtk3, Usp10, Dzip1, Csnk2b, and Rtn1, were attenuated by DNLA; whereas downregulated protein/genes, such as Kctd16, Psd3, Bsn, Atxn2l, and Kif1a, were rescued by DNLA. The aberrant protein/gene expressions of SAMP8 mice were correlated with transcriptome changes of Alzheimer's disease in the Gene Expression Omnibus (GEO) database, and the scores were attenuated by DNLA. Thus, DNLA improved cognitive dysfunction and ameliorated neuronal injury in aged SAMP8 mice, and attenuated aberrant protein/gene expressions.


Assuntos
Alcaloides , Doença de Alzheimer , Dendrobium , Camundongos , Animais , Proteômica , Alcaloides/farmacologia , Envelhecimento , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Hipocampo
3.
Front Vet Sci ; 10: 1101024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876003

RESUMO

In this study, we describe in detail the anatomy of nuclei involved in seasonal fertility regulation (SFR) in ewes. For this purpose, the intergeniculate leaflet of the visual thalamus, the caudal hypothalamic arcuate nucleus, and suprachiasmatic, paraventricular and supraoptic nuclei of the rostral hypothalamus were morphometrically and qualitatively analyzed in Nissl-stained serial sections, in the three anatomical planes. In addition, data were collected on calcium-binding proteins and cell phenotypes after immunostaining alternate serial sections for calretinin, parvalbumin and calbindin. For a complete neuroanatomical study, glial architecture was assessed by immunostaining and analyzing alternate sections for glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule 1 (IBA1). The results showed a strong microglial and astroglia reaction around the hypothalamic nuclei of interest and around the whole 3rd ventricle of the ewe brain. Moreover, we correlated cytoarchitectonic coordinates of panoramic serial sections with their macroscopic localization and extension in midline sagittal-sectioned whole brain to provide guidelines for microdissecting nuclei involved in SFR.

4.
Anat Sci Int ; 98(1): 36-42, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35569088

RESUMO

The degu (Octodon degus) is a rodent that normally constructs burrows for nesting and rearing. To navigate inside these burrows, degus may use idiothetic and/or sensory cues more than visual information, which is less effective in burrows. Spatial information for navigation is processed in several key brain regions including the retrosplenial cortex (RS). However, the structural characteristics of the degu RS have not been previously reported. The present study measured the sizes of the RS and constituent areas 29 and 30 in the degu, and compared these to those found in the rat, which is a terrestrial rodent. The proportion of the rostrocaudal length of the entire RS relative to that of the entire cortex was significantly larger in degus versus rats. The proportion of the rostrocaudal length of the RS at levels rostral to the splenium of the corpus callosum relative to that of the entire cortex was also significantly larger in degus versus rats. Furthermore, the ratio of the estimated volume of area 29 relative to that of area 30 was significantly larger in degus versus rats. These results show that the degu has a rostrocaudally longer rostral RS with a larger area 29 compared to the rat, which suggests that these structural features may be relevant to differences in spatial information processing between the fossorial degu and terrestrial rat.


Assuntos
Octodon , Ratos , Animais , Ratos Wistar , Giro do Cíngulo , Roedores , Encéfalo
5.
Front Neuroanat ; 16: 940993, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312299

RESUMO

Despite a rapid growth in the application of modern techniques for visualization studies in life sciences, the classical methods of histological examination are yet to be outdated. Herein, we introduce a new approach that involves combining silver nitrate pretreatment and impregnation with consequent Nissl (cresyl violet) staining for cortex and striatum architectonics study on the same microscopy slide. The developed approach of hybrid staining provides a high-quality visualization of cellular and subcellular structures, including impregnated neurons (about 10%), Nissl-stained neurons (all the remaining ones), and astrocytes, as well as chromatophilic substances, nucleoli, and neuropil in paraffin sections. We provide a comparative study of the neuronal architectonics in both the motor cortex and striatum based on the differences in their tinctorial properties. In addition to a comparative study of the neuronal architectonics in both the motor cortex and striatum, the traditional methods to stain the cortex (motor and piriform) and the striatum are considered. The proposed staining approach compiles the routine conventional methods for thin sections, expanding avenues for more advanced examination of neurons, blood-brain barrier components, and fibers both under normal and pathological conditions. One of the main hallmarks of our method is the ability to detect changes in the number of glial cells. The results of astrocyte visualization in the motor cortex obtained by the developed technique agree well with the alternative studies by glial fibrillary acidic protein (GFAP) immunohistochemical reaction. The presented approach of combined staining has great potential in current histological practice, in particular for the evaluation of several neurological disorders in clinical, pre-clinical, or neurobiological animal studies.

6.
J Ethnopharmacol ; 293: 115199, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35346813

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Bacopa monnieri (BM) is commonly employed in the Indian traditional system of medicines, i.e. Ayurveda as a memory booster, antioxidant, anti-inflammatory, antipyretic, analgesic, sedative and anti-epileptic for decades. AIM OF THE STUDY: To evaluate the neuroprotective effect of Bacopa monnieri (BM) in experimental model of autism spectrum disorder (ASD) in Wistar rats and explore its mechanism of action. MATERIALS AND METHODS: BacoMind, was evaluated for its neuroprotective effect in valproic acid (VPA) model of ASD. For in-vivo study, the pregnant female Wistar rats were divided in two groups; normal control (NC) and VPA group who received single dose of normal saline (0.9%) or 600 mg/kg dose of VPA respectively on gestation day (G.D) 12.5. After the birth, all pups were segregated according to the sex. All the male pups from the dams were divided into six groups: Group 1 (NC, treated with only 0.9% normal saline, group 2 (VPA, treated 600 mg/kg on G.D12.5 and normal saline from post natal day (PND) 23 to 43), group 3 (risperidone 2.5 mg/kg, PND 23 to 43) and groups 4, 5 and 6 (BM 20, 40, 80 mg/kg, PND 23 to 43). All experimental groups were subjected to batteries of behavior parameters (three chamber sociability test, Morris Water Maze, elevated plus maze, open field and rota rod test), biochemical parameters such as oxidative stress (GSH, SOD, Catalase, MDA), inflammatory cytokines (Il-1ß, IL-6, IL-10, TNF-α), histopathological examination (cresyl violet staining) of hippocampus (HC) and prefrontal cortex (PFC) regions. Further, the mRNA as well as protein expression of AMPA receptor was evaluated using RT-PCR and western blot respectively to study the mechanism of neuroprotective effect of BM. The in-silico analysis followed evaluating the binding profile of different constituents of BacoMind with AMPA receptor. RESULTS: The results of the in-vivo study indicated BM at 80 mg/kg ameliorated abnormal behavioral paradigms such as social deficits, repetitive behavior, learning and memory impairments, and motor coordination exhibited by the VPA model of ASD in rats. Furthermore, BM was found to have a significant anti-oxidant (increasing GSH, SOD, and catalase and decreasing MDA levels) and anti-inflammatory properties (decreasing IL-1ß, 6, TNF- α). The histopathological score was also found to be significantly improved by BM in a dose dependent manner in both HC and PFC. In addition to this, the up-regulated mRNA as well as protein expression of AMPA receptor was significantly reduced by 80 mg/kg dose of BM in both HC and PFC. Further, the in-silico analysis of different constituents of BacoMind with AMPA receptor demonstrated that luteolin and apigenin showed good binding to both the competitive antagonist binding site, non-competitive antagonist binding site and allosteric modulator site while Bacosaponin C showed good binding to the non-competitive antagonist binding site. CONCLUSION: The present study concluded that BM can be a potential candidate for ameliorating the ASD symptoms in rats and acts via modulating the up-regulated AMPA receptor expression.


Assuntos
Transtorno do Espectro Autista , Bacopa , Fármacos Neuroprotetores , Efeitos Tardios da Exposição Pré-Natal , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/tratamento farmacológico , Bacopa/química , Catalase , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Gravidez , RNA Mensageiro , Ratos , Ratos Wistar , Receptores de AMPA , Solução Salina , Superóxido Dismutase , Ácido Valproico/farmacologia
7.
Neural Regen Res ; 17(8): 1827-1832, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35017445

RESUMO

Targeted muscle reinnervation (TMR) is a surgical procedure used to transfer residual peripheral nerves from amputated limbs to targeted muscles, which allows the target muscles to become sources of motor control information for function reconstruction. However, the effect of TMR on injured motor neurons is still unclear. In this study, we aimed to explore the effect of hind limb TMR surgery on injured motor neurons in the spinal cord of rats after tibial nerve transection. We found that the reduction in hind limb motor function and atrophy in mice caused by tibial nerve transection improved after TMR. TMR enhanced nerve regeneration by increasing the number of axons and myelin sheath thickness in the tibial nerve, increasing the number of anterior horn motor neurons, and increasing the number of choline acetyltransferase-positive cells and immunofluorescence intensity of synaptophysin in rat spinal cord. Our findings suggest that TMR may enable the reconnection of residual nerve fibers to target muscles, thus restoring hind limb motor function on the injured side.

8.
Acta Radiol ; 62(12): 1666-1673, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33287549

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a severe central nervous system injury that can generally induce different degrees of sensory and motor dysfunction. PURPOSE: To clarify the changes of diffusion tensor imaging (DTI) parameters after spinal cord myelotomy in rats with SCI. MATERIAL AND METHODS: Eighteen Sprague Dawley (SD) rats were randomly divided into the Sham group (n=6), SCI group (n=6), and Mye group (n=6), respectively. The DTI values at 1, 3, 7, and 21 days after modeling were collected by magnetic resonance imaging (MRI). The spinal specimen at the injury site was collected on the 21st day for Nissl's staining to assess the changes in neurons. RESULTS: The fractional anisotropy (FA) values in both the SCI group and Mye group significantly decreased. In addition, the FA values between the two groups were statistically significant (P < 0.001). The apparent diffusion coefficient (ADC), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) values all decreased and then increased (P < 0.001). Pearson correlation test showed that the ADC, MD, and AD values were positively correlated with the Basso Beattie Bresnahan (BBB) score. Nissl's staining showed a higher number of Nissl's bodies, and deep staining of Nissl's bodies in the Mye group, while the morphology of neurons was relatively good. The number of neurons in the Mye group was significantly higher after myelotomy compared to the SCI group (P < 0.001). CONCLUSION: The DTI parameters, especially ADC values, could non-invasively and quantifiably evaluate the efficacy of myelotomy for rats with SCI.


Assuntos
Imagem de Tensor de Difusão/métodos , Traumatismos da Medula Espinal/diagnóstico por imagem , Medula Espinal/cirurgia , Animais , Anisotropia , Corpos de Nissl , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/fisiopatologia , Coloração e Rotulagem , Fatores de Tempo , Resultado do Tratamento
9.
CNS Neurol Disord Drug Targets ; 19(4): 276-289, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32496993

RESUMO

BACKGROUND: Studies have found that autophagy could promote the clearance of Aß. To promote and maintain the occurrence of autophagy in Alzheimer's Disease (AD) might be a potential way to reduce neuronal loss and improve the learning and memory of AD. OBJECTIVE: To investigate the possible mechanisms of Yishen Huazhuo Decoction (YHD) against AD model. METHODS: Forty 7-month-old male SAMP8 mice were randomly divided into model (P8) group and YHD group, 20 in each group, with 20 SAMR1 mice as control (R1) group. All mice were intragastrically administered for 4 weeks, YHD at the dosage of 6.24g/kg for YHD group, and distilled water for P8 group and R1 group. Morris Water Maze (MWM) test, Nissl's staining, TEM, TUNEL staining, immunofluorescence double staining, and western blot analysis were applied to learning and memory, structure and ultrastructure of neurons, autophagosome, apoptosis index, Aß, LAMP1, and autophagy related proteins. RESULTS: The escape latency time of YHD group was significantly shorter on the 4th and 5th day during MWM test than those in P8 group (P=0.011, 0.008<0.05), and the number of crossing platform in YHD group increased significantly (P=0.02<0.05). Nissl's staining showed that the number of neurons in YHD group increased significantly (P<0.0001). TEM showed in YHD group that the nucleus of neurons was slightly irregular, with slightly reduced organelles, partially fused and blurred cristae and membrane of mitochondria. The apoptosis index of YHD group showed a decreasing trend, without statistically significant difference (P=0.093>0.05), while Caspase3 expression in YHD group was significantly lower (P=0.044<0.05). YHD could promote the clearance of Aß1-42 protein, improve the expression of Beclin-1 and p-Bcl2 proteins, reduce mTOR and p62 proteins. CONCLUSION: YHD could induce autophagy initiation, increase the formation of autophagosomes and autolysosome, promote the degradation of autophagy substrates, thereby regulating autophagy, and promoting the clearance of Aß1-42 to improve memory impairment in SAMP8 mice.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Neurônios/efeitos dos fármacos , Fragmentos de Peptídeos/efeitos dos fármacos , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagossomos/patologia , Autofagossomos/ultraestrutura , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Aprendizagem/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/patologia , Lisossomos/ultraestrutura , Memória/efeitos dos fármacos , Camundongos , Teste do Labirinto Aquático de Morris , Neurônios/metabolismo , Neurônios/patologia , Neurônios/ultraestrutura , Fragmentos de Peptídeos/metabolismo
10.
Front Neurosci ; 14: 322, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351352

RESUMO

Mapping the cytoarchitecture of the whole brain can reveal the organizational logic of neural systems. However, this remains a significant challenge, especially for gyrencephalic brains with a large volume. Here we propose an integrated pipeline for generating a cytoarchitectonic atlas with single-cell resolution of the whole brain. To analyze a large-volume brain, we used a modified en-bloc Nissl staining protocol to achieve uniform staining of large-scale brain specimens from ferret (Mustela putorius furo). By combining whole-brain imaging and big data processing, we established strategies for parsing cytoarchitectural information at a voxel resolution of 0.33 µm × 0.33 µm × 1 µm and terabyte-scale data analysis. Using the cytoarchitectonic datasets for adult ferret brain, we identified giant pyramidal neurons in ferret brains and provide the first report of their morphological diversity, neurochemical phenotype, and distribution patterns in the whole brain in three dimensions. This pipeline will facilitate studies on the organization and development of the mammalian brains, from that of rodents to the gyrencephalic brains of ferret and even primates.

11.
Med Biol Eng Comput ; 58(5): 1127-1146, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32189205

RESUMO

The automatic cell analysis method is capable of segmenting the cells and can detect the number of live/dead cells present in the body. This study proposed a novel non-linear segmentation model (NSM) for the segmentation and quantification of live/dead cells present in the body. This work also reveals the aspects of electromagnetic radiation on the cell body. The bright images of the hippocampal CA3 region of the rat brain under the resolution of 60 × objective are used to analyze the effects called NISSL-stained dataset. The proposed non-linear segmentation model segments the foreground cells from the cell images based on the linear regression analysis. These foreground cells further get discriminated as live/dead cells and quantified using shape descriptors and geometric method, respectively. The proposed segmentation model is showing promising results (accuracy, 82.82%) in comparison with the existing renowned approaches. The counting analysis of live and dead cells using the proposed method is far better than the manual counts. Therefore, the proposed segmentation model and quantifying procedure is an amalgamated method for cell quantification that yields better segmentation results and provides pithy insights into the analysis of neuronal anomalies at a microscopic level. Graphical Abstract Resultant View of the overall proposed approach.


Assuntos
Região CA3 Hipocampal , Processamento de Imagem Assistida por Computador/métodos , Microscopia/métodos , Algoritmos , Animais , Encéfalo/citologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Região CA3 Hipocampal/citologia , Região CA3 Hipocampal/diagnóstico por imagem , Região CA3 Hipocampal/patologia , Morte Celular , Sobrevivência Celular , Dinâmica não Linear , Ratos
13.
Neural Regen Res ; 15(7): 1350-1359, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31960824

RESUMO

Interleukin 17 (IL-17) and its main producer, T cell receptor γδ cells, have neurotoxic effects in the pathogenesis of intracerebral hemorrhage (ICH), aggravating brain injuries. To investigate the correlation between IL-17 and ICH, we dynamically screened serum IL-17 concentrations using enzyme-linked immunosorbent assay and explored the clinical values of IL-17 in ICH patients. There was a significant negative correlation between serum IL-17 level and neurological recovery status in ICH patients (r = -0.498, P < 0.01). To study the neurotoxic role of IL-17, C57BL/6 mice were used to establish an ICH model by injecting autologous blood into the caudate nucleus. Subsequently, the mice were treated with mouse neural stem cells (NSCs) and/or IL-17 neutralizing antibody for 72 hours. Flow cytometry, brain water content detection, Nissl staining, and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling results indicated that NSC transplantation significantly reduced IL-17 expression in peri-hematoma tissue, but there was no difference in T cell receptor γδ cells. Compared with the ICH group, there were fewer apoptotic bodies and more Nissl bodies in the ICH + NSC group and the ICH + NSC + IL-17 group. To investigate the potential effect of IL-17 on directional differentiation of NSCs, we cultured mouse NSCs (NE-4C) alone or co-cultured them with T cell receptor γδ cells, which were isolated from mouse peripheral blood mononuclear cells, for 7 days. The results of western blot assays revealed that IL-17 secreted by T cell receptor γδ cells reduced the differentiation of NSCs into astrocytes and neurons, while IL-17 neutralization relieved the inhibition of directional differentiation into astrocytes rather than neurons. In conclusion, serum IL-17 levels were elevated in the early stage of ICH and were negatively correlated with outcome in ICH patients. Animal experiments and cytological investigations therefore demonstrated that IL-17 probably has neurotoxic roles in ICH because of its inhibitory effects on the directional differentiation of NSCs. The application of IL-17 neutralizing antibody may promote the directional differentiation of NSCs into astrocytes. This study was approved by the Clinical Research Ethics Committee of Anhui Medical University of China (For human study: Approval No. 20170135) in December 2016. All animal handling and experimentation were reviewed and approved by the Institutional Animal Care and Use Committee of Anhui Medical University (approval No. 20180248) in December 2017.

14.
Pharmacol Biochem Behav ; 188: 172834, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31785244

RESUMO

Aerobic exercise has been associated with hippocampal plasticity, both in healthy adults and in psychosis patients, but its impact on cortical regions remains unclear. The entorhinal cortex serves as a critical gateway for the hippocampus, and recent studies suggest that this region may also be impacted following an exercise regime. In order to investigate the effects of antipsychotic medications and exercise on the entorhinal cortex, female rats were chronically administered either olanzapine or vehicle and were either sedentary or had access to a running wheel for 9 weeks. Olanzapine-treated rats had decreased medial entorhinal cortical thickness compared to vehicle-treated rats. A statistically significant interaction was observed for layer II of the entorhinal cortex, with exercising rats having significantly greater thickness compared to sedentary rats in the vehicle group, but not the olanzapine group. Greater total entorhinal and lateral entorhinal cortical thickness was associated with greater average activity. In exercising rats, decreasing glucose intolerance was associated with larger total entorhinal and layer II cortical thickness. Lower fasting insulin levels were associated with greater total entorhinal, lateral entorhinal, and layer II cortical thickness. The relationship between increased activity and greater entorhinal cortical thickness was mediated by reduced fasting insulin, indicating that regulation of metabolic risk factors may contribute to impact of aerobic exercise on the entorhinal cortex. Aerobic exercise may be helpful in counteracting metabolic side effects of antipsychotic medications and managing these side effects may be key to promoting entorhinal cortical plasticity in patients treated with second-generation antipsychotic drugs.


Assuntos
Antipsicóticos/toxicidade , Espessura Cortical do Cérebro , Córtex Entorrinal/efeitos dos fármacos , Córtex Entorrinal/metabolismo , Olanzapina/toxicidade , Condicionamento Físico Animal/fisiologia , Animais , Córtex Entorrinal/patologia , Feminino , Condicionamento Físico Animal/psicologia , Ratos , Ratos Sprague-Dawley , Comportamento Sedentário
15.
J Anat ; 235(3): 651-669, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31435943

RESUMO

Von Economo neurons (VENs) are modified pyramidal neurons characterized by an extremely elongated rod-shaped soma. They are abundant in layer V of the anterior cingulate cortex (ACC) and fronto-insular cortex (FI) of the human brain, and have long been described as a human-specific neuron type. Recently, VENs have been reported in the ACC of apes and the FI of macaque monkeys. The first description of the somato-dendritic morphology of VENs in the FI by Cajal in 1899 (Textura del Sistema Nervioso del Hombre y de los Vertebrados, Tomo II. Madrid: Nicolas Moya) strongly suggested that they were a unique neuron subtype with specific morphological features. It is surprising that a clarification of this extremely important observation has not yet been attempted, especially as possible misidentification of other oval or fusiform cells as VENs has become relevant in many recently published studies. Here, we analyzed sections of Brodmann area 24 (ACC) stained with rapid Golgi and Golgi-Cox in five adult human specimens, and confirmed Cajal's observations. In addition, we established a comprehensive morphological description of VENs. VENs have a distinct somato-dendritic morphology that allows their clear distinction from other modified pyramidal neurons. We established that VENs have a perpendicularly oriented, stick-shaped core part consisting of the cell body and two thick extensions - an apical and basal stem. The perpendicular length of the core part was 150-250 µm and the thickness was 10-21 µm. The core part was characterized by a lack of clear demarcation between the cell body and the two extensions. Numerous thin, spiny and horizontally oriented side dendrites arose from the cell body. The basal extension of the core part typically ended by giving numerous smaller dendrites with a brush-like branching pattern. The apical extension had a topology typical for apical dendrites of pyramidal neurons. The dendrites arising from the core part had a high dendritic spine density. The most distinct feature of VENs was the distant origin site of the axon, which arose from the ending of the basal extension, often having a common origin with a dendrite. Quantitative analysis found that VENs could be divided into two groups based on total dendritic length - small VENs with a peak total dendritic length of 1500-2500 µm and large VENs with a peak total dendritic length of 5000-6000 µm. Comparative morphological analysis of VENs and other oval and fusiform modified pyramidal neurons showed that on Nissl sections small VENs might be difficult to identify, and that oval and fusiform neurons could be misidentified as VENs. Our analysis of Golgi slides of Brodmann area 9 from a total of 32 adult human subjects revealed only one cell resembling VEN morphology. Thus, our data show that the numerous recent reports on the presence of VENs in non-primates in other layers and regions of the cortex need further confirmation by showing the dendritic and axonal morphology of these cells. In conclusion, our study provides a foundation for further comprehensive morphological and functional studies on VENs between different species.


Assuntos
Giro do Cíngulo/citologia , Células Piramidais/citologia , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Coloração e Rotulagem
16.
Neuropharmacology ; 144: 193-207, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30366002

RESUMO

Schizophrenia is a debilitating disorder with complex and unclarified etiological factors. Sex differences have been observed in humans but animal models have only focused on male subjects. In this study, we report the establishment of the neurodevelopmental MAM model of schizophrenia in mice and compare the schizotypic-like characteristics and cognitive functions in both sexes. Pregnant mice were injected with methylazoxymethanol acetate (MAM) or saline on gestational day (GD) 16 (MAM-16) or 17 (MAM-17). Female MAM-16, but not MAM-17 treated mice exhibited enhanced hyperlocomotion after acute MK-801 administration, compared to saline treated mice. Male MAM-16, but not MAM-17, treated mice showed reduced pre-pulse inhibition of the acoustic startle reflex. Both male and female MAM-16 and MAM-17 treated mice exhibited smaller hippocampal (HPC) size and thinning of the prefrontal cortex (PFC), but only male MAM-16 treated mice showed decreased parvalbumin expression in HPC and PFC. Similarly, both male and female MAM-16 treated mice displayed impaired contextual fear memory and significantly reduced long-term potentiation (LTP) in the HPC CA1 synapses. However, male, but not female, MAM-16 treated mice exhibited deficits in the delayed alternation task and LTP in layer II PFC synapses. Proteomic analyses of PFC lysates further showed significant MAM- and sex-dependent differences in protein expression regulation. Our results demonstrate that while both male and female mice, prenatally exposed to MAM on GD16, display several core schizophrenia-like deficits and impairments in the hippocampus, only male MAM-treated mice have PFCdependent cognitive deficits.


Assuntos
Modelos Animais de Doenças , Hipocampo/fisiopatologia , Córtex Pré-Frontal/fisiopatologia , Esquizofrenia/fisiopatologia , Caracteres Sexuais , Animais , Percepção Auditiva/fisiologia , Medo/fisiologia , Feminino , Hipocampo/patologia , Potenciação de Longa Duração/fisiologia , Masculino , Memória/fisiologia , Acetato de Metilazoximetanol , Camundongos , Camundongos Endogâmicos C57BL , Córtex Pré-Frontal/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Inibição Pré-Pulso/fisiologia , Proteoma , Reflexo de Sobressalto/fisiologia , Esquizofrenia/patologia , Psicologia do Esquizofrênico
17.
Neural Regen Res ; 13(6): 1054-1060, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29926833

RESUMO

After spinal cord injury, the number of glial cells and motor neurons expressing bone morphogenetic protein 7 (BMP7) increases, indicating that upregulation of BMP7 can promote nerve repair. We, therefore, tested whether direct injection of BMP7 into acutely injured rat spinal cord can affect neurological recovery. Allen's impactor was used to create spinal cord injury at T10. The injury site was then injected with 50 ng BMP7 (BMP7 group) or physiological saline (control group) for 7 consecutive days. Electrophysiological examination showed that the amplitude of N1 in motor evoked potentials (MEP) decreased after spinal cord injury. At 8 weeks post-operation, the amplitude of N1 in the BMP7 group was remarkably higher than that at 1 week post-operation and was higher than that of the control group. Basso, Beattie, Bresnahan scale (BBB) scores, hematoxylin-eosin staining, and western blot assay showed that at 1, 2, 4 and 8 weeks post-operation, BBB scores were increased; Nissl body staining was stronger; the number of Nissl-stained bodies was increased; the number of vacuoles gradually decreased; the number of synapses was increased; and the expression of neuronal marker, neurofilament protein 200, was increased in the hind limbs of the BMP7 group compared with the control group. Western blot assay showed that the expression of GFAP protein in BMP7 group and control group did not change significantly and there was no significant difference between the BMP7 and control groups. These data confirmed that local injection of BMP7 can promote neuronal regeneration after spinal cord injury and promote recovery of motor function in rats.

18.
Brain Struct Funct ; 223(4): 1779-1795, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29214509

RESUMO

The gray short-tailed opossum (Monodelphis domestica) is a small marsupial gaining recognition as a laboratory animal in biomedical research. Despite numerous studies on opossum neuroanatomy, a consistent and comprehensive neuroanatomical reference for this species is still missing. Here we present the first three-dimensional, multimodal atlas of the Monodelphis opossum brain. It is based on four complementary imaging modalities: high resolution ex vivo magnetic resonance images, micro-computed tomography scans of the cranium, images of the face of the cutting block, and series of sections stained with the Nissl method and for myelinated fibers. Individual imaging modalities were reconstructed into a three-dimensional form and then registered to the MR image by means of affine and deformable registration routines. Based on a superimposition of the 3D images, 113 anatomical structures were demarcated and the volumes of individual regions were measured. The stereotaxic coordinate system was defined using a set of cranial landmarks: interaural line, bregma, and lambda, which allows for easy expression of any location within the brain with respect to the skull. The atlas is released under the Creative Commons license and available through various digital atlasing web services.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Monodelphis/anatomia & histologia , Fatores Etários , Animais , Crioultramicrotomia , Neuroanatomia , Valores de Referência , Técnicas Estereotáxicas
19.
J Neurosci Methods ; 286: 102-113, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28577985

RESUMO

BACKGROUND: The brain of the common marmoset (Callithrix jacchus) is becoming a popular non-human primate model in neuroscience research. Because its brain fiber connectivity is still poorly understood, it is necessary to collect and present connection and trajectory data using tracers to establish a marmoset brain connectivity database. NEW METHOD: To visualize projections and trajectories of axons, brain section images were reconstructed in 3D by registering them to the corresponding block-face brain images taken during brain sectioning. During preprocessing, autofluorescence of the tissue was reduced by applying independent component analysis to a set of fluorescent images taken using different filters. RESULTS: The method was applied to a marmoset dataset after a tracer had been injected into an auditory belt area to fluorescently label axonal projections. Cortical and subcortical connections were clearly reconstructed in 3D. The registration error was estimated to be smaller than 200 µm. Evaluation tests on ICA-based autofluorescence reduction showed a significant improvement in signal and background separation. COMPARISON WITH EXISTING METHODS: Regarding the 3D reconstruction error, the present study shows an accuracy comparable to previous studies using MRI and block-face images. Compared to serial section two-photon tomography, an advantage of the proposed method is that it can be combined with standard histological techniques. The images of differently processed brain sections can be integrated into the original ex vivo brain shape. CONCLUSIONS: The proposed method allows creating 3D axonal projection maps overlaid with brain area annotations based on the histological staining results of the same animal.


Assuntos
Mapeamento Encefálico , Encéfalo/citologia , Encéfalo/diagnóstico por imagem , Callithrix/anatomia & histologia , Imageamento Tridimensional , Vias Neurais/diagnóstico por imagem , Animais , Imageamento por Ressonância Magnética
20.
J Chem Neuroanat ; 77: 110-120, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27344962

RESUMO

The periaqueductal gray (PAG) is a mesencephalic brain structure involved in the expression of numerous behaviours such as maternal, sexual and emotional. Histological approaches showed the PAG is composed by subdivisions with specific cell organisation, neurochemical composition and connections with the rest of the brain. The comparison of studies performed in rodents and cats as the most often examined species, suggests that PAG organisation differs between mammals. However, we should also consider the plurality of the methods used in these studies that makes difficult the comparison of the PAG organisation between species. Therefore, to study the PAG in all mammals including human, the most relevant in vivo imaging method seems to be the magnetic resonance imaging (MRI). The purpose of this review was to summarize the knowledge of the anatomical organisation of the PAG in mammals and highlights the benefits of MRI methods to extend this knowledge. Results obtained by MRI so far support the conclusions of ex vivo studies, especially to describe the subdivisions and the connections of the PAG. In these latter, diffusion-weighted MRI and functional connectivity seem the most appropriate methods. In conclusion firstly, the MRI seems to be the best judicious method to compare species and improve the comprehension of the role of the PAG. Secondly, MRI is an in vivo method aimed to manage repeated measures in the same cohort of subjects allowing to study the impact of aging and the development on the anatomical organisation of the PAG.


Assuntos
Imageamento por Ressonância Magnética/métodos , Mamíferos/anatomia & histologia , Substância Cinzenta Periaquedutal/anatomia & histologia , Animais , Química Encefálica , Humanos , Substância Cinzenta Periaquedutal/citologia , Substância Cinzenta Periaquedutal/metabolismo
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